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1.
近年来,海水养殖集中、集约化的发展格局,导致局部海区的富营养化及养殖环境自身污染程度加重,严重制约海水池塘养殖产业的可持续发展[1].基于多营养层次的生态养殖模式(IMAT),如虾-贝-藻混养[2]及鱼菜共生循环系统(ARS)[3]等模式可显著提高系统的光能利用率和投入系统总能的转化效率,可促进养殖环境内部物质循环利用...  相似文献   

2.
长期以来,淡水渔业(包括淡水捕捞和淡水养殖)在我国乃至全球渔业(淡/海水捕捞和淡/海水养殖)中有着举足轻重的地位,其产量可达全球渔业总产量32%以上,其中淡水养殖在淡水渔业中占主导地位(78%以上),而鱼类养殖为淡水养殖的主要内容,占淡水养殖总产量的 92 .5%[1-3].随着经济不断发展,人们物质和精神生活不断提升...  相似文献   

3.
大黄鱼(Larimichthys crocea)属鲈形目、石首鱼科、黄鱼属,其肉质细嫩、营养丰富,经济价值高,是我国产量第一的海水养殖鱼类[1-3 ].近年来,随着养殖量的攀升、养殖密度增大、养殖环境的恶化,大黄鱼的病害日趋严重[4-5 ] ,其中以寄生虫病的危害尤为突出[6 ].  相似文献   

4.
正据统计,2017年,广东省海水养殖总面积161690公顷,全省海水养殖总产量3029070吨,全省水产品总产量8335387吨,全省海水养殖总产量占全省水产品总产量的36.34%。本文就近年来广东省海水养殖的情况作出介绍,通过分析存在问题,对未来发展提出针对性的建议。近年来广东省海水养殖规模2012-2015年,全省海水养殖总产量以及全省水产品总产量呈稳中微  相似文献   

5.
海水养殖虾夷扇贝供应链可追溯管理体系的探讨   总被引:4,自引:0,他引:4  
我国是海水贝类养殖大国,根据《中国渔业年鉴2010》 [1]的统计,2009年全国海水贝类总产量达1.120×107 t,占水产品总产量的21.9%.其中,海水贝类养殖产量为1.054×107t,占贝类总产量的95.6%.我国海水贝类无论是养殖规模还是产量均居世界首位. 1996年12月18日,欧盟委员会的97/20/EC号决议生效,该决议列出了双壳软体动物、棘皮动物、被囊动物和海产腹足动物的生产和投放市场方面履行等效条件的第三国清单,中国未被列入该清单中[2].1997年欧盟食品兽医办公室使团对我国水产品企业和水产养殖海域检查后,作出97/368/EC号决议,决定不再从中国进口贝类产品,中国贝类对欧盟的出口藉此终止至今[3].  相似文献   

6.
海水网箱养殖对近岸环境影响的研究进展   总被引:3,自引:0,他引:3  
郭芳  黄小平 《水产科学》2006,25(1):37-41
近年来,我国的海水网箱养殖业发展迅猛,已成为我国渔业新兴产业的生力军。海水网箱养殖系统作为一种高密度、高投饵的人工养殖生态系统,其输出的废物,残饵、代谢及排泄废物等是引发环境问题的主要污染源,再加上网箱养殖区布局不合理,通常设在水交换率较低的内湾,当养殖容量超出了海域的环境容量,就会引发一系列生态环境问题[1]。本文就海水网箱养殖对环境污染及防治的研究进展进行综述,并提出今后的重点研究方向。1养殖区水质污染网箱养殖对浅海生态系统的影响主要表现为养殖水域营养负荷增加[2]。一般来说,鲑鳟鱼类的网箱养殖,饲料中总氮的…  相似文献   

7.
040846 新式零排放海水精养循环系统养殖海水鱼=A novel zero discharge intensive seawater recirculating system for the cul- ture of marine fish[刊,英]/Gelfand L Y, Barak Y,Even-Chen Z…//J.World Aquac.Soc..-2003,34(3).-344 -358 对零排放海水循环系统精养真鲷进行了试验。该系统运行期间无废水和污物排出, 使用两个环形水道、一个空气过滤器、一个沉淀池和一个液基反应器。鱼池放养红罗非鱼(尼罗罗非鱼×奥利亚罗非鱼)密度为16 kg/m3,水体盐度0-20。养殖167 d时投放21 kg/m3真鲷代替罗非鱼,养殖225  相似文献   

8.
我国海水养殖及其可持续发展的对策   总被引:11,自引:0,他引:11  
20世纪以来,由于人口的大量增长和社会经济的快速发展,人们对海产品的需求量大大增加,基础研究成果的不断积累,进一步促进了海水养殖业的迅猛发展,与此同时也带来了水域污染问题。特别是80年代中期以来,我国沿海养殖区赤潮频繁发生,对虾、扇贝等病害严重。笔者就近年来国内外在这方面的研究进展进行综述,以期为我国海水养殖的可持续发展提供理论依据[1]。1 我国海水养殖的现状我国的海水养殖业有着悠久的历史,近50年来发展很快。改革开放20多年来,我国海水养殖业一直处于稳步发展态势:一是养殖产量不断增加面积不断扩大,占世界海水养殖…  相似文献   

9.
正凡纳滨对虾(Litopenaeus vannamei)是我国目前主养的对虾品种之一,根据各地的养殖环境,水产科技工作者创立了多种形式的对虾养殖模式[1-5],但是在目前的各种养殖模式中,主要以单养对虾为主。近年来对虾养殖过程中各种疾病频发,这对对虾的养殖业产生了严重的影响,不利于对虾养殖产业的健康发展[6]。养殖对虾疾病频发的原因之一,在于对虾养殖过程中产生的大量废水直接排放到养殖海域,养殖废水的排放量超出了海水的自净能  相似文献   

10.
天然海洋渔业资源衰退,促使近海增养殖快速发展。随着海水养殖规模不断扩大,集约化程度不断提高,以及受养殖环境污染、布局不合理、管理技术相对落后等诸多因素的影响,养殖鱼类的病害频繁发生,已成为制约海水养殖产业的关键因素[1]。  相似文献   

11.
鱼蚌混养对池塘水质、藻相结构及三角帆蚌生长的影响   总被引:2,自引:1,他引:1  
2012年4月26日—2012年12月12日通过在鲢鳙鱼养殖池塘中放养不同密度的三角帆蚌,研究不同三角帆蚌放养比例对鲢鳙鱼养殖池塘中水质、藻相结构及三角帆蚌生长的影响。实验中,鲢鳙放养比例统一为3∶7,总密度为1.5尾/m3。三角帆蚌放养密度则设置4个水平,分别为单养鲢鳙鱼池塘(0只/m3),低密度三角帆蚌混养池塘(0.8只/m3),中密度三角帆蚌混养池塘(1.0只/m3)和高密度三角帆蚌混养池塘(1.2只/m3)。结果显示,混养三角帆蚌池塘的水化指标(TP、PO4-P、NH3-N、NO2-N和NO3-N)均显著低于单养鱼池塘。中密度三角帆蚌混养池塘除NH3-N和化学需氧量(COD)与低密度三角帆蚌混养池塘无显著差异外,其他各项水化指标均显著低于其他3个池塘,并且极显著低于单养鲢鳙鱼池塘。单养鲢鳙鱼池塘藻类平均密度均极显著高于鱼蚌混养池塘,其中在鱼蚌混养池塘中浮游植物密度与三角帆蚌密度成负相关关系。单养鲢鳙鱼池塘的浮游植物生物量均极显著低于中、高密度鱼蚌混养池塘,并且显著低于低密度混养池塘。浮游植物生物量与三角帆蚌密度成正相关关系,鱼蚌池塘中绿藻和裸藻的生物量在养殖过程中上升显著。低、中密度三角帆蚌混养池塘三角帆蚌存活率均显著高于高密度三角帆蚌混养池塘;低密度混养池塘中蚌湿重、壳长及壳宽相对增长率均为最大,显著高于中、高密度三角帆蚌混养池塘。研究表明,养鱼池塘混养三角帆蚌不仅能改善养殖池塘的水质,还能控制藻类数量,促使绿藻和裸藻等大型藻类的生长,提高养殖水体浮游植物的生物量总量,最终还能有效提高三角帆蚌的存活率及生长率。从改善水质,藻相结构,蚌成活率及生长等指标角度考虑,在鲢鳙鱼养殖池塘中,三角帆蚌最佳放养密度为1.0只/m3。  相似文献   

12.
A mixed integer linear programming model was developed to select constrained optimum combinations of aquacultural production alternatives for limited-resource farmers. The model maximized production of fish and livestock for home consumption and cash income.
Poor farmers without access to credit sources make best use of pond resources by stocking fish and utilizing inorganic fertilizer. Integrated systems require greater levels of capital to cover livestock feed costs. Ponds that cannot be drained are best utilized by stocking a polyculture system of bighead carp ( Aristichthys nobilis ), common carp ( Cyprinus carpio ) and fathead minnows ( Pimephales pro-melas ) while drainable ponds are more efficiently utilized in tilapia production.  相似文献   

13.
Studies were conducted to determine the effect of stocking size and density of prawns in polyculture.
In one experiment, postlarval prawns (av. wt. 0.02 g) were stocked in six 0.02 ha earthen ponds at 35,00O/ha. Two ponds were stocked with tilapia fry (av. wt. 0.14 g) and two were stocked with tilapia fingerlings (av. wt. 30.1 g), each at 10,000/ha. Two control ponds had no tilapia. Tilipia stocking size had no effect on prawn growth. Mean weight of prawns after 70 days of culture ranged from a low of 4.5 g when cultured with tilapia fingerlings to a high of 6.6 when cultured in monoculture. Prawn survival was adversely affected by tilapia fry. Average prawn survival in tilapia fry ponds was 65% compared to 75% and 91%, respectively, in tilapia fingerling and monoculture ponds.
In a second experiment, postlarval prawns were stocked in nine 0.02 ha earthen ponds at 40,000/ ha. Six ponds were stocked with 30 g tilapia fingerlings, three at 5,000/ha and three at 15,000/ha. Three control ponds received prawns only. After 100 days of culture, prawn weight ranged from an average of 15.9 g in monoculture ponds to 11.5 g in polyculture ponds. Survival was highest (93.8%) in low density polyculture ponds. Survival was lowest (85.6%) in prawn monoculture ponds. Tilapia reproduction had a negative impact on shrimp production.  相似文献   

14.
In mountainous Northern Vietnam, traditional pond aquaculture is part of the integrated farming activity contributing to food safety and to income generation for small‐scale farmers of ethnic minorities. Traditional pond management consists of a polyculture of macro‐herbivorous grass carp with 3–5 other fish species that are cultured in small ponds with constant water flow through. The main limitations to production are species‐specific mass mortalities of grass carp, a poor feed base especially for all species but grass carp, and poor water quality. In this study, we compared the traditional pond management to a semi‐intensive pond management that was based on the traditional management system but included changes designed by researchers to increase fish production. The modifications consisted of water inflow control, supplemental fertilization and feeding, and a polyculture dominated by common carp. The changes in management significantly reduced the turbidity and increased oxygen supply, as well as the natural food base within the pond. These changes in pond management provide farmers with the possibility to improve their pond aquaculture scheme and overcome previous limitations.  相似文献   

15.
To analyse the relationships among fish species performance and management procedures, a database was built up with data from 31 fish farms during the period 1976–1987 (1673 observations) and analysed through multivariate statistics (factor analysis). The data include nurseries, grow-out and operational ponds with mono- and polycultures of common carp, Cyprinus carpio, tilapia hybrid, Oreochromis niloticus × O. aureus, silver carp, Hypophthalmichthys molitrix, and mullet, Mugil cephalus. The main conclusions include the following. (1) The highest total yields and best tilapia performances were obtained in polyculture ponds where tilapia was the main species. (2) The best carp performances occurred in grow-out polyculture ponds where carp was the main species. Carp performance was improved in polycultures with mullet and silver carp, irrespective of whether tilapia were present or not. (3) Carp and tilapia yields increased as the nutritional inputs (feed pellets, sorghum pellets, manure), pond size and culture duration increased. The effect of the nutritional input was not linear, but logarithmic. (4) Growth rate of common carp was more affected by total density and stocking size than that of tilapia. Better carp and tilapia growth occurred in grow-out ponds when stocked at large sizes and cultured during short periods, mainly when both species were present. (5) Carp growth varied with the geographical region and size of fish pond, being better in smaller than in larger ponds due to reduced access to natural benthic food in deep ponds.  相似文献   

16.
The effects of different densities of caged Nile tilapia, Oreochromis niloticus, on water quality, phytoplankton populations, prawn, and total pond production were evaluated in freshwater prawn, Macrobrachium rosenbergii, production ponds. The experiment consisted of three treatments with three 0.04‐ha replicates each. All ponds were stocked with graded, nursed juvenile prawn (0.9 ± 0.6 g) at 69,000/ha. Control (CTL) ponds contained only prawns. Low‐density polyculture (LDP) ponds also contained two cages (1 m3; 100 fish/cage) of monosex male tilapia (115.6 ± 22 g), and high‐density polyculture (HDP) ponds had four cages. Total culture period was 106 d for tilapia and 114 d for prawn. Overall mean afternoon pH level was significantly lower (P ≤ 0.05) in polyculture ponds than in CTL ponds but did not differ (P > 0.05) between LDP and HDP. Phytoplankton biovolume was reduced in polyculture treatments. Tilapia in the LDP treatment had significantly higher (P ≤ 0.05) harvest weights than in the HDP treatment. Prawn weights were higher (P ≤ 0.05) in polyculture than prawn monoculture. These data indicate that a caged tilapia/freshwater prawn polyculture system may provide pH control while maximizing pond resources in temperate areas.  相似文献   

17.
Ecuadorian Penaeus vannamei were cultured in dirt ponds (each of approximately 163 m2) at four different stocking densities, i.e. 5 shrimp m−2, 10 shrimp m−2, 15 shrimp m−2 and 20 shrimp m−2. Experiments were carried out over three different periods during the year. Each experiment lasted for 11–14 weeks. No commercial feed was given to the shrimp. The only input to the ponds was about 30 kg of cattle manure per pond per week. Chemical composition of the cattle manure was analyzed. Water quality parameters such as temperature, pH, DO and turbidity were recorded twice daily for each experiment; nutrients (nitrite, nitrate, ammonium and phosphate), water ATP, sediment ATP, H2S and chlorophyll were measured twice weekly for each experiment. Shrimp were sampled either weekly or bi-weekly for body weight measurements.

The results showed a negative correlation between stocking density and growth. Weekly growth ranged from 0·44 to 1·58 g week−1. Survival was over 50% in all treatments and averaged at 70·8%. Under these stocking densities, shrimp production ranged from 4·4 to 18·8 kg ha−1 day−1. The stocking density of 15 shrimps m−2 provides better production than the other stocking densities.

Water quality data did not relate to any shrimp growth. Water nutrient levels in pond discharge water were less than or equal to the nutrients in the incoming water in spite of the weekly addition of cattle manure and did not increase with the addition of cattle manure. No coliform bacteria were detected in any pond water samples through the study period. This indicates digestion of cattle manure in marine shrimp ponds would not pollute the environment with high concentrations of dissolved nutrients.

Thus, a marine shrimp pond can be considered a dissolved nutrient marine treatment plant converting unwanted cattle manure (1841 kg cattle manure ha−1 week−1 in this study) into a valuable commodity — shrimp.  相似文献   


18.
不同鲤养殖模式生物絮团系统中鱼体的生长及水质   总被引:2,自引:2,他引:0  
为了探明不同鲤养殖模式生物絮团系统中鱼体的生长及水质变化情况。采用陆基围隔法,分别设置了鲤单养、鲤+鳙二元混养及鲤+鳙+鲢三元混养3种鲤养殖模式,每种模式设3个重复,测定了鲤不同养殖模式下鱼体的生长及水质参数,实验共进行90 d。结果显示,与单养模式相比,二元混养和三元混养鲤的存活率和鱼体蛋白质效率均显著偏高,而其总饲料系数则显著偏低。3种养殖模式中鲤肌肉的水分和粗脂肪含量相互之间差异均不显著,三元混养模式鲤肌肉的粗蛋白和灰分含量均显著高于单养模式。在3种养殖模式生物絮团系统中,生物絮团形成量与水温之间在19.3~28.5°C范围内呈显著的正相关。整个实验过程中,二元混养和三元混养水体的总氨氮、亚硝酸态氮、总无机氮、正磷酸盐及总悬浮颗粒物含量均低于单养模式,而硝酸态氮、总碱度、有机悬浮颗粒物及叶绿素a含量均高于单养模式,除叶绿素a之外,其余水质参数相互之间差异均不显著。研究表明,与传统的混养系统相似,在生物絮团养殖系统中,符合生物学原则的混养模式同样能够有效发挥养殖系统的生态功能,提高养殖效率。  相似文献   

19.
The culture of the carpet shell clams. Tapes decussatus (L.), a high-priced clam is still a very recent activity. Three common methods of culture, culture park. polyculture ponds and trays inside a tank, were tested to assess which one gave better growth. Mean weights, length and width were recorded in order to determine non-isometrical growth. The highest percentage mean weight gain and specific growth was observed for the carpet shells in the polyculture pond (89 x 10-3 mm day-1 versus 2.2 x 10-3 and 3.3 x 10-3 mm day-1 in the park and the aquaria, respectively). Despite the lower temperatures, water fertility favoured faster growth of phytoplankton, and therefore, of clams in the pond cultured shells. It is concluded that growth in polyculture ponds with fish and shrimps produces the best results and management.  相似文献   

20.
The production performance of genetically improved farmed tilapia (GIFT, Oreochromis niloticus) and freshwater prawn (Macrobrachium rosenbergii) in periphyton‐based systems were studied in farmers' ponds at Mymensingh, Bangladesh. Fifteen ponds (200–300 m2 area and 1.0–1.5 m in depth) were used to compare five stocking ratios in triplicate: 100% GIFT, 75% GIFT plus 25% prawn, 50% GIFT plus 50% prawn, 25% GIFT plus 75% prawn and 100% prawn. Ponds were stocked at a total density of 20 000 GIFT and/or prawn ha?1. Bamboo poles (mean diameter 6.2 cm and 5.5 pole m?2) were posted in pond bottoms vertically as periphyton substrate. Periphyton biomass in terms of dry matter (DM), ash‐free DM and chlorophyll a were significantly higher in ponds stocked with prawn alone than in ponds with different combinations of GIFT and prawn. Survival of GIFT was significantly lower in ponds stocked with 100% GIFT (monoculture) whereas, that of prawn was significantly higher in its monoculture ponds indicating detrimental effects of GIFT on prawn's survival. Individual weight gains for both species were significantly higher in polyculture than in monoculture. The highest total fish and prawn yield (1623 kg GIFT and 30 kg prawn ha?1) over 125–140 days culture period was recorded in ponds with 75% GIFT and 25% prawn followed by 100% GIFT alone (1549 kg ha?1), 50% GIFT plus 50% prawn (1114 kg GIFT and 68 kg prawn ha?1), 25% GIFT plus 75% prawn (574 kg GIFT and 129 kg prawn ha?1) and 100% prawn alone (157 kg ha?1). This combination also gave the highest economic return. Therefore, a stocking ratio of 75% GIFT plus 25% prawn at a total density of 20 000 ha?1 appeared to be the best stocking ratio in terms of fish production as well as economics for a periphyton‐based polyculture system.  相似文献   

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