“黑土滩”退化草地、高寒湿地及其交错区植物群落结构多样性

Diversity of plant community structure in "Black Soil" type degraded grassland and alpine wetland and their intersectional area

采用样方调查方法研究了青藏高原江河源区"黑土滩"退化草地、高寒湿地及其二者交错区的植物群落结构及其多样性。结果表明,交错区植物群落多样性最高,"黑土滩"退化草地植物群落多样性明显高于高寒湿地植物群落多样性。高寒湿地植物群落中以莎草科植物占优势,"黑土滩"退化草地则以毒杂草占绝对优势,交错区可食性杂草类群较多。从3种植物类型区物种构成变化看,尽管3者互相毗邻,但是"黑土滩"可能是其他高寒植被类型退化演替而形成,不能证明"黑土滩"与其临近的高寒湿地存在群落发生学关系。以毒杂草构成为主的"黑土滩"次生植被则对其周边高寒湿地具有明显的侵入性和生态胁迫,因此必须加强对江河源区"黑土滩"退化草地的治理。

The structure of plant community and diversity in ＂Black Soil＂type degraded grassland, alpine wetland and their intersectional Area was investigated in headwaters of Yellow River and Yangtze River on Tibetan Plateau. The results showed that the diversity of plant communities was the highest in the intersectional area （dominated by forbs）. The diversity of plant communities in ＂Black Soil＂type degraded grassland （dominated by the poisonous weeds） was significantly higher than that in alpine wetland （dominated by sedge）. From changes in species composition of the three areas ,it could be concluded that ＂Black Soil＂type degraded grassland might be from the succession other types of alpine vegetation although three communities were adjacent. And it could not be proved that ＂Black Soil＂ type degraded grassland related to alpine wetland. The plant community of ＂Black Soil＂type degraded grassland significantly invade and threaten the adjacent alpine wetland. Therefore , it is necessary to strengthen the management of the ＂Black Soil＂ type degraded grassland.