摘要: |
为研究长江口鱼类群落分类学多样性值(平均分类差异指数△+与分类变异差异指数∧+)的长期变动,根据1985~1986年、2004年及2010~2011年3个时期共12个航次长江口鱼类调查资料,分别计算了反映鱼类群落不同物种亲缘关系△+和亲缘关系均匀性∧+值。结果显示,2004年4个航次及2010~2011年3个航次鱼类△+均位于长江口鱼类群落总名录△+95%置信区间以下,与1985~1986年相比,2004年及2010~2011年各航次平均△+均较低;∧+的分布格局则与△+有所不同,主要表现为12个航次的∧+均在95%置信区间内。长江口鱼类群落△+的降低跟过度捕捞、环境污染、生境破坏等有关,其下降也反映出群落种类组成在形态亲缘关系上更加接近。 |
关键词: 长江口 鱼类群落分类学 多样性 长期变动 |
DOI: |
分类号: |
基金项目:国家973项目(2010CB429005) |
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Analysis of taxonomic diversity of fish community in Yangtze River estuary |
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Abstract: |
For studying the long-term changes in taxonomic diversity (average taxonomic distinctness and variations in taxonomic distinctness) of fish community in Yangtze River estuary, fish species recorded at three periods (1985~1986, 2004, 2010~2011) were used to estimate the △+ and ∧+ for respective survey. The results showed that △+ in 2004 and 2010~2011 (except the spring survey) fell below the 95% probability limits for △+ of all fish species from Yangtze River estuary. Moreover, the decreasing trends in △+ were also observed. However, patterns of variation in ∧+ was different from △+, as all ∧+ distributed in the 95% probability limits for∧+ of all fish species. Declines in △+ of Yangtze River estuary may be a result of overfishing, pollution and habitat destruction, as shown in closer relationships among fish species, implying for increased niche similarity between species and potential loss of stability or resilience of the community. |
Key words: Yangtze River estuary Fish community Taxonomic diversity Long-term changes |