人工放流对武陵山区中国大鲵遗传多样性与生态适合度的影响研究

迁地保护对濒危动物种群恢复至关重要。然而，由于奠基者效应及圈养环境改变，以人工增殖放流为主要实践的迁地保护通常蕴含着潜在的遗传与生存风险。我国特有极度濒危两栖动物中国大鲵即面临典型的保护困境：由于缺乏遗传管理，广泛实施多年的人工放流可能对原生种群遗传组成带来巨大冲击，遗传杂合度也可能对放流后代生存适应产生显著影响，从而使放流努力趋于无效甚至适得其反。本研究拟对首个国家级大鲵保护区所在地且在国内最先实施人工放流的武陵山区展开研究，一方面借助线粒体与微卫星等分子标记技术，全面揭示当前区域内纯野生土著种群、受放流干扰野外种群和人工养殖种群的遗传多样性现状；另一方面通过首次构建大鲵不同遗传家系，开展遗传杂合度与生态适合度的相关性研究，明确遗传组成对大鲵繁殖力、环境适应力和抗病力的影响规律。综合野外调查与遗传适应研究结果，提出首个武陵山区大鲵人工放流的遗传管理方案，并以此推动全国大鲵保护策略的制定。

Ex situ conservation has been playing critical role in the population recovery of threatened animals. However, the main practice of ex situ conservation, which we call it the artificial reproduction and reintroduction, has potential genetic and survival risks; it mainly results from the effect of small founder populations and the changed surroundings alongside with captive rearing. The Chinese giant salamander (Andrias davidianus), a critically endangered and endemic amphibian, is getting into such a protective dilemma. Because of the absence of genetic management for long time, the reintroduced populations of Andrias davidianus despite released into the wild for many years, would possibly impact significantly to the genetic composition of the wild populations. Meanwhile, the genetic heterozygosity of source populations, would also produce severely potential effects to the survival and adaptation of the offspring that generated by the reintroduced populations. Together, these unexpected consequences might drive the endeavor of artificial reintroduction invalid or at cross purpose. This study we focus on the Wuling mountains area, where locates the first national nature reserve, and also practices the first domestic reintroduction of Andrias davidianus. On one hand, based on the molecular markers of mitochondrial DNA and simple sequence repeats, we attempt to reveal the comprehensive genetic diversity of Andrias davidianus among the pure native wild population, reintroduction disturbed wild population, and artificial reared population. On the other hand, through the construction of different families with varied degree of genetic distances, we’d like to carry out the first analysis of heterozygosity-fitness correlations in Andrias davidianus. We expect to uncover the patterns of genetic compositions to the capacities of reproduction, environmental adaptation, and disease resistance. In combination of field investigation and genetic-adaptation results in this study, we will propose the first genetic management program in Wuling mountain area, and promote the scientific plan of the national conservation strategy of Andrias davidianus.