The Nitrogen Budget of a Tropical Semi-Intensive Freshwater Fish Culture Pond

Nitrogen inputs, outputs and compartamentalization were quantified in a freshwater fish pond stocked with hybrid Oreochromis throughout a production cycle. The budget accounts for 91% of the nitrogen added to the system. Feed addition accounted for 87% of the nitrogen input and an additional 11% was attributable to nitrogen fixation, mainly in the water column. The balance of the nitrogen input was contained in the source water for the pond. Commercial-size fish accumulated 17.5% of the nitrogen added to the system. Most of the nitrogen was eventually deposited in the sediments. Nitrification constituted a major pathway for nitrogen transformation, but only 1% of the nitrogen input was lost through denitrification.     

Vertical Gradients of Organic Matter Concentration and Respiration Rate in Pond Bottom Soils

Abstract.— Total carbon concentration and respiration rate were greater in the upper 0.5-cm or 1.0-cm layers of pond soil than in deeper layers. The respiration rate expressed on either a dry soil weight basis or a soil carbon basis decreased with increasing soil depth. This suggests that the ratio of labile to refractory organic matter also declines with increasing soil depth. Variation in soil properties with depth should be considered in pond bottom soil sampling programs.     

Physical and Chemical Characteristics of Bottom Soil Profiles in Ponds at Auburn, Alabama, USA and a Proposed System for Describing Pond Soil Horizons

Soil cores were taken from each of three, 2-, 23-, and 52-yr-old research ponds (650–1,010 m² area) at Auburn, Alabama. Many physical and chemical variables changed in intensity with increasing depth in cores. Compared to original compacted pond soil, sediment contained more moisture; had lower bulk density (<1.4 g/cm³); possessed higher percentages of silt and clay; had greater porosity, specific surface area, and cation exchange capacity; and contained greater concentrations of organic matter and nutrients. Sediment organic matter was highly decomposed as evidenced by low proportions (5–15%) of carbon and nitrogen associated with the light fraction (soil retained on a 53-μm sieve). Sediment depth at 100-cm water depth increased with pond age (11.7 cm, 28.3 cm, and 48.3 cm in 2-, 23-, and 52-yr-old ponds, respectively), but sediment composition did not change greatly over time. Successive layers in cores were as follows: 1) water near the soil-water interface with a high concentration of solids; 2) high moisture content sediment with dry bulk density <0.3 g/cm³; 3) lower moisture content sediment with bulk density between 0.3 and 0.5–0.7 g/cm³; 4) rapid transition of bulk density from 0.5–0.7 g/cm³ to 1.4 g/cm³; 5) original compacted soil with bulk density of 1.4–1.7 g/cm³. We propose that these five layers be referred to as F (flocculent layer), S (stirred or mixed sediment), M (mature, bulk, un-mixed sediment), T (transitional layer), and P (original, undisturbed pond bottom) horizons, respectively. Superficial, oxidized sediment is termed an S_o horizon, and the reduced part of the S horizon is termed an S_r horizon. The upper part of the T horizon is an MT horizon when it is similar to the M horizon, or a FT horizon when it resembles the P horizon. A system for delineating horizons in pond soil profiles will be valuable in future attempts to classify pond soils.     

循环流水型池塘养鱼生态系统设计与构建

应用农业生态工程学原理,发展利用人工湿地等水质净化技术作为池塘养鱼水质管理策略,通过构建循环流水型池塘养鱼生态系统,建立具有水质保证、无公害和适于健康养殖的池塘结构模式,实现水资源的可持续利用。     

盐碱地池塘配置网箱养鱼试验

在盐碱地一个面积为2871m^2的鱼池中,配置4个网箱．分别放养罗非鱼、淡水白鲳和鲤,箱外放养鲢、草鱼和鲤。试验结果：罗非鱼箱(20m^2)出鱼525kg．平均单产26．3kg／m^2,淡水白鲳箱(12m^2)出鱼400kg,平均单产33.3kg／m^2,鲤鱼箱两个(各12m^2)分别出鱼488．5kg和522kg,平均单产为40．7kg／m^2和43．5kg／m^2。箱外出鲢516kg,草鱼130kg,鲤1125kg。总计全池出鱼3706．5kg,亩产鱼862kg,每亩纯盈利2173．85元。试验证明：池塘配置网箱养鱼．可同池主养几种鱼,起捕容易,管理方便。     

海蜇的池塘养殖技术

海蜇的营养十分丰富，含蛋白质12．3％，脂肪0．1％，糖类4％，还含有很多铁、钙、磷和大量维生素。海蜇体内含水分很多，通常用盐、矾加工成海蜇皮和海蜇头，成为人们喜爱的水产食品。     

城郊垂钓池塘养鱼技术初步研究

详细介绍了鱼池的选择与建设、配套设施、鱼类放养、饲养管理和病害防治等。池塘要选在离市区较近、交通方便的地方,环境应设计为封闭式的小生境,垂钓品种以鲫为主,搭配放养鲢、鳙、鳜等,池鱼密度冬季为1．5万～7．5万kg／hm^2。春秋季为1．5万～6万kg／hm^2,夏季为1．5万～3．75万kg／hm^2。饲养管理同池塘养鱼。     

Sedimentation and Resuspension in Earthen Fish Ponds

Resuspension of particles from pond sediment into the water column may be an important nutrient transfer mechanism in aquaculture ponds. However, the magnitude of sediment re-suspension cannot be determined directly because sediment traps collect particles settling from the water column as well as those re-suspended from the pond bottom. We developed a dilution analysis method to differentiate the magnitude of the two particle source fluxes based upon the concentration of soil-derived elements (Si, Al, and Fe) and water-derived elements (C, N) in material collected by sediment traps placed in earthen ponds. Estimated organic C sedimentation from feed residues and algae was compared with trapped organic C as an independent and approximate measure of resuspension. Resuspension fluxes based independently on analyses of three soil-derived elements and on the estimation of expected C sedimentation were similar and accounted for 60–90% of the total solids flux (121–2,676 g/m² per d) in most ponds sampled. The proportion of total flux that was derived from resuspension in ponds stocked with common carp Cyprinus carpio and tilapia Oreochromis spp . was modeled as a hyperbolic function of fish size and density, with a threshold fish size of 200–300 g. Resuspension flux was conservatively estimated to be equivalent to the daily suspension of a few mm of the pond bottom. These results indicate that sediment resuspension is a major process in carp and tilapia ponds, suggesting that the exchange of nutrients between the sediment and overlying water is intensive.     

Potassium Adsorption by Bottom Soils in Ponds for Inland Culture of Marine Shrimp in Alabama

Potassium is applied to correct ionic imbalance in pond water for inland culture of marine shrimp in Alabama. This study evaluated the loss of potassium through adsorption by bottom soil. Adsorption by bottom soils of potassium added in fertilizers continued over 4 yr. Exchangeable potassium concentration in bottom soils did not increase after the first year, but potassium loss to bottom soil continued over 4 yr. Laboratory work on soil–water systems contacted bottom soil with potassium‐enriched pond water for 8 mo: nonexchangeable potassium fixation accounted for 75% of potassium adsorption. Soil total potassium adsorption averaged 518 mg/kg. Bottom soil samples exposed to consecutive 50 mg/L potassium solutions (potassium chloride in distilled water) and agitated by shaker led potassium adsorption by soil to decline from 406 mg/kg in first exposure to 70 mg/kg in sixth exposure. During the next six exposures, potassium adsorption was similar, between 61 and 95 mg/kg in each exposure, averaging 1804 mg/kg of potassium. Pond soils contain smectite clay, have a large capacity to adsorb potassium by nonexchange processes, and remove added potassium from water for years. The only reliable way to determine when potassium fertilizer may be added to Alabama inland shrimp ponds is to monitor potassium concentration in water.     

池塘网箱养鱼的可行性及技术研究

１９９５、１９９６年在精养成鱼塘设置网箱养殖商品湘鲫与乌鳢鱼种，采取灌排水形成微流、启动增氧机、投放耐低氧吃食性鱼类、投喂颗粒馈料和动物肉、勤刷钢箱养措施，结果：湘鲫养殖１３６天，从１５０ｇ长到６７０ｇ，平均日增重３．８２ｇ，２５ｍ＾２的网箱产成鱼３３４．３３ｋｇ。平均１３．３ｋｇ／ｍ＾２，成活率９９．８％，乌鳢种培育４２天，由体长１ｃｍ到１０ｃｍ，平均日增长２．１４ｍｍ，２０ｍ＾２的网箱，共育鱼     

略论池塘养鱼无公害产品生产中de几项关键性措施

随着人们生活水平和生活质量的提高，以及参与国际贸易的需要，水产养殖产品的质量安全倍受关注，池塘养鱼必须实施无公害生产。作者认为，池塘养鱼无公害生产应抓好以下几项环节：选择好养殖基地的环境，建造独立的进排水系统，挖除过多淤泥和管理好水质，使用无公害鱼饲料，强化生态防病等。     

池塘网箱养殖乌鳢试验

在宿鸭湖水库管理局水产试验场进行了池塘网箱养殖乌鳢试验。试验池面积16亩,设置6×11×2米单层聚乙烯网箱13只,箱内放乌鳢种3.2万尾,池内放其它鱼类21600尾,至年底共收获乌鳢31468.7公斤,其它鱼类12157.2万公斤,产值47.5万元,利润27万元,投入产出比1∶2.3。     

池塘养鱼大面积大幅度增产技术试验

１９９５～１９９６年,在山东省茌平县和东昌府区进行了大面积养鱼增产试验。通过小池改大池,浅池改深池,投放大规格鱼种,合理密养,施肥投饵,防治鱼病,建立技术网络等措施２５２９９亩鱼池,共产商品鱼８９２５４８７．２ｋｇ,平均每亩净产３５２．８ｋｇ,商品率９０％,平均每亩盈利１５１２元,投入产出比１：２．１８,验收鉴定认为,增产幅度达省内领先水平。     

池塘养鱼高产优质高效目标管理模式

池塘养鱼生产经营效益关系到产业自身的巩固和发展,作者经过多年的生产,科研和调查研究,并在１９９－１９９３年以上海市淀山湖联营养殖场为试点,探索池塘养鱼高效益管理模式,归纳为“一个目标,二个保证,三种动力”的“１－２－３管理模式”。具体实施后,淀山湖联营养殖场１９９３年获池塘养鱼每公顷净产１１５６５公斤,每个职工平均产值达４２３７５．３２元,实现了高产,优质,高效益的管理目标。     

池塘养鱼大面积高产技术推广试验

在总面积为２１６５ｈｍ＾３的池塘中，试验推广４种养鱼模式，池塘设置小网箱等技术，取得大面积高产结果：平均亩产６５２９．５ｋｇ／ｈｍ＾２，平均盈利１２０１０．５／ｈｍ＾２，比推广前３年平均亩产提高５５．９％，鉴定认为，在养殖面积，单产水平及综合管理技术等方面达我国北方同类水域的先进水平。     

高温季节鳜及饵料鱼池塘浮游生物调查研究

于高温多雨季节对广东省清远市鳜养殖基地的6个鳜（Siniperca chuatsi）及饵料鱼养殖池塘发病前后的浮游生物组成进行了调查分析。结果表明,易发病池塘,水中浮游生物总生物量比其他池塘略低。浮游植物优势种均为微囊藻（Microcystis sp.）,颤藻（Oscillatoria sp）等蓝藻。此外,池塘出现出血病症状时,浮游生物的马格利夫（Margalef）丰度指数和香农（Shannon-weaver）多样性指数均处于较低水平,这两项指数可作为池塘发病的预警参考指标。在实际生产中,平时应注意调节水质,以稳定水中浮游生物的数量和组成,在天气不佳时更应多加巡塘,以便及早发现病情。     

主养草鱼池塘3种混养模式鱼类生长和效益比较

为进一步提高池塘养鱼的产品质量和经济效益,改善养殖生态环境,在武汉新洲973项目实验基地的9个陆基鱼池中,对主养草鱼的3种不同混养模式鱼类生长和效益进行了比较研究.模式Ⅰ放养草鱼、鲢、鳙和高背鲫,模式Ⅱ放养草鱼、鲢、鳙、匙吻鲟和高背鲫,模式Ⅲ放养草鱼、鲢、匙吻鲟和高背鲫.通过122 d的养殖试验,模式Ⅱ草鱼的生长不仅显著高于模式Ⅰ和模式Ⅲ(P＜0.05);经济效益对比分析发现,模式Ⅱ同样高于模式Ⅰ和模式Ⅲ.     

主养草鱼池塘三种混养模式鱼类生长和效益的比较

为进一步提高我国广大池塘养鱼的产品质量、经济效益和改善其生态环境。本试验在武汉新洲973项目实验基地9个陆基鱼池中进行了三种不同混养模式鱼类生长和效益的比较研究,每种模式设3个重复。模式Ⅰ中放养草鱼、鲢、鳙和高背鲫;模式Ⅱ中放养草鱼、鲢、鳙、匙吻鲟和高背鲫;模式Ⅲ中放养草鱼、鲢和高背鲫。 结果表明：通过122d的养殖试验,模式Ⅱ中草鱼的生长不仅显著高于模式Ⅰ和模式Ⅲ（P<0.05）,而且其经济效益模式Ⅱ同样高于模式Ⅰ和模式Ⅲ。