平原河网地区滨岸带外来植物入侵现状及影响研究——以上海青浦区为例

Status and impacts of alien plants invasion of the riparian zone in plain river network area:A case study in Qingpu district,Shanghai

河流滨岸带作为一种典型的开放系统,在受到外界干扰的条件下极易被外来植物所入侵并受到严重影响。以上海青浦区为例,通过对河流滨岸带生态系统入侵植物分布及现状调查,以及对两种入侵植物:白花三叶草(Trifolium repens)和加拿大一枝黄花(Solidago canadensis)群落的物种多样性及其土壤特性的实证研究,探讨外来植物入侵对河流滨岸带生态系统造成的影响。结果表明:目前该地区河流滨岸带外来入侵植物共有14科24种,其科、种数分别占到该生态系统所有植物的48.3%与26.1%。入侵植物白花三叶草与加拿大一枝黄花在春、秋两季均显著降低了河流滨岸带植物群落的物种多样性。此外,两种入侵植物也对当地河流滨岸及土壤特性造成了不同程度的影响,其中对土壤含水量、pH值的影响最为显著。该研究填补了平原河网地区河流滨岸带生态系统外来植物入侵研究的空白,有助于今后开展对该生态系统的评价、恢复及管理工作。

As a typical open system, riparian zone can be easily invaded by alien plants and result in severe consequences under the exposures of outside disturbance. To show how alien invasive plants impact riparian ecosystem, a study was conducted in Qingpu District, Shanghai in this research. The status of alien plants invasion was investigated, and the impacts on biodiversity and soil characteristics from two species： Trifolium repens and Solidago canadensis were analyzed. The result shows： a total of 24 different invasive alien plants from 14 families were found in this ecosystem. This constitutes about 48.3% and 26.1% of all flora families and species respectively. In particular, the appearances of the invasive alien plants, T. repens and S. canadensis decreased the species diversity significantly during spring and autumn. These two plants also altered the soil characteristics, with significant impacts observed in soil moisture content and pH value. This research fills the knowledge gap of how alien plants invasion affect riparian zone in plain river network area, and findings here can contribute to the evaluation, restoration and management work of riparian zone in future.