轮虫培育池生态系统浮游细菌的生物量及其动态

研究了半循环流水轮虫培育池(1#)、静水轮虫培育池(2#)和半循环流水轮虫饵料培养池(3#)中浮游细菌的生物量及其动态。结果表明,1#、3#和2#池中浮游细菌的密度依次为(14 55±5 67)×108个/L、(8 44±2 75)×108个/L和(24 52±8 71)×108个/L,而浮游细菌的生物量依次为(6 75±2 63)、(4 39±1 01)和(11 38±4 52)mg/L。在土池轮虫培育中微藻类是主要生产者,浮游植物尤其是微型藻类的数量决定了浮游细菌是否成为轮虫饵料的主要供应者。浮游细菌的数量变化和COD的变化一致。     

主要淡水水产品在养殖模式转换过程中营养品质的形成机制研究进展

随着生活水平的提高人们越来越重视膳食品质,鲈鱼、乌鳢、鳜鱼等几种肉食性鱼类因其较高的营养价值而备受关注。目前,这几种经济鱼类正处在从传统池塘养殖向池塘工程化养殖和从饲喂冰鲜饵料向投喂人工配合饲料养殖模式转变的过程中。本文通过已有研究总结了这几种主要淡水水产品的养殖现状及具体评价营养价值的指标,并对其养殖模式转换过程中的营养价值可能出现的变化进行了综述。讨论总结后发现,投喂人工配合饲料养殖的鲈鱼、鳜鱼等经济鱼类营养价值特别是蛋白质品质低于投喂冰鲜饵料的。而池塘循环水养殖这种新型的养殖模式对这几种肉食性鱼类营养价值的影响尚不明确。但从目前已有研究来看,池塘循环水养殖能够有效改善水质,并在一定程度上限制了有害物质积累。所以这种新型养殖模式对这几种经济鱼类食用品质有积极的影响。本文通过对主要淡水水产品在养殖模式转换过程中营养价值形成机制进行综述,为推行绿色健康可持续的新型养殖模式提供了理论依据。     

全程投喂配合饲料条件下池养中华绒螯蟹的生长性能及其性腺发育

于2012年5月至2013年11月,对池养中华绒螯蟹(Eriocheir sinensis)全程投喂配合饲料,观测扣蟹和成蟹阶段的生长规律、成活率、早熟率、性腺发育速度、产量、规格分布和饲料系数等。结果表明:(1)扣蟹阶段雌雄生长差异不显著(P0.05),增重率(WG)和特定增长率(SGR)为先上升后下降,整个扣蟹培育阶段的平均SGR为1.9%/d左右;平均成活率和早熟率分别为10.0%和4.9%,雌体的早熟率显著高于雄体(P0.05);一龄早熟蟹和正常扣蟹的平均体重分别为19.8 g和7.5 g左右,一龄早熟蟹和正常扣蟹的平均产量分别为229 kg/hm~2和2433 kg/hm~2;扣蟹培育阶段饲料投喂主要发生在7—10月,占全部饲料用量的80%以上,饲料投喂量与扣蟹体重及池塘水温具有一定的关系,扣蟹阶段饲料系数(FCR)为2.15。(2)成蟹养殖过程中,自6月份起雄体体重大于雌体,整个养殖阶段雄体的SGR显著高于雌体(P0.05);雌雄成蟹最终平均体重分别为126.1 g和181.1 g,雌、雄及总体成活率分别为61.30%、53.47%和58.4%,产量分别为412.20 kg/hm~2、536.10 kg/hm~2和950 kg/hm~2;成蟹养殖的饲料消耗主要发生在7—10月,其中育肥前期(9—11月)的饲料用量占50%左右,整个成蟹养殖阶段的FCR为2.63。(3)池养成蟹的生殖蜕壳主要发生在8—9月,雌体比雄体早20 d左右;雌体的性腺发育主要发生在生殖蜕壳后的9—10月,雄体的性腺发育时间跨度较长,生殖蜕壳前性腺指数已达0.8%左右;雌雄成蟹性腺发育期间肝胰腺指数均呈下降趋势。综上,全程投喂配合饲料能保证池养中华绒螯蟹的正常生长发育,可大规模推广应用于中华绒螯蟹养殖产业。     

斑点叉尾鮰养殖池塘底泥微生物群落结构特征及其影响因素

微生物群落在水产养殖环境中起着重要作用,深入了解微生物群落组成及其构建机制对了解池塘生态功能具有重要意义。本研究通过高通量测序技术研究斑点叉尾鮰（）养殖池塘底泥中细菌群落机构特征,并分析了细菌群落的主要影响因素。结果显示,斑点叉尾鮰养殖池塘底泥细菌群落结构呈现出季节性变化,冬春季样品相似性较高。斑点叉尾鮰养殖池塘底泥优势菌群主要为变形菌门（Proteobacteria）、绿弯菌门（Chloroflexi）、拟杆菌门（Bacteroidetes）、厚壁菌门（Firmicutes）和酸杆菌门（Acidobacteria）,与池塘水体细菌群落间有明显的差别。线性判别分析显示,冬、春和秋季的特异性优势菌群较为丰富,冬季和春季分布较为集中,分别集中于浮霉菌、拟杆菌门、绿弯菌门和厚壁菌门、拟杆菌门,秋季特异性优势菌群分布特别分散,而夏季优势细菌类群最少,只有绿弯菌门厌氧绳菌属1个属具有显著优势。环境因子中,透明度和总溶解性悬浮物与斑点叉尾鮰养殖池塘底泥细菌群落结构有显著相关（<0.05）,对细菌群落结构的影响也最大。本研究旨为斑点叉尾鮰池塘微生物群落的变化和调控提供借鉴。     

中国对虾养成期间虾池水体和底质中细菌含量的变化

中国对虾养成期间虾池水体和底质中细菌含量的变化高尚德，陈旭仁，吴以平（青岛海洋大学，２６６００３）（青岛教育学院，２６６００１）关键词养虾池，细菌数量，变化ＶＡＲＩＡＴＩＯＮＯＦＴＯＴＡＬＢＡＣＴＥＲＩＡＮＵＭＢＥＲＩＮＳＨＲＩＭＰＰＯＮＤＷＡＴＥＲ...     

池养脊尾白虾的繁殖、生长及其最大持续轮捕量的初步探讨

池养脊尾白虾经过３个月生长可达性成熟，抱卵亲虾占总虾数比例为３．８４％－１６．７１％，相对抱卵量平均值为５１２．７２粒／克体重。本试验中池养脊尾白虾的体长、体重与月龄关系可用ｖｏｎ Ｂｅｒｔａｌａｎｆｆｙ生长方程描述。在目前的轮捕条件下，３月龄的个体可供渔具选择，年总死亡率φ＝０．６２７０，轮捕死亡率Ｅ＝０．２７４４，自然死亡率Ｄ＝０．３５２６。若把首次轮捕月龄从３月龄提高到４月龄，轮捕强度控制在     

淡水养殖环境中氨氧化微生物的研究进展

随着水产养殖业的快速发展,养殖水体氮素污染日益突出,硝化微生物在水产养殖环境氮循环中具有重要作用。本文主要综述我国淡水养殖环境中硝化微生物的多样性、作用机理、厌氧氨氧化过程和机理等研究进展,并展望今后的研究工作:(1)淡水养殖水域硝化作用和氨氧化微生物的时空分布特征及影响因子;(2)淡水养殖环境氨氧化微生物及其他氮素转化关键微生物的过程与机理;(3)深入研究特定生态系统中如池塘生态系统、氮循环的各个过程,构建相关氮素转化和氮素平衡模型,为完善淡水池塘生态系统氮循环理论、水产养殖环境的氮素污染治理和生态修复提供参考。     

Comparison of food selection and growth performance of koi carp, Cyprinus carpio L., and goldfish, Carassius auratus (L.) in mono- and polyculture rearing in tropical ponds

To compare the effect of polyculture against conventional monoculture on ornamental carp production, investigations on food selection and growth performance of koi carp (K), Cyprinus carpio L. and goldfish (G), Carassius auratus (L.) were conducted in a 11‐week rearing experiment in two monoculture (100% K and 100% G) and five polyculture (90% K–10% G, 70% K–30% G, 50% K–50% G, 30% K–70% G and 10% K–90% G) conditions in tropical ponds. There were three replicates for each treatment. Environmental conditions and food availability were similar in all the treatments. Ivlev's electivity index showed that both fish species avoided phytoplankton and preferred cladocerans to other zooplankton groups (copepods and rotifers) in monotypic conditions. However, in the polyculture treatments, the positive electivity of goldfish towards cladocerans reduced significantly (P<0.05), while the percentage of copepods, rotifers and phytoplankton in the gut content increased. No significant differences in weight gain, specific growth rate and deformities were recorded at harvest for koi carp between the different treatments (P>0.05). Even the survival rate of koi carp recorded above 90% in all the treatments. However, the goldfish recorded significantly better weight gain, specific growth rate and survival in monoculture (100% G), compared with the polyculture treatments (P<0.05). Goldfish deformities were lowest (P<0.05) in the monoculture treatment (2.42%). The number of marketable fish above a set size limit of 4 g total weight was significantly higher in the two monoculture treatments, compared with the five polyculture treatments (P<0.05). Keeping in view of the dietary similarities of koi carp and goldfish, and the aggressive nature of koi carp in polyculture, it is suggested to refrain from polyculture of goldfish and koi carp until further documentations relating to optimum stocking density and management of polyculture of ornamental carps are available.     

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.     

凡纳滨对虾不同养殖密度高位池水体细菌群落动态

通过对养殖水体环境基因组DNA中细菌16S rRNA基因V4–V5区的高通量测序和生物信息学分析,研究了两种养殖密度的凡纳滨对虾(Litopenaeus vannamei)高位池水体中细菌群落在养殖过程中的动态。结果显示,养殖过程中各菌群相对丰度变化明显,细菌多样性随时间逐渐提高,优势菌群为变形菌门(Proteobacteria)、蓝藻门(Cyanobacteria)、拟杆菌门(Bacteroidetes)、放线菌门(Actinobacteria)和浮霉菌门(Planctomycetes)。随着养殖时间增长,蓝藻丰度所占比例逐渐减少,而变形菌、拟杆菌和浮霉菌丰度逐渐增大,同时养殖前期高密度池浮霉菌丰度显著高于低密度池(P0.01),而其他菌群无显著差异。结果表明,养殖期前50 d不同养殖密度水体细菌群落差异较大,而后30 d内细菌群落的时间异质性大于空间异质性,这意味着高位池水体菌相被划分为两类,到养殖后期菌相快速转变,养殖密度所带来的影响被减弱。