Department of Integrative Ecology, Estación Biológica de Doñana EBD (CSIC), Seville, Spain.
Institute of Agriculture and Environmental Sciences, Estonian University of Life Sciences, Tartu, Estonia.
Conserv Biol. 2023 Dec;37(6):e14131. doi: 10.1111/cobi.14131. Epub 2023 Aug 14.
Global-change drivers are increasing the rates of species extinction worldwide, posing a serious threat to ecosystem functioning. Preserving the functional diversity of species is currently a priority to mitigate abrupt biodiversity loss in the coming decades. Therefore, understanding what factors better predict functional diversity loss in bird assemblages at a global scale and how existing protected areas cover the most vulnerable regions is of key importance for conservation. We examined the environmental factors associated with the risk of functional diversity loss under 3 scenarios of bird species extinction based on species distribution range size, generation length, and International Union for the Conservation of Nature conservation status. Then, we identified regions that deserve special conservation focus. We also assessed how efficiently extant terrestrial protected areas preserve particularly vulnerable bird assemblages based on predicted scenarios of extinction risk. The vulnerability of bird functional diversity increased as net primary productivity, land-use diversity, mean annual temperature, and elevation decreased. Low values for these environmental factors were associated with a higher risk of functional diversity loss worldwide through two mechanisms: one independent of species richness that affects assemblages with low levels of niche packing and high functional dissimilarity among species, and the other that affects assemblages with low species richness and high rates of extinction. Existing protected areas ineffectively safeguarded regions with a high risk of losing functional diversity in the next decades. The global predictors and the underlying mechanisms of functional vulnerability in bird assemblages we identified can inform strategies aimed at preserving bird-driven ecological functions worldwide.
全球变化的驱动因素正在增加全球物种灭绝的速度，对生态系统功能构成严重威胁。保护物种的功能多样性是缓解未来几十年生物多样性突然丧失的当务之急。因此，了解哪些因素能更好地预测鸟类群落功能多样性在全球范围内的丧失，以及现有的保护区如何覆盖最脆弱的地区，对保护具有关键意义。我们根据物种分布范围大小、世代长度和国际自然保护联盟保护状况，研究了与鸟类物种灭绝 3 种情景下的功能多样性丧失风险相关的环境因素。然后，我们确定了需要特别关注的地区。我们还评估了现存的陆地保护区根据预测的灭绝风险情景，保护特别脆弱的鸟类群落的效率。随着净初级生产力、土地利用多样性、年平均温度和海拔的降低，鸟类功能多样性的脆弱性增加。这些环境因素的低值与全球范围内功能多样性丧失的高风险有关，其机制有两种：一种是独立于物种丰富度的，影响那些生态位包容量低且物种间功能差异大的群落；另一种则影响那些物种丰富度低且灭绝速度快的群落。现有的保护区没有有效地保护未来几十年内功能多样性高风险地区。我们确定的鸟类群落功能脆弱性的全球预测因子和潜在机制，可以为保护全球鸟类驱动的生态功能的策略提供信息。
