Mapping the Drivers of Climate Change Vulnerability for Australia’s Threatened Species

Effective conservation management for climate adaptation rests on understanding the factors driving species’ vulnerability in a spatially explicit manner so as to direct on-ground action. However, there have been only few attempts to map the spatial distribution of the factors driving vulnerability to climate change. Here we conduct a species-level assessment of climate change vulnerability for a sample of Australia’s threatened species and map the distribution of species affected by each factor driving climate change vulnerability across the continent. Almost half of the threatened species assessed were considered vulnerable to the impacts of climate change: amphibians being the most vulnerable group, followed by plants, reptiles, mammals and birds. Species with more restricted distributions were more likely to show high climate change vulnerability than widespread species. The main factors driving climate change vulnerability were low genetic variation, dependence on a particular disturbance regime and reliance on a particular moisture regime or habitat. The geographic distribution of the species impacted by each driver varies markedly across the continent, for example species impacted by low genetic variation are prevalent across the human-dominated south-east of the country, while reliance on particular moisture regimes is prevalent across northern Australia. Our results show that actions to address climate adaptation will need to be spatially appropriate, and that in some regions a complex suite of factors driving climate change vulnerability will need to be addressed. Taxonomic and geographic variation in the factors driving climate change vulnerability highlights an urgent need for a spatial prioritisation of climate adaptation actions for threatened species.

用于气候适应的有效保护管理，需以空间明确的方式厘清驱动物种脆弱性的各类因素，以此指导实地保护行动。然而，目前针对气候变化脆弱性驱动因素的空间分布开展制图的研究仍寥寥无几。本研究针对澳大利亚受威胁物种样本开展物种尺度的气候变化脆弱性评估，并绘制了受各气候变化脆弱性驱动因素影响的物种在澳洲大陆的空间分布格局。经评估的受威胁物种中，近半数被认为易受气候变化影响：两栖动物是脆弱性最高的类群，其次依次为植物、爬行动物、哺乳动物与鸟类。分布范围更狭窄的物种，相比广布物种，更易表现出较高的气候变化脆弱性。驱动气候变化脆弱性的主要因素包括：遗传多样性偏低、依赖特定干扰制度，以及依赖特定水分制度或生境。各驱动因素所影响的物种，其地理分布在澳洲大陆内差异显著：例如，受低遗传多样性影响的物种多分布在人类活动主导的澳大利亚东南部，而依赖特定水分制度的物种则广泛分布于澳大利亚北部。本研究结果表明，气候适应相关保护行动需具备空间针对性；在部分区域，还需同时应对多种气候变化脆弱性驱动因素。气候变化脆弱性驱动因素在分类学与地理分布上的差异，凸显了为受威胁物种开展气候适应行动空间优先级划分的迫切需求。