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71.
The process of locating waste disposal sites in the Eastern Caribbean country of Grenada illustrates important lessons in the implementation of new international mandates to invite stakeholder participation in projects with environmental and social impacts. This case study analyzes the participatory methods and results of the World Bank-funded project in Grenada, including an unexpected shift in the policy agenda toward habitat protection for the elusive Grenada Dove, the national bird of Grenada. We conclude that the impact of new requirements for stakeholder inclusion by funding agencies such as the World Bank and Global Environmental Facility has been palpable, but mixed. As the catalysts of more participatory methods, funding agencies still must give more careful consideration to the methods by which their participatory requirements are implemented. In particular they must develop more effective knowledge of and relationships with a broader range of stakeholders than are routinely considered by existing methods, allow for and learn from unexpected contingencies, and be flexible as to project goals and methods.  相似文献   
72.
Importance of insects in environmental impact assessment   总被引:9,自引:0,他引:9  
Insects are particularly suited for use in environmental impact assessment (e.i.a.) because of their high species diversity, ubiquitous occurrence, and importance in the functioning of natural ecosystems. Examples are given of the use of insects in the predictive phase of e.i.a., in the monitoring and assessment phase, and in the much rarer instance of an e.i.a. that includes both of these phases. The importance of working at the species level to understanding the results of e.i.a. is emphasized.  相似文献   
73.
The estuary Byfjord (Sweden) is characterized by high primary production, a well developed meiofauna compared to the macrofauna, high epifaunal biomass, a low number of herbivorous copepods and a small fish stock. A simplified energy flow model of the ecosystem of the fjord is given. The energy transfer is approximated to 15%. About one-fourth-300 (metric) tons of carbon — of the annual primary production is suggested to be directly consumed and to produce 5 tons of zooplankton carbon and 40 tons of epifaunal (mainly Mytilus edulis) carbon. About 500 tons of carbon from the detritus pool are probably utilized in animal production. This amount will produce 5 tons of zooplankton carbon, 6 tons of meiofaunal carbon, and 3 tons of carbon from the benthic macrofauna. Production of fish is estimated at 0.3 ton carbon per year. M. edulis seems to be the only food resource in the fjord worth harvesting by man.  相似文献   
74.
Scanning electron micrographs revealed growth increments in the primary shell layer of the extant terebratulid brachiopod Terebratalia transversa collected from Anacortes, Washington, USA, during the summers of 1982–1984. The increments extend into the secondary shell layer, but only as poorly-defined continuations. Growth increments narrow and widen cyclically, producing patterns similar to tidally-induced, fortnightly growth patterns in bivalve molluscs. Asymmetric increments or doublets that consist of paired wide and narrow bands present additional evidence that the growth pattern is produced by the interference of tidal (24 h 50 min) and solar (24 h) daily environmental influences on growth, as is the case in bivalves. Growth increments are relatively well-defined in specimens from tidal habitats and are poorly-defined in subtidal specimens. Specimens grown in laboratory aquaria and subjected to simulated tidal emersions and submersions had well-defined increments, whereas those that were continuously submerged in aquaria had poorly-defined increments, paralleling the distinctness in growth increments produced at various depths in the natural habitat. Production of growth increments in T. transversa may be related to valve movement and changes in mantle-cavity pH. When the valves are closed, pH drops and, when they are open, pH rises. Highperformance liquid chromatography (HPLC) of mantle tissue and fluid failed to detect any single organic acid that could have been responsible for the pH changes, confirming that intermediate metabolism in T. transversa is very low compared to that of bivalve molluscs. Calculations indicate that cycles in intermediate metabolism may nevertheless be responsible for cycles in growth-increment production and shell dissolution.Please address all correspondence to Dr. G.D. Rosenberg in Indianapolis  相似文献   
75.
ABSTRACT: The El Nino/Southern Oscillation (ENSO) phenomena alter global weather patterns with consequences for fresh water supply. ENSO events impact regions and their natural resource sectors around the globe. For example, in 1997 and 1998, a strong El Nino brought warm ocean temperatures, flooding, and record snowfall to the west coast of the United States. Research on ENSO events has improved long range climate predictions, affording the potential to reduce the damage and economic cost of these weather patterns. Here, using the Hydrologic Unit Model for the United States (HUMUS), we simulate the impacts of four types of ENSO states (Neutral, El Niño, La Niña, and strong El Niño) on water resources in the conterminous United States. The simulations show that La Niña conditions increase water yield across much of the country. We find that water yield increases during El Niño years across the south while declining in much of the rest of the country. However, under strong El Niño conditions, regional water yields are much higher than Neutral, especially along the West Coast. Strong El Niño is not simply an amplification of El Niño; it leads to strikingly different patterns of water resource response.  相似文献   
76.
The rate and extent of ?-caprolactam degradation in aquatic systems are dependent on the nutrient availability, indigenous microbial population and activity, chemical concentration, and water temperature. The labeled chemical evolved 14CO2 indicating ring cleavage with between 35 and 80% of the radioactivity evolved as 14CO2 after 21 days in yeast extract-supplemented waters. The percent of caprolactam degraded was indirectly related to the chemical's concentration in the water, suggesting microbial inhibition at high caprolactam concentrations.  相似文献   
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