An Analysis of Interspecific Associations in Secondary Succession Forest Communities in Heishiding Natural Reserve, Guangdong Province Dynamics of species diversity and interspecific associations of herbaceous plants in a Pinus Tabulaeformis forest on a sandy site in Chifeng, China Study on Interspecific Associations of Natural Nitraria tangtorum Population and Its Main Companion Species in Ulanbuh Desert Interspec ies Connection of Dom inant Tree Spec ies inCepha lotaxus fortune i Commun ities Analysis of interspecific associations among major tree species in three forest communities on the north slope of Changbai Mountain