两类强度厄尔尼诺和拉尼娜事件对中国近海鲐鱼栖息地的影响

鲐鱼是中上层鱼类，具有较高经济价值，其种群受到气候和海洋环境的显著影响。本文根据2006-2015年7-9月中国远洋渔业数据中心提供的中国近海鲐鱼捕捞和海表温度以及海面高度两个关键环境因子的数据，构建了基于捕捞努力量的鲐鱼综合栖息地指数模型，分析研究了在不同强度厄尔尼诺和拉尼娜条件下鲐鱼栖息地适宜性的变动规律。通过计算和交叉验证，结果发现，基于算术平均法的栖息地模型能够较好地预测鲐鱼渔场栖息地适宜性指数。空间相关性结果表明，鲐鱼渔场主要作业海域范围内海表温度异常与栖息地指数值呈显著正相关关系，而海表面高度异常与栖息地指数值呈显著负相关关系。不同强度厄尔尼诺和拉尼娜事件对鲐鱼种群影响不同，具体表现为:相对于中强度厄尔尼诺事件（或中强度拉尼娜事件），超强厄尔尼诺事件（或强拉尼娜事件）驱动鲐鱼主要作业海域内温度下降（或上升），海面高度上升（或降低），鲐鱼渔场适宜栖息地面积显著减小（或增大），导致鲐鱼单位捕捞努力量渔获量骤减（或显著增加）。研究表明，中国近海鲐鱼栖息地适宜性与厄尔尼诺和拉尼娜事件显著相关，且随着异常气候事件强度的不同而发生变化。

Influence of El Niño and La Niña with different intensity on habitat variation of chub mackerel Scomber japonicas in the coastal waters of China

The chub mackerel Scomber japonicas is a pelagic species with high economic values. S. japonicas stock is significantly affected by climatic and environmental variability. In this study, an integrated habitat suitability index (HSI) mode was developed based on the fishing effort to evaluate the impacts of different intensity of El Niño and La Niña events on habitat suitability of S. japonicas by using the fishery data from July to September during 2006-2015 obtained from the data centers of Chinese distance water fishery combined with two key environmental variables including sea surface temperature (SST) and sea surface height (SSH). The results suggested that the HSI model based on the arithmetic mean method could accurately predict the habitat suitability on the fishing ground of S. japonicas based on the calculation and cross-validation. Spatial correlation analysis suggested that significant positive relationship was found between SSTA and the HSI of S. japonicas in space. While significant negative relationship was found between the SSH anomaly (SSHA) and the HSI on the fishing ground of S. japonicas in space. Different intensity of El Niño and La Niña events has different impacts on S. japonicas stock:comparing to the moderate El Niño events (or moderate La Niña events), the very strong El Niño event (or strong La Niña event) would yield decreased SSTA (or increased SSTA) and elevated SSHA (or reduced SSHA). The suitable habitat of S. japonicas would significantly decreased (or increased), leading to low CPUE (or high CPUE). Our findings indicated that the El Niño and La Niña events have closely relationship with the habitat suitability of S. japonicas in the coastal waters of China, however, the impacts on S. japonicas stock varied with the intensity of each anomalous climatic event.