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This article follows the transformation process in the fishing industry with specific reference to the emergence of a limited commercial sector. In the policy domain, this sector was accommodated through a “one size fits all approach” to access rights, requiring it to compete with the large-scale commercial sector for the same resources. The strategies and actions of successful and unsuccessful applicants in four fishing communities in South Africa are examined. The paper identifies the key challenges facing the limited commercial sector as being the lack of skills to complete the application process, start up capital or credit, organisation and financial and business acumen. It highlights the disjuncture between the Marine Living Resources Act's stated aims of sustainability, equity and stability and the realities of implementation at a grassroots level. 相似文献
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On 1 December 2007, eight ‘Small Island Developing States’ in the Western and Central Pacific Ocean implemented a management regime restricting the total number of days fished by tuna purse seine vessels within their waters, commonly referred to as the Vessel Day Scheme (VDS). The VDS is seen as one component of management arrangements to reduce fishing mortality on bigeye and yellowfin tuna, constrain fishing effort, and increase the rate of return from access fees by Distant Water Fishing Nations. 相似文献
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H. Hellmann 《洁净——土壤、空气、水》1996,24(5):218-225
IR Spectroscopy and Further Analyses of New Fabric Rinse Agents Distearyldimethylammoniumchloride (DSDMAC) that dominated the fabric softener market in Germany in the past is now substituted by three new types of ester-based agents, i.e. imidazoline ester, ester quats, and diester quats what poses new challenges to surface water analytics. The IR spectra and the chromatographic behaviour of these three agents are more or less similar to those of naturally occuring fatty esters. The paper reports about the use of IR spectroscopy, its benefit in the sense of fingerprinting principle, the identification of substances by functional groups, and the analytical tracing of transformation products. The latter relates to the formation of salts with anions that are easily detectable, the clean up, and the final spectroscopic determination. While in 1994 DSDMAC was still determinable in concentrations of 10…20 mg/kg in suspended solids from the Middle Rhine River, the concentration of the substitutes was below the detection limit of 2 mg/kg and 1…2 μg/L in 1995. 相似文献
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近年来随着产业融合的发展趋势显著,第一产业和第二产业开始向第三产业转型,海洋牧场建设发展过程中渔业与旅游业逐渐融合发展形成休闲渔业等渔业旅游形式。许多地区因地制宜形成了不同的休闲渔业发展模式,休闲渔业旅游发展多元化的趋势也在逐渐形成。文章对休闲渔业的概念进行了阐述,介绍了休闲渔业的产生与发展,并对我国休闲渔业的旅游模式进行归纳,提出当前休闲渔业发展存在的问题。如:发展观念滞后,缺乏长远规划;海洋休闲渔业产业结构单一;缺乏高素质的从业人员;科技、资金投入不足等。最后总结了海洋牧场背景下休闲渔业的未来发展趋势并对发展方向提出建议。 相似文献
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Oasis is the core area of social and economic development in the arid western regions, and is also a territory with prominent ecological environmental problems. Because of the unreasonable development and utilization of soil and water resources, the ecological environment of oasis in Qingtongxia Irrigation District is threatened by soil salinization, shrinkage of lakes and wetlands, and deterioration of water environment. As for these environmental problems, the direct cause is the loss of regulation of groundwater depth or serious pollution of water caused by man-made irrational exploitation, and the root cause lies in shortage of water resources and unreasonable allocation of water resources. In this regard, it is believed that the primary task for the construction ecological environment of oasis in Qingtongxia Irrigation District is to adjust the allocation structure of water resources and to ease the contradiction between supply and demand of water resources, for which the direct means is to carry out dynamic control of water and salt based on the ecological landscape structure and land type in the Irrigation District in accordance with local conditions. 相似文献
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Hydroelectric power is an important energy source to meet the growing demand for energy, and large amounts of water are consumed to generate this energy. Previous studies often assumed that the water footprint of hydroelectric power equaled the reservoir’s water footprint, but failed to allocate the reservoir water footprint among the many beneficiaries; dealing with this allocation remains a challenge. In this study, we developed a new approach to quantify the water footprint of hydroelectric power (WFh) by separating it from the reservoir water footprint (WF) using an allocation coefficient (ηh) based on the ratio of the benefits from hydroelectric power to the total ecosystem service benefits. We used this approach in a case study of the Three Gorges Reservoir, the world’s largest reservoir, which provides multiple ecosystem services. We found large differences between the WFh and the water footprint of per unit of hydroelectric production (PWFh) calculated using ηh and those calculated without this factor. From 2003 to 2012, ηh decreased sharply (from 0.76 in 2005 to 0.41 in 2012), which was due to the fact that large increases in the value of non-energy ecosystem services, and particularly flood control. In 2009, flood control replaced hydroelectricity as the largest ecosystem service of water from the Three Gorges Reservoir. Using our approach, WFh and PWFh averaged 331.0 × 106 m3 and 1.5 m3 GJ−1, respectively. However, these values would almost double without allocating water footprints among different reservoir ecosystem services. Thus, previous studies have overestimated the WFh and PWFh of reservoirs, especially for reservoirs that serve multiple purposes. Thus, the allocation coefficient should not be ignored when calculating the WF of a product or service. 相似文献
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We aim to determine the effects of agricultural factors input per hectare on wheat production, and to optimize the allocation of wheat production factors under three scenarios and in different operating modes. Data were collected from 204 farming households using a face-to-face questionnaire. The sampled farms were selected through a stratified random sampling technique. We find fertilizer cost, irrigation cost and machinery cost all positively and significantly affect the per-unit-area wheat production, indicating the labor cost is not the major driving factor on wheat yield increment. Multi-object optimization model is used to allocate the production factors per hectare. We find under the Business as usual (BAU) scenario, the irrigation cost per-hectare wheat production after optimization in 2014 grows at a rate of 24.31% and accounts for 14.9% of total input. Under the Cooperate Environmental Sustainability (CES) scenario, the fertilizer and pesticide costs after optimization drop significantly by 42.83% and 21.41%, respectively. Under the Rapid Benefit Growth (RBG) scenario, the irrigation cost after optimization increase by 2.56% and the fertilizer cost increases by 4.69% compared with the surveyed data. Comparison of optimized data among three operating modes shows that the labor costs at household farm and cooperative farm both increase significantly. Cooperative farms are more successful in production factor use efficiency and economic performance. In conclusion, wheat production at different operating modes could be improved so as to constitute more efficient and economic use of production factors. 相似文献
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珠江三角洲干流汊道泥沙分配及变化--以西、北江三角洲为例 总被引：4，自引：0，他引：4
通过对６０年代和９０年代珠江三角洲河网典型汊河泥沙分配变化的对比分析,认为（１）珠江河口区的泥沙主要来自陆相径流挟带的下行泥沙和随潮流挟带的上溯泥沙,其中径流及其挟带的泥沙是现代珠江三角洲建造过程中的基本动力和物质,起着主导作用,而珠江河口区由径流挟带的悬移质泥沙又主要来自西江。（２）西北江干沙处于逐年淤积的总趋势,其中河流段冲淤变化不大,过渡段有冲有淤,以淤为主,潮流段由是普遍淤积。（４）海平面 相似文献
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厦门经济特区城市发展与布局研究 总被引：1，自引：0，他引：1
陈怡煌 《云南地理环境研究》1991,3(1):74-82
厦门是座海岸一港岛复合型城市。为中国“经济特区—经济技术开发区—沿海经济开放区”有机结合带,它又是全国计划单列城市和福建改革开放综合试验区。多层次的对外开放和多元结构的改革试验,为区域开发、城市空间布局和多功能构建注入了新活力。台湾海峡两岸关系的改善使之成为投资热点,提高了它在完成祖国统一大业中的特殊战略地位。本文以地理学的观点,分析了世界经济特区的基本模式和中国经济特区城市的基本职能,探讨了厦门设置特区的因由、吸引腹地、城市性质、产业开发、城市空间格局,并对特区城市的高新技术开发作了初步论证。 相似文献