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221.
Inland (floodplain) fisheries remain the most important contributor to fish production in Bangladesh. They have in the past been administered to generate government revenue without due concern for sustainability or equity. Community Based Fisheries Management (CBFM) is a possible solution and was tested in 19 waterbodies (rivers and beels) during 1996-2000. The outcomes so far are assessed with respect to social, institutional, and physical context, and the interactions that arose in establishing CBFM. The lessons drawn are that: it was essential that communities obtained rights over the fisheries, strong facilitation was necessary, taking up visible resource management actions greatly helped, success was more likely in homogeneous communities, external threats were a strong limiting factor, clear boundaries and small fisheries were not so critical, and new institutions could be built with as much ease (or difficulty) as modifying existing ones. Effective well-defined partnerships of NGOs and government were not easy to establish but were sufficiently beneficial that in several locations new community institutions for fisheries management were established. This is a slow process, the sustainability of local management institutions is not yet established, although they continued during an interim period without funding, further phased support is planned to strengthen these organizations and to generate evidence of impacts and momentum to influence wider fisheries policy in and beyond Bangladesh. 相似文献
222.
Utilitarian ethics provides a model for evaluating moral responsibility in agricultural research decisions according to the balance of costs and benefits accruing to the public at large. Given the traditions and special requirements of agricultural research planning, utilitarian theory is well adapted to serve as a starting point for evaluating these decisions, but utilitarianism has defects that are well documented in the philosophical literature. Criticisms of research decisions in agricultural mechanization and biotechnology correspond to documented defects in utilitarian theory. Research administrators can expect that application of a utilitarian standard ignoring these deficiencies will become the occasion for predictable attacks by critics. Administrators who are sensitive to the strengths and weaknesses of utilitarian ethics are equipped to make a better allocation of research effort. 相似文献
223.
224.
Computer and fluid modelling of evacuation 总被引:1,自引:0,他引:1
One of the most important areas in the field of “Life Safety” is the escape movement of individuals in emergency situations It is not yet possible to accurately model very complex psychological reactions, such as panic and confusion, but many parameters can be simulated, especially in the case of crowd movement. These basic parameters include speed fluctuations; crowd flow behaviour, travel distances and overall evacuation time, based upon certain assumptions. The evacuation characteristics of a building can be assessed in different ways. The statutory regulations (BSI, 1983) use general rules based upon the maximum crowd flow rates through specific exit route widths. These figures are based upon data produced in the 1950s (Hankin and Wright, 1958) that were intended primarily for application in building plans with fairly regular room/corridor plan configurations. This paper discusses two techniques for assessing crowd movement: fluid modelling and computer simulation. The fluid modelling is intended to provide a greater degree of understanding about the mechanism of crowd flow. The computer model SIMULEX combines spatial analysis with the escape movement of large numbers of individuals in a building, and is intended for eventual use as a design tool. 相似文献
225.
Mark E. Thompson Herbert H. Stoevener 《Journal of the American Water Resources Association》1983,19(6):889-896
ABSTRACT: An implicit price model relating residential lot value to price determining characteristics of land is developed to measure the benefits of a structural flood control project. Special attention is given to the selection of relevant price determining characteristics of residential lots. An implicit price equation is estimated for both the with and without project conditions. Flood damages are quantified through the use of a dummy variable indicating a flood plain location. The analysis shows that annual flood damages were reduced by $15,275. 相似文献
226.
This study describes the distribution of sewage pollution markers (faecal coliforms, Clostridium perfringens and faecal sterols) in seawater and marine sediments around Rothera Research Station, Antarctic Peninsula. Untreated sewage waste has been released from this site since 1975, creating the potential for long-term contamination of the benthic environment. Faecal coliform concentrations in seawater reached background levels within 300 m of the outfall. In sediment cores, both C. perfringens and faecal coliform concentrations declined with distance from the outfall, though C. perfringens persisted at greater depths in the sediment. High concentrations of 5beta(H)-cholestan-3beta-ol (coprostanol) relative to the corresponding 5alpha-epimer (cholestanol), indicative of sewage pollution, were only found in sediments within 200 m of the sewage outfall. This study has shown that sewage contamination is limited to the immediate vicinity of the sewage outfall. Nevertheless, a sewage treatment plant was installed in February 2003 to reduce this contamination further. 相似文献
227.
An intelligent disaster decision support system for increasing the sustainability of transport networks 下载免费PDF全文
The increase in extreme weather events arising from climate change is posing serious threats to the sustainability of transport systems, creating the need for improved tools for decision support for more effectively managing natural disasters. There are numerous transport‐related decisions that are required during the response, recovery and preparedness stages of the disaster management cycle. This paper describes the development and application of the Intelligent Disaster Decision Support System (IDDSS), which provides a platform for integrating a vast range of road network, traffic, geographic, economic and meteorological data, as well as dynamic disaster and transport models. Initial applications to the response and planning for floods and fires are presented to illustrate some of its capabilities. The IDDSS can be used to improve disaster management, which in turn will increase the sustainability of transport networks. 相似文献
228.
Wiley C. Thompson 《Disasters》2010,34(1):1-15
The modern cast of disaster relief actors includes host nations, non-governmental organisations, private volunteer organisations, military organisations and others. Each group, civilian or military, has valuable skills and experiences critical to disaster relief work. The goal of this paper is to supplement the study of civil–military relief efforts with contemporary anecdotal experience. The paper examines the interaction between US military forces and other disaster relief actors during the 2005 Kashmir earthquake relief effort. The author uses direct observations made while working in Pakistan to contrast the relationships and activities from that effort with other accounts in prevailing scholarly disaster literature and military doctrine. Finally, this paper suggests that the Kashmir model of integration, coordination and transparency of intent creates a framework in which future humanitarian assistance operations could be successfully executed. Recommendations to improve civil–military interaction in future relief efforts will also be addressed. 相似文献
229.
Keith E. Schilling Carol A. Thompson 《Journal of the American Water Resources Association》2000,36(5):1101-1114
ABSTRACT: Land use and surface water data for nitrogen and pesticides (1995 to 1997) are reported for the Walnut Creek Watershed Monitoring Project, Jasper County Iowa. The Walnut Creek project was established in 1995 as a nonpoint source monitoring program in relation to watershed habitat restoration and agricultural management changes implemented at the Neal Smith National Wildlife Refuge by the U.S. Fish and Wildlife Service. The monitoring project utilizes a paired‐watershed approach (Walnut and Squaw creeks) as well as upstream/downstream comparisons on Walnut for analysis and tracking of trends. From 1992 to 1997, 13.4 percent of the watershed was converted from row crop to native prairie in the Walnut Creek watershed. Including another 6 percent of watershed farmed on a cash‐rent basis, land use changes have been implemented on 19.4 percent of the watershed by the USFWS. Nitrogen and pesticide applications were reduced an estimated 18 percent and 28 percent in the watershed from land use changes. Atrazine was detected most often in surface water with frequencies of detection ranging from 76–86 percent. No significant differences were noted in atrazine concentrations between Walnut and Squaw Creek. Nitrate‐N concentrations measured in both watersheds were similar; both basins showed a similar pattern of detection and an overall reduction in nitrate‐N concentrations from upstream to downstream monitoring sites. Water quality improvements are suggested by nitrate‐N and chloride ratios less than one in the Walnut Creek watershed and low nitrate‐N concentrations measured in the subbasin of Walnut Creek containing the greatest amount of land use changes. Atrazine and nitrate‐N concentrations from the lower portion of the Walnut Creek watershed (including the prairie restoration area) may be decreasing in relation to the upstream untreated component of the watershed. The frequencies of pesticide detections and mean nitrate‐N concentrations appear related to the percentage of row crop in the basins and subbasins. Although some results are encouraging, definitive water quality improvements have not been observed during the first three years of monitoring. Possible reasons include: (1) more time is needed to adequately detect changes; (2) the size of the watershed is too large to detect improvements; (3) land use changes are not located in the area of the watershed where they would have greatest effect; or (4) water quality improvements have occurred but have been missed by the project monitoring design. Longer‐term monitoring will allow better evaluation of the impact of restoration activities on water quality. 相似文献
230.
Globally, shrimp farming has had devastating effects on mangrove forests. However, mangroves are the most carbon-rich forests, with blue carbon (i.e., carbon in coastal and marine ecosystems) emissions seriously augmented due to devastating effects on mangrove forests. Nevertheless, integrated mangrove-shrimp cultivation has emerged as a part of the potential solution to blue carbon emissions. Integrated mangrove-shrimp farming is also known as organic aquaculture if deforested mangrove area does not exceed 50% of the total farm area. Mangrove destruction is not permitted in organic aquaculture and the former mangrove area in parts of the shrimp farm shall be reforested to at least 50% during a period of maximum 5 years according to Naturland organic aquaculture standards. This article reviews integrated mangrove-shrimp cultivation that can help to sequester blue carbon through mangrove restoration, which can be an option for climate change mitigation. However, the adoption of integrated mangrove-shrimp cultivation could face several challenges that need to be addressed in order to realize substantial benefits from blue carbon sequestration. 相似文献