综合养鱼高产池塘的溶氧变化周期

根据1979—1984年对主养鲢、鳙、非鲫,主养青、草鱼,主养青鱼3种养殖结构类型高产鱼池溶氧变化周期的系统研究,揭示了高产养鱼池塘溶氧的昼夜、垂直、水平变化及季节变化周期,分析了光合作用、呼吸作用、扩散作用在高产养鱼池塘溶氧动力学上的地位和作用。对高产养鱼池塘的溶氧收入、支出及平衡情况进行了定量研究,在主要饲养季节,测得晴到多云天、晴天的溶氧来源分别为:浮游植物光合产氧占86.0和95.3%,大气扩散溶入占14.0和4.7%;氧的消耗分别为:“水呼吸”消耗氧占72.0和72.0%,鱼类呼吸消耗氧占22.0和13.1%,淤泥中生物呼吸消耗氧占2.9、5.5%,扩散逸出占3.1、8.8%。文中还对溶氧变化周期与养鱼池塘管理的环境控制、结构控制之间的关系进行了分析。       

主养青鱼高产池塘的初级生产力及其能量转化为鲢、鳙产量的效率

本文论述了主养青鱼高产池塘浮游植物初级生产力的测定结果,揭示了其垂直、季节变化及其与主要生态因子、鱼产量水平、鲢、鳙鱼产量的关系,分析了D/B、P_G/R_W、N/P的作用。研究查明:1米以上水柱的光合产氧量占水柱总产氧量的90％以上。水柱日毛产氧量变动在5.00—17.04克氧/平方米·日之间,水柱年产氧量达2063—2814克氧/平方米·年。初级生产量全年只有一个高峰,常出现在7—8月。主养青鱼型年净产鱼量7500、11250、15000公斤/公顷级池塘的浮游植物鲜重净产量分别为100 674.4、118 560、128 197.6公斤/公顷·年,青鱼、草鱼并重型年净产鱼量15000公斤/公顷级池塘的浮游植物鲜重净产量为137 323.2公斤/公顷·年。 4—11月,毛初级生产力对太阳辐射能的利用率为0.81—1.11％;鲢、鳙产量对浮游植物净产量的直接利用率为3.49—5.13％;太阳能转移为鱼产量的生态学效率为0.028—0.055％。     

人工饵料对主养黄颡鱼和主养草鱼池塘沉降颗粒有机质贡献的同位素示踪

研究假定池塘中沉降颗粒有机质主要来自残饵、粪便和悬浮颗粒物三种的混合, 利用碳氮稳定性同位素示踪技术对主养草鱼（Ctenopharyngodon idellus）和主养黄颡鱼（Pelteobaggrus fulvidraco）池塘沉降颗粒中人为有机质（残饵）来源进行定量研究, 同时分析了不同主养模式池塘沉降颗粒中碳氮营养物质的变化特征。结果表明: 两种主养模式池塘沉降颗粒中总氮（Total nitrogen, TN）、总碳（Total carbon, TC）、总有机碳（Total organic carbon, TOC）以及总有机氮（Total organic nitrogen, TON）都呈现出从养殖初期到末期逐渐降低的趋势; 并且主养黄颡鱼池塘颗粒沉降物中TN、TC、TON和TOC含量均显著高于主养草鱼池塘。主养黄颡鱼池塘沉降颗粒有机质碳氮稳定性同位素（13C和15N）平均值分别为-25.3和6.2; 主养草鱼池塘沉降颗粒有机质13C和15N的平均值分别为-25.4和5.9。利用同位素混合模型计算出两种主养模式池塘沉降颗粒中人为有机质（残饵）贡献率分别为15.6%-35.4%（主养黄颡鱼池塘）和30.1%-70.1%（主养草鱼池塘）, 统计分析结果表明, 两种主养模式池塘从养殖初期到末期沉降颗粒中饵料贡献率均显著降低（主养黄颡鱼池塘: r=-0.537,P0.05; 主养草鱼池塘: r= -0.800, P0.01）。       

微孔增氧技术在黄颡鱼高效养殖中的应用试验

应用微孔增氧技术,能够有效促进鱼池表层和中下层水体交换,在增加水体溶氧的同时,提高了规格及品质,增加了黄颡鱼的产量,效果明显优于传统的叶轮式增氧机,适宜在水产精养池塘中推广应用。     

越冬池冰下生物增氧的一个氧气平衡模式

本文根据实测数据回归得到的经验关系式,结合一定的假设及理论关系式,推导得到一个可供鱼呼吸耗用的氧气量(Rf)与浮游植物现存生物量(B)及有效水深(L)的关系式Rf=f(B,L),并利用此式作了进一步的探讨,求出了越冬池生物增氧的最适水深、最适浮游植物现存生物量及最大越冬鱼密度。提出了一个典型的越冬池生物增氧的模式。       

发酵有机肥对主养草鱼池塘水质调控效果研究

在草鱼(Ctenopharyngodon idellus)主养池塘中,对比检测了发酵有机肥实验塘与未施肥对照塘水质理化指标、浮游生物及微生物群落结构差异,以分析发酵有机肥肥效及其对池塘水环境产生的影响。结果如下:发酵有机肥显著提高了浮游生物种类数、生物量和细菌丰度,增加了浮游植物多样性;实验期间,实验塘浮游植物、浮游动物平均生物量和细菌平均丰度分别为(68.21±25.13)mg/L、(9.83±5.74)mg/L和(6.53±2.13)×10~6 ind./mL,分别是对照塘的2.78倍、4.35倍和1.29倍;发酵有机肥促进有益菌增殖作用显著,施肥后期,实验塘乳酸菌、芽孢杆菌和节杆菌属相对比例分别为(0.61±0.17)%、(0.89±0.29)%和(0.04±0.0082)%,分别是对照塘的3倍、3倍和4倍;发酵有机肥平抑NH_4~+-N、NO_2-N效果显著,在NH_4~+-N、NO_2~--N快速积累季节,实验塘NH_4~+-N、NO_2~--N浓度均显著低于对照塘(P0.05);发酵有机肥增氧效果显著,而对pH、TN、TP、NO_3~--N、PO_4~(3-)-P等无显著影响。研究结果表明,发酵有机肥肥效突出,具有显著改善池塘水环境作用。     

低溶氧量对怀头鲇呼吸代谢耗氧率的影响

在 ( 2 2± 1 )℃下 ,测定了怀头鲇在不同低溶氧量 (DO)时的摄氧量 (VO2 )和呼吸参数。结果表明 ,随着吸入水氧分压 (PiO2 )的降低 ,呼吸频率 (Fr)和VO2 略增 ;鳃通量 (Vg)和呼吸量 (Vb)显著增加 ;而氧利用率 (EO2 )则显著降低。在通常氧含量 ( 7 4 1mg L)时 ,怀头鲇呼吸代谢耗氧率 (Cr)仅为 2 6 3% ,但在严重缺氧 ( 2 5 8mg L)时 ,Cr 则增至 2 4 6 0 %。可见 ,低氧环境将严重抑制怀头鲇的生长。     

水体低氧对香鱼幼鱼生长和消化酶活性的影响

水体溶氧量是影响鱼类的重要环境因子,本研究检测了不同水平的低溶氧胁迫对香鱼幼鱼生长和消化酶活性的影响。结果显示:低氧胁迫后香鱼幼鱼生长受到抑制,溶氧量分别为4.5 mg/L和3.0 mg/L的两组实验鱼在胁迫7 d、14 d和21 d时的体重均显著小于溶氧量为7.5 mg/L的对照组(P0.05),其中胁迫21 d时两组实验鱼的体重分别比对照组鱼的体重轻10.89%和20.73%;胁迫0～7 d期间两个实验组鱼的体重均为负增长(增重率分别为-2.30%、-4.78%),而对照组鱼的体重为正增长(增重率21.31%);胁迫7 d后两个实验组的鱼均恢复生长,且7～14 d期间的体重增重率均大于对照组,表现为补偿性生长;胁迫14～21 d期间溶氧4.5 mg/L的实验组的增重率与对照组相当,溶氧3.0 mg/L的实验组的增重率则略低于对照组。此外,低氧胁迫下两个实验组的淀粉酶、胃蛋白酶、脂肪酶活性均较对照组显著降低(P0.05),而胰蛋白酶活性与对照组差异不显著(P0.05)。其中,胃蛋白酶活性受低氧影响最大,胁迫21 d时两个实验组的胃蛋白酶活性分别仅为对照组的58.40%、62.34%,而淀粉酶活性已恢复至与对照组相当的水平,脂肪酶活性也有所恢复。由此表明,低氧胁迫会降低香鱼幼鱼消化酶活性,阻碍鱼体生长,同时鱼体对低氧环境也有一定的适应性,表现为在低氧环境下生活一段时间后消化酶活性有所恢复,鱼体出现一定程度的补偿性生长。     

越冬池冰下水体理化因子的研究

1.越冬池底层水温一般为1—3.5℃,2月份最低(平均1.03℃)。采用扬水曝气,水温低于0.5℃。 2.明冰下的光照达数千以至上万lx的一般一天有6—7小时以上。乌冰下的光照亦可达3×10~3lx以上,仍有较大的产氧潜力。 3.明冰下的光合作用日产氧量为0.21—12.45,平均2.34±2.11毫克氧/升·日。补偿深度平均为1.13±0.35米。底泥耗氧率平均为0.40克/米~2·日;水呼吸耗氧率为0.04—3.76,平均0.62±0.52毫克/升·日。 4.铵氮各池平均值在0.05—1.29毫克/升总平均0.19(1979年)及0.54(1980年)。硝酸氮各池平均值多在0.1毫克/升以下。亚硝酸氮含量很低,最高0.013,平均0.0027毫克/升。磷酸盐含量平均为0.049(1979年)和0.040(1980年)毫克P/升。 5.发现了冰下表层有对藻类的光抑制和营养盐对光合作用的限制现象。试用冰下施无机肥以提高光合作用速率,效果很好。     

水蕹菜浮床对草鱼主养池塘轮虫群落结构的影响简

研究了水蕹菜浮床对草鱼主养池塘轮虫群落结构的影响,共检出轮虫38种,隶属于2纲14属,其中浮床池塘出现轮虫36种,而非浮床池塘28种。浮床池塘与非浮床池塘的优势种组成基本类似,萼花臂尾轮虫(Brachionus calyciflorus)、裂足臂尾轮虫(Brachionus diversicornis)、裂痕龟纹轮虫(Anuraeopsis fissa)、暗小异尾轮虫(Trichocerca pusilla)以及长肢多肢轮虫(Polyarthra dolichoptera)为共有优势种;浮床池塘与非浮床池塘的轮虫平均密度分别为1892和2255 ind./L,差异极显著(P0.01);浮床池塘与非浮床池塘轮虫平均生物量分别为1.535和1.405 mg/L,差异不显著(P0.05)。结果表明,水蕹菜浮床显著促进了轮虫种类数增加,提高了轮虫多样性和均匀度,并在一定程度上减缓了轮虫小型化。     

Growth and food habits of hybrid carp, Ctenopharyngodon idella×Aristichthys nobilis, from aerated and non- aerated ponds

Hybrid grass carp fry ( Ctenopharyngodon idella × Aristichthys nobilis ) were stocked into 0·04 ha ponds with and without paddlewheel aeration. Fish in the paddlewheel and non-paddlewheel pond, preyed upon identical organisms, but in different proportions. Fish in the paddlewheel ponds grew at significantly greater rates.     

Evolving water quality in a common carp and blue tilapia high production pond

Intensive polyculture of blue tilapia, Oreochromis aureus, and common carp, Cyprinus carpio was conducted to determine their growth capacity and the accompanying water quality transitions in a 376 m² (207 m³) fish pond without aeration or water exchange. A total of 485 fingerlings (290 tilapia and 195 carp) averaging 72 g each (total 35 kg) was stocked and fed commercial floating pellets (36% protein-6%-N) at the approximate daily rate of 3% of the fish biomass six days each week. The total net fish growth was 159.4 kg (4.2 t ha^–1) with an average growth of 199.5 g per fish through the 96 days feeding period — 6 June to 7 September 1984. The s conversion ratio for the commercial feed was 1.3.Physiochemical patterns in the pond water were directly related to the rise and fall of turbidity through the course of the production trial. During one period of low turbidity, a biological inversion was evident with pH and dissolved oxygen measured at higher levels near the pond bottom and increasingly lower toward the surface. It is postulated that settled phytoplankton formed a photosynthetically-active algal mat on the pond bottom. The implications for potential fish kills can be significant.     

The Effects of Periphyton, Fish and Fertilizer Dose on Biological Processes Affecting Water Quality in Earthen Fish Ponds

The potential of periphyton-based aquaculture in South Asia is under investigation in an extensive research program. This paper is a further analysis of data from four experiments carried out in that framework, to explore periphyton, fish and fertilizer dose effects on water quality. Factor analysis and ANOVA models applied to a data matrix of water quality parameters in ponds with and without artificial substrates (bamboo poles and kanchi sticks), with and without fish (filter feeders catla and rohu, with and without bottom feeder kalbaush), and with a standard or 50% increased fertilizer dose, allowed us to identify the underlying ecological processes governing this novel periphyton-based pond system, and construct conceptual graphic models of the periphyton–environment relationships observed. We clearly established that the phosphorus flow is mainly linked to phytoplankton activity in the water column and decomposition on the pond bottom, while nitrogen flow is mainly linked to autotrophic (photosynthesis) and heterotrophic (decomposition and nitrification) processes that take place in the periphyton in addition to the water column and pond bottom. Consequently, disruption of the pond bottom by bottom feeding fish primarily promoted phosphate cycling and phytoplankton, while periphyton development on the supplied substrates and fertilization mainly improved oxygen balance and nitrogen related processes developing in the water column. The use of bamboo poles led to better results than kanchi sticks, related to the greater autotrophic periphyton development on bamboo and to the larger surface of bamboo poles that facilitate fish grazing and periphyton dislodgment that in turn have a renewal effect on periphyton. Stocking bottom feeding fish produces a fertilizing effect through the food web that benefits the filter-feeding fish and that makes it unnecessary to increase the dose of inorganic and organic fertilizers applied to the ponds. Thus, the output of this analysis will help the fish farmers in resource constrained countries to improve their production in periphyton-based ponds just by choosing bamboo substrates, stocking a bottom feeder fish together with the filter feeders, and saving money on fertilizers.     

Species richness of aquatic macrophyte communites in Central Canada

Aquatic macrophyte species richness (SR) was examined at 430 sites in the central Canadian region in relation to water body type, bottom substrate and 8 water chemistry parameters. SR was highest in rivers and lakes, intermediate in creeks, and lowest in ponds. The highest values occurred where granitic bedrock, highly organic substrates or sand predominated. SR was significantly inversely correlated in the study area as a whole with 7 of the water chemistry parameters; of these, total alkalinity was the most important. However, the relative importance of the respective parameters differed for various water body types. The relationship between SR and phosphorus was positive in ponds, but negative for all other water body types. Stepwise sultiple regression analysis identified phosphorus, total alkalinity and dissolved organic matter as important factors in ponds; sulphate, total alkalinity and chloride in lakes, and sulphate and phosphorus in lotic habitats. Log transformations improved the correlations for some variables. However, the water chemistry parameters examined accounted for less than half of the total variability in SR. Apparently SR depends on many different factors, including surface areaand bottom type, whose relative contributions vary with situation.     

Effect of young-of-the-year walleye (Percidae: Stizostedion vitreum) on plankton dynamics and water quality in ponds

To understand the impact of young-of-the-year (YOY) fish on food web dynamics and water quality, we stocked larval walleye (9 mm TL) (Stizostedion vitreum) in six experimental ponds using two fish densities (10 and 50 fish m^–3) with three replicates. At high fish density, the average abundances of cladocerans and copepods and the Secchi depth were lower whereas abundances of rotifers and algae, gross primary productivity (GPP), pH and total phosphorus concentration were higher than at low fish density. Fish impact on bacterial abundance, dissolved oxygen, nitrogen and phosphorus concentrations, however, was not significant. The within treatment measurements of all variables except GPP were significantly different over time. Our results indicate that YOY walleye predation at high density can affect plankton community by reducing large zooplankton biomass and water clarity, and increasing phytoplankton abundance. The impact of YOY piscivorous fish on plankton should be considered when biomanipulation is applied for improvement of water quality.     

应用矿物盐改良池塘水质的研究

为了研究矿物盐对淡水养殖池塘水质的改良效果及应用前景,在12口土质池塘中对淡水养殖斑点叉尾鲴(Ictalurus punctatus Rafinesque,1818)施用三组矿物盐:NaNO3、KCl+MgCl2、NaNO3+KCl+MgCl3的对照实验,对照组池塘不施用任何矿物盐类;在182d的养殖期间,对所有处理组和对照组池塘的17项水质和5项底质因子进行了定期监测.结果表明,各处理组均显著降低了池塘水中的蓝藻相对密度;KCl+MgCl2的施用可促进水中硝化作用的进行;NaNO3+KCl+MgCl2的施用,显著提高了养殖池塘底泥表层的氧化还原电位;NaNO3+KCl+MgCl2组的池塘鱼产量比对照组显著提高6.6%,而饲料系数显著降低6.2%;NaNO3与KCl+MgCl2的共同施用起到了协同改良池塘水质和底质的作用.因此,NaNO3+KCl+MgCl2的应用可为淡水池塘水质的改良开辟一个新的途径,具有一定的应用前景.     

Intensive culture of grass carp, Ctenopharyngodon idella, in circular tanks

Fingerling grass carp ( Ctenopharyngodon idella ) were cultured in 380 1 circular fiberglass tanks at stocking densities of 0.53, 1.06, 1.59 and 2.11 fish/1. Fish were fed duckweed ( Lemna minima ) to satiation. Fish grew from 2.7 g to a maximum mean weight of 72.7 g in 88 days. Fish stocked at 0.53 fish/1 grow more rapidly than those stocked at higher densities. Mean daily consumption rates were strongly correlated with oxygen levels and when oxygen levels dropped below 4 mg/1 consumption was reduced approximately 40%. High biomass, growth, and survival rates obtained during this study indicate grass carp are well suited for intensive tank culture.     

轮虫培育池生态系统颗粒悬浮物的研究

对两种模式轮虫培育池的悬浮物结构及动态进行了比较研究．结果表明,颗粒悬浮物总量波动在6．76～65．39mg·L^-1之间．静水池塘14#颗粒悬浮物平均值为11．50mg·L^-1,其中颗粒有机物占66．8％,浮游植物占30．5％,浮游动物占5．3％。颗粒腐质和细菌占31％,颗粒无机物占33．2％．流水池塘82#池颗粒悬浮物平均值为41．83mg·L^-1,其中颗粒有机物占70．4％,浮游植物占30％,浮游动物占1．2％,颗粒腐质和细菌占39．2％,颗粒无机物占29．6％．颗粒悬浮物含量静水轮虫池小于流水轮虫池．轮虫培育池是一类特殊类型的生态系统,消费者以褶皱臂尾轮虫为主,群落结构简单,生境易变,这些都会影响水层颗粒悬浮物的动态,造成其含量的较大波动和构成的改变．轮虫培育池生态系统颗粒悬浮物中以颗粒有机物所占比例较大,颗粒腐质和细菌所占份额与浮游生物量相当．     

The loss of submerged plants with eutrophication I. Experimental design, water chemistry, aquatic plant and phytoplankton biomass in experiments carried out in ponds in the Norfolk Broadland

SUMMARY. 1 During eutrophication of shallow lakes, communities of submerged plants are often replaced by dense phytoplankton populations, but the mechanism by which this occurs is obscure though often assumed to involve shading. 2. This paper introduces a series investigating this change and describes a system of experimental ponds which were variously fertilized with nitrogen and phosphorus, had fish added or removed, and had their submerged aquatic plants cleared or left intact. 3. Fertilization with phosphate and ammonium nitrate in quantities effectively greater than those in a series of lakes in the adjacent Norfolk Broads, which have lost their submerged plants, did not displace the plant populations. 4. Total phosphorus and soluble reactive phosphorus concentrations in the water did not increase much with increasing loading in the presence of submerged plants but did so if the plants were manually cleared. Ammonium and nitrate concentrations were kept low, despite large additions in both plant dominated and manually cleared ponds. 5. In the absence of fish there were modest increases in chlorophyll a concentrations with phosphorus loading in the presence or absence of submerged plants. The concentrations achieved, however, were much lower than anticipated probably because of grazing by large-bodied Cladocera. 6. Ponds dominated by plants continued to have low phytoplankton populations even when fish were stocked. Low fish survival in these ponds permitted grazing zooplankters to flourish. In ponds cleared of plants, however, there were significant relationships between cholorophyll a concentration with Daphnia biomass (inverse) and log stock of potentially zooplanktivorous fish (positive). There was a significant relationship between chlorophyll a and total phosphorus concentrations in the plant and cleared ponds in 1982 but only in the plant ponds in 1983. In all cases the phytoplankton communities were dominated by small, often flagellated, organisms.