安西荒漠鼠类群落结构与环境因子的无偏对应分析

A DETRENDED CORRESPONDENCE ANALYSIS OF COMMUNITY STRUCTURE OF DESERT RODENT AND ENVIRONMENTAL FACTORS IN ANXI

本文通过对安西荒漠鼠类群落结构与环境因子的无偏对应分析，得出决定鼠类群落结构的环境主导因子因季节不同而有所不同：春季是地下水位、海拔高度、平均降水量和平均气温；夏季是植被覆盖度、植物平均高度、土壤含水率和土壤坚实度；秋季是土壤含水率。综合春、夏、秋三季资料，植被覆盖度、土壤含水率和土壤坚实度是决定鼠类群落结构的环境主导因子。其中水是决定荒漠地区鼠类群落结构的最重要因子。

This study was carried out in Anxi desert,Gansu province from March to Octoberin 1990. the different type of plant community as sample plots were elected. Nine desertrodent communities were investigated in order to reveal the interrelations between thecommunity structure of desertrodents and the environmental factors, and found out thedeterminants of community structure. A kind of method of detrended correspondenceanalysis(DCA)was used by means of computer. In spring ,the locations of 9 communities on the second ordinate axis(informationwas 37.3%)of DCA was positive correlation with the ground water level , altitude andmean precipitation(r=0.08, p<0. 01; r=0. 81, p< 01 respectively),and negativecorrelation with the mean temperature(r=-0. 83, p<0.01). In summer, the locations of 9 communities on the second ordinate axis (informationwas 36.9%)of DCA was positive correlation with the vegetation coverage, plant height,soil moisture content and soil hard+degree(r=0. 86, p<0.01; r=0. 6, p<0. 05; r=0. 75,p<0. 01;r=0. 82, p<0. 01 respectively).In autumn,the locations of 6 communities on the first ordinate axis (information was 59.8%)of DCA was significantly negative correlation with the soil moisture content(r=-O.86,p<O.01).In general , the locations of 9 communities on the first ordinate axis(information was 60.3%)of DCA was significantly negative correlation with the vegetation coverage, soilmoisture content and soil hard-degree(r=-0. 89, p<0. 01; r=-0. 63, p<0. 05; r=-0. 68, p<0. 05 respectively). The vegetation coverage, soil moisture content and hard-degree were the determinants of community structure of desert rodents in Anxi, further-more, water was the most important determinant.