Analysis on Diversity of the Wind-Breaking and Sand-Fixing Forest in Peripheral Regions of Oasis

摘要

The aim of this study was to characterize the diversity of artificial vegetation and provide evidence of reasonable distributional patterns for the artificial wind-breaking and sand-fixing forest in the periphery of oasis, in the lower reaches of the Tarim River, Xinjiang, China. The species diversity of artificial-natural plant community four years later was calculated by the measurable description of species richness index, Simpson index, and Shannon-Wiener diversity index, community evenness. The main results are as follows: (1) The artificial-natural communities are formed since several native species naturally occurred or invaded to the artificial communities in four years. (2) The species diversity is obviously increased in the artificial-natural communities. And there are all 26 species belonging to 12 families, 25 genera in the study communities, including 3 species of arbor, 9 species of shrub or semi-shrub, and 13 kinds of herbage, 1 vine species. (3) The variety range of Shannon-Wiener index (H') is 2.08-3.99 in 9 communities, and its trend is similar to that of richness changes. (4) Comm. Halogeton glomeratus+Karelinia caspica has the highest diversity and evenness indices while Comm. Calligonum caput-medusae+Populus euphratica is on the contrary. The results may provide the relevant theories for the further optimization species composition of the wind- breaking and sand-fixing forest and enhancement the stability of artificial plant community in the ecological fragile area.