植物篱对紫色土水土特性的效应及作用机理
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摘要
紫色土是我国亚热带地区的一种重要的旱作土壤,集中分布在四川盆地。目前,紫色土坡耕地的水土流失极为严重,亟需进行有效的防治。植物篱不仅能控制水土流失,还可以改善土壤养分状况、调节农田小气候等,具有良好的生态、经济和社会效益,是治理紫色土坡耕地水土流失的一种重要的农艺生物措施。本研究从植物篱的地上部分到地下部分,群体到个体,宏观到微观,较为全面地分析植物篱对紫色土水土特性的影响效应及影响机理,国内外不多见。研究中,以新银合欢(Leucaena leucocephala)和香根草(Vetiveria zizanioides)构建植物篱,采用了标准径流小区(10°、15°)试验、室内土壤理化性质和微生物类群分析,研究了植物篱对紫色土坡耕地水土流失量、微地形、表土机械组成、表土养分分布、表土微生物的影响；以草本植物(紫花苜蓿(Medicago sativa)、香根草(V. zizanioides)、狗牙根(Cynodon dactylon)、百喜草(Paspalum natatu))为目标物种,采用了WinRHIZO根系扫描、土壤理化性质分析试验、直剪试验和抗冲试验,分析了草本植物根系对紫色土表土容重、孔隙度、养分分布、抗剪性能、抗冲性能的影响。主要研究结果如下：
(1)10°,15°坡耕地上,新银合欢植物篱和香根草植物篱均表现出一定的水土保持效应。据2010年和2011年径流小区的水土流失监测数据知,植物篱对泥沙的控制效应优于对径流的控制效应；同坡度时,香根草植物篱对径流泥沙的拦截效应优于新银合欢植物篱；定植时间较长时,植物篱的减流减沙效益较好,尤其表现在固土减沙方面；坡度对径流泥沙的影响显著于植物篱对径流泥沙的影响。定植2年后,植物篱改变坡耕地微地形的效应开始显现,且15°坡耕地比10°坡耕地、香根草植物篱比新银合欢植物篱、底行植物篱比中行、顶行植物篱稍明显。
(2)10°,15°坡耕地上,新银合欢植物篱和香根草植物篱小区表层(0-20cm)土壤机械组成和养分空间分布均发生变化。2010年,土壤机械组成和养分空间分布呈现一定规律：土壤细颗粒富集在坡脚、坡腰；养分富集在坡脚,坡顶的流失量减少；部分养分富集在篱带前。有机质在坡脚的富集最为明显,其次是全氮、总磷、有效磷和速效钾。有机质、全氮、碱解氮、有效磷、全钾和速效钾在篱带前均发生富集。10°坡地,香根草植物篱小区的细颗粒增量大于新银合欢植物篱小区,在拦截效果上,两种植物篱均表现为：砂粒>粉粒>粘粒。对全氮、有效磷、全钾的影响,新银合欢植物篱>香根草植物篱；对有机质、碱解氮、全磷、速效钾的影响,香根草植物篱>新银合欢植物篱。总体上,植物篱对全效养分的影响大于速效养分,香根草对土壤颗粒和养分分布的影响大于新银合欢。
2011年,总体上,土壤有机质、全氮、碱解氮、总磷、有效磷、全钾均减少,尤其是碱解氮和有效磷大幅度减少,速效钾则大量增加；植物篱对速效养分的影响大于全效养分。在坡面分布上,仅总磷的分布规律与2010年的类似,由坡顶向坡脚递增,其余养分的坡面分布规律与2010的差异较大。2011年的土壤养分数据及坡面分布规律极大异常,需要长期监测以探寻原因和正确揭示植物篱对土壤养分的影响规律及机制。
(3)10°,15°坡耕地上,新银合欢植物篱和香根草植物篱均能显著提高土壤中细菌、真菌和放线菌数量及微生物量碳氮含量、有机碳含量,其中土壤细菌数量、土壤微生物量碳氮含量较对照小区的增幅均在50%以上。总体上,香根草植物篱对上述各指标的影响大于新银合欢植物篱,尤其是对土壤微生物量氮含量的影响,10°坡耕地上香根草植物篱小区的增幅较新银合欢植物篱小区高30%余。坡度对上述微生物指标均有显著影响,10°坡较之15°坡更有利于上述指标的提高。各小区的上述微生物指标在坡面上呈现一个与2010年土壤养分相似的分布规律：由坡顶向坡脚递增,篱带前发生富集。其中,土壤真菌、土壤微生物量碳、土壤有机碳的富集较明显。各微生物指标均与土壤有机质、全氮、速效钾含量显著正相关,尤其是土壤有机质碳含量与土壤有机质含量,土壤有机碳含量与土壤全氮含量,土壤真菌数量与土壤速效钾含量。
(4)同一立地条件下,定植1年的紫花苜蓿、香根草、狗牙根、百喜草对紫色土表土(0-30cm)容重、孔隙度影响较显著且呈现一定规律性,对表土(0-20cm)机械组成几乎无影响,对表土(0-20cm)养分影响较弱。较对照小区,4个草本区表土容重降低,总孔隙度提高,土壤通透性得到改善,其中紫花苜蓿区最为明显。草本区,表土容重表现为：0-10cm土层<10-20cm土层<20-30cm土层,与根长密度RLD (root length density)的垂直分布相反；总孔隙度表现为：0-10cm土层>10-20cm土层>20-30cm土层,与RLD的垂直分布一致。相关分析知,L≤0.5mm和L>5mm径级的根系对降低表土容重,改善土壤孔隙性贡献最大；全氮、碱解氮与各径级根长密度RLD显著(极显著)相关,其他养分与各径级根长密度RLD相关性则不显著。
(5)同一立地条件下定植1年后,紫花苜蓿、香根草、狗牙根、百喜草的根系均能显著增强表土层(0-10,10-20,20-30cm)根-土复合体的抗剪性能。其中,香根草的增强效果最为显著：100～400kPa竖向荷载下,抗剪强度较对照提高117%～195%,紫花苜蓿、百喜草和狗牙根的提高幅度分别为：18%～125%,18%～186%,21%～68%。对照小区、香根草区、狗牙根区、百喜草区的抗剪强度指标(内摩擦角φ和粘聚力c)表现为：土层越深,值越小；紫花苜蓿区的趋势则相反。较之土壤含水率,根系对复合体抗剪性能的影响更显著。根本身的抗剪性能是影响复合体抗剪性能的关键,同径级百喜草根的抗剪性能优于紫花苜蓿根。各径级RLD与根干重显著或极显著相关,但各径级RLD与内摩擦角φ、粘聚力c,根干重与内摩擦角φ、粘聚力c均无显著相关。
(6)同一立地条件定植1年后,紫花苜蓿、香根草、狗牙根、百喜草的根系均能显著增强表土层(0-30cm)根-土复合体的抗冲性能,尤其是香根草和百喜草。冲刷试验的各特征时刻(1,2,3,4,7,10min),草本区的径流含沙量均小于对照小区,且表现为：香根草区<百喜草区<狗牙根区<紫花苜蓿区。紫花苜蓿区和香根草区的径流含沙量变化过程用二次函数拟合较好,对照区和百喜草区的用幂函数拟合较好。各试验小区的土壤抗冲指数ANS与冲刷时间t能较好地用用二次多项式进行拟合,香根草区和百喜草区的拟合效果最好,狗牙根区的拟合效果稍差。这4种根系对表土的抗冲性能均有很好的增强效果,其中香根草的增强效果最好,强化百分率高达277.53%,其次是百喜草。相关分析知：根长密度RLD与抗冲指数ANS显著相关,根表面积与抗冲指数ANS极显著相关。
紫色土区缓坡地,新银合欢植物篱和香根草植物篱对表土理化性质、微生物学性质、力学性质等产生有利影响,进而提高了土壤肥力、抗侵蚀能力和潜在生产力,作为一种生态型的坡耕地治理措施,值得推广。在定植的初期,香根草植物篱对上述各方面的影响效果较显著,这是其茂密茎叶、密实篱笆的机械拦截,较多易分解枯落物的腐解,发达根系的网络固持、加筋作用等共同产生的效应。紫花苜蓿固持土壤的能力较香根草弱,但其根系较香根草深、发达,对表土理化性质亦有较好的改善效果,且是一种良好的牧草,作为植物篱品种很适合在牧区的坡耕地治理中采用。百喜草根系形态小且在土层中分布浅,却具有仅次于香根草的固土抗冲效果,很适合在浅层滑坡地带采用。植物篱对紫色土坡地水土特性的影响是一个复杂的过程,其机理亦非常复杂,需要进行长期、全方位的监测与多学科、深入的研究。
Purple soil mainly distributes in the Sichuan Basin of China. Purple soil layer is shallow, loose, and extremely prone to soil erosion. Soil erosion in sloping cropland of purple soil is very serious. Hedgerow could control soil erosion, improve soil nutrient status, and regulate farmland microclimate. Hedgerow has good ecological, economic and social benefits. It is an important agronomic and biological measure to prevent soil erosion. Herbal hedgerow grows fast and has dense root system. The plant of herbal hedgerow is simple, and the cost is low, and it is able to conserve soil and protect slope in a relatively short time after the plant. Hence, herbal hedgerow is very suitable to be applied in hill areas for soil and water conservation. In this study, the soil conservation mechanisms of hedgerow were studied from both the underground system and the above-ground system of the hedgerow. The above-ground part was researched by growing Leucaena leucocephala and Vetiveria zizanioides hedgerows in standard runoff plots (10°,15°) and by analyzing soil physical, chemical and microbiological characteristics. The underground part was researched by growing grasses, Medicago sativa, V. zizanioides, Cynodon dactylon and Paspalum natatu. Root characteristics of herbs were analyzed by WinRHIZO root scanning system, and soil physical and chemical characteristics were analyzed, and anti-shear ability and anti-scourability were also measured. The effects of hedgerow on soil erosion, slope micromorphology, surface soil particle composition, nutrients distribution and microbial populations in purple soil sloping cropland were analyzed quantitatively. The main results are as follows:
(1) In sloping cropland of10°,15°, both L. leucocephala and V. zizanioides hedgerows showed soil and water conservation effects. According to the data of runoff plots monitored in2010and2011, the two kinds of hedgerows had better effect on sand sediment than on surface runoff. At the same declivity, V. zizanioides hedgerow demonstrated better ability than L. leucocephala hedgerow in controlling soil erosion.1year after the plant of hedgerow, declivity showed more obvious effect on soil erosion than hedges. But this phenomenon changed in the next year. The micromorphology of sloping cropland changed in hedgerow plots2years after the plant, represented as sand deposition before the hedgerows, slope declivity decreased between two hedgerows lines, and ridges formed under hedgerow lines. The hedgerow of V. zizanioides changed the micromorphology more significantly than that of L. leucocephala.
(2) In sloping cropland of10°,15°, the mechanical constitution and nutrient distribution of plots changed after the plant of hedgerow. In2010, small soil particle (silt and clay) accumulated at the foot and in the middle of the slope. The nutrient loss on the top of the slope reduced, and nutrients enriched at the foot of the slope, among which the enrichment of soil organic matter were most distinguishing, and the next were total nitrogen, total phosphorus, available phosphorus and available potassium, respectively. Total nitrogen did not enriched before hedgerows. The amount of total potassium increased in all plots. In10°sloping cropland, small soil particles increased more significantly under V. zizanioides hedgerow than that under L. leucocephala hedgerow. The intercept effects of these two kinds of hedgerows to soil particles were sand> silt> clay. L. leucocephala hedgerow affected total nitrogen, available phosphorus and total potassium more significantly than V. zizanioides hedgerow did, while V. zizanioides hedgerow affected soil organic matters, available nitrogen, total phosphorus and available potassium more significantly. In general, both kinds of hedgerows showed more significant effect on the total nutrients of soil than on available nutrients and V. zizanioides affected the redistribution of soil particles and nutrients more significantly than L. leucocephala did.
In2011, the effect of hedgerows on soil nutrient became more complex. On the whole, soil organic matter, total nitrogen and phosphorus, available nitrogen and phosphorus, total potassium reduced. But available potassium increased greatly. Hedgerows'effect on soil available nutrient was greater than on the total nutrient. In the slope distribution, only total phosphorus's distribution was similar as that in2010. Overall, soil nutrient contents and their slope distribution in2011were abnormal and long-term monitor is needed to explore the effect of hedgerows on soil nutrient characteristics.
(3) In sloping cropland of10°,15°, V. zizanioides and L. leucocephala both improved the content of bacteria, fungi, actinomyces, microbiological carbon, microbiological nitrogen, and organic matters in soil. The content of bacteria, microbiological carbon and microbiological nitrogen increased more than50%. In general, V. zizanioides improved soil microbiological indicators mentioned above more significantly than L. leucocephala did. Especially the content of microbiological nitrogen was30%higher in V. zizanioides plots than that in L. leucocephala plots at the same declivity. The slope declivity also affected the soil microbiological indicators mentioned above significantly. These indicators increased as the slope got more moderate. These soil microbiological indicators showed a similar distribution tendency as soil nutrient in2010:increasing progressively from the top to the bottom of slopes and enriching before hedgerow lines. The content of microbes demonstrated remarkable positive relation with soil organic matters, total nitrogen and available potassium.
(4) Under the same site, M. sativa, V. zizanioides, C. dactylon and P. notatum planted for1year had a significant effect on bulk density, porosity of surface soil layer (0-30cm), but they had almost no influence on soil particle composition and showed small influence on nutrients content of surface soil layer (0-20cm). Compared with control plots, soil bulk density decreased and total porosity increased in the4herbal plots. So soil aeration and water permeability had improved in herbal plots, especially in M. sativa Plot. In herbal plots, surface soil bulk density showed the opposite order of RLD (root length density) as0-10cm layer<10-20cm layer<20-30cm layer, but total porosity had the same order of RLD, shown as0-10cm layer>10-20cm layer>20-30cm layer. According to Spearman correlation analysis, roots of L≤0.5mm and L>5mm showed significant contributions to physical indicators mentioned above. Total nitrogen and available nitrogen showed significant correlations with RLD of all diameters, but other nutrients almost showed no correlation with RLD.
(5) Under the same site, after1year's plant, the root systems of M. sativa, V. zizanioides, C. dactylon and P. notatum could significantly strengthen anti-shear ability of root-soil complex in the surface soil layer (0-10,10-20,20-30cm), respectively. Among them the effect of V. zizanioides was the most significant:at100-400kPa vertical load, the anti-shear strength was improved117%-195%as compared with control, and the increase percentages of M. sativa, P. notatum and C. dactylon were18%-125%,18%-186%,21%-68%, respectively. In the plots of control, V. zizanioides, C. dactylon and P. notatum, anti-shear strength parameters (internal friction angle ψ, cohesionc) showed as:the soil layer got deeper, the value got smaller. The tendency in M. sativa plot was on the opposite. The root system showed stronger effect on the anti-shear ability of complex than on soil water content. The anti-shear ability of root was the key factor that improved root-soil complex anti-shear ability. The root of P. notatum had stronger anti-shear strength than that of M. sativa of the same diameter. Various diameters of RLD showed strong correlation with RDW (dry wet of root). But RLD showed no relation with φ andc, so as RDWto φ andc.
(6) Under the same site,1year after the plant, root systems of M. sativa, V. zizanioides, C. dactylon and P. notatum significantly strengthened the anti-scourability of root-soil complex from the surface soil layer (0-30cm), respectively. At different time points of scour experiment, the sand contents of runoff in the herb plots were lower than that of control plot, and showed the order as V. zizanioides In gentle slope of purple soil region, L. leucocephala and V. zizanioides hedgerows had beneficial effects on surface soil physical and chemical properties, microbial properties, and mechanical properties. As an ecological management measure to sloping cropland, hedgerow could be widely used. In the initial stage, V. zizanioides had a significant effect on soil properties mentioned above, which might contribute to the blocking effect of its thick stem and leaves and the decomposition of fallen leaves, the network holding and reinforcement effect of developed root system. The ability of M. sativa for soil fixation and water conservation was weaker than V. zizanioides. But its root is deep and it also had good effects on the physical and chemical properties of surface soil. M. sativa is a good forage grass, and it is suitable for pastoral areas in slope land management used as hedgerow plant. The root of P. notatum is small and only distributed in shallow soil layer. But its ability in soil conservation and anti-scour was second only to V. zizanioides. Therefore, P. notatum is suitable for soil conserve in shallow landslide area. The effects of hedgerow on the properties of purple soil in sloping cropland are a complicated process. So a long-term and all-round monitor and multidisciplinary, thorough research are necessary.
(1)10°,15°坡耕地上,新银合欢植物篱和香根草植物篱均表现出一定的水土保持效应。据2010年和2011年径流小区的水土流失监测数据知,植物篱对泥沙的控制效应优于对径流的控制效应；同坡度时,香根草植物篱对径流泥沙的拦截效应优于新银合欢植物篱；定植时间较长时,植物篱的减流减沙效益较好,尤其表现在固土减沙方面；坡度对径流泥沙的影响显著于植物篱对径流泥沙的影响。定植2年后,植物篱改变坡耕地微地形的效应开始显现,且15°坡耕地比10°坡耕地、香根草植物篱比新银合欢植物篱、底行植物篱比中行、顶行植物篱稍明显。
(2)10°,15°坡耕地上,新银合欢植物篱和香根草植物篱小区表层(0-20cm)土壤机械组成和养分空间分布均发生变化。2010年,土壤机械组成和养分空间分布呈现一定规律：土壤细颗粒富集在坡脚、坡腰；养分富集在坡脚,坡顶的流失量减少；部分养分富集在篱带前。有机质在坡脚的富集最为明显,其次是全氮、总磷、有效磷和速效钾。有机质、全氮、碱解氮、有效磷、全钾和速效钾在篱带前均发生富集。10°坡地,香根草植物篱小区的细颗粒增量大于新银合欢植物篱小区,在拦截效果上,两种植物篱均表现为：砂粒>粉粒>粘粒。对全氮、有效磷、全钾的影响,新银合欢植物篱>香根草植物篱；对有机质、碱解氮、全磷、速效钾的影响,香根草植物篱>新银合欢植物篱。总体上,植物篱对全效养分的影响大于速效养分,香根草对土壤颗粒和养分分布的影响大于新银合欢。
2011年,总体上,土壤有机质、全氮、碱解氮、总磷、有效磷、全钾均减少,尤其是碱解氮和有效磷大幅度减少,速效钾则大量增加；植物篱对速效养分的影响大于全效养分。在坡面分布上,仅总磷的分布规律与2010年的类似,由坡顶向坡脚递增,其余养分的坡面分布规律与2010的差异较大。2011年的土壤养分数据及坡面分布规律极大异常,需要长期监测以探寻原因和正确揭示植物篱对土壤养分的影响规律及机制。
(3)10°,15°坡耕地上,新银合欢植物篱和香根草植物篱均能显著提高土壤中细菌、真菌和放线菌数量及微生物量碳氮含量、有机碳含量,其中土壤细菌数量、土壤微生物量碳氮含量较对照小区的增幅均在50%以上。总体上,香根草植物篱对上述各指标的影响大于新银合欢植物篱,尤其是对土壤微生物量氮含量的影响,10°坡耕地上香根草植物篱小区的增幅较新银合欢植物篱小区高30%余。坡度对上述微生物指标均有显著影响,10°坡较之15°坡更有利于上述指标的提高。各小区的上述微生物指标在坡面上呈现一个与2010年土壤养分相似的分布规律：由坡顶向坡脚递增,篱带前发生富集。其中,土壤真菌、土壤微生物量碳、土壤有机碳的富集较明显。各微生物指标均与土壤有机质、全氮、速效钾含量显著正相关,尤其是土壤有机质碳含量与土壤有机质含量,土壤有机碳含量与土壤全氮含量,土壤真菌数量与土壤速效钾含量。
(4)同一立地条件下,定植1年的紫花苜蓿、香根草、狗牙根、百喜草对紫色土表土(0-30cm)容重、孔隙度影响较显著且呈现一定规律性,对表土(0-20cm)机械组成几乎无影响,对表土(0-20cm)养分影响较弱。较对照小区,4个草本区表土容重降低,总孔隙度提高,土壤通透性得到改善,其中紫花苜蓿区最为明显。草本区,表土容重表现为：0-10cm土层<10-20cm土层<20-30cm土层,与根长密度RLD (root length density)的垂直分布相反；总孔隙度表现为：0-10cm土层>10-20cm土层>20-30cm土层,与RLD的垂直分布一致。相关分析知,L≤0.5mm和L>5mm径级的根系对降低表土容重,改善土壤孔隙性贡献最大；全氮、碱解氮与各径级根长密度RLD显著(极显著)相关,其他养分与各径级根长密度RLD相关性则不显著。
(5)同一立地条件下定植1年后,紫花苜蓿、香根草、狗牙根、百喜草的根系均能显著增强表土层(0-10,10-20,20-30cm)根-土复合体的抗剪性能。其中,香根草的增强效果最为显著：100～400kPa竖向荷载下,抗剪强度较对照提高117%～195%,紫花苜蓿、百喜草和狗牙根的提高幅度分别为：18%～125%,18%～186%,21%～68%。对照小区、香根草区、狗牙根区、百喜草区的抗剪强度指标(内摩擦角φ和粘聚力c)表现为：土层越深,值越小；紫花苜蓿区的趋势则相反。较之土壤含水率,根系对复合体抗剪性能的影响更显著。根本身的抗剪性能是影响复合体抗剪性能的关键,同径级百喜草根的抗剪性能优于紫花苜蓿根。各径级RLD与根干重显著或极显著相关,但各径级RLD与内摩擦角φ、粘聚力c,根干重与内摩擦角φ、粘聚力c均无显著相关。
(6)同一立地条件定植1年后,紫花苜蓿、香根草、狗牙根、百喜草的根系均能显著增强表土层(0-30cm)根-土复合体的抗冲性能,尤其是香根草和百喜草。冲刷试验的各特征时刻(1,2,3,4,7,10min),草本区的径流含沙量均小于对照小区,且表现为：香根草区<百喜草区<狗牙根区<紫花苜蓿区。紫花苜蓿区和香根草区的径流含沙量变化过程用二次函数拟合较好,对照区和百喜草区的用幂函数拟合较好。各试验小区的土壤抗冲指数ANS与冲刷时间t能较好地用用二次多项式进行拟合,香根草区和百喜草区的拟合效果最好,狗牙根区的拟合效果稍差。这4种根系对表土的抗冲性能均有很好的增强效果,其中香根草的增强效果最好,强化百分率高达277.53%,其次是百喜草。相关分析知：根长密度RLD与抗冲指数ANS显著相关,根表面积与抗冲指数ANS极显著相关。
紫色土区缓坡地,新银合欢植物篱和香根草植物篱对表土理化性质、微生物学性质、力学性质等产生有利影响,进而提高了土壤肥力、抗侵蚀能力和潜在生产力,作为一种生态型的坡耕地治理措施,值得推广。在定植的初期,香根草植物篱对上述各方面的影响效果较显著,这是其茂密茎叶、密实篱笆的机械拦截,较多易分解枯落物的腐解,发达根系的网络固持、加筋作用等共同产生的效应。紫花苜蓿固持土壤的能力较香根草弱,但其根系较香根草深、发达,对表土理化性质亦有较好的改善效果,且是一种良好的牧草,作为植物篱品种很适合在牧区的坡耕地治理中采用。百喜草根系形态小且在土层中分布浅,却具有仅次于香根草的固土抗冲效果,很适合在浅层滑坡地带采用。植物篱对紫色土坡地水土特性的影响是一个复杂的过程,其机理亦非常复杂,需要进行长期、全方位的监测与多学科、深入的研究。
Purple soil mainly distributes in the Sichuan Basin of China. Purple soil layer is shallow, loose, and extremely prone to soil erosion. Soil erosion in sloping cropland of purple soil is very serious. Hedgerow could control soil erosion, improve soil nutrient status, and regulate farmland microclimate. Hedgerow has good ecological, economic and social benefits. It is an important agronomic and biological measure to prevent soil erosion. Herbal hedgerow grows fast and has dense root system. The plant of herbal hedgerow is simple, and the cost is low, and it is able to conserve soil and protect slope in a relatively short time after the plant. Hence, herbal hedgerow is very suitable to be applied in hill areas for soil and water conservation. In this study, the soil conservation mechanisms of hedgerow were studied from both the underground system and the above-ground system of the hedgerow. The above-ground part was researched by growing Leucaena leucocephala and Vetiveria zizanioides hedgerows in standard runoff plots (10°,15°) and by analyzing soil physical, chemical and microbiological characteristics. The underground part was researched by growing grasses, Medicago sativa, V. zizanioides, Cynodon dactylon and Paspalum natatu. Root characteristics of herbs were analyzed by WinRHIZO root scanning system, and soil physical and chemical characteristics were analyzed, and anti-shear ability and anti-scourability were also measured. The effects of hedgerow on soil erosion, slope micromorphology, surface soil particle composition, nutrients distribution and microbial populations in purple soil sloping cropland were analyzed quantitatively. The main results are as follows:
(1) In sloping cropland of10°,15°, both L. leucocephala and V. zizanioides hedgerows showed soil and water conservation effects. According to the data of runoff plots monitored in2010and2011, the two kinds of hedgerows had better effect on sand sediment than on surface runoff. At the same declivity, V. zizanioides hedgerow demonstrated better ability than L. leucocephala hedgerow in controlling soil erosion.1year after the plant of hedgerow, declivity showed more obvious effect on soil erosion than hedges. But this phenomenon changed in the next year. The micromorphology of sloping cropland changed in hedgerow plots2years after the plant, represented as sand deposition before the hedgerows, slope declivity decreased between two hedgerows lines, and ridges formed under hedgerow lines. The hedgerow of V. zizanioides changed the micromorphology more significantly than that of L. leucocephala.
(2) In sloping cropland of10°,15°, the mechanical constitution and nutrient distribution of plots changed after the plant of hedgerow. In2010, small soil particle (silt and clay) accumulated at the foot and in the middle of the slope. The nutrient loss on the top of the slope reduced, and nutrients enriched at the foot of the slope, among which the enrichment of soil organic matter were most distinguishing, and the next were total nitrogen, total phosphorus, available phosphorus and available potassium, respectively. Total nitrogen did not enriched before hedgerows. The amount of total potassium increased in all plots. In10°sloping cropland, small soil particles increased more significantly under V. zizanioides hedgerow than that under L. leucocephala hedgerow. The intercept effects of these two kinds of hedgerows to soil particles were sand> silt> clay. L. leucocephala hedgerow affected total nitrogen, available phosphorus and total potassium more significantly than V. zizanioides hedgerow did, while V. zizanioides hedgerow affected soil organic matters, available nitrogen, total phosphorus and available potassium more significantly. In general, both kinds of hedgerows showed more significant effect on the total nutrients of soil than on available nutrients and V. zizanioides affected the redistribution of soil particles and nutrients more significantly than L. leucocephala did.
In2011, the effect of hedgerows on soil nutrient became more complex. On the whole, soil organic matter, total nitrogen and phosphorus, available nitrogen and phosphorus, total potassium reduced. But available potassium increased greatly. Hedgerows'effect on soil available nutrient was greater than on the total nutrient. In the slope distribution, only total phosphorus's distribution was similar as that in2010. Overall, soil nutrient contents and their slope distribution in2011were abnormal and long-term monitor is needed to explore the effect of hedgerows on soil nutrient characteristics.
(3) In sloping cropland of10°,15°, V. zizanioides and L. leucocephala both improved the content of bacteria, fungi, actinomyces, microbiological carbon, microbiological nitrogen, and organic matters in soil. The content of bacteria, microbiological carbon and microbiological nitrogen increased more than50%. In general, V. zizanioides improved soil microbiological indicators mentioned above more significantly than L. leucocephala did. Especially the content of microbiological nitrogen was30%higher in V. zizanioides plots than that in L. leucocephala plots at the same declivity. The slope declivity also affected the soil microbiological indicators mentioned above significantly. These indicators increased as the slope got more moderate. These soil microbiological indicators showed a similar distribution tendency as soil nutrient in2010:increasing progressively from the top to the bottom of slopes and enriching before hedgerow lines. The content of microbes demonstrated remarkable positive relation with soil organic matters, total nitrogen and available potassium.
(4) Under the same site, M. sativa, V. zizanioides, C. dactylon and P. notatum planted for1year had a significant effect on bulk density, porosity of surface soil layer (0-30cm), but they had almost no influence on soil particle composition and showed small influence on nutrients content of surface soil layer (0-20cm). Compared with control plots, soil bulk density decreased and total porosity increased in the4herbal plots. So soil aeration and water permeability had improved in herbal plots, especially in M. sativa Plot. In herbal plots, surface soil bulk density showed the opposite order of RLD (root length density) as0-10cm layer<10-20cm layer<20-30cm layer, but total porosity had the same order of RLD, shown as0-10cm layer>10-20cm layer>20-30cm layer. According to Spearman correlation analysis, roots of L≤0.5mm and L>5mm showed significant contributions to physical indicators mentioned above. Total nitrogen and available nitrogen showed significant correlations with RLD of all diameters, but other nutrients almost showed no correlation with RLD.
(5) Under the same site, after1year's plant, the root systems of M. sativa, V. zizanioides, C. dactylon and P. notatum could significantly strengthen anti-shear ability of root-soil complex in the surface soil layer (0-10,10-20,20-30cm), respectively. Among them the effect of V. zizanioides was the most significant:at100-400kPa vertical load, the anti-shear strength was improved117%-195%as compared with control, and the increase percentages of M. sativa, P. notatum and C. dactylon were18%-125%,18%-186%,21%-68%, respectively. In the plots of control, V. zizanioides, C. dactylon and P. notatum, anti-shear strength parameters (internal friction angle ψ, cohesionc) showed as:the soil layer got deeper, the value got smaller. The tendency in M. sativa plot was on the opposite. The root system showed stronger effect on the anti-shear ability of complex than on soil water content. The anti-shear ability of root was the key factor that improved root-soil complex anti-shear ability. The root of P. notatum had stronger anti-shear strength than that of M. sativa of the same diameter. Various diameters of RLD showed strong correlation with RDW (dry wet of root). But RLD showed no relation with φ andc, so as RDWto φ andc.
(6) Under the same site,1year after the plant, root systems of M. sativa, V. zizanioides, C. dactylon and P. notatum significantly strengthened the anti-scourability of root-soil complex from the surface soil layer (0-30cm), respectively. At different time points of scour experiment, the sand contents of runoff in the herb plots were lower than that of control plot, and showed the order as V. zizanioides
引文
[]Kang B T. Alley cropping:past achievements and future directions[J].Agro-forestry systems,1993,23(2):141-156.
[2]Versteeg M N, Koudokpon V. Participative fanner testing of four low external input technologies to address soil fertility decline in mono province(Benin)[J].Agricultural systems,1993,42:265-276.
[3]刘定辉.紫色丘陵区蓑草植物篱防治水土流失的效应及机理[D].北京：中国农业科学院,2006.
[4]张宇清,齐实.中国梯田生物埂研究：现状和方向[J].世界林业研究,2002,15(3)：49-53.
[5]王喜龙,蔡强国,王忠科,等.冀西北黄土丘陵沟壑区梯田地埂植物篱的固埂作用与效益分析[J].自然资源学报,2000,15(1)：74-79.
[6]刘学军,李秀彬.等高线植物篱提高坡地持续生产力研究进展[J].地理科学进展,1997,16(3)：69-79.
[7]龙高飞,蒲玉琳,谢疆.农业面源污染的植物篱控制技术研究进展.安徽农业科学,2011,39(19)：11711-11714,11717.
[8]Kusumandari A.Soil erosion and sediment yield in forest and agro-forestry area in west java, Indonesia[J]. Journal of soil and Water Conservation,1997,52(5):36-38.
[9]孙辉,唐亚,陈克明,等.固氮植物篱改善退化坡耕地土壤养分状况的效果[J].应用与环境生物学报,1999,5(5)：473-477.
[0]Kang B T, G F WlIson, L Sipkens. Alley cropping maize(Zeamays) and leucaena(Leucaenaleucocephala Lam) in southern Nigeria[J].Plant and Soil,1981,63:165-179.
[1]张炎周.等高固氮植物篱对横断山区农业产业结构调整作用的研究[J].四川林勘设计,2002,(1)：9-14.
[2]Adisak. SujjaPongse.Management of Slopingland for sustainable Agrieulture[M].Bangkok,Thailand:IBSRAM publication.2002:151-186.
[3]王幸.三峡库区几种植物篱效益研究[D].北京：北京林业大学,2011.
[4]钟勇.美国水土保持中的缓冲带技术[J].中国水利,2004(10)：63-65.
[5]董有浦.南方丘陵山地不同植物篱处理下水土流失研究[D].合肥：安徽农业大学,2009.
[6]Rodriguez O S.Hedgerows and mulch as soil conservation measures evaluated under field simulated rainfall[J].Soil Technology,1997,11(1):79-930.
[7]J.O. Owino, S.F.O. Owido, M.C. Chemelil. Nutrients in runoff from a clay loam soil protected by narrow grass strips [J]. Soil & Tillage Research.2006,88(1-2):116-122.
[8]Susama Sudhishri, Anchal Dass, N.K. Lenka. Efficacy of vegetative barriers for rehabilitation of degraded hill slopes in eastern India[J]. Soil & Tillage Research 2008,99 (1):98-107.
[9]李秀彬,施讯.等高活篱笆试验研究的若干问题[J].地理研究,1996,15(1)：66-72.
[20]董萍,严力蛟.利用植物篱防治水土流失的技术及其效益研究综述[J].土壤通报,2011,42(2)：491-496.
[2]尹迪信,唐华彬,罗红军.参与式植物篱坡地治理技术发展的实践和体会[J].贵州农业科学,2006,34(5)：107-111.
[22]李裕荣,尹迪信,韦小平,等.贵州植物篱梯化项目区农户对水保植物的参与式评价[J].贵州农业科学,2007, 35(5)：108-110.
[23]孙辉,唐亚,谢嘉穗,等.植物篱种植模式及其在我国的研究和应用[J].水土保持学报,2004,18(2)：114-117.
[24]聂军,廖育林,谢坚,等.自然降雨条件下香根草生物篱对菜地土壤地表径流和氮流失的影响[J].水土保持学报,2009,23(2)：12-16.
[25]张国华,张展羽,左长清,等.红壤坡地不同类型梯田的水土保持效应[J].水利水电科技进展,2007,27(2)：77-79.
[26]王燕,宋凤斌,刘阳,等.高植物篱种植模式及其应用中存在的问题[J].广西农业生物科学,2006,25(4)：370-374.
[27]陈一兵,林超文,黄晶晶.经济植物篱和增施钾肥综合效益研究[J].西南农业学报,2006,19(3)：404-408.
[28]Nakai K, Kanehisa M. A knowledge base for predicting protein localization sites in eukaryotic cells[J]. Genomics, 1992,14(4):897-911.
[29]Nelson R A, Cramb R A, Menz K M, et al. Cost-benefit analysis of alternative forms of hedgerow intercropping in the Philippine uplands [J]. Agroforestry Syst,1998,39 (3):241-262.
[30]Kilewe AM. Prediction of erosion rates and effects oftopsoil thickness on soil productivity[D]. University of Nairobi, Nairobi, Kenya,1987.
[3]Deizan M M, Mostaghimi S, Shanholtz V O, et al.Size distribution of eroded sediment from two tillage systems [J].Transaction of the ASAE,1987,30(6).
[32]Banda.A hedgerows on soil conservation and maize yield on a steep slope at Ntcheu, Malawi[J].Agroforestry Systems,1994,27(1):17-22.
[33]Kiepe P. No runoff, no soil loss:soil and water conservation in hedgerow barrier system [M]. Wageningen:W ageningen Agricutural Un ivers ity, Netherlands,1995.
[34]Narain P, singh R K, sindhwal N S, et al.Agroforestry for soil and water conservation in western Himalayan valley region of India:1.Runoff soil and nutrient loss[J].Agroforestry systems,1998,39(2):175-189.
[35]Machito Mihara. The effect of natural weed buffers on soil and nitrogen losses in Japan[J].Catena,2006,65 (3):265-271
[36]李秀彬,彭业轩,姜臣,等.等高活篱笆技术提高坡地持续生产力探讨——以三峡库区为例[J].地理研究,1998,17(3)：309-314.
[37]唐亚,谢嘉穗,陈克明,等.等高固氮植物篱技术在坡耕地可持续耕作中的应用[J].水土保持研究,2001,8(1)：104-109.
[38]许峰,蔡强国,吴淑安.等高植物篱控制紫色土坡耕地侵蚀的特点[J].土壤学报,2002,39(1)：71-80.
[39]谢庭生,罗蕾.紫色土丘陵侵蚀沟建植物篱自然植被恢复及水土流失特征研究[J].水土保持研究,2005,12(5)：63-65.
[40]卜崇峰,蔡强国,袁再健.湿润区坡地香根草植物篱农作措施对土壤侵蚀和养分的影响[J].农业工程学报,2006,22(5)：55-60.
[4]林超文,涂仕华,黄晶晶.植物篱对紫色土区坡耕地水土流失及土壤肥力的影响[J].生态学报,2007,27(6)：2191-2198.
[42]黄传伟,牛德奎,黄顶,等.草篱对坡耕地水土流失的影响[J].水土保持学报,2008,22(6)：40-43.
[43]张丽,刘玲花,程东升.不同农艺措施对坡耕地水土及氮磷流失的控制[J].水土保持学报,2009,23(5)：21-25
[44]姚桂枝,刘章勇.丹江口库区坡耕地不同植物篱对径流及养分流失的影响初探[J].安徽农业科学,2011,38(6)：3015-3016,3047.
[45]王利,吴述勇,张过师,等.不同植物篱在旱坡地柑橘园中的栽种效果[J].湖北农业科学,2011,50(16)：3272-3275.
[46]申元村.三峡库区植物篱坡地农业技术水土保持效益研究[J].土壤侵蚀与水土保持学报,1998,4(2)：61-66.
[47]申元村.三峡库区植物篱坡地农业技术提高土地生产潜力的研究[J].长江流域资源与环境,2002,11(1)：56-59.
[48]朱远达,蔡强国,张光远,等.植物篱对土壤养分流失的控制机理研究[J].长江流域资源与环境,2003,12(4)：345-351.
[49]廖晓勇,罗承德,陈治谏,等.三峡库区植物篱技术对坡耕地土壤肥力的影响[J].水土保持通报,2006,26(6)：1-3.
[50]黎建强,张洪江,程金花等.长江上游不同植物篱系统的土壤物理性质[J].应用生态学报,2011,22(2)：418424.
[5]黄丽,丁树文,董舟,等.三峡库区紫色土养分流失的试验研究[J].土壤侵蚀与水土保持学报,1998,4(1)：8-13.
[52]唐政洪,蔡强国,许峰,等.半干旱区植物篱侵蚀及养分控制过程的试验研究[J].地理研究,2001,20(5)：593-600.
[53]牛德奎,黄传伟,武菊英.草篱对坡耕地水土流失和土壤养分的影响[J].安徽农业科学,2009,37(7)：3079-3081,3084.
[54]龙会英,金杰,张德,等.豆科牧草和灌木在元谋干热河谷小流域综合治理的应用研究[J].水土保持研究,2010,17(2)：254-258.
[55]Groffmann PM, Zak DR., Christensen S, et al. Early spring nitrogen dynamics in a temperate forest landscape [J]. Ecology,1993,74:1579-1585.
[56]章家恩,刘文高,胡刚.不同土地利用方式下土壤微生物数量与土壤肥力的关系[J].土壤与环境,2002,11(2)：140-143.
[57]任佐华,张于光,李迪强,等.三江源地区高寒草原土壤微生物活性和微生物量[J].生态学报,2011,31(11)：3232-3238.
[58]宋秋华,李凤民,王俊.覆膜对春小麦农田微生物数量和土壤养分的影响[J].生态学报,2002,22(12)：2125-2132.
[59]郭天财,宋晓,马冬云.氮素营养水平对小麦根际微生物及土壤酶活性的影响[J].水土保持学报,2006,20(3)：129-131,140.
[60]陈利军,武志杰.与氮转化有关的土壤酶活性对抑制剂使用的响应[J].应用生态学报,2002,13(9)：1099-1101.
[6]王书锦,胡江春.新世纪中国土壤微生物学的展望[J].微生物学杂志,2002,22(1)：36-39.
[62]Bending G D, Turner M K, Jones J E. Interactions between crop residue and soil organic matter quality and the funcitional diversity of soil microbial communities [J]. Soil Biology and Biochemistry,2002,34(8):1073-1082.
[63]陈蓓,张仁陟.免耕与覆盖对土壤微生物数量及组成的影响[J].甘肃农业大学学报,2004,39(6)：634-638.
[64]张帆,黄凤球,肖小平,等.冬季作物对稻田土壤微生物量碳、氮和微生物熵的短期影响[J].生态学报,2009,29(2)：734-739.
[65]EkenlerM, TabatabaiM A. Effects of liming and tillage systems on microbial biomass and glycosidases in soils[J]. Biol. Fertil. Soils,2003,39:51-61.
[66]刘守龙,肖和艾,童成立.亚热带稻田土壤微生物生物量碳、氮、磷状况及其对施肥的反应特点[J].农业现代化研究,2003,24(4)：278-282.
[67]潘根兴.中国土壤有机碳和无机碳库量研究[J].科技通报,1999,15(5)：330-332.
[68]Gregorich E G, G reer K J, et al. Carbon distribution and losses:erosion and deposition effects [J]. Soil and Tillage Research,1998,47:291-3021.
[69]Collins K L, Boatman N D, Wilcox A, et al.Influence of beetle banks on cereal aphid predation in winter wheat[J]. Agriculture, Ecosystems and Environment,2002,93:337-350.
[70]Collins K L, Boatman N D, Wilcox A, et al.A 5-year comparison of overwintering polyphagous predator densities within a beetle bank and two conventional hedgebanks[J].Annals of Applied Biology,2003,143:63-71.
[7]Collins K L, Boatman N D, Wilcox A, et al.Effeets of different gass treatments used to create overwintering habitat for predatory arthropods on arable farmland[J].Agriculture, Ecosystems and Environment,2003,96:59-67.
[72]Huusela-Veistola E. Effeets of perennial grass strips on spiders(Aranaeae) in eereal fields and impacts on pesticide side-effects[J].Journal of Applied Entomology,1998,122:575-580.
[73]Girma H, Rao M R. Sithanantham S. iNseet pests and beneficial arthropod populations under different hedgero w intercropping systems in semiarid Kenya[J]. Agroforestry Systems,2000,50:279-292.
[74]Lemke A, Poehling H M.Sown weed strips in cereal fields:overwiniering site and"souree" habitat for Oedothorax apicatus(Blackwall) and Erigone atra (Blackwall) (Araneae:Erigonidae)[J]. Agriculture, Ecosystems and Environment, 2002,90:67-80.
[75]吴玉红,蔡青年,林超文,等.地埂植物篱对大型土壤动物多样性的影响[J].生态学报,2009,19(10)：5320-5329.
[76]林超文.不同种类植物篱对紫色丘陵区坡耕地农田生态的影响机制[D].四川雅安：四川农业大学,2009.
[77]朱钟麟,陈一兵.经济植物篱主要模式及其生态经济效益研究[J].西南农业学报,2005,18(6)：715-718.
[78]陈治谏,廖晓勇,刘邵权.坡地植物篱农业技术生态经济效益评价[J].水土保持学报,2003,17(4)：125-127,160.
[79]史亮涛,金杰,张明忠,等.云南干热河谷旱坡地南洋樱植物篱水土保持效益研究[J].草原与草坪,2010,30(4)：76-80.
[80]袁运亮,孙辉唐亚.等高固氮植物篱间作甘蔗技术[J].甘蔗,2002,9(3)：6-8.
[8]陈一兵,林超文,黄晶晶.经济植物篱和增施钾肥综合效益研究[J].西南农业学报,2006,19(3)：404-408.
[82]Alege J C, Rao M R. Soil and water conservation by contour hedging in the humid tropics of Peru[J]. Agriculture, Eeosystems and Environment,1996,57:17-25.
[83]Shively G E. Impact of contour hedgerows on upland maize yields in the Philippines[J]. Agroforestry Systems, 1998,39:59-71.
[84]Maclean R H, Litsinger J A, Moody K, et al.Impact of Gliricidia sepium and Cassia spectabilis hedgerows on weeds and insect pests of upland rice[J]. Agriculture, Ecosystems and Environment,2003,94:275-288.
[85]袁远亮孙辉唐亚.等高固氮植物篱脐橙园综合效益分析[J].中国生态农业学报,2001,9(4)：76-78.
[86]李裕荣,严迪信,韦小平,等.贵州植物篱梯化项目区农户对水土保持植物的参与式评价[J].贵州农业科学,2007,35(5)：108-110.
[87]祝其丽,孙辉,何道文.植物篱种植模式综合效益研究[J].四川环境,2007,26(3)：41-45.
[88]姜凡.植物篱条件下南方红壤坡耕地土壤抗蚀性特征研究[D].杭州：浙江大学,2011.
[89]徐汉卿.植物学(第1版)[M].北京：中国农业出版,1996：68-70.
[90]沈连生.药用植物学(第1版)[M].北京：中国医药科技出版社,1987：68-70.
[9]根[R/OL].互动百科.http://www.hudong.com.
[92]张喜英.作物根系与土壤水利用(第1版)[M].北京：气象出版社,199：1,7-10.
[93]草本植物[R/OL].互动百科.http://fun.hudong. com.
[94]周德培,张俊云.植被护坡工程技术[M].北京：人民交通出版社,2003.
[95]鄢朝勇,叶建军,韦书勇.植被对边坡浅层稳定的影响[J].水土保持研究,2007,14(1)：24-28.
[96]谌芸,祝亚军,何丙辉.三峡库区狗牙根根系固坡抗蚀效应研究[J].水土保持学报,2010,24(6)：42-45.
[97]Hales S. Vegetable Stacicks[M].Reprint:London:Macdonald,1961.
[98]孙浩.滴灌土壤水分分布与棉花根系分布关系的试验研究[D].石河子：石河子大学,2009.
[99]王文生,杨晓华,谢永利.公路边坡植物的护坡机理[J].长安大学学报(自然科学版),2005,25(4)：26-30.
[00]Quido Zaruba, Vojtech Mencl. Landslides and their control [M]. Amsterdam:Elsevier Science & Technology, 1969:54-57.
[10]Holch A E.Development of roots and shoots of certain deciduous tree seedlings in different forest sites[J]. Eeology,1931,12(2):259-298.
[02]程洪,颜传盛,李建庆,等.草本植物根系网的固土机制模式与力学试验研究[J].水土保持研究,2006,13(1)：62-65.
[03]周云艳.植物根系固土机理与护坡技术研究[D].武汉：中国地质大学,2010
[04]乔娜,余芹芹,胡夏嵩,等.植物对土壤加强作用及其生态护坡研究综述[J].人民黄河,2011,33(7)：106-109.
[05]王治国,张云龙,刘徐师,等.林业生态工程学：林草植被建设的理论与实践[M].北京：中国林业出版社,2000.
[06]Endo T, Tsuruta T.The effect of tree roots upon the shearing strength of soil.Annual report of the Hokkaido Branch, Tokyo Forest Experiment station, Tokyo, Japan,1969(18):168-179.
[07]Ziemer R R. Roots and stability of forested slopes.Publication No.132, Int. Assoc. of Hydrologic Sciences, 1981:343-361.
[08]杨亚川,莫永京,王芝芳,等.土壤-草本植被根系复合体抗水蚀强度与抗剪强度的试验研究[J].中国农业大学学报,1996,1(2)：31-38.
[09]Bischetti GB,Chiaradia EA,Simonato T,et al. Root strength and root area ratio of forest species in Lombardy (Northern Italy) [J]. Plant and Soil,2005,278:11-22.
[10]杨永红,王成华,刘淑珍,等.不同植被类型提高浅层滑坡土体抗剪强度的试验研究[J].水土保持研究,2007,14(2)：233-235.
[11]张兴玲,胡夏嵩,李国荣,等.寒旱环境草本植物根系护坡的时间尺度效应[J].水文地质工程地质,2009(4)：117-120.
[12]刘向东,吴钦孝,赵鸿雁.森林植被垂直截留作用与水土保持[J].水土保持研究,1994,1(3)：8-13.
[13]杜峰,程积民.植被与水土流失[J].四川草原,1999,(2)：6-11.
[14]刘定辉,李勇.植物根系提高土壤抗侵蚀性机理研究[J].水土保持学报,2003,17(3)：34-37.
[15]王库.植物根系对土壤抗侵蚀能力的影响[J].土壤与环境,2001,10(3)：250-252.
[16]Gyssels G, Poesen J, Bochet E, et al. Impact of plant roots on the resistance of soils to erosion by water:Areview [J]. Progress in Physical Geography,2005,29:189-217.
[17]de Baets S, Poesen J, Gyssels G, et al. Effects of grass roots on the erodibility of top soils during concentrated flow [J]. Geomorphology,2006,76:54-67.
[18]蒋定生.黄土高原水土流失与治理模式[M].北京：中国水利水电出版社,1997.
[19]卢喜平,史东梅,蒋光毅,等.两种果草模式根系提高土壤抗蚀性的研究[J].水土保持学报,2004,18(5)：64-67.
[20]王礼先.中国水利百科全书·水土保持分册[M].北京：中国水利水电出版社.2004：31.
[21]谌芸,马云,何丙辉.植物篱对紫色土物理性质及养分的影响[J].水土保持学报,2011,25(6)：59-63.
[22]二级建造：谈谈边坡的生态防护[R/OL].考吧.[2008-11-26]http://www.exam8.com.
[23]吴希媛,张丽萍.坡地水土流失对水体富营养化贡献的研究进展[J].水土保持研究,2006,13(5)：296-298.
[24]谌芸,何丙辉,赵秀兰,等.小江流域农地水土流失对水体富营养化的影响[J].水土保持学报,2010,24(4)：31-34
[25]黎华寿,蔡庆.水土保持工程植物运用图解[M].北京：化学工业出版社,2007：216.
[26]马云.紫色土区控制面源污染植物篱模式及带间距研究[D].重庆：西南大学,2011.
[27]谢颂华,曾建玲,杨洁,等.南方红壤坡地不同耕作措施的水土保持效应[J].农业工程学报,2010,26(9)：81-86.
[28]李广,黄高宝.雨强和土地利用方式对黄土丘陵区水土流失的影响[J].农业工程学报,2009，25(11)：85-89.
[29]中华人民共和国国家标准.水土保持综合治理效益计算方法(GB/T15774-2008)[S].北京：国家质量监督检验检疫总局发布,2008.
[30]卜崇峰,蔡强国,袁再健,等三峡库区等高植物篱的控蚀效益及机制[J].中国水土保持科技,2006,4(4)：14-18.
[31]孙鸿烈,刘光崧.土壤理化分析与坡面描述[M].北京：中国标准出版社,1996：8.
[32]刘光崧.土壤理化分析与剖面描述[M].北京：中国标准出版社,1996：5-7,32.
[33]黄冠华,詹卫华.土壤颗粒的分形特征及其应用[J].土壤学报,2002,39(4)：490-497.
[34]ZHANG J H, LOBB D A, LI Y, et al.Assessment for tillage translocation and tillage erosion by hoeing on the steep land in hilly areas of Sichuan, China[J].Soil Tillage and Research,2004,75:99-107.
[35]蔡强国.黄土高原侵蚀产沙过程与模拟[M].北京：科学出版社.1998：1-150.
[36]张季如,朱瑞赓,祝文化.用粒径的数量分布表征的土壤分形特征[J].水利学报,2004,(4)：1-6.
[37]韩方虎.苜蓿草地土壤氮素矿化的研究[D].兰州：兰州大学,2008.
[38]沈萍,范秀容,李广武.微生物学实验[M].北京：高等教育出版社,1999：92-95.
[39]吴金水,林启美,黄巧云,等.土壤微生物微生物量测定方法及其应用[M].北京：气象出版社,2006：56-60.
[40]鲁如坤.土壤农业化学分析方法[M].北京：中国农业科技出版社,2000.
[41]郭甜,何丙辉,蒋先军,等.紫色土区植物篱对坡面土壤微生物特性的影响[J].水土保持学报,2011,25(5)：94-98,185.
[42]李博.鄂尔多斯高原的自然条件与草地资源概况[A].鄂尔多斯高原沙质灌木草地绒山羊试验区研究所成果汇编[C].呼和浩特：内蒙古教育出版社,1995,1-6.
[43]Jizhong Zhou, Dorothea K. Thompson, Ying Xu et al. Microbial Functional Genomics [M]. A John Wiley & Sons, Inc., Publication, the United States of America,2004,21-40.
[44]巍强,张秋良,代海燕,等.大青山不同林地类型土壤特性及其水源涵养功能[J].水土保持学报,2008,22(2)：111-115.
[45]杨洁,喻荣岗,王照艳,等.红壤侵蚀区优良水土保持草本植物的选择及评价[J].中国水土保持,2009,(3)：25-28.
[46]潘伟彬,邓恢.4种草本水土保持植物的耐旱生理特性[J].华侨大学学报(自然科学版),2009,30(3)：305-308.
[47]成向荣,黄明斌,邵明安,等.紫花苜蓿和短花针茅根系分布与土壤水分研究[J].草地学报,2008,16(2)：170-175.
[48]徐少君,曾波,类淑桐等.三峡库区几种耐水淹植物根系特征与土壤抗水蚀增强效应[J].土壤学报,2011,18(1)：160-165.
[49]韩凤朋,郑纪勇,张兴昌.黄土退耕坡地植物根系分布特征及其对土壤养分的影响[J].农业工程学报,2009,25(2)：50-55.
[50]李勇,张睛雯,李璐,等.黄土区植物根系对营养元素在土壤剖面中迁移强度的影响[J].植物营养与肥料学报,2005,11(4)：427-434.
[51]王燕,王兵,赵广东,等.江西大岗山3种林型土壤水分物理性质研究[J].水土保持学报,2008,22(1)：151-153.
[52]徐艳梅.四种退耕还林(草)模式土壤理化性质及酶活性动态研究[D].雅安：四川农业大学,2007.
[53]王治国,张云龙,刘徐师,等.林业生态工程学：林草植被建设的理论与实践[M].北京：中国林业出版社,2000.
[54]史东梅,陈晏.紫色丘陵区农林混作模式的土壤抗冲性影响因素[J].中国农业科学,2008,41(5)：1400-1409.
[55]陈晏,史东梅,文卓立,等.紫色土丘陵区不同土地利用类型土壤抗冲性特征研究[J].水土保持学报,2007,21(2)：24-27.
[56]陈希哲.土力学地基基础(第4版)[M].北京：清华大学出版社,2004：162-163.
[157]丁军,王兆骞,陈欣,等.红壤丘陵区林地根系对土壤抗冲增强效应的研究[J].水土保持学报,2002,16(4)：9-12.
[158]张建军,张宝颖,毕华兴,等.黄土区不同植被条件下的土壤抗冲性[J].北京林业大学学报,2004,26(6)：25-29.
[159]胡建忠,周心澄,李文忠,等.退耕地青海云杉人工林土壤抗冲性试验研究[J].水土保持学报,2004,18(6)：6-10.
[2]Versteeg M N, Koudokpon V. Participative fanner testing of four low external input technologies to address soil fertility decline in mono province(Benin)[J].Agricultural systems,1993,42:265-276.
[3]刘定辉.紫色丘陵区蓑草植物篱防治水土流失的效应及机理[D].北京：中国农业科学院,2006.
[4]张宇清,齐实.中国梯田生物埂研究：现状和方向[J].世界林业研究,2002,15(3)：49-53.
[5]王喜龙,蔡强国,王忠科,等.冀西北黄土丘陵沟壑区梯田地埂植物篱的固埂作用与效益分析[J].自然资源学报,2000,15(1)：74-79.
[6]刘学军,李秀彬.等高线植物篱提高坡地持续生产力研究进展[J].地理科学进展,1997,16(3)：69-79.
[7]龙高飞,蒲玉琳,谢疆.农业面源污染的植物篱控制技术研究进展.安徽农业科学,2011,39(19)：11711-11714,11717.
[8]Kusumandari A.Soil erosion and sediment yield in forest and agro-forestry area in west java, Indonesia[J]. Journal of soil and Water Conservation,1997,52(5):36-38.
[9]孙辉,唐亚,陈克明,等.固氮植物篱改善退化坡耕地土壤养分状况的效果[J].应用与环境生物学报,1999,5(5)：473-477.
[0]Kang B T, G F WlIson, L Sipkens. Alley cropping maize(Zeamays) and leucaena(Leucaenaleucocephala Lam) in southern Nigeria[J].Plant and Soil,1981,63:165-179.
[1]张炎周.等高固氮植物篱对横断山区农业产业结构调整作用的研究[J].四川林勘设计,2002,(1)：9-14.
[2]Adisak. SujjaPongse.Management of Slopingland for sustainable Agrieulture[M].Bangkok,Thailand:IBSRAM publication.2002:151-186.
[3]王幸.三峡库区几种植物篱效益研究[D].北京：北京林业大学,2011.
[4]钟勇.美国水土保持中的缓冲带技术[J].中国水利,2004(10)：63-65.
[5]董有浦.南方丘陵山地不同植物篱处理下水土流失研究[D].合肥：安徽农业大学,2009.
[6]Rodriguez O S.Hedgerows and mulch as soil conservation measures evaluated under field simulated rainfall[J].Soil Technology,1997,11(1):79-930.
[7]J.O. Owino, S.F.O. Owido, M.C. Chemelil. Nutrients in runoff from a clay loam soil protected by narrow grass strips [J]. Soil & Tillage Research.2006,88(1-2):116-122.
[8]Susama Sudhishri, Anchal Dass, N.K. Lenka. Efficacy of vegetative barriers for rehabilitation of degraded hill slopes in eastern India[J]. Soil & Tillage Research 2008,99 (1):98-107.
[9]李秀彬,施讯.等高活篱笆试验研究的若干问题[J].地理研究,1996,15(1)：66-72.
[20]董萍,严力蛟.利用植物篱防治水土流失的技术及其效益研究综述[J].土壤通报,2011,42(2)：491-496.
[2]尹迪信,唐华彬,罗红军.参与式植物篱坡地治理技术发展的实践和体会[J].贵州农业科学,2006,34(5)：107-111.
[22]李裕荣,尹迪信,韦小平,等.贵州植物篱梯化项目区农户对水保植物的参与式评价[J].贵州农业科学,2007, 35(5)：108-110.
[23]孙辉,唐亚,谢嘉穗,等.植物篱种植模式及其在我国的研究和应用[J].水土保持学报,2004,18(2)：114-117.
[24]聂军,廖育林,谢坚,等.自然降雨条件下香根草生物篱对菜地土壤地表径流和氮流失的影响[J].水土保持学报,2009,23(2)：12-16.
[25]张国华,张展羽,左长清,等.红壤坡地不同类型梯田的水土保持效应[J].水利水电科技进展,2007,27(2)：77-79.
[26]王燕,宋凤斌,刘阳,等.高植物篱种植模式及其应用中存在的问题[J].广西农业生物科学,2006,25(4)：370-374.
[27]陈一兵,林超文,黄晶晶.经济植物篱和增施钾肥综合效益研究[J].西南农业学报,2006,19(3)：404-408.
[28]Nakai K, Kanehisa M. A knowledge base for predicting protein localization sites in eukaryotic cells[J]. Genomics, 1992,14(4):897-911.
[29]Nelson R A, Cramb R A, Menz K M, et al. Cost-benefit analysis of alternative forms of hedgerow intercropping in the Philippine uplands [J]. Agroforestry Syst,1998,39 (3):241-262.
[30]Kilewe AM. Prediction of erosion rates and effects oftopsoil thickness on soil productivity[D]. University of Nairobi, Nairobi, Kenya,1987.
[3]Deizan M M, Mostaghimi S, Shanholtz V O, et al.Size distribution of eroded sediment from two tillage systems [J].Transaction of the ASAE,1987,30(6).
[32]Banda.A hedgerows on soil conservation and maize yield on a steep slope at Ntcheu, Malawi[J].Agroforestry Systems,1994,27(1):17-22.
[33]Kiepe P. No runoff, no soil loss:soil and water conservation in hedgerow barrier system [M]. Wageningen:W ageningen Agricutural Un ivers ity, Netherlands,1995.
[34]Narain P, singh R K, sindhwal N S, et al.Agroforestry for soil and water conservation in western Himalayan valley region of India:1.Runoff soil and nutrient loss[J].Agroforestry systems,1998,39(2):175-189.
[35]Machito Mihara. The effect of natural weed buffers on soil and nitrogen losses in Japan[J].Catena,2006,65 (3):265-271
[36]李秀彬,彭业轩,姜臣,等.等高活篱笆技术提高坡地持续生产力探讨——以三峡库区为例[J].地理研究,1998,17(3)：309-314.
[37]唐亚,谢嘉穗,陈克明,等.等高固氮植物篱技术在坡耕地可持续耕作中的应用[J].水土保持研究,2001,8(1)：104-109.
[38]许峰,蔡强国,吴淑安.等高植物篱控制紫色土坡耕地侵蚀的特点[J].土壤学报,2002,39(1)：71-80.
[39]谢庭生,罗蕾.紫色土丘陵侵蚀沟建植物篱自然植被恢复及水土流失特征研究[J].水土保持研究,2005,12(5)：63-65.
[40]卜崇峰,蔡强国,袁再健.湿润区坡地香根草植物篱农作措施对土壤侵蚀和养分的影响[J].农业工程学报,2006,22(5)：55-60.
[4]林超文,涂仕华,黄晶晶.植物篱对紫色土区坡耕地水土流失及土壤肥力的影响[J].生态学报,2007,27(6)：2191-2198.
[42]黄传伟,牛德奎,黄顶,等.草篱对坡耕地水土流失的影响[J].水土保持学报,2008,22(6)：40-43.
[43]张丽,刘玲花,程东升.不同农艺措施对坡耕地水土及氮磷流失的控制[J].水土保持学报,2009,23(5)：21-25
[44]姚桂枝,刘章勇.丹江口库区坡耕地不同植物篱对径流及养分流失的影响初探[J].安徽农业科学,2011,38(6)：3015-3016,3047.
[45]王利,吴述勇,张过师,等.不同植物篱在旱坡地柑橘园中的栽种效果[J].湖北农业科学,2011,50(16)：3272-3275.
[46]申元村.三峡库区植物篱坡地农业技术水土保持效益研究[J].土壤侵蚀与水土保持学报,1998,4(2)：61-66.
[47]申元村.三峡库区植物篱坡地农业技术提高土地生产潜力的研究[J].长江流域资源与环境,2002,11(1)：56-59.
[48]朱远达,蔡强国,张光远,等.植物篱对土壤养分流失的控制机理研究[J].长江流域资源与环境,2003,12(4)：345-351.
[49]廖晓勇,罗承德,陈治谏,等.三峡库区植物篱技术对坡耕地土壤肥力的影响[J].水土保持通报,2006,26(6)：1-3.
[50]黎建强,张洪江,程金花等.长江上游不同植物篱系统的土壤物理性质[J].应用生态学报,2011,22(2)：418424.
[5]黄丽,丁树文,董舟,等.三峡库区紫色土养分流失的试验研究[J].土壤侵蚀与水土保持学报,1998,4(1)：8-13.
[52]唐政洪,蔡强国,许峰,等.半干旱区植物篱侵蚀及养分控制过程的试验研究[J].地理研究,2001,20(5)：593-600.
[53]牛德奎,黄传伟,武菊英.草篱对坡耕地水土流失和土壤养分的影响[J].安徽农业科学,2009,37(7)：3079-3081,3084.
[54]龙会英,金杰,张德,等.豆科牧草和灌木在元谋干热河谷小流域综合治理的应用研究[J].水土保持研究,2010,17(2)：254-258.
[55]Groffmann PM, Zak DR., Christensen S, et al. Early spring nitrogen dynamics in a temperate forest landscape [J]. Ecology,1993,74:1579-1585.
[56]章家恩,刘文高,胡刚.不同土地利用方式下土壤微生物数量与土壤肥力的关系[J].土壤与环境,2002,11(2)：140-143.
[57]任佐华,张于光,李迪强,等.三江源地区高寒草原土壤微生物活性和微生物量[J].生态学报,2011,31(11)：3232-3238.
[58]宋秋华,李凤民,王俊.覆膜对春小麦农田微生物数量和土壤养分的影响[J].生态学报,2002,22(12)：2125-2132.
[59]郭天财,宋晓,马冬云.氮素营养水平对小麦根际微生物及土壤酶活性的影响[J].水土保持学报,2006,20(3)：129-131,140.
[60]陈利军,武志杰.与氮转化有关的土壤酶活性对抑制剂使用的响应[J].应用生态学报,2002,13(9)：1099-1101.
[6]王书锦,胡江春.新世纪中国土壤微生物学的展望[J].微生物学杂志,2002,22(1)：36-39.
[62]Bending G D, Turner M K, Jones J E. Interactions between crop residue and soil organic matter quality and the funcitional diversity of soil microbial communities [J]. Soil Biology and Biochemistry,2002,34(8):1073-1082.
[63]陈蓓,张仁陟.免耕与覆盖对土壤微生物数量及组成的影响[J].甘肃农业大学学报,2004,39(6)：634-638.
[64]张帆,黄凤球,肖小平,等.冬季作物对稻田土壤微生物量碳、氮和微生物熵的短期影响[J].生态学报,2009,29(2)：734-739.
[65]EkenlerM, TabatabaiM A. Effects of liming and tillage systems on microbial biomass and glycosidases in soils[J]. Biol. Fertil. Soils,2003,39:51-61.
[66]刘守龙,肖和艾,童成立.亚热带稻田土壤微生物生物量碳、氮、磷状况及其对施肥的反应特点[J].农业现代化研究,2003,24(4)：278-282.
[67]潘根兴.中国土壤有机碳和无机碳库量研究[J].科技通报,1999,15(5)：330-332.
[68]Gregorich E G, G reer K J, et al. Carbon distribution and losses:erosion and deposition effects [J]. Soil and Tillage Research,1998,47:291-3021.
[69]Collins K L, Boatman N D, Wilcox A, et al.Influence of beetle banks on cereal aphid predation in winter wheat[J]. Agriculture, Ecosystems and Environment,2002,93:337-350.
[70]Collins K L, Boatman N D, Wilcox A, et al.A 5-year comparison of overwintering polyphagous predator densities within a beetle bank and two conventional hedgebanks[J].Annals of Applied Biology,2003,143:63-71.
[7]Collins K L, Boatman N D, Wilcox A, et al.Effeets of different gass treatments used to create overwintering habitat for predatory arthropods on arable farmland[J].Agriculture, Ecosystems and Environment,2003,96:59-67.
[72]Huusela-Veistola E. Effeets of perennial grass strips on spiders(Aranaeae) in eereal fields and impacts on pesticide side-effects[J].Journal of Applied Entomology,1998,122:575-580.
[73]Girma H, Rao M R. Sithanantham S. iNseet pests and beneficial arthropod populations under different hedgero w intercropping systems in semiarid Kenya[J]. Agroforestry Systems,2000,50:279-292.
[74]Lemke A, Poehling H M.Sown weed strips in cereal fields:overwiniering site and"souree" habitat for Oedothorax apicatus(Blackwall) and Erigone atra (Blackwall) (Araneae:Erigonidae)[J]. Agriculture, Ecosystems and Environment, 2002,90:67-80.
[75]吴玉红,蔡青年,林超文,等.地埂植物篱对大型土壤动物多样性的影响[J].生态学报,2009,19(10)：5320-5329.
[76]林超文.不同种类植物篱对紫色丘陵区坡耕地农田生态的影响机制[D].四川雅安：四川农业大学,2009.
[77]朱钟麟,陈一兵.经济植物篱主要模式及其生态经济效益研究[J].西南农业学报,2005,18(6)：715-718.
[78]陈治谏,廖晓勇,刘邵权.坡地植物篱农业技术生态经济效益评价[J].水土保持学报,2003,17(4)：125-127,160.
[79]史亮涛,金杰,张明忠,等.云南干热河谷旱坡地南洋樱植物篱水土保持效益研究[J].草原与草坪,2010,30(4)：76-80.
[80]袁运亮,孙辉唐亚.等高固氮植物篱间作甘蔗技术[J].甘蔗,2002,9(3)：6-8.
[8]陈一兵,林超文,黄晶晶.经济植物篱和增施钾肥综合效益研究[J].西南农业学报,2006,19(3)：404-408.
[82]Alege J C, Rao M R. Soil and water conservation by contour hedging in the humid tropics of Peru[J]. Agriculture, Eeosystems and Environment,1996,57:17-25.
[83]Shively G E. Impact of contour hedgerows on upland maize yields in the Philippines[J]. Agroforestry Systems, 1998,39:59-71.
[84]Maclean R H, Litsinger J A, Moody K, et al.Impact of Gliricidia sepium and Cassia spectabilis hedgerows on weeds and insect pests of upland rice[J]. Agriculture, Ecosystems and Environment,2003,94:275-288.
[85]袁远亮孙辉唐亚.等高固氮植物篱脐橙园综合效益分析[J].中国生态农业学报,2001,9(4)：76-78.
[86]李裕荣,严迪信,韦小平,等.贵州植物篱梯化项目区农户对水土保持植物的参与式评价[J].贵州农业科学,2007,35(5)：108-110.
[87]祝其丽,孙辉,何道文.植物篱种植模式综合效益研究[J].四川环境,2007,26(3)：41-45.
[88]姜凡.植物篱条件下南方红壤坡耕地土壤抗蚀性特征研究[D].杭州：浙江大学,2011.
[89]徐汉卿.植物学(第1版)[M].北京：中国农业出版,1996：68-70.
[90]沈连生.药用植物学(第1版)[M].北京：中国医药科技出版社,1987：68-70.
[9]根[R/OL].互动百科.http://www.hudong.com.
[92]张喜英.作物根系与土壤水利用(第1版)[M].北京：气象出版社,199：1,7-10.
[93]草本植物[R/OL].互动百科.http://fun.hudong. com.
[94]周德培,张俊云.植被护坡工程技术[M].北京：人民交通出版社,2003.
[95]鄢朝勇,叶建军,韦书勇.植被对边坡浅层稳定的影响[J].水土保持研究,2007,14(1)：24-28.
[96]谌芸,祝亚军,何丙辉.三峡库区狗牙根根系固坡抗蚀效应研究[J].水土保持学报,2010,24(6)：42-45.
[97]Hales S. Vegetable Stacicks[M].Reprint:London:Macdonald,1961.
[98]孙浩.滴灌土壤水分分布与棉花根系分布关系的试验研究[D].石河子：石河子大学,2009.
[99]王文生,杨晓华,谢永利.公路边坡植物的护坡机理[J].长安大学学报(自然科学版),2005,25(4)：26-30.
[00]Quido Zaruba, Vojtech Mencl. Landslides and their control [M]. Amsterdam:Elsevier Science & Technology, 1969:54-57.
[10]Holch A E.Development of roots and shoots of certain deciduous tree seedlings in different forest sites[J]. Eeology,1931,12(2):259-298.
[02]程洪,颜传盛,李建庆,等.草本植物根系网的固土机制模式与力学试验研究[J].水土保持研究,2006,13(1)：62-65.
[03]周云艳.植物根系固土机理与护坡技术研究[D].武汉：中国地质大学,2010
[04]乔娜,余芹芹,胡夏嵩,等.植物对土壤加强作用及其生态护坡研究综述[J].人民黄河,2011,33(7)：106-109.
[05]王治国,张云龙,刘徐师,等.林业生态工程学：林草植被建设的理论与实践[M].北京：中国林业出版社,2000.
[06]Endo T, Tsuruta T.The effect of tree roots upon the shearing strength of soil.Annual report of the Hokkaido Branch, Tokyo Forest Experiment station, Tokyo, Japan,1969(18):168-179.
[07]Ziemer R R. Roots and stability of forested slopes.Publication No.132, Int. Assoc. of Hydrologic Sciences, 1981:343-361.
[08]杨亚川,莫永京,王芝芳,等.土壤-草本植被根系复合体抗水蚀强度与抗剪强度的试验研究[J].中国农业大学学报,1996,1(2)：31-38.
[09]Bischetti GB,Chiaradia EA,Simonato T,et al. Root strength and root area ratio of forest species in Lombardy (Northern Italy) [J]. Plant and Soil,2005,278:11-22.
[10]杨永红,王成华,刘淑珍,等.不同植被类型提高浅层滑坡土体抗剪强度的试验研究[J].水土保持研究,2007,14(2)：233-235.
[11]张兴玲,胡夏嵩,李国荣,等.寒旱环境草本植物根系护坡的时间尺度效应[J].水文地质工程地质,2009(4)：117-120.
[12]刘向东,吴钦孝,赵鸿雁.森林植被垂直截留作用与水土保持[J].水土保持研究,1994,1(3)：8-13.
[13]杜峰,程积民.植被与水土流失[J].四川草原,1999,(2)：6-11.
[14]刘定辉,李勇.植物根系提高土壤抗侵蚀性机理研究[J].水土保持学报,2003,17(3)：34-37.
[15]王库.植物根系对土壤抗侵蚀能力的影响[J].土壤与环境,2001,10(3)：250-252.
[16]Gyssels G, Poesen J, Bochet E, et al. Impact of plant roots on the resistance of soils to erosion by water:Areview [J]. Progress in Physical Geography,2005,29:189-217.
[17]de Baets S, Poesen J, Gyssels G, et al. Effects of grass roots on the erodibility of top soils during concentrated flow [J]. Geomorphology,2006,76:54-67.
[18]蒋定生.黄土高原水土流失与治理模式[M].北京：中国水利水电出版社,1997.
[19]卢喜平,史东梅,蒋光毅,等.两种果草模式根系提高土壤抗蚀性的研究[J].水土保持学报,2004,18(5)：64-67.
[20]王礼先.中国水利百科全书·水土保持分册[M].北京：中国水利水电出版社.2004：31.
[21]谌芸,马云,何丙辉.植物篱对紫色土物理性质及养分的影响[J].水土保持学报,2011,25(6)：59-63.
[22]二级建造：谈谈边坡的生态防护[R/OL].考吧.[2008-11-26]http://www.exam8.com.
[23]吴希媛,张丽萍.坡地水土流失对水体富营养化贡献的研究进展[J].水土保持研究,2006,13(5)：296-298.
[24]谌芸,何丙辉,赵秀兰,等.小江流域农地水土流失对水体富营养化的影响[J].水土保持学报,2010,24(4)：31-34
[25]黎华寿,蔡庆.水土保持工程植物运用图解[M].北京：化学工业出版社,2007：216.
[26]马云.紫色土区控制面源污染植物篱模式及带间距研究[D].重庆：西南大学,2011.
[27]谢颂华,曾建玲,杨洁,等.南方红壤坡地不同耕作措施的水土保持效应[J].农业工程学报,2010,26(9)：81-86.
[28]李广,黄高宝.雨强和土地利用方式对黄土丘陵区水土流失的影响[J].农业工程学报,2009，25(11)：85-89.
[29]中华人民共和国国家标准.水土保持综合治理效益计算方法(GB/T15774-2008)[S].北京：国家质量监督检验检疫总局发布,2008.
[30]卜崇峰,蔡强国,袁再健,等三峡库区等高植物篱的控蚀效益及机制[J].中国水土保持科技,2006,4(4)：14-18.
[31]孙鸿烈,刘光崧.土壤理化分析与坡面描述[M].北京：中国标准出版社,1996：8.
[32]刘光崧.土壤理化分析与剖面描述[M].北京：中国标准出版社,1996：5-7,32.
[33]黄冠华,詹卫华.土壤颗粒的分形特征及其应用[J].土壤学报,2002,39(4)：490-497.
[34]ZHANG J H, LOBB D A, LI Y, et al.Assessment for tillage translocation and tillage erosion by hoeing on the steep land in hilly areas of Sichuan, China[J].Soil Tillage and Research,2004,75:99-107.
[35]蔡强国.黄土高原侵蚀产沙过程与模拟[M].北京：科学出版社.1998：1-150.
[36]张季如,朱瑞赓,祝文化.用粒径的数量分布表征的土壤分形特征[J].水利学报,2004,(4)：1-6.
[37]韩方虎.苜蓿草地土壤氮素矿化的研究[D].兰州：兰州大学,2008.
[38]沈萍,范秀容,李广武.微生物学实验[M].北京：高等教育出版社,1999：92-95.
[39]吴金水,林启美,黄巧云,等.土壤微生物微生物量测定方法及其应用[M].北京：气象出版社,2006：56-60.
[40]鲁如坤.土壤农业化学分析方法[M].北京：中国农业科技出版社,2000.
[41]郭甜,何丙辉,蒋先军,等.紫色土区植物篱对坡面土壤微生物特性的影响[J].水土保持学报,2011,25(5)：94-98,185.
[42]李博.鄂尔多斯高原的自然条件与草地资源概况[A].鄂尔多斯高原沙质灌木草地绒山羊试验区研究所成果汇编[C].呼和浩特：内蒙古教育出版社,1995,1-6.
[43]Jizhong Zhou, Dorothea K. Thompson, Ying Xu et al. Microbial Functional Genomics [M]. A John Wiley & Sons, Inc., Publication, the United States of America,2004,21-40.
[44]巍强,张秋良,代海燕,等.大青山不同林地类型土壤特性及其水源涵养功能[J].水土保持学报,2008,22(2)：111-115.
[45]杨洁,喻荣岗,王照艳,等.红壤侵蚀区优良水土保持草本植物的选择及评价[J].中国水土保持,2009,(3)：25-28.
[46]潘伟彬,邓恢.4种草本水土保持植物的耐旱生理特性[J].华侨大学学报(自然科学版),2009,30(3)：305-308.
[47]成向荣,黄明斌,邵明安,等.紫花苜蓿和短花针茅根系分布与土壤水分研究[J].草地学报,2008,16(2)：170-175.
[48]徐少君,曾波,类淑桐等.三峡库区几种耐水淹植物根系特征与土壤抗水蚀增强效应[J].土壤学报,2011,18(1)：160-165.
[49]韩凤朋,郑纪勇,张兴昌.黄土退耕坡地植物根系分布特征及其对土壤养分的影响[J].农业工程学报,2009,25(2)：50-55.
[50]李勇,张睛雯,李璐,等.黄土区植物根系对营养元素在土壤剖面中迁移强度的影响[J].植物营养与肥料学报,2005,11(4)：427-434.
[51]王燕,王兵,赵广东,等.江西大岗山3种林型土壤水分物理性质研究[J].水土保持学报,2008,22(1)：151-153.
[52]徐艳梅.四种退耕还林(草)模式土壤理化性质及酶活性动态研究[D].雅安：四川农业大学,2007.
[53]王治国,张云龙,刘徐师,等.林业生态工程学：林草植被建设的理论与实践[M].北京：中国林业出版社,2000.
[54]史东梅,陈晏.紫色丘陵区农林混作模式的土壤抗冲性影响因素[J].中国农业科学,2008,41(5)：1400-1409.
[55]陈晏,史东梅,文卓立,等.紫色土丘陵区不同土地利用类型土壤抗冲性特征研究[J].水土保持学报,2007,21(2)：24-27.
[56]陈希哲.土力学地基基础(第4版)[M].北京：清华大学出版社,2004：162-163.
[157]丁军,王兆骞,陈欣,等.红壤丘陵区林地根系对土壤抗冲增强效应的研究[J].水土保持学报,2002,16(4)：9-12.
[158]张建军,张宝颖,毕华兴,等.黄土区不同植被条件下的土壤抗冲性[J].北京林业大学学报,2004,26(6)：25-29.
[159]胡建忠,周心澄,李文忠,等.退耕地青海云杉人工林土壤抗冲性试验研究[J].水土保持学报,2004,18(6)：6-10.