中华鲟濒危状况与物种保护对策的评估分析

濒危等级是确定物种优先保护顺序和制订濒危物种保育策略的重要依据。结合历史资料以及近年的监测数据，对长江中华鲟种群繁殖群体及补充群体数量与质量，关键栖息地胁迫因素及胁迫强度等的全面梳理，总结出了1981年以来中华鲟种群及环境胁迫的变动趋势。参照IUCN物种濒危程度的划分准则建立了中华鲟物种濒危等级的划分标准；同时按照10年一组对该物种不同年代下的濒危状况进行评估。中华鲟在1983~1992年代进入濒危程度；在2003~2012年代进入极危程度。中华鲟物种的濒危等级取决于自身种群质量以及人类活动及环境结构变化等多方面的综合影响。人类活动和环境结构变化对中华鲟的胁迫呈现多样性与复杂性，且整体呈现一定的时间和空间尺度上的差异。最后，基于物种的濒危状况以及胁迫因素，分析了不同年代内的对策及效果，在此基础上提出了物种保护工作的构架和保护行动的优先顺序。

Endangered Levels and Conservation Options Evaluations for Chinese Sturgeon,Acipenser sinensis Gary

Chinese sturgeon (Acipenser sinensis Gary) is a large anadromous species, which matures in coastal waters and enters into rivers for spawning. This species was listed in the IUCN Red List as the endangered in 1996 and Critically Endengered in 2010. However, this kind of threatened categories of this species is questionable since no systematic criterion had been established for such classificaiton. This study established the classification criterion for endangered levels of this species on the basis of the IUCN Red List Categories and Criteria. Data from the biological changes (i.e., decline in the spawning population and spawning sizes, changes in the sex ratio) and the abiotic changes (i.e., habitat fragmentation, environmental changes, anthropogenic activities such as overfishing, river damming) were collected and analyzed. This study classified such data by decades to reveal the generational changes in Yangtze stocks of Chinese sturgeon and abiotic factors. Moreover, the biological and abiotic changes from the spawning grounds were used for the establishments of endangered categories of Chinese sturgeon, refering to the indexs of mature individuals and area of occupancy from the IUCN Red List Categories and Criteria. This study revealed that both spawning stocks and spawning sizes in the spawning grounds declined sharply since 1980s. Abiotic changes affected such decline varied over the decades. According to the endangered criterion esatblised in this study, Chinese sturgeon is endangered during the periods from 1983 to 1992 and critically endangered during the periods from 2003 to 2012. The endangered levels of Chinese sturgeon were affected by multiple factors, mainly the population quality, anthropogenic activities, and environmental changes. The influence of anthropogenic activities and changes in environmental structure on Chinese sturgeon demonstrates a highly diversity and complexity pattern. This type of influence varied with temporal and spatial scales. Based on the endangered status of Chinese sturgeon and affected factors, the countermeasures and effects in different decades were evaluated. Finally, the framework for the conservation options and strategies of Chinese sturgeon were proposed.