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《渔业现代化》2021,(4)
为探明集中连片池塘排放尾水中氮磷经尾水处理系统各净化功能区的削减状况,分析尾水处理系统氮磷的削减机制,比较论证养殖尾水在各净化功能区的季节、月份变化规律,建立了一个具有养殖尾水处理系统的集中连片池塘养殖小区,对总氮(TN)和总磷(TP)在养殖试验周期内开展持续的时空监测。结果显示:生态沟渠和湿地+净化池塘组合构成的养殖尾水处理系统,6~10月间,对养殖尾水TN显著削减43.02%,TP显著削减30.39%。养殖小区排放水TN(1.318±0.408 mg/L)、TP(0.325±0.160 mg/L)符合SC/T 9101—2007《淡水池塘养殖水排放要求》一级排放标准。夏秋季与沿程交互作用对TN有显著影响(P0.05),夏秋季与沿程对TP不存在交互效应,夏秋季对TP的主效应差异不显著(P0.05)。研究表明:湿地+净化池塘组合对TN的净化效果优于生态沟渠,生态沟渠是TP的主要净化功能单元,养殖尾水处理系统秋季对TN的削减优于夏季。 相似文献
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在河蟹循环水养殖模式中,进行4种不同净化工艺对池塘养殖尾水净化效果的比较研究.工艺1以水生植物为主体进行净化;工艺2以水生动、植物进行多极净化;工艺3以浮萍和金鱼藻等进行净化;工艺4以微生态制剂和金鱼藻等进行净化.分别计算各净化区的污染物净化总量和单位净化面积的净化强度.结果表明,4种不同净化工艺对排入的池塘养殖尾水营养盐均有较好的吸收效果.不同的净化工艺对NH3-N、TN、TP和CODMn的去除能力表现出一定差异.工艺3对池塘养殖尾水中NH3-N、TN和TP的去除效果相对较好,对池塘养殖尾水中氮磷的净化效率相对优于其他3种净化工艺. 相似文献
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潜流湿地净化技术对池塘循环水养殖系统浮游植物群落变化的影响 总被引:1,自引:0,他引:1
构建"潜流湿地+生态池"的湿地生态系统,并以纯生态池净化系统作为对照区,对实验区与对照区内的浮游植物群落结构进行分析,评价该系统的运行效果。结果表明:循环水养殖工程正式运行后,体系中的养殖池塘浮游植物种类数由多到少的顺序为养殖池塘(对照区)养殖池塘(实验区)外河。养殖池塘的浮游植物密度、生物量及生物多样性指数高于外河。经过3级净化后水体浮游植物种类由高到低的顺序为外河净化系统(对照区)净化系统(实验区),密度与生物量迅速下降。生物多样性指数也低于外河,但随着运行时间的增加,其生物多样性指数持续增加。同时,实验区浮游植物多样性均小于对照区,水体营养盐去除更彻底,水质净化效率更高。 相似文献
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The variation of virulence of Renibacterium salmoninarum , the causative agent of bacterial kidney disease (BKD) in salmonid fish, was studied by infecting rainbow trout, Oncorhynchus mykiss (Walbaum), with two isolates (strains 325 and 932) from diseased Atlantic salmon, Salmo salar L., and one isolate (strain 4366) from an apparently healthy Atlantic salmon. Coho salmon, Oncorhynchus kisutch (Walbaum), were injected with the strain 932 to estimate difference in fish species resistance. Fish were removed by random sampling for other study purposes, a study design possible with analysis of lifetime distributions incorporating both sampling-, death- and survival-times. At the end of the experiment, the rainbow trout infected with strains 325, 932 and 4366 had a survival probability of 33%, 51% and 72%, respectively. The coho salmon infected with strain 932 had a 26% survival probability. The strain differences were significant according to the log-rank test, and the risk ratio between the strains ranged from 1·8 to 5·4. The strain from the apparently healthy fish was least virulent. The survival of the fish species was different over time. Rainbow trout were more likely to die early in the time course, but high numbers of coho died later, resulting in an overall risk of mortality of 1·4 in favour of rainbow trout. Differences in virulence may reflect changed selective pressure on R. salmoninarum when introduced from feral stocks into the environment of fish farms. 相似文献
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水硬度对七彩神仙鱼幼鱼发育的影响 总被引:4,自引:0,他引:4
采用不同硬度的水对七彩神仙鱼幼鱼进行饲养。6周龄幼鱼在硬度为7.94°dH±0.30°dH时饲养84d后,比在硬度为14.71°dH±0.23°dH水中的幼鱼个体大,生长速度快。表明较高硬度的水有利于七彩神仙鱼幼鱼的生长发育。 相似文献
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《水生生物资源》2003,16(5):461-465
Anti-proteinase activity was demonstrated in the seminal plasma of cyprinid fish species (bream, chub, ide, dace, asp, goldfish, roach, common carp) using electrophoretic techniques combined with a detection method based on inhibition of bovine trypsin. We found species-specific protease inhibitors in the seminal plasma of cyprinids. At least three bands of protease inhibitors with different migration rates could be identified by native PAGE. Higher variability was characterized for bands with slower migration rates. Visualization of inhibitors after SDS-PAGE under non-reducing conditions allowed estimation of their molecular weights. Apparent molecular weights were within the range of 51–59 and 47–54 kDa for the bands with slower and moderate migration rates, respectively. The molecular weight of fast migration bands for roach and common carp were estimated to 23 and 30 kDa, respectively. Inhibitors of common carp seminal plasma differed in their affinity toward serine proteases. Three inhibitors in common carp seminal plasma could be visualized using cod and bovine trypsin, but only two inhibitors (of high molecular weight) were recognized with chymotrypsin. There were differences in anti-proteinase activity and seminal plasma protein concentration in relation to the origin of common carp seminal plasma (breeding lines) and time of milt collection (spawning vs. post-spawning season). 相似文献
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牙鲆刺激隐核虫病的防治 总被引:1,自引:0,他引:1
2005年七、八月份,乐亭、滦南一带多家工厂化牙鲆养殖场发生刺激隐核虫病,此种病虫害发病急、传染快、死亡率高。发生过该病的养殖场牙鲆死亡率一般都在50%~80%之间,这种病害给牙鲆养殖业带来很大损失。 相似文献
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该研究通过肉眼观察、镜检,进行干露、饥饿、盐度突降、福尔马林等抗性试验,并采用病毒检测等方法,以期建立评估斑节对虾(Penaeus monodon)虾苗活力和质量标准。结果表明,斑节对虾健康虾苗具有趋光性、集群性,体表光洁,肌肉透亮,肠胃食物充盈等特性。测试虾苗干露时间以15min为宜,健康虾苗干露后能立即恢复活力,而病弱虾苗多出现死亡、昏迷现象;虾苗的成活率随饥饿时间的延长而降低,随福尔马林浓度升高和时间延长而降低,随盐度突降幅度增加而降低。健康虾苗能忍受100~200μL·L^-1福尔马林溶液30min,成活率近100%;在盐度20~30下虾苗的成活情况较好,而其在淡水中仅能存活1h。对虾苗进行病毒检测,可以避免养殖中因虾苗携带病毒而可能导致的病毒性疾病的暴发。 相似文献
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鳟鱼发眼卵和旨种运输是养鳟生产的重要环节。发眼卵多在冬季和早春运输,苗种多在晚春和夏季运输。苗种运输大多以鱼篓充氧进行短距离汽车运输,长途运输冷水性鱼苗种的实例很少。本文总结了金鳟和虹鳟苗种长途运输方法,以期与养鳟业界共同交流提高。一、包装材料和方法内包装材料是苗种运输专用塑料袋,规格54×104cm,外包装是泡沫塑料箱,规格63.5×45.5×30.5cm,纸箱规格64×46×32.5cm。塑料袋采取双层式,内装苗种和水共12.5kg,其中苗种0.5-1.3kg,100-2000尾。起运前苗种停食1-2天。运鱼用水水温调至6℃,鱼、水入袋后袋内… 相似文献
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猪的胎盘属于弥散型胎盘,这种胎盘的结构特点和饲养管理的不当,常常导致母猪胎衣不下发生,给生猪的生产繁殖带来极大损失。本文针对母猪胎衣不下发生病因、综合防治进行详细阐述,旨在对预防和治疗胎衣不下能有所帮助。 相似文献
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七种甲壳类水产品脂肪酸组成的分析研究 总被引:5,自引:0,他引:5
水产动物食品中富含ω—3型多稀酸,其中尤其是C_(20:5)(EPA)和C_(22:6)(DHA)对人体有特殊保健功能。本文对七种常见的甲壳类水产品进行脂肪酸组成分析,它们是中国对虾、日本沼虾、安氏白虾、克氏原螫虾、葛氏长臂虾、中华绒螯蟹和三寺疣梭子蟹。测定主要采用黄志斌、李淡秋(1990)的“快速制备脂肪酸甲酯用于气相色谱分析”一文所提供的方法。结果显示,被测样品中不饱和脂肪酸含量高于饱和脂肪酸,而不饱和脂肪酸中多烯酸含量高达60%,且以长碳链(C_(20)、C_(22))ω—3型为特征,表明甲壳类水产品体脂中EPA和DHA含量甚高,超过淡水鱼的一倍,但略逊于海水鱼。值得注意的是,甲壳类水产品中EPA的含量高于DHA的含量,这与鱼类中的情况正好相反。 相似文献