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机构地区:[1]北京林业大学水土保持学院中国防治荒漠化培训中心,北京100083
出 处:《生态环境》2007年第5期1481-1484,共4页Ecology and Environmnet
基 金:国家自然科学基金项目(30771764);国家林业局项目(660550)
摘 要:封育措施是一种主要的草场恢复和重建的措施。通过对半干旱沙地老封育、新封育和对照区的比较分析,量化了不同封育措施下植被变化。对3种封育措施群落组成和生物多样性的分析结果表明,封育改变了群落的组成成分并增加了生物多样性,同时对群落植物的生活型、饲用价值分析计算结果则显示,老封育的群落植物逐渐向多年生发展,放牧价值开始降低,而对照区则明显处于一种非平衡的稳定状态。从3种措施植被的盖度、高度、生物量和饲用价值来看,老封育区均低于新封育区和对照区,表明长期封育不利于促进并提高草场的放牧利用价值。Exclusion has been applied as a main measure for revegetation. This paper, by comparing the results of old exclusion, new exclusion and comparative exclusion, quantified the vegetation variations under three different exclusion measures. The analysis rcsults for community species component and plant diversity showed that exclusion did change the species component and increase plant diversity remarkably, while the indieateor life-form structure, palatability analysis indicated that community for old exclusion is becoming perennity and unpalatability, whereas community for comparative exclusion is under stable non-equilibrium condition, in the view of vegetation coverage, mean height, biomass, palatability of plant composition, community for old exclusion has lower than new, comparative exclusion which proves partly that long-term exclusion can not increase grazing values for semi-arid rangeland.
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