Schmuki C, Vorburger C, Runciman D, Maceachern S, Sunnucks P
Department of Genetics, La Trobe University, Victoria, Australia.
Mol Ecol. 2006 May;15(6):1481-92. doi: 10.1111/j.1365-294X.2006.02849.x.
Anthropogenic activities continue to cause massive fragmentation and reduction of forest area worldwide. With fragmentation and reduction of habitat recognized as the greatest threats to biodiversity, the implementation of improved, informed and conservation-based forestry practices is essential, and requires a greater understanding of the responses of different organisms to forest fragmentation. While genetic techniques can add invaluable insights to fragmentation studies they have rarely been employed, particularly for multiple species. In the present study, we combined genetic information, obtained from allozyme loci and anonymous single copy nuclear DNA markers, with ecological data to investigate the impacts of forest fragmentation on two log-dwelling beetles with different life histories, in an 'islands of bush in a sea of pine' model, at Tumut in New South Wales, Australia. Both the relatively mobile (i.e. has high dispersal ability and/or broad habitat range) Adelium calosomoides and the less mobile Apasis puncticeps showed reduced mobility and gene flow in fragmented compared to continuous forest: there was significantly greater isolation by distance and stronger local structure revealed by spatial autocorrelation in fragmented forest. Analysis of patch and species characteristics revealed that genetic and demographic structure may be influenced by log degradation class for both species, and number of potential dispersal barriers, distance from continuous forest and desiccation intolerance/moisture preference for Ap. puncticeps. Thus the pine plantation matrix poses a barrier or filter for gene flow and mobility in both beetle species.
人为活动持续导致全球森林面积大规模破碎化和减少。由于栖息地破碎化和减少被认为是对生物多样性的最大威胁，实施改进的、基于科学知识且注重保护的林业实践至关重要，这需要更深入了解不同生物对森林破碎化的反应。虽然遗传技术可为破碎化研究提供宝贵见解，但它们很少被应用，尤其是针对多个物种。在本研究中，我们将从等位酶基因座和匿名单拷贝核DNA标记获得的遗传信息与生态数据相结合，在澳大利亚新南威尔士州图穆特的“松海之中的丛林岛屿”模型中，研究森林破碎化对两种具有不同生活史的树栖甲虫的影响。与连续森林相比，相对移动性较强的（即具有高扩散能力和/或广泛栖息地范围）卡洛索莫德氏阿德利姆甲虫和移动性较弱的点状阿帕西斯甲虫在破碎化森林中的移动性和基因流均有所降低：在破碎化森林中，距离隔离显著更大，空间自相关揭示的局部结构更强。斑块和物种特征分析表明，两种物种的遗传和种群结构可能受原木退化等级影响，对于点状阿帕西斯甲虫，还受潜在扩散障碍数量、与连续森林的距离以及干燥不耐受性/湿度偏好的影响。因此，松树人工林基质对两种甲虫的基因流和移动性构成了障碍或过滤器。
