PDF(Pubmed)
Abstract：
Forest transformation has major impacts on biodiversity and ecosystem functioning. Identifying the influence of forest habitat structure and composition on avian functional communities is important for conserving and managing forest systems. This study investigated the effect of forest structure and composition characteristics on bird species community structure, habitat use and functional diversity in 14 Mistbelt Forest patches of the Midlands of KwaZulu-Natal in South Africa. We surveyed bird communities using point counts. We quantified bird functional diversity for each forest patch using three diversity indices: functional richness, functional evenness and functional divergence. We further assessed species-specific responses by focussing on three avian forest specialists, orange ground-thrush Geokichla gurneyi, forest canary Crithagra scotops and Cape parrot Poicephalus robustus. We found that bird community and forest-specialist species responses to forest structure and tree species diversity differed. Also, forest structural complexity, canopy cover and tree species richness were the main forest characteristics better at explaining microhabitat influence on bird functional diversity. Forest patches with relatively high structural complexity and tree species richness had higher functional richness. Different structural characteristics influenced habitat use by the three forest specialists. Tree species diversity influenced C. scotops and G. gurneyi positively, while P. robustus responded negatively to forest patches with high tree species richness. Our study showed that site-scale forest structure and composition characteristics are important for bird species richness and functional richness. Forest patches with high tree species diversity and structural complexity should be maintained to conserve forest specialists, bird species richness and functional richness.
摘要：
森林改造对生物多样性和生态系统功能产生重大影响。确定森林栖息地结构和组成对鸟类功能群落的影响对于保护和管理森林系统很重要。本研究调查了森林结构和组成特征对鸟类群落结构的影响。南非夸祖鲁-纳塔尔省中部地区14个生态系统森林斑块的栖息地利用和功能多样性。我们使用点计数调查了鸟类群落。我们使用三个多样性指数量化了每个森林斑块的鸟类功能多样性：功能丰富度，功能均匀性和功能发散性。我们通过关注三名鸟类森林专家，进一步评估了特定物种的反应，橙色地面鹅口疮Geokichlagurneyi，森林金丝雀苏格兰和海角鹦鹉Poicephalusrobustus。我们发现鸟类群落和森林专家物种对森林结构和树种多样性的反应不同。此外，森林结构的复杂性，冠层覆盖和树种丰富度是主要的森林特征，可以更好地解释微生境对鸟类功能多样性的影响。具有相对较高的结构复杂性和树种丰富度的森林斑块具有较高的功能丰富度。不同的结构特征影响了三位森林专家的栖息地利用。树种多样性对C.scotops和G.gurneyi产生了积极影响，而P.robustus对树种丰富度较高的森林斑块反应消极。我们的研究表明，场地尺度的森林结构和组成特征对鸟类物种丰富度和功能丰富度很重要。应保持树种多样性和结构复杂性高的森林斑块，以保护森林专家，鸟类物种丰富度和功能丰富度。
