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591.
Chowdhury R 《Environmental management》2005,35(6):716-725
Despite advances in short-range flood forecasting and information dissemination systems in Bangladesh, the present system is less than satisfactory. This is because of short lead-time products, outdated dissemination networks, and lack of direct feedback from the end-user. One viable solution is to produce long-lead seasonal forecasts—the demand for which is significantly increasing in Bangladesh—and disseminate these products through the appropriate channels. As observed in other regions, the success of seasonal forecasts, in contrast to short-term forecast, depends on consensus among the participating institutions. The Flood Forecasting and Warning Response System (henceforth, FFWRS) has been found to be an important component in a comprehensive and participatory approach to seasonal flood management. A general consensus in producing seasonal forecasts can thus be achieved by enhancing the existing FFWRS. Therefore, the primary objective of this paper is to revisit and modify the framework of an ideal warning response system for issuance of consensus seasonal flood forecasts in Bangladesh. The five-stage FFWRS—i) Flood forecasting, ii) Forecast interpretation and message formulation, iii) Warning preparation and dissemination, iv) Responses, and v) Review and analysis—has been modified. To apply the concept of consensus forecast, a framework similar to that of the Southern African Regional Climate Outlook Forum (SARCOF) has been discussed. Finally, the need for a climate Outlook Fora has been emphasized for a comprehensive and participatory approach to seasonal flood hazard management in Bangladesh. 相似文献
592.
ABSTRACT: A methodology has been developed to predict the responses of a range of water supply sources in Wales to global warming scenarios. Hydrologically effective rainfall is predicted from temperature and precipitation for each season based on site specific formulae developed using the Meteorological Office Rainfall and Evaporation Calculation System (MORECS) and UK Surface Water Archive databases. Comparisons are then made between the effects predicted for the scenarios established from equilibrium simulations and the new Hadley Centre High Resolution Model (UKHI) transient mode results. Though very different, both suggest increased stress on water resources late in the hydrological year. 相似文献
593.
Studies of two samples of 24 selected local planning authorities (LPAs) in the UK were undertaken to determine the effect of environmental assessment (EA) regulations on planning practice during their first 18 months of operation. EA has been integrated into the UK planning system without significant recourse to the courts and many LPAs regarded EA as a worthwhile and helpful procedure. However, several LPAs did not consider whether to request EA for projects that might be likely to have significant impacts and some LPAs did not follow statutory and recommended consultation procedures. LPAs did not evaluate environmental statements systematically and their quality was often unsatisfactory. However, mitigation of environmental impacts took place in many cases though two‐fifths of the 20 determined applications involving EA were refused. Half the decisions took longer than the 16‐week time limit. While practice is evolving as experience is gained, there is obvious scope for further improvement and suggestions are made to enhance the contribution of EA to the planning system. 相似文献
594.
R. Kent Jones John T. Dale 《Journal of the American Water Resources Association》1977,13(5):1007-1019
ABSTRACT: Worldwide development of water resources and control of pollution would be improved by the ability for direct, multilateral communication between workers in the dozens of different language communities involved. Current language-based problems which should be eliminated include (1) incomplete diffusion of scientific knowledge, (2) technical inbreeding, (3) unsatisfactory international conferences, (4) money wasted on translation, and (5) unstandardized technical terminology. General education in a common second language for international use can eliminate these conditions. Ethnic languages are not qualified for this purpose, because of their national biases and extreme learning difficulties. The Esperanto language is free of these limitations, and its application is recommended as a means for improving the overall performance of the industry. 相似文献
595.
In discussions concerning the possible construction of a Panamá sea-level canal it has been assumed that Gatún Lake, part of the present canal, acts as a fresh-water barrier to the migration of marine animals from either end of the Canal to the other. Methodical documentary salinity determinations have not been made previously, and only a few surface salinity observations have been recorded. Determinations of salinity-temperature profiles made in spring and fall, 1972, show essentially freshwater to be present from Miraflores Lake, through the Pedro Miguel Locks, through Gatún Lake, to, and including, the upper chambers of the Gatún Locks. With the exception of those of the lower chamber of the Miraflores Locks, the profiles indicate homogeneity and thorough vertical mixing of all water masses in the lock systems and lakes of the canal. Homogeneity of the water in the lock chambers is thought to be due to turbulence during filling of the chambers, to the piston-effect of large ships moving into the chambers, to the action of ships' propellers, and to density currents established as the lock gates are opened. Water in the approach channel at the Pacific end appears to be more homogeneous than that at the Atlantic end. The Panama Canal does, in fact, constitute a fresh-water barrier to the migration of the stenohaline marine biota of the Pacific and Atlantic Oceans. 相似文献
596.
This paper explores the prospects for combining elements of the ecological and policy sciences to form a substantive and effective science of ecological policy design. This exploration is made through a case study whose specific focus is the management problem posed by competition between man and an insect (the spruce budworm, Choristoneura fumiferana) for utilization of coniferous forests in the Canadian Province of New Brunswick. We used this case study as a practical testing ground in which we examined the relative strengths, weaknesses, and complementarities of various aspects of the policy design process. Where existing approaches proved wanting, we sought to develop alternatives and to test them in turn. In particular, we used a combination of simulation modeling and topological approaches to analyze the space-time dynamics of this ecosystem under a variety of natural and managed conditions. Explicit consideration was given to the development of invalidation tests for establishing the limits of model credibility. An array of economic, social, and environmental indicators was generated by the model, enabling managers and policy makers to evaluate meaningfully the performance of the system under a variety of management proposals. Simplified versions of the models were constructed to accomodate several optimization procedures, including dynamic programming, which produced trial policies for a range of possible objectives. These trial policies were tested in the more complex model versions and heuristically modified in dialogue with New Brunswick's forest managers. We explored the role of utility functions for simplifying and contrasting policy performance measures, paying special attention to questions of time preferences and discounting. Finally, the study was shaped by a commitment to transfer the various models and policy design capabilities from their original academic setting to the desks and minds of the practicing managers and politicians. An array of workshops, model gaming sessions, and nontraditional communication formats was developed and tested in pursuit of this goal.This paper reports some specific management policies developed, and some general lessons for ecological policy design learned in the course of the study. 相似文献
597.
598.
P. Hill C. Marshall H. Harmens D. L. Jones J. Farrar 《Water, Air, & Soil Pollution: Focus》2004,4(6):177-186
Soil respiration is a large C flux which is of primary importance in determining C sequestration. Here we ask how it is altered by atmospheric CO2 concentration and N additions. Swards of Lolium perenne L. were grown in a Eutric cambisol under controlled conditions with and without the addition of 200 kg NO
3
–
–N ha–1, at either 350 ppm or 700 ppm CO2, for 3 months. Soil respiration and net canopy photosynthesis were both increased by added N and elevated CO2, but soil respiration increased proportionately less than fixation by photosynthesis. Thus, both elevated CO2 and N appeared to increase potential C sequestration, although adding N at elevated CO2 reduced the C sequestered as a proportion of that fixed relative to elevated CO2 alone. Across all treatments below-ground respiratory C losses were predicted by root biomass, but not by soil solution C and N concentrations. Specific root-dependent respiration was increased by elevated CO2, such that belowg-round respiration per unit biomass and per unit plant N was increased. 相似文献
599.
600.
Jefferson Fox Rebekah Kanter Sanay Yarnasarn Methi Ekasingh Royce Jones 《Environmental management》1994,18(3):391-399
This research has two interrelated objectives. The first is to determine the extent to which a relationship exists between
farmer characteristics and farming practices in three villages in northern Thailand. The second is to use standard statistical
methods for incorporating spatial variables into the analysis and to assess the effects of these variables on farmer decision
making. The data base includes information on the location and size of villages, roads, streams, and fields; a digital elevation
model with information on elevation, slope, and aspect; and information keyed to individual fields on crops and cropping methods
and the ethnicity, income, and religion of farmers. The map data (517 plots) were entered into a computerized geographic information
systems (GIS). Results suggest several hypotheses about the relationships between land use and owner characteristics. More
significantly, the study concludes that spatial analysis appears to be most useful when the dependent variable is either continuous
or ordinal. The outlook is not quite as optimistic when the dependent variable is a nonordinal categorical variable. Before
spatial analysis can be applied regularly to social science data, better computational tools need to be developed. 相似文献