Sustaining the World's Large Marine Ecosystems

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estimated at 30 years. These features are major factors that increase the susceptibility of the Baltic Sea to accumulate pollutants. 64 Figure 1. The Baltic Sea LME catchment area (outlined in dark red). The Baltic Sea comprises three deep basins separated by shallow sills: the Arkona Deep, at the entrance to the Baltic Sea, the Bornholm Deep, and the Gotland Deep, farthest inwards. Saltier, heavier and oxygen-rich water from the North Sea enters the Baltic Sea through the shallow, narrow entrance and propagates along the deeper regions, while a counter current of freshwater flows outwards at the surface. This results, throughout most of the ecosystem, in two vertically stratified parts of the water column, which rarely mix. This stratification significantly limits the passage of oxygen from the surface into the deeper waters. The inflows of oxygen-rich water are of vital importance for the well-being and
productivity of the biota and determine the environmental quality of the Baltic Sea LME. Unfortunately, these inflows causing flushing of the Baltic Sea are unpredictable and infrequent, with periods of stagnation between flushing events that last as long as several decades, such that oxygen levels decline over time between each inflow due to the biological oxygen demands of living organisms and the breakdown of organic material. Although the influxes are basically random and connected with climatic variability that is not due to human influences, it appears that these influxes since the second half of the 20 th century are decreasing in both frequency and magnitude. Because of its history and brackish environment, the Baltic Sea LME is characterized by the low number and biodiversity of plant and animal species than in more saline waters. The brackish water is too salty for most freshwater species and too fresh for most marine species. For example, the number of macroscopic and microscopic animal species west of Sweden is roughly 1,500; in the southern Baltic there are only about 150 species, and in the water around Gotland only about 80 species. The same applies to fish: the Kattegat has around 100 marine fish species, while the Sound has only 55 and the Archipelago Sea only about 20. Other fish species are representative of those normally found in freshwater lakes and rivers all over the region, so that a single catch in the Bothnian Bay might consist of a unique combination of cod, herring, perch, and pike. The salinity gradient is paralleled by a climatic gradient with up to six months of ice cover, a productive season of 4-5 months in the northern Gulf of Bothnia, and an 8-9 month productive season in the southern sounds near its entrance. Besides these variations in biodiversity, it is typical that the few species penetrating into brackish waters are typically slower growing and of smaller size than in their original habitats, irrespective of whether their original habitats are marine or freshwater. Thus, the Baltic Sea environment and its biological diversity are unique. Its associated biota is facing a special challenge in living under a difficult natural environment that is particularly vulnerable to pollution and other human-caused stresses. Despite the limited number of species, the structure and functioning of the BSLME is not simple. Typically, energy flows in shorter or longer food chains of up to a maximum of about five trophic levels, from the primary production originating from plants living in the sea and coastal areas, via grazing by herbivorous animals (e.g. zooplankton), and successive levels of predation to the higher level predators such as fish, seabirds and shorebirds, and marine mammals. Besides this typical ‘grazing’ food chain, we also have a microbial food chain that is longer and accordingly less efficient but no less important. The whole picture is complicated by important multispecies interactions, e.g. predatorprey relationships, interlinking the various food chains into a food web. The abundance of species and the structure and function of the food webs and ecosystems vary as a result of changing environmental conditions and human impacts. 65
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Sustaining the World’s Large Mari
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Preface This volume, Sustaining the
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describing practical applications o
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Contents Preface iii Contents vii G
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GEF Support for the Global Movement
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ozone depletion, and international
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These processes are critical for in
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(BCLME) project serves as a success
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Ultimately, each nation must find a
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freshwater basins to reverse natura
Page 21 and 22: Indicators of Changing States of La
Page 23 and 24: engaged in the preparation and impl
Page 25 and 26: levels below fish in the marine foo
Page 27 and 28: LME observations are integrated int
Page 29 and 30: Sea surface temperature: The Earth
Page 31 and 32: een applying ecosystem-based method
Page 33 and 34: Figure 14. Value of reported landin
Page 35 and 36: 3) Pollution and Ecosystem Health M
Page 37 and 38: The Global Environment Facility (GE
Page 39 and 40: eing used to hindcast and forecast
Page 41 and 42: Using N yield (kg N per km 2 waters
Page 43 and 44: ecosystems (Galloway et al. 2004) w
Page 45 and 46: Somali Coastal Current Guinea Curre
Page 47 and 48: At the LME scale, Hoagland and Jin
Page 49 and 50: are all actively involved in reachi
Page 51 and 52: waste disposal, transportation, rec
Page 53 and 54: The paradigm shift toward ecosystem
Page 55 and 56: Hoagland P, Jin D. 2006. Accounting
Page 57: Trenberth KE, Jones PD, Ambenje P,
Page 60 and 61: Figure 1. The Benguela Currrent Lar
Page 62 and 63: The workshop used a logic framework
Page 64 and 65: The institutional arrangements outl
Page 66 and 67: The Benguela Current Commission sta
Page 68 and 69: November 2006. LMEs, GOOS, GEOSS an
Page 70 and 71: Benguela - Current of Plenty 2008 -
Page 74 and 75: Since the 1940s, the accelerated in
Page 76 and 77: Over the years the BSRP has produce
Page 78 and 79: and with the Swedish Meteorological
Page 80 and 81: Landings in Baltic Sea LME Figure 3
Page 82 and 83: has been instrumental in the prepar
Page 85 and 86: Changing States of the Yellow Sea L
Page 87 and 88: The Yellow Sea LME lies in the warm
Page 89 and 90: As a result, larger, higher trophic
Page 91 and 92: Figure 6. Serious eutrophication, h
Page 93 and 94: competitive species uses the surplu
Page 95 and 96: system based on sustainable food pr
Page 97 and 98: Some Considerations of Fisheries Ma
Page 99 and 100: already happened. Moreover, most fi
Page 101 and 102: important scientific information to
Page 103 and 104: (i) IMTA of abalone and kelp Figure
Page 105 and 106: The purpose of this activity is to
Page 107 and 108: UNDP/GEF (2007a) Transboundary diag
Page 109 and 110: The IUCN Support of Marine Protecte
Page 111 and 112: potential of coastal and marine fis
Page 113 and 114: activities to support local uses of
Page 115 and 116: The percentage of protection is sti
Page 117 and 118: women, were further key aspects of
Page 119 and 120: Future Needs of the LME Approach Wo
Page 121 and 122: those goals in mind, BCLME became a
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2007 was a step in that direction.
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Outreach and Education for Ecosyste
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A second phase, from the mid 1990s
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acidification and nutrient over-enr
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Tide” that surprised me is that i
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The UNEP LME Report (2008): Global
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Sherman K, Hempel G, editors. 2008.
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ANNEX 1986 Vol. 1 1989 Vol. 2 Publi
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1991 Vol. 4 1993 Vol. 5 Sherman, K.
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of the United States H. A. Walker K
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25. Summary and recommendations E.
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Part IV. Assessment of ecologic str
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2003 Vol. 12 dynamics 8. Physico-ch
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14. Applications of the large marin
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