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91.
92.
To facilitate precise and cost-effective watershed management, a simple yet spatially and temporally distributed hydrological model (DHM-WM) was developed. The DHM-WM is based on the Mishra-Singh version of the curve number method, with several modifications: The spatial distribution of soil moisture was considered in moisture updating; the travel time of surface runoff was calculated on a grid cell basis for routing; a simple tile flow module was included as an option. The DHM-WM was tested on a tile-drained agricultural watershed in Indiana, USA. The model with the tile flow module performed well in the study area, providing a balanced water budget and reasonable flow partitioning. The daily coefficient of determination and Nash-Sutcliffe coefficient were 0.58 and 0.56, for the calibration period, and 0.63 and 0.62 for the validation period. The DHM-WM also provides detailed information about the source areas of flow components, the travel time and pathways of surface runoff.
EDITOR A. Castellarin; ASSOCIATE EDITOR F.-J. Chang  相似文献   
93.
考虑应用系统中如何安全、高效的进行统一的人员管理及权限管理问题,研究基于微软活动目录构建通用中间件并以WebService方式发布的解决方案。具体内容包括把活动目录作为统一的人员库;构建通用授权管理平台统一管理用户在不同的软件系统中的角色和权限;该管理平台以WebService的方式向其它的应用系统提供接口。文中示例表明该方案切实可行,应用范围广。  相似文献   
94.
Participatory fisheries management has been increasingly proposed as a useful management approach to address fisheries problems. However, the criteria regarding its applicability and measures of success still seem unclear. This study reviews the main concepts and theory behind two participatory resource-management approaches and compares them to the reality of fisheries management in Costa Rica. The analysis shows that while the implementation of a participatory approach in fisheries management should be encouraged, it is essential to keep in mind the possible limitations these approaches have. Furthermore, it seems important to improve institutional coordination and develop social, legal and economic policies that will allow the state, together with coastal communities, to contribute in an effective way to fisheries management.  相似文献   
95.
96.
Following the decision in 2007 by the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) to include European eel Anguilla anguilla on its Appendix II, and the 2010 ban of all eel exports by EU member states, a shift has occurred to tropical Asian eel species to meet the demand from East Asia. Here the focus is on the role Indonesia played in fulfilling this demand using official export figures, reports in the Indonesian media and government documents. Despite Indonesia first putting in place restrictions on the export of eel in 1974 the export has increased exponentially over the last 25 years. Prior to the EU ban it exported ~1.4 million kg/year. With the infrastructure in place, and close trade links to East Asia, and helped by government encouragement, Indonesia was in an excellent position to step in where the EU posed restrictions. Exports increased to 3.2 million kg/year (2007–2009), to 4.0 million kg/year (2010–2012), and to 6.1 million kg (2013). The interest in eel trade in Indonesia increased in parallel with the exports. From 2010 onwards the searches for the Indonesian equivalent of eel (“ikan sidat”) became frequent enough for it to be picked up by Google Trends. Indonesia is home to five species of eel, and while it is unclear in what quantities each is traded, Indonesian media reports suggest that the majority comprises A. bicolar and A. marmorata. More stringent management schemes, possibly including CITES-listing, and better monitoring are needed to ensure that international trade is not an impediment to the conservation of tropical eels.  相似文献   
97.
Achieving a balance between fishing capacity and fishing opportunities is one of the major challenges in European fisheries. One way to achieve this is to introduce individual tradable quotas or similar management measures. In several mackerel and herring fisheries in the Northeast Atlantic, such systems have already been introduced on a national basis and the long term economic gains of this have been acknowledged. This paper takes this a step further and investigates the potential economic gains from introducing individual tradable quotas between countries. Overall, the results show that the gross cash flow can be improved by 21% by allowing the mackerel and herring quotas to be traded internationally in the Northeast Atlantic. This rent gain arises mainly from increased productivity by allowing tradability between areas and fleets. The analysis also shows that the Danish pelagic fleet will gain from increasing its share of mackerel and herring quotas, whereas the Irish fleets are incentivised to sell quota, if individual quotas are allowed to be traded among countries. This result is in line with the qualitative analyses that show that Irish fishermen targeting herring in the Celtic Sea are negatively oriented towards international individual tradable quotas, whereas the Danish pelagic fishermen have strong preferences for international individual tradable quotas.  相似文献   
98.
Non-indigenous species (NIS) can create significant risks when introduced to foreign ecosystems. One of the many vectors facilitating the global transport of NIS is ballast water, and as commercial shipping increases so does the threat of ballast water-mediated introductions. Despite Canadian regulations, consistent with international guidelines put forth by the International Maritime Organization in the early 1990s, ballast water remains a potential vector for the introduction of many NIS to Canadian marine ecosystems: there have been no new introductions in the Laurentian Great Lakes Region since 2006, yet marine ecosystems continue to see the introduction and establishment of NIS. This paper details and analyzes the development of Canadian ballast water management (BWM), in the context of marine ecosystems, and identifies issues therein. BWM in Canada has a number of management gaps that have persisted since large-scale BWM began in the late 1980s. These include BWM exemptions for vessels not exiting the North American continental shelf, and limitations of effectiveness of mid-ocean exchange as the predominant management method in marine ecosystems. In addition, ballast water regulations for the Canadian Arctic may require additional consideration as the Arctic will likely continue to see an increase in both warming and commercial shipping in the future, thereby increasing the potential risk of NIS. In order to adequately protect all Canadian marine ecosystems, it is recommended that the current BWM regime: fill gaps in management to help prevent further introduction and spread of NIS; focus equally on both marine and freshwater regions, and; look to other aggressive BWM strategies such as those being developed by the state of California.  相似文献   
99.
Recent changes in marine policy in Panama are closely related to sustained expansion of the Panamanian economy in the past ten years. Important drivers of economic growth such as the Panama Canal expansion, tourism, and real estate development directly involve marine and coastal areas. Therefore, maintaining the quality of these environments, as well as the sustainability of the human communities that depend on them, calls for the implementation of adequate management and planning policies. In light of a complex history of marine and coastal policy in Panama, current institutional restructuring processes, and a growing recognition of the importance of marine and coastal geographies, the authors aim to document the current status of, and community response to, marine and coastal policy in Panama, analyzed in terms of three important cross-cutting sectors: tourism, fishing, and conservation. To do so, the authors introduce two case studies: one in the Pearl Islands Archipelago and one in Bocas del Toro, each with varying degrees of participation or involvement in each sector, to illustrate the range of adaptations to change occurring in coastal communities. Based on an in-depth policy analysis and the case studies, the authors suggest that there are important administrative and structural gaps in the legislation and institutions that enforce them, as well as a lack of integration across institutions. In particular, the authors highlight the lack of clear marine and coastal property regimes as an obstacle to the implementation of integrative marine policies in Panama.  相似文献   
100.
The sustainable management and profitable development of the Pacific island tuna fisheries is the key ocean governance challenge for the Pacific islands region in the short and medium term. Resolving these challenges is fundamental to the long term future of the region and its ability to implement oceans governance across all resource and conservation concerns.  相似文献   
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