Dynamicevolution And Simulation Of Soil Erosion In The Mountainous Area Of Western Fujian

Soil erosion will deepen the desertification of the soil and make the soil degenerate which will not only leads to the instability of the ecological environment but also threatens the survival and development of human beings.The problem of soil erosion in Ninghua county has been happening over a hundred years.The study area which selected in this paper is located in the two villages that have the most serious soil erosion problem in Ninghua County,therefore the study of soil erosion in the region is representative.This paper takes the watershed of Changfengli-Shibixi in Ninghua county as study area,and uses"3S" technology and software such as Matlab,Excel,Fragstats etc.,to evaluate the regional soil erosion by using the RUSLE model,and then establish the soil erosion database based on the RUSLE model.Based on the analysis of the temporal and spatial evolution of soil erosion intensity,the relationship analysis with the related factors and the analysis of landscape,the process and law of soil erosion evolution are understood.Using the function of genetic algorithm,neural network and cellular automata that optimization and spatial dynamic simulation to construct the soil erosion prediction model in the study area.And use the prediction model to calculate the soil erosion of the study area in 2019,in order to provide scientific basis for the comprehensive harnessing in Changfengli-Shibixi watershed.The results show that the soil erosion in the study area is mainly concentrated in the hilly and low mountain areas with an elevation of 200m-800m and a slope less than 15 degrees.The soil erosion rate in the bare land,the grassland and the garden is high.The micro erosion landscape in the study area is gradually becoming flaky,the degree of fragmentation is reduced,and the landscape type is gradually developing to a single or disequilibrium direction.Through the construction and application of soil erosion prediction model,it found that soil erosion in the study area in 2019 has been well controlled,the area of intensity erosion and intensity above erosion is obviously reduced.