基于遥感数据的大亚湾伏季休渔效果评价

Effect assessment of summer fishing moratorium in Daya Bay based on remote sensing data

为定量评估大亚湾伏季休渔的养护效果,以渔业环境卫星遥感和拖网调查相结合的方法,对大亚湾休渔前(2015年5月)和休渔后(2015年8月)海表温度和叶绿素a浓度、总渔获物的单位捕捞努力量渔获量(catch per unit effort,CPUE)、生物多样性、种类组成和体长、体质量变动进行了对比分析。结果表明,伏季休渔后,总渔获物CPUE的主要分布范围从休渔前的0~10 kg·h–1提高到休渔后的0~40 kg·h–1。渔获物平均体长和体质量增加,生长速率加快。渔业资源Shannon-Wiener多样性指数(H')和Pielou均匀度指数(J')分别增加了0.36和0.14,群落结构有所改善。渔业资源群落的生物量谱研究表明,休渔后标准化生物量谱线性回归系数大于–1,生物量随个体体质量的增加而增加。伏季休渔降低了近海的捕捞强度,恢复和养护了大亚湾的渔业资源。建议采取适当延长休渔期、减控近海渔船数、加强资源养护等措施,进一步完善休渔制度,促进近海渔业资源的可持续发展。

Based on the data of satellite remote sensing and trawl surveys,we analyzed the variation in sea surface temperature（SST）,chlorophyll a（Chl-a）concentration,catch per unit effort（CPUE）of total catch,biodiversity,species composition,body length and mass of total catch during the pre-SFM（May in 2015）and post-SFM（August in 2015）in Daya Bay,to assess the maintenance effect of summer fishing moratorium（SFM）in that area.Results show that the major variation range of CPUE increased from 0-10kg·h^（–1） in the pre-SFM to 0-40 kg·h^（–1） in the post-SFM.The average body length and mass increased,indicating that the growth rate of total catch accelerated.In the post-SFM,the indices of Shannon-Wiener and Pielou increased by 0.36 and 0.14,respectively,which shows that the community structure was improved.The biomass spectra of the fishery resource community shows that the slopes of normalized biomass spectra in the post-SFM was over–1,and the biomass of fishery resources increased with the increase of the individual body mass in the post-SFM.SFM alleviated the fishing intensity,recovered and conserved the fishery resources in Daya Bay.In order to improve the SFM system and promote sustainable development of coastal fishery resources,it is suggested to prolong the time of SFM appropriately,reduce the number of coastal fishing boats,and enforce the conservation of fish resources.