title: Towards a framework for assessment and management of cumulative human impacts on marine food webs.
abstract: Effective ecosystem-based management requires understanding ecosystem responses to multiple human threats, rather than focusing on single threats. To understand ecosystem responses to anthropogenic threats holistically, it is necessary to know how threats affect different components within ecosystems and ultimately alter ecosystem functioning. We used a case study of a Mediterranean seagrass (Posidonia oceanica) food web and expert knowledge elicitation in an application of the initial steps of a framework for assessment of cumulative human impacts on food webs. We produced a conceptual seagrass food web model, determined the main trophic relationships, identified the main threats to the food web components, and assessed the components' vulnerability to those threats. Some threats had high (e.g., coastal infrastructure) or low impacts (e.g., agricultural runoff) on all food web components, whereas others (e.g., introduced carnivores) had very different impacts on each component. Partitioning the ecosystem into its components enabled us to identify threats previously overlooked and to reevaluate the importance of threats commonly perceived as major. By incorporating this understanding of system vulnerability with data on changes in the state of each threat (e.g., decreasing domestic pollution and increasing fishing) into a food web model, managers may be better able to estimate and predict cumulative human impacts on ecosystems and to prioritize conservation actions.
authors.affiliation: Institute of Marine Biological Resources and Inland Waters, Hellenic Centre for Marine Research, Ag. Kosmas, Greece.|ARC Centre of Excellence for Environmental Decisions, School of Biological Sciences, The University of Queensland, Brisbane, Queensland, Australia.
authors.forename: Sylvaine
authors.initials: S
authors.lastname: Giakoumi
authors.affiliation: Bren School of Environmental Science and Management, University of California, Santa Barbara, CA, 93106, U.S.A.|Imperial College London, Silwood Park Campus, Buckhurst Road, Ascot, SL57PY, United Kingdom.
authors.forename: Benjamin S
authors.initials: BS
authors.lastname: Halpern
authors.affiliation: STARESO Research Station, Revellata Cape, 20260, Calvi, France.|Oceanologie Laboratory of Oceanology, B6c Bat Chimie, University of Liege, Sart Tilman, MARE and AFFishCentres, B4000, Liege, Belgium.
authors.forename: Loïc N
authors.initials: LN
authors.lastname: Michel
authors.affiliation: Oceanologie Laboratory of Oceanology, B6c Bat Chimie, University of Liege, Sart Tilman, MARE and AFFishCentres, B4000, Liege, Belgium.
authors.forename: Sylvie
authors.initials: S
authors.lastname: Gobert
authors.affiliation: Department of Marine Sciences, University of the Aegean, University Hill, Mytilene, Lesvos Island, 81100, Greece.
authors.forename: Maria
authors.initials: M
authors.lastname: Sini
authors.affiliation: Mediterranean Institute of Oceanography (MIO), Aix-Marseille University and Toulon University, CNRS/IRD, UM 110, Campus of Luminy, 13288, Marseille Cedex 9, France.
authors.forename: Charles-François
authors.initials: CF
authors.lastname: Boudouresque
authors.affiliation: Stazione Zoologica Anton Dohrn, Napoli - Laboratory of Functional and Evolutionary Ecology, Villa Comunale, 80121, Napoli, Italy.
authors.forename: Maria-Cristina
authors.initials: MC
authors.lastname: Gambi
authors.affiliation: European Commission, Joint Research Centre, Institute for Environment and Sustainability, Ispra, Italy.
authors.forename: Stelios
authors.initials: S
authors.lastname: Katsanevakis
authors.affiliation: STARESO Research Station, Revellata Cape, 20260, Calvi, France.
authors.forename: Pierre
authors.initials: P
authors.lastname: Lejeune
authors.affiliation: DiSTAV, Department of Earth, Environment and Life Sciences, University of Genoa, Corso Europa 26, 16132, Genoa, Italy.
authors.forename: Monica
authors.initials: M
authors.lastname: Montefalcone
authors.affiliation: EqEL, FRES 3041, University of Corsica, BP 52, 20250, Corte, France.
authors.forename: Gerard
authors.initials: G
authors.lastname: Pergent
authors.affiliation: EqEL, FRES 3041, University of Corsica, BP 52, 20250, Corte, France.
authors.forename: Christine
authors.initials: C
authors.lastname: Pergent-Martini
authors.affiliation: Department of Marine Science and Applied Biology, University of Alicante, P.O. Box 99, 03080, Spain.
authors.forename: Pablo
authors.initials: P
authors.lastname: Sanchez-Jerez
authors.affiliation: Center of Pathobiochemistry and Genetics, Medical University of Vienna, Währingerstr.10/19, A-1090, Vienna, Austria.
authors.forename: Branko
authors.initials: B
authors.lastname: Velimirov
authors.affiliation: Department of Earth and Marine Sciences, University of Palermo, CoNISMa, via Archirafi 18, 90123, Palermo, Italy.
authors.forename: Salvatrice
authors.initials: S
authors.lastname: Vizzini
authors.affiliation: STARESO Research Station, Revellata Cape, 20260, Calvi, France.|Oceanologie Laboratory of Oceanology, B6c Bat Chimie, University of Liege, Sart Tilman, MARE and AFFishCentres, B4000, Liege, Belgium.
authors.forename: Arnaud
authors.initials: A
authors.lastname: Abadie
authors.affiliation: Institut de Recherche pour le Développement, UMR MARBEC (IRD, Ifremer, UM, CNRS), Avenue Jean Monnet, BP 171, 34203, Sète Cedex, France.
authors.forename: Marta
authors.initials: M
authors.lastname: Coll
authors.affiliation: Université Nice Sophia Antipolis, Faculté des Sciences, EA 4228 ECOMERS, Nice, France.
authors.forename: Paolo
authors.initials: P
authors.lastname: Guidetti
authors.affiliation: Hopkins Marine Station, Stanford University, Pacific Grove, CA, 93950, U.S.A.
authors.forename: Fiorenza
authors.initials: F
authors.lastname: Micheli
authors.affiliation: ARC Centre of Excellence for Environmental Decisions, School of Biological Sciences, The University of Queensland, Brisbane, Queensland, Australia.|Imperial College London, Silwood Park Campus, Buckhurst Road, Ascot, SL57PY, United Kingdom.
authors.forename: Hugh P
authors.initials: HP
authors.lastname: Possingham
mesh_terms: D035961:Alismatales / Q000502:physiology*; D003247:Conservation of Natural Resources / Q000379:methods*; D005398:Fisheries; D020387:Food Chain; D006801:Humans; D008522:Mediterranean Sea; D014877:Water Pollution, Chemical / Q000009:adverse effects
keywords: acciones de conservación; amenazas múltiples; conservation actions; ecosystem-based management; expert knowledge elicitation; manejo con base en los ecosistemas; multiple threats; obtención de conocimiento de expertos; pastos marinos; seagrass; vulnerabilidad; vulnerability