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1.
There is growing interest in sustainable intensification of aquaculture production. Yet little economic analysis has been done on farm‐level effects of the economic sustainability of production intensification. Data from 83 shrimp farms (43 in Vietnam and 40 in Thailand) were used to identify (through principal component and cluster analyses) 13 clusters of management practices that reflected various scales of production intensity that ranged from 0–1999 kg/ha/crop to 10,000 kg/ha/crop and above, for both Penaeus monodon and Litopenaeus vannamei in Vietnam and Thailand. The clusters identified reflected sets of management practices that resulted in differing yields despite similarities in stocking densities among some clusters. The enterprise budget analysis developed showed that the more intensively managed clusters outperformed the less intensively managed clusters in economic terms. More intensively managed farm clusters had lower costs per metric ton of shrimp produced and were more profitable. The greater yields of shrimp produced per hectare of land and water resources in more intensively managed shrimp farms spread annual fixed costs across a greater volume of shrimp produced and reduced the cost per metric ton of shrimp. Costs per metric ton of shrimp produced decreased from the lowest to the highest intensity level (from US$10,245 at lowest intensity to US$3484 at highest for P. monodon and from US$24,301 to US$5387 for L. vannamei in Vietnam and from US$8184 at the lowest intensity level to US$3817 at the highest intensity level per metric ton for L. vannamei in Thailand). Costs of pond amendments used in shrimp production were particularly high in Vietnam and largely unwarranted, whereas fixed costs associated with the value of land, production facilities, equipment, and labor were sufficiently high in Thailand so that net returns were negative in the long run. Nevertheless, economic losses in Thailand were less at greater levels of intensification. The study demonstrated a clear value proposition for shrimp farmers to use natural resources (such as land) and other inputs in an efficient manner and supports findings from corresponding research on farm‐level natural resource use efficiency. Additional research that incorporates economic analysis into on‐farm studies of sustainable intensification of aquaculture is needed to provide ongoing guidance related to sustainable management practices for aquaculture.  相似文献   
2.
From May to September 2013, monthly samples were collected from swine in a Vietnamese slaughterhouse for influenza virus isolation and serological testing. A(H1N1)pdm09 viruses and a novel H3N2 originating from reassortment between A(H1N1)pdm09 and novel viruses of the North American triple reassortant lineage were isolated. Serological results showed low seroprevalence for the novel H3N2 virus and higher seroprevalence for A(H1N1)pdm09 viruses. In addition, serology suggested that other swine influenza viruses are also circulating in Vietnamese swine.  相似文献   
3.
火龙果茎段再生体系的建立   总被引:1,自引:0,他引:1  
对火龙果茎段离体培养与植株再生过程进行了研究,建立了火龙果的再生体系。结果表明:愈伤最适诱导培养基为:MS+TDZ 0.4mg/L+KT 0.5mg/L+蔗糖30mg/L+琼脂8.8mg/L;丛生芽增殖最适培养基为:MS+TDZ 0.4mg/L+KT 1.0mg/L+BA 1.0mg/L蔗糖30mg/L+琼脂8.8mg/L;生根最适培养基为:1/2MS+NAA 0.3mg/L蔗糖30mg/L+琼脂8.8mg/L(pH 5.8)。  相似文献   
4.
The potential of informal institutions for sustainable management of marine fisheries was examined. The study is based on both primary data collected through two group discussions and interviews and secondary information, including material related to fishing gear operation and whale worship. It shows that informal institutions, including fisher groups, fishing community norms, fisher's knowledge and whale worship have potential to strengthen institutional, ecological, social and community aspects of sustainable fisheries development. Although these informal institutions are not able to fix completely all the problems faced by formal institutions, they are able to complement and consolidate formal institutions to manage marine fisheries effectively. The findings of this study suggest it is imperative that formal institutions should be improved simultaneously with informal institutions to enhance current management for sustainable marine fisheries development.  相似文献   
5.
中越水稻迁飞性害虫稻飞虱、稻纵卷叶螟发生关系分析   总被引:3,自引:0,他引:3  
中越两国同属东亚季风区,水稻病虫害在发生危害上为一个整体。每年水稻稻飞虱、稻纵卷叶螟(以下简称"两迁"害虫)随着季节和气温变化,在两国间往返迁飞,发生为害,相互影响。研究两国水稻迁飞性害虫发生的关系和影响规律,对于提高监测预警的早期预见性和防控工作的主动性,有效控制其危害具有重要意义。2010年以来,中越两国实施了中越水稻迁飞性害虫监测与防治合作项目,通过连续多年开展交流合作,初步明确了越南"两迁"害虫发生规律。本文简要分析了影响越南"两迁"害虫发生的主要因素,探讨了中越两国水稻"两迁"害虫发生规律的相关性,对提高中国"两迁"害虫中、长期预报能力和综合治理水平发挥了积极作用。  相似文献   
6.
【目的】通过收集社会经济学数据,评估居民和社区对海平面上升的适应能力,评估海平面上升的负面影响及其对策,确定应对海平面上升备用对策。【方法】在越南南定省交水县交善乡选择99户居民,分成3组,采用半问卷调查、面谈、家庭群组讨论、重要人物访谈以及当地居民非正式会谈等方法进行调查。【结果】海平面上升已对当地社区造成了极大的负面影响,如作物产量降低、土地流失、盐碱地面积增加、基础设施损坏等。当地社区和居民已经意识到海平面上升的负面影响,并采取了各种应对方法。改变经济结构、选择适宜的作物品种、把水产养殖地转给家庭、鼓励渔民成立渔业合作社并建立早期预警系统是应对海平面上升的主要对策。【结论】应根据潮汐节律和台风、暴风雨发生等所确定的水面上升规律,采取不同的应对策略和方法,以减少海平面上升造成的破坏和损失。  相似文献   
7.
越南不同龙眼品种品质分析比较(英文)   总被引:1,自引:0,他引:1  
[目的]筛选出适合越南当地生产的龙眼品种。[方法]分别对引种至越南农科院北部山区农林研究所内栽培的5个龙眼品种的果实植物学性状和品种果实性状进行了比较分析。[结果]筛选出了可作为鲜食的优良龙眼品种PMP6,PHS1-1以及可用于加工的优良品种HuongChi。[结论]本研究将对越南北部山区的龙眼生产、育种提供参考。  相似文献   
8.
Processes of globalisation in the conventional food provision system have had widespread negative impacts on small‐scale farmers. Yet, alternative food networks, which are characterised by more sustainable production/consumption practices and fairer trade relations, have increasingly been ‘going global’ and, in the process, have been integrating small‐scale farms in the South. One such high‐value export‐led commodity is certified organic shrimp. International third‐party certification schemes are becoming popular as a tool to verify the intangible attributes of such commodities. Using concepts of multifunctionality and agrarian change, this paper examines the implications of introducing an international environmental certification programme to a site where the ‘peasantry’ has been preserved and has limited integration in the global agro‐food system. Drawing on a case study that examines the first certified organic shrimp production project in Vietnam, this paper concludes that the current movement towards post‐productivism in the global North has potential to keep local farming practices in the global South by justifying the value of peasant‐like production methods through international certification. As a result, the development path of agrarian transition might be reshaped into a form not necessarily pursuing industrialisation. This leads to the new interpretation of pre‐ and post‐productivism beyond the North and South divide.  相似文献   
9.
This paper conducts an analysis of the socioeconomic determinants of Vietnam's cross‐provincial variations in natural disaster vulnerability. The purpose is twofold: (i) to capture disaggregated vulnerability variations normally obscured by national statistics, thereby providing more nuanced insights into Vietnam's vulnerability to natural disasters; and (ii) to take advantage of the fact that the overall political system and key institutional structures to a large extent are constant across Vietnam's provinces, which makes the analysis a novel addition to the many disaster studies based on cross‐national variations. The paper's analysis indicates that much of Vietnam's cross‐provincial variations in natural disaster fatalities and economic costs can be explained by differences in key socioeconomic factors. High provincial rates of inequality, poverty and infant mortality, for instance, appear to drive up natural disaster fatalities. Local adaptation efforts should focus as much on these broader socioeconomic dimensions as they focus on the geophysical susceptibility to natural hazards of individual areas.  相似文献   
10.
Small-scale shrimp-culture is an important livelihood for rural residents in Thua Thien Hue (TTH) province, central Vietnam. However, they are facing the risk of exclusion from the food system due to globalization and trade liberalization. To keep these farmers in modern supply chains, their relationships with other chain actors, foremost the collectors, need to be improved. Thus, this study explores the characteristics and constructs of the relationships between the small-scale shrimp growers and their collectors. Data was based on a survey on 83 small-scale shrimp growers, together with 16 unstructured interviews with growers (10) and collectors (6). It was revealed that the relationships between small-scale shrimp growers and collectors in TTH province are short-term and price-driven and are influenced by the power of collectors. The relationship strength was measured by five intercorrelated constructs including reliability, willingness-to-maintain, desire-fulfilment, negotiation capacity, and discussion capacity. Although some constructs were positively correlated, the strength of the relationships was weak. Both business linkages and social connections affected the grower-collector relationships. Female traders had stronger relationships with collectors than males. Therefore, interventions should be focused on business and social linkages as well as females’ involvement in shrimp trade.  相似文献   
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