地形因子对暖温带森林群落物种丰富度-地上生物量关系的影响

地形因子是森林群落物种丰富度与生产力的重要影响因素,可以修正物种丰富度-生产力两者之间的关系。为了厘清地形因子对物种丰富度-生产力关系的修正效应,以东灵山暖温带天然次生林为研究对象,基于20 hm2样地DEM地图,提取海拔、坡度、坡向、凹凸度等地形因子,用GLM模型探讨了地形因子对群落丰富度与地上生物量的影响。结果表明,群落地上生物量与物种丰富度分别受不同地形因子的影响,群落地上生物量受Ea、El2、El3、Co34个因子的显著影响（P〈0.05）,而物种丰富度则受Sl、El、El2、El34个因子的显著作用（P〈0.05）,两者受海拔相关因子的影响最大,分别解释了两者3.99%和11.09%的变异。地形因子修正了物种丰富度-地上生物量之间的单峰曲线关系,使其朝着单调与直线化趋势变化。以后在探讨森林群落物种丰富度-生产力关系时,地形因子的修正作用应该受到重视。

Effect of topographic factors on the relationship between species richness and aboveground biomass in a warm temperate forest

The terrain factor is an important influencing factor of forest species richness and productivity, and it can correct the relationship between species richness and productivity. In order to clarify the effects of topographical factors on species richness - productivity relationship amendments, we studied topographic factors such as elevation, slope, aspect, convex effected on community richness and aboveground biomass with the GLM model in the 20 hm2 Donglingshan forest dynamic plot in a warm temperate deciduous broad-leaved secondary forest. The result showed that the terrain factors influencing aboveground biomass are different from those which affected species richness. Aboveground biomass was significantly influenced by four factors： Ea, E12, E13 and Co3（p〈0.05）. Species richness was also influenced by four factors including S1, El, El2 and El3（p〈0.05）. The altitude-related factors were the biggest influence factors, respectively explaining 3.99% and 11.09% of the variation of aboveground biomass and species richness. The terrain factor amended the unimodal relationship between species richness and aboveground biomass, and the relationship was adjusted to the monotonous, straight line trend. In exploring the forest species richness and productivity relations in the future, amendments role of topographic factors should be taken seriously.