围栏封育对草原植被及多样性的影响  

Effect of Fencing on Vegetation and Diversity of Steppe in the Middle Section of Northern Slope of the Tianshan Mountains,China

作　　者：孙宗玖[1] 安沙舟[1] 马金昌[1] 

机构地区：[1]新疆农业大学草业工程学院新疆草地资源与生态自治区重点实验室,新疆乌鲁木齐830052

出　　处：《干旱区研究》2007年第5期669-674,共6页Arid Zone Research

基　　金：新疆草地资源与生态重点实验室项目(XJDX0209-2004-02);新疆农业大学教研项目资助

摘　　要：通过对乌鲁木齐地区典型草原围栏内外植被特征、多样性指数、土壤种子库及地下生物量的调查研究,结果表明：2年围栏后,草原植物群落的盖度、产量有大幅度提高,显著高于围栏外,且优势种表现更加明显;围栏内外物种丰富度指数S、优势度指数D和Shannon-Wiener指数H′、均匀度指数Jsw差异不显著;围栏内0～5 cm和10～15 cm土层中的地下生物量明显高于围栏外,但地下总生物量差异不显著,且主要分布在0～15 cm的土层中;围栏后的土壤种子总数及分层种子数明显高于围栏外,且种子主要集中在0～5 cm的土层中。In this study, the effects of fencing steppes on the vegetation characteristics, plant diversity index, soil seed bank and underground biomass in the study area are investigated. The study area （43°32′N, 87°12′E, 1 780 m a. s. l. ）, a typical steppe in Gangou Township of Urumqi County, 60 km from Urumqi City, is located in the middle section of northern slope of the Tianshan Mountains, where the annual precipitation varies in a range of 380 ～ 420 mm, the vegetation is dominated by grasses, and the dominant species are Festuca ovina, Stipa capillata, Ajania fastigiata, Carex liparocarpos, Saussurea sp. and commonly accompanied by Astragalus membranaceus, Kochia prostrata, etc. In the study, the plant height, vegetation coverage and density and grass yield in the plots of 1 m × 1 m are measured and analyzed. The study results show that the coverage and yield of the steppe vegetation communities are greatly increased after the steppes are fenced for 2 years comparing with that of steppes without fencing, especially that of dominant species; the differences of species richness index （S）, dominance indexes （D and H′） and uniformity index （Jsw） between the fenced and un-fenced steppes are not so significant. The underground biomass in soil layers of 0 ～5 cm and 10 ～ 15 cm in depth in the fenced steppes is significantly higher than that in the un-fenced ones, but the difference of total underground biomass of vegetation communities between the fenced and un-fenced steppes is not so significant, and the underground biomass is mainly distributed in soil layer of 0 ～ 15 cm in depth. Amount of total seeds and stratified seeds in soil seed bank is obviously increased after fencing the steppes, and the seeds are mainly distributed in soil layer of 0 ～ 5 cm in depth. 　

关 键 词：围栏 植被 多样性 地下生物量 土壤种子库 天山北坡 乌鲁木齐 

分 类 号：S812[农业科学—草业科学]