Abstract：
Neotropical seasonal dry forest (NSDF) is one of the most threatened ecosystems according to global climate change predictions. Nonetheless, few studies have evaluated the global climate change impacts on diversity patterns of NSDF plants. The lack of whole biome-scale approaches restricts our understanding of global climate change consequences in the high beta-diverse NSDF. We analysed the impact of global climate change on species distribution ranges, species richness, and assemblage composition (beta diversity) for 1,178 NSDF species. We used five representative plant families (in terms of abundance, dominance, and endemism) within the NSDF: Cactaceae, Capparaceae, Fabaceae, Malvaceae, and Zygophyllaceae. We reconstructed potential species distributions in the present and future (2040-2080), considering an intermediate Shared Socioeconomic Pathway and two dispersal ability assumptions on the taxa. Using a resource use scores index, we related climate-induced range contractions with species\' water stress tolerance. Even under a favourable dispersal scenario, species distribution and richness showed future significant declines across those sites where mean temperature and precipitation seasonality are expected to increase. Further, changes in species range distribution in the future correlated positively with potential use of resources in Fabaceae. Results suggest that biotic heterogenization will likely be the short-term outcome at biome scale under dispersal limitations. Nonetheless, by 2080, the prevailing effect under both dispersal assumptions will be homogenization, even within floristic nuclei. This information is critical for further defining new areas worth protecting and future planning of mitigation actions for both species and the whole biome.
摘要：
根据全球气候变化预测，新热带季节性干旱森林（NSDF）是受威胁最大的生态系统之一。尽管如此，很少有研究评估全球气候变化对NSDF植物多样性模式的影响。缺乏完整的生物群落尺度方法限制了我们对高β多样性NSDF中全球气候变化后果的理解。我们分析了全球气候变化对物种分布范围的影响，物种丰富度,和1178个NSDF物种的组合组成(β多样性)。我们使用了五个有代表性的植物家族(就丰度而言，支配地位,和地方性）在NSDF中：仙人掌科，仙人掌科,豆科，锦葵科,和菊科。我们重建了当前和未来(2040-2080)的潜在物种分布，考虑中间共享社会经济途径和对分类单元的两个扩散能力假设。使用资源使用分数索引，我们将气候引起的范围收缩与物种的水分胁迫耐受性相关联。即使在有利的分散情况下，物种分布和丰富度显示，在平均温度和降水季节性预计会增加的地点，未来会出现显着下降。Further,未来物种范围分布的变化与豆科资源的潜在利用呈正相关。结果表明，在分散限制下，生物异质性可能是生物群落规模的短期结果。尽管如此，到2080年，两种分散假设下的主要影响将是均质化，甚至在植物区系核内。这些信息对于进一步确定值得保护的新领域以及未来为物种和整个生物群落制定缓解行动的计划至关重要。
