对虾养殖池塘内混养鲻鱼和罗非鱼对水环境及对虾生长的影响

通过比较对虾-鲻鱼(SM)、对虾-罗非鱼(ST)混养池塘内营养盐含量、颗粒物质、浮游生物以及对虾生长性能等指标变化, 研究了鲻鱼(Mugil cephalus)、罗非鱼(Oreochromis niloticus)在对虾养殖池塘内(1000 m2)的生态效益。实验时间为100 d。结果显示, 实验期间SM 和ST 组池塘水体中氨氮(NH4⁺-N)、总氮(TN)、总磷(TP)、活性磷(SRP)、颗粒物质(TPM)等均表现出增加的趋势; 在实验中后期, SM 组池塘水体中的溶解态氮(NH4⁺-N、NO3 ^– -N)低于ST 组, 然而TN 含量却高于ST 组, 且在实验后期表现出显著差异(P<0.05); 同时, SM 组池塘水体中的颗粒物质含量高于ST组, 表明SM 池塘水体中较高的TN 含量是源于悬浮颗粒物质。2 个混养池塘内浮游生物和叶绿素a 含量变化范围分别为5.72-16.83 μg·L–1 和4.35-15.32 μg·L–1, 无显著差异。实验表明, 鲻鱼的扰动可以促进底部有机质向上层水体迁移,有利于降低NH4⁺-N、NO3 ^– -N 等物质的积累和促进养殖系统内物质循环; 对虾存塘率和鱼类取样结果表明, 鲻鱼可以与对虾直接混养, 罗非鱼通过围网隔离养殖可以取得更好的效果。鲻鱼和罗非鱼对养殖系统不同粒径浮游植物的滤食能力需要进一步研究。     

惠东海龟湾水质生态学评价与微生物群落结构特征

惠东港口海龟国家级自然保护区是中国大陆仅存的海龟繁殖栖息地,监测其水体质量及微生物群落对于保护区日常管理和维护区域生态环境具有重要意义。根据地形分布特点,设置14个采样点对该保护区水域水质进行评价,同时采用高通量测序技术对微生物群落组成（细菌、真菌、微型真核生物）进行调查。结果表明：海龟湾水质定性评价为优,营养状态为贫营养。海龟湾海域微生物种类丰富,细菌分布于14门66科96属,变形菌门（Proteobacteria）(82.2%)为优势类群,其次是拟杆菌门（Bacteroidetes）(6.6%);真菌分布于3门16科22属,优势类群为子囊菌门（Ascomycota）(98.5%);微型真核生物群落主要由节肢动物门（Arthropoda）(59.9%)和顶复亚门（Apicomplexa）(16.5%)组成。比较两对微型真核生物引物扩增效果,发现物种组成差异显著,需同时使用才能客观反应海龟湾水域微型真核生物多样性。本研究为保护研究区域海洋生态系统健康提供科学依据。     

基于生态位和水质因子的草鱼两种混养模式的比较

试验通过模拟草鱼2种混养模式("鲮-草模式"为草鱼与鲮混养、"鲫-草模式"为草鱼与鲫鱼混养),引入计算机视觉技术分析了草鱼在2种不同养殖模式下的生态位宽度及生态位重叠,同时测定了水体理化指标及鱼类特定生长率。结果表明:"鲮-草模式"组草鱼的特定生长率为1.524%.d-1,显著高于"鲫-草模式"组草鱼的特定生长率(1.346%.d-1);"鲮-草模式"组水体中的铵态氮、硝酸盐、总氮、总磷、活性磷酸盐浓度高于"鲫-草模式"组,而pH、DO、亚硝酸盐浓度及叶绿素a含量低于"鲫-草模式"组;2混养组中草鱼之间的生态位宽度无明显差异;"鲮-草模式"组草鱼与鲮之间生态位重叠指数为0.5598,"鲫-草模式"组草鱼与鲫鱼之间的生态位重叠指数为0.6478,二模式组比较,差异显著;鲮与草鱼之间的竞争较鲫鱼与草鱼之间的竞争小;试验组中鲮与草鱼混养要优于鲫鱼与草鱼混养。     

光周期对四眼斑水龟繁殖影响

为探讨光周期对四眼斑水龟(Sacalia quadriocellata)繁殖的影响,于2008年10月至2009年9月对其进行光周期实验.将39只成体分成短光照组、长光照组和对照组,每个组别中样本量均为7♀、66.每月用超声波技术对雌性个体进行卵泡数量、大小的检测,并用X光投射法确定硬壳卵数;每半月对雄性进行录像观察.结果表明:三个实验组卵泡数量和卵泡大小表现出明显的周期性,原始卵泡从8月份开始生长发育,卵泡数量在11月份最多,尺寸在12月份也达到最大值;光周期对雌性卵泡数量和卵泡大小的发育有影响,短光照组检测到的总卵泡数高于长光照组和对照组,其中短光照组卵泡数与对照组卵泡数差异显著(P＜0.05),长光照组卵泡尺寸相对于另外2个实验组显著变小(P＜0.01);光周期对雌性产卵数和雄性发情强度无影响(P＞0.05).光周期对四眼斑水龟雌雄个体性腺发育的作用不同,缩短光照对雌性繁殖有促进作用,延长光照对雄性发情强度在特定阶段具有一定促进作用.     

池塘混养模式下生态基对鲤生长及水质的影响

为探索池塘混养模式下生态基对鱼类生长的影响, 在6个土池中进行了一个饲养试验, 将土池分为2组, 一组为不放生态基的对照组, 另一组为放置生态基的生态基组, 每组3个重复。将尾均重为(310±11) g鲤3867尾、尾均重(810±15) g鲢及鳙370尾平均分别分为2组, 平均放养于6个土池中。对池塘鲤每天饲喂颗粒饲料3次, 饲养周期62d。在饲养期内, 每隔10天左右采集水样与底泥样品, 检测其中的浮游生物与微生物群落。在饲养结束后, 将试验鱼捕出并称重, 计算鲤的饲料效率。结果表明, 生态基组鲤鱼的增重率与饲料效率显著高于对照组; 生态基组的鲢、鳙末重显著低于对照组; 生态基组水体透明度与微生物群落多样性显著高于对照组; 生态基组浮游生物浓度低于对照组。结果表明, 在混养模式下土池中生态基的应用有利用促进鲤的生长, 然而池塘生态基的应用对于滤食性鲢、鳙的生长并无促进作用。     

对虾-罗非鱼-缢蛏封闭式综合养殖的水质研究

研究了对虾、罗非鱼和缢蛏封闭式综合养殖的环境状况.结果表明,混养各组环境状况总体要优于单养组.实验期间混养组DO的波动幅度略小于单养组,最低值则高于单养组;各混养组COD值和水层细菌数量相互差异不显著,但各混养组均显著低于单养组(t检验,α<0.05),混养围隔水体有机质含量明显低于单养;混养各围隔组中浮游生物生物量、Chl.a均低于单养组,滤食性动物对浮游生物的压制作用明显.在底泥中,混养组N、P的积累量比单养组低39.76%和51.26%,混养组细菌总数则比单养组低7.63%.本研究表明,封闭式综合养殖可以大大减少注入近海的养殖污水的排放量,从而降低对近海水质的污染.     

人工鱼礁建设对浙江嵊泗海域营养盐与水质的影响

根据2003-2007年对嵊泗人工鱼礁海域11个航次调查所获得的实验数据,运用鱼礁区和对照区相比较的方法,分析了该海域不同季节氮、磷营养盐和水质在投放人工鱼礁后的变化,并对海域水质状况进行评价。结果表明,无机氮大多数处于阈值范围或低于最小阈值,活性磷酸盐含量则严重超标,N/P值范围为0.6280-14.8273,嵊泗海域处于氮限制,溶解氧不成为该海域浮游生物的生长限制因子。投放人工鱼礁后,生态效应不能在短期里得以体现,鱼礁区的水质情况要好于对照区,海域对P的富集强度大于N,人工鱼礁建设对再生生产力影响较大,对新生产力的贡献很小。       

水温变化对绥芬河滩头雅罗鱼产卵的影响

The Dace ( Leucisus brandti Dybowski) was a migration fish in Suifen river. The Dace can spawn at the water temperatures from 7℃ to 25℃. Changing of water temperature is the leading factor cause the spawning population to ovulate. However, high or low current water temperature had no obvious effectuation on ovulating behavior of Dace. The ovulation of the Dace often occurred in the evening or next morning after the water temperature rapidly in creased. The fish spawning often occurred as the water temperature decreased at first, after a period of steady low water temperature, then increased. A massive ovulating action began at the time. If the rising of water temperature happens only after a period of steady level without any decreasing of the water temperature, the change can not stimulate ovulation of the Daces. Usually, every large scale ovulate can sustain for 1 or 2 days. The peak time of ovulation often appears in 48 hours after the water temperature increases. Once the spawning population began to ovulate, their actions will be very intense, so that even catching action of human on them can not prevent the ovulation. The test of artificial induced ovulation showed that only when variation of water temperature were more than 10℃ ( increased degree+decreased degree), the Dace would ovulate. The Dace began to ovulate in 12～36 hours after the water temperature's change. The efficient time was shorter and the ovulation rate was higher the variation of water temperature were greater. At the range from 8℃ to 24℃, as high or low water temperature had no effect on the efficient time stimulating ovulate, the Dace can not ovulate out of the temperature range.     

黄喉水龟繁殖期输卵管组织结构变化的研究

本文研究了黄喉水龟在繁殖期输卵管组织结构变化,得到如下结果：１．黄喉水龟输卵管组织结构由浆膜、肌层、粘膜三层组成。２．将输卵管人为分成上、中、下三段时,上段管壁最薄,中段较厚,下段最厚,肌层发达。３．排卵时,因粘膜上皮纤毛和肌肉收缩活动,将卵向泄殖腔方向推送。４．中段腺体细胞所含分泌颗粒多,表明此段比上段代谢旺盛。     

混养青蛤对南美白对虾池塘氮含量的影响

对虾贝混养池中的氮含量变化规律进行了研究.结果表明,水体内氨氮、亚硝酸盐氮和硝酸盐氮的转化过程影响因素仍以自然因素为主,放养青蛤对其变化规律影响不明显.放养青蛤的池塘水体和底泥总氮含量明显栽低于未放养青蛤的池塘,平均值分别为17.08 mg/l、0.075 mg/g和24.42 mg/1、0.11 mg/g.实验说明混养青蛤可以减少养殖池塘中总氮的含量.     

Changes in the fish community and water quality during seven years of stocking piscivorous fish in a shallow lake

SUMMARY 1. Piscivores (annual stocking of 1000 individuals ha^?1 of 0+ pike and a single stocking of 30 kg ha^?1 of large 20–30 cm perch) were stocked in seven consecutive years in a shallow eutrophic lake in Denmark. The stocking programme aimed at changing food‐web structure by reducing zooplanktivorous and benthivorous fish, with resultant effects on lower trophic levels and ultimately water quality. 2. The fish community and water quality parameters (Secchi depth, concentrations of total phosphorus, chlorophyll a and suspended solids) were monitored between 1996 and 2000 and relationships were evaluated between predatory fish and potential prey and between zooplanktivorous or benthivorous fish and water quality parameters. In addition, potential consumption of piscivorous fishes was calculated. 3. The density of fish feeding on larger zooplankton or benthos (roach >15 cm, crucian carp >15 cm) declined distinctly during the study period. This effect was attributed to predation by large (>50 cm) pike. Based on scale readings, we cautiously suggest that the stocking of 0+ pike boosted the adult pike population to produce an unexpected impact in later years. Conversely, no direct impact of stocked 0+ pike was detected on 0+ roach. 4. A major decline in the recruitment strength of 0+ roach was observed in 2000. A combination of (i) the indirect effect of large pike preying on adult roach, with negative effect on roach reproduction and (ii) the direct predation effect of 0+ pike and/or 1+ and 2+ perch recruited in the lake, provides the most likely explanation of this phenomenon. 5. A marked increase in Secchi depth in 2000 and declining trends in suspended solids, chlorophyll‐a and total phosphorus concentrations were observed. These changes may also be attributable to changes in the fish community, although the relationships were not straightforward. 6. This 7‐year study indicates that piscivorous fish may be a significant structuring force in shallow eutrophic lakes, suggesting that stocking piscivores can increase predation pressure on cyprinids. However, the general lack of impact of 0+ pike points to the need of refining current stocking practices in several countries across Europe.     

海洋鱼产品品质的影响因素及其标准化

影响海洋鱼产品品质的因素有很多,如鱼体含水量、肉质及传统加工过程中一些原料的用量(如糟制过程中食盐、酒糟等的加入量)、贮藏过程中贮藏条件的改变等,加工和贮藏过程中水分活度、色泽、pH、酸价、过氧化物值、硫化巴比妥酸值、挥发性盐基氮、蛋白质水解程度及微生物等一些指标可以反映海洋鱼产品的品质。本文对影响海洋鱼产品品质的因素及上述指标一些常用的检测方法进行阐述,并简要论述国内外海洋鱼产品的标准化,以期对控制海洋鱼产品品质提供借鉴。     

实验用鱼遗传质量控制及标准化

在遗传学及其他生命科学研究领域, 实验用鱼已成为一类应用越来越广的实验动物, 但是尚缺少标准化的质量控制标准和监管。在我国, 实验动物实行严格的许可证制度和质量监督制度。实验用鱼遗传质量控制标准是实验用鱼质量控制的基础。为了规范实验用鱼的遗传质量, 避免实验用鱼种质退化、遗传漂移, 导致实验结果误差, 开展了本标准的研究。依据《实验动物管理条例》, 参考国内外实验用鱼遗传学相关的研究成果, 结合我国实验用鱼生产和使用的实际情况, 在全面收集、分析实验数据和广泛征询专家意见的基础上, 以实验用斑马鱼和剑尾鱼遗传质量控制为规范对象, 研究制定了实验用鱼遗传质量控制标准, 供科研工作者参考、讨论。本标准对实验用斑马鱼和剑尾鱼的遗传分类及命名原则、实验用鱼的繁殖方法、近交系和封闭群的遗传质量监测进行了规范。新标准将为实验用鱼的使用和管理提供理论支撑。     

Long-term changes in crustacean zooplankton and water quality in a shallow, eutrophic Chinese lake densely stocked with fish

From surveys made in 1962–1963, 1973–1974, 1979–1996 at two Stations in Lake Donghu, a shallow eutrophic water body near Wuhan, P. R. China, the authors, derive long-term changes in species composition, standing crop and body-size of planktonic crustaceans. The species number decreased from the 1960s to the 1990s. The cladocerans dropped from 46 (1960s) to 26 (1980s) to 13 (1990s); the copepods decreased from 14 (1960s) to 10 (1980s) to 7 (1990s). From the mid-1980s on, the dominant crustaceans also changed: Daphnia hyalina and D. carinata ssp. were replaced by Moina micrura and Diaphanosoma brachyurum at Stations 1 and 2, respectively; Cyclops vicinus replaced Mesocyclops leuckarti.Densities and biomass of Cladocera decreased markedly after 1987. Annual average densities and biomass of cladocerans were statistically differences between 1962–1986 and 1987–1996 (P > 0.01). Annual average densities of Daphnia (Station 1 + Station 2) were negatively correlated with fish yield .Since the 1980s, annual average body length of Cladocera and Calanoida decreased, while annual average body length of Cyclopoida increased. In the same years, average body length of copepods was lower during May–October than during January–April and November–December.A 12-yr data analysis showed annual average concentration of chlorophyll^-a (Chl^-a) to be negatively correlated with annual average density of Daphnia, whilst lake transparency was positively correlated with annual average densities of Daphnia. The results imply that, since Daphnia feeds efficiently on phytoplankton, it could decrease concentration of Chl^-a, and enhance water transparency.     

Chernobyl-derived radiocaesium in fish as dependent on water quality and lake morphometry

¹³⁷Cs concentrations in perch Perca fluviatilis , pike Esox lucius and roach Rutilus rutilus obtained from lakes of different size and water quality in an area which received about 10–67 kBq m⁻²¹³⁷Cs, were compared with environmental data. Radiocaesium concentrations were highest in pike, and were about two to three times higher in the pike and perch than in the roach. The largest perch had about four times more ¹³⁷Cs than the smallest ones, but the activities in the pike and roach were independent of fish size. All of the water quality parameters examined correlated with ¹³⁷Cs concentrations in the fish, but the concentrations of ¹³⁷Cs in the bottom sediment did not. ^l37Cs fallout and water retention time in lakes showed a positive correlation with fish ¹³⁷Cs, while the size of the catchment area, phosphorus content of the water, water colour, pH and electrical conductivity showed a negative one. Thus there was more ¹³⁷Cs in the fish from the oligotrophic lakes than from the eutrophic ones, from the less humic lakes than from the more humic ones, from the more acid than from the less acid ones and from the lakes containing less potassium than from those containing more potassium. The depth, area and volume of the lake did not affect radiocaesium in the fish. Regression equations are presented for predicting ¹³⁷Cs in fish on the basis of environmental data. Fallout, total phosphorus and pH together had the highest influence in multiple regression models but were less significant in the roach than in the perch and pike.     

Effects of entrapment and cooling water discharge by the Bergum Power Station on 0+ fish in the Bergumermeer

The numbers, distribution and size of 0+ fish in Bergumermeer and in the cooling water system of the Bergum Power Station were registered from 1978 to 1981. An exponentially decreased vulnerability to entrapment by the power station was found with increasing size of fish. Because of the large water intake in relation to the lake volume, entrainment mortality of fish larvae in May and June is large and probably of the same order of magnitude as the natural mortality. In the same period the Bergumermeer can be supplied with large amounts of fish larvae, immigrating passively with the water current. Impingement mortality later on in the season is insignificant compared with natural mortality. The heated effluents from the power station influence the distribution and the size of 0+ fish in the lake. Year-class strength of pikeperch may be improved due to the larger size of 0+ pikeperch. Less water intake as a possibility to minimize entrainment is discussed.     

离岸消浪堰式湖滨带生态修复工程对水质的影响

离岸消浪堰式湖滨生态修复工程系采用离湖岸线一定距离的桩基消浪堰,在湖堤硬质化、湖滨植被带缺失的湖滨带实现控浪促淤,形成半封闭型的人工湖湾以恢复湖滨植被带的工程措施.修复工程形成了堰内挺水植物区、堰内沉水植物区和堰外开阔水体3个生境梯度带.本文以无锡市太湖贡湖湾离岸消浪堰式生态修复工程为研究对象,于2010年6月至2011年5月对工程区3个生境梯度带的水质状况进行了研究.结果表明:消浪堰内亚硝态氮与硝态氮总体上低于堰外,但铵态氮和总氮总体上高于堰外.秋冬季磷素指标堰内浓度低于堰外,但春夏季多高于堰外.堰内水体亚硝态氮和正磷酸盐浓度的变异系数减小,硝态氮、亚硝态氮和正磷酸盐的年最高浓度值低于堰外;但铵态氮和总氮的变异系数增加,且堰内铵态氮、总氮的年最高浓度值高于堰外.修复工程在生长季末期可在一定程度上加剧铵态氮、总氮等水质指标的恶化.     

Use of artificial substrates for standardized sampling of macroinvertebrates in the assessment of water quality by the Belgian Biotic Index

The paper reviews 3 years of experience in Belgium and Portugal with artificial substrates for collecting macroinvertebrates used in water quality assessment by means of the Belgian Biotic Index (B.B.I.).Artificial substrates provide a valid alternative method for sampling the macroinvertebrate fauna and the possibility of standardizing the sampling effort, whereas sampling with a handnet may be more subjective.Research has been focussed on the effect of sampler design and composition as well as conditions of exposure on the number of systematic units and the biotic index obtained.With artificial substrates correct assessments could be performed in different types of watercourses, including lowland brooks and canals as well as fast running upland rivers located in different climates.Guidelines for the development of a simple standard procedure with artificial substrates are proposed.     

Effects of land use on water quality and aquatic biota of three North Carolina Piedmont streams

Three streams in the Piedmont ecoregion of North Carolina were studied to evaluate the effect of land use (forested, agricultural, urban) on water quality and aquatic biota. In comparison with the forested stream, there were few changes in water quality at the agricultural and urban streams. Suspended-sediment yield was greatest for the urban catchment and least at the forested catchment. Suspended-sediment concentrations during storm events followed this same pattern, but at low-moderate flows suspended-sediment concentrations were greatest at the agricultural site. Most nutrient concentrations were highest at the agricultural site, and the amount of available dissolved nitrogen was elevated at both the urban and agricultural sites. High concentrations of metals (totals) in the water column were sometimes observed at all sites, but maximum average concentrations were recorded at the urban site (especially Cr, Cu, and Pb). Maximum sediment metal concentrations, however, were not found at the urban site, but were usually recorded at the forested site. Only minor differences were noted between fish communities of the forested and agricultural sites, although both abundance and average size of some species increased at the agricultural site. The fish community at the urban site was characterized by low species richness, low biomass, and the absence of intolerant species.Invertebrate taxa richness, a biotic index, and the number of unique invertebrate species (found at only one site) indicated moderate stress (Fair water quality) at the agricultural site and severe stress (Poor water quality) at the urban site. At the agricultural site, declines in taxa richness within intolerant groups were partially offset by increases within tolerant groups. The agricultural stream had the highest abundance values, indicating enrichment. The urban site, however, was characterized by low species richness for most groups and very low abundance values. Analysis of seasonal patterns suggested detritus was the most important food source for invertebrates in the forested stream, while periphyton was of greater importance in the agricultural stream. Dominant macroinvertebrate groups shifted from Ephemeroptera at the forested site, to Chironomidae at the agricultural site, and Oligochaeta at the urban site. There was little between-site overlap in dominant species (8–7%), indicating that land use strongly influenced the invertebrate community. Chemical and physical parameters measured at the three sites did not seem sufficient to account for all of the observed differences in the invertebrate communities, suggesting some unmeasured toxicity. Biological measurements, especially macroinvertebrates community structure, consistently indicated strong between-site differences in water and habitat quality.     

微囊藻毒素对鱼类的毒性效应

湖泊富营养化导致的蓝藻水华已成为国内外普遍关注的环境问题,它所带来的主要危害之一是产生的藻毒素对鱼类的影响。在已发现的藻毒素中,微囊藻毒素(microcystins,MCs)的分布广、毒性大、危害严重,而备受关注。阐述了MCs对鱼类的影响。微囊藻毒素能干扰胚胎的发育,降低孵化率,增加畸形率,影响存活率,胚胎孵化受微囊藻毒素影响还具有剂量依赖效应;野外室内实验均表明鱼类暴露于微囊藻毒素后不仅可在肝脏中富集还可在肌肉、肠道等组织器官中快速积累;对鱼类进行组织病理检测发现MCs可导致肝脏、肾脏、心脏、脑、鳃等组织受损;MCs在鱼体中的解毒过程可能开始于由谷胱甘肽S-转移酶催化的还原型谷胱甘肽的结合反应;MCs还可影响鱼类的生长、行为和血清生化指标,此外,还具有一定的免疫毒性。MCs的转运机制和分子作用机制以及在食物链中传递过程中对人类造成的潜在影响可能成为今后研究重点。