内蒙古乌拉盖草原湿地中下游植被退化演替趋势分析

Analysis of Vegetation Degeneration Succession Trend in Middle and Lower Reaches of Wulagai Wetland of Inner Mongolia

针对内蒙古锡林郭勒盟东乌旗乌拉盖草原湿地植被退化问题,采用植被生态调查方法进行生态损伤评估和植被演替趋势分析。调查结果表明:在乌拉盖河截流5年内,乌拉盖湿地中下游植被退化迅速,原生植被的建群种和优势种基本消失,群落高度和盖度迅速降低,原生植被群落重要值显著降低,次生植被群落重要值增加;植物种的数量大量减少,植物多样性严重降低;一年生草本植物数量和比例明显高于多年生草本植物,部分荒漠化严重地区还出现超旱生植物小果白刺(Nitraria sibirica Pall.);乌拉盖草原湿地已经从草原湿地植被演替为碱蓬盐化草甸植被和盐漠化裸地。

The method of vegetation investigation was applied to evaluate ecological damage and analyze vegetation succession trends in middle and lower reaches of Wulagai Wetland for the problem of vegetation degradation of Wulagai Wetland in Inner Mongolia.The result showed that vegetation in middle and lower reaches of Wulagai Wetland was degenerated rapidly after Wulagai river was closured for 5 years.Original and dominant species almost disappeared,community height,coverage and original community important value decreased,but secondary community important value increased.Plant diversity decreased seriously,annual plants was more than perennial plants,super-xeric plant Nitraria sibirica Pall.appeared in part of serious desertification areas.Wulagai Wetland had been in succession from steppe wetland to Suaeda salinity meadow vegetation and salt desertification bare land.