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1.
《Marine Policy》2001,25(4):265-279
The objective of this paper is to provide an overview of shrimp aquaculture from the perspectives of economics. It is offered as a contribution to the on-going policy debate on this globally important industry. The paper is organised into four sections: the benefits of shrimp aquaculture, the problems of shrimp aquaculture, economic development perspectives on shrimp aquaculture, and conclusions. Four main conclusions are drawn: there is a lack of independent analysis of the factors affecting the production strategies of private firms in the shrimp industry; there is a need to overcome polarisation in order to promote sustainable shrimp aquaculture; wider perspectives on shrimp aquaculture will be beneficial to policy formation; and it is in the long-run self-interest of shrimp producers to incorporate the external costs of production into planning decisions. The paper includes a review of the international literature which provides a valuable resource for policy-makers. 相似文献
2.
海水养殖是海洋经济重要的组成部分。中国是世界上最大的对虾养殖国,对虾养殖净收益直接影响对虾养殖户的生产积极性,进而影响对虾养殖产业持续稳定健康发展。文章以山东省、江苏省和广东省对虾养殖户的调查数据为依据,运用多元线性回归模型,对对虾养殖净收益的影响因素进行实证分析。结果表明,影响对虾养殖净收益的3个主要因素是:①每年对虾养殖的造数;②是否参加对虾养殖农业合作社;③对虾出塘的销售价格。对虾养殖者的年龄,受教育程度,是否混养其他品种生物,养殖模式,养殖面积对对虾养殖净收益影响不显著。基于回归结果,笔者提出完善对虾养殖基础设施;发展对虾养殖农业合作社和养殖协会;建立稳定的对虾市场价格调控体系等政策建议。 相似文献
3.
The Sundarbans region of West Bengal in India is inhabited by small-scale farmers and traditional rice paddy-cum-prawn cultivators. Recent policy initiatives by the Government of India may facilitate expansion of commercial shrimp aquaculture in the future, setting the stage for potential conflicts between local stakeholders. We used qualitative and quantitative methods to analyse the preferences of local stakeholders for alternative management options related to shrimp aquaculture development in the region. We then derived management recommendations for the development of shrimp aquaculture in the region that would minimize the environmental impacts of shrimp aquaculture, distribute the economic benefits of shrimp aquaculture more equally and develop alternative opportunities for income generation, especially for shrimp Fry Collectors. 相似文献
4.
A desert in the delta: Participatory assessment of changing livelihoods induced by commercial shrimp farming in Southwest Bangladesh 总被引：2，自引：0，他引：2
In recent years, shrimp aquaculture, which is undertaken largely in the tropical countries, has experienced spectacular growth in response to expanding global demand and higher economic return. Shrimp exports bring substantial foreign exchange to the producing countries and also generate employment for various stakeholders related to this industry. Despite a number positive aspects (e.g., foreign exchange, employment and food) of shrimp farming, the industry has serious negative environmental impacts. Because of the degradation of natural resources, commercial shrimp farming imposes socio-economic costs on rural resource-reliant communities as their traditional means of food production and livelihoods are displaced. Bangladesh produces 2.5 percent of the global production of shrimp. The country earned about 400 million dollars (U.S.) from shrimp exports during 2004-2005, up from only US$3.17 million in 1971-72. Bangladesh is suffering because of unplanned expansion of this aquaculture and increasingly called as “a desert in the delta”. The purpose of this paper is to identify the impact of commercial saltwater shrimp farming on rural livelihood patterns in southwest Bangladesh using different Participatory Research methods. The authors suggest that vulnerabilities in livelihoods of the rural communities increased due to narrowing down agricultural production, income sources and natural supply of food. Other socio-economic impacts (e.g., landuse patterns, homestead and family structure, daily movement pattern and activities, drinking water, and law and order) also followed as a reaction to the changing ecological conditions. It is also found that economic benefits from shrimp cultivation to the communities was minimal or even negative due to the polarization and outflow of profits, which is augmenting the threat of poverty. 相似文献
5.
《Ocean & Coastal Management》2003,46(6-7):681-700
The southern Mexican states on the coast of the Gulf of Mexico produce approximately 85% of the total national oil production. The region has also attracted attention due its important economic influence in terms of fisheries, aquaculture and agriculture, and for its ecosystem diversity. The justification for more integrated approaches to aquaculture development is significant, as coastal aquaculture has brought economic and employment benefits to both national economies and coastal people. The aim of this study is the analysis of Mecoacan fishing communities’ perception on coastal resources management and to assess group awareness of the potential benefits and impacts of coastal aquaculture. Although aquaculture practices have been implemented as an alternative to fishing and to improve current levels of fisheries production, the results showed that conditions within Mecoacan fisheries have deteriorated significantly, as collective aggregation is not producing a positive outcome for the local communities. However, fishermen regarded the restructuring of fishing organisations as a means of integrating employment and income generation alternatives such as aquaculture practices. Therefore, a key to success will be to demonstrate the ability of good coastal management to promote capacity building within coastal communities in the context of a participatory intervention strategy through formal and informal organisations. 相似文献
6.
《Marine Policy》2017
The global aquaculture sector has grown continuously over the past 40 years, though unevenly among countries. Differences in factors such as inputs, climate, management, technology, markets, social environment, and institutions might be reasons for the disparities in growth. This study focuses on institutions, by analyzing the relationship between annual growth in the production of the major aquaculture countries and the quality of their institutions over three decades (1984–2013). Based on an ex-ante set of criteria, seventy-four aquaculture countries from five different regions - Africa, the Americas, Asia, Europe and Oceania - were selected. Annual percentage change in total aquaculture production, in terms of quantity and value, was used as a proxy for sector development. Three indices - governance, corruption, and competitiveness - were used as institutional quality proxies. Empirical results suggest that the aquaculture growth did not significantly correlate with the quality of institutions. By region, Africa had the fastest growth in the aquaculture sector, though from a low base, with 7.35% and 9.28% higher annual percentage change in aquaculture quantity and value respectively, than the Asian region. While, the European region experienced significantly lower annual percentage change in aquaculture quantity, a difference of 3.78% compared to the Asian region. Furthermore, the study found that total aquaculture production was not positively correlated with eco-label certification. The study is concluded by discussing the “aquaculture paradox.” 相似文献
7.
In the Mexican coasts, as in many tropical and subtropical coastal areas, shrimp culture grew exponentially over the last three decades. This process has produced an intense debate on the economic benefits but also about the extent and intensity of the impact of this activity on the coastal ecosystems, particularly the effects of pond construction on mangrove areas and other coastal wetlands. For the Northern coast of Sinaloa (Northwest Mexico), a region where shrimp culture is actively practiced and reproduces most of the shrimp controlled production model in Mexico, a land cover change-detection analysis, with Landsat images, outputs that 75% of the shrimp farming in this region has been built on saltmarshes while less than 1% was constructed on mangrove areas. Through the estimation of landscape metrics for different scenarios (with and without shrimp culture infrastructure), we find that in addition to direct removal of saltmarshes, shrimp aquaculture has significantly modified the spatial patterns of coastal wetlands, retreating wetland borders and fragmenting their patches. These last impacts are mainly related with the development of the linear infrastructure associated with shrimp culture (drainage channels and roads), rather than the construction of the ponds. Present findings and other from similar studies done in Northwest Mexico; allow us to estimate that 60% of shrimp farming in Mexico impacted directly on saltmarshes, contrasting with the 3% of shrimp farms built on mangroves. 相似文献
8.
福建东山岛地质灾害特征与成因初探 总被引：5，自引：5，他引：0
海岛是海上陆地国土和人类开发海洋的远涉基地及前进支点。海岛大幅度地快速增长的开发活动与工程建设使脆弱的海岛生态环境正遭受到严重威胁。东山岛是福建第二大岛,近10年随着水产养殖与育苗、风电建设、环岛公路和房地产开发等海岛利用和开发强度的加大,海岛地质灾害及潜在风险陡增。基于现场调查和遥感影像解译,分析东山岛赋存的地质灾害类型及其分布,初步探究了主要地质灾害的诱因,为更有效地保护和可持续性开发东山岛,制定合理长效规划、防灾与减灾对策提供准确依据,并为福建及周边基岩岛的地质灾害调查与防治提供实测数据参考。 相似文献
9.
《Ocean & Coastal Management》2000,43(7):597-607
Shrimp farming development in southern Sinaloa and its effects on coastal environments were analyzed by municipalities and by region. The study was made on 24 farms that represent 89% of the total farms in the region. This activity grew from 100 to 1820 ha after 14 yr, but there were no serious alterations of the landscape as a consequence of the farm construction, with the exception of those that had invaded lagoon systems. Most of the farms were built on saline, low-productive soils. However, some natural processes in the estuarine systems such as silting and hydrodynamics could have been modified because of the shrimp farm infrastructure (channels, dredging). The characteristics of the activity in the region are similar to those at state and national levels. Most operations are semiintensive systems with white, blue, and brown shrimp as the cultured species. The regional shrimp farms have not developed as much as the ones in other parts of the state, but growth is increasing gradually. We suggest that the development of this activity must be regulated, taking into account characteristics of the estuarine systems, and must incorporate a regional view, including some other interacting activities such as agriculture and fishing, to evaluate its growth potential. 相似文献
10.
论海水养殖的养殖容量 总被引：28，自引：1，他引：28
养殖容量应是一个包含环境、生态和经济等诸多因素的综合概念。养殖容量可定义为：单位水体内在保护环境、节约资源和保证应有效益等各个方面都符合可持续发展要求的最大养殖量。合理地利用养殖容量就是要形成一个结构优化和功能高效的养殖生态系统,使所投入的物质得到反复循环、初级生产力得到多途径利用,从而提高生产效益和养殖效益,避免物质的浪费及自身和环境的污染。从养殖生态系统运转的驱动因素来分析,主要靠太阳辐射直接提供能源的系统,如海带养殖系统、扇贝筏式养殖系统等,可称为自养型或自然营养型养殖系统;主要靠人工投饲来提供能源的系统,如对虾池塘养殖系统、吃食性鱼类网箱养殖系统等,可称为异养型或人工营养型养殖系统。这两类养殖系统在生态学上有很多互补性,它们的复合可提高养殖水体的养殖容量。 相似文献
11.
文章借鉴国内外传统模式以及工厂化模式下水产养殖、对虾养殖成本收益分析指标体系的设立方法和相关研究理论,以山东省为例,于2016—2019年实地采集得到样本数据,对南美白对虾工厂化养殖模式下的成本收益进行分析。结果表明：①2016—2019年山东省工厂化养殖南美白对虾的总成本呈波动上升趋势,其中可变成本远高于固定成本;②在成本结构方面,工厂化养殖模式下固定成本中最大支出项为固定资产折旧,设备维修费近年来增长明显,可变成本中饲料费用、水电煤费、虾苗费用为主要成本项,其中饲料费用占比最大且呈持续上升趋势;③2016—2019年山东省南美白对虾工厂化养殖的净利润稍有减少,尤其在2018年经历了断崖式下滑,4年来成本利润率和销售利润率降低,养殖利润水平、盈利水平均有所下降;④2016—2019年净利润对于价格、饲料费用、水电煤费、苗种费用的敏感性依次由高到低,2018年养殖效益较差的情况下各项敏感系数绝对值均有所增加。 相似文献
12.
以1997年8月中旬和2011年10月中旬对三门湾附近海域开展的海域水质现状调查为依据,分析了近15 a间该海域水体环境氮、磷营养盐的分布现状及变化特征。结果表明:近15 a来,三门湾海域的无机氮和活性磷酸盐含量均成倍增长,水体营养程度由轻度富营养化逐步上升为重度富营养化;从营养结构来看,活性磷酸盐仍为限制性富营养化因子;大量的海水养殖是导致该海域营养盐大幅提高的直接原因。因此,为控制三门湾的富营养化现象进一步加剧,建议适度控制海水养殖规模,调整海水养殖结构,加强对三门湾沿岸排污控制,以获得养殖经济效益和生态环境效益的协调、可持续发展。 相似文献
13.
14.
当前我国池塘养殖多数仍沿用传统的池塘养殖模式, 普遍存在以下问题: 高密度养殖、饵料大量投喂、池塘水质恶化、病害频发等。然而传统的应对方法主要是大量换水, 由此产生的养殖废水直接排放到临近水域, 已导致污染扩散、水环境恶化、水域富营养化等系列问题。为降低池塘养殖面源污染, 确保池塘养殖业健康可持续发展, 本文介绍了目前运用于修复池塘养殖水环境的生物修复主要方法, 包括: 微生物修复法——微生态制剂和固定化微生物、植物修复、动物修复法、生物膜法、几种生物修复技术的综合运用等方法, 展望了生物修复方法在池塘养殖水环境修复方面的应用前景, 认为池塘养殖生物膜修复法因具有良好且稳定的水质改良、节能减排及增产增效等效果而具有广阔的应用推广前景。 相似文献
15.
Luigi Vezzulli Mariapaola Moreno Valentina Marin Elisabetta Pezzati Marco Bartoli Mauro Fabiano 《Estuarine, Coastal and Shelf Science》2008
A variety of pelagic and benthic parameters were measured at an aquaculture farm used for the fattening of Atlantic bluefin tuna (Thunnus thynnus) which is located at an exposed site (700 m from the coast, average bottom depth of 45 m and average current speed of 6 cm s−1) in the Mediterranean Sea. The objective was to test whether modern off-shore tuna fattening industries can exert a sustainable organic waste impact on the receiving environment as has been reported for the offshore culture of more traditional Mediterranean species such as sparids. In the water column, the concentration of phytopigments, organic matter, heterotrophic bacteria and the taxonomic abundance of mesozooplankton (at the species level) were assessed. In the sediment, we assessed the concentration of reduced sulphur pools, phytopigments, organic matter, heterotrophic bacteria and the taxonomic abundance of meiofauna (at the taxa level) and nematodes (at the genus level). For most parameters, we found no substantial differences between farm and control sites. Deviations of farm values from control values, when they occurred, were small and did not indicate any significant impact on either the pelagic and benthic environment. Deviations were more apparent in the benthic compartment where lower redox potential values, higher bacterial production rates and a change in nematode genus composition pointed out to early changes in the sediment's metabolism. In addition, indigenous potential pathogenic bacteria showed higher concentration at the fish farm stations and were a warning of an undesirable event that may become established following aquaculture practice in oligotrophic environments. The overall data from this study provide extensive experimental evidence to support the sustainability of modern offshore farming technology in minimizing the hypertrophic-dystrophic risks associated with the rapidly-expanding tuna-fattening industry in the Mediterranean Sea. 相似文献
16.
Biofloc technology has been applied successfully in the intensive aquaculture of several fish and shrimp species. The growth of heterotrophic microorganisms can be stimulated through adding extra carbon, which reduces the nitrogen level in the water and provides microbial protein to the animals. However, most of the studies and practical applications have been conducted in freshwater and marine environment. This paper focused on brine shrimp Artemia that lives in high salinity environment together with other halophilic or halotolerant microorganisms. The effect of carbon supplementation on Artemia growth, water quality, and microbial diversity of biofl ocs was studied in the closed culture condition without any water exchange. The salinity of the culture medium was 100. A 24-d culture trial was conducted through supplementing sucrose at carbon/nitrogen (C/N) ratio of 5, 15, and 30 (Su5, Su15, and Su30), respectively. The culture without adding sucrose was used as a control. Artemia was fed formulated feed at a feeding ration of 60% recommended feeding level. The results showed that sucrose supplementation at higher C/N ratio (15 and 30) signifi cantly improved the Artemia survival, growth and water quality ( P <0.05). Addition of sucrose at C/N ratio of 15 and 30 significantly increased biofloc volume (BFV)( P <0.05). The Illumina MiSeq sequencing analysis showed that supplementing carbon at C/N ratio of 15 had a better total bacterial diversity and richness, and shaped the microbial composition at genera level. This study should provide information for studying the mechanism of biofloc technology and its application in high salinity culture conditions. 相似文献
17.
Temporal variability in predator presence around a fin fish farm in the Northwestern Mediterranean Sea 
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下载免费PDF全文 Bruno Díaz López 《Marine Ecology》2017,38(1)
Recently, aquaculture has generated worldwide interest as a result of the overexploitation of wild stocks combined with a growing international demand for fish and seafood products. Wild fish attracted to the marine fish farms, together with the presence of the farmed fish, are powerful attractants to predators that normally feed on similar or identical fish stocks in nature. This 9‐year study describes for the first time in Mediterranean waters the temporal variability of mammalian and avian predators in a coastal fin fish farm. In all, 99 months (1062 days during 36 consecutive seasons) were spent in the field. By examining the results of this study, it is clear that species as seagulls, shags, bottlenose dolphins and grey herons (considered to cause economic loss in aquaculture owing to direct predation) interact regularly with the fish farm. Although bottlenose dolphins and grey herons were not the most important of all predator species, predatory interactions with the fish farm occurred with what seems to be increasing regularity. Another result observed is the possible bottlenose dolphins’ attraction caused by the harvesting operations in the fish farm. The fish farm offers an alternative food source for predators; hunting at fish farms usually requires less effort on the part of the predator, and becomes a more attractive option than hunting wild fish over wide ranges. During the period of this study, individually identified dolphins feeding were regularly observed feeding on discarded fish from fish farm workers during harvesting operations, supporting the possibility that some individuals are habituated to this food supply. Based on the evidence presented in this paper, it is recommended that strategies for the management of both the aquaculture industry and marine mammal populations should take the results of this study into consideration. 相似文献
18.
《Ocean & Coastal Management》2006,49(9-10):546-561
Much of Southeast Asia's economic success is based on the under-priced export of valuable natural resources. Nowhere is this more evident than in fisheries—an important commodity in Southeast Asia, with significant export volumes contributing to the foreign exchange earnings of these countries.Existing fisheries and aquaculture policy development have lead to increased export earnings over the last decade, but have also resulted in increased extraction rates and incurred huge costs in terms of decreased local economic productivity and destruction of natural coastal resources. What is worrying is that Southeast Asian governments intend to further stimulate the export of fishery products, in particular shrimp from aquaculture, thereby increasingly threatening both domestic food security and the economic opportunities of local communities.This paper argues that: (1) current fisheries management and development policies are not contributing to domestic food security, are not profitable to the Southeast Asian macro-economy, and are doing much damage to coastal ecosystems and rural poor communities; (2) development of shrimp aquaculture has a negative impact and further expansion of the industry should be halted; (3) the considerable fisheries resources of the region should be used and managed to ensure domestic food security and economic development of the presently marginalized sectors of the population.Five recommendations that will help ensure sustainable use of coastal resources and deliver profits to the countries and communities that depend on these resources are made at the end of the paper. 相似文献
19.
Aquaculture, like terrestrial farming, cannot achieve economic and sustainable production without high performing genetic stocks tailored to the conditions under which they are grown. It is essential, therefore, that aquaculture investment includes genetics and biotechnology to adapt marine livestock to the novel conditions of intensive aquaculture and to the demanding markets into which they are sold. The return on investment in well-structured breeding programmes can be very high, and significant performance and economic gains have been demonstrated in multiple species. Many factors must be considered in designing a genetic improvement programme, including the reproductive biology of the species and the identification of realistic and commercially relevant breeding goals based on the resources and facilities available. This paper reviews the options available to aquaculturists and provides examples of how these are being applied to six aquaculture species in New Zealand: king salmon, hāpuku, kingfish, GreenshellTM mussels, Pacific oysters and pāua (abalone). 相似文献
20.
“渤海湾莱州湾毛虾适宜捕捞期的研究”课题组 《海洋湖沼通报》1992,(4)
渤海湾与莱州湾西部,定置网的主要渔获物种类,挂子网50余种,樯张网40余种。主要捕捞对象是毛虾,其他种类大多都在2％以下。其中占0.1％以上的经济幼鱼、幼虾有鳓、青鳞、斑鰶、黄鲫、鲻、梭鱼、鲈、梅童鱼、小黄鱼、黄姑鱼、银鲳、半滑舌鳎和幼对虾等。毛虾等经济虾类和经济鱼类的主要出现时间,挂子网为7月11日—8月20日;樯张网为7月6日—8月25日。夏一世代毛虾产卵群体的主要死亡时间在8月中、下旬。经济幼鱼和幼对虾,挂子网从6月21日,樯张网从5月21日开始逐日增多,至8月20日以后出现的数量都很少。为合理利用毛虾资源,保护经济幼鱼、幼虾资源,根据调查结果并参看毛虾生殖期等有关文献资料,建议这两个海区的毛虾生产期,春汛挂子网应于6月20日,樯张网于5月20日结束,秋汛应于8月21日开捕为宜。禁渔期,挂子网应由原来的7月1日—8月31日调整为6月21日—8月20日;樯张网由原来的6月10日—8月31日调整为5月21日—8月20日较为合理。 相似文献