【作者】 任改；

【导师】 张洪江；

【作者基本信息】 北京林业大学 ， 水土保持与荒漠化防治， 2010， 硕士

【摘要】 重庆(三峡库区)由于特殊的自然环境和人为活动的影响,存在水土流失、地质灾害等一系列生态环境问题。虽然国家、地方各级政府加强了生态环境建设,但是存在很多问题,尤其是水土保持型植被的构建。重庆四面山位于三峡工程库区尾端,具有丰富的自然资源,然而当地旅游资源的开发和农民不合理的采伐、放牧以及开垦,使该区域的森林植被严重破坏,水土流失严重,成为三峡库区泥沙来源的主要区域之一。因此,在该区开展主要植物群落土壤抗侵蚀性规律的研究,对于该区土壤侵蚀的防治、三峡库区水土保持型植被构建和优化具有重要意义。结合国家“十一五”科技攻关课题“三峡库区低山丘陵区水土保持型植被构建技术试验与示范”,以重庆四面山主要植物群落为对象,采用土粒浸水实验、原状土冲刷水槽法以及室内土壤物理化学性质分析法,从土壤抗蚀性、抗冲性两个方面着手,全面系统分析了土壤抗侵蚀性的特征及其影响因素,并采用理想点综合分析评价了土壤抗侵蚀性。主要结论如下：(1)不同植物群落土壤抗侵蚀性及其动态变化和垂直变化存在显著差异。在土壤抗蚀性方面表现出常绿落叶阔叶混交林(85.0%)最好,暖性竹林(62.0%)最差；在土壤抗冲性方面表现出暖性竹林(28.94 L·min/g)最好,温性针叶林(5.56 L·min/g)最差。植物群落土壤的抗蚀性与时间呈二次多项式函数关系逐渐降低,而抗冲性与时间呈指数函数逐渐增大。在同一土壤剖面,不同层次土壤的抗蚀性和抗冲性均随土壤深度的增加呈下降趋势。(2)不同植物群落土壤抗侵蚀性受其物理、化学性质的影响有显著差异,经多元回归分析,植物群落土壤抗蚀性与非毛管孔隙度(X3)、极粗砂粒(X5,2-1mm)含量和粉粒(X1o,0.05-0.002mm)含量3个物理指标呈线性关系,其方程为：S=104.785+1.279X3-5.428X5-1.849X10与化学指标全P含量(X14)、速效K含量(X17)呈线性关系,其方程为：S=10.480+7.671X14-1.067X17土壤抗冲性与土壤密度(X1)、中砂粒(X7,0.5-0.25mm)含量、细砂粒(X8,0.25-0.05mm)含量、粉粒(X10,0.05-0.002mm)含量和黏粒(X11,<0.002 mm)含量(%)4个物理指标呈线性关系,其方程为：C=-62.830-12.824X1+2.928X7+0.649X8+2.182X10+0.822X11与有机质含量(X12)呈线性关系,其方程为：C=-2.572+0.291X12(3)植物群落土壤的抗蚀性和抗冲性之间具有密切的关系,经灰色关联分析二者关联度为0.778。经坐标综合评定法分析得到土壤抗侵蚀性强弱依次为：暖性竹林的最好,坐标综合值为0.190,常绿阔叶林(0.448)、落叶阔叶林(0.585)和常绿落叶阔叶混交林(0.618)居中,温性针叶林和暖性针叶林最差,坐标综合值分别为0.732、0.626。更多还原

【Abstract】 Because of special natural environment and human activities, there are many ecological and environmental problems in Chongqing (Three Gorges Reservoir Area), such as soil and water loss, geological disasters. Although ecological construction has been promoted by our country and government, many problems exist, especially for the vegetation construction. Simian Mountain is located in the end of Three Gorges area. It has rich natural resources, however, the development of tourism resource, cutting, grazing and reclaiming of peasants, has let lots of trees be damaged, and made severe soil and water loss. This area has become the main source of sediment to the three Gorges Reservoir area. So research on soil anti-erosion in this area of different plant communities is significant for soil erosion control and vegetation construction in the Three Gorges Reservoir area.Associated with the national eleventh-five year plan of state key task of scientific and technological research "Technology Research and Demonstration of Vegetation Construction with Soil and Water conservation in Three Gorges Reservoir Area, Yangtse River Basin ", based on the experiments of dispersion of soil particals in water, scourry and analysis of soil physical and chemical characteristics, this study analyzed the soil anti-erosion characteristics and its influenceing factors of the main plant communities in Simian mountain. The main conclusions are as follows:(1)The soil anti-erosion characteristics are obvious different in different plant communities. Evergreen and deciduous forest community soil has the best soil anti-erodibility (85.0%), and the soil anti-erodibility of warm bamboo groves is the worst (62.0%). Warm bamboo groves soil has the best anti-scouribility (28.94 L-min/g), and the soil anti-scouribility of hurmoral coniferous forests is the worst (5.56 L·min/g). The soil anti-erodibility decreases with the increase the duration of rainfall. The soil anti-scouribility is exponentially correlated to time. The soil anti-erodibility and soil anti-scouribility decreases with depth.(2) Physical and chemical soil characteristics play a difference role in the soil anti-erosion characteristics of different plant communities. Soil anti-erodibility is linearly correlated to non-capillary pores(X3), content of rough sand(X5,2-1mm) and powdery(X10,0.05-0.002mm). The equation is as following: S=104.785+1.279X3-5.428X5-1.849X10 It is also linearly correlated to the content of total phosphorus(X14) and rapid available potassium(X17). The equation is:S=10.480+7.671X14-1.067X17Soil anti-scouribility is linearly related to the soil density(X1), the content of medium sand(X7,0.5-0.25mm), the small sand(X8,0.25-0.05mm), powdery(X10,0.05-0.002mm), and clay(X11,<0.002 mm). The equation is: C=-62.830-12.824X1+2.928X7+0.649X8+2.182X,0+0.822X11 It is also linearly correlated to the organic matter content (X12). Tts equation is:C=-2.572+0.291X12(3) Soil anti-erodibility has a close relationship with anti-scouribility of plant communities. The soil anti-erosion capacity of different plant communities were evaluated by comprehensive coordinate method, and the order is as follows:warm bamboo groves (0.109), evergreen broad-leaved forest (0.448), deciduous broad-leaved forest (0.585), evergreen and deciduous forest community (0.618), hurmoral coniferous forests (0.732), warm coniferous forests (0.626).更多还原