Multi-residue and multi-class determination of antibiotics in gilthead sea bream (Sparus aurata) by ultra high-performance liquid chromatography-tandem mass spectrometry

This paper describes a method for the determination of 41 antibiotics from seven different classes in gilthead sea bream (Sparus aurata) by ultra-high-performance liquid chromatography with tandem mass spectrometry (UPLC-MS/MS). Sulfonamides, trimethoprim, tetracyclines, macrolides, quinolones, penicillins and chloramphenicol were simultaneously determined. Fourteen procedures for sample treatment were tested and an extraction with acetonitrile and ethylenediaminetetra acetic acid was found to be the best option. The methodology was validated in accordance with Decision 2002/657/EC. Precision in terms of relative standard deviation (RSD) was under 17% for all compounds, and the recoveries ranged from 92% to 111%. CCα and CCβ were determined according to the maximum residue limit or the minimum required performance limit, when necessary. The validation provided evidence that the method was suitable for application in routine analysis for the detection and confirmation of antibiotics in muscle of gilthead sea bream, an important and intensively produced fish in aquaculture.     

环境友好型水产养殖业发展战略

本项研究在总结我国水产养殖业发展主要经验基础上,论述了进一步发展水产养殖业的战略意义。在绿色、低碳和碳汇渔业发展新理念引导下,提出环境友好型水产养殖业发展战略,主要包括:推动水产养殖业现代化发展的"养护、拓展和高技术"三大发展战略;实现水产养殖业"高效、优质、生态、健康、安全"可持续发展的任务目标;近期需着力构建的现代水产养殖业创新发展体系的重点任务等。针对目前产业存在的问题和发展需求,提出重视水产养殖对发展空间的需求、建立养殖水域容纳量评估制度、发展生态系统水平的新型养殖生产模式、实施养殖装备提升工程、加强水产养殖管理与执法能力建设等对策建议。     

海洋渔业碳汇及其扩增战略

本文介绍了海洋渔业碳汇和碳汇渔业的定义、研究现状、问题及技术需求。与林业碳汇比较结果表明,海洋渔业碳汇不仅有高效的特性,还有扩增的潜质。为此,提出海洋渔业碳汇扩增对策建议,主要包括:查明我国海洋渔业碳汇潜力及动态机制;大力发展以海水养殖为主体的碳汇渔业;加强近海自然碳汇及其环境的养护和管理;实施相应的渔业碳汇扩增工程建设,促进环境友好型水产养殖业发展。     

3种微生态制剂对幼刺参养殖水体水质的影响

对3种微生态制剂改善幼刺参养殖水体水质的效果进行了研究。试验设3个处理组,分别在水体中泼洒芽孢杆菌、海洋红酵母和EM菌;另设1个对照组,只投喂基础饵料。试验水体20L,试验期间不换水,每隔2d对pH、化学需氧量、氨氮及亚硝酸盐氮进行检测,氨氮超过0.15mg/L时结束试验。结果表明,在水体中泼洒3种微生态制剂均可改善水质,其中,EM菌和海洋红酵母具有降低化学需氧量的作用,EM菌和芽孢杆菌具有降解氨氮和亚硝酸盐氮的功能,EM菌改善水质的效果最好。     

水产养殖对水环境的影响与污染控制对策

概述了水产养殖的发展现状和在环境、病害、苗种、管理等方面存在的问题，并结合实际提出了控制水产养殖对环境污染的对策。     

海工型渔业养殖网箱技术现状与发展趋势

传统的海水养殖主要以近岸养殖为主,近年来,沿海渔业养殖空间趋于饱和且水质污染愈发严重,海水养殖走向深远海已成必然趋势。本文回顾了国内外养殖网箱技术,从原始的渔排到网箱,再到海工型渔业养殖网箱的发展历程。随后通过对国内外几种典型的海工型深远海养殖网箱技术与装备进行了分析和对比,发现该技术与装备存在养殖水体容量小、用途单一或环境污染问题。养殖网箱未来将向大型化、平台化、智能化、环保化等方向发展,其中采用以波浪能为代表的可再生能源与养殖网箱相结合是今后发展的方向之一。     

The effect of recirculating aquaculture systems on the concentrations of heavy metals in culture water and tissues of Nile tilapia Oreochromis niloticus

To date, farming fish in recirculating aquaculture systems (RAS) is one of the most environmentally friendly ways of producing fish. However, with the trend towards intensification, and consequently decrease in water exchange rates, these systems may accumulate substances, such as heavy metals, in the water and fish. Inductively-coupled plasma-optical emission spectrometry (ICP-OES) and inductively coupled plasma-mass spectroscope (ICP-MS) were used to determine Al, As, Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn, in the water and fish (Nile tilapia Oreochromis niloticus). Three RAS were used, differing in daily water exchange rates (30, 70 and 1500 l/kg feed/d). The concentrations of As, Fe, Mn, Ni and Zn in the water increased with decreasing water exchange rates, suggesting an accumulation of heavy metals as more water was re-used. Such accumulation in the water was, however, not translated into accumulation in the liver and muscle. Accumulation of heavy metals was always higher in the liver than in the muscle; however, As reached 1.61 mg/kg wet weight in the muscle of fish farmed in RAS-70 l/kg feed/d. However, these levels are considerably lower than permissible safety levels for human consumption.     

Water quality and accelerated winter growth of European catfish using an enclosed recirculating system

Aquaculture of the European catfish Silurus glanis is impeded by the slow rate of growth at ambient water temperatures below 10°C, which are encountered during the winter months in many regions of Europe (such as central France). In an effort to increase water temperatures over this period, fish were held in an enclosed housing where the water quality was maintained using a low‐cost treatment plant. For comparison, some fish were held in a separate system that was not enclosed and where water treatment took place in an adjacent earth‐lined pond. Both systems were able to maintain good water quality during the winter months but the recirculating system achieved significantly higher water temperatures and rates of fish growth.     

Investigation of aquaculture dynamics at a Ramsar site,using earth observation systems in conjunction with a socio‐economic assessment

This study presents a comprehensive site‐scale analysis conducted within the global wetland inventory and mapping (GWIM) project. GWIM was developed and promoted by the International Water Management Institute (IWMI) through global partnerships to investigate wetland analyses at multiple scales. The present study investigates the complexity of an inland freshwater wetland system, presenting a conceptual framework for mapping and monitoring the dynamics of Lake Kolleru (a wetland of international importance, as defined by the Ramsar Convention), utilizing a geospatial platform. Illustrating the pace of land use changes leading to the progressive elimination of the wetland ecosystem of freshwater Lake Kolleru, this study also highlights the impacts of such changes on the socio‐economic system. A comprehensive temporal analysis (1977–2007) provided a structural base to schematically analyse the dynamics of biophysical and ecological changes to the wetland by effectively using a spectrum of remote sensing data. The present status and changing trends in ecological dimensions of Lake Kolleru were illustrated, utilizing information from spatial analyses, complimented with socio‐economic assessment. Attention is drawn to the potential of utilizing earth resources systems in exploring space–time interactions in freshwater ecosystems heavily modified through aquaculture interventions. Further, the spatial derivatives are meant as reference material for local authorities and decision‐makers to rehabilitate the economic livelihood activities to the social community dependent on the lake ecosystem. The disseminated message emphasizes the applicability of geospatial tools to enhance the efficacy of the decision‐making process by facilitating regular monitoring of ecosystem dynamics and providing updated information on wetland patterns and uses.     

The Effect of Ozonation on Particle Size Distribution for Recirculating Aquacultural Seawater: Analysis of Particle Flocculation and Breakup

ABSTRACT

Solids removal is very important for water quality maintenance in recirculating aquaculture systems (RAS). Ozonation is a practical water treatment which can promote the solids removal. However, the characteristics of ozonation effects on particles are still unclear. In this study, the effect of ozonation on particle size distribution (PSD) was investigated for seawater from a RAS of Pacific white shrimp (Litopenaeus Vannamei). Both flocculation and breakup of particles were demonstrated during ozonation treatment, which resulted in changes of PSD. By using a fractal characteristic value (D_f), the flocculation process could be divided into three stages of preparation, growth and steady. Besides, the flocculation efficiency varied parabolically with contact time. A higher ozone dosage resulted in a shorter preparation stage, along with a longer growth stage (namely lasting a longer flocculation effect) and thus a relatively higher limit of parabolic flocculation efficiency. However, the limit would reach a peak and probably be accompanied with a more breakup of particles. The best flocculation efficiency was 43% at ozone dosage of 3.5 mg/L with 5 min contact time. Furthermore, a higher ozone dosage could produce more ammonia.