【作者】 贾晓妮；

【导师】 程积民；

【作者基本信息】 中国科学院研究生院（教育部水土保持与生态环境研究中心） ， 生态学， 2008， 硕士

【摘要】 草地是陆地生态系统的主要组成部分和重要的人类生存栖息地,占整个陆地生态系统的25.4%。草地生态系统的物质和能量循环对整个陆地生态系统乃至全球生物地球化学循环起着重要的作用,所以说草地资源的保护对人类生活具有重要的意义。封育作为一种主要的草地恢复措施,在实践中已经有了很多的应用,本文是以云雾山草原自然保护区本氏针茅草地群落为研究对象,对在25年封育过程中,群落数量特征(高度、盖度、多度、生物量、密度)、群落物种多样性、群落演替的变化过程,以及水分因子对群落生物量的影响。研究结果如下:1.封育措施的实施,对群落特征产生了显著的影响,除了群落多度有显著下降的趋势外,群落高度、盖度及生物量都是随封育措施的实施显著增加的趋势。但是由于封育时间的不同,产生效益的程度不同,由本研究的结果看出,封育8～10年为最佳效果。2.群落多样性的变化主要用3类指数来说明:多样性指数、丰富度指数以及均匀度指数。由于封育措施的实施,显著增加了各不同坡位的物种多样性指数和丰富度指数,总体上都是随着封育时间的增加由显著小于未封育群落→与未封育群落之间没有显著差异→显著大于未封育群落;但是均匀度指数则是表现为由于封育措施的实施,显著降低了各坡位的均匀度指数。随着封育时间的不同,3类指数表现为多元的变化趋势,各个指数的峰值也出现在不同的封育年份中,多样性指数的峰值出现在8～9 a,丰富度指数的峰值出现在第2 a、16 a、25 a,而均匀度指数的峰值出现在1～2 a。这整个复杂的变化也是一个上升→下降→上升相互循环的趋势,但是总体上认为封育8～10 a的时间群落达到最佳状态。3.通过分析降水量、储水量和耗水量与地上生物量之间的关系表明,无论是封育还是未封育群落的地上总生物量都与当年9月、去年9月及去年9～12月的降雨量极显著相关;封育草地的总生物量与4月份及10月份土壤1～5 m储水量都极相关,未封育草地群落的总生物量与3～4 m土壤的储水量关系极显著相关;封育和未封育群落的总生物量都与耗水量没有显著的相关关系,而只有分科中的某科与土壤耗水量的关系显著,封育群落中表现为蔷薇科,而在未封育群落中表现为豆科。4.云雾山本氏针茅草地群落的演替规律是:在自然状态下,本氏针茅草地群落→大针茅草地群落,这是在25 a的封育过程中表现出来的,并且在前16 a的封育时间里面,群落的演替一直朝着DCA排序轴的第一轴正方向发生变化,并且随着封育时间的增加,呈现明显的变化趋势。但是在封育16 a以后的时间里,群落的演替并没有随着封育时间的增加而呈现出一致的变化趋势,而是循环演替,并且这种演替的前提条件是以大针茅为优势种的草地群落。更多还原

【Abstract】 Grasslands are the main component of land ecosystems and the most important place to human being to live. Grasslands of various types cover approximately 25.4% of total land area of the world. The cycle of material and energy in grassland ecosystem plays an important role in total land ecosystem, even global biogeochemical cycling. Enclosure is one of importance manner to restore grassland, and have largely used in practical. The study was conducted on Stipa bungeana grassland Community in Yun Wu Mountain Nature Reserve. Based on the plot, the change of community characteristics (height, coverage, abundance, biomass, density) , community species diversity, community succession and relationship between water and community biomass in 25 years are analysis.The main research results were as follows:1. Many years enclosure changed the community characteristics,but the change was difference in every community characteristic. The community height, community coverage and community biomass in the enclosure sample are higher in non-enclosure, but the changed direction of community abundance was in reversed. Because of the different enclosure time, the effect of enclosure was different. In this research we can see that the best enclosure is 8～10 years.2. The diversity index,richness index and evenness index are three important index are used to explanation the change of community species diversity. Because the implementation of enclosure measure, the diversity index and richness index of Stipa bungeana community enclosure in every slope position are higher than non-enclosure, and the change dynamic as follow: along with the enclosure time increase from the enclosure<non-enclosure to no difference with enclosure and non-enclosure to the enclosure>non-enclosure. But the change of evenness index was difference, the evenness index in enclosure community are lower than non-enclosure community. The biggest value of every index was appearance at different time. The peak value of diversity index was appearance in 8～9 years, the richness index in the 2、16、25 years, the evenness index in 1～2 years. The whole complex change is a cycle of rise and drop, overall, the community diversity was good at enclosure 8～10 years.3. We analyzed the relationship between aboveground biomass and precipitation, soil moisture storage capacity, water consumption. Results indicated that there were significant correlations(p<0.05)between aboveground total biomass of enclosure and non-enclosure community and September,last year September, last September-December precipitation; the relationship between aboveground biomass of enclosure community and one-five meter soil moisture storage capacity of April and October is extremely significant correlations(p<0.01); there were no significant correlations between water consumption and total aboveground biomass of enclosure and non-enclosure community, but the biomass of some family of Rosaceae in enclosure community and ochrantha in non-enclosure community have significant correlation with water consumption4. The succession rule of Stipa bungeana grassland community in Yun Wu Mountain is: in nature station, In brief, the grassland community succession was changed with a trend over from Stipa bungeana community to Stipa grandis community in 25 years enclosure. In the enclosure pre-16 years, the community succession toward the right direction of first axis in ordination of DCA, at the same time, the community has happened significant change along with the enclosure time increase. But in the latter 9 years, the community has not the same change with the enclosure time increase, instead of cycle succession, and prerequisite of this succession is that Stipa grandis is dominant species in grassland community.更多还原