FOREST DECLINE AND THE GLOBAL CLIMATE CHANGE Effects of Temperature on Photosynthetic Rates in Korean Fir (Abies koreana) between Healthy and Dieback Population ATMOSPHERIC SO2 POLLUTION AND DECLINE OF MASSON PINE(PINUS MSSONIANA)FOREST IN NANSHAN, CHONGQING THE STRUCTURAL CHANGES OF CUNNINGHAMIA LANCEOLATA HOOK. COMMUNITY EXPOSED IN COMPOUND-POLLUTED ENVIRONMENT FOR A LONG TERM STUDY ON THE DECLINE STATE OF THE ABIES FABRI FOREST IN EMEI MOUNTAIN