【作者】 张艳丽；

【导师】 贾志斌；

【作者基本信息】 内蒙古大学 ， 草业科学， 2008， 硕士

【摘要】 皇甫川流域是黄河中游右岸的一级支流,发源于鄂尔多斯高原与黄土高原的过渡地带,在陕西省境内流入黄河。皇甫川全长120km,流域面积3240 km~2,流域主体部分位于内蒙古准格尔旗境内。本文以准格尔旗贺家湾水土保持试验站恢复治理区和未治理区植被为研究对象,从植物群落的分类排序、群落优势种的生态位宽度和生态位重叠、物种多样性及种间关系等方面深入探讨了该地区退化天然草地植物恢复演替进程中的群落类型、结构、物种组成及分布格局,分析了物种多样性与群落类型、生境、群落结构之间的关系,以及主要优势种的种间关系。应用TWINSPAN分类,把98个样方划分成9个群丛和2个群聚,DCCA排序划分为7个群落类型。DCCA排序结果表明,第一轴反映了植被盖度、土壤养分、放牧强度、坡度和坡向的变化规律,同时也反映了群落演替时间的长短。第二轴反映了海拔梯度和坡位的变化规律。不同的植物群落在排序图上也有各自的分布范围。物种的DCCA排序可用36个种代替,划分成A、B、C和D四个生态种组。从A→D,随着恢复演替的进展,一二年生植物逐渐减少,多年生根茎型禾草和丛生禾草植物逐渐增加,并趋于稳定。通过丰富度指数、物种多样性指数和均匀度指数,结合TWINSPAN,DCCA排序,研究了该流域天然草地恢复演替进程中的物种多样性及其变化机制。不同演替阶段物种丰富度、均匀性和多样性存在差异。环境因子对丰富度指数、物种多样性指数和均匀度指数的变化有一定程度的影响。在该流域植被的优势种生态位的研究方面,用Levins,Shannon-Wiener生态位宽度公式和Levins生态位特定重叠指数公式测定恢复演替不同阶段群落中优势种生态位宽度和生态位重叠,并分析各种群生态位的生态学意义。一二年生草本植物狗尾草、猪毛菜和黄蒿的生态位宽度值在演替过程中逐渐减小,而本氏针茅、短花针茅和羊草的生态位随群落恢复的进行生态位宽度逐渐增大。表明本氏针茅、短花针茅等丛生禾草和羊草等根茎禾草在恢复中后期阶段具有较强的资源利用能力。在该流域优势种的种间关系的研究方面,运用x~2检验方法对群落优势种进行总体相关性和种对间的联结性检验,利用共同出现百分率Jacccard指数和Ochiai指数测定种对间的关联度,应用Pearson相关系数和Spearman秩相关系数刻画种对间的数量变化关系。该流域优势种群间的相关性多显示为负相关,表明优势种在多种因素干扰的情况下,群落处于动态之中,大多群落尚未达到稳定状态。更多还原

【Abstract】 Huangfuchuan is the first tributary of the middle reaches of the Yellow River, originated from the transitional zone between the Ordos Plateau and the Loess Plateau , inflowed the Yellow River in Shanxi Province. The total length of Huangfuchuan is 120 km and drainage area is 3240 km~2, the main part of Basin in the Zhungeer Region. This paper selected the part as study area. The succession of plant communities were studied by using quantitative methods, including classification and ordination, species diversity, interspecific association and correlation, and niche breadth and overlap. The types, structure, ecological relationships between species and communities in the succession procedure were analyzed in details.98 samples were divided into 9associations and 2Cluster by TWINSPAN, 7 community types by DCCA, each of them has their own characteristics. The result of DCCA ordination showed that different plant communities and their distributing area varied along the environmental gradients in the ordination graph. The first axis of DCCA soil denoted the soil nutrients, slope, vegetation cover, gradient and the second axis of DCCA denoted change of altitude and aspect. The result of DCCA 36 species can be used to divided into four ecological groups. From A→D, with the of the restoration succession, gradually reduce the annual and biennial herbs, perennial herbs, small shrubs and small semi-bush plants gradually increaseBy using of the richness, diversity and evenness indices, combined with TWINSPAN and DCCA techniques, species diversity and diversification mechanism were studied. Different stages of succession have a certain degree differences of species richness, diversity evenness indices. Environmental factors have a certain degree of impact on these indices change.The main dominant species of niche breadths and overlaps were measured using a series of indices proposed by Levins, Shannon-Wiener, analysed niche group of ecological significance .The results indicated the niche breadth of annual herbs eg. Setaria viridis,Salsola collina, Artemisia scoparias gradually decreased in the process succession, the niche breadth of Stipa bungeana, Stipa breviflora, Leymus chinensis gradually increased. The results indicated Stipa bungeana, Stipa breviflora, Leymus chinensis have strong capacity utilization of resources in the late stages of recovery.x~2 test, Jacccard indices and Ochiai indices were used to analyze the interspecific association of 19 dominant species of community. Pearson’s correlation coefficient and Spearman’s rank correlation coefficient were also applied to calculate correlations between species. In this region, negative correlations between groups indicate that the community Is in a dynamic state because of the disturb to the dominant species by many factors, most communities have not reached a steady state.更多还原