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1.
将“天辰水产专用液体肥”定量施放在池塘养殖水体中后,定时检测水体中浮游生物量和种群结构的变化。结果表明,对照池Ⅰ、Ⅲ和Ⅴ号浮游植物的量为0.1mg/L￣0.2mg/L,浮游动物的量为0.1mg/L￣0.2mg/L;而试验池塘中经过2次施放肥料后,浮游植物的量上升为0.1mg/L￣0.3mg/L,浮游动物的量为0.2mg/L￣0.3mg/L。浮游植物中蓝藻和绿藻数量虽然在施肥后数量有所上升,但没有硅藻明显。3个试验池塘中浮游动物的数量也有明显的上升。 相似文献
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试验表明:施用微生物菌肥能稳定pH值,显著降解水体氨氮、亚硝酸盐、化学需氧量(COD)的含量,促进浮游生物生长,增加浮游生物量,浮游植物和浮游动物试验池比对照池分别提高67.50%(p<0.01)和165.98% (p<0.01)。出池鱼苗体重增加31.84%,体长增加31.49%,成活率提高22.77%。 相似文献
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选择辽宁盘锦光合水产有限公司养殖基地为试验场所,于2002年春季4~5月进行试验。选择5个具有代表性的土池作为试验池,同时另选一土池作为对照池。研究相同N/P比值下不同施肥量对室外土池多盐水体的水化学和浮游植物群落、叶绿素a含量和初级生产力的影响,以及浮游动物对浮游植物的下行效应。共检出浮游生物42种。其中,浮游植物33种,浮游动物9种。浮游植物生物量高达288.2 mg.L-1,优势种为蛋白核小球藻(Chlorella pyrenoidesa)。叶绿素a含量为5.89~325.44μg.L-1。各池在第2次施肥后5~6天,叶绿素a含量达到高值,之后开始下降,8~9 d后恢复到原来水平。初级生产力均值为4.40 g(O2).m-2.d-1,呈低-高-低的变化,极值为1.25 g(O2).m-2.d-1和10.92 g(O2).m-2.d-1。以施N 2.0 mg.L-1、P 0.3 mg.L-1的4#池高峰期维持最长,施肥量的不同对浮游植物的生物量、种类数和种类组成影响较大。在北方地区的多盐水池塘,施氮磷混合肥能有效促进小球藻等藻类增长,达到定向培育的目的。 相似文献
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有益微生物对海水养虾池浮游生物生态特征的影响研究 总被引：9，自引：6，他引：9
研究了有益微生物对海水虾池浮游生物生态特征的影响。通过对虾养殖系统中浮游动物与浮游植物进行为期3个月的监测,结果表明试验组虾池的浮游植物密度表现为前期低,中期迅速增长,后期达顶峰,并维持在70×106～160×106cell·L-1的水平,前期种类以硅藻类为主,后期则以绿藻类为主;同时试验池浮游动物的密度也保持稳定增长态势,并在养殖后期维持在顶峰水平,密度达到25×103～30×103ind·m-3,种类以广盐、适低盐的沿岸种为主,但优势种明显;对照池的浮游植物和浮游动物呈现前期低后期高的态势。其变化差异表现为对照组的浮游植物和浮游动物在后期的密度变动起伏较大,且出现较大比例的有害的兰藻类,而试验池的兰藻类只占较少的比例,说明芽孢杆菌群能抑制兰藻类的繁殖,促进有益藻类生长;浮游生物的多样性指数较低,低于自然海区,但种类均匀度则较高,与自然海区相当。 相似文献
5.
看水越冬及其生物学分析 总被引：1，自引：0，他引：1
根据黑龙江、吉林地区数十个鱼类越冬池的实测数据 ,从水色、透明度、浮游生物与水体溶氧间的相互关系 ,总结如下规律 :1 水体透明度与浮游植物量负相关 ,与浮游动物量正相关。透明度 <5 0cm者 ,浮游植物丰富而极少浮游动物 ,一般氧气充足 ;透明度 >80cm者 ,多滤食性浮游动物 ,浮游植物少 ,一般溶氧量较低。越冬池透明度以 5 0～ 70cm为宜。 2 根据水体透明度可了解越冬池营养盐的丰欠 ,在越冬中、后期“肥水 (浮游植物多 )易缺肥而瘦水 (浮游动物多 )不易缺肥”。 3 目测冰下水体中鱼类的活动状况和兼测水温变化 ,可为池鱼越冬效果预测提供重要依据 相似文献
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Supplemental Feeding of Tilapia in Fertilized Ponds 总被引：1，自引：0，他引：1
James S. Diana C. Kwei Lin Kitjar Jaiyen 《Journal of the World Aquaculture Society》1994,25(4):497-506
The addition of feed to fertilized fish ponds was evaluated by adding feed alone, feed plus fertilizer, or fertilizer alone to nine ponds stocked with Nile tilapia Oreochromis niloticus . Two experiments were conducted. The first had 500 fish per 250 m2 pond in 3 treatments: ad-libitum feeding; fertilizer only; or fertilizer and ad-libitum feeding. The second experiment had 5 treatments with 750 fish per pond ad-libitum feed only; fertilizer only; or 0.25, 0.50, and 0.75 satiation ration plus fertilizer. Ponds in Thailand were maintained for 155–162 d, during which chemical and physical properties were monitored. In experiment 1 tilapia growth was highest in feed only ponds, and lowest in fertilizer only ponds. Net yield did not differ significantly among treatments, due to variation in survival. In experiment 2, tilapia growth was lowest in fertilizer only ponds, intermediate in 0.25 ration ponds, and highest in 0.50, 0.75, and ad-libitum ponds. The latter treatments were not significantly different. Multiple regressions for each experiment indicated only 47–87% of the variance in growth was explained by feed and fertilizer input, while 52–89% of the variance in yield was explained by those factors. For both experiments combined, 90.3% of the variance in growth was explained by feed input, fertilizer input, alkalinity, and total inorganic nitrogen concentration. For yield, R 2 was 0.888 and the regression included feed input, pH, and number of low dissolved oxygen events. Experiment 1 appeared to approach carrying capacity near the end, while no reduction in growth occurred in experiment 2 at higher fish density and biomass. Reductions in growth in experiment 1 were not correlated with declining water quality late in the grow out. Combinations of feed and fertilizer were most efficient in growing tilapia to large size (500 g) compared to complete feeding or fertilizing alone. 相似文献
12.
Disinfection, Microbial Community Establishment and Shrimp Production in a Prototype Biosecure Pond 总被引：1，自引：0，他引：1
Delma Bratvold Jingrang Lu Craig L. Browdy 《Journal of the World Aquaculture Society》1999,30(4):422-432
Plankton community establishment and shrimp production in a prototype biosecure pond were compared to three control ponds. The biosecure pond was enclosed and intake water was disinfected, while control ponds were neither enclosed nor disinfected. All ponds were managed with no water exchange and stocked with 100 postlarvae/m2 , Litopenaeus vannamei . Residual oxidant concentrations in the biosecure pond dropped rapidly after cessation of chlorinated water addition. This was followed by a sharp increase in water column bacterial abundance, after which the pond was fertilized and inoculated with cultured Chaetocerous gracilis . After crash of the initial C. gracilis bloom in the biosecure pond, this species was not observed again. Following initial large fluctuations in biosecure pond bacterial abundance, phytoplankton biomass, oxygen consumption and nitrification rates, these parameters appeared to stabilize at levels similar to the control ponds. Early season compositional differences in phytoplankton, zooplankton, and bacterial communities were observed. No differences were seen in late-season phytoplankton and bacteria; however, zooplankton biomass tended to be lower in the biosecure pond than in the control ponds throughout the season. Shrimp production in all ponds was greater than 9,000 kg/ha. Production in the single biosecure pond was not a significant outlier compared to production in the triplicate control ponds. 相似文献
13.
《Journal Of Applied Aquaculture》2013,25(1-2):23-41
ABSTRACT Production of fingerlings from very small fry depends upon an initial high concentration of rotifers followed by high densities of crustacean zooplankton. High fertilization rates lead to increased zooplankton production but often cause poor water quality conditions that aeration may alleviate. This study was designed to determine the effects of constant, nocturnal, and no aeration on water quality, primary productivity, and standing crops of phytoplankton and zooplankton in heavily fertilized nursery-size ponds that contained no fish. Four 0.04-ha ponds were aerated continually; four ponds were aerated only at night with a 372-W (1/2 hp) paddlewheel aerator; and four ponds were not aerated. For 21 days after they were filled on July 21, 1999, the ponds received 1,224 kg/ha rice bran and 581kg/ha liquid 9-27-0 fertilizer. Water quality variables, primary production, chlorophyll-a and zooplankton were sampled daily. Constant aeration resulted in several conditions more conducive to survival of fish fry, such as higher zooplankton densities, more moderate temperatures, and safer dissolved oxygen levels than did nocturnal aeration or no aeration. However, the development of a higher standing crop of phytoplankton and higher total ammonia concentrations in the turbulent, constantly aerated ponds resulted in higher un-ionized ammonia levels that were not favorable to survival and growth of fry. The high concentrations of zooplankton that developed in the aerated ponds have good potential for cropping to inoculate other ponds or to provide live foods for tank culture of zooplanktivorous fish. 相似文献
14.
Pond experiments with one treatment per pond are discussed for their sources of variability. Replication of treated ponds, randomization of treatment allocation to ponds and the importance of independence between ponds are emphasized for efficient estimation of both treatment and inherent pond differences. Appropriate models are given for the analysis of data for pond experiments with whole-pond treatments. Corresponding analyses of variance are given to illustrate the estimation of differences between treatments, between ponds and between fish within ponds. Appropriate significance tests for treatment effects are demonstrated to avoid pseudoreplication, the incorrect use of within-pond variation. Using a fertilizer experiment, simple graphical methods are presented for examining between- and within-pond variation to identify ponds with unusual data, and to determine adequacy of design and appropriate analyses. 相似文献
15.
Abstract. Interactions between fish species and their effect on the ecological conditions in the fish pond were studied in ten ponds of 0.1 ha each. The ponds were stocked with bottom-feeding fish: common carp, Cyprinus carpio L., and male hybrid tilapia Oreochromis niioticus (L.) x O. aureus (Steindachner). and a filter-feeder: silver carp, Hypophthalmichtys molitrix (Valenciennes), in various combinations. This paper deals with the effect of different assemblages of these fishes on the phytoplankton populations in the ponds. A Principal Component Analysis of the data showed that only 20% of the phytoplanktonic variability is accounted for by the fish combination present in the pond (treatment). The first principal component (PCI) groups the species of phytoplankton which responded to treatment. This component is formed by small size species; Scenedesmus spp., small Chlorophytes (mainly Chlorella), Selenastrum minutum, Ankistrodesmus setigerus, Merismopedia minima and Diatoms of the order Pennales. The presence of silver carp led to an increase in total phytoplankton numbers, concurrently with a decrease in their dominant size. This was due to the predominance in the water of the small size species of the PCI group, which could not be retained by the gill filtering apparatus of the fish. Reduction in zooplankton abundance by silver carp also contributed to this situation. The presence of bottom-feeding fish resulted in a decrease in total phytoplankton numbers, and in the importance of the small-size species of the PCI group, and hence in the dominance of larger algae. The interactions between these two trophic types of fish and algae size are discussed. 相似文献
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《Journal Of Applied Aquaculture》2013,25(4):29-50
Four 2-m3 cages each stocked with 120 bighead carp ♀ X silver carp ♂ hybrids were placed in each of four ponds varying in trophic status from mesotrophic to hypereutrophic. Fish were cultured, without feeding, from 13 March to 1 October, 1987. All fish survived but lost weight (-0.37 g/fish/day) in the mesotrophic pond. Maximum fish growth rate occured in the two eutrophic ponds (6.61 and 7.04 g/fish/day). Fish growth in the hypereutrophic pond was about one-half (3.64 g/fish/day) that in the two eutrophic ponds until a sudden thermal destratification and dissolved oxygen depletion killed all the fish. Multiple linear regression analysis revealed that gross phytoplankton primary productivity accounted for 68% of the variation in fish weight gain (R2 = 0.68; P < 0.0001) in all ponds. When eliminating primary productivity data from the statistical model, number of algal taxa comprising phytoplankton communities explained 49% of the variation in fish growth (R2 = 0.49; P < 0.0001). Conditions of hypereutrophy believed to be detrimental to fish growth were: a decline in cladoceran density; a preponderance of blue-green algae, especially colonial forms with mucilaginous sheaths; a shift from numerous, relatively small plankton algal taxa to fewer but larger forms; degraded water quality. 相似文献
17.
Laban C. Lindley 《Journal Of Applied Aquaculture》2013,25(2):96-109
Copepod nauplii are a nutritious food item for first-feeding marine fish larvae. Unfortunately, mass culture techniques for producing copepod nauplii are not well established. Copepod nauplii can be collected from wild zooplankton populations or specially prepared ponds and transferred to larval fish tanks for feeding. This study evaluated the use of two trapping methods for harvesting zooplankton, particularly copepod nauplii, from fertilized ponds and the impact on the zooplankton population. Nine, 0.11 ha brackish-water (～2-7 ppt salinity) ponds were filled and fertilized with organic and inorganic fertilizers. The change in zooplankton abundance, mainly rotifers, nauplii and adult copepods, was monitored in the ponds for 22 d following initial pond filling. Beginning on day 8, three ponds were trapped with a large plankton net (Trap I), three with a pump and bag trap method (Trap II), and three ponds were not trapped. The ponds were trapped with the corresponding method for 1 h per day, for 15 d. The two trapping methods were similar in their efficiency to harvest nauplii, averaging 8,383,400 ± 2,508,378/h and 6,695,822 ± 433,533/h for Traps I and II, respectively. The zooplankton harvested by Trap I was not correlated to the densities in the ponds. However, the number of rotifers and nauplii harvested by Trap II was correlated to the rotifer and nauplii densities in the ponds. Both trapping methods were similar in terms of labor requirements and ease of use. Both methods were effective in collecting zooplankton without negatively impacting pond abundance. 相似文献
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《Journal Of Applied Aquaculture》2013,25(1):45-55
Four 20m3 cages stocked with 120 bighead carp x silver carp hybrids per cage were placed in each of four ponds varying in trophic status from mesotrophic to hypereutophic. Fish were cultured, without feeding, from 13 March to 1 Octorber 1987. Fish in the mesotrophic pond survived but lost weight (-0.37 g/fish/d). The mesotrophic pond produced insufficient food to sustain fish growth. Maximum fish growth rate occured in the two eutotrophic ponds (6.61vand 7/04 g/fish/d). Fish growth in the hypereutrophic pond was about one-half (3.64 g/fish/d) that in the two eutrophic ponds. Guy analysis of fish in the hypereutrophic pond revealed consumption of larger quantities (P < 0.05) of colonial blue-green algae that were apparently poorly digested and less (P < 0.05) zooplankton (primarily cladocerans) than was found in fish from the eutrophic ponds. 相似文献
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《Journal Of Applied Aquaculture》2013,25(3-4):17-44
Abstract One of the most important issues concerning fish-pond fertilization is the determination of the optimal amount of fertilizer to be applied to the pond system. Another important concern is the suitability of fish species for polyculture in order to optimize production. The dynamics of nutrients, phytoplankton, and fish is a complex subject and practitioners are often compelled to formulate solutions without detailed scientific and practical consideration. The primary objective of pond fertilization is to maintain an optimal nutrient concentration for sustained biological production. Current fertilization practices in the Asia-Pacific region include: a fixed rate of fertilization and fertilization based on water color. Individual pond ecology determines how fertilization affects pond productivity, not the pond's physical location in relation to international borders. There is no universal recipe of “maximal” fertilization rates due to pond-specific variability. There is also no clear guide in the literature with regard to many aspects of fish-food; the type of organisms consumed, mechanisms of food consumption, and the digestibility and nutritive value of plankton. The usual practice is to divide fish according to their foraging in natural habitats; feeding on phytoplankton, zooplankton, zoo benthos, or detritus. The distinction between different feeding habits is not always absolute as many species of fish may change food preference depending on the abundance of different food items. This paper reviews the nutrient (nitrogen, N and phosphorus, P) management in regard to pond fertilization; use of organic and inorganic fertilizer and the impacts on fish production; use of organic fertilizer from different organisms (pig, cow and buffalo) and their interactions with primary production and water quality; optimum N:P concentration in pond water; and individual pond factors and their influence on fish production. A significant interaction was evident with time between water quality variables such as pH and alkalinity, and other factors, including manure type and fish species composition. This was reflected in the difference between pig and cow manure treatments. A significant interaction between species composition and fish production has been demonstrated. Fish survival and biomass production was influenced by the stocking ratio of the: rohu, Labeo rohita; mrigal, Cirrhinus mrigala; and Nile tilapia, Oreochromis niloticus. The recommended nutrient level for pond fertilization based on the South Australian Research and Development Institute (SARDI) and Research Institute for Aquaculture No. 1 (RIA#1) study is 1 ppm N:0.5 ppm P. The required quantity of fertilizer varies significantly with time. However, regional research is highly recommended to optimize fish production focusing on significant climate variability, which affects both primary and secondary production. 相似文献