基于船位监控系统的拖网捕捞努力量提取方法研究

Method of extracting trawling effort based on vessel monitoring system

为了基于船位监控系统提取拖网捕捞努力量,通过统计航速获得3个峰值,拖网作业在第2个峰值,即1～2.1 m/s,拖网作业航向差一般在–50°～50°。利用航速、航向差阈值设定,把拖网船状态划分为慢速、作业、航行,然后提取出捕捞作业状态点,1 423艘拖网船共提取到处于捕捞状态的点318 433个,合计拖网捕捞时间15 921 h,利用反距离加权插值法生成捕捞强度分布变化趋势图。捕捞努力量在渔业资源研究中是重要的参考值之一,与传统的捕捞努力量计算方法相比,该方法具有实时、大范围、快速、分辨率高的特点,能够用于辅助渔业资源保护。

The purpose of this study was to extract trawling effort from the statistics of a vessel monitoring system. Using speed data, the results show that there are three peaks in trawling effort. The second peak is in the fishing state, and generally occurs at speeds between 1 m/s to 2.1 m/s. The heading difference is between ？50 and 50 degrees. Trawlers have three states, including low speed, fishing, and sailing, which can be distinguished by their thresholds of speed and heading differences. We extracted a total of 318 433 fishing-state points from 1 423 fishing vessels, and the total trawling time was 15 921 h. We used an inverse distance weighting interpolation method to generate change trends in the fishing intensity distribution. Fishing effort is an important reference value in fishery resource research. Compared with traditional fishing effort calculations, this method is characterized by real-time, large-scale, rapid, and high resolution. The results are applicable in the conservation of fisheries resources.