Study on the Characteristics of Alien Invasive Plants of Wetland in Yunnan

Based on the field survey of invasive plant of wetland in Yunnan province,it was found out that there were 70 alien invasive plants belonging to 54 genera,24 families. They originated from 5 continents,and 47 species( 67. 1 %) were from the American Continent. The invasive route were mainly introduced by human,accounting for 95. 7 %,and most of alien invasive plants were hygrophytes according to water ecotype,and were herbs according to life-form and were seed propagation according to reproduction type. The alien invasive plants by asexual reproduction expanded very fast which caused higher damages. The alien invasive plants were widely distributed in the wetland of 129 counties of 16 prefectures or municipalities in Yunnan,among of which 43 species( 61. 5 %) were distributed in the whole province.