【作者】 郭华；

【导师】 王孝安；

【作者基本信息】 陕西师范大学 ， 植物学， 2004， 硕士

【摘要】 太白红杉主要分布在秦岭主峰太白山地区，多为纯林生长，在海拔2500～3500m之间延山脊两侧呈带状分布。在秦岭其它地区，如洋县长青自然保护区、西安长安区光头山和柞水县牛背梁自然保护区等地亦有零散分布。本文选取太白山和长安光头山为研究对象，通过对两地太白红杉种群分布格局特征的研究，阐明了太白红杉种群在秦岭地区不同生境的分布格局特征及其动态变化过程，并从影响太白红杉种群格局特征的生物(种间、种内关系)和自然环境两个角度，分析了影响太白红杉种群分布格局的关键因子，探讨了太白红杉种群分布格局形成的原因。 野外调查应用相邻格子样方法采集数据，用计盒维数和信息维数研究了太白红杉种群空间格局的分形特征，结果显示，在太白山地区太白红杉种群格局具统计自相似性，有较高的计盒维数(1.8087)和信息维数(1.7931)，表明其对空间占据程度较高；在光头山地区太白红杉种群格局亦具统计自相似性，有较高的计盒维数(1.8247)，但信息维数(1.2428)较低，表明其对空间占据程度较高，但结构较为简单。运用分布系数法、Moore的φ检验、Morisita格局指数法、Hopkins和Skellam的A值法等方法进行检验，发现不同样地太白红杉种群均呈聚集分布，且不同年龄组的太白红杉在太白山地区亦呈聚集分布。应用Greig-Smith方法对太白红杉的格局规模进行了研究，发现太白山的太白红杉种群在128m~2和512m~2处聚集，不同年龄组在不同规模尺度都表现聚集：光头山的太白红杉种群在50m~2和400m~2处聚集。用多种聚集强度指标检测其聚集强度，并用区组均差法绘制格局强度分析图，发现太白红杉种群格局强度随尺度变化程度较大，个体分布不均匀，随着年龄的增大，其聚集强度呈下降趋势。太白红杉种群的空间分布格局特征可能是其对严酷生境长期适应的结果。 对不同尺度下的太白红杉种群密度和格局强度的关系进行多项式回归分析。结果表明太白红杉种群的种内竞争强度，可在较小尺度上解释其种群格局的成因。应用2×2列联表的Fisher精确检验，分别研究了太白山和光头山太白红杉群落中的种间关系。另外，用Pearson积矩相关系数检验了种对间的数量变化关系。研究结果表明，太白红杉群落种间关系较为简单，但草本层物种间连接相对较为复杂，灌木层次之。乔木层中，太白红杉和巴山冷杉呈显著的负协变效应。太白红杉群落种间关系与太白红杉种群格局的形成关系不大，不宜用来解释其种群格局的成因。 用主成分分析研究了太白山、光头山样地以及总体生境的环境因子对太白红杉种群格局的影响，结果显示太白红杉种群格局特征受环境因子的影响。在较大尺度上，其分布格局受各自分布地区的水、热、光、土壤以及地形条件的影响，他们决定着太白红杉种群的大尺度分布格局特征以及分布区域，主要影响因子有海拔高度、坡度、坡向等。但在较小尺度下，具体到不同分布地区内部，小生境的差异性，如林窗、斑块化的资源分布等，则影响着太白红杉种群在较小尺度上的分布状态，使得各个分布区域之间产生不同的分布格局特征(如差异明显的格局聚集尺度和强度)，并使得各地的太白红杉个体生长状况产生差异，产生不同的空间占据能力。更多还原

【Abstract】 Larix chinensis populations distributed in a wider area, but mainly distributed in Mt.Taibai, which was the the highest peak in Qinling mountain range. They arrayed like strips both sides of the ridges between altitude 2500 and 3500 meters. In other areas of Qinling Mountain, such as Changqing National Nature Reserve in Yang County, Mt.Guangtou in Chang’an borough in Xi’an City and Niubeiliang National Nature Reserve in Zhashui County, L. chinensis populations distributed sporadic. In this article, Mt.Taibai and Mt.Guangtou were selected to be samples. The spatial pattern characters of L.chinensis populations in the two sample areas were studied. The results illustrated the spatial pattern characters and the dynamic changing progress of L.chinensis populations in different habitat in Qinling Mountain. Then, the biology factors (including innerspecis and interspecis relationship) and the environment factors, which as the key factors affected the spatial pattern characters of L.chinensis populations, were analysed and the reasons leading to the the spatial pattern characters of L.chinensis populations were discussed.Field data were sampled by the method of contiguous grid quadrate when studing the spatial pattern characters of L.chinensis populations. The fractal characters of L.chinensis populations in Mt.Taibai and Mt.Guangtou were studied by boxing-counting dimension and information dimension. The results of Mt.Taibai, higher boxing-counting dimension (1.8087) and information dimension (1.7931), reflected that there was a higher spatial occupational degree in L. chinensis populations. The results of Mt.Guangtou, higher boxing-counting dimension (1.8247) and lower information dimension (1.2428), reflected that there was a higher spatial occupational degree in L.chinensis populations, but the instruction was comparative simple. The spatial pattern types of L.chinensis populations in two sample areas were studied by the following methods: dispersal index, Moore’s^) test, Morisita’s pattern index, Hopkins and Skellams’ A index, Taylor method and Iwao method. The results showed that L.chinensis populations clumped totally and, in Mt.Taibai sample areas, clumped in the three different age stages (0-25, 25-50 and over 50 years) too. Then, the pattern scalewas studied by Greig-Smiths’ mean variance. The figure of pattern scale showed that L.chinensis populations clumped in 128 m and 512 m in Mt.Taibai and the different age groups clumped in different scales. In Mt.Guangtou, L.chinensis populations clumped in 50 m2 and 400 m2. Finally, the pattern intensities were researched by Kershaw’s PI index and some other indexes. The results indicated tha the distribution of L. chinensis was not even and the pattern intensities were decreasing with the age increasing and tended to reduce with the area increasing. The spatial pattern characters of L.chinensis populations maybe were the response to the environmental factors.The relations of the population density and the pattern intensity of L.chinensis in different scales were analysed by multinomial regress. The results showed that the current spatial pattern of L. chinensis populations could be explained by the innerspecis competitive intensity in smaller scale. The species in communities of. L.chinensis both in Mt.Taibai and Mt.Guangtou, and their interspecific relationship were studied by using Fisher’ s exact test for a 2X2 contingency table. In addition, Pearson’s correlation coefficient was applied to test for correlation between species. The results showed that the interspecific relationships of L. chinensis communities were simpler, but more abundant in herb layer and less in shrub layer. In arbor layer, L.chinensis and Abies fargesii obviously showed their significant negative covariation. Drawing a conclusion, there was no obvious pertinence between the interspecis relationship and the population spatial pattern of L.chinensis. So, the interspecis relationship would be inapplicable to explain how forming the current spatial pattern of L.chinensis populations.The更多还原