Desertification Of Vegetation Dynamic Change Research

Chahanwusu River Basin located in the highland areas of the desertification in the region with the high altitude, low temperature, soil salinization, and other features, to study the dynamic changes of desertification in the basin is of great significance for alpine vegetation recovery. Based on the basin meteorological data10years in precipitation, analysis the temperature of the year, inter-annual variation; based on the MODIS/NDVI, the DEM remote sensing data, analysis of the watershed vegetation in time and space to the dynamic changes in status and change in trend; the recovery of the vegetation in fencing and the intrinsic relationship between the MODIS/NDVI and meteorological data; linear regression model was constructed based on the TM/NDVI and field measurements.The analysis of meteorological data show that the watershed rainfall and temperature characteristics for the same period of rain and heat, summer rainfall accounted for more than70%of annual rainfall while the temperature is relatively high, the average annual rainfall and temperature are slowly increasing rend. MODIS/NDVI data analysis shows that the basin overall vegetation coverage is not high and the vegetation improved significantly concentrated in the river downstream tributaries around in the upstream parts of sporadic. The vegetation in fencing areas recovers affect. Analysis of the Relationship between NDVI and meteorological factors, rainfall and temperature are the main factors that affect the watershed vegetation, temperature and NDVI values were negative, highly significant correlation. Expression through photography inversion of vegetation coverage to build a linear regression model equation as: fc=195*NDVI+5.6024(fc is the coverage)The verification showed that the model for the medium and low vegetation coverage has better prediction.