【作者】 杨永川；

【导师】 由文辉； 达良俊；

【作者基本信息】 华东师范大学 ， 生态学， 2005， 博士

【摘要】 植被格局的空间差异和特定的地形构造密切相关。地形通过地貌过程,对植被产生直接作用,同时,通过形态的变化控制光、热、水和土壤养分等资源因子的空间再分配,对植被产生间接影响。因此,在同一气候区,地形是影响植被格局的最重要的因子之一。湿润的丘陵地区本身是主要被水侵蚀而形成的包含各种干扰频率的生境复合体,是一个从小流域角度来研究植被与地形的关系的理想单元。中亚热带地区是中国陆地生物多样性的关键地区之一,其东部地区以低山丘陵为主要地貌类型,这是与人类的生活关系最为密切的地区,也是人为影响最强的地区。其植被往往在人为干扰和生境的双重梯度上表现出很高的多样性和复杂性。本研究选择浙江东部低山丘陵地区具有典型代表意义的天童国家森林公园,引入起源并发展于日本温带地区的丘陵地多级地形分类体系,在地形识别的基础上,通过详细的植被及相应的环境因子,如土壤理化性质、林内光照和温度等的调查与分析,从地形-植被相关性着手,在小地形、微地形以及群落内部等不同尺度上研究其丰富的群落类型和物种多样性的形成与维持机制。主要结果如下: 1)此次研究在天童国家森林公园内共确认出7个微地形单元,顶坡(Crest slope,CS)、上部边坡(Upper sideslope,US)、谷头凹地(Head hollow,HH)、下部边坡(Lower sideslope,LS)、麓坡(Foot slope,FS)、泛滥性阶地(Flood terrace,FT)和谷床(Rive bed,RB)。这7个微地形单元可通过侵蚀前线(Erosion line)被归为上部坡面(Upper hillslope area,CS,US,HH)和下部坡面(Lower hillslope area,LS,FS,FT,RB)2个小地形单元,从而构成中尺度的低山丘陵地形单元。 2)土壤含水率上部坡面沿CS向HH递增,而后在下部坡面向FT递减。而土壤养分上部坡面,特别是CS和US优于下部坡面各微地形单元。林内光照强度下部坡面各微地形单元除RB外,均低于上部坡面。林内温度在沿山脊到沟谷包含3个微地形单元的样带上没有明显的差异。 3)依据各微地形单元的物种组成,可以将其划分为2组,即上部坡面和下部坡面,与通过侵蚀前线划分的结果一致。依据物种在这2个小尺度地形单元的分布更多还原

【Abstract】 The spatial differences in vegetation structure are related to particular configuration of landforms nearly. The landforms could influence vegetation directly though geomorphic process, such as slope failure, transportation sedimentation and erosion etc., on the other hand, they could create a gradient of light, water and nutrient available etc. though their relief and then influence vegetation indirectly. So landforms are assumed to be one of the most principle and decisive factors affecting the vegetation pattern within a climatic region. The humid hilly regions are the habitat complex containing various disturbance frequency eroded by water and they are a reasonable research unit for the study on the relationship between vegetation and topography.The mid-subtropical area is one of the key areas of biodiversity in China. In its eastern part, hills and lower mountains are the main geomorphic type. It’s the area nearly related to human life, so it’s also the area most affected by human activities. The vegetation developed there often show high diversity and complexity under the combined gradients of human disturbances and habitats. So we selected Tiantong National Park, a representative hilly and lower mountainous land area with well-protected vegetation in East Zhejiang, to study the form and maintenance of rich community types and species from the viewpoint of relations between vegetation and landforms.The multi-leveled classification of landform units established in temperate region in Japan was introduced and used as the survey of vegetation and the corresponding environmental factors, such as the physical and chemical characters of soil, the light and temperature within the stand etc. Then differentiation and maintenance of community patterns along the topographical gradients were analyzed based on the field survey data from different scales. Main results include:1) Seven micro-landform units were recognized in Tiantong National Park, namely CS(Crest slope), US(Upper sideslope), HH(Head hollow), LS(Lower sideslope), FS(Foot slope), FT(Flood terrace) and RB(River bed). There was a clear border line(Erosion line) dividing the seven micro-landform units into two parts, UHA(Upper hillslope area, CS, US, HH) and LHA(Lower hillslope area, LS, FS, FT, RB). These two detailed landform units then formed an intermediate-scale section,hilly and lower mountainous land area.2) The water content of soil increased from CS to HH in the UHA, and decreased to FT in the LHA, and the soil nutrient conditions in UHA, especially CS and US, were better than those in LHA. The light quantum within the stands in LHA is lower than that in UHA except for RB, and the temperature hadn’t obvious difference among four plots along a transect with a relative elevational difference of 140m.3) The seven micro-landform units were divided into two parts based on the similarity of species composition, namely UHA and LHA, and that was coincident with the result divided by erosion line. And three species group were obtained based on the distribution patterns among the UHA and LHA. Group A mostly or strictly confined to UHA, group B confined to LHA and group C associated statistically with neither part. Evergreen species of Fagaceae, Theaceae, Symplocaceae and Aquifoliaceae were the main components of the vegetation developed in UHA, however, deciduous species of Juglandaceae, Ulmaceae, Anacardiaceae and evergreen species of Lauraceae were the main components of vegetation developed in LHA. The diversity among the micro-landform units in UHA was higher than that in LHA, especially species richness and Shannon-Wiener index. And these two indexes of ground vegetation were higher than that of woody layer among the seven micro-landform units.4) Though the densities were higher, the vertical structure of the forest stands on the micro-landform units in UHA was more complex than that in LHA. The existence of emergent layer and individuals composed by species of Juglandaceae, Ulmaceae and Anacardiaceae was the remarkable feature of the forest stands in LHA.5) F更多还原