森林生产力与立地条件的相关性分析——以宁明县的马尾松和桉树森林生产力为例

以广西主要树种马尾松和桉树在宁明县的森林生产力为例，采用生物量连续函数法求算林地生物量，据此推算样地生产力，利用高精度的1：10000数字高程模型（DEM）求算研究区域的坡向、坡度、海拔，运用TPI指数求取坡位和地貌类型，利用P值检验法分析研究不同树种的森林生产力与立地条件的相关性。结果表明：立地因子与马尾松、桉树生产力相关性较高，但相关性在树种间存在差异性；海拔、坡位和土壤种类这三个因子均对马尾松与按树的生产力有制约作用；地貌类型和土层厚度因子对马尾松影响明显，而坡向和成土母岩因子则对桉树影响明显；坡度对两树种生长的影响均较小。由此可见，森林生产力与立地条件的相关程度取决于森林树种，不同树种的相关性结果不一致。研究结果为正确地构建森林生产力的预测估算模型和合理地进行营造林树种布局规划提供理论依据。

The Correlation between Forest Productivity and Site Condition -- A Case Study of Forest Productivity of Pinus massoniana and Eucalypt in Ningming County

Taking the forest productivity of Pinus massoniana and Eucalypt in Ningming county of Guangxi for example,based on the biomass of forests calculated by the method of biomass continuous function to reckon the productivity of sample plots,using high accuracy Digital Elevation Model(DEM)(1:10 000) to calculate slope aspect,slope degree and elevation of research areas and the Topographic Position Index(TPI)to estimate slope position and landform type,the correlation between different forest species’ productivity and site condition was studied by using P(Probability)value inspection.The results showed that correlation between site condition and productivity of Pinus massoniana and Eucalypt was remarkable,which was various among different forest species.Site conditions of elevation,slope position and soil type played restricted role in productivity of Pinus massoniana and Eucalypt.The effect of landform type and thickness of soil on Pinus massoniana was obvious while slope aspect and soil mother rock were correlative to Eucalypt.The effect of slope degree on Pinus massoniana and Eucalypt was less.So the correlation between forest productivity and site condition depended on forest species.This research would provide theory basis for establishing calculation model of forest productivity correctly and planning the layout plan of planting species reasonably.