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根据2012年1—4月在长江口东旺沙、佘山岛、青草沙、东风西沙、九段沙和南汇水域8个采样点的调查数据,研究了长江口日本鳗鲡鳗苗的时空分布特征。结果表明:2012年长江口鳗苗主汛期为2—3月,苗汛高峰时间呈现由南向北、由口外向内逐渐推迟的趋势,与其洄游路线一致;鳗苗主要分布区为长江口外的南汇、佘山岛、东旺沙水域,其中南汇水域产量最高,长江口内的青草沙、东风西沙水域产量较低;通过定点监测与问卷调查估算,2012年长江口鳗苗产量约1680万尾,产值5亿元左右;为实现长江口鳗苗资源的可持续利用,建议将捕捞期调整至2—3月,捕捞区域限制在南汇—佘山岛的长江口外水域。
According to the survey data of 8 sampling sites in Dongwangsha, Sheshan Island, Qingcaosha, Dongfeng Xisha, Jiuduansha and Nanhui waters in the Yangtze Estuary from January to April, 2012, the spatial and temporal distribution characteristics of Japanese eel eel (Anguilla japonica) were studied. The results showed that the main flood season of the eel fry in the Yangtze River estuary was from February to March in 2012, and the peak frosty season appeared from south to north, which gradually degenerated from the outside to the outside, consistent with the migratory routes; Nanhui, Sheshan Island and Dongwangsha waters. Among them, Nanhui had the highest yield in the waters. The production of Qingcaosha and Dongfeng Xisha in the Changjiang Estuary was relatively low. According to the fixed-point monitoring and questionnaire survey, the output of the eel in the Yangtze River estuary in 2012 was 16.8 million, 500 million yuan. In order to realize the sustainable utilization of resources of the eel fry in the mouth of the Yangtze River, it is suggested that the fishing season should be adjusted from February to March and the fishing area should be limited to the waters outside the Yangtze River in Nanhui-Sheshan Island.