Analysis of dynamic soil erosion in semi-arid and semi-humid areas in China: A case study in Hulunbeir, Inner Mongolia

As a case study on analysis of soil erosion change, in Hulunbeir, Inner Mongolia, China, was once one of the most severely eroded regions in semi-arid and semi-humid China. However, its soil erosion is becoming a matter of concern for more and more people in recent years. The main body of vegetation is Daxinganling virgin forests and Hulunbeir grassland, However, large areas of forest were destroyed and excessive grazing in pastureland, which resulted in the increase of soil erosion. Fortunately, the government has taken corresponding measures to prevention and control soil erosion in recent years. In this study, based on TM imagines, and employing ArcGIS 9.3 technique and empirical Revised Universal Soil Loss Equation (RUSLE) model, this paper studied the dynamics of soil erosion at the Hulunbeir from 1995 to 2005 years. Use of the Markov model to predicted the soil erosion in Hulunbeir next 15 years. The results show that the main erosion types arte the tiny degree erosion as clue, above the light degree erosion is 10 percent of Hulunbeir area in the past 10 years from 1995 to 2005. The net decrease of the tiny degree erosion in 2000 is 534.33km² compared with 1995, and the area of above the light degree erosion increased 580.02km² from 1995 to 2000. This explains that the soil erosion of Hulunbeir area shows the increasing tendency in the past 5 years. The net increased of the tiny degree erosion in 2005 is 8326.69km² compared with 2000, and the area of above the light degree erosion is decreased by 8360.54km². This shows the decreasing tendency of the soil erosion intention in Hulunbeir region. And comparing to 2000 year, the soil erosion have undergone great changes. Then, the development and the future tendency of soil erosion in 2010, 2015 and 2020 year that uesed simulated with Markov process, the soil erosion intensity for Hulunbeir area will be alleviated, among which above the light degree erosion land area wil- be decreased by 5.4%, 4.4% and 3.9% proportion to that of 2005. Indicating that soil erosion had been substantially controlled.