基于栖息地指数的西北太平洋柔鱼渔获量估算

Estimated Catch of Neon Flying Squid(Ommastrephes bartramii)Based on Habitat Suitability Index in Northwest Pacific Ocean

西北太平洋柔鱼是世界大洋性经济柔鱼类之一,估算其渔获量是科学管理柔鱼资源的重要基础。根据2003-2008年8～10月西北太平洋柔鱼生产统计数据,结合环境遥感数据,包括海表温度(SST),海表温梯度(GSST)及海表高度(SSH),利用栖息地适宜性指数(HSI)模型定性描述资源密度分布与其栖息环境之间的关系,同时在假设捕捞努力量时空分布相同的情况下,建立了各作业渔区渔获量与HSI之间的关系。结果表明,单位渔区(经纬度0.5°×0.5°内周平均渔获量与HSI之间呈现显著的正相关,并建立了最适关系的指数模型,以及单位渔区内周最大可能渔获量与HSI之间的线性关系式。当HSI较低(0～0.1)或较高(0.9～1)时,其预测的渔获量相对误差较大,并对误差产生的原因进行了分析。研究结果表明,利用基于栖息地指数模型来预测柔鱼可能的渔获量是可行性。

Neon flying squid（Ommastrephes bartramii） inhabiting northwest Pacific Ocean is one of the economic oceanic squids in the world.The estimation of catch is important for the scientific resource management.The habitat suitability index（HSI） model was used to describe qualitatively the relationship between resource distribution and environmental factors in this study,which was run by integrating information of 3 environmental variables（sea surface temperature,SST;gradient of SST,GSST and sea surface height,SSH） obtained through environmental remote sensing and the fishery statistics of durations（Aug.-Oct.） of 6 years（2003—2008）.In addition,the relationship between HSI and the catch of diverse fishing sites was also established by assuming that an spatial and temporal distributiobn of the fishing effort in each sites is identical.It was found that the week average catch per unit fishing area（0.5° latitude×0.5° longitude） is positively correlated with HSI.An optimal exponential model describing such a correlation and a linear equation describing the relationshiop between week average catch and HSI were established.When HSI was either low（0~0.1） or high（0.9~1）,the predicted catch obviously deviated from the observed and the cause of this error was analyzed.It was feasible technologically and methodologically to predict squid catch with the habitat suitability index model.