网箱养殖箱体内外的水质变化

从网箱养殖过程中向水体输入废物的角度,对影响箱体内外水质变化的因子进行分析,探讨了网箱养殖箱体内外的水质变化及其影响,并为网箱养殖业的健康的可持续发展提出一些防治对策。     

网箱养殖箱体内外的水质变他

从网箱养殖过程中向水体输入废物的角度，对影响箱体内外水质变化的因子进行分析．探讨了网箱养殖箱体内外的水质变化及其影响。并为网箱养殖业的健康可持续发展提出一些对策。     

网箱养殖水下监控系统设计的技术问题及对策

随着开发海洋、江河与湖泊科学事业的发展,水下工程的规模越来越大,渔业生产也不例外,尤其是近年来海、淡水网箱养殖的快速发展。在海、淡水网箱养殖过程中,养殖业者非常关心的是养殖对象的生长情况(如饵料的摄食、死亡等)和环境变化状况(如箱体、网具是否完好,箱内水质等)。对     

自减流低形变网箱减流效果

本文通过在东海水产研究所，主尺度为90m×6in×3In的试验水池内进行模型试验，试验网箱是以圆柱形网箱为基础，在网箱箱体深度的1／2处设置了一个中环，将原来的圆形重力式网箱改造成新型自减流低形变网箱，网箱周长为50m、中环周长75m、深8m，研究其箱体内流速的变化。试验结果表明新型网箱的减流效果比原网箱提高5．8％一13．9％，自减流低形变离岸深水网箱的箱体内部流速比箱体外界流速平均减小25．3％，可有效降低箱体内的海水流速，减小养殖鱼类在网箱内长时间顶流游泳的强度，为养殖鱼类提供良好的生存、生长环境。     

影响网箱养殖的因素及应对措施

一、影响因素1.水质变化影响网箱养殖中,影响水体水质的因素主要是未食的饵料、养殖对象的排泄物以及化学药品等。未食的饵料散落在水体中,增加了营养盐和有机物,造成水体污染,导致养殖对象的排泄物排入水体,造成网箱内氮、磷含量增加,尤其是氨     

史氏鲟网箱养殖技术

近年来,全国各地均开展了鲟鱼人工养殖,但由于养殖鲟鱼的时间短,在养殖技术及疾病防治方面技术不甚完善,笔者就这几年史氏鲟网箱养殖的经验作一总结。一、网箱设置地点网箱设置在水面开阔、水质清新、无污染的地方,一般要求水深4m以上,水深最好在6m~8m,如果水位过浅则不利于网箱内外的水体交换,使水质恶化而影响鱼体生长,甚至造成缺氧死鱼。网箱一般设置在流速0.2m/s～0.3m/s的水域。网箱在鱼种放养前宜提早入水设置,待网片着生藻类等附着物后再放养鱼种,以免擦伤鱼体。二、网箱结构和安装网箱规格不易过大,一般为3m×3m×3m、4m×4m×3m或5…     

建鲤繁殖养殖技术操作要点(4)

四、网箱养殖(一)网箱放置场地的选择放置网箱的水域,应选择在水质肥沃、无污染、水温适宜、向阳避风、底部平坦、深度适中(常年保持4～7米)、不受洪水影响的库湾水域为好。(二)网箱结构和安置1、网箱结构:网箱通常用6片网片加工缝制而成的封闭或敞口式箱体。呈正方形或长方形,四周固定在用楠木或方形木条绑扎成的框架上。养鱼种的网     

网箱养殖对水质的影响

网箱养殖随着规模和养殖强度的扩大，许多水体局部或全部水质恶化，就其网箱养鱼对水质的影响研究进展作此综述。     

水库网箱养殖史氏鲟技术总结

小浪底水库自蓄水以来,养殖品种单一,而其渔业资源丰富,水质条件较好,很适合鲟鱼的养殖。为此,我们于2002年在小浪底水库进行网箱养殖史氏鲟商品鱼的试验。本文就网箱养殖试验中不同的放养密度对单位生产量和个体规格的影响做一总结。1水库条件小浪底水库位于河南、山西两省八市(县)境内,水库蓄水达到兴利库容后,我省境内的可养鱼水面约40多万亩,水库水质较好,溶氧充沛,无毒无污染,较多长而宽阔的库湾,适合网箱养殖。2网箱制作及设置养殖试验在小浪底水库济源境内的王拐湾进行。网箱由市售聚乙烯网衣缝制,规格为5米×5米×3米,分内外两层网…     

水库网箱养殖光倒刺鲃试验

2005年,我们承担了阳朔县科技局下达的《水库网箱养殖光倒刺鲃试验》项目。从2004年8月开始,我们在阳朔县白沙水库设置网箱养殖光倒刺鲃,现将试验情况总结如下:一、基本情况1.水域环境条件白沙水库总面积30公顷,库容362万米3,水库正常水位面积21公顷,库容230万米3。水库底部平坦,平均水深约7米。水库水质经广西渔业环境监测中心采样检测,符合养殖业无公害农产品养殖生产用水标准。2.网箱设置网箱箱架采用角钢焊接,油桶作为浮子;箱体采用聚氯乙烯网片缝合而成;箱体为双层网片,网目规格为2a=3.5厘米,箱体规格5米×5米×2.5米、4米×4.5米×2.5…     

象山港三种不同养殖方式对浮游动物群落的影响

为探究不同营养类型养殖方式对半封闭海湾浮游生态系统的影响,于2015年在象山港的鱼类网箱养殖、牡蛎筏式养殖和海带筏式养殖3种养殖区内外分别进行大、中型和中、小型浮游动物群落及相关环境因子的四季研究。结果显示,牡蛎养殖区内大、中型浮游动物群落结构变化明显,夏、秋季优势种太平洋纺锤水蚤的优势度下降,冬季优势种腹针胸刺水蚤的优势度上升;网箱养殖区内浮游动物群落变化不明显,变化主要为大、中型浮游动物优势种,春、冬季腹针胸刺水蚤的优势度下降,秋季优势种种类组成变化明显;海带养殖区内浮游动物群落和优势种变化均不明显。此外,3种养殖方式对浮游动物的生物量、丰度和α多样性均未产生明显影响。结合象山港的水文特征和养殖区内外的环境因子,研究表明,牡蛎养殖区浮游动物群落变化是牡蛎滤食行为和铁港水交换能力差的综合结果,而浮游动物优势种变化可能与水体总磷含量较高有关;因目前网箱养殖规模小且西沪港水动力条件较好,网箱区内局部环境和浮游动物的变化较小;海带养殖因面积小且仅春、冬季养殖,不足以对水质和浮游动物产生影响。此外,本研究显示不同环境中,大、中型浮游动物群落结构的变异较中、小型浮游动物明显,这可能与中、小型浮游动物群落的稳定性较高有关。     

海水网箱网衣防污技术的研究进展

海水网箱养殖中,网衣污损附着物会影响网箱设施安全及其养殖鱼类的健康生长,因此,网衣防污是网箱养殖业备受关注的问题。本文在简述海水网箱网衣分类与特点的基础上,重点介绍了人工清除法、防污涂料法、机械清除法、金属合金网衣防污法、箱体转动防污法、生物防污法、网衣本征防污法等网衣防污技术最新研究进展;结合本课题组在网衣防污方面的研究成果,分析上述防污技术的特点,为网衣防污技术的深入研究以及水产养殖业的绿色发展提供参考。我国海水网箱养殖业大有可为,但网衣防污工作仍任重道远。     

海水循环养殖系统冬季运行水温和水质控制

为探讨江苏沿海地区海水鱼类养殖过程中的越冬问题,构建了基于温室保温与微藻净水的封闭式循环水养殖系统,用于开展黑鲷越冬试验。通过在线监测系统记录冬季运行期间系统内外水温与气温,研究太阳能温室的保温性能;通过定期采样检测养殖系统水质,比较投加微藻前后养殖池水质的差异,研究微藻净水的可行性。结果显示:冬季温室内海水循环养殖系统的平均水温显著高于温室外水温,有利于黑鲷顺利越冬并延长生长期;在养殖系统内接种微藻可有效降低水体氨氮(NH+4-N)浓度,并将亚硝酸盐氮(NH-2-N)浓度维持在较低水平,有利于维护养殖系统水质稳定。研究表明:集成温室保温与微藻净水的海水循环养殖系统可实现黑鲷越冬养殖。本研究可为存在积温不足和越冬问题的区域发展海水鱼类养殖提供参考。     

Field measurements of cage deformation using acoustic sensors

As aquaculture continues to supply an increasing share of the worldwide seafood demand, it will become critical for farmers to maximize their efficiency. Presently, the majority of marine finfish are produced in gravity type net pens which can deform when they are subjected to currents. The water velocity loading affects the overall net shape which results in net cage volume loss and consequently, increases fish stress and decreases growth rates.In this study, an acoustic method is utilized to monitor the deformation of a small-scale fish cage deployed in currents. Twelve acoustic sources and four hydrophones were deployed on and around a small scale net pen for 60 days to monitor the net cage movement and volume. Local current velocities were recorded using two current meters, one inside and one outside the net pen. Three volume approximation techniques were examined, using the positions of the acoustic sources to predict net chamber volume as it responded to the currents. A numerical model of the system was then configured, set with loads under similar water velocities and results between field measurements and the model were compared.The use of acoustic sources and hydrophones to monitor cage deformation was shown to accurately monitor net deformation. Field measurements compared well to numerical model predictions, with errors ranging from −3.8% to 32%, depending upon the number of acoustic sources employed in the volume calculations. At low water velocities, six acoustic sources were found to accurate predict the net pen volume. In higher currents, a minimum of nine acoustic sources was recommended.     

Effects of water flow velocity and fish culture on net biofouling in fish cages

The effects of water flow, fish feed and cage position on net biofouling was examined in a floating cage fish farm. Fouling of 16 mm mesh net panels suspended inside and outside net cages and exposed to different treatments were monitored weekly until net apertures were completely occluded by the fouling organisms (8 weeks). Results indicate a dramatic reduction in water flow velocity throughout the fish farm due to the cage units themselves and net biofouling. The reduced water flow (<10 cm s^?1) inside net cages promoted rapid net biofouling, while rapid water flow outside the net cages (>25 cm s^?1) kept the net fouling organisms at bay. Although fish rearing in net cages with inputs of commercial pellet feed increased sessile biofouling (222% higher than outside the net cages) and non‐sessile biofouling (570% higher), the type of fish feed used did not significantly affect biofouling development. The study recommends that the geometry of serially arranged net cages, as commonly deployed in tropical tidal estuaries, be reconfigured to improve flow through in order to minimize the impact of fouling.     

奥尼罗非鱼水库网箱养殖技术

2008年4月～10月，在福建尤溪水东水库开展奥尼罗非鱼水库网箱集约化养殖试验，结果表明：投放平均体重为27g的奥尼雄性罗非鱼，经过190d的饲养，鱼体平均体重1062g，产品符合水产品质量安全要求，平均成活率达98．0％，饲料系数为1．7，平均盈利244元／m^2，创造了良好的经济效益。本文从水源条件、养殖设施、养殖密度、饲料和饲养管理等方面，总结了福建尤溪水东水库罗非鱼网箱健康养殖的技术要点，为福建溪流型水库开展罗非鱼网箱健康养殖提供参考。     

网箱养殖对白洋淀草型湖泊水质的影响

为研究白洋淀网箱养鱼对北方浅水草型湖泊水质的影响,选取不同养殖年限下的网箱进行采样监测,分析白洋淀有关环境因子与养殖时间的相关性,并建立相应的回归方程。结果表明：白洋淀网箱养鱼的养殖时间与湖泊水体的环境因子DO、Chl.a显著负相关,与COD显著正相关;养殖时间与NH4＋-N、NO3-N和TN显著正相关,与NO2-N无...     

网箱鲤鱼单极虫防治技术的研究

近年来我省网箱鲤鱼单极虫病比较严重,影响水库网箱养殖业的发展,因此及时提出防治措施是当务之急。防治措施一是把住放养关,严禁病鱼入箱;二是采用各种药物内服、外用进行治疗。经查明,黄壁庄水库网箱鲤鱼单极虫流行病与水库水温有密切关系,与水库水质无关。     

Aquacultureagriculture systems integration: an Australian prospective

The concept of integrating aquaculture with irrigated farming systems was evaluated in three projects in the GoulburnMurray Irrigation District (GMID) in south-eastern Australia. (1) Semi-intensive cage culture trials using silver perch, Bidyanus bidyanus (Mitchell), were undertaken in a range of irrigated farming systems: irrigation supply channels; groundwater supplies; and on-farm storage dams. Survival and growth of fish under these conditions were comparable to fish reared in conventional aquaculture ponds. However, poor water quality at some sites reduced survival and growth. (2) A study was undertaken to assess the feasibility of the cage culture of silver perch and rainbow trout, Oncorhynchus mykiss (Walbaum), in three irrigation water storage reservoirs. Conditions within each reservoir, particularly water quality, wind and wave action, and cage fouling, varied considerably, and influenced fish growth and survival. (3) Mariculture trials were undertaken in two saline groundwater evaporation basins, which were part of an integrated agriforestry and salt reclamation system. The species tested included two oyster, two prawn and nine fish species. Some species exhibited exceptional survival and growth rates under trial conditions. These projects indicate that the concept of integrating aquaculture with existing irrigated farming systems has the potential to enhance productivity, water use efficiency and overall environmental sustainability in the GMID.     

我国深远海网箱养殖工程与装备技术研究综述

在远离大陆的深远海水域发展大型网箱养殖,已成为缓解近海养殖环境压力、突破资源受限和空间制约问题的重要举措。深远海网箱养殖产业的蓬勃发展,加速促进了养殖方式转型升级和海洋养殖空间大幅拓展,形成了海洋设施养殖新发展格局。本文立足我国网箱养殖产业发展现状,分析深远海网箱养殖产业发展需求、发展前景以及设施装备科技需求,详细介绍国内外深远海网箱养殖工程与有关装备技术的研究应用情况,分析我国深远海网箱养殖工程与装备发展面临的主要问题,并从科学规划、科技引领、规范建设和创新模式等方面,对深远海网箱养殖产业发展提出相关建议。