Land Desertification Evaluation on the Basis of Quantitative Remote Sensing in Songnen Plain China

摘要

This paper based MODIS image and adopted remote sensing quantitative retrieval technique to build the land desertification evaluation index system which are made up with vegetation fractional coverage (FVC), modified soil-adjusted vegetation index (MSAVI), NPP, land surface temperature (LST) and temperature vegetation dryness index (TVDI). The author adopted the gray correlation degree model to carry out quantitative evaluation on land desertification situation from 2002 to 2005 in Songnen Plain. The results indicated that the area of non-desertification in Songnen Plain decreased year by year in 2002-2004, the proportion dropped from 83.29% to 75.45%.The most severe desertification, severe desertification and slight desertification areas increased year by year, with an average annual growth rate 21.94%,21.06% and 18.21% respectively. The characteristics of land desertification in Songnen Plain are the areas and degree increasing yearly, distribution trend centralizing and rainfall effect prominently.