中文摘要：

研究一类周期环境中基于个体尺度分布的种群资源模型的最优收获率问题.运用泛函分析方法证明了最优策略的存在性,借助非线性分析中的切锥-法锥技巧导出了最优策略的结构,为模型应用奠定了理论基础.

英文摘要：

This paper is concerned with the optimal harvesting for a size-structured population model in a periodic environment. Applying a functional approach, we demonstrate the existence of the optimal strategies, and derive the structure of the optimal controls by means of tangent and normal cones. The results pave the way for practical applications of the model.