青土湖水面形成过程对荒漠植物多样性的影响

目的]分析青土湖输水过程对荒漠植物种多样性影响,为青土湖输水后的生态功能分析提供参考。方法]通过4a的定位观测数据计算,分析青土湖岸植物种的多样性以及植物种的时间与空间变化及其与地下水位关系。结果]距水面200m范围的植物种数量减少,其中距水面0m的植物种减少最多,100m处物种变化最少。Shannon-Weiner,Pielou指数和Simpson指数变化趋势相似,丰富度和多样性减小,均匀度和优势度增大;其中植物种优势度变化相对较大,且空间变化速率大于时间变化率,但Cody指数的时间变化率大于空间变化速率。结论]青土湖输水促使植物种及其多样性以水源为中心呈带状变化,形成特征植物圈,且随地下水位上升变化程度增大。

Effects of Qingtu Lake Water Area Formation on Diversity of Plants in Desert Region

Objective] The objective of this study is to investigate the influence of water delivery process on diversity of the plants in Qingtu Lake in order to provide basis for functional analysis in this region. Methods] After a four year locating observation, biodiversity index was applied to analyze plant diversity in Qingtu Lake shores. The relationships between plant diversity variation and underground water level were also investigated. Results] The number of plant species reduced within 200 m range from the water surface, and the maximum reduction occurred at the surface of water while the minimum reduction occurred at 100 m. Shannon-Weiner, Pielou index and Simpson index showed a similar trend, richness and Shannon-Weiner decreased, while Pielou index and Simpson index increased. Simpson index changed greatly, and the spatial variation was greater than the temporal variation. In contrast, the temporal variation of the Cody index was greater than the spatial variation. Conclusion] Importing water to Qingtu Lake had prompted the spatial distribution of plant species. The water source is centre for the belt distribution of the plant species, and the change increase with the rise of the underground water level.