莱州湾渔业水域游泳动物群落特征

根据2010~2011年莱州湾渔业水域春季、夏季和秋季共6个航次的调查资料,调查分析了该水域游泳动物的种类组成,计算分析了游泳动物群落特征的年度和季节变化,包括相对重要性指数(IRI)、Margalef物种丰富度指数(D)、Shannon-Wiener物种多样性指数(H')、Pielou物种均匀度指数(J)、鱼类群落季节更替指数(AI)、迁移指数(MI);并利用数量生物量比较曲线(ABC曲线)评价游泳群落受干扰程度,利用扫海面积法估算游泳动物资源密度。结果表明,调查共捕获游泳动物99种,其中鱼类55种,甲壳类40种,头足类4种;优势种分析表明虾虎鱼和枪乌贼类成为主要捕捞物种,优势种正逐步演变为更为小型化的中上层鱼类和无脊椎动物,虾蟹类和头足类的比例进一步提高。多样性分析表明,各类生物多样性指数变化不大,季节更替和迁移指数仅在2010年春季相对变化较大;ABC曲线分析表明,游泳动物群落正处于严重干扰;游泳动物资源密度均值在重量和数量上分别达到635.9 kg·hm-2和43.8×103ind·hm-2,资源情况有所改善,但渔获物小型化、低质化现象明显。综合来看,调查水域游泳动物优势种变化较大,资源继续向小型化中上层鱼类方向演变,且群落受到干扰较为严重。研究结果可为系统开展莱州湾海洋生物恢复和生态修复工作与研究提供基础信息。

On community characteristics of nekton in fishery areas in the Laizhou Bay

Based on the survey data in fishery areas of the Laizhou Bay in 2010-2011,the structure of nekton and the annual and seasonal changes of community characteristics were analyzed.The indices of community characteristics included Index of Relative Importance (IRI),Margalef richress index (D),Shannon-Wiener diversity index(H'),Pielou evenness index (J) and the seasonal alternation and migration indices of nekton.Community disturbance was assessed by using the abundance biomass curve (ABC curve).Resource density was estimated by using the sweep-area method.The results indicated that 99 species were identified,including 55 fishes,40 crustaceans and 4 cephalopods.The analysis of IRI showed that Eucyclogobius newberryi(Gobiidae) and squid (Loliginidae) had become the main catch.Dominant species gradually evolved into a more miniaturization of upper-middle fish and invertebrates.The proportion of shrimp,crab and cephalopods in upper-middle-class resources had increased.The analysis of biodiversity showed that Margalef richress index(D),Shannon-Wiener diversity index(H) and Pielou evenness index(J) had few change.Only in spring 2010 the community seasonal changes and migration indices showed relatively big changes compared to other seasons.The abundance biomass comparison curves (ABC) indicated that the nekton community was heavily disturbed.The resource density of nekton was 435.17 kg · km-2 in weight and 67 638 ind · km-2 in number.Though the resource status had improved,the phenomenon of miniaturization and low-quality of the catch was obvious.In conclusion,the dominant species of the nekton in the Laizhou Bay changed considerably,fisheries resources continued to evolve in the direction of miniaturization and the community was disturbed seriously.The results can provide the basis information for the work and research on carrying out marine biological and ecological restoration in the Laizhou Bay.