荒漠植物多样性及优势种群空间格局对环境响应分析——以古尔班通古特沙漠为例

Response of Plant Diversity in Desert and Dominant Population Spatial Pattern to the Environment——A Case Study of Gurbantunggut Desert

【目的】对植物多样性及优势种群空间格局在不同环境下的响应进行分析。【方法】根据带状样地调查数据,计算研究区离沙漠边缘不同距离、沙丘不同坡向植物群落α及β多样性指数,确定调查区植物群落优势种群及空间格局分布特征。【结果】(1)从沙漠边缘向腹地,植物α多样性指数(丰富度、Simpson、Shannon-Wineer、Pielou指数)均呈减少趋势,β多样性(Whittaker)指数则呈增加趋势;(2)植物多样性随坡度不同(西坡、东坡、丘间平地),由东坡、西坡到丘间平地,α多样性依次增加;由丘间平地、西坡到东坡Whittaker指数依次增加。(3)研究区优势植物种群为尖喙牛儿苗(Erodium hoefftianum)、角果藜(Ceratocarpus arenarius)、早熟猪毛菜(Salsola praecox)、荒漠庭芥(Alyssum desertorum)、早熟禾(Poa annua)、虫实(Corispermum lehmannianum)和白茎绢蒿(Seriphidium terrae-albae)且均呈聚集分布。【结论】水分条件是影响植物多样性分布及种群空间分布格局的主要因素。

【Objective】The present study was set to analyze species diversity and spatial pattern of dominant population under different invironments.【Method】The dominant population of plant communities and distribiction characters in spatial pattern were determined based on the data obtained from the study area.【Result】The results showed that（1）The α-plant species diversity showed decreasing trend;On the contrary,the β-diversity（Whittaker index）indices of these plant demonstrates an increasing trend.（2）Among the flat land、eastern and western slopes in the sand dune,α-plant diversity are increase,andβ-plant diversity show an increase trend among the flat land、western and eastern slopes.（3）Seven kinds of dominant population were distributed such as Erodium hoefftianum Population,C.arenarius Population,S.praecox Population,Alyssum desertorum Population,Poa annua Population,Corispermum lehmannianum,Seriphidium terrae.【Conclusion】Therefore,the water level was the determining factors for species diversity and distribution pattern of dominance population in the south of Gurbantunggut Desert.The conclusions can be referred in recognizing ecological adaptation and regular distribution in the study area.