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罗非鱼是全世界最普遍的养殖鱼类之一,也是我国养殖和出口产业化最成功的外来引进种,我国罗非鱼养殖稳步发展.2016年我国罗非鱼养殖受到恶劣天气和疾病的影响程度与往年基本相似,但罗非鱼仍然是水产养殖者的重要选择.其中广东罗非鱼养殖产量和出口量仍将占全国的40%以上,在中国和世界罗非鱼产业中的地位举足轻重.虽然广东罗非鱼发展较快,但也存在一些亟待解决的问题,如种苗市场混乱、投机行为严重、病害制约、用药不规范、药物残留问题仍然存在等.笔者分析了2016年广东罗非鱼产业发展概况,为罗非鱼产业健康发展提供参考. 相似文献
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黄皮书预警:市场形势复杂,风险增大
11月8日,广西南宁,第七届罗非鱼产业发展论坛发布了《罗非鱼产业发展年度报告黄皮书~2009》。在风险等级里,黄皮书表示产业发展困难,风险较高。这意味着中国罗非鱼产业经过多年的发展,市场已经趋于饱和,发展空间变小,投资风险加大。 相似文献
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自联合国粮农组织(FAO)推广罗非鱼养殖以来,经过40多年的发展。罗非鱼越来越被大多数国家和地区的人民所接受。尤其是近年来国际市场对罗非鱼需求量的不断扩大,拉动了我国罗非鱼产业的发展,我国已成为世界最大的罗非鱼养殖生产国.其中集约化养殖是主要方式。但是在罗非鱼高密度养殖中也存在一些问题,受传统观念“肥水养大鱼”的影响,不少养殖户习惯于向高密度养殖池中过度施肥。使得水质变差难以管理,时常发生大量死鱼以及出口鱼片因环境污染卫生不合格的现象,因此,推广罗非鱼的健康养殖已势在必行。 相似文献
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自联合国粮农组织(FAO)推广罗非鱼养殖以来,经过40多年的发展.罗非鱼越来越被大多数国家和地区的人民所接受。尤其是近年来国际市场对罗非鱼需求量的不断扩大.拉动了我国罗非鱼产业的发展。随着产量逐年增长和出口量飞速增加.我国已成为世界上最大的罗非鱼养殖生产国.其中集约化养殖是主要方式。但是在罗非鱼高密度养殖中也存在一些问题,受传统观念“肥水养大鱼”的影响,不少养殖户习惯于向高密度养殖池中过度施肥,使得水质变差难以管理,时常发生大量死鱼以及出口鱼片因环境污染卫生不合格的现象,因此.推广罗非鱼的健康养殖己势在必行。 相似文献
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<正>近年来,随着我国罗非鱼养殖产业的发展,由品种种质、养殖方式、饲料、环境等因素导致的病害问题呈逐年上升趋势;饲料价格涨幅过快、人力资源成本增加、商品鱼出售价格波动较大,导致罗非鱼养殖经济效益下滑。如何提高罗非鱼养殖品质、减少疾病灾害、降低养殖风险、提高养殖效益是目前罗非鱼养 相似文献
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近几年,我国罗非鱼养殖、加工和出口发展迅速,已经成为世界最大的罗非鱼养殖生产和出口国家。上个世纪90年代中期以来,我国罗非鱼产量逐年增长,1998年~2009年期间,我国罗非鱼总产量平均年增长率为23.1%,我国占世界年生产罗非鱼苗种和成鱼产量的50%左右,排在世界第一位。和其他产业一样,中国罗非鱼产业目前面临“生产规模不断扩大、出口规模不断增加、订单价格逐渐下降、行业利润持续式微”的发展怪圈和困境。中国罗非鱼价格在国际市场上式微,从2008年3美元/千克跌到2009年的2.77美元/千克。 相似文献
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目前中国针对罗非鱼(Oreochroms mossambcus)出口产品的质量安全监测系统尚不完善,建立罗非鱼质量安全评价标准、评估影响罗非鱼食品安全的因素,对于建立罗非鱼安全防控模式具有重要意义.本研究以罗非鱼的质量安全作为研究目标,通过对苗种培育、养殖环境及水产品流通等环节可能产生的风险事件的识别,建立罗非鱼质量风... 相似文献
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Ali Serhan Tarkan Baran Yourtuolu Fitnat Güler Ekmeki Stacey A. Clarke Louisa E. Wood Lorenzo Vilizzi Gordon Copp 《Fisheries Management and Ecology》2020,27(2):123-131
The European Non‐native Species in Aquaculture Risk Analysis Scheme (ENSARS) was used to assess one of the most popular aquaculture species in the world, the striped catfish Pangasianodon hypophthalmus (Sauvage, 1878), in two locations of southern Anatolia (Turkey). The overall mean risk score generated for P. hypophthalmus by the ENSARS Organism module (which assesses the risks of introduction, establishment, dispersal and impact) indicated that the species poses a medium risk under current climatic conditions. All other ENSARS modules rendered scores that indicated a moderately low risk under current climatic conditions. However, the risks of introducing novel diseases and the actual use (e.g. deliberate introduction to the natural habitats or food market) of the species both attracted scores indicating a medium risk. Confidence levels were medium or high for all modules except the Socio‐economic, with low confidence values also attributed to the risks for farming process of the organism, and its overall risk of spread into the wild during farming procedures and to marketing impacts. Recommendations are provided for further use of the ENSARS scheme, especially for a a priori assessment of potential aquaculture species in Turkey, where the sector has been remarkably developing in the last decades. 相似文献
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Ecological footprint for assessment of resource use and development limitations in shrimp and tilapia aquaculture 总被引:3,自引:0,他引:3
We review estimates of the spatial ecosystem support required to run a typical semi-intensive shrimp farm in a coastal mangrove area in Carribean Colombia, and to produce food inputs and process wastes for large-scale industrially managed tilapia cage culture and small-scale, semi-intensive tilapia pond farming in Lake Kariba, Zimbabwe. The tilapia farming is discussed in relation to the pelagic kapenta, Limnothrissa miodon (Boulenger), fishery and to inshore fisheries in the Lake. The results show that a semi-intensive shrimp farm needs a spatial ecosystem support—the ecological footprint—35 to 190 times the surface area of the pond, mainly mangrove area. Based on the analysis, we conclude that shrimp farming in Colombia is already utilizing close to the full support capacity of its coastal environment. In intensive tilapia cage farming, the ecological footprint for feed production is 10 000 times larger than the area of the cages. In contrast, a tilapia pond farm maintained on offals from fisheries, agriculture and households depends very little on external ecosystem areas. As long as there is a direct market for human consumption of all kapenta caught in the Lake, fish cage farming based on fish meal from kapenta would be doubtful from ethical, ecological as well as resource management points of view, even if it was economically feasible. 相似文献
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Community livelihood and patterns of natural resources uses in the shrimp‐farm impacted Mekong Delta
This case study looks at changing livelihood strategies of the coastal population in Soc Trang Province in the Mekong Delta, Vietnam, and their impacts on natural resources. It provides an opportunity not only to document the impact of shrimp farming on coastal livelihood but also to better understand the link between brackish water aquaculture development and natural resource use. The approach includes a socio‐economic survey in six villages of the province focusing on risk strategies and livelihood diversification. Shrimp farming was found to be less risky and more profitable for households and private companies with a higher investment capacity than for poorer households. Households facing a high risk in shrimp farming diversified their aquaculture production, with other high‐value species like mud crab and elongated goby as a coping mechanism. The use of natural resources' collection is shifting from home consumption towards market‐oriented sales of juvenile mud crabs, clams or fish (elongated goby) to supply seed for brackish water aquaculture developments. 相似文献
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Risk sensitivity is an important component of fisher behaviour, yet its impact on fisher decision‐making and utility is poorly understood. Here, we incorporate various forms of risk in a model of location choice by fishing vessels targeting broadbill swordfish, Xiphias gladius, and evaluate the importance of risk sensitivity for predicting location, perceived utility and profit over a fishing season. We consider short‐term, or trip‐level, risk as natural, social or endogenous. Longer‐term, or seasonal, risk includes accumulated profit as a state variable. When considering only short‐term risk, endogenous and social risks are predicted to have the largest impact on profit, while natural risk also is predicted to impact on location choice. When longer‐term (seasonal) risk was considered, the impacts of short‐term (trip‐level) risks on profit were reduced. Model results were somewhat sensitive to assumed input parameters. The model allows users to quantify the extent of risk interaction and the relative sensitivity of perceived utility, location choice and profit. By providing a utility function capturing the fisher decision‐making process, the model provides a platform for the consideration of simultaneous forms of risk under different circumstances. 相似文献
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Atuganile Malambugi Zhenzhen Yu Wenbin Zhu Lanmei Wang Feibiao Song Samwel Mchele Limbu Zaijie Dong 《Aquaculture Research》2020,51(5):1824-1833
Farming of red tilapia is increasing rapidly. However, its commercial farming development is challenged by lack of clear information on genetic basis for skin colour and pigmentation differences due to environmental changes. This study investigated the effects of photoperiod (light:dark, L:D) on the growth and skin colour variation of Malaysian red tilapia. A total of 180 fish weighing 150.48 ± 0.44 g were reared under natural photoperiod (13L:11D, control), prolonged lightness (24L:0D) and prolonged darkness (0L:24D) in three replicates for 78 days. The weight gain of fish cultured under both prolonged light and darkness were significantly higher than fish under natural photoperiod. The tyrosinase level in ventral skin was significantly higher for fish cultured under prolonged darkness condition than in the other two photoperiod regimes. Contrary, the cysteine level in the dorsal skin was significantly higher in the fish cultured under natural photoperiod than in prolonged light and darkness. The relative mRNA expressions of SRY‐related HMG‐Box 10 (sox 10), tyrosine (tyr), tyrosine‐related protein 1 (tyrp‐1) and solute carrier family 7 member 11 (slc7a11) genes were significantly higher in ventral skin of fish under prolonged darkness than the other two photoperiods. This study demonstrates that photoperiod has an impact on melanogenesis and growth of red tilapia. Understanding the effects of photoperiod on genetic basis of red tilapia will help in selective breeding programme of the important economic traits for the development of commercial red tilapia farming. 相似文献
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Edgar Sanchez-Zazueta Francisco Javier Martinez-Cordero 《Aquaculture Economics & Management (Blackwell Science)》2013,17(4):312-327
In Mexico shrimp farming is the most important aquaculture activity. However, its sustainable development has been threatened in recent years by the economic risk associated with low yields caused by outbreaks of viral diseases. A stochastic bioeconomic model was developed to analyze the economics of farm management adjustments as a response to disease risks, using pond-level data from a farm operating in the State of Sinaloa, Mexico, during the period 2001–2005. The data base analyzed included different combinations of stocking density (in the range 6–30 PL/m2) and culture time (from 12 to 31 weeks), which allows for wider application of the simulation results, even at the industry level. Results from this study indicate that operating costs would increase by 33% if the farmer would choose to market product directly. Scenarios with lower stocking densities and intermediate culture times generated the highest probabilities 6–9 PL/m2 16–19 weeks (76%/100%/70%), and 10–14 PL/m2 20–24 weeks (72%/99%) of achieving superior economic performance, as demonstrated by achieving the target reference point of 35% operating profit margin ratio. The study reinforces the value of the current trends in Sinaloa to reduce stocking density as a good management practice to decrease the impact of diseases. This study also provides important additional knowledge on the specific economic results and risks associated with the combination of these two management variables at different levels. 相似文献
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Multi-criteria evaluation approach to GIS-based land-suitability classification for tilapia farming in Bangladesh 总被引:1,自引:0,他引:1
M. Shahadat Hossain Sayedur Rahman Chowdhury Nani Gopal Das M. Moshiur Rahaman 《Aquaculture International》2007,15(6):425-443
Site selection is a key factor in any aquaculture operation, because it affects both success and sustainability. It can, moreover,
solve conflicts between different activities, making rational use of the land. This study was conducted to identify suitable
sites for development of Nile tilapia (Oreochromis niloticus) farming in Sitakunda Upazila (sub-district), Bangladesh, using GIS-based multi-criteria evaluation of water and soil quality,
topography, infrastructure and socio-economic factors. ASTER image and eighteen thematic layers were analyzed using ENVI and
ArcView software to identify the suitable areas for tilapia farm development. A constraint layer was used to exclude areas
from suitability maps that cannot be allowed to implement tilapia farming. A series of GIS models were developed to identify
and prioritize the most suitable areas for tilapia farming. The output of the model clearly indicates the location and extent
of tilapia farming areas on different suitability scales, i.e. most suitable (7,744 ha), moderately suitable (2,479 ha), and
not suitable (838 ha). Model outputs were assessed against field verification data, and were consistent. Because existing
aquaculture covers only 1,540 ha of land in the study area, the potential for expanding tilapia farms should take into consideration
socio-political and environmental issues. The results are encouraging in terms of tilapia culture development and suggest
that grassland–agriculture areas could be used for sustainable development of tilapia farming to diversify the economic activities
of rural communities. 相似文献
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为了解渤海中部海域沉积物中重金属的污染状况,于2013年8月采集了渤海中部海域34个站点的表层沉积物,检测了Pb、Cd、Hg、Cu、Zn和As 6种重金属的含量,分析了Pb、Cd、Cu和Zn 4种重金属的空间分布特征,采用污染指数法和潜在生态风险评价法对其表层沉积物重金属污染状况进行评价。结果显示,渤海中部海域表层沉积物重金属含量较低,符合海洋沉积物质量(GB 18668-2002)Ⅰ类标准的要求。表层沉积物重金属的空间分布总体呈现由近岸向中心海域降低的趋势。Cu、Zn和Pb含量空间变化趋势比较明显,靠近渤海湾海域重金属含量高,离岸距离越远,重金属含量逐渐降低。Cd含量在靠近黄河入海海域最高,呈现自高值区向东西两边海域减小的趋势。各个站位的重金属单因子污染程度较轻,单因子污染系数均值大小顺序为PbCuZnAsCdHg;重金属综合污染指数都小于5,表现为低污染水平。除1号站位的Hg单因子潜在生态风险系数为54.44之外,其他站位表层沉积物Hg、As、Cu、Zn、Pb和Cd的单因子潜在生态风险系数Eir小于40,范围为0.39~38.80,风险程度由高到低依次为Hg、Cd、As、Pb、Cu和Zn;其综合潜在生态风险系数小于150,范围为16.39~79.57。其中,1号站位综合潜在生态风险系数最高达到79.57。研究表明,此海域属于低潜在生态风险水平,风险指数高值区出现在唐山大清河口海域。 相似文献
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This study builds a long-term bioeconomic model for multi-generational tilapia farming in the coastal region of Ecuador, where associative semi-intensive tilapia culture projects have been implemented. Survival, weight and length curves were calibrated, and feed consumption and feed conversion rate curves were constructed. Revenues, costs and investments were also estimated. It was found that operational net present values per batch are maximized when fishes are harvested on approximately day 300 after stocking, in contrast to 180 days, which is the actual time of harvest at present. Thus, culture performance can be improved significantly if recommendations arising from the model are followed. Finally, sensitivity analysis of the model demonstrated that tilapia cultures can withstand unfavorable variations in critical parameters. 相似文献