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Ocean stress and sustainability

GEF-UNDP/UNEP-IOC IW:LEARN and Coastal Resources Center, Graduate School of Oceanography, University of Rhode Island

By IW:LEARN

January 4^th, 2021

For most of the past half century, our oceans have been stressed by overfishing, pollution, habitat degradation, nutrient over-enrichment, biodiversity loss, and climate change. Ocean areas affected by these stressors include the world’s Large Marine Ecosystems (LMEs) which are located in the most highly productive areas of the oceans along the margins of the continents (see Figure 1). They produce 80% of the annual global marine fishery’s landings and contribute an estimated $27.7 trillion in ecosystem services each year to the global economy.

Figure 1. The world’s 66 Large Marine Ecosystems.

In support of mitigating stressors on LMEs, the Scientific Committee on Problems of the Environment (SCOPE) will release a 649 page eBook of scientific applications in January 2021. The release of this LME Megavolume coincides with the onset phase of the United Nations Decade (2021-2030) of Ocean Science in support of the Sustainable Development of the world's oceans.

The LME science-based approach to the assessment and management of coastal ocean’s goods and services was first introduced in 1984 at the annual meeting of the American Association for the Advancement of Science (AAAS). During the past 36 years, the LME approach has evolved into a global network of natural scientists, social scientists, and marine resource managers responsible for actions and results in support of sustainable development of the world's LMEs.

Results of LME studies have been published in 18 LME volumes and 390 journal articles. The LME approach is supported by scientifically derived data applied to assessing changes in LME productivity, fish and fisheries, pollution and ecosystem health, socioeconomics, and governance (see Figure 2). Analyses of data from the five modules support an ecosystems approach to LME assessment and management practices.

Figure 2. Modular Assessments for Sustainable Development.

In 1995, the Global Environment Facility (GEF), an international financial institution supporting environmental assessment and management projects for economically developing countries, included the LME approach in its operational plan. Since then, the GEF has catalyzed $3.15 billion in financial assistance to 110 economically developing countries planning and operationalizing ecosystem-based assessment and management projects in 22 of the world’s Large Marine Ecosystems (see Figure 3).

Ocean stress and sustainability

Figure 3. 110 Participating countries and 22 LMEs with GEF supported EBM projects since 1994 including: (5) Gulf of Mexico LME; (12) Caribbean Sea LME; (13) Humboldt Current LME; (14) Patagonian Shelf LME; (23) Baltic Sea; (26) Mediterranean Sea LME; (27) Canary Current LME; (28) Guinea Current LME; (29) Benguela Current LME; (30) Agulhas Current LME; (31) Somali Coastal Current LME; (32) Arabian Sea LME; (33) Red Sea LME; (34) Bay of Bengal LME; (35) Gulf of Thailand; (36) South China Sea LME; (37) Sulu-Celebes Sea LME; (38) Indonesian Sea LME; (47) East China Sea; (48) Yellow Sea LME; (53) West Bering Sea; and (62) Black Sea.

The LME eBook provides examples of science-based best practices for advancing towards the United Nations Sustainable Development Goal and Targets (SDG-14) for the oceans endorsed by the UN General Assembly in 2015 as well as the objectives expressed by the General Assembly in 2019, proclaiming 2021-2030 as the Decade of Ocean Science for Sustainable Development.

Among the cutting edge of scientific contributions is chapter 11, estimating levels of sustainable global fisheries yields. Dr. Michael Fogarty of NOAA’s Northeast Fisheries Science Center at Woods Hole and his team have developed a trophodynamic production model of total annual global marine fisheries yields. He states, “Results showed an overall fisheries production potential of 180 million tons per year and an additional 50 million tons per year for benthos {e.g. shellfish, crustaceans, and other bottom-living species} for the LMEs included in the analysis". The combined levels of fishery production estimates of 230 million tons per year is quite robust, suggesting relatively high fishery production levels over the coming years. The authors state “If these potential yields are to be realized, an overall diversification of the complex of harvested species will have to be achieved together with a reduction of the rates of exploitation of overfished species. It is clear that the best prospect for potential increase in fish yield is for planktivorous {plankton feeding} species. If this expansion is to occur it must be undertaken with consideration of the forage needs of other species in the system. It must also be recognized that many of the species that can potentially support such an increase{in annual yield} will be processed for fish meal and oils and not used for direct human consumption. Such species can contribute to an expansion of mariculture for upper trophic food species and as food supplies for farm animals.”

With regard to pollution of LMEs, the chapter by Dr. Rosalyn Lee of the University of Southern California and associates assesses the level of land-based nutrient input to the world’s LMEs. The excess of nutrient loadings from river systems into LMEs carry high levels of dissolved inorganic nitrogen (DIN) from fertilizers and other farm-based production activities (see Figure 4). These excessive nutrient loadings frequently result in oxygen depletion events, disrupting normal production cycles in coastal waters of LMEs, leading to dead zones and mortality of marine resources. The authors conclude, if current trends continue, DIN input will increase by approximately 40-45% in LMEs along the coast of South America, Southeast Asia, and Europe by 2050.

Figure 4. DIN load to LMEs. Watersheds discharging to LMEs are grey; watersheds with zero coastal discharge are white.

The global network of LME project practitioners is making good progress towards reaching UN ocean sustainability targets. In Africa, the progress is most advanced in the GEF-supported Benguela Current Large Marine Ecosystem (BCLME) project, based on positive actions supported by ecosystem-based data and analysis on productivity, fish and fisheries, pollution and ecosystem health, socioeconomics, and governance. The collaborating countries sharing the goods and services of BCLME, namely Angola, Namibia, and South Africa, established the world's first commission for implementing sustainable development of the major economic sectors of the ecosystem including fisheries, energy, transportation, tourism, and mining (see Figure 5). Since the mid-1990s, the project has received funding assistance for several five-year phases of implementation, leading to improved ecological and socioeconomic conditions as described in chapter 33.

Figure 5

In Asia, the People's Republic of China and the Republic of Korea have for over 15 years participated in planning and implementing a GEF-supported ecosystem-based approach for the sustainable development of the Yellow Sea LME (YSLME) (see Figure 6). Both countries are engaged in a five-year implementation phase for establishing a joint commission to oversee efforts for sustainable development of the goods and services of the YSLME as described in chapter 30 titled “Sustainable Development of The Yellow Sea Large Marine Ecosystem.”

The pragmatic utility of spatial planning in LMEs is illustrated in chapter 39, by Dr. Sandra Whitehouse, Senior Advisor to the Ocean Conservancy, who describes the spatial planning approach leading to the placement of the first offshore array of US wind-driven turbines for producing energy in a heavily fished area of the Northeast Shelf Large Marine Ecosystem.

The definitive LME volume, which is financed by GEF-UNDP/IOC/UNESCO IW:LEARN, is being released by SCOPE on the eve of the Oceans Science Decade, to inform the marine science and resource management communities of the actions and results that are pertinent to the United Nations policies for advancing progress in achieving the UN sustainable oceans goal by 2030.

Fill out this form to register and be able to download a copy of the LME Definitive Volume - "Ocean Sustainability: Assessing and Managing the World’s Large Marine Ecosystems."

For more information on the publication, please contact Dr. Kenneth Sherman (kensherman@etal.uri.edu).

To know more about the GEF LME community, please visit the GEF LME:LEARN/IW:LEARN Marine Hub.

Ocean stress and sustainability

Footnotes

Cover photo by Jakob Owens on Unsplash.

FootNotes

Cover photo by Jakob Owens on Unsplash.

© 2026 IW:LEARN

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