Acquiring a comprehensive and accurate understanding of habitat preference is essential for species conservation and fishery management,especially for mobile species that migrate seasonally.Presence and absence data f...Acquiring a comprehensive and accurate understanding of habitat preference is essential for species conservation and fishery management,especially for mobile species that migrate seasonally.Presence and absence data from field surveys are recommended when available due to their high reliability.Using field survey data,we investigated seasonal habitat suitability requirements for Tanaka's snailfish(Liparis tanakae)in the Bohai Sea and Yellow Sea(BSYS)via a machine-learning method,random forests(RFs).Five environmental and biologically relevant variables(bottom temperature,bottom salinity,current velocity,depth and distance to shore)were used to build the ecological niches between the presence/absence data and suitable habitat.In addition,the degree to which false absence data might impact model performance was evaluated.Our results indicated that RFs provided accurate predictions,with seasonal habitat suitability maps of L.tanakae differing substantially.Bottom temperature and salinity were identified as important factors influencing the distribution of L.tanakae.False absence data were found to have negative effects on model performance and the decrease in evaluation metrics was usually significant(P<0.05)after 30%or more errors were added to the absence data.Through identifying highly suitable areas within its geographic range,our study provides a baseline for L.tanakae that can be further applied in ecosystem modelling and fishery management in the BSYS.展开更多
本研究基于2016年对南海三省区的14个沿海主要渔港的连续4个季节抽样调查(共计5256航次,抽样总功率达到89.2×10^4 kW),以kg·kW^-1·d^-1作为CPUE(Catch per unit effort,单位捕捞努力量渔获量)标准化后的单位,对南海9种...本研究基于2016年对南海三省区的14个沿海主要渔港的连续4个季节抽样调查(共计5256航次,抽样总功率达到89.2×10^4 kW),以kg·kW^-1·d^-1作为CPUE(Catch per unit effort,单位捕捞努力量渔获量)标准化后的单位,对南海9种捕捞作业类型渔船的CPUE进行了比较分析。结果显示,CPUE围网>CPUE双拖>CPUE刺网>CPUE罩网>CPUE张网>CPUE单拖>CPUE虾拖>CPUE笼壶>CPUE钓具。不同捕捞作业类型CPUE随渔船功率段的变化而不同,CPUE峰值数及其所对应的最优功率段(渔获率最高的功率段)也有差异,单拖和虾拖渔船的CPUE随渔船功率的变化具有1个CPUE峰值点,最优功率段分别为(200~250)kW(CPUE=8.6 kg·kW^-1·d^-1)和(150~200)kW(CPUE=5.0 kg·kW^-1·d^-1);围网、双拖、钓具和刺网渔船的CPUE随渔船功率的变化有2个CPUE峰值点,对应的最优功率段分别为(200~250)kW(CPUE=47.7 kg·kW^-1·d^-1)、(350~400)kW(CPUE=16.8kg·kW^-1·d^-1)、(50~100)(CPUE=2.9kg·kW^-1·d^-1)和(0~50)kW(CPUE=6.9 kg·kW^-1·d^-1)。罩网渔船CPUE随功率段变化有3个峰值点,最优功率段为(0~50)kW(CPUE=7.0kg·kW^-1·d^-1)。不同捕捞作业类型CPUE季节变化表现:围网CPUE均值在春季最高,单拖、双拖、罩网、钓具和笼壶在夏季最高,张网在秋季最高,刺网和虾拖在冬季最高。展开更多
基金The National Natural Science Foundation of China under contract No.42176151the Youth Talent Program Supported by Laboratory for Marine Fisheries Science and Food Production Processes,Pilot National Laboratory for Marine Science and Technology(Qingdao)under contract No.2018-MFS-T05the Central Public-Interest Scientific Institution Basal Research Fund,Yellow Sea Fisheries Research Institute,Chinese Academy of Fishery Sciences under contract Nos 20603022019010 and 20603022022022。
文摘Acquiring a comprehensive and accurate understanding of habitat preference is essential for species conservation and fishery management,especially for mobile species that migrate seasonally.Presence and absence data from field surveys are recommended when available due to their high reliability.Using field survey data,we investigated seasonal habitat suitability requirements for Tanaka's snailfish(Liparis tanakae)in the Bohai Sea and Yellow Sea(BSYS)via a machine-learning method,random forests(RFs).Five environmental and biologically relevant variables(bottom temperature,bottom salinity,current velocity,depth and distance to shore)were used to build the ecological niches between the presence/absence data and suitable habitat.In addition,the degree to which false absence data might impact model performance was evaluated.Our results indicated that RFs provided accurate predictions,with seasonal habitat suitability maps of L.tanakae differing substantially.Bottom temperature and salinity were identified as important factors influencing the distribution of L.tanakae.False absence data were found to have negative effects on model performance and the decrease in evaluation metrics was usually significant(P<0.05)after 30%or more errors were added to the absence data.Through identifying highly suitable areas within its geographic range,our study provides a baseline for L.tanakae that can be further applied in ecosystem modelling and fishery management in the BSYS.
文摘本研究基于2016年对南海三省区的14个沿海主要渔港的连续4个季节抽样调查(共计5256航次,抽样总功率达到89.2×10^4 kW),以kg·kW^-1·d^-1作为CPUE(Catch per unit effort,单位捕捞努力量渔获量)标准化后的单位,对南海9种捕捞作业类型渔船的CPUE进行了比较分析。结果显示,CPUE围网>CPUE双拖>CPUE刺网>CPUE罩网>CPUE张网>CPUE单拖>CPUE虾拖>CPUE笼壶>CPUE钓具。不同捕捞作业类型CPUE随渔船功率段的变化而不同,CPUE峰值数及其所对应的最优功率段(渔获率最高的功率段)也有差异,单拖和虾拖渔船的CPUE随渔船功率的变化具有1个CPUE峰值点,最优功率段分别为(200~250)kW(CPUE=8.6 kg·kW^-1·d^-1)和(150~200)kW(CPUE=5.0 kg·kW^-1·d^-1);围网、双拖、钓具和刺网渔船的CPUE随渔船功率的变化有2个CPUE峰值点,对应的最优功率段分别为(200~250)kW(CPUE=47.7 kg·kW^-1·d^-1)、(350~400)kW(CPUE=16.8kg·kW^-1·d^-1)、(50~100)(CPUE=2.9kg·kW^-1·d^-1)和(0~50)kW(CPUE=6.9 kg·kW^-1·d^-1)。罩网渔船CPUE随功率段变化有3个峰值点,最优功率段为(0~50)kW(CPUE=7.0kg·kW^-1·d^-1)。不同捕捞作业类型CPUE季节变化表现:围网CPUE均值在春季最高,单拖、双拖、罩网、钓具和笼壶在夏季最高,张网在秋季最高,刺网和虾拖在冬季最高。
