Combined climate change and dispersal capacity positively affect Hoplobatrachus chinensis occupancy of agricultural wetlands

Global warming is one of the major factors contributing to the decline and extinction of amphibian populations worldwide, and modeling can help understand the mechanisms and trends of its effects. Here, we used MaxEnt and MigClim models to predict the impact of future climate change on habitat suitability for Hoplobatrachus chinensis, a species of anuran widespread in natural and modified landscapes across eastern Indomalaya, under different climate change scenarios and dispersal patterns. We also calculated the overlap in suitable habitat between natural habitat and agricultural wetlands for the species. While the distribution of many anurans is primarily influenced by precipitation levels, our results indicate that temperature is a key environmental variable affecting the distribution of H. chinensis. Under current and future climate change scenarios, we found a positive correlation between increasing temperatures and habitat suitability for H. chinensis, with the suitable habitat for the species expanding northward by 2060, while maintaining southern habitat suitability. Comparing unlimited and limited dispersal modes, our model supported the ability of H. chinensis to track shifts in suitable habitats under climate change scenarios, given a 15 km dispersal ability per generation. Finally, we demonstrated that there is only a 25.18% overlap between current potential suitable habitats of H. chinensis and agricultural wetlands. In conclusion, our results suggest that climate change will have a positive impact on the expansion of suitable habitat for H. chinensis, even given their limited dispersal capacity. Our predictions offer important guidance for the conservation of H. chinensis, especially the integrated role of natural and agricultural wetlands, such as rice paddy fields.

全球变暖是全球范围内两栖动物种群衰退与灭绝的主要诱因之一，而建模研究有助于解析其影响的机制与趋势。本研究采用MaxEnt与MigClim模型，在不同气候变化情景与扩散模式下，预测未来气候变化对中国虎纹蛙（Hoplobatrachus chinensis）栖息地适宜性的影响——该物种为广泛分布于印度马来亚东部自然与人工改造景观中的无尾目动物（anuran）。本研究同时计算了该物种适宜栖息地在自然生境与农业湿地间的重叠度。尽管多数无尾目动物的分布主要受降水水平调控，但本研究结果显示，温度才是影响中国虎纹蛙分布的关键环境变量。在当前及未来气候变化情景下，我们发现温度升高与中国虎纹蛙的栖息地适宜性呈正相关，至2060年该物种的适宜栖息地将向北扩张，同时其南部适宜生境仍得以保留。通过对比无限扩散与有限扩散两种模式，本研究模型证实：在每世代扩散能力为15公里的前提下，中国虎纹蛙具备追踪气候变化下适宜栖息地变迁的能力。最后，本研究证实，当前中国虎纹蛙的潜在适宜栖息地与农业湿地的重叠度仅为25.18%。综上，本研究结果表明，即便考虑到中国虎纹蛙有限的扩散能力，气候变化仍将对其适宜栖息地的扩张产生积极影响。本研究的预测结果可为中国虎纹蛙的保护工作提供重要参考，尤其是针对自然生境与农业湿地（如稻田）的整合保护策略。