宁夏盐池县植被恢复过程中的植物多样性研究

Plant Diversity in the Process of Vegetation Restoration in Yanchi County of Ningxia Hui Nationality Autonomous Region

通过聚类方法分析了盐池县天然草地、撂荒地、人工封育区和湿地4种样地的植被组成和群落特征，同时应用Shannon--Wiener指数、Simpson指数、群落均匀度指数和丰富度指数对植物多样性进行了研究分析，以了解植被恢复的状况。结果表明，四儿滩保护区湿地由于水分充足，其植物多样性明显高于其它样地，柳杨堡人工封育区的多样性高于天然草地及撂荒地，另外，降水量对植被恢复影响明显，由于降水量减少，2008年的植被特征值和多样性指数均比2006年和2007年有所减小，其中，2008年总的植被盖度相比减少50％～60％，无量殿天然草地和四儿滩保护区湿地的生物量都减少约50％，撂荒地减少60％，而柳杨堡人工封育区相比减少了70％，2008年4种类型样地的多样性指数均有小幅度的减小，而丰富度指数有明显的降低，封育区丰富度指数比2007年减少了约46％，四儿滩湿地比2006年减少12％，比2007年减少22％，另外，四儿滩湿地的均匀度指数受影响较大，2006年为0．905，2007年为0．836，而2008年降低到0．467。

To characterize the plants diversity under various protections in the process of vegetation restoration, the plant composition and community characteristic of grassland, abandoned land, artificial closure area, and natural wetland in Yanchi County were analyzed by means of clustering analysis as well as Shannon--Wiener index, Simpson index, evenness index, and richness index. Results revealed that the wet- land in Siertan Nature Reserve had the most biomass and the plant diversity of wetland in Liuyangpu artificial closure area was greater than natural grassland and abandoned land. The vegetation feature and plant diversi- ty in 2008 were less than those in 2006 and 2007 for less rainfall and the coverage in 2008 decreased by 50~ ~60 0~. The biomass in Wuliangdian natural grassland and Siertan wetland decreased by 50%; in abandoned land, about 60%; and in Liuyangpu artificial closure area, about 70%. In 2008, the diversity index of the four land types decreased slightly and the richness index decreased significantly. Compared with 2007, the richness index of artificial closure area on Siertan wetland decreased by 46% and 22%, respectively. Otherwise, the evenness index of Siertan wetland was seriously affected. It was 0. 905 in 2006, while it decreased to 0. 836 in 2007and 0. 467 in 2008.