淀山湖鱼类生物多样性调查样本量的优化设计

样本量大小影响估算鱼类种群动态和鱼类群落特征的准确性和精确度.本文以淀山湖渔业资源调查为例,研究估算淀山湖鱼类群落特征所需的样本量大小.2010年7月—2011年6月研究期间每月进行一次淀山湖渔业资源调查,共捕获14科45种鱼类.利用重采样方法,估算淀山湖渔业资源调查最优调查频次和最佳站点数.结果表明: 在淀山湖渔业资源调查中,站点数和调查频次呈负相关关系;保持95%的探测率探测90%的物种,每年调查11和12次相应需要设置21和19个站点.Shannon多样性指数随着每次调查站点数的增多而变大,增长到一定程度之后逐渐趋于稳定.淀山湖鱼类群落的物种多样性调查最佳站点数为21.本文的研究方法和结果可以为其他类似研究提供借鉴.

Optimal design of sample size for estimating species richness of fishes in Dianshan Lake,China

Sample size plays a significant role in determining accuracy and precision for estimates of fish population dynamics or fish communities. A fisheries survey that estimated the fish community in Dianshan Lake was conducted as a case study to determine the necessary sample size for such estimates. Monthly surveys of 24 survey stations in Dianshan Lake were conducted from July, 2010 to June, 2011, resulting in the collection of 45 fish species from 14 families. A resampling technique was used to estimate the optimal survey times and number of survey stations for a Dianshan Lake fishery survey. Results showed a negative relationship between the number of stations per survey and survey times per year. To maintain a 90% fixed percentage of fish species detection and 95% fixed probability of detection within the fishery survey, the required sample sizes were 19 and 21 stations per survey and 12 and 11 survey times per year, correspondingly. The Shannon diversity index increased with the number of stations before reaching equilibrium, therefore, the optimal survey stations for estimating fish biodiversity of the Dianshan Lake fishery was determined to be 21 stations. This study provided a framework for determining the optimal sampling effort in similar studies at other locations.