环县典型草原放牧家畜践踏的模拟研究
|
摘要
践踏是放牧家畜对草地的三大影响因素之一，也是导致草原全面退化的最主要的原因。为了深入探索草地退化机理和草地恢复机制，研究家畜对草地的践踏作用是非常必要的，但是由于技术和方法的限制，相关的研究报道较少，极大地削弱了我们对草地农业生态系统的主体—草畜界面生态动力机制的整体认识。基于上述原因，在我国干旱半干旱的黄土高原典型草原区——兰州大学环县草畜生产系统野外实验点，通过滩羊夏季轮牧试验践踏强度的跟群观测、践踏同质性试验、模拟降水与试验践踏的双因子试验进行了为期2年的野外试验系列研究。首先建立了践踏强度指标和严格的践踏试验方法，然后围绕践踏强度这一主线重点揭示土(土壤理化性质，土壤侵蚀)—草(地下生物量)—畜(践踏)在不同降水条件下的互作机制，对家畜践踏这一不受关注的“小”问题，应用数学生态学的原理和方法开展综合性、系统性的研究，探讨家畜践踏对草地的作用。主要结果如下：
1、提出践踏强度是在特定的放牧方式(自由放牧或轮牧)下，单一种或组合种畜群单位时间内(通常指一个放牧季内)对单位草地面积所施加的践踏重力或践踏面积，它应有三种表示方法：重力表示法、面积表示法、频率表示法。首次提出了践踏单位和践踏当量概念，以明确践踏强度的计算标准和折算标准，有助于使当前不统一的践踏强度表示方法规范化。
2、通过在环县典型草原不同放牧强度下轮牧试验的跟群观测，获得了家畜践踏强度依放牧强度的幂函数式增大的定量结论，揭示了放牧强度与践踏强度的关系，该定量结论为调控践踏提供了实践途径，为制定科学的放牧制度提供了又一新的理论与实践的基础。
3、研制了模拟践踏器，通过对试验践踏样区与传统的滩羊夏季轮牧样区的土壤和植被的6项指标的对比研究表明，模拟践踏与放牧滩羊的践踏具有同质性，为本研究提供了将践踏与采食和排泄的影响区分开来的试验手段，使能对践踏进行精确的研究。
4、根系是植物体受放牧家畜采食影响较小，而受放牧活动机械干扰(践踏)较大的部位，但践踏对草地地下生物量影响的专项研究较少。对以0-10cm地下生物量为目标函数，以践踏强度、牧草生长期降水量为决策变量的践踏、降水耦合模型，以地下生物量最大化为准则，进行解析和寻优分析，确定出环县典型草原适宜的草地放牧强度是3.84-5.09羊单位／hm~2。
5、对模拟降水与试验践踏的双因子野外控制试验的48个试验处理组合的5项土壤化学指标进行分析，结果表明在践踏强度梯度上碱解氮(mg／kg)和全磷(％)差异显著；在模拟降水量梯度上，碱解氮(mg／kg)、全磷(％)、速效磷(mg／kg)和有机质(％)差异显著，表明土壤化学性状对模拟降水更为敏感。践踏强度与模拟降水量交互效应对碱解氮(mg／kg)、全磷(％)、有机质(％)影响显著，说明践踏和模拟降水均是引起土壤化学性质变化的驱动力因素。
6、通过模拟降水与试验践踏的野外控制试验，对不同试验组合样区表土(0-15cm)质地的机械组成，利用分形模型计算了土壤粒径分形维数，计算结果表明：分维数值均表现为重度践踏区＜中度践踏区＜轻度践踏区＜对照区，说明分维数指标对践踏强度呈一定的负相关，即践踏强度越大土壤的分维数值越小。但分形维数递减幅度与模拟降水处理水平相关，在模拟降水处理水平依次为干旱、自然降水、平水、丰水时，粒径分形维数递减幅度依次为4.33％、2.61％、1.34％和1.23％。降水与践踏的匹配关系，对形成确定的分形维数具有决定性作用，其回归模型是：F=2.427+2.0982×10~(-4)W-1.3333x10~(-4)T。土壤侵蚀过程在土壤颗粒分形维数上亦可表现为分形维数降低，因此，在此种意义上来说，土壤分维数的测算对土壤侵蚀程度的评估具有一定的指示意义，对进一步研究放牧草地土壤侵蚀机理可能具有推动作用。
7、降水和践踏通过各种不同强度的侵蚀外营力组合方式，改变土壤可蚀性。以牧草生长期单位面积累计践踏量和模拟降水量为自变量的土壤可蚀性K值的ANN(Artificial Neural Networks)关系模型具有较好的拟合结果和预测能力，说明直接从输入到草地生态系统的外侵蚀营力着手，跨越系统内土壤可蚀性变化的内在的复杂的隐含过程，建立的输出端—土壤可蚀性K值与土壤侵蚀外营力的ANN(Artificial Neural Networks)关系模型是准确确定土壤可蚀性K值的一次全新的成功尝试。
8、模拟降水和试验践踏通过各种不同的组合方式改变土壤抗蚀力，从而起到对草地土壤侵蚀的增减作用。在牧草生长期，中、高强度践踏对土壤的扰动，加剧了干旱状况下土壤风蚀的风险，降水具有双向调节作用，即在践踏强度升高时具有降低土壤侵蚀的作用，而在践踏强度降低时又具有升高土壤侵蚀的作用，但显然模拟降水对土壤侵蚀的限制作用小于践踏对侵蚀的增加作用。构建的以试验期土壤侵蚀模数为因变量，以践踏、模拟降水累计量为自变量的机理模型，可为黄土高原放牧地土壤侵蚀产沙量提供计算方法。据此，以土壤侵蚀最小化为目标，对于不同的牧草生育期降水量，解析得到的最适放牧强度显然是对正确确定载畜量的一次新的尝试。
9、在可持续发展前提下，仅仅根据草畜的供求关系管理放牧系统远远不够，科学管理放牧系统还需要兼顾“地下生物量”和“土壤侵蚀”状况，为此提出：适宜的放牧率=min(理论载畜量，以地下生物量最大化为准则确定的适宜放牧率，以土壤侵蚀最小化为目标确定的最适放牧率)。由此得出环县典型草原在牧草生长期降水量为224.9mm时，最适宜的践踏强度为：39次羊践踏／m~2·期，对应的放牧强度为：3.8羊单位／hm~2。
An animal exerts three main influences on pasture - it treads, removes leaves (defoliates), and excretes upon it. Continued overgrazing and erosion cause range degradation by excessive animal trampling. Published studies that have examined the effects of grazing often do not distinguish between effects arising from these separate activities. Little is known about the result of trampling-induced feedback among the soil environment, grass and their interdependency. In addition, more information is needed on the effects of animal trampling on the managed grazing ecosystems. In typical steppe of loess plateau regions, where the management objective is maintaining grassland ecosystem structure and function, the impacts of grazing trampling can be a serious problem. This was one of the reasons for conducting this study on trampling effects. The object of the study was to evaluate separately the effect of trampling in typical steppe of Huanxian County in eastern Gansu Province, China. A series of field experiments were conducted there, which lasted for two years. They were involved of trampling intensity observation of tailing up Tan-sheep rotational grazing trail in summer season, trampling homogeneity trial, double factors trail between simulated precipitation and experimental trampling. Firstly, the index of trampling intensity and the strict trial method of experimental trampling were set up. Techniques of Mathematical Ecology were used to describe the variation among the response variables for the use levels (trampling intensity and simulated precipitation). This paper quantifies the impact of controlled experimental trampling on belowground plant biomass, soil physical and chemical properties and soil erosion under different precipitation conditions with tramping intensity as its core. The results were as follows.
1. The trampling intensity (TI) proposed in the paper is defined under free or rotational grazing, trampling area or trampling pressure of grazing single or multiple livestock per hectare during a unit time. It has three expressive methods: trampling pressure method, trampling area method, trampling frequency method. The trampling unit and Trampling Equivalent Unit (TEU) were put forward for the first time in order to define the calculating standard and converting standard of TI.
2. By tailing up and observing the flocks on typical steppe of Huanxian County in Eastern Gansu, China, a relation equation by regression analysis showed that livestock trampling intensity is increased by the power function of grazing intensity. This fully demonstrated that adjusting and controlling the trampling effects of grazing livestock is an important indication of grazing management. The trampling effects of grazing livestock played a key role in preventing the degeneration and maintaining the wholesomeness of the grassland.
3. Manufacture of trampler was imitated for mechanic characteristics of Tan-sheep trampling. By a simulation homogeneity experiment, we compared experimental trampling and traditional Tan-sheep rotational grazing in summer season. Statistical analyses (t test) indicated that there were no significant differences between modelling Tan-sheep trampling and traditional rotational grazing in the height of leaf layer, species number of plant, the water content of top layer (0-15cm), the soil porosity, bulk density and soil compaction. There is homogeneity between experimental trampling and traditional grazing in the effect of grassland trampled. This lay the foundation for future research in animal trampling effects for more effectively.
4. Early research on grassland root systems focused on qualitative descriptions of root system structure. But the response effects of roots for different trampling intensity are not well-understood. Taking trampling intensity and rainfall as independent variables, the coupling model of underground plant biomass of 0-10cm layer was scanned optimization with underground plant biomass maximum as a target. The most suitable grazing intensity for the typical steppe of Huanxian County was decided to be 3.84-5.09 sheep unit/hm~2 which is converted by the relation equation between trampling intensity and grazing intensity. The models offered a new pattern and quantitative tool for the grazing system management.
5. There are 48 experimental treatment combinations on five soil chemical indicators in field controlling experiment of two factors: experimental trampling and simulated precipitation. The analysis results by multivariate and multiple analyses of variance indicate that there is significant difference between hydro N (mg/kg) and total P (%) in trampling intensity gradient. However, there are significant differences among hydro N (mg/kg), total P (%), available P (mg/kg) and the content of soil organic matter (%) in simulated precipitation gradient. This shows that soil chemical properties are more sensitive to simulated precipitation. The effects of interaction between experimental trampling and simulated precipitation have significant influences on hydro N (mg/kg), total P (%) and organic content. Trampling and simulated precipitation factors play a role in facilitating ecosystem state change in the typical steppe of Huanxian County in Eastern Gansu, China.
6. We analyzed the soil mechanical composition (0-15cm) of different trial sample plots in field controlling experiment of two factors: experimental trampling and simulated precipitation. Fractal dimension can be calculated by using fractal model. The result shows that fractal dimension characterized by heavy trampling plot 7. The sensitivity of soil erosion to trampling-caused was changed with various different combinations of experimental trampling and simulated precipitation. Compared with traditional regression model, the artificial neural network model by Error Back Propagation (BP) can complete the news treatment of the whole network by means of a mutual function between the neural units, and has a lot of merits of self-learning, self-adjusting and fault tolerance such like. Therefore it is feasible that the soil erodibility factor K value is calculated by the neural network. Soil erodibility is complicated, which is affected by many factors such as trampling and precipitation. The artificial neural network model skipped the mechanism of soil erodibility, conducted research on soil erodibility by both trampling and rainfall factors. Obviously, this was an innovative attempt to precisely evaluate soil erodibility for understanding soil erosion regularity.
8. Trampling directly facilitates erosion by hoof. Trampling of the soil is the most important factor contributing to erosion. Study results indicated that in grass growth period, moderate and heavy trampling aggravated soil erosion risk under arid circumstances. Precipitation has the effects of two-side regulating soil erosion. With increasing trampling intensities, precipitation can lower soil erosion modulus, but soil erosion modulus will increase with decreasing trampling intensities. However, the restriction effects of simulated precipitation on soil erosion were less than the trampling effects on soil erosion. The mechanism model, which took soil erosion modulus as dependent variable and takes experimental trampling and simulated precipitation as independent variable, was validated by experimental data. This can provide a new method for the evaluation of soil erosion in arid and semi-arid grassland regions. With soil erosion minimum as a target, the most suitable grazing intensity can be obtained by analyzing precipitation amount in different forage growth period. Obviously, this is an innovative attempt for ascertaining grazing capacity rationally.
9. The ecological restoration of degraded grassland ecosystems has become the key task for the future sustainable development. So an integrated method for calculating a rational stocking density should be adopted. It gives attention to two things: underground plant biomass and soil erosion, besides the balance between forage yield and livestock utilization. The most suitable grazing intensity calculated by the integrated method can be denoted as minimum ("determine livestock carrying capacity according to grass", the suitable grazing intensity with underground plant biomass maximum as a target, the suitable grazing intensity with soil erosion minimum as a target). As a result, the most suitable trampling intensity for the typical steppe grassland of Huanxian County is decided to be 39 UST /hm~2, in which the precipitation amount in forage growth period is 224.9mm, and the corresponding most suitable grazing intensity converting by the relation equation between trampling intensity and grazing intensity is 3.8 sheep unit/hm~2.
1、提出践踏强度是在特定的放牧方式(自由放牧或轮牧)下，单一种或组合种畜群单位时间内(通常指一个放牧季内)对单位草地面积所施加的践踏重力或践踏面积，它应有三种表示方法：重力表示法、面积表示法、频率表示法。首次提出了践踏单位和践踏当量概念，以明确践踏强度的计算标准和折算标准，有助于使当前不统一的践踏强度表示方法规范化。
2、通过在环县典型草原不同放牧强度下轮牧试验的跟群观测，获得了家畜践踏强度依放牧强度的幂函数式增大的定量结论，揭示了放牧强度与践踏强度的关系，该定量结论为调控践踏提供了实践途径，为制定科学的放牧制度提供了又一新的理论与实践的基础。
3、研制了模拟践踏器，通过对试验践踏样区与传统的滩羊夏季轮牧样区的土壤和植被的6项指标的对比研究表明，模拟践踏与放牧滩羊的践踏具有同质性，为本研究提供了将践踏与采食和排泄的影响区分开来的试验手段，使能对践踏进行精确的研究。
4、根系是植物体受放牧家畜采食影响较小，而受放牧活动机械干扰(践踏)较大的部位，但践踏对草地地下生物量影响的专项研究较少。对以0-10cm地下生物量为目标函数，以践踏强度、牧草生长期降水量为决策变量的践踏、降水耦合模型，以地下生物量最大化为准则，进行解析和寻优分析，确定出环县典型草原适宜的草地放牧强度是3.84-5.09羊单位／hm~2。
5、对模拟降水与试验践踏的双因子野外控制试验的48个试验处理组合的5项土壤化学指标进行分析，结果表明在践踏强度梯度上碱解氮(mg／kg)和全磷(％)差异显著；在模拟降水量梯度上，碱解氮(mg／kg)、全磷(％)、速效磷(mg／kg)和有机质(％)差异显著，表明土壤化学性状对模拟降水更为敏感。践踏强度与模拟降水量交互效应对碱解氮(mg／kg)、全磷(％)、有机质(％)影响显著，说明践踏和模拟降水均是引起土壤化学性质变化的驱动力因素。
6、通过模拟降水与试验践踏的野外控制试验，对不同试验组合样区表土(0-15cm)质地的机械组成，利用分形模型计算了土壤粒径分形维数，计算结果表明：分维数值均表现为重度践踏区＜中度践踏区＜轻度践踏区＜对照区，说明分维数指标对践踏强度呈一定的负相关，即践踏强度越大土壤的分维数值越小。但分形维数递减幅度与模拟降水处理水平相关，在模拟降水处理水平依次为干旱、自然降水、平水、丰水时，粒径分形维数递减幅度依次为4.33％、2.61％、1.34％和1.23％。降水与践踏的匹配关系，对形成确定的分形维数具有决定性作用，其回归模型是：F=2.427+2.0982×10~(-4)W-1.3333x10~(-4)T。土壤侵蚀过程在土壤颗粒分形维数上亦可表现为分形维数降低，因此，在此种意义上来说，土壤分维数的测算对土壤侵蚀程度的评估具有一定的指示意义，对进一步研究放牧草地土壤侵蚀机理可能具有推动作用。
7、降水和践踏通过各种不同强度的侵蚀外营力组合方式，改变土壤可蚀性。以牧草生长期单位面积累计践踏量和模拟降水量为自变量的土壤可蚀性K值的ANN(Artificial Neural Networks)关系模型具有较好的拟合结果和预测能力，说明直接从输入到草地生态系统的外侵蚀营力着手，跨越系统内土壤可蚀性变化的内在的复杂的隐含过程，建立的输出端—土壤可蚀性K值与土壤侵蚀外营力的ANN(Artificial Neural Networks)关系模型是准确确定土壤可蚀性K值的一次全新的成功尝试。
8、模拟降水和试验践踏通过各种不同的组合方式改变土壤抗蚀力，从而起到对草地土壤侵蚀的增减作用。在牧草生长期，中、高强度践踏对土壤的扰动，加剧了干旱状况下土壤风蚀的风险，降水具有双向调节作用，即在践踏强度升高时具有降低土壤侵蚀的作用，而在践踏强度降低时又具有升高土壤侵蚀的作用，但显然模拟降水对土壤侵蚀的限制作用小于践踏对侵蚀的增加作用。构建的以试验期土壤侵蚀模数为因变量，以践踏、模拟降水累计量为自变量的机理模型，可为黄土高原放牧地土壤侵蚀产沙量提供计算方法。据此，以土壤侵蚀最小化为目标，对于不同的牧草生育期降水量，解析得到的最适放牧强度显然是对正确确定载畜量的一次新的尝试。
9、在可持续发展前提下，仅仅根据草畜的供求关系管理放牧系统远远不够，科学管理放牧系统还需要兼顾“地下生物量”和“土壤侵蚀”状况，为此提出：适宜的放牧率=min(理论载畜量，以地下生物量最大化为准则确定的适宜放牧率，以土壤侵蚀最小化为目标确定的最适放牧率)。由此得出环县典型草原在牧草生长期降水量为224.9mm时，最适宜的践踏强度为：39次羊践踏／m~2·期，对应的放牧强度为：3.8羊单位／hm~2。
An animal exerts three main influences on pasture - it treads, removes leaves (defoliates), and excretes upon it. Continued overgrazing and erosion cause range degradation by excessive animal trampling. Published studies that have examined the effects of grazing often do not distinguish between effects arising from these separate activities. Little is known about the result of trampling-induced feedback among the soil environment, grass and their interdependency. In addition, more information is needed on the effects of animal trampling on the managed grazing ecosystems. In typical steppe of loess plateau regions, where the management objective is maintaining grassland ecosystem structure and function, the impacts of grazing trampling can be a serious problem. This was one of the reasons for conducting this study on trampling effects. The object of the study was to evaluate separately the effect of trampling in typical steppe of Huanxian County in eastern Gansu Province, China. A series of field experiments were conducted there, which lasted for two years. They were involved of trampling intensity observation of tailing up Tan-sheep rotational grazing trail in summer season, trampling homogeneity trial, double factors trail between simulated precipitation and experimental trampling. Firstly, the index of trampling intensity and the strict trial method of experimental trampling were set up. Techniques of Mathematical Ecology were used to describe the variation among the response variables for the use levels (trampling intensity and simulated precipitation). This paper quantifies the impact of controlled experimental trampling on belowground plant biomass, soil physical and chemical properties and soil erosion under different precipitation conditions with tramping intensity as its core. The results were as follows.
1. The trampling intensity (TI) proposed in the paper is defined under free or rotational grazing, trampling area or trampling pressure of grazing single or multiple livestock per hectare during a unit time. It has three expressive methods: trampling pressure method, trampling area method, trampling frequency method. The trampling unit and Trampling Equivalent Unit (TEU) were put forward for the first time in order to define the calculating standard and converting standard of TI.
2. By tailing up and observing the flocks on typical steppe of Huanxian County in Eastern Gansu, China, a relation equation by regression analysis showed that livestock trampling intensity is increased by the power function of grazing intensity. This fully demonstrated that adjusting and controlling the trampling effects of grazing livestock is an important indication of grazing management. The trampling effects of grazing livestock played a key role in preventing the degeneration and maintaining the wholesomeness of the grassland.
3. Manufacture of trampler was imitated for mechanic characteristics of Tan-sheep trampling. By a simulation homogeneity experiment, we compared experimental trampling and traditional Tan-sheep rotational grazing in summer season. Statistical analyses (t test) indicated that there were no significant differences between modelling Tan-sheep trampling and traditional rotational grazing in the height of leaf layer, species number of plant, the water content of top layer (0-15cm), the soil porosity, bulk density and soil compaction. There is homogeneity between experimental trampling and traditional grazing in the effect of grassland trampled. This lay the foundation for future research in animal trampling effects for more effectively.
4. Early research on grassland root systems focused on qualitative descriptions of root system structure. But the response effects of roots for different trampling intensity are not well-understood. Taking trampling intensity and rainfall as independent variables, the coupling model of underground plant biomass of 0-10cm layer was scanned optimization with underground plant biomass maximum as a target. The most suitable grazing intensity for the typical steppe of Huanxian County was decided to be 3.84-5.09 sheep unit/hm~2 which is converted by the relation equation between trampling intensity and grazing intensity. The models offered a new pattern and quantitative tool for the grazing system management.
5. There are 48 experimental treatment combinations on five soil chemical indicators in field controlling experiment of two factors: experimental trampling and simulated precipitation. The analysis results by multivariate and multiple analyses of variance indicate that there is significant difference between hydro N (mg/kg) and total P (%) in trampling intensity gradient. However, there are significant differences among hydro N (mg/kg), total P (%), available P (mg/kg) and the content of soil organic matter (%) in simulated precipitation gradient. This shows that soil chemical properties are more sensitive to simulated precipitation. The effects of interaction between experimental trampling and simulated precipitation have significant influences on hydro N (mg/kg), total P (%) and organic content. Trampling and simulated precipitation factors play a role in facilitating ecosystem state change in the typical steppe of Huanxian County in Eastern Gansu, China.
6. We analyzed the soil mechanical composition (0-15cm) of different trial sample plots in field controlling experiment of two factors: experimental trampling and simulated precipitation. Fractal dimension can be calculated by using fractal model. The result shows that fractal dimension characterized by heavy trampling plot
8. Trampling directly facilitates erosion by hoof. Trampling of the soil is the most important factor contributing to erosion. Study results indicated that in grass growth period, moderate and heavy trampling aggravated soil erosion risk under arid circumstances. Precipitation has the effects of two-side regulating soil erosion. With increasing trampling intensities, precipitation can lower soil erosion modulus, but soil erosion modulus will increase with decreasing trampling intensities. However, the restriction effects of simulated precipitation on soil erosion were less than the trampling effects on soil erosion. The mechanism model, which took soil erosion modulus as dependent variable and takes experimental trampling and simulated precipitation as independent variable, was validated by experimental data. This can provide a new method for the evaluation of soil erosion in arid and semi-arid grassland regions. With soil erosion minimum as a target, the most suitable grazing intensity can be obtained by analyzing precipitation amount in different forage growth period. Obviously, this is an innovative attempt for ascertaining grazing capacity rationally.
9. The ecological restoration of degraded grassland ecosystems has become the key task for the future sustainable development. So an integrated method for calculating a rational stocking density should be adopted. It gives attention to two things: underground plant biomass and soil erosion, besides the balance between forage yield and livestock utilization. The most suitable grazing intensity calculated by the integrated method can be denoted as minimum ("determine livestock carrying capacity according to grass", the suitable grazing intensity with underground plant biomass maximum as a target, the suitable grazing intensity with soil erosion minimum as a target). As a result, the most suitable trampling intensity for the typical steppe grassland of Huanxian County is decided to be 39 UST /hm~2, in which the precipitation amount in forage growth period is 224.9mm, and the corresponding most suitable grazing intensity converting by the relation equation between trampling intensity and grazing intensity is 3.8 sheep unit/hm~2.
引文
[1]Accocks, J.P.H. Veld types of South Africa (3rd ed). Pretoria: Botanical Research Institute, Department of Agriculture and Water Supply, South Africa. 1988, 1-5.
[2]Adams J. M., Faure H., Faure-Denard L., McGlade J. M., Woodward F. I. Increases in terrestrial carbon storage from the Last Glacial Maximum to the present. Nature.1990, 348:711-714.
[3]Amy Zacheis; Roger W.; Ruess ,Jerry ;W. Hupp. Nitrogen dynamics in an Alaskan salt marsh following spring use by geese. Oecologia.2002, 130:600-608.
[4]Andersen, U. V. Resistance of Danish coastal vegetation types to human trampling. Biological Conservation.1995, 71:223-230.
[5]Anderson, D. C, Harper, K. T. & Rushforth, S. R. Recovery of cryptogamic crusts from grazing on Utah winter ranges. J. Range Manag.1982,35:355-359.
[6]Andr's-abell'n, M; Francisco,R. and Antonio,D. Asseeement of trampling simulation impacts on native vegetation in Mediterranean sclerophyllous forest. Environmental Monitoring and Assessment.2006, 120:93-107.
[7]Augustine, D.J., Frank, D.A. Effects of migratory grazers on spatial heterogeneity of soil nitrogen properties in a grassland ecosystem. Ecology. 2001, 82:3149-3162.
[8]Azenegashe, O. A.; Allen, V. and Fontenot, J. Grazing sheep and cattle together or separately: effect on soil and plants. Agron. J. 1997, 89:380-386.
[9]Bakken,L.R.; Borresen,T.; Njos,A. Effect of soil compaction by tractor traffic on soil structure, denitrification, and yield of wheat. Journal of Soil Science. 1987, 38(3):541-552.
[10]Bardgett, R. D.; Leemans, D. K. The short-term effects of cessation of fertilizer applications, limiting and grazing on microbial biomass and activity in a reseeded upland grassland soil. Biology and Fertility of Soils.1995, 19:148-154.
[11]Barrie Low A, Rebelo AG Vegetation of South Africa, Lesotho and Swaziland. Pretoria: Department of Environmental Affairs & Torism.1998.
[12]Bates, A. J.; Sadler, J.P.; Fowles, A. P. Livestock trampling reduces the conservation value of beetle communities on high quality exposed riverine sediments. Biodivers Conserv.2006,DOI 10.1007/s10531-006-9028-7.
[13]Bates, G. H. The vegetation of footpaths, sidewalks, cart-tracks and gateways. Journal of Ecology. 1935. 23:470-487.
[14]Bates, G.H. A device for the observation of root growth in the soil. Nature.1937, 139:966-967.
[15]Batjes, N. H. The total C and N in soils of the world. European J Soil Society.1996,47:51-63.
[16]Bauer,A.; Cole, C. V; Black, A. L.Soil Property comparisons in virgin grasslands between grazed and non-grazed management systems. Soil Science Society of America Journalist. 1987,51:176-182.
[17]Bayfield, N. Recovery of four montane heath communities on Cairngorm, Scotland from disturbance by trampling. Biological Conservation.1979, 15:165-181.
[18]Bell,K.L. and Bliss,L.C.Alpine disturbance studies:Olympic National Park,USA. Biological Conservation. 1973, 5:25-32.
[19]Belovsky, G F. Optimal foraging and community structure implications for a guild of generalist grassland herbivore. Oecologia. 1981,70:35-52.
[20]Betteridge, K.; Mackay, A. D.; Stepberd, T. G. et al. Effect of cattle and sheep treading on surface configuration of a sedimentary hill soil. Anstralian Journal of Soil Research.1999, 37(4):743-760.
[21]Birch, C.P.D.; Vuichard, N. and Werkman, B.R. Modelling the effects of patch size on vegetation dynamics: bracken (Pteridium aquilinum (L.) Kuhn) under grazing. Annals of Botany.2000, 85 (Supplement B): 63-76.
[22]Blumenthal, M.J.; Ison, T.L. Plant population dynamics in subterranean clover and murex medic swards, 3. effects of pod burial, summer grazing and autumn cultivation on emergence. Australian Journal of Experimental Agriculture.1996, 36(5):533-538.
[23]Boelhouwers, J.; Scheepers, T. The role of antelope trampling on scarp erosion in a hyper-arid environment, Skeleton Coast, Namibia. Journal of Arid Environments.2004, 58:545-557.
[24]Bohn C.C. and Buckhouse J.C. Some responses of riparian soils to grazing anagement in northeastern Oregon. Journal of Range Management. 1985, 38:378-381.
[25]Breland, T. A.; Hansen, S. Nitrogen mineralization and microbial biomass as affected by soil compaction. Soil Biol.Biochem. 1996,28:655-663.
[26]Brown, R. W. The water relations of range plants: Adaptations to water deficits. Pages 291-413 in D.J. Bedunah and R. Sosebee (eds.), Wildland plants: hysiological ecology and developmental morphology. Society for Range Management, Denver, Colorado. 1995.
[27]Bullock, J.M.; Hilt, B.C.; Dale M.P. and Silvertown, J. An experimental study of the effects of sheep grazing on vegetation change in species-poor grassland and the role of seedling recruitment into gaps. J. Appl. Ecol. 1994, 31:493-507.
[28]Burgess, C.P.; Chapman, R.; Singleton, P.L.; Thorn, E.R. Shallow mechanical loosening of a soil under dairy cattle grazing: effects on soil and pasture. New Zealand Journal of Agricultural Research. 2000, 43(2):278-290.
[29]Burke, I. C.; Laurenroth, W. K.; Milchunas, D. G. Biogeochemistry of managed grasslands in central North America. In: Pau, I. E .A. eds. Soil Organic Matter in Temperate Ag roecosystems: Long-term Experiments in North America. Boca Raton: CRC Press. 1997. p85-102.
[30]Butler, D.R. Zoogemorphology. Cambridge University Press, Cambridge. 1995. p231.
[31]Byington, E.K. Grazing land management and water quality. Harpers Ferry (WV): American Society of Agronomy and Crop Science Society of America. 1986.
[32]Cao, G.M.; Tang, Y.H.; Mo, W.H. Grazing intensity alters soil respiration in an alpine meadow on the Tibetan plateau. Soil Biology and Biochemistry.2004, 36:237-243.
[33]Chanasky, D. S. Grazing impacts on bulk density and soil strength in the foothills fescue grasslands of Alberta Canada. Canadian J. of soil science.1995, 75(4):551-557.
[34]Chepil, W. S. Properties of soil which influence wind erosion: 1. The governing principle of surface roughness. Soil Sci. 1950,69:149-162.
[35]Cingolani, A. M.; Cabido, M. R.; Renison, D.; Solis, V. N.Combined effects of environment and grazing on vegetation structure in Argentine granite grasslands. J. Veg. Sci.2003, 14:223-232.
[36]Coffin, D. P.; Laycock, W. A.; Lauenroth, W. K. Disturbance intensity and above- and below-ground herbivory effects on long-tern (1 4 years) recovery of a semiarid grassland. Plant Ecol. 1998, 139:221 -233.
[37]Cole, D. N. and Trull, S. J. Quantifying vegetation response to recreational disturbance in the North Cascades, Washington. Northwest Science.1992,66:229-236.
[38]Cole, D. N. Effects of three seasons of experimental trampling on five montane forest communities and a grassland in Western Montana, USA, Biol. Conserv.1987,40:219-244.
[39]Cole, D. N., and N. Bayfield. Recreational trampling of vegetation: Standard experimental procedures. Biological Conservation. 1993,63:209-215.
[40]Cole, D.N. and Landres, P.B. In Knight, R.L., Gutzwiller, K.J. (eds.) Wildlife and Recreationists - Coexistence through Management and Research, pp.183-202. DC: Island Press. Washington, USA, 1995.
[41]Cole, D.N. and Monz,C.A. Impacts of camping on vegetation: response and recovery following acute and chronic disturbance. Environmental Management. 2003,32(6):693-705.
[42]Cole, D.N. and Spildie, D. R. Hiker, horse and llama trampling effects on native vegetation in Montana, USA. Journal of Environmental Management. 1998, 53:61-71.
[43]Cole, D.N. Disturbance of natural vegetation by camping: experimental applications of low-level stress. Environmental Management. 1995d, 19:405-416.
[44]Cole, D.N. Experimental trampling of vegetation, I. relationship between trampling intensity and vegetation response. Journal of Applied Ecology. 1995a, 32:203-214.
[45]Cole, D.N. Experimental trampling of vegetation, II. Predictors of resistance and resilience. Journal of Apply Ecology.1995b, 32:215-224.
[46]Cole,D.N. Recreational Trampling Experiments: Effects of Trampler Weight and Shoe Type. USDA Forest Service, Research Note INT-RN-425. 1995c.
[47]Colin, P.D. B. The influence of position on genet growth: a simulation of a population of bracken (Pteridium aquilinum (L.) Kuhn) genets under grazing. Evolutionary Ecology. 2002, 15: 463-483.
[48]Conner, J. H. Diversity in tropical rain forests and coral reefs. Science. 1978,199:1302-1310.
[49]Conner, J. H. Social and economic influences on grazing management. In: Heitschmidt, R. K.; Stuth, J. W. (eds). Grazing management: An ecological perspective. Portland, Timber Press, 1991,p191-199.
[50]Coppolillo, P.B. Central-place analysis and modeling of landscape-scale resource use in an East African agropastoral system. Landscape Ecology .2001,16:205-219.
[51]Costanza R, Ralph d'Arge, Rudolf de Groot, et al. The value of the word's ecosystem services and natural capital. Nature.1997, 387:253-260.
[52]Craine, J.M.; D.A. Wedin; F.S. Chapin and P.B. Reich. Relationship between the structure of root systems and resource use for 11 North American grassland plants. Plant Ecology.2002, 165:85-100.
[53]Crawford, A. K. and Liddle, M. J. The effects of trampling on neutral grassland. Biological Conservation. 1977, 12:35-42.
[54] Cumming, H. M.; Cumming, G. S. Ungulate community structure and ecological processes: body size, hoof area and trampling in African savannas. Oecologia.2003, 134:560-568
[55] Dahlman, R. D, Kucera, C. L. Root productivity and turnover in nature prairie. Ecology. 1965, 46:104-116.
[56] Dakhah, M.; Gifford, G. F. Influence of vegetation, rock cover and trampling on infiltration rates and sediment production. Water Resource Bull.1980, 16:979-986.
[57] Dasmarnn, W. A method for estimating carrying capacity of rangelandss. Journal of Forestry.1945, (43):400-402.
[58] Dawson, L. A.; S. J. Graystonl; P. J. Murray; R. Cook; A. C. Gange; J. M. Rossl; S. M. Prattl; E. I. Duff and A. Treonis. Influence of pasture management (nitrogen and lime addition and insecticide treatment) on soil organisms and pasture root system dynamics in the field. Plant and Soil.2003,255: 121-130.
[59] Decaens, T. Degradation dynamics of surface earthworm casts in grassland of the eastern plains of Colombia. Biology and Fertility of Soil. 2000,32(2): 149-156.
[60] DeLuca, T. H.; Patterson, W. A. ; Freimund, Ⅳ, W. A.and Cole, D. N. Influence of llamas, horses and hikers on soil erosion from established recreation trails in Western Montana. Environmental Management. 1998, 22:255-262.
[61] Desjardins, T.; Andreux, F.; Volkoff, B. Organic carbon and ~(13)C contents in soils and soil size-fractions, and their changes due to deforestation and pasture installation in eastern Amazonia. Geoderma.1994, 61:103-118.
[62] Dianfa, Z.; Nianfeng, L.; Jie , T. Formation mechanism of eco-geo-environmental hazards in the ago-pastoral interlocking zone of northern China. Environmental Geology. 2000, 39 (12): 1385-1390.
[63] Diddle, M. J. A selective review of the ecological effects of human trampling on natural ecosystems. Biological Conservation. 1975, 7:17-36.
[64] Donkor, N.T.; Bork, E. W. and Hudson, R. J. Bromus-Poa response to defoliation intensity and frequency under three soil moisture levels. Canadian Journal of Plant Science.2002, 82(11):365-370.
[65] Dormaar, J. F.; Adams, B. W.; Willms, B. D. 1994. Effects of grazing and abandoned cultivation on a Stipa-Bouteloua community, J. Rage. Manage. 1994, 47:28-32.
[66] Dormaar, J. F.;Smoliajk, S. Seasonal variation in chemical characteristics of soil organic matter of grassland, d. Range Manage. 1977, 30:195-198.
[67] Drewry, J. J. and R. J. Paton. Effects of sheep treading on soil physical properties and pasture yield of newly sown pastures. New Zealand Journal of Agricultural Research.2005, 48:39-46.
[68] Dumont B., Boissy A. Grazing behaving of sheep in a situation of conflict between feeding and social motivations. Behavioural Processes.2000, 49:131-138.
[69] Dyer, M. I. The effects of Red winged Blackbirds (Agelaius phoeniceus L.) on biomass production of corn grains (Zea mays L.). Journal of Applied Ecology. 1975, 12:719-726.
[70] Dyer, M. I.;U. G. Bokhari. Plantanimal interactions: studies of the effects of grasshopper grazingn in blue grama grass. Ecology. 1976, 57:762-772.
[71] E. Klaghofer. 农业措施对地表径流和土壤侵蚀的影响．水土保持科技情报．1999，2：1-3．
[72]Edyy, M. and Argenta, T. Aboveground and belowground biomass relations in steppes under different grazing conditions.Oikos. 1989, 56:364-370.
[73]Eldridge, D.J.; Greene, R.S.B. Microbiotic soil crusts: a review of their roles in soil and ecological processes in the rangelands of Australia. Australian Journal of Soil Research. 1994,32:389-415.
[74]Eldridge, D.J.; Zaady, E.; Shachak, M. Microphytic crusts, shrub patches and water harvesting in the Negev Desert: the Shikim system. Landscape Ecology.2002,17(6):587-597.
[75]Eldridge, D.J; Koen, T.B. Cover and floristics of microphytic soil crusts in relation to indices of landscape health. Plant Ecology. 1998,137(1):101-114.
[76]Ellison, L. The influence of grazing on plant sucession . Botanical Review.1960,26:1-78.
[77]Evans,R. The erosional impacts of grazing animals. Progress in Physical Geography. 1998, 22(2):251-268.
[78]Fay,P.A.; Carlisle J.D.; Knapp, A.K.; Blair, J.M. and Collins, S.L. Productivity responses to altered rainfall patterns in a G_4-dominated grassland. Oecologia.2003, 137:245-251.
[79]Finlayson, J.D.; Betteridge, K.; MacKay, A.; Thorrold, B.; Costall, D.A. A simulation model of the effects of cattle treading on pasture production on Northern Island, New Zealand, hill land. New Zealand Journal of Agricultural Research.2002,45(2):255-272.
[80]Francis GS, Tabley FJ, White KM. Soil degradation under cropping and its influence on wheat yield on a weekly structured New Zealand silt loam. Australian Journal of Soil Research.2001, 39(2):291-305.
[81]Frank, A .B.; Tanakn, D.L. and Follett, R. E. Soil carbon and nitrogen of Northern Great plain grasslands as influenced by long-term grazing. Journal of Range Management. 1995,48(6):528-534.
[82]Frank, D. A.; Evans, R. D. Effects of native grazers on grassland N cycling in Yellewstone National Park. Ecology.1997, 78(7):2238-2248.
[83]Frank,D.A.; Groman,P.M. Denitrification in a semi-arid grazing cosystem. Oecologia. 1998,117:564-569.
[84]Franzluebbers A.J., Stueddemann J.A., Stueddemann J.A., Schomberg H.H. Spatial distribution of soil biochemical properties under grazed tall fescue. Soil Science Society of America Journal. 2000, 64:635-639.
[85]Fryrear, D. W. Soil cover and wind erosion. Trans. ASAE.1985,28(3):781-784.
[86]Fullen, M. A. Effects of grass ley set aside on runoff, erosion and soil organic matter levels in sandy soils in east Shropshire, UK. Soil & Tillage Research.1998, 46:41-49.
[87]Gallet S. and Roze F. Long-term effects of trampling on Atlantic Heathland in Brittany France: resilience and tolerance in relation to season and meteorological conditions. Biological Conservation.2002, 103: 267-275.
[88]Gallet, S., and F. Roze. Resistance of Atlantic Heathlands to trampling in Brittany (France): Influence of vegetation type, season and weather conditions. Biological Conservation.2001, 97:189-198.
[89]Gallet, S.; Lemauviel,S. and Rose, F.O. Responses of Three Heathland Shrubs to Single or Repeated Experimental Trampling. Environmental Management..2004, 33(6):821-829.
[90]Gao, X. J.; Zhao, Z. C.; and Ding, Y. H. Climate Change due to Greenhouse Effects in China as Simulated by a Regional Climate Model. Advances in Atmospheric Sciences. 2001,18:1224-1230.
[91]Gebeyehu, S.; Samways, M.J.Grasshopper assemblage response to a restored national park; Mountain Zebra National Park, South Africa. Biodiversity and Conservation. 2002, 11(2):283-304.
[92]Gibson, C. W. D.; Brown, V. K. Grazing and vegetation changes: deflected or modified succession ? Journal of Applied Ecology. 1992, 5 (29): 120-131.
[93]Gijsman, A.J. and Thomas, R.J. Evaluation of some physical properties of an oxisol after conversion of native Savanna into legume-based on pure grass pastures. Trop. Grasslands. 1996, 30:237-248.
[94]Gillingham, M.P.; Parker, K.L.; Hanley, T.A. Forage intake by black-tailed deer in a natural environment: bout dynamics. Canadian Journal of Zoology. 1997, 75(7): 1118-1128.
[95]Grace, J. B. On the measurement of plant competieiton intensity. Ecology. 1995, 76(1): 305-308.
[96]Graetz D. Grasslands. In: Changes in Land Use and Land Cover: a Global Perspective (eds W. B. Meyer & B. L. Turner, Ⅱ), pp. 125-147. Cambridge: Cambridge University Press. 1994.
[97]Greene,R.S.B.;Kinnell,P.I.A.;Wood,J.T. Role of plant cover and stock trampling on runoff and soil erosion from semi-add wooded rangelands. Aus.J.Soil Res. 1994, 32:953-973.
[98]Greenwood, EB.; Mcnamara, R.M. An analysis of the physical condition of two intensively grazedSouthland soils. Proceedings of the New Zealand Grassland Association. 1992, 54:71-75.
[99]Greenwood, P.B.;Macleod, D.A. and Hutchinson,K.J. Long-term stocking rate effects on soil physical properties. Australian. J. of Experimental Agriculture.1997, 37:413-419.
[100]Grime, J. P. Competitive exclusion in herbaceous vegetation. Nature. 1973, 242:344-347.
[101]Grime, J. P. Evidence for the existence.of three primary strategies in plants and its relevance to ecological and evolutionary theory, American Naturalist. 1977, 111:1169-1194.
[102]Gross K.L., Willig M.R., Gough l., Inouye R., Cox S.B. Patterns of species diversity and productivity at different spatial scales in herbaceous plant communities. Oikos. 2000, 89:417-427
[103]Guerif, J. Factors influencing compaction-induced increases in soil strength. Soil & Tillage Reaserch. 1990, 16:167-178.
[104]Guethery, F. S. and Bingham, R. L. A theoretical basis for study and management of trampling cattle. J. Range. Manage.1996,49:264-269.
[105]Hadwen,S. and Palmer, L. J. Reindeer in Alaska. USDA Bulletin. No. 1089. Washington, D. C.: US Department of Agriculture. 1922.
[106]Hall, D. O.;Ojima, D.S.;Parton, W.J. and Scuilock, J.M.O. Response of temperate and tropical grasslands to CO_2 and climate change, Journal of Biogeography. 1995,22:537-547.
[107]Hansson, A.C. and Andren, O. Below-ground plant production in a perennial grass ley assessed with different methods. J. of Appl. Ecol. 1986, 23:56-67.
[108]Harper, J.L. Population Biology of Plants. Academic Press, London. 1977.
[109]Harris, R.A.; Jones, R.M.; Rook, A.J.; Penning, P.D. The Loft and Hill of White Hamars Grazing Project. In Penning PD (ed.): Proceedings of the British Grassland Society Conference. 2000,157-158.
[110]Hart, R.H. A simple model to assess range technology. J. Range Manage. 1989, 42:421-424.
[111]Hart, R.H.; Bissio, J.; Samuel, M.J. and Waggoner, J. W. Grazing systems, pasture size, and cattle grazing behavior, distribution and gains. J. Range Manage. 1993a, 46:81-87.
[112]Hart, R.H.; Clapp, S. and Test, P. S. Grazing strategies, stocking rates, and frequency and intensity of grazing on western wheatgrass and bluegrass. J. Range Manage. 1993b, 46:122-126.
[113]Hart, R.H.; Samuel, M. J.; Test, P. S. and Smith, M. A. Cattle, vegetation and economic responses to grazing systems and grazing pressure. J. Range Manage. 1988,41:282-286
[114]Hartge,K.H. Stress distribution in the solid phase of soils.Soil Technology. 1993,6:83-87.
[115]Hassell, M.P. and Wilson, H.B. The dynamics of spatially distributed host-parasitoid systems. In: D. Tilman and P. Kareiva (eds), Spatial Ecology: the Role of Space in Population Dynamics and Interspecific Interactions. Princeton University Press, Princeton, pp.75-110.1997.
[116]Hertz,J.A.;Krogh,A.S.;Palmer,R.G Introduction to the Theory of Neural Computation. Addison Wesley, Redwood City, CA.,1991. p115-162,217-227.
[117]Hiernaux P, Bielders CL, Valentin C, Bationo A, Fernandez Rivera S. Effects of livestock grazing on physical and chemical properties of sandy soils in Sahelian rangelands. Journal of Arid Environments. 1999,41(3):231-245.
[118]Hill, M. O.; Evans, D. F.; Bell, S. A. Longterm effects of excluding sheep from hill pastures in North Wales. Journal of Ecology. 1992 , 80:1-13.
[119]Hillel, D. Soil and Water: Physical Principles and Processes. 1971.
[120]Hobbs, R. J. Disturbances as a precursor for weed invasion in native vegetation. Plant Protection Quarterly.1991,8:99-104.
[121]Hodgson J. Grazing Managemnt- Science into Practice. New York :Longman Science and Technical Press. 1990.
[122]Hodgson, J.; Illius, A. W. The ecology and management of grazing systems. CABI, Oxon, UK, 1995.
[123]Holland, E. A.; Detling, J. K. Plant-response to herbivory and belowground nitrogen cycling. Ecology. 1990,71:1040-1049.
[124]Holt, J. A. Grazing pressure and soil carbon, microbial biomass and enzyme activities in semi-arid northeastern Australin.Appl.. Soil Ecol. 1997,5:143-149.
[125]Holt, J.A.; Bristow, K.L and McIvor, J.G The effects of grazing pressure on soil animals and hydraulic properties of two soils in semi-arid tropical Queensland. Aust. J. Soil Res. 1996,34:69-79.
[126]Hood, L.; Morgan, J.K. Whose home on the range? Sierra Club Bull. 1972, 57:4-11.
[127]Hopkins, A. and Wainwright, J. Change in botanical composition and agricultural management of enclosed grass land in upland areas of England and Wales, 1970-1986, and some conservation implications. Biological Conservation.1989,47:219-235.
[128]Horgan, G.W. Mathematical morphology for analyzing soil structure from images. European Journal of Soil Science. 1998, 49:161-173.
[129]Horn, R.; Domzal, H.; Slowinska-Jurkiewicz, A. and Ouwerkerk, C. Soil compaction processes and their effects on the structure of arable soils and the environment. Soil Till. Res. 1995, 35:23-36.
[130]Huang Chihua, Zheng Fenli. Research Progress on Soil Erosion Process and Erosion Predction Model in the USA.水土保持通报.2003,23(3): 1-5.
[131]Hui Long Lin, Qi Ming Zhuang. Adaptive extent and seed yield predictions for Microula sikkimensis grown in the Qinghai-Tibet Plateau, China. Ecological modelling 201 (2007) 507-520.
[132]Huilong LIN, Jizhou REN, and Qin WANG. Seed yield predictions based on the habitat niche-fitness of Microula sikkimensis, an endemic oil crop in the Qinghai-Tibet Plateau. Botanical Studies.2006,47: 291-306.
[133]Hunt, L.P. Low seed availability may limit recruitment in grazed Atriplex vesicaria and contribute to its local extinction. Plant Ecology. 2001, 157(1):53-67.
[134]Hylgaard,T.and Liddle,M.J. The effect of human trampling on a sand dune ecosystem dominated by Empetrum nigrum. Journal of Applied Ecology.1981, 18:559-569.
[135]Ian, J. R.; Benjamin, F. T. Disturbance persistence in managed grasslands: shifts in aboveground community structure and the weed seed bank. Plant Ecol.2006. DOI 10.1007/s11258-006-9191-7.
[136]Ikeda, H. and Okutomi, K. Effects of human trampling and multispecies competition on earlyphase development of a tread community. Ecological Research. 1990, 5:41-54.
[137]Ikeda, H. and Okutomi, K. Effects of species interactions on community organization along a trampling gradient. Journal of Vegetation Science. 1992, 3:217-222.
[138]Ikeda, H. and Okutomi, K. Effects of trampling and competition on plant growth and shoot morphology of Plantago, Eragrostis and Eleusine species. Acta Botanica Neerlandica. 1995, 44:151-160.
[139]Ikeda, H. Testing the intermediate disturbance hypothesis on species diversity in herbaceous plant communities along a human trampling gradient using a 4-year experiment in an old-field. Ecological Research.2003, 18:185-197.
[140]Imhoff, S.; Pires da Silva, A. and. Tormena, C.A Spatial heterogeneity of soil properties in areas under elephant-grass short-duration grazing system. Plant and Soil.2000, 219:161-168.
[141]Ingram, K.T. and Leers, GA. Software for measuring root characters from digital images.Agron.J.2001, 93:918-922.
[142]Jackson, L.L. Establishing tallgrass prairie on grazed permanent pasture in the Upper Midwest. Restoration Ecology.1999, 7(2):127-138.
[143]Jeffries, D. L. and Klopatek, J. M. Effects of grazing on the vegetation of the blackbrush association.J Range Manag. 1987, 40:390-392.
[144]John Frame. Improved grassland management. United Kingdom: Fanning Press.2000.
[145]John,C. C.and Joy,B.Z. Restoration of urban salt marshes: Lessons from southern California. Urban Ecosystems.2004, 7:107-124.
[146]Johnston, A.; Dormmar,J. F.; Smoliak, S. Long-term grazing effects on fescue grassland soils. Journal of Range Management. 1971, 24:185-188.
[147]Jordan, D.; Ponder, F.; Hubbard, V. C. Effects of soil compaction, forest leaf litter and nitrogen fertilizer on two oak species and microbial activity. Appl. Soil Ecol.2003, 23:33-41.
[148]Keller, A. A.; Goldstein, R. A. Impact of carbon storage through restoration of dry lands on the global carbon cycle. Environ. Manage. 1998, 22:757-766.
[149]Kemper, J.; Cowling, R.M.; Richardson, D.M. Fragmentation of South African renosterveld shrublands: effects on plant community structure and conservation implications. Biological Conservation.1999, 90(2): 103-111.
[150]Kepner, W.G.; Watts, C. J.; Edmonds, C. M.;Maingi, J.K.; Marsh, S.E.;Luna, G. A Landscape approach for detecting and evaluating change in a semi-arid environment. Environmental Monitoring and Assessment.2000, 64:179-195.
[151]Kim, J.G. The effects of cattle grazing on optimal foraging in mule deer (Odocoileus hemionus).Forest Ecology and Management. 1996, 88(1/2): 131-138.
[152]Kirkby, M.J.;Morgan,R.P.C. Soil erosion. John Wiley & Sons Ltd. 1980.
[153]Kleiner, E. F. & Harper, K. T. Soil properties in relation to cryptogamic ground cover in Canyonlands National Park. J. Range Manag. 1977, 30:203-205.
[154]Kobayashi, T.; Hori, Y. and Nomoto, N. Effects of trampling and vegetation removal on species diversity and microenvironment under different shade conditions. Journal of Vegetation Science.1997, 8(6): 873-880.
[155]Koc, A., Oztas, T., Tahtacioglu, L. Rangeland-livestock interaction in our near history: problems and recommendations. Proceedings of the International Symposium on Desertification, 13-17 June 2000, Konya, Turkey, pp.293-298.
[156]Kohler, F. Influence of grazing, dunging and trampling on short-term dynamics of grasslands in mountain wooded pasture. PhD Thesis, University of Neuchatel, Neuchatel, 2004.
[157]Kohler, F.; Gillet, F.; Gobat, J. M.; Buttler, A. Seasonal vegetation changes in mountain pastures due to simulated effects of cattle grazing. J. Veg. Sci.2004, 15:143-150.
[158]Kohler, F.; Hamelin, J.; Gillet, F.; Gobat, J.M.; Buttler, A. Soil microbial community changes in wooded mountain pastures due to simulated effects of cattle grazing. Plant and Soil.2005, 278:327-340.
[159]Koutika, L. S.; Andreux, F.; Hassink, J. Charactertration of organic matter in the topsoils under rain forest and pastures in the eastern Brazilinn Amazon basin. Biol. Fertil. Soils. 1999, 29:309-313.
[160]Kutiel P., Eden E. and Zhevelev Y. Effect of experimental trampling and off-road motorcycle traffic on soil and vegetation of stabilized coastal dunes, Israel. Environmental Conservation.2000, 27(1): 14-23.
[161]Lal, R. World soils and greenhouse effect. IGBP Global Change News letter.1999, 37:4-5.
[162]Lal, R.; Stewart, B.A. Soil degradation. New York: Springer-Verlag. 1990.
[163]Laska,G. The disturbance and vegetation dynamics: a review and an alternative framework. Plant Ecology. 2001,157: 77-99.
[164]Lauenroth, W.K. and Whitman, W.C. A rapid method for washing roots. J. Rang. Mang.1971, 24:37-42.
[165]Laycock W.A. and Conrad P.W. Effect of grazing on soil compaction as measured by bulk density on a high elevation cattle range. Journal of Range anagement. 1967, 20:136-140.
[166]Le Roux, X.; Bardy, M.; Loiseau, P.; Louault, F. Stimulation of soil nitrification and denitrification by grazing in grasslands: do changes in plant species composition matter? Oecologia.2003,137:417-425
[167]LeCain, D. R.; Morgan, J. A.; Schuman, G. E. Carbon exchange and species composition of grazed pastures and exclosures in the shortgrass steppe of Colorado. Agricultures Ecosystems & Environment. 2002, 93:421-435.
[168]Lehmann, A., Leathwick, J.R., Overton, J.McC., Assessing New Zealand fem diversity from spatial predictions of species assemblages. Biodivers. Conserv.2002a, 11:2217-2238.
[169]Lehmann, A; J. M.Overton and J. R. Leathwick. GRASP: generalized regression analysis and spatial prediction. Ecological Modelling.2002b, 157:189-207.
[170]Lemauviel, S., and F. Roze. Response of three plant communities to trampling in sand dune systems in Brittany (France). Environmental Management.2003, 31:227-235.
[171]Liddle M.J. A selective review of the ecological effects of human trampling on natural ecosystems. Biological Conservation. 1975, 7:17-36.
[172]Liddle M.J. Recreation Ecology. London: Chapman and Hall. 1997.
[173]Liddle, M. J. Recreation ecology: effects of trampling on plants and coral. Trends in Ecology and Evolution.1991, 6:13-17.
[174]Liddle, M. J. A selective review of the ecological effects of human trampling on natural ecosystems. Biological Conservation. 1975a, 7:17-36.
[175]Liddle, M. J. A theoretical relationship between the primary productivity of vegetation and its ability to tolerate trampling. Biological Conservation.1975b, 8:251-255.
[176]Liddle, M. J. and Barker, S. The ecological response of forest ground flora and soils to experimental trampling in British urban woodlands. Urban Ecosystems.2001, 5:257-276.
[177]Liddle,M.J. and Thyer,N,C.Trampling and fire in a subtropical dry sclerophyll forest.Environmental Conservation. 1986,13:33-39.
[178]Littlemore, J. Resolving conflicts between recreation and conservation in Britain's urban woodlands—a management guide. Quarterly Journal of Forestry.2001,95(2): 129-136.
[179]Lock,J.M. The effects of hippopotamus grazing on grasslands. Journal of Ecology. 1972,60:445-467.
[180]Malcolm B, Sale P, Egan A. Agriculture in Australia: an introdution. Melbourne: Oxford University Press. 1996,391-419.
[181]Malinda, D.K.; Facett, R.G.; Little, D.; Bligh, K. Darling, W. The effect of grazing, surface cover and tillage on erosion and nutrient depletion. Advances in Geoecology.1998, (31): 1217-1224.
[182]Malthus, R. Essay on the Principle of Population. Mew York: Phillip Applemaned. Norton, 1798. Reprinted 1976.p226.
[183]Mandelbrot, B.B. The Fractal Geometry of Nature. W H Freeman, New York, 1982.
[184]Maria, B. M.; Nilda, M. A.; Norman, P. Soil degradation related to overgrazing in the semi-arid southern Caldenal area of Argentina. Soil Science. 2001, 166 (7):441-452 .
[185]Maria, F.G.; Barbara, A.D. Vegetation change along gradients from water sources in three grazed Mongolian ecosystems. Plant Ecology..2001, 157( 1): 101 -118.
[186]Marion,J.L.and Cole, D.N. Spatial and temporal variation in soil and vegetation impacts on campsites'. Ecological Applications.1996, 6(2):520-530.
[187]Maron J.L.and Gardner, S.N.Consumer pressure, seed versus safe-site limitation, and plant population dynamics. Oecologia.2000, 124:260-269.
[188]Marshall, J.K. Drought, land use and soil erosion. In: Lovett, J.V. (Ed.), In the Environmental, Economic and Social Significance of Drought. Angus and Robertson Publ., Inc., London, 1973.pp. 55-77.
[189]Martin, K; Ralf, C. Effect of CH_4 concentrations and soil conditions on the induction of CH_4 oxidation activity . Soil Biology and Biochemistry, 1995,27:1517-1527.
[190]Martinez, L. J.; Zinck, J. A. Temporal variation of soil compaction and deterioration of soil quality in pasture areas of Colombian Amazonia. Soil Till. Res.2004,75, 3-17.
[191]Mayer, A.C.; Stocklil, V.; Konold, W.; Kreuzer, M. Influence of cattle stocking rate on browsing of Norway spruce in subalpine wood pastures. Agroforestry Systems.2005, 34:33-41.
[192]McCalla, G.R.; Blackburn, W.H.and Merrill,L.B. Effects of livestock grazing on infiltration rates, Edwards Plateau of Texas. J. Range Manage.1984, 37:265-269.
[193]McConnell, S. G.; Quinn, M. L. Soil productivity of four land use systems in southeastern Montana. Soil Science Society of America Journal.1988, 52:50-56.
[194]Mclntire, E. J. B.; Hik, D. S. Grazing history versus current grazing: leaf demography and compensatory groeth of three alpine plants in response to a native herbivore (Ochotona collaris). Journal of Ecology. 2002,90(2):348-359.
[195]McNaughton, S. J. Compensatory plant growth as a response to herbivory. Oikos.1983,40:329-336.
[196]McNaughton, S. J. Grazing as an optimisation process: grassungulate relationships in the Serengti. American Naturalist. 1979, 5:691-703.
[197]McNaughton, S. J. Serengeti migratory wildebeest facilitation of energy flow by grazing.Science. 1976,191: 92-94.
[198]McNaughton, S. J.; F. S.Chapin. Effects of phosphorus nutriton and defoliation on C4 graminoids from the Serengeti plants. Ecology. 1985, 66:1617-1629.
[199]McNaughton, S.J. Ranyikwa, F.F., and McNaughton, N.M. Root biomass and productivity in grazing ecosystem: the Sorengeti.Ecology.1998, 79(2):587-592.
[200]Meyer, L. D. Evolution of the Universal Soil Loss Equation. J. Soil and Water Cons. 1984, 32(2):99-104.
[201]Milchunas, D. G.; Laurenorth, W. K. Quantitative effects of grazing on vegetation and soils over a global range of environments. Ecological Monographs. 1993, 63(4):327-366.
[202]Milchunas, D. G.; Sala, O. E. and Lauenroth, W. K. A generaltred model of the effects of grazing by large herbivores on grassland community structure. American Naturalist.1988, 132:87-106.
[203]Mitchell, C .A.; Custer, T. W.; Zwank, P. J. Herbivore on short grass by wintering redheads in Texas. Journal of Wildlife Management.1994, 58:131-141.
[204]Monz, C. A. The responses of two arctic tundra plant communities to human trampling disturb bance.Journal of Environmental Management. 2002, 64:207-217.
[205]Morgan, R. P. C.; Quinton, J. N.; Smith, R. E.. The European Soil Erosion Model (EU ROSEM ): A dynamic approach for predicting sediment transport from fields and small catchments. Earth Surface Processes and Land forms..1998,23(6):527-544.
[206]Murphy, W. M.; Barreto, A. D.; Silman, J. P. and Dindal, D. L. Cattle and sheep grazing effects on soil organisms, fertility and compaction in a smooth-stalked meadowgrass-dominant white clover sward. Grass Forr. Sci.1995, 50:191-194.
[207]Mwendera, E.J.; Saleem, M.A.M. Hydrologic response to cattle grazing in the Ethiopian highlands. Agric Ecosyst Environ. 1997, 64:33-41.
[208]Naeth, M. A.; Bailey, A. W.; Pluth, D. J.. Grazing impacts on litter and soil organic matter in mixed prairie and fescue grassland ecosystems of Alberta. J. Range Manage. 1991,44(1):7-12.
[209]Nash, T. H., White, S. L. & March, J. E. Lichen and moss distribution and biomass in hot desert ecosystems. Bryologist. 1977, 80:470-479.
[210]Nearing, M. A.; Foster, G. R.; Lane, L. J., A process-based soil erosion model for USDA-Water Erosion Prediction Project Technology. Trans.ASAE. 1989, 32:1587-1593.
[211]Nguyen, M.L.; Sheath, G.W.; Smith, C.M.; Cooper, A.B. Impact of cattle treading on hill land, 2. soil physical properties and contaminant runoff. New Zealand Journal of Agricultural Research.1998, 41(2):279-290.
[212]Ni, J.Carbon storage in grasslands of China. Journal of Arid Environmenis.2002, 50:205-218.
[213]Nie, Z.N.; Mackay, A.D.; Valentine, I.; Barker, D.J. and Hodgson, J. Influence of pastoral fallow on plant root growth and soil physical and chemical characteristics in a hill pasture. Plant and Soil.1997,197: 201-208.
[214]Noble, I. R., and R. O. Slatyer. The use of vital attributes to predict successional changes in plant communities subject to recurrent disturbances. Vegetatio.1980, 43:5-21.
[215]Olff, H.; Vera, F. W. M.; Bokdam. J.; Bakker, E. S.; Gleichman, J. M.; de Maeyer, K. and Smit, R. Shifting mosaics in grazed woodlands driven by the alternation of plant facilitation and competition. Plant Biol. 1999,1:127-137.
[216]Olson and Wischmeier. Soil erodibility evaluation for soils on the runoffand erosion stations.Soil Science. 1963, 27 (5):590-592.
[217]Orr H.K. Soil porosity and bulk density on grazed and protected bluegrass range in the Black Hills. Journal of Range Management.1960, 13:80-86.
[218]Owen, D. F.; R. G. Wiegert. Do consumers maximise plant fitness.Oikos. 1976, 27:488-492.
[219]Owen, D. F.; R. G. Wiegert. Mutualism between grasses and grazers: an evolotionary hypothesis. Oikos. 1981, 36:376-378.
[220]Owens，L．B．牧地围栅对径流泥沙的影响．水土保持科技情报．1996，3：36—38．
[221]Oztasa, T.; Kocb,A.; Comakli, B. Changes in vegetation and soil properties along a slope on overgrazed and eroded rangelands. Journal of Arid Environments.2003, 55:93-100.
[222]Pakeman RJ, Thwaites RH, Duc MG le, Marrs RH. Vegetation re-establishment on land previously subject to control of Pteridium aquilinum by herbicide. Applied Vegetation Science.2000, 3(1):95-104.
[223]Perevoznikova, V. D. and Zubareva, O. N. Geobotanical Indication of the State of Suburban Forests. Russian Journal of Ecology.2002, 33 (1): 1-6.
[224]Perfect, E.; Kay, B.D. Fractal theory applied to soil aggregation. Soil Sci Soc Am J. 1991, 55:1552-1558.
[225]Perfect, E.; Rasiah, V.; Kay, B.D. Fractal dimensions of soil aggregate—size distributions calculated by number and mass. Soil Sci Soc Am J. 1992, 56:1407-1409.
[226]Perfect, E; Kay, B.D.; Rasiah, V. Multifractal model for soil aggregate fragmentation. Soil Sci Soc Am J. 1993, 57: 896-900.
[227]Peter, B. A. and Sonia, A. H. The development of forage production and utilization gradients around livestock watering points. Landscape Ecology .2005,20:319-333.
[228]Pimentel, D. (ed.). World soil erosion and conservation. Cambridge: Cambridge University Press. 1993.
[229]Pimentel, D.; Harvey, C.; Resosudarmo, P.; Sinclair, K.; Kurz, D.; McNair, M.; Crist, S.; Sphpritz, L.; Fitton, L.; Saffouri, R.; Blair, R. Environmental and economic costs of soil erosion and conservation benefits. Science. 1995,267:1117-1123.
[230]Pimentel, D.and Kounang, N. Ecology of Soil Erosion in Ecosystems. Ecosystems.1998, 1:416-426.
[231]Priskin,J. Tourist Perceptions of Degradation Caused by Coastal Nature-Based Recreation. Environmental Management.2003, 32(3): 189-204.
[232]Proffitt, A. P. B.; Bendotti, S.; McGarry, D. A comparison between continuous and controlled grazing on a red duplex soil. 1. Effects on soil physical characteristics. Soil & Tillage Research.1995, 35:199-210.
[233]Proffitt, A.P.B.; Jarvis, R.J. and Bendotti, S. The impact of sheep trampling and stocking rate on the physical properties of a red duplex soil with two initially different structures. Australian Journal of Agricultural Research.2005,46(4):733-747
[234]Rasanen, S. Tracing and interpreting fine-scale human impact in northern Fennoscandia with the aid modern pollen analogues. Vegetation History and Archaeobotany.2001, 10(4):211-218.
[235]Rasiah, V.; Kay, B.D.; Perfect, E. Evaluation, of selected factors influencing aggregate fragmentation using fractal theory. Canada J Soil Sci.1992, 72:97-106.
[236]Rasiah, V.; Kay, B.D.; Perfect, E. New mass based model for estimating fractal dimensions. Soil Sci Soc Am J.1993,57:891-895.
[237]Reeder,J .D.; Gerald, E. Schuman,G.E.; Morgan,J.A.; Lecain,,D.R. Response of Organic and Inorganic Carbon and Nitrogen to Long-Term Grazing of the Shortgrass Steppe. Environmental Management. 2004, 33(4):485-495.
[238]Reeder,J .D.; Schuman, G. E. Influence of livestock grazing on C sequestration in semi- arid mixed-grass and short-grass rangelands.Environment Pullution.2002, 116:457-463.
[239]Renard, K.G.; Foster,G.R.; Weesies, G.A. Predicting soil erosion by water: A guide to conservation planning with the Revised Universal Soil Loss Equation(RUSLE). Agricultural Handbook No.537, United States Department of Agriculture, Washington. 1997.
[240]Rezende, C. P.; Cantarutti, R.B.; Braga, J.M.; Gomide, J.A.; Pereiral, J.M. ; Ferreira, E. ; Tarr'e, R.; Macedo, R.; Alves, B.J.R.; Urquiaga, S.; Cadisch, G.; Giller, K.E. and Boddey, R.M. Litter deposition and disappearance in Brachiaria pastures in the Atlantic forest region of the South of Bahia, Brazil. Nutrient Cycling in Agroecosystems.1999, 54:99-112.
[241]Ritche, M.E. Herbivore effects on plant and nitrogen dynamics in oak savanna.Ecology.1998, 79(1): 165-177.
[242]Rodgers,K.;Cox,E. and Newtson,C.Effects of mechanical fracturing and experimental trampling on Hawaiian Corals. Environmental Management .2003, 31(3):377-384.
[243]Rogers, R. W. & Lange, R. T. Lichen populations on arid soil crusts around sheep watering places in South Australia. Oikos.1971, 22:93-100.
[244]Romulo, S. C. M.; Edward, T .E.; David, W. V.; Stephen, A. W. Carbon and nitrogen dynamics in elk winter ranges. Journal of Range Management.2001, 54:400-408.
[245]Roovers,P.; Baeten,S. and Hermy,M. Plant species variation across path ecotones in a variety of common vegetation types. Plant Ecology.2004, 170:107-119.
[246]Roux, X.L.; Bardy, M.; Loiseau, P.; Louault, F. Stimulation of soil nitrification by grazing in grasslands: do changes in plant species composition matter? Oecologia.2003, 137(3):417-425.
[247]Sada, D.W. Demography and habitat use of the Badwater snail (Assiminea infima), with observations on its conservation status, Death Valley National Park, California, U.S.A. Hydrobiologia.2001,466: 255-265.
[248]Sampson, A. W. Range and Pasture Management. New York: John Wiley & Sons. 1923. p328.
[249]Savory, A. and Parson, S. D. The Savory grazing method. Rangeland 1980, (2):234-237.
[250]Savory, A. Holistic Resource Management. Covel, Calif: Island Press. 1988
[251]Savory, A. The Savory grazing method or holistie resource mangement. Rangeland. 1983, (5): 155-159.
[252]Schimel, D.; House, J. Hibbard, K. Recent patterns and mechanisms of carbon exchange by terrestrial ecosystems. Nature.2001,414:169-172.
[253]Schlaepfer, M.; Zoller, H.; Koerner, C. Influences of mowing and grazing on plant species composition in calcareous grassland. Bot. Helv.1998, 108:57-67.
[254]Schlesinger, W.H. Carbon balance in terrestrial detritus.Annual Review on Ecological System.1977, 8:51-81.
[255]Schlesinger, W.H.Biogechemistry:an analysis of global change.San diego,California:Academic Press. 1997.pp:5-50.
[256]Schuman, G. E.; Reeder, J. D.; Manley, J. T. Impact of grazing management on the carbon and nitrogen balance of a mixed-grass rangeland. Ecological Applications. 1999,9(1):65-71.
[257]Scurlock, J.M.O.;Johnson, K.;Qlson. R.J. Estimating net primary productivity from grassland biomass dynamics measuremenis. Gobal Change Biolog.2002, 8:736-753.
[258]Scurlock, J.M.O.;Hall, D.O.The global carbon sink: a grassland perspective. Gobal Change Biolog. 1998, 4:229-233.
[259]Seitlheko, E.M.; Allen, B.L.; Wester, D.B. Effect of three grazing intensities on selected soil properties in semi-arid west Texas. African Journal of Range and Forage Science.1993, 10(2):82-85.
[260]Shao, Y. P.; Raupach, M. R.; Leys, J. F. A model for predicting Aeolian sand drift and dust entrainment on scales from pad-dock to region. Australian Journal of Soil Research.1996, 34:309-342.
[261]Shariff, A.R.; Biondini, M. E.; Grygiel, C. E. Grazing intensity effects on litter decomposition and soil nitrogen mineralization. J.of Range Management. 1994, 47:444-447.
[262]Sharply, A. N.; J. R. Williams. EPIC-Erosion/Productivity Impact Calculator: 1. Model Documentation. US Department of Agriculture Technical Bulletin, No. 1968, 1990.
[263]Sheldrick, B.H.; Wang, C. Particle size distribution. In: Carter, M.R.(eds). Soil Sampling and Methods of Analysis. Canadian Society of Soil Science. Boca Raton, FL: Lewis Publishers, Division of CRC Press. 1993,p499-511;
[264]Silva, A.P.; Imhoff, S.; Corsi, M. Evaluation of soil compaction in an irrigated short-duration grazing system. Siol and Tillage Research.2003, 70(1):83-90.
[265]Society for Range Management. A Glossary of Terms Used in Range Mangement. Edison Press, Denver, Colorado, USA: Society For Range Management. 1964.p1-24.
[266]Society for Range Management. A Glossary of Terms Used in Range Mangement. 3rd edition. Complied by Jacoby,P.W. Edison Press, Denver, Colorado,USA:Society For Range Management, 1989.p1-36.
[267]Sperber, T.D.; Wraith, J.M. and Olson, B.E. Soil physical properties associated with the invasive spotted knapweed and native grasses are similar. Plant and Soil.2003, 252:241-249.
[268]Steen, E.Root biomass in timothy and red clover leys estimated by soil corning and mesh bags.J. of Agri.Sci. 1989,113:578-580.
[269]Stephenson, G.R.; Veigel, A. Recovery of compacted soil on pastures used for winter cattle feeding. Journal of Range Mangement. 1987,40(1):253-257.
[270]Sun, D. and Liddle, M. J. A survey of trampling effects on vegetation and soil in eight tropical and subtropical sites. Environ. ManageA993a, 17:497-510.
[271]Sun, D. and Liddle, M. J. Field occurrence, recovery and simulated trampling resistance and recovery of two grasses. Biol. Conserv. 1991, 57:187-203.
[272]Sun, D. and Liddle, M. J.The morphological and the importance of tiller number in their resistance to trampling. Biol. Conserv. 1993b, 65:43-50.
[273]Sun, D., and D. Walsh. Review of studies on environmental impacts of recreation and tourism in Australia. Journal of Environmental Management.1998, 53:323-338.
[274]Sutherland,R.A.;Bussen,J.O.;Plondke,D.L.;Evans,B.M.;Ziegler,A.D. Hydrophysical degradation associated with hiking-trail use:A case study of Hawai'iloa ridge trail, O'ahu, Hawai'i. Land Degradation & development 2001, 12:71-86.
[275]Taddese,G.; Saleem, M. A. M.; Abyie. A. et al. Impact of grazing on plant species richness, plant biomass, plant attribute and soil physical and hydrological properties of Vertisol in East African Highlands. Environmental Management,.2002, 29(2):279-289.
[276]Talbot, L.M.; Turton S.M.; Graham A.W. Trampling resistance of tropical rainforest soils and vegetation in the wet tropics of north east Australia. Journal of Environmental Management. 2003,69 (1):63-69.
[277]Thomas,D.S.G. The biogeomorphology of arid and semi-arid environments.In:Viles, H.A.(Ed.), Biogemorphology. Blackwell, Oxford,1988,pp365.
[278]Tilman, D.; Downing, J.A. Biodiversity and stability in grasslands. Nature.1994, 5:363-367.
[279]Torn, M. S.; Trumbore, S. E.; Chadwick, O. A . Mineral control of soil organic carbon storage and turnover. Nature.1991, 389:170.
[280]Torn,A.;Rautio,J.;Norokorpi,Y. and Tolvanen,A. Revegetation after short-term trampling at Subalpine heath vegetation. Ann.Bot.Fennici.2006,43:129-138.
[281]Tureotte, D.L. Fractal fragmentation model of soil aggregation. J Geography Res.1993, 91(12):1896-1899.
[282]Turner, M. G. Effects of grazing by feral horses, clipping, trampling, and burning on a Georgia salt marsh. Estuaries. 1987,10:54-60.
[283]Tyler, S.W.; Wheatcraft, S.W. Application of fractal mathematics to soil water retention estimation. Soil Sci Soc Am J.1989, 153:987-996
[284]Tyler, S.W.; Wheatcraft, S.W. Fractal process in soil water retention. Water Resour Res. 1990a, 26:1047-1054.
[285]Tyler, S.W.; Wheatcraft, S.W. Fractal scaling of soil particle-size distributions: analysis and limitations. Soil Sci Soc Am J. 1990b, 56:362-369.
[286]Upchurch, D.R. and Ritchie, J.T. Root observations using a video recording system in minirhizotrons. Agron.J. 1983, 76:1009-1015.
[287]Wal, R.V.; Suzan, M.J.; van Lieshout, Maartent, J.J. Loonen, E Herbivore impact on moss depth, soil temperature and arctic plant growth. Polar Biology.2001, 24(1):29-32.
[288]Wallace L. L. Effects of clipping and soil compaction on growth, morphology, and mycorrhizal colonization of Schizachyrium scoparium, a C_4 bunch grass. Oecologia. 1987, 72:423-428.
[289]Wallace, L. L. Effects of clipping and soil compaction on growth, morphology, and mycorrhizal colonization of Schizachyrium scoparium, a C_4 bunch grass. Oecologia. 1993, 72:423-428.
[290]Wallsce, L; Dyer, M. I. Grassland management. Ecosystem maintenance and Grazing. In: Joern, T.; Keeler, K.(eds). The changing Prarie. Oxford Press,New york. 1995.
[291]Wang, X.; Dong, Z.B.; Zhang, J.W. and Liu, L.C. Modern dust storms in China: an overview. Journal of Arid Environments.2004, 58:559-574.
[292]Wang, Y. S.; Hu, Y. Q.; Ji, B. M.. An investigation on the relationship between emission/uptake of greenhouse gases and environmental factors in semiarid grassland. Advances in Atmospheric Sciences.2003, 20(1): 119-127.
[293]Wang, Y. S.; Ji, B. M.; Huang. Effects of grazing and cultivating on emission of nitrous oxide, carbon dioxide and uptake of methane from grasslands. Environmental Science.2001, 22(6):7-13.
[294]Warren, S. D.; Nevill, M. B.; Blackburn, W.H. and Garza, N.E. Soil response to trampling under intensive rotation grazing. Soil Science Society of America Journal. 1986, 50:1336-1341.
[295]Wasson, R. J.; Nanninga, P. M. Estimation wind transport sand on vegetated surface. Earth Surface Processes and Landforms.1986, 11:505-514.
[296]Waterman W.G. Development of root systems under dune conditions. Botanical Gazette. 1919, 68:22-53.
[297]Weaver J.E. and Bruner W.E. A seven-year quantitative study of succession in grassland. Ecological Monographs 1945, 15:298-319.
[298]Weaver J.E. and Darland R.W. A method of measuring vigor of range grasses. Ecology. 1947, 28:146-162.
[299]Weaver J.E. and Darland R.W. Soil-root relationships of certain native grasses in various soil types. Ecological Monographs 1949, 19:303-338.
[300]Weaver J.E. and Zink E. Annual increase of underground materials in three range grasses. Ecology. 1946a, 27:115-127.
[301]Weaver J.E. and Zink E. Length of life of roots often species of perennial range and pasture grasses. Plant Physiology. 1946b, 21:201-217.
[302] Weaver J.E. Investigation on the root habitats of plants. America Journal Botany. 1925, 12:502-509.
[303] Weaver J.E. Prairie Plants and their Environment: a fifty year study in the Midwest. University of Nebraska Press. 1968.
[304] Weaver J.E. Rate of decomposition of roots and rhizomes of certain range grasses in undisturbed prairie soil. Ecology. 1947,28:221-240.
[305] Weaver J.E. Summary and interpretation of underground development in natural grassland communities. Ecological Monographs. 1958b, 28:55-78.
[306]Weaver J.E., Hougen V.H. and Weldon M.D. Relation of root distribution to organic matter in prairie soil. Botanical Gazette. 1935a, 96:389-420.
[307] Weaver J.E., Jean F.C. and Crist J.W. Development and activities of roots of crop plants. Washington: Carnegie Inst. 1922.
[308]Weaver J.E., Stoddart L.A. and Noll W. Response of the prairie to the great drought of 1934. Ecology. 1935b, 16:612-629.
[309]Weaver J.E.. Classification of root systems of forbs of grassland and a consideration of their significance. Ecology. 1958a, 39:393-401.
[310]Weigel, J. R.; Britton, C. M. Mepherson, G R. Trampling effects from short- duration grazing on tobo sagrass range. Journal of Range management.1990,43(2):92-95.
[311]Westoby, M.; Walker, B.; Noy-meir. Opportunistic management for rangelands not at equilibrium. Journal of Range Management. 1989,42(4):266-274.
[312]Whalley, W. R.; Dumitru, E.; Dexter, A. R. Biological effects of soil compaction.Soil Till. Res.1995, 35:53-68.
[313]Whinam J. and Chilcott N. Impacts of trampling on alpine environments in central Tasmania. Journal of Environmental Management. 1999, 57:205-220.
[314]Whinam,J. and Chilcott,N.M. Impacts after four yeaers of experimental trampling in alpine/sub-alpine environment in western Tasmania. Journal of Environmental Management.2003,67:339-351.
[315]Whitecotton,R.C.A.;David,M.B.;Darmody,R.G. and Price,D.L. Impact of Foot Traffic from Military Training on Soil and Vegetation Properties. Environmental Management .2000,26(6):697-706.
[316]Wienhold, B. J.; Hendrickson, J. R.; Karn, J. F. Pasture management influences on soil properties in the Northern Great Plains. J. Soil and Water Conserv.2001, 56(1):27-31.
[317]Willatt, S.T. and Pullar, D. M. Changes in soil physical properties under grazed pastures. Aust. J. Soil Res. 1983.22,343-348.
[318] Winkel V K, Roundy B A, Blough D K. Effects of seedbed preparation and cattle trampling on burial of grass seeds. Journal of Range Management. 1991 a, 44(2): 171 -175.
[319]Winkel, V. K.; Roundy, B. A. Effects of cattle trampling and mechanical seedbed preparation on grass seedling emergence. Journal of Range Management. 1991b, 44(2): 176-180.
[320]Winter,S.R.; Unger, P.W. Irrigated wheat grazing and tillage effects on subsequent dryland grain sorghum production. Agronomy Journal. 2001,93(3):504-510.
[321]Wischmeier, W. H. Use and misused of the universal soil loss equation. J Soil and Water Cons. 1976, 31 (1):5-9.
[322]Wischmeier, W. H.; Smith, D. D. A universal soil loss equation to guide conservation farm planning. Soil Sci. 1960, 1:418-425.
[323]Wischmeier, W.H.; Smith, D.D. Predicting rainfall erosion losses.A guide to conservation planning. U. S. Department of Agriculture, Agriculture Handbook. 1978.
[324]Wischmeier, W.H.; Smith, D.D. Predicting rainfall- erosion losses from cropland east of the Rocky Mountains: A guide for selection of practices for soil and water conservation. U. S. Department of Agriculture, Agriculture Handbook. 1965.
[325]Woodruff, N. P.; Siddoway, F. H. A wind erosion equation. Soil Science Society of America Proceedings. 1965, 29(5):602-608.
[326]Woodward, S. J. A simple model for optimizing rotational grazing.Agricultural System.1993, 41:123-155.
[327]Xu-Ri, Yuesi Wang, Xunhua Zheng, Baomin Ji and MingxingWang. A comparison between measured and modeled N_2O emissions from Inner Mongolian semi-add grassland.Plant and Soil.2003, 255: 513-528.
[328]Yue Depeng, Liu Yongbing, Zang Runguo, Wang Xian. Regularities of wind-erosion of different land-use types in Yongding River sandy land, Beijing. Front. For. China.2006, 2:208-213.
[329]Zacheis, A.; Hupp, J.W.; Ruess, R. Effects of migratory geese on plant communities of an Alaskan salt marsh. Journal of Ecology. 2001, 89(1):57-71.
[330]Zacheis, A.; Ruess, R.W.; Huup, J.W. Nitrogen dynamics in an Alaskan salt marsh following spring use by geese. Oecologia. 2002, 130(4): 600-608.
[331]安渊，徐柱，阎志坚．不同退化梯度草地植物和土壤的差异．中国草地．1999，4：31—36．
[332]安渊，陈丽君，孟慧琳．不同践踏强度对沟叶结缕草坪用性状的影响．．草地学报．2005，13(4)：299-303．
[333]安渊，陈丽君，孟慧琳，孙明，杨晓光．封闭时间对模拟践踏的沟叶结缕草草坪质量的影响．草业学报．2006，15(6)：81-86．
[334]敖特根，李勤奋．内蒙古草地风蚀状况与影响其主要自然因素．内蒙古草业．2001，1：31-34．
[335]白可喻，韩建国，王培．放牧强度对新麦草土壤氮素分配及其季节动态的影响．草地学报．1999b，7(4)：308-318．
[336]白可喻，王培，韩建国．放牧强度对新麦草人工草地氮素在牧草与土壤中的分配和动态的影响．草地学报．1999a，7(3)：46-53．
[337]白文明，程维信，李凌浩．微根窗技术及其在植物根系研究中的应用．生态学报．2005，25(11)：3076-3081．
[338]白云飞．降水量的季节分配对羊草草原群落地上部分生物量的影响的数学模型．草业学报．1997，2：15-24．
[339]北京体育学院编．运动生物力学．北京：人民教育出版社．1981．
[340]卜兆宏，刘绍清．土壤流失量及其参数实测的新方法．土壤学报．1995，32(2)：210-219．
[341]常会宁，夏景新．草地放牧制度及评价．国外畜牧学—草原与牧草．1994，4：9-14．
[342]常生华，李广，侯扶江．我国沙尘暴发生日数的空间分布格局．中国沙漠．2006，26(3)：384-388．
[343]陈莉，刘照辉，赵红洋等．运动场草坪践踏强度及其恢复系的研究．草原与草坪．2002，(4)：28-30
[344]陈利顶，傅伯杰．干扰的类型、特征及其生态学意义．生态学报．2000，20(4)：581-586．
[345]陈明．神经网络模型．大连：大连理工大学出版社．1993．
[346]陈明华，周福建，黄炎和．土壤可蚀性因子的研究．水土保持学报．1995，9(1)：19-24．
[347]陈善科，徐平，张学英．阿拉善荒漠生态危机及其治理对策．草原与草坪．2000，(3)：9-11．
[348]陈震，吴俊兰编著．土壤肥料理化性质简易测定法．北京：农业出版社．1980，p63．
[349]陈忠东．放牧干扰对林地及林木生长影响分析与评价．林业科学研究．2003，16(3)：312-318．
[350]陈佐忠，黄德华，张鸿芳．内蒙古锡林河流域羊草草原和大针茅草原地下生物量与降水量关系模型探讨．见：草原生态系统研究(2)．北京：科学出版社．1988．20-26．
[351]程炽民．长芒草草地在封育条件下群落结构和生物量变化的研究．草业科学．1993，10(2)：14-18．
[352]程积民，万惠娥．中国黄土高原植被建设与水土保持．北京：中国林业出版社．2002．
[353]戴其根，周兰胜，陈后庆，张洪程，霍中洋，许柯．践踏强度对不同坪床结构狗牙根地上部生长的影响．扬州大学学报(农业与生命科学版)．2006，27(2)：86-90．
[354]丁飞，张祖兴，蔡阿兴，胡续礼，姜小三，潘剑君．土壤侵蚀强度分级标准中土壤厚度参考指标适用性的探讨．中国农学通报．2006，22(7)：343-346．
[355]董长虹编著．神经网络与应用．北京：国防工业出版社．2005．
[356]董全民，李青云，马玉寿，施建军．耗牛放牧率对小嵩草高寒草甸地上、地下生物量的影响初析．四川草原．2004，2：20-27．
[357]董全民，赵新全，马玉寿，代勇，施建军，王启基．江河源区披碱草和星星草混播草地土壤物理性状对耗牛放牧强度的响应．草业科学．2005，22(6)：65-70．
[358]董全民，赵新全，马玉寿，李芙蓉，来德珍．不同耗牛放牧率下江河源区垂穗披碱草-星星草混播草地第一性生产力及其动态变化．中国草地学报．2006，28(3)：5-15．
[359]董全民，赵新全，马玉寿，李青云，王启基，施建军．耗牛放牧率与小禽草高寒草甸暖季草地地上、地下生物量相关分析．草业科学．2005，22(5)：65-71．
[360]董世魁，江源，黄晓霞．草地放牧适宜度理论及牧场管理策略．资源科学．2002，24(6)：35-41．
[361]董世魁．什么是草原载畜量．国外畜牧学-草原与牧草．1998，(1)：6-11．
[362]杜睿，王庚辰，吕达仁．放牧对草原土壤N_2O产生及微生物的影响．环境科学．2001，22(4)：11-15．
[363]杜玉珍，赵钢，阎景赞．放牧制度对天然草地土壤物理性状及奶牛生产性能的影响．中国土地．2005，27(4)：47-51．
[364]范春梅，廖超英，孙长忠，许喜明，李培玉．放牧对黄上高原丘陵沟壑区林草地土壤特性的影响．西北农业学报．2006，15(1)：24-28．
[365]范锦龙，潘志华，赵举，郑大玮，妥德宝，赵沛义．风蚀强度的空间差异及影响分析．水土保持学报．2003，17(2)：100-136．
[366]冯利华．基于ANN的土壤侵蚀研究．土壤侵蚀与水土保持学报．1999，5(6)：105-109．
[367]冯晓静，高焕文，毛宁，王树东．永定河沙地播草盖沙效果的风洞试验研究．中国水土保持．2006，4：16-17．
[368]符义坤，孙吉雄．草地改良与利用．兰州：甘肃科学技术出版社．1986．57-135．
[369]傅华，王彦荣，吴彩霞，塔拉腾．放牧对阿拉善荒漠草地土壤性状的影响．中国沙漠．2002，22(4)：339-343．
[370]高英志，韩兴国，汪诗平．放牧对草原土壤的影响．生态学报．2004，24(4)：790-797．
[371]关世英，常金宝，贾树海，李绍，良陈有君，王玉芬．草原暗栗钙土退化过程中的土壤性状及其变化规律的研究．中国草地．1997，33：39-43．
[372]郭冬梅，白英，郭炜．表层风蚀土壤粒径分布的分形特征研究．内蒙古农业大学学 报．2005，26(1)：82-86．
[373]郭忠升，邵明安．土壤水分植被承载力数学模型的初步研究．水利学报．2004，10：95-99．
[374]韩国栋．划区轮牧和季节连续放牧绵羊的牧食行为．中国草地．1993．(2)：1-14．
[375]韩永伟，韩建国，张蕴薇，王堃．农牧交错带退耕还草地土壤风蚀影响因子分析．生态环境．2005，14(3)：382-386．
[376]郝高建，赵先贵．甘肃省环县生态环境建设及生态农业发展模式研究．水土保持研究．2004，11(1)：23-26．
[377]郝高建，赵昕，赵先贵．黄土高原生态建设与生态农业发展模式—以甘肃省环县为例．干旱区研究．2004，21(1)：44-48．
[378]郝兴中，常生华．黄土高原农牧交错带草业发展前景浅析—对环县苜蓿草产业发展的分析．草业科学．2002，19(5)：40-42．
[379]贺秀斌，文安邦，张信宝，朱波．农业生态环境评价的土壤侵蚀退耦指标体系．土壤学报．2005，42(5)：852-856．
[380]红梅，韩国栋，赵萌莉，索培芬，潘林瑞．放牧强度对浑善达克沙地土壤物理性质的影响．草业科学．2004，21(12)：108-111．
[381]侯扶江，南志标，肖金玉，常生华．重牧退化草地的植被、土壤及其耦合特征．应用生态学报．2002．13(8)：915-922．
[382]侯扶江，任继周．甘肃马鹿冬季放牧的践踏作用及其对土壤理化性质影响的评价．生态学报．2003，23(3)：486-495．
[383]侯扶江，杨中艺．放牧对草地的作用．生态学报．2006，26(1)：244-264．
[384]侯扶江，常生华，于应文，林慧龙．放牧家畜的践踏作用研究评述．生态学报．2004，24(4)：133-139．
[385]侯扶江，肖金玉，南志标．黄土高原退耕地的生态恢复．应用生态学报．2002，13(8)：923-929．
[386]侯扶江．放牧对牧草光合作用呼吸作用和氮碳吸收与转运的影响．应用生态学报．2001，12(6)：938-933．
[387]胡孟春，王周龙．土壤风蚀的自然-社会复合系统动态过程模拟研究．科学通报．1994，39(12)： 1118-1121．
[388]胡云锋，刘纪远，庄大方，曹红霞，闫慧敏，杨风亭．风蚀土壤剖面~(137)Cs的分布及侵蚀速率的估算．科学通报．2005，50(9)：933-937．
[389]胡云锋，刘纪远，庄大方，杨风亭．土地利用动态与风力侵蚀动态对比研究—以内蒙古自治区为例．地理科学进展．2003，22(6)：541-550．
[390]胡中民，樊江文，钟华平，韩彬．中国草地地下生物量研究进展．生态学杂志．2005，24(9)：1095-1101．
[391]胡自治，孙吉雄，李洋，龙瑞军，杨发林．甘肃天祝主要高山草地的生物且及光能转化率．植物生态学报．1994，18(2)：121-131．
[392]环县生态环境建设领导小组办公室．环县1999年生态环境建设文件汇编．2000，12．
[393]黄富祥，高琼，赵世勇．生态学视角下的草地载畜量概念．草业学报．2000，9(3)：48-57．
[394]黄金杰，李士勇，左兴权．一个基于粗糙集的水土流失防治动态决策系统．中国地质灾害与防治学报．2002，13(3)：67-72．
[395]贾慎修主编．草地学．北京：中国农业出版社．1982．p186-188．
[396]贾树海，王春枝，孙振涛，李绍良，陈有君，靳存旺．放牧强度和时期对内蒙古草原土壤压实效应研究．草地学报．1999，7(3)：217-222．
[397]贾树海，崔学明，李绍良．牧压梯度上土壤物化性质的变化．见：中国科学院内蒙古草原生态系统定位研究站编．草原生态系统研究(第五集)．北京：科学出版社．1996．p12-16．
[398]贾树海，张海涛，李晓安，钱凤魁，王秋兵．放牧强度对草原砂质栗钙土某些物理性质影响的研究．土壤通报．2006，37(4)：821-823．
[399]贾媛媛，郑粉莉，杨勤科．国外水蚀预报模型述评．水士保持通报．2003，3(5)：82-87．
[400]江忠善，郑粉莉，武敏．中国坡面水蚀预报模型研究．泥沙研究．2005，4：1-6．
[401]姜娜，邵明安，雷廷武．水蚀风蚀交错带坡面土壤入渗特性的空间变异及其分形特征．土壤学报．2005，42(6)：904-908．
[402]蒋文兰，张英俊，符义坤，冉繁军．绵羊宿营法防除天然草地灌木杂草研究，Ⅱ绵羊啃食和践踏对植物与土壤物理性状的影响．草业学报．1999，8(增刊)：82-89．
[403]蒋文兰，瓦庆荣，刘兴元．贵州岩溶山区绵羊宿营法改良天然草地综合研究．1．绵羊宿营时间、强度及牧草混播组合的处理效果．草业学报．1996a，5(1)：17-25．
[404]蒋文兰，瓦庆荣，吴明强．贵州岩溶山区绵羊宿营法改良天然草地综合研究．3．改良草地的技术、生态、经济效果研究．草业学报．1996c，5(1)：31-36．
[405]蒋文兰，瓦庆荣，张明忠．贵州岩溶山区绵羊宿营法改良天然草地综合研究．2．改良后草地牧草生产力持久性研究．草业学报．1996b，5(1)：26-30．
[406]敬永方，常生华．环县天然草原退化现状与治理对策．草业科学．2002，19(3)：9-11．
[407]敬永方，张富忠，常生华．黄土高原农牧交错带苜蓿草地固沙效果观察—环县试验报告．草业科学．2003，20(7)：58-59．
[408]瞿王龙，裴世芳，周志刚，张宝林，傅华．放牧与围封对阿拉善荒漠草地土壤有机碳和植被特征的影响．甘肃林业科技．2004，29(2)：4-6．
[409]雷阿林，史衍玺，唐克丽．土壤侵蚀模型实验中的土壤相似性问题．科学通报．1996，41(19)：1801-1804．
[410]李博，雍世鹏，李瑶．中国的草原．北京：科学出版社．1990．
[411]李博．生态学与草地管理．中国草地．1994，1：1-8．
[412]李博．中国北方草地退化及其防治对策．中国农业科学．1997，30(6)：1-9．
[413]李德颖，Warren，F．H．混播草坪上足球运动践踏模拟效果的研究．农业工程学报．1997，(2)：164-168．
[414]李冬杰，杨培岭，王勇，刘洪禄，郝仲勇．土壤水分对草坪草蒸散及生长特性的影响．草地学报．2005，13(3)：308-312．
[415]李建龙，许鹏，孟林，王建华．不同轮牧强度对天山北坡低山带蒿属荒漠秋场土草畜影响研究．草业学报．1993，2(2)：60-65．
[416]李鹏，李占斌，鲁克新．黄土区草木植被根系与土壤垂直侵蚀产沙关系研究．植物生态学报．2006，30(2)：302-306．
[417]李绍良，陈有君，关世英，康师安．土壤退化与草地退化关系的研究．干旱区资源与环境．2002，16(1)：92-95．
[418]李绍良，陈有君．锡林河流域栗钙土及其物理性状与水分动态的研究．中国草地．1999，3：71-76．
[419]李绍良，贾树海，陈有君，康师安，关世英，何婕平．内蒙古草原土壤退化进程及其评价指标的研究．土壤通报．1997，28(6)：241-243．
[420]李胜功，赵哈林，何宗颖，常学礼，原圆芳信，大黑俊哉，根本正之．不同放牧压力下草地微气象的变化与草地荒漠化的发生．生态学报．1999，19(5)：697-704．
[421]李师翁，范小峰．甘肃环县天然草地植被近40年演变的研究．水土保持学报．2003，17(6)：114-117．
[422]李树会，张东为．美国有关放牧对土壤性质影响的研究．水土保持科技情报．2003，17(1)：8-9．
[423]李文建，韩国栋．放牧家畜研究进展．内蒙古畜牧科学．2000，21(3)：24-27．
[424]李香真，陈佐忠．不同放牧率对草原植物与土壤C、N、P含量的影响．草地学报．1998，6(2)：90-98．
[425]李香真，曲秋皓．内蒙高原草原土壤微生物量碳氮特征．土壤学报．2002，39(1)：97-104．
[426]李香真．放牧对暗栗钙土磷的贮量和形态的影响．草业学报．2001，10(2)：28-32．
[427]李晓丽，申向东．结皮土壤的抗风蚀性分析．干旱区资源与环境．2006，20(2)：203-207．
[428]李银鹏，季劲钧．全球陆地生态系统与大气之间碳交换的模拟研究．地理学报．2001，56(4)：379-389．
[429]李银鹏，季劲钧．内蒙古草地生产力资源和载畜量的区域尺度模式评估．自然资源学报，2004，19(4)：610-616．
[430]李英年．高寒草甸牧草产量和草场载畜量模拟研究及对气候变暖的响应．草业学报．2000，9(2)：77-82．
[431]李英年．高寒草甸植物地下生物量与气象条件的关系及周转值分析．中国农业气象．1998，19(1)：36-39．
[432]李永宏，莫文红，杨持．内蒙古主要草原植物群落地上生物量和理论载畜量及其与气候的关系．干旱区资源与环境．1994，8(4)：43-50．
[433]过度放牧对生态环境的影响与控制对策．中国沙漠．2005，25(3)：404-408．
[434]李忠辉，郑大玮，潘志华．农牧交错带缓坡丘陵区土壤风蚀研究—以内蒙古后山地区为例．中国水土保持．2004,6：17-20．
[435]李子忠，黄顶，王忠彦．灌溉制度对老芒麦(Elymus sibiricus)生长的影响．中国农业科学．2005，38(8)：1621-1628．
[436]廖超英，李靖，郑粉莉，刘国彬．国外土壤风蚀预报的研究历史与动向．水土保持研究．2004，11(4)：50-53．
[437]林慧龙，董世魁．高寒地区多年生禾草混播草地种间竞争效应分析．草业学报．2003，12(3)：79-82．
[438]林慧龙，侯扶江．草地农业生态系统中的系统耦合与系统相悖研究动态．生态学报．2004，24(6)：1252-1258．
[439]林慧龙．草地农业：从结构性描述到精确化发展刍议．草业科学．2007，24(6)：9-17．
[440]刘艾，刘德福．我国草地生物量研究概述．内蒙古草业．2005，17(1)：7-11．
[441]刘宝元，张科利，焦菊英．土壤可蚀性及其在侵蚀预报中的应用．自然资源学报．1999，14(4)：345-350．
[442]刘秉正，吴发启．土壤侵蚀．西安：陕西人民出版社．1997．
[443]刘吉峰，李世杰，秦宁生，于守兵．青海湖流域土壤可蚀性K值研究．干旱区地理．2006，29(3)：321-326．
[444]刘建军，浦野忠朗，鞠子茂，及川武久．放牧对草原生态系统地下生产力及生物量的影响．西北植物学报．2005，25(1)：88-93．
[445]刘良梧，周建民，刘多森，等．农牧交错带不同利用方式下草原土壤的变化．土壤．1998，30(5)：225-229．
[446]刘晓民，程国彦，郝建国，范希全．农田留茬覆盖抗风蚀效果浅析．农村牧区机械化．2005,62(1)：10—13．
[447]刘艳萍，荣浩，邢恩德．草原水保生态环境监测整体发展研究．水土保持科技情报．2004，5：40-42．
[448]柳承茂．MATLAB 5.X入门与应用．北京：科学出版社．1999．
[449]龙利群，李新荣．微生物结皮对两种一年生植物种子萌发和出苗的影响．中国沙漠．2002，22(6)：581-585．
[450]鲁如坤．土壤农业化学分析方法．北京：中国农业科技出版社．1999．p：638．
[451]罗俊强，韩烈保，陈宝书．草坪地下生物量与坪用性状的关系．北京林业大学学报．2000，22(2)：77-80．
[452]马春梅，杨静，卫智军．放牧绵羊牧食习性的比较研究．内蒙古草业．2000，(2)：53-57．
[453]马东涛，祁龙，邓晓峰．甘肃环县东山黄土泥流综合治理．山地学报．2000，18(3)：217-220．
[454]马生发，胡景平．环县北部沙漠化现状及防治对策．甘肃农业科技．2002，5：8-9．
[455]马文红，韩梅，林鑫，任艳林，王志恒，方精云．内蒙古温带草地植被的碳储量．干旱区资源与环 境．2006，20(3)：192-195．
[456]马永年．环县农业生态环境建设中存在的问题及对策．甘肃农业科技．2004，2：3-5．
[457]迈克·费斯特．土壤生物结皮在干旱半干旱地区退化生态系统恢复中的作用．中国水土保持科学．2005，3(4)：42-47．
[458]毛留喜，孙艳玲，延晓冬．陆地生态系统碳循环模型研究概述．应用生态学报．2006，17(11)：2189-2195．
[459]门明新，赵同科，彭正萍，宇振荣．基于土壤粒径分布模型的河北省土壤可蚀性研究．中国农业科学．2004，37(11)：1647-1653．
[460]孟祥亮，严平，宋阳，杨秀春，吴晓．风蚀容忍量研究进展及其若干问题的探讨．中国沙漠．2005，25(3)：315-319．
[461]内蒙古农牧学院．草原管理学．北京：中国农业出版社．1981，p63．
[462]内蒙古农牧学院主编．畜牧学．北京：农业出版社，1981年，p59，162，
[463]倪九派，谢春燕，魏朝富，谢德体．土壤侵蚀预测建模研究进展．中国水土保持科学．2005，3(2)：66-71．
[464]潘锋．我国土壤家底有多“厚”? 《科学时报》2005．6．27．
[465]裴海昆．不同放牧强度下土壤有机质特性变化的研究．青海畜牧兽医杂志．2004b，34(4)：1-3．
[466]裴海昆．不同放牧强度对土壤养分及质地的影响．青海大学学报(自然科学版)2004a，22(4)：29-31．
[467]彭坷珊．中国土壤侵蚀影响因素及其危害分析．首都师范大学学报(自然科学版)．2000，21(2)：88-94．
[468]彭棋，王宁．不同放牧制度对草地植被的影响．农业科学研究．2005，26(1)：27-30．
[469]蒲小鹏，徐长林，刘晓静．放牧利用对金露梅灌丛土壤理化性质的影响．甘肃农业大学学报．2004，39(1)：39-41．
[470]朴世龙，方精云，贺金生，肖玉．中国草地植被生物量及其空间分布格局．植物生态学报．2004，25(4)：491-498．
[471]齐矗华，甘枝茂．黄土高原侵蚀地貌与水土流失关系研究．西安：陕西教育出版社．1991．p12-89．
[472]钱正安，蔡英，刘景涛等．中国北方沙尘暴研究的若干进展．干旱区资源与环境．2004，18(1)：1-8．
[473]任继周，胡自治，张自和，侯扶江，陈全功．中国草业生态经济区初探．草业学报．1999，8(专辑)：12-22．
[474]任继周，郭博，李逸民，李琪，雍际炳．高山草原生产性能的初步探讨．甘肃农业大学科学研究论文汇编．1959，4：：37-48．
[475]任继周，胡自治，牟新待，张普金．草原的综合顺序分类及其草原发生的意义．中国草地．1980，(1)：12-24．
[476]任继周，金巨和．牦牛群放牧习性的观察研究．中国畜牧兽医杂志．1956(2)：58-62．
[477]任继周，李逸民，郭博，李琪．藏羊群自由放牧与分区轮牧的观察研究．中国畜牧兽医杂志．1954(4)：143-157．
[478]任继周，王钦．甘肃天祝永丰滩高山草原更新措施的研究简报．甘肃农业大学学报．1959，4：11-20．
[479]任继周．草地农业生态学．北京：中国农业出版社．1995．p51-84．
[480]任继周．草原地下生物量的启示．草业科学．2006，23(6)：91．
[481]任继周．天祝高山草原早春灌溉问题的探讨(1959)．《任继周文集》第二卷．北京：中国农业出版社，2005．
[482]任继周编著．关于高山草原的调查研究．南京：畜牧兽医图书出版社出版．1957年7月．
[483]任继周编著．草原的培育和利用．兰州：甘肃人民出版社出版．1962年7月．
[484]任继周主编．草地农业生态系统通论．合肥：安徽教育出版社．2004
[485]任继周主编．草业科学研究方法．北京：中国农业出版社．1989．p4．
[486]任继周主编．草原调查与规划．北京：农业出版社．1985．p110-116．
[487]任继周主编．草原学(高等农业学校教学参考书)．北京：农业出版社．1959．
[488]任继周主编．草地农业生态系统通论．合肥：安徽教育出版社．2004．
[489]戎郁萍，韩建国，王培，毛培胜．放牧强度对草地土壤理化性质的影响．中国草地．2001，23(4)：41-46．
[490]尚占环，姚爱兴．国内放牧管理措施的综述．宁夏农林科技．2004，2：32-35．
[491]邵月红，潘剑君，许信旺，米高奇．浅谈土壤有机碳密度及储量的估算方法．土壤通报．2006，37(5)：1007-1011．
[492]宋炳煜．几个主要地面因子对草原群落蒸发蒸腾的影响．植物生态学报．1996，20(6)：485-493．
[493]宋桂龙，韩烈保，周陆波．电动蛙式草坪践踏器．农业机械学报．2006，37(5)：168-170．
[494]宋桂龙，徐泽荣．运动场草坪耐践踏性研究进展．四川草原，2004，(8)：6-9．
[495]宋阳，刘连友，严平，曹彤．土壤可蚀性研究述评．干旱区地理．2006，29(1)：124-131．
[496]宋颖．土壤侵蚀模型研究进展及发展方向．山西水利科技．2006，161(3)：39-41．
[497]苏永中，赵哈林，张铜会，崔建恒．不同强度放牧后自然恢复的沙质草地土壤性状特征．中国沙漠．2002，22(4)：333-338．
[498]孙吉雄．草坪学．北京：中国农业出版社．1996．p1-17．
[499]孙力安，梁一民．草地地下生物量研究综述．国外畜牧学：草原与牧草．1993，1：6-14．
[500]孙力安，刘国彬，梁一民．不同直径土钻测定草地地下生物量方法探讨．中国草地．1994，2：32-35．
[501]滕星，王德利，张宝田．羊草(Leymus chinensis)草地雨天放牧与非雨天放牧的绵羊采食特征．生态学报．2006，26(3)：762-767．
[502]田志珍，常生华，肖金玉，侯扶江，南志标．滩羊体重对放牧强度的短期效应．家畜生态．2004，25(2)：26-31．
[503]汪诗平．放牧绵羊行为生态学研究，Ⅱ不同放牧率对放牧绵羊牧食行为的影响．草业学报．1997，6(1)：10-17．
[504]王长庭，王启基，沈振西，彭红春，李海英．模拟降水对高寒草甸群落影响的初步研究．草业学报．2003，12(2)：25-29．
[505]王尔大，Wyatte Harman，郑大玮，常欣，程序．旱作农区轮作和留茬处理方式对风蚀的影响—应用EPIC模型进行模拟和分析的武川案例．中国农业科学．2002，35(11)：1330-1336．
[506]王关禄，张治国等编著．土壤知识与土壤普查技术．北京：水利电力出版社．1983．p：1-42，295-310．
[507]王国杰，汪诗平，郝彦宾，蔡学彩．水分梯度上放牧对内蒙古主要草原群落功能群多样性与生产力关系的影响．生态学报．2005，25(7)：1649-1656．
[508]王礼先，周金星．关于荒漠化、沙漠化、风沙化和沙化的概念．科技术语研究．2000，4(2)：31．
[509]王利兵，胡小龙，余伟在，李钢铁，郭建英．沙粒粒径组成的空间异质性及其与灌丛大小和上壤风蚀相关性分析．干旱区地理．2006，29(5)：687-693．
[510]王明玖，马长升．两种方法估算草地载畜量的研究．中国草地．1994，(5)：19-22．
[511]王仁忠．放牧干扰对松嫩平原羊草草地的影响．东北师大学报(自然科学版)．1996，(4)：77-82．
[512]王绍强，周成虎．中国陆地土壤有机碳库的估算．地理研究．1999，18(4)：349-356．
[513]王淑强，胡直友，李兆方．不同放牧强度对红三叶、黑麦草草地植被和土壤养分的影响．自然资源学报．1996，11(3)：280-287．
[514]王思远，王光谦，陈志祥．黄河流域土地利用与土壤侵蚀的耦合关系．自然灾害学报．2005，14(1)：32-37．
[515]王涛，吴薇，赵哈林，董治宝，薛娴．沙漠化过程中生物量损失的初步评估．中国沙漠．2005，25(4)：453-456．
[516]王万忠，焦菊英．中国的土壤侵蚀因子定量评价研究．水土保持通报．1996，16(5)：1-20．
[517]王小丹，钟祥浩，范建容．西藏水土流失敏感性评价及其空间分异规律．地理学报．2004，59(2)：183-188．
[518]王效科，欧阳志云，肖寒，苗鸿，傅伯杰．中国水土流失敏感性分布规律及其区划研究．生态学报．2001，21(1)：14-19．
[519]王雪芹，张元明，张伟民，韩致文．古尔班通古特沙漠生物结皮对地表风蚀作用影响的风洞实验．冰川冻土．2004，26(5)：632-638．
[520]王艳芬，陈佐忠，Larry，T．Tieszen．人类活动对锡林郭勒地区主要草原土壤有机碳分布的影响．植物生态学报．1998，22(6)：545-551．
[521]王艳芬，汪诗平．不同放牧率对内蒙古典型草原地下生物量的影响．草地学报．1999，7(3)：198-205．
[522]王跃思，胡玉琼，纪宝明等．放牧对内蒙古草原温室气体排放的影响．中国环境科学．2002，22(6)：490-494．
[523]王跃思，纪宝明，黄耀等．农垦与放牧对内蒙古草原N_2O、CO_2排放和CH_4吸收的影响．环境科学，2001，22(6)：7-13．
[524]王占礼，黄新会，牛振华．国内主要流域侵蚀产沙模型评述．水土保持研究．2004，11(4)：28-33．
[525]王兆印，王光谦，李昌志，王费新．植被—侵蚀动力学的初步探索和应用．中国科学(D辑)．2003，33(10)：1013-1023
[526]魏翔，李占斌．土壤侵蚀对生态系统的影响．水土保持研究．2006，13(1)：245-264．
[527]吴发启，赵晓光，刘秉正，贾锐鱼．地表糙度的量测方法及对坡面径流和侵蚀的影响．西北林学院学报．1998，13(2)：15-19．
[528]吴楠，梁少民，王红玲．动物践踏干扰对生物结皮中微生物生态分布的影响．干旱区研究．2006，23(1)：50-55．
[529]夏景新．载畜率调控的理论与牧场管理实践．中国草地．1995，1：46-54．
[530]徐宪立，马克明，傅伯杰，刘宪春，黄勇，祁建．植被与水土流失关系研究进展．生态学报．2006，26(9)：3137-3143．
[531]许鹏主编．草地资源调查规划学．北京：中国农业出版社．2000，p67-75．
[532]许志信，白飞，曲永全．草原植被利用强度对水土流失影响的研究．内蒙古草业．2000，2：1-7．
[533]许志信，王俊国，赵明旭．干草原植被利用强度对水土流失影响的研究．内蒙古草业．2001a，2：1-6．
[534]许志信，张晓明，白飞，昭和斯图．草甸草原植被利用强度对水土流失影响的研究．内蒙古农业大学学报．2001b，22(-)：68-73．
[535]许志信，赵萌莉．过度放牧对草原土壤侵蚀的影响．中国草地．2001，23(6)：59-63．
[536]许志信，赵萌莉．草原植被与水土流失．内蒙古草业．2000，1：1-6．
[537]许志信．控制载畜量是维持草地生态平衡的关键．草业科学．1990，7(5)：1-10．
[538]许中旗，李文华，阂庆文，敖其尔，王英舜，韩喜，何旭生，贺俊杰．典型草原抗风蚀能力的实验研究．环境科学．2005，26(5)：164-168．
[539]鄢燕，张建国，张锦华，范建容，李辉霞．西藏那曲地区高寒草地地下生物量．生态学报．2005，25(11)：2818-2813．
[540]杨理，侯向阳．以草定畜的若干理论问题研究．中国农学通报．2005，21(3)：346-349．
[541]杨培岭，罗远培，石元春．用粒径的重量分布表征的土壤分形特征．科学通报．1993，38(20)：1896-1899．
[542]杨萍，胡续礼，姜小三，何旭东，潘剑君．小流域尺度土壤可蚀性(K值)的变异及不同采样密度对其估值精度的影响．水土保持通报．2006，26(6)：35-39．
[543]杨文治．黄土高原土壤水分研究．北京：科学出版社．2000．
[544]杨小红，董云社，齐玉春等．草地生态系统土壤氮转化过程研究进展．中国草地．2004，26(2)：54-62．
[545]杨秀春，严平，刘连友．土壤风蚀研究进展与评述．干旱地区农业研究．2003，21(4)：147-153．
[546]杨智明，王琴，王秀娟．放牧强度对草地牧草物候期生活力和土壤含水量的影响．农业科学研究．2005，26(3)：1-3．
[547]杨智明，杨刚，纪庆文，王海军．干筛法和水洗法在测定地下生物量中的对比分析．宁夏农学院学报．2004，25(2)：99-100．
[548]姚爱兴，王培，夏景新，樊奋成．不同放牧强度下奶牛对多年生黑麦草／白三叶草地土壤特性的影响．草地学报．1995，3(3)：181-189．
[549]叶其孝．大学生数学建模竞赛辅导教材．长沙：湖南教育出版社．1993．p49-69．
[550]移小勇，赵哈林，张铜会，李玉强，刘新平，卓鸿．挟沙风对土壤风蚀的影响研究．水土保持学报．2005，19(3)：58-61．
[551]俞斌华，侯扶江，林慧龙．牧草种群生长对家畜践踏的短期响应．草业学报．2005，14(4)：119-124．
[552]宇万太，于永强．植物地下生物量研究进展．应用生态学报．2001，12(6)：927-932．
[553]玉辉，何兴元，周广胜．放牧强度对羊草草原的影响．草地学报．2002，10(1)：45-49．
[554]袁建平．土壤侵蚀强度分级标准适用性初探．水土保持通报．1999，19(6)：54-57．
[555]袁庆华，蒋文兰．羊群宿营对蛴螬控制及草地恢复的影响．中国草地．1995，2：15-19．
[556]袁庆华．高强度放牧对草地蛴螬种群数量的影响．草业学报．1995，4(1)：30-35．
[557]张春来，邹学勇，董光荣，刘玉璋．植被对土壤风蚀影响的风洞实验研究．水土保持学报．2003，17(3)：31-33．
[558]张德二．我国历史时期以来降尘的天气气候学初步分析．中国科学．1984，24(3)：278-288．
[559]张东秋，石培礼，张宪洲．土壤呼吸主要影响因素的研究进展．地球科学进展，2005，20(7)：778-785．
[560]张华，李锋瑞，伏乾科，吕子君．沙质草地植被防风抗蚀生态效应的野外观测研究．环境科学．2004，25(2)：119-124．
[561]张科利，蔡永明．土壤可蚀性动态变化规律研究．地理学报．2001，56(6)：673-681．
[562]张娜，梁一民．黄土丘陵区两类天然草地群落地下部生长及其与土壤水分关系的比较研究．西北植物学报．1999，19(4)：699-706．
[563]张铜会，赵哈林，常学礼，白户康人，大黑俊哉．灌水对沙地草场几种植物生长的影响．中国沙漠．1999，19(增刊)：23-25．
[564]张铜会，赵哈林，大黑俊哉．沙质草地连续放牧后某些上壤性质的变化．中国草地．2003，25(1)：9-12．
[565]张伟华，关世英，李跃进．不同牧压强度对草原土壤水分、养分及其地上生物量的影响．干旱区资源与环境．2000，14(4)：61-64．
[567]张学雷，龚子同．人为诱导下中国的土壤退化问題．生态环境．2003，12(3)：317-321．
[568]张岩，袁建平，刘宝元．土壤侵蚀预报模型中的植被覆盖与管理因子研究进展．应用生态学报．2002，13(8)：1033-1036．
[569]张燕，张洪，彭补拙，杨浩．不同土地利用方式下农地土壤侵蚀与养分流失．水土保持通报．2003，23(1)：23-31．
[570]张英杰，宋豫秦．论我国半干旱草原地区沙漠化防治战略的转型．中国沙漠．2004，24(1)：87-91．
[571]张英俊，蒋文兰，符义坤，樊晓东．绵羊宿营法防除天然草地灌木杂草研究，Ⅰ回顾与进展．草业学报．1999，8(专辑)：76-81．
[572]张英俊．绵羊宿营法清除天然草地灌木无毛丑柳的效果和机理研究．甘肃农业大学博士论文．1999．
[573]张英俊．绵羊宿营法清除天然植被对土壤和植物的影响．草地学报．2002，10(4)：251-257．
[574]张玉斌，郑粉莉，贾媛媛．WEPP模型概述．水土保持研究．2004，11(4)：146-149．
[575]张蕴薇，韩建国，李志强．放牧强度对土壤物理性质的影响．草地学报．2002，10(1)：74-78．
[576]张蕴薇，韩建国，杨富裕．华北农牧交错带地区放牧强度对草地土壤氮营养的影响．四川草原．2005，1：7-9．
[577]张治国，曲继宗，卫元太，崔峰．土壤侵蚀模数控制率计算方法探讨．山西水土保持科技．2004，1：21-22．
[578]张自和．草原退化的后果及深层原因探讨．草业科学．1995，12(6)：1-5．
[579]赵刚，许志信，李德新．反刍家畜牧食行为综述．内蒙古农业大学学报．2000，21(2)：109-116．
[580]赵哈林，根本正之，大黑俊哉，李胜功．内蒙古科尔沁沙地放牧草地的沙漠化机理研究．中国草地．1997，3：15-23．
[581]赵焕勋，王学东．内蒙古土壤侵蚀灾害研究．干旱区资源与环境．1994，8(4)：35-42．
[582]赵吉．不同放牧率对冷蒿小禾草草原土壤微生物数量和生物量的影响．草地学报．1999，7(3)：223-227．
[583]赵立祥．草原荒漠化的物理过程．草业科学．2004，21(11)：7-10．
[584]赵仁镕，余松烈编著．田间试验方法．北京：农业出版社．1984．
[585]赵西宁，吴普特，冯浩，王万忠，吴发启．坡面土壤侵蚀产沙的神经网络模拟．土壤学报．2006，43(2)：324-327．
[586]赵友．风蚀坑对草原的破坏及治理．当代畜牧．1999，5：41．
[587]郑粉莉，杨勤科，王占礼．水蚀预报模型研究．水土保持研究．2004，11(4)：13-24．
[588]郑淑华，赵萌莉，韩国栋，红梅，贵满全，乌力吉．不同放牧压力下典型草原土壤物理性质与植被关系的研究．干旱区资源与环境．2005，19(7)：199-203．
[589]中国科学院南京土壤研究所．土壤理化分析．上海：上海科学技术出版社．1983．p：593．
[590]中国土壤学会编．土壤农业化学分析方法．北京：中国农业出版社．2000，p146-195、272-276．
[591]中华人民共和国农业部畜牧兽医司，中国农业科学院草原研究所，中国科学院自然资源综合考察委员会编．中国草地资源数据．北京：中国农业科技出版社．1994．
[592]周保鑫，孙吉雄．草坪践踏器的原理及其研制．甘肃农业大学学报．1994，29(1)：93-95．
[593]周道玮，钟秀丽．干扰生态理论的基本概念和扰动生态学理论框架，东北师大学报．1996，1：90-96
[594]周广胜，王玉辉，蒋延玲，杨利民．陆地生态系统类型转变与碳循环．植物生态学报．2002，26(2)：250-254．
[595]周禾，牛建忠．我国草坪科学研究与发展．中国农学通报．2001．17(5)：41-43．
[596]周继成，周青山，韩飘扬．人工神经网络—第六代计算机的实现．北京：科学普及出版社．1993．P47-51．
[597]朱连奇，许叔明，陈沛云．山区土地利用／覆被变化对土壤侵蚀的影响．地理研究．2003，22(4)：432-438．
[598]朱显漠．径河流域土壤侵蚀现象及其演变．土壤学报．1954，2(4)：209-222．
[599]朱震达，陈广庭著．中国土地沙质荒漠化．北京：科学出版社．1994．
[600]朱震达，刘恕．中国北方地区的沙漠化过程及其治理区划．北京：中国林业出版社．1981．p19-22．
[601]朱震达．全球变化和荒漠化-地学前缘．北京：中国科学技术出版社．1997．p213-219．
[2]Adams J. M., Faure H., Faure-Denard L., McGlade J. M., Woodward F. I. Increases in terrestrial carbon storage from the Last Glacial Maximum to the present. Nature.1990, 348:711-714.
[3]Amy Zacheis; Roger W.; Ruess ,Jerry ;W. Hupp. Nitrogen dynamics in an Alaskan salt marsh following spring use by geese. Oecologia.2002, 130:600-608.
[4]Andersen, U. V. Resistance of Danish coastal vegetation types to human trampling. Biological Conservation.1995, 71:223-230.
[5]Anderson, D. C, Harper, K. T. & Rushforth, S. R. Recovery of cryptogamic crusts from grazing on Utah winter ranges. J. Range Manag.1982,35:355-359.
[6]Andr's-abell'n, M; Francisco,R. and Antonio,D. Asseeement of trampling simulation impacts on native vegetation in Mediterranean sclerophyllous forest. Environmental Monitoring and Assessment.2006, 120:93-107.
[7]Augustine, D.J., Frank, D.A. Effects of migratory grazers on spatial heterogeneity of soil nitrogen properties in a grassland ecosystem. Ecology. 2001, 82:3149-3162.
[8]Azenegashe, O. A.; Allen, V. and Fontenot, J. Grazing sheep and cattle together or separately: effect on soil and plants. Agron. J. 1997, 89:380-386.
[9]Bakken,L.R.; Borresen,T.; Njos,A. Effect of soil compaction by tractor traffic on soil structure, denitrification, and yield of wheat. Journal of Soil Science. 1987, 38(3):541-552.
[10]Bardgett, R. D.; Leemans, D. K. The short-term effects of cessation of fertilizer applications, limiting and grazing on microbial biomass and activity in a reseeded upland grassland soil. Biology and Fertility of Soils.1995, 19:148-154.
[11]Barrie Low A, Rebelo AG Vegetation of South Africa, Lesotho and Swaziland. Pretoria: Department of Environmental Affairs & Torism.1998.
[12]Bates, A. J.; Sadler, J.P.; Fowles, A. P. Livestock trampling reduces the conservation value of beetle communities on high quality exposed riverine sediments. Biodivers Conserv.2006,DOI 10.1007/s10531-006-9028-7.
[13]Bates, G. H. The vegetation of footpaths, sidewalks, cart-tracks and gateways. Journal of Ecology. 1935. 23:470-487.
[14]Bates, G.H. A device for the observation of root growth in the soil. Nature.1937, 139:966-967.
[15]Batjes, N. H. The total C and N in soils of the world. European J Soil Society.1996,47:51-63.
[16]Bauer,A.; Cole, C. V; Black, A. L.Soil Property comparisons in virgin grasslands between grazed and non-grazed management systems. Soil Science Society of America Journalist. 1987,51:176-182.
[17]Bayfield, N. Recovery of four montane heath communities on Cairngorm, Scotland from disturbance by trampling. Biological Conservation.1979, 15:165-181.
[18]Bell,K.L. and Bliss,L.C.Alpine disturbance studies:Olympic National Park,USA. Biological Conservation. 1973, 5:25-32.
[19]Belovsky, G F. Optimal foraging and community structure implications for a guild of generalist grassland herbivore. Oecologia. 1981,70:35-52.
[20]Betteridge, K.; Mackay, A. D.; Stepberd, T. G. et al. Effect of cattle and sheep treading on surface configuration of a sedimentary hill soil. Anstralian Journal of Soil Research.1999, 37(4):743-760.
[21]Birch, C.P.D.; Vuichard, N. and Werkman, B.R. Modelling the effects of patch size on vegetation dynamics: bracken (Pteridium aquilinum (L.) Kuhn) under grazing. Annals of Botany.2000, 85 (Supplement B): 63-76.
[22]Blumenthal, M.J.; Ison, T.L. Plant population dynamics in subterranean clover and murex medic swards, 3. effects of pod burial, summer grazing and autumn cultivation on emergence. Australian Journal of Experimental Agriculture.1996, 36(5):533-538.
[23]Boelhouwers, J.; Scheepers, T. The role of antelope trampling on scarp erosion in a hyper-arid environment, Skeleton Coast, Namibia. Journal of Arid Environments.2004, 58:545-557.
[24]Bohn C.C. and Buckhouse J.C. Some responses of riparian soils to grazing anagement in northeastern Oregon. Journal of Range Management. 1985, 38:378-381.
[25]Breland, T. A.; Hansen, S. Nitrogen mineralization and microbial biomass as affected by soil compaction. Soil Biol.Biochem. 1996,28:655-663.
[26]Brown, R. W. The water relations of range plants: Adaptations to water deficits. Pages 291-413 in D.J. Bedunah and R. Sosebee (eds.), Wildland plants: hysiological ecology and developmental morphology. Society for Range Management, Denver, Colorado. 1995.
[27]Bullock, J.M.; Hilt, B.C.; Dale M.P. and Silvertown, J. An experimental study of the effects of sheep grazing on vegetation change in species-poor grassland and the role of seedling recruitment into gaps. J. Appl. Ecol. 1994, 31:493-507.
[28]Burgess, C.P.; Chapman, R.; Singleton, P.L.; Thorn, E.R. Shallow mechanical loosening of a soil under dairy cattle grazing: effects on soil and pasture. New Zealand Journal of Agricultural Research. 2000, 43(2):278-290.
[29]Burke, I. C.; Laurenroth, W. K.; Milchunas, D. G. Biogeochemistry of managed grasslands in central North America. In: Pau, I. E .A. eds. Soil Organic Matter in Temperate Ag roecosystems: Long-term Experiments in North America. Boca Raton: CRC Press. 1997. p85-102.
[30]Butler, D.R. Zoogemorphology. Cambridge University Press, Cambridge. 1995. p231.
[31]Byington, E.K. Grazing land management and water quality. Harpers Ferry (WV): American Society of Agronomy and Crop Science Society of America. 1986.
[32]Cao, G.M.; Tang, Y.H.; Mo, W.H. Grazing intensity alters soil respiration in an alpine meadow on the Tibetan plateau. Soil Biology and Biochemistry.2004, 36:237-243.
[33]Chanasky, D. S. Grazing impacts on bulk density and soil strength in the foothills fescue grasslands of Alberta Canada. Canadian J. of soil science.1995, 75(4):551-557.
[34]Chepil, W. S. Properties of soil which influence wind erosion: 1. The governing principle of surface roughness. Soil Sci. 1950,69:149-162.
[35]Cingolani, A. M.; Cabido, M. R.; Renison, D.; Solis, V. N.Combined effects of environment and grazing on vegetation structure in Argentine granite grasslands. J. Veg. Sci.2003, 14:223-232.
[36]Coffin, D. P.; Laycock, W. A.; Lauenroth, W. K. Disturbance intensity and above- and below-ground herbivory effects on long-tern (1 4 years) recovery of a semiarid grassland. Plant Ecol. 1998, 139:221 -233.
[37]Cole, D. N. and Trull, S. J. Quantifying vegetation response to recreational disturbance in the North Cascades, Washington. Northwest Science.1992,66:229-236.
[38]Cole, D. N. Effects of three seasons of experimental trampling on five montane forest communities and a grassland in Western Montana, USA, Biol. Conserv.1987,40:219-244.
[39]Cole, D. N., and N. Bayfield. Recreational trampling of vegetation: Standard experimental procedures. Biological Conservation. 1993,63:209-215.
[40]Cole, D.N. and Landres, P.B. In Knight, R.L., Gutzwiller, K.J. (eds.) Wildlife and Recreationists - Coexistence through Management and Research, pp.183-202. DC: Island Press. Washington, USA, 1995.
[41]Cole, D.N. and Monz,C.A. Impacts of camping on vegetation: response and recovery following acute and chronic disturbance. Environmental Management. 2003,32(6):693-705.
[42]Cole, D.N. and Spildie, D. R. Hiker, horse and llama trampling effects on native vegetation in Montana, USA. Journal of Environmental Management. 1998, 53:61-71.
[43]Cole, D.N. Disturbance of natural vegetation by camping: experimental applications of low-level stress. Environmental Management. 1995d, 19:405-416.
[44]Cole, D.N. Experimental trampling of vegetation, I. relationship between trampling intensity and vegetation response. Journal of Applied Ecology. 1995a, 32:203-214.
[45]Cole, D.N. Experimental trampling of vegetation, II. Predictors of resistance and resilience. Journal of Apply Ecology.1995b, 32:215-224.
[46]Cole,D.N. Recreational Trampling Experiments: Effects of Trampler Weight and Shoe Type. USDA Forest Service, Research Note INT-RN-425. 1995c.
[47]Colin, P.D. B. The influence of position on genet growth: a simulation of a population of bracken (Pteridium aquilinum (L.) Kuhn) genets under grazing. Evolutionary Ecology. 2002, 15: 463-483.
[48]Conner, J. H. Diversity in tropical rain forests and coral reefs. Science. 1978,199:1302-1310.
[49]Conner, J. H. Social and economic influences on grazing management. In: Heitschmidt, R. K.; Stuth, J. W. (eds). Grazing management: An ecological perspective. Portland, Timber Press, 1991,p191-199.
[50]Coppolillo, P.B. Central-place analysis and modeling of landscape-scale resource use in an East African agropastoral system. Landscape Ecology .2001,16:205-219.
[51]Costanza R, Ralph d'Arge, Rudolf de Groot, et al. The value of the word's ecosystem services and natural capital. Nature.1997, 387:253-260.
[52]Craine, J.M.; D.A. Wedin; F.S. Chapin and P.B. Reich. Relationship between the structure of root systems and resource use for 11 North American grassland plants. Plant Ecology.2002, 165:85-100.
[53]Crawford, A. K. and Liddle, M. J. The effects of trampling on neutral grassland. Biological Conservation. 1977, 12:35-42.
[54] Cumming, H. M.; Cumming, G. S. Ungulate community structure and ecological processes: body size, hoof area and trampling in African savannas. Oecologia.2003, 134:560-568
[55] Dahlman, R. D, Kucera, C. L. Root productivity and turnover in nature prairie. Ecology. 1965, 46:104-116.
[56] Dakhah, M.; Gifford, G. F. Influence of vegetation, rock cover and trampling on infiltration rates and sediment production. Water Resource Bull.1980, 16:979-986.
[57] Dasmarnn, W. A method for estimating carrying capacity of rangelandss. Journal of Forestry.1945, (43):400-402.
[58] Dawson, L. A.; S. J. Graystonl; P. J. Murray; R. Cook; A. C. Gange; J. M. Rossl; S. M. Prattl; E. I. Duff and A. Treonis. Influence of pasture management (nitrogen and lime addition and insecticide treatment) on soil organisms and pasture root system dynamics in the field. Plant and Soil.2003,255: 121-130.
[59] Decaens, T. Degradation dynamics of surface earthworm casts in grassland of the eastern plains of Colombia. Biology and Fertility of Soil. 2000,32(2): 149-156.
[60] DeLuca, T. H.; Patterson, W. A. ; Freimund, Ⅳ, W. A.and Cole, D. N. Influence of llamas, horses and hikers on soil erosion from established recreation trails in Western Montana. Environmental Management. 1998, 22:255-262.
[61] Desjardins, T.; Andreux, F.; Volkoff, B. Organic carbon and ~(13)C contents in soils and soil size-fractions, and their changes due to deforestation and pasture installation in eastern Amazonia. Geoderma.1994, 61:103-118.
[62] Dianfa, Z.; Nianfeng, L.; Jie , T. Formation mechanism of eco-geo-environmental hazards in the ago-pastoral interlocking zone of northern China. Environmental Geology. 2000, 39 (12): 1385-1390.
[63] Diddle, M. J. A selective review of the ecological effects of human trampling on natural ecosystems. Biological Conservation. 1975, 7:17-36.
[64] Donkor, N.T.; Bork, E. W. and Hudson, R. J. Bromus-Poa response to defoliation intensity and frequency under three soil moisture levels. Canadian Journal of Plant Science.2002, 82(11):365-370.
[65] Dormaar, J. F.; Adams, B. W.; Willms, B. D. 1994. Effects of grazing and abandoned cultivation on a Stipa-Bouteloua community, J. Rage. Manage. 1994, 47:28-32.
[66] Dormaar, J. F.;Smoliajk, S. Seasonal variation in chemical characteristics of soil organic matter of grassland, d. Range Manage. 1977, 30:195-198.
[67] Drewry, J. J. and R. J. Paton. Effects of sheep treading on soil physical properties and pasture yield of newly sown pastures. New Zealand Journal of Agricultural Research.2005, 48:39-46.
[68] Dumont B., Boissy A. Grazing behaving of sheep in a situation of conflict between feeding and social motivations. Behavioural Processes.2000, 49:131-138.
[69] Dyer, M. I. The effects of Red winged Blackbirds (Agelaius phoeniceus L.) on biomass production of corn grains (Zea mays L.). Journal of Applied Ecology. 1975, 12:719-726.
[70] Dyer, M. I.;U. G. Bokhari. Plantanimal interactions: studies of the effects of grasshopper grazingn in blue grama grass. Ecology. 1976, 57:762-772.
[71] E. Klaghofer. 农业措施对地表径流和土壤侵蚀的影响．水土保持科技情报．1999，2：1-3．
[72]Edyy, M. and Argenta, T. Aboveground and belowground biomass relations in steppes under different grazing conditions.Oikos. 1989, 56:364-370.
[73]Eldridge, D.J.; Greene, R.S.B. Microbiotic soil crusts: a review of their roles in soil and ecological processes in the rangelands of Australia. Australian Journal of Soil Research. 1994,32:389-415.
[74]Eldridge, D.J.; Zaady, E.; Shachak, M. Microphytic crusts, shrub patches and water harvesting in the Negev Desert: the Shikim system. Landscape Ecology.2002,17(6):587-597.
[75]Eldridge, D.J; Koen, T.B. Cover and floristics of microphytic soil crusts in relation to indices of landscape health. Plant Ecology. 1998,137(1):101-114.
[76]Ellison, L. The influence of grazing on plant sucession . Botanical Review.1960,26:1-78.
[77]Evans,R. The erosional impacts of grazing animals. Progress in Physical Geography. 1998, 22(2):251-268.
[78]Fay,P.A.; Carlisle J.D.; Knapp, A.K.; Blair, J.M. and Collins, S.L. Productivity responses to altered rainfall patterns in a G_4-dominated grassland. Oecologia.2003, 137:245-251.
[79]Finlayson, J.D.; Betteridge, K.; MacKay, A.; Thorrold, B.; Costall, D.A. A simulation model of the effects of cattle treading on pasture production on Northern Island, New Zealand, hill land. New Zealand Journal of Agricultural Research.2002,45(2):255-272.
[80]Francis GS, Tabley FJ, White KM. Soil degradation under cropping and its influence on wheat yield on a weekly structured New Zealand silt loam. Australian Journal of Soil Research.2001, 39(2):291-305.
[81]Frank, A .B.; Tanakn, D.L. and Follett, R. E. Soil carbon and nitrogen of Northern Great plain grasslands as influenced by long-term grazing. Journal of Range Management. 1995,48(6):528-534.
[82]Frank, D. A.; Evans, R. D. Effects of native grazers on grassland N cycling in Yellewstone National Park. Ecology.1997, 78(7):2238-2248.
[83]Frank,D.A.; Groman,P.M. Denitrification in a semi-arid grazing cosystem. Oecologia. 1998,117:564-569.
[84]Franzluebbers A.J., Stueddemann J.A., Stueddemann J.A., Schomberg H.H. Spatial distribution of soil biochemical properties under grazed tall fescue. Soil Science Society of America Journal. 2000, 64:635-639.
[85]Fryrear, D. W. Soil cover and wind erosion. Trans. ASAE.1985,28(3):781-784.
[86]Fullen, M. A. Effects of grass ley set aside on runoff, erosion and soil organic matter levels in sandy soils in east Shropshire, UK. Soil & Tillage Research.1998, 46:41-49.
[87]Gallet S. and Roze F. Long-term effects of trampling on Atlantic Heathland in Brittany France: resilience and tolerance in relation to season and meteorological conditions. Biological Conservation.2002, 103: 267-275.
[88]Gallet, S., and F. Roze. Resistance of Atlantic Heathlands to trampling in Brittany (France): Influence of vegetation type, season and weather conditions. Biological Conservation.2001, 97:189-198.
[89]Gallet, S.; Lemauviel,S. and Rose, F.O. Responses of Three Heathland Shrubs to Single or Repeated Experimental Trampling. Environmental Management..2004, 33(6):821-829.
[90]Gao, X. J.; Zhao, Z. C.; and Ding, Y. H. Climate Change due to Greenhouse Effects in China as Simulated by a Regional Climate Model. Advances in Atmospheric Sciences. 2001,18:1224-1230.
[91]Gebeyehu, S.; Samways, M.J.Grasshopper assemblage response to a restored national park; Mountain Zebra National Park, South Africa. Biodiversity and Conservation. 2002, 11(2):283-304.
[92]Gibson, C. W. D.; Brown, V. K. Grazing and vegetation changes: deflected or modified succession ? Journal of Applied Ecology. 1992, 5 (29): 120-131.
[93]Gijsman, A.J. and Thomas, R.J. Evaluation of some physical properties of an oxisol after conversion of native Savanna into legume-based on pure grass pastures. Trop. Grasslands. 1996, 30:237-248.
[94]Gillingham, M.P.; Parker, K.L.; Hanley, T.A. Forage intake by black-tailed deer in a natural environment: bout dynamics. Canadian Journal of Zoology. 1997, 75(7): 1118-1128.
[95]Grace, J. B. On the measurement of plant competieiton intensity. Ecology. 1995, 76(1): 305-308.
[96]Graetz D. Grasslands. In: Changes in Land Use and Land Cover: a Global Perspective (eds W. B. Meyer & B. L. Turner, Ⅱ), pp. 125-147. Cambridge: Cambridge University Press. 1994.
[97]Greene,R.S.B.;Kinnell,P.I.A.;Wood,J.T. Role of plant cover and stock trampling on runoff and soil erosion from semi-add wooded rangelands. Aus.J.Soil Res. 1994, 32:953-973.
[98]Greenwood, EB.; Mcnamara, R.M. An analysis of the physical condition of two intensively grazedSouthland soils. Proceedings of the New Zealand Grassland Association. 1992, 54:71-75.
[99]Greenwood, P.B.;Macleod, D.A. and Hutchinson,K.J. Long-term stocking rate effects on soil physical properties. Australian. J. of Experimental Agriculture.1997, 37:413-419.
[100]Grime, J. P. Competitive exclusion in herbaceous vegetation. Nature. 1973, 242:344-347.
[101]Grime, J. P. Evidence for the existence.of three primary strategies in plants and its relevance to ecological and evolutionary theory, American Naturalist. 1977, 111:1169-1194.
[102]Gross K.L., Willig M.R., Gough l., Inouye R., Cox S.B. Patterns of species diversity and productivity at different spatial scales in herbaceous plant communities. Oikos. 2000, 89:417-427
[103]Guerif, J. Factors influencing compaction-induced increases in soil strength. Soil & Tillage Reaserch. 1990, 16:167-178.
[104]Guethery, F. S. and Bingham, R. L. A theoretical basis for study and management of trampling cattle. J. Range. Manage.1996,49:264-269.
[105]Hadwen,S. and Palmer, L. J. Reindeer in Alaska. USDA Bulletin. No. 1089. Washington, D. C.: US Department of Agriculture. 1922.
[106]Hall, D. O.;Ojima, D.S.;Parton, W.J. and Scuilock, J.M.O. Response of temperate and tropical grasslands to CO_2 and climate change, Journal of Biogeography. 1995,22:537-547.
[107]Hansson, A.C. and Andren, O. Below-ground plant production in a perennial grass ley assessed with different methods. J. of Appl. Ecol. 1986, 23:56-67.
[108]Harper, J.L. Population Biology of Plants. Academic Press, London. 1977.
[109]Harris, R.A.; Jones, R.M.; Rook, A.J.; Penning, P.D. The Loft and Hill of White Hamars Grazing Project. In Penning PD (ed.): Proceedings of the British Grassland Society Conference. 2000,157-158.
[110]Hart, R.H. A simple model to assess range technology. J. Range Manage. 1989, 42:421-424.
[111]Hart, R.H.; Bissio, J.; Samuel, M.J. and Waggoner, J. W. Grazing systems, pasture size, and cattle grazing behavior, distribution and gains. J. Range Manage. 1993a, 46:81-87.
[112]Hart, R.H.; Clapp, S. and Test, P. S. Grazing strategies, stocking rates, and frequency and intensity of grazing on western wheatgrass and bluegrass. J. Range Manage. 1993b, 46:122-126.
[113]Hart, R.H.; Samuel, M. J.; Test, P. S. and Smith, M. A. Cattle, vegetation and economic responses to grazing systems and grazing pressure. J. Range Manage. 1988,41:282-286
[114]Hartge,K.H. Stress distribution in the solid phase of soils.Soil Technology. 1993,6:83-87.
[115]Hassell, M.P. and Wilson, H.B. The dynamics of spatially distributed host-parasitoid systems. In: D. Tilman and P. Kareiva (eds), Spatial Ecology: the Role of Space in Population Dynamics and Interspecific Interactions. Princeton University Press, Princeton, pp.75-110.1997.
[116]Hertz,J.A.;Krogh,A.S.;Palmer,R.G Introduction to the Theory of Neural Computation. Addison Wesley, Redwood City, CA.,1991. p115-162,217-227.
[117]Hiernaux P, Bielders CL, Valentin C, Bationo A, Fernandez Rivera S. Effects of livestock grazing on physical and chemical properties of sandy soils in Sahelian rangelands. Journal of Arid Environments. 1999,41(3):231-245.
[118]Hill, M. O.; Evans, D. F.; Bell, S. A. Longterm effects of excluding sheep from hill pastures in North Wales. Journal of Ecology. 1992 , 80:1-13.
[119]Hillel, D. Soil and Water: Physical Principles and Processes. 1971.
[120]Hobbs, R. J. Disturbances as a precursor for weed invasion in native vegetation. Plant Protection Quarterly.1991,8:99-104.
[121]Hodgson J. Grazing Managemnt- Science into Practice. New York :Longman Science and Technical Press. 1990.
[122]Hodgson, J.; Illius, A. W. The ecology and management of grazing systems. CABI, Oxon, UK, 1995.
[123]Holland, E. A.; Detling, J. K. Plant-response to herbivory and belowground nitrogen cycling. Ecology. 1990,71:1040-1049.
[124]Holt, J. A. Grazing pressure and soil carbon, microbial biomass and enzyme activities in semi-arid northeastern Australin.Appl.. Soil Ecol. 1997,5:143-149.
[125]Holt, J.A.; Bristow, K.L and McIvor, J.G The effects of grazing pressure on soil animals and hydraulic properties of two soils in semi-arid tropical Queensland. Aust. J. Soil Res. 1996,34:69-79.
[126]Hood, L.; Morgan, J.K. Whose home on the range? Sierra Club Bull. 1972, 57:4-11.
[127]Hopkins, A. and Wainwright, J. Change in botanical composition and agricultural management of enclosed grass land in upland areas of England and Wales, 1970-1986, and some conservation implications. Biological Conservation.1989,47:219-235.
[128]Horgan, G.W. Mathematical morphology for analyzing soil structure from images. European Journal of Soil Science. 1998, 49:161-173.
[129]Horn, R.; Domzal, H.; Slowinska-Jurkiewicz, A. and Ouwerkerk, C. Soil compaction processes and their effects on the structure of arable soils and the environment. Soil Till. Res. 1995, 35:23-36.
[130]Huang Chihua, Zheng Fenli. Research Progress on Soil Erosion Process and Erosion Predction Model in the USA.水土保持通报.2003,23(3): 1-5.
[131]Hui Long Lin, Qi Ming Zhuang. Adaptive extent and seed yield predictions for Microula sikkimensis grown in the Qinghai-Tibet Plateau, China. Ecological modelling 201 (2007) 507-520.
[132]Huilong LIN, Jizhou REN, and Qin WANG. Seed yield predictions based on the habitat niche-fitness of Microula sikkimensis, an endemic oil crop in the Qinghai-Tibet Plateau. Botanical Studies.2006,47: 291-306.
[133]Hunt, L.P. Low seed availability may limit recruitment in grazed Atriplex vesicaria and contribute to its local extinction. Plant Ecology. 2001, 157(1):53-67.
[134]Hylgaard,T.and Liddle,M.J. The effect of human trampling on a sand dune ecosystem dominated by Empetrum nigrum. Journal of Applied Ecology.1981, 18:559-569.
[135]Ian, J. R.; Benjamin, F. T. Disturbance persistence in managed grasslands: shifts in aboveground community structure and the weed seed bank. Plant Ecol.2006. DOI 10.1007/s11258-006-9191-7.
[136]Ikeda, H. and Okutomi, K. Effects of human trampling and multispecies competition on earlyphase development of a tread community. Ecological Research. 1990, 5:41-54.
[137]Ikeda, H. and Okutomi, K. Effects of species interactions on community organization along a trampling gradient. Journal of Vegetation Science. 1992, 3:217-222.
[138]Ikeda, H. and Okutomi, K. Effects of trampling and competition on plant growth and shoot morphology of Plantago, Eragrostis and Eleusine species. Acta Botanica Neerlandica. 1995, 44:151-160.
[139]Ikeda, H. Testing the intermediate disturbance hypothesis on species diversity in herbaceous plant communities along a human trampling gradient using a 4-year experiment in an old-field. Ecological Research.2003, 18:185-197.
[140]Imhoff, S.; Pires da Silva, A. and. Tormena, C.A Spatial heterogeneity of soil properties in areas under elephant-grass short-duration grazing system. Plant and Soil.2000, 219:161-168.
[141]Ingram, K.T. and Leers, GA. Software for measuring root characters from digital images.Agron.J.2001, 93:918-922.
[142]Jackson, L.L. Establishing tallgrass prairie on grazed permanent pasture in the Upper Midwest. Restoration Ecology.1999, 7(2):127-138.
[143]Jeffries, D. L. and Klopatek, J. M. Effects of grazing on the vegetation of the blackbrush association.J Range Manag. 1987, 40:390-392.
[144]John Frame. Improved grassland management. United Kingdom: Fanning Press.2000.
[145]John,C. C.and Joy,B.Z. Restoration of urban salt marshes: Lessons from southern California. Urban Ecosystems.2004, 7:107-124.
[146]Johnston, A.; Dormmar,J. F.; Smoliak, S. Long-term grazing effects on fescue grassland soils. Journal of Range Management. 1971, 24:185-188.
[147]Jordan, D.; Ponder, F.; Hubbard, V. C. Effects of soil compaction, forest leaf litter and nitrogen fertilizer on two oak species and microbial activity. Appl. Soil Ecol.2003, 23:33-41.
[148]Keller, A. A.; Goldstein, R. A. Impact of carbon storage through restoration of dry lands on the global carbon cycle. Environ. Manage. 1998, 22:757-766.
[149]Kemper, J.; Cowling, R.M.; Richardson, D.M. Fragmentation of South African renosterveld shrublands: effects on plant community structure and conservation implications. Biological Conservation.1999, 90(2): 103-111.
[150]Kepner, W.G.; Watts, C. J.; Edmonds, C. M.;Maingi, J.K.; Marsh, S.E.;Luna, G. A Landscape approach for detecting and evaluating change in a semi-arid environment. Environmental Monitoring and Assessment.2000, 64:179-195.
[151]Kim, J.G. The effects of cattle grazing on optimal foraging in mule deer (Odocoileus hemionus).Forest Ecology and Management. 1996, 88(1/2): 131-138.
[152]Kirkby, M.J.;Morgan,R.P.C. Soil erosion. John Wiley & Sons Ltd. 1980.
[153]Kleiner, E. F. & Harper, K. T. Soil properties in relation to cryptogamic ground cover in Canyonlands National Park. J. Range Manag. 1977, 30:203-205.
[154]Kobayashi, T.; Hori, Y. and Nomoto, N. Effects of trampling and vegetation removal on species diversity and microenvironment under different shade conditions. Journal of Vegetation Science.1997, 8(6): 873-880.
[155]Koc, A., Oztas, T., Tahtacioglu, L. Rangeland-livestock interaction in our near history: problems and recommendations. Proceedings of the International Symposium on Desertification, 13-17 June 2000, Konya, Turkey, pp.293-298.
[156]Kohler, F. Influence of grazing, dunging and trampling on short-term dynamics of grasslands in mountain wooded pasture. PhD Thesis, University of Neuchatel, Neuchatel, 2004.
[157]Kohler, F.; Gillet, F.; Gobat, J. M.; Buttler, A. Seasonal vegetation changes in mountain pastures due to simulated effects of cattle grazing. J. Veg. Sci.2004, 15:143-150.
[158]Kohler, F.; Hamelin, J.; Gillet, F.; Gobat, J.M.; Buttler, A. Soil microbial community changes in wooded mountain pastures due to simulated effects of cattle grazing. Plant and Soil.2005, 278:327-340.
[159]Koutika, L. S.; Andreux, F.; Hassink, J. Charactertration of organic matter in the topsoils under rain forest and pastures in the eastern Brazilinn Amazon basin. Biol. Fertil. Soils. 1999, 29:309-313.
[160]Kutiel P., Eden E. and Zhevelev Y. Effect of experimental trampling and off-road motorcycle traffic on soil and vegetation of stabilized coastal dunes, Israel. Environmental Conservation.2000, 27(1): 14-23.
[161]Lal, R. World soils and greenhouse effect. IGBP Global Change News letter.1999, 37:4-5.
[162]Lal, R.; Stewart, B.A. Soil degradation. New York: Springer-Verlag. 1990.
[163]Laska,G. The disturbance and vegetation dynamics: a review and an alternative framework. Plant Ecology. 2001,157: 77-99.
[164]Lauenroth, W.K. and Whitman, W.C. A rapid method for washing roots. J. Rang. Mang.1971, 24:37-42.
[165]Laycock W.A. and Conrad P.W. Effect of grazing on soil compaction as measured by bulk density on a high elevation cattle range. Journal of Range anagement. 1967, 20:136-140.
[166]Le Roux, X.; Bardy, M.; Loiseau, P.; Louault, F. Stimulation of soil nitrification and denitrification by grazing in grasslands: do changes in plant species composition matter? Oecologia.2003,137:417-425
[167]LeCain, D. R.; Morgan, J. A.; Schuman, G. E. Carbon exchange and species composition of grazed pastures and exclosures in the shortgrass steppe of Colorado. Agricultures Ecosystems & Environment. 2002, 93:421-435.
[168]Lehmann, A., Leathwick, J.R., Overton, J.McC., Assessing New Zealand fem diversity from spatial predictions of species assemblages. Biodivers. Conserv.2002a, 11:2217-2238.
[169]Lehmann, A; J. M.Overton and J. R. Leathwick. GRASP: generalized regression analysis and spatial prediction. Ecological Modelling.2002b, 157:189-207.
[170]Lemauviel, S., and F. Roze. Response of three plant communities to trampling in sand dune systems in Brittany (France). Environmental Management.2003, 31:227-235.
[171]Liddle M.J. A selective review of the ecological effects of human trampling on natural ecosystems. Biological Conservation. 1975, 7:17-36.
[172]Liddle M.J. Recreation Ecology. London: Chapman and Hall. 1997.
[173]Liddle, M. J. Recreation ecology: effects of trampling on plants and coral. Trends in Ecology and Evolution.1991, 6:13-17.
[174]Liddle, M. J. A selective review of the ecological effects of human trampling on natural ecosystems. Biological Conservation. 1975a, 7:17-36.
[175]Liddle, M. J. A theoretical relationship between the primary productivity of vegetation and its ability to tolerate trampling. Biological Conservation.1975b, 8:251-255.
[176]Liddle, M. J. and Barker, S. The ecological response of forest ground flora and soils to experimental trampling in British urban woodlands. Urban Ecosystems.2001, 5:257-276.
[177]Liddle,M.J. and Thyer,N,C.Trampling and fire in a subtropical dry sclerophyll forest.Environmental Conservation. 1986,13:33-39.
[178]Littlemore, J. Resolving conflicts between recreation and conservation in Britain's urban woodlands—a management guide. Quarterly Journal of Forestry.2001,95(2): 129-136.
[179]Lock,J.M. The effects of hippopotamus grazing on grasslands. Journal of Ecology. 1972,60:445-467.
[180]Malcolm B, Sale P, Egan A. Agriculture in Australia: an introdution. Melbourne: Oxford University Press. 1996,391-419.
[181]Malinda, D.K.; Facett, R.G.; Little, D.; Bligh, K. Darling, W. The effect of grazing, surface cover and tillage on erosion and nutrient depletion. Advances in Geoecology.1998, (31): 1217-1224.
[182]Malthus, R. Essay on the Principle of Population. Mew York: Phillip Applemaned. Norton, 1798. Reprinted 1976.p226.
[183]Mandelbrot, B.B. The Fractal Geometry of Nature. W H Freeman, New York, 1982.
[184]Maria, B. M.; Nilda, M. A.; Norman, P. Soil degradation related to overgrazing in the semi-arid southern Caldenal area of Argentina. Soil Science. 2001, 166 (7):441-452 .
[185]Maria, F.G.; Barbara, A.D. Vegetation change along gradients from water sources in three grazed Mongolian ecosystems. Plant Ecology..2001, 157( 1): 101 -118.
[186]Marion,J.L.and Cole, D.N. Spatial and temporal variation in soil and vegetation impacts on campsites'. Ecological Applications.1996, 6(2):520-530.
[187]Maron J.L.and Gardner, S.N.Consumer pressure, seed versus safe-site limitation, and plant population dynamics. Oecologia.2000, 124:260-269.
[188]Marshall, J.K. Drought, land use and soil erosion. In: Lovett, J.V. (Ed.), In the Environmental, Economic and Social Significance of Drought. Angus and Robertson Publ., Inc., London, 1973.pp. 55-77.
[189]Martin, K; Ralf, C. Effect of CH_4 concentrations and soil conditions on the induction of CH_4 oxidation activity . Soil Biology and Biochemistry, 1995,27:1517-1527.
[190]Martinez, L. J.; Zinck, J. A. Temporal variation of soil compaction and deterioration of soil quality in pasture areas of Colombian Amazonia. Soil Till. Res.2004,75, 3-17.
[191]Mayer, A.C.; Stocklil, V.; Konold, W.; Kreuzer, M. Influence of cattle stocking rate on browsing of Norway spruce in subalpine wood pastures. Agroforestry Systems.2005, 34:33-41.
[192]McCalla, G.R.; Blackburn, W.H.and Merrill,L.B. Effects of livestock grazing on infiltration rates, Edwards Plateau of Texas. J. Range Manage.1984, 37:265-269.
[193]McConnell, S. G.; Quinn, M. L. Soil productivity of four land use systems in southeastern Montana. Soil Science Society of America Journal.1988, 52:50-56.
[194]Mclntire, E. J. B.; Hik, D. S. Grazing history versus current grazing: leaf demography and compensatory groeth of three alpine plants in response to a native herbivore (Ochotona collaris). Journal of Ecology. 2002,90(2):348-359.
[195]McNaughton, S. J. Compensatory plant growth as a response to herbivory. Oikos.1983,40:329-336.
[196]McNaughton, S. J. Grazing as an optimisation process: grassungulate relationships in the Serengti. American Naturalist. 1979, 5:691-703.
[197]McNaughton, S. J. Serengeti migratory wildebeest facilitation of energy flow by grazing.Science. 1976,191: 92-94.
[198]McNaughton, S. J.; F. S.Chapin. Effects of phosphorus nutriton and defoliation on C4 graminoids from the Serengeti plants. Ecology. 1985, 66:1617-1629.
[199]McNaughton, S.J. Ranyikwa, F.F., and McNaughton, N.M. Root biomass and productivity in grazing ecosystem: the Sorengeti.Ecology.1998, 79(2):587-592.
[200]Meyer, L. D. Evolution of the Universal Soil Loss Equation. J. Soil and Water Cons. 1984, 32(2):99-104.
[201]Milchunas, D. G.; Laurenorth, W. K. Quantitative effects of grazing on vegetation and soils over a global range of environments. Ecological Monographs. 1993, 63(4):327-366.
[202]Milchunas, D. G.; Sala, O. E. and Lauenroth, W. K. A generaltred model of the effects of grazing by large herbivores on grassland community structure. American Naturalist.1988, 132:87-106.
[203]Mitchell, C .A.; Custer, T. W.; Zwank, P. J. Herbivore on short grass by wintering redheads in Texas. Journal of Wildlife Management.1994, 58:131-141.
[204]Monz, C. A. The responses of two arctic tundra plant communities to human trampling disturb bance.Journal of Environmental Management. 2002, 64:207-217.
[205]Morgan, R. P. C.; Quinton, J. N.; Smith, R. E.. The European Soil Erosion Model (EU ROSEM ): A dynamic approach for predicting sediment transport from fields and small catchments. Earth Surface Processes and Land forms..1998,23(6):527-544.
[206]Murphy, W. M.; Barreto, A. D.; Silman, J. P. and Dindal, D. L. Cattle and sheep grazing effects on soil organisms, fertility and compaction in a smooth-stalked meadowgrass-dominant white clover sward. Grass Forr. Sci.1995, 50:191-194.
[207]Mwendera, E.J.; Saleem, M.A.M. Hydrologic response to cattle grazing in the Ethiopian highlands. Agric Ecosyst Environ. 1997, 64:33-41.
[208]Naeth, M. A.; Bailey, A. W.; Pluth, D. J.. Grazing impacts on litter and soil organic matter in mixed prairie and fescue grassland ecosystems of Alberta. J. Range Manage. 1991,44(1):7-12.
[209]Nash, T. H., White, S. L. & March, J. E. Lichen and moss distribution and biomass in hot desert ecosystems. Bryologist. 1977, 80:470-479.
[210]Nearing, M. A.; Foster, G. R.; Lane, L. J., A process-based soil erosion model for USDA-Water Erosion Prediction Project Technology. Trans.ASAE. 1989, 32:1587-1593.
[211]Nguyen, M.L.; Sheath, G.W.; Smith, C.M.; Cooper, A.B. Impact of cattle treading on hill land, 2. soil physical properties and contaminant runoff. New Zealand Journal of Agricultural Research.1998, 41(2):279-290.
[212]Ni, J.Carbon storage in grasslands of China. Journal of Arid Environmenis.2002, 50:205-218.
[213]Nie, Z.N.; Mackay, A.D.; Valentine, I.; Barker, D.J. and Hodgson, J. Influence of pastoral fallow on plant root growth and soil physical and chemical characteristics in a hill pasture. Plant and Soil.1997,197: 201-208.
[214]Noble, I. R., and R. O. Slatyer. The use of vital attributes to predict successional changes in plant communities subject to recurrent disturbances. Vegetatio.1980, 43:5-21.
[215]Olff, H.; Vera, F. W. M.; Bokdam. J.; Bakker, E. S.; Gleichman, J. M.; de Maeyer, K. and Smit, R. Shifting mosaics in grazed woodlands driven by the alternation of plant facilitation and competition. Plant Biol. 1999,1:127-137.
[216]Olson and Wischmeier. Soil erodibility evaluation for soils on the runoffand erosion stations.Soil Science. 1963, 27 (5):590-592.
[217]Orr H.K. Soil porosity and bulk density on grazed and protected bluegrass range in the Black Hills. Journal of Range Management.1960, 13:80-86.
[218]Owen, D. F.; R. G. Wiegert. Do consumers maximise plant fitness.Oikos. 1976, 27:488-492.
[219]Owen, D. F.; R. G. Wiegert. Mutualism between grasses and grazers: an evolotionary hypothesis. Oikos. 1981, 36:376-378.
[220]Owens，L．B．牧地围栅对径流泥沙的影响．水土保持科技情报．1996，3：36—38．
[221]Oztasa, T.; Kocb,A.; Comakli, B. Changes in vegetation and soil properties along a slope on overgrazed and eroded rangelands. Journal of Arid Environments.2003, 55:93-100.
[222]Pakeman RJ, Thwaites RH, Duc MG le, Marrs RH. Vegetation re-establishment on land previously subject to control of Pteridium aquilinum by herbicide. Applied Vegetation Science.2000, 3(1):95-104.
[223]Perevoznikova, V. D. and Zubareva, O. N. Geobotanical Indication of the State of Suburban Forests. Russian Journal of Ecology.2002, 33 (1): 1-6.
[224]Perfect, E.; Kay, B.D. Fractal theory applied to soil aggregation. Soil Sci Soc Am J. 1991, 55:1552-1558.
[225]Perfect, E.; Rasiah, V.; Kay, B.D. Fractal dimensions of soil aggregate—size distributions calculated by number and mass. Soil Sci Soc Am J. 1992, 56:1407-1409.
[226]Perfect, E; Kay, B.D.; Rasiah, V. Multifractal model for soil aggregate fragmentation. Soil Sci Soc Am J. 1993, 57: 896-900.
[227]Peter, B. A. and Sonia, A. H. The development of forage production and utilization gradients around livestock watering points. Landscape Ecology .2005,20:319-333.
[228]Pimentel, D. (ed.). World soil erosion and conservation. Cambridge: Cambridge University Press. 1993.
[229]Pimentel, D.; Harvey, C.; Resosudarmo, P.; Sinclair, K.; Kurz, D.; McNair, M.; Crist, S.; Sphpritz, L.; Fitton, L.; Saffouri, R.; Blair, R. Environmental and economic costs of soil erosion and conservation benefits. Science. 1995,267:1117-1123.
[230]Pimentel, D.and Kounang, N. Ecology of Soil Erosion in Ecosystems. Ecosystems.1998, 1:416-426.
[231]Priskin,J. Tourist Perceptions of Degradation Caused by Coastal Nature-Based Recreation. Environmental Management.2003, 32(3): 189-204.
[232]Proffitt, A. P. B.; Bendotti, S.; McGarry, D. A comparison between continuous and controlled grazing on a red duplex soil. 1. Effects on soil physical characteristics. Soil & Tillage Research.1995, 35:199-210.
[233]Proffitt, A.P.B.; Jarvis, R.J. and Bendotti, S. The impact of sheep trampling and stocking rate on the physical properties of a red duplex soil with two initially different structures. Australian Journal of Agricultural Research.2005,46(4):733-747
[234]Rasanen, S. Tracing and interpreting fine-scale human impact in northern Fennoscandia with the aid modern pollen analogues. Vegetation History and Archaeobotany.2001, 10(4):211-218.
[235]Rasiah, V.; Kay, B.D.; Perfect, E. Evaluation, of selected factors influencing aggregate fragmentation using fractal theory. Canada J Soil Sci.1992, 72:97-106.
[236]Rasiah, V.; Kay, B.D.; Perfect, E. New mass based model for estimating fractal dimensions. Soil Sci Soc Am J.1993,57:891-895.
[237]Reeder,J .D.; Gerald, E. Schuman,G.E.; Morgan,J.A.; Lecain,,D.R. Response of Organic and Inorganic Carbon and Nitrogen to Long-Term Grazing of the Shortgrass Steppe. Environmental Management. 2004, 33(4):485-495.
[238]Reeder,J .D.; Schuman, G. E. Influence of livestock grazing on C sequestration in semi- arid mixed-grass and short-grass rangelands.Environment Pullution.2002, 116:457-463.
[239]Renard, K.G.; Foster,G.R.; Weesies, G.A. Predicting soil erosion by water: A guide to conservation planning with the Revised Universal Soil Loss Equation(RUSLE). Agricultural Handbook No.537, United States Department of Agriculture, Washington. 1997.
[240]Rezende, C. P.; Cantarutti, R.B.; Braga, J.M.; Gomide, J.A.; Pereiral, J.M. ; Ferreira, E. ; Tarr'e, R.; Macedo, R.; Alves, B.J.R.; Urquiaga, S.; Cadisch, G.; Giller, K.E. and Boddey, R.M. Litter deposition and disappearance in Brachiaria pastures in the Atlantic forest region of the South of Bahia, Brazil. Nutrient Cycling in Agroecosystems.1999, 54:99-112.
[241]Ritche, M.E. Herbivore effects on plant and nitrogen dynamics in oak savanna.Ecology.1998, 79(1): 165-177.
[242]Rodgers,K.;Cox,E. and Newtson,C.Effects of mechanical fracturing and experimental trampling on Hawaiian Corals. Environmental Management .2003, 31(3):377-384.
[243]Rogers, R. W. & Lange, R. T. Lichen populations on arid soil crusts around sheep watering places in South Australia. Oikos.1971, 22:93-100.
[244]Romulo, S. C. M.; Edward, T .E.; David, W. V.; Stephen, A. W. Carbon and nitrogen dynamics in elk winter ranges. Journal of Range Management.2001, 54:400-408.
[245]Roovers,P.; Baeten,S. and Hermy,M. Plant species variation across path ecotones in a variety of common vegetation types. Plant Ecology.2004, 170:107-119.
[246]Roux, X.L.; Bardy, M.; Loiseau, P.; Louault, F. Stimulation of soil nitrification by grazing in grasslands: do changes in plant species composition matter? Oecologia.2003, 137(3):417-425.
[247]Sada, D.W. Demography and habitat use of the Badwater snail (Assiminea infima), with observations on its conservation status, Death Valley National Park, California, U.S.A. Hydrobiologia.2001,466: 255-265.
[248]Sampson, A. W. Range and Pasture Management. New York: John Wiley & Sons. 1923. p328.
[249]Savory, A. and Parson, S. D. The Savory grazing method. Rangeland 1980, (2):234-237.
[250]Savory, A. Holistic Resource Management. Covel, Calif: Island Press. 1988
[251]Savory, A. The Savory grazing method or holistie resource mangement. Rangeland. 1983, (5): 155-159.
[252]Schimel, D.; House, J. Hibbard, K. Recent patterns and mechanisms of carbon exchange by terrestrial ecosystems. Nature.2001,414:169-172.
[253]Schlaepfer, M.; Zoller, H.; Koerner, C. Influences of mowing and grazing on plant species composition in calcareous grassland. Bot. Helv.1998, 108:57-67.
[254]Schlesinger, W.H. Carbon balance in terrestrial detritus.Annual Review on Ecological System.1977, 8:51-81.
[255]Schlesinger, W.H.Biogechemistry:an analysis of global change.San diego,California:Academic Press. 1997.pp:5-50.
[256]Schuman, G. E.; Reeder, J. D.; Manley, J. T. Impact of grazing management on the carbon and nitrogen balance of a mixed-grass rangeland. Ecological Applications. 1999,9(1):65-71.
[257]Scurlock, J.M.O.;Johnson, K.;Qlson. R.J. Estimating net primary productivity from grassland biomass dynamics measuremenis. Gobal Change Biolog.2002, 8:736-753.
[258]Scurlock, J.M.O.;Hall, D.O.The global carbon sink: a grassland perspective. Gobal Change Biolog. 1998, 4:229-233.
[259]Seitlheko, E.M.; Allen, B.L.; Wester, D.B. Effect of three grazing intensities on selected soil properties in semi-arid west Texas. African Journal of Range and Forage Science.1993, 10(2):82-85.
[260]Shao, Y. P.; Raupach, M. R.; Leys, J. F. A model for predicting Aeolian sand drift and dust entrainment on scales from pad-dock to region. Australian Journal of Soil Research.1996, 34:309-342.
[261]Shariff, A.R.; Biondini, M. E.; Grygiel, C. E. Grazing intensity effects on litter decomposition and soil nitrogen mineralization. J.of Range Management. 1994, 47:444-447.
[262]Sharply, A. N.; J. R. Williams. EPIC-Erosion/Productivity Impact Calculator: 1. Model Documentation. US Department of Agriculture Technical Bulletin, No. 1968, 1990.
[263]Sheldrick, B.H.; Wang, C. Particle size distribution. In: Carter, M.R.(eds). Soil Sampling and Methods of Analysis. Canadian Society of Soil Science. Boca Raton, FL: Lewis Publishers, Division of CRC Press. 1993,p499-511;
[264]Silva, A.P.; Imhoff, S.; Corsi, M. Evaluation of soil compaction in an irrigated short-duration grazing system. Siol and Tillage Research.2003, 70(1):83-90.
[265]Society for Range Management. A Glossary of Terms Used in Range Mangement. Edison Press, Denver, Colorado, USA: Society For Range Management. 1964.p1-24.
[266]Society for Range Management. A Glossary of Terms Used in Range Mangement. 3rd edition. Complied by Jacoby,P.W. Edison Press, Denver, Colorado,USA:Society For Range Management, 1989.p1-36.
[267]Sperber, T.D.; Wraith, J.M. and Olson, B.E. Soil physical properties associated with the invasive spotted knapweed and native grasses are similar. Plant and Soil.2003, 252:241-249.
[268]Steen, E.Root biomass in timothy and red clover leys estimated by soil corning and mesh bags.J. of Agri.Sci. 1989,113:578-580.
[269]Stephenson, G.R.; Veigel, A. Recovery of compacted soil on pastures used for winter cattle feeding. Journal of Range Mangement. 1987,40(1):253-257.
[270]Sun, D. and Liddle, M. J. A survey of trampling effects on vegetation and soil in eight tropical and subtropical sites. Environ. ManageA993a, 17:497-510.
[271]Sun, D. and Liddle, M. J. Field occurrence, recovery and simulated trampling resistance and recovery of two grasses. Biol. Conserv. 1991, 57:187-203.
[272]Sun, D. and Liddle, M. J.The morphological and the importance of tiller number in their resistance to trampling. Biol. Conserv. 1993b, 65:43-50.
[273]Sun, D., and D. Walsh. Review of studies on environmental impacts of recreation and tourism in Australia. Journal of Environmental Management.1998, 53:323-338.
[274]Sutherland,R.A.;Bussen,J.O.;Plondke,D.L.;Evans,B.M.;Ziegler,A.D. Hydrophysical degradation associated with hiking-trail use:A case study of Hawai'iloa ridge trail, O'ahu, Hawai'i. Land Degradation & development 2001, 12:71-86.
[275]Taddese,G.; Saleem, M. A. M.; Abyie. A. et al. Impact of grazing on plant species richness, plant biomass, plant attribute and soil physical and hydrological properties of Vertisol in East African Highlands. Environmental Management,.2002, 29(2):279-289.
[276]Talbot, L.M.; Turton S.M.; Graham A.W. Trampling resistance of tropical rainforest soils and vegetation in the wet tropics of north east Australia. Journal of Environmental Management. 2003,69 (1):63-69.
[277]Thomas,D.S.G. The biogeomorphology of arid and semi-arid environments.In:Viles, H.A.(Ed.), Biogemorphology. Blackwell, Oxford,1988,pp365.
[278]Tilman, D.; Downing, J.A. Biodiversity and stability in grasslands. Nature.1994, 5:363-367.
[279]Torn, M. S.; Trumbore, S. E.; Chadwick, O. A . Mineral control of soil organic carbon storage and turnover. Nature.1991, 389:170.
[280]Torn,A.;Rautio,J.;Norokorpi,Y. and Tolvanen,A. Revegetation after short-term trampling at Subalpine heath vegetation. Ann.Bot.Fennici.2006,43:129-138.
[281]Tureotte, D.L. Fractal fragmentation model of soil aggregation. J Geography Res.1993, 91(12):1896-1899.
[282]Turner, M. G. Effects of grazing by feral horses, clipping, trampling, and burning on a Georgia salt marsh. Estuaries. 1987,10:54-60.
[283]Tyler, S.W.; Wheatcraft, S.W. Application of fractal mathematics to soil water retention estimation. Soil Sci Soc Am J.1989, 153:987-996
[284]Tyler, S.W.; Wheatcraft, S.W. Fractal process in soil water retention. Water Resour Res. 1990a, 26:1047-1054.
[285]Tyler, S.W.; Wheatcraft, S.W. Fractal scaling of soil particle-size distributions: analysis and limitations. Soil Sci Soc Am J. 1990b, 56:362-369.
[286]Upchurch, D.R. and Ritchie, J.T. Root observations using a video recording system in minirhizotrons. Agron.J. 1983, 76:1009-1015.
[287]Wal, R.V.; Suzan, M.J.; van Lieshout, Maartent, J.J. Loonen, E Herbivore impact on moss depth, soil temperature and arctic plant growth. Polar Biology.2001, 24(1):29-32.
[288]Wallace L. L. Effects of clipping and soil compaction on growth, morphology, and mycorrhizal colonization of Schizachyrium scoparium, a C_4 bunch grass. Oecologia. 1987, 72:423-428.
[289]Wallace, L. L. Effects of clipping and soil compaction on growth, morphology, and mycorrhizal colonization of Schizachyrium scoparium, a C_4 bunch grass. Oecologia. 1993, 72:423-428.
[290]Wallsce, L; Dyer, M. I. Grassland management. Ecosystem maintenance and Grazing. In: Joern, T.; Keeler, K.(eds). The changing Prarie. Oxford Press,New york. 1995.
[291]Wang, X.; Dong, Z.B.; Zhang, J.W. and Liu, L.C. Modern dust storms in China: an overview. Journal of Arid Environments.2004, 58:559-574.
[292]Wang, Y. S.; Hu, Y. Q.; Ji, B. M.. An investigation on the relationship between emission/uptake of greenhouse gases and environmental factors in semiarid grassland. Advances in Atmospheric Sciences.2003, 20(1): 119-127.
[293]Wang, Y. S.; Ji, B. M.; Huang. Effects of grazing and cultivating on emission of nitrous oxide, carbon dioxide and uptake of methane from grasslands. Environmental Science.2001, 22(6):7-13.
[294]Warren, S. D.; Nevill, M. B.; Blackburn, W.H. and Garza, N.E. Soil response to trampling under intensive rotation grazing. Soil Science Society of America Journal. 1986, 50:1336-1341.
[295]Wasson, R. J.; Nanninga, P. M. Estimation wind transport sand on vegetated surface. Earth Surface Processes and Landforms.1986, 11:505-514.
[296]Waterman W.G. Development of root systems under dune conditions. Botanical Gazette. 1919, 68:22-53.
[297]Weaver J.E. and Bruner W.E. A seven-year quantitative study of succession in grassland. Ecological Monographs 1945, 15:298-319.
[298]Weaver J.E. and Darland R.W. A method of measuring vigor of range grasses. Ecology. 1947, 28:146-162.
[299]Weaver J.E. and Darland R.W. Soil-root relationships of certain native grasses in various soil types. Ecological Monographs 1949, 19:303-338.
[300]Weaver J.E. and Zink E. Annual increase of underground materials in three range grasses. Ecology. 1946a, 27:115-127.
[301]Weaver J.E. and Zink E. Length of life of roots often species of perennial range and pasture grasses. Plant Physiology. 1946b, 21:201-217.
[302] Weaver J.E. Investigation on the root habitats of plants. America Journal Botany. 1925, 12:502-509.
[303] Weaver J.E. Prairie Plants and their Environment: a fifty year study in the Midwest. University of Nebraska Press. 1968.
[304] Weaver J.E. Rate of decomposition of roots and rhizomes of certain range grasses in undisturbed prairie soil. Ecology. 1947,28:221-240.
[305] Weaver J.E. Summary and interpretation of underground development in natural grassland communities. Ecological Monographs. 1958b, 28:55-78.
[306]Weaver J.E., Hougen V.H. and Weldon M.D. Relation of root distribution to organic matter in prairie soil. Botanical Gazette. 1935a, 96:389-420.
[307] Weaver J.E., Jean F.C. and Crist J.W. Development and activities of roots of crop plants. Washington: Carnegie Inst. 1922.
[308]Weaver J.E., Stoddart L.A. and Noll W. Response of the prairie to the great drought of 1934. Ecology. 1935b, 16:612-629.
[309]Weaver J.E.. Classification of root systems of forbs of grassland and a consideration of their significance. Ecology. 1958a, 39:393-401.
[310]Weigel, J. R.; Britton, C. M. Mepherson, G R. Trampling effects from short- duration grazing on tobo sagrass range. Journal of Range management.1990,43(2):92-95.
[311]Westoby, M.; Walker, B.; Noy-meir. Opportunistic management for rangelands not at equilibrium. Journal of Range Management. 1989,42(4):266-274.
[312]Whalley, W. R.; Dumitru, E.; Dexter, A. R. Biological effects of soil compaction.Soil Till. Res.1995, 35:53-68.
[313]Whinam J. and Chilcott N. Impacts of trampling on alpine environments in central Tasmania. Journal of Environmental Management. 1999, 57:205-220.
[314]Whinam,J. and Chilcott,N.M. Impacts after four yeaers of experimental trampling in alpine/sub-alpine environment in western Tasmania. Journal of Environmental Management.2003,67:339-351.
[315]Whitecotton,R.C.A.;David,M.B.;Darmody,R.G. and Price,D.L. Impact of Foot Traffic from Military Training on Soil and Vegetation Properties. Environmental Management .2000,26(6):697-706.
[316]Wienhold, B. J.; Hendrickson, J. R.; Karn, J. F. Pasture management influences on soil properties in the Northern Great Plains. J. Soil and Water Conserv.2001, 56(1):27-31.
[317]Willatt, S.T. and Pullar, D. M. Changes in soil physical properties under grazed pastures. Aust. J. Soil Res. 1983.22,343-348.
[318] Winkel V K, Roundy B A, Blough D K. Effects of seedbed preparation and cattle trampling on burial of grass seeds. Journal of Range Management. 1991 a, 44(2): 171 -175.
[319]Winkel, V. K.; Roundy, B. A. Effects of cattle trampling and mechanical seedbed preparation on grass seedling emergence. Journal of Range Management. 1991b, 44(2): 176-180.
[320]Winter,S.R.; Unger, P.W. Irrigated wheat grazing and tillage effects on subsequent dryland grain sorghum production. Agronomy Journal. 2001,93(3):504-510.
[321]Wischmeier, W. H. Use and misused of the universal soil loss equation. J Soil and Water Cons. 1976, 31 (1):5-9.
[322]Wischmeier, W. H.; Smith, D. D. A universal soil loss equation to guide conservation farm planning. Soil Sci. 1960, 1:418-425.
[323]Wischmeier, W.H.; Smith, D.D. Predicting rainfall erosion losses.A guide to conservation planning. U. S. Department of Agriculture, Agriculture Handbook. 1978.
[324]Wischmeier, W.H.; Smith, D.D. Predicting rainfall- erosion losses from cropland east of the Rocky Mountains: A guide for selection of practices for soil and water conservation. U. S. Department of Agriculture, Agriculture Handbook. 1965.
[325]Woodruff, N. P.; Siddoway, F. H. A wind erosion equation. Soil Science Society of America Proceedings. 1965, 29(5):602-608.
[326]Woodward, S. J. A simple model for optimizing rotational grazing.Agricultural System.1993, 41:123-155.
[327]Xu-Ri, Yuesi Wang, Xunhua Zheng, Baomin Ji and MingxingWang. A comparison between measured and modeled N_2O emissions from Inner Mongolian semi-add grassland.Plant and Soil.2003, 255: 513-528.
[328]Yue Depeng, Liu Yongbing, Zang Runguo, Wang Xian. Regularities of wind-erosion of different land-use types in Yongding River sandy land, Beijing. Front. For. China.2006, 2:208-213.
[329]Zacheis, A.; Hupp, J.W.; Ruess, R. Effects of migratory geese on plant communities of an Alaskan salt marsh. Journal of Ecology. 2001, 89(1):57-71.
[330]Zacheis, A.; Ruess, R.W.; Huup, J.W. Nitrogen dynamics in an Alaskan salt marsh following spring use by geese. Oecologia. 2002, 130(4): 600-608.
[331]安渊，徐柱，阎志坚．不同退化梯度草地植物和土壤的差异．中国草地．1999，4：31—36．
[332]安渊，陈丽君，孟慧琳．不同践踏强度对沟叶结缕草坪用性状的影响．．草地学报．2005，13(4)：299-303．
[333]安渊，陈丽君，孟慧琳，孙明，杨晓光．封闭时间对模拟践踏的沟叶结缕草草坪质量的影响．草业学报．2006，15(6)：81-86．
[334]敖特根，李勤奋．内蒙古草地风蚀状况与影响其主要自然因素．内蒙古草业．2001，1：31-34．
[335]白可喻，韩建国，王培．放牧强度对新麦草土壤氮素分配及其季节动态的影响．草地学报．1999b，7(4)：308-318．
[336]白可喻，王培，韩建国．放牧强度对新麦草人工草地氮素在牧草与土壤中的分配和动态的影响．草地学报．1999a，7(3)：46-53．
[337]白文明，程维信，李凌浩．微根窗技术及其在植物根系研究中的应用．生态学报．2005，25(11)：3076-3081．
[338]白云飞．降水量的季节分配对羊草草原群落地上部分生物量的影响的数学模型．草业学报．1997，2：15-24．
[339]北京体育学院编．运动生物力学．北京：人民教育出版社．1981．
[340]卜兆宏，刘绍清．土壤流失量及其参数实测的新方法．土壤学报．1995，32(2)：210-219．
[341]常会宁，夏景新．草地放牧制度及评价．国外畜牧学—草原与牧草．1994，4：9-14．
[342]常生华，李广，侯扶江．我国沙尘暴发生日数的空间分布格局．中国沙漠．2006，26(3)：384-388．
[343]陈莉，刘照辉，赵红洋等．运动场草坪践踏强度及其恢复系的研究．草原与草坪．2002，(4)：28-30
[344]陈利顶，傅伯杰．干扰的类型、特征及其生态学意义．生态学报．2000，20(4)：581-586．
[345]陈明．神经网络模型．大连：大连理工大学出版社．1993．
[346]陈明华，周福建，黄炎和．土壤可蚀性因子的研究．水土保持学报．1995，9(1)：19-24．
[347]陈善科，徐平，张学英．阿拉善荒漠生态危机及其治理对策．草原与草坪．2000，(3)：9-11．
[348]陈震，吴俊兰编著．土壤肥料理化性质简易测定法．北京：农业出版社．1980，p63．
[349]陈忠东．放牧干扰对林地及林木生长影响分析与评价．林业科学研究．2003，16(3)：312-318．
[350]陈佐忠，黄德华，张鸿芳．内蒙古锡林河流域羊草草原和大针茅草原地下生物量与降水量关系模型探讨．见：草原生态系统研究(2)．北京：科学出版社．1988．20-26．
[351]程炽民．长芒草草地在封育条件下群落结构和生物量变化的研究．草业科学．1993，10(2)：14-18．
[352]程积民，万惠娥．中国黄土高原植被建设与水土保持．北京：中国林业出版社．2002．
[353]戴其根，周兰胜，陈后庆，张洪程，霍中洋，许柯．践踏强度对不同坪床结构狗牙根地上部生长的影响．扬州大学学报(农业与生命科学版)．2006，27(2)：86-90．
[354]丁飞，张祖兴，蔡阿兴，胡续礼，姜小三，潘剑君．土壤侵蚀强度分级标准中土壤厚度参考指标适用性的探讨．中国农学通报．2006，22(7)：343-346．
[355]董长虹编著．神经网络与应用．北京：国防工业出版社．2005．
[356]董全民，李青云，马玉寿，施建军．耗牛放牧率对小嵩草高寒草甸地上、地下生物量的影响初析．四川草原．2004，2：20-27．
[357]董全民，赵新全，马玉寿，代勇，施建军，王启基．江河源区披碱草和星星草混播草地土壤物理性状对耗牛放牧强度的响应．草业科学．2005，22(6)：65-70．
[358]董全民，赵新全，马玉寿，李芙蓉，来德珍．不同耗牛放牧率下江河源区垂穗披碱草-星星草混播草地第一性生产力及其动态变化．中国草地学报．2006，28(3)：5-15．
[359]董全民，赵新全，马玉寿，李青云，王启基，施建军．耗牛放牧率与小禽草高寒草甸暖季草地地上、地下生物量相关分析．草业科学．2005，22(5)：65-71．
[360]董世魁，江源，黄晓霞．草地放牧适宜度理论及牧场管理策略．资源科学．2002，24(6)：35-41．
[361]董世魁．什么是草原载畜量．国外畜牧学-草原与牧草．1998，(1)：6-11．
[362]杜睿，王庚辰，吕达仁．放牧对草原土壤N_2O产生及微生物的影响．环境科学．2001，22(4)：11-15．
[363]杜玉珍，赵钢，阎景赞．放牧制度对天然草地土壤物理性状及奶牛生产性能的影响．中国土地．2005，27(4)：47-51．
[364]范春梅，廖超英，孙长忠，许喜明，李培玉．放牧对黄上高原丘陵沟壑区林草地土壤特性的影响．西北农业学报．2006，15(1)：24-28．
[365]范锦龙，潘志华，赵举，郑大玮，妥德宝，赵沛义．风蚀强度的空间差异及影响分析．水土保持学报．2003，17(2)：100-136．
[366]冯利华．基于ANN的土壤侵蚀研究．土壤侵蚀与水土保持学报．1999，5(6)：105-109．
[367]冯晓静，高焕文，毛宁，王树东．永定河沙地播草盖沙效果的风洞试验研究．中国水土保持．2006，4：16-17．
[368]符义坤，孙吉雄．草地改良与利用．兰州：甘肃科学技术出版社．1986．57-135．
[369]傅华，王彦荣，吴彩霞，塔拉腾．放牧对阿拉善荒漠草地土壤性状的影响．中国沙漠．2002，22(4)：339-343．
[370]高英志，韩兴国，汪诗平．放牧对草原土壤的影响．生态学报．2004，24(4)：790-797．
[371]关世英，常金宝，贾树海，李绍，良陈有君，王玉芬．草原暗栗钙土退化过程中的土壤性状及其变化规律的研究．中国草地．1997，33：39-43．
[372]郭冬梅，白英，郭炜．表层风蚀土壤粒径分布的分形特征研究．内蒙古农业大学学 报．2005，26(1)：82-86．
[373]郭忠升，邵明安．土壤水分植被承载力数学模型的初步研究．水利学报．2004，10：95-99．
[374]韩国栋．划区轮牧和季节连续放牧绵羊的牧食行为．中国草地．1993．(2)：1-14．
[375]韩永伟，韩建国，张蕴薇，王堃．农牧交错带退耕还草地土壤风蚀影响因子分析．生态环境．2005，14(3)：382-386．
[376]郝高建，赵先贵．甘肃省环县生态环境建设及生态农业发展模式研究．水土保持研究．2004，11(1)：23-26．
[377]郝高建，赵昕，赵先贵．黄土高原生态建设与生态农业发展模式—以甘肃省环县为例．干旱区研究．2004，21(1)：44-48．
[378]郝兴中，常生华．黄土高原农牧交错带草业发展前景浅析—对环县苜蓿草产业发展的分析．草业科学．2002，19(5)：40-42．
[379]贺秀斌，文安邦，张信宝，朱波．农业生态环境评价的土壤侵蚀退耦指标体系．土壤学报．2005，42(5)：852-856．
[380]红梅，韩国栋，赵萌莉，索培芬，潘林瑞．放牧强度对浑善达克沙地土壤物理性质的影响．草业科学．2004，21(12)：108-111．
[381]侯扶江，南志标，肖金玉，常生华．重牧退化草地的植被、土壤及其耦合特征．应用生态学报．2002．13(8)：915-922．
[382]侯扶江，任继周．甘肃马鹿冬季放牧的践踏作用及其对土壤理化性质影响的评价．生态学报．2003，23(3)：486-495．
[383]侯扶江，杨中艺．放牧对草地的作用．生态学报．2006，26(1)：244-264．
[384]侯扶江，常生华，于应文，林慧龙．放牧家畜的践踏作用研究评述．生态学报．2004，24(4)：133-139．
[385]侯扶江，肖金玉，南志标．黄土高原退耕地的生态恢复．应用生态学报．2002，13(8)：923-929．
[386]侯扶江．放牧对牧草光合作用呼吸作用和氮碳吸收与转运的影响．应用生态学报．2001，12(6)：938-933．
[387]胡孟春，王周龙．土壤风蚀的自然-社会复合系统动态过程模拟研究．科学通报．1994，39(12)： 1118-1121．
[388]胡云锋，刘纪远，庄大方，曹红霞，闫慧敏，杨风亭．风蚀土壤剖面~(137)Cs的分布及侵蚀速率的估算．科学通报．2005，50(9)：933-937．
[389]胡云锋，刘纪远，庄大方，杨风亭．土地利用动态与风力侵蚀动态对比研究—以内蒙古自治区为例．地理科学进展．2003，22(6)：541-550．
[390]胡中民，樊江文，钟华平，韩彬．中国草地地下生物量研究进展．生态学杂志．2005，24(9)：1095-1101．
[391]胡自治，孙吉雄，李洋，龙瑞军，杨发林．甘肃天祝主要高山草地的生物且及光能转化率．植物生态学报．1994，18(2)：121-131．
[392]环县生态环境建设领导小组办公室．环县1999年生态环境建设文件汇编．2000，12．
[393]黄富祥，高琼，赵世勇．生态学视角下的草地载畜量概念．草业学报．2000，9(3)：48-57．
[394]黄金杰，李士勇，左兴权．一个基于粗糙集的水土流失防治动态决策系统．中国地质灾害与防治学报．2002，13(3)：67-72．
[395]贾慎修主编．草地学．北京：中国农业出版社．1982．p186-188．
[396]贾树海，王春枝，孙振涛，李绍良，陈有君，靳存旺．放牧强度和时期对内蒙古草原土壤压实效应研究．草地学报．1999，7(3)：217-222．
[397]贾树海，崔学明，李绍良．牧压梯度上土壤物化性质的变化．见：中国科学院内蒙古草原生态系统定位研究站编．草原生态系统研究(第五集)．北京：科学出版社．1996．p12-16．
[398]贾树海，张海涛，李晓安，钱凤魁，王秋兵．放牧强度对草原砂质栗钙土某些物理性质影响的研究．土壤通报．2006，37(4)：821-823．
[399]贾媛媛，郑粉莉，杨勤科．国外水蚀预报模型述评．水士保持通报．2003，3(5)：82-87．
[400]江忠善，郑粉莉，武敏．中国坡面水蚀预报模型研究．泥沙研究．2005，4：1-6．
[401]姜娜，邵明安，雷廷武．水蚀风蚀交错带坡面土壤入渗特性的空间变异及其分形特征．土壤学报．2005，42(6)：904-908．
[402]蒋文兰，张英俊，符义坤，冉繁军．绵羊宿营法防除天然草地灌木杂草研究，Ⅱ绵羊啃食和践踏对植物与土壤物理性状的影响．草业学报．1999，8(增刊)：82-89．
[403]蒋文兰，瓦庆荣，刘兴元．贵州岩溶山区绵羊宿营法改良天然草地综合研究．1．绵羊宿营时间、强度及牧草混播组合的处理效果．草业学报．1996a，5(1)：17-25．
[404]蒋文兰，瓦庆荣，吴明强．贵州岩溶山区绵羊宿营法改良天然草地综合研究．3．改良草地的技术、生态、经济效果研究．草业学报．1996c，5(1)：31-36．
[405]蒋文兰，瓦庆荣，张明忠．贵州岩溶山区绵羊宿营法改良天然草地综合研究．2．改良后草地牧草生产力持久性研究．草业学报．1996b，5(1)：26-30．
[406]敬永方，常生华．环县天然草原退化现状与治理对策．草业科学．2002，19(3)：9-11．
[407]敬永方，张富忠，常生华．黄土高原农牧交错带苜蓿草地固沙效果观察—环县试验报告．草业科学．2003，20(7)：58-59．
[408]瞿王龙，裴世芳，周志刚，张宝林，傅华．放牧与围封对阿拉善荒漠草地土壤有机碳和植被特征的影响．甘肃林业科技．2004，29(2)：4-6．
[409]雷阿林，史衍玺，唐克丽．土壤侵蚀模型实验中的土壤相似性问题．科学通报．1996，41(19)：1801-1804．
[410]李博，雍世鹏，李瑶．中国的草原．北京：科学出版社．1990．
[411]李博．生态学与草地管理．中国草地．1994，1：1-8．
[412]李博．中国北方草地退化及其防治对策．中国农业科学．1997，30(6)：1-9．
[413]李德颖，Warren，F．H．混播草坪上足球运动践踏模拟效果的研究．农业工程学报．1997，(2)：164-168．
[414]李冬杰，杨培岭，王勇，刘洪禄，郝仲勇．土壤水分对草坪草蒸散及生长特性的影响．草地学报．2005，13(3)：308-312．
[415]李建龙，许鹏，孟林，王建华．不同轮牧强度对天山北坡低山带蒿属荒漠秋场土草畜影响研究．草业学报．1993，2(2)：60-65．
[416]李鹏，李占斌，鲁克新．黄土区草木植被根系与土壤垂直侵蚀产沙关系研究．植物生态学报．2006，30(2)：302-306．
[417]李绍良，陈有君，关世英，康师安．土壤退化与草地退化关系的研究．干旱区资源与环境．2002，16(1)：92-95．
[418]李绍良，陈有君．锡林河流域栗钙土及其物理性状与水分动态的研究．中国草地．1999，3：71-76．
[419]李绍良，贾树海，陈有君，康师安，关世英，何婕平．内蒙古草原土壤退化进程及其评价指标的研究．土壤通报．1997，28(6)：241-243．
[420]李胜功，赵哈林，何宗颖，常学礼，原圆芳信，大黑俊哉，根本正之．不同放牧压力下草地微气象的变化与草地荒漠化的发生．生态学报．1999，19(5)：697-704．
[421]李师翁，范小峰．甘肃环县天然草地植被近40年演变的研究．水土保持学报．2003，17(6)：114-117．
[422]李树会，张东为．美国有关放牧对土壤性质影响的研究．水土保持科技情报．2003，17(1)：8-9．
[423]李文建，韩国栋．放牧家畜研究进展．内蒙古畜牧科学．2000，21(3)：24-27．
[424]李香真，陈佐忠．不同放牧率对草原植物与土壤C、N、P含量的影响．草地学报．1998，6(2)：90-98．
[425]李香真，曲秋皓．内蒙高原草原土壤微生物量碳氮特征．土壤学报．2002，39(1)：97-104．
[426]李香真．放牧对暗栗钙土磷的贮量和形态的影响．草业学报．2001，10(2)：28-32．
[427]李晓丽，申向东．结皮土壤的抗风蚀性分析．干旱区资源与环境．2006，20(2)：203-207．
[428]李银鹏，季劲钧．全球陆地生态系统与大气之间碳交换的模拟研究．地理学报．2001，56(4)：379-389．
[429]李银鹏，季劲钧．内蒙古草地生产力资源和载畜量的区域尺度模式评估．自然资源学报，2004，19(4)：610-616．
[430]李英年．高寒草甸牧草产量和草场载畜量模拟研究及对气候变暖的响应．草业学报．2000，9(2)：77-82．
[431]李英年．高寒草甸植物地下生物量与气象条件的关系及周转值分析．中国农业气象．1998，19(1)：36-39．
[432]李永宏，莫文红，杨持．内蒙古主要草原植物群落地上生物量和理论载畜量及其与气候的关系．干旱区资源与环境．1994，8(4)：43-50．
[433]过度放牧对生态环境的影响与控制对策．中国沙漠．2005，25(3)：404-408．
[434]李忠辉，郑大玮，潘志华．农牧交错带缓坡丘陵区土壤风蚀研究—以内蒙古后山地区为例．中国水土保持．2004,6：17-20．
[435]李子忠，黄顶，王忠彦．灌溉制度对老芒麦(Elymus sibiricus)生长的影响．中国农业科学．2005，38(8)：1621-1628．
[436]廖超英，李靖，郑粉莉，刘国彬．国外土壤风蚀预报的研究历史与动向．水土保持研究．2004，11(4)：50-53．
[437]林慧龙，董世魁．高寒地区多年生禾草混播草地种间竞争效应分析．草业学报．2003，12(3)：79-82．
[438]林慧龙，侯扶江．草地农业生态系统中的系统耦合与系统相悖研究动态．生态学报．2004，24(6)：1252-1258．
[439]林慧龙．草地农业：从结构性描述到精确化发展刍议．草业科学．2007，24(6)：9-17．
[440]刘艾，刘德福．我国草地生物量研究概述．内蒙古草业．2005，17(1)：7-11．
[441]刘宝元，张科利，焦菊英．土壤可蚀性及其在侵蚀预报中的应用．自然资源学报．1999，14(4)：345-350．
[442]刘秉正，吴发启．土壤侵蚀．西安：陕西人民出版社．1997．
[443]刘吉峰，李世杰，秦宁生，于守兵．青海湖流域土壤可蚀性K值研究．干旱区地理．2006，29(3)：321-326．
[444]刘建军，浦野忠朗，鞠子茂，及川武久．放牧对草原生态系统地下生产力及生物量的影响．西北植物学报．2005，25(1)：88-93．
[445]刘良梧，周建民，刘多森，等．农牧交错带不同利用方式下草原土壤的变化．土壤．1998，30(5)：225-229．
[446]刘晓民，程国彦，郝建国，范希全．农田留茬覆盖抗风蚀效果浅析．农村牧区机械化．2005,62(1)：10—13．
[447]刘艳萍，荣浩，邢恩德．草原水保生态环境监测整体发展研究．水土保持科技情报．2004，5：40-42．
[448]柳承茂．MATLAB 5.X入门与应用．北京：科学出版社．1999．
[449]龙利群，李新荣．微生物结皮对两种一年生植物种子萌发和出苗的影响．中国沙漠．2002，22(6)：581-585．
[450]鲁如坤．土壤农业化学分析方法．北京：中国农业科技出版社．1999．p：638．
[451]罗俊强，韩烈保，陈宝书．草坪地下生物量与坪用性状的关系．北京林业大学学报．2000，22(2)：77-80．
[452]马春梅，杨静，卫智军．放牧绵羊牧食习性的比较研究．内蒙古草业．2000，(2)：53-57．
[453]马东涛，祁龙，邓晓峰．甘肃环县东山黄土泥流综合治理．山地学报．2000，18(3)：217-220．
[454]马生发，胡景平．环县北部沙漠化现状及防治对策．甘肃农业科技．2002，5：8-9．
[455]马文红，韩梅，林鑫，任艳林，王志恒，方精云．内蒙古温带草地植被的碳储量．干旱区资源与环 境．2006，20(3)：192-195．
[456]马永年．环县农业生态环境建设中存在的问题及对策．甘肃农业科技．2004，2：3-5．
[457]迈克·费斯特．土壤生物结皮在干旱半干旱地区退化生态系统恢复中的作用．中国水土保持科学．2005，3(4)：42-47．
[458]毛留喜，孙艳玲，延晓冬．陆地生态系统碳循环模型研究概述．应用生态学报．2006，17(11)：2189-2195．
[459]门明新，赵同科，彭正萍，宇振荣．基于土壤粒径分布模型的河北省土壤可蚀性研究．中国农业科学．2004，37(11)：1647-1653．
[460]孟祥亮，严平，宋阳，杨秀春，吴晓．风蚀容忍量研究进展及其若干问题的探讨．中国沙漠．2005，25(3)：315-319．
[461]内蒙古农牧学院．草原管理学．北京：中国农业出版社．1981，p63．
[462]内蒙古农牧学院主编．畜牧学．北京：农业出版社，1981年，p59，162，
[463]倪九派，谢春燕，魏朝富，谢德体．土壤侵蚀预测建模研究进展．中国水土保持科学．2005，3(2)：66-71．
[464]潘锋．我国土壤家底有多“厚”? 《科学时报》2005．6．27．
[465]裴海昆．不同放牧强度下土壤有机质特性变化的研究．青海畜牧兽医杂志．2004b，34(4)：1-3．
[466]裴海昆．不同放牧强度对土壤养分及质地的影响．青海大学学报(自然科学版)2004a，22(4)：29-31．
[467]彭坷珊．中国土壤侵蚀影响因素及其危害分析．首都师范大学学报(自然科学版)．2000，21(2)：88-94．
[468]彭棋，王宁．不同放牧制度对草地植被的影响．农业科学研究．2005，26(1)：27-30．
[469]蒲小鹏，徐长林，刘晓静．放牧利用对金露梅灌丛土壤理化性质的影响．甘肃农业大学学报．2004，39(1)：39-41．
[470]朴世龙，方精云，贺金生，肖玉．中国草地植被生物量及其空间分布格局．植物生态学报．2004，25(4)：491-498．
[471]齐矗华，甘枝茂．黄土高原侵蚀地貌与水土流失关系研究．西安：陕西教育出版社．1991．p12-89．
[472]钱正安，蔡英，刘景涛等．中国北方沙尘暴研究的若干进展．干旱区资源与环境．2004，18(1)：1-8．
[473]任继周，胡自治，张自和，侯扶江，陈全功．中国草业生态经济区初探．草业学报．1999，8(专辑)：12-22．
[474]任继周，郭博，李逸民，李琪，雍际炳．高山草原生产性能的初步探讨．甘肃农业大学科学研究论文汇编．1959，4：：37-48．
[475]任继周，胡自治，牟新待，张普金．草原的综合顺序分类及其草原发生的意义．中国草地．1980，(1)：12-24．
[476]任继周，金巨和．牦牛群放牧习性的观察研究．中国畜牧兽医杂志．1956(2)：58-62．
[477]任继周，李逸民，郭博，李琪．藏羊群自由放牧与分区轮牧的观察研究．中国畜牧兽医杂志．1954(4)：143-157．
[478]任继周，王钦．甘肃天祝永丰滩高山草原更新措施的研究简报．甘肃农业大学学报．1959，4：11-20．
[479]任继周．草地农业生态学．北京：中国农业出版社．1995．p51-84．
[480]任继周．草原地下生物量的启示．草业科学．2006，23(6)：91．
[481]任继周．天祝高山草原早春灌溉问题的探讨(1959)．《任继周文集》第二卷．北京：中国农业出版社，2005．
[482]任继周编著．关于高山草原的调查研究．南京：畜牧兽医图书出版社出版．1957年7月．
[483]任继周编著．草原的培育和利用．兰州：甘肃人民出版社出版．1962年7月．
[484]任继周主编．草地农业生态系统通论．合肥：安徽教育出版社．2004
[485]任继周主编．草业科学研究方法．北京：中国农业出版社．1989．p4．
[486]任继周主编．草原调查与规划．北京：农业出版社．1985．p110-116．
[487]任继周主编．草原学(高等农业学校教学参考书)．北京：农业出版社．1959．
[488]任继周主编．草地农业生态系统通论．合肥：安徽教育出版社．2004．
[489]戎郁萍，韩建国，王培，毛培胜．放牧强度对草地土壤理化性质的影响．中国草地．2001，23(4)：41-46．
[490]尚占环，姚爱兴．国内放牧管理措施的综述．宁夏农林科技．2004，2：32-35．
[491]邵月红，潘剑君，许信旺，米高奇．浅谈土壤有机碳密度及储量的估算方法．土壤通报．2006，37(5)：1007-1011．
[492]宋炳煜．几个主要地面因子对草原群落蒸发蒸腾的影响．植物生态学报．1996，20(6)：485-493．
[493]宋桂龙，韩烈保，周陆波．电动蛙式草坪践踏器．农业机械学报．2006，37(5)：168-170．
[494]宋桂龙，徐泽荣．运动场草坪耐践踏性研究进展．四川草原，2004，(8)：6-9．
[495]宋阳，刘连友，严平，曹彤．土壤可蚀性研究述评．干旱区地理．2006，29(1)：124-131．
[496]宋颖．土壤侵蚀模型研究进展及发展方向．山西水利科技．2006，161(3)：39-41．
[497]苏永中，赵哈林，张铜会，崔建恒．不同强度放牧后自然恢复的沙质草地土壤性状特征．中国沙漠．2002，22(4)：333-338．
[498]孙吉雄．草坪学．北京：中国农业出版社．1996．p1-17．
[499]孙力安，梁一民．草地地下生物量研究综述．国外畜牧学：草原与牧草．1993，1：6-14．
[500]孙力安，刘国彬，梁一民．不同直径土钻测定草地地下生物量方法探讨．中国草地．1994，2：32-35．
[501]滕星，王德利，张宝田．羊草(Leymus chinensis)草地雨天放牧与非雨天放牧的绵羊采食特征．生态学报．2006，26(3)：762-767．
[502]田志珍，常生华，肖金玉，侯扶江，南志标．滩羊体重对放牧强度的短期效应．家畜生态．2004，25(2)：26-31．
[503]汪诗平．放牧绵羊行为生态学研究，Ⅱ不同放牧率对放牧绵羊牧食行为的影响．草业学报．1997，6(1)：10-17．
[504]王长庭，王启基，沈振西，彭红春，李海英．模拟降水对高寒草甸群落影响的初步研究．草业学报．2003，12(2)：25-29．
[505]王尔大，Wyatte Harman，郑大玮，常欣，程序．旱作农区轮作和留茬处理方式对风蚀的影响—应用EPIC模型进行模拟和分析的武川案例．中国农业科学．2002，35(11)：1330-1336．
[506]王关禄，张治国等编著．土壤知识与土壤普查技术．北京：水利电力出版社．1983．p：1-42，295-310．
[507]王国杰，汪诗平，郝彦宾，蔡学彩．水分梯度上放牧对内蒙古主要草原群落功能群多样性与生产力关系的影响．生态学报．2005，25(7)：1649-1656．
[508]王礼先，周金星．关于荒漠化、沙漠化、风沙化和沙化的概念．科技术语研究．2000，4(2)：31．
[509]王利兵，胡小龙，余伟在，李钢铁，郭建英．沙粒粒径组成的空间异质性及其与灌丛大小和上壤风蚀相关性分析．干旱区地理．2006，29(5)：687-693．
[510]王明玖，马长升．两种方法估算草地载畜量的研究．中国草地．1994，(5)：19-22．
[511]王仁忠．放牧干扰对松嫩平原羊草草地的影响．东北师大学报(自然科学版)．1996，(4)：77-82．
[512]王绍强，周成虎．中国陆地土壤有机碳库的估算．地理研究．1999，18(4)：349-356．
[513]王淑强，胡直友，李兆方．不同放牧强度对红三叶、黑麦草草地植被和土壤养分的影响．自然资源学报．1996，11(3)：280-287．
[514]王思远，王光谦，陈志祥．黄河流域土地利用与土壤侵蚀的耦合关系．自然灾害学报．2005，14(1)：32-37．
[515]王涛，吴薇，赵哈林，董治宝，薛娴．沙漠化过程中生物量损失的初步评估．中国沙漠．2005，25(4)：453-456．
[516]王万忠，焦菊英．中国的土壤侵蚀因子定量评价研究．水土保持通报．1996，16(5)：1-20．
[517]王小丹，钟祥浩，范建容．西藏水土流失敏感性评价及其空间分异规律．地理学报．2004，59(2)：183-188．
[518]王效科，欧阳志云，肖寒，苗鸿，傅伯杰．中国水土流失敏感性分布规律及其区划研究．生态学报．2001，21(1)：14-19．
[519]王雪芹，张元明，张伟民，韩致文．古尔班通古特沙漠生物结皮对地表风蚀作用影响的风洞实验．冰川冻土．2004，26(5)：632-638．
[520]王艳芬，陈佐忠，Larry，T．Tieszen．人类活动对锡林郭勒地区主要草原土壤有机碳分布的影响．植物生态学报．1998，22(6)：545-551．
[521]王艳芬，汪诗平．不同放牧率对内蒙古典型草原地下生物量的影响．草地学报．1999，7(3)：198-205．
[522]王跃思，胡玉琼，纪宝明等．放牧对内蒙古草原温室气体排放的影响．中国环境科学．2002，22(6)：490-494．
[523]王跃思，纪宝明，黄耀等．农垦与放牧对内蒙古草原N_2O、CO_2排放和CH_4吸收的影响．环境科学，2001，22(6)：7-13．
[524]王占礼，黄新会，牛振华．国内主要流域侵蚀产沙模型评述．水土保持研究．2004，11(4)：28-33．
[525]王兆印，王光谦，李昌志，王费新．植被—侵蚀动力学的初步探索和应用．中国科学(D辑)．2003，33(10)：1013-1023
[526]魏翔，李占斌．土壤侵蚀对生态系统的影响．水土保持研究．2006，13(1)：245-264．
[527]吴发启，赵晓光，刘秉正，贾锐鱼．地表糙度的量测方法及对坡面径流和侵蚀的影响．西北林学院学报．1998，13(2)：15-19．
[528]吴楠，梁少民，王红玲．动物践踏干扰对生物结皮中微生物生态分布的影响．干旱区研究．2006，23(1)：50-55．
[529]夏景新．载畜率调控的理论与牧场管理实践．中国草地．1995，1：46-54．
[530]徐宪立，马克明，傅伯杰，刘宪春，黄勇，祁建．植被与水土流失关系研究进展．生态学报．2006，26(9)：3137-3143．
[531]许鹏主编．草地资源调查规划学．北京：中国农业出版社．2000，p67-75．
[532]许志信，白飞，曲永全．草原植被利用强度对水土流失影响的研究．内蒙古草业．2000，2：1-7．
[533]许志信，王俊国，赵明旭．干草原植被利用强度对水土流失影响的研究．内蒙古草业．2001a，2：1-6．
[534]许志信，张晓明，白飞，昭和斯图．草甸草原植被利用强度对水土流失影响的研究．内蒙古农业大学学报．2001b，22(-)：68-73．
[535]许志信，赵萌莉．过度放牧对草原土壤侵蚀的影响．中国草地．2001，23(6)：59-63．
[536]许志信，赵萌莉．草原植被与水土流失．内蒙古草业．2000，1：1-6．
[537]许志信．控制载畜量是维持草地生态平衡的关键．草业科学．1990，7(5)：1-10．
[538]许中旗，李文华，阂庆文，敖其尔，王英舜，韩喜，何旭生，贺俊杰．典型草原抗风蚀能力的实验研究．环境科学．2005，26(5)：164-168．
[539]鄢燕，张建国，张锦华，范建容，李辉霞．西藏那曲地区高寒草地地下生物量．生态学报．2005，25(11)：2818-2813．
[540]杨理，侯向阳．以草定畜的若干理论问题研究．中国农学通报．2005，21(3)：346-349．
[541]杨培岭，罗远培，石元春．用粒径的重量分布表征的土壤分形特征．科学通报．1993，38(20)：1896-1899．
[542]杨萍，胡续礼，姜小三，何旭东，潘剑君．小流域尺度土壤可蚀性(K值)的变异及不同采样密度对其估值精度的影响．水土保持通报．2006，26(6)：35-39．
[543]杨文治．黄土高原土壤水分研究．北京：科学出版社．2000．
[544]杨小红，董云社，齐玉春等．草地生态系统土壤氮转化过程研究进展．中国草地．2004，26(2)：54-62．
[545]杨秀春，严平，刘连友．土壤风蚀研究进展与评述．干旱地区农业研究．2003，21(4)：147-153．
[546]杨智明，王琴，王秀娟．放牧强度对草地牧草物候期生活力和土壤含水量的影响．农业科学研究．2005，26(3)：1-3．
[547]杨智明，杨刚，纪庆文，王海军．干筛法和水洗法在测定地下生物量中的对比分析．宁夏农学院学报．2004，25(2)：99-100．
[548]姚爱兴，王培，夏景新，樊奋成．不同放牧强度下奶牛对多年生黑麦草／白三叶草地土壤特性的影响．草地学报．1995，3(3)：181-189．
[549]叶其孝．大学生数学建模竞赛辅导教材．长沙：湖南教育出版社．1993．p49-69．
[550]移小勇，赵哈林，张铜会，李玉强，刘新平，卓鸿．挟沙风对土壤风蚀的影响研究．水土保持学报．2005，19(3)：58-61．
[551]俞斌华，侯扶江，林慧龙．牧草种群生长对家畜践踏的短期响应．草业学报．2005，14(4)：119-124．
[552]宇万太，于永强．植物地下生物量研究进展．应用生态学报．2001，12(6)：927-932．
[553]玉辉，何兴元，周广胜．放牧强度对羊草草原的影响．草地学报．2002，10(1)：45-49．
[554]袁建平．土壤侵蚀强度分级标准适用性初探．水土保持通报．1999，19(6)：54-57．
[555]袁庆华，蒋文兰．羊群宿营对蛴螬控制及草地恢复的影响．中国草地．1995，2：15-19．
[556]袁庆华．高强度放牧对草地蛴螬种群数量的影响．草业学报．1995，4(1)：30-35．
[557]张春来，邹学勇，董光荣，刘玉璋．植被对土壤风蚀影响的风洞实验研究．水土保持学报．2003，17(3)：31-33．
[558]张德二．我国历史时期以来降尘的天气气候学初步分析．中国科学．1984，24(3)：278-288．
[559]张东秋，石培礼，张宪洲．土壤呼吸主要影响因素的研究进展．地球科学进展，2005，20(7)：778-785．
[560]张华，李锋瑞，伏乾科，吕子君．沙质草地植被防风抗蚀生态效应的野外观测研究．环境科学．2004，25(2)：119-124．
[561]张科利，蔡永明．土壤可蚀性动态变化规律研究．地理学报．2001，56(6)：673-681．
[562]张娜，梁一民．黄土丘陵区两类天然草地群落地下部生长及其与土壤水分关系的比较研究．西北植物学报．1999，19(4)：699-706．
[563]张铜会，赵哈林，常学礼，白户康人，大黑俊哉．灌水对沙地草场几种植物生长的影响．中国沙漠．1999，19(增刊)：23-25．
[564]张铜会，赵哈林，大黑俊哉．沙质草地连续放牧后某些上壤性质的变化．中国草地．2003，25(1)：9-12．
[565]张伟华，关世英，李跃进．不同牧压强度对草原土壤水分、养分及其地上生物量的影响．干旱区资源与环境．2000，14(4)：61-64．
[567]张学雷，龚子同．人为诱导下中国的土壤退化问題．生态环境．2003，12(3)：317-321．
[568]张岩，袁建平，刘宝元．土壤侵蚀预报模型中的植被覆盖与管理因子研究进展．应用生态学报．2002，13(8)：1033-1036．
[569]张燕，张洪，彭补拙，杨浩．不同土地利用方式下农地土壤侵蚀与养分流失．水土保持通报．2003，23(1)：23-31．
[570]张英杰，宋豫秦．论我国半干旱草原地区沙漠化防治战略的转型．中国沙漠．2004，24(1)：87-91．
[571]张英俊，蒋文兰，符义坤，樊晓东．绵羊宿营法防除天然草地灌木杂草研究，Ⅰ回顾与进展．草业学报．1999，8(专辑)：76-81．
[572]张英俊．绵羊宿营法清除天然草地灌木无毛丑柳的效果和机理研究．甘肃农业大学博士论文．1999．
[573]张英俊．绵羊宿营法清除天然植被对土壤和植物的影响．草地学报．2002，10(4)：251-257．
[574]张玉斌，郑粉莉，贾媛媛．WEPP模型概述．水土保持研究．2004，11(4)：146-149．
[575]张蕴薇，韩建国，李志强．放牧强度对土壤物理性质的影响．草地学报．2002，10(1)：74-78．
[576]张蕴薇，韩建国，杨富裕．华北农牧交错带地区放牧强度对草地土壤氮营养的影响．四川草原．2005，1：7-9．
[577]张治国，曲继宗，卫元太，崔峰．土壤侵蚀模数控制率计算方法探讨．山西水土保持科技．2004，1：21-22．
[578]张自和．草原退化的后果及深层原因探讨．草业科学．1995，12(6)：1-5．
[579]赵刚，许志信，李德新．反刍家畜牧食行为综述．内蒙古农业大学学报．2000，21(2)：109-116．
[580]赵哈林，根本正之，大黑俊哉，李胜功．内蒙古科尔沁沙地放牧草地的沙漠化机理研究．中国草地．1997，3：15-23．
[581]赵焕勋，王学东．内蒙古土壤侵蚀灾害研究．干旱区资源与环境．1994，8(4)：35-42．
[582]赵吉．不同放牧率对冷蒿小禾草草原土壤微生物数量和生物量的影响．草地学报．1999，7(3)：223-227．
[583]赵立祥．草原荒漠化的物理过程．草业科学．2004，21(11)：7-10．
[584]赵仁镕，余松烈编著．田间试验方法．北京：农业出版社．1984．
[585]赵西宁，吴普特，冯浩，王万忠，吴发启．坡面土壤侵蚀产沙的神经网络模拟．土壤学报．2006，43(2)：324-327．
[586]赵友．风蚀坑对草原的破坏及治理．当代畜牧．1999，5：41．
[587]郑粉莉，杨勤科，王占礼．水蚀预报模型研究．水土保持研究．2004，11(4)：13-24．
[588]郑淑华，赵萌莉，韩国栋，红梅，贵满全，乌力吉．不同放牧压力下典型草原土壤物理性质与植被关系的研究．干旱区资源与环境．2005，19(7)：199-203．
[589]中国科学院南京土壤研究所．土壤理化分析．上海：上海科学技术出版社．1983．p：593．
[590]中国土壤学会编．土壤农业化学分析方法．北京：中国农业出版社．2000，p146-195、272-276．
[591]中华人民共和国农业部畜牧兽医司，中国农业科学院草原研究所，中国科学院自然资源综合考察委员会编．中国草地资源数据．北京：中国农业科技出版社．1994．
[592]周保鑫，孙吉雄．草坪践踏器的原理及其研制．甘肃农业大学学报．1994，29(1)：93-95．
[593]周道玮，钟秀丽．干扰生态理论的基本概念和扰动生态学理论框架，东北师大学报．1996，1：90-96
[594]周广胜，王玉辉，蒋延玲，杨利民．陆地生态系统类型转变与碳循环．植物生态学报．2002，26(2)：250-254．
[595]周禾，牛建忠．我国草坪科学研究与发展．中国农学通报．2001．17(5)：41-43．
[596]周继成，周青山，韩飘扬．人工神经网络—第六代计算机的实现．北京：科学普及出版社．1993．P47-51．
[597]朱连奇，许叔明，陈沛云．山区土地利用／覆被变化对土壤侵蚀的影响．地理研究．2003，22(4)：432-438．
[598]朱显漠．径河流域土壤侵蚀现象及其演变．土壤学报．1954，2(4)：209-222．
[599]朱震达，陈广庭著．中国土地沙质荒漠化．北京：科学出版社．1994．
[600]朱震达，刘恕．中国北方地区的沙漠化过程及其治理区划．北京：中国林业出版社．1981．p19-22．
[601]朱震达．全球变化和荒漠化-地学前缘．北京：中国科学技术出版社．1997．p213-219．