Durrell Institute of Conservation and Ecology (DICE), School of Anthropology and Conservation, University of Kent, Canterbury, CT2 7NR, UK.
Leibniz Institute for Zoo and Wildlife Research (IZW), Alfred-Kowalke-Straße 17, 10315, Berlin, Germany.
Glob Chang Biol. 2015 Aug;21(8):2891-904. doi: 10.1111/gcb.12814. Epub 2015 Jan 6.
Habitat loss and climate change pose a double jeopardy for many threatened taxa, making the identification of optimal habitat for the future a conservation priority. Using a case study of the endangered Bornean orang-utan, we identify environmental refuges by integrating bioclimatic models with projected deforestation and oil-palm agriculture suitability from the 1950s to 2080s. We coupled a maximum entropy algorithm with information on habitat needs to predict suitable habitat for the present day and 1950s. We then projected to the 2020s, 2050s and 2080s in models incorporating only land-cover change, climate change or both processes combined. For future climate, we incorporated projections from four model and emission scenario combinations. For future land cover, we developed spatial deforestation predictions from 10 years of satellite data. Refuges were delineated as suitable forested habitats identified by all models that were also unsuitable for oil palm - a major threat to tropical biodiversity. Our analyses indicate that in 2010 up to 260,000 km(2) of Borneo was suitable habitat within the core orang-utan range; an 18-24% reduction since the 1950s. Land-cover models predicted further decline of 15-30% by the 2080s. Although habitat extent under future climate conditions varied among projections, there was majority consensus, particularly in north-eastern and western regions. Across projections habitat loss due to climate change alone averaged 63% by 2080, but 74% when also considering land-cover change. Refuge areas amounted to 2000-42,000 km(2) depending on thresholds used, with 900-17,000 km(2) outside the current species range. We demonstrate that efforts to halt deforestation could mediate some orang-utan habitat loss, but further decline of the most suitable areas is to be expected given projected changes to climate. Protected refuge areas could therefore become increasingly important for ongoing translocation efforts. We present an approach to help identify such areas for highly threatened species given environmental changes expected this century.
生境丧失和气候变化对许多受威胁的分类群构成了双重威胁，因此确定未来的最佳生境成为保护的优先事项。我们以濒危的婆罗洲猩猩为例，通过将生物气候模型与 20 世纪 50 年代至 2080 年的森林砍伐和油棕农业适宜性预测相结合，确定了环境避难所。我们结合最大熵算法和栖息地需求信息，预测了现今和 20 世纪 50 年代的适宜栖息地。然后，我们仅在模型中结合土地覆盖变化、气候变化或这两个过程的组合，将预测结果扩展到 2020 年代、2050 年代和 2080 年代。对于未来的气候，我们结合了四个模型和排放情景组合的预测结果。对于未来的土地覆盖，我们利用 10 年的卫星数据开发了空间森林砍伐预测。避难所被划定为所有模型都确定的适宜森林栖息地，这些栖息地也不适宜油棕生长，油棕是热带生物多样性的主要威胁。我们的分析表明，到 2010 年，婆罗洲核心猩猩分布区内有多达 26 万平方公里的土地适宜作为栖息地；这一数字自 20 世纪 50 年代以来下降了 18-24%。土地覆盖模型预测，到 2080 年，这一数字将进一步下降 15-30%。尽管未来气候条件下的栖息地范围因预测结果而异，但大多数预测结果都存在共识，尤其是在东北部和西部地区。在所有预测结果中，仅气候变化导致的栖息地丧失到 2080 年平均达到 63%，但如果同时考虑土地覆盖变化，则达到 74%。避难区的面积根据使用的阈值而有所不同，在 2000-42000 平方公里之间，其中 900-17000 平方公里在当前物种分布范围之外。我们证明，阻止森林砍伐的努力可以减轻一些猩猩栖息地的丧失，但考虑到对气候的预计变化，最适宜地区的进一步下降是不可避免的。因此，保护区可能会变得越来越重要，因为要进行持续的转移工作。我们提出了一种方法，以帮助确定在本世纪预期的环境变化下，高度濒危物种的这些区域。
