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Angler apps as a source of recreational fisheries data: opportunities,challenges and proposed standards 
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下载免费PDF全文 Recreational fisheries surveys are limited in time and place in many countries. This lack of data limits scientific understanding and sustainable management. Smartphone applications (apps) allow anglers to record the details of their fishing trips and catches. In this study, we describe the opportunities and challenges associated with angler apps as a source of recreational fisheries data, and propose minimum standards for data collection via angler apps. Angler apps are a potentially valuable source of conventional and novel data that are both frequent and extensive, and an opportunity to engage anglers through data sharing and citizen science. Realizing this potential requires that we address significant challenges related to angler recruitment and retention, data quality and bias, and integration with existing fisheries programmes. We propose solutions to each of these challenges. Given that the angler app market is diverse, competitive and unpredictable, we emphasize minimum standards for data collection as a way to ensure large and reliable data sets that can be compared and integrated across apps. These standards relate to trips and catches, and angler demographics and behaviour, and should be supported through consultation and research. Angler apps have the potential to fundamentally change how anglers interact with the resource and with management. 相似文献
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为了探究鱼类不同组织中矿物元素的含量，实验以养殖黄颡鱼为对象，采用电感耦合等离子体质谱法测定了黄颡鱼18个组织(心脏、肝脏、脑、脾脏、肾脏、肌肉、脂肪、前肠、中后肠、眼睛、鳃、尾鳍、鱼鳔、骨骼、胃、皮肤、血液、全鱼)中7种矿物元素(Ca、Mg、Zn、Fe、Cu、Mn和Se)的含量与分布。结果显示，Ca在骨骼、鳃、尾鳍和肌肉中占比较高，在尾鳍和骨骼中含量最高，在脂肪组织中含量最低；Mg在骨骼和肌肉中占比较高，在骨骼和尾鳍中含量最高，在眼睛中含量最低；Zn在骨骼、肌肉、皮肤和眼睛中占比较高，在眼睛中含量最高，在脂肪组织中含量最低；Fe在骨骼、血液和肌肉中占比较高，在血液中含量最高，在脂肪组织中含量最低；Cu在骨骼、肌肉和肝脏中占比较高，在肾脏和肝脏中含量较高，而在脂肪和眼睛中含量最低；Mn在骨骼和肌肉中占比较高，在骨骼和尾鳍中含量较高，在眼睛和脂肪中含量较低；Se在肌肉、骨骼、皮肤和肝脏中占比较高，在脾脏、肝脏、肾脏和前肠中含量较高，在肌肉和脂肪中含量较低。研究表明，黄颡鱼体内含有丰富的矿物元素(Ca、Mg、Zn、Fe、Cu、Mn、Se)，而且在不同组织中具有不同的分布特征。研究采用ICP... 相似文献
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Abstract Immigration of catadromous anguillid eels into fresh water can be impeded by barriers such as barrages, weirs and dams. The uses of passes and trap-and-transport systems to enhance recruitment are reviewed. Pre-construction studies of the needs for passes and traps are discussed in relation to key biological and hydraulic management criteria. Recommendations for pass and trap designs and placement are made in the context of site-specific biotic and abiotic factors. Reference is made to experience gained from eel passes and trapping systems in use throughout the world, and to experimental and pre-and post-construction monitoring studies. Practical recommendations are made for the design and use of eel passes and traps for monitoring studies and for trap-and-transport stocking. 相似文献
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采用聚合酶链式反应-变性梯度凝胶电泳(PCR-DGGE)和荧光定量-聚合酶链式反应(Q-PCR)技术分析高体重(high weight,HW)和低体重(low weight,LW)斑点叉尾(鮰)(Ietalurus punetaus)皮肤、鳃和胃肠道菌群多样性,为斑点叉尾(鮰)微生态研究及筛选斑点叉尾(鮰)源益生菌提供理论依据.结果显示,斑点叉尾(鮰)菌群丰富度由低到高依次为鳃、皮肤、前肠、后肠和胃.肠杆菌科(Enterobacteriaceae)和气单胞菌属(Aeromonas)是皮肤的优势菌群;肠杆菌科(Enterobacteriaceae)、气单胞菌属(Aeromonas)和肠球菌属(Enterococeus)是水体、鳃和胃的优势菌群;肠杆菌科(Enterobacteriaceae)、拟杆菌属(Bacteroidetes)、气单胞菌属Aeromonas)和酵母菌属(Saccharomyces)是肠道的优势菌群.HW斑点叉尾(鮰)鳃菌群的香农多样性指数、均匀度和丰富度及前肠菌群的丰富度显著高于LW斑点叉尾(鮰)(P＜0.05).皮肤的黄杆菌属(Flavobacterium),胃的肠杆菌科(Enterobacteriaceae),前肠的拟杆菌属(Bacteroidetes)和双歧杆菌属(Bfidobacterium及后肠的拟杆菌属(Bacteroidetes)、双歧杆菌属(Bifidobacterium)和酵母菌属(Saccharo-myces)的拷贝数分别是101 97、107.69、106.19、103.83、106.13、103.92和104 26,均显著高于LW斑点叉尾(鮰)(P＜0.05).结果表明,斑点叉尾(鮰)皮肤、鳃、胃肠道均形成独特的菌群结构,LW和HW斑点叉尾(鮰)菌群结构存在明显差异,HW斑点叉尾(鮰)菌群多样性增加. 相似文献
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Aquatic food security: insights into challenges and solutions from an analysis of interactions between fisheries,aquaculture, food safety,human health,fish and human welfare,economy and environment 下载免费PDF全文
下载免费PDF全文 Simon Jennings Grant D Stentiford Ana M Leocadio Keith R Jeffery Julian D Metcalfe Ioanna Katsiadaki Neil A Auchterlonie Stephen C Mangi John K Pinnegar Tim Ellis Edmund J Peeler Tiziana Luisetti Craig Baker‐Austin Mary Brown Thomas L Catchpole Fiona J Clyne Stephen R Dye Nathan J Edmonds Kieran Hyder Janette Lee David N Lees Owen C Morgan Carl M O'Brien Birgit Oidtmann Paulette E Posen Ana Ribeiro Santos Nick G H Taylor Andrew D Turner Bryony L Townhill David W Verner‐Jeffreys 《Fish and Fisheries》2016,17(4):893-938
Fisheries and aquaculture production, imports, exports and equitability of distribution determine the supply of aquatic food to people. Aquatic food security is achieved when a food supply is sufficient, safe, sustainable, shockproof and sound: sufficient, to meet needs and preferences of people; safe, to provide nutritional benefit while posing minimal health risks; sustainable, to provide food now and for future generations; shock‐proof, to provide resilience to shocks in production systems and supply chains; and sound, to meet legal and ethical standards for welfare of animals, people and environment. Here, we present an integrated assessment of these elements of the aquatic food system in the United Kingdom, a system linked to dynamic global networks of producers, processors and markets. Our assessment addresses sufficiency of supply from aquaculture, fisheries and trade; safety of supply given biological, chemical and radiation hazards; social, economic and environmental sustainability of production systems and supply chains; system resilience to social, economic and environmental shocks; welfare of fish, people and environment; and the authenticity of food. Conventionally, these aspects of the food system are not assessed collectively, so information supporting our assessment is widely dispersed. Our assessment reveals trade‐offs and challenges in the food system that are easily overlooked in sectoral analyses of fisheries, aquaculture, health, medicine, human and fish welfare, safety and environment. We highlight potential benefits of an integrated, systematic and ongoing process to assess security of the aquatic food system and to predict impacts of social, economic and environmental change on food supply and demand. 相似文献
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水域生态牧场从水域生态学和景观生态学角度出发，高度重视生态系统的整体性和连通性，是拓展渔业空间、推动业态融合发展的重要场景。为了实现我国渔业的健康高质量发展，生态经济和数字经济将共同驱动水域生态牧场的模式创新和产业发展。本文详述了水域生态牧场建设的必要性、发展理念和应对策略，阐述了数字赋能从关键技术、无人装备和智能管理三方面助力水域生态牧场的体系化、数字化建设，提出了四场联动、陆海贯通、牧养互动和业态融合的发展模式，以期为更好地利用数字技术，科学、规范建设水域生态牧场提供参考。 相似文献
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“十一五”以来,我国农垦加快体制机制改革、结构调整和经济增长方式的转变的步伐,参与市场竞争,努力提升企业和产品竞争力,经济社会事业发展较快,对国家的贡献提升,职工收入、生活质量明显提高和改善,示范引领作用不断增强。本文针对农垦体制机制创新进展滞缓,战略定位与发展方向不明,经济增长方式转变和结构调整缺乏资本、人才、技术的支撑,没有处理好改革、发展、稳定、民生的关系,投资匮乏,发展后劲不足,人才短缺和劳动力素质低下的现状,提出在未来农垦体制机制创新中要特别关注改革方向、目标设定与评估,改革要在现行法律法规的框架内运作,改革时机的选择,处理好改革发展稳定与民生的关系,调整好内部利益分配关系,自觉融入区域经济,与地方协同发展等问题。为了促进农垦的发展,建议国家加大对农垦体制机制创新、现代农业建设、国有农场土地资源的保护、社会保障体系的完善等财政和政策的支持力度。 相似文献
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Abstract. Severe melanotic liver and visceral fibroses in bluegill associated with infections of plerocercoids of Proteocephalus sp. and metacercariae of the digenean Posthodiplostomum minimum , were studied by light and transmission electron microscopy. Fibrosis was most evident in bluegill carrying heavy worm burdens. Tubular and multilocular melanotic and non-melanotic cysts were formed of concentric layers of non-cellular eosinophilic connective tissue surrounding central spaces containing basophilic material. Moribund and deteriorating plerocercoids and metacercariae were surrounded by, and sometimes invested with, fibrous tissue. Living plerocercoids in the liver were surrounded by necrotic and compressed hepatocyte zones. Fibro-blasts, epithelioid cells and eosinophilic granulocytes were common in compressed cell zones. Intrahepatic fibrotic cysts were surrounded by granulomatous zones. Parenchyma in fibrotic livers showed increased numbers of macrophages, melano-macrophage centres and engorged blood vessels with thickened walls. Histochemical tests for lipofuscin and haemosiderin were strongly positive in melanotic liver tissue. Ultrastructural changes in hepatocytes adjacent to fibrotic cysts and epithelioid zones included intranuclear lipid and glycogen inclusions, chromatin alterations and mitochrondrial degeneration. Bile canaliculi, sinusoids and perisinusoidal spaces showed reduced micro villarsurfacesand a decrease in luminar diameter. Degenerating hepatocytes contained phagolysosomes and myelin bodies. 相似文献
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在全球气候变化和人类活动的干扰下,海洋生物多样性及其可持续利用受到了严重威胁,对海洋生物多样性的研究也逐渐成为各国学者当前的研究热点。基于Web of Science核心合集的文献数据,利用文献计量学和知识图谱方法,对其发文量的增长趋势、来源期刊和区域分布以及学科类别等进行分析,并基于合作网络、关键词共现的知识图谱及突变检测等方法,探究全球海洋生物多样性的研究进展及其热点。结果显示,研究文献的年度发文量总体上呈动态递增趋势,且文献的科研影响力及国际关注度非常高;发文量较多的作者、机构间均形成了密切而稳定的合作关系,Miloslavich P、Danovaro R和Mouillot D等为该领域的核心作者,以詹姆斯库克大学、塔斯马尼亚大学及不列颠哥伦比亚大学等机构为核心的机构间建立了广泛的合作关系,主要涉及的学科类别为生态学、生物多样性保护、海洋淡水生物学及环境科学等。当前,全球海洋生物多样性的研究热点主要有5个方向:(1)人类活动和气候变化对海洋生物多样性的影响;(2)海洋生物多样性保护及其可持续利用;(3)国家管辖范围外海洋保护区及具有重要生态或生物学意义的海域生物多样性研究;(4)海洋生物多样性和生态系统变化的观测及其评价;(5)海洋遗传多样性和海洋生物多样性的地理变异研究。 相似文献
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Evaluation of Bioelectric Impedance to Predict Carcass Yield, Carcass Composition, and Fillet Composition in Farm-Raised Catfish 总被引：1，自引：0，他引：1
Abstract.— Bioelectric impedance analysis (BIA) was evaluated as a method for predicting carcass yield, fat, and moisture in live channel catfish, Ictalurus punctatus (N = 20), and fat and moisture in fillets from channel catfish ( N = 20) and channel catfish female × blue catfish male, I. furcatus , hybrids ( N = 20). Fish were cultured in ponds, fed a commercial catfish diet (28% protein), and harvested at market weight (450 g-900 g, ∼19 months post-hatch). Live channel catfish were tranquilized, weighed, and sexed. Resistance and reactance were measured with a four-terminal impedance analyzer. Fish were then deheaded, eviscerated, weighed, and carcass yield was calculated. Fillets from channel catfish and channel catfish × blue catfish hybrids were measured for weight, resistance, and reactance. Carcasses and fillets were ground and fat and moisture were determined by chemical analysis. Regression models including total weight, resistance, and reactance as independent variables explained 71%, 75%, and 65% of the variation in carcass yield, fat, and moisture, respectively, in live fish. Regression models with fillet weight, resistance, and reactance as independent variables explained 62% and 41% of the variation in fillet fat and moisture, respectively, in channel catfish, and 53% and 58% of the variation in fillet fat and moisture, respectively, in channel catfish × blue catfish hybrids. Models including resistance and reactance explained significantly more variation in the traits measured than did models containing only whole weight as an independent variable. Improvements in prediction accuracy will be needed to make BIA a useful tool for predicting carcass yield, carcass composition, and fillet composition in farm-raised catfish. 相似文献
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贝类壳色常呈现出多态性,壳色可以作为优良性状的标记色,用于贝类良种选育研究。为了探究青蛤壳色性状与其生长和营养成分之间的关系,本研究对青蛤不同壳色个体的生长指标及营养组分进行了测定分析。结果显示,青蛤紫壳个体(整体)的湿重、壳长、水管和鳃组织湿重占比显著高于白壳个体(p＜0.05),青蛤紫壳个体(整体)的壳宽和外套膜组织湿重占比极显著高于白壳个体(p＜0.01)。青蛤紫壳个体可食部分的粗脂肪和粗蛋白含量极显著高于白壳个体(p＜0.01)。紫/白壳个体的必需氨基酸与总氨基酸比值分别为37.46%和37.02%,且紫壳个体显著高于白壳个体(p＜0.05);必需氨基酸与非必需氨基酸比值分别为67.72%和66.60%,且紫壳个体显著高于白壳个体(p＜0.05),表明紫壳个体氨基酸平衡效果优于白壳个体,且均属于优质蛋白。紫/白壳个体的单不饱和脂肪酸主要以棕榈酸为主,分别占可食部分脂肪酸总量的9.97%和9.85%,多不饱和脂肪酸主要以EPA和DHA为主,其中EPA分别占脂肪酸总量的6.64%和6.54%,DHA分别占脂肪酸总量的8.00%和8.51%。研究表明,紫/白壳个体间在生长和营养上均存在一定差异,且紫壳性状与其生长和营养存在一定正向关联关系,为利用紫壳性状作为遗传标记进行青蛤良种选育提供理论依据。 相似文献
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使用mtDNA作为分子标记,基于1022 bp和1322 bp左右的部分序列分析刀鲚(Coilia nasus)、湖鲚(C.nasus taihuensis)、七丝鲚(C.grayii)及凤鲚(C.mystus)成鱼之间的遗传关系。结果显示,刀鲚和湖鲚间的遗传距离分别为0.0036±0.0008和0.0038±0.0008,凤鲚与刀鲚、湖鲚的遗传距离分别为0.1215±0.0111、0.1228±0.0111(Cyt b)和0.1075±0.0108、0.1067±0.0107(D-loop),七丝鲚与刀鲚、湖鲚的遗传距离分别为0.0342±0.0056、0.0351±0.0057(Cyt b)和0.0527±0.0069、0.0529±0.0070(D-loop),七丝鲚和凤鲚间的遗传距离分别为0.1158±0.0111和0.1123±0.0111。用Kimura双参数模型构建的2种序列的NJ分子系统树均显示,湖鲚和刀鲚不能形成独立的分支,而是混合聚在一起形成1个分支;七丝鲚和凤鲚则形成另外2个分支。首先根据采样点不同可初步断定未知仔幼鱼为刀鲚,稚鱼为湖鲚,而后对未知种仔幼鱼、稚鱼和刀、凤鲚鱼卵的2种序列的分析发现,不同采集点内部的这些早期生活个体间的遗传距离分别为0.0024~0.0032和0.0025~0.0082。在Kimura双参数模型构建的NJ分子系统树中,未知种仔幼鱼、稚鱼、刀鲚鱼卵与刀鲚、湖鲚聚为一类,凤鲚鱼卵与凤鲚聚为一支。由此可见,Cyt b基因序列和D-loop序列作为分子标记,虽然可以区分刀鲚、凤鲚以及七丝鲚的仔幼、稚鱼及鱼卵,但不能有效区分湖鲚和刀鲚的早期生活个体。 相似文献
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壳金长牡蛎自交和杂交家系生长与存活比较 总被引：2，自引：2，他引：0
选择具有生长优势的长牡蛎(Crassostrea gigas)G2(A)家系及具有明显生长和存活优势的G19(B)和G28(C)家系进行完全双列杂交,得到包括3个自交组(AA、BB、CC)和6个杂交组(AB、AC、BA、BC、CA、CB)共9个壳金长牡蛎实验组,分析各实验组在幼虫期及稚贝期不同日龄的各生长指标和存活性能,并评估了杂交组的杂种优势。结果表明,在整个培育阶段,大多数杂交组在不同生长时期均表现出较高的生长和存活性能,其中,浮游幼虫期5日龄,所有杂交组的壳高和壳长均显著大于自交组(P0.05);10日龄后,杂交组CB、BC和AC的壳高显著大于相应的自交组(P0.05),杂种优势明显;稚贝期85和130日龄,杂交组CB的壳高性能大于其他实验组。浮游幼虫期10日龄,CB组存活率显著大于AA、CA组(P0.05);稚贝期85日龄后,杂交组AC、CA和CB的存活率杂种优势逐渐增大;190日龄,杂交组AC、BC与自交组AA、CC之间存活率差异显著(P0.05)。研究结果为壳金长牡蛎新品种的培育及杂种优势的充分利用奠定了重要基础。 相似文献
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采取L49(78)安排7水平Ca2+、Mg2+、盐度正交试验,开展60d凡纳滨对虾养殖试验,通过比较凡纳滨对虾成活率、日均增长值、日均增重量及鲜味氨基酸含量,分析养殖水体中Ca2+、Mg2+、盐度三因子对凡纳滨对虾存活、生长及虾体风味的影响;采取L8(27)安排2水平Ca2+、Mg2+、盐度正交试验,分析养殖水体中Ca2+、Mg2+、盐度三因子间交互作用对凡纳滨对虾存活、生长及虾体风味的影响。结果表明:水体中Ca2+、Mg2+、盐度对成活率和虾体鲜味氨基酸都有显著影响(P<0.05),Ca2+、Mg2+对凡纳滨对虾生长具有显著影响(P<0.05),其中Mg2+对成活率影响最大,Ca2+对生长影响最大,而鲜味氨基酸受盐度影响最大。Ca2+浓度为100mg/L和400mg/L,Mg2+为1200mg/L,盐度为10时,成活率最高;Ca2+≥200mg/L与Mg2+≥300mg/L时,生长速度无明显变化,Ca2+浓度为100mg/L,Mg2+浓度为150mg/L,盐度为10~20时,体长和体质量增加最快;Ca2+、Mg2+含量与盐度越高,鲜味氨基酸含量越高,Ca2+浓度为400mg/L,Mg2+浓度为750mg/L,盐度为35和20时,风味氨基酸含量最高;低盐、低钙、低镁水体显著降低了凡纳滨对虾的生长存活;Ca2+与Mg2+对成活率及体质量日均增长具有显著的交互作用影响,Ca2+与盐度对成活率具有显著的交互作用影响,Mg2+与盐度对各试验指标均没有显著影响。 相似文献
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为探究福建中部近海鱼类生态类群组成的季节变化,采用非线性多维标度(NMDS)和相似性检验(ANOSIM)方法,依据2009年冬季、2010年春季和夏季于福建中部近海3个航次的海洋综合调查资料,对该海域鱼类的种类组成和生态类群结构进行分析。结果显示,冬季出现鱼类40种,生态类群以暖水种为主,但暖温种比例为3个季节中最高(30%),且暖温种占该季鱼类总质量和总尾数比例分别为17.65%和16.96%。春季出现鱼类39种,生态类群以暖水种为主,分别占该季节鱼类总质量和总尾数的86.48%和94.52%。夏季出现鱼类61种,暖水种占绝对优势(56种),分别占该季鱼类总质量和总尾数的97.17%和99.35%。受浙闽沿岸流和台湾海峡暖流的交替影响,从冬季到夏季物种更替率逐渐升高,暖水种种类数和数量密度不断上升,并伴随着河口种消失、外海种出现。此现象与冷、暖水团交替影响这一海域时,鱼类进行相应的产卵、索饵及越冬洄游等有关。研究表明,福建中部近海鱼类生态类群和种类组成的季节变化可能由水团不断变化所导致。 相似文献
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Over the past decade, the sustainability of seafood production has improved and is cause for ocean optimism. In an attempt for recognition of ongoing efforts, many producers and food retailers now claim products are ‘sustainable’. What exactly does this mean and could we limit further improvement using this claim? Here, we discuss the sustainable/sustainability dichotomy, and the problem of communicating continual improvement in terms of grand and absolute claims – that is ‘We sell 100% sustainable product.’ We believe a statement like this risks short selling the challenges at hand and removes necessary and ongoing incentives for learning, improving and innovating. We argue the best path for producers and retailers is to demonstrate and communicate the concrete actions and achievements being made towards a more resilient and healthy food system today and for the future. This requires moving away from the current practice of calling products sustainable, and to instead work towards continually improving the sustainability of the products. Focusing on measuring the impact of our actions generates a wealth of substance and establishes a direction of travel towards seafood of greater sustainability and we believe this will help educate, inform and inspire consumers to make good choices for their own and future generations benefit. In this study, ‘seafood’ will refer to both farmed and wild seafood products, and ‘sustainability’ refers to the behavior that drives economic, environmental and ethical progress towards ensuring seafood availability ‘meet(s) the needs of the present without compromising the ability of future generations to meet their own needs’. 相似文献
19.
Concurrent rice‐shrimp‐crab farming systems in the Mekong Delta: Are conditions (sub) optimal for crop production and survival? 下载免费PDF全文
下载免费PDF全文 Catherine Leigh Le Huu Hiep Ben Stewart‐Koster Duong Minh Vien Jason Condon Nguyen Van Sang Jesmond Sammut Michele Astrid Burford 《Aquaculture Research》2017,48(10):5251-5262
The Mekong Delta is the most important rice‐ and shrimp‐producing region for food and economic security in Vietnam. Rice‐shrimp farming is practised where salinity fluctuates substantially between wet and dry seasons. Research points to several potential risk factors for rotational systems, but how these link directly to both rice and shrimp production remains poorly quantified for systems that stock and harvest animals year‐round. We examined water and soil quality of 18 rice‐shrimp‐crab ponds, in which shrimp and crab are grown in both wet and dry seasons, in the Cà Mau Province of Vietnam. Multiple lines of evidence indicated that environmental conditions experienced by both rice and shrimp were suboptimal and contributed to low yields and survival. Year‐round cropping of shrimp and crab was associated with sustained suboptimal salinity, intensified by drought, for the wet‐season cultivation of rice. Although rice seedlings were sown in all 18 ponds, only three had a harvestable crop. Low shrimp production and survival was associated with sustained suboptimal water temperatures (too high), salinity (too high in the dry season and too low in the wet season) and dissolved oxygen concentrations (too low). Food availability and quality may also have affected shrimp production. Improving productivity of rice‐shrimp‐crab ponds in the study region may require (1) separation of rice and shrimp crops and improving efficiency of soil washing practices such that salinity conditions are more suitable for each when grown, and (2) management intervention to increase oxygenation of water, and the availability and quality of food for shrimp. 相似文献
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Daercy Maria Monteiro Rezende Ayroza Marcos Gomes Nogueira Luiz Marques da Silva Ayroza Edmir Daniel Carvalho Antonio Sergio Ferraudo Antonio Fernando Monteiro Camargo 《Journal of the World Aquaculture Society》2013,44(6):814-825
The influence of tilapia cages on limnological characteristics of the Chavantes Reservoir, Paranapanema River, Brazil, was investigated in March and June 2007. Principal components analysis was used to compare the transparency; dissolved oxygen; temperature; total organic nitrogen, phosphorus, and dissolved solids; chlorophyll a and electrical conductivity of fish farm 1 (239.3 m.t.), 2 (461.5 m.t.) and areas without cages, in the lacustrine and river‐reservoir transition regions. The variables differentiated the regions and areas with and without cages. In March, in the lacustrine region, there was a thermal and chemical stratification, and in the transition region, there was a temperature and oxygen reduction gradient between the surface and bottom that was also observed in June in fish farm 1. The higher transparency confirmed the increased light penetration in the lacustrine region. In the transition region, there were higher turbidity, total dissolved solid, and conductivity values that are likely related to allochthonous material flow and transport. In fish farms, lower oxygen and pH values indicate intense decomposition and respiration. The generally higher total dissolved solid and nutrient values, turbidity, and conductivity and the lower transparency in one or both fish farms indicate their contribution to eutrophication, demonstrating the need for careful monitoring. 相似文献