湖南会同退耕还林生态环境效益研究
|
摘要
退耕还林是中国根治水土流失,改善生态环境的根本措施,也是土地利用调整的一种具体措施。本研究从林分生物量、土壤环境效应、养分积累和碳贮量及其空间分布特征、生态效益方面研究湖南会同退耕还林的生态环境效益,可为有关部门进一步完善退耕还林政策提供理论依据和技术支持,对巩固和发展退耕还林工程建设成果,持续开展退耕还林工程建设具有重要意义。主要研究结果如下：
主要造林树种的单株生物量存在一定的差异,但均以地上部分占绝对的优势,占全株生物量的66%以上,各器官生物量的大小排序大致为：树干>树根>树叶>树枝>树皮。杜英×樟树混交林分的生物量最高,为3.916 t·hm-2,樟树纯林的最低,为1.213t·hm-2。4种模式幼林各组分生物量相对分配百分率均表现为：树干(带皮)最大,为32.64%以上,树枝最小,仅为12.65%-17.98%之间。杜英×樟树混交林的平均净生产力最高,为0.4680 t·hm-2·a-1,樟树纯林为其次,杜英×乐昌含笑混交林最低,仅为0.0754t·hm-2·a-1,最高与最低相差0.3926t·hm-2·a-1。
与对照地相比,0-60cm土层中,樟树林地、乐昌含笑×红花木莲混交林地、杜英×樟树混交林地、杜英×乐昌含笑混交林地平均容重下降,平均总孔隙度和平均自然含水率提高,而马尾松林地平均容重提高了14.64%,平均总孔隙度和平均自然含水率分别下降了13.21%、3.48%；马尾松林地、樟树林地、杜英×樟树混交林地、杜英×乐昌含笑混交林地、乐昌含笑×红花木莲混交林地的<0.01mm粘粒百分率分别提高了1.81%、14.99%、13.85%、31.26%、32.38%,1-0.05mm砂粒百分率分别下降了1.48%、13.88%、17.30%、39.78%、22.33%。退耕还林3a后,林地土壤物理性状得到了不同程度的改善,其中乐昌含笑×红花木莲混交林、杜英×乐昌含笑混交林呈现出最明显的改善作用,其次是樟树林和杜英×樟树混交林,马尾松林最弱。
与对照地相比,0-60 cm土层中,pH值除马尾松林地不变外,杜英×乐昌含笑混交林地、乐昌含笑×红花木莲混交林地、樟树林地、杜英×樟树混交林地分别提高了4.30%、3.44%、1.51%、1.29%；乐昌含笑×红花木莲混交林地、杜英×乐昌含笑混交林地、杜英×樟树混交林地、樟树林地有机质平均含量分别提高了53.60%、39.24%、38.63%、24.83%,马尾松林地下降了18.66%；乐昌含笑×红花木莲混交林地、杜英×乐昌含笑混交林地全N平均含量分别提高了61.18%、37.28%,而杜英×樟树混交林地、樟树林地、马尾松林地分别下降了10.38%、14.76%、47.66%；5种模式林地全P平均含量均表现为提高,其中杜英×乐昌含笑混交林地提高幅度最高,为81.75%,马尾松林地提高的幅度最小,为7.94%,全Mg平均含量提高了33.10%以上,全K平均含量均显著下降,下降幅度为43.44%-61.93%之间,全Ca平均含量下降了63.04%以上；杜英×乐昌含笑混交林地、乐昌含笑×红花木莲混交林地平均速效N含量分别提高了21.14%、7.53%,而樟树林地、杜英×樟树混交林地、马尾松林地分别下降了4.41%、9.39%、11.39%,5种模式林地的速效P、速效K平均含量显著提高,提高幅度分别为26.61%-86.85%和120.67%-219.51%之间。5种模式林地土壤微量元素含量变异系数在0.40%-16.40%之间,Zn、Pb、Ni、Cu、Cd的平均含量均未超过中国土壤环境质量标准(GB15618-1995)的Ⅲ级标准值。与对照地相比,在0-60cm土层中,5种模式林地Fe含量均显著下降(P<0.05),Cd平均含量均有相同的下降程度,Cu、Zn、Ni的平均含量却有不同程度的提高；除马尾松林地外,其他4种模式林地Mn的平均含量均显著提高(P<0.05),Pb、Co平均含量也均有所提高。退耕还林3a后,林地土壤pH值、有机质和部分养分元素含量提高,其中乐昌含笑×红花木莲混交林、杜英×乐昌含笑混交林最明显,其次是樟树林和杜英×樟树混交林,马尾松林最弱。
土壤<0.01mm粘粒百分率与土壤自然含水率、pH值、全N、全P、全Mg之间显著正相关,土壤容重与土壤有机质、全P、全N、速效N、速效P、速效K之间显著负相关。退耕还林3a后,林地<0.01mmm粘粒百分率的增加,土壤容重下降,提高土壤涵养水分的能力、土壤pH值和贮存与吸收更多养分。土壤各化学因子之间的关系较为复杂,有的表现为相互促进,有的表现为相互抑制。
以对照地为基准地,马尾松林地、樟树林地、杜英×樟树林混交林地、杜英×乐昌含笑混交林地、乐昌含笑×红花木莲混交林地的综合退化指数分别为-9.33%、18.45%、18.86%、29.33%、21.86%。樟树林、杜英×樟树林混交林、杜英×乐昌含笑混交林、乐昌含笑×红花木莲混交林模式明显地改善林地土壤理化性质,其中杜英×乐昌含笑混交林为最优的配置模式。
种内各器官的灰分平均含量由高至低的排序为：乐昌含笑>红花木莲>樟树>杜英>马尾松,变异系数在38.36%-55.00%之间。树种间同一器官灰分平均含量以树皮的最高,树根为其次,树干最低,变异系数在37.49%-72.31%之间。5种树种各器官N含量最高,K、Ca的含量为其次,P的含量最低。同种营养元素在同一树种不同器官中的含量从高至低的排序大致为：叶>枝>皮>根>干；种间同器官同种营养元素的平均含量基本上也是以叶的含量最高,树枝次之,干的含量最小,变异系数在24.73%-69.16%之间,表明树叶含量最高和树干含量最低是主要造林树种一个基本特征。种内各器官同种营养元素的平均含量不同,马尾松体内各种营养元素含量普遍较低,变异系数在31.35%-110.92%之间。灌木、草本均以N含量最高,K含量次之,灌木P含量普遍最低,草本Mg含量普遍最低。不同生活型植物种间同种营养元素平均含量的排列顺序大致为：草本>灌木>乔木。同一林分下活地被物层的不同营养元素含量从高到低的排序为：N>K>Ca>Mg>P,死地被物层为：N>Ca>K>Mg>P。
马尾松林、樟树林、杜英×樟树混交林、杜英×乐昌含笑混交林、乐昌含笑×红花木莲混交林木中N、P、K、Ca、Mg,总积累量分别为38.090、22.265、37.045、5.974和3.888 kg·hm-2,N、P、K、Ca、Mg积累量的大小排序除马尾松林为N>Ca>K>Mg>P外,其它模式为N>K>Ca>Mg>P;叶中积累量占林木积累量的比例远远超过其生物量占林木生物量的比例。0-60 cm土层中,杜英×乐昌含笑混交林地N、P、K、Ca、Mg总积累量最高,乐昌含笑×红花木莲混交林地和樟树林地次之,马尾松林地最低；与对照地相比,5种模式林地土壤N、P、K、Ca、Mg的总积累量均表现为下降,P、Mg积累量均表现为提高,K、Ca积累量均表现为下降,N积累量因林地不同而异。5种模式幼林生态系统中,土壤层(0～60cm)营养元素贮量最大,占生态系统营养元素总贮量的99%以上,植被层为其次,占0.30%以下,死地被物层为最小
5种树种各器官Fe、Mn含量较高,其次是Cu,而Zn含量较低,种间同器官同种微量元素平均含量的大小排序因元素不同而异,变异系数在11.57%-67.37%之间,种内同种微量元素不同器官平均含量也不同,变异系数在35.63%-89.09%之间,表明不同树种同种器官对同种微量元素的吸收存在较大的差异,即使同一树种不同器官对同种微量元素的吸收也存在明显的差异。灌木、草本中Fe、Mn含量均高于Cu、Zn含量,不同生活型植物种间同种微量元素平均含量的大小排序大致为：草本>灌木>乔木。同一林分下地被物层中不同微量元素含量高低排序均为：Fe>Mn>Cu>Zn。
马尾松林、樟树林、杜英×樟树混交林、杜英×乐昌含笑混交林、乐昌含笑×红花木莲混交林木中微量元素积累量分别为1490.679、679.277、1088.789、202.772和332.781g·hm-2,Cu、Zn、Fe、Mn积累量的大小排序除马尾松林为Mn>Fe>Zn>Cu外,其它模式为Mn>Fe>Cu>Zn,各器官微量元素积累量占林木总积累量的比例基本上随其生物量占总生物量的比例增大而增大。0-60 cm土层中,Cu、Fe、Zn、Mn总积累量马尾松林地最高,樟树林地次之,杜英×樟树混交林地最低,与对照地相比,5种林地Cu、Fe、Zn、Mn总积累量均为下降,各微量元素的积累量从大至小排列均为：Fe>Mn>Zn>Cu, Cu、Zn积累量均为提高,而Fe积累量均下降,Mn除马尾松林地下降外,其它4种模式均为提高。5种模式幼林生态系统中,土层(0-60cm)微量元素贮量最大,占整个生态系统微量元素总积累的99%以上,植被层为其次,约占0.002%,死地被物层为最小。
马尾松、樟树、杜英、乐昌含笑、红花木莲不同器官的平均碳密度分别为：0.5296、0.5188、0.5178、0.5376、0.5355 gC·g-1,种间同器官的平均碳密度排序为：树干>树根>树叶>树枝>树皮；活地被物层、死地被物层碳密度分别介于0.4380-0.5380gC·g-1、0.5060-0.5200gC·g-1之间,土壤层(0-60 cm)平均有机碳密度介于0.00786-0.01485gC·g-1之间；退耕还林3a后,乐昌含笑×红花木莲混交林、杜英×乐昌含笑混交林、杜英×樟树混交林、樟树林土壤层有机碳密度比对照地分别提高了53.57%、39.19%、38.57%、24.82%,而马尾松林地下降了18.72%。林木各器官碳贮量基本上与各器官的生物量成正比例。5种模式幼林生态系统中,土壤层(0-60 cm)碳贮量最大,为74.518-119.312 tC.hm-2,占96.180%以上,植被层为其次,在0.633-2.960tC.hm-2之间,仅占0.642%-3.820%,死地被物层为最小。退耕后,樟树林、杜英×樟树混交林、乐昌含笑×红花木莲混交林、杜英×乐昌含笑混交林生态系统碳贮量分别增加了19.477、27.722、41.643、26.821 tC.hm-2,马尾松林下降了1.675 tC.hm-2。
在保护水资源效益方面,樟树林最高,杜英×樟树混交林地最低；在固C释放02的效益方面,乐昌含笑×红花木莲混交林最高,马尾松林最低,且还呈现为负值。从总的生态效益看来,乐昌含笑×红花木莲混交林最高,达90794.32元.hm-2.a-1,杜英×乐昌含笑混交林为其次,为71471.14元·hm-2·a-1,而马尾松林最低,为9791.88元.hm-2·a-1。表明不同退耕还林模式具有不同的特点和优势,混交林模式优于纯林模式,且以落叶与常绿混交为最优。
The'Grain for Green'program (GGP, i.e., conversion of farmland to florets) was not only a radical measure of elimnating soil erosion and improving ecological environment, but also a concrete measure of regulating lands-use composition in China. Eco-environmental benefit of'Grain for Green'program were investigated by studing biomass, effects on soil environments, nutrient accumulation and carbon storage in young stands within five afforestation patterns (Pinus massoniana pure forests, Cinnamomum camphora pure forests, Elaeocarpus sylvestris and Cinnamomum camphora mixed forests, Michelia chapensis and Manglietia insignis mixed forests, Elaeocarpus sylvestris and Michelia chapensis mixed forests) in Huitong County, Hunan Province, which could provide the significant reference and technical support of further perfecting conversion of farmland to florets policy for the relating administrative department, it was significant to consolidate achievement of the 'Grain for Green'program and sustained spread out the'Grain for Green'program. The main results are as follows:
The biomass of per plant aboveground was absolute superiority in the main tree species, accounting for 66% of total plant biomass, the biomass of organs was essentially in the order as:trunk>root>leaf>branch>bark, there were some differences in biomass of per plant. The sub-biomass of Elaeocarpus sylvestris and Cinnamomum camphora mixed forest was the highest, up to 3.916 t.hm-2, the biomass of Cinnamomum camphora pure forests was the lowest,1.213 t.hm-2. Under four kinds of model for conversion of farmland to forestland, the relative distribution of percentage of each component biomass of young plantation was as follows:trunk (skin) accounted for the largest proportion of forest biomass, for more than 32.64%, the proportion of branch biomass was the smallest, only between 12.65% and 17.98%, the average net productivity of Elaeocarpus sylvestris and Cinnamomum camphora mixed forest was the highest, up to 0.4680 t.hm-2.a-1, Cinnamomum camphora pure was followed, Elaeocarpus sylvestris and Michelia chapensis mixed forest was the lowest, only 0.0754t.hm-2.a-1, the difference between the highest and the lowest was 0.3926t.hm-2.a-1.
Compared with pre-converted farmland in soil layer (0-60cm), the average bulk density was declined, total porosity and natural water content were increased in Cinnamomum camphora pure forests, Michelia chapensis and Manglietia insignis mixed forests, Elaeocarpus sylvestris and Cinnamomum camphora mixed forests, Elaeocarpus sylvestris and Michelia chapensis mixed forests, while the average bulk density in Pinus massoniana pure forests was increased 14.64%, the average total porosity and average natural water content were decreased by 13.21%,3.48%, respectively; the cosmid pecent (<0.01mm) was respectively increased 1.81%,14.99%,13.85%,31.26%,32.38% and the sand pecent (1～0.05mm) was respectively decreased 1.48%,13.88%,17.30%,39.78%,22.33% in Pinus massoniana pure forests, Cinnamomum camphora pure forests, Elaeocarpus sylvestris and Cinnamomum camphora mixed forests, Elaeocarpus sylvestris and Michelia chapensis mixed forests, Michelia chapensis and Manglietia insignis mixed forests. Soil physical conditions had been improved in different degrees, in which the modification of Michelia chapensis and Manglietia insignis mixed forests, Elaeocarpus sylvestris and Michelia chapensis mixed forests showed the most significant, followed by Cinnamomum camphora pure forests, Elaeocarpus sylvestris and Cinnamomum camphora mixed forests, that of Pinus massoniana pure forests was the worst.
Compared with pre-converted farmland in soil layer (0-60cm), pH respectively was increased 4.30%,3.44%,1.51%,1.29% in Elaeocarpus sylvestris and Michelia chapensis mixed forests, Michelia chapensis and Manglietia insignis mixed forests, Cinnamomum camphora pure forests, Elaeocarpus sylvestris and Cinnamomum camphora mixed forests, while unchanged in Pinus massoniana pure forests. Average content of soil organic matter respectively was increased 53.60%,39.24%,38.63%,24.83% in Michelia chapensis and Manglietia insignis mixed forests, Elaeocarpus sylvestris and Michelia chapensis mixed forests, Elaeocarpus sylvestris and Cinnamomum camphora mixed forests, Cinnamomum camphora pure forests, but was decreased by 18.66% in Pinus massoniana pure forests. Average content of N respectively was increased 61.18%,37.28% in Michelia chapensis and Manglietia insignis mixed forests and Elaeocarpus sylvestris and Michelia chapensis mixed forests, but respectively was decreased 10.38%,14.78%,47.66% in Elaeocarpus sylvestris and Cinnamomum camphora mixed forests, Cinnamomum camphora pure forests, Pinus massoniana pure forests. Average content of P improved in five model forests, of which the highest rate of Elaeocarpus sylvestris and Cinnamomum camphora mixed forests was 57%, and Pinus massoniana pure forests was the lowest,7.94%; the average content of Mg increased more than 33.10%, the average content of K was decreased significantly 3.44% to 61.93%, the average content of Ca was decreased more than 63.04%. Average content of available N respectively was increased 21.14%,7.53% in Elaeocarpus sylvestris and Michelia chapensis mixed forests, Michelia chapensis and Manglietia insignis mixed forests, while was decreased 4.41%,9.39%,11.39% in Cinnamomum camphora pure forests, Elaeocarpus sylvestris and Cinnamomum camphora mixed forests, Pinus massoniana pure forests. The average content of available P and available K obviously was increased 26.61% to 86.85% and 120.67% to 219.51% respectively in five model forest. Soil microelement content's coefficient of variation of the five forests were in 0.40% to 16.40%, and the average content of Zn, Pb, Ni, Cu, Cd were both in the third rank of GB15618-1995. Compared with pre-converted farmland in soil layer (0-60cm), in the five forests, Fe obviously was increased (p<0.05), but Cd was decreased in same level, Cu, Zn, Ni was increased in different level. Expect in Pinus massoniana pure forests, Mn obviously was increased (p<0.05) in another afforestation model, Pb, Co was increased in some level, three years after the conversion of farmland to forests, pH, soil organic matter and part of nutrition elements were increased. Michelia chapensis and Manglietia insignis mixed forests, Elaeocarpus sylvestris and Michelia chapensis mixed forests had the most obviously change, the second were Cinnamomum camphora pure forests, Elaeocarpus sylvestrisand Cinnamomum camphora mixed forests, the last was Pinus massoniana pure forests.
The significant positive correlation appears between the cosmid pecent(<0.01mm) and soil natural water content rate, pH, N, P, Mg; while the significant negative correlation appears between soil bulk density and soil organic matter, P, N, available N, available P, available K. Three years after the conversion of farmland to forests, the cosmid pecent (<0.01mm) increased and soil bulk density decreased, the ability of water conservation, pH, nutrient storage and absorption were increased. The ralationship among each chemical factor was very complex, some showed promote each other, but some showed inhibition each other.
Assume that farmland was the standard, composite degradation index of Pinus massoniana pure forests, Cinnamomum camphora pure forests, Elaeocarpus sylvestris and Cinnamomum camphora mixed forests, Elaeocarpus sylvestris and Michelia chapensis mixed forests and Michelia chapensis and Manglietia insignis mixed forests were-9.33%, 18.45%,18.86%,29.33%,21.86%, respectively. All of them except Pinus massoniana pure forests could improve soil properties, Elaeocarpus sylvestris and Michelia chapensis mixed forests did it best in the four.
The order of the average content of ash in different organs of the same tree was as follow:Michelia chapensis> Manglietia insignis> Cinnamomum camphora> Elaeocarpus sylvestris> Pinus massoniana and the coefficient of variation is between 38.36% and 55.00%. The average content of ash in the barks of different trees was the highest, the second was roots, the lowest was trunks, and the coefficient of variation was from 37.49% to72.31%. N concent was the highest in different organs of 5 kind's trees, K and Ca was the second, the lowest was P. The order of same nutrient concent in same tree's different organs from high to low roughly was as follows:leaf> branch> bark> root> stem. The highest nutrient average content of the same nutrient in 5 kind's trees'same organ was leaves, the second was branches and the smallest was stem. Coefficient of variation was from 24.73% to 69.16%. The result showed that the highest leaves and lowest stem content was a basic feature of major afforestation trees. The average nutrient concent of different organs in the same tree was different; the nutrient concents of Pinus massoniana were generally low. The coefficients of variation were between 31.35% and 110.92%. N was the highest in Shrubs and herbs, K was the second, P was generally the lowest in shrub and Mg was generally the lowest in herb. The order of average content of nutrients between different species life ranked as:herbs>shrubs>frees. The different of nutrient content of living sort under the same stand from high to low was as follow:N> K>Ca>Mg>P, that of the dead litter layer:N>Ca>K>Mg>P.
The total amount of nutrient elements of N, P, K, Ca, Mg were 38.090,22.265,37.045, 5.974 and 3.888 kg-hm-2 in five different forests of Pinus massoniana pure forests, Cinnamomum camphora pure forests, Elaeocarpus sylvestris and Cinnamomum camphora mixed forests, Michelia chapensis and Manglietia insignis mixed forests, Elaeocarpus sylvestris and Michelia chapensis mixed forests. The amount of accumulation presents was N>Ca>K>Mg>P in Pinus massoniana pure forests and N>K>Ca>Mg>P in another four different forests, which the proportion of leaf accumulation in tree accumulation were farther outweight than the proportion of biomass in tree biomass. The total amount of N, P, K, Ca, Mg in accumulation of 0-60cm soil layer of Elaeocarpus sylvestris and Michelia chapensis mixed forests was the highest. Michelia chapensis and Manglietia insignis mixed forests, Cinnamomum camphora pure forests took the second place, Pinus massoniana pure forests was the end. Compared with pre-converted farmland, the total amount of N, P, K, Ca, and Mg in soil decreased in five different forests. At the same time, the accumulation P, Mg increased and K, Ca decreased, but N presented different in different forests. In these five modle of young ecosystems, the nutrient elements capacity in 0-60cm soil was the highest, which accounted for more than 99% of the total capacity in nutrient elements of ecological system. Vegetation layer took the second place, less than 0.30%, and the dead vegetation layer was the least.
Content of Fe, Mn was the firstly higher in different organs of the 5 species trees, Cu was the secondly, Zn was the lower, the order of the same microelements concent in the same organs of different species showed different with different microelements, coefficients of variation of microelements in different species were in range of 11.57% to 67.73%, concent of the same microelements of different organ in the same species were also different, coefficients of variation were in range of 35.63% to 89.09%. The results showed that it was more different for the same organs in different species to have different absorptive capacity to the same trace elements, even though different organs in the same species to have different absorptive capacity to the same trace element. Concent of Fe, Mn was higher than that of Cu and Zn in bush and herbal, the order of concent of the same trace elements in different life form species ranked as follow:herbal>bush>arbor. Content of different trace elements of the ground cover in same forest type was in the order as:Fe>Mn>Cu>Zn.
The total amount of trace elements were 1490.679,679.277,1088.789,202.772 and 332.781 g·hm-2 in Pinus massoniana pure forests, Cinnamomum camphora pure forests, Elaeocarpus sylvestris and Cinnamomum camphora mixed forests, Elaeocarpus sylvestris and Michelia chapensis mixed forests, Michelia chapensis and Manglietia insignis mixed forests, respectively. The amount of accumulation presents was Mn>Fe>Zn>Cu in Pinus massoniana pure forests and other four different forests were Mn>Fe>Cu>Zn, the proportionment of trace elements accumulation in different organs was positively related to the biomass of these respective organs. In 0-60cm layer soil, Pinus massoniana pure forests showed the highest content of Cu, Fe, Zn, Mn, Cinnamomum camphora pure forests was the second, the last was Elaeocarpus sylvestris and Cinnamomum camphora mixed forests. Compared with the control, Cu, Fe, Zn, Mn total accumulation were all decreased. The order of accumulation of trace elements was in Fe> Mn> Zn> Cu. Accumulation were increased with Cu, Zn and decreased with Fe. Mn was incresed except in Pinus massoniana pure forests. In these five modle of young ecosystems, the trace elements capacity in 0-60cm soil was the highest, accounted for more than 99% of the total capacity in trace elements of ecological system, vegetation layer took the second place, was up to 0.002%, and dead vegetation layer was the least.
The mean carbon densities of all organs were 0.5296,0.5188,0.5178,0.5376, and 0.5355 gC·g-1 for the tree species Pinus massoniana, Cinnamomum camphora, Elaeocarpus sylvestris, Michelia chapensis, and Manglietia insignis, respectively. The average carbon densities in different organs of the five tree species ranked in the order as:trunk>root>leaf >branch>bark. Carbon densities ranged from 0.4380 to 0.5380gC·g-1,0.5060 to0.5200gC·g-1 and 0.00786 to 0.01485 gC·g-1 in living-understory layer, litterfall layer and soil layer (0～60 cm depth), respectively within the five afforestation patterns. Three years later after the conversion of farmland to forests, soil organic carbon density was increased 53.6%,39.2%, 38.6%, and 24.8% in Michelia chapensis and Manglietia insignis mixed forests, Elaeocarpus sylvestris and Michelia chapensis mixed forests, Elaeocarpus sylvestris and Cinnamomum camphora mixed forests and Cinnamomum camphora forests, but decreased 18.7% in Pinus massoniana forest when compared with pre-converted farmland. Carbon storage in different organs was positively related to the biomass of these respective organs. It was found that Elaeocarpus sylvestris and Cinnamomum camphora mixed forest had the highest carbon stocks in the tree biomass pools (1.22 tC·hm-2), while Elaeocarpus sylvestris and Michelia chapensis mixed forest had the lowest value (0.20 tC·hm-2). Trunk and root stored more carbon than other organs, and the two organs accounted for 57.5% of the total carbon storage in all tree organs. At the early stage of the five forested ecosystems, the soil layer (0～60 cm) had the largest carbon storage, ranging from 74.52 to119.31 tC-hm-2, and accounted for more than 96.2% of the total carbon storage in the ecosystems. Carbon storage in the plant layer ranged from 0.63 to 2.96 tC-hm-2, which accounted for 0.64 to 3.8% of the total carbon storage of the ecosystems. The litter fall layer had the smallest proportion of the carbon storage within the ecosystems. After conversion of farmland to forestland, the carbon storage was increased 19.48,27.72,41.64,26.82 tC·hm-2 in Cinnamomum camphora pure forests, Cinnamomum camphora and Elaeocarpus sylvestris mixed forests, Michelia chapensis and Manglietia insignis mixed forests, Elaeocarpus sylvestris and Michelia chapensis mixed forests, respectively, but decreased 1.68 tC·hm-2 in Pinus massoniana pure forests. Our results indicated that'Grain for Green' program, especially in the patterns of farmland to mixed forests, had great potential to enhance carbon sequestration in terrestrial ecosystems of southern China.
Cinnamomum camphora pure forests was the most effective in the protection of water resources effectiveness, Elaeocarpus sylvestris and Cinnamomum camphora mixed forests was the worst; Michelia chapensis and Manglietia insignis mixed forests was the most effective for the release of O2 in solid C's effectiveness, Pinus massoniana pure forests was the worst, even showed negative. Michelia chapensis and Manglietia insignis mixed forests was the highest for ecology efficiency, was up to 90794.32 yuan-hm-2·a-1, the second was Elaeocarpus sylvestris and Michelia chapensis mixed forests, up to 71471.14 yuan-hm-2·a-1; the last was Pinus massoniana pure forests, only 9791.88 yuan-hm-2·a-1. It showed that different modle of 'Grain for Green' had different characteristic and advantages, mix forests were better than singleness forest and the mix forests with hardwood and evergreen was the best.
主要造林树种的单株生物量存在一定的差异,但均以地上部分占绝对的优势,占全株生物量的66%以上,各器官生物量的大小排序大致为：树干>树根>树叶>树枝>树皮。杜英×樟树混交林分的生物量最高,为3.916 t·hm-2,樟树纯林的最低,为1.213t·hm-2。4种模式幼林各组分生物量相对分配百分率均表现为：树干(带皮)最大,为32.64%以上,树枝最小,仅为12.65%-17.98%之间。杜英×樟树混交林的平均净生产力最高,为0.4680 t·hm-2·a-1,樟树纯林为其次,杜英×乐昌含笑混交林最低,仅为0.0754t·hm-2·a-1,最高与最低相差0.3926t·hm-2·a-1。
与对照地相比,0-60cm土层中,樟树林地、乐昌含笑×红花木莲混交林地、杜英×樟树混交林地、杜英×乐昌含笑混交林地平均容重下降,平均总孔隙度和平均自然含水率提高,而马尾松林地平均容重提高了14.64%,平均总孔隙度和平均自然含水率分别下降了13.21%、3.48%；马尾松林地、樟树林地、杜英×樟树混交林地、杜英×乐昌含笑混交林地、乐昌含笑×红花木莲混交林地的<0.01mm粘粒百分率分别提高了1.81%、14.99%、13.85%、31.26%、32.38%,1-0.05mm砂粒百分率分别下降了1.48%、13.88%、17.30%、39.78%、22.33%。退耕还林3a后,林地土壤物理性状得到了不同程度的改善,其中乐昌含笑×红花木莲混交林、杜英×乐昌含笑混交林呈现出最明显的改善作用,其次是樟树林和杜英×樟树混交林,马尾松林最弱。
与对照地相比,0-60 cm土层中,pH值除马尾松林地不变外,杜英×乐昌含笑混交林地、乐昌含笑×红花木莲混交林地、樟树林地、杜英×樟树混交林地分别提高了4.30%、3.44%、1.51%、1.29%；乐昌含笑×红花木莲混交林地、杜英×乐昌含笑混交林地、杜英×樟树混交林地、樟树林地有机质平均含量分别提高了53.60%、39.24%、38.63%、24.83%,马尾松林地下降了18.66%；乐昌含笑×红花木莲混交林地、杜英×乐昌含笑混交林地全N平均含量分别提高了61.18%、37.28%,而杜英×樟树混交林地、樟树林地、马尾松林地分别下降了10.38%、14.76%、47.66%；5种模式林地全P平均含量均表现为提高,其中杜英×乐昌含笑混交林地提高幅度最高,为81.75%,马尾松林地提高的幅度最小,为7.94%,全Mg平均含量提高了33.10%以上,全K平均含量均显著下降,下降幅度为43.44%-61.93%之间,全Ca平均含量下降了63.04%以上；杜英×乐昌含笑混交林地、乐昌含笑×红花木莲混交林地平均速效N含量分别提高了21.14%、7.53%,而樟树林地、杜英×樟树混交林地、马尾松林地分别下降了4.41%、9.39%、11.39%,5种模式林地的速效P、速效K平均含量显著提高,提高幅度分别为26.61%-86.85%和120.67%-219.51%之间。5种模式林地土壤微量元素含量变异系数在0.40%-16.40%之间,Zn、Pb、Ni、Cu、Cd的平均含量均未超过中国土壤环境质量标准(GB15618-1995)的Ⅲ级标准值。与对照地相比,在0-60cm土层中,5种模式林地Fe含量均显著下降(P<0.05),Cd平均含量均有相同的下降程度,Cu、Zn、Ni的平均含量却有不同程度的提高；除马尾松林地外,其他4种模式林地Mn的平均含量均显著提高(P<0.05),Pb、Co平均含量也均有所提高。退耕还林3a后,林地土壤pH值、有机质和部分养分元素含量提高,其中乐昌含笑×红花木莲混交林、杜英×乐昌含笑混交林最明显,其次是樟树林和杜英×樟树混交林,马尾松林最弱。
土壤<0.01mm粘粒百分率与土壤自然含水率、pH值、全N、全P、全Mg之间显著正相关,土壤容重与土壤有机质、全P、全N、速效N、速效P、速效K之间显著负相关。退耕还林3a后,林地<0.01mmm粘粒百分率的增加,土壤容重下降,提高土壤涵养水分的能力、土壤pH值和贮存与吸收更多养分。土壤各化学因子之间的关系较为复杂,有的表现为相互促进,有的表现为相互抑制。
以对照地为基准地,马尾松林地、樟树林地、杜英×樟树林混交林地、杜英×乐昌含笑混交林地、乐昌含笑×红花木莲混交林地的综合退化指数分别为-9.33%、18.45%、18.86%、29.33%、21.86%。樟树林、杜英×樟树林混交林、杜英×乐昌含笑混交林、乐昌含笑×红花木莲混交林模式明显地改善林地土壤理化性质,其中杜英×乐昌含笑混交林为最优的配置模式。
种内各器官的灰分平均含量由高至低的排序为：乐昌含笑>红花木莲>樟树>杜英>马尾松,变异系数在38.36%-55.00%之间。树种间同一器官灰分平均含量以树皮的最高,树根为其次,树干最低,变异系数在37.49%-72.31%之间。5种树种各器官N含量最高,K、Ca的含量为其次,P的含量最低。同种营养元素在同一树种不同器官中的含量从高至低的排序大致为：叶>枝>皮>根>干；种间同器官同种营养元素的平均含量基本上也是以叶的含量最高,树枝次之,干的含量最小,变异系数在24.73%-69.16%之间,表明树叶含量最高和树干含量最低是主要造林树种一个基本特征。种内各器官同种营养元素的平均含量不同,马尾松体内各种营养元素含量普遍较低,变异系数在31.35%-110.92%之间。灌木、草本均以N含量最高,K含量次之,灌木P含量普遍最低,草本Mg含量普遍最低。不同生活型植物种间同种营养元素平均含量的排列顺序大致为：草本>灌木>乔木。同一林分下活地被物层的不同营养元素含量从高到低的排序为：N>K>Ca>Mg>P,死地被物层为：N>Ca>K>Mg>P。
马尾松林、樟树林、杜英×樟树混交林、杜英×乐昌含笑混交林、乐昌含笑×红花木莲混交林木中N、P、K、Ca、Mg,总积累量分别为38.090、22.265、37.045、5.974和3.888 kg·hm-2,N、P、K、Ca、Mg积累量的大小排序除马尾松林为N>Ca>K>Mg>P外,其它模式为N>K>Ca>Mg>P;叶中积累量占林木积累量的比例远远超过其生物量占林木生物量的比例。0-60 cm土层中,杜英×乐昌含笑混交林地N、P、K、Ca、Mg总积累量最高,乐昌含笑×红花木莲混交林地和樟树林地次之,马尾松林地最低；与对照地相比,5种模式林地土壤N、P、K、Ca、Mg的总积累量均表现为下降,P、Mg积累量均表现为提高,K、Ca积累量均表现为下降,N积累量因林地不同而异。5种模式幼林生态系统中,土壤层(0～60cm)营养元素贮量最大,占生态系统营养元素总贮量的99%以上,植被层为其次,占0.30%以下,死地被物层为最小
5种树种各器官Fe、Mn含量较高,其次是Cu,而Zn含量较低,种间同器官同种微量元素平均含量的大小排序因元素不同而异,变异系数在11.57%-67.37%之间,种内同种微量元素不同器官平均含量也不同,变异系数在35.63%-89.09%之间,表明不同树种同种器官对同种微量元素的吸收存在较大的差异,即使同一树种不同器官对同种微量元素的吸收也存在明显的差异。灌木、草本中Fe、Mn含量均高于Cu、Zn含量,不同生活型植物种间同种微量元素平均含量的大小排序大致为：草本>灌木>乔木。同一林分下地被物层中不同微量元素含量高低排序均为：Fe>Mn>Cu>Zn。
马尾松林、樟树林、杜英×樟树混交林、杜英×乐昌含笑混交林、乐昌含笑×红花木莲混交林木中微量元素积累量分别为1490.679、679.277、1088.789、202.772和332.781g·hm-2,Cu、Zn、Fe、Mn积累量的大小排序除马尾松林为Mn>Fe>Zn>Cu外,其它模式为Mn>Fe>Cu>Zn,各器官微量元素积累量占林木总积累量的比例基本上随其生物量占总生物量的比例增大而增大。0-60 cm土层中,Cu、Fe、Zn、Mn总积累量马尾松林地最高,樟树林地次之,杜英×樟树混交林地最低,与对照地相比,5种林地Cu、Fe、Zn、Mn总积累量均为下降,各微量元素的积累量从大至小排列均为：Fe>Mn>Zn>Cu, Cu、Zn积累量均为提高,而Fe积累量均下降,Mn除马尾松林地下降外,其它4种模式均为提高。5种模式幼林生态系统中,土层(0-60cm)微量元素贮量最大,占整个生态系统微量元素总积累的99%以上,植被层为其次,约占0.002%,死地被物层为最小。
马尾松、樟树、杜英、乐昌含笑、红花木莲不同器官的平均碳密度分别为：0.5296、0.5188、0.5178、0.5376、0.5355 gC·g-1,种间同器官的平均碳密度排序为：树干>树根>树叶>树枝>树皮；活地被物层、死地被物层碳密度分别介于0.4380-0.5380gC·g-1、0.5060-0.5200gC·g-1之间,土壤层(0-60 cm)平均有机碳密度介于0.00786-0.01485gC·g-1之间；退耕还林3a后,乐昌含笑×红花木莲混交林、杜英×乐昌含笑混交林、杜英×樟树混交林、樟树林土壤层有机碳密度比对照地分别提高了53.57%、39.19%、38.57%、24.82%,而马尾松林地下降了18.72%。林木各器官碳贮量基本上与各器官的生物量成正比例。5种模式幼林生态系统中,土壤层(0-60 cm)碳贮量最大,为74.518-119.312 tC.hm-2,占96.180%以上,植被层为其次,在0.633-2.960tC.hm-2之间,仅占0.642%-3.820%,死地被物层为最小。退耕后,樟树林、杜英×樟树混交林、乐昌含笑×红花木莲混交林、杜英×乐昌含笑混交林生态系统碳贮量分别增加了19.477、27.722、41.643、26.821 tC.hm-2,马尾松林下降了1.675 tC.hm-2。
在保护水资源效益方面,樟树林最高,杜英×樟树混交林地最低；在固C释放02的效益方面,乐昌含笑×红花木莲混交林最高,马尾松林最低,且还呈现为负值。从总的生态效益看来,乐昌含笑×红花木莲混交林最高,达90794.32元.hm-2.a-1,杜英×乐昌含笑混交林为其次,为71471.14元·hm-2·a-1,而马尾松林最低,为9791.88元.hm-2·a-1。表明不同退耕还林模式具有不同的特点和优势,混交林模式优于纯林模式,且以落叶与常绿混交为最优。
The'Grain for Green'program (GGP, i.e., conversion of farmland to florets) was not only a radical measure of elimnating soil erosion and improving ecological environment, but also a concrete measure of regulating lands-use composition in China. Eco-environmental benefit of'Grain for Green'program were investigated by studing biomass, effects on soil environments, nutrient accumulation and carbon storage in young stands within five afforestation patterns (Pinus massoniana pure forests, Cinnamomum camphora pure forests, Elaeocarpus sylvestris and Cinnamomum camphora mixed forests, Michelia chapensis and Manglietia insignis mixed forests, Elaeocarpus sylvestris and Michelia chapensis mixed forests) in Huitong County, Hunan Province, which could provide the significant reference and technical support of further perfecting conversion of farmland to florets policy for the relating administrative department, it was significant to consolidate achievement of the 'Grain for Green'program and sustained spread out the'Grain for Green'program. The main results are as follows:
The biomass of per plant aboveground was absolute superiority in the main tree species, accounting for 66% of total plant biomass, the biomass of organs was essentially in the order as:trunk>root>leaf>branch>bark, there were some differences in biomass of per plant. The sub-biomass of Elaeocarpus sylvestris and Cinnamomum camphora mixed forest was the highest, up to 3.916 t.hm-2, the biomass of Cinnamomum camphora pure forests was the lowest,1.213 t.hm-2. Under four kinds of model for conversion of farmland to forestland, the relative distribution of percentage of each component biomass of young plantation was as follows:trunk (skin) accounted for the largest proportion of forest biomass, for more than 32.64%, the proportion of branch biomass was the smallest, only between 12.65% and 17.98%, the average net productivity of Elaeocarpus sylvestris and Cinnamomum camphora mixed forest was the highest, up to 0.4680 t.hm-2.a-1, Cinnamomum camphora pure was followed, Elaeocarpus sylvestris and Michelia chapensis mixed forest was the lowest, only 0.0754t.hm-2.a-1, the difference between the highest and the lowest was 0.3926t.hm-2.a-1.
Compared with pre-converted farmland in soil layer (0-60cm), the average bulk density was declined, total porosity and natural water content were increased in Cinnamomum camphora pure forests, Michelia chapensis and Manglietia insignis mixed forests, Elaeocarpus sylvestris and Cinnamomum camphora mixed forests, Elaeocarpus sylvestris and Michelia chapensis mixed forests, while the average bulk density in Pinus massoniana pure forests was increased 14.64%, the average total porosity and average natural water content were decreased by 13.21%,3.48%, respectively; the cosmid pecent (<0.01mm) was respectively increased 1.81%,14.99%,13.85%,31.26%,32.38% and the sand pecent (1～0.05mm) was respectively decreased 1.48%,13.88%,17.30%,39.78%,22.33% in Pinus massoniana pure forests, Cinnamomum camphora pure forests, Elaeocarpus sylvestris and Cinnamomum camphora mixed forests, Elaeocarpus sylvestris and Michelia chapensis mixed forests, Michelia chapensis and Manglietia insignis mixed forests. Soil physical conditions had been improved in different degrees, in which the modification of Michelia chapensis and Manglietia insignis mixed forests, Elaeocarpus sylvestris and Michelia chapensis mixed forests showed the most significant, followed by Cinnamomum camphora pure forests, Elaeocarpus sylvestris and Cinnamomum camphora mixed forests, that of Pinus massoniana pure forests was the worst.
Compared with pre-converted farmland in soil layer (0-60cm), pH respectively was increased 4.30%,3.44%,1.51%,1.29% in Elaeocarpus sylvestris and Michelia chapensis mixed forests, Michelia chapensis and Manglietia insignis mixed forests, Cinnamomum camphora pure forests, Elaeocarpus sylvestris and Cinnamomum camphora mixed forests, while unchanged in Pinus massoniana pure forests. Average content of soil organic matter respectively was increased 53.60%,39.24%,38.63%,24.83% in Michelia chapensis and Manglietia insignis mixed forests, Elaeocarpus sylvestris and Michelia chapensis mixed forests, Elaeocarpus sylvestris and Cinnamomum camphora mixed forests, Cinnamomum camphora pure forests, but was decreased by 18.66% in Pinus massoniana pure forests. Average content of N respectively was increased 61.18%,37.28% in Michelia chapensis and Manglietia insignis mixed forests and Elaeocarpus sylvestris and Michelia chapensis mixed forests, but respectively was decreased 10.38%,14.78%,47.66% in Elaeocarpus sylvestris and Cinnamomum camphora mixed forests, Cinnamomum camphora pure forests, Pinus massoniana pure forests. Average content of P improved in five model forests, of which the highest rate of Elaeocarpus sylvestris and Cinnamomum camphora mixed forests was 57%, and Pinus massoniana pure forests was the lowest,7.94%; the average content of Mg increased more than 33.10%, the average content of K was decreased significantly 3.44% to 61.93%, the average content of Ca was decreased more than 63.04%. Average content of available N respectively was increased 21.14%,7.53% in Elaeocarpus sylvestris and Michelia chapensis mixed forests, Michelia chapensis and Manglietia insignis mixed forests, while was decreased 4.41%,9.39%,11.39% in Cinnamomum camphora pure forests, Elaeocarpus sylvestris and Cinnamomum camphora mixed forests, Pinus massoniana pure forests. The average content of available P and available K obviously was increased 26.61% to 86.85% and 120.67% to 219.51% respectively in five model forest. Soil microelement content's coefficient of variation of the five forests were in 0.40% to 16.40%, and the average content of Zn, Pb, Ni, Cu, Cd were both in the third rank of GB15618-1995. Compared with pre-converted farmland in soil layer (0-60cm), in the five forests, Fe obviously was increased (p<0.05), but Cd was decreased in same level, Cu, Zn, Ni was increased in different level. Expect in Pinus massoniana pure forests, Mn obviously was increased (p<0.05) in another afforestation model, Pb, Co was increased in some level, three years after the conversion of farmland to forests, pH, soil organic matter and part of nutrition elements were increased. Michelia chapensis and Manglietia insignis mixed forests, Elaeocarpus sylvestris and Michelia chapensis mixed forests had the most obviously change, the second were Cinnamomum camphora pure forests, Elaeocarpus sylvestrisand Cinnamomum camphora mixed forests, the last was Pinus massoniana pure forests.
The significant positive correlation appears between the cosmid pecent(<0.01mm) and soil natural water content rate, pH, N, P, Mg; while the significant negative correlation appears between soil bulk density and soil organic matter, P, N, available N, available P, available K. Three years after the conversion of farmland to forests, the cosmid pecent (<0.01mm) increased and soil bulk density decreased, the ability of water conservation, pH, nutrient storage and absorption were increased. The ralationship among each chemical factor was very complex, some showed promote each other, but some showed inhibition each other.
Assume that farmland was the standard, composite degradation index of Pinus massoniana pure forests, Cinnamomum camphora pure forests, Elaeocarpus sylvestris and Cinnamomum camphora mixed forests, Elaeocarpus sylvestris and Michelia chapensis mixed forests and Michelia chapensis and Manglietia insignis mixed forests were-9.33%, 18.45%,18.86%,29.33%,21.86%, respectively. All of them except Pinus massoniana pure forests could improve soil properties, Elaeocarpus sylvestris and Michelia chapensis mixed forests did it best in the four.
The order of the average content of ash in different organs of the same tree was as follow:Michelia chapensis> Manglietia insignis> Cinnamomum camphora> Elaeocarpus sylvestris> Pinus massoniana and the coefficient of variation is between 38.36% and 55.00%. The average content of ash in the barks of different trees was the highest, the second was roots, the lowest was trunks, and the coefficient of variation was from 37.49% to72.31%. N concent was the highest in different organs of 5 kind's trees, K and Ca was the second, the lowest was P. The order of same nutrient concent in same tree's different organs from high to low roughly was as follows:leaf> branch> bark> root> stem. The highest nutrient average content of the same nutrient in 5 kind's trees'same organ was leaves, the second was branches and the smallest was stem. Coefficient of variation was from 24.73% to 69.16%. The result showed that the highest leaves and lowest stem content was a basic feature of major afforestation trees. The average nutrient concent of different organs in the same tree was different; the nutrient concents of Pinus massoniana were generally low. The coefficients of variation were between 31.35% and 110.92%. N was the highest in Shrubs and herbs, K was the second, P was generally the lowest in shrub and Mg was generally the lowest in herb. The order of average content of nutrients between different species life ranked as:herbs>shrubs>frees. The different of nutrient content of living sort under the same stand from high to low was as follow:N> K>Ca>Mg>P, that of the dead litter layer:N>Ca>K>Mg>P.
The total amount of nutrient elements of N, P, K, Ca, Mg were 38.090,22.265,37.045, 5.974 and 3.888 kg-hm-2 in five different forests of Pinus massoniana pure forests, Cinnamomum camphora pure forests, Elaeocarpus sylvestris and Cinnamomum camphora mixed forests, Michelia chapensis and Manglietia insignis mixed forests, Elaeocarpus sylvestris and Michelia chapensis mixed forests. The amount of accumulation presents was N>Ca>K>Mg>P in Pinus massoniana pure forests and N>K>Ca>Mg>P in another four different forests, which the proportion of leaf accumulation in tree accumulation were farther outweight than the proportion of biomass in tree biomass. The total amount of N, P, K, Ca, Mg in accumulation of 0-60cm soil layer of Elaeocarpus sylvestris and Michelia chapensis mixed forests was the highest. Michelia chapensis and Manglietia insignis mixed forests, Cinnamomum camphora pure forests took the second place, Pinus massoniana pure forests was the end. Compared with pre-converted farmland, the total amount of N, P, K, Ca, and Mg in soil decreased in five different forests. At the same time, the accumulation P, Mg increased and K, Ca decreased, but N presented different in different forests. In these five modle of young ecosystems, the nutrient elements capacity in 0-60cm soil was the highest, which accounted for more than 99% of the total capacity in nutrient elements of ecological system. Vegetation layer took the second place, less than 0.30%, and the dead vegetation layer was the least.
Content of Fe, Mn was the firstly higher in different organs of the 5 species trees, Cu was the secondly, Zn was the lower, the order of the same microelements concent in the same organs of different species showed different with different microelements, coefficients of variation of microelements in different species were in range of 11.57% to 67.73%, concent of the same microelements of different organ in the same species were also different, coefficients of variation were in range of 35.63% to 89.09%. The results showed that it was more different for the same organs in different species to have different absorptive capacity to the same trace elements, even though different organs in the same species to have different absorptive capacity to the same trace element. Concent of Fe, Mn was higher than that of Cu and Zn in bush and herbal, the order of concent of the same trace elements in different life form species ranked as follow:herbal>bush>arbor. Content of different trace elements of the ground cover in same forest type was in the order as:Fe>Mn>Cu>Zn.
The total amount of trace elements were 1490.679,679.277,1088.789,202.772 and 332.781 g·hm-2 in Pinus massoniana pure forests, Cinnamomum camphora pure forests, Elaeocarpus sylvestris and Cinnamomum camphora mixed forests, Elaeocarpus sylvestris and Michelia chapensis mixed forests, Michelia chapensis and Manglietia insignis mixed forests, respectively. The amount of accumulation presents was Mn>Fe>Zn>Cu in Pinus massoniana pure forests and other four different forests were Mn>Fe>Cu>Zn, the proportionment of trace elements accumulation in different organs was positively related to the biomass of these respective organs. In 0-60cm layer soil, Pinus massoniana pure forests showed the highest content of Cu, Fe, Zn, Mn, Cinnamomum camphora pure forests was the second, the last was Elaeocarpus sylvestris and Cinnamomum camphora mixed forests. Compared with the control, Cu, Fe, Zn, Mn total accumulation were all decreased. The order of accumulation of trace elements was in Fe> Mn> Zn> Cu. Accumulation were increased with Cu, Zn and decreased with Fe. Mn was incresed except in Pinus massoniana pure forests. In these five modle of young ecosystems, the trace elements capacity in 0-60cm soil was the highest, accounted for more than 99% of the total capacity in trace elements of ecological system, vegetation layer took the second place, was up to 0.002%, and dead vegetation layer was the least.
The mean carbon densities of all organs were 0.5296,0.5188,0.5178,0.5376, and 0.5355 gC·g-1 for the tree species Pinus massoniana, Cinnamomum camphora, Elaeocarpus sylvestris, Michelia chapensis, and Manglietia insignis, respectively. The average carbon densities in different organs of the five tree species ranked in the order as:trunk>root>leaf >branch>bark. Carbon densities ranged from 0.4380 to 0.5380gC·g-1,0.5060 to0.5200gC·g-1 and 0.00786 to 0.01485 gC·g-1 in living-understory layer, litterfall layer and soil layer (0～60 cm depth), respectively within the five afforestation patterns. Three years later after the conversion of farmland to forests, soil organic carbon density was increased 53.6%,39.2%, 38.6%, and 24.8% in Michelia chapensis and Manglietia insignis mixed forests, Elaeocarpus sylvestris and Michelia chapensis mixed forests, Elaeocarpus sylvestris and Cinnamomum camphora mixed forests and Cinnamomum camphora forests, but decreased 18.7% in Pinus massoniana forest when compared with pre-converted farmland. Carbon storage in different organs was positively related to the biomass of these respective organs. It was found that Elaeocarpus sylvestris and Cinnamomum camphora mixed forest had the highest carbon stocks in the tree biomass pools (1.22 tC·hm-2), while Elaeocarpus sylvestris and Michelia chapensis mixed forest had the lowest value (0.20 tC·hm-2). Trunk and root stored more carbon than other organs, and the two organs accounted for 57.5% of the total carbon storage in all tree organs. At the early stage of the five forested ecosystems, the soil layer (0～60 cm) had the largest carbon storage, ranging from 74.52 to119.31 tC-hm-2, and accounted for more than 96.2% of the total carbon storage in the ecosystems. Carbon storage in the plant layer ranged from 0.63 to 2.96 tC-hm-2, which accounted for 0.64 to 3.8% of the total carbon storage of the ecosystems. The litter fall layer had the smallest proportion of the carbon storage within the ecosystems. After conversion of farmland to forestland, the carbon storage was increased 19.48,27.72,41.64,26.82 tC·hm-2 in Cinnamomum camphora pure forests, Cinnamomum camphora and Elaeocarpus sylvestris mixed forests, Michelia chapensis and Manglietia insignis mixed forests, Elaeocarpus sylvestris and Michelia chapensis mixed forests, respectively, but decreased 1.68 tC·hm-2 in Pinus massoniana pure forests. Our results indicated that'Grain for Green' program, especially in the patterns of farmland to mixed forests, had great potential to enhance carbon sequestration in terrestrial ecosystems of southern China.
Cinnamomum camphora pure forests was the most effective in the protection of water resources effectiveness, Elaeocarpus sylvestris and Cinnamomum camphora mixed forests was the worst; Michelia chapensis and Manglietia insignis mixed forests was the most effective for the release of O2 in solid C's effectiveness, Pinus massoniana pure forests was the worst, even showed negative. Michelia chapensis and Manglietia insignis mixed forests was the highest for ecology efficiency, was up to 90794.32 yuan-hm-2·a-1, the second was Elaeocarpus sylvestris and Michelia chapensis mixed forests, up to 71471.14 yuan-hm-2·a-1; the last was Pinus massoniana pure forests, only 9791.88 yuan-hm-2·a-1. It showed that different modle of 'Grain for Green' had different characteristic and advantages, mix forests were better than singleness forest and the mix forests with hardwood and evergreen was the best.
引文
[1]许勤.社区林业发展机制与退耕还林工程案例研究.http://www.docin.com/p-23932506.html
[2]陈云海.纽约州历史上的退耕还林[J].云南林业,2001,(5)：15
[3]许绯绯.1934年——持续长达3天的美国“黑风暴”事件[J].环境导报,2003,(17)：20-21
[4]孙霞,尹林克,孟林,等.退耕还林还草研究之进展[J].干旱区地理,2004,27(2)：221-224
[5]陈大夫.美国的西部开发与“退耕还林,退耕还草,农田休耕”[J]. 林业工作研究,2001,(2)：29-35,28
[6]李世东.中外退耕还林还草之比较及其启示[J].世界林业研究,2000,15(2)：22-27
[7]张蓬涛,杨艳昭,封志明.国外退耕还林实践及其对我国退耕工程实施的启示[J].水土保持通报,2005,25(1)：107-110
[8]李文忠.青海大通退耕还林配置模式与生态功能研究[D].北京林业大学,2005
[9]支玲.从中外退耕还林背景看我国以粮代赈目标的多样性[J].林业经济,2001,(7)：29-31,52
[10]张鸿文.新时期退耕还林工程建设的总体思路[J].林业经济,2002,(3)：18-122
[11]马定渭,邹冬生,戴思慧,等.中国生态问题与退耕还林[J].湖南农业大学学报(社会科学版),2006,26(1)：6-9
[12]贾治邦.谈拓展现代林业三大功能构建三大体系.http://www.chinafpark.net/flfg/more.aspx?id=146
[13]http://www.ahnw.gov.cn/2006nwkx/html/200208/{31021C1D-A7B9-4A36-ABB9-CD8306C84C36}. shtml
[14]曾小舟.退耕还林还草后的林地经营模式探讨[J].农村经济,2002, (6)：5-6
[15]赵新泉,马艳娥.退耕还林的生态作用及实施措施[J].林业资源管理,1999, (3)：36-39
[16]谭海泥,杨杰.论湘西自治州实施退耕还林(草)试点工程[J].中南林业调查规划,2002,21(1)：4-5,22
[17]http://news.sohu.com/s2010/yunguihanzai/
[18]http://www.agri.gov.cn/gndt/t20030919_120634.htm
[19]吴礼军,刘青,李璨,等.全国退耕还林工程进展成效综述[J].林业经济,2009, (9)：21-37
[20]刘璨.林业重点工程对农民收入影响的测度与分析.http://www.econ.shufe.edu.cn/ces/paper/ces_pdf/27/27-2.pdf
[21]彭珂珊.我国西部的生态问题与退耕还林[J].首都师范大学学报,2001,22(1)：100-105
[22]刘璨,武斌,鹿永华.中国退耕还林工程及其所产生的影响[J].林业经济,2009, (10)：41-45
[23]李育材.在全国退耕还林工作会议上的讲话.http://www.forestry.gov.cn/portal/main/s/97/content-4261.html
[24]http://www.ce.cn/xwzx/gnsz/gdxw/200801/22/t20080122_14313112.shtml
[25]王金祥.完善退耕还林政策加快生态环保建设.http://news.sohu.com/20070911/n252089951.shtml
[26]陶接来.湖南退耕还林十年成效分析与对策[J].湖南林业科技,2009,36(5)：49-50
[27]湖南省退耕还林工作领导小组办公室.退耕还林绿播三湘——湖南省退耕还林工程实施十周年调研报告集.2009
[28]发改委副主任就完善退耕还林政策答问.http://www.ce.cn/cysc/ztpd/2007/tghl/toutiao/200709/12/t20070912_12879807.shtml
[29]牛昉.退耕还林还草参与式评估研究[M].西安：西北大学出版社,2007
[30]李颖,唐玉萍.退耕还林(草)工程存在的主要问题探讨[J].毕节师范高等学校学报,2002,20(2)： 77-79
[31]王志宝.国家林业局原局长王志宝在中西部区退还林还草工作座谈会上的讲话(摘要)[J].防护林科技,2001,46(1)：1-3,52
[32]张殿发,张祥华.西北地区退耕还林急需解决的问题及建议[J].中国水土保持,2001,(3)9-11
[33]王汉杰.我国干旱半干旱地区的退耕还林还草与高效生态农牧业建设[J].林业科技开发,2001,15(1)： 7-9
[34]李世荣,李文忠,李福源,等.青海省大同县退耕还林实行区域的人工林生态功能评估的研究[J].水土保持研究,2006,13(3)：252-254
[35]胡华科,郑春燕.3S技术及它在耕地转变成森林时的应用[J].水土保持研究,2006,13(4)：54-56
[36]国家林业局.退耕还林技术与模式[M].北京：中国林业出版社,2001
[37]张尚云.金沙江干热河谷恢复植被与造林技术研究[J].西南林学院学报,1997,17(2)：1-7
[38]李世东.干热干旱河谷区和黄土丘陵沟壑区退耕还林模式初步研究[J].北京林业大学学报,2002,24(3)：35-38
[39]李世东,吴转颖.中西部地区退耕还林还草模式探讨[J].林业科学,2002,38(3)：154-159
[40]Lin Kaiwang, Tiao Xiao. Preliminary result of the grass-tree system for rehabilitation of severely eroded red soils[J]. Advanced in Geoecology,1998,31:1225-1231
[41]Malik R K, Green T H, Brown G F. et al. Use of cover crops in short rotation hardwood plantations to control erosion[J]. Biomass and Bioenergy,2000,18 (16):479-487
[42]Pearce CW, Barbier E, Markendya A. Sustainable Development and Cost Benefit Analysis. London: LEEC Paper 88-03,1988
[43]程喜堂,郝秀斌,张晓霞.退耕地造林模式探索[J].中国林业,2009,39
[44]孙飞达,于洪波,陈文业.安家沟流域农林草复合生态系统类型及模式优化设计[J].草业科学,2009,26(9)：190-194
[45]李世东,刘霞.川渝鄂湘山地丘陵区和长江中下游低山丘陵区退耕还林区域模式研究[J].防护林科技,2004, (6)：3-8
[46]李世东,张丽霞.黄土高原沟壑区退耕还林典型优化模式机理分析[J].应用生态学报,2004,15(9)： 1541-1546
[47]李世东.黄土高原沟壑区退耕还林优化模式研究[J].林业科学,2004,40(5)：71-78
[48]李世东,刘霞.黄土高原区和新疆干旱荒漠区退耕还林区域模式研究[J].防护林科技,2004,(4)： 3-7
[49]李世东,刘霞.东北山地沙地区和京津周围沙地平原区退耕还林区域模式研究[J].防护林科技,2004,(2)：1-6,12
[50]杨正礼.我国西北地区退耕地植被恢复基本途径与模式探讨[J].中国人口.资源与环境,2004,14(5)：37-41
[51]李建安,吕芳德,何志祥,等.湘西坡耕地主要经济林生态经营模式与效果[J].经济林研究,2008,26(4)：12-16
[52]方向京,李贵祥,孟广涛,等.滇东北退耕地生态经济林培育模式及成效分析[J].中国水土保持科学,2009,7(4)：77-81
[53]黄永祥,廖声熙,李昆.金沙江流域鹤庆县退耕还林高效配置模式研究[J].现代农业科技, 2009, (11)：306-307
[54]谷臣文,余亚玲,刘诗健.桑植县退耕还林造林优化模式探讨[J].湖南林业科技,2009,36(3)：94-96
[55]王荣,蔡运龙.西南喀斯特地区退化生态系统整治模式[J].应用生态学报,2010,21(4)：1070-1080
[56]季元祖,赵忠.适宜于泾川县退耕还林(草)植被恢复的优化模式[J].水土保持研究,2009,16(4)：142-145
[57]王连春,翟明普.太行山低山丘陵区植被恢复模式探讨[J].安徽农业科学,2009,37(32)：16083-16084
[58]柴永峰,朱树华.榆阳区生态经济型退耕还林成功造林模式[J].陕西林业科技,2009,(3)：59-62,65
[59]龙廷位.云南省退耕还林工程造林树种及其成效分析[J].林业建设,2008,(4)：18-22
[60]张秋娟.生态经济型灌木树种在退耕还林工程中的发展潜力[J].河南林业科技,2009,29(9)：19-20
[61]马麟英.东兰县森林立地类型的划分及退耕还林树种设计[J].湖北农业科学,2009,48(8)：1862-1865
[62]李剑凌,罗治理,任志刚.干旱风沙区退耕地树种选择和抗旱造林技术[J].防护林科技,2009,(5)：114-116
[63]谌小勇,田大伦,彭元英,等.我国杉木人工林生物产量研究概况[A].见：刘煊章主编.森林生态系统定位研究[C].北京：中国林业出版社,1993
[64]陈国建.退耕还林还草对土地利用变化影响程度研究——以延安生态建设示范区为例[J].自然资源学报,2006,21(2)：274-278
[65]宋乃平,王磊,刘艳华.退耕还林草对黄土丘陵区土地利用的影响[J].资源科学,2006,28(4)： 34-75
[66]满明俊,罗剑朝.陕西省退耕还林工程生态效益评价[J].安徽农业科学,2006,34(18)4735-4737
[67]方向京,李贵祥,张正海.滇东北不同退耕还林类型生物生产量及水土保持效益分析[J].水土保持研究,2009,16(5)：229-232
[68]杜文军,谢双喜,杨洋,等.榆林市榆阳区退耕还林林地侧柏生长情况调查[J].防护林科 技,2009,(4)：11-112,83
[69]高嵩.退耕还林生物量监测及固碳释氧效益初步研究[J].甘肃林业科技,2008,33(3)43-45
[70]董文斌,马玉寿,董全民,等.退耕还草多年生草地地上生物量及牧草营养成分研究[J].草业科学,2010,27(2)：54-58
[71]赵其国.21世纪土壤科学的展望[J].地球科学进展,2001,16(5)：704-709
[72]高国雄,周心澄,史常青,等.北川河流域低位脑山区退耕还林的土壤效应[J].干旱地区农业研究,2008,26(5)：205-212
[73]李世荣,李永贵,段淑怀,等.青海大通退耕还林地土壤理化性状演变研究[J].水土保持研究,2009,16(2)：132-137
[74]蒋丽,陈艳.大通县人工造林对土壤物理性状影响的研究[J].青海农林科技,2009, (3)16-18
[75]童国燕,陈艳,孔繁珍.青海省大通县退耕还林地土壤特性研究[J].青海农林科技,2009,(2)：1-4
[76]韩磊,郑佳丽,贺康宁,等.青海省大通县退耕还林对土壤理化性质的影响[J].水土保持研究,2009,16(3)：100-104
[77]马志林,周心澄,史常青.高寒山区退耕还林不同年限土壤理化性质研究——以青海省大通县为例[J].林业资源管理,2008, (3)：72-76
[78]董文斌,马玉寿,董全民,等.退耕还(林)草多年生栽培草地土壤养分特征研究[J].草业科学,2010,27(4)46-50
[79]张伟华,李文忠,张昊,等.青海大通县退耕还林不同混交配置模式对土壤肥力影响的研究[J].水土保持研究,2005,12(5)：259-262
[80]张伟华,张昊,李文忠,等.青海大通中国沙棘人工林对土壤有机质和含氮量的影响[J].干旱区资源与环境,2005,19(1)：154-158
[81]李文忠,贺永元,张伟华,等.北川河流域退耕还林(草)对土壤质量影响的评价[J].水土保持研究,2005,12(6)：1-3
[82]李文忠,张伟华,张昊,等.青海大通不同退耕还林时间梯度对土壤物理性状的影响[J].干旱区资源与环境,2005,19(3)：137-140
[83]庞奖励,郭美娟,邱海燕,等.关中东部地区退耕还林对土壤微形态的影响研究[J].土壤学 报,2009,46(2)：209-217
[84]于海云,高美兰.黄土高原地区不同退耕还林模式改善土壤物理特性研究[J].内蒙古水利,2009, (3)：9-11
[85]白文娟,焦菊英,马祥华,等.黄土丘陵沟壑区退耕地人工林的土壤环境效应[J].干旱区资源与环境,2005,19(7)：135-141
[86]赵岩,杨越,孙保平,等.黄土丘陵区不同退耕模式对土壤物理性状影响研究——以甘肃定西市为例[J].中国农学通报,2009,25(16)：99-105
[87]王同顺,郭建英,孙保平,等.农牧交错区退耕还林地土壤恢复特征的研究—以内蒙古卓资县为例[J].水土保持研究,2009,16(6)：134-142
[88]杨树,温雨金,刘鸿雁.内蒙古中部地区退耕还林还草后植被与土壤性状的变化[J].水土保持研究,2006,143-149
[89]杨刚,谢永宏,陈心胜,等.退田还湖后洞庭湖区土壤颗粒组成和化学特性的变化[J].生态学报,2009,29(12)：6392-6400
[90]李生,张守攻,姚小华,等.黔中石漠化地区不同土地利用方式对土壤环境的影响[J].长江流域资源与环境,2008,17(3)：384-389
[91]荣 丽,李贤伟,张健,等.华西雨屏区不同退耕模式细根、草根分解及主要土壤微生物功能群动态[J].自然资源学报,2009,24(6)：1069-1079
[92]黄承标,李保平,赖家业,等.桂西北主要退耕还林模式土壤水文—物理性质研究[J].水土保持通报,2009,29(3)：108-112,169
[93]胡建忠,张伟华,李文忠,等.北川河流域退耕地植物群落土壤抗蚀性研究[J].土壤学报,2004,41(6)：854-862
[94]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
[95]高国雄,李文忠,周心澄,等.北川河流域退耕还林不同配置模式的水文效应[J].水土保持学报,2006,20(4)：11-17
[96]郝云庆, 王金锡,李力.北川退耕还林农林复合经营模式的水土保持效应研究[J].水土保持学报,2006,20(4)：17-21
[97]李红,范素芳,张光灿,等.黄土丘陵区退耕还林后不同林地土壤孔隙与贮水特性[J].水土保持通报,2010,30(1)：27-30
[98]陈强,常恩福,毕波,等.滇东南岩溶地区三种退耕还林模式的水土保持效应研究[J].水土保持学报,2006,20(5)：1-33
[99]周刚,田育新,陈国玉,等.湘西北退耕还林初期坡面产流产沙规律研究[J].中国水土保持科学,2009,7(2)：118-122
[100]赵串串,董旭,辛文荣,等.青海湟水河流域不同退耕还林模式水土保持效应[J].水土保持学报,2009,23(5)：26-29
[101]高嵩.不同模式退耕还林地上径流和侵蚀研究[J].甘肃林业科技,2009,34(1)：48-78
[102]傅伯杰,陈利顶,马克明,等.景观生态学原理及应用[M].北京：科学出版社,2001
[103]Lambin E F, Geist H J, Lepers E. Dynamics of land use and land cover change in trop ical regions[J]. Annual Review of Environment and Resources,2003,28:205-241
[104]Riitters K H, O'Neill R V, Hunsaker C T, et al. A factor analysis of landscape pattern and structure metrics[J]. Landscape Ecology,1995,10:23-39
[105]Cain D H, Riitters K, Orvis K. A multiscale analysis of landscape statistics [J]. Landscape Ecology, 1997,12:199-212.
[106]董有福,赵永华,全志杰.退耕政策下小流域景观格局变化研究[J].生态学杂志,2004,23(6)：29-32
[107]赵峰,鞠洪波,黄建文,等.西昌地区实施退耕还林工程后的景观格局变化[J].林业科学,2006,42(1)：56-61
[108]杨朝俊,胡庭兴,刘波,等.关于利用遥感和GIS监测退耕还林区域森林动态变化的研究[J].遥感技术与应用,2006,(1)：38-40
[109]张博,孙保平,郭建英,等.甘肃省定西市安定区退耕还林前后土地利用/覆盖动态变化研究[J].中国农学通报,2009,25(18)：161-165
[110]张志明,孙长青,欧晓昆.退耕还林政策对山地植被空间格局变化的驱动分析[J].山地学报,2009,27(5)：513-523
[111]朱战强,刘黎明,张军连.退耕还林对宁南黄土丘陵区景观格局的影响——以中庄村典型小流域为例[J].生态学报,2010,30(1)：146-154
[112]Robert T, Watson I R, Noble B B. Land Use Land-Use Change and Forestry Special Report of the Intergovernmental Panel on Climate Change. Cambridge:Cambridge University Press,2000
[113]Vesterdal L, Ritter E, Gundersen P. Change in soil organic carbon following afforestation of former arable land. Forest Ecology and Management,2002.169:137-147
[114]Nabuurs G J, Dolman A J, Verkaik E, et al. Consequences for industrialised countries'commitment, the monitoring needs, and possible side effects [J]. Environ. Sci. Policy,2000,3:123-134
[115]陈健生.退耕还林与西部可持续发展[M].昆明：西南财政大学出版社,2006
[116]Laclau P. Biomass and carbon sequestration of ponderosapine plantations and native cypress forests in northwest Patagonia[J]. For. Ecol. Man.,2003,180:317-333
[117]Richter D D, Markewitz D, Trumbore S E, et al. Rapid accumulation and turnover of soil carbon in a reestablishing forest[J]. Nature,1999,400:56-58
[118]Hooker T D, Comp ton J E. Forest ecosystem carbon and nitrogen accumulation during the first century after agricultural abandonment J]. Ecological Applications,2003,13:299-313
[119]Huntington T G. Carbon sequestration in an aggrading forest ecosystem in the Southeastern USA[J]. Soil Science Society of Am erica Journal,1995,59:1459-1467
[120]Guo L B, Gifforod R M. Soil carbon stocks and land use change:a meta analysis[J]. Global Change Biology,2002, (8):345-360
[121]Post W M, Kwon K C. Soil carbon sequestration and land-use change:Processes and potential[J]. Global Change Biol,2000,6:317-327
[122]Johnson P N, Misra S K, Ervin R T. A qualitative choice analysis of factors influencing post-CRP land use decisions[J]. Journal of Agricultural and Applied Economics,1997,29 (1):163-173
[123]聂道平,徐德应,王兵.全球碳循环与森林关系的研究—问题与进展[J].世界林业研究,1997,(5)：33-40
[124]Paul K I, Polglase P J, Nyakuengama J G, et al. Change in soil carbon following afforestation[J]. Forest Ecology and Management,2002,168:241-257
[125]Richter D D, Markewitz D, Trumbore S E, et al. Rapid accumulation and turnover of soil carbon in a re-establishing forest[J]. Nature,1999,400:56-58
[126]Mendham DS,Connell AM,Grove TS. Change in soil carbon after land clearing or afforestation in highlyweathered lateritic and sandy soils of south-western Australia Agric[J]. Ecosystem Environment,2003,95:143-156
[127]李世东,翟洪波.世界林业生态工程对比研究[J].生态学报,2002,22(11)：1977-1982
[128]白雪爽,胡亚林,曾德慧,等.半干旱沙区退耕还林对碳储量和分配格局的影响[J].生态学 杂志,2008,27(10)：1647-1652
[129]吴小山,黄从德.退耕还林地桦木林生态系统碳素密度、贮量与空间分布[J].生态学杂志2007,26(3)：323-326
[130]黄从德,张健,邓玉林,等.退耕还林地在植被恢复初期碳储量及分配格局研究[J].水土保持学报,2007,21(4)：130-133
[131]胡亚林,曾德慧,姜涛.科尔沁沙地退耕杨树人工林生态系统C、N、P储量和分配格局[J].生态学报,2009,29(8)：4206-4214
[132]彭文英,张科利,陈瑶,等.黄土坡耕地退耕还林后土壤理化性质变化研究[J].自然资源学报,2005,20(2)：272-278
[133]彭文英,张科利,杨勤科.退耕还林对黄土高原地区土壤有机碳影响预测[J].地域研究与开发,2006,25(3)：94-99
[134]龙键,邓启琼,江新荣,等.西南喀斯特地区退耕还林(草)模式对土壤肥力质量演变的影响.应用生态学报,2005,16(7)：1279-1284
[135]王春梅,刘艳红,邵彬,等.量化退耕还林后土壤碳变化[J].北京林业大学学报,2007,29(3)：112-119
[136]陈亮中,肖文发,唐万鹏,等.三峡库区几种退耕还林模式下土壤有机碳研究[J].林业科学,2007,43(4)：111-114
[137]Houghto J T, Ding Y, Griggs D J. Climate Change 2001:The Scientific Basis Cont ribution of Working Group Ⅰ to the Third Assessment Report of the Intergovernmental Panel on Climate Change (IPCC) [M]. Cambridge:Cambridge University Press,2001:180-245.
[138]蔡丽莎,陈先刚,郭颖,等.贵州省退耕还林工程碳汇潜力预测[J].浙江林学院学报,2009,26(5)：722-728
[139]蔡丽莎,陈先刚.贵州省退耕还林工程主要树种碳汇潜力预测[J].山东林业科技,2009,181(2)： 15-18
[140]陈先刚,赵晓惠,陆梅,等.四川省退耕还林工程林碳汇潜力研究[J].浙江林业科技,2009,29(5)：19-28
[141]陈先刚,张一平,詹卉.云南退耕还林工程林木生物质碳汇潜力[J].林业科学,2008,44(5)：24-30
[142]陈先刚,张一平,潘昌平.重庆市退耕还林工程林固碳潜力估算[J].中南林业科技大学学报, 2009,29(4)：7-15
[143]国务院发展研究中心.西部大开发指南——统计信息专辑[M].北京：中国社会科学出版社,2000,19-24
[144]国家退耕还林办分室.退耕还林指导与实践[M].北京：中国农业科学技术出版社,2003
[145]杨正礼.我国退耕还林研究进展与基本途径探讨[J].林业科学研究,2004,17(4)：512-518
[146]史良树.SPOT-5数据在退耕还林测中的应用研究——以山西省古交市嘉乐泉乡为例[D].北京：中国林业科学研究院,2004
[147]王晓光,王珠娜,余雪标,等.退耕还林生态效益评价指标体系研究[J].防护林科技,2006(11)：51-53.
[148]姚清亮,陆贵巧,杜剑,等.关于承德市退耕还林工程生态效益评价研究[J].河北农业大学学报,2009,32(6)：57-61
[149]周文渊,赵岩,郭建英,等.安定区退耕还林工程的生态效益评价[J].中国农学通报,2009,25(20)：115-120
[150]杨建波,王利.退耕还林生态效益评价方法[J].中国土地科学,2003,11(5)：54-58
[151]田大伦.杉木林生态系统定位研究方法[M].北京：科学出版社,2004
[152]张学权,胡庭兴,李伟,等.华西雨屏退耕地不同植被经营模式坡面径流和产沙特征分析[J].水土保持学报,2004,18(6)：27-33
[153]温仲明,焦峰,刘宝元,等.黄土高原森林草原区退耕地植物自然恢复与土壤养分变化[J].应用生态学,2005,16(11)：2025-2029
[154]张国斌,田大伦,方晰,等.湖南会同退耕还林不同造林模式下土壤有机碳分布特征[J].中南林业科技大学学报,2008,28(2)：8-12
[155]潘维俦,田大伦.森林生态系统第一性生产量的测定技术与方法[J].湖南林业科学,1981,(2)：1-12
[156]杨树,温雨金,刘鸿雁.内蒙古中部地区退耕还林还草后植被与土壤性状的变化[J].水土保持研究,2006,13(4)：143-145,149
[157]黄宇,汪思龙,冯宗炜,等.不同人工林生态系统林地土壤质量评价[J].应用生态学报,2004,15 (12)：2199-2205
[158]Acosta Mratine Martinez V, Reicher Z, Bischoff M, et al. The role of tree leaf mulch and nitrogen fertilizer on turf grass soilquality[J].Biolfertsoils,1999,29:55-61
[159]Whalley W R, Dumitru E, Dexter A R. Biological effects of soil compaction[J]. Soil Tillers,1995, 35:53-68
[160]Zheng Y S, Ding Y X. Effect of mixed forests of Chinese-fir and Tsoong's tree on soil properties[J].Pedosphere,1998,8 (2):161-168
[161]杨玉盛,俞新妥,邱仁辉.栽杉留阔模式生产力和土壤肥力的研究[J].林业科学,1999,35(4)： 9-13
[162]高雪松,邓良基,张世熔.不同利用方式与坡位土壤物理性质及养分特征分析[J].水土保持学报,2005,19(2)：53-60,79
[163]王涌清,孙昭荣,刘秀奇.潮土及盐化潮土中的微团聚体及有机质在各组微团聚体中的分布[J].土壤肥料,1983,19(4)：10-13
[164]唐炎林,邓晓保,李玉武,等.西双版纳不同林分土壤机械组成及其肥力比较[J].中南林业科技大学学报(自然科学版),2007,27(1)：70-76
[165]杨万勤,张健,胡庭兴,等.森林土壤生态学[M].成都：四川科学技术出版社,2006：335-341
[166]北京林学院主编.土壤学[M].北京：中国林业出版社,1982,98-117
[167]湖南省农业厅编著.湖南土壤[M].北京：农业出版社,1989
[168]徐成龙,林昌虎,何腾兵,等.黔中石漠化地区生态恢复过程中土壤养分变异特征[J].水土保持通报,2004,24(6)：22-29,89
[169]陈书玉.环境影响评价[M].北京：高等教育出版社,2002,160-162
[170]王云,魏复盛.土壤环境化学[M].北京：中国环境科学出版社,1995
[171]朱建军,崔保山,杨志峰,等.纵向岭谷区公路沿线土壤表层重金属空间分异特征[J].生态学报,2006,26(1)：146-153
[172]Adejuwon J O, Ekanade O. A comparison of soil properties under different land use types in a part of the Nigerian Cocoa Belt[J]. Catena,1988,15:319-331
[173]Lowery B, Swan J, Schumacher T, et al. Physical properties of selected soils by erosion class[J]. Soil Water Conserv.1995,50:306-311
[174]潘维俦,田大伦,文仕知,等.集水区内森林生态系统的养分分析[J].中南林学院学报,1988,8(2)：115-122
[175][美]F.B索尔兹伯里,C.罗斯.植物生理学[M].北京：科学出版社,1981
[176]黄健辉,陈灵灵.北京百花山附近杂灌丛的化学元素含量特征[J].植物生态学与地植物学学 报,1991,15(3)：224-232.
[177]刘茜,刘煊章,张昌剑.天然次生白栎林生物量与营养元素含量的研究[J].林业科学,1997,33(Sp2)：157-166
[178]蒋有绪.川西亚高山冷杉林枯枝落叶层的群落学作用[J].植物生态学与地植物丛刊,1981,6(2)：89-98
[179]张万儒,许本彤.山地森林土壤枯枝落叶层结构和功能研究[J].土壤学报,1990,27(2)：121-131
[180]陈堆全.木荷凋落物分解及对土壤作用规律的研究[J].福建林业科技,2001,28(2)：86-89
[181]余清发,温达志,张德强.鼎湖山南亚热带常绿阔叶林定位研究(Ⅷ)锥栗、黄果厚壳桂群落营养元素生物循环[A].见：中国科学院鼎湖山森林生态系统定位研究站、鼎湖山国家级级保护区管理处编.热带亚热带森林生态系统研究(第8集)[C].北京：气象出版社,1998
[182]蚁伟民,丁明懋,张祝平,等.鼎湖山黄果厚壳桂群落的凋落物及其氮素动态[J].植物生态学报,1994,18(3)：228-235
[183]潘瑞炽,董愚得编.植物生理学(第三版).北京：高等教育出版社,1995,32-40
[184]许振英.十多年来我国畜牧学科中微量元素研究.中国动物营养学报,1989,1(1)：1-9
[185]缪自基主编.微量元素的环境化学与生物影响[M].北京：中国环境科学出版社,1992
[186]刑廷铣,李丽立,彭艺.土壤—作物—动物生态体系中微量元素含量[J].生态学杂志,2000,19(2)：24-29
[187]Chapin F S. The Mineral Nutrition of wild plants[J]. Annu. Rev. Ecol. Syst,1980,11:233-260
[188]计维农.太湖流域主要粮食作物中19种元素背景值及其特征[J].环境科学学报,1987,7(1)：86-92
[189]杜荣.我国饲料中微量矿物质浅析[J].中国畜牧杂志,1989,25(4)：20-23
[190]佘崇祥.湖南红壤中微量元素的含量与分布[J].农业现代化研究,1994,增(1)：41-45
[191]许嘉琳,鲍子平,杨居荣,等.农作物中铅、镉、铜的化学形态[J].应用生态学报,1991,2(3)：244-248
[192]赵敏,周广胜.中国森林生态系统的植物碳贮量及其影响因子分析[J].地理科学,2004,24(1)：50-54
[193]Fang J, Chen A, Peng C, et al. Changes in forest biomass carbon storage in China between 1949 and 1998[J]. Science,2001,292:2320-2322.
[194]Zhang X O, Xu D Y. Potential carbon sequestration in China's forests[J]. Enviromental Science & Policy,2003,6:421-432.
[195]陈广生,田汉勤.土地利用／覆盖变化对陆地生态系统碳循环的影响[J].植物生态学报,2007,31(2)：189-204
[196]Andrews S S, Karlen D L, Cambardella C A. The soil management assessment framework:a quantitative soil quality evaluation method[J]. Soil Science Society of American Journal,2004,68: 1945-1962.
[197]张华,张甘霖,漆智平,等.热带地区农场尺度土壤质量现状的系统评价[J].土壤学报,2003,40(2)：186-193
[198]Jobbagy E G, Jackson R B. The vertical distribution of soil organic carbon and it's relation to climate and vegetation[J]. Ecological Application,2002,10(2):423-436.
[199]阮宏华,姜志林,高苏铭.苏南丘陵主要森林类型碳循环研究—含量与分布规律[J].生态学杂志,1997,16(6)：17-21
[200]方晰,田大伦,项文化.速生阶段杉木人工林碳素密度、贮量和分布[J].林业科学,2002,38(3)： 14-19
[201]马钦彦,陈遐林,王娟,等.华北主要森林类型建群种的含碳率分析[J].北京林业大学学报,2002,24(5/6)：96-100
[202]Zinn Y L, Resck D V S, da Silva J E. Soil organic carbon as affected by afforestation with Eucalyptus and Pinus in the Cerrado region of Brazil[J]. Forest Ecology and Management,2002,166: 285-294.
[203]Turner J, Lambert M. Change in organic carbon in forest plantation soils in eastern Australis[J]. Forest Ecology and Management,2000,133:231-247.
[204]吴建国,张小全,徐德应.土地利用变化对土壤有机碳贮量的影响[J].应用生态学报,2004,15(4)： 593-599
[205]田大伦著.马尾松和湿地松林生态系统结构与功能[M].北京：科学出版社,2005
[206]章继刚.创意农业：促进农民增收致富的新途径[J].改革与开放,2008, (7)：9-10
[207]袁红军,曹国璠,晏世强.退耕还林生态效益评价研究与展望[J].现代农业科技,2009,(2)：239-242
[208]李丕蓉,彭培好,朱琴,等.四川盆地周边地区退耕还林工程经济效益分析[J].国土资源科 技管理,2008,25(1)：20-23
[209]康文星,田大伦.杉木人工林采代表后水源涵养和固土保肥效益损失的评价[J].林业科学,2002,38(1)：111-115
[210]周冰冰,李忠魁.北京市森林资源价值[M].北京：中国林业出版社,2000
[211]http://www.cnenv.com/NewsShow.aspx?id=296
[212]薛达元,包浩生,李文华.长白山自然保护区森林生态系统间接经济价值评估[J].中国环境科学,1999,19(3)：247-252
[213]侯元兆,张佩昌,王琦.中国森林资源核算研究[M].北京：中国林业出版社,1995,134-136
[214]靳芳,鲁绍伟,余新晓,等.中国森林生态系统服务功能及其价值评价[J].应用生态学报,2005,16(8)：1531-1536
[215]余新晓,秦永肚,陈丽华,等.北京山地森林生态系统服务功能及其价值初步研究[J].生态学报,2002,22(5)：783-786
[216]薛达元.生物多样性经济价值评估——长白山自然保护区案例研究[M].北京：中国环境科学出版社,1997
[2]陈云海.纽约州历史上的退耕还林[J].云南林业,2001,(5)：15
[3]许绯绯.1934年——持续长达3天的美国“黑风暴”事件[J].环境导报,2003,(17)：20-21
[4]孙霞,尹林克,孟林,等.退耕还林还草研究之进展[J].干旱区地理,2004,27(2)：221-224
[5]陈大夫.美国的西部开发与“退耕还林,退耕还草,农田休耕”[J]. 林业工作研究,2001,(2)：29-35,28
[6]李世东.中外退耕还林还草之比较及其启示[J].世界林业研究,2000,15(2)：22-27
[7]张蓬涛,杨艳昭,封志明.国外退耕还林实践及其对我国退耕工程实施的启示[J].水土保持通报,2005,25(1)：107-110
[8]李文忠.青海大通退耕还林配置模式与生态功能研究[D].北京林业大学,2005
[9]支玲.从中外退耕还林背景看我国以粮代赈目标的多样性[J].林业经济,2001,(7)：29-31,52
[10]张鸿文.新时期退耕还林工程建设的总体思路[J].林业经济,2002,(3)：18-122
[11]马定渭,邹冬生,戴思慧,等.中国生态问题与退耕还林[J].湖南农业大学学报(社会科学版),2006,26(1)：6-9
[12]贾治邦.谈拓展现代林业三大功能构建三大体系.http://www.chinafpark.net/flfg/more.aspx?id=146
[13]http://www.ahnw.gov.cn/2006nwkx/html/200208/{31021C1D-A7B9-4A36-ABB9-CD8306C84C36}. shtml
[14]曾小舟.退耕还林还草后的林地经营模式探讨[J].农村经济,2002, (6)：5-6
[15]赵新泉,马艳娥.退耕还林的生态作用及实施措施[J].林业资源管理,1999, (3)：36-39
[16]谭海泥,杨杰.论湘西自治州实施退耕还林(草)试点工程[J].中南林业调查规划,2002,21(1)：4-5,22
[17]http://news.sohu.com/s2010/yunguihanzai/
[18]http://www.agri.gov.cn/gndt/t20030919_120634.htm
[19]吴礼军,刘青,李璨,等.全国退耕还林工程进展成效综述[J].林业经济,2009, (9)：21-37
[20]刘璨.林业重点工程对农民收入影响的测度与分析.http://www.econ.shufe.edu.cn/ces/paper/ces_pdf/27/27-2.pdf
[21]彭珂珊.我国西部的生态问题与退耕还林[J].首都师范大学学报,2001,22(1)：100-105
[22]刘璨,武斌,鹿永华.中国退耕还林工程及其所产生的影响[J].林业经济,2009, (10)：41-45
[23]李育材.在全国退耕还林工作会议上的讲话.http://www.forestry.gov.cn/portal/main/s/97/content-4261.html
[24]http://www.ce.cn/xwzx/gnsz/gdxw/200801/22/t20080122_14313112.shtml
[25]王金祥.完善退耕还林政策加快生态环保建设.http://news.sohu.com/20070911/n252089951.shtml
[26]陶接来.湖南退耕还林十年成效分析与对策[J].湖南林业科技,2009,36(5)：49-50
[27]湖南省退耕还林工作领导小组办公室.退耕还林绿播三湘——湖南省退耕还林工程实施十周年调研报告集.2009
[28]发改委副主任就完善退耕还林政策答问.http://www.ce.cn/cysc/ztpd/2007/tghl/toutiao/200709/12/t20070912_12879807.shtml
[29]牛昉.退耕还林还草参与式评估研究[M].西安：西北大学出版社,2007
[30]李颖,唐玉萍.退耕还林(草)工程存在的主要问题探讨[J].毕节师范高等学校学报,2002,20(2)： 77-79
[31]王志宝.国家林业局原局长王志宝在中西部区退还林还草工作座谈会上的讲话(摘要)[J].防护林科技,2001,46(1)：1-3,52
[32]张殿发,张祥华.西北地区退耕还林急需解决的问题及建议[J].中国水土保持,2001,(3)9-11
[33]王汉杰.我国干旱半干旱地区的退耕还林还草与高效生态农牧业建设[J].林业科技开发,2001,15(1)： 7-9
[34]李世荣,李文忠,李福源,等.青海省大同县退耕还林实行区域的人工林生态功能评估的研究[J].水土保持研究,2006,13(3)：252-254
[35]胡华科,郑春燕.3S技术及它在耕地转变成森林时的应用[J].水土保持研究,2006,13(4)：54-56
[36]国家林业局.退耕还林技术与模式[M].北京：中国林业出版社,2001
[37]张尚云.金沙江干热河谷恢复植被与造林技术研究[J].西南林学院学报,1997,17(2)：1-7
[38]李世东.干热干旱河谷区和黄土丘陵沟壑区退耕还林模式初步研究[J].北京林业大学学报,2002,24(3)：35-38
[39]李世东,吴转颖.中西部地区退耕还林还草模式探讨[J].林业科学,2002,38(3)：154-159
[40]Lin Kaiwang, Tiao Xiao. Preliminary result of the grass-tree system for rehabilitation of severely eroded red soils[J]. Advanced in Geoecology,1998,31:1225-1231
[41]Malik R K, Green T H, Brown G F. et al. Use of cover crops in short rotation hardwood plantations to control erosion[J]. Biomass and Bioenergy,2000,18 (16):479-487
[42]Pearce CW, Barbier E, Markendya A. Sustainable Development and Cost Benefit Analysis. London: LEEC Paper 88-03,1988
[43]程喜堂,郝秀斌,张晓霞.退耕地造林模式探索[J].中国林业,2009,39
[44]孙飞达,于洪波,陈文业.安家沟流域农林草复合生态系统类型及模式优化设计[J].草业科学,2009,26(9)：190-194
[45]李世东,刘霞.川渝鄂湘山地丘陵区和长江中下游低山丘陵区退耕还林区域模式研究[J].防护林科技,2004, (6)：3-8
[46]李世东,张丽霞.黄土高原沟壑区退耕还林典型优化模式机理分析[J].应用生态学报,2004,15(9)： 1541-1546
[47]李世东.黄土高原沟壑区退耕还林优化模式研究[J].林业科学,2004,40(5)：71-78
[48]李世东,刘霞.黄土高原区和新疆干旱荒漠区退耕还林区域模式研究[J].防护林科技,2004,(4)： 3-7
[49]李世东,刘霞.东北山地沙地区和京津周围沙地平原区退耕还林区域模式研究[J].防护林科技,2004,(2)：1-6,12
[50]杨正礼.我国西北地区退耕地植被恢复基本途径与模式探讨[J].中国人口.资源与环境,2004,14(5)：37-41
[51]李建安,吕芳德,何志祥,等.湘西坡耕地主要经济林生态经营模式与效果[J].经济林研究,2008,26(4)：12-16
[52]方向京,李贵祥,孟广涛,等.滇东北退耕地生态经济林培育模式及成效分析[J].中国水土保持科学,2009,7(4)：77-81
[53]黄永祥,廖声熙,李昆.金沙江流域鹤庆县退耕还林高效配置模式研究[J].现代农业科技, 2009, (11)：306-307
[54]谷臣文,余亚玲,刘诗健.桑植县退耕还林造林优化模式探讨[J].湖南林业科技,2009,36(3)：94-96
[55]王荣,蔡运龙.西南喀斯特地区退化生态系统整治模式[J].应用生态学报,2010,21(4)：1070-1080
[56]季元祖,赵忠.适宜于泾川县退耕还林(草)植被恢复的优化模式[J].水土保持研究,2009,16(4)：142-145
[57]王连春,翟明普.太行山低山丘陵区植被恢复模式探讨[J].安徽农业科学,2009,37(32)：16083-16084
[58]柴永峰,朱树华.榆阳区生态经济型退耕还林成功造林模式[J].陕西林业科技,2009,(3)：59-62,65
[59]龙廷位.云南省退耕还林工程造林树种及其成效分析[J].林业建设,2008,(4)：18-22
[60]张秋娟.生态经济型灌木树种在退耕还林工程中的发展潜力[J].河南林业科技,2009,29(9)：19-20
[61]马麟英.东兰县森林立地类型的划分及退耕还林树种设计[J].湖北农业科学,2009,48(8)：1862-1865
[62]李剑凌,罗治理,任志刚.干旱风沙区退耕地树种选择和抗旱造林技术[J].防护林科技,2009,(5)：114-116
[63]谌小勇,田大伦,彭元英,等.我国杉木人工林生物产量研究概况[A].见：刘煊章主编.森林生态系统定位研究[C].北京：中国林业出版社,1993
[64]陈国建.退耕还林还草对土地利用变化影响程度研究——以延安生态建设示范区为例[J].自然资源学报,2006,21(2)：274-278
[65]宋乃平,王磊,刘艳华.退耕还林草对黄土丘陵区土地利用的影响[J].资源科学,2006,28(4)： 34-75
[66]满明俊,罗剑朝.陕西省退耕还林工程生态效益评价[J].安徽农业科学,2006,34(18)4735-4737
[67]方向京,李贵祥,张正海.滇东北不同退耕还林类型生物生产量及水土保持效益分析[J].水土保持研究,2009,16(5)：229-232
[68]杜文军,谢双喜,杨洋,等.榆林市榆阳区退耕还林林地侧柏生长情况调查[J].防护林科 技,2009,(4)：11-112,83
[69]高嵩.退耕还林生物量监测及固碳释氧效益初步研究[J].甘肃林业科技,2008,33(3)43-45
[70]董文斌,马玉寿,董全民,等.退耕还草多年生草地地上生物量及牧草营养成分研究[J].草业科学,2010,27(2)：54-58
[71]赵其国.21世纪土壤科学的展望[J].地球科学进展,2001,16(5)：704-709
[72]高国雄,周心澄,史常青,等.北川河流域低位脑山区退耕还林的土壤效应[J].干旱地区农业研究,2008,26(5)：205-212
[73]李世荣,李永贵,段淑怀,等.青海大通退耕还林地土壤理化性状演变研究[J].水土保持研究,2009,16(2)：132-137
[74]蒋丽,陈艳.大通县人工造林对土壤物理性状影响的研究[J].青海农林科技,2009, (3)16-18
[75]童国燕,陈艳,孔繁珍.青海省大通县退耕还林地土壤特性研究[J].青海农林科技,2009,(2)：1-4
[76]韩磊,郑佳丽,贺康宁,等.青海省大通县退耕还林对土壤理化性质的影响[J].水土保持研究,2009,16(3)：100-104
[77]马志林,周心澄,史常青.高寒山区退耕还林不同年限土壤理化性质研究——以青海省大通县为例[J].林业资源管理,2008, (3)：72-76
[78]董文斌,马玉寿,董全民,等.退耕还(林)草多年生栽培草地土壤养分特征研究[J].草业科学,2010,27(4)46-50
[79]张伟华,李文忠,张昊,等.青海大通县退耕还林不同混交配置模式对土壤肥力影响的研究[J].水土保持研究,2005,12(5)：259-262
[80]张伟华,张昊,李文忠,等.青海大通中国沙棘人工林对土壤有机质和含氮量的影响[J].干旱区资源与环境,2005,19(1)：154-158
[81]李文忠,贺永元,张伟华,等.北川河流域退耕还林(草)对土壤质量影响的评价[J].水土保持研究,2005,12(6)：1-3
[82]李文忠,张伟华,张昊,等.青海大通不同退耕还林时间梯度对土壤物理性状的影响[J].干旱区资源与环境,2005,19(3)：137-140
[83]庞奖励,郭美娟,邱海燕,等.关中东部地区退耕还林对土壤微形态的影响研究[J].土壤学 报,2009,46(2)：209-217
[84]于海云,高美兰.黄土高原地区不同退耕还林模式改善土壤物理特性研究[J].内蒙古水利,2009, (3)：9-11
[85]白文娟,焦菊英,马祥华,等.黄土丘陵沟壑区退耕地人工林的土壤环境效应[J].干旱区资源与环境,2005,19(7)：135-141
[86]赵岩,杨越,孙保平,等.黄土丘陵区不同退耕模式对土壤物理性状影响研究——以甘肃定西市为例[J].中国农学通报,2009,25(16)：99-105
[87]王同顺,郭建英,孙保平,等.农牧交错区退耕还林地土壤恢复特征的研究—以内蒙古卓资县为例[J].水土保持研究,2009,16(6)：134-142
[88]杨树,温雨金,刘鸿雁.内蒙古中部地区退耕还林还草后植被与土壤性状的变化[J].水土保持研究,2006,143-149
[89]杨刚,谢永宏,陈心胜,等.退田还湖后洞庭湖区土壤颗粒组成和化学特性的变化[J].生态学报,2009,29(12)：6392-6400
[90]李生,张守攻,姚小华,等.黔中石漠化地区不同土地利用方式对土壤环境的影响[J].长江流域资源与环境,2008,17(3)：384-389
[91]荣 丽,李贤伟,张健,等.华西雨屏区不同退耕模式细根、草根分解及主要土壤微生物功能群动态[J].自然资源学报,2009,24(6)：1069-1079
[92]黄承标,李保平,赖家业,等.桂西北主要退耕还林模式土壤水文—物理性质研究[J].水土保持通报,2009,29(3)：108-112,169
[93]胡建忠,张伟华,李文忠,等.北川河流域退耕地植物群落土壤抗蚀性研究[J].土壤学报,2004,41(6)：854-862
[94]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
[95]高国雄,李文忠,周心澄,等.北川河流域退耕还林不同配置模式的水文效应[J].水土保持学报,2006,20(4)：11-17
[96]郝云庆, 王金锡,李力.北川退耕还林农林复合经营模式的水土保持效应研究[J].水土保持学报,2006,20(4)：17-21
[97]李红,范素芳,张光灿,等.黄土丘陵区退耕还林后不同林地土壤孔隙与贮水特性[J].水土保持通报,2010,30(1)：27-30
[98]陈强,常恩福,毕波,等.滇东南岩溶地区三种退耕还林模式的水土保持效应研究[J].水土保持学报,2006,20(5)：1-33
[99]周刚,田育新,陈国玉,等.湘西北退耕还林初期坡面产流产沙规律研究[J].中国水土保持科学,2009,7(2)：118-122
[100]赵串串,董旭,辛文荣,等.青海湟水河流域不同退耕还林模式水土保持效应[J].水土保持学报,2009,23(5)：26-29
[101]高嵩.不同模式退耕还林地上径流和侵蚀研究[J].甘肃林业科技,2009,34(1)：48-78
[102]傅伯杰,陈利顶,马克明,等.景观生态学原理及应用[M].北京：科学出版社,2001
[103]Lambin E F, Geist H J, Lepers E. Dynamics of land use and land cover change in trop ical regions[J]. Annual Review of Environment and Resources,2003,28:205-241
[104]Riitters K H, O'Neill R V, Hunsaker C T, et al. A factor analysis of landscape pattern and structure metrics[J]. Landscape Ecology,1995,10:23-39
[105]Cain D H, Riitters K, Orvis K. A multiscale analysis of landscape statistics [J]. Landscape Ecology, 1997,12:199-212.
[106]董有福,赵永华,全志杰.退耕政策下小流域景观格局变化研究[J].生态学杂志,2004,23(6)：29-32
[107]赵峰,鞠洪波,黄建文,等.西昌地区实施退耕还林工程后的景观格局变化[J].林业科学,2006,42(1)：56-61
[108]杨朝俊,胡庭兴,刘波,等.关于利用遥感和GIS监测退耕还林区域森林动态变化的研究[J].遥感技术与应用,2006,(1)：38-40
[109]张博,孙保平,郭建英,等.甘肃省定西市安定区退耕还林前后土地利用/覆盖动态变化研究[J].中国农学通报,2009,25(18)：161-165
[110]张志明,孙长青,欧晓昆.退耕还林政策对山地植被空间格局变化的驱动分析[J].山地学报,2009,27(5)：513-523
[111]朱战强,刘黎明,张军连.退耕还林对宁南黄土丘陵区景观格局的影响——以中庄村典型小流域为例[J].生态学报,2010,30(1)：146-154
[112]Robert T, Watson I R, Noble B B. Land Use Land-Use Change and Forestry Special Report of the Intergovernmental Panel on Climate Change. Cambridge:Cambridge University Press,2000
[113]Vesterdal L, Ritter E, Gundersen P. Change in soil organic carbon following afforestation of former arable land. Forest Ecology and Management,2002.169:137-147
[114]Nabuurs G J, Dolman A J, Verkaik E, et al. Consequences for industrialised countries'commitment, the monitoring needs, and possible side effects [J]. Environ. Sci. Policy,2000,3:123-134
[115]陈健生.退耕还林与西部可持续发展[M].昆明：西南财政大学出版社,2006
[116]Laclau P. Biomass and carbon sequestration of ponderosapine plantations and native cypress forests in northwest Patagonia[J]. For. Ecol. Man.,2003,180:317-333
[117]Richter D D, Markewitz D, Trumbore S E, et al. Rapid accumulation and turnover of soil carbon in a reestablishing forest[J]. Nature,1999,400:56-58
[118]Hooker T D, Comp ton J E. Forest ecosystem carbon and nitrogen accumulation during the first century after agricultural abandonment J]. Ecological Applications,2003,13:299-313
[119]Huntington T G. Carbon sequestration in an aggrading forest ecosystem in the Southeastern USA[J]. Soil Science Society of Am erica Journal,1995,59:1459-1467
[120]Guo L B, Gifforod R M. Soil carbon stocks and land use change:a meta analysis[J]. Global Change Biology,2002, (8):345-360
[121]Post W M, Kwon K C. Soil carbon sequestration and land-use change:Processes and potential[J]. Global Change Biol,2000,6:317-327
[122]Johnson P N, Misra S K, Ervin R T. A qualitative choice analysis of factors influencing post-CRP land use decisions[J]. Journal of Agricultural and Applied Economics,1997,29 (1):163-173
[123]聂道平,徐德应,王兵.全球碳循环与森林关系的研究—问题与进展[J].世界林业研究,1997,(5)：33-40
[124]Paul K I, Polglase P J, Nyakuengama J G, et al. Change in soil carbon following afforestation[J]. Forest Ecology and Management,2002,168:241-257
[125]Richter D D, Markewitz D, Trumbore S E, et al. Rapid accumulation and turnover of soil carbon in a re-establishing forest[J]. Nature,1999,400:56-58
[126]Mendham DS,Connell AM,Grove TS. Change in soil carbon after land clearing or afforestation in highlyweathered lateritic and sandy soils of south-western Australia Agric[J]. Ecosystem Environment,2003,95:143-156
[127]李世东,翟洪波.世界林业生态工程对比研究[J].生态学报,2002,22(11)：1977-1982
[128]白雪爽,胡亚林,曾德慧,等.半干旱沙区退耕还林对碳储量和分配格局的影响[J].生态学 杂志,2008,27(10)：1647-1652
[129]吴小山,黄从德.退耕还林地桦木林生态系统碳素密度、贮量与空间分布[J].生态学杂志2007,26(3)：323-326
[130]黄从德,张健,邓玉林,等.退耕还林地在植被恢复初期碳储量及分配格局研究[J].水土保持学报,2007,21(4)：130-133
[131]胡亚林,曾德慧,姜涛.科尔沁沙地退耕杨树人工林生态系统C、N、P储量和分配格局[J].生态学报,2009,29(8)：4206-4214
[132]彭文英,张科利,陈瑶,等.黄土坡耕地退耕还林后土壤理化性质变化研究[J].自然资源学报,2005,20(2)：272-278
[133]彭文英,张科利,杨勤科.退耕还林对黄土高原地区土壤有机碳影响预测[J].地域研究与开发,2006,25(3)：94-99
[134]龙键,邓启琼,江新荣,等.西南喀斯特地区退耕还林(草)模式对土壤肥力质量演变的影响.应用生态学报,2005,16(7)：1279-1284
[135]王春梅,刘艳红,邵彬,等.量化退耕还林后土壤碳变化[J].北京林业大学学报,2007,29(3)：112-119
[136]陈亮中,肖文发,唐万鹏,等.三峡库区几种退耕还林模式下土壤有机碳研究[J].林业科学,2007,43(4)：111-114
[137]Houghto J T, Ding Y, Griggs D J. Climate Change 2001:The Scientific Basis Cont ribution of Working Group Ⅰ to the Third Assessment Report of the Intergovernmental Panel on Climate Change (IPCC) [M]. Cambridge:Cambridge University Press,2001:180-245.
[138]蔡丽莎,陈先刚,郭颖,等.贵州省退耕还林工程碳汇潜力预测[J].浙江林学院学报,2009,26(5)：722-728
[139]蔡丽莎,陈先刚.贵州省退耕还林工程主要树种碳汇潜力预测[J].山东林业科技,2009,181(2)： 15-18
[140]陈先刚,赵晓惠,陆梅,等.四川省退耕还林工程林碳汇潜力研究[J].浙江林业科技,2009,29(5)：19-28
[141]陈先刚,张一平,詹卉.云南退耕还林工程林木生物质碳汇潜力[J].林业科学,2008,44(5)：24-30
[142]陈先刚,张一平,潘昌平.重庆市退耕还林工程林固碳潜力估算[J].中南林业科技大学学报, 2009,29(4)：7-15
[143]国务院发展研究中心.西部大开发指南——统计信息专辑[M].北京：中国社会科学出版社,2000,19-24
[144]国家退耕还林办分室.退耕还林指导与实践[M].北京：中国农业科学技术出版社,2003
[145]杨正礼.我国退耕还林研究进展与基本途径探讨[J].林业科学研究,2004,17(4)：512-518
[146]史良树.SPOT-5数据在退耕还林测中的应用研究——以山西省古交市嘉乐泉乡为例[D].北京：中国林业科学研究院,2004
[147]王晓光,王珠娜,余雪标,等.退耕还林生态效益评价指标体系研究[J].防护林科技,2006(11)：51-53.
[148]姚清亮,陆贵巧,杜剑,等.关于承德市退耕还林工程生态效益评价研究[J].河北农业大学学报,2009,32(6)：57-61
[149]周文渊,赵岩,郭建英,等.安定区退耕还林工程的生态效益评价[J].中国农学通报,2009,25(20)：115-120
[150]杨建波,王利.退耕还林生态效益评价方法[J].中国土地科学,2003,11(5)：54-58
[151]田大伦.杉木林生态系统定位研究方法[M].北京：科学出版社,2004
[152]张学权,胡庭兴,李伟,等.华西雨屏退耕地不同植被经营模式坡面径流和产沙特征分析[J].水土保持学报,2004,18(6)：27-33
[153]温仲明,焦峰,刘宝元,等.黄土高原森林草原区退耕地植物自然恢复与土壤养分变化[J].应用生态学,2005,16(11)：2025-2029
[154]张国斌,田大伦,方晰,等.湖南会同退耕还林不同造林模式下土壤有机碳分布特征[J].中南林业科技大学学报,2008,28(2)：8-12
[155]潘维俦,田大伦.森林生态系统第一性生产量的测定技术与方法[J].湖南林业科学,1981,(2)：1-12
[156]杨树,温雨金,刘鸿雁.内蒙古中部地区退耕还林还草后植被与土壤性状的变化[J].水土保持研究,2006,13(4)：143-145,149
[157]黄宇,汪思龙,冯宗炜,等.不同人工林生态系统林地土壤质量评价[J].应用生态学报,2004,15 (12)：2199-2205
[158]Acosta Mratine Martinez V, Reicher Z, Bischoff M, et al. The role of tree leaf mulch and nitrogen fertilizer on turf grass soilquality[J].Biolfertsoils,1999,29:55-61
[159]Whalley W R, Dumitru E, Dexter A R. Biological effects of soil compaction[J]. Soil Tillers,1995, 35:53-68
[160]Zheng Y S, Ding Y X. Effect of mixed forests of Chinese-fir and Tsoong's tree on soil properties[J].Pedosphere,1998,8 (2):161-168
[161]杨玉盛,俞新妥,邱仁辉.栽杉留阔模式生产力和土壤肥力的研究[J].林业科学,1999,35(4)： 9-13
[162]高雪松,邓良基,张世熔.不同利用方式与坡位土壤物理性质及养分特征分析[J].水土保持学报,2005,19(2)：53-60,79
[163]王涌清,孙昭荣,刘秀奇.潮土及盐化潮土中的微团聚体及有机质在各组微团聚体中的分布[J].土壤肥料,1983,19(4)：10-13
[164]唐炎林,邓晓保,李玉武,等.西双版纳不同林分土壤机械组成及其肥力比较[J].中南林业科技大学学报(自然科学版),2007,27(1)：70-76
[165]杨万勤,张健,胡庭兴,等.森林土壤生态学[M].成都：四川科学技术出版社,2006：335-341
[166]北京林学院主编.土壤学[M].北京：中国林业出版社,1982,98-117
[167]湖南省农业厅编著.湖南土壤[M].北京：农业出版社,1989
[168]徐成龙,林昌虎,何腾兵,等.黔中石漠化地区生态恢复过程中土壤养分变异特征[J].水土保持通报,2004,24(6)：22-29,89
[169]陈书玉.环境影响评价[M].北京：高等教育出版社,2002,160-162
[170]王云,魏复盛.土壤环境化学[M].北京：中国环境科学出版社,1995
[171]朱建军,崔保山,杨志峰,等.纵向岭谷区公路沿线土壤表层重金属空间分异特征[J].生态学报,2006,26(1)：146-153
[172]Adejuwon J O, Ekanade O. A comparison of soil properties under different land use types in a part of the Nigerian Cocoa Belt[J]. Catena,1988,15:319-331
[173]Lowery B, Swan J, Schumacher T, et al. Physical properties of selected soils by erosion class[J]. Soil Water Conserv.1995,50:306-311
[174]潘维俦,田大伦,文仕知,等.集水区内森林生态系统的养分分析[J].中南林学院学报,1988,8(2)：115-122
[175][美]F.B索尔兹伯里,C.罗斯.植物生理学[M].北京：科学出版社,1981
[176]黄健辉,陈灵灵.北京百花山附近杂灌丛的化学元素含量特征[J].植物生态学与地植物学学 报,1991,15(3)：224-232.
[177]刘茜,刘煊章,张昌剑.天然次生白栎林生物量与营养元素含量的研究[J].林业科学,1997,33(Sp2)：157-166
[178]蒋有绪.川西亚高山冷杉林枯枝落叶层的群落学作用[J].植物生态学与地植物丛刊,1981,6(2)：89-98
[179]张万儒,许本彤.山地森林土壤枯枝落叶层结构和功能研究[J].土壤学报,1990,27(2)：121-131
[180]陈堆全.木荷凋落物分解及对土壤作用规律的研究[J].福建林业科技,2001,28(2)：86-89
[181]余清发,温达志,张德强.鼎湖山南亚热带常绿阔叶林定位研究(Ⅷ)锥栗、黄果厚壳桂群落营养元素生物循环[A].见：中国科学院鼎湖山森林生态系统定位研究站、鼎湖山国家级级保护区管理处编.热带亚热带森林生态系统研究(第8集)[C].北京：气象出版社,1998
[182]蚁伟民,丁明懋,张祝平,等.鼎湖山黄果厚壳桂群落的凋落物及其氮素动态[J].植物生态学报,1994,18(3)：228-235
[183]潘瑞炽,董愚得编.植物生理学(第三版).北京：高等教育出版社,1995,32-40
[184]许振英.十多年来我国畜牧学科中微量元素研究.中国动物营养学报,1989,1(1)：1-9
[185]缪自基主编.微量元素的环境化学与生物影响[M].北京：中国环境科学出版社,1992
[186]刑廷铣,李丽立,彭艺.土壤—作物—动物生态体系中微量元素含量[J].生态学杂志,2000,19(2)：24-29
[187]Chapin F S. The Mineral Nutrition of wild plants[J]. Annu. Rev. Ecol. Syst,1980,11:233-260
[188]计维农.太湖流域主要粮食作物中19种元素背景值及其特征[J].环境科学学报,1987,7(1)：86-92
[189]杜荣.我国饲料中微量矿物质浅析[J].中国畜牧杂志,1989,25(4)：20-23
[190]佘崇祥.湖南红壤中微量元素的含量与分布[J].农业现代化研究,1994,增(1)：41-45
[191]许嘉琳,鲍子平,杨居荣,等.农作物中铅、镉、铜的化学形态[J].应用生态学报,1991,2(3)：244-248
[192]赵敏,周广胜.中国森林生态系统的植物碳贮量及其影响因子分析[J].地理科学,2004,24(1)：50-54
[193]Fang J, Chen A, Peng C, et al. Changes in forest biomass carbon storage in China between 1949 and 1998[J]. Science,2001,292:2320-2322.
[194]Zhang X O, Xu D Y. Potential carbon sequestration in China's forests[J]. Enviromental Science & Policy,2003,6:421-432.
[195]陈广生,田汉勤.土地利用／覆盖变化对陆地生态系统碳循环的影响[J].植物生态学报,2007,31(2)：189-204
[196]Andrews S S, Karlen D L, Cambardella C A. The soil management assessment framework:a quantitative soil quality evaluation method[J]. Soil Science Society of American Journal,2004,68: 1945-1962.
[197]张华,张甘霖,漆智平,等.热带地区农场尺度土壤质量现状的系统评价[J].土壤学报,2003,40(2)：186-193
[198]Jobbagy E G, Jackson R B. The vertical distribution of soil organic carbon and it's relation to climate and vegetation[J]. Ecological Application,2002,10(2):423-436.
[199]阮宏华,姜志林,高苏铭.苏南丘陵主要森林类型碳循环研究—含量与分布规律[J].生态学杂志,1997,16(6)：17-21
[200]方晰,田大伦,项文化.速生阶段杉木人工林碳素密度、贮量和分布[J].林业科学,2002,38(3)： 14-19
[201]马钦彦,陈遐林,王娟,等.华北主要森林类型建群种的含碳率分析[J].北京林业大学学报,2002,24(5/6)：96-100
[202]Zinn Y L, Resck D V S, da Silva J E. Soil organic carbon as affected by afforestation with Eucalyptus and Pinus in the Cerrado region of Brazil[J]. Forest Ecology and Management,2002,166: 285-294.
[203]Turner J, Lambert M. Change in organic carbon in forest plantation soils in eastern Australis[J]. Forest Ecology and Management,2000,133:231-247.
[204]吴建国,张小全,徐德应.土地利用变化对土壤有机碳贮量的影响[J].应用生态学报,2004,15(4)： 593-599
[205]田大伦著.马尾松和湿地松林生态系统结构与功能[M].北京：科学出版社,2005
[206]章继刚.创意农业：促进农民增收致富的新途径[J].改革与开放,2008, (7)：9-10
[207]袁红军,曹国璠,晏世强.退耕还林生态效益评价研究与展望[J].现代农业科技,2009,(2)：239-242
[208]李丕蓉,彭培好,朱琴,等.四川盆地周边地区退耕还林工程经济效益分析[J].国土资源科 技管理,2008,25(1)：20-23
[209]康文星,田大伦.杉木人工林采代表后水源涵养和固土保肥效益损失的评价[J].林业科学,2002,38(1)：111-115
[210]周冰冰,李忠魁.北京市森林资源价值[M].北京：中国林业出版社,2000
[211]http://www.cnenv.com/NewsShow.aspx?id=296
[212]薛达元,包浩生,李文华.长白山自然保护区森林生态系统间接经济价值评估[J].中国环境科学,1999,19(3)：247-252
[213]侯元兆,张佩昌,王琦.中国森林资源核算研究[M].北京：中国林业出版社,1995,134-136
[214]靳芳,鲁绍伟,余新晓,等.中国森林生态系统服务功能及其价值评价[J].应用生态学报,2005,16(8)：1531-1536
[215]余新晓,秦永肚,陈丽华,等.北京山地森林生态系统服务功能及其价值初步研究[J].生态学报,2002,22(5)：783-786
[216]薛达元.生物多样性经济价值评估——长白山自然保护区案例研究[M].北京：中国环境科学出版社,1997