大型年长鱼类对海洋生态系统生物资源养护的作用

随着人口增长和渔业资源需求的上升，人类沿着食物网营养级自上向下捕捞渔业资源的趋势仍在持续，导致海洋生物多样性丧失及其生态功能与服务价值迅速下降。由捕捞活动造成的渔业诱导进化进一步导致鱼类资源小型化已受到国内外学者的广泛关注。从大型年长鱼类这一独特视角出发，综述了大型年长鱼类在种群繁衍过程中的作用，其具备巨大的繁殖能量输出、丰富的亲本繁殖经验以及强大的年龄组繁殖力贡献，更有利于种群的延续；大型年长鱼类对于初次性成熟亲鱼生殖洄游具有一定的引领作用，并在季节性集群繁殖过程中占据主导地位，可通过抑制小个体同类繁殖维护种群结构的稳定；大型年长鱼类在生态系统中更是占据了较高营养级和广阔的生态位宽度，面对生态环境的改变，具有更强的适应调控能力；大型年长鱼类在种群基因交流过程中亦起到十分关键的作用。保护大型年长鱼类更有利于鱼类种群的快速恢复，这为生物资源养护和渔业管理政策制定方面提供了一定的参考。

An ecosystem perspective on fisheries conservation based on the importance of the big old fish

With the increase of population and the demand of fishery resources, the trend of human fishing from high to low trophic level is still continuing, which could threat the marine biodiversity and benefits. It has been widely concerned that fishery-induced evolution (FIE) caused by overfishing has led to the general miniaturization of fishes. In this paper, we reviewed the role of big old fish in the process of population reproduction. The big old fish has huge reproductive-energy output and rich parental experience, which is more conducive to the continuation of their population. We believe that big old fish has played a leading role in the breeding migration of the first sexual maturation broodstock. The big old fish also can maintain the stability of the population structure by inhibiting the reproduction of small fish. Besides, the big old fish occupies a higher trophic level and expansive niche breadth in the ecosystem, which leads to stronger adaptability to respond to environmental changes. The big old fish also plays a key role in the process of population gene exchange. Therefore, it is indicated that the protection of big old fish would be more conducive to the rapid recovery of fish population, which can provide useful information for biological resources conservation and fishery administration.