基于跨组生长与生态平衡种群模型的最优收获

Optimal Harvesting of Discrete Size-dependent Population Based on Ecological Balance and Group-crossing Growth

考虑一类跨组生长的离散尺度结构种群模型,个体按照尺度由小到大被分为3个小组,既考虑跨组生长也顾及生长迟缓情形.在生态平衡约束下研究最优收获问题,应用凸集上的函数极值理论导出了两阶段模式的最优收获策略,具体收获比例由模型参数确定.研究结论表明,资源管理领域的"双窗原理"在一定条件下对非正常演化的尺度结构种群仍然成立.

This paper considers a class of discrete size-structured population model with group-crossing growth,and the individual is divided into three groups from small to large.Both the cross and slow growth are taken account.Also,it investigates an optimal harvesting problem under the constraint of ecological balance.By means of the extreme theory of functions on convex sets,the optimal strategy is obtained and the specific harvest ratio is determined by the model parameters.The conclusion shows that＂double windows principle＂in the resource management field is still established for the non-normal evolution of size-structured population under certain conditions.