Spatial And Temporal Characteristice Of Soil Erosion And Ites Main Driving Forces In The Hilly Red Soilregion Of South China

Soil erosion is one of the most serious ecological problems around the world,and its sustainability of land productivity and environment constitute the serious harm.The formation mechanism of soil erosion and the change process is very complex,natural and human activity can and a series of driving force factors of soil erosion intensity and distribution of a certain impact.Insight into different driving force factors impact on the formation mechanism and the change process of soil erosion and mining of the interaction between the different driving factors,the effective development of comprehensive control of soil and water loss,land resources reasonable planning and management,construction of ecological civilization is of great significance.In this paper,the southern red soil of low hil y land as the research object,based on Chinese soil loss equation(CSLE)from 1985 to 2015 was calculated soil erosion modulus in the study area.At the same time combined with nuclear density analysis and k-means clustering,this paper discusses the spatial and temporal variations of soil erosion;And on this basis,the use of structural equation model,calculated the natural and human factors driving force of soil erosion.Main conclusions are as follows:(1)The study area soil erosion area from the point of interannual variability,the soil erosion intensity in 1985-2015 has obvious fluctuations,and overall a downward trend.The highest average soil erosion modulus for 1985 of 10.1 t/(hm~2 a.),min.2015 of 6.4 t/(hm~2,a).10 years from 1985 to 1995,small variations in erosion area,sharply rising trend from1995 to 2000,2000 soil erosion area,the largest since the soil erosion area is declining,fal ing faster after 2010.(2)In the study of the contribution index to soil erosion change,it can be seen that biological measure factors play a greater role in the change of soil erosion,followed by engineering measure factors,and til age measure factors have the smal est effect on the change of soil erosion in all regions.Among them,from 1985 to 1995,each measure factor had a positive effect on the reduction of soil erosion;from 1995 to 2000,each measure factor had a positive effect on the increase of soil erosion;after 2000,each measure factor had an obvious positive effect on the reduction of soil erosion,which greatly al eviated the degree of soil erosion in the study area.(3)In the analysis of the driving force of the key water erosion factors,Each stage of the natural factors and artificial afforestation and urban development of biological agents in the measures the average contribution rate of 46.1%,35.4%and 18.5%.The industrial structure,soil conservation and social development of engineering measures factor contribution rate of distinguish to an average of 63.1%,19.1%and 17.8%.Agricultural development and cultivation measures to cultivate the average contribution rate of distinguish between 68.1%and 31.9%.From 1985 to 1990,the implementation of the household contract responsibility system in rural areas increased the trend of farming measures.From 1990 to 2000,there was no significant change in each measure factor.From2000 to 2015,with the implementation of projects such as returning farmland to forest,"Chang Zhi"project and ecological civilization construction,the factors of various measures showed an obvious trend of negative growth.