Department of Biology, Aarhus University, Ny Munkegade 116, 8000, Aarhus C, Denmark.
Department of Ecoscience, Aarhus University, C. F. Møllers Allé 8, 8000, Aarhus C, Denmark.
Oecologia. 2023 Apr;201(4):1039-1052. doi: 10.1007/s00442-023-05351-8. Epub 2023 Apr 5.
The exploration of factors and processes affecting biodiversity loss is central to nature management and wildlife conservation, but only recently has knowledge about the absence of species been recognized as a valuable asset to understand the current biodiversity crisis. In this paper, we explore the dark diversity (species that belong to a site-specific species pool but that are not locally present) of breeding birds in Denmark assessed through species co-occurrence patterns. We apply a nation-wide atlas survey of breeding birds (with a 5 × 5 km resolution), to investigate how landscape characteristics may influence avian diversity, and whether threatened and near threatened species are more likely to occur in dark diversity than least concern (LC) species. On average, the dark diversity constituted 41% of all species belonging to the site-specific species pools and threatened and near-threatened species had a higher probability of belonging to the dark diversity than least concern species. Habitat heterogeneity was negatively related to dark diversity and the proportional cover of intensive agriculture positively related, implying that homogeneous landscapes dominated by agricultural interests led to more absent avian species. Finally, we found significant effects of human disturbance and distance to the coast, indicating that more breeding bird species were missing when human disturbance was high and in near-coastal areas. Our study provides the first attempt to investigate dark diversity among birds and highlights how important landscape characteristics may shape breeding bird diversity and reveal areas of considerable species impoverishment.
探讨影响生物多样性丧失的因素和过程是自然管理和野生动物保护的核心，但直到最近，人们才认识到缺乏物种的知识是理解当前生物多样性危机的宝贵资产。本文通过物种共存模式探讨了丹麦繁殖鸟类的暗多样性（属于特定地点物种池但本地不存在的物种）。我们应用全国范围内繁殖鸟类的地图集调查（分辨率为 5×5 公里），研究景观特征如何影响鸟类多样性，以及受威胁和近危物种是否比最不关注（LC）物种更有可能存在于暗多样性中。平均而言，暗多样性构成了属于特定地点物种池的所有物种的 41%，受威胁和近危物种属于暗多样性的可能性高于最不关注物种。生境异质性与暗多样性呈负相关，集约农业的比例覆盖与暗多样性呈正相关，这意味着以农业利益为主导的同质景观导致更多的鸟类物种缺失。最后，我们发现人为干扰和距海岸距离的显著影响，表明在人为干扰高和近海岸地区，繁殖鸟类的物种缺失更多。本研究首次尝试调查鸟类中的暗多样性，并强调了重要的景观特征如何塑造繁殖鸟类多样性，并揭示了物种严重匮乏的地区。
