An evaluation of underlying mechanisms for“fishing down marine food webs”  

作　　者：DING Qi CHEN Xinjun YU Wei TIAN Siquan CHEN Yong 

机构地区：[1]College of Marine Sciences,Shanghai Ocean University,Shanghai 201306,China [2]Key Laboratory of Sustainable Exploitation of Oceanic Fisheries Resources of Ministry of Education,Shanghai Ocean University,Shanghai 201306,China [3]National Engineering Research Center for Oceanic Fisheries,Shanghai Ocean University,Shanghai 201306,China [4]Collaborative Innovation Center for Distant-water Fisheries,Shanghai 201306,China [5]School of Marine Sciences,University of Maine,Orono,Maine 04469,USA

出　　处：《Acta Oceanologica Sinica》2016年第8期32-38,共7页海洋学报（英文版）

基　　金：The National Natural Science Foundation of China under contract Nos NSFC41306127 and NSFC41276156;the Funding Program for Outstanding Dissertations in Shanghai Ocean University;the Funding Scheme for Training Young Teachers in Shanghai Colleges and Shanghai Leading Academic Discipline Project(Fisheries Discipline);the involvement of Y.Chen was supported by SHOU International Center for Marine Studies and Shanghai 1000 Talent Program

摘　　要：Since the concept of ＂fishing down marine food webs＂ was first proposed in 1998, mean trophic level of fisheries landings（MTL） has become one of the most widely used indicators to assess the impacts of fishing on the integrity of marine ecosystem and guide the policy development by many management agencies. Recent studies suggest that understanding underlying causes for changes in MTL is vital for an appropriate use of MTL as an indicator of fishery sustainability. Based on the landing data compiled by Food and Agriculture Organization（FAO） and trophic information of relevant species in Fishbase, we evaluated MTL trends in 14 FAO fishing areas and analyzed catches of upper and lower trophic level groups under different trends of MTL and found that both the cases of a recovered MTL trend and a generally increasing MTL trend could be accompanied by decreasing catches of lower trophic level species. Further, community structure and exploitation history should be considered in using MTL after excluding species with trophic levels lower than 3.25 to distinguish ＂fishingthrough＂ from ＂fishing-down＂. We conclude that MTL used as an indicator to measure fishery sustainability can benefit from a full consideration of both upper and lower trophic level species and masking effects of community structure and exploitation history.Since the concept of ＂fishing down marine food webs＂ was first proposed in 1998, mean trophic level of fisheries landings（MTL） has become one of the most widely used indicators to assess the impacts of fishing on the integrity of marine ecosystem and guide the policy development by many management agencies. Recent studies suggest that understanding underlying causes for changes in MTL is vital for an appropriate use of MTL as an indicator of fishery sustainability. Based on the landing data compiled by Food and Agriculture Organization（FAO） and trophic information of relevant species in Fishbase, we evaluated MTL trends in 14 FAO fishing areas and analyzed catches of upper and lower trophic level groups under different trends of MTL and found that both the cases of a recovered MTL trend and a generally increasing MTL trend could be accompanied by decreasing catches of lower trophic level species. Further, community structure and exploitation history should be considered in using MTL after excluding species with trophic levels lower than 3.25 to distinguish ＂fishingthrough＂ from ＂fishing-down＂. We conclude that MTL used as an indicator to measure fishery sustainability can benefit from a full consideration of both upper and lower trophic level species and masking effects of community structure and exploitation history.

关 键 词：mean trophic level underlying mechanisms community structure and exploitation history fishery landings 

分 类 号：S97[农业科学—捕捞与储运]