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采用空间点格局分析中的Ripley L和O-ring函数,以大兴安岭盘古林场森林资源二类调查数据为例,对比分析2种方法在森林景观类型的空间分布格局及其关联性研究中的差异.结果表明:2种方法获得的景观空间分布格局在整体趋势上反映一致,都是在中小尺度上呈聚集分布,之后随着尺度的增大主要表现为随机分布特征;景观类型间的关联性存在显著差异,其中,Ripley L函数结果表明,天然落叶松林、天然白桦林分别与针阔混交林在中小尺度上呈负相关,而在更大尺度上整体表现出无关联性或正关联性的趋势,其余景观类型间在所有研究尺度上呈显著负相关;O-ring函数结果则表明,4种森林景观类型两两之间均呈现出相似的关联性变化趋势,即在小尺度上均表现为负相关,在中等尺度上均呈现出不相关性,但在更大尺度上呈正相关趋势;对同一景观类型(或景观类型组),2种方法在不同尺度等级上的空间分布格局及其关联性的判别一致率存在较大差异,其一致性判别率在所有研究尺度上整体呈现出基本不变、先下降后增加和一直下降3种趋势.
Using the Ripley L and O-ring functions in spatial point pattern analysis and taking the second type of survey data of forest resources in Pangu Forest Farm of Daxinganling as an example, the differences between the two methods in the spatial distribution patterns and their correlations of forest landscape types were analyzed. The results show that the landscape spatial distribution pattern obtained by the two methods is consistent in the overall trend, all of them are aggregated at the small and medium scales, and then randomly distributed with the increase of the scale; the correlation between the landscape types exists The results of Ripley L function showed that the natural larch and natural birch forests were negatively correlated with the coniferous and broad-leaved mixed forests at the small and medium scales, while the larger ones showed no or no positive correlation , While the other landscape types showed significant negative correlations on all the research scales. The results of O-ring function showed that all the four forest landscape types showed a similar trend of correlation between each pair of landscapes, that is, Negative correlations showed no correlation at the middle scale but a positive correlation at a larger scale. For the same landscape type (or landscape type group), the two methods were in the Space on the same scale level distribution pattern and determine the relevance of the concordance rate there is a big difference in the rate of overall consistency determination showed essentially the same on all different scales increase and has been declining trend after the decline in the first three kinds.