中文摘要：

为深入研究人工草地方法在治理青藏高原“黑土滩”的作用,从植物群落物种组成角度分析了三江源区退化的人工草地分别与“黑土滩”退化草地和未退化的天然草地之间的接近程度.结果表明：退化人工草地、“黑土滩”和天然草地中,平均物种数分别是29,32和35种.退化人工草地中禾本科重要值占群落总量的21％,“黑土滩”中杂类草重要值占群落总量的88.2％,天然草地中禾本科和莎草科的重要值占群落总量的37.4％.草地群落的Shannon-Wiener指数、Simpson优势集中性指数和Pielou均匀度指数都是天然草地＞“黑土滩”＞退化人工草地.Sorensen指数和Jaccard指数表明退化人工草地和“黑土滩”群落的相似性最大,“黑土滩”和天然草地的次之,退化人工和天然草地的相似性最小.退化人工草地中毒杂草比例较“黑土滩”中少10％左右.表明人工草地措施在一定程度上促进了“黑土滩”退化草地植物群落的恢复性演替.

英文摘要：

In order to further study the effect of artificial grassland on restoring the ＂heitutan＂,the species compositions of plant communities in degraded artificial grassland,＂heitutan＂ and natural grassland were analyzed.The results showed that the average species number of degraded artificial grassland,＂heitutan＂and natural grassland was 29,32 and 35,respectively.The important value of gramineae accounted for 21% of total community in the degraded artificial grassland,the important value of forbs accounted for 88.2% of total community in the ＂heitutan＂.The important value of gramineae and cyperaceae accounted for 37.4% of total community in the natural grassland.Shannon-Wiener indexes,Simpson dominant concentration indexes and Pielou evenness indexes of different grasslands were all ordered as natural grassland 〉＂heitutan＂〉degraded artificial grassland.Sorensen and Jaccard indexes showed that degraded artificial grassland and ＂heitutan＂ had the biggest community similarity,followed by ＂heitutan＂ and natural grassland,degraded artificial grassland and natural grassland had the smallest community similarity.The percentage of forbs in degraded artificial grassland was about 10% less than ＂heitutan＂.The conclusion was that artificial grassland was degraded after several years,but the artificial grassland promoted the restoration of degraded plant community in ＂heitutan＂ to a certain extent.