supported by the National Basic Research Program of China(2010CB951304-4);the National Natural Sciences Foundation of China(31301862,31370532);the Fund for Excellent Young Scholars of Northeast Institute of Geography and Agroecology,Chinese Academy of Sciences(DLSYQ 13003)
supported by Knowledge Innovation Programs of Chinese Academy of Sciences ( KZCX2-YW -BR-16);National Basic Research Program of China ( 973 Program,2010CB951304-4);the National Natural Science Foundation of China ( 40901036,41171047)