白洋淀湿地水生植物群落物种多样性及对环境因子的响应

Species Diversity of Aquatic Plant Communities and its Response with Environmental Factors in Baiyangdian Wetland

探讨湿地水生植物群落物种多样性特征以及主要环境驱动因子,能够为湿地水生植物群落保护与恢复提供参考。本研究基于白洋淀湿地30个2 m×2 m水生植物群落样方,利用重要值衡量群落中优势种,并划分不同群落,探讨不同水生植物群落物种多样性及其与环境因子之间的关系。结果表明:出现在样方内的水生植物共18种,隶属12科13属;根据物种优势度可将群落类型划分为芦苇(Phragmites australis)群落、香蒲(Typha orientalis)群落、莲(Nelumbo nucifera)群落、篦齿眼子菜(Potamogeton pectinatus)群落;4种水生植物群落物种组成差异显著,Shannon-Wiener指数和Margalef丰富度指数芦苇群落最高,莲群落的Simpson指数、Pielou均匀度指数和Berger-Parker优势度指数最高、篦齿眼子菜群落的物种多样性指数均较低;白洋淀湿地水生植物群落物种多样性受多重环境因子的影响,4种水生植物群落物种多样性指数对环境因子的响应各异,其中,水体硝态氮、水体铵态氮、底泥速效磷、底泥碱解氮等营养盐元素对白洋淀水生植物群落物种多样性有显著影响,水体铅和水体砷与物种多样性显著负相关。白洋淀湿地水生植物群落物种多样性与生境条件有着密切的联系,探明影响群落物种多样性的限制性环境因子,可有效促进白洋淀水生植物群落物种多样性。

Exploring the species diversity and main environment driving factors can provide reference for the protection and restoration of aquatic plant community.In this study,based on the data of 30 aquatic plant community plots(with a size of 2 m×2 m)of Baiyangdian wetland,and dominant species were used to classify the different communities.We used the diversity indices and Pearson correlation analysis to explore the species diversity of different aquatic plant communities and relationship between species diversity and environment factors.The results showed that there were 18 species belonging to 12 families and 13genera in plots.According to the species dominance,the aquatic plant communities could be categorized into four types,including Phragmites australis community,Typha orientalis community,Nelumbo nuc ifera community and Potamogeton pectinatus community.There were signifcant differences in species composition for four aquatic plant communities,the Shannon-Wiener diversity index and Margalef richness index were highest in Phragmites australis community,the Simpson diversity index,Pielou evenness index and Berger-Parker dominance index were the highest in Nelumbo nucifera community,and the species diversity indices of Potamogeton pectinatus community was lower.The species diversity of aquatic plant communities were affected by multiple environmental factors in Baiyangdian wetland.The species diversity indices had different responses to environmental factors.Among them,nutrient contents such as water nitrate nitrogen,water ammonia nitrogen,soil available phosphorous,soil alkaline-hydrolyzable nitrogen had significant impact on the species diversity,and water Pb and As was significantly negatively correlated with species diversity of aquatic plant community.The results suggested that the species diversity of aquatic plant community were closely related to the environmental factors.Exploring the constraints environmental factors affecting the species diversity could effectively promote the species diversity of aquatic plant community in Baiyangdian wetland.