The evergreen broad-leaved forests of Yunnan are classified into three vegetation sub-types: monsoon evergreen broad-leaved forest (found on tropical mountains in southern Yunnan), semi-wet evergreen broad-leaved forest (found mainly on plateaus), and mid montane wet evergreen broad-leaved forest (found on upper mountains in central Yunnan). Prof. ZHU Hua of Xishuangbanna Tropical Botanical Garden (XTBG) studied the floristic composition and biogeography of the three subtypes of the evergreen broad-leaved forests and revealed their diversification and divergence. He got the study published in Phytotaxa. Prof. ZHU Hua found that for the three main evergreen broad-leaved forests in Yunnan, shared species-rich families tended to have cosmopolitan distributions, but families with less species belonged to the various other distribution types. Importantly, the patterns of distribution types at the generic level showed similarities between the semi-wet evergreen broad-leaved forest (SWEB) and the upper montane evergreen broad-leaved forest (LMEB), but were conspicuously different in the lower montane evergreen broad-leaved forest (LMEB). For the generic level, tropical distribution elements comprised 45% and 44% of the SWEB and UMEB floras and temperate distributed elements contributed 46% and 48 to the SWEB and UMEB totals. Additionally, northern temperate distributed genera made up the highest ratio in generic distribution types (18% in the SWEB and 20% in the UMEB). |