Biogeosciences www.biogeosciences.net 1726-4170 1726-4189 7 5 2010 10.5194/bg-7-1443-2010 http://www.biogeosciences.net/7/1443/2010/ http://www.biogeosciences.net/7/1443/2010/bg-7-1443-2010.html http://www.biogeosciences.net/7/1443/2010/bg-7-1443-2010.pdf 1443 1467 2010-05-10 Natural and human-induced hypoxia and consequences for coastal areas: synthesis and future development J. Zhang jzhang@sklec.ecnu.edu.cn D. Gilbert A. J. Gooday L. Levin S. W. A. Naqvi J. J. Middelburg M. Scranton W. Ekau A. Peña B. Dewitte T. Oguz P. M. S. Monteiro E. Urban N. N. Rabalais V. Ittekkot W. M. Kemp O. Ulloa R. Elmgren E. Escobar-Briones A. K. Van der Plas State Key Laboratory of Estuarine and Coastal Research, East China Normal University, 3663 Zhongshan Road North, Shanghai 200062, China Maurice-Lamontagne Institute, Fisheries and Oceans Canada, Mont-Joli, Quebec G5H 3Z4, Canada National Oceanography Centre, Southampton, Empress Dock, European Way, Southampton SO14 3ZH, UK Integrative Oceanography Division, Scripps Institution of Oceanography, 9500 Gilman Dr., La Jolla, CA 92093-0218, USA Chemical Oceanography Division, National Institute of Oceanography, Dona Paula, Goa 403004, India Netherlands Institute of Ecology, Centre for Estuarine and Marine Ecology, Korringaweg 7, 4401 NT Yerseke, and Faculty of Geosciences, Utrecht University, P.O. Box 80021, 3508 TA Utrecht, The Netherlands School of Marine and Atmospheric Sciences, Stony Brook University, Stony Brook NY 11794, USA Center for Tropical Marine Ecology, Fahrenheitstrasse 6, 28359 Bremen, Germany Institute of Ocean Sciences, Fisheries & Oceans Canada, P.O. Box 6000, Sidney, B.C. V8L 4B2, Canada LEGOS/IRD, 14 av. Edouard Belin, 31400 Toulouse, France Institute of Marine Sciences, Middle East Technical University, Erdemli 33731, Turkey Ocean Systems & Climate Group, CSIR, P.O. Box 320, Stellenbosch 7599, South Africa Scientific Committee on Oceanic Research, College of Earth, Ocean, and Environment, University of Delaware, Newark, DE 19716, USA Louisiana Universities Marine Consortium, 8124 Highway 56, Chauvin, LA 70344, USA Horn Point Laboratory, University of Maryland Center for Environmental Science, P.O. Box 775, Cambridge, MD 21613, USA Departmento de Oceanografia, Universidad de Concepcion, Cabina 7 – Barrio Universitario, Casilla 160-C, Concepcion 3, Chile Department of Systems Ecology, Stockholm University, 10691 Stockholm, Sweden Instituto de Ciencias del Mar y Limnologia, Universidad National Autonoma de Mexico, A. P. 70305 Ciudad Universitaria 04510, Mexico Ministry of Fisheries and Marine Resources, P.O. Box 912, Swakopmund, Namibia Hypoxia has become a world-wide phenomenon in the global coastal ocean and causes a deterioration of the structure and function of ecosystems. Based on the collective contributions of members of SCOR Working Group #128, the present study provides an overview of the major aspects of coastal hypoxia in different biogeochemical provinces, including estuaries, coastal waters, upwelling areas, fjords and semi-enclosed basins, with various external forcings, ecosystem responses, feedbacks and potential impact on the sustainability of the fishery and economics. The obvious external forcings include freshwater runoff and other factors contributing to stratification, organic matter and nutrient loadings, as well as exchange between coastal and open ocean water masses. Their different interactions set up mechanisms that drive the system towards hypoxia. Coastal systems also vary in their relative susceptibility to hypoxia depending on their physical and geographic settings. It is understood that coastal hypoxia has a profound impact on the sustainability of ecosystems, which can be seen, for example, by the change in the food-web structure and system function; other influences include compression and loss of habitat, as well as changes in organism life cycles and reproduction. In most cases, the ecosystem responds to the low dissolved oxygen in non-linear ways with pronounced feedbacks to other compartments of the Earth System, including those that affect human society. Our knowledge and previous experiences illustrate that there is a need to develop new observational tools and models to support integrated research of biogeochemical dynamics and ecosystem behavior that will improve confidence in remediation management strategies for coastal hypoxia. Aller, R. 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