本研究从刺网选择性对鱼类表型性状的影响入手，应用数值模拟方法，模拟了一个具有一定体长特征的鱼类种群，利用具有多项选择参数（曲线标准差σ，最适体长l0，选择性因素Ro）的刺网曲线对其进行长期捕捞作用，并在去除捕捞的情况下探讨这种影响的稳定性。结果表明，刺网捕捞作业长期作用于鱼类种群，会对种群体长组成产生深远的影响，开发率（D越大，效果越明显。当刺网最适捕捞体长与初始种群优势体长重合时（l0=15），造成种群体长分布峰值的分化；如果l0〉15，则导致种群体长组成向小型化方向偏移；反之则会造成种群体长组成向大型化方向偏移；而且这种影响可能伴随遗传因素，具有不可逆性。%Based on models used in fishery biology, quantitative genetics, as well as numerical simulation methods, we developed a numerical simulation model to investigate whether long-term use of gillnet may affect the phenotypic traits （such as body length） of a fish population. In our simulation, we modeled a fish population that had a certain body length; then by varying a host of variables （α,l0, R0）, we explored the effect of long-term gillnet fishing as well as examined the stability of such effect after the fishing pressure was removed. The simulation results suggested that long-term fishing pressure was able to affect the characteristics of the fish population, i.e., the lager the exploitation rate （E）, the more distinct the effect. Furthermore, this impact was probably irreversible for a population that had experienced long-term fishing pressure.
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