中文摘要：

采用空间序列替代时间序列的方法,对科尔沁沙地不同演替阶段3个冷蒿群落的物种组成和物种多样性进行研究.结果表明：处于3个演替阶段的冷蒿群落为杠柳-冷蒿群落、杠柳-冷蒿＋差巴嘎蒿群落及冷蒿-糙隐子草群落.3个冷蒿群落均以菊科、禾本科和藜科植物占优势.随着群落的演替,群落植物种数和科数逐渐减小,禾本科植物的种数逐渐减小,但菊科和禾本科植物种数所占比例逐渐增大.3个冷蒿群落中物种多样性顺序为：杠柳-冷蒿＋差巴嘎蒿群落〉杠柳-冷蒿群落〉冷蒿-糙隐子草群落.3个冷蒿群落间的物种组成差异不大,群落间物种相似度较高.3个群落中冷蒿的盖度最大,其盖度随着群落的演替逐渐增大.

英文摘要：

Taking space as a substitute for time,this paper studied the species composition and species diversity of Artemisia frigid community at three succession stages in Horqin Sandy Land.The three succession stages were Periploca sepium-A.frigida community,Periploca sepium-A.frigida＋A.halodendron community,and A.frigida-Cleistogenes squarrosa community,all dominated by the plants of Compositae,Chenopodiaceae and Gramineae.The species number and family number in the communities and the species number of Gramineae decreased with succession,while the percentages of Compositae and Gramineae species increased.The species diversity of the communities was in the order of P.sepium-A.frigida＋A.halodendron P.sepium-A.frigida A.frigida-C.squarrosa.No obvious difference was observed in the species composition among the three communities.In the three communities,A.frigida had the highest coverage,and the coverage increased with succession.