荒漠植物群落特征及其与气候因子的对应分析

2002-2008年,采用样方法对内蒙古典型荒漠区禁牧样地的植物群落进行了调查。以7年的调查结果和数据分析了荒漠植物群落的季节和年度特征,并利用除趋势对应分析(DCA)和典范对应分析(CCA)对植物群落特征与气候因子的相关性进行了排序分析。结果表明:灌木和草本植物的高度、盖度、密度和生物量的季节特征均为夏季和秋季间差异均不显著(P>0.05),而秋季显著高于春季(P<0.05)。灌木植物与草本植物群落特征的年动态具有差异,草本植物群落特征的年间波动大于灌木植物。DCA排序表明荒漠植物群落结构的季节性和年度间差异不明显。CCA排序表明草本植物特征因子与气候因子的相关性大于灌木植物。草本密度与年降水量的相关性较大,草本高度与年均温度的相关性较大,草本生物量与年降水量、年均温度的相关性均较大。

The characteristics of desert plant community and the corresponding analysis on climatic factors

From 2002 to 2008,a study was conducted to investigate plant community using quadrat method in prohibited-grazing area in Alxa desert.The seasonal and annual dynamic of desert plant community,and the relationship between plant community and climatic factors were analyzed using detrended correspondence analysis(DCA) and canonical correspondence analysis(CCA).The results showed that the height,cover,density and biomass of shrubs and herbs were no significant differences between summer and autumn(P > 0.05),while the plant community of autumn was significantly higher than in spring(P>0.05).There was difference in the plant community dynamics between shrubs and herbaceous,and herbaceous community was more volatile than shrub among years.The DCA analysis showed that community structure of desert plant was not significant seasonal and annual characteristics.The results of CCA demonstrated that herbs characteristic has a strong relation with climate factors than shrub.The herbaceous density had a greater relevance to the annual precipitation,the herbaceous height has a greater relevance to the annual average temperature,and the herbaceous biomass has a strong relation with the annual average temperature and precipitation.