Abstract [Background] Changting County is one of the most serious counties in the area of granite red soil region in the south of our country, where is also very typical and representative because its soil and water loss has the characteristics of long history, wide area, large degree, and great damage. [Methods] In order to dynamically monitor the spatio-temporal changes of recent years'soil erosion in Changting County that is the demonstration area of soil and water loss management and ecological civilization construction, we used the USLE model to quantitatively estimate the changing situations of this county's soil and water loss in recent 25 years, according to the remote sensing data of 9 periods'Landsat series from 1988 to 2013, and using the topography, soil and meteorological hydrological literatures and with the field trips. [Results]The results showed that,the situation of Changting County's vegetation coverage was fine generally. The areas of higher vegetation coverage were mainly distributed around the county, and the central areas along two sides of Tingjiang River had lower vegetation coverage due to the serious situation of soil and water loss. The vegetation coverage showed a downward trend generally from 1988 to 1994, and became the worst in 1994. During the periods of 1994 to 2003, the situations of vegetation coverage in the most area of this county were improved obviously, especially that of the villages and towns in the middle areas. After 2003, the vegetation coverage changed little in the western areas, but in Cewu, Hetian, Sanzhou, and Zhuotian and some other towns, it increased greatly. The situations of the soil and water loss in Changting's most areas were mild, and the serious areas mainly distributed in Changting's middle area and southern towns. Especially, Hetian Town, Zhuotian Town, Sanzhou Township and Cewu Township were the most serious areas suffering from soil erosion. The results of remote sensing dynamic monitoring during 1988 to 2013 showed that the whole situation of the soil and water loss was improved significantly. It became worse and worse from 1988 to1994, and was at the worst in 1994. Later the situation was improved year by year after 1994, and especially after 2003, the both situations of the vegetation cover and middle area's soil and water loss in Changting got better. [Conclusions] The analysis mentioned above proves that using the USLE model to estimate the soil erosion modulus of Changting County may have high accurate and reliable results, which really reflects the temporal and spatial changes of this county's soil erosion over the last 25 years. The results show the changing situations and the treatment effect of the soil and water loss in Changting County, as well as provide a scientific basis to understand its current present situations and orient the corresponding treatment directions.
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