We studied the impacts of selective logging on the spatial structure of tree species composition in the tropical rain forest of Sabah, Malaysia. We established 50 20-m radius plots (0.12 ha in area) across primary to highly degraded forests in each of two logging concessions with distances in between any two plots ranging from 0.2 to 40 km. In addition, we established one 100 × 200-m plot in each of primary, reduced-impact logged, and conventionally logged forest in other two logging concessions, and each plot was divided into 40 × 30-m quadrats (0.12 ha in area) for the further analysis of the spatial structure at the scale of less than 200 m. A decline of species-compositional similarity with increasing in-between distance was found in primary and moderately logged forest at both larger and smaller than 0.2-km scale. Such a spatial structure could not be detected in heavily logged forests at both scales. The heavily logged forests were rather characterized by mosaics of remnant stands and regenerating patches of pioneer species, leading to a high spatial variance of species composition without the distance-dependent spatial structure. Accordingly, high-impact conventional logging damages the distance-dependent spatial structure of species composition in canopy tree communities by creating random vegetation patches, while reduced-impact logging can maintain the spatial structure.

我们研究了选择性伐木对马来西亚沙巴热带雨林树木物种组成的空间结构的影响。我们在两个采伐特许权的每一个中，在原始森林至高度退化的森林中建立了50个20米半径的样地（面积为0.12公顷），任何两个样地之间的距离为0.2至40 km。此外，我们在其他两个伐木特许权的每个主要，减灾伐木和常规伐木林中分别建立了一个100×200-m的样地，并将每个样地划分为40×30-m的四方类（面积为0.12公顷）用于进一步分析小于200 m规模的空间结构。在大于和小于0.2 km的范围内，原始和中度采伐的森林中物种组成相似性随中间距离的增加而下降。在这两个尺度上，在茂密的森林中都无法检测到这种空间结构。砍伐茂密的森林的特征是残留的林木镶嵌和先驱物种的再生斑块，导致物种组成的高度空间变异，而没有距离相关的空间结构。因此，高影响力的常规伐木通过产生随机的植被斑块而破坏了冠层树群落中物种组成的距离相关的空间结构，而减少影响的伐木可以维持空间结构。导致物种组成的高度空间变异，而没有距离相关的空间结构。因此，高影响力的常规伐木通过产生随机的植被斑块而破坏了冠层树群落中物种组成的距离相关的空间结构，而减少影响的伐木可以维持空间结构。导致物种组成的高度空间变异，而没有距离相关的空间结构。因此，高影响力的常规伐木通过产生随机的植被斑块而破坏了冠层树群落中物种组成的距离相关的空间结构，而减少影响的伐木可以维持空间结构。