白洋淀流域河岸带草本植物群落分布特征与土壤环境因子的关系

Relationship between herbaceous community distribution and soil environmental factors in the riparian zone of the Baiyangdian River Basin

河岸带植被是河岸带生态系统的重要组成部分,在河岸带功能发挥中具有重要的作用,而草本植物作为河岸带植被的主要类型之一,具有对环境变化和人类活动响应更加敏感等特点,成为河岸带植被研究的热点之一.选取白洋淀4条典型入淀河流(孝义河、瀑河、府河和白沟引河)河岸带草本植物群落作为研究对象,采用典型样地法,系统调查了入淀河流河岸带草本植物种类,运用Shannon-Wiener多样性指数(H′)、Pielou均匀度指数(J)和Patrick丰富度指数(R)等方法分析草本植物群落的组成和物种多样性特征,并采用冗余分析方法(RDA)探讨4条入淀河流河岸带草本植物群落物种多样性、群落分布格局及其与土壤环境因子之间的关系.(1)白洋淀入淀河流河岸带共调查了草本植物27科66属83种,植物组成多为杂草或伴人植物,主要有禾本科(Poaceae)、菊科(Compositae)和藜科(Chenopodiaceae)等,河岸带植被受到人为干扰的影响较大.(2)孝义河、白沟引河和府河的H′、J和R表现较好,而瀑河最差.(3)研究区河岸带草本植物群落的植被盖度、物种多样性与土壤有机质和含水率呈正相关关系,而与pH、总氮和总磷呈负相关关系.因此,在河岸带核心地区减少人类活动的干扰,增加湿度,更有利于植被的恢复和生物多样性的稳定.(图7参36)

Riparian zone vegetation is an important part of the riparian ecosystem and plays an important role in the riparian zone functioning. Herbs, which are one of the main types of riparian vegetation, are extremely sensitive to environmental changes and human activities and have become a hot spot of riparian vegetation research. In this study, the herbaceous communities of four representative rivers(Xiaoyi, Baohe, Fuhe, and Baigouyin River) entering Baiyangdian Lake in China were researched. The herbaceous species in their riparian zones were systematically investigated using the sample plot method. The Shannon-Wiener diversity(H’), Pielou evenness(J), and Patrick richness(R) indices were estimated to examine the species composition and diversity of the herb communities,following which redundancy analysis(RDA) was conducted. The relationship between species diversity, distribution patterns of herbaceous plant communities, and soil environmental factors in the riparian zone of the four rivers is discussed.(1) Eighty-three species of herbaceous plants belonging to 66 genera and 27 families in the riparian zone entering Baiyangdian Lake. Most herbaceous plants, including Poaceae, Compositae, and Chenopodiaceae,were weeds or associated plants. Riparian vegetation was greatly affected by human disturbance.(2) All the three estimated indices of the Xiaoyi, Baigouyin, and Fuhe rivers were better than those of the Baohe River.(3) The vegetation coverage and species diversity of riparian herbaceous communities were positively correlated with soil organic matter and water content but negatively correlated with pH, total nitrogen, and total phosphorus.Therefore, these communities are conducive to the restoration of vegetation and the stability of biodiversity in the riparian core area to reduce the disturbance of human activities and increase humidity.