THE GULF OF MEXICO ECOSYSTEM: A COASTAL AND MARINE ATLAS
Consortium was the original source of data on the extent of the Louisiana-Texas dead zone in Map 43 (Rabalais et al., 2011). However, Map 43 is based on representations of the annual hypoxia footprint maps from 1985 through 2001 compiled by the Gulf States Marine Fisheries Commission. These annual hypoxia extents were combined to show the cumulative annual extent of areas that experienced hypoxia at any point during that 15-year period. Diaz et al. (2011) was the source of data for isolated dead zones along the remainder of the Gulf Coast. Data Quality Data quality for Map 43 is fair, primarily because the mid-summer hypoxia cruise data for oxygen concentrations in the north-central Gulf were derived from map representations and not directly from the original data. The rating is also lower because oxygen concentration monitoring is infrequent in most areas of the U.S. Gulf, and many sites that experience low oxygen may be missed by the sampling
programs. One location of hypoxia is documented in Mexico but no comprehensive data were identified for Mexico and Cuba. Synthesis and Conclusions The Gulf dead zone is of particular concern to Gulf ecosystem services, such as valuable commercial and recreational Gulf fisheries. The EPA Science Advisory Board (2007) recommends a significant reduction of nutrients. Targeted nutrient reduction measures have been identified as a viable hypoxia abatement strategy (Graham et al., 2011; EPA, 2008). Continued support is needed for studies that evaluate and monitor the causes of hypoxia and investigate this stressor’s effects on living resources and coastal economies. Studies are also needed to better understand the cumulative effects of multiple stressors, such as climate change, hypoxia and the BP Deepwater Horizon oil disaster on the Gulf marine ecosystem.
Text Citations Committee on Environment and Natural Resources. (2010). Scientific assessment of hypoxia in U.S. coastal waters. Interagency Working Group on Harmful Algal Blooms, Hypoxia, and Human Health of the Joint Subcommittee on Ocean Science and Technology. Washington, DC. Conley, D. J., Carstensen, J., Aigars, J., Axe, P., Bonsdorff, E., Eremina, T., Haahti, B.-M., Humborg, C., Jonsson, P., Kotta, J., Lännegren, C., Larsson, U., Maximov, A., Rodriguez Medina, M., Lysiak-Pastuszak, E., Remeikaitė-Nikienė, N., Walve, J., Wilhelms, S., & Zillén, L. (2011). Hypoxia is increasing in the coastal zone of the Baltic Sea. Environmental Science and Technology, 45, 2777-2783. Diaz, R. J., & Rosenberg, R. (2008). Spreading dead zones and consequences for marine ecosystems. Science, 321, 926-929. Graham, B., Reilly, W. K., Beinecke, F., Boesch, D. F., Garcia, T. D., Murray C. A., & Ulmer, F. (2011). Deep water: The Gulf oil disaster and the future of offshore drilling. National Commission on the BP Deepwater Horizon Oil Spill and Offshore Drilling. Levin, L.A. (2003). Oxygen minimum zone benthos: Adaptation and community response to hypoxia. Oceanography and Marine Biology: an Annual Review, 41, 1- 45. Louisiana Universities Marine Consortium (LUMCON). (2010). 2010 dead zone – one of the largest ever. Retrieved from http://www.gulfhypoxia.net/Research/Shelfwide%20Cruises/2010/PressRelease2010.pdf
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