气候变化对中国近海8种中上层鱼类潜在生境分布的影响

随着底层和近底层渔业资源的衰退，海洋中上层鱼类在我国海洋捕捞业中逐渐占据重要的地位。预测气候变化情景下中上层经济鱼类的潜在生境分布及其变化规律，可为应对气候变化的鱼类栖息地保护和渔业生态系统管理提供重要科学依据。采用物种分布模型模拟并预测现状及2050年两种气候变化情景下8种中上层经济鱼类在中国近海的潜在分布，通过分布区的收缩-扩张情形和质心迁移距离定量分析气候变化对鱼类空间分布格局的影响。结果表明：(1)模型预测结果良好，各组模型的AUC值均高于0.85,影响目标鱼类潜在分布的主要驱动因子为海水表层温度和溶解氧；(2)8种中上层经济鱼类中，羽鳃鲐(Rastrelliger kanagurta)、鳓鱼(Ilisha elongata)等种类生境分布偏南，气候变化情景下分布北界可扩展至长江口，而鳀鱼(Engraulis japonicus)、青鳞小沙丁鱼(Sardinella zunasi)等种类主要分布在我国北方海域，气候变化情景下生境南缘边界退缩明显；(3)整体来看RCP8.5情景下的空间分布变化率大于RCP2.6情景，其中蓝圆鲹(Decapterus maruadsi)、青鳞小沙丁...

Impact of climate change on the potential habitat distributions of eight pelagic fishes in the coastal waters of China

Pelagic fishes are becoming more and more important in marine fisheries, with the decline of demersal fishes. The significantly scientific basis can be provided for fish habitat protection and fishery ecosystem management in response to climate change, through prediction of potential habitat distribution and variation of species of pelagic fishes under climate change scenarios. In this study, the potential distribution and habitat suitability for 8 commercially pelagic fish under different climate change scenarios were simulated using species distribution model. The effects of climate change on the spatial distribution framework of pelagic fish were analyzed by constriction-expansion and centroid migration distance in the distribution area. The results showed that:(1) the AUC(Area Under the Curve) values of each model were higher than 0.85, suggested that the accuracy of the model was satisfactory. The sea surface temperature and dissolved oxygen were the main driving factors affecting the potential distribution of target fishes. (2) Among the 8 target pelagic fishes, Rastrelliger kanagurta, Ilisha elongata, etc were distributed in south, which could move northward to the Yangtze River Estuary under climate change scenarios. Engraulis japonicus, Sardinella zunasi, etc were mainly distributed in the northern China seas, and the southern edge of their potential habitats obviously shrunk when climate changed. (3) Overall, the distribution pattern changes were greater under RCP8.5 scenario than RCP2.6 scenario. Species like D. maruadis and S. zunasi may have expansion habitats as potential winners, while R. kanagurta, E. japonicus, etc. may be potential losers. The potential habitat of E. japonicus may have the most reduction. (4) The potential habitats of most pelagic fish may move northwards, however S. zunasi tends to move southward. The average northward distance of habitat centroids under RCP2.6 is predicted to be 89.43 kilometers, and the distance under RCP8.5 is 182.95 kilometers.