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71.
Coastal and island states of the Western Indian Ocean lack scientific and management capacity to draw sustainable benefits from their Exclusive Economic Zones. Declining ecosystem services and unregulated fishing has prompted nine riparian countries to develop a regional framework for capacity building and scientific development towards collective management of shared resources. Supported by the Global Environment Facility (GEF), the Agulhas and Somali Currents large marine ecosystems programme consists of three inter-related modules, supported by different agencies: land-based impacts on the marine environment (UNEP); productivity, ecosystem health and nearshore fisheries (UNDP) and transboundary shared and migrating fisheries resources (World Bank). The latter is the South Western Indian Ocean Fisheries Project (SWIOFP), a 5-year joint data gathering and fisheries assessment initiative. SWIOFP is a prelude to long-term cooperative fisheries management in partnership with the newly established FAO–South Western Indian Ocean Fisheries Commission (SWIOFC). We describe the development of SWIOFP as a model of participatory regional scientific cooperation and collective ocean management.  相似文献   
72.
73.
Microbial communities flourish at gas hydrate occurrences in ocean sediments. Studies are reported in this paper on the laboratory production, separation, characterization and hydrate catalysis of biosurfactants from cultures of the Bacillus subtilis bacterium associated with Gulf of Mexico gas-hydrate accumulations. The B. subtilis bacterium from ATCC 21332 species was cultured anaerobically with glucose as carbon-source to produce surfactin, one of the more potent surface active agents known. The surface-active agent was removed from the broth in foam created by bubbling inert gas through the mixture, and biosurfactant was then recovered from the collapsed-foam distilled water solution by acid precipitation and dichloromethane extraction. According to HPLC spectra, five surfactin isomers were identified in the sample of laboratory-generated biosurfactant. Recovered surfactin was then used to perform gas-hydrate formation studies in porous media saturated with the surfactin-water solution. Gas-hydrate induction time and formation rate determinations showed that the anaerobically-produced biosurfactants catalyzed hydrate formation markedly. The tests suggest prolific surfactin production by the B. subtilis bacterium and of other species under prevailing anaerobic conditions around seafloor gas hydrates that promotes hydrate formation and the propensity of the bioproduct to be dispersed in the porous media by natural gas vents.  相似文献   
74.
Carbonate reservoirs in the Córdoba petroleum system (NE Mexico) passed through a multiphase deformation history complicating the petroleum geology. The area evolved from passive margin and foreland setting to Laramide fold and thrust belt (FTB) that was subsequently buried below the Tertiary-Quaternary Veracruz Basin, which in turn underwent transpressional deformation. Reconstruction of paleo-burial (erosion) and paleo-thermicity through the different zones of the FTB and adjacent foreland is a challenging task since classical calibration tools fail to discriminate between several kinematic and thermal models. In this study results from detailed diagenetic and fluid inclusion (FI) analyses on carbonates from the western part of the Córdoba Platform helped constraining paleo-thermicity. Combined microthermometry, synchrotron FTIR analyses and PVT modeling of cogenetic hydrocarbon-aqueous FI allowed also calculation of absolute pressures. Thermal modeling exercises calibrated with organic maturity parameters, bottom-hole temperatures or temperatures from FI demonstrate that without controlling also paleo-erosion the model results may be misleading.  相似文献   
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