Assessment Of Typical Small Watershed Ecosystem Health In The Hilly And Mountain Region Of Southern Jiangsu Province, China

Based on the PSR (Pressure–State–Response) model and the regional characteristics ofsmall watershed in the study area, the article established the index system for assessment, andused the BP neural network method to assess the ecosystem health of the small watershed namedSilong, Zhujiashan and Zhumen as examples. In the process, with the aid of remote sensing andgeographic information system technology, through analyzing the change tendency of smallwatershed soil erosion modulus and landscape patterns, the value of water and soil loss areaproportion, soil erosion modulus, land reclamation index, the index of development of smallwatershed, the NDVI index, landscape diversity index, landscape fragmentation index, the forestcoverage rate and so on was obtained. The research conclusion of this article is as follows:1. The intensity of soil erosion in Silong, Zhujiashan and Zhumen small watershed weregiven priority to mild erosion. Changing trend of soil erosion modulus the in the three smallwatershed were consistent:2006is the lowest, the highest was in2010, and the2000was in themiddle. This variation trend is in accordance with the rainfall erosion force factor R.2. Due to the transfer of land use types, the major land use types of Silong, Zhujiashan andZhumen small watershed are cultivated land and forest land. In2000,2006and2010, a variationfeature of the three stages was mainly unused land transfers into cultivated land and forest land,and cultivated land transfers to forest land transfer. Among them, the area of cultivated landtransfers into forest from2006to2010is larger than from2000to2006, this tendency isaccording with the national policy of returning farmland to forest gradually.3. Based on PSR conceptual model and the BP neural network method to establish theevaluation model, and through the data standardization, the article implements the quantitativeassessment of small watershed ecosystem health degree. On the analysis of social economic andnatural conditions of small watershed in Jiangning district, and according to the informationobtained, applying the advanced technologies, RS, GIS, ENVI and Matlab, etc., the articlecomprehensively and objectively got a comprehensive judgement and description of smallwatershed ecosystem through a series of qualitative and quantitative analysis. And extract smallwatershed ecosystem health assessment index of the Silong, Zhujiashan and Zhumen smallwatershed, putting forward the principle of selecting assessment index in the study area, and hasset up a reasonable assessment index system, using the BP neural network, and the structure is ascientific and reasonable assessment model for small watershed ecosystem health. In addition,the analysis of soil erosion modulus and the evolution trend of land use landscape pattern couldprovide beneficial references to the assessment of small watershed ecosystem health.