INTERSPECIFIC RELATIONSHIPS AND ENVIRONMENTAL INTERPRETATION OF THE MAIN TREE SPECIES IN THE FOREST COMMUNITIES OF ZHUWEIGOU IN LISHAN MOUNTAIN NATURE RESERVE Interspecific Relationships among the Dominant Weeds Species of Tobacco Field in Guizhou Province Analysis of Interspecific Relationships among the Dominant Populations of Platycladus orientalis Communities in Yanshan Nature Reserve in Shanxi The effect of different grazing systems on aboveground biomass and interspecific relationships in desert steppe Interspecific relations of the wild community of Artemisia annua and their responses to flooding disturbance Intraspecific differentiation of Pleurospermum hookeri (Apiaceae), and its interspecific relationships with two close relatives in the genus Pleurospermum