水位调控措施治理互花米草对大型底栖动物群落的影响

Effect of managed waterlogging to control Spartina alterniflora on macrobenthic communities

采用物理控制措施治理崇明东滩自然保护区外来入侵植物互花米草(Spartina alterniflora)的蔓延和扩散,对保护该地区的生物多样性具有重要的意义。研究跟踪了崇明东滩治理互花米草示范样地内水位调控措施对大型底栖动物群落的影响。结果显示,潮间带大型底栖动物的密度和生物量具有显著的季节性波动,实施持续水位调控措施样地中大型底栖动物的密度、生物量和丰富度指数均显著低于同时期对照样地。破堤排水后的恢复样地中,随着恢复时间延长,大型底栖动物密度、生物量和丰富度指数均有不同程度的恢复。应用DCA排序方法有助于进一步分析大型底栖动物群落与水位调控措施强度之间的相互关系。研究结果表明,水位调控措施会对盐沼植被中大型底栖动物的密度、生物量和多样性产生负面影响,但这种影响在治理互花米草水位调控措施结束后可逐渐自然恢复。

Physical measures to control the spreading of an invasive plant Spartina alterniflora are important and for biodiversity conservation at the Chongming Dongtan Nature Reserve. A field survey was carried out to trace the managed waterlogging on the macrobenthic communities at the demonstration site. The results showed that necessary impact of managed waterlogging treatments had caused significant decreases in the density, biomass and diversity of macrobenthic community. Moreover, the community structure of macrobenthos was different drastically with the control site. After 12 month waterlogging and breaking the dike, the density, biomass and diversity of macrobenthos could recover gradually as compared with the control site. The between the recovery site measure of managed waterl while such negative effects result of multivariate analysis DCA ordination revealed that differences in community structure and the control site reduced gradually. The results from this study indicated that the control ogging could have a negative impact on the macrobenthic community under saltmarsh vegetation, could be recovered by natural processes after ending the waterlogging treatment.