渤海越冬场渔业生物资源量和群落结构的动态特征

根据1983、1993和1999年冬季在渤海越冬场拖网试捕采集的渔获量资料,分析研究了渤海渔业生物地方种群的种类组成、生物量指数和优势种群的年间变化。资源量呈逐年大幅度减少之势,平均网获量分别为115kg/h、35kg/h和07kg/h,平均网获尾数则为669尾/h、145尾/h和37尾/h;群落结构和优势种发生了明显的变化,1983～1993年的优势种群梅童和孔鳐等经济底层鱼类为安氏新银鱼所替代。捕捞过度是经济种群资源量剧减的主要原因,强化渔政管理,开展经济种群的种苗放流是保护、恢复和增殖渔业资源的主要措施和途径。

Dynamic characteristics of abundance and community structure of fishery species in the overwintering ground of the Bohai Sea

By the bottom trawl surveys in the overwintering ground of the Bohai Sea in the winter of 1983,1993 and 1999,the yearly variations of species composition,abundance index and dominant species of endemic stocks were analyzed The abundance trended to decrease dramatically,the average catch per haul was 11 5,3 5 and 0 7 kg/h,and average number of individuals per haul was 669,145 and 37 individual/h,respectively The community structure and dominant species obviously changed Those dominant species like Collichthys spp.and Raja porosa in 1983～ 1993 were replaced by Neosalanx anderssoni in 1999 Overfishing is the main cause for the sharp decrease of abundance in economic important species Strengthening fishery management,and implementing hatchery release are the main measures and approaches to conserving,rehabilitating and enhancing fishery resources in the Bohai Sea