中越北部湾共同渔区秋季渔获鱼类多样性

Survey of Fisheries Resources and Biodiversity in China-Vietnam Collective Fishery Zone in Autumn by a Bottom Trawl

根据2015年秋季中越北部湾共同渔区底拖网调查资料,统计调查海域的物种组成和优势种鱼类情况,同时从质量和尾数两方面分析该海域的生物多样性,并结合ABC曲线初步探讨该海域生物群落稳定性受环境干扰程度。调查结果表明,本次调查共发现103种鱼,隶属于16目51科,其中以鲈形目最为丰富,占总鱼类渔获质量的95.44%;该海域的优势种(相对重要性指数≥500)鱼类有鲐鱼(相对重要性指数为16 093.70)和二长棘鲷(相对重要性指数为715.68)2种;与已有的文献相比,本次调查海域中物种多样性指数、丰富度指数以及均匀度指数均偏低;物种多样性指数显示,16个站位(占总站位数57.1%)属于重度污染区(物种多样性指数<1),这可能与捕捞压力、环境干扰、水温变化以及调查区域范围小等因素有关;ABC曲线中质量曲线和尾数曲线出现交叉,W=0.002,该海域受中等程度的干扰。

The species composition,dominant species and biodiversity of fisheries resources in Common Fishery Zone between China and Vietnam were surveyed in autumn of 2015,and stability of fish community in the zone was assessed using abundance-biomass comparison(ABC)analysis to monitor the degree of environmental disturbance.A total of 103 species of fish belonging to 16 orders and 51 families were recorded in the survey,with the most abundant in Perciformes in volume,accounting for 9 5%of the total catch.Both.Pneumatophorus japonicus(IR I=1 6 094.70)and Paerargyrops edita(IR I=715.68)were considered as the dominant species in the zone,with index of relative importance(IRI)over or equal to 500.Shannon-Wiener index(H’),Margalef's index(D)and Pielou's evenness index(J’)in the zone were found to be relatively lower in present survey compared to previous data.The Shannon-Wiener index revealed that 16 stations(57.1%of the sampling stations)were found as heavily polluted area(H'<1),which is involved in the catch pressure,environmental disturbances,water temperature fluctuations and limited sampling area.The intersection between biomass and abundance curves as well as the W value(0.002)indicated that the gulf was moderately polluted.