Life Table and Dynamic Analysis of Fagus hayatae Population in Micangshan Nature Reserve,Sichuan Province,China Population quantitative characteristics and dynamics of rare and endangered plant Davidia involucrata in Hunan Province Associations between weather factors and the spring migration of the horned gall aphid, Schlechtendalia chinensis POPULATION QUANTITATIVE CHARACTERISTICS AND DYNAMICS OF RARE AND ENDANGERED TSUGA TCHEKIANGENSIS IN JIULONGSHAN NATURE RESERVE OF CHINA