中文摘要：

据调查分析，杭州地区共有63种外来陆生植物和5种外来水生植物。陆生入侵植物中菊科种类最多，占入侵陆生植物的30．16％；5种入侵水生植物分属不同的5个科。原产美洲的外来入侵陆生植物43种，占入侵陆生植物68．25％；来自欧洲7种，占11．11％；来自亚洲其他地区6种，占9．52％；来自欧亚大陆和非洲的各3种，各占4．76％；来自热带亚洲1种，占1．60％。5种外来入侵水生植物全部来自美洲。有意引进的入侵陆生植物占陆生入侵植物的44．44％，无意引进的占55．56％。有意引进的入侵陆生植物通过人工引种、农作活动、带土苗木及鸟类传播扩散；无意引进的通过自然扩散、农作活动等途径扩散。5种外来入侵水生植物全部为有意引进，人工引种加速其扩散。外来入侵陆生植物多数是有害杂草，充当病虫害寄主植物，导致作物减产，影响生物多样性，一些植物有毒，危害人类健康。外来入侵水生植物常形成优势群落，影响排灌、通航，为蚊蝇提供寄生场所。加强栓疫，有效控制，强化研究，注重宣传和部门合作，建立防治和管理长效机制是应对入侵植物的重要策略。

英文摘要：

Totally 63 terrestrial inva- sive plant species and 5 aquatic invasive plant species were identified in Hangzhou district by investigation and analysis. The numbers of compositae plants among the terrestrial invasive plant species were the largest, account- ing for 30.16%, and the 5 aquatic invasive plant species belonged to different families. About 43 kinds of terrestrial in- vasive plant species came from America, making up 68.25%, and 7 kinds from Europe, 6 kinds from other parts of Asia districts, 3 kinds from Eurasia, 3 kinds from Africa, 1 kind from tropic Asia, ac- counting for 11.11%, 9.52%, 4.76%, 4.76% and 1.60%, respectively. Five aquatic invasive plant species were all from America.The percentage of inten- tional introduction alien plants account- ed for 44.44% in terrestrial invasive plant species, meanwhile, the percentage of unintentional introduction alien plants made up 55.56%. The intentional intro- duction terrestrial invasive plant species diffused through artificial introduction, farming activities, soil of nursery stock and bird＇ s carriage. Wherease, the unin- tentional introduction terrestrial invasiveplant species were spread by natural force and farming activities. All of the 5 aquatic invasive plant species were intro- duced by intentionally and the subse- quent introduction precipitated further proliferation. Most of terrestrial invasive plant species were the pernicious weeds, acting as the host of disease and insects, causing crop yield loss, leading biodiver- sity deprivation. Some of the terrestrial invasive plant species were poisonous and harm to human health. The aquatic invasive plant species constantly form advantageous population, affecting irri- gation and navigation, providing conve- nient places for flies and mosquitoes. In- tensifying quarantine inspection, consoli- dating control, strengthening research, paying more attention on propagation and cooperation among different depart- ments, setting up a long mechanism of prevention and management were the important strate