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Shrimp Ponds (shrimp + pond)
Selected AbstractsAdsorption of Magnesium by Bottom Soils in Inland Brackish Water Shrimp Ponds in AlabamaJOURNAL OF THE WORLD AQUACULTURE SOCIETY, Issue 4 2010Harvey J. Pine Low-salinity (2.0,9.0 g/L) well waters used for inland culture of marine shrimp in Alabama are imbalanced with respect to ionic composition. Inputs of potassium (muriate of potash) and potassium-magnesium sulfate (Kmag®) fertilizers are used to correct these imbalances. Potassium is lost in overflow and intentional discharge, seepage, and through adsorption by bottom soils by exchangeable and non-exchangeable processes. This study was initiated to determine if bottom soils removed magnesium in the same manner as potassium. Laboratory soil,water mesocosms revealed that soils strongly adsorbed magnesium. The rate of adsorption tended to decline over time, indicating establishment of the equilibrium. Magnesium losses for the three soils ranged from 1405 to 1713 mg/tank (average = 1568 mg/tank). The cation exchange capacity (CEC) of the soils varied from 10.4 to 44.0 cmolc/kg (average = 24.6cmolc/kg). The decline in magnesium increased with higher soil CEC. In another trial, repeated exposures of soils to solutions of 40 mg Mg2+/L failed to saturate exchange sites, but rather maintained equilibrium with other base cations on soil adsorption sites. Dissolved sulfate resulting from additions of magnesium with magnesium sulfate heptahydrate (MgSO4·7H2O) was also monitored. Although difficulties of analysis occurred, sulfate was not adsorbed appreciably by the soils. [source] Relative Abundance and Species Composition of Gram-Negative, Aerobic Bacteria Associated with the Gut of Juvenile White Shrimp Litopenaeus vannamei Reared in Oligotrophic Well Water and Eutrophic Pond WaterJOURNAL OF THE WORLD AQUACULTURE SOCIETY, Issue 2 2000Shaun M. Moss Gut bacteria may contribute significantly to the growth and survival of cultured shrimp, although little is known about factors that affect bacterial community structure in shrimp guts. The objective of this study was to determine the abundance and species composition of gut bacteria in juvenile white shrimp Litopenaeus vannamei reared in two different environments. Eight 120-L tanks were stocked at a density of 8 shrimphank. Two treatments were tested for 10 d and consisted of tanks receiving flow-through water from one of two sources: 1) well water pumped from a sea-water aquifer (Well treatment), and 2) pond water pumped from an intensive shrimp pond (Pond treatment). Shrimp mid- and hindguts were excised on days 1, 3, 6, and 10 for enumeration of gram-negative, aerobic bacteria by quantifying colony-forming units (CFU) using standard microbiological plating techniques. Identification of bacterial isolates was made using the Biologa® GN Microplate system. Bacterial numbers were significantly greater (P > 0.05) in Well shrimp than in Pond shrimp on days 1 and 3. Following day 3, a decrease in bacterial numbers occurred in the Well shrimp, and no significant differences between treatments were observed on days 6 or 10. Guts from Well shrimp were dominated by Vibrio and Aero-monas, and these two genera accounted for 80,851 of the bacteria on each sampling day. Guts from Pond shrimp exhibited a greater bacterial diversity and were dominated by Vibrio, Aeromonas, and Pseudomonas. Flavobacterium were identified in the guts of Pond shrimp on days 3 and 10, but were not identified in any of the Well shrimp. A greater understanding of gut bacteria-shrimp interactions could lead to increased production and profitability for shrimp farmers through the development of more cost-effective feeds and novel disease control strategies. [source] Nutritional values of Apocyclops dengizicus (Copepoda: Cyclopoida) fed Chaetocerous calcitrans and Tetraselmis tetratheleAQUACULTURE RESEARCH, Issue 1 2008Omidvar Farhadian Abstract The cyclopoid copepod Apocyclops dengizicus was isolated from a marine shrimp pond, Penaeus monodon, Kuala Selangor, Malaysia, and reared in the laboratory for 3 months to establish a pure population stock. Amino acids and fatty acids of A. dengizicus were determined when fed Chaetocerous calcitrans (C), Tetraselmis tetrathele (T) and their combination (CT) (1:1 by number). The protein contents in A. dengizicus that received C, T and CT were 46.8%, 60.5% and 55.3% of dry weight respectively. Correspondingly, the lipid was 19.0%, 17.8% and 19.1% of dry weight for C, T and CT respectively. The A. dengizicus cultured on C, T and CT had total essential amino acids without tryptophan measurement of 57.1, 60.3 and 67.8 and total non-essential amino acids of 42.9%, 40.0% and 32.2% of total amino acids. The fatty acid content of A. dengizicus showed that it was able to synthesize docosahexenoic acid (22:6n-3, DHA), eicosapentaenoic acid (20:5n-3, EPA) and arachidonic acid (20: 4n-6, ARA) from examined microalgal diets. The DHA:EPA:ARA ratios of A. dengizicus fed on C, T and CT were 6.8:3.0:1, 14.0:5.8:1 and 11.6:2.6:1 respectively. Apocyclops dengizicus could be suitable live food for larval fish and shrimp rearing because it meets their nutritive requirements. [source] ECOSYSTEM MODELING: A TOOL TO UNDERSTAND THE INTERACTIONS BETWEEN EXTRACTIVE AND FED AQUACULTUREJOURNAL OF PHYCOLOGY, Issue 2001Article first published online: 24 SEP 200 Yarish, C. 1, Rawson, Jr. M. V.2, Chopin, T.3, Wang, D. R.4, Chen, C.4, Carmona, R.1, Chen, C.5 , Wang, L.4, Ji , R.5 and Sullivan, J.5 1University of Connecticut, Stamford, Connecticut 06901-2315, USA; 2Georgia Sea Grant College Program, Athens, GA 30602-3636, USA; 3University of New Brunswick, Saint John, NB, E2L 4L5, Canada; 4Marine and Fishery Dept. of Hainan Province, Haikou, Hainan, P. R. China; 5The University of Georgia, Athens, GA 30602-3636, USA One of the most difficult tasks resource managers face is understanding the carrying capacity of coastal waters for aquaculture. Aquaculture, like many other human activities, can threaten coastal waters. Aquaculture producing shrimp and finfish depends on supplemental feeding and can contribute to eutrophication. A second type, involving shellfish and macroalgae, extracts plankton and nutrients from surrounding waters, and can have a significant positive impact on moderately eutrophic waters. Ecosystem modeling offers a 3-dimensional physical, chemical and biological simulation that can help understand and predict the impacts of aquaculture on coastal embayments. Such a model is being explored for Xincun Bay (22 km2), which is located in southeastern Hainan Province, China. Aquaculture in Xincun Bay includes 6500 fish pens, 100 ha of shrimp ponds, pearl oyster culture rafts and Kappaphycus alvarezii culture that produces 2,000 mt (Oct.-May). The surrounding area has ~ 15,000 people and Xincun City is a major offshore fishing and tourist center. The annual nitrogen and phosphorus removal capacity of Kappaphycus in Xincun Bay may have been in the order of 53.8 and 3.7 mt, respectively, during the 1999-2000 growing season. Lian Bay (~ 15 km2), a nearby bay with only Kappaphycus and pearl oyster culture (and little anthropogenic input), has a macroalgal production of 1,500 mt annually. The annual nitrogen and phosphorus removal capacity of Kappaphycus here may have been in the order of 25 and 0.33 mt, respectively. Our prototype model may hold the promise for showing the importance of integrating seaweed culture activities in the maintenance and health of coastal embayments. [source] Sedimentation of Soils from Three Physiographic Regions of Alabama at Different SalinitiesJOURNAL OF THE WORLD AQUACULTURE SOCIETY, Issue 4 2009Gulnihal Ozbay This study evaluated the rate of sedimentation from water under various salinities, over a time period of 72 h. The particles come from soils that are commonly found in shrimp growing areas of Alabama: Black Belt Prairie, Piedmont Plateau, and Upper Coastal Plain. Different salinity treatments and settling times resulted in significant differences (P, 0.05) in the reduction of turbidity and TSS for each soil type. Solutions containing 2 ppt salinity had a similar rate of turbidity reduction as the solutions with 5, 10, or greater ppt treatments. Concentrations of turbidity and TSS decreased rapidly between 1 and 12 h of sedimentation; very little decline was observed during the time intervals 12,72 h. Higher salinity treatments yielded settling patterns similar to the 2 ppt salinity treatment. After 1 h, turbidity was removed by 65% in the control compared with 85% salinity treated samples. Variations in turbidity and TSS among the three sediments suggest that finer particles, the Piedmont Plateau soils, settled at a slower rate than larger particles. This difference occurs because the percentage of turbidity and TSS removed was significantly higher in mineralized waters compared to freshwater. Therefore, a small amount of salt, 2 ppt, can be used in pond aquaculture treatments to reduce the turbidity and TSS concentrations in shrimp ponds. [source] Nitrite Toxicity to Litopenaeus vannamei in Water Containing Low Concentrations of Sea Salt or Mixed SaltsJOURNAL OF THE WORLD AQUACULTURE SOCIETY, Issue 4 2004Anthony Sowers The uptake, depuration and toxicity of environmental nitrite was characterized in Litopenaeus vannamei exposed in water containing low concentrations of artificial sea salt or mixed salts. In 2 g/L artificial sea salts, nitrite was concentrated in the hemolymph in a dose-dependent and rapid manner (steady-state in about 2 d). When exposed to nitrite in 2 g/L artificial sea salts for 4 d and then moved to a similar environment without added nitrite, complete depuration occurred within a day. Increasing salinity up to 10 g/L decreased uptake of environmental nitrite. Nitrite uptake in environments containing 2 g/L mixed salts (combination of sodium, potassium, calcium and magnesium chlorides) was similar to or lower than rates in 2 g/L artificial sea salt. Toxicity was inversely related to total dissolved salt and chloride concentrations and was highest in 2 g/L artificial sea salt (96-h medial lethal concentration = 8.4 mg/L nitrite-N). Animals that molted during the experiments did not appear to be more susceptible to nitrite than animals that did not molt. The shallow slope of the curve describing the relationship between toxicity and salinity suggests that management of nitrite toxicity in low-salinity shrimp ponds by addition of more salts may not be practical. [source] Factors Affecting Sediment Oxygen Demand in Commercial Channel Catfish PondsJOURNAL OF THE WORLD AQUACULTURE SOCIETY, Issue 3 2004James A. Steeby Sediment oxygen demand (SOD) measured in 45 commercial channel catfish ponds in northwest Mississippi using in situ respirometry (N = 167) ranged from 63 to 1,038 mg/m2 per h. Mean SOD in this study (359 mg/m2 per h) was greater than that reported previously for catfish ponds but was similar to SOD in semi-intensive marine shrimp ponds. Nine variables were selected and measured to assess their relative importance in accounting for variation in SOD. Six variables were included in multiple regression models that explained slightly more than half of the variation in SOD. These variables were: dissolved oxygen concentration at the beginning of respirometry incubation:, particulate organic matter concentration in water above the sediment surface: organic carbon concentration at the immediate sediment-water interface (flocculent or F-layer) combined with the upper 2 cm of sediment (S-layer); organic carbon concentration in the mature (M) underlying sediment layer: water temperature: and total depth of accumulated sediment. Sediment oxygen demand was most sensitive to changes in dissolved oxygen concentration in the overlying water, particulate organic matter concentration in the water, and the concentration of organic carbon in the combined flocculent and upper sediment (F+S) layer. Models for SOD in this research predict that the mass of sediment below the upper 2-cm surface layer on average contributes only ,20% of total SOD. Stratification and normal daily fluctuation of dissolved oxygen concentration in eutrophic culture ponds likely limit expression of sediment oxygen demand. Maintaining aerobic conditions at the sediment-water interface will minimize accumulation of organic matter in pond sediment. [source] Changes in the Concentration of Nutrients and Other Chemical Properties of Shrimp Pond Soils as a Function of Pond UseJOURNAL OF THE WORLD AQUACULTURE SOCIETY, Issue 3 2002Gad Ritvo Several soil nutrients, pH, organic carbon, and total soluble salts from the upper 10 cm of soil samples from 72 shrimp ponds in Texas were analyzed. Large increases in sediment concentrations of C, N, Mg, K, Na, Fe, Mn, Zn, Cu, B, nitrate, and water-soluble salts was observed after one production cycle, followed by an asymptotic increase in older ponds. An approximately linear increase in soil concentration of S and P with pond age was observed. The pH showed a marked decrease in ponds that had been used for one production cycle, but stabilized in older ponds. No correlation between Ca and growing cycle was observed. Calculated recovery rates for elements supplied in feed were less than 10% in several cases and 15% for P. No measurable negative effect on shrimp production by the increase of elemental concentrations was measured. [source] Impact of aquaculture on mangrove areas in the northern Pernambuco Coast (Brazil) using remote sensing and geographic information systemAQUACULTURE RESEARCH, Issue 6 2010Ariana Silva Guimarães Abstract The conversion of mangrove areas into shrimp farming ponds has been indicated as the main activity responsible for the reduction in the area of this ecosystem along the northeastern coast of Brazil. The present study was conducted using remote sensing methods and a geographical information system with the aim of quantifying the participation of this activity in the reduction of the mangrove areas along the northern coast of the State of Pernambuco (northeast, Brazil), where shrimp farming has been implanted in last recent years. From 1973 to 2005, there was reduction of about 2.052 ha of mangrove, 197 ha of which were converted into shrimp ponds. Thus, the real contribution of shrimp farming to this reduction was just 9.6% of the total area. Other anthropogenic activities, such as agriculture, urban expansion and tourism, contributed greatly to the reduction in the mangrove areas along the northern coast of the State of Pernambuco. [source] Effects of water exchange and abiotic factors on zooplankton and epibenthic fauna in shrimp pondsAQUACULTURE RESEARCH, Issue 14 2006Frank E Coman Abstract Assemblages of zooplankton and epibenthic invertebrates were collected from a commercial Penaeus monodon (Fabricius) pond at fortnightly intervals over an entire grow-out season. The pond inlet and outlet water were also sampled intensively over three 1-week periods throughout the season. Before stocking the ponds with shrimp postlarvae, copepods dominated the zooplankton. Immediately after the ponds were stocked, there was a rapid decline in zooplankton numbers, particularly the dominant larger copepods, suggesting heavy predation by shrimp postlarvae. For the rest of the season, barnacle nauplii were the dominant zooplankton component in the pond. Pond water exchanges had little detectable influence on the composition or density of the zooplankton assemblage. Instead, the dominance of barnacle nauplii appeared to have been maintained by steady recruitment due to barnacle reproduction in the pond. While changes in the biomass of pond zooplankton were not correlated with physico-chemical characteristics, changes in density were positively correlated with temperature, and negatively correlated with pH, dissolved oxygen and secchi disc readings. Epibenthic faunal density peaked at the end of the season, while the biomass peaked during the middle part of the season. Sergestids (Acetes sibogae Hansen) were the most abundant epibenthic taxa. No correlations were found between physico-chemical parameters and epibenthic fauna biomass or density. Abundances of epibenthic fauna were not related to zooplankton densities, suggesting that trophic interactions between these assemblages is not important. No Acetes were captured in samples of outlet water, and only on a single occasion were large numbers captured in the inlet water; after this, there was a notable increase in the number of Acetes in the pond. This evidence, together with the lack of an increase in the size of Acetes during the season, suggests that water exchange is an important but unpredictable source of recruitment of epibenthic fauna into the pond. The results emphasize the benefits of ensuring that appropriate zooplankton assemblages have been introduced into the ponds, when they are filled, to support the shrimp immediately after stocking. This will depend on the initial inoculum and may be difficult to manipulate with water exchanges once established. Assemblages of epibenthic fauna appear more likely to change with exchanges and may need to be monitored across the season, particularly if their presence reduces production through adverse impacts such as competition with postlarvae, introduction of disease or deteriorated water quality. [source] | ||||||||||