Spatial and temporal variation of soil erosion under different land uses in the Three Gorges Reservoir Region
Liu Ting,Shao Jing'an
1. College of Geographical Science, Chongqing Normal University, 400047,Chongqing, China;
2. Key Laboratory of Surface Process and Environment Remote Sensing in the Three Gorges Reservoir Area, 400047, Chongqing, China
[ Background ] Soil erosion is an important cause of soil nutrient loss, river channel sedimentation and many other ecological environment problems in the Three Gorges Reservoir Region. And severe soil loss in the Three Gorges Reservoir Region is in a widespread. [Methods] Taking the Reservoir Region as the study area, based on Geographical Information System, the Revised Universal Soil Loss Equation(RUSLE) was used to calculate the soil erosion of the five years, 1990, 1995, 2000, 2005 and 2010, in the Three Gorges Reservoir Region. ANOVA was used to analyze the significant impact on soil erosion in different land use. In addition, quantitative analysis was used to investigate the temporal and spatial variation of soil erosion intensity from 1990 to 2010; then the spatial distribution rules and spatial temporal characteristic of soil erosion under the different types of land use were studied.And all of above aimed to provide the supports for the sustainable development of the Three Gorges Reservoir Region. [ Results] During the period of 1990—2010, the value of average soil erosion modulus and the amount of soil erosion in the Three Gorges Reservoir Region were generally in a decreasing trend with the amount of 183.564 507 million tons, and it was graded as medium eroded area, in 2005 there was a certain degree of rebound with 19 282.74 million tons. From space, the slight and light erosion were the most widely distributed grades of soil erosion in this study area. The annual modulus of soil erosion of six different land use types in the same year was as: dry farmland > grassland > forestland > unused land > paddy field > construction land; one-way ANOVA revealed the soil erosion under different land use patterns, with a very significant difference,and there was solid difference in contribution rate of soil erosion by different kinds of land uses. The area of slight erosion in all 6 land use types gradually increased. Concurrently, erosion areas in moderate-and higher-erosion level transferred to the lower level at varying degree. [Conclusions] These above findings demonstrate that with returning farmland into forest and grass as well as large transferring of rural labor, the soil erosion in the Three Gorges Reservoir Region shows an improving trend as a whole, but the governance work in some parts of the Region still needs to be strengthened. The result of this study will be helpful to establish the quantitative relationship between land use and soil erosion, and also helpful in the adjustment of land use type in the future.
刘婷1,邵景安12. 三峡库区不同土地利用背景下的土壤侵蚀时空变化及其分布规律[J]. 中国水土保持科学, 2016, 14(3): 1-9.
Liu Ting,Shao Jing'an. Spatial and temporal variation of soil erosion under different land uses in the Three Gorges Reservoir Region. SSWC, 2016, 14(3): 1-9.