李德伟,张 龙,王 洋,朱文斌
(浙江省海洋水产研究所,农业部重点渔场渔业资源科学观测实验站,
浙江省海洋渔业资源可持续利用技术研究重点实验室,浙江 舟山316021)
摘要:根据2013年渔季在阿根廷外海公海海域的渔业生产数据,结合时间、空间、表温、水深和流速等环境数据,建立广义可加模型(GAM),对2013年夏秋季阿根廷滑柔鱼(Illex argentinus)单位捕捞努力量渔获量(CPUE)与时空因素、环境因子的关系进行研究。结果表明,优化后的GAM模型对CPUE总偏差解释率为56.10%,其中作业日期、表温、水深和流速对CPUE影响较大。根据 AIC准则,包含上述4个显著变量的广义可加模型为最佳模型,其pseduo系数PCf值为0.487,AIC值为660.688,表明其具有较好的拟合度。各环境因子(海水表温、水深和流速)中,水深与研究区域CPUE的关系最为密切,阿根廷滑柔鱼渔场(阿根廷外海公海)适宜水深为分别为100~120 m和250~500 m,适宜表温为8~14℃,最适表温为12~14℃。GAM模型分析结果表明,影响CPUE的因子按重要性依次为作业日期>水深>表温>流速。
关键词:阿根廷滑柔鱼;西南大西洋;广义加性模型(GAM);资源评估
Study on the relationship between Illex argentinus CPUE and environmental factors based on GAM
LI Dewei, ZHANG Long, ZHU Wenbin, WANG Yang
( Marine and Fishery Research Institute of Zhejiang Ocean University, Scientific Observing and Experimental Station of Fishery Resources for Key Fishing Grounds, Ministry of Agriculture; Key Laboratory of Sustainable Utilization of technology Research for Fishery Resource of Zhejiang Province, Zhoushan 316021, China)
Abstract: Based on the capture data of Argentina offshore in summer and autumn of 2013, combined with the data of environment including date, space, SST, water depth, flow velocity, etc, we established generalized additive models (GAM) with Illex argentinus catches per unit fishing effort (CPUE), temporal spatial factors and environmental factors to study the relationship among them. The results showed that GAM of the accumulation explained for CPUE was 56.10%, there were four factors affecting on the CPUE greatly, which were operation date, SST, depth and flow velocity. According to the Akaike information criterion (AIC) guidelines, the optimal model included these four significant variables, its PCf (pseudo coefficient) value was 0.487, and AIC value was 660.688, which indicated that the model has a better fitness. Among environmental factors, the relationship between depth and the CPUE of studied area was most closely, the appropriate depth of Illex argentinus fishing grounds was 250-500 meters, suitable SST ranged from 8-14℃, and the optimum SST was 12-14℃. Stepped GAM model analysis showed that influencing factors of CPUE was date, depth, SST and flow velocity according to their importance.
Key words: Illex argentines; summer and autumn; GAM; Southwest Atlantic Ocean