Nüchel Jonas, Bøcher Peder Klith, Xiao Wen, Zhu A-Xing, Svenning Jens-Christian
1Section for Ecoinformatics & Biodiversity, Department of Bioscience, Aarhus University, Ny Munkegade 114, 8000 Aarhus, Denmark.
2Sino-Danish Center for Education and Research, Beijing, 100101 China.
Biodivers Conserv. 2018;27(6):1517-1538. doi: 10.1007/s10531-018-1507-0. Epub 2018 Jan 23.
Many threatened species have undergone range retraction, and are confined to small fragmented populations. To increase their survival prospects, it is necessary to find suitable habitat outside their current range, to increase and interconnect populations. Species distribution models may be used to this purpose and can be an important part of the conservation strategies. One pitfall is that such mapping will typically assume that the current distribution represents the optimal habitat, which may not be the case for threatened species. Here, we use maximum entropy modelling (Maxent) and rectilinear bioclimatic envelope modelling with current and historical distribution data, together with the location of protected areas, and environmental and anthropogenic variables, to answer three key questions for the conservation of a highly endangered genus of primates consisting of five species of which three are endemic to China, one is endemic to China and Myanmar and one is endemic to Vietnam; Which environmental variables best predict the distribution? To what extent is living in an anthropogenically truncated niche space? What is the genus' potential distribution in the region? Mean temperature of coldest and warmest quarter together with annual precipitation and precipitation during the driest quarter were the variables that best explained distribution. The historical records were generally in warmer and wetter areas and in lower elevation than the current distribution, strongly suggesting that today survives in an anthropogenic truncated niche space. There is 305,800-319,325 km of climatic suitable area within protected areas in China, of which 96,525-100,275 km and 17,175-17,550 km have tree cover above 50 and 75%, respectively. The models also show that the area predicted as climatic suitable using Maxent was 72-89% larger when historical records were included. Our results emphasise the importance of considering historical records when assessing restoration potential and show that there is high potential for restoring to parts of its former range.
许多濒危物种的分布范围已经收缩，仅存于小型、碎片化的种群中。为增加它们的生存几率，有必要在其当前分布范围之外寻找适宜栖息地，以扩大种群数量并实现种群间的连通。物种分布模型可用于此目的，并且可能成为保护策略的重要组成部分。一个潜在问题是，此类分布图通常会假定当前分布代表了最佳栖息地，但对于濒危物种而言可能并非如此。在此，我们使用最大熵模型（Maxent）以及结合当前和历史分布数据、保护区位置、环境和人为变量的直线生物气候包络模型，来回答有关一个极度濒危灵长类属保护的三个关键问题，该属包含五个物种，其中三个为中国特有，一个为中国和缅甸特有，一个为越南特有；哪些环境变量能最佳预测其分布？生活在人为截断的生态位空间中的程度如何？该属在该地区的潜在分布是怎样的？最冷和最暖季度的平均温度、年降水量以及最干燥季度的降水量是最能解释其分布的变量。历史记录显示该属通常分布在比当前分布更温暖、湿润且海拔更低的地区，这有力地表明其如今生存在一个人为截断的生态位空间中。中国保护区内有305,800 - 319,325平方千米的气候适宜区域，其中分别有96,525 - 100,275平方千米和17,175 - 17,550平方千米的区域树木覆盖率高于50%和75%。模型还表明，当纳入历史记录时，使用Maxent预测的气候适宜面积比不考虑历史记录时大72 - 89%。我们的结果强调了在评估恢复潜力时考虑历史记录的重要性，并表明该属在其部分过去分布范围内具有很高的恢复潜力。
