丹江口库区湿地植被的数量分类和排序

采用双向指示种分析法(TW INSPAN)和除趋势对应分析法(DCA)对丹江口库区的湿地植被进行了数量分类和排序。TW INSPAN把30个样地划分为14个群丛,论述了各群丛的群落学特征。样地的DCA排序结果反映了植物群落类型与环境因子之间的关系,表明土壤类型和生境的水分条件变化是决定丹江口库区湿地植被分布的主导因子。目前的丹江口水库滩涂植被主要由以狗牙根(Cynodon dactylon)、长刺酸模(Rum ex maritimus)、通泉草(Mazus gracilis)和稗(Echinochloa crusgalli)等为优势种的偏旱生群落类型构成。

Quantitative Classification and Ordination of Wetland Vegetations in Danjiangkou Reservoir Region

Danjiangkou Reservoir is the water supplying area of the Middle-Route of South-to-North Water Transfers Project.To serve that purpose,the existing Danjiangkou Dam will be elevated to the level of 176.6 m(above sea level) from 162 m,and the normal pool level will be 170 m instead of the present 157 m.Thus,analysis for the composition and distribution of existing vegetation in Danjiangkou Reservoir Region will provide data for wetland management and water environment maintenance of the future.The present paper detected the distribution patterns and species composition of the wetland vegetations using TWINSPAN and DCA in the Danjiangkou Reservoir Region.TWINSPAN classification divided the vegetation into 14 associations,and their community characteristics were described.DCA ordination of samples revealed that soil type and humidity were the main factors influencing the structure and distribution of wetland community.The current floodplain vegetation in Danjiangkou Reservoir was dominated by Cy-nodon dactylon,Rumex maritimus,Mazus gracili and Echinochloa crusgalli.