美国北卡罗来纳州外来入侵植物入侵性、克隆性及地理起源研究

Invasiveness,clonality and geographic origin of alien invasive plant in North Carolina of America

对美国北卡罗来纳州112种外来入侵植物进行了研究。结果表明:入侵性最强的物种占24.1%,较强的物种占44.6%,较弱的物种占31.3%。克隆植物有67种,占入侵植物总数59.8%,且繁殖方式以匍匐茎型和分蘖型为主。1年生或2年生草本、多年生草本、水生草本、乔木、灌木、藤本和竹类植物分别占入侵植物总数的23.2%、20.5%、8.9%、7.1%、23.2%、15.2%和1.8%,其中克隆植物所占比例分别为46.2%、82.6%、100%、62.5%、34.6%、58.8%和100%。随着入侵性的增强,在3个危害等级中来自亚洲的入侵植物比例依次为45.7%、66.0%和74.1%;来自欧洲的入侵植物比例依次为45.7%、30.0%和14.8%。上述结果表明,北卡罗来纳州入侵植物的入侵性可能与其克隆性具有较强的相关性,其地理起源多来自于亚洲和欧洲。

To date,few studies have addressed the relationship of clonality and invasiveness of alien invasive plants in large geographical scale.The 112 alien invasive plants in North Carolina of America were analyzed.The results showed that the percentage of the strongest invasiveness plants,the stronger invasiveness plants,the weaker invasiveness plants in all invasive plants are 24.1%,44.6% and 31.3%.There are 67 invasive clonal plants（59.8%）,whose mainly reproductive types were stolon and tiller.The percentages of annual or biennial herbs,perennial herbs,aquatic herbs,tree,shrub,vine and bamboo in total invasive plants are 23.2 %,20.5%,8.9%,7.1%,23.2%,15.2% and 1.8%,with clonal plants accounting for 46.2%,82.6%,100%,62.5%,34.6%,58.8% and 100%,respectively.With the increase of invasiveness,the percentages of invasive plant originated from Asia are 45.7%,66% and 74.1% in three ranks,and those originated from Europe are 45.7%,30% and 14.8%.Data mentioned above indicated that clonality of the invasive plants in North Carolina may be contributed significantly to their invasiveness,and Asia and Europe were the primarily geographical origin of these alien invasive plants.