STUDY ON SEASONAL DYNAMICS OF ABOVEGROUND BIOMASS AND GROWTH RATE OF DEYEUXIA ANGUSTIFOLIA POPULATION IN MARSH MEADOW ON SANJIANG PLAIN STUDY ON THE QUANTITY CHARCTERISTICS SEASONAL DYNAMICS OF ANEUROLEPIDIUM CHINESE+HERBS COMMUNITY Seasonal Dynamics of Litter in a Headwater Stream of Riparian Forest in Xiangxi River Catchment Seasonal dynamics in soil microbial biomass and enzymatic activities under different alpine brushlands of the Eastern Qilian Mountains