鄱阳湖湿地植物群落沿高程梯度变化特征研究

Research on variation of wetland plant communities along elevation gradient around Poyang Lake

鄱阳湖湿地植物群落地理分布特征的研究对鄱阳湖的生态保护具有重要意义。基于野外植物群落的样方调查,结合数字高程模型,分析了鄱阳湖湿地植物在不同高程范围内的分布格局和变化特征。结果表明:鄱阳湖湿地植物以禾本科、莎草科、蓼科和菊科等植物最为常见,地上生物量随高程呈上升趋势;物种丰富度与高程呈非线性正相关关系,Shannon指数、Simpson指数在高程上均呈下降-上升-下降趋势;12.5～13.5 m高程范围内,生境差异较小,Jaccard指数较大,在12～12.5 m和14.5～15 m高程范围内,生境差异较大,属于湿生植物到中生、旱生(或沙生)植物的过渡地带,15 m高程以上植物生长环境趋于稳定。

The research on geographic distribution of wetland plant communities around Poyang Lake has an important signifi- cance to ecological protection of Poyang Lake. Based on field investigation of plant communities and in the combination of digital elevation model, the distribution condition and variation characteristics of wetland plant along elevation gradient around Poyang Lake are analyzed. The analysis results show that plants of Gramineae, Cyperaceae, Polygonacea, Compositae are the most com- mon ones in the wetland of Poyang Lake and the above - ground biomass increases with elevation ; the species richness has a non - linear positive correlation with elevation and indexes of Shannon and Simpson has a decrease - increase - decrease variation trend; in the elevation range of 12.5 -13.5 m, the difference of habitat is smaller and Jaccard index is larger, in the elevation ranges of 12 - 12.5m and 14.5 - 15 m, the difference of habitat is larger and they belong to the transition belts of Haptophytes to Mesophytes and Xerophytes （or Psammophyte） ; above 15 m, the plant growth environment tends to be stable.