中文摘要：

为了查明乌鲁木齐南部山区地生地衣群落分布格局,作者选取了24个样点（20m×20m）,设置了240个50cm×50cm样方,调查地生地衣的种类及盖度,分析其分布格局及其与环境因子的关系。结果表明,乌鲁木齐南部山区共有地生地衣17种,隶属于2目5科10属。聚类分析和DCA排序将该地区的地生地衣分为4个主要样点组,分别是：（1）喇叭石蕊（Cladonia pyxidata）＋腐石蕊（C.cariosa）＋喇叭粉石蕊（C.chlorophaea）群落,共有7种,总盖度为19.7%;（2）双孢散盘衣（Solorina bispora）＋腐石蕊＋粗皮石蕊（C.scabriuscula）群落,共有11种,总盖度为21.1%;（3）雪岛衣（Cetraria nivalis）＋喇叭石蕊群落,共有3种,总盖度最小为8.05%;（4）地卷（Peltigera rufescens）＋多指地卷（P.polydactyla）群落,共有7种,总盖度为23.83%。CCA排序结果显示,该地区地生地衣的分布与海拔高度、郁闭度、人为干扰和湿度有关,其中影响最大的因素是海拔高度,其次为郁闭度和干扰。不同海拔高度的植物群落郁闭度不同,到达地面的光照强度也有差异,所以不同海拔的地生地衣种类及多样性有显著性差异。

英文摘要：

Forest floor lichens are sensitive to variations in habitat conditions.To understand the distributional patterns of forest floor lichen communities and how habitat factors relate to dominant lichen species composition and diversity,we sampled 240 plots（50 cm×50 cm） in the mountainous area of southern Urumqi,Xinjiang,China.We detected 17 species in total,belonging to 10 genera and 5 families.Cluster analysis and detrended correspondence analysis（DCA） showed that plots clustered into four groups：（1） a Cladonia pyxidata ＋ Cladonia cariosa ＋ Cladonia chlorophaea community,including seven species with a total coverage of 19.7%;（2） a Solorina bispora ＋ Cladonia cariosa ＋ Cladonia scabriuscula community,including 11 species with a total coverage of 21.1%;（3） a Cetraria nivalis ＋ Cladonia pyxidata community,including three species with a total coverage of 8.1%;and（4） a Peltigera rufescens ＋ P.polydactyla community,including seven species with the total coverage of 23.83%.Canonical correspondence analysis（CCA） indicated that the species composition and diversity of floor lichens were most strongly influenced by altitude,then forest canopy density and humidity;the distribution patterns of lichen communities were apparently influenced by human disturbance.Variation in lichen communities among different elevations was related to light availability at ground level.