非经典Beverton-Holt模型的数值计算

Numerical Calculation of Yield per Recruitment in Non-classical Beverton-Holt Model

针对经典Beverton-Holt模型计算单位补充量渔获量时对生长模型的限制,利用数值方法计算了不同生长模型时非经典Beverton-Holt模型的单位补充量渔获量。结果表明,本方法可以以较高的精度获得任一生长模型时的单位补充量渔获量的数值解;数值计算结果的误差主要是由体长与体重关系中的参数引起的;同一鱼种的不同生长模型的单位补充量渔获量会存在一定差异。为了获取更为可靠的评估结果,应采用最适生长模型。本文还以辽东湾小黄鱼和阿留申平鲉作为实例进行了分析。

Growth model is confined when the yield per recruitment （YPR） is calculated using the classical Beverton-Holt model. A numerical method is employed to compute the YPR when any growth model is adopted. The results show that the method in this study can obtain numerical value of YPR with a high accuracy when use of any growth model. The errors of numerical results are mainly caused by the parameters in the relationship between length and weight. There are some differences between the valves of YPR calculated with the different growth models for a particular species. It＇s more suitable to adopt the most appropriate growth model when calculating YPR with Beverton-Holt model so as to obtain more reliable assessment results. As example, YPR was analyzed for Pseudosciaena polyactis in Liaodong Gulf and Sebastes aleutianus in southeastern Alaska.