Responses of Vegetation Changes in Growing Season to Precipitation in Yarlung Zangbo River Basin

ZHANG Jiaqi;REN Zhiyuan;College of Tourism and Environmental Sciences,Shaanxi Normal University;

NDVI in growing season;;empirical orthogonal functions;;singular value decomposition;;Yarlung Zangbo River Basin

Using empirical orthogonal functions(EOF)and singular value decomposition(SVD),this paper analyzed the temporal and spatial distribution characteristics and the spatial-temporal correlation between vegetation cover in growing season and precipitation in Yarlung Zangbo River Basin in 2000—2010.The results are shown as follows.During the period of 11 years,the characteristics are becoming more significant in July,August and September each year,and the spatial distribution of the trends is becoming ever more obvious in recent years.The contribution rate of the main mode of vegetation reached up to 55.7%.The vegetation coverage in eastern millin wide area is higher than other regions,and time coefficient oscillation cycle is obvious and presents the rising trend.The coupling mode relationship between vegetation cover and wet season precipitation shows a positive correlation,and the highest contribution rate is 61.8%.Monsoon climate has the direct influence on vegetation cover,the landscape factors and the land use type characteristics were the secondary factors affecting the vegetation cover.