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1.
蛋白分离器对循环水养殖水质理化因子的调控作用   总被引:1,自引:0,他引:1  
通过测定5个关键水质理化因子,研究蛋白分离器对南美白对虾养殖水质的调控作用。结果表明:使用蛋白分离器后,水体的pH值维持在8.0~8.3,养殖水体中氨氮最高达到0.917mg/L,亚硝酸盐最高达到0.324mg/L,DO含量在3.775~6.300mg/L,COD含量峰值为14.27mg/L。  相似文献   

2.
论水域的渔业污染与自净   总被引:15,自引:0,他引:15  
渔业对水环境的污染主要来自人工投饵。增殖和不投饵养鱼则对水质有净化作用。用人工配合饲料每生产1kg鱼,有约800g有机物、70g氮和14g磷通过各种形式进入水体,导致水域富营养化。磷含量是水域污染的敏感性指标。渔业污染的强度和养殖容量成正相关,与水域的容积成负相关。在流动的水体中,则和流量成负相关。当三峡重庆库区网箱养殖规模按渔业水面1‰设定,网箱面积为40hm^2,单产90t,总产5.4万t鱼时,磷污染强度为0.00176mg/L,相当于湖库Ⅱ类水质磷含量指标0.025mg/L的1/15。污染强度为0.1008mg/L。有机物污染将造成三峡水库水域溶解氧量下降0.35~0.5mg/L,相当于三峡水库溶解氧含量指标7.0~10.5mg/L的1/20。当三峡水库重庆库区磷污染控制增量确定为0.0025mg/L时,养殖容量为7.7万t鱼。天然水体的自净作用能有效降低生化需氧量,但不能降低水域的磷、氮浓度。大量放流以白鲢、草鱼、鲤鱼为主的各种鱼类和适量发展不投饵网箱养殖白鲢,是去除水中氮、磷最好的方法。在三峡水库中捕捞和通过不投饵方式养殖5万t鱼类,可消除1500t氮和300t磷,从而降低三峡水库磷含量0.0007mg/L。相当于投饵养殖5.4万t鱼造成磷污染量的40%。  相似文献   

3.
采用循环水工艺高密度养殖南美白对虾的研究   总被引:2,自引:0,他引:2  
2002年7--10月在福建省惠安县开展了采用循环水工艺实施南美白对虾高密度养殖实验,经约90d养殖实验,获得平均产量1.62kg/m^2的收成。结果表明:所设计的循环水道具有实施养殖水沉淀、水质强化处理、隔离进水源病害传染等功能。养殖水体用活菌生物净水剂处理.清除对虾高密度养殖水体中的有机污物,保持水体生态平衡。养殖池水环境有效抑制水中的氮氮含量和异养细菌数。  相似文献   

4.
上海市淡水养殖水体中氮、磷的分布研究   总被引:2,自引:0,他引:2  
为查明上海市淡水养殖水体中氮、磷分布现状,选取上海市典型的淡水养殖场进行引水和池塘水质监测。结果表明,上海市淡水养殖水体中总氮、总磷年均质量浓度分别为2.53 mg/L和0.294mg/L;引水和池塘水体中总氮平均质量浓度无显著差异(P0.05),池塘水中总磷平均质量浓度为0.370mg/L,显著高于引水;不同养殖品种池塘中氮、磷年均质量浓度有所差异,淡水鱼塘中总氮、总磷平均质量浓度最高,凡纳滨对虾塘次之,中华绒螯蟹塘最低;养殖生产使池塘水体中有机态氮、磷在总氮和总磷中的占比以及氨氮在无机氮中的占比较引水均有所增加;引水中总氮在春、冬季含量相对较高,总磷在夏、冬季含量较高。养殖过程中淡水鱼塘中氮、磷含量因有机质的累积在秋季养殖后期较高;凡纳滨对虾塘中氮、磷含量在5月养殖初期相对较高;中华绒螯蟹塘内氮含量因水草的净化作用随养殖进程逐渐降低;70%以上的引水样品水质综合污染指数高于1.0,淡水养殖的引水质量不容乐观。整体上,淡水鱼的养殖显著增加了水体的综合污染程度(P0.05),凡纳滨对虾和中华绒螯蟹的养殖对水体综合污染程度影响不显著(P0.05)。  相似文献   

5.
养殖水体富营养化是现今凡纳滨对虾养殖面临的问题,水体富营养化主要是养殖环境中浮游植物过量生长,深层次的原因是对虾养殖中过量的投饵及高密度的养殖模式等导致水体中氮、磷等元素含量增高,产生一些对对虾有害的水质因子。  相似文献   

6.
20世纪90年代以来,水产养殖业迅猛发展,集约式工业化养殖规模日益扩大。大规模高密度的养殖水体含有大量粪便和残饵,造成水体中氮、磷等营养物质含量持续增高,加上长期的外源负荷造成污染物在水体中大量积累,容易引起严重的内源污染。水体富营养化有许多不良副作用,涉及经济成本等问题。水体一旦形成富营养化就很难彻底恢复。在有效控制外源性污染的同时,  相似文献   

7.
技术交流     
《海洋与渔业》2013,(1):57-57
鳜鱼在养殖过程中由于大量捕食饲料鱼,其排泄物对养殖水体的污染十分严重(尤其在水体底部)。看水养鱼的养殖户看到养殖池水很清,常常以为不用换水。有经验的鳜鱼养殖户发现。水质污染后,鳜鱼往往出现吐食(捕食后又将饵料吐出)、食欲减退甚至不摄食等现象。因为鳜鱼在饱食后对水质的要求比空腹时高,  相似文献   

8.
水产养殖与生态营养   总被引:1,自引:0,他引:1  
随着水产科技水平的不断提高,水产养殖集约化、规模化的迅速发展,在水产品产量大幅度增加的同时,也带来了一系列问题,在集约化、高密度养殖中,残饵和排泄物的数量超过了微生物的分解能力,导致水中氮、磷含量增加,水质恶化,底质污染严重,养殖水体富营养化,最终造成养殖系统物质和能量循环失调,甚至受阻;养殖生物生长变慢,病害加重,死亡率升高,严重影响我国水产养殖业健康、稳定和可持续发展。其中最为突出的就是产生了养殖污染。所谓养殖污染,即指水生动物不断排出的粪便及残饵等废物的增长速度超过了水流的冲刷速度和水体的自净能力,  相似文献   

9.
<正>近20年来,我国水产养殖业迅猛发展,集约化高密度养殖逐渐成为水产养殖的主流,目的是发挥各类有限的水体资源,得到更好的经济效益和产量。人工养殖对水产品生产的贡献日益增大。但是集约化生产在提高经济效益的同时也带来新的问题。在集约化高密度养殖模式下,养殖水体自身污染非常严重,在养殖过程中饵料利用率较低,养殖过程中大量的残饵、生物代谢物、动植物尸体等有机物积累于养殖池底,这些有机物在嫌气细菌的作用下会腐败分解产生大量对水产养殖动物有毒的物质,导致养殖水体的理  相似文献   

10.
高密度鱼虾养殖池水体中残饵、粪便量大,水质易恶化。生物活性水质改良剂能将水体和底泥中的氨氮、硫化氢等有害物质转变为有益物质,从而改良水质,促进鱼虾生长、增产增收。常用的生物活性改良剂有下列6种:1光合细菌高密度鱼虾池水体中所含的大量粪便和残饵,腐败后产生氨态氮、硫化氢等有害物质,污染水体和底质,造成鱼虾生长缓慢甚至中毒死亡。同时,水体富营养化后病原微生物滋生,鱼、虾会感染发病。光合细菌能吸收水体中有毒物质,长成自己有  相似文献   

11.
采用低频率运转循环水处理系统(含粗滤器、臭氧仪、气液混合器,蛋白分离器、暗沉淀池等)联用池内设施(微泡曝气增氧机与净水网)开展凡纳滨对虾室内集约化养殖实验。研究了养虾池以水处理系统调控水质效果及氮磷收支。结果表明,养虾水经系统处理后,NO2-N(53.4%~64.5%)、CODMn(53.4%~94.4%)与TAN(31.6%~40.4%)被显著去除,有效改进虾池水质;养殖周期内未换水与用药,虾池主要水化指标均控制在对虾生长安全范围,7号实验池(100 d)与8号对照池(80 d)主要水化指标变化范围:DO分别为 5.07~6.70 mg/L和4.38~6.94 mg/L,TAN 0.248~0.561 mg/L和0.301~0.794 mg/L,NO2-N 0.019~0.311 mg/L和0.012~0.210 mg/L,CODMn 10.88~21.22 mg/L和11.65~23.34 mg/L。7号池对虾生长指数优于8号池(80 d虾病暴发终止),单位水体产量分别为1.398 kg/m2与0.803 kg/m2。氮磷收支估算结果:7号与8号池饲料氮磷分别占总收入:氮93.70%与92.37%,磷98.77%与99.09%;初始水层与虾苗含氮共占总收入6.30%与7.63%,磷共占1.23%与0.91%。总水层(含排污水)氮磷分别占总输出:氮56.45%与59.86%,磷53.26%与55.79%;收获虾体氮磷分别占总输出:氮37.07%与31.94%,磷21.37%与13.11%。7号池饲料转化率较高;池水渗漏与吸附等共损失氮磷分别占总输出:氮7.00%与9.34%,磷25.37%与31.10%。实验结果表明,虾池以低频率运转循环水处理系统联用池内设施可有效控制水质与虾病,具较高饲料转化率。  相似文献   

12.
A phosphorus budget for a single crop was prepared for a 685‐ha semi‐intensive shrimp farm that consistently has produced about 3000 tonnes/yr of black tiger prawn, Penaeus monodon. Phosphorus inputs were shrimp stock, 0.31 kg/ha; triple superphosphate, 1.38 kg/ha; incoming water, 25.8 kg/ha; and feed, 65.3 kg/ha. Phosphorus outputs were harvested shrimp, 5.43 kg/ha, and outflow for water exchange and draining, 42.7 kg/ha. The high clay‐content soil in pond bottoms adsorbed 45.2 kg/ha of phosphorus. Water was taken from and released back into the same estuary and bay. The phosphorus contribution of shrimp farming to the receiving water body was the difference between the amount of phosphorus in effluent and that in the incoming water, which was 16.9 kg/ha. Bottom soil accumulated 67.8% of phosphorus added to the ponds. Another estimate of soil phosphorus uptake based on the relationship between cumulative phosphorus applied to ponds as fertilizer and feed and soil phosphorus concentration suggested that 63.2% of fertilizer and feed phosphorus had accumulated in pond bottoms. The farm effluent phosphorus load was 23.5 tonnes/yr. The estuary and bay system has an estimated volume of 4.8 × 109 m3, and the annual phosphorus input from the farm had a concentration equivalent of 0.005 mg/L, and there were no other major inputs of phosphorus. The estuary and bay are flushed by freshwater inflow and tidal action, and the farm input is not likely to cause eutrophication.  相似文献   

13.
Production of shrimp in inland ponds supplied by water from saline aquifers is a potential new aquaculture industry in Alabama. Examination of 2,527 well records of the Geological Survey of Alabama and the United States Geological Survey and samples from 35 wells revealed 238 wells with chloride concentration of 125 mg/L chloride or more in 11 counties of central and west-central Alabama. Chloride concentrations varied from 136 mg/L to 94,000 mg/L. The highest chloride concentrations were from wells in Washington, Choctaw, and Clarke Counties. However, 83% of the saline-water wells in Dallas, Hale, Greene, Marengo, Wilcox, and Sumter Counties were supplied by aquifers of the Eutaw, Gordo, McShan, and undifferentiated Eutaw-McShan formations. Water from these wells had an average and standard deviation of 1,238 ± 615 mg/L chloride. Based on the frequency of saline-water wells, the number of wells with chloride concentrations above 700 mg/L (about 2 ppt salinity), and well depths, it was concluded that Hale, Greene, Marengo, and Sumter Counties have the greatest potential for saline-water aquaculture. Contour maps for chloride concentrations and depths of wells in these four counties were prepared to better delineate this potential water source for aquaculture. There were, however, areas in Lowndes, Tuscaloosa, and Wilcox Counties with saline ground water suitable for inland aquaculture.  相似文献   

14.
湛江港沙湾对虾养殖场虾池水质状况分析   总被引:2,自引:0,他引:2  
2002年4~7月,对湛江港沙湾对虾养殖场虾池的水质及对虾的生长情况进行连续监测,应用单项指标评价、富营养化评价等方法,对该养殖场的水质状况进行了评价和营养分级。结果表明,该养殖场的水质呈高N低P状态,水温、DO和大部分池的pH、DRP符合第二类海水水质标准,DIN超标,超标率达70%,该养殖场目前处于P中等限制潜在性富营养水平阶段。  相似文献   

15.
Low‐salinity waters of inland shrimp ponds in Nakhon Nayok, Chachoengsao, Prachin Buri, and Samut Sakhon Provinces of Thailand often had concentrations of potassium and magnesium below those expected for normal seawater diluted to the same salinity. However, in Samut Sakhon Province – where the sampling area was nearer the coast – ponds typically had higher concentrations of these two cations than did ponds in the other three provinces. Studies of inland, shrimp ponds at Banglane in Nakhon Pathom Province revealed that magnesium additions to maintain a target concentration near 100 mg/L resulted in greater (P < 0.05) shrimp survival, size, and production than obtained in control ponds. Although potassium additions to ponds (75 mg/L target concentration) did not improve shrimp survival or production, the control ponds had potassium concentration higher than those previously reported for ponds in Alabama where potassium treatment was highly beneficial to shrimp survival and production. A study conducted using laboratory, soil‐water systems with soil from one site did not remove potassium and magnesium from the water, while soil from two other sites removed potassium and magnesium from water – but at different rates.  相似文献   

16.
对黄河下游利津重盐碱地池塘的水化学进行了分析。结果表明:1.该类水体水型为ClNⅡa,总含盐量899.6~3 336.6 mg/L,在阴离子中,Cl-〉SO24-〉HCO3-+CO32-,其含量分别为703.52 mg/L、302.83 mg/L和167.82 mg/L。阳离子的含量顺序为K++Na+〉1/2 Mg2+〉1/2Ca2+,其含量分别为479.43mg/L、92.21 mg/L、72.29 mg/L。2.各塘总碱度平均值为2.12~4.29 mmol/L,其组成主要是HCO3-碱度;pH为8.37~8.96,极值范围为8.10~10.39;总硬度含量较高,各塘平均在8.08~14.35 mmol/L,极值范围为7.05~17.20 mmol/L;养鱼池塘的Ca2+含量大于Mg2+含量,而养虾池塘Mg2+含量大于Ca2+的含量。3.氮的含量较适合浮游植物的生长,而大部分养虾池塘总磷的含量很低,但养鱼池塘总磷含量相对较高。  相似文献   

17.
Chemical and Physical Properties of Shrimp Pond Bottom Soils in Ecuador   总被引:1,自引:0,他引:1  
Chemical and physical analyses were conducted on bottom soil samples from 74 brackish-water ponds representing 40 shrimp farms in Ecuador. Most ponds had soils with pH > 6 and total carbon concentrations < 2.5%. Carbon was mostly in organic form, for the average concentration of carbonate carbon was 0.06%. The C: N ratio was 8 to 10 in soils with < 2.5% carbon. In ponds built in former mangrove areas, soil carbon was > 2.5% and C: N ratios were 25 to 30. Ponds soils in former mangrove areas also tended to be high in total sulfur and low in pH. Lack of correlation between carbon and sulfur in mangrove soils suggested that most of the sulfur was inorganic and presumably in sulfides. Soils containing above 0.4% free carbonate (as equivalent CaCO3) had pH values > 7. Although carbonate concentration was a major factor controlling soil pH, calcium hardness of pond waters was strongly influenced by salinity (and calcium) in the water supply. Total phosphorus concentrations averaged 898 mg/kg, and dilute acid extractable phosphorus usually accounted for 25–35% of the total. Concentrations of major cations and minor elements varied greatly in soils and exhibited ranges of up to three orders of magnitude. Contrary to opinions of shrimp producers, many pond soils in Ecuador are not acidic and few soils have a high organic matter content. Proper use of soil and water testing could greatly improve the efficiency of liming and other soil management practices.  相似文献   

18.
The industrial aquaculture pond system has gradually replaced the use of traditional earthen pond, as it causes less pollution and is more economical. In this study, an industrial ecological purification recirculating aquaculture system consisting of the water source pond, high‐density culture ponds, a deposit pond, and ecological purification ponds for channel catfish cultivation was established. Twelve water samples from different ponds were sequenced, and the bacterial communities were analysed. The abundances of Cyanobacteria and Merismopedia varied in different functional ponds of the system. The water quality was stable after two months of cultivation at 1.89 ± 0.22 mg/L total nitrogen, 1.1 ± 0.08 mg/L NH4‐N and 0.43 ± 0.1 mg/L total phosphorus. The fish weight increased in a nearly linear manner, reaching 237.63 ± 23.8 per fish at day 120. An analysis of the environmental parameters, water quality and fish weight suggested that the system had an effective water purification process. Canonical correspondence analysis showed that the community was affected at the genus and phylum levels by different environmental parameters. We identified several dominant beneficial bacteria with nutrient removal abilities. Overall, our results demonstrated that the ecological purification recirculating aquaculture system had notable effects on water quality improvement and promoted changes in bacterial populations. These results provide important information on the microbial ecology of pond industrial eco‐aquaculture systems.  相似文献   

19.
Application of readily-oxidizable organic substrate to laboratory soil-water systems and fish ponds caused anaerobic conditions in bottom soil and water, and concentrations of soluble reactive phosphorus (SRP) increased. Aeration of ponds increased total phosphorus (TP) concentrations by suspending soil particles in the water, but SRP concentrations declined because of increased oxy- genation of bottom water and soil, Alum [Al2(SO4)3·14H2O] treatment of ponds reduced SRP and TP concentrations in ponds, but the low concentration of alum used, 20 mg/L, had little residual effect on phosphorus concentration. Application of agricultural limestone at 0.2 kg/m2 to ponds with soil pH of 5.5 and Ca2+ concentration of 5 mg/L did not affect SRP and TP concentration. Unless pond soils were anaerobic at their surfaces, a condition not acceptable in thermally-unstratified fish ponds, soils released little phosphorus to the water. Strong adsorption of phosphorus by soils in intensive ponds with feeding is beneficial, because removal of phosphorus by aerobic soils is a control on excessive phytoplankton growth. In fertilized ponds, phosphorus must be applied at frequent intervals to replace phosphorus removed from the water by soils.  相似文献   

20.
ABSTRACT:   An experiment in which water was circulated between shrimp aquaculture ponds stocked with 10 000 or 20 000 PL-15 stage Penaeus monodon , and mangrove enclosures each planted with 476 Rhizophora mucronata per enclosure, was carried out at the Samut Songkhram Coastal Aquatic Research Station, Faculty of Fisheries, Kasetsart University, Thailand. Shrimp survival rate was significantly higher ( P  < 0.001, Fisher's exact test) in ponds where 10 000 larvae was stocked and water was exchanged with the mangrove enclosure, compared with the control pond with no water exchange, over the 136 day experimental period. Phosphorus transport to the mangrove enclosure was estimated to be 0.41 kgP and 0.18 kgP over the experimental period and change in phosphorus content in mud was reduced there compared with the control pond. A load reduction effect to the environment was confirmed in this aquaculture system with mangrove enclosure compared with the phosphorus budget in the control pond, and 6.2 or 8.9 ha of mangrove area was estimated to be required by 1 ha shrimp ponds to fully process the phosphorus.  相似文献   

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