Study on water conservation value assessment of land ecosystems in Guanzhong-Tianshui Economic Zone

The research obtained the land use map by using Landsat remote sensing data of Guanzhong-Tianshui Economic Zone, which were around September in 1980, 2000, 2005 and 2010. With the 30-year annual average precipitation data, the article using precipitation storage capacity method I, analyzed the land-use change of three time periods in 1980-2000, 2000-2005, 2005-2010, calculated the value of water conservation and got its spatial distribution of land ecosystem in Guanzhong-Tianshui Economic Zone. In space, with the rise of latitude and decrease of longitude, the per unit area of water conservation quantity is gradually reduced. The per unit area of water conservation quantity in the large cities distribution of Guanzhong region and Tianshui area is less than Qinling Mountains. Water conservation value reached up to 4.89 billion yuan in 1980, 4.87 billion yuan in 2000, 4.86 billion yuan in 2005, and 4.84 billion yuan in 2010.