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Relationships between phytoplankton periodicity and the concentrations of total and unionized ammonia in channel catfish ponds

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Abstract

Phytoplankton abundance fluctuated throughout a 9 month study period in two 1.62 ha channel catfish (Ictalurus punctatus) production ponds. Summer phytoplankton communities in both ponds were dominated by blue-green algae (Cyanophyta). During periods of rapidly decreasing phytoplankton abundance, total ammonia-nitrogen concentrations increased but a decrease in pH during these same periods moderated the concentrations of unionized ammonia-nitrogen. Although unionized ammonia-nitrogen concentrations did not reach levels considered acutely toxic to fish, extended periods of moderately high unionized ammonia-nitrogen concentrations (>O.15 mg/1) occurred in the late fall months and may have serious implications for fish health.

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... Ponds having algal densities greater than 1000 Anabaena filaments per ml (approximately 50 µgL -1 chlorophyll "a") showed 81% phytoplankton die-offs each spring. Die-offs often produce high levels of ammonia which can discourage fish feeding and growth for periods of 10-15 days (Tucker et al., 1984). Since total fish production depends on the length of the growing season, each severe algal die-off can reduce fish production in a 180-day growing season by 6-8%. ...
... The increase in chlorophyll "a" content with time in fish pond (Table, 2 and Fig, 2) was due to the accumulation of incomplete cropping of the algae by fish where the blue-green algae which ranged between 60 to 90% in all treatments. The decomposition of this heavy load of algae and the release of ammonia as a by-product (Tucker et al., 1984). Zooplankton consume phytoplankton, but they consume primarily small phytoplankton less than 25 µm in diameter (Gliwicz, 1969(Gliwicz, , 1977McCauley and Downing, 1985) and are apparently unable to control algal biomass in fish ponds (Vyhnalek, 1983). ...
... This is because human moved to urban areas to get a better job, better healthcare, and better educational opportunities. Tarazona et al. (1987) found high ammonia concentration caused a toxic effect on biotic variables, Tucker et al. (1984) found that high ammonia concentration was found in the polluted water near an urban area. Olowe and Kumarasamy (2017) found that organic waste discharge caused high ammonia concentration in aquatic bodies. ...
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Surma River of Bangladesh is a representative of sub-tropical river system which is complex, dynamic and interacting socio-ecological system. Though land-based activities control the water quality of this river system, no studies have been conducted on the role of land-use patterns on water quality and biotic communities. Therefore, this study aimed to understand the impacts of water quality on the plankton community dynamics of Surma River basin. In addition, the study also examined the impacts of land-use patterns on water quality of river. Land-use patterns were identified by analyzing Landsat-8 imageries of the United State Geological Survey. Data on biotic and abiotic variables were collected from 15 sampling stations during dry season. Unsupervised and supervised classification techniques were used to identify the land-use patterns. Weighted arithmetic method was used to develop water quality index of river system. This study found four types of land-use patterns around Surma River basin (i.e., built-up area, barren land, river, vegetation and agriculture). Water quality index indicates that water quality is good in the rural area, while bad in the urban areas. Our study found that land-use pattern is a good predictor of water quality (R² = 0.97) of Surma River basin. Our study also found that high plankton species diversity coincides with the good water quality of the river. This study will serve as tool for the management of Surma River basin of Bangladesh.
... Decomposition of the dead plants can also result in elevated total ammonia concentrations in the ponds (Tucker et al. 1983, Boyd and. Further, elimination of phytoplankton via algaecidal use will also decrease the rate at which ammonia is removed from the pond water, and result in the production of nitrite via nitrification of ammonia (Tucker et al. 1984a). Elevated levels of both ammonia (specifically unionized ammonia) and nitrite can be toxic to fishes . ...
... During phytoplankton busts, both ammonia and Carbondioxide are liberated into the water column. Because freshwater has low buffering effect, Carbondioxide can accumulate in the water, thus lowering the pH in ponds considerably and reducing the amount of un-ionized ammonia (Tucker et al., 1984). Marine fishponds have large carbonate alkalinity which buffers its effect resulting in relatively higher levels of un-ionized ammonia, which is toxic (Krom et al., 1985). ...
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The aim of this study was to describe the differences in Length-Weight relationship and condition factor of Tilapia zillii and Oreochromis urolepis urolepis reared in full strength sea water (FSSW) and fresh water (FW) ponds. The environmental condition in FSSW and FW ponds were also analyzed to determine their impacts on Length-Weight relationship and condition factor on both species. The regression coefficient "b" exhibit negative allometric growth in FW and positive allometric growth in FSSW for both species. The value of exponent "b" and condition factor (K) for T. zillii in FW and FSSW (in the bracket) were found to be 2.94 (3.3) and 2.07 (0.74) respectively. On the other hand the value of exponent "b" and condition factor (K) for O. urolepis urolepis in FW and FSSW (in the bracket) were found to be 2.81 (3.46) and 0.86 (0.53) respectively. Though both species performed well in FW, the study also revelead that farming of these tilapia species in FSSW can be feasible if water quality parameters are properly monitored.
... During blooms and collapses, both ammonia and CO 2 are liberated into the water column. In freshwater with low buffering effect, CO 2 lowers the pH considerably, thus reducing the amount of un-ionised ammonia (Tucker et al., 1984). In marine fishponds, although a similar quantity of CO 2 may be produced, the large carbonate alkalinity buffers its effects, resulting in relatively higher levels of un-ionised ammonia (NH 3 ), which is toxic (Krom et al., 1985b). ...
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Six mariculture ponds were flooded with seawater since 1996. During this time the ponds were stocked with finfish (milkfish and rabbitfish), which were fed on locally produced fish feed. Some water quality parameters such as temperature, salinity and oxygen saturation were measured twice a day for three years (1998 - 2000), while nutrient concentrations were measured weekly for one year. Both nutrient concentration and oxygen saturation levels have shown a trend indicating eutrophication. Oxygen concentration changed from an average of 7.16 mg/l in October 1998 to 2.2 mg/l in March 2000 with a negative linear regression of 0.69 during the morning hours. From August 1998 to April 1999 dissolved inorganic ammonia concentration increased by 9 μg-at N/l, from 8.91 to 18.02 with a positive linear regression of 0.79. During this period soluble reactive phosphorus increased by 3.55 μg-at P/l from 4.36 to 7.91 with a positive linear regression of 0.75. In this paper the rate of eutrophication and the limit at which the ponds have to be dried/limed before restocking are discussed.
... Bloom decay, agricultural runoff, and sediment leaching are possible sources of ammonia to Upper Klamath Lake (Wood et al. 1996). Un-ionized ammonia is toxic to fishes at relatively low concentrations (Tucker et al. 1984; Rasmussen and Korsgaard 1996; Saiki et al. 1999), and in 1997 un-ionized ammonia concentrations in Upper Klamath Lake reached levels toxic to suckers, as judged by median tolerance limits computed by Saiki et al. (1999). ...
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Poor water quality from hypereutrophic Upper Klamath Lake in south-central Oregon has been suspected of contributing to the recruitment failure of two endangered endemic fish species, the Lost River sucker Deltistes luxatus and the shortnose sucker Chasmistes brevirostris. We used otolith daily increment widths as a proxy for juvenile somatic growth to construct two growth models: (1) a linear mixed-effects (LME) model examining the lifetime effects of lakewide averages of potentially stressful daytime water temperature, pH, and nighttime dissolved oxygen (DO), and (2) a simple linear regression model examining the effects of locally measured water temperature, pH, and daytime DO on growth of fish over 3 d before the fish's capture. Graphical relationships between daily growth and biweekly un-ionized ammonia failed to show a sublethal effect on the growth of suckers captured in areas where un-ionized ammonia surpassed levels lethal to both species. For both species, our LME models indicated that at temperatures greater than approximately 22°C, low nighttime DO (less than 4 mg/L for Lost River suckers and less than 1 mg/L for shortnose suckers) caused enough stress to reduce growth, whereas at temperatures less than approximately 22°C, any stress from low nighttime DO was not reflected in reduced growth. We attribute the pattern to the species' tolerance of low DO, the short duration of nighttime events, the fish's increased oxygen demand at higher temperatures, and growth compensation due to increased food resources associated with low DO. The combination of low DO and high temperature has also been implicated in adult fish kills in Upper Klamath Lake. Because 34% of the time lakewide August average temperatures exceeded 22°C, extended periods of warm temperatures and high primary production could affect the sizes of recruits surviving into fall. Both growth models suggested that shortnose suckers might be more tolerant of poor water quality than Lost River suckers.
... The nitrogen demand of the larger June and July algal populations may have contributed to greater ammonia limitation during these months. Ammonia is generally the preferred nitrogen source for phytoplankton (Syrett, 1981) and has been found to be inversely related to algal density in aquaculture ponds (Tucker et al., 1984). Dissolved organic matter (DOM) from phytoplankton is thought to be a major source of nutrients for bacteria in eutrophic estuaries (Bjornsen et al., 1989;Coffin et al., 1993). ...
Article
Simple electrometric methods were tested to estimate microbial activity in hypereutrophic aquaculture ponds using equipment common at aquaculture facilities for biochemical oxygen demand (BOD) measurements. Activity measurements tested included net photosynthesis based on changes in dissolved oxygen (DO) concentrations in samples incubated under light and dark conditions; general microbial activity as indicated by oxygen consumption rates in the dark; nutrient limitations as indicated by changes in DO consumption rates with nutrient additions; and nitrification based on the difference in DO consumption rates between samples incubated with and without a nitrification inhibitor. Method evaluations in intensive shrimp culture ponds suggest that simple electrometric methods are a good index of water column microbial activity under a range of conditions.
... The inverse relationship between phytoplankton biomass and dissolved inorganic nitrogen in Year 2 is consistent with typical nitrogen dynamics in channel catfish ponds (Tucker et al. 1983;Tucker and van der Ploeg 1993;Hargreaves and Tucker 1996). As explained above, algal uptake is the primary warmweather sink for dissolved inorganic nitrogen (Hargreaves and Tucker 1996;Hargreaves 1997Hargreaves , 1998, and factors that increase or decrease phytoplankton growth rates have the opposite effect on dissolved inorganic nitrogen concentrations. ...
Article
Twelve, 0.1-ha earthen ponds at Stoneville, Mississippi were used in a 2-year, double-blind study of the effects of a Bacillus-based bacterial bioaugmentation product on water quality and production of channel catfish Ictalurus punctatus. Each year, six ponds were treated weekly with the microbial product from late May or early June through October, and six ponds were designated as untreated controls. Mean concentrations of chlorophyll a, nitrite-N, and total ammonia-N did not significantly differ (P > 0.05) between bacteria-treated and untreated ponds in the first year; however, in the second year, mean chlorophyll-a concentrations were higher (P ≤ 0.05) and nitrite-N and total ammonia-N concentrations were lower (P ≤ 0.05) in bacteria-treated ponds than in untreated ponds. Reductions in dissolved inorganic nitrogen concentrations were more likely due to increased phytoplankton growth (i.e., increased algal assimilation) than to a direct effect of bacterial inoculation. The mechanism by which bioaugmentation may have enhanced phytoplankton growth is unknown and contradicts several past studies. Net fish production and feed conversion ratios were not affected by bacterial treatment in either year (P > 0.05); accordingly, there is no economic incentive to use Bacillus-bacterial bioaugmentation products in channel catfish ponds.
... Fortunately, ammonia is generally low when phytoplankton populations are high with corresponding high pH values and percentages of unionized ammonia. The relationship between phytoplankton periodicity, pH, and concentrations of TAN and unionized ammonia in these shrimp ponds were very similar to that described for freshwater catfish ponds by Tucker et al. (1984). Ammonia concentrations were low initially but the magnitude of fluctuations and, thus, average concentration tended to increase as the season progressed. ...
Article
Water exchange is routinely used in shrimp culture. However, there are few, if any, systematic investigations upon which to base exchange rates. Furthermore, environmental impacts of pond effluent threaten to hinder further development of shrimp farming in the U.S. The present study was designed to determine effects of normal (25.0%/d), reduced (2.5%/d) and no (0%/d) water exchange on water quality and production in intensive shrimp ponds stocked with Penaeus setiferus at 44 postlarvae/m2. Additional no-exchange ponds were stocked with 22 and 66 postlarvae/m2 to explore density effects. Water exchange rates and stocking density influenced most water quality parameters measured, including dissolved oxygen, pH, ammonia, nitrite, nitrate, Kjeldahl nitrogen, soluble orthophosphate, biochemical oxygen demand, phytoplankton and salinity. Reduced-exchange and no-exchange treatments resulted in reduced potential for environmental impact. Mass balance of nitrogen for the system indicates that 13–46% of nitrogen input via feed is lost through nitrification and atmospheric diffusion. Growth and survival were excellent in ponds with normal exchange, reduced exchange, and a combination of low density with no water exchange. A combination of higher stocking density and no water exchange resulted in mass mortalities. Mortalities could not be attributed to a toxic effect of any one water quality parameter. Production was 6,400 kg/ha/crop with moderate stocking density (44/m2) and reduced (2.5%/d) water exchange and 3,200 kg/ha/crop with lower stocking density (22/m2) and no water exchange. Results indicate that typical water exchange rates used in intensive shrimp farms may be drastically reduced resulting in a cost savings to farms and reduced potential for environmental impact from effluent.
... In freshwater fishponds it has been shown that plankton blooms and crashes can cause mass mortalities of fish (Boyd, 1979;Shilo and Rimon, 1982). However, there are very few description of the water quality conditions in such ponds during a bloom and crash cycle (Abeliovitch, 1967;Boyd et al., 1975;Tucker et al., 1984). Mass mortalities of fish are important, amongst other reasons, because they limit the total biomass of fish in the seawater ponds in Eilat (Krom et al., 1985c ) . ...
Article
Chlorophyll and dissolved nutrients were measured daily in two adjacent marine fishponds during one summer and one winter month. The two ponds were supplied continuously with nutrient-rich water from a seawater well at a dilution rate of 0.38 day−1 and received daily inputs of fish food. The fishponds behave as hypertrophic systems with high primary productivity and phytoplankton biomass. They are unstable, with frequent plankton blooms and crashes. Three bloom and crash cycles of phytoplankton (diatoms) were recognised and described in detail. In general, the dissolved inorganic nutrients showed an inverse relationship to the chlorophyll-a concentration. The rate of regrowth of phytoplankton after a crash was temperature controlled, with a Q10 of 2.3 which is similar to that found in laboratory studies. The phytoplankton took up ammonia-N until it was depleted and only then took up nitrate. There was a rapid uptake of nutrients which occurred on a timescale of minutes. Nutrient uptake occurred throughout the day and night. It was suggested that the crashes could not be caused by simple nutrient limitation resulting from changes in nutrient supply, and are most likely due to flagellate grazing. The ponds had a higher phytoplankton biomass and growth rate after a crash in summer than in winter. Both the pond which had been exposed to the air for 42 days the previous summer (dried) and the aged (non-dried) pond had similar nutrient-phytoplankton interactions; however, the timing of blooms and the species composition were different. The level of ammonia reached during crashes was higher in the aged pond due to in situ organic matter decomposition. For such intermediate flow ponds with a high plankton biomass, there are two critical periods when acute water quality problems may occur. During blooms, extreme values of dissolved oxygen can occur, and during crashes, high ammonia and low oxygen occur. The results explain why the water quality problems in this type of pond are only acute and not chronic.
... Thus, ammonia is utilized first and the levels in the water column are normally low. Tucker et al. (1984), Hopkins et al. (1994) and Pusceddu et al. (2011) have observed an inverse relationship between ammonia concentration and phytoplankton density in fish ponds. Dense phytoplankton populations are often developed in semi-intensive ponds due to a high rate of nutrient input (Hargreaves 1998). ...
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Studies to determine suitable levels of intensification are essential for developing sustainable aquaculture. The objective of this study was to evaluate the quality of effluents discharged from ponds stocked with 10 (D10), 20 (D20), 40 (D40), and 80 (D80) postlarvae of Macrobrachium amazonicum/m2. Intake and effluent water samples were taken throughout a 5.5-mo grow-out cycle. In that study, twelve 0.01-ha earthen ponds were stocked postlarvae with 0.01 g. Average water exchange rate was 15%/d; water was discharged from the bottom of the ponds. Prawns were fed a commercial feed with 38% crude protein according to their biomass (3–10%) and the concentration of dissolved oxygen (DO). In our research, temperature, turbidity, total suspended solids, conductivity, DO, pH, biochemical oxygen demand (BOD), chemical oxygen demand (COD), N-ammonia, N-nitrite, N-nitrate, N-Kjeldahl nitrogen, total phosphorus, and soluble orthophosphate were measured every 15 d throughout the experiment in the early morning (0630 to 0730 h). Turbidity was lower in D10 than in D20 and D40 and total phosphorus was higher in D80 than in D10 and D20. An analysis of principal components comparing treatments and intake water showed three groups: intake, D10 and a cluster of D20, D40, and D80. On the basis of the water characteristics found in our study it appears that the farming of M. amazonicum is likely to have a low environmental impact, at least up to a stocking density of 80 prawns/m2.
... The high rate of mechanical aeration used in ponds splashed water into the air, a process that also favors ammonia loss by diffusion to the air. Ammonia nitrogen is rapidly absorbed by phytoplankton for use in protein synthesis (Tucker et al. 1984). Moreover, ammonia is oxidized to nitrate by nitrifying bacteria (Boyd and Tucker 1998). ...
Article
Common water quality variables in nine, inland low‐salinity shrimp ponds in Alabama exhibited wide variation in concentrations among ponds and over time. Shrimp performance also varied considerably among ponds in 2008 as follows: survival, 16–128%; production, 928–5950 kg/ha; feed conversion ratio (FCR), 1.18–2.89. Measured water quality variables were not at concentrations high enough to be lethal to shrimp; but water temperature, dissolved oxygen, carbon dioxide, total ammonia nitrogen, calcium, and magnesium were occasionally outside optimum ranges for shrimp production and may have stressed shrimp. Survival and production both were positively correlated (P P
... Bloom decay, agricultural runoff, and sediment leaching are possible sources of ammonia to Upper Klamath Lake (Wood et al. 1996). Un-ionized ammonia is toxic to fishes at relatively low concentrations (Tucker et al. 1984; Rasmussen and Korsgaard 1996; Saiki et al. 1999), and in 1997 un-ionized ammonia concentrations in Upper Klamath Lake reached levels toxic to suckers, as judged by median tolerance limits computed by Saiki et al. (1999). ...
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Seventy-four lapilli from Lost River suckers captured in Upper Klamath Lake in 1970 during a snag fishery on spawning adults and 192 lapilli from adults sacrificed from 2001–2006 were examined to determine age and growth parameters; lapilli from 165 shortnose suckers sacrificed from Upper Klamath Lake from 2001–2006 were also examined. Relative marginal distance analyses indicated that growth marks were annuli and formed in December–January. Lost River suckers from the historic collection were aged to 57years, while Lost River and shortnose suckers from the recent collection were aged to 40years and 24years, respectively. Larger and older Lost River suckers were represented in the historic collection compared to the recent collection. Uncoupling of otolith length and fish length in Lost River suckers as well as a large spread in the predicted age- at-size for shortnose suckers precluded the ability to back-calculate size-at-age. Likelihood ratio tests indicated the growth model parameters were significantly different at both the sex and collection level. Growth in body length for both species appeared determinate in that growth was rapid until maturity, and then slowed over several years until growth in length was nearly nonexistent; a 650–700mm Lost River sucker could be between 14 and 57years old, while a 460mm shortnose sucker could range from 12–24years old. In contrast, while growth in body length slowed for both species, body mass continued to increase. This growth strategy, which is also found in other western lake suckers, may allow for more energy to be utilized for reproduction and help populations persist in spite of years of limited recruitment or recruitment failure. KeywordsAge-Growth-Upper Klamath Lake-Lost River Sucker-Shortnose sucker
... First, it can lead to chronic oxygen deficits. Second, dense algal blooms collapse periodically leading to decomposition of the dead algae resulting in fish kills due to anoxia (Boyd et al. 1975;Barica 1975) as well as due to high levels of ammonia (Seymour 1980;Tucker et al. 1984). Third, blue-green algae exude chemicals-geosmin and methyl-isoborneol that taint fish flesh, i.e., causing offflavor of fish (Brown and Boyd 1982;Armstrong et al. 1986). ...
Article
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Cyanobacterial blooms commonly appear during the summer months in ponds, lakes and reservoirs in Bangladesh. In these areas, fish mortality, odorous water and fish and human skin irritation and eye inflammation have been reported. The influence of physicochemical factors on the occurrence of cyanobacteria and its toxin levels were evaluated in natural and drinking water in Bangladesh. A highly sensitive immunosorbent assay was used to detect microcystins (MCs). Cyanobacteria were found in 22 of 23 samples and the dominant species were Microcystis aeruginosa, followed by Microcystis flosaquae, Anabeana crassa and Aphanizomenon flosaquae. Cyanobacterial abundance varied from 39 to 1315 x 10(3) cells mL(-1) in natural water and 31 to 49 x 10(3) cells mL(-1) in tap water. MC concentrations were 25-82300 pg mL(-1) with the highest value measured in the fish research pond, followed by Isha kha Lake. In tap water, MC concentrations ranged from 30-32 pg mL(-1). The correlation between nitrate-nitrogen (NO3-N) concentration and cyanobacterial cell abundance was R2 = 0.62 while that between cyanobacterial abundance and MC concentration was R2 = 0.98. The increased NO3-N from fish feed, organic manure, poultry and dairy farm waste and fertilizer from agricultural land eutrophicated the water bodies and triggered cyanobacterial bloom formation. The increased amount of cyanobacteria produced MCs, subsequently reducing the water quality.
... First, it can lead to chronic oxygen deficits. Second, dense algal blooms collapse periodically leading to decomposition of the dead algae resulting in fish kills due to anoxia (Boyd et al. 1975;Barica 1975) as well as due to high levels of ammonia (Seymour 1980;Tucker et al. 1984). Third, blue-green algae exude chemicals-geosmin and methyl-isoborneol that taint fish flesh, i.e., causing offflavor of fish (Brown and Boyd 1982;Armstrong et al. 1986). ...
Article
Full-text available
Increased nutrients have led cyanobacteria to become dominant in many ponds, lakes and reservoirs in many countries of the world. The occurrence and abundance of cyanobacterial population were monitored in a lake (known as Isha Kha Lake) at Bangladesh Agricultural University campus, Mymensingh, Bangladesh. The hydrographic parameters such as water temperature, pH, chlorophyll-a and nutrients (NO3–N and PO4–P) were recorded to find out their relationship with the cyanobacterial bloom formation. During the study period five species of cyanobacteria namely, Microcystis aeruginosa Kütz., M. wesenbergii Kom., M. botrys Teli., M. viridis (A. Br.) Lemm. and Anabaena circinalis Rabenh., were identified and among them M. aeruginosa was the dominant species during the bloom period. At the peak period of bloom, the highest cell density of M. aeruginosa was 1550 × 103 cells ml−1 which comprised 97.45% among the blue-green algae and 96.84% to the total phytoplankton. The initiation and persistence of natural bloom of cyanobacteria, especially Microcystis spp. was found to be controlled by relatively high temperature (>25.00 °C) and nutrients, especially high NO3–N (3.80 mg l−1) concentration. Temperature and NO3–N showed positive correlation with cyanobacterial cells abundance which were r = 0.62 and r = 0.92. Therefore, it could be said that temperature and NO3–N made a favorable circumstance to form cyanobacterial bloom as in Isha Kha Lake. The Enzyme-linked Immunosorbent Assay revealed the concentration of MCs 37,460.00 pg ml−1 at the peak period of the bloom.
... concentrations do occur, they usually remain for a relatively brief period 5-10 days Ž . Tucker and Lloyd, 1984 . Consequently, ammonia would not be expected to cause as much growth reduction in fish cultured in ponds as that measured in this study. ...
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The effects of variable and fluctuating sublethal ammonia concentrations on plasma ammonia concentration, growth, feed conversion ratio and survival of juvenile hybrid striped bass Morone chrysops Y = M. saxatilis ?, channel catfish Ictalurus punctatus and blue tilapia Oreochromis aureus were evaluated in each of three sequential growth periods. Fish were cultured in a flow-through system in which pH was controlled to represent the diel pH variation known to occur Ž. in eutrophic aquaculture ponds. During the first growth period 29 days , pH was maintained at Ž. 8.0. During the second growth period 22-43 days , pH was controlled to fluctuate daily from Ž. 7.75 to 9.00, and during the third growth period 47-53 days , pH was controlled to fluctuate Ž. Ž daily from 7.50 to 9.50. Four nominal total ammonia-nitrogen TAN concentrations 0, 1, 2.5 and y1. 5 mg l were established as treatment groups. Plasma TAN concentrations of each species responded rapidly to changes in environmental NH-N concentration. Channel catfish most effectively excluded ammonia from blood. Plasma 3 TAN concentrations of blue tilapia were greater than those of hybrid striped bass and channel catfish. Of the three species evaluated, hybrid striped bass was the most sensitive to unionized y1 Ž y1 ammonia and died following brief daily exposure to 0.91 mg l NH-N 2.5 mg l TAN at pH 3. y1 9.00. Hybrid striped bass growth was affected by daily brief exposure to 0.65 mg l NH-N, 3 y1 Ž. but was not affected by brief daily exposure to 0.37 mg l NH-N P) 0.05. Brief daily 3 exposure to 0.91 mg l y1 NH-N did not affect channel catfish or blue tilapia growth and feed 3 conversion ratio. The results of this study, in combination with published reports of ammonia q This is publication number J-9725 of the Mississippi Agricultural and Forestry Experiment Station.) Corresponding author. Tel.: q1-662-325-0629. 0044-8486r01r$-see front matter q 2001 Elsevier Science B.V. All rights reserved. Ž. PII: S 0 0 4 4-8 4 8 6 0 0 0 0 5 4 3-3 () J.A. HargreaÕes, S. Kucuk r Aquaculture 195 2001 163-181 164 concentrations that are normally prevalent in eutrophic aquaculture ponds, suggest that sublethal ammonia exposure in such ponds has a minimal effect on fish growth. q
... Higher concentrations of TAN are often found in catfish ponds (Tucker et al., 1984). The highest concentration for the drained treatment occurred the first year, when the growing season average was significantly greater (P < 0.01) than for the undrained treatment (Table I). ...
Article
Concentrations of chlorophyll a, total phosphorus, chemical oxygen demand, nitrite-nitrogen, total ammonia-nitrogen, and dissolved oxygen were measured frequently in channel catfish ponds, of which four were drained annually and four were not drained for 3 years. Average concentrations of total phosphorus increased from year to year in undrained ponds, and they were higher (P < 0.01) in undrained ponds than in drained ponds during the second and third years of the study. Phytoplankton abundance, as evident from chlorophyll a concentrations, did not differ (P > 0.05) within or between treatments during the 3 years. Water quality was similar between treatments. One difference in production of channel catfish occurred during the third year and was related to a parasite infection of fish rather than water quality. The findings suggest that the recent trend in not draining channel catfish ponds at harvest will not lead to rapid deterioration of water quality in ponds.
... the total produced biomass of algae was estimated to be 1.16 mg l − 1 on day 56. The importance of phytoplankton as a regulator of ammonia concentrations in fish ponds is well known (Tucker et al., 1984;Krom et al., 1989), and uptake of dissolved inorganic nitrogen from the water column is the primary pathway of nitrogen removal (Barica, 1974;Boyd, 1974). The uptake rate of nitrogen by phytoplankton was 264.4 mg N m − 2 d − 1 at the beginning of the experiment, decreasing during the growing cycle, partly due to nutrient and light limitations, the last caused by algal self-shading. ...
Article
Nitrogen is a key element in aquatic environments and an important pond management variable. In aquaculture systems, nitrogen accumulation eventually leads to a deterioration of the system. The interactions between various N-species are complex and difficult to integrate. Modelling can improve our ability to evaluate this complex system. This paper integrates existing knowledge about nitrogen transformations in fish ponds into a model that calculates the amount of various N-compounds in the water column and in the sediment. The model is also used to gain insight into the relative importance of transformation processes between the various N-compounds. The model was divided into three modules: fish, phytoplankton and sediment-water. The fish module is based on physiological and bio-energetic principles. The phytoplankton dynamics module is based on physico-chemical principles of alga growth. The water–sediment module is based on the bacterial transformations and chemical fluxes of N-species across the water–sediment interface. Relationships and parameters were taken from the literature, except for a few parameters that were estimated by fitting model predictions to observed data. The model was implemented in Turbo Pascal (7.0) using a fixed time step of 1 h and it was calibrated using a set of data from an earthen fish pond stocked with Colossoma macropomum. The validation was performed using data from earthen ponds stocked with Oreochromis niloticus. The difference between the calibrated and validated model was related to the fish species. All concentrations of the various N-species present were simulated well, except the N retained in organic matter in the sediment (average relative error −0.34). Sensitivity analysis revealed that the concentrations of inorganic-N compounds, both in the water column and in the sediment, are more affected by changes in specific parameters included in the fish and phytoplankton modules than other forms of nitrogen in the pond. The model works well, except for organic matter accumulation in the sediment. Further research should concentrate on a better understanding of the bottom organic matter dynamics, to make the model a more comprehensive predictive tool.
... First, it can lead to chronic oxygen deficits. Second, dense algal blooms collapse periodically leading to decomposition of the dead algae resulting in fish kills due to anoxia (Boyd et al. 1975;Barica 1975) as well as due to high levels of ammonia (Seymour 1980;Tucker et al. 1984). Third, blue-green algae exude chemicals-geosmin and methyl-isoborneol that taint fish flesh, i.e., causing offflavor of fish (Brown and Boyd 1982;Armstrong et al. 1986). ...
... Boyd and Musig (1980) showed that the rate of decline in spikes of SRP made to pond waters increased with increasing phytoplankton abundance. Tucker et al. (1984) demonstrated that TAN concentrations in fish pond waters decreased as phytoplankton abundance increased. Thus, the apparent trend in lower nutrient concentrations and in higher BOD and COD values in control ponds is consistent with thc explanation that AC+ reduced the phytoplankton abundance. ...
Article
A bio-organic catalyst was tcstcd in ponds used to grow channel catfish, Ictalurus punctatus, at Auburn, Alabama, for its effect on water quality, soil organic carbon, and channel catfish production. Although there were no significant differences (P > 0. I), ponds treated with the bio-organic catalyst tended to have higher concentrations of dissolved oxygen than control ponds during summer months even though all ponds were aerated mechanically. Data on water aualitv and soil organic carbon suagested that the bio-organic cataiyst caused a slightbut statisticall$~significant inhibition of phytoplankton productivity, which in turn lessened the nighttime oxygen demand. klthough fish production did not increaseas the result of greater dissolved oxygen availability, fish survival was higher in the treated ponds (P = 0.1). At the maximum daily feeding rate of 75 kgiha, water quality was not severely impaired in any of the ponds. The bio-organic catalyst product might have grcater benefits in ponds with higher stocking and feeding rates. Information on the mechanism of action of bio-catalyst additions in pond ecosystems would be useful in determining their potential bencfits to pond aquaculture.
... This is undesirable because high pH stresses fish. Ponds to which feed is applied also may have elevated total ammonia nitrogen (TAN) concentration (Tucker et al. 1984;Zhou and Boyd 2014). At elevated pH, a high proportion of the ammonia nitrogen is in the toxic, ammonia (NH 3 ) form as opposed to the less toxic ammonium (NH 4 + ) form ...
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Catfish farmers should use high-quality water to fill ponds and then manage water quality within the tolerance limits to optimize growth, survival, and feed conversion. Finding good quality water to fill ponds is relatively easy, but maintaining environmental conditions within the tolerance limits of catfish is challenging. Historically, the technical development of catfish farming in static ponds has been characterized by increasing intensification. The emergence of yield limits as catfish production has intensified can be attributed in part to water quality degradation associated with eutrophication. Thus, the need for research on water quality dynamics and practical management of water quality problems is clear. Research on water quality in aquaculture ponds has provided tangible benefits to catfish producers. Specifically, research on pond aeration systems and the discovery that common salt can be used to manage nitrite toxicity have facilitated the intensification of catfish production.
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Tilapia yields and water quality were compared in 1000-m2 grow-out ponds that were unaerated, or aerated beginning at 10 or 30% of oxygen saturation. Tilapia yield and individual final size were significantly greater in aerated ponds than in unaerated ponds, but there were no significant differences between levels of aeration. Treatment means of organic-N, total P. chlorophyll a, net primary productivity, and total volatile solids were not significantly different. However, aeration caused higher clay turbidity as indicated by significantly higher total fixed solids and lower Secchi disk visibility in aerated treatments. Maintenance of oxygen above minimal levels augmented tilapia yields, but additional research is needed to make aerator use in tilapia culture more efficient and profitable.
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A mechanistic model was developed to simulate annual variation of ammonia concentration in commercial (levee-type) catfish ponds in the southeastern United States. A simple mass balance approach was used to describe ammonia concentration as the balance (residual) between nitrogen sources and sinks. Two primary source processes (fish excretion and sediment diffusion) and two primary sink processes (phytoplankton uptake and nitrification) were considered. Model output predicted that 25–33% of ammonia production was derived from sediment diffusion. The rate of phytoplankton uptake of N was expected to exceed nitrification during the growing season (April-October), whereas nitrification rate would exceed phytoplankton uptake during cooler months. Nitrification rate was bimodally distributed, with peaks in spring and fall, and was related to the interaction between ammonia concentration and water temperature. Sensitivity analysis of model parameters indicated that average annual ammonia concentration was most sensitive to the partition of nitrogenous excretion between solid and dissolved fractions, average feeding rate, and phytoplankton specific uptake rate. Average annual ammonia concentration was relatively insensitive to changes in feed conversion. Model output and results of the sensitivity analysis provide insight into the magnitude and relative importance of the processes affecting ammonia transformations in commercial catfish ponds and offer possibilities for the most effective management intervention.
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A data set describing annual variation of water quality in ten commercial channel catfish Ictalurus punctatus ponds was subjected to exploratory statistical analysis to infer ecological processes affecting pond water quality. Two factors explained 67% of the variation in concentrations of water quality variables. The first factor (Factor 1) explained 49% of the variance and was associated with a large negative loading by total ammonia-nitrogen and large positive loadings by total nitrogen, total phosphorus, chemical oxygen demand, and chlorophyll a. Factor 1 was interpreted with respect to factor loadings to represent the effect of phytoplankton biomass. The second factor (Factor 2) explained an additional 18% of the variance and was associated with a large negative loading by soluble reactive phosphorus and large positive loadings by nitrite-nitrogen and, to a lesser extent, nitrate-nitrogen. Factor 2 was interpreted to be related to variation in pond sediment oxygenation. Although factor analysis indicated the overwhelming effect of phytoplankton biomass on water quality, opportunities for management of phytoplankton communities in large commercial aquaculture ponds are limited. However, maintenance of an oxidized sediment-water interface may improve water quality by limiting the diffusion of reductant-soluble phosphorus from sediment to water and increasing sediment nitrification rates.
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If a fish pond is built on pesticide-free soil and filled with unpolluted fresh water, the initial water quality conditions are ideal for channel catfish culture. Dissolved oxygen concentrations are near saturation, and the water contains negligible concentrations of carbon dioxide, ammonia, nitrite, or other toxic substances. When fish are stocked and fed, the environment immediately begins to deteriorate and becomes less fit for the fish. The degree to which conditions deteriorate is related to the amount of fish waste reaching the water. This in turn is related to the number and weight of fish in the pond and the amount of feed they are offered.
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The paper deals with 45 species of 21 genera of fresh water blue green algae (BGA) from three different agro-climatic zones of Uttar Pradesh. Samples were collected from different habitats varying in physico-chemical properties. Out of 45 species, 13 species belonged to order Chroococcales, 31 to order Nostocales, while only 1 species belonged to order Stigonimatales i.e. Fischerella mucicola. The physico-chemical parameters like pH, temperature, dissolved oxygen, electrical conductivity, nitrate, nitrite and rainfall play an important role in the periodicity of BGA. A positive correlation was found between dissolved oxygen (DO) of different ponds and species diversity, except in the case of western region of Uttar Pradesh (Farukhabad and Mahoba districts) where a positive correlation was found in electrical conductivity and total dissolved solids.
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Channel catfish (Ictalurus punctatus) were stocked in 0.02 to 0.04-hectare ponds without aeration at three rates (4,942, 10,007, and 20,385 fish per hectare) and fed daily. Fish averaged 12 cm total length and 10 g at stocking. Each treatment was replicated six times. Maximum feeding rates of 34, 56, and 78 kg/hectare, respectively, were reached by midsummer. In the low treatment, no dissolved oxygen (DO) problems occurred, and survival was 99%. In the medium treatment, DO at dawn frequently fell below 2.0 mg/liter and some fish suffocated during an oxygen depletion in one pond; however, survival averaged 93%. In the high treatment, DO at dawn was usually below 2.0 mg/liter in August and September. Fish mortalities resulted from DO depletion in three ponds of the high treatment, but survival averaged 83%. Nitrite-nitrogen and un-ionized ammonia never reached concentrations recognized to be lethal to channel catfish in any of the treatments. However, concentrations of un-ionized ammonia were possibly high enough to have adversely affected growth. Even though the average weight of individual fish decreased, harvest weight of fish increased from low to high treatment. The low treatment produced an average of 2,990 kg/hectare of fish and a net economic gain of /1,136. The medium treatment produced an average 4,100 kg/hectare for a net gain of /1,303. The high treatment produced an average of 4,860 kg per hectare, but a net gain of only $671.
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The acute toxicity of ammonia in a hard, well-aerated water to bream, perch, roach, rudd, and rainbow trout was determined. While trout responded more quickly than the coarse fish so that they were more sensitive over a short period of exposure (1 day), their mortality rate subsequently dropped. The coarse fish, however, continued to die and extension of the test period to the time when the toxicity curves had become asymptotic with the time axis showed that all the species were equally sensitive. The importance of the slope of the concentration response curve in assessing concentrations permissible in the field is discussed.
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Channel catfish, Ictalurus punctatus, were injected intraperitoneally with a sublethal dose of Aerornonas hydrophila and then stressed for 144 h by being maintained either in a dissolved oxygen concentration of 1·5 mg/1, 1·2 mg/1 total ammonia, and/or 6·5 mg/1 free CO2 with a continuous inflow of water. A significant difference in percentage of mortality was noted between treatments (P < 0·05). The trunk kidneys of surviving stressed fish had significantly higher total bacterial counts than non-stressed controls. A. hydrophila was isolated from 67% of the stressed fish and 9% of the control fish. Edwardsiella tarda, apparently endemic in the population, was isolated from 43% of the stressed fish and 7% of the control fish. Histopathological lesions were in the gills, liver, spleen, trunk kidney, and head kidney of stressed fish, but not control fish.
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The acute toxicity of un-ionized ammonia, nitrite, and nitrate to 50–76-mm fingerling channel catfish (Ictalurus punctatus) was investigated using a static bioassay system at 22, 26 and 30°C. The 96-h LC50 values at 30°C for un-ionized ammonia, nitrite, and nitrate were 3.8, 44, and 6 200 mg/l.
Article
The growth of juvenile channel catfish (Ictalurus punctatus) was reduced in a linear manner during a 31 day growth trial when exposed to concentrations of ammcnia ranging from 48 to 989 μg/l NH3N (0.31 to 5.71 mg/l NH+4N). On a wet weight basis, growth was reduced by 50% at 517 μg/l NH3N and the no growth occured at 967 μg/l. The no growth level was 60% of 96-h LC50 value. Mortality was increased significantly at 989 μg/l NH3N and above. The sublethal effects of ammonia may depend, in part, on the concentrations of NH4+ and and Na+ in solution.
Anatomicohistopathological changes induced in carp (Cyprinus carpio) by ammonia water. Part 11. Effects of subtoxic concentrations
  • J Flis
Flis, J., 1963. Anatomicohistopathological changes induced in carp (Cyprinus carpio) by ammonia water. Part 11. Effects of subtoxic concentrations. Acta Hydrobiol. 10: 225 233.
Nutrition and feed-ing of channel catfish. Southern Cooperative Series
  • R R Stickney
  • R T Lovell
Stickney, R. R. & Lovell, R. T. (eds.), 1977. Nutrition and feed-ing of channel catfish. Southern Cooperative Series, Bull. 218.65 pp.
Influence of ammonia on aeromonad susceptibility in channel catfish
  • R M Flagg
  • L W Hinck
  • R. M. Flagg
Flagg, R. M. & Hinck, L. W., 1978. Influence of ammonia on aeromonad susceptibility in channel catfish. Proc. Ann. Conf. S.E. Fish and Wildl. Agencies. 32: 415-419.
Nutrition and feeding of channel catfish
  • R R Stickney
  • Lovell
Anatomicohistopathological changes induced in carp (Cyprinus carpio) by ammonia water. Part II. Effects of subtoxic concentrations
  • J Flis
  • J. Flis