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521.
Putting the principles of the Sustainable Livelihoods Approach into fisheries development policy and practice 总被引:1,自引:1,他引:1
The Sustainable Livelihoods Approach (SLA) combines a conceptual framework with a set of operational principles to provide guidance on policy formulation and development practice. The SLA has been widely used in coastal and fisheries development research and has informed the design of development programmes but experience of operationalising it remains largely undocumented. In the Sustainable Fisheries Livelihoods Programme, which involves 25 West African countries, the SLA has helped to align fisheries policy with wider poverty reduction initiatives and to identify means of contributing to poverty reduction that do not directly increase pressure on fully or over-exploited fish resources. 相似文献
522.
523.
A study of the phytoplankton community and water column chemistry in Kaneohe Bay, Oahu, Hawaii, before and after the diversion of secondary treated sewage from the bay has shown that changes in total nutrient concentrations in the water column cannot be accurately predicted without taking into account water column-benthos interactions. During the first year after sewage diversion, the decomposition of about 400 tonnes of benthic organisms, primarily filter feeders, resulted in water column dissolved organic nitrogen and phosphorus concentrations roughly an order of magnitude higher than those expected in the absence of such interactions. The biomass of phytoplankton appears to have been N limited both before and after sewage diversion, with internal nutrient recycling accounting for 70–99% of phtyoplankton nutrient uptake. Both the biomass and growth rate of the phytoplankton declined as a result of the sewage diversion, with post-diversion growth rates evidently well below nutrient-saturated values. Since the principal stresses on the bay's coral reef community as a result of the sewage discharges appear to have resulted from the elevated concentrations of plankton in the water, various measures of seston concentration appear to be the most ecologically significant indicators of nutrient enrichment in this system. 相似文献
524.
Soon-Sup Lee Jong-Kap Lee Beom-Jin Park Dong-Kon Lee Soo-Young Kim Kyung-Ho Lee 《Ocean Engineering》2006,33(13):1814-1828
In this paper, internet-based ship technical information management system has been developed as a means to accumulate, manage, share and utilize various distributed applications and information used for ship design and building. The information managed in the system is documents from the whole life cycle including concept design, basic design, detailed design, construction, operation and maintenance. In addition, using the developed system, integrated system framework is also proposed to integrate applications and database in concurrent engineering environment. 相似文献
525.
The process of embryogenesis and larval development of the asteroid sea star Asterias amurensis (Lütken) was observed, with
special attention paid to morphological change and larval duration. In reproductive season, mature sea stars were collected
under floating net cages, located in Tongyeong, southern Korea. The mature eggs are 138 μm in average diameter, semi-translucent
and orange in color, sperms in good condition appear light cream to white-gray in color. Embryos develop through the holoblastic
equal cleavage stage and a wrinkled blastula stage that lasts about 9 hours after fertilization. Gastrulae bearing an expanded
archenteron hatch from the fertilization envelope 22 hours after fertilization. At the end of gastrulation, rudiments of the
left and right coelom are formed. By day 2, larvae possess complete alimentary canal and begin to feed. At this stage, the
larva is called early bipinnaria. In 6day-old larvae, the pre- and post- oral ciliated bands form complete circuits and the
bipinnarial processes start to develop. By day 12, the lateral and anterior projection of the larval wall processes along
the ciliated bands begins to thicken and curl, and the ciliated bands become more prominent. By day 32, early brachiolaria
are presented with three pairs of brachiolar arms. Advanced brachiolaria with a well-developed brachiolar complex (three pairs
of brachia and central adhesive disc) occur 6 weeks after fertilization. In the field, spawning of the sea star was observed
in April to May, settlement form larvae and just settlements seem to occur from June to July, and early juveniles occur from
August to September. Although we had not described the end of brachiolaria stage, it can be tentatively estimated that the
duration of the pelagic stage of A. amurensis is 40 to 50 days. 相似文献
526.
Young-Hyang Park 《Progress in Oceanography》1986,17(3-4)
Water characteristics of the Yellow Sea Warm Current and its movement in summer are examined from the analysis of the recent hydrographic data collected in adjacent seas of Cheju Island. It is suggested that the Yellow Sea Warm Current water in the northeastern China Sea is a mixture of Western North Pacific Central Water and the Yellow Sea Bottom Cold Water in the ratio of 7 to 3. It is characterized by salinities of 34.2 < S < 34.5% and temperatures of 13 < T < 15°C at depths below 50 m. The Yellow Sea Warm Current does not seem to extend into the Yellow Sea as previously believed, at least in summer, but instead it turns eastward around Cheju. 相似文献
527.
Paul Farrimond Paul Comet Geoffrey Eglinton Richard P. Evershed Michael A. Hall David W. Park Anthony M.K. Wardroper 《Marine and Petroleum Geology》1984,1(4):340-354
Results are presented from an organic geochemical investigation of a suite of rock samples taken from the Upper Kimmeridge Clay near Kimmeridge, Dorset. All samples contain immature organic matter of marine origin, although one horizon, the Whitestone Band, contains an additional secondary input of partially biodegraded mature hydrocarbons, due to an oil seepage of unknown origin. With the exception of increased relative abundances of 4-methylsteroidal hydrocarbons in the more organic-rich samples, the immature molecular distributions are very similar, suggesting a consistent source of organic matter. The results are in agreement with the palaeoenvironmental model proposed by Tyson et al. (1979) for the deposition of the Kimmeridge Clay, where the different lithologies are controlled by a fluctuating oxic/anoxic boundary, with only the organic-poor mudstones being deposited in relatively oxygenated waters. 相似文献
528.
John J. Stegeman Bruce R. Woodin Sang S. Park Pamela J. Kloepper-Sams Harry V. Gelboin 《Marine environmental research》1985,17(2-4)
Monooxygenase reactions catalyzed by cytochromes P-450 are paramount in the oxidative metabolism of many xenobiotics, determining both the persistence and effects of numerous types of compounds. Immunological probes are proving useful in evaluating the functions of P-450 isozymes in microsomal preparations from many species. The regulation of specific isozymes by endogenous and exogenous factors can also be evaluated with such probes. Here we describe studies on the activities apparently catalyzed by induced P-450 in fish, evaluated with both polyclonal and monoclonal antibodies to cytochrome P-450E, the apparent major β-naphthoflavone(BNF) or methylcholanthrene(MC)-inducible isozyme purified from scup (S. chrysops) liver. 相似文献
529.
Hoi-Soo Jung Kap-Sik Jeong Yong-Shik Chu Sung-Hyun Park Ki-Hyune Kim 《Marine Georesources & Geotechnology》2001,19(3):181-195
Grain size and water content in box-core sediments from the Clarion-Clipperton fracture zone (C-C zone) in the northeast equatorial Pacific were analyzed in detail to understand the downcore variations across a hiatus between Quaternary and Tertiary layers. Grain-size distributions in the topmost core sediments show two modes: a coarse mode (peaked at 50 μm) and a fine mode (at 2-25 μm). The coarse mode disappears gradually with depth accompanied by the dissolution of siliceous fossil tests, whereas the fine mode coarsens due to the formation of authigenic minerals. Water content increases abruptly across a color boundary between an upper pale brown layer and a lower dark brown layer that is the hiatus between Quaternary and Tertiary layers. Abundant smectites and microvoid molds, which are created by the prolonged fossil dissolution in the underlying sediment, are attributed for the abrupt downcore variation of water content. Overall variations in grain size and water content in the topmost core sediments in the western C-C zone are possibly constrained by the dissolution of biogenic siliceous fossils. Variations in geotechnical properties related to these changes must be considered in the design of nodule collectors. 相似文献
530.
Benthic amphipod,Grandidierella japonica widely inhabits the Korean coastal waters and is developed as a standard test species for sediment toxicity tests. We exposedG . japonica to various pollutants including 4 kinds of inorganic metals (Ag, Cd, Cu and Hg), tributyltin [TBT], ammonia and 7 polycyclic
aromatic hydrocarbon (PAH) compounds (acenaphthene, chrysene, fluoranthene, fluorene, naphthalene, phenanthrene and pyrene)
to estimate the no observed effect concentration (NOEC) and the median lethal concentration (LC50) of each pollutant during
the 96-hour acute exposure. Among all tested pollutants, TBT was most toxic toG. japonica, and Hg was most toxic among inorganic metals. The toxicity of pyrene toG. japonica was greatest among PAH compounds, followed by fluoranthene, phenanathrene, acenaphthene, fluorene and naphthalene. The toxicity
of PAH compounds was closely related to their physico-chemical characteristics such as Kow and water solubility.G. japonica responded adequately to pollutant concentrations and exposure durations, and the sensitivity ofG. japonica to various inorganic and organic pollutants was generally comparable to other amphipods used as standard test species in
ecotoxicological studies, indicating this species can be applied in the assessment of environments polluted by various harmful
substances. 相似文献