《水产养殖概论》课程建设的探索与实践

按照精品课程建设的内容和要求，以培养高素质人才为目标，对《水产养殖概论》课程在教学内容、教学方法与手段、实验教学、课程考核等4个方面进行了探索与实践，并取得了较好的教学效果。     

Settling velocity characterization of aquacultural solids

A top-loading settling column is described and used to characterize the settling properties of the solids in the discharge water from a commercial rainbow trout production facility. Mass-based and phosphorus-based settling curves are presented. The median settling velocity on a mass-basis for the settleable solids was 1.7 cm s⁻¹. The median settling velocity for the settleable phosphorus was 1.15 cm s⁻¹. Manually stripping fecal material from rainbow trout resulted in settleable solids with a median settling velocity of 0.7 cm s⁻¹. Examination of the settling velocity curves show that halving the overflow rate (OFR) from 2 to 1 cm s⁻¹ changes the removal efficiency from 0.61 to 0.73, an increase of about 20%. Halving the OFR again to 0.5 cm s⁻¹ increases the removal efficiency to 0.81, an improvement of about 11%. Settling characteristics of aquacultural solids will vary from facility to facility. The methods described in this paper can be used to perform a similar type of analysis at other aquacultural sites, which may be growing other species under different management regimes.     

Sustainable Aquaculture Products: Implications of Consumer Awareness and of Consumer Preferences for Promising Market Communication in Germany

Sustainability issues are becoming increasingly important in Western food consumption. This research aims at identifying ways to increase the market share of sustainable fish from aquaculture by analyzing consumer awareness and preferences for sustainable aquaculture products and by drawing conclusions on improving communication in the German market. An integrative research approach was used: it began with an inventory of sustainable seafood products on the German market, followed by qualitative and quantitative consumer research, and ending with a stakeholder workshop, which reflected on the research outcome with practitioners. Sustainability and country of origin proved to be of minor relevance to the vast majority of the consumers interviewed. Indeed, attributes such as freshness, taste, and price frequently ranked higher. Like most of the other consumers, the small consumer segment that is generally interested in sustainability issues of food also often lacks knowledge of fish farming and its products. Consequently, communication of sustainability in aquaculture is challenging, and the development of this market requires concerted actions along the whole value chain, with the retail sector as the main actor.     

流沙湾浮游植物群落特征季节变化及其与养殖活动的关系

流沙湾是中国海水珍珠“南珠”的主产区和广东省重要的贝类养殖区。为评估湾内养殖活动的环境效应,于2015~2016年对流沙湾海区进行了夏(8月)、秋(11月)、冬(2月)、春(5月) 4个季节的浮游植物和海水理化因子调查。共检出浮游植物171种,包括硅藻门43属122种、甲藻门 10属44种、蓝藻门2属2种、金藻门2属2种和裸藻门1属1种。流沙湾内湾浮游植物细胞丰度为(0.05~79.04)×104个/L,夏季>春季>秋季>冬季,且夏季丰度远大于其他三季,内湾和外湾差异不显著。春季须状角毛藻(Chaetoceros crinitus)、红海束毛藻(Trichodesmium erythraeum)和明壁圆筛藻(Coscinodiscus debilis)为主要优势种,夏季优势种主要为中肋骨条藻(Skeletonema costatum),秋季优势种主要为拟弯角毛藻(Chaetoceros pseudocurvisetus)、奇异棍形藻(Bacillaria paradoxa)、洛氏角毛藻(Chaetoceros lorenzianus),冬季主要优势种为威氏圆筛藻(Coscinodisus wailesii)、柔弱根管藻(Rhizosolenia delicatula)、岛脆杆藻(Fragilaria islandica)。其中,奇异棍形藻为春、秋、冬季的优势种,红海束毛藻为春、夏、秋季的优势种。冗余分析表明,流沙湾浮游植物优势种在春季与水温和氨氮密切相关,夏季受透明度显著影响,而在秋、冬季受亚硝酸氮含量影响显著。流沙湾不同养殖区的浮游植物多态性和丰度有明显季节差异。与2012年相比,流沙湾外湾的养殖覆盖率提高了近50%,内湾的珍珠贝养殖减少了近90%,养殖品种、规模和分布格局都发生了明显变化,目前流沙湾的浮游植物群落特征正是对其变化的一种响应。夏季鱼类网箱养殖提高了水域营养盐水平并降低了浮游植物多样性。大规模的扇贝养殖则导致了扇贝养殖区浮游植物丰度的降低。     

Infrared reflection system for indoor 3D tracking of fish

Many fish rearing infrastructures are already equipped with human-operated camera systems for fish behavior monitoring, e.g. for stopping the feeding system when the fish is satiated or for monitoring of fish behavior abnormalities caused by poor water quality or diseases. The novel infrared reflection (IREF) system for indoor 3D tracking of fish demonstrated in the current study allows for automation of fish behavior monitoring, reducing the system running costs by eliminating the need for continuous human monitoring and increasing the behavioral analysis accuracy by excluding the human subjectivity factor.The operating principle of this system is based on the effect of strong absorption of near infrared (NIR) range light by water, thus allowing estimation of fish distance based on the corresponding fish object brightness on the camera image. The use of NIR illuminator as a part of the IREF system allows fish behavior monitoring in the dark so as not to affect fish circadian rhythm. A system evaluation under aquaculture facility conditions with Atlantic salmon (Salmo salar) using flow-through water in tanks, showed the mean depth estimation error was equal to 5.3 ± 4.0 (SD) cm. The physiological variations among conspecific individual fish introduced the mean depth estimation error of 1.6 ± 1.3 (SD) cm. The advantages of the IREF system over well-known stereo vision systems are lower hardware cost and less computationally intensive 3D coordinates estimation algorithm, while the disadvantage is lower accuracy that is nevertheless acceptable for most applications of aquaculture fish monitoring.     

农村固体废物回收和循环利用现状及对策

随着农业产业化发展、农村生活水平的提高和人口的迅速增长,农村固体废物种类增多,产生量大幅度增加,而且农村固体废物是重要的环境污染源和疾病传播源。因此解决农村固体废物的处理处置与资源化是农村进一步发展的迫切需要。文章针对农村固体废物污染的现状,从固体废物的组成危害以及现阶段循环利用出现的问题出发,提出了农村固体废物循环利用的相关措施及对策,对促进农村经济发展、改善农村生态环境和农民身心健康具有重要的现实意义。     

微生物固化载体的选择及对养殖水体的作用效果分析

[目的]寻找适合在海水养殖中使用的高效、廉价、易得的微生物固化载体。[方法]通过4种载体对光合细菌吸附效果的比较,选择合适的固化载体和固化时间,通过测定固化微生物对养殖水体COD、NH3-N、底质中有机质和硫化物的去除率,分析其对养殖水体的作用效果和固液比的影响。[结果]炉渣对光合细菌的吸附能力最强,合适的固化时间是8～10 h,其对养殖水体中COD、NH3-N和底质中有机质和硫化物在20 d内的去除率可达66%、52%、57%、82%。[结论]火电厂的炉渣是一种非常适合在海水养殖中使用的固化载体。使用时要注意选择合适的固液比,避免微生物残留培养基对水体负荷的冲击。     

Environmental improvement of seafood through certification and ecolabelling: theory and analysis

The study of environmental impacts of seafood production as a result of ecolabelling and certification is a young yet rapidly growing discipline that lacks theoretical models. Pieces of the model have been suggested in the literature, and these pieces are formalized here realizing the current operating parameters of the global seafood industry. The derived pull‐threshold model assumes that if producers exceed the threshold, there is no incentive to improve while if too far below, improvement is most likely beyond technical or financial means. Thus, a single certification is only a marginal solution to the larger picture. Those producers immediately below the certification threshold are within range or ‘pull’ of the threshold to improve as a result of certification. Results from a single threshold model applied to compliance data indicated that a maximum improvement of 12.5%, achieved when the pull was the greatest and the threshold was at the lower end of the impact distribution. When impacts were continuous (e.g. escapes in aquaculture), greater improvement was observed with thresholds targeting the producers at the higher end of the impact distribution. In all cases, improvement was maximized with a triple threshold model, indicating that single threshold scenario will not drive the greatest movement towards environmental improvement throughout the industry. Innovation is potentially more important in reducing environmental impacts of seafood production and needs to be accounted for as the seafood certification or ecolabelling continues to mature.     

中草药及其配伍对嗜水气单胞菌的抑菌作用

采用二倍稀释法测定了86种中草药对嗜水气单胞菌Aeromonas hydrophila的最小抑菌浓度(MIC)和最小杀菌浓度(MBC),并采用正交试验法研究了对嗜水气单胞菌具有较强抑制作用的中草药配伍。结果表明,五倍子、五味子和乌梅对嗜水气单胞菌的抑制作用最强,最小抑菌浓度和最小杀菌浓度均为12.5mg/ml,可作为防治水产养殖动物嗜水气单胞菌病害的首选中草药。正交试验结果表明,儿茶、五倍子、五味子和乌梅4种药分别以4∶2∶4∶1和1∶2∶2∶4的比例配伍时对嗜水气单胞菌具有最佳抑菌和杀菌作用。     

移动床生物膜变形工艺原位处理水产养殖废水的研究

通过改造的移动床生物膜工艺（MBBR）,结合微孔增氧技术,对某鱼塘废水进行了原位净化处理研究。采用这种组合工艺净化此类废水,COD、NH3-N浓度可以分别降到20.0、0.6 mg/L左右;溶解氧浓度可以达到6.1 mg/L左右。试验证明,该原位处理装置处理此类废水是高效且经济可行的。