Study On The Impact Of Returning Farmland To Forest On Vegetation Distribution In Luoyugou Watershed With RS Techniques

摘要

Returning farmland to forests is a project to improve the ecological environment and promote sustainable development in our country that has a practical and historical significance. NDVI（Normalized Difference Vegetation Index）is an important parameter to reflect the vegetation growth and nutrition information. To some extent, it is positively correlated with the vegetation cover. In this paper, NDVI of Luoyugou watershed was extracted from the 2008 year's ETM image. Then terrain analysis (elevation, slope, aspect)was done combining with DEM (digitalized elevation model)with resolution of 1:500.The results showed that: The biggest change of NDVI located between 1400 and 1800 meters. The area of NDVI between 0 and 0.2 is reducing, but that 0.2-0.6 is contrary; there is the most obvious changes in NDVI on the slope more than 25 degree, vegetation coverage increased greatly. The NDVI changes have a same trend on the aspect, shifting from low to high vegetation coverage. These features are related with the special landscape of Luoyugou watershed and human activities. It will provide reference for the ecological construction and Soil and Water Conservation in Luoyugou watershed.