Division of Forest, Nature and Landscape, Department of Earth and Environmental Sciences, KU Leuven, Leuven, Belgium.
Alliance Bioversity International - CIAT, Lima, Peru.
Glob Chang Biol. 2020 Jun;26(6):3552-3568. doi: 10.1111/gcb.15028. Epub 2020 Mar 26.
Understanding the vulnerability of tree species to anthropogenic threats is important for the efficient planning of restoration and conservation efforts. We quantified and compared the effects of future climate change and four current threats (fire, habitat conversion, overgrazing and overexploitation) on the 50 most common tree species of the tropical dry forests of northwestern Peru and southern Ecuador. We used an ensemble modelling approach to predict species distribution ranges, employed freely accessible spatial datasets to map threat exposures, and developed a trait-based scoring approach to estimate species-specific sensitivities, using differentiated trait weights in accordance with their expected importance in determining species sensitivities to specific threats. Species-specific vulnerability maps were constructed from the product of the exposure maps and the sensitivity estimates. We found that all 50 species face considerable threats, with an average of 46% of species' distribution ranges displaying high or very high vulnerability to at least one of the five threats. Our results suggest that current levels of habitat conversion, overexploitation and overgrazing pose larger threats to most of the studied species than climate change. We present a spatially explicit planning strategy for species-specific restoration and conservation actions, proposing management interventions to focus on (a) in situ conservation of tree populations and seed collection for tree planting activities in areas with low vulnerability to climate change and current threats; (b) ex situ conservation or translocation of populations in areas with high climate change vulnerability; and (c) active planting or assisted regeneration in areas under high current threat vulnerability but low climate change vulnerability, provided that interventions are in place to lower threat pressure. We provide an online, user-friendly tool to visualize both the vulnerability maps and the maps indicating priority restoration and conservation actions.
了解树种对人为威胁的脆弱性对于高效规划恢复和保护工作非常重要。我们量化和比较了未来气候变化和当前的四种威胁（火灾、栖息地转换、过度放牧和过度开发）对秘鲁西北部和厄瓜多尔南部热带干旱森林中 50 种最常见树种的影响。我们使用集成建模方法来预测物种分布范围，利用免费获取的空间数据集来绘制威胁暴露情况，并开发了一种基于特征的评分方法来估计物种的敏感性，根据它们在确定物种对特定威胁的敏感性方面的预期重要性，使用不同的特征权重。物种特定的脆弱性地图是从暴露地图和敏感性估计的乘积构建的。我们发现，所有 50 个物种都面临着相当大的威胁，平均有 46%的物种分布范围对至少一种五种威胁中的一种表现出高或极高的脆弱性。我们的结果表明，目前的栖息地转换、过度开发和过度放牧水平对大多数研究物种构成的威胁大于气候变化。我们提出了一种针对特定物种的恢复和保护行动的空间明确规划策略，建议采取管理干预措施，重点关注（a）在气候变化和当前威胁低脆弱性地区进行就地保护和收集树种用于植树活动；（b）在气候变化脆弱性高的地区进行就地保护或种群转移；（c）在当前威胁脆弱性高但气候变化脆弱性低的地区进行积极种植或辅助再生，前提是采取干预措施降低威胁压力。我们提供了一个在线的、用户友好的工具，用于可视化脆弱性地图和指示优先恢复和保护行动的地图。
