Magrach Ainhoa, Laurance William F, Larrinaga Asier R, Santamaria Luis
Center for Tropical Environmental and Sustainability Science (TESS) and School of Marine and Tropical Biology, James Cook University, Cairns, QLD 4878, Australia.
Conserv Biol. 2014 Oct;28(5):1342-8. doi: 10.1111/cobi.12304. Epub 2014 Apr 11.
Forest fragmentation dramatically alters species persistence and distribution and affects many ecological interactions among species. Recent studies suggest that mutualisms, such as pollination and seed dispersal, are more sensitive to the negative effects of forest fragmentation than antagonisms, such as predation or herbivory. We applied meta-analytical techniques to evaluate this hypothesis and quantified the relative contributions of different components of the fragmentation process (decreases in fragment size, edge effects, increased isolation, and habitat degradation) to the overall effect. The effects of fragmentation on mutualisms were primarily driven by habitat degradation, edge effects, and fragment isolation, and, as predicted, they were consistently more negative on mutualisms than on antagonisms. For the most studied interaction type, seed dispersal, only certain components of fragmentation had significant (edge effects) or marginally significant (fragment size) effects. Seed size modulated the effect of fragmentation: species with large seeds showed stronger negative impacts of fragmentation via reduced dispersal rates. Our results reveal that different components of the habitat fragmentation process have varying impacts on key mutualisms. We also conclude that antagonistic interactions have been understudied in fragmented landscapes, most of the research has concentrated on particular types of mutualistic interactions such as seed dispersal, and that available studies of interspecific interactions have a strong geographical bias (arising mostly from studies carried out in Brazil, Chile, and the United States).
森林破碎化极大地改变了物种的存续和分布，并影响了物种间许多生态相互作用。最近的研究表明，诸如传粉和种子传播等互利共生关系比诸如捕食或食草等对抗关系对森林破碎化的负面影响更为敏感。我们应用荟萃分析技术来评估这一假设，并量化了破碎化过程中不同组成部分（斑块面积减小、边缘效应、隔离增加和栖息地退化）对总体影响的相对贡献。破碎化对互利共生关系的影响主要由栖息地退化、边缘效应和斑块隔离驱动，并且正如预测的那样，其对互利共生关系的负面影响始终比对抗关系更为严重。对于研究最多的相互作用类型——种子传播，只有破碎化的某些组成部分具有显著影响（边缘效应）或边缘显著影响（斑块面积）。种子大小调节了破碎化的影响：种子较大的物种通过降低传播速率表现出更强的破碎化负面影响。我们的研究结果表明，栖息地破碎化过程的不同组成部分对关键的互利共生关系具有不同影响。我们还得出结论，在破碎化景观中，对抗性相互作用的研究较少，大多数研究集中在特定类型的互利共生相互作用上，如种子传播，并且现有的种间相互作用研究存在很强的地理偏差（主要源于在巴西、智利和美国开展的研究）。
