2005—2016年中国东海鲐鱼渔场的时空分布及与海表面温度的关联

鲐鱼(Scomber japonicus)是中上层经济鱼类,也是我国近海重要的捕捞对象,其资源分布受不同尺度气候和海洋环境变化的显著影响。本文根据2005-2016年7-9月中国远洋渔业数据中心提供的我国东海鲐鱼捕捞数据,结合关键因子海表面温度(sea surface temperature,SST),计算各年鲐鱼渔场经纬度重心,量化鲐鱼渔场重心的时空变化。进一步分析了捕捞努力量在经度、纬度以及SST上的分布规律,并基于聚类法筛选出代表年份评估异常气候事件对鲐鱼渔场内SST及渔场重心时空分布的影响。研究结果显示,鲐鱼渔场重心具有显著的年际和月间变化,7-9月渔场逐渐向东北方向移动,且主要分布在SST为25~28°C范围内。聚类分析将各月份渔场重心分为四类,其中2007和2015年渔场分布具有显著差异。此外,鲐鱼渔场内SST与尼诺指数具有显著的正相关关系,且代表年份2007和2015年分别对应拉尼娜事件和厄尔尼诺事件,当拉尼娜事件发生时,渔场内SST上升,渔场重心逐渐北移；而厄尔尼诺事件发生时,渔场内SST下降,渔场重心主要分布在南部海域。研究表明,中国东海鲐鱼渔场时空分布受到厄尔尼诺和拉尼娜调控的海表温度变化的显著影响。

Spatio-temporal distribution of chub mackerel Scomber japonicus in the East China Sea during 2005-2016 and its relationship with sea surface temperature

Chub mackerel (Scomber japonicus) is a pelagic economically important species and is an important fishing target for Chinese coastal fisheries. The distribution of S. japonicus is significantly affected by climatic and environmental conditions at different scales. Based on the fisheries data of S. japonicus from July to September during 2005-2016 provided by National Data Center of Distant-water Fisheries of China, combined with the key environmental factor sea surface temperature (SST) data, this study quantified the temporal and spatial changes of fishing ground of S. japonicus on the analysis of determining the longitudinal and latitudinal gravity centers of fishing effort. Additionally, the distribution of the fishing ground in relation to longitude, latitude and SST was analyzed. Furthermore, the representative years were selected by cluster analysis to evaluate the impacts of abnormal climate events on the spatial and temporal distribution of SST and gravity centers of fishing ground for S. japonicas in the East China Sea. The results showed that there was significant interannual and monthly variation in gravity centers of fishing ground for S. japonicas in the East China Sea. The fishing ground gradually moved northeastward from July to September, which mainly occurred in the SST ranging from 25^oC to 28^oC. Cluster analysis suggested that gravity centers of fishing ground in each month were divided into four categories, and significant difference was found between 2007 and 2015 in each month. Moreover, a statistically significant positive correlation was found between SST anomaly on the fishing ground of S. japonicas and ocean Ni?o index. A La Ni?a event occurred in 2007 and an El Ni?o event occurred in 2015. When the La Ni?a event occurred, the SST on the fishing ground increased, and the gravity center of the fishing ground gradually moved northward; while the El Ni?o event occurred, the SST on the fishing ground largely decreased, and the gravity center of the fishing ground mostly located in the southern waters on the fishing ground. Our findings indicated that spatio-temporal distribution of S. japonicas in the East China Sea was strongly regulated by the impacts of the El Ni?o and La Ni?a-driven SST changes on the fishing ground.