南海柘林湾鱼类群落结构季节变动的研究

为阐明南海柘林湾鱼类群落结构的动态变化,基于2011年4月(春季)、8月(夏季)、11月(秋季)和2012年2月(冬季)对南海柘林湾拖网调查的数据,对柘林湾鱼类群落结构季节动态、鱼类营养级指数季节变化进行了初步分析。结果显示,各季节调查共捕获鱼类99种,底层鱼类占49.49%,暖水性鱼类占78.78%,肉食性鱼类占79.79%。各季节质量百分比和数量百分比优势种以拟矛尾■虎鱼(Parachaeturichthys polynema)、龙头鱼(Harpodon nehereus)、皮氏叫姑鱼(Johnius belengeri)等为主。柘林湾鱼类资源密度和资源尾数密度最高季节为夏季,各季节鱼类个体体质量大多小于15 g。春、秋季鱼类组成相对丰富,冬季生物量优势度最高。柘林湾鱼类以中级肉食性和高级肉食性为主,年度平均营养级指数为3.478,属于中级水平,夏季高营养级鱼类平均体质量最高。

Seasonal variation of fish community structure in Zhelin Bay,the South China Sea

Based on the date collected by quarterly otter trawl surveys in Zhelin Bay from 2011 to 2012,we analyzed the fish species composition,resources structure and trophic level.A total of 99 fishes were collected during the surveys.The proportions of demersal fish,tropical fish,and carnivorous fish were 49.49%,78.78% and 79.79%,respectively.The composition of the dominant species of biomass and abundance percentages was similar,including Parachaeturichthys polynema,Harpodon nehereus and Johnius belengeri.The maximal biomass and abundance of fish were in summer in Zhelin Bay.The average body weight of fish in four seasons was less than 15 g.The composition of fish was more abundant in spring and autumn.The dominance of biomass of fish was the highest in winter.The feeding habit of fish in Zhelin Bay was mainly intermediate carnivorous and advanced carnivorous.The change of trophic level of four seasons was inconspicuously.The annual average trophic level index was 3.478 of intermediate level.It was in summer that the average body weight of high trophic level fish peaked.