水产学报2017，Vol.41Issue(4)：547-555,9.DOI:10.11964/jfc.20160510419
长江近口段鳗苗捕捞量的时间格局及其与生态因子的GAM模型分析
Temporal pattern of Anguilla japonica glass eels catches at Jingjiang section of the Yangtze River in fishing season in relation to ecological factors using a generalized additive model (GAM)
摘要
Abstract
To analyze daily variations in Anguilla japonica glass eel catch as related to ecological factors at Jingjiang section of the Yangtze River,we conducted daily monitoring program at Jingjiang section of the Yangtze River during the 2012 fishing season.A generalized additive model (GAM) was applied to evaluate the relationships between daily catch and their ecological variables,including water temperature,the tidal range,turbidity,lunar phase,tide phase and pressure.Fishing was performed at Jingjiang section of the Yangtze River from late January to early April.The total fishing period catch per boat ranged from 221 ind.to 443 ind.with a mean±SD of (344.8±83.4) ind.The daily catch differed by month.The mean daily catch was only 0.4 ind./d in January,and the abortive haul rate was 90.9％;while mean daily catch was up to 10.4 ind./d in April,and the abortive haul rate was only 10.0％.Stepwise GAM building using the AIC and adjusted pseudo-R2 showed that turbidity,pressure and lunar phase did not affect daily catch of A.japonica glass eels significantly,but three predictor variables,tide phase-month interaction,water temperature and tidal range were highly significant.In addition,tide phase-month interaction,water temperature,and tidal range account for 42.4％,19.1％ and 13.1％ of the variance in the data,respectively,and these three variables also showed a positive relationship with the daily catch.Statistical results also showed that the daily catch fluctuated with tide phase,since high catches appeared at times corresponding to the spring tide of the full moon or the new moon,while,low catches appeared at times corresponding to the neap tide during quarter moons.Moreover,glass eels were caught when the minimum water temperature was 6.3 ℃,and a greater catch was found in optimal water temperature ranging between 10 and 15 ℃.Overall,the proportion of total catches for spring or neap tide period was 76.8％ and 23.2％,respectively.Furthermore,our results suggested that during glass eels upstream migration using'selective tidal stream transport',some individuals were captured in the mouth zone of the Yangtze estuary,and some individuals preferred to stay near the river section of the estuary,whereas others migrated upstream.In our study,water temperature,tidal range and tide phase were the important ecological factors affecting the fluctuations in upstream migration of glass eels.关键词
日本鳗鲡/生态因子/渔汛期/广义可加模型/长江口Key words
Anguilla japonica/ecological factors/fishing season/generalized addititve model/Yangtze River estuary分类
农业科技引用本文复制引用
郭弘艺,张旭光,唐文乔,张亚,吴嘉敏,沈林宏..长江近口段鳗苗捕捞量的时间格局及其与生态因子的GAM模型分析[J].水产学报,2017,41(4):547-555,9.基金项目
公益性行业(农业)科研专项(201203065) （农业）
上海市农委科技兴农重点攻关项目(沪农科攻字2013第2-2号) （沪农科攻字2013第2-2号）
国家自然科学基金(31472280)Special Fund for Agro-Scientific Research in the Public Interest (201203065) （31472280）
Key Project of Science and Technology of Shanghai Municipal Agricultural Commission(2013-2-2) （2013-2-2）
National Natural Science Foundation of China (31472280) （31472280）
