敦煌西湖盐化草甸芦苇群落特征及多样性沿水分梯度的分布格局

对敦煌西湖盐化草甸芦苇植物群落特征及多样性沿土壤水分梯度的分布进行了监测和研究.结果表明,试验区内主要植物以旱生和超旱生灌木、半灌木及草本植物为主.优势种为苏枸杞、疏叶骆驼刺、芦苇等,伴生植物有赖草、圆囊苔草、猪毛菜等,群落垂直结构明显,大体分为3层.通过对3条样线上生物多样性随水分梯度变化规律的分析,表明随着土壤水分的增加,丰富度指数dMe和均匀度指数E总体表现出先升高后降低的单峰趋势,优势度指数C总体呈现出先降低后升高的单谷趋势；Simpson多样性指数总体呈现先升高后降低再升高最后降低的双峰形式；Shannon-Wiener多样性指数和Simpson多样性指数表现出基本一致的变化趋势.

Dunhuang West Lake Salt Meadow Reed Plant Community Structure and Diversity Distribution Pattern Along Altitudinal Gradient

The community structure and diversity distribution pattern of salt meadow reed plant along soilmoisture gradient were studied in Dunhuang West Lake.The results showed that the test area was dominatedby xeric and highly xeric shrubs,subshrubs and herbaceous plants.The dominant species were Lycium ruthenicum,Alhagi Sparsifolia,Phragmites communis,and the companion plants were Leymus secalinus,Carex orbicularis,Salsola collina.The community structure could be divided vertically into three layers.The analysis of biodiversity on three transects showed that with the increase of soil moisture,richness indexand evenness index of dMe,Eincreased first and then decreased,showing an unimodal trend.In contrast,dominance index Coverall presented a single valley trend as it decreased first and then increased.Simpson diversity index showed a double-peak form and Shannon-Wiener diversity index and Simpson diversity indexremained consistent.