红松天然林胸径生长的空间异质性及其与地形的关系

Spatial heterogeneity of diameter at breast height growth for Korean pine natural forest and its relationships with terrain factors

【目的】探讨红松天然林胸径生长的空间异质性及其与地形因子的关系,为科学管理经营红松天然林提供借鉴。【方法】通过采用地统计学、方差分析、地理加权回归等方法,对白河林业局的红松天然林胸径生长的空间异质性及其与海拔、坡位、坡向和坡度等地形因子的关系进行了研究。【结果】研究区内红松天然林胸径生长变异系数为0.6,属于中等变异性,其空间变异特征最适合用指数模型来描述,且模型拟合度高;红松天然林胸径生长在0~4 230 m范围内存在强烈的空间自相关;运用普通线性回归(OLS)与地理加权回归(GWR)方法建立基于地形因子的红松天然林胸径生长模型,预测结果显示,GWR方法较OLS方法提高了预测精度。【结论】红松天然林胸径生长在一定范围内具有较强空间异质性,且会因地形因子的变化而产生差异,其中海拔、坡向对胸径的生长影响较大。

[ Objective ] The spatial heterogeneity of DBH growth for natural Korean pine forests and its relationship with terrain factors were discussed for providing a basis for scientific management. [ Method ] Geo-statistical, variance analysis, geographically weighted regression and other methods were used to study the spatial heterogeneity of DBH growth for natural Korean pine forest and its relationships with altitude, slope position, slope orientation and slope gradi- ent in Baihe Forestry Bureau. [ Result] The coefficient of variation for DBH growth in natural Korean pine forest was 0.6, which belonged to moderate variability in the study area. The exponential model with highly fitting degree was the most suitable way for describing spatial variation characteristics. The spatial autocorrelation of spatial distribution of DBH growth in natural Korean pine forest was significant in the range of 0-4 230 m. The method of OLS and GWR were cho- sen to establish the DBH growth model for natural Korean pine forest based on terrain factors. The results showed that the prediction accuracy was improved by the GWR method compared to OLS method. [ Conclusion] The spatial heterogeneity of DBH growth for natural Korean pine forest was significant and produced difference with the change of terrain factors. The change of altitude and slope orientation exerted greater influence on the DBH growth.