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  1. Pond Fish Culture Practices in Nigeria

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    J.A. Akankali

    2011-06-01

    Full Text Available Pond fish culture practices in Nigeria was reviewed to refresh the minds of fish and other interested stake holders on some basic principles involved in pond fish culture. Fish pond system is the commonest agricultural techniques in the Niger Delta Region of Nigeria. Profit making, job creation, provision of raw materials for several industries and increase in foreign exchange earnings are some benefits. However, loss of land and introduction some water borne diseases are some disadvantages in pond fish culture. This articles reviews the fish pond management processes, stocking of ponds, feeding of fish, types of culture, fish farming combined with other branches of agriculture, rearing of fish for purposes other than food, other fish culture, types of fish used for fish culture in central east Africa, general biology of the species of value in fish culture and suitable combinations of fish for stocking to reawaken the minds of individuals, companies and government on the need to develop pond fish culture in Nigeria.

  2. Photosynthesis and fish production in culture ponds

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    Szyper, J.P.

    1995-12-31

    The widely-cultured Nile tilapia, Oreochromis niloticus, has been the major species used in standardized experiments by the Pond Dynamics/Aquaculture Collaborative Research Support Program (PD/ACRSP). Yields of Nile Tilapia from fertilized, unfed ponds have served as a bioassay for effectiveness of pond management protocols developed during worldwide tropical experiments. Yield rates near 10 T/ha/y can be achieved without feed inputs in ponds which maintain high standing stocks of phytoplankton and exhibit high rates near 10 T/ha/y can be achieved without feed inputs in ponds which maintain high standing stocks of phytoplankton and exhibit high rates of primary production. Fish production is related to daytime net photosynthetic production, but it is not clear whether production of food materials or oxygen is the more direct influence. Excessively high standing stocks of phytoplankton are not the best net producers, and increase and risk of nighttime oxygen depletion. Fish readily grow to individual sizes of 200-300 g/fish in fertilized ponds, which is sufficient market size in many locations. Supplemental feeding of caged or free-ranging fish greatly accelerates growth beyond 300 g and potentiates high areal yields; the PD/A CRSP has also developed efficient feeding regimes and shown that supplemental feeding need not begin before fish reach 200 g weight. High standing stocks of phytoplankton and high photosynthetic rates in eutrophic ponds make study of photosynthesis possible without radioisotopes. Such ponds also exhibit complete extinction of incident solar radiation within shallow depths, and vertical temperature structure resembling that of deeper bodies of water. These characteristics make ponds useful as microcosms for study of some aspects of photosynthesis in natural waters.

  3. PERFORMANCES OF TIGER SHRIMP CULTURE IN ENVIRONMENTALLY FRIENDLY PONDS

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    Taufik Ahmad

    2016-10-01

    Full Text Available Mangrove ecosystem plays an obvious role in maintaining the biological balance in the coastal environment where shrimp ponds are usually constructed. The removal of mangroves around shrimp ponds has frequently brought about harvest failure. The study evaluated the performance of tiger shrimp culture in ponds provided with water from a water body where there was mangrove vegetation (hereafter mangrove reservoir. Twelve ponds, each measuring 2,500 m2, were filled with seawater from the mangrove reservoir until the water depth of 100 cm and then stocked with 20-40 PL/m2. In the first six ponds, the bottom water was released into the reservoir when the water depth reached 140 cm and then the water depth was maintained at 100 cm. In the second six ponds, the water was released from the ponds until the water depth reached 60 cm and then refilled with reservoir water until a depth of 100 cm. Both treatment ponds received water from the reservoir which also received the wastewater. The feeds for the shrimps were broadcast into the ponds twice a day to meet the 3% shrimp biomass requirement, which adjusted every other week through sampling. The result showed that mangrove  vegetation is capable of removing excessive nutrients, up to 70% for NO3- N and NH4 +-N, reducing PO4 =-P fluctuation, and producing bioactive  compounds. In the second treatment ponds, shrimp mortality started to occur in day 28 and most died by day 54 after stocking due to white spot disease outbreak. Mass mortality took place 54 days after stocking in two out of six of the first treatment ponds.

  4. Pond culture of seaweed Sargassum hemiphyllum in southern China

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    YU Zonghe; HU Chaoqun; SUN Hongyan; LI Haipeng; PENG Pengfei

    2013-01-01

    The seaweed Sargassum hemiphyllum is widely distributed throughout the coastal waters of Asia and has high commercial value.In recent years,its natural biomass has declined due to over-exploitation and environmental pollution.To seek for a feasible way to culture this seaweed efficiently,we designed a simple long-line system in a shrimp pond for the culture during winter,and the growth and nutritional composition of the seaweed were examined.Results show that the culture system was durable and flexible allowing S.hemiphyllum to grow vertically offthe muddy bottom of the pond.Although the length of pondcultured S.hemiphyllum was inhibited by water depth,the weight-specific growth rate ((1.65±0.17)%/d)was nearly three times higher than that of wild plants ((0.62±0.19)%/d).The crude protein (6.92%±0.88%)and ash content (21.52%±0.07%) of the pond-cultured seaweed were significantly lower than those of the wild plants (9.38%±0.43% and 26.93%±0.07%,respectively); however,crude fat (1.01%±0.04%) was significantly higher than that of the wild plants (0.87%±0.02%).In addition,the nutritional composition of both pond-cultured and wild S.hemiphyllum was comparable to or even higher than those of other common seaweeds being used as food and/or aquaculture fodder.Future studies shall be focused on the impact of environmental parameters on its growth and nutritional composition.

  5. Pond culture of seaweed Sargassum hemiphyllum in southern China

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    Yu, Zonghe; Hu, Chaoqun; Sun, Hongyan; Li, Haipeng; Peng, Pengfei

    2013-03-01

    The seaweed Sargassum hemiphyllum is widely distributed throughout the coastal waters of Asia and has high commercial value. In recent years, its natural biomass has declined due to over-exploitation and environmental pollution. To seek for a feasible way to culture this seaweed efficiently, we designed a simple long-line system in a shrimp pond for the culture during winter, and the growth and nutritional composition of the seaweed were examined. Results show that the culture system was durable and flexible allowing S. hemiphyllum to grow vertically off the muddy bottom of the pond. Although the length of pondcultured S. hemiphyllum was inhibited by water depth, the weight-specific growth rate ((1.65±0.17)%/d) was nearly three times higher than that of wild plants ((0.62±0.19)%/d). The crude protein (6.92%±0.88%) and ash content (21.52%±0.07%) of the pond-cultured seaweed were significantly lower than those of the wild plants (9.38%±0.43% and 26.93%±0.07%, respectively); however, crude fat (1.01%±0.04%) was significantly higher than that of the wild plants (0.87%±0.02%). In addition, the nutritional composition of both pond-cultured and wild S. hemiphyllum was comparable to or even higher than those of other common seaweeds being used as food and/or aquaculture fodder. Future studies shall be focused on the impact of environmental parameters on its growth and nutritional composition.

  6. Modified extensive pond culture of Litopenaeus vannamei for sustainable shrimp culture in the Philippines

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    Cecilia J. Jaspe

    2011-06-01

    Full Text Available The shrimp culture industry provides huge revenues to most aquaculture producing countries,but it is also beset with problems that hamper its sustainability. In the present study, we described amodified extensive pond culture method for white shrimp, Litopenaeus vannamei in the Philippines duringthe wet and dry months. One hectare earthen ponds were prepared and added with organic and/orinorganic fertilizers to stimulate natural food production. The ponds were stocked with L. vannameipostlarvae (PL at a density of 4 PL m-2. A zero-water exchange system of pond management was doneduring the first two months of culture followed by a bi-weekly water exchange until harvest. No artificialfeeding was given during the culture period, instead, the ponds were applied with inorganic fertilizerevery month to ensure continuous supply of natural food. During the culture period, the shrimpsappeared healthy and no disease outbreaks were observed. All the physico-chemical parameters of thewater in the pond were within the optimum range required for shrimp farming and the phytoplanktonpopulation was predominantly green microalgae (Chlorophyta. The shrimps were harvested after 3 to3.5 months of culture or when they reached an average body weight of 13-15 g, with moderate to highsurvival rates depending on the prevailing climatic conditions.

  7. The laboratory environmental algae pond simulator (LEAPS) photobioreactor: Validation using outdoor pond cultures of Chlorella sorokiniana and Nannochloropsis salina

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    Huesemann, M.; Williams, P.; Edmundson, S.; Chen, P.; Kruk, R.; Cullinan, V.; Crowe, B.; Lundquist, T.

    2017-09-01

    A bench-scale photobioreactor system, termed Laboratory Environmental Algae Pond Simulator (LEAPS), was designed and constructed to simulate outdoor pond cultivation for a wide range of geographical locations and seasons. The LEAPS consists of six well-mixed glass column photobioreactors sparged with CO2-enriched air to maintain a set-point pH, illuminated from above by a programmable multicolor LED lighting (0 to 2,500 µmol/m2-sec), and submerged in a temperature controlled water-bath (-2 °C to >60 °C). Measured incident light intensities and water temperatures deviated from the respective light and temperature set-points on average only 2.3% and 0.9%, demonstrating accurate simulation of light and temperature conditions measured in outdoor ponds. In order to determine whether microalgae strains cultured in the LEAPS exhibit the same linear phase biomass productivity as in outdoor ponds, Chlorella sorokiniana and Nannochloropsis salina were cultured in the LEAPS bioreactors using light and temperature scripts measured previously in the respective outdoor pond studies. For Chlorella sorokiniana, the summer season biomass productivity in the LEAPS was 6.6% and 11.3% lower than in the respective outdoor ponds in Rimrock, Arizona, and Delhi, California; however, these differences were not statistically significant. For Nannochloropsis salina, the winter season biomass productivity in the LEAPS was statistically significantly higher (15.2%) during the 27 day experimental period than in the respective outdoor ponds in Tucson, Arizona. However, when considering only the first 14 days, the LEAPS biomass productivity was only 9.2% higher than in the outdoor ponds, a difference shown to be not statistically significant. Potential reasons for the positive or negative divergence in LEAPS performance, relative to outdoor ponds, are discussed. To demonstrate the utility of the LEAPS in predicting productivity, two other strains – Scenedesmus obliquus and Stichococcus minor

  8. Effect of culture intensity and probiotics application on microbiological and environmental parameters in Litopenaeus vannamei culture ponds.

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    Patil, Prasanna Kumar; Muralidhar, M; Solanki, Haresh G; Patel, Pretesh P; Patel, Krishna; Gopla, Chavali

    2016-01-01

    The present study examined the complex interaction among stocking density and extent of probiotic use with production and environmental parameters in Litopenaeus vannamei culture ponds to suggest suitable management strategies. The study was conducted inL. vannamei culture ponds with stocking density of 35 nos sq m(-1) (Group I) and 56 nos sq m(-1) (Group II) and probiotic application @16.5 kg ha(-1) and 157 kg ha(-1), respectively. There was no significant difference noted between the two groups of ponds in respect to ammonia oxidizing bacteria (AOB) in sediment and nitrite oxidizing bacteria (NOB) in water samples, whereas significantly higher levels of AOB in water samples of high intensity culture ponds (Group II) and NOB in sediment samples of Group I were observed. The levels of sulphur oxidizing bacteria (SOB) and sulphur reducing bacteria (SRB) in Group I pond water and in Group II sediment were significantly higher than their corresponding levels in the other group. In both the groups, ammonia, nitrite and sulphide concentrations were below toxic limits prescribed for shrimp farming. Comparing the production parameters at harvest revealed that low intensity culture ponds (Group I) had higher growth rate, average body weight and significantly lower FCR and higher survival rate than high intensity culture ponds (Group II). The results indicated that application of microbial products in higher quantities did not benefit significantly, and there is a need to regulate quantum and schedule of biological product usage for economically sustainable shrimp culture.

  9. Is intensification a viable way for pond culture in Central and Eastern Europe?

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    Gergő Gyalog

    2011-12-01

    Full Text Available Today’s Central and Eastern European aquaculture is based on low production intensity pondculture dominated by traditional extensive and semi-intensive carp-based polyculture technologies, useof complete feeds in pond culture is not prevalent. Meanwhile pond culture in other parts of the Worldhas gone through an intensification process, nowadays high-intensity monoculture technologies dominatein pond farming. Use of complete feeds and application of higher stocking rates have doubled-tripledyields compared to traditional extensive, semi-intensive farming methods. Economic analysis of Asianfarms shows that intensification leads to increased profits per unit area and decreased profitability. Thecalculation of financial results of fish farming technologies of different intensity level show the sameeffect of intensification on viability in Hungary as in Asia: high feeding and stocking rate result inoutstanding profit per unit area and decreased profit margin at the same time. Rising land prices (andrents, fees for usage of water, decrease in area-based subsidies can push the Central and EasternEuropean pond aquaculture toward intensification as high intensity fish rearing in ponds may offer goodalternative for those farmers who have limited access to land (pond area and water. However one musttake the increased risks of high intensity and must have good managing abilities and farming expertisewith special regard to water quality and biomass management.

  10. Harmful Ciliates and Dominant Genus in Culture Ponds of Young Abalone

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    黄建荣; 徐润林; 廖家遗

    2004-01-01

    By using the methods of qualitative and quantitative analysis, the species composition and dominant genus of harmful, ciliates in young abalone culture ponds are studied. Totally 68 species of ciliates, belonging to 3 classes, 16 orders and 46 genus, are found. The dominant ciliate species are Aspidisca leptaspis, Vorticella sp. and Euplotes rariseta. During the young abalone cultivation, the numbers of young abalones increase first,and then show a trend of decreasing. The relationship between the density and composition of ciliates and the density of algae in the young abalone culture ponds is also discussed.

  11. Effect of co-culture of Chinese shrimp ( Fenneropenaeus chinensis) and sea cucumber ( Apostichopus japonicus Selenka) on pond environment

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    Yu, Haibo; Gao, Qinfeng; Dong, Shuanglin; Sun, Yongjun; Wang, Fang

    2016-10-01

    Monoculture of sea cucumber (pond S) and polyculture of shrimp with sea cucumber (pond SS) were established to evaluate the effect of shrimp on the environmental conditions of sea cucumber farming pond. Contributions of sediment organic matter (SOM2) resuspended from benthic sediment and the suspended particulate organic matter (SPOM) deposited from the water column to the precipitated organic matter (SOM1) collected with sediment traps were estimated with carbon stable isotope analysis. The results showed that the levels of SPOM and SOM2 in pond SS significantly decreased in comparison with those in pond S at the end of experiment ( P culturing shrimp in sea cucumber farming pond could purify the farming water. Carbon stable isotope analysis showed that the proportion of SOM2 in SOM1 in pond SS (84.97% ± 0.38%) was significantly lower than that in pond S (95.20% ± 0.30%) ( P < 0.05), suggesting that the resuspension of organic matter from benthic sediment into overlying water was reduced in polyculture pond. In contrast, the proportion of SPOM in SOM1 in pond SS (15.03% ± 0.38%) was significantly higher than that in pond S (4.80% ± 0.30%) ( P < 0.05), indicating that the sedimentation of SPOM from water column was enhanced in pond SS owing to the biodeposition effect of shrimp.

  12. Investigation on novel raceway pond with inclined paddle wheels through simulation and microalgae culture experiments.

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    Zeng, Fanxue; Huang, Jianke; Meng, Chen; Zhu, Fachao; Chen, Jianpei; Li, Yuanguang

    2016-01-01

    The open raceway ponds are nowadays the most used large-scale reactors for microalgae culture. To avoid the stacking of microalgae, the paddle wheels are the most widely used to circulate and mix the culture medium. In this paper, a numerical simulation using computational fluid dynamics (CFD) was used to investigate the hydrodynamic characteristics of open raceway ponds with different types of paddle wheels (the traditional paddle wheels and the novel paddle wheels with specially inclined angle of the blades). The particle image velocimetry (PIV) was used to validate the reliability of the CFD model. The CFD simulation results showed that the novel raceway pond with 15° inclined angle of the blades had the best mixing efficiency under the same power consumption. Lastly, the results of microalgae culture experiments showed that the growth rates of Chlorella pyrenoidosa in the novel raceway pond with 15° inclined angle of the blades were higher than those in the traditional reactor. The results of the culture experiments and CFD simulations were identical with each other. Therefore, a novel paddle wheel with 15° inclined angle of the blades was obtained for better microalgae cultivation.

  13. Limnology of Kharland (saline) ponds of Ratnagiri, Maharashtra in relation to prawn culture potential.

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    Saksena, D N; Gaidhane, D M; Singh, H

    2006-01-01

    The coastal saline soils, Kharlands, have great potential for their use in aquaculture. This study has been taken up to understand the limnology of the ponds in Kharland area for assessing their prawn culture potential. This study was carried out during September, 1999 to August, 2001. Each Kharland pond has an area of 0.045 hectare. During the study, depth of pond water was 47.7 to 120.0 cm, temperature varied from 25.7 to 34.5 degrees C; transparency from nil to 65.0 cm; specific conductivity from 1.78 to 94.5 microS.cm(-1); total dissolved solids from 0.89 to 27.55 ppt; pH 5.42 to 8.25; dissolved oxygen 1.6 to 8 mg.l(-1); free carbon dioxide 10.00 to 44.00 mg.l(-1); total alkalinity 5.00 to 142.00 mg.l(-1); salinity 0.45 to 39.55 ppt; total hardness 245.00 to 5945.00; calcium 56.05 to 1827.6; magnesium 110.74 to 4507.75 mg.l(-1); dissolved organic matter 1.45 to 9.68 mg.l(-1); ammonia 1.00-8.00 microg.l(-1); nitrite nil to 20.00 micro l(-1) and nitrate 7.5 to 17.5 microg.l(-1). These Kharland ponds are unique in physio-chemical characteristics during their seasonal cycle. From July to October, these ponds have nearly freshwater while from November to May pond water becomes saline. Thus, there is a great possibility of taking up monoculture of both the freshwater and brackish water prawns as well as polyculture of prawns and fishes in the Kharland ponds.

  14. Carbon, nitrogen, and phosphorus budget in scampi (Macrobrachium rosenbergii) culture ponds.

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    Sahu, Bharat Chandra; Adhikari, Subhendu; Mahapatra, Abhijit S; Dey, Lambodar

    2013-12-01

    Experiments were conducted for the study of nutrient budget in ten farmer's ponds (0.2-0.5 ha) in Orissa, India with a mean water depth of 1.0-1.2 m. Scampi (Macrobrachium rosenbergii) were stocked in these ponds at stocking density of 3.75-5.0/m(2). The average initial body weight of scampi was 0.02 mg. The culture period was for 4 months. Feed was the main input. Total feed applied to these ponds ranged from 945 to 2261 kg pond/cycle (crop). The feed conversion ratio varied 1.65 to 1.78. In addition to feed, rice straw, urea, and single super phosphate were applied to these ponds in small amounts for plankton production. At harvest time, the average weight of scampi varied from 60-90 g. The budget showed that feed was the major input of nitrogen (N), phosphorus (P), and carbon in these ponds. The inorganic fertilizer (urea and single super phosphate), organic fertilizer (rice straw and yeast extract), and inlet water, either from the initial fills or from rainwater, were the source of all other N, P, and organic carbon (OC) to these ponds. Total N applied to these ponds through all these inputs ranged from 44.45 to 103.98 kg N per crop, 12.23 to 28.79 kg P per crop, and from 381.54 to 905.22 kg OC per crop, respectively. Among all the inputs, feed alone accounted for 95.34 % N, 97.98 % P, and 94.27 % OC, respectively. Recovery of 16.34 to 38.66 kg N (average 29.27 kg), 1.28 to 3.02 kg P (average 2.29 kg), and 63.21 to 149.51 kg OC (average 113.20 kg), respectively, by the scampi harvest were observed in these ponds. Thus, harvest of scampi accounted for recovery of 35.18 to 39.01 (average 36.85%) of added N, 10.09 to 10.97 (average 10.44%) of added P, and 7.57 to 17.12 (average 16.34%) of added OC, respectively.

  15. Culture of Eriocheir sinensis Larvae in Ponds in Greenhouse

    Institute of Scientific and Technical Information of China (English)

    Guoliang RUAN; Liangcheng HU; Hai ZHOU; Dawen MA; Yabin TANG

    2016-01-01

    A total of 15 pools were selected from a greenhouse, and they were randomly and evenly divided into three groups. In each group, one stocking density of Eriocheir sinensis was arranged. The results showed that after 45-d culture, the crab number per kilogram reached about 300 with survival rate of about 20%; the initial stocking density had significantly effect on the body size of E. sinensis on sel , instead on the survival rate of E. sinensis larvae. Therefore, it is feasible to conduct the culture of E. sinensis larvae in a pool in greenhouse.

  16. Nutrient budgets and effluent characteristics in giant freshwater prawn (Macrobrachium rosenbergii) culture ponds.

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    Adhikari, Subhendu; Sahu, Bharat Chandra; Mahapatra, Abhijit S; Dey, Lambodar

    2014-05-01

    It is important to understand nutrient budgets of aquaculture practices for efficiency of input resources and to utilize all output nutrient sources. The aim of the present study was to develop a nutrient budget for giant freshwater prawn (Macrobrachium rosenbergii) culture ponds. The study was conducted in farmer's ponds (0.25-0.5 ha) of Odisha, India, and the results showed that feed accounted 97% total nitrogen (N), 98.7% total phosphorus (P) and 90% total organic carbon (OC), respectively. The harvested prawn accounted for recovery of 37% N, 10% P and 15% OC, respectively. The N, P and OC accumulated in sediment were 52%, 76%, and 65%, respectively. Nutrient loads in the effluents were 2.22 ± 0.66 kg inorganic N, 0.40 ± 0.15 kg P, and 21.01 ± 6.4 kg OC per ton of prawn production. The present study implicated that high nutrient values observed in both water and sediment provide important opportunities for nutrient reuse through pond sediment applications to croplands as an organic manure, as well as pond water irrigation to crops as a "liquid fertilizer".

  17. [Seasonal variation of functional diversity of aquatic microbial community in Apostichopus japonicus cultural pond].

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    Yan, Fa-Jun; Tian, Xiang-Li; Dong, Shuang-Lin; Yang, Gang

    2014-05-01

    The functional diversity of aquatic microbial communities in sea cucumber (Apostichopus japonicus) cultural ponds was examined in this paper. The Biolog plate technique and redundancy analysis (RDA) method were used to evaluate seasonal changes and their relationships with environmental factors. The results showed that both total amount and types of carbon sources utilized by microbes in the sea cucumber cultural ponds varied seasonally, and were the highest in summer and lowest in winter, with polymers being the main type of carbon sources. Principal component analysis revealed that the carbon utilization diversity of the microbial communities varied significantly over the seasonal courses. A total of 10 categories of carbon sources were significantly related to the principal component 1, among which were polymers, carbohydrates, carboxylic acids, amino acids, and amines. Significant seasonal changes were detected for all carbon utilization diversity indices of the microbial communities, including Shannon, McIntosh, Simpson, and S-E. However, seasonal variations were different among the microbial diversity indices. RDA analysis revealed that TP, NO(3-)-N, TN, and PO4(3-)-P were the critical environmental factors influencing the seasonal changes in functional diversity of aquatic microbial community in sea cucumber cultural ponds.

  18. Nile tilapia culture on domestic effluent treated in stabilization ponds.

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    Clovis Matheus Pereira

    2009-03-01

    Full Text Available The performance and filet quality of tilapias (Oreochromis niloticus culture in effluent stabilization lagoons was tested at the densities of 3 fish/m2 (T3, 7 fish/m2 (T2 and 7 fish/m2 in clean water + diet (T1 with 3 repetitions in tanks of 2.57m2 and 0.60m of water column with supplemental aeration. Fish culture in clean water plus diet (T1 presented the highest growth. The higher density T3 (7/m2 compared to T2 (3/m2 did not result in any difference of total production (p > 0.05 but this was compensated by the increased individual fish growth rate at lower density. The conditions that sustain fish survival culture with ETE effluent were attested by the high survival (> 90% under both treatments, but only 10% of the water samples from T2 and T3 N-total ammonium was favorable for fish growth (< 2.0mg/L. The rearing system improved the effluent quality, reducing the total organic nitrogen and the solids in suspension. The faecal coliforms, Salmonella sp. and Staphylococcus aureus from the effluent and fish were verified to be within the standards laid down by the World Health Organization (WHO.

  19. Myxozoan pathogens of Malaysian fishes cultured in ponds and net-cages.

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    Székely, Cs; Shaharom-Harrison, F; Cech, G; Mohamed, K; Molnár, K

    2009-01-28

    We describe new myxosporean species from Malaysian fishes cultured in pond farms and net-cages. Myxobolus omari sp. nov. and M. leptobarbi sp. nov. were found in the muscles of Pangasianodon hypophthalmus and Leptobarbus hoevenii, respectively, while plasmodia and spores of Thelohanellus zahrahae sp. nov. and Henneguya daoudi sp. nov. were detected in the gills of Barbonymus gonionotus and Trichogaster trichopterus, respectively. Plasmodia and spores found in these fishes differed from the known myxosporean species in respect of their morphology, tissue tropism and 18S rDNA structure. No major pathological changes were found, but in the future these species might pose a potential threat to more intensified fish culture.

  20. Culture of Spirogyra africana from farm ponds for long-term experiments and stock maintenance

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    Gallego, I.

    2013-01-01

    Full Text Available Spirogyra africana (Fritsch Czurda is a ubiquitous filamentous green alga that grows naturally in Andalusian farm ponds. Research on this macroalga has reported several biotechnological applications, emphasizing its value for biofuel production. However, culture media for growth of this species have not yet been tested for long-term experiments and stock maintenance. Here we test the three most common culture media cited in the literature for Spirogyra growth, i.e. HSCHU#10, sD11 and pond water, in a 10-week laboratory experiment. We compared growth rates, percentages of live filaments and number of rhizoids per filament of S. africana cultured in each medium. The effect of filament sterilization to obtain monoalgal cultures, i.e. chlorination, was also tested on its growth. After 10 weeks, S. africana grew in HSCHU#10, whilst FPW and sD11 showed poorer results. Filament chlorination prior to inoculation showed a positive effect on growth, especially several weeks after algal inoculation. Rhizoid genesis seemed to be dependent on additional external factors, but responded to chlorination positively. We recommend the use of HSCHU#10 and the surface decontamination of filamentous algae with chlorine for Spirogyra cultures, especially for long-term experiments and stock maintenance.

  1. EFFICIENCY OF CONCOMITANT APPLICATION OF ORGANIC FERTILIZERS AND CULTURED INVERTEBRATES FOR INCREASING FISH PRODUCTIVITY IN NURSERY PONDS

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    A. Tuchapska

    2014-03-01

    Full Text Available Purpose. To study the fisheries and biological indicators of young-of-the-year carp when applying fertilizer in ponds, introducing stock cultures of Daphnia magna (Straus and feeding of young-of-the-year with cultured zooplankton organisms and to evaluate the effectiveness of measures for enhancing the provision of young-of-the-year carp with natural feeds. Methodology. Stock culture of Daphnia magna was added into experimental ponds, 65 kg/ha of zooplankton, which were cultured in a pond-cultivator and cages installed in experimental ponds were used for feeding young-of-the-years in July and August. For study of nutrition and growth of young-of-the-year carp, samples were taken during regular control fish seining. Parameters of young-of-the-year carp growing and economic efficiency of measures aimed at increasing the supply of young-of-the-year carp with natural feeds were determined. Findings. Average seasonal zooplankton biomass in experimental ponds was 3,9 – 4,8 times higher than the biomass in the control pond. Natural food in the stomach content of carps from experimental ponds in June was 64,7 – 71,3 %, in July it decreased to 48.0 %, in August ― to 15,0 – 2,0 %. Natural food part in young-of-the-year diet in June was 9,3 %, in July ― 20,6 – 2,1%, in August ― 1,1 – 0,4 %. Fish productivity in experimental ponds was higher by 35,2 – 4,5% than that in the control pond. Expenditure of grain feeds for the growth of young-of-the-year carp in the control pond was 3,2 units, in the experiment it was 12,5 – 15,6 % lower. Profit from growing young-of-the-year carp in experimental ponds was 2,9 – 3,7 times higher than in the control and was 3955,2 – 5153,0 UAH/ha. Profitability of growing young-of-the-year with the use of intensification measures was 2,6 – 3,2 times higher than that in the control pond. Originality. For the first time we studied fisheries and biological indicators when growing young-of-the-year carp with

  2. [Evaluation of cultural service value of aquaculture pond ecosystem: a case study in a water conservation area of Shanghai].

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    Li, Sheng; Guo, Zong-xiang; Yang, Huai-yu; Yang, Zheng-yong

    2009-12-01

    Pond aquaculture has existed in China for thousands of years, which has not only contributed great economic value, but also presented cultural value for human beings. With the development and upgrading of Chinese economy and culture, these values will be highlighted further. To evaluate the cultural service value of pond aquaculture ecosystem would provide a scientific base to the policy-making to avoid or reduce the wrong design-making or avoid the policy-malfunction, and also, to promote the development of aquaculture and related recreational fishing industry, increase the added value of aquaculture and the income of fish-farmers, and promote the economic development of rural area. Based on the survey data from the aquaculture ponds in the water conservation area of Dianshan Lake in Qingpu District of Shanghai and the related statistical data, the cultural service value including recreational value and existence value of the aquaculture pond ecosystem in the area was estimated by means of travel cost method (TCM) and contingent valuation method (CVM). The total cultural service value of this ecosystem was about 213 million Yuan x a(-1) or 231296. 69 Yuan x hm(-2) x a(-1), being 5. 25 times of the market value of aquaculture products, among which, recreational value was about 189 million Yuan x a(-1), and existence value was about 24 million Yuan x a(-1). It was suggested that in the construction of new rural areas of Shanghai, sufficient attention should be paid on the full play of the cultural service value of aquaculture pond ecosystem.

  3. First Season Catfish Farming. A Workbook for Beginning Pond and Cage Culture of Channel Catfish. Teacher Edition and Student Edition.

    Science.gov (United States)

    Oklahoma State Board of Vocational and Technical Education, Stillwater. Curriculum and Instructional Materials Center.

    This workbook, comprised of both the teacher and student editions, presents guidelines useful for first-year catfish farmers in Oklahoma using pond or cage cultures to raise channel catfish. The teacher edition is a set of unit guidelines only. Contents include a list of suggested readings, important addresses with types of information available…

  4. Impact of maintenance of Macrobrachium rosenbergii De Man, 1879 (Crustacea, Decapoda, Palaemonidae broodstock on the water used in culture ponds

    Directory of Open Access Journals (Sweden)

    JFV. Biudes

    Full Text Available Aquaculture production generates social and economic benefits, but can also cause environmental impacts. The objectives of this study were: a to characterise the impacts caused by the maintenance of broodstock of the giant river prawn (Macrobrachium rosenbergii on the physical and chemical characteristics of the water used in culture ponds, and b to evaluate the relationship between the biomass of the prawns and the impact of culture on the water used in the ponds. Between January and December 2004, we determined, monthly, the biomass of M. rosenbergii by means of biometrics, and the physical and chemical variables of the supply and effluent water from a pond used to maintain breeding stock. The results showed that the effluent water had higher contents of chlorophyll-a, suspended particulate matter (SPM, pH, dissolved oxygen, total Kjeldahl nitrogen (TKN and dissolved Kjeldahl nitrogen (DKN, inorganic nitrogen (IN, total (TP and dissolved phosphorus (DP, and P-orthophosphate than the supply water. The highest biomass of M. rosenbergii occurred in April (127.0 g.m-2 and the lowest in August (71.5 g.m-2, and there were positive linear correlations between the biomass of the prawns and the intensity of the increases in TKN, DKN, IN, TP, and DP of the water used in the pond. The maintenance of broodstock of M. rosenbergii increased the chlorophyll-a, SPM, nitrogen, and phosphorus contents of the water in the pond. Additionally, the increase in the biomass of the prawns intensifies the export of nitrogen and phosphorus from the pond in the effluent.

  5. Isolation and risk assessment of Geotrichum spp. in the white shrimp (Litopenaeus vannamei Boone, 1931 from culture ponds

    Directory of Open Access Journals (Sweden)

    José Luis Ochoa

    2015-09-01

    Full Text Available The present study was done in order to identify the fungus invading some of the supralittoral ponds used for shrimp aquaculture in the CIBNOR facilities in La Paz, Baja California Sur (BCS, México during the summer season. From the walls and bottoms of the ponds, two strains of Geotrichum spp. were isolated and morphologically identified. Fungal adhesion towards hemocytes and primary cultures of various white shrimp (Litopeneaus vannamei tissues (gill, tegument, and gut was analyzed to determine infectivity. Extracellular protease, lipase, and amylase activity were evaluated as virulence factors. Survival of shrimp post-larvae (PL8 exposed to fungal culture supernatant or to their filaments was also investigated. The results showed that shrimp tegument cells and hemocytes were very susceptible to Geotrichum spp. invasion, and that this fungus provokes great mortality of post-larvae. Hence, Geotrichum spp. could be considered an opportunistic pathogen that might represent a serious health risk to shrimp in culture.

  6. Yearly growth and metabolic changes in earthen pond-cultured meagre Argyrosomus regius

    Directory of Open Access Journals (Sweden)

    Luis Vargas-Chacoff

    2014-06-01

    Full Text Available Metabolic modifications associated with natural environmental conditions were assessed in the meagre Argyrosomus regius cultured in earthen ponds under natural photoperiod and temperature. Juvenile specimens (90-100 g initial weight were sampled (plasma, liver and muscle every two months for 18 months (between December 2004 and May 2006. Specimens showed seasonal variations in growth rate, with the highest values in spring and summer. Plasmatic, hepatic and muscular metabolite levels and hepatic and muscular metabolic enzymes also showed significant variations throughout the year. Enzymatic activity related to carbohydrate metabolism in the liver (HK, FBPase and G6PDH showed great modifications in summer, increasing glycogenogenic pathways, while amino acid metabolism (GDH and GOT activity was enhanced in spring and summer. However lipid-related (G3PDH activity metabolic enzymes did not show a clear seasonal pattern. In muscle, enzymatic activity related to amino acid, lipid and lactate metabolism (LDH-O activity, but not carbohydrate metabolism, showed seasonal changes in parallel with changes in growth rate. Thus A. regius specimens showed a trend to grow in summer months and mobilize their energy reserves in winter. Differences in the hepatic level were observed between the first and the second year of the study, suggesting the possible existence of metabolic changes related to specimen age or size. Our results indicate that growth and metabolic responses in A. regius are environmentally dependent and that this species is a very good candidate for diversification in aquaculture.

  7. Vogesella lacus sp. nov., isolated from a soft-shell turtle culture pond.

    Science.gov (United States)

    Chou, Jui-Hsing; Chou, Yi-Ju; Arun, A B; Young, Chiu-Chung; Chen, Chaolun Allen; Wang, Jih-Terng; Chen, Wen-Ming

    2009-10-01

    A non-pigmented, Gram-negative, aerobic, rod-shaped bacterium, strain GR13(T), was isolated using nutrient agar from a water sample from a pond used for the culture of soft-shell turtles (Trionyx sinensis), Pingtung County, Taiwan. 16S rRNA gene sequence studies indicated that the novel strain formed a monophyletic branch at the periphery of the evolutionary radiation occupied by the genus Vogesella. Its closest neighbours were Vogesella indigofera ATCC 19706(T) and Vogesella perlucida DS-28(T) (both with 97.4 % gene sequence similarity). The novel isolate could be distinguished from these species by several phenotypic characteristics. The predominant fatty acids were summed feature 3 (C(16 : 1)omega7c and/or C(15 : 0) iso 2-OH; 60 %), C(16 : 0) (13.6 %) and C(18 : 1)omega7c (12.5 %). The DNA G+C content of strain GR13(T) was 63 mol%. The DNA-DNA hybridization values for the novel strain with V. indigofera and V. perlucida were <25 %. On the basis of the 16S rRNA gene sequence analysis and the chemotaxonomic and physiological data, it is concluded that strain GR13(T) represents a novel species in the genus Vogesella, for which the name Vogesella lacus sp. nov. is proposed. The type strain is GR13(T) (=BCRC 17836(T)=LMG 24504(T)).

  8. Mixed-species biofilms cultured from an oil sand tailings pond can biomineralize metals.

    Science.gov (United States)

    Golby, Susanne; Ceri, Howard; Marques, Lyriam L R; Turner, Raymond J

    2014-07-01

    Here, we used an in vitro biofilm approach to study metal resistance and/or tolerance of mixed-species biofilms grown from an oil sand tailings pond in northern Alberta, Canada. Metals can be inhibitory to microbial hydrocarbon degradation. If microorganisms are exposed to metal concentrations above their resistance levels, metabolic activities and hydrocarbon degradation can be slowed significantly, if not inhibited completely. For this reason, bioremediation strategies may be most effective if metal-resistant microorganisms are used. Viability was measured after exposure to a range of concentrations of ions of Cu, Ag, Pb, Ni, Zn, V, Cr, and Sr. Mixed-species biofilms were found to be extremely metal resistant; up to 20 mg/L of Pb, 16 mg/L of Zn, 1,000 mg/L of Sr, and 3.2 mg/L of Ni. Metal mineralization was observed by visualization with scanning electron microscopy with metal crystals of Cu, Ag, Pb, and Sr exuding from the biofilms. Following metal exposure, the mixed-species biofilms were analyzed by molecular methods and were found to maintain high levels of species complexity. A single species isolated from the community (Rhodococcus erythropolis) was used as a comparison against the mixed-community biofilm and was seen to be much less tolerant to metal stress than the community and did not biomineralize the metals.

  9. Optimization of culture model in seawater pond:concepts,principles and methods%海水池塘养殖模式优化:概念、原理与方法

    Institute of Scientific and Technical Information of China (English)

    王岩

    2004-01-01

    Currently used seawater pond culture models are evaluated, and principles and methods in optimizing pond culture model are discussed in the present paper. The author indicates that application of the traditional polyculture has been limited in single pond. Inputted nutrients such as feed and fertilizer can' t be efficiently utilized by animals cultured in a pond with the traditional polyculture, resulting in huge waste discharge, which is regarded as a pollution source to coastal regions. The author suggests it should be possible to put several seawater ponds with different stocking structures together and optimize stocking and management systemically. Compared with the traditionally polycultured seawater ponds, ecological benefits and nutrients transport in the systemically optimized ponds would be amplified. The production performance of the systemically optimized ponds, therefore, would be increased and their pollution would be reduced.

  10. Quantitative and qualitative analyses of the bacterial microbiota of tilapia (Oreochromis niloticus) cultured in earthen ponds in the Philippines.

    Science.gov (United States)

    Pakingking, Rolando; Palma, Peter; Usero, Roselyn

    2015-02-01

    The quantity and composition of the bacterial microbiota in the rearing water, sediment, gills and intestines of tilapia Oreochromis niloticus collected every 2 weeks from Day 30 to Day 120 after stocking for grow-out culture in 6 earthen brackish water ponds in the Philippines were examined. The total heterotrophic aerobic bacterial counts obtained in the water, sediment, gills and intestines of tilapia ranged from 10(3) to 10(4) c.f.u. ml(-1), 10(3)-10(5), 10(5)-10(7) and 10(4)-10(7) c.f.u. g(-1), respectively. In terms of composition, a total of 20 bacterial genera and 31 species were identified with the preponderance of gram-negative bacteria constituting 84 % of all bacterial isolates examined. Aeromonas hydrophila, Bacillus spp., Plesiomonas shigelloides, Shewanella putrefaciens, Pseudomonas fluorescens, Staphylococcus spp. and Vibrio cholerae were the dominant bacteria identified in the gills and intestine of tilapia. These bacteria also dominated in the pond sediment and rearing water, except for the nil isolation of S. putrefaciens and V. cholerae in the water samples examined, indicating that resident bacteria in the pond water and sediment congruently typify the composition of bacterial microbiota in the gills and intestine of tilapia which under stressful conditions may propel the ascendance of disease epizootics.

  11. Combined electron microscopy and vibrational spectroscopy study of corroded Magnox sludge from a legacy spent nuclear fuel storage pond

    Science.gov (United States)

    Gregson, Colin R.; Goddard, David T.; Sarsfield, Mark J.; Taylor, Robin J.

    2011-05-01

    Samples of filtered particulates and sludges, formed from corroding magnesium alloy clad uranium metal ("Magnox") fuel elements, collected from one of the legacy nuclear fuel storage ponds located at Sellafield (UK) were investigated by Environmental Scanning Electron Microscopy with Energy Dispersive X-Ray analysis (ESEM/EDX), micro-Raman spectroscopy and Fourier transform infra-red spectroscopy (FT-IR). ESEM imaging confirmed the dominant morphology to be clusters of interlocking platelets typical of brucite (Mg(OH) 2). EDX analysis was suggestive of some conversion to the related phase, hydrotalcite (Mg 6Al 2(CO 3)(OH) 16·4H 2O), due to elevated levels of Al associated with Mg. Other apparent morphologies were less commonly observed including flaky sheets, consistent with earlier stages of Magnox alloy corrosion. In a few specific cases, rods were also observed suggestive of some conversion to Mg-hydroxycarbonate phases. Discrete phases rich in U were also identified. Fluorescence in the Raman spectroscopy also indicated surface coatings of organic macromolecules and iron sulphide on hematite containing particles, attributed to microbial activity within the open air pond. Some specific differences in the solid phases between pond areas with differing conditions were apparent.

  12. Occurrence, molecular characterization, and antimicrobial susceptibility of Aeromonas spp. in marine species of shrimps cultured at inland low salinity ponds.

    Science.gov (United States)

    Yano, Yutaka; Hamano, Kaoru; Tsutsui, Isao; Aue-Umneoy, Dusit; Ban, Masatoshi; Satomi, Masataka

    2015-05-01

    We aimed to document the risk of Aeromonas spp. in marine shrimp species cultured in inland low salinity ponds in Thailand. In 14 of 18 shrimp samples retrieved from inland grow-up ponds, Aeromonas spp. were detected at ranges from 4667 to 1,500,000 CFU/g body weight. The phylogenetic tree constructed with the gyrB and cpn60 concatenated sequences indicated that the 87 isolates consisted of Aeromonas veronii (70%), Aeromonas aquariorum (18%), Aeromonas caviae (7%), Aeromonas jandaei (2%), and Aeromonas schubertii (2%). The potential virulence of the isolates was examined by phenotypic and PCR assays. Hemolytic activity and the extracellular activity of lipase, DNase, and gelatinase were observed in most isolates (94-99%). PCR revealed the presence of 9 genes related to virulence in the 87 isolates: act (75%), aer (74%), alt (30%), ast (1%), ascV (34%), aexT (24%), fla (92%), ela (34%), and lip (24%). The susceptibility profiles to 14 antimicrobial agents of isolates were typical for the genus, but resistance to cefotaxime, a third-generation cephalosporin, and imipenem were found in two A. aquariorum and in three A. veronii isolates, respectively. These resistances were confirmed by determining minimum inhibitory concentrations. Our results indicate that the microbiological risk posed by Aeromonas should be considered for marine shrimp species that are cultured in low-salinity ponds. These shrimps may also be a vehicle for the transfer of different genotypes of Aeromonas and antibiotic-resistant determinants to regions worldwide through trade.

  13. Ecological effects of co-culturing sea cucumber Apostichopus japonicus (Selenka) with scallop Chlamys farreri in earthen ponds

    Science.gov (United States)

    Ren, Yichao; Dong, Shuanglin; Qin, Chuanxin; Wang, Fang; Tian, Xiangli; Gao, Qinfeng

    2012-01-01

    Monthly changes in sedimentation and sediment properties were studied for three different culture treatments: sea cucumber monoculture (Mc), sea cucumber and scallop polyculture (Ps-c) and scallop monoculture (Ms). Results indicated that the survival rate of sea cucumber was significantly higher in Ps-c cultures than in Mc cultures. Sea cucumber yield was 69.6% higher in Ps-c culture than in Mc culture. No significant differences in body weight and scallop shell length were found between Ps-c and Ms cultures. The mean sedimentation rate of total particulate matter (TPM) was 72.2 g/(m2·d) in Ps-c cultures, with a maximum of 119.7 g/(m2·d), which was markedly higher than that of Mc (mean value). Sedimentation rates of organic matter (OM), total organic carbon (TOC), total nitrogen (TN) and total phosphorus (TP) in Ps-c cultures were also significantly higher than those in Mc cultures. TOC and TN contents of sediment increased rapidly in the first 5 months in Ms cultures and remained at a high level. TOC and TN contents in Mc and Ps-c cultures decreased during sea cucumber feeding seasons and increased during sea cucumber dormancy periods (summer and winter). The study demonstrates that co-culture of sea cucumber and scallop in earthen ponds is an alternative way to alleviate nutrient loads and improve water quality in coastal aquaculture systems. Moreover, it provides the additional benefit of an increased sea cucumber yield.

  14. Ecological effects of co-culturing sea cucumber Apostichopus japonicus (Selenka) with scallop Chlamys farreri in earthen ponds

    Institute of Scientific and Technical Information of China (English)

    REN Yichao; DONG Shuanglin; QIN Chuanxin; WANG Fang; TIAN Xiangli; GAO Qinfeng

    2012-01-01

    Monthly changes in sedimentation and sediment properties were studied for three different culture treatments:sea cucumber monoculture (Mc),sea cucumber and scallop polyculture (Ps-c) and scallop monoculture (Ms).Results indicated that the survival rate of sea cucumber was significantly higher in Ps-c cultures than in Mc cultures.Sea cucumber yield was 69.6% higher in Ps-c culture than in Mc culture.No significant differences in body weight and scallop shell length were found between Ps-c and Ms cultures.The mean sedimentation rate of total particulate matter (TPM) was 72.2 g/(m2.d) in Ps-c cultures,with a maximum of 119.7 g/(m2.d),which was markedly higher than that of Mc (mean value).Sedimentation rates of organic matter (OM),total organic carbon (TOC),total nitrogen (TN) and total phosphorus (TP) in Ps-c cultures were also significantly higher than those in Mc cultures.TOC and TN contents of sediment increased rapidly in the first 5 months in Ms cultures and remained at a high level.TOC and TN contents in Mc and Ps-c cultures decreased during sea cucumber feeding seasons and increased during sea cucumber dormancy periods (summer and winter).The study demonstrates that co-culture of sea cucumber and scallop in earthen ponds is an alternative way to alleviate nutrient loads and improve water quality in coastal aquaculture systems.Moreover,it provides the additional benefit of an increased sea cucumber yield.

  15. VARIOUS FACTORS AFFECTING DRESSING PERCENTAGE OF COMMERCIALLY CULTURED CYPRINID FISH IN CARP FISH PONDS IN SERBIA

    Directory of Open Access Journals (Sweden)

    Todor Marković

    2012-12-01

    Full Text Available The aim of this study was to determine the yield carcass of all categories of cyprinid fish reared in ponds in Serbia. Samples of two and three-year old carp, two-year old silver carp and grass carp were taken in the winter from a pond where the production is organized in a semi­intensive system. The three­year old carp was sampled from two ponds. In one case, it fed on barley, maize and wheat in the following proportions 40:30:30, while in the second case it fed on complete diet mixtures. Also, the samples of two­year old carp were taken from ponds where they fed on complete feed mixture. Dressing percentage was the most favourable in common carp (67%, followed by silver carp (62%, and it was the least in grass carp (60% (p<0.01. The best yield (66% was obtained in two-year old carp, followed by one-year old carp (64%, and the worst yield was determined in three-year old carp (58% (p<0.01. Carcasses yield was better in two-year old carp fed on pelleted feed (68% than in carp of the same age fed on grains (66% (p<0.01. The values of dressing percentage measured in three-year old carp reared in the semi-intensive system was 56%, and 59% in three-year old carp fed on pelleted complete feed mixture. Fish species, age, system of husbandry and diet showed a significant effect on carcasses yield. The highest dressing percentage and weight of fillets was noted in two-year old carp fed on complete feed, and it was a result of lower weight of internal organs and associated fat. The obtained results may be helpful in creating the best strategy for the selection of raw fish for fish manufacturing.

  16. Input pathways of organochlorine pesticides to typical freshwater cultured fish ponds of South China: hints for pollution control.

    Science.gov (United States)

    Zhang, Bao-Zhong; Yu, Huan-Yun; You, Jing; Zeng, Eddy Y

    2011-06-01

    Air, rain, pond water, bank soil, pond sediment, fish feed, and fish were sampled from four freshwater cultured fish ponds (FWCFPs) in rural areas within the Pearl River Delta (PRD) of South China. Compositional analyses indicated that historical residues were the main sources of DDXs (defined as the sum of dichlorodiphenyltrichloroethane (DDT), dichlorodiphenyldichloroethane (DDD), and dichlorodiphenyldichloroethylene (DDE) and 1-chloro-2,2-bis(4-chlorophenyl)ethane (p,p'-DDMU)), and hexachlorocyclohexanes (HCHs) in the FWCFPs. The input fluxes to the FWCFPs were estimated at 4.0, 1.6, 15, and -0.92 µg/m(2) ·year for DDXs and 3.8, 0.92, 2.9, and -1.4 µg/m(2) ·year for HCHs for dry deposition, wet deposition, feeding, and net air-water exchange in Dongguan, and 3.8, 1.2, 137, and -1.2 µg/m(2) ·year for DDXs and 3.6, 0.66, 5.0, and -1.0 µg/m(2) ·year for HCHs in Shunde, respectively. These results indicated that fish feed was the dominant input source of DDXs to the FWCFPs. As for HCHs, fluxes via dry deposition and feeding were similar and slightly higher than those via wet deposition. Biological effects due to the occurrence of DDXs in the FWCFPs were minimal, and consumption of freshwater fish from the PRD appeared to pose insignificant risk to human health based on some existing regulations and guidelines. Copyright © 2011 SETAC.

  17. Hydro biological Characteristics of Some Semi-intensive fish culture ponds of Lumding town of Nagaon district, Assam

    Directory of Open Access Journals (Sweden)

    Tapashi Gupta

    2013-04-01

    Full Text Available Hydrobiological assessment is useful for assessing the ecological quality of aquatic ecosystem since biological communities integrate the environmental effects of water chemistry. Ten fish ponds from Lumding town, which were under semi-intensive culture practice, were selected for hydrobiological investigations. Physico-chemical properties were studied for a period of two years from July 2009 to June 2011.Some selected parameters like pH, dissolve oxygen, free carbon dioxide, TDS , total alkalinity, total hardness, sp. Conductivity, transparency and BOD were studied on some fish pond water. P H ranges from 6.1 to8.5. Temperature ranges from 18 0 C-32 0 C. Color shows light green to dirty green. Transparency ranges 17-42cm, dissolve oxygen ranges from 3.2-8.0 ppm, total alkalinity ranges from 7.9-20.0ppm, Hardness ranges from 60-135 ppm, sp.conductance ranges from123-247µmhos/cm and BOD ranges from3.1-5.0ppm. The phytoplankton belonging to division Chlorophycae and Cyanophycae are predominant over the others and zooplanktons belonging to group Protozoa, Rotifers are predominant. . A total of 30 species of belonging to Chlorophycae. Cyanophycae were identified and a total of 20 species of Rotifera, 2 species of Cladocera and 1 genus of Copepods were found. The present study is expected to help achieve better and higher yield of fish by the fish farmer with increasing awareness regarding the hydrobiological feature of the pond and implement scientific management practices accordingly

  18. Water quality, welfare and pathology of fish cultured in sport fishing lakes and ponds from Romania

    Directory of Open Access Journals (Sweden)

    Cristin Borda

    2013-03-01

    Full Text Available Fish welfare and their health depend on a large extent on the water quality where they live.Variation in physical, chemical or biological characteristics, in limits too high or very short time,represent serious stress factors for fish. Stress factors reduce the animal’s overall resistance to pestsand diseases and increase the virulence of some pathogenic biotic agents or conditioned pathogens.This research has proposed emphasizing the impact of medial water parameters situated at the limit ofdiscomfort, or even normal limits by point of view by Order 161/2002, correlated with fish welfareassessed by relationship with some morbid states occurring in fish populations in lakes and pondsstudied. Our observations have led to identification and description of interesting episodes caused bythe impact of physical-chemical parameters of water and some biotic pathogenic agents, and theiraction over fish health. Mortality of fish was found in summer season when water quality depreciationnoted in terms of main indicators: increasing water temperatures, decrease of dissolved oxygen levels,increases in pH and organic matter decomposition which led to the installation of hypoxia.Haemorrhagic septicemia was favored by conditions of biotic stress and abiotic factors, being recordedin the case of Asian cyprinids: Ctenopharyngodon idella and Hypophthalmichthys molitrix. Due to thelack of quarantine ponds, prophylactic bathing conditions and due to other technological neglects,several frequent problems were observed, such as: bleeding and skin lesions, infestation of entire fishstock in lakes or ponds with Argulus foliaceus, infestation with Saprolegniaceae. Excessiveadministration of manure to ponds led to water degradation in short time and installation of mortalityin juvenile carp at 21 days.

  19. Culture modes and financial evaluation of two oleaginous microalgae for biodiesel production in desert area with open raceway pond.

    Science.gov (United States)

    He, Qiaoning; Yang, Haijian; Hu, Chunxiang

    2016-10-01

    Cultivation modes of autotrophic microalgae for biodiesel production utilizing open raceway pond were analyzed in this study. Five before screened good microalgae were tested their lipid productivity and biodiesel quality again in outdoor 1000L ORP. Then, Chlorella sp. L1 and Monoraphidium dybowskii Y2 were selected due to their stronger environmental adaptability, higher lipid productivity and better biodiesel properties. Further scale up cultivation for two species with batch and semi-continuous culture was conducted. In 40,000L ORP, higher lipid productivity (5.15 versus 4.06gm(-2)d(-1) for Chlorella sp. L1, 5.35 versus 3.00gm(-2)d(-1) for M. dybowskii Y2) was achieved in semi-continuous mode. Moreover, the financial costs of 14.18$gal(-1) and 13.31$gal(-1) for crude biodiesel in two microalgae with semi-continuous mode were more economically feasible for commercial production on large scale outdoors.

  20. DNA stable-isotope probing of oil sands tailings pond enrichment cultures reveals different key players for toluene degradation under methanogenic and sulfidogenic conditions.

    Science.gov (United States)

    Laban, Nidal Abu; Dao, Anh; Foght, Julia

    2015-05-01

    Oil sands tailings ponds are anaerobic repositories of fluid wastes produced by extraction of bitumen from oil sands ores. Diverse indigenous microbiota biodegrade hydrocarbons (including toluene) in situ, producing methane, carbon dioxide and/or hydrogen sulfide, depending on electron acceptor availability. Stable-isotope probing of cultures enriched from tailings associated specific taxa and functional genes to (13)C6- and (12)C7-toluene degradation under methanogenic and sulfate-reducing conditions. Total DNA was subjected to isopycnic ultracentrifugation followed by gradient fraction analysis using terminal restriction fragment length polymorphism (T-RFLP) and construction of 16S rRNA, benzylsuccinate synthase (bssA) and dissimilatory sulfite reductase (dsrB) gene clone libraries. T-RFLP analysis plus sequencing and in silico digestion of cloned taxonomic and functional genes revealed that Clostridiales, particularly Desulfosporosinus (136 bp T-RF) contained bssA genes and were key toluene degraders during methanogenesis dominated by Methanosaeta. Deltaproteobacterial Desulfobulbaceae (157 bp T-RF) became dominant under sulfidogenic conditions, likely because the Desulfosporosinus T-RF 136 apparently lacks dsrB and therefore, unlike its close relatives, is presumed incapable of dissimilatory sulfate reduction. We infer incomplete oxidation of toluene by Desulfosporosinus in syntrophic association with Methanosaeta under methanogenic conditions, and complete toluene oxidation by Desulfobulbaceae during sulfate reduction. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  1. Mixed culture of tilapia (Oreochromis niloticus) and freshwater prawn (Macrobrachium rosenbergii) in periphyton-based ponds

    NARCIS (Netherlands)

    Uddin, S.

    2007-01-01

    In recent years, the concept of periphyton-based aquaculture has been tested and applied in aquaculture. Positive effects of substrate addition for periphyton development included increasing the food supply and providing shelter for culture animals. The aim of this project was to develop a low-cost

  2. Culture et Gestion d'Etangs a Poissons d'Eau Douce (Freshwater Fish Pond Culture and Management). Appropriate Technologies for Development. Manual Series--M37.

    Science.gov (United States)

    Chakroff, Marilyn; Druben, Laurel, Ed.

    This is the French translation of a "how-to" manual, designed as a working and teaching tool for extension agents as they establish and/or maintain local fish pond operations. The manual presents information to facilitate technology transfer and to provide a clear guide for warm water fish pond construction and management. Major topic…

  3. STABILIZATION PONDS

    Directory of Open Access Journals (Sweden)

    Sunarsih Sunarsih

    2013-01-01

    Full Text Available This paper presents a model for natural syst ems used in Wastewater Treatment Plant (WWTP Sewon Bantul. The model is m odeling development, derived from the physical and biochemical phenomena involved in the biological treatment process. The numerical solution of the resulting on 13 simultaneous systems of nonlinear equations by the Quasi_Newton. Data validation is measured by facultative pond at the inlet and outlet of the pond to the concentration of b acteria, algae, zooplankton, organic matter, detritus, organic nitrogen, NH3, organi c phosphor, dissolved phosphorus, Dissolved Oxygen (DO, total coliform, faecal coliform and Biochemical Oxygen Demand (BOD. A simulation model is presented to predict performance regime steady state of domestic wastewater treatment facultative stabilization pond. The high degree of significant of at least 10% indicates that the effluent parameters can be reasonably accurately predicted.

  4. 海蜇池塘养殖生长规律的研究%Growth Laws of Pond Cultured Rhopilema esculenta

    Institute of Scientific and Technical Information of China (English)

    刘顶海; 张继红; 陈四清; 方建光; 燕敬平; 刘春胜; 高亚平; 张树森

    2011-01-01

    2010年6月上旬-8月上旬,对山东荣成靖海湾池塘养殖的海蜇生长规律进行了研究.试验结果表明:海蜇幼体放入池塘后生长迅速,从6月1 H放苗到8月1日收获海蜇,伞径从2 cm左右生长至30-40 cm,甚至可以长至50 cm.不同大小海蜇的体重(湿重)与伞径呈指数增长,方程为=0.176 x28914( R2=0.990 7).海蜇池塘养殖后期,常出现饵料不足.夜光虫大量繁殖、海月水母爆发等问题,均对池塘养殖海蜇生长造成严重影响.%From early June to early August in 2010, the growth laws of pond cultured Rhopikma escuknta in Rongcheng, Shandong province were studied. The results showed that the juveniles of Rhopikma escuknta grew fast from June 1st to August 1at and its diameter could grow from 2 cm to 30-40 cm, even up to 50 cm. The weight (wet weight) of Rhopikma escuknta with different size increased exponentially with the shed diameter by the equation of y=0.176 x2.891.4 (R2=0.990 7). Some problems such as shortage of baits, large propagation of Noctiluca scintillans and the breakout of Aurelia aurita arisen in the later period of pond culture had always occurred in late culture period, which seriously influenced the growth of Rhopikma escuknta in the pond.

  5. Frozen ponds

    DEFF Research Database (Denmark)

    Langer, M; Westermann, S.; Anthony, K. Walter

    2015-01-01

    Lakes and ponds play a key role in the carbon cycle of permafrost ecosystems, where they are considered to be hotspots of carbon dioxide CO2 and methane CH4 emission. The strength of these emissions is, however, controlled by a variety of physical and biogeochemical processes whose responses to a...

  6. Solar pond

    Science.gov (United States)

    Miller, C. G.; Stephens, J. B. (Inventor)

    1978-01-01

    Shallow pools of liquid to collect low-temperature solar generated thermal energy are described. Narrow elongated trenches, grouped together over a wide area, are lined with a heat-absorbing black liner. The heat-absorbing liquid is kept separate from the thermal energy removing fluid by means such as clear polyethylene material. The covering for the pond may be a fluid or solid. If the covering is a fluid, fire fighting foam, continuously generated, or siloons are used to keep the surface covering clean and insulated. If the thermal energy removing fluid is a gas, a fluid insulation layer contained in a flat polyethlene tubing is used to cover the pond. The side of the tube directed towards the sun is treated to block out ultraviolet radiation and trap in infrared radiation.

  7. Effects of pond draining on biodiversity and water quality of farm ponds.

    Science.gov (United States)

    Usio, Nisikawa; Imada, Miho; Nakagawa, Megumi; Akasaka, Munemitsu; Takamura, Noriko

    2013-12-01

    Farm ponds have high conservation value because they contribute significantly to regional biodiversity and ecosystem services. In Japan pond draining is a traditional management method that is widely believed to improve water quality and eradicate invasive fish. In addition, fishing by means of pond draining has significant cultural value for local people, serving as a social event. However, there is a widespread belief that pond draining reduces freshwater biodiversity through the extirpation of aquatic animals, but scientific evaluation of the effectiveness of pond draining is lacking. We conducted a large-scale field study to evaluate the effects of pond draining on invasive animal control, water quality, and aquatic biodiversity relative to different pond-management practices, pond physicochemistry, and surrounding land use. The results of boosted regression-tree models and analyses of similarity showed that pond draining had little effect on invasive fish control, water quality, or aquatic biodiversity. Draining even facilitated the colonization of farm ponds by invasive red swamp crayfish (Procambarus clarkii), which in turn may have detrimental effects on the biodiversity and water quality of farm ponds. Our results highlight the need for reconsidering current pond management and developing management plans with respect to multifunctionality of such ponds. Efectos del Drenado de Estanques sobre la Biodiversidad y la Calidad del Agua en Estanques de Cultivo.

  8. Frozen ponds

    DEFF Research Database (Denmark)

    Langer, M; Westermann, S.; Anthony, K. Walter;

    2015-01-01

    on the thermal state of the surrounding permafrost; during the freezing period they prolong the period of time during which thawed soil material is available for microbial decomposition.  This study presents net CH4 production rates during the freezing period from ponds within a typical lowland tundra landscape...... in northern Siberia. Rate estimations were based on CH4 concentrations measured in surface lake ice from a variety of waterbody types. Vertical profiles along ice blocks showed an exponential increase in CH4 concentration with depth. These CH4 profiles were reproduced by a 1-D mass balance model and the net...... (0.01 to 0.14 mgCH4 m-2 day-1). In contrast, ponds exhibiting clear signs of erosion yielded net CH4 production rates of the order of 10-7 mol m-2 s-1 (140 mg CH4 m-2 day-1). Our results therefore indicate that once a particular threshold in thermal erosion has been crossed, ponds can develop into major CH4...

  9. Big-fish-little-pond effect on academic self-concept. A cross-cultural (26-country) test of the negative effects of academically selective schools.

    Science.gov (United States)

    Marsh, Herbert W; Hau, Kit-Tai

    2003-05-01

    Academically selective schools are intended to affect academic self-concept positively, but theoretical and empirical research demonstrates that the effects are negative. The big-fish-little-pond effect (BFLPE), an application of social comparison theory to educational settings, posits that a student will have a lower academic self-concept in an academically selective school than in a nonselective school. This study, the largest cross-cultural study of the BFLPE ever undertaken, tested theoretical predictions for nationally representative samples of approximately 4,000 15-year-olds from each of 26 countries (N = 103,558) who completed the same self-concept instrument and achievement tests. Consistent with the BFLPE, the effects of school-average achievement were negative in all 26 countries (M beta = -.20, SD = .08), demonstrating the BFLPE's cross-cultural generalizability.

  10. Variation of Alkaline Phosphatase Activity in Sediments of Shrimp Culture Ponds and Its Relationship with the Contents of C, N and P

    Institute of Scientific and Technical Information of China (English)

    SU Yuepeng; MA Shen; DONG Shuanglin

    2005-01-01

    Nine enclosures (5 m × 5 m) were built in a Fenneropenaeus chinensis culture pond of Rushan Gulf in April, 2001.The probiotics and BIO ENERGIZER solution were applied for disparate treatments. Variations of alkaline phosphatase activity (APA) and its relationship with the contents of C, N and P in sediments were studied. Results show that APA of sediments increases from 3.096 nmol g-1min-1 to 5.407 nmol g-1nin-1 in culture period; the bacteria biomass is not the only factor to determine APA; the contents of total P and total organic carbon have a significant positive correlation with APA, while that of total nitrogen has a negative correlation. In addition, the contents of inorganic P and organic P are not regular with APA. By comparison, TOC shows a more significant coherence with APA, meaning that organic pollution in sediments affects APA remarkably.

  11. Ecological effects of co-culturing the sea cucumber Apostichopus japonicus with the Chinese white shrimp Fenneropenaeus chinensis in an earthen pond

    Science.gov (United States)

    Zhou, Shun; Ren, Yichao; Pearce, Christopher M.; Dong, Shuanglin; Tian, Xiangli; Gao, Qinfeng; Wang, Fang

    2017-01-01

    Using net enclosures in an earthen pond, we established three culture treatments with the sea cucumber Apostichopus japonicus and the Chinese white shrimp Fenneropenaeus chinensis: monoculture of sea cucumbers (C), monoculture of shrimp (S), and co-culture of the two species (CS). We measured levels of suspended particulate matter in the water column; total organic matter, total organic carbon, total nitrogen, and carbon/nitrogen ratios in both settling particles and the sediment; and chlorophyll a levels in the sediment. We then compared these variables between the three treatments. We also examined growth, survival, and yield of the two species in the different treatments. From June to September, the mean monthly suspended particulate matter sedimentation rates in the CS and S treatments were significantly ( Pculture were all significantly greater than those of sea cucumbers in monoculture. There were no significant differences among any of these variables for shrimp reared in the two systems. The bioturbation of the sediment and fecal production of the shrimp likely supplied natural food for the sea cucumbers. Co-culture of the two species is a viable option for increasing yield per unit area, maximizing use of the water body, and diversifying crop production.

  12. Study of the Effect of Gypsum and Rice Straw Extract on the Control of Earthy-Musty Odor in Tilapia Culture Pond

    Directory of Open Access Journals (Sweden)

    Supannee SUWANPAKDEE

    2016-07-01

    Full Text Available The effect of gypsum and rice straw extract to reduce the levels of earthy-musty odor in tilapia earthen ponds was determined. Three treatments with 3 replicates in a completely randomized design were performed as follows: T1 - control; T2 - gypsum at 200 ppm, and T3 - rice straw tannin extract at 1 ppm. The results show that rice straw tannin extract treatment in tilapia ponds was the most effective method in reducing off-flavor in pond water. The use of 200 ppm gypsum in reducing off-flavor in ponds was also more effective than the control. Both rice straw extract and gypsum-treated ponds had increased fish biomass and %FCE. These methods have potential as alternative methods for the reduction of off-flavor, as well as the control of phytoplankton, turbidity, and TSS in tilapia ponds.

  13. Cultivo y Manejo de Estanques Pesqueros de Agua Fresca (Freshwater Fish Pond Culture and Management). Appropriate Technologies for Development. Manual M-1D.

    Science.gov (United States)

    Chakroff, Marilyn; Druben, Laurel, Ed.

    This is the Spanish translation of a "how-to" manual, designed as a working and teaching tool for extension agents as they establish and/or maintain local fish pond operations. The manual presents information to facilitate technology transfer and to provide a clear guide for warm water fish pond construction and management. Major topic…

  14. Effects of tilapia (Oreochromis niloticus L.) stocking and artificial feeding on water quality and production in rohu-common carp bi-culture ponds

    NARCIS (Netherlands)

    Rahman, M.M.; Verdegem, M.C.J.; Wahab, M.A.

    2008-01-01

    Previous research showed that stocking 1.5 rohu (Labeo rohita) and 0.5 common carp (Cyprinus carpio) m¿2 yields the highest production in small holder ponds in Bangladesh. The present study looked into the effects of additional stocking of Nile tilapia (Oreochromis nilotica) in fed or non-fed ponds

  15. Anaerobic alkane biodegradation by cultures enriched from oil sands tailings ponds involves multiple species capable of fumarate addition.

    Science.gov (United States)

    Tan, BoonFei; Semple, Kathleen; Foght, Julia

    2015-05-01

    A methanogenic short-chain alkane-degrading culture (SCADC) was enriched from oil sands tailings and transferred several times with a mixture of C6, C7, C8 and C10 n-alkanes as the predominant organic carbon source, plus 2-methylpentane, 3-methylpentane and methylcyclopentane as minor components. Cultures produced ∼40% of the maximum theoretical methane during 18 months incubation while depleting the n-alkanes, 2-methylpentane and methylcyclopentane. Substrate depletion correlated with detection of metabolites characteristic of fumarate activation of 2-methylpentane and methylcyclopentane, but not n-alkane metabolites. During active methanogenesis with the mixed alkanes, reverse-transcription PCR confirmed the expression of functional genes (assA and bssA) associated with hydrocarbon addition to fumarate. Pyrosequencing of 16S rRNA genes amplified during active alkane degradation revealed enrichment of Clostridia (particularly Peptococcaceae) and methanogenic Archaea (Methanosaetaceae and Methanomicrobiaceae). Methanogenic cultures transferred into medium containing sulphate produced sulphide, depleted n-alkanes and produced the corresponding succinylated alkane metabolites, but were slow to degrade 2-methylpentane and methylcyclopentane; these cultures were enriched in Deltaproteobacteria rather than Clostridia. 3-Methylpentane was not degraded by any cultures. Thus, nominally methanogenic oil sands tailings harbour dynamic and versatile hydrocarbon-degrading fermentative syntrophs and sulphate reducers capable of degrading n-, iso- and cyclo-alkanes by addition to fumarate.

  16. Growth of the purple dye murex, Bolinus brandaris (Gastropoda: Muricidae, marked and released in a semi-intensive fish culture earthen pond

    Directory of Open Access Journals (Sweden)

    Paulo Vasconcelos

    2011-11-01

    Full Text Available The present study reports the growth rate of the purple dye murex, Bolinus brandaris (Gastropoda: Muricidae, estimated from mark-recapture experiments. A total of 1067 specimens (shell length = 43.4±8.1 mm, range = 14.6−78.4 mm were marked with Dymo® tape tags and released in a semi-intensive fish culture earthen pond. After a period at liberty ranging from almost two months to around two years, 288 individuals were recaptured (shell length = 67.4±6.2 mm, range = 45.3−88.6 mm, which corresponded to a recapture rate of 27.0%. At recapture, only one specimen had lost the tag (tag loss rate < 0.1% and all remaining tags were intact and legible. Mean monthly growth rates were 0.9±1.0 mm in shell length, 0.4±0.5 mm in shell width and 0.7±0.7 g in total weight. Growth rates showed high inter-individual variability and an evident decreasing trend with specimen size. Comparison of growth rates with similar information available for other muricids confirmed that B. brandaris is a relatively slow-growing species. This provides valuable information for both fisheries management and for assessing the potential of B. brandaris as a candidate species for molluscan aquaculture.

  17. Effect of electron beam on in vitro cultured orchid organs

    Energy Technology Data Exchange (ETDEWEB)

    Ryu, Jaihyunk; Bae, Seho; Bae, Changhyu [Sunchon National Univ., Suncheon (Korea, Republic of); Kang, Hyun Suk; Lee, Byung Cheol [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2010-07-01

    Ionizing radiations have been effective mutagen sources to overcome the limitation of the useful genetic resources in natural environment. The study was conducted to investigate an effect of electron beam on organogenesis, growth patterns and genetic variation in the irradiated orchid organs. The in utero cultured rhizomes of orchids were irradiated with the electron beam in the dose range of 15Gy to 2240Gy under the condition of various beam energy and beam current. Significant decreases in survival, growth and organogenesis were observed by increase of intensity of electron beam irradiation. The irradiation intensity of lethal dose 50 of the in utero cultured orchid was estimated as approximately 500Gy to 1000Gy under 10MeV/n, and 1000Gy was optimal for growth and organogenesis of the cultures under 10MeV/n with 0.05mA treatment, and 15Gy {approx} 48Gy under 2MeV/n and 0.5mA electron beam condition. RAPD and ISSR analyses for the electron beam irradiated organs were performed to analyze genetic variation under the electron beam condition. Both of RAPD and ISSR analyses showed higher polymorphic rate in the electron-beam irradiated C. gangrene and C. Kaner.

  18. Greenhouse gas emissions ofMegalobrama amblycephala culture pond ecosystems during sun drying of pond%团头鲂池塘养殖生态系统晒塘阶段温室气体排放通量分析

    Institute of Scientific and Technical Information of China (English)

    朱林; 朱浩; 车轩; 刘晃; 刘兴国; 时旭; 杨家朋; 王小冬; 顾兆俊; 程果锋

    2016-01-01

    为探讨团头鲂池塘养殖生态系统晒塘阶段温室气体的排放规律及综合增温潜势,采用静态暗箱——气相色谱法对团头鲂池塘养殖生态系统晒塘阶段温室气体(CO2,CH4,N2O)的排放进行原位测定。结果显示,团头鲂池塘养殖生态系统晒塘阶段均表现为CO2,CH4和N2O的排放源,其中CO2排放通量达(86.72±12.46) g/m2,CH4排放量达(2.01±0.34) g/m2,N2O排放量达(7.44±0.98) mg/m2;在100 a的时间尺度上,团头鲂池塘养殖生态系统在晒塘阶段综合增温潜势为(157.28±24.31) g/m2,团头鲂池塘养殖生态系统温室气体减排空间较大。%Global warming and ozone depletion caused by greenhouse gases are currently two major global environmental issues. While China's freshwater aquaculture production has long been ranked first in the world, greenhouse gas emissions from freshwater ponds becomes an important source of China's greenhouse gas emissions. But the research on greenhouse gas emission in freshwater aquaculture ecosystem is limited. In order to investigate greenhouse gas emissions and comprehensive global warming potential ofMegalobrama amblycephala culture pond ecosystems during pond basked, we used the static opaque chamber-GC techniques to conduct anin situ determination of greenhouse gas emissions (CO2, CH4, N2O) of Megalobrama amblycephala culture pond ecosystems. The results showed that the CO2 fluxes measured in every 15 days were (2652.46±325.36), (2313.82±245.14), (1456.42±124.67) and (1373.27±167.39) mg/(m2·d) respectively for the air temperature of 8.9, 7.2, 5.8 and 6℃, at the ponds during sampling. The potential of hydrogen at the ponds during the sampling at each temperature was (7.73±0.26), (8.26±0.35), (7.75±0.37) and (7.68±0.48), respectively. The total organic carbon at the ponds for each sampling was (3.61±0.43), (3.32±0.17), (3.16±0.31) and (3.23±0.27), respectively. The redox potential for each sampling was

  19. Environmental Effects and Structural Optimization of Crab Culture in Ponds in Reclamation Zones of Gucheng Lake%固城湖围垦区池塘河蟹养殖环境影响及模式优化研究

    Institute of Scientific and Technical Information of China (English)

    周露洪; 谷孝鸿; 曾庆飞; 毛志刚; 高华梅

    2013-01-01

    为了解固城湖围垦区不同池塘的河蟹养殖环境效应并筛选出适宜的生态养殖模式,对河蟹养殖周期内不同养殖池塘的养殖情况和水环境进行跟踪研究,并构建模型估算养殖容量.结果表明,养殖周期内现有养殖模式的池塘和取水河道水质大多为GB 3838-2002《地表水环境质量标准》中的Ⅳ类和Ⅴ类水,明显劣于固城湖水质(Ⅲ类水),其中最主要的污染因子为TN和TP;池塘的浮游植物、浮游动物和底栖动物的群落结构简单,优势种分别为隐藻、秀体溞及环棱螺,且浮游动物Margalef丰富度指数与河蟹养殖产出呈显著正相关(P<0.05);基于现有养殖模式,河蟹的最大养殖容量为9855只hm-2.综合考虑养殖池塘环境、经济效益及养殖容量等因素,认为固城湖围垦区池塘河蟹的适宜生态养殖模式为:蟹苗投放密度(9000±750)只·hm-2;饵料系数0.47 ~0.53;水草覆盖度约70%(其中苦草40%,伊乐藻20%,轮叶黑藻10%);螺类投放量6 000 ~7500 kg·hm-2.%In order to study environmental effects of crab culture in different ponds in reclamation zones of the Gucheng Lake and screen an optimal ecological pattern of crab culturing, the operation of crab culture and variation of the water environment during the period were monitored and a model was constructed to estimate the carrying capacity of the ponds. Results show that under the current pattern of crab culturing, the waters in the ponds and the water supplying rivers fell in Grade Ⅳ and Ⅴ of the "Standard for Surface Water Environmental Quality" (GB 3838 -2002), and were obviously lower than that in the Gucheng Lake, which was in Grade Ⅲ. In the former, total nitrogen(TN) and total phosphorus(TP) were the main polluting factors. In the ponds, the community structures of phytoplankton, zooplankton and benthos were simple, and dominated mainly by Cryptorrwnas ehrenberg, Diapharwsoma and Bellamya. The Margalef species

  20. White Spot Syndrome Virus vulnerability of Tiger shrimp (Penaeus monodon cultured in the coastal ponds of Cox’s Bazar region, Bangladesh

    Directory of Open Access Journals (Sweden)

    Mohammad M. Monwar

    2013-07-01

    Full Text Available Jumbo tiger prawn, Penaeus monodon is the world’s most popular cultivable species for itsfast growth, hardy nature, delicious taste and market demand. During the last three decades shrimpculture has been expanded rapidly. White spot Syndrome Virus (WSSV is a great treat to this cultureexpansion. In this research, WSSV free fries were stocked in four coastal ponds with different salinities.The stocking density was kept low and constant. Water parameters, fish growth, and WSSVcontamination were recorded fortnightly. The WSSV contamination was primarily detected by using EnbioShrimp Virus Detection Test Kit, ‘Shrimple’ and further confirmed by the PCR test. Among the ponds,Pond A, B, and C were in completely controlled environmental condition where as pond D was traditionalone that exposed to tidal variations. Physico-chemical parameter varied from as, temperature 29 to32ºC, salinity 0 to 31‰, water pH 7.1 to 8.3, dissolved oxygen 3.8 to 6.3 mL L-1, alkalinity 80-122 mg L-1,ammonia 0 to 1.5 mg L-1 and transparency 23 to 50 cm. The WSSV was found positive in the pond D justafter hundred days, when the average weight of the shrimps was 26.69 g. It is observed that rapidchange in the salinity and temperature, poor environmental conditions and uncontrolled exchange ofwater made the shrimp more vulnerable to the WSSV.

  1. Electron microscopy methods in studies of cultural heritage sites

    Science.gov (United States)

    Vasiliev, A. L.; Kovalchuk, M. V.; Yatsishina, E. B.

    2016-11-01

    The history of the development and application of scanning electron microscopy (SEM), transmission electron microscopy (TEM), and energy-dispersive X-ray microanalysis (EDXMA) in studies of cultural heritage sites is considered. In fact, investigations based on these methods began when electron microscopes became a commercial product. Currently, these methods, being developed and improved, help solve many historical enigmas. To date, electron microscopy combined with microanalysis makes it possible to investigate any object, from parchment and wooden articles to pigments, tools, and objects of art. Studies by these methods have revealed that some articles were made by ancient masters using ancient "nanotechnologies"; hence, their comprehensive analysis calls for the latest achievements in the corresponding instrumental methods and sample preparation techniques.

  2. Big Fish in Little Ponds Aspire More: Mediation and Cross-Cultural Generalizability of School-Average Ability Effects on Self-Concept and Career Aspirations in Science

    Science.gov (United States)

    Nagengast, Benjamin; Marsh, Herbert W.

    2012-01-01

    Being schooled with other high-achieving peers has a detrimental influence on students' self-perceptions: School-average and class-average achievement have a negative effect on academic self-concept and career aspirations--the big-fish-little-pond effect. Individual achievement, on the other hand, predicts academic self-concept and career…

  3. Selective School Systems and Academic Self-Concept: How Explicit and Implicit School-Level Tracking Relate to the Big-Fish--Little-Pond Effect across Cultures

    Science.gov (United States)

    Salchegger, Silvia

    2016-01-01

    A large body of research has demonstrated a big-fish--little-pond effect (BFLPE) by showing that equally able students have lower academic self-concepts in high-ability schools than in low-ability schools. Although the BFLPE generalizes across many countries, it varies significantly between countries. The reasons for this variation are still…

  4. Solar ponds: a selected bibliography

    Energy Technology Data Exchange (ETDEWEB)

    1981-11-01

    This bibliography contains citations on: regular solar ponds; shallow solar ponds; and patents. Certain references are specifically recommended. The data bases searched for the bibliography are listed. (LEW)

  5. Relationship between white spot syndrome virus (WSSV) loads and characterizations of water quality in Litopenaeus vannamei culture ponds during the tropical storm

    Science.gov (United States)

    Zhang, J. S.; Li, Z. J.; Wen, G. L.; Wang, Y. L.; Luo, L.; Zhang, H. J.; Dong, H. B.

    2016-01-01

    An in-situ experiment was conducted to investigate the effect of tropical storm on the white spot syndrome virus (WSSV) loads in Litopenaeus vannamei rearing ponds. White spot syndrome virus loads, heterotrophic bacteria, Vibrio and water quality (including temperature, dissolved oxygen (DO), salinity, pH, NH4-N, and NO2-N) were continually monitored through one tropical storm. The WSSV loads decreased when tropical storm made landfall, and substantially increased when typhoon passed. The variation of WSSV loads was correlated with DO, temperature, heterotrophic bacteria count, and ammonia-N concentrations. These results suggested that maintaining high level DO and promoting heterotrophic bacteria growth in the shrimp ponds might prevent the diseases’ outbreak after the landfall of tropical storm. PMID:27822254

  6. Social relationships in an electronic environment. Cultural factors and variables

    Directory of Open Access Journals (Sweden)

    Carmine CLEMENTE

    2015-06-01

    Full Text Available Within certain cultural and social limits, some behaviours linked to the use of new technology, gaming, physical exercise or work are useful practices with a positive social value for both individuals and society. As these practices are commonly and socially accepted, the trend is to underestimate the risks and not to perceive them as deviances even when they start to be compulsive. This paper focuses on the concept of new non-substance addictions and on how some social factors influence, on the one side, this new interaction between man and technology and, on the other side, social relationships in the electronic environment.

  7. 水泥池养殖条件下虎斑乌贼的生长特性%Growth Characteristics of Sepia pharaonis under Pond-culture

    Institute of Scientific and Technical Information of China (English)

    蒋霞敏; 罗江; 彭瑞冰; 唐锋; 高晓兰; 乐可鑫; 孙志鹏

    2014-01-01

    以体重、胴长、墨囊重和壳重4个指标变化情况,研究了水泥池养殖条件下虎斑乌贼(Sepia pharaonis)的生长特性.结果表明:体重呈指数增长,日均增重量(0.09~2.78 g)不断增加,瞬时增重率(11.86%~1.03%)呈下降趋势;胴长呈直线增长,日均增长量(0.03~0.13 cm)不断波动,瞬时增长率(4.99%~0.35%)呈下降趋势;墨囊重呈指数增长,日均增重量(0.01~0.09 g)呈上升趋势,瞬时增重率(11.95%~1.68%)呈下降趋势,墨囊指数3.06%~4.25%;壳重呈指数增长,日均增重量(0.01~0.13 g)呈上升趋势,瞬时增重率(10.73%~1.02%)呈下降趋势,壳指数为5.06%~7.65%.成活率在日龄0~45 d (90.69%~95.25%)和60~150 d (95.73%~98.89%)时平稳上升,而在日龄45~60 d(饵料转变过程中)下降至最低(50.01%).体重和胴长、墨囊重、壳重之间均具有显著相关性.%The growth characteristics of Sepia pharaonis under pond-culture are studied by observing the change of weight (W), mantle length (ML), weight of the Ink-sac (WIS), and weight of the Cuttle-bone (WCB). The results show that the W grows exponentially, the average daily weight gain (0.09-2.78 g) follows an upward trend, and the instantaneous growth rate (11.86%-1.03%) shows a downward trend. The ML grows linearly, the average daily length gain (0.03-0.13 cm) fluctuate constantly, and the instantaneous growth rate (4.99%-0.35%) is found with a downward trend. In comparison, the WIS also increases exponentially, the average daily weight gain (0.01-0.09 g) presents an upward trend, the instantaneous growth rate (11.95%-1.68%) indicates a downward trend, and the ink-sac index is 3.06%-4.25%. Finally, the WCB grows sharply, the average daily weight gain (0.01-0.13 g) also manifests an upward trend, the instantaneous growth rate (10.73%-1.02%) also follows a downward trend, the cuttle-bone index is 5.06%-7.65%. It is found that the survival rate increases steadily ranging 90.69%-95.25%within the age

  8. Evaluation of the preservation value and location of farm ponds in Yunlin County, Taiwan.

    Science.gov (United States)

    Chou, Wen-Wen; Lee, Soen-Han; Wu, Chen-Fa

    2013-12-31

    Farm ponds in Yunlin County first appeared in 1,622 and have played roles in habitation, production, the ecology, culture, and disaster reduction. Farm ponds largely disappeared with the development of urban areas and the industrial sector; thus, effective preservation of the remaining ponds is critical. The criteria to evaluate the preservation value of farm ponds is established by expert questionnaires which follow the Fuzzy Delphi Method (FDM) and Fuzzy Analytic Hierarchy Process (FAHP), and GIS, which are integrated into a spatial analysis of the remaining 481 farm ponds in Yunlin County. The results show that 28 ponds should be preserved to continue the cultural interaction between farm ponds and settlements; 36 ponds should preserved to connect coasts and streams, which are important habitats for birds; 30 ponds should be preserved to increase storage capacity, recharge groundwater, and reduce land subsidence; four ponds should be preserved as Feng-Shui ponds in front of temples in settlements or as recreation areas for local citizens; and four farms should be preserved (high priority) in agricultural production areas to support irrigation. In short, FAHP and GIS are integrated to evaluate the number and locations of farm ponds that provide water for habitation, production, the ecology, culture, and disaster reduction and maintain the overall preservation value in Yunlin County. The results could inform governmental departments when considering conservation policies.

  9. Evaluation of the Preservation Value and Location of Farm Ponds in Yunlin County, Taiwan

    Directory of Open Access Journals (Sweden)

    Wen-Wen Chou

    2013-12-01

    Full Text Available Farm ponds in Yunlin County first appeared in 1,622 and have played roles in habitation, production, the ecology, culture, and disaster reduction. Farm ponds largely disappeared with the development of urban areas and the industrial sector; thus, effective preservation of the remaining ponds is critical. The criteria to evaluate the preservation value of farm ponds is established by expert questionnaires which follow the Fuzzy Delphi Method (FDM and Fuzzy Analytic Hierarchy Process (FAHP, and GIS, which are integrated into a spatial analysis of the remaining 481 farm ponds in Yunlin County. The results show that 28 ponds should be preserved to continue the cultural interaction between farm ponds and settlements; 36 ponds should preserved to connect coasts and streams, which are important habitats for birds; 30 ponds should be preserved to increase storage capacity, recharge groundwater, and reduce land subsidence; four ponds should be preserved as Feng-Shui ponds in front of temples in settlements or as recreation areas for local citizens; and four farms should be preserved (high priority in agricultural production areas to support irrigation. In short, FAHP and GIS are integrated to evaluate the number and locations of farm ponds that provide water for habitation, production, the ecology, culture, and disaster reduction and maintain the overall preservation value in Yunlin County. The results could inform governmental departments when considering conservation policies.

  10. INDUCTION OF GONADAL MATURATION OF POND CULTURED MALE TIGER SHRIMP, Penaeus monodon WITH DIFFERENT DOSAGES OF GONADOTROPIN RELEASING HORMONE ANALOGUE AGAINST EYE STALK ABLATION

    Directory of Open Access Journals (Sweden)

    Asda Laining

    2016-12-01

    Full Text Available Very low naturally mating rate of pond-reared tiger shrimp broodstock is probably due to the slow maturation of the male stock. The aim of this study was to evaluate the salmon gonadotrophin releasing hormone analoque (sGnRHa in stimulating the gonadal maturation of male stock of pond-reared tiger shrimp. The treatments were three dosages of sGnRHa at 0.1 (OV-1, 0.2 (OV-2, and 0.3 (OV-3 mL/kg of shrimp weight and control was eye stalk ablation (AB. The sGnRHa was administered via injection three times with one week interval. Male stocks with average initial body weight of 82.1 g were randomly distributed into four of 10 m3 concrete tanks, 26 males for each tank. Variables observed were performances of spermatophores and profiles of amino acid and fatty acid of muscle of the male stocks. After induction, number of male maturing indicated by spermatophores releasing from terminal ampullas was higher in shrimp induced with OV-1 (80.8% compared to control which was only 46.1%. Furthermore, shrimp treated OV-2 had the highest spermatophore weight of 0.16 g compared to control (0.11 g and other two groups. Amino acid profiles improved as the dose of sGnRHa increased up to 0.2 mL/kg from 61.23% for ablated male becoming 71.27% for OV-2. Total fatty acid also tended to improve by increasing the dose of hormone injection, however, the ablated male had higher total fatty acid content than that of OV-1. The present finding demonstrated that the dose of sGnRHa to stimulate the gonadal maturation of pond-reared male tiger shrimp could be applied at range between 0.1-0.2 mL/kg of shrimp weight.

  11. Population dynamics of Piscicola Geometra (Hirudinea:Rhynchobdellida) on Oreochromis Niloticus (Cichlidae) cultured in a rainforest fish pond, South Eastern Nigeria

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The distribution, abundance and intensity of the annelidworm, Piscicola geometra(leeches) infecting Oreochromis niloticuscultured in a rainforest fish pond, South Eastern Nigeria wasstudied over a 12 months period. Three hundred fish were examinedof which 48.3% were infected. Infection occurred throughout theyear, with a peak in February. Female fish had a significantlyhigher intensity of infection(P<0.05) than males. There was aclear seasonal periodicity in the degree of infection and thedistribution of the parasite exhibited an aggregated or contagiousmodel of dispersion. There was a significant positive correlationbetween the size of the fish and worm burden.

  12. Analysis of Phytoplankton Community Composition in Culturing Pond of Litopenaeus vannamei%凡纳滨对虾养殖水体中浮游植物群落的组成分析

    Institute of Scientific and Technical Information of China (English)

    李由明; 黄翔鹄; 李晓梅

    2012-01-01

    为了解凡纳滨对虾(Litopenaeus vannamei)池塘水体中浮游植物群落的组成及变化,本文对凡纳滨对虾养殖水体中浮游植物进行了分析.结果表明,养殖水体中的藻类共由21个种类组成,属于5大门类.浮游植物优势种群分别为绿藻门的小球藻(Chlorella sp)和波吉卵囊藻(Oocystis borgei),硅藻门的小环藻(Cyclostella sp.)、新月拟菱形藻(N.closterium sp.)、角毛藻(C.mueeleri sp.),蓝藻门的平裂藻(Merismopediasp.)和席藻(Phormidium sp.).在养殖早期和后期,浮游植物数量的变动范围分别为:0.5~2×107个/升和0.3~5×107个/升.%Phytoplankton community were analysed for the composition and variation of phytoplankton commu- nity of culturing pond of Litopenaeus vannamei in this paper. The results indicated that there were 21 species, be- longing to 5 Phylums in culturing pond. Dominant species of phytoplankton were Chlorella sp ,Oocystis, belonging to Chlorophyta and Cyclostella sp. ,N. closterium sp. ,C. mueeleri sp. , belonging to Bacillariophyta and Phormidium sp. ,Merismopedia sp. , belonging to Cyanophyta. In initial and final stage of culturing, the amount of phyto- plankton was 0.5 -2 × 107individuals/litre and 0.3 -5 × 107indiveduals/litre respectively.

  13. Walden Pond, Massachusetts: Environmental Setting and Current Investigations

    Science.gov (United States)

    Colman, John A.; Waldron, Marcus C.

    1998-01-01

    Introduction Walden Pond, in Concord, Massachusetts, is famous among lakes because of its unique social history. Walden was the setting for American naturalist Henry David Thoreau's well-known essay 'Walden; or, Life in the Woods,' first published in 1854. Thoreau lived and wrote at Walden Pond from July 1845 to September 1847. In 'Walden,' Thoreau combined highly admired writing on Transcendental philosophy with pioneering observations of aquatic ecology and physical aspects of limnology, the study of lakes. Because Thoreau also defended so effectively the value of living close to nature in the Walden woods, the pond is considered by many to be the birthplace of the American conservation movement. Visitors come from all over the world to the pond, which has been designated a National Historic Landmark, and its fame has resulted in a major fund drive to preserve the surrounding woods. Walden Pond has no surfacewater inflow or outflow, and much of its ground-water contributing area likely is preserved within the Walden Pond Reservation area (fig. 1). Only 15 miles from Boston, the pond is unusually clear and pristine for an urban-area lake. However, point sources of nutrients near the pond, and a large annual visitor attendance, concentrated during the summer when the swimming beach (fig. 2) is open, may contribute a nutrient load sufficient to change the pond environment. The occurrence of nuisance algal species, a recent beach closing, and an awareness of water-quality problems suffered by other ponds in the region raise concerns about the risk of ecological change at Walden Pond. Despite the role of Walden Pond as a cultural and environmental icon, little is known about the pond's ecological features, such as its internal nutrient cycling or the structure of its food web, nor have consistent measurements been made to determine whether these features are changing or are stable. Production rates of aquatic plants in lakes and ponds naturally undergo a slow increase

  14. No evidence for intercohort cannibalism in mixed-size cultures of food-size and fingerling hybrid catfish (channel catfish x blue catfish) grown in ponds in winter or summer.

    Science.gov (United States)

    Hybrid catfish (' Channel Catfish Ictalurus punctatus X ' Blue Catfish I. furcatus) are normally harvested by seining single-batch pond production systems in fall or winter. Ponds are typically restocked without draining. There is concern that without completely draining the pond after harvest, food...

  15. Electron microscopy, tissue culture,and immunology of ovarian carcinoma.

    Science.gov (United States)

    Ioachim, H L; Dorsett, B H; Sabbath, M; Barber, H R

    1975-10-01

    The ultrastructure of the major histologic types of ovarian carcinoma was investigated as part of a multilateral study of this tumor. The nuclear and nucleolar changes in size, shape, and structure correlated well with the degree of malignancy and tumor grading. Cytoplasmic organelles and intercellular junctions were abundant and fairly well differentiated even in ovarian carcinomas of higher grade and stage. Active processes of synthesis and secretion taking place in most of these tumors were suggested by the presence of a richly granulated endoplasmic reticulum, dilated cisternae, and numerous secretory granules. Seventy-eight different ovarian carcinomas of all histologic types were cultured in vitro for periods of up to 300 days, and their morphology in light and electron microscopy was compared to that of the original tumors. The cultures displayed a consistent pattern of growth which led to the conclusion that ovarian cancer cells in vitro preserve their salient features and are representative of the tumors of origin. Heterologous antisera raised with pooled extracts of various types of ovarian carcinomas reacted specifically in immunodiffusion and immunofluorescence tests only with ovarian carcinomas and not with normal ovaries, benigh ovarian tumors, and nonovarian malignant neoplasms, indicating the presence of a cross-reacting specific antigen for ovarian carcinomas. In other studies, autologous antibodies were isolated from antigen-antibody complexes recovered from peritoneal effusions of patients with ovarian carcinomas. These antibodies displayed a high degree of specificity against ovarian carcinoma cells when tested in immunofluorescence assays.

  16. Enhancing Ecoefficiency in Shrimp Farming through Interconnected Ponds

    Directory of Open Access Journals (Sweden)

    Ramón Héctor Barraza-Guardado

    2015-01-01

    Full Text Available The future development of shrimp farming needs to improve its ecoefficiency. The purpose of this study was to evaluate water quality, flows, and nitrogen balance and production parameters on a farm with interconnected pond design to improve the efficiency of the semi-intensive culture of Litopenaeus vannamei ponds. The study was conducted in 21 commercial culture ponds during 180 days at densities of 30–35 ind m−2 and daily water exchange <2%. Our study provides evidence that by interconnecting ponds nutrient recycling is favored by promoting the growth of primary producers of the pond as chlorophyll a. Based on the mass balance and flow of nutrients this culture system reduces the flow of solid, particulate organic matter, and nitrogen compounds to the environment and significantly increases the efficiency of water (5 to 6.5 m3 kg−1 cycle−1, when compared with traditional culture systems. With this culture system it is possible to recover up to 34% of the total nitrogen entering the system, with production in excess of 4,000 kg ha−1 shrimp. We believe that the production system with interconnected ponds is a technically feasible model to improve ecoefficiency production of shrimp farming.

  17. Studies of community structure and seasonal dynamics of planktonic copepods in saline-alkaline ponds

    Institute of Scientific and Technical Information of China (English)

    ZHAO Wen; DONG Shuanglin

    2005-01-01

    Species abundance and seasonal succession of copepods in aline-alkaline ponds were studied in Zhaodian Fish Farm, Gaoqing County, Shandong Province, from 5 April 1997 to 1 September 1998. The results indicated that in the conditions of salinity ranging from 1.36 to 20 g/L, total alkalinity changing from 2.4 to 7.2 mmol/L and pH 8-9, zooplankton in saline-alkaline ponds was composed of freshwater salt-tolerated species or halophile species, some of which are halobiont species and usually occurs in freshwater In our study, copepods were predominant in many fish-culture ponds and all control ponds without fishes in spring, late autumn and early winter Dominant species of copepods were Sinocalanus tenellus, Cyclops vicinus, Thermocyclops taihokuensis. The biomass of copepods in the control ponds without fishes was higher than that of the fish-culture ponds. ponds.

  18. Effect of BdeUovibrio bacteriovorus on Water Quality of Pond Culture%噬菌蛭弧菌对池塘养殖水质的影响

    Institute of Scientific and Technical Information of China (English)

    熊英; 苏春分; 王扬; 陈泽昌; 田树魁; 龙斌

    2012-01-01

    The experiment aimed to study the effect of BdeUovibrio bacteriovorus on water quality of pond cuhure.Bdellovibrio bacteriovorus was poured into the four major Chinese carps and carp and auratus mixed cultivation pond,and the changes of the water quality parameter such as water temperature ,pH value, H2S content ,NH3-N and NO2-N content ,and the death numbers of fish were studied.It was demonstrated that the main water quality indexes of the ponds could be remarkably improved by the use of Bdellovibrio bacteriovorus.It also helped to accelerate the reduction of the content of NH3-N and NO2-N in the aquaculture water.The NH3-N and NO2-N content in the experimenta groups were dramatically lower than those in the control groups (P〈0.01), but the changes of H2S and pH value were not obvious (p〉0.05).On the aspects of preventing against fish disease,the use of Bdellovibrio bacteriovorus helped to effectively prevent the red skin disease,gill disease and enteritis of grass carp.The incidence and mortality rate of grass carp were also reduced.%为了探讨噬菌蛭弧菌(Bdellovibrio bacteriovorus)在池塘养殖生产中的效果,向大宗淡水鱼类混养池泼洒噬菌蛭弧菌,观察养殖池养殖水体的水温、pH值、NH3-N、亚硝酸盐、硫化氢等主要水质指标的变化及鱼的死亡情况。结果表明:蛭弧菌制剂对养殖水体的主要水化指标具有明显的改善作用,试验塘的NH3-N、亚硝酸盐值极显著低于对照塘(p〈0.01),而试验塘与对照塘的硫化氢、pH值差异不显著(P〉0.05)。在鱼病预防方面,蛭弧菌制剂使用后,能有效预防草鱼的赤皮、烂鳃和肠炎病,草鱼的发病率、死亡率明显下降。

  19. Kealia Pond - Ungulate Exclusion Fence

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This project will contribute to the building of a fence around the Kealia Pond National Wildlife Refuge. Kealia Pond NWR is home to two endangered waterbird species,...

  20. 3D correlative light and electron microscopy of cultured cells using serial blockface scanning electron microscopy

    Science.gov (United States)

    Lerner, Thomas R.; Burden, Jemima J.; Nkwe, David O.; Pelchen-Matthews, Annegret; Domart, Marie-Charlotte; Durgan, Joanne; Weston, Anne; Jones, Martin L.; Peddie, Christopher J.; Carzaniga, Raffaella; Florey, Oliver; Marsh, Mark; Gutierrez, Maximiliano G.

    2017-01-01

    ABSTRACT The processes of life take place in multiple dimensions, but imaging these processes in even three dimensions is challenging. Here, we describe a workflow for 3D correlative light and electron microscopy (CLEM) of cell monolayers using fluorescence microscopy to identify and follow biological events, combined with serial blockface scanning electron microscopy to analyse the underlying ultrastructure. The workflow encompasses all steps from cell culture to sample processing, imaging strategy, and 3D image processing and analysis. We demonstrate successful application of the workflow to three studies, each aiming to better understand complex and dynamic biological processes, including bacterial and viral infections of cultured cells and formation of entotic cell-in-cell structures commonly observed in tumours. Our workflow revealed new insight into the replicative niche of Mycobacterium tuberculosis in primary human lymphatic endothelial cells, HIV-1 in human monocyte-derived macrophages, and the composition of the entotic vacuole. The broad application of this 3D CLEM technique will make it a useful addition to the correlative imaging toolbox for biomedical research. PMID:27445312

  1. 3D correlative light and electron microscopy of cultured cells using serial blockface scanning electron microscopy.

    Science.gov (United States)

    Russell, Matthew R G; Lerner, Thomas R; Burden, Jemima J; Nkwe, David O; Pelchen-Matthews, Annegret; Domart, Marie-Charlotte; Durgan, Joanne; Weston, Anne; Jones, Martin L; Peddie, Christopher J; Carzaniga, Raffaella; Florey, Oliver; Marsh, Mark; Gutierrez, Maximiliano G; Collinson, Lucy M

    2017-01-01

    The processes of life take place in multiple dimensions, but imaging these processes in even three dimensions is challenging. Here, we describe a workflow for 3D correlative light and electron microscopy (CLEM) of cell monolayers using fluorescence microscopy to identify and follow biological events, combined with serial blockface scanning electron microscopy to analyse the underlying ultrastructure. The workflow encompasses all steps from cell culture to sample processing, imaging strategy, and 3D image processing and analysis. We demonstrate successful application of the workflow to three studies, each aiming to better understand complex and dynamic biological processes, including bacterial and viral infections of cultured cells and formation of entotic cell-in-cell structures commonly observed in tumours. Our workflow revealed new insight into the replicative niche of Mycobacterium tuberculosis in primary human lymphatic endothelial cells, HIV-1 in human monocyte-derived macrophages, and the composition of the entotic vacuole. The broad application of this 3D CLEM technique will make it a useful addition to the correlative imaging toolbox for biomedical research. © 2017. Published by The Company of Biologists Ltd.

  2. Expanding the Diet for DIET: Electron Donors Supporting Direct Interspecies Electron Transfer (DIET in Defined Co-Cultures

    Directory of Open Access Journals (Sweden)

    Li-YIng eWang

    2016-03-01

    Full Text Available Direct interspecies electron transfer (DIET has been recognized as an alternative to interspecies H2 transfer as a mechanism for syntrophic growth, but previous studies on DIET with defined co-cultures have only documented DIET with ethanol as the electron donor in the absence of conductive materials. Co-cultures of Geobacter metallireducens and Geobacter sulfurreducens metabolized propanol, butanol, propionate, and butyrate with the reduction of fumarate to succinate. G. metallireducens utilized each of these substrates whereas only electrons available from DIET supported G. sulfurreducens respiration. A co-culture of G. metallireducens and a strain of G. sulfurreducens that could not metabolize acetate oxidized acetate with fumarate as the electron acceptor, demonstrating that acetate can also be syntrophically metabolized via DIET. A co-culture of G. metallireducens and Methanosaeta harundinacea previously shown to syntrophically convert ethanol to methane via DIET metabolized propanol or butanol as the sole electron donor, but not propionate or butyrate. The stoichiometric accumulation of propionate or butyrate in the propanol- or butanol-fed cultures demonstrated that M. harundinaceae could conserve energy to support growth solely from electrons derived from DIET. Co-cultures of G. metallireducens and Methanosarcina barkeri could also incompletely metabolize propanol and butanol and did not metabolize propionate or butyrate as sole electron donors. These results expand the range of substrates that are known to be syntrophically metabolized through DIET, but suggest that claims of propionate and butyrate metabolism via DIET in mixed microbial communities warrant further validation.

  3. Primeval procreative comet pond.

    Science.gov (United States)

    Clark, B C

    1988-01-01

    It is speculated that life originated in a small, shallow body of water containing concentrated prebiotic organic feedstocks, inorganic compounds, and catalytic agents in a diversity of microenvironments. This pond was formed by an improbable, fortuitous soft-landing of a cometary nucleus, or fragment thereof, on the surface of a suitable planet with an atmosphere in an appropriate thermodynamic state, such as Earth.

  4. Simulation of Nile tilapia (Oreochromis niloticus niloticus L.) culture in ponds, through individual-based modelling, using a population dynamic approach

    NARCIS (Netherlands)

    Graaf, de G.J.; Dekker, P.J.; Huisman, E.A.; Verreth, J.A.J.

    2005-01-01

    A simulation model for the production of the Nile tilapia (Oreochromis niloticus niloticus L.) for mixed- or mono-sex culture and for poly-culture with the African catfish (Clarias gariepinus Burchell 1822) or African snakehead (Parachanna obscura Günther 1861) is presented. The model is based on an

  5. Some observations on the growth and cyst production characteristics of the brine shrimp Artemia sp. (Gujarat strain) in pond culture and its potential for import substitution

    OpenAIRE

    Gopalakrishnan, P.; Krishna Raju, V.; Thaker, S R

    1989-01-01

    Experimental culture of the brine shrimp Artemia sp. (Gujarat strain) and production of cyst is discussed. The qualitative and quantitative aspects of the cyst and its economic potential for import substitution are highlighted.

  6. Effects of carbohydrate source for maintaining a high C:N ratio and fish driven re-suspension on pond ecology and production in periphyton-based freshwater prawn culture systems

    NARCIS (Netherlands)

    Asaduzzaman, M.; Wahab, M.A.; Verdegem, M.C.J.; Adhikary, R.K.; Rahman, S.M.S.; Azim, M.E.; Verreth, J.A.J.

    2010-01-01

    The present research investigated the effect of carbohydrate (CH) source for maintaining a high C:N ratio, and tilapia driven bioturbation on pond ecology, production and economical performances in C/N controlled periphyton-based (C/N-CP) freshwater prawn ponds. Two carbohydrate sources (high-cost t

  7. The study of recirculating aquaculture system in pond and its purification effect

    Science.gov (United States)

    Qu, Jiangqi; Zhang, Qingjing; Jia, Chengxia; Liu, Pan; Yang, Mu

    2017-05-01

    In this paper, a recirculating aquaculture purification system (RAPS) was designed to solve the problems of aquaculture pollution and shortage of freshwater resource according to the characteristic of northern freshwater ponds of China. The system were arranged in series and composed of high density culture pond, deposit pond, floating and submerged plant pond, ecological floating bed pond and biofilm filtrate pond. At the fish density of 20~30kg/m3 in the high density culture pond, the water quality parameters were monitored seasonally. The results indicated that the removal rate of total nitrogen, total phosphorus, ammonia nitrogen and nitrite nitrogen in the recirculating aquaculture system were 69.59%, 77.89%, 72.54% and 68.68%, respectively. The floating and submerged plant pond and ecological floating bed pond can remove TN and TP obviously, and increase dissolved oxygen and transparency significantly. And the biofilm filtrate pond has good effect of removing ammonium nitrogen and nitrite nitrogen, meanwhile, the microbial communities in the recirculating aquaculture system regulate on the water quality. Therefore, the RAPS show significant effects on water saving and pollution emission reducing.

  8. Microbiology of solar salt ponds

    Science.gov (United States)

    Javor, B.

    1985-01-01

    Solar salt ponds are shallow ponds of brines that range in salinity from that of normal seawater (3.4 percent) through NaCl saturation. Some salterns evaporate brines to the potash stage of concentration (bitterns). All the brines (except the bitterns, which are devoid of life) harbor high concentrations of microorganisms. The high concentrations of microorganisms and their adaptation to life in the salt pond are discussed.

  9. 凡纳滨对虾高位池反季节健康养殖技术的研究%Study on the Technology of Off-season Healthy Aquaculture in Higher-altitude Culture Ponds of Litopenaeus Vannamei

    Institute of Scientific and Technical Information of China (English)

    黄永春; 林祥日; 蔡葆青; 尤颖哲; 郭灿

    2012-01-01

    为探讨凡纳滨对虾反季节集约化健康养殖技术.本实验在合理投饵、科学管理的基础上投放健康优质虾苗、应用微生态制剂和微管充氧等措施,结合虾池水质理化因子(D.O、透明度、pH、盐度、NH4+-N)和病原生物(弧菌、WSSV、TSV)的实时监测.结果显示:养殖期间水温、透明度、pH、盐度、溶解氧分别保持在19.5~26.7℃,平均(22.94±0.63)C;23.2~59.1 cm,平均(37.8±12.0) cm; pH 7.7~8.5,平均(8.1±0.0.2);pH酸碱度30.0%~33.5%,平均(31.72±0.84)%;4.0~6.0 mg/L,平均(5.13±0.38) mg/L;虾池氨氮控制在0.05~1.30 mg/L,平均(0.59±0.09) mg/L;池水中异养细菌和弧菌分别控制在[(5.05~19.23)×104]cfu/mL,平均[(10.92±3.45)×104]cfu/mL;[(0.45~3.71)×104]cfu/mL,平均[(1.14±0.73)×104] cfu/mL.养殖期间对虾体长生长(L)与养殖天数(d)的回归方程:L=0.087d+0.1968 (r=0.9843),体重生长(W)与养殖天数(d)的回归方程:W=0.0001d2.3847(r=0.9948).28口实验虾池中只有5口的产量低于500 kg/666.67 m2,占17.86%,其余虾池对虾产量均达到500 kg/666.67 m2以上,其中有39.29%的虾池产量达到500~1000 kg/666.67 m2; 28.57%的虾池产量1000~1250 kg/666.67 m2;10.71%的虾池产量1250~1500 kg/666.67m2; 3.57%的虾池产量1500 kg/666.67 m2以上,平均产量(769.08±440.22) kg/666.67 m2,对虾平均成活率为(67.84±15.23)%,饵料系数(1.27±0.83).%The technology of Litopenaeus vannamei in higher-altitude culture ponds by off-season healthy aquaculture was studied. In this experiment, the health quality shrimp larvae, microecology preparation and microtubule oxygenation were utilized by the scientific plan and execution of programs which the pathogens and the environment-related factors were monitored by real-time. The results showed that the water temperature, transparency, pH, salinity and dissolved oxygen were kept in 19.5-26.7℃(mean 22.94±0.63℃), 23.2-59.1 cm(mean 37.8± 12.0cm), 7

  10. Ecological evaluation of two prawn culture fields in the Cochin Backwater based on premonsoon diurnal observations

    Digital Repository Service at National Institute of Oceanography (India)

    Balasubramanian, T.; Viswakumar, M.; Venugopal, P.

    Extensive low lying areas of the Cochin Backwater peripheries at its lower reaches are bunded into interconnected ponds for paddy-cum-prawn culture. Results of a study of two representative ponds are reported. The ponds under study were found...

  11. Effect of polyculture of shrimp with fish on luminous bacterial growth in grow-out pond water and sediment

    Institute of Scientific and Technical Information of China (English)

    Thangapalam Jawahar Abraham

    2014-01-01

    Objective: To study the distribution of marine luminous bacteria in shrimp culture systems of West Bengal and the effect of polyculture of shrimp with fish to reduce luminous bacteria. Methods: Luminous bacterial counts were enumerated by spread plating on seawater complex agar from shrimp grow-out pond water and pond sediment samples of West Bengal, India. Results: About 31.16%and 51.44%of pond sediment and pond water samples respectively had detectable levels of luminous bacteria. It was noticed that in normal ponds a shift happened in bacterial profile of water from the day of flooding up to 60 d, with the dominance of luminous bacteria among vibrios, reaching counts 104 cells/mL or more. While in diseased ponds, luminous bacterial abundance within the ponds was noticed in the first 6 weeks of culture. Marked reduction in luminous bacterial counts of water and sediment was observed through out the culture period in polyculture ponds compared to monoculture ponds. There was no incidence of white spot syndrome viral disease and luminous vibriosis in both controlled and experimental ponds. Conclusions:The results suggest vigilant monitoring of ponds for luminous bacteria abundance and polyculture of shrimp with fish in ecofriendly sustainable aquaculture can reduce the impact of shrimp disease outbreak.

  12. Effects of “submerged aeration systems” on water quality and phytoplankton community structure in Portunus trituberculatus culture ponds%“底充式增氧”技术对梭子蟹养殖池塘水质环境及浮游植物群落结构的影响

    Institute of Scientific and Technical Information of China (English)

    傅彩萍; 郑忠明; 金忠文; 郝锵; 陆开宏

    2012-01-01

    于2009年6-9月在浙江省宁海县三门湾海域养殖场,选取2口水文环境相似的梭子蟹Portunus trituberculatus养殖池塘,分别采用“底充式增氧”(实验塘)和传统水车式增氧(对照塘)方式,比较研究了池塘水质环境及其浮游植物群落结构的变化.结果显示:(1)实验塘水质的溶解氧和氨氮指标均优于对照塘,其中实验塘底部溶解氧质量浓度维持在5 mg/L以上,而对照塘则维持在4.28~6.45mg/L;养殖末期,实验塘的氨氮质量浓度为0.140mg/L,低于对照塘(1.360mg/L).(2)实验塘内主要藻类细胞丰度值(3 980×105个/L)远远高于对照塘(234×105个/L).经MDS标序、ANOSIM检验、SIMPER和Bio-Env分析可知,2口池塘浮游植物群落结构存在明显差异,养殖中后期实验塘浮游植物群落结构稳定,而对照塘的浮游植物群落结构较不稳定.实验塘优势种为卵囊藻Oocystis sp.和席藻Phormidiumsp.,对照塘以蓝藻和硅藻为优势种,2口池塘浮游植物群落结构不相似性高达84.44%.浮游植物细胞丰度与含有溶解氧的环境变量组合相关性最强.(3)与水车式增氧方式相比,“底充式增氧”技术对梭子蟹养殖塘的增氧效果明显,且能改善池塘水质,同时对于改善和稳定养殖池塘内的藻相结构起到重要作用.%Two adjacent Portunus trituberculatus culture ponds with similar hydrological environment in Sanmen Bay, Ninghai County, Zhejiang Province were selected to compare the effects of "submerged aeration system" (experimental pond) and traditional waterwheel aeration system (control pond) on water quality and phytoplankton community structure of the aquaculture pond from June to September 2009. The results show that (1) the indices of dissolved oxygen and ammonia nitrogen of the experimental pond with "submerged aeration system" are better than those of the control pond; the mass concentration of dissolved oxygen at the bottom of the experimental pond is kept at above

  13. Performance evaluation of pumping systems used in commercial-scale, split-pond aquaculture

    Science.gov (United States)

    Split-pond aquaculture systems have been adopted widely by United States catfish farmers as a way to improve production performance. The split-pond consists of a fish-culture basin that is connected to a waste-treatment lagoon by two water conveyance structures. Water is circulated between the two b...

  14. Emergency power for fish produced in intensive, pond-based systems

    Science.gov (United States)

    Power failure in a heavily stocked and fed pond-based culture system can result in massive fish losses within minutes. Even in a conventional pond with a stand-by tractor powered aerator, the shock of a sudden loss of power can dramatically affect production resulting in mortalities and reduced perf...

  15. 仿刺参养殖池塘中浮游和底栖藻类群落的变化%Variation in Phytoplankton and Benthic Alga Communities in Sea Cucumber Apostichopus japonicus Culture Ponds

    Institute of Scientific and Technical Information of China (English)

    刘冉; 迟爽; 程敬伟; 曾勇; 赵振军; 马家好; 崔龙波

    2013-01-01

    Composition ,density ,biomass ,Shannon-Weiner index ,Pielou’s evenness index ,Margalef’s richness index and McNaugton dominance index of the phytoplankton and benthic alga communities were determined in six 5000 ~ 6000 m2 ponds with depth of 1 .8 ~ 2 .0 m for sea cucumber A postichopus j aponicus culture in coastal Laizihou ,Shandong Province from October ,2011 to September ,2012 .A total of 40 species in 7 phyla of phytoplankon were found ,with the predominant Bacillariophyta ,and 18 benthic alga species in Bacillariophyta .The density was ranged from 7 .810 × 105 to 249 .662 × 105 cell/L ,with biomass of 1 .65~12 .07 mg/L in the phytoplankon and from 4 .124 × 105 to 14 .289 × 105 cell/cm2 ,with biomass of 2 .60~11 .27 mg/cm2 ,in the benthic algae in the ponds .There were Shannon-Weiner index of 2 .09~2 .93 in the phytoplankon and 1 .67~2 .73 in the benthic algae ,and Pielou’s evenness index of 0 .56~0 .78 in the phytoplankon and 0 .48~0 .73 in the benthic algae .The phytoplankon showed Margalef’s richness index from 1 .74 to 2 .42 and the benthic algae from 1 .41 to 1 .83 .The predominant phytoplankton species were found to be changed with time ,but almost no changes were observed in the predominant benthic algae in the year . There were very significant positive correlation between the density of phytoplankton and that of benthic algae in the ponds ,indicating that the species diversity in phytoplankton and benthic algae community is rich and the ecological environment is good in the culture ponds .%2011年10月至2012年9月对山东省莱州市仿刺参养殖区的6口面积为5000~6000 m2,水深1.8~2.0 m的养殖池塘中的浮游和底栖藻类进行了调查,分析其群落的组成、密度、生物量、Shannon-Weiner多样性指数、Pielou均匀度指数、Margalef丰富度指数和McNaugton优势度指数。研究结果表明,仿刺参池塘中共鉴定出浮游藻类7门40种,主要由硅藻组成;底栖藻类18种,均

  16. Estimation of Carrying Capacity of Manila Clam (Ruditapesphilippinarum) Culture Pond in Houhai Reclamation Area of Putian city,China%莆田后海垦区菲律宾蛤仔养殖池养殖容量的估算

    Institute of Scientific and Technical Information of China (English)

    杨淑芳; 张磊; 阎希柱

    2016-01-01

    From August 2013 to January 2014,the chlorophyll -a,primary productivity of phytoplankton,clams mortality rate in Houhai reclamation area of Putian were determined.The carrying capacity of the two Manila clam ponds wereestimated by Parsons TR-Takahashi M Ecological Trophodynamicsmodel [P=(BEn )×k]and Tait coastal energy flowing analysis model {B=[(0.1×C)/Q]×k}.Taking into consideration of the unused prima-ry productivity due to the pond effluent,the corrected results of two models were 5.52t and 7.10t for pond 1,with an average of 6.31t;3.60t and 4.62t for pond 2,with an average of 4.11t for two ponds.The actual yields of the two ponds accounted for 59.43%and 97.32%of the estimated capacities respectively.Two ponds of clam mortality rates were 23.43%and 22.5%,respectively.The capacity of pond 1 was significantly larger than that of pond 2.The pos-sible reasons are as follows:chl-a,the shapes of the pond,location and management.The carrying capacity of pond 2 was close to its actual yield.The estimated suitable breeding densities of Manila clam for pond 1 and for pond 2 were 0.61kg/m2 and 0.40kg/m2 respectively.As the actual breeding densities of two ponds are 0.19kg/m2 for each pond. The estimated suitable breeding density of Manila clam calculated from the carrying capacity was larger than the actu-al breeding density.A certain potential to increase the number of breeding clam exists.%2013年8月—2014年2月,对莆田后海垦区菲律宾蛤仔反季节高效生态养殖池叶绿素a、浮游植物初级生产量、蛤仔死亡率等进行了测定,采用ParsonsTR和TakahashiM营养动态模型和Tait沿岸海域能流分析模型对2个菲律宾蛤仔养殖池的养殖容量进行估算,扣除20%的日排水量导致的初级生产量损失,2种估算模型得到的养殖容量经校正后,池1为5.52t、7.1t,平均为6.31t;池2为3.60t、4.62t,平均为4.11t。两个花蛤养殖池的实际产量

  17. 不同增氧方式对精养池塘溶氧的影响%Impact of different aeration approaches on dissolved oxygen for intensive culture ponds

    Institute of Scientific and Technical Information of China (English)

    张世羊; 李谷; 陶玲; 李晓莉

    2013-01-01

      当前对于在精养池塘中如何配制和合理使用不同机械增氧方式缺乏系统的比较研究。该文为了探讨高温季节晴好天气不同机械增氧方式对池塘溶氧全天调控的影响,试验设计如下:于夏天高温季节集中对精养池塘应用3种不同增氧方式,在晴好天气的白天和夜间进行增氧效果试验。结果发现:无论增氧机开启与否,池塘的溶氧都存在明显的昼夜起伏,且在午后出现峰值。增氧机的开启增强了上下水层交换,削减了氧差,减少了上层溶氧的逸出损失,提升了下层水体的低溶氧水平。池塘上层溶氧起伏程度大于下层,下层溶氧变化滞后于上层(下层溶氧出现峰值落后于上层约2~5 h),且这种滞后性为增氧机运行所削弱。夜间增氧能向池塘补充溶氧,但仍不足以弥补鱼类和浮游生物的代谢、微生物的生长及有机物的氧化分解造成的溶氧损耗。单从机械增氧能力来看,叶轮式>微孔式>耕水机。综合分析节能和增氧效果,在精养池塘养殖环境下,白天开机增氧选择耕水机较为合适,而夜间应急增氧选择叶轮式更可取。试验通过对不同机械增氧方式增氧效果和能耗的系统比较,为合理选择和使用增氧方式提供了一定的参考价值。%Aerators are essential in semi-intensive and intensive aquaculture to maintain an environment congenial to the physiological requirements of the cultured organisms. In an intensive aquaculture, the full oxygen demand of the cultured species cannot be met through natural aeration only. Therefore, artificial aeration is essential. In past years, various types of aerators have been developed to maintain the desired concentration of dissolved oxygen (DO) in the pond water to improve the energy efficiency of the oxygen mass-transfer process. In the present study, it is intended to compare the dynamical efficiency and economic

  18. Use of {gamma}-hexachlorocyclohexane as a terminal electron acceptor by an anaerobic enrichment culture

    Energy Technology Data Exchange (ETDEWEB)

    Elango, Vijai, E-mail: velango@g.clemson.edu [Hazardous Substance Research Center/South and Southwest, Louisiana State University, 3221 Patrick Taylor Hall, Baton Rouge, LA 70803 (United States); Kurtz, Harry D. [Department of Genetics and Biochemistry, Clemson University, 100 Jordan Hall, Clemson, SC 29634 (United States); Anderson, Christina; Freedman, David L. [Department of Environmental Engineering and Earth Sciences, Box 340919, Clemson University, Clemson, SC 29634-0919 (United States)

    2011-12-15

    Highlights: Black-Right-Pointing-Pointer Use of {gamma}-hexachlorocyclohexane as a terminal electron acceptor was demonstrated. Black-Right-Pointing-Pointer H{sub 2} served as the electron donor for an enrichment culture that dechlorinated {gamma}-HCH. Black-Right-Pointing-Pointer H{sub 2} consumption for acetogenesis and methanogenesis stopped in HEPES media. Black-Right-Pointing-Pointer Addition of vancomycin significantly slowed the rate of {gamma}-HCH dechlorination. Black-Right-Pointing-Pointer Previously identified chlororespiring microbes were not detected in the enrichment. - Abstract: The use of {gamma}-hexachlorocyclohexane (HCH) as a terminal electron acceptor via organohalide respiration was demonstrated for the first time with an enrichment culture grown in a sulfate-free HEPES-buffered anaerobic mineral salts medium. The enrichment culture was initially developed with soil and groundwater from an industrial site contaminated with HCH isomers, chlorinated benzenes, and chlorinated ethenes. When hydrogen served as the electron donor, 79-90% of the electron equivalents from hydrogen were used by the enrichment culture for reductive dechlorination of the {gamma}-HCH, which was provided at a saturation concentration of approximately 10 mg/L. Benzene and chlorobenzene were the only volatile transformation products detected, accounting for 25% and 75% of the {gamma}-HCH consumed (on a molar basis), respectively. The enrichment culture remained active with only hydrogen as the electron donor and {gamma}-HCH as the electron acceptor through several transfers to fresh mineral salts medium for more than one year. Addition of vancomycin to the culture significantly slowed the rate of {gamma}-HCH dechlorination, suggesting that a Gram-positive organism is responsible for the reduction of {gamma}-HCH. Analysis of the {gamma}-HCH dechlorinating enrichment culture did not detect any known chlororespiring genera, including Dehalobacter. In bicarbonate-buffered medium

  19. ELECTRON MICROSCOPE EVIDENCE OF VIRUS INFECTION IN CULTURED MARINE FISH

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Electron microscope investigation on the red sea bream (Pagrosomus major), bastard halibut (Paralichthys olivaceus) and stone flounder (Kareius bicoloratus) in North China revealed virus infection in the bodies of the dead and diseased fish. These viruses included the lymphocystis disease virus (LDV), parvovirus, globular virus, and a kind of baculavirus which was not discovered and reported before and is now tentatively named baculavirus of stone flounder (Kareius bicoloratus).

  20. [Effects of probiotics on Penaeus vannamei pond sediments].

    Science.gov (United States)

    Wang, Yanbo; Zha, Longying; Xu, Zirong

    2006-09-01

    This paper studied the effects of probiotics on the sediment of Penaeus vannamei pond during 117 days of culture period. The results showed that probiotics application significantly decreased the concentrations of total nitrogen, total phosphorous, and sulfide in sediment, but no significant difference was observed in total plate count (TPC) of microbes between treated and control ponds. The final average presumptive vibrio count (PVC) of treated pond sediment (3.65 x 10(3) cfu x g(-1)) was significantly lower than that of the control (1.16 x 10(5) cfu x g(-1)), while the average number of BS (Bacillus), AB (ammonifying bacteria), PSOB (presumptive sulphur oxidizing bacteria) and SRB (sulphur reducing bacteria) in treated pond sediment was higher than that of the control. These data showed that probiotics could decrease the nutrients (nitrogen, phosphate and sulfur) accumulation and improve the composition of bacterial populations in pond sediment, and thus, supply a good sediment environment for the healthily culture of the shrimp.

  1. Use of artificial substrate in pond culture of freshwater prawn (Macrobrachium rosenbergii: a new approach regarding growth performance and economic return

    Directory of Open Access Journals (Sweden)

    Dilshad Milky Tuly

    2014-04-01

    Full Text Available An experiment was conducted for six months to evaluate the effects of artificial substrates on the survival, growth and production of Macrobrachium rosenbergii juveniles. The treatment T1 contained locally available bamboo-made substrate both vertical and horizontal and treatment T2 received no substrate. Juvenile prawns (0.40±0.13 g were stocked at the rate of 19,760 prawns ha-1. The water quality parameters range such as temperature, pH and DO were 22.06-33.45°C, 7.70-8.40 and 4.75-6.15 mgl-1 respectively which was no significant difference (P0.05 than T2 (56.87%. The specific growth rate, food conversion ratio and protein efficiency ratio were 1.19 % and 1.14 %, 3.15 and 4.39, 0.98 and 0.71 in T1 and T2 respectively which were not significantly different (P0.05 than T2. Thus growth and survival of prawn juveniles improved in presence of artificial substrate which could be economically viable technique for the freshwater prawn culture.

  2. Impact of Population and Latrines on Fecal Contamination of Ponds in Rural Bangladesh

    Science.gov (United States)

    Knappett, Peter S. K.; Escamilla, Veronica; Layton, Alice; McKay, Larry D.; Emch, Michael; Williams, Daniel E.; Huq, Md. R.; Alam, Md. J.; Farhana, Labony; Mailloux, Brian J.; Ferguson, Andy; Sayler, Gary S.; Ahmed, Kazi M.; van Geen, Alexander

    2011-01-01

    A majority of households in Bangladesh rely on pond water for hygiene. Exposure to pond water fecal contamination could therefore still contribute to diarrheal disease despite the installation of numerous tubewells for drinking. The objectives of this study are to determine the predominant sources (human or livestock) of fecal pollution in ponds and examine the association between local population, latrine density, latrine quality and concentrations of fecal bacteria and pathogens in pond water. Forty-three ponds were analyzed for E. coli using culture-based methods and E. coli, Bacteroidales and adenovirus using quantitative PCR. Population and sanitation spatial data were collected and measured against pond fecal contamination. Humans were the dominant source of fecal contamination in 79% of the ponds according to Bacteroidales measurements. Ponds directly receiving latrine effluent had the highest concentrations of fecal indicator bacteria (up to 106 Most Probable Number (MPN) of culturable E. coli per 100 mL). Concentrations of fecal indicator bacteria correlated with population surveyed within a distance of 30-70 m (p<0.05) and total latrines surveyed within 50-70 m (p<0.05). Unsanitary latrines (visible effluent or open pits) within the pond drainage basin were also significantly correlated to fecal indicator concentrations (p<0.05). Water in the vast majority of the surveyed ponds contained unsafe levels of fecal contamination attributable primarily to unsanitary latrines, and to lesser extent to sanitary latrines and cattle. Since the majority of fecal pollution is derived from human waste, continued use of pond water could help explain the persistence of diarrheal disease in rural South Asia. PMID:21632095

  3. Induction of retrovirus particles in human testicular tumor (Tera-1) cell cultures: an electron microscopic study.

    Science.gov (United States)

    Bronson, D L; Fraley, E E; Fogh, J; Kalter, S S

    1979-08-01

    The Tera-1 and Tera-2 cell lines, established from germ-cell tumors of the human testis, were examined by electron microscopy for particles with the morphology of retroviruses. Extracellular and budding particles were observed at low frequencies only in cultures of Tera-1 cells that had been treated with 5-iodo-2'-deoxyuridine and dexamethasone. No particles were detected in untreated cultures of Tera-1 cells or in any preparations of Tera-2 cells.

  4. The Role of Perceived Substitution and Individual Culture in the Adoption of Electronic Newspapers in Scandinavia

    DEFF Research Database (Denmark)

    Pogrebnyakov, Nicolai; Buchmann, Mikael

    2014-01-01

    Introduction:This paper explores the factors behind the adoption of electronic newspapers. Adoption is hypothesized to be driven by attributes of the electronic newspaper artefact (expressed by perceived substitution) and individual cultural characteristics of potential adopters. Perceived...... substitution is seen as a factor that influences the displacement of printed newspapers with electronic ones. Method: Data were collected using Web surveys and consist of 1804 responses from a representative sample of individuals in Denmark, Norway and Sweden. Analysis: Partial least squares path modelling...... was used to test hypotheses. Results: The results indicate that perceived substitution explains the adoption of electronic newspapers well, while most cultural factors did not show a significant effect on adoption. Conclusion: These results add to research on how perceived substitutive functionality of one...

  5. Design and Application of a Solar Mobile Pond Aquaculture Water Quality-Regulation Machine Based in Bream Pond Aquaculture.

    Directory of Open Access Journals (Sweden)

    Xingguo Liu

    Full Text Available Bream pond aquaculture plays a very important role in China's aquaculture industry and is the main source of aquatic products. To regulate and control pond water quality and sediment, a movable solar pond aquaculture water quality regulation machine (SMWM was designed and used. This machine is solar-powered and moves on water, and its primary components are a solar power supply device, a sediment lifting device, a mechanism for walking on the water's surface and a control system. The solar power supply device provides power for the machine, and the water walking mechanism drives the machine's motion on the water. The sediment lifting device orbits the main section of the machine and affects a large area of the pond. Tests of the machine's mechanical properties revealed that the minimum illumination necessary for the SMWM to function is 13,000 Lx and that its stable speed on the water is 0.02-0.03 m/s. For an illumination of 13,000-52,500 Lx, the sediment lifting device runs at 0.13-0.35 m/s, and its water delivery capacity is 110-208 m(3/h. The sediment lifting device is able to fold away, and the angle of the suction chamber can be adjusted, making the machine work well in ponds at different water depths from 0.5 m to 2 m. The optimal distance from the sediment lifting device to the bottom of the pond is 10-15 cm. In addition, adjusting the length of the connecting rod and the direction of the traction rope allows the SMWM to work in a pond water area greater than 80%. The analysis of water quality in Wuchang bream (Parabramis pekinensis and silver carp (Hypophthalmichthys molitrix culture ponds using the SMWM resulted in decreased NH3(+-N and available phosphorus concentrations and increased TP concentrations. The TN content and the amount of available phosphorus in the sediment were reduced. In addition, the fish production showed that the SMWM enhanced the yields of Wuchang bream and silver carp by more than 30% and 24%, respectively. These

  6. Design and Application of a Solar Mobile Pond Aquaculture Water Quality-Regulation Machine Based in Bream Pond Aquaculture.

    Science.gov (United States)

    Liu, Xingguo; Xu, Hao; Ma, Zhuojun; Zhang, Yongjun; Tian, Changfeng; Cheng, Guofeng; Zou, Haisheng; Lu, Shimin; Liu, Shijing; Tang, Rong

    2016-01-01

    Bream pond aquaculture plays a very important role in China's aquaculture industry and is the main source of aquatic products. To regulate and control pond water quality and sediment, a movable solar pond aquaculture water quality regulation machine (SMWM) was designed and used. This machine is solar-powered and moves on water, and its primary components are a solar power supply device, a sediment lifting device, a mechanism for walking on the water's surface and a control system. The solar power supply device provides power for the machine, and the water walking mechanism drives the machine's motion on the water. The sediment lifting device orbits the main section of the machine and affects a large area of the pond. Tests of the machine's mechanical properties revealed that the minimum illumination necessary for the SMWM to function is 13,000 Lx and that its stable speed on the water is 0.02-0.03 m/s. For an illumination of 13,000-52,500 Lx, the sediment lifting device runs at 0.13-0.35 m/s, and its water delivery capacity is 110-208 m(3)/h. The sediment lifting device is able to fold away, and the angle of the suction chamber can be adjusted, making the machine work well in ponds at different water depths from 0.5 m to 2 m. The optimal distance from the sediment lifting device to the bottom of the pond is 10-15 cm. In addition, adjusting the length of the connecting rod and the direction of the traction rope allows the SMWM to work in a pond water area greater than 80%. The analysis of water quality in Wuchang bream (Parabramis pekinensis) and silver carp (Hypophthalmichthys molitrix) culture ponds using the SMWM resulted in decreased NH3(+)-N and available phosphorus concentrations and increased TP concentrations. The TN content and the amount of available phosphorus in the sediment were reduced. In addition, the fish production showed that the SMWM enhanced the yields of Wuchang bream and silver carp by more than 30% and 24%, respectively. These results

  7. Validation of cell-free culture using scanning electron microscopy (SEM) and gene expression studies.

    Science.gov (United States)

    Yang, R; Elankumaran, Y; Hijjawi, N; Ryan, U

    2015-06-01

    A cell-free culture system for Cryptosporidium parvum was analysed using scanning electron microscopy (SEM) to characterise life cycle stages and compare gene expression in cell-free culture and cell culture using HCT-8 cells. Cryptosporidium parvum samples were harvested at 2 h, 8 h, 14 h, 26 h, 50 h, 74 h, 98 h, 122 h and 170 h, chemically fixed and specimens were observed using a Zeiss 1555 scanning electron microscope. The presence of sporozoites, trophozoites and type I merozoites were identified by SEM. Gene expression in cell culture and cell-free culture was studied using reverse transcriptase quantitative PCR (RT-qPCR) of the sporozoite surface antigen protein (cp15), the glycoprotein 900 (gp900), the Cryptosporidium oocyst wall protein (COWP) and 18S ribosomal RNA (rRNA) genes in both cell free and conventional cell culture. In cell culture, cp15 expression peaked at 74 h, gp900 expression peaked at 74 h and 98 h and COWP expression peaked at 50 h. In cell-free culture, CP15 expression peaked at 98 h, gp900 expression peaked at 74 h and COWP expression peaked at 122 h. The present study is the first to compare gene expression of C. parvum in cell culture and cell-free culture and to characterise life cycle stages of C. parvum in cell-free culture using SEM. Findings from this study showed that gene expression patterns in cell culture and cell-free culture were similar but in cell-free culture, gene expression was delayed for CP15 and COWP in cell free culture compared with the cell culture system and was lower. Although three life cycle stageswere conclusively identified, improvements in SEM methodology should lead to the detection of more life cycle stages.

  8. CULTURAL ISSUES IN WEBSITE DESIGN. A EUROPEAN PERSPECTIVE ON ELECTRONIC COMMERCE

    Directory of Open Access Journals (Sweden)

    Claudia Asimionoaei

    2009-09-01

    Full Text Available Commerce and electronic business have gained momentum in recent years. Attracted by the mirage of global markets, most companies enter the virtual environment without taking into account thecultural implications of such a step. The major question that arises at this stage of development of global trade on the Internet is if companies understand the importance of cultural factors in their actions on the global market and if we have tools, theories and models with which to carry out cultural analysis for understanding cultural environments online.

  9. Adjusting effect of jet flotation machine on water quality in Litopenaeus vannamei culturing pond%气浮机对高位池养虾水质的调控效果

    Institute of Scientific and Technical Information of China (English)

    朱林; 车轩; 刘晃; 管崇武; 田昌凤

    2014-01-01

    An important factor inLitopenaeus vannameiculturing process is water quality, whose stability for shrimp pond has close relationship to the community structure of microplankton. How to control water color is the key toLitopenaeus vannamei breeding, especially to the controlling of the species and amount of microplankton, The dominant species accounted for 49%~99% of the total in most cases, and the amount of microplankton depends on the amount of dominant species. To explore a new biological control system, environment control technology based on the jet flotation machine inLitopenaeus vannameiculturing process was studied in this paper. TwoLitopenaeus vannameiculturing ponds with the same 667 m2, in which we put the same number of shrimp seed at the same time, were used, one for biological control test, the other for contrast. The new biological control system, in which we added a loopback for the water treatment, was composed of a 7.5-kilowatt motor, a 7.5-kilowatt water pump and a 1.5-kilowatt jet flotation machine. The jet flotation machine, which ran 24 hours a day during experiment, was placed in a glass fiber reinforced plastically (size: 2 m×1.5 m×1 m). The level of ammonia nitrogen and nitrate nitrogen was tested by sodium hypobromous acid oxidation and diazo-azo at 9:00 am, while the species and amount of microplankton were recorded by a nikon AZ100 microscope at 14:00 pm. The dissolved oxygen, temperature, potential of hydrogen and salinity of two ponds were measured by YSI ProODO and YSI Proplus three times a day regularly. Number of vibrio was recorded every day. The length and weight of shrimps were measured by electronic balance and vernier caliper every 20 days. Experimental group and control group were labelled as A and B groups, respectively. Research results showed that there was no significant difference in the potential of hydrogen between A and B groups based on the same amount of feeding, and the potentials of hydrogen of the two groups did

  10. Scanning electron microscopy of the nail plate in onychomycosis patients with negative fungal culture.

    Science.gov (United States)

    Yue, Xueping; Li, Qing; Wang, Hongwei; Sun, Yilin; Wang, Aiping; Zhang, Qi; Zhang, Cuiping

    2016-01-01

    Onychomycosis is a common dermatological problem and can be identified by direct microscopic examination and fungal culture. However, the positive rate of fungal culture is low. This study investigated the application of scanning electron microscopy in the diagnosis of onychomycosis in 20 patients with negative fungal culture. In this study, a routine glutaraldehyde fixation method was used to prepare specimens for electron microscope examination. Results showed that under the scanning electron microscope, significant structural damage was observed in the nail plate in all patients. Hyphaes were seen in 70% of cases. A mixture of scattered hyphaes, pseudohyphaes, and spores was observed in 30% of cases. A mixture of spores and bacteria was observed in 10% of cases. A mixture of hyphaes and bacteria was observed in 20% of cases. The typical hyphae pierced a thin layer or single layer of corneocytes. Hyphaes could be smooth, sleek, and straight with visible separation, or dry, bent, and folded with a smooth surface. The diameter of hyphaes was 1-2 µm. The scattered spores were the main form of spore growth, and the growth of budding spores can be seen attached to the surface of layered armor. Most of the bacteria were gathered in clumps on the ventral surface, especially in grooves. In conclusion, scanning electron microscopy can be used to preliminarily identify the pathogen involved and the degree of damage in cases where onychomycosis is clinically diagnosed, but fungal culture is negative.

  11. Molecular diversity of the ammonia-oxidizing bacteria community in disused tin-mining ponds located within Kampar, Perak, Malaysia.

    Science.gov (United States)

    Sow, S L S; Khoo, G; Chong, L K; Smith, T J; Harrison, P L; Ong, H K A

    2014-02-01

    Disused tin-mining ponds make up a significant amount of water bodies in Malaysia particularly at the Kinta Valley in the state of Perak where tin-mining activities were the most extensive, and these abundantly available water sources are widely used in the field of aquaculture and agriculture. However, the natural ecology and physicochemical conditions of these ponds, many of which have been altered due to secondary post-mining activities, remains to be explored. As ammonia-oxidizing bacteria (AOB) are directly related to the nutrient cycles of aquatic environments and are useful bioindicators of environmental variations, the focus of this study was to identify AOBs associated with disused tin-mining ponds that have a history of different secondary activities in comparison to ponds which were left untouched and remained as part of the landscape. The 16S rDNA gene was used to detect AOBs in the sediment and water sampled from the three types of disused mining ponds, namely ponds without secondary activity, ponds that were used for lotus cultivation and post-aquaculture ponds. When the varying pond types were compared with the sequence and phylogenetic analysis of the AOB clone libraries, both Nitrosomonas and Nitrosospira-like AOB were detected though Nitrosospira spp. was seen to be the most ubiquitous AOB as it was present in all ponds types. However, AOBs were not detected in the sediments of idle ponds. Based on rarefaction analysis and diversity indices, the disused mining pond with lotus culture indicated the highest richness of AOBs. Canonical correspondence analysis indicated that among the physicochemical properties of the pond sites, TAN and nitrite were shown to be the main factors that influenced the community structure of AOBs in these disused tin-mining ponds.

  12. 216-B-3 expansion ponds closure plan

    Energy Technology Data Exchange (ETDEWEB)

    1994-10-01

    This document describes the activities for clean closure under the Resource Conservation and Recovery Act of 1976 (RCRA) of the 216-B-3 Expansion Ponds. The 216-B-3 Expansion Ponds are operated by the US Department of Energy, Richland Operations Office (DOE-RL) and co-operated by Westinghouse Hanford Company (Westinghouse Hanford). The 216-B-3 Expansion Ponds consists of a series of three earthen, unlined, interconnected ponds that receive waste water from various 200 East Area operating facilities. The 3A, 3B, and 3C ponds are referred to as Expansion Ponds because they expanded the capability of the B Pond System. Waste water (primarily cooling water, steam condensate, and sanitary water) from various 200 East Area facilities is discharged to the Bypass pipe (Project X-009). Water discharged to the Bypass pipe flows directly into the 216-B-3C Pond. The ponds were operated in a cascade mode, where the Main Pond overflowed into the 3A Pond and the 3A Pond overflowed into the 3C Pond. The 3B Pond has not received waste water since May 1985; however, when in operation, the 3B Pond received overflow from the 3A Pond. In the past, waste water discharges to the Expansion Ponds had the potential to have contained mixed waste (radioactive waste and dangerous waste). The radioactive portion of mixed waste has been interpreted by the US Department of Energy (DOE) to be regulated under the Atomic Energy Act of 1954; the dangerous waste portion of mixed waste is regulated under RCRA.

  13. 农业生态系统文化服务的支付意愿与受偿意愿的差异性分析——以上海池塘养殖为例%Difference between the WTP and WTA in cultural service value evaluation of agriculture ecosystems: Shanghai pond aquaculture case study

    Institute of Scientific and Technical Information of China (English)

    范晓赟; 杨正勇; 唐克勇; 杨怀宇

    2012-01-01

    Pond aquaculture has existed in China for thousands of years and has been not only a major source of food, but also provided cultural service. The development of service industry in agriculture has further highlighted the value of pond aquaculture. The Contingent Valuation Method (CVM), one of several methods for evaluating non-market values, has been widely used data analysis. However, there has remained much controversy on the effectiveness and stability of CVM. One such hot spot of discussion has been strategic bias, a significant disparity between willingness to pay (WTP) and willingness to accept (WTA), in evaluation of environment products and services values. Current literature has shown that few researches exist on the evaluation of cultural service values of aquaculture ecosystems. This paper used pond aquaculture in Qingpu, Jiading and Fengxian Districts of Shanghai to evaluate the cultural services values and discuss the difference between WTP and WTA as given by Tobit and Mulit-Logit models. The results showed that WTP was affected by the income, education, interest and satisfaction with pond environments of the interviewees. A significant positive relationship existed between WTP and the above factors. WTA was also influenced by incomeand satisfaction with pond environments. WTA was significantly positively related to income. But satisfaction with pond environment was negatively related to both WTP and WTA. Household income, register, age and interest in pond activities of interviewee were the main influence factors on WTA/WTP asymmetry. The average WTA/WTP ratio was 5 : 1. Income, substitution, endowment and prospect effects as well as property right affected the differences between WTP and WTA. Due to deviations in interviewees' understandings of WTA, responses were higher than the real pond value. Based on this fact, WTP was used as the preferred assessment method. The average value of WTP of the investigated area was 163.75 Yuan per person. Then

  14. A comparison of Nannochloropsis salina growth performance in two outdoor pond designs: conventional raceways versus the ARID pond with superior temperature management

    Energy Technology Data Exchange (ETDEWEB)

    Crowe, Braden J.; Attalah, Said; Agrawal, Shweta; Waller, Peter; Ryan, Randy; Van Wagenen, Jonathan M.; Chavis, Aaron R.; Kyndt, John; Kacira, Murat; Ogden, Kimberly L.; Huesemann, Michael H.

    2012-10-01

    The present study examines how climatic conditions and pond design affect the growth performance of microalgae. From January to April of 2011, outdoor batch cultures of Nannochloropsis salina were grown in three replicate 780 L conventional raceways, as well as in an experimental 7500 L ARID (Algae Raceway Integrated Design) pond. The ARID culture system utilizes a series of 8 to 20 cm deep basins and a 1.5 m deep canal to enhance light exposure and mitigate temperature variations and extremes. The ARID culture reached the stationary phase 27 days earlier than the conventional raceways, which can be attributed to its superior temperature management and shallower basins. On a night when the air temperature dropped to -9 °C, the water temperature was 18 °C higher in the ARID pond than in the conventional raceways. Lipid and fatty acid content ranged from 16 - 25 % and 5 - 15 %, respectively, as a percentage of AFDW. Palmitic, palmitoleic, and eicosapentaenoic acid comprised the majority of fatty acids. While the ARID culture system achieved nearly double the volumetric productivity relative to the conventional raceways (0.023 vs 0.013 g L-1day-1), areal biomass productivities were of similar magnitude in both pond systems (3.34 vs. 3.47 g m-2day-1), suggesting that the ARID pond design has to be further optimized, most likely by increasing the culture depth or operating at higher cell densities while maintaining adequate mixing.

  15. Effects of C/N ratio and substrate addition on natural food communities in freshwater prawn monoculture ponds

    NARCIS (Netherlands)

    Asaduzzaman, M.; Rahman, M.M.; Azim, M.E.; Islam, M.A.; Wahab, M.A.; Verdegem, M.C.J.; Verreth, J.A.J.

    2010-01-01

    An on-station trial was conducted to investigate the effects of three C/N ratios (10/1, 15/1 and 20/1) along with substrate presence or absence on natural food communities in freshwater prawn culture ponds. An experiment was carried out in 40 m2 ponds stocked with a stocking density of 2 prawn juven

  16. Strategy of Quality Improvement of Pond Shrimp Post Harvest Management (Penaeus monodon Fabricius in Mahakam Delta (Case Study

    Directory of Open Access Journals (Sweden)

    Andi Noor Asikin

    2012-10-01

    Full Text Available Mahakam Delta area, which is situated in Kutai Kartanegara Regency, has become a pond center that gives a significant contribution to shrimp export of East Kalimantan Province. Pond-produced shrimps, however, do not always accord to the intention of cold storage companies at expected price. The companies even sometimes reject the request due to poor quality of the product. The decreasing shrimp quality may be due to maintenance process by the pond farmers as well as the improper collectors. In the other hand, importing countries have decided more and more restricted requirements for the imported fishing products. This study was held in Muara Jawa, Anggana, and Muara Badak Districts using techniques of data collection of in-depth interview with twelve respondents. In order to improve shrimp quality, farmers or the producers have to formulate a strategy towards the improvement of the post harvest shrimps from the pond using an Analytical Hierarchy Process (AHP. Results of the AHP consist of as follows: (1 application of pond shrimp post harvest technology and improvement of facilities and accommodation that support the quality improvement of the pond shrimps, (2 human resource quality improvement of pond farmers, collectors, and field instructors, (3 development of pond culture by applying best practices principle and local policies in order to improve the quality of the pond shrimps, and (4 improvement of interagency coordination, monitoring, and evaluation to enhance the pond shrimp quality

  17. Par Pond Fish, Water, and Sediment Chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Paller, M.H. [Westinghouse Savannah River Company, AIKEN, SC (United States); Wike, L.D.

    1996-06-01

    The objectives of this report are to describe the Par Pond fish community and the impact of the drawdown and refill on the community, describe contaminant levels in Par Pond fish, sediments, and water and indicate how contaminant concentrations and distributions were affected by the drawdown and refill, and predict possible effects of future water level fluctuations in Par Pond.

  18. Carbon sequestration in the soils of aquaculture ponds, crop land, and forest land in southern Ohio, USA.

    Science.gov (United States)

    Adhikari, Subhendu; Lal, Rattan; Wang, Han-Ping

    2014-03-01

    Soil samples were collected from four aquaculture ponds (yellow perch culture), a control pond (without aquaculture activities, fallow pond), crop land (under corn), and forest land to estimate the carbon (C) sequestration potential in the Piketon county, Ohio, USA. The averaged total of C was 6.5 ± 2, 8.8 ± 2, 8.53 ± 0.2 and 10.49 ± 1.1 Mg/ha (Mg=10(6)g) in  2.5mm), for aquaculture ponds, control ponds, cropland and forest land, respectively. The soil/sediment C pool followed the order of forest > crop land soils > aquaculture pond soils.

  19. Effects of season on ecological processes in extensive earthen tilapia ponds in Southeastern Brazil.

    Science.gov (United States)

    Favaro, E G P; Sipaúba-Tavares, L H; Milstein, A

    2015-11-01

    In Southeastern Brazil tilapia culture is conducted in extensive and semi-intensive flow-through earthen ponds, being water availability and flow management different in the rainy and dry seasons. In this region lettuce wastes are a potential cheap input for tilapia culture. This study examined the ecological processes developing during the rainy and dry seasons in three extensive flow-through earthen tilapia ponds fertilized with lettuce wastes. Water quality, plankton and sediment parameters were sampled monthly during a year. Factor analysis was used to identify the ecological processes occurring within the ponds and to construct a conceptual graphic model of the pond ecosystem functioning during the rainy and dry seasons. Processes related to nitrogen cycling presented differences between both seasons while processes related to phosphorus cycling did not. Ecological differences among ponds were due to effects of wind protection by surrounding vegetation, organic loading entering, tilapia density and its grazing pressure on zooplankton. Differences in tilapia growth among ponds were related to stocking density and ecological process affecting tilapia food availability and intraspecific competition. Lettuce wastes addition into the ponds did not produce negative effects, thus this practice may be considered a disposal option and a low-cost input source for tilapia, at least at the amounts applied in this study.

  20. 论鱼塘建构对文化生态的支撑功能——基于对贵州黄岗侗族社区的思考%On the Supportive Functions of Fish Ponds to Cultural Ecology:A Study Based on the Survey of the Dong Community of Huanggang in Guizhou

    Institute of Scientific and Technical Information of China (English)

    杨曾辉; 李银艳; 彭书佳

    2012-01-01

    在侗族传统村寨的整个结构当中,鱼塘扮演着极为关键的角色。人为建构起来的鱼塘次生生态系统之所以能够获得侗族乡民的喜爱,原因是多方面的。一方面,鱼塘自身存在着诸多的生态调节功能,能够为侗族社区的正常运转提供力所能及的物质、能量和信息。另一方面,在侗族传统社会的建构过程当中,以及侗族传统文化与当地自然生态环境相互磨合的过程中,人工建构起来的鱼塘获得侗族传统文化的某些属性,成为了侗族传统文化生态的有机构成部分。通过田野调查表明,目前典岗的鱼塘总面积还占据着整个村寨聚落总面积的1/3以上,而再将当地乡民的回忆和相关的历史文献结合后发现,在早期村寨建构时,这里的水域面积占到了村寨聚落85%以上。在考虑到当地自然地理环境的特殊性,特别是地表崎岖不平这种特定的地貌背景之后,对形成这样大比例的固定水域,显然是出自人工的有意配置,而不是纯自然运行的产物。这样的人工配置目标则是要让鱼塘为村寨的整体建构发挥三大功能:一是对区域水循环的调控功能;二是起到"防火带"的安全护卫功能;三是带来丰厚的综合产出效益。%Fish ponds play a key role in the whole structure of Dong traditional villages. There are various reasons for Dong people’s love of the secondary eco-system of man-made fish ponds. On one hand, fish ponds, with their ecological adjustment functions, can provide materials, energies and information for the normal operation of Dong communities. On the other hand, such ponds, in the process of Dong’s traditional social construction and the mutual integration between Dong traditional culture and the local natural environment, have obtained some qualities of Dong traditional culture and have thus become an organic component of Dong’s traditional cultural ecology. The survey shows that such ponds

  1. Nitrogen Removal in Wastewater Ponds,

    Science.gov (United States)

    1984-06-01

    by convection to the interaction between the algae and the CO,/ and radiation. Eckenfelder ’ developed the follow- alkalinity system in the pond. If...Pollu- 4. Eckenfelder , W.W. (1966) Industrial Water tion Control Federation, 54(4): 344. Pollution Control. New York: McGraw-Hill. 19. Porcella, D.B., P.H

  2. Environmental factors causing skin ulcer symdrome occurrence in pond-culturedApostichopus japonicus%池塘养殖刺参腐皮综合征发病环境因素分析

    Institute of Scientific and Technical Information of China (English)

    费聿涛; 李秋芬; 张艳; 成钰; 李莉; 王晓红

    2016-01-01

    The relationships between skin ulcer symdrome occurrence in the sea cucumber,Apostichopus japonicus, and environmental factors were analyzed by comparing the environmental indices in ponds containing diseased and non-diseased sea cucumber in two communities of Shaogezhuang (SGZ) and Suliu (SL) in Hongdao, Qingdao, Shandong Province. Between July 23, before any disease occurred, and August 11, we detected 4 cultivable bacte-rial groups (heterotrophic bacteria, vibrios, nitrifying bacteria, and sulfurring bacteria) and measured 7 physi-cal-chemical indices (temperature, pH, salinity, dissolved oxygen, inorganic nitrogen, and chemical oxygen de-mand) in the pond water and detected 6 bacterial groups (heterotrophic bacteria, vibrios, nitrifying bacteria, sul-phuring bacteria, sulphurate-reducing bacteria, nitrate-reducing bacteria) and measured four physical-chemical indices (pH, redox potential, content of sulfide, and organic carbon) in the pond sediments. The number of bacte-rial groups in the diseased pond SGZ-1# did not differ significantly from those in the non-diseased pond SGZ-2# on the day that disease occurred, whereas the temperature was higher (25.94℃) and the salinity was lower (24.47). Furthermore, concentration of the nitrite (79.56 µg/L) in pond water and the sulfide (221.1 mg/g) in the sediment were higher in the diseased pond SGZ-1#, exceeding the tolerance thresholds of the sea cucumber. The number of vibrio species in the diseased pond SL-S2# of the Suliu community was significantly higher (1.85×104 CFU/mL) than that in the non-diseased pond SL-N2# on the day that disease occurred, and was also higher than the number in the diseased pond SGZ-1# in the Shaogezhuang community. The physical-chemical indices in pond SL-S2# was much better than those in pond SL-N2#. Therefore, we infer that the disease that occurred in the sea cucumbers in Shaogezhuang was closely related to the large sudden changes in the physical-chemical indices of the water and

  3. Oxidation pond for municipal wastewater treatment

    Science.gov (United States)

    Butler, Erick; Hung, Yung-Tse; Suleiman Al Ahmad, Mohammed; Yeh, Ruth Yu-Li; Liu, Robert Lian-Huey; Fu, Yen-Pei

    2017-03-01

    This literature review examines process, design, and cost issues related to using oxidation ponds for wastewater treatment. Many of the topics have applications at either full scale or in isolation for laboratory analysis. Oxidation ponds have many advantages. The oxidation pond treatment process is natural, because it uses microorganisms such as bacteria and algae. This makes the method of treatment cost-effective in terms of its construction, maintenance, and energy requirements. Oxidation ponds are also productive, because it generates effluent that can be used for other applications. Finally, oxidation ponds can be considered a sustainable method for treatment of wastewater.

  4. 凡纳滨对虾设施养殖池塘浮游生物群落结构及多样性研究%Community structure and biodiversity of plankton in Litopenaeus vannamei culture pond

    Institute of Scientific and Technical Information of China (English)

    何京; 陈晨; 王一农; 钟硕楠; 刘静; 林志华

    2015-01-01

    The species, quantity changes and biodiversity on the culture pond of Litopenaeus vannamei were studied . The results showed that the total number of species of phytoplankton were 40, out of which the Bacillariophyta takes up 27 species;the Chlo-rophyta had 7 species;and the Cyanophyta had 4 species;the Xanthophyta had one specie and Pyrrophyta had one specie. The total number of species of zooplankton were 17, out of which the Protozoa had 8 species;the Rotifers had 6 species;the Cladocerans had 3 species. The population density of phytoplankton was 4.4×104-6.3×102 mg/mL, the biomass was 12.6-882.0 mg/L, the Shannon-Wie-ner index was 0-3.17, the Margalef richness index was 0.56-0.95, the Pielou evenness index was 0.19-0.90. The population density of zooplankton was 12.6mg/L-1~882.0 mg/mL, method the biomass was 1.2×102-2.7×102 mg/L.The species number and the density were little than those in the sea. In the same cultivation, there are big different in the species and density of plankton.%研究了后期凡纳滨对虾设施养殖29个池塘中浮游生物的种类组成、数量差异及种类多样性。结果表明:共鉴定出浮游植物5门25属40种,浮游动物3门14属17种,未鉴定种类8种。其中硅藻门27种,绿藻门7种,蓝藻门4种,黄藻门1种,甲藻门1种;原生动物门8种,轮虫类6种,枝角类3种。29个池塘浮游植物丰度6.3×102~4.4×104 cell/mL,生物量12.6~882.0 mg/L,Shannon-Wiener多样性指数0~3.17,Margalef丰富度指数范围0.56~0.95,Pielou均匀度0.19~0.90;浮游动物丰度12.6 mg/L~882.0 mg/mL,生物量1.2×102~2.7×102 mg/L。凡纳滨对虾养殖池塘中,浮游生物种类相对自然海区少、密度大。在相同管理模式下,池塘中浮游生物种类和数量有较大差异,多样性指数也有较大差异。

  5. Algae/bacteria consortium in high rate ponds : influence of solar radiation on the phytoplankton community.

    OpenAIRE

    Assemany, Paula Peixoto; Calijuri, Maria Lúcia; Couto, Eduardo de Aguiar do; Souza, Mauro Henrique Batalha de; Silva, Nirlane Cristiane; Santiago, Aníbal da Fonseca; Castro, Jackeline de Siqueira

    2015-01-01

    Using multivariate statistical tools, the composition of the phytoplankton community was related to the characteristics of the domestic sewage used as culture medium in three high rate ponds (HRPs) submitted to different solar radiation levels. A total of 32 genera of phytoplankton were identified in the ponds; the class Chlorophyceae was the most abundant during the entire sampling period, with a larger number of individuals of the genus Desmodesmus in the summer and fall, and of the genu...

  6. Physico-Chemical and Biological Parameters of the Three Rural Ponds of Sasaram of Bihar

    Directory of Open Access Journals (Sweden)

    Jyoti Choudhary

    2014-06-01

    Full Text Available Physico chemical and biological parameters of the three rural pond of Sasaram,Bihar has been studied to see the present condition for its better utilization. The study revealed that parameters are within permissible limit for fish culture and the stocking should be done as per the productivity of the water. As per the BOD estimation the ponds falls under moderately polluted category.

  7. Social Relation between Businessman and Community in Management of Intensive Shrimp Pond

    Science.gov (United States)

    Gumay Febryano, Indra; Sinurat, James; Lovinia Salampessy, Messalina

    2017-02-01

    Expansion of aquaculture, especially shrimp culture, is the primary cause of deforestation of mangrove along coastal zone. This phenomenon is pretty much related to social relation between businessman of intensive shrimp pond and community around coastal zone. The objective of this research is to explain social relation between businessman and community in managing intensive shrimp pond. This research is a kind of qualitative research and the method used is a case study. The result of this research shows that the behaviour of the majority of businessman of intensive shrimp pond is not accordingly with environmental concerns as they compelled conversion of mangrove and they disposed waste of shrimp pond into the sea. Such kind of behaviour caused degradation of water ecosystem and marginalizing local community. Corporate Social Responsibility (CSR) which was implemented by businessman of intensive shrimp pond in the area of social, religion, and education can downgrade the coming up of social turbulence. Otherwise, CSR in enabling economic community and environmental management was not conducted yet. CSR in environmental management can be conducted by businessman of intensive shrimp pond by considering the existence of mangrove and pond management and waste in a better way, so that environment around ponds is not polluted and the sustainability of shrimp pond business as well as income of community can be guaranteed. Accordingly with the result of this research, CSR is not only involving businessman of intensive shrimp pond and community, but also involving local government in terms of right and responsibility of citizen as well as management and development of community.

  8. Observations on algal populations in an experimental maturation pond system

    CSIR Research Space (South Africa)

    Shillinglaw, SN

    1977-01-01

    Full Text Available . Likewise the adults, which are carnivorous, could have had an effect on zooplankton and other animal populations in the ponds. Xrnopus laevis populations were unfortunately not monitored. Temperature There was a seasonal increase in water temperature... of efficient ammonia removal. However, this observation must be treated with extreme caution since plate count numbers depend largely upon the culture medium used. Obviously more observations using different media would seem to be in order. It is also...

  9. Efficiency of aquatic macrophytes to treat Nile tilapia pond effluents

    Directory of Open Access Journals (Sweden)

    Henry-Silva Gustavo Gonzaga

    2006-01-01

    Full Text Available The effluents from fish farming can increase the quantity of suspended solids and promote the enrichment of nitrogen and phosphorus in aquatic ecosystems. In this context, the aim of this work was to evaluate the efficiency of three species of floating aquatic macrophytes (Eichhornia crassipes, Pistia stratiotes and Salvinia molesta to treat effluents from Nile tilapia culture ponds. The effluent originated from a 1,000-m² pond stocked with 2,000 male Nile tilapia Oreochromis niloticus. The treatment systems consisted of 12 experimental tanks, three tanks for each macrophyte species, and three control tanks (without plants. Water samples were collected from the: (i fish pond source water, (ii effluent from fish pond and (iii effluents from the treatment tanks. The following water variables were evaluated: turbidity, total and dissolved nitrogen, ammoniacal-N, nitrate-N, nitrite-N, total phosphorus and dissolved phosphorus. E. crassipes and P. stratiotes were more efficient in total phosphorus removal (82.0% and 83.3%, respectively and total nitrogen removal (46.1% and 43.9%, respectively than the S. molesta (72.1% total phosphorus and 42.7% total nitrogen and the control (50.3% total phosphorus and 22.8% total nitrogen, indicating that the treated effluents may be reused in the aquaculture activity.

  10. Quantitative analyses of the bacterial microbiota of rearing environment, tilapia and common carp cultured in earthen ponds and inhibitory activity of its lactic acid bacteria on fish spoilage and pathogenic bacteria.

    Science.gov (United States)

    Kaktcham, Pierre Marie; Temgoua, Jules-Bocamdé; Ngoufack Zambou, François; Diaz-Ruiz, Gloria; Wacher, Carmen; Pérez-Chabela, María de Lourdes

    2017-02-01

    The present study aimed to evaluate the bacterial load of water, Nile Tilapia and common Carp intestines from earthen ponds, isolate lactic acid bacteria (LAB) and assess their antimicrobial activity against fish spoilage and pathogenic bacteria. Following enumeration and isolation of microorganisms the antimicrobial activity of the LAB isolates was evaluated. Taxonomic identification of selected antagonistic LAB strains was assessed, followed by partial characterisation of their antimicrobial metabolites. Results showed that high counts (>4 log c.f.u ml(-1) or 8 log c.f.u g(-1)) of total aerobic bacteria were recorded in pond waters and fish intestines. The microbiota were also found to be dominated by Salmonella spp., Vibrio spp., Staphylococcus spp. and Escherichia coli. LAB isolates (5.60%) exhibited potent direct and extracellular antimicrobial activity against the host-derived and non host-derived spoilage and pathogenic bacteria. These antagonistic isolates were identified and Lactococcus lactis subsp. lactis was found as the predominant (42.85%) specie. The strains displayed the ability to produce lactic, acetic, butyric, propionic and valeric acids. Bacteriocin-like inhibitory substances with activity against Gram-positive and Gram-negative (Vibrio spp. and Pseudomonas aeruginosa) bacteria were produced by three L. lactis subsp. lactis strains. In this study, the LAB from the microbiota of fish and pond water showed potent antimicrobial activity against fish spoilage or pathogenic bacteria from the same host or ecological niche. The studied Cameroonian aquatic niche is an ideal source of antagonistic LAB that could be appropriate as new fish biopreservatives or disease control agents in aquaculture under tropical conditions in particular or worldwide in general.

  11. Electron Microscopy Studies, Surface Analysis and Microbial Culturing Experiments on a Depth Profile Through Martian Meteorite Nakhla

    Science.gov (United States)

    Toporski, J. K. W.; Steele, A.; Westall, F.; Griffin, C.; Whitby, C.; Avci, R.; McKay, D. S.

    2000-01-01

    Combined electron microscopy studies and culturing experiments have shown that Nakhla became contaminated with recent terrestrial microorganisms. Additional surface analysis detected an as yet unknown organic species which may represent a biomarker.

  12. Electron microscopy of primary cell cultures in solution and correlative optical microscopy using ASEM

    Energy Technology Data Exchange (ETDEWEB)

    Hirano, Kazumi; Kinoshita, Takaaki [Laboratory of Cell Biology, Department of Bioinformatics, Faculty of Engineering, Soka University, 1-236 Tangi-machi, Hachioji, Tokyo 192-8577 (Japan); Uemura, Takeshi [Department of Molecular Neurobiology and Pharmacology, Graduate School of Medicine, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan); Department of Molecular and Cellular Physiology, Shinshu University School of Medicine, 3-1-1 Asahi, Matsumoto, Nagano 390-8621 (Japan); Motohashi, Hozumi [Department of Gene Expression Regulation, Institute of Development, Aging and Cancer, Tohoku University, 4-1 Seiryo-cho, Aoba-ku, Sendai 980-8575 (Japan); Watanabe, Yohei; Ebihara, Tatsuhiko [Biomedical Research Institute, National Institute of Industrial Science and Technology (AIST), 1-1-1 Higashi, Tsukuba 305-8566 (Japan); Nishiyama, Hidetoshi [JEOL Ltd., 1-2 Musashino 3-chome, Akishima, Tokyo 196-8558 (Japan); Sato, Mari [Biomedical Research Institute, National Institute of Industrial Science and Technology (AIST), 1-1-1 Higashi, Tsukuba 305-8566 (Japan); Suga, Mitsuo [JEOL Ltd., 1-2 Musashino 3-chome, Akishima, Tokyo 196-8558 (Japan); Maruyama, Yuusuke; Tsuji, Noriko M. [Biomedical Research Institute, National Institute of Industrial Science and Technology (AIST), 1-1-1 Higashi, Tsukuba 305-8566 (Japan); Yamamoto, Masayuki [Department of Medical Biochemistry, Tohoku University Graduate School of Medicine, 2-1 Seiryo-cho, Aoba-ku, Sendai 980-8575 (Japan); Nishihara, Shoko, E-mail: shoko@soka.ac.jp [Laboratory of Cell Biology, Department of Bioinformatics, Faculty of Engineering, Soka University, 1-236 Tangi-machi, Hachioji, Tokyo 192-8577 (Japan); Sato, Chikara, E-mail: ti-sato@aist.go.jp [Biomedical Research Institute, National Institute of Industrial Science and Technology (AIST), 1-1-1 Higashi, Tsukuba 305-8566 (Japan)

    2014-08-01

    Correlative light-electron microscopy of cells in a natural environment of aqueous liquid facilitates high-throughput observation of protein complex formation. ASEM allows the inverted SEM to observe the wet sample from below, while an optical microscope observes it from above quasi-simultaneously. The disposable ASEM dish with a silicon nitride (SiN) film window can be coated variously to realize the primary-culture of substrate-sensitive cells in a few milliliters of culture medium in a stable incubator environment. Neuron differentiation, neural networking, proplatelet-formation and phagocytosis were captured by optical or fluorescence microscopy, and imaged at high resolution by gold-labeled immuno-ASEM with/without metal staining. Fas expression on the cell surface was visualized, correlated to the spatial distribution of F-actin. Axonal partitioning was studied using primary-culture neurons, and presynaptic induction by GluRδ2-N-terminus-linked fluorescent magnetic beads was correlated to the presynaptic-marker Bassoon. Further, megakaryocytes secreting proplatelets were captured, and P-selectins with adherence activity were localized to some of the granules present by immuno-ASEM. The phagocytosis of lactic acid bacteria by dendritic cells was also imaged. Based on these studies, ASEM correlative microscopy promises to allow the study of various mesoscopic-scale dynamics in the near future. - Highlights: • In situ correlative light electron microscopy of samples in open solution by ASEM. • Primary cultures for in-solution CLEM by developing SiN-film coating methods • First visualization of fluorescent magnetic beads in aqueous solution by CLEM. • Presynaptic induction of neurons by GluRδ2-N-terminus-coated beads studied by CLEM. • Axonal partitioning, bacterial phagocytosis, platelet formation imaged by CLEM.

  13. The effect of oil sands tailings pond sediments on embryo-larval walleye (Sander vitreus).

    Science.gov (United States)

    Raine, J C; Turcotte, D; Tumber, V; Peru, K M; Wang, Z; Yang, C; Headley, J V; Parrott, J L

    2017-10-01

    Walleye (Sander vitreus) are a commercially important North American fish species that inhabit the Athabasca River. This river flows through the Athabasca oil sands where natural sources of bitumen erode from the McMurray formation. Little information is available on responses of walleye embryos to oil sands tailings pond sediments in a laboratory setting. The current study describes the design and implementation of a daily-renewal bioassay to assess the potential effects of tailings pond sediments from the Athabasca oil sands area on walleye development. Developing walleye embryos were exposed to increasing concentrations of two tailings pond sediments (collected in the Athabasca oil sands area) until the completion of yolk absorption in control fish. Sediments from the tailings pond represent a mixture of polycyclic aromatic hydrocarbons (PAHs) and alkylated PAHs. During the 31 day exposure, the walleye were examined for mortalities, weight, length and developmental abnormalities to provide an initial evaluation of the effects of the oil sands tailings pond sediments. Walleye embryo survival differed between the tailings pond sediments, and survival decreased with increasing sediment concentration. Alkylated PAH content differed between the two tailings pond sediments and lower embryo survival corresponded to higher total and alkylated PAH content. Tailings pond sediment-exposed walleye exhibited a delay in development, as well as increased percentages of larvae with heart and yolk sac edema, and cranial and spinal malformations. These abnormalities in development are often associated with PAH and alkylated PAH exposure. This study provides an exposure design that can be used to assess sediment toxicity to early developmental stages of a fish species not commonly tested in the lab, and lays the groundwork for future studies with this and other difficult-to-culture species. These results offer information on the potential effects of tailings pond sediments

  14. Review of SERI Solar Pond Work

    Science.gov (United States)

    Zangrando, F.; Johnson, D. H.

    1984-01-01

    Development of models of pond thermal performance; analysis of solar pond use for building space heat and hot water production; use of low-temperature pond-produced heat for industrial processes, desalination, and electricity production; development of direct-contact heat exchanger to reduce conversion equipment cost; determination of effects of extracted heat and mass from the storage layer on pond performance; and investigation of factors which determine gradient layer stability and the stability of this interface between this level and the upper and lower convecting layers were described.

  15. Visualization of Mesenchymal Stromal Cells in 2Dand 3D-Cultures by Scanning Electron Microscopy with Lanthanide Contrasting.

    Science.gov (United States)

    Novikov, I A; Vakhrushev, I V; Antonov, E N; Yarygin, K N; Subbot, A M

    2017-02-01

    Mesenchymal stromal cells from deciduous teeth in 2D- and 3D-cultures on culture plastic, silicate glass, porous polystyrene, and experimental polylactoglycolide matrices were visualized by scanning electron microscopy with lanthanide contrasting. Supravital staining of cell cultures with a lanthanide-based dye (neodymium chloride) preserved normal cell morphology and allowed assessment of the matrix properties of the carriers. The developed approach can be used for the development of biomaterials for tissue engineering.

  16. A Study of Ecological Conducts under Cultural Adaption: A Case Study of Construction of Fish Ponds in Huanggang Dong Community of Guizhou%文化适应下的生态行为研究——以贵州黄岗侗族社区的鱼塘建构为例

    Institute of Scientific and Technical Information of China (English)

    彭书佳

    2012-01-01

    in the process of cultural adaptation, any kind of culture has the functions of creating and maintaining. To one nation, regardless of its size, it has its own living space on the surface of the earth. Meanwhile, the natural features of this unique living space constitute this nation's natural hving environment. For Dong people in Huanggang, which is an area not suitable for an artificial habitat change, after a long period of exploration, through man - made means of changing the fiver courses and digging fish ponds, it helped to reserve resources from the fish ponds. At the same time, it has fully verified Dong people's ecological wisdom when dealing with the relationship properly between resources and environment.%在文化适应的过程中,任何一种文化都具有其创造性与保持性。对一个民族来说,它在地球表面上必有其自己的生存发展空间,这片特有空间的自然特性就构成了该民族的自然生存环境。黄岗侗族人民在一个地表崎岖不平、人为改变生存环境困难的地区,经过长期的探索,通过人工手段改变河道、挖掘鱼塘,并使得建构的鱼塘得到了精心的维护,这其间充分验证了侗族人民正确协调资源与环境之间关系的生态智慧。

  17. Mercury assessment of Brandy Pond T39 MD, Maine

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Brandy Pond is a remote, shallow, pond in east‐central Maine. A bald eagle (Haliaeetus leucocephalus) nest territory has existed on the pond since the mid-1960s....

  18. [Diurnal variations of greenhouse gas fluxes at the water-air interface of aquaculture ponds in the Min River estuary].

    Science.gov (United States)

    Yang, Ping; Tong, Chuan; He, Qing-Hua; Huang, Jia-Fang

    2012-12-01

    Wetland reclamation and aquaculture is one of the main disturbance types in coastal wetlands. Diurnal variations of CO2, CH4 and N2O fluxes at the water-air interface were determined using a floating chambers + gas chromatography method in a shrimp pond, and a mixed culture pond of fish and shrimp in October in the Shanyutan Wetland of the Min River estuary, southeast China. Meanwhile, the meteorological indicators in ground surface and physical, chemical and biological indicators of surface water were also measured. CO2, CH4 and N2O fluxes at the water-air interface all demonstrated distinct diurnal variations. Both shrimp pond and mixed culture pond of fish and shrimp functioned as a sink of CO2 [the diurnal averaged CO2 fluxes were -48.79 and -105.25 mg x (m2 x h)(-1), respectively], and a source of CH4 [the diurnal averaged CH4 fluxes were 1.00 and 5.74 mg x (m2 x h)(-1), respectively]; the diurnal averaged CO2 and CH4 fluxes at the water-air interface of the mixed culture of fish and shrimp pond were higher than that of the shrimp pond. Greenhouse gas fluxes at the water-air interface from the aquaculture ponds were influenced by many factors. Multiple stepwise regression analysis showed that the concentration of Chlorophyll was the major factor affecting the CO2 fluxes, and the concentrations of SO4(2-) and PO4(3-) were the major factors affecting the CH4 fluxes at the water-air interface of the shrimp pond; whereas water temperature and Chlorophyll were the major factors affecting the CO2 fluxes, and dissolved oxygen, PO4(3-) and pH were the major factors affecting the CH4 fluxes at the water-air interface of the mixed culture pond of fish and shrimp.

  19. Performing sound of the past: Remix in electronic dance music culture

    Directory of Open Access Journals (Sweden)

    Cvijanović Irina

    2014-01-01

    Full Text Available The term remix, defined as an activity of taking data from pre-existing materials to combine them into new forms according to personal taste, relates to various elements and areas of contemporary culture. Whichever model used, consideration of the remix depends on recognition of pre-existing cultural codes. Therefore, as a second layer, the remix relies on the authority of the original and it functions at the meta-level. The audience may see a trace of history with the pre-existing object and the meaning creates in the viewer(s, reader(s, listener(s or, in the contemporary world of DJs and popular electronic dance music culture - in dancer(s. With the aim of specifying modes of creating particular ambients, this paper will consider and examine the song Why Don’t You? remixed by Marko Milićević, a Serbian DJ also known as Gramophonedzie, and illuminate how material from the past can create a constructive (musical dialogue.

  20. Sydney Tar Ponds Remediation: Experience to China

    Science.gov (United States)

    Liu, Fan; Bryson, Ken A.

    2009-01-01

    The infamous "Sydney Tar Ponds" are well known as one of the largest toxic waste sites of Canada, due to almost 100 years of steelmaking in Sydney, a once beautiful and peaceful city located on the east side of Cape Breton Island, Nova Scotia. This article begins with a contextual overview of the Tar Ponds issue including a brief introduction and…

  1. 100-D Ponds closure plan. Revision 1

    Energy Technology Data Exchange (ETDEWEB)

    Petersen, S.W.

    1997-09-01

    The 100-D Ponds is a Treatment, Storage, and Disposal (TSD) unit on the Hanford Facility that received both dangerous and nonregulated waste. This Closure Plan (Rev. 1) for the 100-D Ponds TSD unit consists of a RCRA Part A Dangerous Waste Permit Application (Rev. 3), a RCRA Closure Plan, and supporting information contained in the appendices to the plan. The closure plan consists of eight chapters containing facility description, process information, waste characteristics, and groundwater monitoring data. There are also chapters containing the closure strategy and performance standards. The strategy for the closure of the 100-D Ponds TSD unit is clean closure. Appendices A and B of the closure plan demonstrate that soil and groundwater beneath 100-D Ponds are below cleanup limits. All dangerous wastes or dangerous waste constituents or residues associated with the operation of the ponds have been removed, therefore, human health and the environment are protected. Discharges to the 100-D Ponds, which are located in the 100-DR-1 operable unit, were discontinued in June 1994. Contaminated sediment was removed from the ponds in August 1996. Subsequent sampling and analysis demonstrated that there is no contamination remaining in the ponds, therefore, this closure plan is a demonstration of clean closure.

  2. Pond of Illusion: Interacting through Mixed Reality

    DEFF Research Database (Denmark)

    Nobel-Jørgensen, Morten; Nielsen, Jannik Boll; Larsen, Anders Boesen Lindbo

    2013-01-01

    to a large display in either of the real spaces by allowing them to feed virtual fish swimming in the pond. Figure 1(middle) shows how a Microsoft Kinect mounted on top of the display is used for detecting throw motions, which triggers virtual breadcrumbs to be thrown into the pond for feeding the nearby...

  3. Organic matter decomposition in simulated aquaculture ponds

    NARCIS (Netherlands)

    Torres Beristain, B.

    2005-01-01

    Different kinds of organic and inorganic compounds (e.g. formulated food, manures, fertilizers) are added to aquaculture ponds to increase fish production. However, a large part of these inputs are not utilized by the fish and are decomposed inside the pond. The microbiological decomposition of the

  4. Methodological approach for the collection and simultaneous estimation of greenhouse gases emission from aquaculture ponds.

    Science.gov (United States)

    Vasanth, Muthuraman; Muralidhar, Moturi; Saraswathy, Ramamoorthy; Nagavel, Arunachalam; Dayal, Jagabattula Syama; Jayanthi, Marappan; Lalitha, Natarajan; Kumararaja, Periyamuthu; Vijayan, Koyadan Kizhakkedath

    2016-12-01

    Global warming/climate change is the greatest environmental threat of our time. Rapidly developing aquaculture sector is an anthropogenic activity, the contribution of which to global warming is little understood, and estimation of greenhouse gases (GHGs) emission from the aquaculture ponds is a key practice in predicting the impact of aquaculture on global warming. A comprehensive methodology was developed for sampling and simultaneous analysis of GHGs, carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O) from the aquaculture ponds. The GHG fluxes were collected using cylindrical acrylic chamber, air pump, and tedlar bags. A cylindrical acrylic floating chamber was fabricated to collect the GHGs emanating from the surface of aquaculture ponds. The sampling methodology was standardized and in-house method validation was established by achieving linearity, accuracy, precision, and specificity. GHGs flux was found to be stable at 10 ± 2 °C of storage for 3 days. The developed methodology was used to quantify GHGs in the Pacific white shrimp Penaeus vannamei and black tiger shrimp Penaeus monodon culture ponds for a period of 4 months. The rate of emission of carbon dioxide was found to be much greater when compared to other two GHGs. Average GHGs emission in gha(-1) day(-1) during the culture was comparatively high in P.vannamei culture ponds.

  5. Intermediate pond sizes contain the highest density, richness, and diversity of pond-breeding amphibians.

    Directory of Open Access Journals (Sweden)

    Raymond D Semlitsch

    Full Text Available We present data on amphibian density, species richness, and diversity from a 7140-ha area consisting of 200 ponds in the Midwestern U.S. that represents most of the possible lentic aquatic breeding habitats common in this region. Our study includes all possible breeding sites with natural and anthropogenic disturbance processes that can be missing from studies where sampling intensity is low, sample area is small, or partial disturbance gradients are sampled. We tested whether pond area was a significant predictor of density, species richness, and diversity of amphibians and if values peaked at intermediate pond areas. We found that in all cases a quadratic model fit our data significantly better than a linear model. Because small ponds have a high probability of pond drying and large ponds have a high probability of fish colonization and accumulation of invertebrate predators, drying and predation may be two mechanisms driving the peak of density and diversity towards intermediate values of pond size. We also found that not all intermediate sized ponds produced many larvae; in fact, some had low amphibian density, richness, and diversity. Further analyses of the subset of ponds represented in the peak of the area distribution showed that fish, hydroperiod, invertebrate density, and canopy are additional factors that drive density, richness and diversity of ponds up or down, when extremely small or large ponds are eliminated. Our results indicate that fishless ponds at intermediate sizes are more diverse, produce more larvae, and have greater potential to recruit juveniles into adult populations of most species sampled. Further, hylid and chorus frogs are found predictably more often in ephemeral ponds whereas bullfrogs, green frogs, and cricket frogs are found most often in permanent ponds with fish. Our data increase understanding of what factors structure and maintain amphibian diversity across large landscapes.

  6. Intermediate pond sizes contain the highest density, richness, and diversity of pond-breeding amphibians.

    Science.gov (United States)

    Semlitsch, Raymond D; Peterman, William E; Anderson, Thomas L; Drake, Dana L; Ousterhout, Brittany H

    2015-01-01

    We present data on amphibian density, species richness, and diversity from a 7140-ha area consisting of 200 ponds in the Midwestern U.S. that represents most of the possible lentic aquatic breeding habitats common in this region. Our study includes all possible breeding sites with natural and anthropogenic disturbance processes that can be missing from studies where sampling intensity is low, sample area is small, or partial disturbance gradients are sampled. We tested whether pond area was a significant predictor of density, species richness, and diversity of amphibians and if values peaked at intermediate pond areas. We found that in all cases a quadratic model fit our data significantly better than a linear model. Because small ponds have a high probability of pond drying and large ponds have a high probability of fish colonization and accumulation of invertebrate predators, drying and predation may be two mechanisms driving the peak of density and diversity towards intermediate values of pond size. We also found that not all intermediate sized ponds produced many larvae; in fact, some had low amphibian density, richness, and diversity. Further analyses of the subset of ponds represented in the peak of the area distribution showed that fish, hydroperiod, invertebrate density, and canopy are additional factors that drive density, richness and diversity of ponds up or down, when extremely small or large ponds are eliminated. Our results indicate that fishless ponds at intermediate sizes are more diverse, produce more larvae, and have greater potential to recruit juveniles into adult populations of most species sampled. Further, hylid and chorus frogs are found predictably more often in ephemeral ponds whereas bullfrogs, green frogs, and cricket frogs are found most often in permanent ponds with fish. Our data increase understanding of what factors structure and maintain amphibian diversity across large landscapes.

  7. A Comparison of Nannochloropsis salina Growth Performance in Two Outdoor Pond Designs: Conventional Raceways versus the ARID Pond with Superior Temperature Management

    Directory of Open Access Journals (Sweden)

    Braden Crowe

    2012-01-01

    Full Text Available The present study examines how climatic conditions and pond design affect the growth performance of microalgae. From January to April of 2011, outdoor batch cultures of Nannochloropsis salina were grown in three replicate 780 L conventional raceways, as well as in an experimental 7500 L algae raceway integrated design (ARID pond. The ARID culture system utilizes a series of 8–20 cm deep basins and a 1.5 m deep canal to enhance light exposure and mitigate temperature variations and extremes. The ARID culture reached the stationary phase 27 days earlier than the conventional raceways, which can be attributed to its superior temperature management and shallower basins. On a night when the air temperature dropped to −9°C, the water temperature was 18°C higher in the ARID pond than in the conventional raceways. Lipid and fatty acid content ranged from 16 to 25% and from 5 to15%, respectively, as a percentage of AFDW. Palmitic, palmitoleic, and eicosapentaenoic acids comprised the majority of fatty acids. While the ARID culture system achieved nearly double the volumetric productivity relative to the conventional raceways (0.023 versus 0.013 g L−1day−1, areal biomass productivities were of similar magnitude in both pond systems (3.47 versus 3.34 g m−2day−1, suggesting that the ARID pond design has to be further optimized, most likely by increasing the culture depth or operating at higher cell densities while maintaining adequate mixing.

  8. Application of Constructed Wetlands on Wastewater Treatment for Aquaculture Ponds

    Institute of Scientific and Technical Information of China (English)

    LI Gu; WU Zhenbin; CHENG Shuiping; LIANG Wei; HE Feng; FU Guiping; ZHONG Fei

    2007-01-01

    A group of constructed wetlands (CWs) were applied to the recirculating aquaculture system. This study assessed the performance of CWs in treating the aquaculture wastewater, examined the water quality condition of aquaculture ponds and the growth and the survival rate of "target" species(Ictalurus punctatus and Megalobrama amblycephala). The results showed that CWs were effective on reducing the concentrations of 5-day biochemical oxygen demand (BOD5, at 70.5%), total suspended solids (TSS, at 81.9%),chlorophyll a (Chl-a, at 91.9%), ammonium (NH4+, at 61.5%) and nitrate nitrogen (NO3--N, at 68.0%). Effect of CWs on phosphate (PO43- -P) removal was relatively lower (at 20.0%). The concentrations of BOD5, TSS, Chl-a, NH4+ and TN, TP in the recirculating culture pond were significantly lower than that in the control pond( p < 0.05 ). CWs could help to increase total yield, survival rate of the "target" species and significantly decrease feed conversion ratio ( p < 0.05 ).

  9. Study of free radicals in gamma irradiated cellulose of cultural heritage materials using Electron Paramagnetic Resonance

    Science.gov (United States)

    Kodama, Yasko; Rodrigues, Orlando, Jr.; Garcia, Rafael Henrique Lazzari; Santos, Paulo de Souza; Vasquez, Pablo A. S.

    2016-07-01

    Main subject of this article was to study room temperature stable radicals in Co-60 gamma irradiated contemporary paper using Electron Paramagnetic Resonance spectrometer (EPR). XRD was used to study the effect of ionizing radiation on the morphology of book paper. SEM images presented regions with cellulose fibers and regions with particles agglomeration on the cellulose fibers. Those agglomerations were rich in calcium, observed by EDS. XRD analysis confirmed presence of calcium carbonate diffraction peaks. The main objective of this study was to propose a method using conventional kinetics chemical reactions for the observed radical formed by ionizing radiation. Therefore, further analyses were made to study the half-life and the kinetics of the free radical created. This method can be suitably applied to study radicals on cultural heritage objects.

  10. Impact of the introduction of electronic prescribing on staff perceptions of patient safety and organizational culture.

    Science.gov (United States)

    Davies, James; Pucher, Philip H; Ibrahim, Heba; Stubbs, Ben

    2017-05-15

    Electronic prescribing (EP) systems are online technology platforms by which medicines can be prescribed, administered, and stock controlled. The actual impact of EP on patient safety is not truly understood. This study seeks to assess the impact of the implementation of an EP system on safety culture, as well as assessing differences between clinical respondent groups and considering their implications. Staff completed a modified Safety Attitudes Questionnaire survey, 6 weeks following the introduction of EP across surgical services in a hospital in Dorset, England. Responses were assessed and differences between respondent groups compared. Rates of self-reported adverse events were compared before and after implementation. Overall response rate was 34.5%. There was no significant difference between usage patterns and previous experience with EP between user groups. Overall safety was felt to have been reduced by the introduction of EP. Significant differences between clinician and nonclinicians were seen in ability to discuss errors (3.23 ± 0.5 versus 2.8 ± 0.69, P = 0.004), drug chart access, and ease of medication prescribing. Regression analysis did not identify any confounding factors. Despite a significant reduction in the adverse event rate in other divisions of the hospital that did not implement EP at the same time, this same reduction was not seen in the surgical department. This is the first study to assess the impact of EP on safety culture using a validated assessment tool (Safety Attitudes Questionnaire). Overall safety culture deteriorated following introduction of EP. Problems with system usability/intuitiveness, nonstandardized implementation, and competence assessment strategies may have all contributed to this result. Centers seeking to implement EP in future must consider these factors to ensure a positive impact on patient safety and outcomes. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. CO₂ efflux from shrimp ponds in Indonesia.

    Science.gov (United States)

    Sidik, Frida; Lovelock, Catherine E

    2013-01-01

    The conversion of mangrove forest to aquaculture ponds has been increasing in recent decades. One of major concerns of this habitat loss is the release of stored 'blue' carbon from mangrove soils to the atmosphere. In this study, we assessed carbon dioxide (CO₂) efflux from soil in intensive shrimp ponds in Bali, Indonesia. We measured CO₂ efflux from the floors and walls of shrimp ponds. Rates of CO₂ efflux within shrimp ponds were 4.37 kg CO₂ m⁻² y⁻¹ from the walls and 1.60 kg CO₂ m⁻² y⁻¹ from the floors. Combining our findings with published data of aquaculture land use in Indonesia, we estimated that shrimp ponds in this region result in CO₂ emissions to the atmosphere between 5.76 and 13.95 Tg y⁻¹. The results indicate that conversion of mangrove forests to aquaculture ponds contributes to greenhouse gas emissions that are comparable to peat forest conversion to other land uses in Indonesia. Higher magnitudes of CO₂ emission may be released to atmosphere where ponds are constructed in newly cleared mangrove forests. This study indicates the need for incentives that can meet the target of aquaculture industry without expanding the converted mangrove areas, which will lead to increased CO₂ released to atmosphere.

  12. CO₂ efflux from shrimp ponds in Indonesia.

    Directory of Open Access Journals (Sweden)

    Frida Sidik

    Full Text Available The conversion of mangrove forest to aquaculture ponds has been increasing in recent decades. One of major concerns of this habitat loss is the release of stored 'blue' carbon from mangrove soils to the atmosphere. In this study, we assessed carbon dioxide (CO₂ efflux from soil in intensive shrimp ponds in Bali, Indonesia. We measured CO₂ efflux from the floors and walls of shrimp ponds. Rates of CO₂ efflux within shrimp ponds were 4.37 kg CO₂ m⁻² y⁻¹ from the walls and 1.60 kg CO₂ m⁻² y⁻¹ from the floors. Combining our findings with published data of aquaculture land use in Indonesia, we estimated that shrimp ponds in this region result in CO₂ emissions to the atmosphere between 5.76 and 13.95 Tg y⁻¹. The results indicate that conversion of mangrove forests to aquaculture ponds contributes to greenhouse gas emissions that are comparable to peat forest conversion to other land uses in Indonesia. Higher magnitudes of CO₂ emission may be released to atmosphere where ponds are constructed in newly cleared mangrove forests. This study indicates the need for incentives that can meet the target of aquaculture industry without expanding the converted mangrove areas, which will lead to increased CO₂ released to atmosphere.

  13. Modeling environmental and human health risks of veterinary medicinal products applied in pond aquaculture.

    Science.gov (United States)

    Rico, Andreu; Geng, Yue; Focks, Andreas; Van den Brink, Paul J

    2013-04-01

    A model called ERA-AQUA was developed to assess the risks posed by the use of veterinary medicinal products (VMPs) applied in aquaculture ponds for the targeted produce, surrounding aquatic ecosystems, consumers, and trade of the aquaculture produce. The model calculates risks by following a risk quotient approach, calculating predicted exposure concentrations (exposure assessment) and predicted no-effect concentrations (effect assessment) for the endpoint under study. The exposure assessment is performed by combining information on the environmental characteristics of the aquaculture pond, characteristics of the cultured species, aquaculture management practices, and physicochemical properties of the compound under study. The model predicts concentrations of VMPs in the pond water, pond sediment, cultured species, and watercourse receiving pond effluent discharges by mass balance equations. The effect assessment is performed by combining (eco)toxicological information and food safety threshold concentrations for the studied compound. In the present study, the scientific background, strengths, and limitations of the ERA-AQUA model are presented together with a sensitivity analysis and an example showing its potential applications.

  14. Solar ponds. Citations from the NTIS data base

    Science.gov (United States)

    Hundemann, A. S.

    1980-08-01

    Federally funded research on the design, performance, and use of solar ponds is discussed on these. Topic areas cover the use of solar ponds in industrial process heat production, roof ponds for passive solar buildings, and solar ponds use in the production of biomass for renewable fuels.

  15. Direct Measurements of Oxygen Gradients in Spheroid Culture System Using Electron Parametric Resonance Oximetry.

    Directory of Open Access Journals (Sweden)

    Laura M Langan

    Full Text Available Advanced in vitro culture from tissues of different origin includes three-dimensional (3D organoid micro structures that may mimic conditions in vivo. One example of simple 3D culture is spheroids; ball shaped structures typically used as liver and tumour models. Oxygen is critically important in physiological processes, but is difficult to quantify in 3D culture: and the question arises, how small does a spheroid have to be to have minimal micro-environment formation? This question is of particular importance in the growing field of 3D based models for toxicological assessment. Here, we describe a simple non-invasive approach modified for the quantitative measurement and subsequent evaluation of oxygen gradients in spheroids developed from a non-malignant fish cell line (i.e. RTG-2 cells using Electron Paramagnetic Resonance (EPR oximetry. Sonication of the paramagnetic probe Lithium phthalocyanine (LiPc allows for incorporation of probe particulates into spheroid during its formation. Spectra signal strength after incorporation of probe into spheroid indicated that a volume of 20 μl of probe (stock solution: 0.10 mg/mL is sufficient to provide a strong spectra across a range of spheroid sizes. The addition of non-toxic probes (that do not produce or consume oxygen report on oxygen diffusion throughout the spheroid as a function of size. We provide evidence supporting the use of this model over a range of initial cell seeding densities and spheroid sizes with the production of oxygen distribution as a function of these parameters. In our spheroid model, lower cell seeding densities (∼2,500 cells/spheroid and absolute size (118±32 μm allow control of factors such as pre-existing stresses (e.g. ∼ 2% normoxic/hypoxic interface for more accurate measurement of treatment response. The applied methodology provides an elegant, widely applicable approach to directly characterize spheroid (and other organoid cultures in biomedical and

  16. The research of 4th grade mathematical curriculum electronic picture book construction and development in integrating indigenous culture

    Science.gov (United States)

    Chen, Yen Ting; Hsin Wang, Juei

    2017-02-01

    This research aimed at integrating Seediq culture and mathematical course design for fourth-grade elementary school, and then transforming this mathematical course into an electronic picture book. During the process of electronic book development, the researchers collected videos of six participants engaged in discussion, reflection minutes after the meeting written by the attendants, the researchers' observation and review journals, and conversations with the participants. Then, researchers utilized Content Analysis to explore, try, review and retry steps of electronic book making process. The main findings: There are four periods of electronic book making process, research occurrence period, curriculum design period, electronic book transformation period, and result evaluation period. The picture book included the White Stone Legend born from Seediq seniors, historical battle for hunting field between tribes, and concepts of approximation, angle, triangle, and quadrangle features. At last, with the research result, this article presents the corroboration of related works, and then proposes suggestions of electronic book teaching and follow-up studies.

  17. [Variation of bacteria numbers in fish-shrimp mix-culturing ecosystem].

    Science.gov (United States)

    Li, Qiufen; Chen, Bijuan; Qu, Keming; Yuan, Youxian; Li, Jian; Sun, Xiutao; Zhao, Fazhen

    2002-06-01

    The study on variation of bacteria numbers in Penaeus chinensis-fish mix-culturing ecosystem in 1997. Indicated that at the beginning of culturing season, total number of heterotrophic bacteria and that of nitrate-reducing bacteria in mix-culturing ponds was low, but it was higher than that in mono-culturing shrimp pond. With time going on, the number of bacteria in mono-culturing pond increased rapidly and remained at a high level in August and September, an that in mix-culturing ponds also increased. But the latter increased slowly, and it was never over 10(4) cells.ml-1 and dropped in September. Number of bacteria in bottom of the ponds varied with the similar regulation, but the numbers was 10-100 times higher. The numbers of vibrio in mix-culturing ponds was always lower than that in contrastive pond at the same time. So, in fish-shrimp mix-culturing ponds, the contents of organic matter were lower and the total amount and variability of phytoplankton were higher than corresponding items in mono-culturing pond. It was concluded that mix-culture could stimulate and control the growth of heterotrophic bacteria, accelerate the degradation of organic pollutants, consequently fasten and stabilize the circulation of mater in ecosystem of ponds in culturing season.

  18. 78 FR 23949 - Sunkhaze Meadows National Wildlife Refuge and Carlton Pond Waterfowl Production Area, Penobscot...

    Science.gov (United States)

    2013-04-23

    ... and Carlton Pond WPA. We started this process through a notice in the Federal Register (76 FR 14984... Milford Town Hall and one public meeting at Unity College during the formal public scoping period... protect cultural resources. In addition, we have made the preliminary determination that Sunkhaze...

  19. Status report on Fish Springs pond snail

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report provides a life history of the pond snail (Lymnaea Hinkleyia pilsbryi) at Fish Springs National Wildlife Refuge. The following information is included;...

  20. South Bay Salt Ponds : Initial stewardship plan

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The California Department of Fish and Game and the U.S. Fish and Wildlife Service will operate and maintain the South Bay Salt Ponds under this Initial Stewardship...

  1. Two Ponds Canal Realignment Conceptual Planning

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Tetra Tech RMC has preformed storm routing calculations, prepared a conceptual grading plan, and developed a preliminary cost estimate. Additionally, pond sizing and...

  2. LIFE CYCLE COST ANALYSIS OF SOLAR PONDS

    Directory of Open Access Journals (Sweden)

    Murat ÖZTÜRK

    2008-03-01

    Full Text Available Solar ponds are the systems which collect solar energy and store it for long periods of time. For effective and efficient use of these systems in the country, concepts relating economy of solar ponds which generated hot water from the sun must be known besides their physical properties. Life cycle cost analysis is a systematic analytical method that helps identify and evaluate the environmental impacts of a specific process or competing processes. In order to quantify the costs, resource consumption, and energy use, material and energy balances are performed in a cradle-to-grave manner on the operations required to transform raw materials into useful products. In this study; life cycle cost analysis of reflecting covered and non covered solar ponds are calculated for a volume of 3.5x3.5x2 cubic meters and presented. Also the energies extractable for these solar ponds in Goller Region climatic conditions are given.

  3. Wintertime Emissions from Produced Water Ponds

    Science.gov (United States)

    Evans, J.; Lyman, S.; Mansfield, M. L.

    2013-12-01

    Every year oil and gas drilling in the U.S. generates billions of barrels of produced water (water brought to the surface during oil or gas production). Efficiently disposing of produced water presents a constant financial challenge for producers. The most noticeable disposal method in eastern Utah's Uintah Basin is the use of evaporation ponds. There are 427 acres of produced water ponds in the Uintah Basin, and these were used to evaporate more than 5 million barrels of produced water in 2012, 6% of all produced water in the Basin. Ozone concentrations exceeding EPA standards have been observed in the Uintah Basin during winter inversion conditions, with daily maximum 8 hour average concentrations at some research sites exceeding 150 parts per billion. Produced water contains ozone-forming volatile organic compounds (VOC) which escape into the atmosphere as the water is evaporated, potentially contributing to air quality problems. No peer-reviewed study of VOC emissions from produced water ponds has been reported, and filling this gap is essential for the development of accurate emissions inventories for the Uintah Basin and other air sheds with oil and gas production. Methane, carbon dioxide, and VOC emissions were measured at three separate pond facilities in the Uintah Basin in February and March of 2013 using a dynamic flux chamber. Pond emissions vary with meteorological conditions, so measurements of VOC emissions were collected during winter to obtain data relevant to periods of high ozone production. Much of the pond area at evaporation facilities was frozen during the study period, but areas that actively received water from trucks remained unfrozen. These areas accounted for 99.2% of total emissions but only 9.5% of the total pond area on average. Ice and snow on frozen ponds served as a cap, prohibiting VOC from being emitted into the atmosphere. Emissions of benzene, toluene, and other aromatic VOCs averaged over 150 mg m-2 h-1 from unfrozen pond

  4. Material Selection Considerations for Solar Ponds

    Science.gov (United States)

    Sastri, S.; Vaidyanathan, T. K.; Marsh, H. E.; French, R. L.

    1984-01-01

    Among the various candidate materials tested, stainless steel shows the best potential for applications as heat exchanger components in solar ponds. Even stainless steel may lead to pitting type of corrosion. Weight loss measurements are probably unsatisfactory for corrosion evaluation in solar pond situations. Also included are the results from the potentiodynamic anodic polarization analysis, corrosion rate calculation via corrosion behavior diagrams, and immersion weight loss measurements.

  5. Pits, pipes, ponds--and me.

    Science.gov (United States)

    Mara, Duncan

    2013-05-01

    My life in low-cost sanitation and low-cost wastewater treatment and the use of treated wastewater in agriculture and aquaculture really has been 'pits, pipes and ponds' - 'pits' are low-cost sanitation technologies (LCST) such as VIP latrines and pour-flush toilets; 'pipes' are low-cost sewerage, principally condominial (simplified) sewerage; and 'ponds' are low-cost wastewater treatment systems, especially waste stabilization ponds, and the use of treated wastewater in agriculture and aquaculture. 'Pits' were mainly working on World Bank LCST research projects, with fieldwork principally in Zimbabwe, 'pipes' were working on condominial sewerage projects in Brazil and disseminating this LCST to a wider global audience, and 'ponds' were waste stabilization ponds, with fieldwork mainly in Brazil, Colombia, Portugal and the United Kingdom, the development of aerated rock filters to polish facultative-pond effluents, and the human-health aspects of treated wastewater use in agriculture and aquaculture, with fieldwork in Brazil and the UK, and the application of quantitative microbial risk analysis. The paper provides a professional perspective and lessons from historical developments and gives recommended future directions based on my career working on low-cost sanitation technologies and treated wastewater use in agriculture and aquaculture.

  6. 养殖池塘系统脱氮硫杆菌(Thiobacillus denitrificans)的分离、生长特性及脱氮特征研究%Isolation and Culture of Thiobacillus denitrificans from Different Area of the Intensive Pond System and Their Capacities of Removing Nitrate

    Institute of Scientific and Technical Information of China (English)

    范立民; 裘丽萍; 陈家长; 宋超; 胡庚东; 瞿建宏; 孟顺龙; 吴伟

    2013-01-01

    分别采集集约化养殖吉富罗非鱼(Oreochromis niloticus)的池塘底泥、表层水、塘边裸露土壤样品,采用脱氮硫杆菌选择培养基富集培养、分离得到3株细菌,通过菌落特征、形态学特征、生理生化检验和16S rDNA序列分析等手段,鉴定为脱氮硫杆菌(Thiobacillus denitrificans),命名为TD1、TD2和TD3.在30℃下,采用静置、厌氧培养实验研究这3株脱氮硫杆菌的生长繁殖特征、对硝酸盐氮的去除速率特征、硫酸根产生状况、亚硝酸盐产生情况、培养液pH值和氧化还原电位变化特征等方面的差异进行研究,探索养殖环境修复中应用的可能性.结果表明:在一定的时间内菌株生长速率、介质pH降低速率和氧化还原电位上升幅度均表现为TD1>TD2>TD3;菌株硝态氮脱除效率和硫酸根浓度升高速率均表现为TD1>TD2>TD3,亚硝酸盐产生情况则表现为TD1<TD2<TD3;TD1更适合异位修复,TD2更适合原位修复.%In this study, an intensive pond in which GIFT tilapia( Oreochromis niloticus ) were cultured was used. And sampling were done in different areas of the pond system, including sediments of the pond, the waters 50 centimeters below the surface and the bare soil at the edge of the pond. After that, enrichment and elective cultures were prepared anaerobically on these samples in 30 centigrade by incubating glass-stoppered bottles with the medium for Thiobacillus denitrificans full filled. After the culture, by using the spread-plate method, three strains were got. Through the appearance of the colonies, the shape of the strains, the detection of physiological and biochemical indicators, and the analysis of the sequences of 16S rDNA, the strains was identified as Thiobacillus denitrificans, and they were named as TD1, TD2 and TD3. Through the studies on the characteristics of growth and reproduction, of the removing rates of the nitrate, of the production of the sulfate and nitrite, and of

  7. Advantages of indium-tin oxide-coated glass slides in correlative scanning electron microscopy applications of uncoated cultured cells.

    NARCIS (Netherlands)

    Pluk, H.; Stokes, D.J.; Lich, B.; Wieringa, B.; Fransen, J.A.M.

    2009-01-01

    A method of direct visualization by correlative scanning electron microscopy (SEM) and fluorescence light microscopy of cell structures of tissue cultured cells grown on conductive glass slides is described. We show that by growing cells on indium-tin oxide (ITO)-coated glass slides, secondary elect

  8. Anaerobic biodegradation of benzene series compounds by mixed cultures based on optional electronic acceptors

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    A series of batch experiments were performed using mixed bacterial consortia to investigate biodegradation performance of benzene,toluene,ethylbenzene and three xylene isomers (BTEX) under nitrate,sulfate and ferric iron reducing conditions.The results showed that toluene,ethylbenzeoe,m-xylene and o-xylene could be degraded independently by the mixed cultures coupled to nitrate,sulfate and ferric iron reduction.Under ferric iron reducing conditions the biodegradation of benzene and p-xylene could be occurred only in the presence of other alkylbenzenes.Alkylbenzenes can serve as the primary substrates to stimulate the transformation of benzene and p-xylene under anaerobic conditions.Benzene and p-xylene are more toxic than toluene and ethylbenzene,under the three terminal electron acceptors conditions,the degradation rates decreased with toluene > ethylbenzene > m-xylene > o-xylene > benzene > p-xylene.Nitrate was a more favorable electron acceptor compared to sulfate and ferric iron.The ratio between sulfate consumed and the loss of benzene,toluene,ethylbenzene,o-xylene,m-xylene,p-xylene was 4.44,4.51,4.42,4.32,4.37 and 4.23,respectively;the ratio between nitrate consumed and the loss of these substrates was 7.53,6.24,6.49,7.28,7.81,7.61,respectively;the ratio between the consumption of ferric iron and the loss of toluene,ethylbenzene,o-xylene,m-xylenewas 17.99,18.04,18.07,17.97,respectively.

  9. INCREASING FISH PRODUCTIVITY OF POND ECOSYSTEMS BY FERTILIZING THEM WITH DISTILLER'S GRAINS

    Directory of Open Access Journals (Sweden)

    N. Tson’

    2015-03-01

    Full Text Available Purpose. To study fish culture parameters of young-of-the-year carp in the conditions of industrial fish-growing ponds when applying experimental repeated fertilization with distiller’s grain. Methodology. The study was conducted in industrial fish-growing ponds. The wastes of alcohol industry – the distiller’s grain as organic fertilizer was gradually introduced into ponds at following amounts: first application – 1,0 t/ha, second application in 10 days – 0,5 t/ha, third application in 12 days – 0,5 t/ha. The control ponds were fertilized with humus (2 t/ha. Young-of-the-year carp (Cyprinus carpio were grown in monoculture at stocking density of 30 000 fish/ha. In addition, 100 kg/ha of lime were applied during the culture season in the experiment and control. Fertilization with humus and application of lime in ponds, hydrochemical studies, sampling and processing of hydrobiological samples, fish culturing and statistical studies were carried out according to standard methods. Findings. Gradual fertilizing with distiller’s grain (to the total 2 t/ha gave the possibility to create favorable hydrochemical and hydrobiological regimes. An average daily growth in the experimental fish groups of 0,44 ± 0,09 g/day that was similar to in the control (0,45 ± 0,11 g/day with positive significant correlation between them (r = 0,97; p <0,001 was achieved. The performed measures gave a possibility to obtain fish productivity in the experimental variant 10.7% more than in the control. An economic effect of 14.3% cost reduction for fertilizing ponds was achieved. Originality. For the first time we presented the results of fish culture and biological parameters of young-of-the-year carp in industrial ponds when applying 3-time fertilization with distiller’s grain. Practical Value. The obtained results are the basis for the broad use of non-traditional organic fertilizer – distiller’s grain in industrial ponds, when growing young

  10. EFFECT OF DIFFERENT FERTILIZERS ON THE FORMATION OF HYDROCHEMICAL REGIME IN REARING PONDS

    Directory of Open Access Journals (Sweden)

    T. Hryhorenko

    2016-09-01

    Full Text Available Purpose. To investigate the effect of different types of fertilizers on the formation of hydrochemical regime in rearing ponds. Methodology. For the study, we used generally accepted hydrochemistry methods. For the overall (total chemical analysis, water samples were taken two times during the season (at the beginning and at the end of the growing season, a short chemical analysis of water was carried out twice a month. Findings. The article presents the research results of hydrochemical regime in rearing ponds of the State Enterprise "Nivkа" when applying different types of fertilizers. It was found that hydrochemical regime in experimental rearing ponds was formed under the effect of water supply source and measures aimed at improving the development of the natural food supply (application of cattle manure and microfertilizer "Rostok" Macro. No significant difference was observed between hydrochemical parameters when applying different types of fertilizers. The dynamics of seasonal changes in the basic chemical indicators in both experimental ponds was similar, however, the pond fertilized with manure was characterized by higher values of permanganate oxidation, ammonium and nitrite nitrogen during the entire culture season. In general, the hydrochemical regime in rearing ponds was satisfactory and suitable for the cultivation of carp seeds when applying either cattle manure or microfertilizer "Rostok" Macro. Originality. The peculiarities of the formation of the hydrochemical regime of rearing ponds when applying cattle manure and "Rostock" Macro fertilizer have been investigated. Practical value. The obtained data can be used to develop practical recommendations for the optimization of growing conditions of fish seeds when applying of various types of fertilizers, increasing the efficiency of aquatic ecosystems management and their bioproductivity.

  11. Trace metals in sediments and benthic animals from aquaculture ponds near a mangrove wetland in Southern China.

    Science.gov (United States)

    Wu, Hao; Liu, Jinling; Bi, Xiangyang; Lin, Guanghui; Feng, Christopher C; Li, Zhengjie; Qi, Fei; Zheng, Tianling; Xie, Liqi

    2017-04-15

    In this study, we measured the concentrations of trace metals (Cr, Cu, Zn, As, Cd, Pb and Hg) in typical cultured animals (crabs, clams, and shrimps) and sediments from aquaculture ponds nearby mangrove wetlands in Zhangjiang estuary, China. The contents of Cr, Cu, Cd, and Pb in mangrove sediments were significantly higher than those in pond sediments, while an inverse distribution was observed for Zn, As, and Hg. Significantly higher concentrations of trace metals were found in clams from the mangrove mudflats compared to those from the aquaculture ponds. The sources of trace metals in the clams were primarily from organic fertilizer, whereas those in the shrimp were from contaminated sediment. The results of geo-accumulation index and the ecological risk assessment indicated that the aquaculture ponds near the mangrove wetlands in this subtropical estuary posed a special risk of endogenous and exogenous trace metal pollution to nearby systems. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Electronic repository as а constituent of informative educational space of institutes of higher of culture and sport

    Directory of Open Access Journals (Sweden)

    Iryna Svistel’nik

    2015-06-01

    Full Text Available Purpose: to consider forming and presentation of electronic educational resources on the sites of institutes of higher of physical culture and sport of Ukraine for the informative providing of educational process and scientific researches. Material and Methods: electronic educational methodical materials of departments are analysed on sites of higher physical culture and sport of Ukraine for the opened access students, magistrate. Results: viewing of web pages of libraries of institutes of higher of physical culture and sport of Ukraine allowed to set that majority from them is not formed by electronic collections of educational resources and does not give their remote users. Conclusions: the institutes of higher of physical culture and sport must realize the row of innovations for a grant educational information in the opened access; to modify informative activity in accordance with modern requirements, to initiate and offer new modern informative services for the proper informative providing of education and science in type educational establishments, and also distribution of results of scientific researches.

  13. ISOLATION AND PRELIMINARY IDENTIFICATION OF RHABDOVIRUS FROM CHANNA MACULATA CULTURED IN POND%池塘养殖斑鳢弹状病毒的分离与初步鉴定

    Institute of Scientific and Technical Information of China (English)

    罗霞; 邓国成; 赵长臣; 廖国礼; 陈昆慈; 杨小静

    2013-01-01

    During September, 2010, an unknown disease with highly mortality of over 80% broke out in cultured Channa maculata, at Foshan area of Guangdong province. A strain of rhabdovirus was isolated from the diseased Channa maculata. After the third passage, obvious cytopathic effect (CPE) could be observed in EPC and FHM, inocu-lated with the ultra-filtrate of liver, spleen and kidney from diseased fishes with no bacteria. Mass of bullet-shaped vi-ruses which about 53 nm×140 nm in size, were observed in the ultrathin sections made of infected EPC under electron microscopy. Both artificial infection for healthy Channa maculata with either filtrate of tissues or infected EPC by in-traperitoneal injection caused 100% mortality. The symptoms of the infected fishes were similar to those of natural in-fection. This result indicated that this virus was the lethal pathogen of the fulminant disease. With the primers designed according to the conserved regions of SCRV N gene, specific products with predicted size (400 bp) were obtained from all the diseased tissues and infected cells. Comparative analysis of nucleotide sequences was performed with the Gen-Bank databases using BLAST database network service. The results showed that the gene products shared a highest identity (i.e., 94%) with the corresponding sequence of SCRV [EF575725.1]. On the basis of neighbor-joining analyses of the N gene sequences, phylogenetic tree was constructed with the Clustalx and Mega 4, and it formed a single cluster with SCRV. As their sizes and symptoms of the diseased fishes had some differences, the virus in present research was named as CHRV tentatively.%从患暴发性死亡的斑鳢病灶中分离出一株弹状病毒。取病鱼肝、脾、肾组织过滤液接种EPC、FHM细胞,连续传至第3代后28℃培养35h出现细胞病变(CPE),测得病毒半数细胞感染量为10−5.746/0.1 mL。将病变细胞制成超薄切片,透射电镜下观察到细胞质中存在大量呈子

  14. Heavy metals, PAHs and toxicity in stormwater wet detention ponds

    DEFF Research Database (Denmark)

    Wium-Andersen, Tove; Nielsen, Asbjørn Haaning; Hvitved-Jacobsen, Thorkild

    2011-01-01

    Concentrations of 6 different heavy metals and total Polycyclic Aromatic Hydrocarbons (PAH) were determined in stormwater runoff and in the pond water of two Danish wet detention ponds. The pond water samples were analyzed for toxic effects, using the algae Selenastrum capricornutum as a test......, reducing the potential toxicity of the metal. Another catchment (residential) produced stormwater and pond water with moderate concentration of heavy metals. The pond water occasionally showed toxic effects but no correlation between heavy metals and toxicity was identified. PAHs concentrations were...... for both catchments low and no correlations between PAH concentrations in the pond and toxicity were found....

  15. Gas transfer velocities in small forested ponds

    Science.gov (United States)

    Holgerson, Meredith A.; Farr, Emily R.; Raymond, Peter A.

    2017-05-01

    Inland waters actively exchange gases with the atmosphere, and the gas exchange rate informs system biogeochemistry, ecology, and global carbon budgets. Gas exchange in medium- to large-sized lakes is largely regulated by wind; yet less is known about processes regulating gas transfer in small ponds where wind speeds are low. In this study, we determined the gas transfer velocity, k600, in four small (water temperature; however, the explanatory power was weak (R2 water bodies, we compiled direct measurements of k600 from 67 ponds and lakes worldwide. Our k600 estimates were within the range of estimates for other small ponds, and variability in k600 increased with lake size. However, the majority of studies were conducted on medium-sized lakes (0.01 to 1 km2), leaving small ponds and large lakes understudied. Overall, this study adds four small ponds to the existing body of research on gas transfer velocities from inland waters and highlights uncertainty in k600, with implications for calculating metabolism and carbon emissions in inland waters.

  16. Light and electron microscopic localization of GABAA-receptors on cultured cerebellar granule cells and astrocytes using immunohistochemical techniques

    DEFF Research Database (Denmark)

    Hansen, Gert Helge; Hösli, E; Belhage, B

    1991-01-01

    . At the light microscope level specific staining of GABAA-receptors was localized in various types of neurones in explant cultures of rat cerebellum using the indirect peroxidase-antiperoxidase (PAP) technique, whereas no specific staining was found in astrocytes. At the electron microscope level labeling...... of GABAA-receptors was observed in the plasma membrane of both the cell bodies and processes in dissociated primary cultures of cerebellar granule cells using an indirect preembedding immunogold staining technique which in contrast to the classical PAP technique allows quantitative estimations...

  17. Event-based stormwater management pond runoff temperature model

    Science.gov (United States)

    Sabouri, F.; Gharabaghi, B.; Sattar, A. M. A.; Thompson, A. M.

    2016-09-01

    Stormwater management wet ponds are generally very shallow and hence can significantly increase (about 5.4 °C on average in this study) runoff temperatures in summer months, which adversely affects receiving urban stream ecosystems. This study uses gene expression programming (GEP) and artificial neural networks (ANN) modeling techniques to advance our knowledge of the key factors governing thermal enrichment effects of stormwater ponds. The models developed in this study build upon and compliment the ANN model developed by Sabouri et al. (2013) that predicts the catchment event mean runoff temperature entering the pond as a function of event climatic and catchment characteristic parameters. The key factors that control pond outlet runoff temperature, include: (1) Upland Catchment Parameters (catchment drainage area and event mean runoff temperature inflow to the pond); (2) Climatic Parameters (rainfall depth, event mean air temperature, and pond initial water temperature); and (3) Pond Design Parameters (pond length-to-width ratio, pond surface area, pond average depth, and pond outlet depth). We used monitoring data for three summers from 2009 to 2011 in four stormwater management ponds, located in the cities of Guelph and Kitchener, Ontario, Canada to develop the models. The prediction uncertainties of the developed ANN and GEP models for the case study sites are around 0.4% and 1.7% of the median value. Sensitivity analysis of the trained models indicates that the thermal enrichment of the pond outlet runoff is inversely proportional to pond length-to-width ratio, pond outlet depth, and directly proportional to event runoff volume, event mean pond inflow runoff temperature, and pond initial water temperature.

  18. Solar radiation absorption in solar ponds

    Energy Technology Data Exchange (ETDEWEB)

    Cengel, Y.A.; Ozisik, M.N.

    1984-01-01

    The local rate of absorption of the solar radiation in a solar pond is determined for the direct component at angles of incidence from 0/sup 0/ to 75/sup 0/ with 15/sup 0/ intervals as well as for the diffuse component by the exact treatment of the radiation problem. The effects of bottom reflection, the pond depth, the type of radiation on the thermal performance of the pond are examined, and a new rigorous approach is presented for treating diffuse radiation as a direct beam. The fraction of the solar radiation absorbed within the first 10 cm of water is determined under various conditions. The local rate of solar energy absorption at any depth and at any incidence angle can readily be computed from a fourthdegree polynomial expression, the coefficients of which are tabulated for different incidence angles and bottom reflectivities.

  19. Salt Ponds, South San Francisco Bay

    Science.gov (United States)

    2002-01-01

    higher resolution 1000 pixel-wide image The red and green colors of the salt ponds in South San Francisco Bay are brilliant visual markers for astronauts. The STS-111 crew photographed the bay south of the San Mateo bridge in June, 2002. This photograph is timely because a large number of the salt ponds (more than 16,500 acres) that are owned by Cargill, Inc. will be sold in September for wetlands restoration-a restoration project second in size only to the Florida Everglades project. Rough boundaries of the areas to be restored are outlined on the image. Over the past century, more than 80% of San Francisco Bay's wetlands have been filled and developed or diked off for salt mining. San Francisco Bay has supported salt mining since 1854. Cargill has operated most of the bay's commercial salt ponds since 1978, and had already sold thousands of acres to the State of California and the Don Edwards National Wildlife Refuge. This new transaction will increase San Francisco Bay's existing tidal wetlands by 50%. The new wetlands, to be managed by the California Department of Fish and Game and the U.S. Fish and Wildlife Service, will join the Don Edwards National Wildlife Refuge, and provide valuable habitat for birds, fish and other wildlife. The wetlands will contribute to better water quality and flood control in the bay, and open up more coastline for public enjoyment. Additional information: Cargill Salt Ponds (PDF) Turning Salt Into Environmental Gold Salt Ponds on Way to Becoming Wetlands Historic Agreement Reached to Purchase San Francisco Bay Salt Ponds Astronaut photograph STS111-376-3 was provided by the Earth Sciences and Image Analysis Laboratory at Johnson Space Center. Additional images taken by astronauts and cosmonauts can be viewed at the NASA-JSC Gateway to Astronaut Photography of Earth

  20. Valuing Multiple Benefits, and the Public Perception of SUDS Ponds

    Directory of Open Access Journals (Sweden)

    Joy Jarvie

    2017-02-01

    Full Text Available Understanding how the public perceive and value ponds is fundamental to appreciate the synergy between Sustainable urban Drainage (SUDS ponds and the multiple benefits they provide. This paper investigates this, through the application of a structured postal and online survey, for a case study area of Edinburgh, in the UK. It compares man-made ponds (including SUDS, and ponds with natural origins. The results from Whole Life Cost show that the benefits (based on Contingent Valuation exceed the CAPEX and OPEX costs for three of five artificial ponds studied. Benefits from natural (reference ponds exceed the replacement costs for a pond with the same surface area/catchment. This paper highlights the importance of monetising the multiple benefits from ponds.

  1. Sea Ice Melt Pond Data from the Canadian Arctic

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains observations of albedo, depth, and physical characteristics of melt ponds on sea ice, taken during the summer of 1994. The melt ponds studied...

  2. Fate of Pyrethroids in Farmland Ponds

    DEFF Research Database (Denmark)

    Mogensen, B. B.; Sørensen, P. B.; Stuer-Lauridsen, F.;

    Pyrethroids constitute a group of widely used insecticides, which are toxic to aquatic organisms. This report presents the results from a 2-year study of the fate of pyrethroids in ponds, i.e. their distribution in the water column, the sediment and the surface microlayer respectively. The measur......Pyrethroids constitute a group of widely used insecticides, which are toxic to aquatic organisms. This report presents the results from a 2-year study of the fate of pyrethroids in ponds, i.e. their distribution in the water column, the sediment and the surface microlayer respectively...

  3. Pond dyes are Culex mosquito oviposition attractants

    Directory of Open Access Journals (Sweden)

    Natali Ortiz Perea

    2017-05-01

    Full Text Available Background British mosquito population distribution, abundance, species composition and potential for mosquito disease transmission are intimately linked to the physical environment. The presence of ponds and water storage can significantly increase the density of particular mosquito species in the garden. Culex pipiens is the mosquito most commonly found in UK gardens and a potential vector of West Nile Virus WNV, although the current risk of transmission is low. However any factors that significantly change the distribution and population of C. pipiens are likely to impact subsequent risk of disease transmission. Pond dyes are used to control algal growth and improve aesthetics of still water reflecting surrounding planting. However, it is well documented that females of some species of mosquito prefer to lay eggs in dark water and/or containers of different colours and we predict that dyed ponds will be attractive to Culex mosquitoes. Methods Black pond dye was used in oviposition choice tests using wild-caught gravid C. pipiens. Larvae from wild-caught C. pipiens were also reared in the pond dye to determine whether it had any impact on survival. An emergence trap caught any adults that emerged from the water. Water butts (80 L were positioned around university glasshouses and woodland and treated with black pond dye or left undyed. Weekly sampling over a six month period through summer and autumn was performed to quantified numbers of larvae and pupae in each treatment and habitat. Results Gravid female Culex mosquitoes preferred to lay eggs in dyed water. This was highly significant in tests conducted under laboratory conditions and in a semi-field choice test. Despite this, survivorship in black dyed water was significantly reduced compared to undyed water. Seasonal analysis of wild larval and pupal numbers in two habitats with and without dye showed no impact of dye but a significant impact of season and habitat. Mosquitoes were more

  4. Impact of pond and fence aquaculture on reservoir environment

    Directory of Open Access Journals (Sweden)

    Huai-dong ZHOU

    2011-03-01

    Full Text Available With the rapid development of aquaculture in lakes and reservoirs, its negative effects on water quality and aquatic organisms are clearly emerging. Toward a better understanding of these effects, chemical and biological monitoring was conducted in the Fangbian Reservoir to study the relationship between aquaculture and eutrophication. As a domestic water supply source, this reservoir has reached the mesotrophic level. The concentrations of total nitrogen (TN and total phosphorus (TP in the Fangbian Reservoir have frequently exceeded the prescriptive level according to the Environmental Quality Standards for Surface Water (GB3838-2002. Pond and fence aquaculture feeding is the main cause of high levels of nitrogen and phosphorus, accounting for nearly half of the total pollution, and causing the reservoir environmental capacity to be exceeded. The amounts of nitrogen and phosphorus that went directly to the reservoir through the residual bait and fish droppings in fence aquaculture were 42 768 kg per year and 10 856 kg per year respectively, from 2007 to 2009. About 2 913 kg of nitrogen and 450 kg of phosphorus were imported to the reservoir through the exchange of water from the culturing ponds at the same time. Therefore, controlling the aquaculture scale and promoting eco-aquaculture are key measures for lessening the eutrophication degree and improving the water quality.

  5. Bacterial infection of mudfish Clarias gariepinus (Siluriformes: Clariidae) fingerlings in tropical nursery ponds.

    Science.gov (United States)

    Ikpi, Gabriel; Offem, Benedict

    2011-06-01

    Bacterial infection among the most common cultured mudfish Clarias gariepinus in Africa, has become a cause of concern, because it constitutes the largest economic loss in fish farms. In order to provide useful biological data of the pathogens for good management practices, samples were collected monthly between January 2008 and December 2009 in three monoculture nursery ponds, located in three different positions: upriver (A, grassland), mid-river (B, mixed forest and grassland) and downriver (C, rainforest) along 200 km length of Cross River floodplains, Nigeria. A total of 720 fingerlings between 15.1 and 20.7 g were analyzed to determine the degree of infection. The bacterial pathogens were taken from their external surfaces, and were isolated and identified by standard methods. The caudal fins of fingerlings from pond A had the highest bacterial load (5.8 x 10(3) cfu/g), while the least counts (1.2 x 103 cfu/g) were identified on the head of fish from pond C, with Flexibacter columnaris as the major etiological agent. Pseudomonas fluorescens, Aeromonas hydrophila, Escherichia coli, Staphylococcus aureus and Micrococcus luteus were identified as co-isolates with P. fluorescens as dominant (0.7 x 10(2) cfu/mL) co-isolates in pond water. Clinical signs of five white spots with red periphery appeared on the external surface of infected fish. All the fish sampled, died after 4 to 9 days. There was no significant difference in the bacterial counts between different ponds, but the difference between fish organs/parts examined was significant. Fish from these ponds are therefore potentially dangerous to consumers and highly devalued, with the economic impact to producers. Preventive methods to avoid these infections are recommended.

  6. Ecological impacts of fluridone and copper sulphate in catfish aquaculture ponds.

    Science.gov (United States)

    Jacob, Annie P; Culver, David A; Lanno, Roman P; Voigt, Astrid

    2016-05-01

    Fluridone and copper sulphate are often used for controlling macrophytes and algae in aquaculture ponds. The present study examined the ecological effects of these chemicals on macrophyte, phytoplankton, and zooplankton biomass; plankton community structure; water quality parameters; and fish survival and yield in catfish culture ponds using a randomized complete block design. The estimated half-life of fluridone in the individual ponds ranged from 1.6 d to 10.8 d. Free copper ion activity in ponds treated with copper sulphate was dynamic, ranging from pCu of 7.7 to 8.9 after each application and decreasing to approximately 12 (1 × 10(-12)  M) within 1 wk after each application, approaching observed values in control ponds (pCu = 12.3-13.4). No difference in macrophyte biomass was observed among treatments. Fluridone and copper treatments elicited different responses within the phytoplankton community. Copper treatments reduced Cyanophyta biomass but increased biomass of more tolerant taxa among the Chlorophyta and Chrysophyta. Fluridone treatments reduced total phytoplankton biomass including Cyanophyta and increased the sensitivity of Chlorophyta and Chrysophyta to copper. Copper also affected zooplankton community composition as a result of direct toxic effects on sensitive zooplankton taxa (e.g., Cladocera), whereas Copepoda biomass in copper-treated ponds exceeded that in controls. Catfish survival and yield were not significantly different among treatments. The results of the present study suggest that fluridone and copper interact at realistic application rates, increasing the ability to control algae compared with treatments where they are applied alone.

  7. Nat'l_Register, ContributingResources, The Ponds at Pipe Spring National Monument, Arizona (pisp_ponds)

    Data.gov (United States)

    National Park Service, Department of the Interior — This is an Arc/Info coverage consisting of 2 polygons representing the ponds at Pipe Spring National Monument, Arizona. The ponds were collected by a Trimble GeoXT...

  8. Fatty Acids as a Tool to Understand Microbial Diversity and Their Role in Food Webs of Mediterranean Temporary Ponds

    Directory of Open Access Journals (Sweden)

    Carla C. C. R. de Carvalho

    2014-04-01

    Full Text Available Temporary Mediterranean ponds are complex ecosystems which support a high diversity of organisms that include heterotrophic microorganisms, algae, crustaceans, amphibians and higher plants, and have the potential to supply food and a resting place to migratory birds. The role of heterotrophs at the base of the food web in providing energy to the higher trophic levels was studied in temporary ponds in Central and Southern Portugal. The relative quantification of the hetero and autotrophic biomass at the base of the food web in each pond was derived from the polar fatty acid (PLFA composition of seston through the application of the matrix factorization program CHEMTAX that used specific PLFA and their relative proportion as markers for e.g., classes of bacteria, algae and fungi. The species composition of the culturable microbial communities was identified through their fatty acid profiles. The biomass in the lower trophic level of some ponds presented an even proportion of auto to heterotrophic organisms whilst either bacteria or algae dominated in others. In a selected subset of ponds, the incorporation of bacterial fatty acids was observed to occur in potentially herbivorous zooplankton crustacean. Zooplankton consumed and incorporated bacterial fatty acids into their body tissues, including into their phospholipids, which indicates that energy of heterotrophic origin contributes to the aquatic food webs of temporary ponds.

  9. Molecular diversity of the methanotrophic bacteria communities associated with disused tin-mining ponds in Kampar, Perak, Malaysia.

    Science.gov (United States)

    Sow, S L S; Khoo, G; Chong, L K; Smith, T J; Harrison, P L; Ong, H K A

    2014-10-01

    In a previous study, notable differences of several physicochemical properties, as well as the community structure of ammonia oxidizing bacteria as judged by 16S rRNA gene analysis, were observed among several disused tin-mining ponds located in the town of Kampar, Malaysia. These variations were associated with the presence of aquatic vegetation as well as past secondary activities that occurred at the ponds. Here, methane oxidizing bacteria (MOB), which are direct participants in the nutrient cycles of aquatic environments and biological indicators of environmental variations, have been characterised via analysis of pmoA functional genes in the same environments. The MOB communities associated with disused tin-mining ponds that were exposed to varying secondary activities were examined in comparison to those in ponds that were left to nature. Comparing the sequence and phylogenetic analysis of the pmoA clone libraries at the different ponds (idle, lotus-cultivated and post-aquaculture), we found pmoA genes indicating the presence of type I and type II MOB at all study sites, but type Ib sequences affiliated with the Methylococcus/Methylocaldum lineage were most ubiquitous (46.7 % of clones). Based on rarefaction analysis and diversity indices, the disused mining pond with lotus culture was observed to harbor the highest richness of MOB. However, varying secondary activity or sample type did not show a strong variation in community patterns as compared to the ammonia oxidizers in our previous study.

  10. 粤西凡纳滨对虾海水滩涂养殖池塘浮游微藻群落结构特征%Structure characteristics of planktonic microalgae community in Litopenaeus vannamei shoal water culture ponds in western Guangdong

    Institute of Scientific and Technical Information of China (English)

    彭聪聪; 李卓佳; 曹煜成; 刘孝竹; 胡晓娟

    2011-01-01

    Planktonic microalgae in shrimp ponds play the role of primary producers, and have a major impact on material cycle and energy supply of the water ecosystem. The continual and regular surveys on the planktonic microalgae community were conducted in four Litopenae-us vannamai shoal water culture ponds at Guanlida Biotechnology Corporation in Dianbai, Maoming, Guangdong Province. Moreover, the community compositions of planktonic microalgae in shrimp ponds and their characteristics were analyzed. The results showed that a total of 91 planktonic microalgae species were identified during the culture period. Among them, 30 species were Cyanophyta, 15 were Chlorophyta, 37 were Bacillariophyta, 5 were Pyrrophyta, 2 were Euglenophyta, and 2 were Chrysophyceae. The dominant species were Arthrospira plat ensis , Chlorella pyrenoidosa , Kirchneriella microscopica , Peridinium pusillum, Nitzschia closterium, Lyngbya gardneri, Oscillatoria chlorina , Oscillatoria salina , Nostoc microscopi-cum , Oscillatoria neglecta , and Oscillatoria willei. During the early culture period, the range of the quantities of planktonic microalgae, the biomass and the diversity index averages were 5. 12×10-4~95. 41×104ind/L, 1. 95~1. 18 × 102μg/L, and 0. 84 ~ 2. 16, respectively. Chloro phyta and Bacillariophyta often appeared. However, in the middle and final phases, the averag esplanktonic microalgae density, the averages of biomass and the diversity index ranged in 66. 11×104~1.28×109ind/L, 13. 3~ 11. 87×103μg/L> and 1.64 ~2.87 respectively, and Oscil latoria gradually became the dominant species. The present study demonstrated that all the planktonic microalgae density, biomass and diversity index showed the same trend that they were generally low at the initial phase of the culture period and became high at the final phase. However, in mid-late July, the planktonic microalgae density and the physical and chemical fac tors in water fluctuated under the influence of severe weather

  11. Temporal Eukarya, Bacteria, and Archaea biodiversity during cultivation of an alkaliphilic algae, Chlorella vulgaris, in an outdoor raceway pond

    Directory of Open Access Journals (Sweden)

    Tisza Ann Szeremy Bell

    2016-01-01

    Full Text Available Algal biofuels and valuable co-products are being produced in both open and closed cultivation systems. Growing algae in open pond systems may be a more economical alternative, but this approach allows environmental microorganisms to colonize the pond and potentially infect or outcompete the algal crop. In this study, we monitored the microbial community of an outdoor, open raceway pond inoculated with a high lipid-producing alkaliphilic alga, Chlorella vulgaris BA050. The strain C. vulgaris BA050 was previously isolated from Soap Lake, Washington, a system characterized by a high pH (approximately 9.8. An outdoor raceway pond (200L was inoculated with C. vulgaris and monitored for ten days and then the culture was transferred to a 2,000L raceway pond and cultivated for an additional six days. Community DNA samples were collected over the 16-day period in conjunction with water chemistry analyses and cell counts. Universal primers for the SSU rRNA gene sequences for Eukarya, Bacteria, and Archaea were used for barcoded pyrosequence determination. The environmental parameters that most closely correlated with C. vulgaris abundance were pH and phosphate. Community analyses indicated that the pond system remained dominated by the Chlorella population (93% of eukaryotic sequences, but was also colonized by other microorganisms. Bacterial sequence diversity increased over time while archaeal sequence diversity declined over the same time period. Using SparCC co-occurrence network analysis, a positive correlation was observed between C. vulgaris and Pseudomonas sp. throughout the experiment, which may suggest a symbiotic relationship between the two organisms. The putative relationship coupled with high pH may have contributed to the success of C. vulgaris. The characterization of the microbial community dynamics of an alkaliphilic open pond system provides significant insight into open pond systems that could be used to control photoautotrophic

  12. Aquatic Habitats: Exploring Desktop Ponds. Teacher's Guide.

    Science.gov (United States)

    Barrett, Katharine; Willard, Carolyn

    This book, for grades 2-6, is designed to provide students with a highly motivating and unique opportunity to investigate an aquatic habitat. Students set up, observe, study, and reflect upon their own "desktop ponds." Accessible plants and small animals used in these activities include Elodea, Tubifex worms, snails, mosquito larvae, and fish.…

  13. Evaluation of power consumption of paddle wheel in an open raceway pond.

    Science.gov (United States)

    Li, Yanxi; Zhang, Qinghua; Wang, Zhihui; Wu, Xia; Cong, Wei

    2014-07-01

    Open raceway ponds are widely adopted in microalgae cultivation. Paddle wheels consume the most part of power during the process of cultivation in open raceway ponds. The configuration of blades directly determines power consumption for paddle wheels. In this work, power consumption of four blades configurations was determined in a bench-scale open raceway pond of 2.2 m(2). The effect of blades configuration, the influence of filling levels from 5 to 15 cm and influence of rotational speeds from 7 to 15 r min(-1) on shaft power consumption (P(S)), fluid velocity (U(c)) and paddle wheel efficiency (η) was investigated. Results demonstrated that flat blades were the most efficient configuration. Higher culture depth led to larger U(c), more P(s) and larger η, especially when blades were not totally immerged in water. Under the same filling level and rotational speed, the value of P(S) decreases in the order: zigzagged, flat, forward-curved and back-curved, respectively. The zigzagged blades led to a larger U(c) at the culture depth of 5 cm, while flat and forward-curved blades drove a larger U(c) when culture depth was higher than 5 cm. The maximum value of η was 0.50 with flat blades at 11 r min(-1) and 15 cm of culture depth. Empirical correlations of non-dimensional numbers related to operation parameters and blades geometry for four paddle wheel blades were also proposed.

  14. Growth performance and gonadal development of pond-reared Chi-nese mitten crab (Eriocheir sinensis) fed formulated diets during the whole culture process%全程投喂配合饲料条件下池养中华绒螯蟹的生长性能及其性腺发育

    Institute of Scientific and Technical Information of China (English)

    何杰; 吴旭干; 赵恒亮; 姜晓东; 葛永春; 王幼鹏; 成永旭

    2016-01-01

    Formulated diets are an important factor in the sustainable development ofEriocheir sinensisaquacul-ture. However, no information is available on the growth performance or gonadal development ofE. sinensis based on the formulated diets they are fed in pond culture. Therefore, in this study, we investigated the growth perform-ance, survival, precocity rate of first-year crabs, gonadal development of second-year crabs, crab yield, size dis-tribution, and feed conversion rate (FCR) ofE. sinensis during the first and second years of pond culture when fed formulated diets. (1) During the whole juvenile crab culture stage (first year), no significant difference was de-tected in the growth performance of males and females, the average specific growth rate (SGR) was about 1.9%/d, and growth was rapid from June to September; the mean survival and precocity rates were around 10.0% and 4.9%, respectively, and females had significantly higher precocity rates than males; at the end of the first year of culture, the bodyweights of the precocious crabs and normal juveniles were around 19.8 g and 7.5 g, respectively, whereas the average yields of precocious crabs and normal juveniles were 229 kg/hm2 and 2433 kg/hm2, respectively; die-tary consumption mainly occurred between July and October, which accounted for more than 80% of the total feed consumption, and the feed consumption was related to the crab biomass and water temperature; FCR was around 2.15 for the whole juvenile culture period. (2) During the whole adult crab culture stage (second year), the average SGRs of the female and male crabs were about 1.6%/d and 1.4%/d, respectively, and the males grew faster than the females after June; the final mean body weights of the adult males and females were around 126 g and 181 g, re-spectively; the survival rates of the females and males were 61.30% and 53.47%, respectively, and the overall sur-vival was 58.4%, whereas the yields were around 412.20 kg/hm2 (females), 536.10 kg/hm2

  15. A screening model to predict microalgae biomass growth in photobioreactors and raceway ponds.

    Science.gov (United States)

    Huesemann, M H; Van Wagenen, J; Miller, T; Chavis, A; Hobbs, S; Crowe, B

    2013-06-01

    A microalgae biomass growth model was developed for screening novel strains for their potential to exhibit high biomass productivities under nutrient-replete conditions in photobioreactors or outdoor ponds. Growth is modeled by first estimating the light attenuation by biomass according to Beer-Lambert's Law, and then calculating the specific growth rate in discretized culture volume slices that receive declining light intensities due to attenuation. The model uses only two physical and two species-specific biological input parameters, all of which are relatively easy to determine: incident light intensity, culture depth, as well as the biomass light absorption coefficient and the specific growth rate as a function of light intensity. Roux bottle culture experiments were performed with Nannochloropsis salina at constant temperature (23°C) at six different incident light intensities (10, 25, 50, 100, 250, and 850 µmol/m(2)  s) to determine both the specific growth rate under non-shading conditions and the biomass light absorption coefficient as a function of light intensity. The model was successful in predicting the biomass growth rate in these Roux bottle batch cultures during the light-limited linear phase at different incident light intensities. Model predictions were moderately sensitive to minor variations in the values of input parameters. The model was also successful in predicting the growth performance of Chlorella sp. cultured in LED-lighted 800 L raceway ponds operated in batch mode at constant temperature (30°C) and constant light intensity (1,650 µmol/m(2)  s). Measurements of oxygen concentrations as a function of time demonstrated that following exposure to darkness, it takes at least 5 s for cells to initiate dark respiration. As a result, biomass loss due to dark respiration in the aphotic zone of a culture is unlikely to occur in highly mixed small-scale photobioreactors where cells move rapidly in and out of the light. By contrast

  16. A Screening Model to Predict Microalgae Biomass Growth in Photobioreactors and Raceway Ponds

    Energy Technology Data Exchange (ETDEWEB)

    Huesemann, Michael H.; Van Wagenen, Jonathan M.; Miller, Tyler W.; Chavis, Aaron R.; Hobbs, Watts B.; Crowe, Braden J.

    2013-06-01

    A microalgae biomass growth model was developed for screening novel strains for their potential to exhibit high biomass productivities under nutrient-replete conditions in photobioreactors or outdoor ponds. Growth is modeled by first estimating the light attenuation by biomass according to Beer-Lambert’s law, and then calculating the specific growth rate in discretized culture volume slices that receive declining light intensities due to attenuation. The model requires only two physical and two species-specific biological input parameters, all of which are relatively easy to determine: incident light intensity, culture depth, as well as the biomass light absorption coefficient and the specific growth rate as a function of light intensity. Roux bottle culture experiments were performed with Nannochloropsis salina at constant temperature (23 °C) at six different incident light intensities (5, 10, 25, 50, 100, 250, and 850 μmol/m2∙ sec) to determine both the specific growth rate under non-shading conditions and the biomass light absorption coefficient as a function of light intensity. The model was successful in predicting the biomass growth rate in these Roux bottle cultures during the light-limited linear phase at different incident light intensities. Model predictions were moderately sensitive to minor variations in the values of input parameters. The model was also successful in predicting the growth performance of Chlorella sp. cultured in LED-lighted 800 L raceway ponds operated at constant temperature (30 °C) and constant light intensity (1650 μmol/m2∙ sec). Measurements of oxygen concentrations as a function of time demonstrated that following exposure to darkness, it takes at least 5 seconds for cells to initiate dark respiration. As a result, biomass loss due to dark respiration in the aphotic zone of a culture is unlikely to occur in highly mixed small-scale photobioreactors where cells move rapidly in and out of the light. By contrast, as

  17. Temporal variation in the water quality of ponds and effluent of grow-out ponds of Amazon River prawn Macrobrachium amazonicum

    Directory of Open Access Journals (Sweden)

    Erlei Cassiano Keppeler

    2013-06-01

    Full Text Available This study was conducted in the Crustacean Sector of the Aquaculture Center (CAUNESP at the São Paulo State University, Jaboticabal (21 ° 15’22”S and 48 ° 18’48”W São Paulo, Brazil, from December 2003 to May 2004. The aim was to examine the water quality parameters of importance to freshwater prawn culture, operated in a semi-intensive system in Amazon River. Nine 0.01-ha earthen ponds were stocked with 20 juveniles.m -2 . Prawns were fed commercial diet at a rate of 7 to 9% of biomass until the 14th week. After 145 days of stocking, all ponds were drained and harvested. The following water parameters were determined weekly: dissolved oxygen, oxygen biochemical demand, pH, total alkalinity, electrical conductivity, suspended total solids and turbidity, N-nitrate, N-nitrite, N-nitrogen ammonia, N- total, soluble ortophosphate, total phosphorus, chlorophyll and pheophytin. In the semi-intensive culture system of M. amazonicum, there was no clear pattern of temporal variation in the limnological variables studied. Dissolved oxygen, pH, BOD, ammonia nitrogen and nitrate increased in the afternoon period while, the other variables did not change. In general, water quality is more dependent on the biological processes that occur in the pond than on the characteristics of the renewal water for some variable.

  18. O2 evolution and cyclic electron flow around photosystem I in long-term ground batch culture of Euglena gracilis

    Science.gov (United States)

    An, Yanjun; Wang, Suqin; Hao, Zongjie; Zhou, Yiyong; Liu, Yongding

    2014-12-01

    Based on the purpose of better exploring the function of green producers in the closed aquatic biological life support system, the condition of dynamic O2 evolution and performance of cyclic electron flow around photosystem I (CEF-PSI) in long-term ground batch culture of Euglena gracilis were studied, the relationship between linear electron flow (LEF) and CEF-PSI was revealed, the function of CEF-PSI was investigated. Excellent consistency in O2 evolution pattern was observed in cultures grown in both closed and open containers, O2 evolution was strictly suppressed in phase 1, but the rate of it increased significantly in phase 2. CEF-PSI was proposed to be active during the whole course of cultivation, even in the declining phase 3, it still operated at the extent of 47-55%. It is suggested that the relationship between LEF and CEF-PSI is not only competition but also reciprocity. CEF-PSI was proposed to contribute to the considerable growth in phase 1; it was also suggested to play an important protective role against photosystem II (PSII) photoinhibition at the greatly enhanced level (approximately 80-95%) on the 2nd day. Our results in this research suggest that E. gracilis had very particular photosynthetic characteristics, the strict O2 evolution suppression in the initial culture phase might be a special light acclimation behavior, and CEF-PSI could be an important mechanism involved in this kind of adaptation to the changeable light environment.

  19. Mixed-genotype white spot syndrome virus infections of shrimp are inversely correlated with disease outbreaks in ponds.

    Science.gov (United States)

    Hoa, Tran Thi Tuyet; Zwart, Mark P; Phuong, Nguyen T; Oanh, Dang T H; de Jong, Mart C M; Vlak, Just M

    2011-03-01

    Outbreaks of white spot syndrome virus (WSSV) in shrimp culture and the relationship between the virus and virulence are not well understood. Here, we provide evidence showing that WSSV mixed-genotype infections correlate with lower outbreak incidence and that disease outbreaks correlate with single-genotype infections. We tested 573 shrimp samples from 81 shrimp ponds in the Mekong delta with outbreak or non-outbreak status. The variable number tandem repeat (VNTR) loci of WSSV were used as molecular markers for the characterization of single- and mixed-genotype infections. The overall prevalence of mixed-genotype WSSV infections was 25.7 %. Non-outbreak ponds had a significantly higher frequency of mixed-genotype infections than outbreak ponds for all VNTR loci, both at the individual shrimp as well as at the pond level. The genetic composition of WSSV populations appears to correlate with the health status of shrimp culture in ponds. The causal relationship between genotypic diversity and disease outbreaks can now be experimentally approached.

  20. EVALUATING THE ECOLOGICAL RESILIENT DRIVEN PERFORMANCE OF A TROPICAL WASTE STABILIZATION POND SYSTEM USING ECOLOGICAL SIGNATURE OF BIOLOGICAL INTEGRITY

    Directory of Open Access Journals (Sweden)

    Susmita Lahiri Ganguly

    2015-06-01

    Full Text Available Using ecological signature of biological integrity as a measure of performance, the reclamation efficiency of waste stabilization ponds was evaluated over a period of four years in a tropical sewage treatment plant – cum fish culture consisting of two anaerobic, two facultative and four maturation ponds located serially across the sewage effluent gradient. The four maturation ponds were used for batch culture of fish. Samples of surface and bottom water as well as surface sediment were collected twice a month from different ponds of the system and examined for some nutrient cycling bacteria, primary production, chlorophyll content of micro-algae, phytoplankton, zooplankton abundance, fish growth and water quality parameters. Computation of ecological signature using aerobic mineralization index for heterotrophic and ammonifying bacteria revealed steady increase across the sewage effluent gradient. The heterotrophic and ammonifying bacterial populations appeared to have a direct function with the concentrations of chemical oxygen demand of water. The sum of total scores for different optimal conditions for fish growth increased as a function of the distance from the source of effluent implying that ecological resilience of the waste stabilization ponds has been accomplished by the sedimentation, chelation, and biological functional attributes mediated through redundancy of different subsystems, self- purification capacity of the system as a whole.

  1. Microbial activities and communities in oil sands tailings ponds

    Energy Technology Data Exchange (ETDEWEB)

    Gieg, Lisa; Ramos, Esther; Clothier, Lindsay; Bordenave, Sylvain; Lin, Shiping; Voordouw, Gerrit; Dong, Xiaoli; Sensen, Christoph [University of Calgary (Canada)

    2011-07-01

    This paper discusses how the microbial communities and their activity play a vital role in tailings ponds. The ponds contain microorganisms along with metals, hydrocarbon diluent, naphthenic acid and others. The ponds play an important role in mining operations because they store bitumen extraction waste and also allow water to be re-used in the bitumen extraction process. Pond management presents a few challenges that include, among others, gas emissions and the presence of toxic and corrosive acids. Microbial activities and communities help in managing these ponds. Microbial activity measurement in active and inactive ponds is described and analyzed and the results are presented. The conditions for reducing sulfate, nitrate and iron are also presented. From the results it can be concluded that naphthenic acids can potentially serve as substrates for anaerobic populations in tailings ponds.

  2. Heavy metals, PAHs and toxicity in stormwater wet detention ponds

    DEFF Research Database (Denmark)

    Wium-Andersen, Tove; Nielsen, Asbjørn Haaning; Hvitved-Jacobsen, Thorkild

    2011-01-01

    Concentrations of 6 different heavy metals and total Polycyclic Aromatic Hydrocarbons (PAH) were determined in stormwater runoff and in the pond water of two Danish wet detention ponds. The pond water samples were analyzed for toxic effects, using the algae Selenastrum capricornutum as a test...... organism. Stormwater and pond water from a catchment with light industry showed high levels of heavy metals, especially zinc and copper. The pond water showed high toxic effects and copper were found to be the main toxicant. Additionally, a large part of the copper was suspected to be complex bound......, reducing the potential toxicity of the metal. Another catchment (residential) produced stormwater and pond water with moderate concentration of heavy metals. The pond water occasionally showed toxic effects but no correlation between heavy metals and toxicity was identified. PAHs concentrations were...

  3. cultural

    Directory of Open Access Journals (Sweden)

    Irene Kreutz

    2006-01-01

    Full Text Available Es un estudio cualitativo que adoptó como referencial teorico-motodológico la antropología y la etnografía. Presenta las experiencias vivenciadas por mujeres de una comunidad en el proceso salud-enfermedad, con el objetivo de comprender los determinantes sócio-culturales e históricos de las prácticas de prevención y tratamiento adoptados por el grupo cultural por medio de la entrevista semi-estructurada. Los temas que emergieron fueron: la relación entre la alimentación y lo proceso salud-enfermedad, las relaciones con el sistema de salud oficial y el proceso salud-enfermedad y lo sobrenatural. Los dados revelaron que los moradores de la comunidad investigada tienen un modo particular de explicar sus procedimientos terapéuticos. Consideramos que es papel de los profesionales de la salud en sus prácticas, la adopción de abordajes o enfoques que consideren al individuo en su dimensión sócio-cultural e histórica, considerando la enorme diversidad cultural en nuestro país.

  4. Effect of pond water depth on snail populations and fish-borne zoonotic trematode transmission in juvenile giant gourami (Osphronemus goramy) aquaculture nurseries.

    Science.gov (United States)

    Thien, P C; Madsen, H; Nga, H T N; Dalsgaard, A; Murrell, K D

    2015-12-01

    Infection with fish-borne zoonotic trematodes (FZT) is an important public health problem in many parts of Southeast Asia. People become infected with FZT when eating raw or undercooked fish that contain the infective stage (metacercariae) of FZT. The parasites require specific freshwater snails as first intermediate host and a variety of fish species, both wild caught and cultured, as second intermediate host. Aquaculture production has grown almost exponentially in SE Asia and in order to produce fish free from FZT metacercariae, it is important to mitigate factors promoting transmission to fish. Here we report results from a cross-sectional study to look at the association between pond depth and infection with FZT in giant gourami nursery ponds. Density of intermediate host snails was positively associated with pond depth (count ratio associated with a 1m increase in pond depth was 10.4 (95% C.L.: 1.61-67.1, p200 fry m(-3)) was associated with lower host snail density (count ratio=0.15) than low stocking density (<100 fry m(3)). Ponds stocked with 100-200 fry m(-3) had snail counts 0.76 (95% C.L.: 0.33-1.75, p n.s.) of those in ponds stocked with fry density of <100 fry m(-3). Since density of intermediate snail hosts was associated with FZT transmission to fish, effort should be taken to reduce snail density prior to stocking the fry, but focus should also be on habitats surrounding ponds as transmission may occur through cercariae produced outside ponds and carried into ponds with water pumped into ponds.

  5. Urban ponds as an aquatic biodiversity resource in modified landscapes.

    Science.gov (United States)

    Hill, Matthew J; Biggs, Jeremy; Thornhill, Ian; Briers, Robert A; Gledhill, David G; White, James C; Wood, Paul J; Hassall, Christopher

    2017-03-01

    Urbanization is a global process contributing to the loss and fragmentation of natural habitats. Many studies have focused on the biological response of terrestrial taxa and habitats to urbanization. However, little is known regarding the consequences of urbanization on freshwater habitats, especially small lentic systems. In this study, we examined aquatic macro-invertebrate diversity (family and species level) and variation in community composition between 240 urban and 782 nonurban ponds distributed across the United Kingdom. Contrary to predictions, urban ponds supported similar numbers of invertebrate species and families compared to nonurban ponds. Similar gamma diversity was found between the two groups at both family and species taxonomic levels. The biological communities of urban ponds were markedly different to those of nonurban ponds, and the variability in urban pond community composition was greater than that in nonurban ponds, contrary to previous work showing homogenization of communities in urban areas. Positive spatial autocorrelation was recorded for urban and nonurban ponds at 0-50 km (distance between pond study sites) and negative spatial autocorrelation was observed at 100-150 km and was stronger in urban ponds in both cases. Ponds do not follow the same ecological patterns as terrestrial and lotic habitats (reduced taxonomic richness) in urban environments; in contrast, they support high taxonomic richness and contribute significantly to regional faunal diversity. Individual cities are complex structural mosaics which evolve over long periods of time and are managed in diverse ways. This facilitates the development of a wide range of environmental conditions and habitat niches in urban ponds which can promote greater heterogeneity between pond communities at larger scales. Ponds provide an opportunity for managers and environmental regulators to conserve and enhance freshwater biodiversity in urbanized landscapes whilst also facilitating

  6. Insect diversity and water quality parameters of two ponds of Chatla wetland, Barak valley, Assam

    Directory of Open Access Journals (Sweden)

    Susmita Gupta

    2012-12-01

    Full Text Available An investigation was carried out on two ponds of Chatla floodplain, Barak valley, Assam with special reference to aquatic insects. Pond 1 is purely a fish pond where as pond 2 is a community pond too. Present study revealed the status of water quality and in turn diversity, density, dominance and abundance of aquatic insects in both the ponds. Almost all the physico chemical parameters of both the ponds were found within permissible range for aquatic life .However in pond 2 level of phosphate was found little higher than pond 1 due to release of soaps and detergents by human influence. In both the ponds order Hemiptera showed maximum relative abundance ( 98% in pond 1 and 94% in pond 2. The study revealed lower diversity of aquatic insects in pond 2 than that in pond 1.

  7. Effect of stocking density on extensive production of freshwater shrimp in coal mine reclamation ponds

    Energy Technology Data Exchange (ETDEWEB)

    Tidwell, J.H.; Wynne, F.; Coyle, S.D. [Kentucky State Univ., Frankfort, KY (United States). Aquaculture Research Center; Grey, B. [Peabody Coal Co., Rockport, KY (United States); McGuire, J.

    1998-12-31

    The use of post-mining reclamation ponds for the production of freshwater shrimp was evaluated by examining different stocking densities. Juvenile shrimp (Macrobrachium rosenbergii) averaging 0.5g each were stocked into four existing ponds at Peabody`s Ken Surface Mine at 6,175; 12,350; 18,500; and 24,700/ha (2,500, 5,000, 7,500, and 10,000/acre) on June 1, 1995. Shrimp were fed twice a week for 103 days, with harvest conducted September 13, 1995. Survival averaged 40%, overall. Average individual weight size was inversely related to stocking density ranging from 52 g (8.7 shrimp/lb) at 6,175/ha to 20.3 g (22.7 shrimp/lb) at 18,500/acre. Total production was directly related to stocking density ranging from 97 kg/ha (86 lbs/acre) at low density to 211 kg/ha (188 lbs/acre) at 18,500/ha shrimp acre. The major difficulty was at harvest due to difficulty in draining ponds. Construction of designed culture ponds with gravity drains during reclamation could greatly enhance survival, harvestability, and commercial feasibility.

  8. TIGER SHRIMP (Penaeus monodon GROWTH AT DIFFERENT STOCKING DENSITIES IN HIGH SALINITY POND USING MANGROVE RESERVOIR

    Directory of Open Access Journals (Sweden)

    Gunarto Gunarto

    2006-06-01

    Full Text Available High salinity pond water ranging from 33—45 ppt between July and October is one of the problems occurred in western part of South Sulawesi brackishwater ponds. It is necessary to know if tiger shrimps grow well in such salinity, since the optimum salinity range for the growth of tiger shrimp is 15—25 ppt. The objective of the research is to know the tiger shrimp production at different stocking densities cultured in high salinity pond in mangrove reservoir. Twelve pond compartments of 500 m2 each were arranged randomly for three treatments of shrimp stocking densities i.e. 4 ,  6, and 8 pcs./m2 , where each treatment was in three replications. The result of study showed that shrimp production at 6 pieces/m2 was higher than that of 4 and 8 pieces/m2, with more efficient  feed conversion was obtained in this stocking density (1.3 compared to treatment 4 pieces/m2 (1.5 and treatment 8 pieces/m2 (>3.

  9. Pond and landscape determinants of Rana dalmatina population sizes in a Romanian rural landscape

    Science.gov (United States)

    Hartel, Tibor; Nemes, Szilárd; Cogălniceanu, Dan; Öllerer, Kinga; Moga, Cosmin Ioan; Lesbarrères, David; Demeter, László

    2009-01-01

    Amphibians are good indicators of human impact, declining steadily worldwide. We explored the relationships between the ponds and nearby landscape parameters and population size of the Agile Frog ( Rana dalmatina), estimated from the number of egg masses, in a cultural landscape within the central section of Târnava Mare Basin, Romania. Forty-three permanent ponds were surveyed in a 2600 km 2 area. The average number of egg masses per pond was 211.13 (SD = 426.41). The egg mass number was significantly and positively related to the emergent aquatic macrophyte cover (its effect peaks at around 50%) and the green connecting corridors between the ponds and forests, and negatively related to the extent of nearby urban areas. The proximity of the forest (positive effect) and the presence of high traffic roads (negative effect) were highly correlated with green corridors and further eliminated from the model due to multicollinearity. Both these variables had significant effects when incorporated in univariate models and multivariate models without green corridors. Since a large part of our study area was currently declared as Natura 2000 site, there is an increased need for management proposals and conservation applications for biodiversity, including amphibians. Rana dalmatina is an important species for monitoring because it is common in the studied area and is suited for short surveys.

  10. SCANNING ELECTRON MICROSCOPIC STUDY OF FETAL CHICKEN CALVARIAL OSTEOBLAST-LIKE CELLS CULTURED IN VITRO

    Institute of Scientific and Technical Information of China (English)

    柴本甫; 汤雪明; 徐荣辉; 朱雅萍

    1993-01-01

    Three types of osteoblast-like cells with different cnfigurations could be ob-tained through culturing fetal chicken calvaria in vitro. They were spindle-shaped cells,globular cells, and polygonal or squamous cells. With passage of culture time, there werechanges in configuration so that the spindle-shaped cells and the globular cells turnedgradually into squamous cells, in quantity which increased greatly to produce confluenceand multi-layer formation of cells, and in function as evidenced by emergence ofintracytoplasmic granules, reflecting collagen synthesis.

  11. On the role of the polychaete Dendronereis spp. i the transmission of white spot syndrome virus in shrimp ponds

    NARCIS (Netherlands)

    Desrina, Haryadi

    2014-01-01

    White spot syndrome virus (WSSV) is by far the most devastating shrimp virus. Control measures have lowered the WSSV incidence to various degrees, but the pathogen remains plaguing shrimp culture worldwide. Continuous exposure may cause WSSV to adapt and infect non-crustacean benthic fauna in ponds

  12. Performance evaluation of four different methods for circulating water in commercial-scale, split-pond aquaculture systems

    Science.gov (United States)

    The split-pond consists of a fish-culture basin that is connected to a waste-treatment lagoon by two conveyance structures. Water is circulated between the two basins with high-volume pumps and many different pumping systems are being used on commercial farms. Pump performance was evaluated with fou...

  13. Fouling organisms composition and secondary productivity of discharged water ponds of Atlantic salmon (Salmo salar) indoor intensive culture system%大西洋鲑工厂化养殖排放水池塘的污损生物组成及次级生产力评估

    Institute of Scientific and Technical Information of China (English)

    李应东; 刘媛; 崔朝霞

    2015-01-01

    为了对水产养殖废水进行综合利用,以减少对环境污染,增加养殖效益,2014年7—10月对大西洋鲑( Salmo salar)工厂化养殖车间排放水池塘中底栖生物的组成和次级生产力进行了调查和评估。结果显示,排放水池塘中沉积物量和底栖生物量与养殖废水的排放时间成正比;沉积物中,共检出底栖无脊椎动物4种,分别为线虫( Turbatrxi sp.)、才女虫( Polydora sp.)、小头虫( Capitella sp.)和钩虾( Corophium sp.),均为污损指示生物。其中,才女虫和钩虾的生物量和丰度与沉积物量呈显著正相关(P<0.05),小头虫、才女虫和钩虾的次级生产力分别为11.1、1149.1和702.2 g/m2 a,显著高于正常海域( P<0.05)。研究表明,该养殖废水中底栖污损生物的次级生产力高,具有较高的再利用价值。%To provide guidance for utilizing aquaculture wastewater, reducing environmental pollution and increasing farming profits, we investigated the benthonic organisms composition and secondary productivity in discharged water ponds of Salmo salar indoor intensive culture workshop, from July to October in 2014. Results showed that the sediments volume and biomasses of benthic organisms in discharge water ponds were directly proportional to the drainage time.Four species of zoobenthos were identified, including Turbatrix sp., Polydora sp., Capitella sp.and Corophium sp., which are all bioindicators, and there was a significant positive correlation between the amount of sediments and the biomasses of Capitella sp.and Corophium sp.as well as their richness (P<0.05).Secondary productivity of Capitella sp., Polydora sp.and Corophium sp. were 11.1, 1149.1 and 702.2 g/m2 a, respectively, which was significantly higher than those of outdoor seas (P<0.05).In conclusion, the fouling organisms of discharged water have high valuable potential as baits for other aquatic animals.

  14. 陶粒浮床对草鱼养殖池塘水质和浮游植物的影响%THE EFFECTS OF A NEW CERAMSITE ECOLOGICAL FLOATING BED ON THE WATER QUALITY AND PHYTOPLANKTON IN GRASS CRAP CULTURE PONDS

    Institute of Scientific and Technical Information of China (English)

    李晓莉; 陶玲; 张世羊; 赵晓杰; 陆光全; 李谷

    2015-01-01

    and regular surveys on the phytoplankton community and the water quality indexes in six grass crap culture ponds from May to October in 2013. Ceramsite ecological floating beds were applied in three ponds as the test groups and the other three were the control groups. During the culture period, we identified 179 species that belonged to 8 phyla and 111 genera. Ninety-three species were Chlorophyta, 25 were Cyanophyta, 23 were Bacil-lariophyta, 17 were Euglenophyta, 6 were Xanthophyta, 5 were Dinophyta, 5 were Cryptophyta and 5 were Chrysophyta. In the presence of the new ceramsite ecological floating bed, the test groups exhibited higher water transparency and lower concentrations of major nutritive salts compared to the control, and there was little fluctuation in the physi-cal-chemical indexes during the culture. There was a remarkable difference in the planktonic algae community between the test and the control groups in the middle and later culture period. In the mean while, the number of species in the test groups was higher than that in the control groups. There was a insignificant difference in the quantity of phytoplankton between the test and the control groups of which the ranges were 101.95×106—614.95×106 ind./L and 151.43×106—612.60×106 ind./L respectively. The ranges of biomass were 90.79—402.85 mg/L and 116.33—831.55 mg/L respectively, which were significantly different between the two groups in the middle and later culture period. The contribution of Chlorophyta and Cyanophyta was over 90%. The structure of phytoplankton community showed an ob-vious seasonal variation: the density and biomass of Chlorophyta first increased and then decreased, while those of Cyanophyta had an opposite trend. In the beginning, Scenedesmus was the dominant species in all ponds; a month later, Merismopedia and Microcystis were dominant in the control and Scenedesmus in the test groups; Merismopedia was the dominant species in July and August and then Scenedesmus

  15. Characterization of Amoeboaphelidium protococcarum, an algal parasite new to the cryptomycota isolated from an outdoor algal pond used for the production of biofuel.

    Science.gov (United States)

    Letcher, Peter M; Lopez, Salvador; Schmieder, Robert; Lee, Philip A; Behnke, Craig; Powell, Martha J; McBride, Robert C

    2013-01-01

    Mass culture of algae for the production of biofuels is a developing technology designed to offset the depletion of fossil fuel reserves. However, large scale culture of algae in open ponds can be challenging because of incidences of infestation with algal parasites. Without knowledge of the identity of the specific parasite and how to control these pests, algal-based biofuel production will be limited. We have characterized a eukaryotic parasite of Scenedesmus dimorphus growing in outdoor ponds used for biofuel production. We demonstrated that as the genomic DNA of parasite FD01 increases, the concentration of S. dimorphus cells decreases; consequently, this is a highly destructive pathogen. Techniques for culture of the parasite and host were developed, and the endoparasite was identified as the Aphelidea, Amoeboaphelidium protococcarum. Phylogenetic analysis of ribosomal sequences revealed that parasite FD01 placed within the recently described Cryptomycota, a poorly known phylum based on two species of Rozella and environmental samples. Transmission electron microscopy demonstrated that aplanospores of the parasite produced filose pseudopodia, which contained fine fibers the diameter of actin microfilaments. Multiple lipid globules clustered and were associated with microbodies, mitochondria and a membrane cisternae, an arrangement characteristic of the microbody-lipid globule complex of chytrid zoospores. After encystment and attachment to the host cells, the parasite injected its protoplast into the host between the host cell wall and plasma membrane. At maturity the unwalled parasite occupied the entire host cell. After cleavage of the protoplast into aplanospores, a vacuole and lipids remained in the host cell. Amoeboaphelidium protococcarum isolate FD01 is characteristic of the original description of this species and is different from strain X-5 recently characterized. Our results help put a face on the Cryptomycota, revealing that the phylum is more

  16. Characterization of Amoeboaphelidium protococcarum, an algal parasite new to the cryptomycota isolated from an outdoor algal pond used for the production of biofuel.

    Directory of Open Access Journals (Sweden)

    Peter M Letcher

    Full Text Available Mass culture of algae for the production of biofuels is a developing technology designed to offset the depletion of fossil fuel reserves. However, large scale culture of algae in open ponds can be challenging because of incidences of infestation with algal parasites. Without knowledge of the identity of the specific parasite and how to control these pests, algal-based biofuel production will be limited. We have characterized a eukaryotic parasite of Scenedesmus dimorphus growing in outdoor ponds used for biofuel production. We demonstrated that as the genomic DNA of parasite FD01 increases, the concentration of S. dimorphus cells decreases; consequently, this is a highly destructive pathogen. Techniques for culture of the parasite and host were developed, and the endoparasite was identified as the Aphelidea, Amoeboaphelidium protococcarum. Phylogenetic analysis of ribosomal sequences revealed that parasite FD01 placed within the recently described Cryptomycota, a poorly known phylum based on two species of Rozella and environmental samples. Transmission electron microscopy demonstrated that aplanospores of the parasite produced filose pseudopodia, which contained fine fibers the diameter of actin microfilaments. Multiple lipid globules clustered and were associated with microbodies, mitochondria and a membrane cisternae, an arrangement characteristic of the microbody-lipid globule complex of chytrid zoospores. After encystment and attachment to the host cells, the parasite injected its protoplast into the host between the host cell wall and plasma membrane. At maturity the unwalled parasite occupied the entire host cell. After cleavage of the protoplast into aplanospores, a vacuole and lipids remained in the host cell. Amoeboaphelidium protococcarum isolate FD01 is characteristic of the original description of this species and is different from strain X-5 recently characterized. Our results help put a face on the Cryptomycota, revealing that the

  17. Thermal Efficiency for Each Zone of a Solar Pond

    Institute of Scientific and Technical Information of China (English)

    BEZ(I)R C(I)CEK Nalan; SAH(I)N SENCAN Arzu

    2011-01-01

    A salt gradient solar pond with a surface area of 3.5×3.5 m2 and a depth of 2m is built.Two collapsible covers are used to reduce thermal energy loss from the surface of the solar pond during the night and to increase the thermal efficiency of the pond solar energy harvesting during daytime.The covers can be rotated between 0 and 180° by a controlled electric motor and has insulation and reflection properties.The thermal efficiency for each solar pond zone is investigated theoretically and experimentally.A salt gradient solar pond (SGSP) can store a portion of solar radiation as thermal energy for longterm use.Long-term energy storage in a solar pond is important for many applications,i.e.greenhouse heating or heating in buildings.%A salt gradient solar pond with a surface area of 3.5×3.5 m2 and a depth of 2m is built. Two collapsible covers are used to reduce thermal energy loss from the surface of the solar pond during the night and to increase the thermal efficiency of the pond solar energy harvesting during daytime. The covers can be rotated between 0 and 180° by a controlled electric motor and has insulation and reflection properties. The thermal efficiency for each solar pond zone is investigated theoretically and experimentally.

  18. Dairy farm wastewater treatment by an advanced pond system.

    Science.gov (United States)

    Craggs, R J; Tanner, C C; Sukias, J P S; Davies-Colley, R J

    2003-01-01

    Waste stabilisation ponds (WSPs) have been used for the treatment of dairy farm wastewater in New Zealand since the 1970s. The conventional two pond WSP systems provide efficient removal of wastewater BOD5 and total suspended solids, but effluent concentrations of other pollutants including nutrients and faecal bacteria are now considered unsuitable for discharge to waterways. Advanced Pond Systems (APS) provide a potential solution. A pilot dairy farm APS consisting of an Anaerobic pond (the first pond of the conventional WSP system) followed by three ponds: a High Rate Pond (HRP), an Algae Settling Pond (ASP) and a Maturation Pond (which all replace the conventional WSP system facultative pond) was evaluated over a two year period. Performance was compared to that of the existing conventional dairy farm WSP system. APS system effluent quality was considerably higher than that of the conventional WSP system with respective median effluent concentrations of BOD5: 34 and 108 g m(-3), TSS: 64 and 220 g m(-3), NH4-N: 8 and 29 g m(-3), DRP: 13 and 17 g m(-3), and E. coli: 146 and 16195 MPN/100 ml. APS systems show great promise for upgrading conventional dairy farm WSPs in New Zealand.

  19. Changes in tundra pond limnology: re-sampling Alaskan ponds after 40 years.

    Science.gov (United States)

    Lougheed, Vanessa L; Butler, Malcolm G; McEwen, Daniel C; Hobbie, John E

    2011-09-01

    The arctic tundra ponds at the International Biological Program (IBP) site in Barrow, AK, were studied extensively in the 1970s; however, very little aquatic research has been conducted there for over three decades. Due to the rapid climate changes already occurring in northern Alaska, identifying any changes in the ponds' structure and function over the past 30-40 years can help identify any potential climate-related impacts. Current research on the IBP ponds has revealed significant changes in the physical, chemical, and biological characteristics of these ponds over time. These changes include increased water temperatures, increased water column nutrient concentrations, the presence of at least one new chironomid species, and increased macrophyte cover. However, we have also observed significant annual variation in many measured variables and caution that this variation must be taken into account when attempting to make statements about longer-term change. The Barrow IBP tundra ponds represent one of the very few locations in the Arctic where long-term data are available on freshwater ecosystem structure and function. Continued monitoring and protection of these invaluable sites is required to help understand the implications of climate change on freshwater ecosystems in the Arctic.

  20. Holocene closure of Lib Pond, Marshall Islands.

    Science.gov (United States)

    Myhrvold, Conor L; Janny, Fran; Nelson, Daniel; Ladd, S Nemiah; Atwood, Alyssa; Sachs, Julian P

    2014-01-01

    Well-preserved sediment from closed water bodies of atolls such as Lib Pond are rare opportunities to reconstruct the past regional climate, which pieced together across a latitude and longitude range identify the range of movement patterns of wider scale climate phenomena such as the Intertropical Convergence Zone (ITCZ) and El Niño Southern Oscillation (ENSO). We conducted the first physico-chemical survey of Lib Pond, a shallow, closed-water saline lake located on remote and difficult to access Lib Island in the Marshall Islands at 8° 18' 48.99″ N, 167 22' 51.90″ E in the Pacific Ocean, in July 2009. We performed a bathymetric survey, recorded salinity, dissolved oxygen, pH, and temperature profiles, monitored the tidal variability, and conducted a vegetation survey surrounding the lake. From bathymetric data we calculated the lake volume, which we used to estimate the lake's salt budget, and ultimately the residence time of water in the lake basin. We took a series of sediment cores from the lake, cores which indicate Lib Island's changing environment and climate. Radiocarbon measurements determined sediment age, and reveal significant mixing over the last 2 ka of deposition. We conclude that prior to 3 ka, Lib Island was an atoll with a central lagoon connected to the open ocean, which was then closed off from the open ocean to form the brackish system that exists today. We predict that the sediment accumulation in Lib Pond evident today will continue. As seawater is inhibited from exchanging with fresh water, Lib Pond will become a shallower lake with increasingly fresh water.

  1. Cibola High Levee Pond annual report 2004

    Science.gov (United States)

    Mueller, Gordon A.; Carpenter, Jeanette; Marsh, Paul C.

    2005-01-01

    This represents the fourth and last annual report of a five year study investigating the early life ecology of the bonytail and razorback sucker at Cibola High Levee Pond. The work in 2004 included: telemetry studies, collection of physical water quality measurements, zooplankton samples, netting fish, the collection of scale samples for aging, predator/prey tank tests and a preliminary analysis of the data base.

  2. Holocene closure of Lib Pond, Marshall Islands.

    Directory of Open Access Journals (Sweden)

    Conor L Myhrvold

    Full Text Available Well-preserved sediment from closed water bodies of atolls such as Lib Pond are rare opportunities to reconstruct the past regional climate, which pieced together across a latitude and longitude range identify the range of movement patterns of wider scale climate phenomena such as the Intertropical Convergence Zone (ITCZ and El Niño Southern Oscillation (ENSO. We conducted the first physico-chemical survey of Lib Pond, a shallow, closed-water saline lake located on remote and difficult to access Lib Island in the Marshall Islands at 8° 18' 48.99″ N, 167 22' 51.90″ E in the Pacific Ocean, in July 2009. We performed a bathymetric survey, recorded salinity, dissolved oxygen, pH, and temperature profiles, monitored the tidal variability, and conducted a vegetation survey surrounding the lake. From bathymetric data we calculated the lake volume, which we used to estimate the lake's salt budget, and ultimately the residence time of water in the lake basin. We took a series of sediment cores from the lake, cores which indicate Lib Island's changing environment and climate. Radiocarbon measurements determined sediment age, and reveal significant mixing over the last 2 ka of deposition. We conclude that prior to 3 ka, Lib Island was an atoll with a central lagoon connected to the open ocean, which was then closed off from the open ocean to form the brackish system that exists today. We predict that the sediment accumulation in Lib Pond evident today will continue. As seawater is inhibited from exchanging with fresh water, Lib Pond will become a shallower lake with increasingly fresh water.

  3. Rapid surface-water volume estimations in beaver ponds

    Science.gov (United States)

    Karran, Daniel J.; Westbrook, Cherie J.; Wheaton, Joseph M.; Johnston, Carol A.; Bedard-Haughn, Angela

    2017-02-01

    Beaver ponds are surface-water features that are transient through space and time. Such qualities complicate the inclusion of beaver ponds in local and regional water balances, and in hydrological models, as reliable estimates of surface-water storage are difficult to acquire without time- and labour-intensive topographic surveys. A simpler approach to overcome this challenge is needed, given the abundance of the beaver ponds in North America, Eurasia, and southern South America. We investigated whether simple morphometric characteristics derived from readily available aerial imagery or quickly measured field attributes of beaver ponds can be used to approximate surface-water storage among the range of environmental settings in which beaver ponds are found. Studied were a total of 40 beaver ponds from four different sites in North and South America. The simplified volume-area-depth (V-A-h) approach, originally developed for prairie potholes, was tested. With only two measurements of pond depth and corresponding surface area, this method estimated surface-water storage in beaver ponds within 5 % on average. Beaver pond morphometry was characterized by a median basin coefficient of 0.91, and dam length and pond surface area were strongly correlated with beaver pond storage capacity, regardless of geographic setting. These attributes provide a means for coarsely estimating surface-water storage capacity in beaver ponds. Overall, this research demonstrates that reliable estimates of surface-water storage in beaver ponds only requires simple measurements derived from aerial imagery and/or brief visits to the field. Future research efforts should be directed at incorporating these simple methods into both broader beaver-related tools and catchment-scale hydrological models.

  4. Advanced reclamation of coal refuse ponds

    Energy Technology Data Exchange (ETDEWEB)

    Honaker, R.Q.; Chugh, Y.P.; Patwardhan, A. [Southern Illinois Univ., Carbondale, IL (United States). Dept. of Mining and Mineral Resources Engineering

    1998-12-31

    A vast number of coal refuse ponds represent a significant economical resource base that may also be considered to be environmentally harmful. The fine coal fraction in a preparation plant consists of the purest particles in the entire preparation plant and, thus, if recovered, could enhance the quality of the plant product. However, until recently, the ability to effectively recover fine coal has been limited due to the lack of efficient fine particle separation technologies. As a result, a large portion of the fine coal produced in the US during this century has been disposed into refuse pond along with the acid producing components of the associated gangue material. Research conducted by Southern Illinois University scientists has found that advanced fine coal cleaning technologies can be used to recover high quality coal from refuse ponds while also utilizing a novel technique for neutralizing the acid generation potential of the pyrite-rich reject stream. Various circuitry arrangements will be discussed and metallurgical results presented in this publication.

  5. Nitrogen dynamics model in zero water exchange, low salinity intensive ponds of white shrimp, Litopenaeus vannamei, at Colima, Mexico

    Directory of Open Access Journals (Sweden)

    Francisco A Castillo-Soriano

    2013-03-01

    Full Text Available We present a mathematical model based on differential equations describing the dynamics of nitrogen (NH4+, NO2-, NO3- and organic nitrogen in phytoplankton in ponds of white shrimp (Litopenaeus vannamei, with low salinity and zero turnovers, from planting to harvest. The model predicts the results of commercial production in three ponds. We show that this culture system, without replacement, retains the nitrogen and shrimp produced a lower feed conversion in comparison with systems with replacement. The model can be used to define strategies for improved performance.

  6. Alcohol production through volatile fatty acids reduction with hydrogen as electron donor by mixed cultures

    NARCIS (Netherlands)

    Steinbusch, K.J.J.; Hamelers, H.V.M.; Buisman, C.J.N.

    2008-01-01

    In this research we demonstrated a new method to produce alcohols. It was experimentally feasible to produce ethanol, propanol and butanol from solely volatile fatty acids (VFAs) with hydrogen as electron donor. In batch tests, VFAs such as acetic, propionic and butyric acids were reduced by mixed m

  7. Purification Performance and Production of a Re-circulating Pond Aquaculture System Based on Paddy Field

    Directory of Open Access Journals (Sweden)

    Gu Li

    2012-10-01

    Full Text Available Developing improved aquaculture systems with a more efficient use of water and less environmental impact is becoming a crying need. A re-circulating aquaculture system consisting of paddy field and fish pond is a new culture mode due to aquaculture combing with agriculture. The present study focused on the purification capacity of the paddy field on nitrogen, phosphorus and organic matter, the fluctuation trend of water quality conditions during the whole rearing process and the culture efficacy of the main culture species of grass carp (Ctenopharyngodon idella. The results were as follows: under a flow rate of 1.4-5.5 m3/h for the recirculation treatment, the average removal rate of ammonia nitrogen, nitrate nitrogen, total nitrogen, total phosphorus and biochemical oxygen demand for the aquaculture effluent amounted to 40.5, 43.5, 31.9, 23.9, 20.7 and 52.4%, respectively, But the dissolved oxygen content in the rice fields increased obviously. During the whole process of fish rearing, the main physicochemical parameters of water quality for the experimental ponds were all maintained at a suitable level for the growth of the grass carp. In addition, there were significant differences (p<0.05 in DO, TSS, NH4+ -N, NO--N, BOD5 and Chl-&alpha between the experimental and control ponds. As far as the yield per unit and survival rate was concerned, the level of the experimental ponds was obviously higher than that of the control, while the feed conversion ratio displayed the opposite trend. Overall, the new aquaculture system realized the double aims of water reuse and the reduction of waste water discharge.

  8. A pre-enrichment step is essential for detection of Campylobacter sp. in turbid pond water.

    Science.gov (United States)

    Abulreesh, H H; Paget, T A; Goulder, R

    2014-06-01

    This work aimed to detect Campylobacter species from naturally contaminated turbid pond water by PCR. A total of 16 water samples were collected from a turbid village pond. Four methods of DNA extraction were applied to centrifuge pellets from eight 100 ml pond water samples prior to attempted detection of Campylobacter by PCR without an enrichment step. These methods were (1) Tris-HCl and sodium dodecyl sulfate followed by phenol:chloroform:isoamylalcohol extraction followed by treatment with DNA clean up kit, (2) proteinase K, (3) Chelex® 100, and (4) boiling. The other eight pond water samples (10 ml and 100 ml) were filtered and filters were incubated overnight in Preston enrichment broth. The centrifuge pellets obtained from enrichment cultures were treated by proteinase K for DNA extraction. Primers CF03 and CF04 for the flagellin genes (flaA and flaB) of Campylobacter jejuni and Campylobacter coli were used for amplifying the extracted DNA. The DNA extracted from eight-100 ml pond water samples that were not subject to selective enrichment was never amplified with primers CF03 and CF04, hence Campylobacter was not detected. In contrast, the DNA that was from samples that were subjected to a selective enrichment step in Preston broth prior to PCR assay always gave amplified bands of 340-380 bp, therefore the presence of Campylobacter was confirmed. Detection of campylobacters from naturally contaminated, turbid, environmental water may not be feasible by direct PCR assay because of low numbers and the presence of high concentration of humic matter and other PCR inhibitors. The enrichment of water samples in selective broth, however, facilitated PCR detection of Campylobacter probably by increasing cell number and by diluting PCR inhibitors.

  9. A survey of catfish pond water chemistry parameters for copper toxicity modelling

    Science.gov (United States)

    Water samples were collected from 20 catfish ponds in 2015 to obtain data useful in predicting copper toxicity and chemical behavior. Ponds were located in major catfish producing areas of west Alabama, east Arkansas, and Mississippi. Pond types included traditional levee ponds, split-ponds, water...

  10. Relationship Between Accumulation and Influx of Pollutants in Highway Ponds

    DEFF Research Database (Denmark)

    Bentzen, Thomas Ruby; Larsen, Torben; Rasmussen, Michael R.

    The paper discusses the long term mass balance of pollutants in highway ponds. The accumulations of five polycyclic aromatic hydrocarbons (PAHs) and six heavy metals have been measured in eight Danish detention ponds, which receive runoff from highways only. For each pollutant the accumulation has...... been compared to the long-term influx, estimated from short-term measurements of concentrations in highway runoff. The results show that a large proportion of the incoming heavy metals in short-term runoff events has accumulated in the ponds. This is not the case for the toxic organic compounds....... The results also show that the accumulation rates for the heavy metals depend significantly on the relative pond area (pond area divided by catchment area). The conclusion is that the mass balances of heavy metals and PAHs in highway ponds can be estimated with acceptable accuracy from a combination of short...

  11. 细基江蓠(Gracilaria tenuistipitata)对海水池塘养殖区Cu2+生物修复的初步研究%BIOREMEDIATION OF Cu2+ POLLUTED ANIMAL CULTURE PONDS BY SEAWEED GRACILARIA TENUISTIPITATA

    Institute of Scientific and Technical Information of China (English)

    丁兰平; 徐佩杭; 杨宇峰; 黄冰心

    2014-01-01

    随着海水养殖业迅速发展,食用海产品重金属(如Cu、Cd等)超标问题日益突出.作为提取藻胶原材料及海洋养殖动物饲料的细基江蓠,可以大规模生长在海水池塘养殖区,有望用于该水域重金属污染的生物修复.本实验通过研究细基江蓠(Gracilaria tenuistipitata)在5个不同Cu2+浓度梯度(0、0.05、0.2、0.8、2.0mg/L)环境下的自身生长状况,及其对Cu2+的吸收富集情况,初步探究了细基江蓠对海水池塘养殖区Cu2+的生物修复能力.实验结果显示细基江蓠对Cu2+有较强的耐受性和吸收富集能力,在0.8mg/L Cu2+浓度下细基江蓠既能保证正常生长,又能吸附水体中最大量的Cu2+.%Heavy metals (such as Cu and Cd) in seafood have become increasingly an alarming issue as the result of rapid development of mariculture.Gracilaria tenuistipitata is used as a material for extracting phycocolloid and fodder for seawater aquaculture.On the other hand,as it proliferates quickly in a large scale,it can be applied in aquaculture for bioremediation against heavy metal pollution in culture ponds.In this study,G.tenuistipitata was studied for understanding its absorption to and capability against Cu2+ pollution in 5 different Cu2+ concentrations (0,0.05,0.2,0.8,2.0mg/L).It was found that G.tenuistipitata could tolerate and absorb strongly Cu2+.Under 0.8mg/L concentration,it could grow normally with maximum Cu2+ adsorption.

  12. Transition in the fractal geometry of Arctic melt ponds

    OpenAIRE

    Hohenegger, C.; B. Alali; K. R. Steffen; D. K. Perovich; K. M. Golden

    2012-01-01

    During the Arctic melt season, the sea ice surface undergoes a remarkable transformation from vast expanses of snow covered ice to complex mosaics of ice and melt ponds. Sea ice albedo, a key parameter in climate modeling, is determined by the complex evolution of melt pond configurations. In fact, ice–albedo feedback has played a major role in the recent declines of the summer Arctic sea ice pack. However, understanding melt pond evolution remains a significant challenge to improving climate...

  13. Impact of fish pond harvest on water quality especially on

    OpenAIRE

    FREIDINGER, Jan

    2016-01-01

    The topic of this thesis is the impact of fish pond harvest on water quality especially on concentration of suspended solids and phosphorous. Goal of the study is to contribute to ongoing discussion about carp aquaculture's role in fresh water pollution. Sampling was carried out in five carp ponds in the Třeboňsko Protected Landscape Area. Main monitored parameters were concentration of suspended solids and total phosphorous during pond drainage and fish harvest.Results of the study confirmed...

  14. 不同规格和投苗密度对仿刺参池塘网箱保苗效果的影响%Effects of Different Size and Density on Intermediate Seedling Culture of Sea Cucumber,Apostichopus j aponicus in Net Cages Disposed in Earthen Ponds

    Institute of Scientific and Technical Information of China (English)

    吴艳庆; 张玉祥; 杜荣斌; 王志宝; 王仁龙; 刘立明; 李晓杰

    2016-01-01

    Seedling culture of sea cucumber (A postichopus j aponicus) ,using net cages in earthen ponds , is a semi‐ecological seedling protection pattern arising in recent years .Field experiment was conducted in net cages set in earthen pond to investigate the effects of size [large size (0 .093 ± 0 .004) g/ind and small size (0 .024 ± 0 .001) g/ind] and density (low density 125 g/m3 ,middle density 250 g/m3 and high density 375 g/m3 ) on grow th ,yield and survival rate of sea cucumber during intermediate seedling culture period from July to October in 2014 .The results showed that the body weight and the specific growth rate of seedling were in low density higher than that in middle density and high density in the same size ,that the large size had significantly higher survival rate than the small size in the same density groups (P0 .05) ,higher net production of seedling in low density than that in middle density and high density .The two‐way ANOVA revealed that the main effect of size and the interaction of two factors had significant influence on the survival rate (P0 .05) .The main effect of size and the interaction of the two factors did not show significant influence on net production (P>0 .05) ,while main effect of density had a significant influence on net production (P<0 .05) .Therefore ,releasing of large size seedling with low density could not only ensure high survival rate and net production ,but also save seedling resources and feed quantity ,reduce the production and management cost per unit area ,eleva‐ting input‐output ratio and economic benefit during intermediate seedling culture period of sea cucumber .%仿刺参室外池塘网箱保苗是近年来兴起的一种半生态式的保苗方式。于2014年7—11月在仿刺参室外池塘网箱保苗期间,通过现场试验比较研究了不同投苗规格[大规格(0.093±0.004) g/头,小规格(0.024±0.001) g/头]和密度(低密度125 g/m3、中密度250 g/m3

  15. Effect of heavy metals on soil mineral surfaces and bioretention pond performance

    Science.gov (United States)

    Zhang, H.; Olson, M. S.

    2009-12-01

    Haibo Zhang and Mira S. Olson Department of Civil, Architectural, and Environmental Engineering, Drexel University, 3141 Chestnut Street, Philadelphia, PA 19104 As urban stormwater runoff flows across impervious surfaces, it collects and accumulates pollutants that are detrimental to the quality of local receiving water bodies. Heavy metal pollution, such as copper, lead and zinc, has been a concern in urban stormwater runoff. In addition, the presence of bacteria in stormwater has been frequently reported. The co-existence of both heavy metals and bacteria in stormwater and their complex interactions determine their transport and removal through bioretention pond. Stormwater runoff was sampled from a bioretention pond in Philadelphia, PA. The concentration of copper, lead and zinc were measured as 0.086ppm, 0.083ppm and 0.365ppm, respectively. Batch experiments were conducted with solutions of pure copper, lead and zinc, and with a synthetic stormwater solution amended with copper, lead and zinc. The solution was buffered to pH 7, within the range of the observed stormwater pH. In pure heavy metal solutions, the sorption of copper, lead and zinc onto soil are 96%, 99% and 85%, respectively. In synthetic stormwater containing nutrients and all three metals, the sorption of lead is 97%, while copper and zinc decrease to 29% and 71%, respectively. Mineralogy of a soil sample taken from the bioretention pond was analyzed using a scanning electron microscope (SEM) and compared before and after sorption experiments. Sorption and complexation of heavy metals is likely to change the mineralogy of soil particle surfaces, which will affect the attachment of bacteria and therefore its transport through soil. This study will benefit long-term predictions of the performance of bioretention ponds for urban stormwater runoff treatment. Keyword: Heavy metal pollution, sorption, surface complexation, urban stormwater runoff, bioretention pond

  16. Evaluation of microbial biofilm communities from an Alberta oil sands tailings pond.

    Science.gov (United States)

    Golby, Susanne; Ceri, Howard; Gieg, Lisa M; Chatterjee, Indranil; Marques, Lyriam L R; Turner, Raymond J

    2012-01-01

    Bitumen extraction from the oil sands of Alberta has resulted in millions of cubic meters of waste stored on-site in tailings ponds. Unique microbial ecology is expected in these ponds, which may be key to their bioremediation potential. We considered that direct culturing of microbes from a tailings sample as biofilms could lead to the recovery of microbial communities that provide good representation of the ecology of the tailings. Culturing of mixed species biofilms in vitro using the Calgary Biofilm Device (CBD) under aerobic, microaerobic, and anaerobic growth conditions was successful both with and without the addition of various growth nutrients. Denaturant gradient gel electrophoresis and 16S rRNA gene pyrotag sequencing revealed that unique mixed biofilm communities were recovered under each incubation condition, with the dominant species belonging to Pseudomonas, Thauera, Hydrogenophaga, Rhodoferax, and Acidovorax. This work used an approach that allowed organisms to grow as a biofilm directly from a sample collected of their environment, and the biofilms cultivated in vitro were representative of the endogenous environmental community. For the first time, representative environmental mixed species biofilms have been isolated and grown under laboratory conditions from an oil sands tailings pond environment and a description of their composition is provided.

  17. Transition in the fractal geometry of Arctic melt ponds

    Directory of Open Access Journals (Sweden)

    C. Hohenegger

    2012-06-01

    Full Text Available During the Arctic melt season, the sea ice surface undergoes a remarkable transformation from vast expanses of snow covered ice to complex mosaics of ice and melt ponds. Sea ice albedo, a key parameter in climate modeling, is determined by the complex evolution of melt pond configurations. In fact, ice-albedo feedback has played a major role in the recent declines of the summer Arctic sea ice pack. However, understanding melt pond evolution remains a significant challenge to improving climate projections. By analyzing area-perimeter data from hundreds of thousands of melt ponds, we find here an unexpected separation of scales, where pond fractal dimension D transitions from 1 to 2 around a critical length scale of 100 m2 in area. Pond complexity increases rapidly through the transition as smaller ponds coalesce to form large connected regions, and reaches a maximum for ponds larger than 1000 m2 whose boundaries resemble space filling curves with D ≈ 2. These universal features of Arctic melt pond evolution are similar to phase transitions in statistical physics. The results impact sea ice albedo, the transmitted radiation fields under melting sea ice, the heat balance of sea ice and the upper ocean, and biological productivity such as under ice phytoplankton blooms.

  18. Simple intervention to reduce mosquito breeding in waste stabilisation ponds

    DEFF Research Database (Denmark)

    Ensink, Jeroen H J; Mukhtar, Muhammad; van der Hoek, Wim

    2007-01-01

    Waste stabilisation ponds (WSP) are the preferred method for treatment of urban wastewater in low-income countries but, especially in arid regions, the pond systems can be important breeding sites for mosquitoes of medical importance. In a WSP system in Faisalabad, Pakistan, we assessed the impact...... of simple environmental interventions on mosquito occurrence and abundance. Reducing the amount of floating matter in the ponds, eliminating emergent vegetation and repairing cracks in the cement structure reduced the number of mosquito-positive samples in the intervention ponds to almost zero, whereas...

  19. Bioaccumulation of heavy metals in two wet retention ponds

    DEFF Research Database (Denmark)

    Søberg, Laila C.; Vollertsen, Jes; Blecken, Godecke-Tobias;

    2016-01-01

    Metal accumulation in stormwater ponds may contaminate the inhabiting fauna, thus jeopardizing their ecosystem servicing function. We evaluated bioaccumulation of metals in natural fauna and caged mussel indicator organisms in two wet retention ponds. Mussel cages were distributed throughout...... the ponds to detect bioaccumulation gradients and obtain a time-integrated measure of metal bioavailability. We further investigated if sediment metal concentrations correlate with those in the fauna and mussels. Metal concentrations in the fauna tended to be higher in the ponds than in a reference lake...

  20. Transition in the fractal geometry of Arctic melt ponds

    Directory of Open Access Journals (Sweden)

    C. Hohenegger

    2012-10-01

    Full Text Available During the Arctic melt season, the sea ice surface undergoes a remarkable transformation from vast expanses of snow covered ice to complex mosaics of ice and melt ponds. Sea ice albedo, a key parameter in climate modeling, is determined by the complex evolution of melt pond configurations. In fact, ice–albedo feedback has played a major role in the recent declines of the summer Arctic sea ice pack. However, understanding melt pond evolution remains a significant challenge to improving climate projections. By analyzing area–perimeter data from hundreds of thousands of melt ponds, we find here an unexpected separation of scales, where pond fractal dimension D transitions from 1 to 2 around a critical length scale of 100 m2 in area. Pond complexity increases rapidly through the transition as smaller ponds coalesce to form large connected regions, and reaches a maximum for ponds larger than 1000 m2, whose boundaries resemble space-filling curves, with D ≈ 2. These universal features of Arctic melt pond evolution are similar to phase transitions in statistical physics. The results impact sea ice albedo, the transmitted radiation fields under melting sea ice, the heat balance of sea ice and the upper ocean, and biological productivity such as under ice phytoplankton blooms.

  1. Winter Growth of Carps under Different Semi-Intensive Culture Conditions

    Directory of Open Access Journals (Sweden)

    Nadia Nazish* and Abdul Mateen

    2011-04-01

    Full Text Available The experiment was planned to observe the influence of different semi intensive culture conditions i.e. organic and inorganic fertilizer with rice polish on the growth of carps during winter season. Two earthen ponds were selected and each pond was stocked with Silver carp (Hypophthalmichthys molitrix, Rohu (Labeo rohita and Mori (Cirrhinus mrigala at the ratio of 1:2:1 respectively with a total number of 44 fishes. Pond 1 was treated with poultry dropping and urea while pond 2 was treated with poultry dropping, urea and rice polish. The ponds were treated with at the rate of 0.2 g N/100g of wet body weight of fish. Fertilizers were added on weekly basis while rice polish was added daily. Total net fish production of pond 1 and pond 2 was remained 797.3 and 1033.0 kg/ha/year. The pond treated with fertilizer and artificial feed (rice polish showed 3.6% more fish production than the pond treated only with fertilizer. The physico-chemical parameters were measured on weekly basis. Temperature, light penetration, pH and planktonic biomass showed non-significant difference in both ponds. Pond 2 which was treated with poultry dropping, urea and rice polish showed 1.26 times greater fish growth than pond 1 which was treated with poultry dropping and urea.

  2. Feeding habits of Solea senegalensis in earthen ponds in Sado estuary

    Science.gov (United States)

    Castelo Branco, Maria Ana; Arruda, Marco A.; Gamito, Sofia

    2010-11-01

    The senegale sole, Solea senegalensis Kaup, 1858, is a commercially valuable fish and it is beginning to be cultured in a semi-intensive way in fish farms in southern European countries. The present study was initiated to investigate the diet of S. senegalensis under semi-extensive conditions. The feeding habits of sole were studied in two earthen ponds of a fish farm in the Sado estuary. In one earthen pond, artificial fish ration was given. S. senegalensis feeds on few prey items, its diet is mainly composed of insect larvae ( Chironomus salinarus) and polychaeta ( Hediste diversicolor). The diet composition of this species suggests feeding specialization, by consuming mainly annelids and insect larvae and by avoiding other items, extremely abundant in the environment, such as gastropods. In the water reservoir where ration was given, some fish consumed simultaneously benthic organism together with ration. However, benthic organisms seem to be the most important component of S. senegalensis diet.

  3. Salt-Pond Box Model (SPOOM) and Its Application to the Napa-Sonoma Salt Ponds, San Francisco Bay, California

    Science.gov (United States)

    Lionberger, Megan L.; Schoellhamer, David H.; Buchanan, Paul A.; Meyer, Scott

    2004-01-01

    A box model to simulate water volume and salinity of a salt pond has been developed by the U.S. Geological Survey to obtain water and salinity budgets. The model, SPOOM, uses the principle of conservation of mass to calculate daily pond volume and salinity and includes a salt crystallization and dissolution algorithm. Model inputs include precipitation, evaporation, infiltration, and water transfers. Salinity and water-surface-elevation data were collected monthly in the Napa-Sonoma Salt-Pond Complex from February 1999 through September 2001 and were used to calibrate and validate the model. The months when water transfers occurred were known but the magnitudes were unknown, so the magnitudes of water transfers were adjusted in the model to calibrate simulated pond volumes to measured pond volumes for three ponds. Modeled salinity was then compared with measured salinity, which remained a free parameter, in order to validate the model. Comparison showed good correlation between modeled and measured salinity. Deviations can be attributed to lack of water-transfer information. Water and salinity budgets obtained through modeling will be used to help interpret ecological data from the ponds. This model has been formulated to be applicable to the Napa-Sonoma salt ponds, but can be applied to other salt ponds.

  4. Application of polymeric flocculant for enhancing settling of the pond ash particles and water drainage from hydraulically stowed pond ash

    Institute of Scientific and Technical Information of China (English)

    Mishra Devi Prasad; Das Samir Kumar

    2013-01-01

    Delayed settling of the ash particles and poor drainage of water from the pond ash are the major problems faced during the hydraulic stowing of pond ash.In this study the effect of polymeric flocculant on settling of the ash particles and drainage of water during pond ash stowing are investigated.In addition,the parameters,viz.drainage and absorption of water during pond ash stowing are quantified by stowing a mine goaf model with pond ash slurries of five different concentrations added with and without flocculant.The study revealed that addition of only 5 × 10-6 of Sodium Carboxymethyl Cellulose (Na-CMC)flocculant with the pond ash slurries during stowing offers best result in terms of quicker settling of the ash particles and enhanced water drainage from the hydraulically stowed pond ash.Besides,it resulted in drainage of more than 85% of the total water used in the initial 45 min of stowing.The improvement in drainage is caused due to coagulation and flocculation of the pond ash particles because of charge neutralization and particle-particle bridging.This study may provide a basis for estimating the drainage and absorption of water during the real pond ash stowing operation in underground mines.

  5. International experience in tailings pond remediation

    Energy Technology Data Exchange (ETDEWEB)

    MacG. Robertson, A. [Robertson GeoConsultants Ltd., Vancouver (Canada)

    2001-07-01

    Tailings pond remediation is required primarily on mine closure. While mining is an ancient industry, requirement for mine facility remediation is a comparatively new development. Requirement for remediation has come about partly as a result of mans awareness of the environmental impacts of mining and his desire to minimize this, partly, as a result of the ever-increasing scale and production rates of tailings generation and the resulting increased environmental impacts and safety risks. The paper starts with a review of the evolution of mans intolerance of environmental impacts from tailings production and the assignment of liability to remediate such impacts. Many of the tailings ponds currently undergoing remediation were designed and constructed using methods and technology that would be considered inappropriate for new impoundments being designed and developed today. The paper reviews the history of tailings impoundment design and construction practice and the resulting inherent deficiencies that must be remediated. Current practices and future trends in tailings pond remediation are reviewed. The evolution of regulatory requirements is not only in terms of technical and safety criteria, but also in terms of financial and political risk. Perhaps the most substantive driver of risk management is today the requirement for corporate governance at mining company board level and oversight of new project development in the underdeveloped countries by the large financial institutions responsible for funding projects. Embarrassment in the public eye and punishment in the stock markets for poor environmental and safety performance is driving the need for efficient and effective risk management of potential impacts and the remediation to avoid these. A basis for practical risk management is described. (orig.)

  6. Phyllosphere mycobiota on garden ponds plants

    Directory of Open Access Journals (Sweden)

    Maria Kowalik

    2013-12-01

    Full Text Available Investigations were conducted on calamus, common cattail, soft rush, yellow iris and white water lily plants in twenty ponds in Malopolska and Podkarpacie Regions. Mycobiota existing in the phyllosphere caused discolouring and necroses of leaves and shoots. 88 species of mycobiota were identified and isolated from the diseased tissues. Dominant were Alternaria alternata, Epicoccum nigrum and Isaria farinosa. Fungi of genera: Aspergillus, Botrytis, Chaetomium, Cladosporium, Fusarium, Ilyonectria, Mortierella, Mucor, Penicillium, Phialophora, Phoma, Pleustomophora, Sordaria, Trichoderma and Umbelopsis were also numerous. The monophagous and the polyphagous were identified.

  7. First description of underwater acoustic diversity in three temperate ponds

    Directory of Open Access Journals (Sweden)

    Camille Desjonquères

    2015-11-01

    Full Text Available The past decade has produced an increased ecological interest in sonic environments, or soundscapes. However, despite this rise in interest and technological improvements that allow for long-term acoustic surveys in various environments, some habitats’ soundscapes remain to be explored. Ponds, and more generally freshwater habitats, are one of these acoustically unexplored environments. Here we undertook the first long term acoustic monitoring of three temperate ponds in France. By aural and visual inspection of a selection of recordings, we identified 48 different sound types, and according to the rarefaction curves we calculated, more sound types are likely present in one of the three ponds. The richness of sound types varied significantly across ponds. Surprisingly, there was no pond-to-pond daily consistency of sound type richness variation; each pond had its own daily patterns of activity. We also explored the possibility of using six acoustic diversity indices to conduct rapid biodiversity assessments in temperate ponds. We found that all indices were sensitive to the background noise as estimated through correlations with the signal-to-noise ratio (SNR. However, we determined that the AR index could be a good candidate to measure acoustic diversities using partial correlations with the SNR as a control variable. Yet, research is still required to automatically compute the SNR in order to apply this index on a large data set of recordings. The results showed that these three temperate ponds host a high level of acoustic diversity in which the soundscapes were variable not only between but also within the ponds. The sources producing this diversity of sounds and the drivers of difference in daily song type richness variation both require further investigation. Such research would yield insights into the biodiversity and ecology of temperate ponds.

  8. Experimental canopy removal enhances diversity of vernal pond amphibians.

    Science.gov (United States)

    Skelly, David K; Bolden, Susan R; Freidenburg, L Kealoha

    2014-03-01

    Vernal ponds are often treated as protected environments receiving special regulation and management. Within the landscapes where they are found, forest vegetation frequently dominates surrounding uplands and can grow to overtop and shade pond basins. Two bodies of research offer differing views of the role of forest canopy for vernal pond systems. Studies of landscape conversion suggest that removing forest overstory within uplands can cause local extinctions of amphibians by altering terrestrial habitat or hindering movement. Studies of canopy above pond basins imply an opposite relationship; encroachment of overstory vegetation can be associated with local extinctions potentially via changes in light, thermal, and food resource environments. Unresolved uncertainties about the role of forest canopy reveal significant gaps in our understanding of wetland species distributions and dynamics. Any misunderstanding of canopy influences is simultaneously important to managers because current practices emphasize promoting or conserving vegetation growth particularly within buffers immediately adjacent to ponds. We evaluated this apparent contradiction by conducting a landscape-scale, long-term experiment using 14 natural vernal ponds. Tree felling at six manipulated ponds was limited in spatial scope but was nevertheless effective in increasing water temperature. Compared with eight control ponds, manipulated ponds maintained more amphibian species during five years post-manipulation. There was little evidence that any species was negatively influenced, and the reproductive effort of species for which we estimated egg inputs maintained pretreatment population densities in manipulated compared with control ponds. Overall, our experiment shows that a carefully circumscribed reduction of overhead forest canopy can enhance the capacity of vernal ponds to support wildlife diversity and suggests a scale dependence of canopy influences on amphibians. These findings have

  9. The critical role of islands for waterbird breeding and foraging habitat in managed ponds of the South Bay Salt Pond Restoration Project, South San Francisco Bay, California

    Science.gov (United States)

    Ackerman, Joshua T.; Hartman, C. Alex; Herzog, Mark P.; Smith, Lacy M.; Moskal, Stacy M.; De La Cruz, Susan E. W.; Yee, Julie L.; Takekawa, John Y.

    2014-01-01

    The South Bay Salt Pond Restoration Project aims to restore 50–90 percent of former salt evaporation ponds into tidal marsh in South San Francisco Bay, California. However, large numbers of waterbirds use these ponds annually as nesting and foraging habitat. Islands within ponds are particularly important habitat for nesting, foraging, and roosting waterbirds. To maintain current waterbird populations, the South Bay Salt Pond Restoration Project plans to create new islands within former salt ponds in South San Francisco Bay. In a series of studies, we investigated pond and individual island attributes that are most beneficial to nesting, foraging, and roosting waterbirds.

  10. Evaluation of the viability of cultured corneal endothelial cells by quantitative electron probe X-ray microanalysis.

    Science.gov (United States)

    Alaminos, M; Sanchez-Quevedo, M C; Muñoz-Avila, J I; García, J M; Crespo, P V; González-Andrades, M; Campos, A

    2007-06-01

    Construction of artificial organs and tissues by tissue engineering is strongly dependent on the availability of viable cells. For that reason, the viability and the physiological status of cells kept in culture must be evaluated before the cells can be used for clinical purposes. In this work, we determined the viability of isolated rabbit corneal endothelial cells by trypan blue staining and quantitative electron probe X-ray microanalysis. Our results showed that the ionic content of potassium in cultured corneal endothelial cells tended to rise initially, but significantly decreased in cells in the fifth (and final) subculture, especially in comparison to cells in the fourth subculture (P subculture than in the fourth subculture (P subculture (P = 0.031). These data imply a remarkable decrease in the K/Na ratio from the fourth to the fifth subculture. Our microanalytical results, along with the morphological differences between cells in the last two subcultures, are compatible with an early phase of the preapoptotic process in the fifth subculture, and suggest that cells of the first four subcultures would be better candidates for tissue engineering.

  11. Scanning electron microscopical observation of an osteoblast/osteoclast co-culture on micropatterned orthopaedic ceramics

    Directory of Open Access Journals (Sweden)

    Mansur Halai

    2014-09-01

    Full Text Available In biomaterial engineering, the surface of an implant can influence cell differentiation, adhesion and affinity towards the implant. On contact with an implant, bone marrow–derived mesenchymal stromal cells demonstrate differentiation towards bone forming osteoblasts, which can improve osteointegration. The process of micropatterning has been shown to improve osteointegration in polymers, but there are few reports surrounding ceramics. The purpose of this study was to establish a co-culture of bone marrow–derived mesenchymal stromal cells with osteoclast progenitor cells and to observe the response to micropatterned zirconia toughened alumina ceramics with 30 µm diameter pits. The aim was to establish whether the pits were specifically bioactive towards osteogenesis or were generally bioactive and would also stimulate osteoclastogenesis that could potentially lead to osteolysis. We demonstrate specific bioactivity of micropatterns towards osteogenesis, with more nodule formation and less osteoclastogenesis compared to planar controls. In addition, we found that that macrophage and osteoclast-like cells did not interact with the pits and formed fewer full-size osteoclast-like cells on the pitted surfaces. This may have a role when designing ceramic orthopaedic implants.

  12. Pathological and electron microscopic studies on cold water disease among cultured rainbow trout (Oncorhynchus Mykiss Walbaum

    Directory of Open Access Journals (Sweden)

    Salah Mesalhy Aly

    2013-07-01

    Full Text Available The present study aims to investigate the etiology and pathogenesis of cold water disease among cultured rainbow trout (Oncorhynchus Mykiss Walbaum reared at low water temperature on a private farm, and propose preventive and control measures to prevent the recurrence of the disease and its spread to the neighboring farms or to other countries. The disease is caused by Flavobacterium psychrophilum and is characterized clinically by high mortality rates (25% with necrotizing skin and fin lesions. Septicemia with muscular and gill involvement is observed in severely affected cases. The histopathological and ultrastructure alterations in the infected trout explain the pathogencity of this microorganism in many organs other than skin and fins either directly by these bacteria or by its extracellular products, or indirectly via the hypoxia and ion imbalance that results from skin and gill damage. Although some antibiotics, such as trimethoprime, chloramin T and oxytetracycline, are effective on the causative agent, improvement in water quality, vaccination, increasing fish resistance and strict hygiene as well as quarantine measures would all help.

  13. Box Model of a Series of Salt Ponds, as Applied to the Alviso Salt Pond Complex, South San Francisco Bay, California

    Science.gov (United States)

    Lionberger, Megan A.; Schoellhamer, David H.; Shellenbarger, Gregory; Orlando, James L.; Ganju, Neil K.

    2007-01-01

    This report documents the development and application of a box model to simulate water level, salinity, and temperature of the Alviso Salt Pond Complex in South San Francisco Bay. These ponds were purchased for restoration in 2003 and currently are managed by the U.S. Fish and Wildlife Service to maintain existing wildlife habitat and prevent a build up of salt during the development of a long-term restoration plan. The model was developed for the purpose of aiding pond managers during the current interim management period to achieve these goals. A previously developed box model of a salt pond, SPOOM, which calculates daily pond volume and salinity, was reconfigured to simulate multiple connected ponds and a temperature subroutine was added. The updated model simulates rainfall, evaporation, water flowing between the ponds and the adjacent tidal slough network, and water flowing from one pond to the next by gravity and pumps. Theoretical and measured relations between discharge and corresponding differences in water level are used to simulate most flows between ponds and between ponds and sloughs. The principle of conservation of mass is used to calculate daily pond volume and salinity. The model configuration includes management actions specified in the Interim Stewardship Plan for the ponds. The temperature subroutine calculates hourly net heat transfer to or from a pond resulting in a rise or drop in pond temperature and daily average, minimum, and maximum pond temperatures are recorded. Simulated temperature was compared with hourly measured data from pond 3 of the Napa?Sonoma Salt Pond Complex and monthly measured data from pond A14 of the Alviso Salt-Pond Complex. Comparison showed good agreement of measured and simulated pond temperature on the daily and monthly time scales.

  14. Surface Sediments in Precooler Ponds 2, 4, and 5: March 2000

    Energy Technology Data Exchange (ETDEWEB)

    Dunn, D.L.

    2001-01-29

    Pond 2, Pond 4, and Pond 5 are inactive reactor cooling impoundments built in 1961 on the R-Reactor Effluent System in the east-central portion of the Department of Energy's Savannah River Site in Aiken, South Carolina. These precooler ponds are part of the Par Pond cooling water system and are considered part of the Par Pond operable unit. The intent was not to characterize the ponds, but to identify the maximum levels of contamination that could be exposed if the ponds are drained to remove the danger of dam failure.

  15. A mechanism that produces dichotomy in melt pond coverage in sea ice floes

    OpenAIRE

    Popović, Predrag; Abbot, Dorian S.

    2016-01-01

    Late in the melt season, sea ice floes in the Arctic have been observed to exhibit a large range in melt pond coverage, from heavily ponded to almost pond free. Some of these observations are consistent with a bimodal distribution in pond coverage with few intermediately ponded ice floes. We present a model for the evolution of melt ponds on sea ice floes in which conservation of hydrostatic balance in response to melt creates an unstable fixed point in pond coverage: if the initial pond cove...

  16. Supplemental effects of mixed ingredients and rice bran on the growth performance, survival and yield of Nile tilapia, Oreochromis niloticus reared in fertilized earthen ponds.

    Science.gov (United States)

    Limbu, S M; Shoko, A P; Lamtane, H A; Kishe-Machumu, M A; Joram, M C; Mbonde, A S; Mgana, H F; Mgaya, Y D

    2016-01-01

    Unaffordability of commercial feeds to semi-intensive Nile tilapia, Oreochromis niloticus farmers has led to reliance on supplemental feeding and fertilization for nutrition of their fish without a scientific basis. This study compared the growth, survival, condition factor and yield performance of O. niloticus fed on mixed ingredients (MI) and rice bran alone (RB) diets reared in fertilized earthen ponds in small scale farmers' ponds. The study also determined phytoplankton composition, biomass and abundance in the experimental ponds. Quadruplicate ponds were stocked with O. niloticus and African sharptooth catfish, Clarias gariepinus at a stocking ratio of 1:3. The initial mean weights of O. niloticus and C. gariepinus were 14.62 ± 0.61 and 20.34 ± 1.44 g respectively. The fish were fed on MI and RB diets with protein content of 184.74 and 126.06 g kg(-1) respectively for 270 days. The results showed that growth performance, survival rate and condition factor of O. niloticus were not affected by either feeding with MI or RB diet (p > 0.05). Moreover, there were no significant differences obtained in phytoplankton biomass and abundance in O. niloticus ponds fed on the two diets (p > 0.05). Furthermore, feeding O. niloticus either on MI or RB diet did not affect the net and gross fish yields (p > 0.05). The study revealed that the use of either MI or RB diet does not significantly affect the performance of O. niloticus cultured in semi-intensive earthen ponds where natural food organisms are an integral part of the culture system. Rice bran could be used for semi-intensive culture of O. niloticus in fertilized ponds to boost the production based on its availability and low cost.

  17. Eutrophic urban ponds suffer from cyanobacterial blooms: Dutch examples

    NARCIS (Netherlands)

    Waajen, Guido W. A. M.; Faassen, Elisabeth J.; Lurling, Miquel

    2014-01-01

    Ponds play an important role in urban areas. However, cyanobacterial blooms counteract the societal need for a good water quality and pose serious health risks for citizens and pets. To provide insight into the extent and possible causes of cyanobacterial problems in urban ponds, we conducted a surv

  18. Cannibalism in single-batch hybrid catfish production ponds

    Science.gov (United States)

    Hybrid catfish are more efficiently harvested by seining than are Channel Catfish. Due to that, and their faster growth, hybrids are typically produced in “single-batch” production systems, either in intensively-aerated commercial ponds or in split-pond systems. In either production system, hybrids...

  19. Performance evaluation of wastewater stabilization ponds in Yazd-Iran

    Directory of Open Access Journals (Sweden)

    Mahdi Farzadkia

    2014-11-01

    Full Text Available Background: Yazd waste stabilization pond facilities consist of three stabilization pond systems, module 1, module 2 and module 3 that AWSP module 1 has started its operation. The existing facilities have had several problems in their operation. The objectives of this research were to evaluate the performance of stabilization ponds in wastewater treatment of the city of Yazd, due to several problems in their operation, and to prepare a scheme of its upgrading, if necessary. Methods: During the period from December to June 2010, data analysis were carried out for both raw and treated wastewater. Results: Results of these investigations showed that the average effluent concentrations of Biochemical Oxygen Demand 5 (BOD5, Chemical Oxygen Demand (COD and Suspended Solid (SS taken from anaerobic pond and secondary facultative ponds of module 1 were 306.9, 135.18, 139.75 and 136.75, 69.025, 136.5 mg/L, respectively. Conclusion: These results indicated that the effluent of the anaerobic pond of module 1 was complied with the Iranian treated wastewater standards for agricultural reuse in terms of BOD5 and COD concentrations; hence the secondary facultative ponds could be changed to other primary facultative ponds in order to increase the capacity of wastewater treatment plant.

  20. Wind Effects on Retention Time in Highway Ponds

    DEFF Research Database (Denmark)

    Bentzen, Thomas Ruby; Larsen, Torben; Rasmussen, Michael R.

    2007-01-01

    The paper presents results from an experimental and numerical study of wind-induced flows and transportation patterns in highway wet detention ponds. The study presented here is part of a general investigation on road runoff and pollution in respect to wet detention ponds. The objective is to eva......-uniform wind field distributions are not significant to this study....

  1. Biological removal of algae in an integrated pond system

    CSIR Research Space (South Africa)

    Meiring, PGJ

    1995-01-01

    Full Text Available A system of oxidation ponds in series with a biological trickling filter is described. It was known that this arrangement was incapable of reducing effectively the levels of algae present in the pond liquid even though nitrification was effected...

  2. Effects of riparian buffers on hydrology of northern seasonal ponds

    Science.gov (United States)

    Randall K. Kolka; Brian J. Palik; Daniel P. Tersteeg; James C. Bell

    2011-01-01

    Although seasonal ponds are common in northern, glaciated, forested landscapes, forest management guidelines are generally lacking for these systems. The objective of this study was to determine the effect of riparian buffer type on seasonal pond hydrology following harvest of the adjacent upland forest. A replicated block design consisting of four buffer treatments...

  3. Rabbit droppings as an organic fertilizer in earthen ponds, to ...

    African Journals Online (AJOL)

    cntaganda

    Nine earthen ponds of 400 m2 were stocked with mixed sexes of Nile tilapia. Oreochromis niloticus ... the effect of rabbit dung on the quality of fish pond water, and the growth ... The author recommended, for extension purposes, a load-rate of 60 ...... dynamics model for the ecological analysis of integrated aquaculture/ ...

  4. STORMWATER TREATMENT: WET/DRY PONDS VS. CONSTRUCTED WETLANDS

    Science.gov (United States)

    Extant data were used to assess the relative effectiveness of ponds vs. wetland-type BMPs. Compared to wet ponds, wetlands tended toward higher constituent concentrations in effluent, were inefficient at nitrogen removal, and appeared to preferentially retain phosphorous. These d...

  5. Heat recovery from ground below the solar pond

    NARCIS (Netherlands)

    Ganguly, S.; Date, Abhijit; Akbarzadeh, Aliakbar

    2017-01-01

    The method of heat recovery from the ground below solar ponds is investigated in the present brief note. Solar ponds lose considerable amount of heat from its bottom to the ground due to temperature gradient between them. This waste heat from ground, which is at different temperature at different

  6. ELECTRONIC COLLABORATION ACROSS CULTURES IN A WEB-BASED PROJECT FOR ENGLISH WRITING INSTRUCTION

    Directory of Open Access Journals (Sweden)

    George C.K. Jor

    2000-01-01

    Full Text Available The paper highlights the importance of experimentation and an innovative approach to English language writing instruction with the help of information communication technology (ICT or IT. First, it describes the local situation of English language teaching at The Chinese University of Hong Kong (CUHK. Then, it summarizes the development of IT proficiency and student-led collaborative learning groups at CUHK. Third, it reports on an international Web-based writing project involving six collaborating schools in different parts of the world including China, the United States, Indonesia, and Hong Kong in the year 1999-2000. In the report, the author-presenter will share with the audience a new ELT course development titled "English Online: Writing on the Web." He will explain the course objectives, the background of participating classes, the Web Course Tools (WebCT, the design of the project, the evaluation of course effectiveness and the outcome of the new curricular initiative. Finally, the paper presents a summary of a practical guide to electronic collaboration and some of the lessons the writer has learnt in five years' experience of participant-observation in English teaching practice using the Web.

  7. 2101-M Pond hydrogeologic characterization report

    Energy Technology Data Exchange (ETDEWEB)

    Chamness, M.A.; Luttrell, S.P.; Bates, D.J.; Martin, W.J.

    1990-09-01

    This report documents information collected by the Pacific Northwest Laboratory {sup (a)} at the request of Westinghouse Hanford Company. Presented in this report is the interpretation of the hydrogeologic environment at the 2101-M Pond, located in the 200-East Area of the Hanford Site. This information and its accompanying interpretation were derived from sampling and testing activities associated with the installation of four ground-water monitoring wells, in addition to data gathered from several previously existing wells. The new monitoring wells were installed as part of a groundwater monitoring program initiated in 1988. The four new monitoring wells were installed around the 2101-M Pond between May 23 and August 27, 1988. Geologic sampling, aquifer testing, and initial ground-water sampling were performed during the installation of these wells. Laboratory analyses of the sediment samples for particle size, calcium carbonate content, and selected natural and contaminant constituents were performed. A full year of quarterly ground-water sampling and the first statistical analysis of background and downgradient data have also been performed. 112 refs., 49 figs., 18 tabs.

  8. Salton Sea Project, Phase 1. [solar pond power plant

    Science.gov (United States)

    Peelgren, M. L.

    1982-01-01

    A feasibility study was made for a salt gradient solar pond power plant in or near the Salton Sea of California. The conclusions support continuance 5-MWe proof-of-concept experiment, and ultimate construction by an electric utility company of a 600-MWe plant. The Solar Pond concept would be an environmental benefit to the Salton Sea by reversing the increasing salinity trend. The greatest cost drivers are the lake dike construction and pond sealing. Problems to be resolved include method of brine production from Salton Sea water for the first unit (which requires evaporation pond area and time), the high turbidity and color content of the Salton Sea water (which requires pretreatment), and other questions related to pond permeability, bio-activity and soil/brine chemical reactions. All technical and environmental problems appear solvable and/or manageable if care is taken in mitigating impacts.

  9. The evaporation from ponds in the French Midwest

    Directory of Open Access Journals (Sweden)

    Mohammad AL DOMANY

    2013-12-01

    Full Text Available This research shows the results of a study about evaporation in five ponds in the Midwest of France. To realize this study we used climate data from the meteorological station of the Limoges-Bellegarde airport and the data of a weather station installed by us near one of the ponds. We used eight different methods to calculate the evaporation rate and we modified the Penman-Monteith method by replacing the air temperature by water temperature. To understand the role of ponds in water loss through evaporation, we proposed a hypothesis that says : if the pond did not exist, what results would we get? Based on this hypothesis we calculated the potential evapotranspiration rate taking into account the percentage of interception by vegetation. In conclusion, this study indicates that the ponds in the French Midwest present a gain of water

  10. Phytoremediation efficiency of Eichhornia crassipes in fly ash pond.

    Science.gov (United States)

    Pandey, Vimal Chandra

    2016-01-01

    The present study was focused on field research to examine the phytoremediation potential of naturally grown Eichhornia crassipes in fly ash (FA) pond. Field results indicate the efficiency of E. crassipes for remediation of heavy metals from FA pond. The bioconcentration factor trend was Cr (3.75) > Cu (2.62) > Cd (1.05), and Cu (1.35) in root and stem, respectively. The survival and abundance growth of E. crassipes in the circumstance of heavy metal enriched FA pond is another highlight of the present research that reveals its toxitolerant characteristics. Thus, this lesson on phytoremediation proved that E. crassipes is a potential accumulator of Cu, Cr, and Cd from FA ponds and is a promising species for FA pond's remediation globally.

  11. Emissions from Produced Water Treatment Ponds, Uintah Basin, Utah, USA

    Science.gov (United States)

    Mansfield, M. L.; Lyman, S. N.; Tran, H.; O'Neil, T.; Anderson, R.

    2015-12-01

    An aqueous phase, known as "produced water," usually accompanies the hydrocarbon fluid phases that are extracted from Earth's crust during oil and natural gas extraction. Produced water contains dissolved and suspended organics and other contaminants and hence cannot be discharged directly into the hydrosphere. One common disposal method is to discharge produced water into open-pit evaporation ponds. Spent hydraulic fracturing fluids are also often discharged into the same ponds. It is obvious to anyone with a healthy olfactory system that such ponds emit volatile organics to the atmosphere, but very little work has been done to characterize such emissions. Because oil, gas, and water phases are often in contact in geologic formations, we can expect that more highly soluble compounds (e.g., salts, alcohols, carbonyls, carboxyls, BTEX, etc.) partition preferentially into produced water. However, as the water in the ponds age, many physical, chemical, and biological processes alter the composition of the water, and therefore the composition and strength of volatile organic emissions. For example, some ponds are aerated to hasten evaporation, which also promotes oxidation of organics dissolved in the water. Some ponds are treated with microbes to promote bio-oxidation. In other words, emissions from ponds are expected to be a complex function of the composition of the water as it first enters the pond, and also of the age of the water and of its treatment history. We have conducted many measurements of emissions from produced water ponds in the Uintah Basin of eastern Utah, both by flux chamber and by evacuated canister sampling with inverse modeling. These measurements include fluxes of CO2, CH4, methanol, and many other volatile organic gases. We have also measured chemical compositions and microbial content of water in the ponds. Results of these measurements will be reported.

  12. DOMINANT FACTORS AFFECTING SEAWEED (Gracilaria verrucosa PRODUCTION IN ACID SULFATE SOILS-AFFECTED PONDS OF LUWU REGENCY, INDONESIA

    Directory of Open Access Journals (Sweden)

    Akhmad Mustafa

    2010-12-01

    Full Text Available Most of brackish water ponds used for seaweed (Gracilaria verrucosa culture in Luwu Regency, South Sulawesi, Indonesia are constructed on acid sulfate soil. Despite this inevitable condition, opportunities remain open to increase the seaweed production. The research was conducted to study the dominant factors that affect the seaweed production in ASS-affected ponds of Luwu Regency. As a dependent variable in this research is seaweed production. Independent variables were grouped into: (a farmer status factor, consisting of 9 variables; (b pond condition factor, consisting of 8 variables; (c pond management factor, consisting of 29 variables; (d soil quality factor, consisting of 17 variables and (e water quality factor, consisting of 11 variables. Multiple regression with dummy variable was used to analyze the data in prediction dependent variable. Results show that the average of seaweed production in ASS-affected pond of Luwu Regency is 11,000 kg dry/ha/year. Seaweed production can be increased through: (a decreasing dosage of urea and KCl and increasing dosage and frequency of fertilizer containing phosphate; (b increasing water depth in the pond and decreasing percentage of water exchange,(c conducting remediation to increase the soil pH and decreasing the concentration of Fe in the water, (d increasing stocking density of milkfish to decrease the epiphyte population and (e increasing the frequency of the farmer to attend trainings.

  13. Biodiesel from wastewater: lipid production in high rate algal pond receiving disinfected effluent.

    Science.gov (United States)

    Assemany, Paula Peixoto; Calijuri, Maria Lucia; do Couto, Eduardo de Aguiar; Santiago, Aníbal Fonseca; Dos Reis, Alberto José Delgado

    2015-01-01

    The production of different species of microalgae in consortium with other micro-organisms from wastewaters may represent an alternative process, to reduce the costs, for obtaining biofuels. The aim of this study was to evaluate the influence of pre-ultraviolet disinfection (UV) in the production of lipids from biomass produced in high rate ponds. Two high rate algal ponds were evaluated: a pond that received domestic sewage without disinfection and the other receiving domestic sewage previously disinfected by UV radiation (uvHRAP). The UV disinfection did not lead to significant differences in fatty acid profile and total lipid productivities, although it increased algal biomass concentration and productivity as well as lipid content. Moreover, the overall biomass concentrations and productivities decreased with the UV disinfection, mostly as a consequence of a loss in bacterial load. We thus conclude that uvHRAP disinfection may represent a potential strategy to promote the cleaner and safer growth of algal biomass when cultivated in consortium with other micro-organisms. Mainly regarding the use of wastewater as culture medium, together with a cheaper production of lipids for biodiesel, pre-disinfection may represent an advance since extraction costs could be significantly trimmed due to the increase in lipid content.

  14. Par Pond phytoplankton in association with refilling of the pond: Final Report for sampling from February 1995 -- September 1996

    Energy Technology Data Exchange (ETDEWEB)

    Wilde, E.W.; Johnson, M.A.; Cody, W.C.

    1996-12-31

    This report describes the results of phytoplankton analyses from Par Pond samples collected between February 1995 and September 1996. The principal objective of the study was to determine the effect of refilling of Par Pond following repair of the dam on the phytoplankton community. Algal blooms are often responsible for fish kills and other detrimental effects in ponds and lakes, and it was postulated that decaying vegetation from formerly exposed sediments might trigger algal blooms that could result in fish kills in Par Pond following the refill. Sporadic algal blooms involving blue-green algae were detected, especially during the summer of 1996. However, the data derived from the study demonstrates that overall, the refilling effort caused no significant negative impact to the pond attributable to phytoplankton dynamics.

  15. Influence of Different DNA Extraction Methods on Microbial Diversity PCR-DGGE Detection of Culture Pond Sendiment%DNA不同提取方法对养殖池塘底泥细菌多样性PCR-DGGE检测的影响

    Institute of Scientific and Technical Information of China (English)

    王宇; 林文辉; 王亚军; 毕晔; 石存斌; 吴淑勤

    2009-01-01

    应用PCR-DGGE技术研究了养殖池塘底泥中细菌DNA 5种提取方法对细菌多样性检测的影响.结果显示:(1)DNA粗提液中腐殖酸与蛋白的纯度无正相关;(2)5种方法提取的DNA粗提液经过纯化后进行PCR均取得良好结果;(3)采用复合破壁方法提取养殖池塘底泥细菌DNA有利于显示细菌多样性;(4)DNA提取方法是影响池塘底泥细菌多样性PCR-DGGE结果的关键因素,与DNA的产量、纯度关系甚微;(5)5种方法相似性高达0.79,在对养殖池塘底泥细菌多样性进行粗略分析时均可使用;(6)本试验中,基于改进的Martin-Laurent法是用于养殖池塘底泥细菌多样性PCR-DGGE研究的较好的总DNA提取方法.%In this research, PCR - DGGE technique was used for studying five different extraction methods of microbial DNA of the pond sediment in difference of microbial diversities. The purpose is to try to find extraction methods of DNA which can be best used to objectively reflect the diversities and advantages of the bacteria of the pond sediment, and to evaluate comprehensively the five extraction methods. The results showed that: DNA in the crude extract of two humic acids and protein purity is of no positive correlation; the crude DNA extract of the five extraction methods, after purification, yields good results with PCR; broken composite method is used in the extraction of microbial DNA in the sediment ponds, helping enhance microbial diversity; DNA extraction method is the key factor of pond sediment microbial diversity by DGGE, and the diversity has poor relationship with the output and size of DNA; the similarity of the five ways is as high as 0.79, so it can be substituted for one another to conduct a rough analysis of mierobia] diversity; the improved Martin-Laurent Act is a better DNA extraction method for PCR -DGGE microbial diversity study in sediment ponds.

  16. Trapping carbon in small ponds and wetlands

    Science.gov (United States)

    Quinton, J. N.; Ockenden, M. C.; Deasy, C.; Favaretto, N.

    2012-04-01

    There is no doubt that carbon (C) is on the move. Recent estimates have suggested that the global sediment flux in agricultural landscapes due to water and tillage erosion is 35±10 Pg C y-1. Some of this C is oxidised and lost to the atmosphere, other material may be deposited and burried in colluvium and some may be delivered through both surface and subsurface flow paths to surface waters. In many agricultural landscapes these surface waters may take the form of small ponds and wetlands (field wetlands). In this paper we explore the potential of field wetlands to trap particulate C and influence the fate of dissolved organic carbon within the context of a small agricultural catchments in England. Since 2008 the mitigation options for phosphorus and sediment project (MOPS) has established ten monitored field wetlands across three catchments in the UK at Crake Trees, Cumbria (silt soils, rainfall 1500 mm y-1), Whinton Hill Cumbria (sandy soils, rainfall 1200 mm y-1), Newton Rigg, Cumbria (Silt soils, rainfall c1200 mm y-1) and Loddington, Leicestershire (Clay soils, rainfall 650 mm y-1). Although originally designed to capture sediment and phosphorus, their potential for influencing catchment scale C dynamics is becoming apparent. The C contents of sediments from the three catchments are typically in the range of 1.8 - 3.0% at Crake Trees Catchment, 2.5 to 9% at Whinton Hill and 2.0 to 3.1 % at Crake Trees. At the high rainfall sites the wetlands trap upwards of 20 t y-1 of sediment equating to several hundred kilograms of C. There is also some evidence that the ponds and wetlands may influence DOC, with DOC concentrations falling from approximately 35 mg l-1 to 15 mg l-1 at the Whinton Hill site as water passes through a series of field wetlands. In this paper we will present data from the last two years of monitoring and consider the wider implications for C sequestration by ponds and wetlands in agricultural landscapes.

  17. 高密度养殖下革胡子鲶生长激素mRNA表达的半定量分析%Semi-quantitative Analysis of Growth Hormone(GH) mRNA Expression of Clarias gariepinus in High Density Pond Culture

    Institute of Scientific and Technical Information of China (English)

    王晓梅; 戴伟; 郭永军; 陈承勋; 李娜; 张茂群

    2011-01-01

    以β-肌动蛋白(β-actin)mRNA的表达量作为内标,应用半定量RT-PCR法,对高密度养殖条件下不同月龄革胡子鲶垂体生长激素(Growth hormone,GH)mRNA的相对表达量进行分析.结果显示:3.5,5,6.5月龄试验鱼的GH mRNA的相对表达量分别为3.612~5.965,2.929~4.556和1.360~1.821;平均相对表达量分别为4.346±0.656 0,3.649±0.568 4和1.575±0.135 5.上述数据经方差分析得出,革胡子鲶任意两个不同月龄之间GH mRNA相对表达量的差异达到1%的显著水平.Duncan氏多重比较结果显示,3.5,5月龄试验鱼垂体GH mRNA的平均相对表达量差异不显著,但均极显著高于6.5月龄.%Using β-actin mRNA expression quantity as an internal reference,the differences of growth hormone (GH) mRNA expression in pituitary of Clarias gariepinus in high density pond culture at different months old were analyzed with the employment of semi-quantitative RT-PCR method. The relative expression quantity of GH mRNA of individuals at 3.5,5 and 6.5 months old were 3. 612 - 5. 965,2. 929 - 4. 556 and 1. 360 - 1. 821 ,respectively, while the mean relative expressions were 4.346 ±0.656 0,3. 649 ±0.568 4 and 1. 575 ± 0. 135 5 separately for 3.5,5 and 6.5 months old. The variance analysis indicated that the significant differences reached 1% in the relative expression level of the GH mRNA between any two months old. The Duncan's multiple comparison showed that the differences of GH mRNA expression between that at 3.5 and 6.5 months old as well as that at 5 and 6.5 months old were extremely significant,but there was no difference of GH mRNA expression between that at 3.5 and 5 months old.

  18. Dissemination of cultured fishery technology by extension agents in ...

    African Journals Online (AJOL)

    Dissemination of cultured fishery technology by extension agents in Oyo state, ... technology to the fish farmers, the source of information and kind of training acquired. ... adoption over concrete ponds due to variation in the cost of construction.

  19. Fate of copper in intensive shrimp farms: bioaccumulation and deposition in pond sediments

    Directory of Open Access Journals (Sweden)

    LD. Lacerda

    Full Text Available We present the distribution of Cu in water, sediments and biomass from intensive shrimp (Litopenaeus vannamei Boone, 1931 farming in northeastern Brazil. The results show no difference in dissolved Cu concentrations between waters entering and leaving the ponds. However, there was a large export of particulate Cu to adjacent environments, showed by extremely high particulate (112 µg.L-1 Cu concentrations in draining waters. Copper concentrations in the bottom sediments of the pond varied with depth from 10 to 20 µg.g-1, being 5 to 7 times higher than the local background. Pond management procedures result in a peculiar vertical distribution of Cu with peak values occurring at sub-surface depths in pond bottom sediments. Bioavailable Cu reaches about 20% of the total Cu content in sediments. Notwithstanding the relatively high Cu bioavailability, concentrations in shrimp muscle (23.2 to 63.4 µg.g-1 d.w. were similar to reported values for reared and natural L. vannamei populations, and much lower than acceptable maximum limits for human consumption. Concentrations in the exoskeleton were always higher than in muscle. Increasing Cu mass, and to a lesser extent Cu concentrations in muscle tissues, occurred simultaneously to a decrease in Cu mass and concentrations in the exoskeleton and vice versa, suggesting a dynamical exchange of Cu between the two compartments. Although Cu fate in intensive shrimp culture does not result in increasing Cu exposure to consumers, the activity is an important source of this metal to adjacent ecosystems, in particular in the pristine environments where most aquaculture activities in NE Brazil takes place.

  20. Thiohalocapsa marina sp. nov., from an Indian marine aquaculture pond.

    Science.gov (United States)

    Anil Kumar, P; Srinivas, T N R; Thiel, V; Tank, M; Sasikala, Ch; Ramana, Ch V; Imhoff, J F

    2009-09-01

    A spherical-shaped, phototrophic, purple sulfur bacterium was isolated in pure culture from anoxic sediment in a marine aquaculture pond near Bheemli (India). Strain JA142T is Gram-negative and non-motile. It has a requirement for NaCl (optimum of 2% and maximum of 6% w/v NaCl). Intracellular photosynthetic membranes are of the vesicular type. In vivo absorption spectra indicate the presence of bacteriochlorophyll a and carotenoids of the okenone series as photosynthetic pigments. Phylogenetic analysis on the basis of 16S rRNA gene sequences showed that strain JA142T is related to halophilic purple sulfur bacteria of the genera Thiohalocapsa and Halochromatium, with the highest sequence similarity to Thiohalocapsa halophila DSM 6210T (97.5%). Morphological and physiological characteristics differentiate strain JA142T from other species of the genera Halochromatium and Thiohalocapsa. Strain JA142T is sufficiently different from Thiohalocapsa halophila based on 16S rRNA gene sequence analysis and morphological and physiological characteristics to allow the proposal of a novel species, Thiohalocapsa marina sp. nov., with the type strain JA142T (=JCM 14780T=DSM 19078T).

  1. Accumulation of Pollutants in Highway Detention Ponds

    DEFF Research Database (Denmark)

    Bentzen, Thomas Ruby

    This PhD study deals with issues related to water and pollutant transport from highway surfaces caused by rain. It is essential in the study to apply methods and models in which improvements in relation to removal of pollutants can be identified and to be able to predict the yearly discharges...... of heavy metals and polycyclic aromatic hydrocarbons from an arbitrary detention pond to the natural environment. The present thesis is a part of a co-operation between the Danish Road Directorate (Vejdirektoratet) and Aalborg University and is founded in the Danish construction act for new highways...... single rain event. From the hindcast results it is possible to calculate mean water and pollutant loads. This method is commonly used in urban drainage systems for capacity analysis or for prediction of CSO's. The challenge is to develop a simplified and still accurate description of flow and transport...

  2. Environmental selection of planktonic methanogens in permafrost thaw ponds

    Science.gov (United States)

    Crevecoeur, Sophie; Vincent, Warwick F.; Lovejoy, Connie

    2016-08-01

    The warming and thermal erosion of ice-containing permafrost results in thaw ponds that are strong emitters of methane to the atmosphere. Here we examined methanogens and other Archaea, in two types of thaw ponds that are formed by the collapse of either permafrost peat mounds (palsas) or mineral soil mounds (lithalsas) in subarctic Quebec, Canada. Using high-throughput sequencing of a hypervariable region of 16S rRNA, we determined the taxonomic structure and diversity of archaeal communities in near-bottom water samples, and analyzed the mcrA gene transcripts from two sites. The ponds at all sites were well stratified, with hypoxic or anoxic bottom waters. Their archaeal communities were dominated by Euryarchaeota, specifically taxa in the methanogenic orders Methanomicrobiales and Methanosarcinales, indicating a potentially active community of planktonic methanogens. The order Methanomicrobiales accounted for most of the mcrA transcripts in the two ponds. The Archaeal communities differed significantly between the lithalsa and palsa ponds, with higher alpha diversity in the organic-rich palsa ponds, and pronounced differences in community structure. These results indicate the widespread occurrence of planktonic, methane-producing Archaea in thaw ponds, with environmental selection of taxa according to permafrost landscape type.

  3. CO2 Efflux from Shrimp Ponds in Indonesia

    Science.gov (United States)

    Sidik, Frida; Lovelock, Catherine E.

    2013-01-01

    The conversion of mangrove forest to aquaculture ponds has been increasing in recent decades. One of major concerns of this habitat loss is the release of stored ‘blue’ carbon from mangrove soils to the atmosphere. In this study, we assessed carbon dioxide (CO2) efflux from soil in intensive shrimp ponds in Bali, Indonesia. We measured CO2 efflux from the floors and walls of shrimp ponds. Rates of CO2 efflux within shrimp ponds were 4.37 kg CO2 m−2 y−1 from the walls and 1.60 kg CO2 m−2 y−1 from the floors. Combining our findings with published data of aquaculture land use in Indonesia, we estimated that shrimp ponds in this region result in CO2 emissions to the atmosphere between 5.76 and 13.95 Tg y−1. The results indicate that conversion of mangrove forests to aquaculture ponds contributes to greenhouse gas emissions that are comparable to peat forest conversion to other land uses in Indonesia. Higher magnitudes of CO2 emission may be released to atmosphere where ponds are constructed in newly cleared mangrove forests. This study indicates the need for incentives that can meet the target of aquaculture industry without expanding the converted mangrove areas, which will lead to increased CO2 released to atmosphere. PMID:23755306

  4. MERCURY CONTENT IN BOTTOM SEDIMENTS OF MID-FIELD PONDS

    Directory of Open Access Journals (Sweden)

    Kamil Szydłowski

    2016-09-01

    Full Text Available Two mid-field ponds located in the agricultural catchment was chosen for the investigations. Total of 24 samples of bottom sediments were collected. The samples were taken from sediment layers: 0–5 (W1, 5–10 (W2, 10–20 (W3 and 20–30 (W4 cm, with three points at once during the 2014 winter period. Mercury content in the samples was determined by analyzer AMA 254. Higher pH (active acidity was recorded in sediments in pond located in a rural park than pond located within agricultural crops. Bottom sediment in mid-field pond (No. 1 had higher values of organic carbon averaging 22.70% than in the pond located in a rural park (No. 2, where organic carbon content averaged 4.59%. The mercury content in bottom sediments ranged from 0.02 to 0.41 mg ⋅ kg-1. The examined sediments were classified (at points P1, P2, P3 and P4 as uncontaminated sediments (Class I and at points S1 and S2 were classified as moderately polluted sediments (Class II. Bottom sediments classified as class I and II can be disposed in the aquatic and terrestrial environments. Mercury concentrations in samples collected from both banks of the pond No. 1 and 2 differ significantly (Tukey test p ≤ 0.05 than those in the samples collected from central part of the ponds. Chemical analysis of the individual layers of bottom sediments in ponds showed that the largest accumulation of mercury occurred in a layer W1 (0–5 cm in pond No. 2 (at point S2.

  5. GROWING NIPA PALM FOR RESTORATION OF ABANDONED SHRIMP PONDS

    Institute of Scientific and Technical Information of China (English)

    Noparat Bamroongrugsa; Chorthip Purintavarakul

    2006-01-01

    Rapid increase in the production of marine shrimps in the coastal zone has resulted in large - scale conversion of mangrove forests to shrimp ponds. Productions of the shrimps in some regions have been unstable. Consequently, a number of ponds are left idle. Restoring environmental conditions within the pond site by planting a suitable mangrove species considered an option. The experiment herein was carried out to explore the effect of planting methods on growth of Nipa palm in abandoned shrimp ponds in the Southern Thailand. Economically, coastal villagers in this area earn their income from the palm in several ways, the most importantly in Nipa sugar production. Most seedlings were planted on top of furrows were constructed in the pond to avoid flooding, except for some seedlings which were planted in the pond base where additional pond sludge were slightly filled up to compare their growth rates. The results showed that planting seedlings with attached rhizomes had the best growth rate and without seedling death at 14 months after planting. At this stage, however, the height of seedlings grown from the fallen fruits was similar to those growth from bare rooted seedlings (70 cm tall). Also, seedling mortality was not observed when growth from fallen fruits whereas about6% mortality was experienced by the bare rooted ones. Among the bare rooted seedling treatments, however no significant differences in growth rates were found when applying the soil with chemical fertilizers or farm manure or liming with CaCO3. In addition, it was found that seedling growth measured at 40 months after planting for those growths in pond base was almost 100% greater than those grown on the furrows. Therefore, this finding may be applied for the restoration of abandoned shrimp ponds by growing Nipa palm.

  6. Monthly and diurnal variations of limnological conditions of two ponds

    Directory of Open Access Journals (Sweden)

    AKM Fazlur Rahaman

    2017-06-01

    Full Text Available A study on monthly and diurnal changes of limnological conditions of two ponds was conducted in the Bangladesh Agricultural University campus, Mymensingh. The research work was performed by studying the limnological parameters such as transparency, temperature, dissolved oxygen, free carbon dioxide, pH, total alkalinity, nitrate-nitrogen, phosphate-phosphorus and plankton. Diurnal variations of physico-chemical factors were studied fortnightly at 6 hrs intervals at 6 a.m., 12 noon, 6 p.m. and 12 midnight. The amounts of transparency, dissolved oxygen and pH were higher during winter months than in summer months in both the ponds. Transparency, water temperature, total alkalinity, NO3-N and PO4-P were higher during summer months than in winter months in both the ponds. But the amount of free carbon dioxide was higher during winter months than in summer months in pond 1 while in pond 2 the amount of free carbon dioxide was higher during summer months than in winter months. Qualitative and quantitative monthly variations of phytoplankton and zooplankton were observed in both the ponds during the study period. The highest amount of dissolved oxygen, pH and total alkalinity were recorded at 6 p.m. and the lowest amounts of those at 6 a.m. in both the ponds. The highest temperature was recorded at 12 noon and the lowest at 12 midnight. But the highest amount of free carbon dioxide was recorded at 6 a.m. and the lowest at 6 p.m. in both the ponds. All the factors showed appreciable diel variations throughout the study period, which indicate that the ponds are productive.

  7. Removal of Fecal Indicators, Pathogenic Bacteria, Adenovirus, Cryptosporidium and Giardia (oo)cysts in Waste Stabilization Ponds in Northern and Eastern Australia.

    Science.gov (United States)

    Sheludchenko, Maxim; Padovan, Anna; Katouli, Mohammad; Stratton, Helen

    2016-01-02

    Maturation ponds are used in rural and regional areas in Australia to remove the microbial loads of sewage wastewater, however, they have not been studied intensively until present. Using a combination of culture-based methods and quantitative real-time PCR, we assessed microbial removal rates in maturation ponds at four waste stabilization ponds (WSP) with (n = 1) and without (n = 3) baffles in rural and remote communities in Australia. Concentrations of total coliforms, E. coli, enterococci, Campylobacter spp., Salmonella spp., F+ RNA coliphage, adenovirus, Cryptosporidium spp. and Giardia (oo) cysts in maturation ponds were measured at the inlet and outlet. Only the baffled pond demonstrated a significant removal of most of the pathogens tested and therefore was subjected to further study by analyzing E. coli and enterococci concentrations at six points along the baffles over five sampling rounds. Using culture-based methods, we found a decrease in the number of E. coli and enterococci from the initial values of 100,000 CFU per 100 mL in the inlet samples to approximately 1000 CFU per 100 mL in the outlet samples for both bacterial groups. Giardia cysts removal was relatively higher than fecal indicators reduction possibly due to sedimentation.

  8. Ponded Impact Melt Dynamics and its Effects on Pond Surface Morphology - Insights from King Crater

    Science.gov (United States)

    Ashley, J. W.; DiCarlo, N.; Enns, A. C.; Hawke, B. R.; Hiesinger, H.; Robinson, M. S.; Sato, H.; Speyerer, E.; van der Bogert, C.; Wagner, R.; Young, K. E.; LROC Science Team

    2011-12-01

    King crater is a 77-km diameter impact feature located at 5.0°N and 120.5°E on the lunar farside. Previous work delimited King crater with an asymmetric distribution of ejecta that includes a large impact melt pond (~385 square kilometer surface area), located in nearby Al-Tusi crater. The pond provides an opportunity to study the behavior of a large impact melt deposit. The Lunar Reconnaissance Orbiter Camera (LROC) Wide Angle Camera (WAC) and Narrow Angle Cameras (NAC) [1] imaged King crater from a nominal 50 km altitude at pixel scales of 100 meters and up to 0.5 meters, respectively providing the means to create geologic maps for the region. Digital terrain/elevation models (DTMs) were derived [2] from both WAC and NAC images for the area, and supplemented the mapping effort. The high-resolution (50 cm/p) NAC images show fine details within the Al-Tusi melt pond that raise questions about melt pond dynamics and evolution. These include both positive- and negative-relief features, anomalous crater morphologies, and flow features that show variable degrees of melt viscosity. WAC DTM processing reveals a horizontal and relatively flat (at the 20 m contour interval) pond, demonstrating that an equipotential surface was achieved during initial melt accumulation. The NAC DTM shows kilometer-scale zones of topographic down-warping within the 20 m contour interval. The perimeters of these depressed areas show moderate to high spatial correlation with the occurrence of negative relief features (~10 to 100 m in length). Such sagging may have occurred as the result of contraction and/or compaction within the melt both during and following cooling, with the negative relief features resulting from consequent structural failure and separation of the thickening surface crust. The variability in the degree of contraction/compaction may be explained by the presence of underlying hummocky ejecta deposits (which probably also explains the positive relief features) emplaced by

  9. Performance of municipal waste stabilization ponds in the Canadian Arctic

    DEFF Research Database (Denmark)

    Ragush, Colin M.; Schmidt, Jordan J.; Krkosek, Wendy H.

    2015-01-01

    The majority of small remote communities in the Canadian arctic territory of Nunavut utilize waste stabilization ponds (WSPs) for municipal wastewater treatment because of their relatively low capital and operational costs, and minimal complexity. New national effluent quality regulations have been...... implemented in Canada, but not yet applied to Canada’s Arctic due to uncertainty related to the performance of current wastewater treatment systems. Waste stabilization pond (WSP) treatment performance is impacted by community water use, pond design, and climate. The greatest challenge arctic communities...

  10. Arctic melt ponds and bifurcations in the climate system

    CERN Document Server

    Sudakov, Ivan; Golden, Kenneth M

    2014-01-01

    Understanding how sea ice melts is critical to climate projections. In the Arctic, melt ponds that develop on the surface of sea ice floes during the late spring and summer largely determine their albedo $-$ a key parameter in climate modeling. Here we explore the possibility of a simple sea ice climate model passing through a bifurcation point $-$ an irreversible critical threshold as the system warms, by incorporating geometric information about melt pond evolution. This study is based on a nonlinear phase transition model for melt ponds, and bifurcation analysis of a simple climate model with ice - albedo feedback as the key mechanism driving the system to a potential bifurcation point.

  11. Limnological database for Par Pond: 1959 to 1980

    Energy Technology Data Exchange (ETDEWEB)

    Tilly, L.J.

    1981-03-01

    A limnological database for Par Pond, a cooling reservoir for hot reactor effluent water at the Savannah River Plant, is described. The data are derived from a combination of research and monitoring efforts on Par Pond since 1959. The approximately 24,000-byte database provides water quality, primary productivity, and flow data from a number of different stations, depths, and times during the 22-year history of the Par Pond impoundment. The data have been organized to permit an interpretation of the effects of twenty years of cooling system operations on the structure and function of an aquatic ecosystem.

  12. Description of work for 216-U-Pond test pits

    Energy Technology Data Exchange (ETDEWEB)

    Kelty, G.G.

    1993-08-11

    This description of work (DOW) details the field activities associated with the test pit excavation and soil sampling at the 216- U-10 Pond (U-10 Pond) in the 200 West Area and will serve as a field guide for those performing the work. It will be used in conjunction with the 200-UP-2 Resource Conservation and Recovery Act of 1976 (RCRA) Facility Investigation/Corrective Measures Study (DOE-RL 1993a, [LFI]) and Site Characterization Manual (WHC 1988a). Test pits will be constructed to characterize the vertical extent of contaminants in sediments within and beneath the former U-10 pond.

  13. The prediction of bacteria type and culture growth phase by an electronic nose with a multi-layer perceptron network

    Science.gov (United States)

    Gardner, J. W.; Craven, M.; Dow, C.; Hines, E. L.

    1998-01-01

    An investigation into the use of an electronic nose to predict the class and growth phase of two potentially pathogenic micro-organisms, Eschericha coli ( E. coli) and Staphylococcus aureus ( S. aureus), has been performed. In order to do this we have developed an automated system to sample, with a high degree of reproducibility, the head space of bacterial cultures grown in a standard nutrient medium. Head spaces have been examined by using an array of six different metal oxide semiconducting gas sensors and classified by a multi-layer perceptron (MLP) with a back-propagation (BP) learning algorithm. The performance of 36 different pre-processing algorithms has been studied on the basis of nine different sensor parameters and four different normalization techniques. The best MLP was found to classify successfully 100% of the unknown S. aureus samples and 92% of the unknown E. coli samples, on the basis of a set of 360 training vectors and 360 test vectors taken from the lag, log and stationary growth phases. The real growth phase of the bacteria was determined from optical cell counts and was predicted from the head space samples with an accuracy of 81%. We conclude that these results show considerable promise in that the correct prediction of the type and growth phase of pathogenic bacteria may help both in the more rapid treatment of bacterial infections and in the more efficient testing of new anti-biotic drugs.

  14. Elimination and accumulation of polycyclic aromatic hydrocarbons (PAHs) in urban stormwater wet detention ponds

    DEFF Research Database (Denmark)

    Istenič, Daria; Arias, Carlos Alberto; Matamoros, Victor

    2011-01-01

    The concentrations of polycyclic aromatic hydrocarbons (PAHs) in water and sediments of seven wet detention ponds receiving urban stormwater were investigated. The ponds comprised traditional wet detention ponds with a permanent wet volume and a storage volume as well as ponds that were expanded...

  15. Assessment of nitrogen and sulphur cycle bacteria and shrimp production in ponds treated with biological products

    Institute of Scientific and Technical Information of China (English)

    Thangapalam Jawahar Abraham; Shubhadeep Ghosh; Debasis Sasmal

    2015-01-01

    Objective:To study the influence of biological products on the levels of nitrogen and sulphur cycle bacteria in shrimp culture systems of West Bengal, India. Methods: The pond water and sediment samples were analyzed for physico-chemical parameters as per standard methods. The bacteria involved in ammonification, nitrification, denitrification, sulphate reduction and sulphur oxidation were enumerated by most probable number technique. Results:The semi-intensive and modified extensive shrimp farms used a variety of biological products during various stages of production. No biological products were used in traditional farms. The water and sediment samples of modified extensive system recorded significantly higher mean heterotrophic bacterial counts. The counts of ammonia, nitrite and sulphur oxidizers, and nitrate and sulphate reducers varied among the systems. The cycling of nitrogen and sulphur appeared to be affected with the intensification of culture practices. Conclusions:The application of biological products in certain systems helped to maintain the bacteria involved in nitrogen and sulphur cycles and safe levels of ammonia, nitrite and nitrate. An assessment of these metabolically active bacteria in shrimp culture ponds and the application of right kind microbial products would help ameliorate the organic pollution in shrimp aquaculture.

  16. Geohydrology and limnology of Walden Pond, Concord, Massachusetts

    Science.gov (United States)

    Colman, John A.; Friesz, Paul J.

    2001-01-01

    The trophic ecology and ground-water contributing area of Walden Pond, in Concord and Lincoln, Mass., were investigated by the U.S. Geological Survey in cooperation with the Massachusetts Department of Environmental Management from April 1997 to July 2000. Bathymetric investigation indicated that Walden Pond (24.88 hectares), a glacial kettle-hole lake with no surface inlet or outlet, has three deep areas. The maximum depth (30.5 meters) essentially was unchanged from measurements made by Henry David Thoreau in 1846. The groundwater contributing area (621,000 square meters) to Walden Pond was determined from water-table contours in areas of stratified glacial deposits and from land-surface contours in areas of bedrock highs. Walden Pond is a flow-through lake: Walden Pond gains water from the aquifer along its eastern perimeter and loses water to the aquifer along its western perimeter. Walden Pond contributing area also includes Goose Pond and its contributing area. A water budget calculated for Walden Pond, expressed as depth of water over the lake surface, indicated that 45 percent of the inflow to the lake was from precipitation (1.215 meters per year) and 55 percent from ground water (1.47 meters per year). The groundwater inflow estimate was based on the average of two different approaches including an isotope mass-balance approach. Evaporation accounted for 26 percent of the outflow from the lake (0.71 meters per year) whereas lake-water seepage to the groundwater system contributed 74 percent of the outflow (1.97 meters per year). The water-residence time of Walden Pond is approximately 5 years. Potential point sources of nutrients to ground water, the Concord municipal landfill and a trailer park, were determined to be outside the Walden Pond groundwater contributing area. A third source, the septic leach field for the Walden Pond State Reservation facilities, was within the groundwater contributing area. Nutrient budgets for the lake indicated that

  17. Using carbon stable isotope ratio(δ13C) to evaluate contribution of artificial feeds to growth of pond cultured juvenile sea cucumber Apostichopus japonicus (Selenka)%人工饲料对刺参幼参生长贡献的碳稳定同位素法分析

    Institute of Scientific and Technical Information of China (English)

    金波昌; 董双林; 田相利; 王芳; 高勤峰; 林光辉; 管建洪

    2013-01-01

    Sea cucumber Apostichopus japonicus ( Selenka) is a typical deposit-feeder, that is, food came from some organic matter in sediment such as bacteria, prozotoa, benthic microalgae and detritus of macroalgae. Artificial feeds are applied in some areas for sea cucumber farming to increase production of the pond cultured sea cucumbers,however, to what extent the artificial feed contributes to their growth is still unclear. Study on the food sources by a traditional way of direct gut content analysis has limitations. Stable isotope is a predictable method to evaluate food sources of A. Japonicus. The present experiments were conducted to estimate contribution of artificial feed to growth of sea cucumber at five different stocking densities(5 ,10,15 ,25 and 35 ind/m2)using a stable carbon isotope ratio( δ13C) tracer. Sea cucumbers with an average weight of(4.78 ±0.58)g were randomly assigned to the enclosures. The animals were fed with artificial feed at 8:00 every day,at a feeding rate of about 5% wet weight. There were 5 treatments and 3 replicates in the experiment that lasted for 6 months. The control treatments without feed were set simultaneously. A lab experiment with four plastic aquaria(100 cm x 60 cm x 60 cm) was conducted and feeding time and ration were the same as the pond experiment. The results showed that the final weight and δ13 C value of sea cucumbers were affected markedly by both artificial feed and stocking density (P < 0. 05). With stocking density increasing,final weight of the animals decreased from(35. 62 ± 3. 50) g to(24. 59 ± 4. 38)g,and with stocking density increasing from 5 ind/m2 to 35 ind/m2 ,the δ13C values of sea cucumbers decreased from - 13. 262%. To -15. 102%c(P <0.05). Contributions of artificial feed to the growth of the sea cucumbers increased with increasing of stocking density,only 3. 78% ±2. 98% at 5 ind/m2 to 29. 48% ±3.31% at 35 ind/m2. Previous studies showed that artificial feed contributed 23. 0% - 61. 6% to the

  18. Polyculture of white shrimp, Litopenaeus vannamei and milkfish, Chanos chanos as a strategy for efficient utilization of natural food production in ponds

    Directory of Open Access Journals (Sweden)

    Bessie Joy G. Elle

    2011-12-01

    Full Text Available Both shrimps and milkfish are important aquaculture species in the Philippines. In the presentstudy, we described a modified extensive polyculture method for white shrimp, Litopenaeus vannameiand miklkfish, Chanos chanos in ponds during the wet months. This particular culture system uses two ormore species in a particular production area with the purpose of maximizing the utilization of theavailable natural food present in the system. Two 1-hectare earthen ponds were prepared and addedwith organic and/or inorganic fertilizers to enhance natural food production. The ponds were stocked withwhite shrimp postlarvae (PL at a density of 1 PL m-2 and milkfish at 750 juveniles ha-1. There was nowater exchange during the first two months of culture followed by a bi-weekly water exchange untilharvest. No artificial feeding was provided during the culture period, instead, the ponds weresupplemented with inorganic fertilizers every month to ensure stable production of natural food. Bothshrimps and milkfish appeared healthy and no disease outbreaks were observed during the productioncycle. The physico-chemical parameters of the water in the ponds were within the optimum levels thatare required for both shrimp and milkfish farming. The phytoplankton population was stable andpredominantly composed of Chlorella sp., a green microalga (Chlorophyta. The cultured stock wereharvested after 100 days of culture at sizes of 13-15 for white shrimp and > 250 g for milkfish. Therewas high survival rate of milkfish but low for white shrimps, and this could be affected by the prevailingclimatic condtions during culture and the age and size of the species during stocking.

  19. Effect of C/N ratio levels and stocking density of Labeo victorianus on pond environmental quality using maize flour as a carbon source

    NARCIS (Netherlands)

    Magondu, E.W.; Charo-Karisa, H.; Verdegem, M.C.J.

    2013-01-01

    The main obstacle in developing intensive fish culture is waste management which is detrimental to the environment. To mitigate environmental impacts associated with effluent discharge, measures should be put in place to avoid deterioration of the pond environment. The addition of carbon materials i

  20. The Big-Fish-Little-Pond Effect: Generalizability of Social Comparison Processes over Two Age Cohorts from Western, Asian, and Middle Eastern Islamic Countries

    Science.gov (United States)

    Marsh, Herbert W.; Abduljabbar, Adel Salah; Morin, Alexandre J. S.; Parker, Philip; Abdelfattah, Faisal; Nagengast, Benjamin; Abu-Hilal, Maher M.

    2015-01-01

    Extensive support for the seemingly paradoxical negative effects of school- and class-average achievement on academic self-concept (ASC)-the big-fish-little-pond effect (BFLPE)--is based largely on secondary students in Western countries or on cross-cultural Program for International Student Assessment studies. There is little research testing the…

  1. 一种新型对虾多池循环水综合养殖模式%A NEW SHRIMP POLY PONDED RECIRCULATING POLYCULTURE SYSTEM

    Institute of Scientific and Technical Information of China (English)

    黄国强; 李德尚; 董双林

    2001-01-01

    This paper gives a brief introduction of the present shrimp culture model and describes, with emphasis,the principle, features and advantages of the shrimp poly-ponded circulating polyculture model in details. The perspectives of this model are also discussed.

  2. West Knox Pond water budget and water quality

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The purpose of this report is to analyze the water budget and water quality for West Knox Pond for the May through September period of 2002 and 2003. The...

  3. Kealia Pond National Wildlife Refuge: Comprehensive Conservation Plan

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This Comprehensive Conservation Plan (CCP) was written to guide management on Kealia Pond Wildlife Refuge for the next 15 years. This plan outlines the Refuge vision...

  4. Trustom Pond National Wildlife Refuge: Comprehensive Conservation Plan

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This Comprehensive Conservation Plan (CCP) was written to guide management on Trustom Pond NWR for the next 15 years. This plan outlines the Refuge vision and...

  5. Solar-induced thermal activity and stratification in pond water

    CERN Document Server

    Brownridge, James D

    2015-01-01

    Ponds are universally used to store water for a large number of uses. With the increasing demand for more fresh water, ponds, lakes and reservoirs are likely to be constructed on a larger scale. We must understand the effects of environmental changes on fresh water if we are to most efficiently utilize this resource. This study undertakes to increase our understanding of the rate of thermal response of ponds and other bodies of water to every-day environmental changes. The central research agenda is to investigate how the temperature of pond water from top to bottom responds to the day/night cycle, changes in air temperature just above the surface, cloud conditions, and other sudden environmental changes. Data collection for this study spanned October 2007 to June 2011 and had a continuous time resolution of 50 seconds.

  6. Island ponds mitigation monitoring and reporting : Year 3 – 2008

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report presents Year 3 (2008) monitoring results for Island Ponds Restoration Project on Don Edwards San Francisco Bay NWR. The Santa Clara Valley Water...

  7. Island ponds mitigation monitoring and reporting : Year 4 – 2009

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The Santa Clara Valley Water District and the U.S. Fish and Wildlife Service Don Edwards National Wildlife Refuge implemented the Island Ponds Restoration Project to...

  8. optimum arrangement of ponds in a given area

    African Journals Online (AJOL)

    User

    1Department of Civil Engineering University of Nigeria, Nsukka, Enugu State. 2Department of Civil ... optimal land use. Efficiency, cost of inter-pond pipe connections and maintenance of ... in the work will always have the same treatment ...

  9. APPROXIMATE SOLUTION USING A PERTURBATION METHOD FOR DETENTION POND DESIGN

    Institute of Scientific and Technical Information of China (English)

    Jen-Yan CHEN; Yao-Ming HONG

    2002-01-01

    It is a common practice to use a hydrological continuity equation as the governing equation in detention pond design. Although the detention volume can be evaluated using a numerical method and computer program,they are not available for engineers to use because of the difficulty involved in the numerical evaluation or the computer program may not be ready for engineers. This study intends to provide a formula for calculating the volume of a detention pond. A nonlinear continuity equation for detention pond design is obtained by applying a triangular/trapezoidal inflow hydrograph and spillway or orifice for the outflow device. This perturbation method is employed to resolve the equation. After discussing the omission and curve fitting methods,a formula for detention pond design is proposed.Several examples are displayed and a high agreement with the numerical result is obtained.

  10. Production of premium fuels from coal refuse pond material

    Energy Technology Data Exchange (ETDEWEB)

    Honaker, R.Q.; Patil, D.P.; Sirkeci, A.; Patwardhan, A. [University of Kentucky, Lexington, KY (United States). Dept. of Mining Engineering

    2001-11-01

    Because of increasing production of fine coal during mining over the past century and because of inefficient fine-coal recovery technologies, a vast reserve of high-quality coal now exists in refuse ponds. A novel fine-coal circuit, consisting of a hindered-bed classifier, an enhanced gravity concentrator and a flotation column, was evaluated for the recovery of fine coal from refuse ponds. The treatment of a pond derived from Pittsburgh No. 8 seam coal resulted in the production of a premium fuel containing less than 5 % ash and a calorific value of about 30,170 kJ/kg with 60% mass yield. Results from the treatment of two refuse pond materials are presented.

  11. South Bay Salt Ponds Restoration Project : Final Data Acquisition Plan

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This document provides the Data Acquisition Plan for the South Bay Salt Pond Restoration Project. The purpose of the Data Acquisition Plan is to guide the collection...

  12. Western Pond Turtle Observations - Region 1 [ds313

    Data.gov (United States)

    California Department of Resources — This dataset was developed in an effort to compile Western Pond Turtle (Clemmys marmorata) observations in CDFG Region 1. Steve Burton (CDFG Staff Environmental...

  13. Pond Creek National Wildlife Refuge: Comprehensive Conservation Plan

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This Comprehensive Conservation Plan (CCP) was written to guide management on Pond Creek NWR for the next 15 years. This plan outlines the Refuge vision and purpose...

  14. EXPERIMENTAL INVESTIGATION OF SOLAR POND PERFORMANCE IN KARABUK ENVIRONMENT

    Directory of Open Access Journals (Sweden)

    Mehmet ÖZKAYMAK

    2004-01-01

    Full Text Available The solar energy, one of the alternative energy sources, can be economically and cheaply and efficiently collected with solar ponds. In this study, varying concentrations of sodium carbonate dilution in the solar pond in terms of heat storage performance has been examined. Experiment apparatus has been located Zonguldak Karaelmas University Karabük Technical Education Faculty. Five experiments with different density levels have been done and the changes in the temperature and density have been presented graphically within the solar pond. The experiments show that the temperature difference between the bottom and top level of solar pond is max. 21 °C and the highest temperature in lower convective zone (LCZ has been measured as 49 °C.

  15. Environmental Assessment : Two Ponds Wetland Preserve, Arvada, Colorado

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Environmental Assessment for the acquisition of approximately 80 acres known as Two Ponds Wetland Preserve. The Fish and Wildlife Service has responded to selected...

  16. Investigation of the environmental impacts of sedimentation in Anzali Pond

    Science.gov (United States)

    Barmal, Milad; Neshaei, Seyed Ahmad; Farzan, Niloofar

    2016-04-01

    Anzali harbor is the most essential transportation pole between Iran and other countries of the Caspian Sea basin. Anzali pond is an important ecosystem in the region due to its unique plant and animal species. In order to determine the effects of interaction between pond and sea, a series of in-depth studies and analysis on the pattern of sedimentation in Anzali harbor and pond were performed. The study area is Anzali harbor and pond which is located in southwest of the Caspian Sea in Iran. In recent years the economical importance and improvement program of this region has devoted many scientists and authorities attention to itself. In this paper, researches on environmental impact by sediment and pollution in this zone are performed. Analysis indicates that by disposal of sediment and pollution in this area, the physical and chemical quality of water has declined. Some practical suggestions are made to improve the quality of the studied region in terms of environmental aspects.

  17. Habitat Management Plan for Pond Creek National Wildlife Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The Pond Creek National Wildlife Refuge Habitat Management Plan provides a long-term vision and specific guidance on managing habitats for the resources of concern...

  18. Modeling the summertime evolution of sea-ice melt ponds

    DEFF Research Database (Denmark)

    Lüthje, Mikael; Feltham, D.L.; Taylor, P.D.;

    2006-01-01

    We present a mathematical model describing the summer melting of sea ice. We simulate the evolution of melt ponds and determine area coverage and total surface ablation. The model predictions are tested for sensitivity to the melt rate of unponded ice, enhanced melt rate beneath the melt ponds......, vertical seepage, and horizontal permeability. The model is initialized with surface topographies derived from laser altimetry corresponding to first-year sea ice and multiyear sea ice. We predict that there are large differences in the depth of melt ponds and the area of coverage between the two types...... of ice. We also find that the vertical seepage rate and the melt rate of unponded ice are important in determining the total surface ablation and area covered by melt ponds....

  19. The Trail Inventory of Kealia Pond NWR [Cycle 2

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The purpose of this report is to create a baseline inventory of all non-motorized trails on Kealia Pond National Wildlife Refuge. Trails in this inventory are...

  20. Water quality assessment of razorback sucker grow-out ponds

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Water quality parameters had never been assessed in these grow-out ponds. Historically growth, condition, and survival of razorback suckers have been variable...

  1. Modeling the summertime evolution of sea-ice melt ponds

    DEFF Research Database (Denmark)

    Lüthje, Mikael; Feltham, D.L.; Taylor, P.D.

    2006-01-01

    We present a mathematical model describing the summer melting of sea ice. We simulate the evolution of melt ponds and determine area coverage and total surface ablation. The model predictions are tested for sensitivity to the melt rate of unponded ice, enhanced melt rate beneath the melt ponds......, vertical seepage, and horizontal permeability. The model is initialized with surface topographies derived from laser altimetry corresponding to first-year sea ice and multiyear sea ice. We predict that there are large differences in the depth of melt ponds and the area of coverage between the two types...... of ice. We also find that the vertical seepage rate and the melt rate of unponded ice are important in determining the total surface ablation and area covered by melt ponds....

  2. Convergent Diversity and Trait Composition in Temporary Streams and Ponds

    Science.gov (United States)

    2016-05-19

    2002, Vieira et al. 2004, Hoeinghaus et al. 2007) influences invertebrate and vertebrate species richness and composition, predator distribution...T. 2000. Annual and seasonal variation and the effects of hydroperiod on benthic macroin- vertebrates of seasonal forest (“vernal”) ponds in central...term studies of vertebrate communities. Academic Press, San Di- ego, California, USA. Skelly, D. K. 1996. Pond drying, predators, and the distri

  3. Dissolved organic matter photolysis in Canadian arctic thaw ponds

    Science.gov (United States)

    Laurion, Isabelle; Mladenov, Natalie

    2013-09-01

    The abundant thaw lakes and ponds in the circumarctic receive a new pool of organic carbon as permafrost peat soils degrade, which can be exposed to significant irradiance that potentially increases as climate warms and ice cover shortens. Exposure to sunlight is known to accelerate the transformation of dissolved organic matter (DOM) into molecules that can be more readily used by microbes. We sampled the water from two common classes of ponds found in the ice-wedge system of continuous permafrost regions of Canada, polygonal and runnel ponds, and followed the transformation of DOM over 12 days by looking at dissolved organic carbon (DOC) concentration and DOM absorption and fluorescence properties. The results indicate a relatively fast decay of color (3.4 and 1.6% loss d-1 of absorption at 320 nm for the polygonal and runnel pond, respectively) and fluorescence (6.1 and 8.3% loss d-1 of total fluorescent components, respectively) at the pond surface, faster in the case of humic-like components, but insignificant losses of DOC over the observed period. This result indicates that direct DOM mineralization (photochemical production of CO2) is apparently minor in thaw ponds compared to the photochemical transformation of DOM into less chromophoric and likely more labile molecules with a greater potential for microbial mineralization. Therefore, DOM photolysis in arctic thaw ponds can be considered as a catalytic mechanism, accelerating the microbial turnover of mobilized organic matter from thawing permafrost and the production of greenhouse gases, especially in the most shallow ponds. Under a warming climate, this mechanism will intensify as summers lengthen.

  4. 2101-M pond closure plan. Volume 1, Revision 2

    Energy Technology Data Exchange (ETDEWEB)

    Izatt, R. D.; Lerch, R. E.

    1993-06-01

    This document describes activities for the closure of a surface impoundment (2101-M Pond) at the Hanford Site. The 2101-H Pond was initially constructed in 1953 to serve as a drainage collection area for the 2101-H Building. (Until the Basalt Waste Isolation Project (BWIP) Laboratory was constructed in the 2101-M Building in 1979--1981, the only source contributing discharge to the pond was condensate water from the 2101-H Building heating, ventilation, and air conditioning (HVAC) system. The drains for the BWIP Laboratory rooms were plumbed into a 4-in., cast-iron, low-pressure drain pipe that carries waste water from the HVAC system to the pond. During the active life of the BWIP Laboratory, solutions of dissolved barium in groundwater samples were discharged to the 2101-M Pond via the laboratory drains. As a result of the discharges, a Part A permit application was initially submitted to the Washington State Department of Ecology (Ecology) in August 1986 which designates the 2101-M Pond as a surface impoundment.

  5. Sediment remediation of the Hespeler Mill Pond, Cambridge, Ontario

    Energy Technology Data Exchange (ETDEWEB)

    Angeloni, D.; Eby, M.; Jarvis, S.; Martin, P. [Univ. of Guelph, School of Engineering, Guelph, Ontario (Canada)]. E-mail: danielle.angeloni@earthtech.ca

    2002-06-15

    'Full text:' Low dissolved oxygen levels and large accumulated sediment remediation alternatives were examined to assemble the Hespeler Mill Pond, Cambridge (HMP) into a healthier and more desirable recreational area in the City of Cambridge. The theory that a large amount of sediment has been deposited into the HMP from the Speed River upstream over a number of years predicts the depressed oxygen levels, high nutrient-loading rates and the odour problems in the summer months. The initial phase in the remediation plan for this project involved extensive background research and investigation. The focus was on determining the characteristics of the sediment and the history of the pond, to ultimately decide if the sediment was the source of the issues. Dissolved oxygen field tests and sediment sampling were conducted to get information on the magnitude of the problem and the environmental hazards potentially present in the pond. The pond was modelled utilising the Streeter-Phelps oxygen-sag model to predict the oxygen deficit. Biochemical Oxygen Demand (BOD{sub 5}) testing was completed to determine the oxygen demand in the pond. These tests were conducted by using water samples obtained from various sample points at the pond. The proposed solution is a combined dredging and aeration approach. Mechanical dredging using a clamshell bucket and the installation of aerators is expected to solve the dissolved oxygen and water quality issues. (author)

  6. Modeling a ponded infiltration experiment at Yucca Mountain, NV

    Energy Technology Data Exchange (ETDEWEB)

    Hudson, D.B.; Guertal, W.R. [Foothill Engineering, Inc., Mercury, NV (United States); Flint, A.L. [Geological Survey, Mercury, NV (United States)

    1994-12-31

    Yucca Mountain, Nevada is being evaluated as a potential site for a geologic repository for high level radioactive waste. As part of the site characterization activities at Yucca Mountain, a field-scale ponded infiltration experiment was done to help characterize the hydraulic and infiltration properties of a layered dessert alluvium deposit. Calcium carbonate accumulation and cementation, heterogeneous layered profiles, high evapotranspiration, low precipitation, and rocky soil make the surface difficult to characterize.The effects of the strong morphological horizonation on the infiltration processes, the suitability of measured hydraulic properties, and the usefulness of ponded infiltration experiments in site characterization work were of interest. One-dimensional and two-dimensional radial flow numerical models were used to help interpret the results of the ponding experiment. The objective of this study was to evaluate the results of a ponded infiltration experiment done around borehole UE25 UZN {number_sign}85 (N85) at Yucca Mountain, NV. The effects of morphological horizons on the infiltration processes, lateral flow, and measured soil hydaulic properties were studied. The evaluation was done by numerically modeling the results of a field ponded infiltration experiment. A comparison the experimental results and the modeled results was used to qualitatively indicate the degree to which infiltration processes and the hydaulic properties are understood. Results of the field characterization, soil characterization, borehole geophysics, and the ponding experiment are presented in a companion paper.

  7. Quality control summary report for the RFI/RI assessment of the submerged sediment core samples taken at Par Pond, Pond C, and L-Lake

    Energy Technology Data Exchange (ETDEWEB)

    Koch, J. II

    1996-12-01

    This report presents a summary of the sediment characterization performed under the direction of the Westinghouse Savannah River Company`s (WSRC) Environmental Protection Department/Environmental Monitoring Section (EPD/EMS) in support of Par Pond, Pond C, and L- Lake. This characterization will be a screening study and will enable the Environmental Sciences Section (ESS) to develop a defensible contaminants of concern list for more extensive characterization of the Par Pond, Pond C, and L-Lake.

  8. Field Study Plant/Invertebrate Associations Found In Pond-C and Pond-D of Erie Wildlife Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The overall purpose of this study is to determine the extent of protienasious material, invertebrate life, present in the ponds listed and to make any possible...

  9. Comparison of the Cytotoxic Potential of Cigarette Smoke and Electronic Cigarette Vapour Extract on Cultured Myocardial Cells

    Directory of Open Access Journals (Sweden)

    Dimitris Tsiapras

    2013-10-01

    Full Text Available Background: Electronic cigarettes (ECs have been marketed as an alternative-to-smoking habit. Besides chemical studies of the content of EC liquids or vapour, little research has been conducted on their in vitro effects. Smoking is an important risk factor for cardiovascular disease and cigarette smoke (CS has well-established cytotoxic effects on myocardial cells. The purpose of this study was to evaluate the cytotoxic potential of the vapour of 20 EC liquid samples and a “base” liquid sample (50% glycerol and 50% propylene glycol, with no nicotine or flavourings on cultured myocardial cells. Included were 4 samples produced by using cured tobacco leaves in order to extract the tobacco flavour. Methods: Cytotoxicity was tested according to the ISO 10993-5 standard. By activating an EC device at 3.7 volts (6.2 watts—all samples, including the “base” liquid and at 4.5 volts (9.2 watts—four randomly selected samples, 200 mg of liquid evaporated and was extracted in 20 mL of culture medium. Cigarette smoke (CS extract from three tobacco cigarettes was produced according to ISO 3308 method (2 s puffs of 35 mL volume, one puff every 60 s. The extracts, undiluted (100% and in four dilutions (50%, 25%, 12.5%, and 6.25%, were applied to myocardial cells (H9c2; percent-viability was measured after 24 h incubation. According to ISO 10993-5, viability of 6.25% (viability: 76.9 ± 2.0% at 6.25%, 38.2 ± 0.5% at 12.5%, 3.1 ± 0.2% at 25%, 5.2 ± 0.8% at 50%, and 3.9 ± 0.2% at 100% extract concentration. Three EC extracts (produced by tobacco leaves were cytotoxic at 100% and 50% extract concentrations (viability range: 2.2%–39.1% and 7.4%–66.9% respectively and one (“Cinnamon-Cookies” flavour was cytotoxic at 100% concentration only (viability: 64.8 ± 2.5%. Inhibitory concentration 50 was >3 times lower in CS extract compared to the worst-performing EC vapour extract. For EC extracts produced by high-voltage and energy, viability was

  10. [Bacteria ecology in planting-culturing system].

    Science.gov (United States)

    Huang, Fenglian; Xia, Beicheng; Dai, Xin; Chen, Guizhu

    2004-06-01

    Planting-culturing system in inter-tidal zone is a new type eco-culturing model. The survey on bacteria biomass and water quality in the designed planting-culturing system in inter-tidal zone showed that the mangrove planted in the system improved water quality and made water quality to II-III type, better than the IV and V type in the control pond. Designed ponds made heterotrophic bacteria, vibrio, phosphorus bacteria and enzyme-producing bacteria populations 1-2 order lower than the control pond without mongrove planting. Correlation analyses with CORREL software showed that the biomass of these bacteria was positively related with the nitrogen and phosphorus contents in water of the system, and the correlation coefficient for heterogeneous bacteria and vibrio was up to 0.9205. Heterotrophic bacteria and vibrio could be used as the water-quality monitoring organisms.

  11. High rates of methane emissions from south taiga wetland ponds.

    Science.gov (United States)

    Glagolev, M.; Kleptsova, I.; Maksyutov, S.

    2012-04-01

    Since wetland ponds are often assumed to be insignificant sources of methane, there is a limited data about its fluxes. In this study, we found surprisingly high rates of methane emission at several shallow ponds in the south taiga zone of West Siberia. Wetland ponds within the Great Vasyugan Mire ridge-hollow-pool patterned bog system were investigated. 22 and 24 flux measurements from ponds and surrounded mires, respectively, were simultaneously made by a static chamber method in July, 2011. In contrast to previous measurements, fluxes were measured using the small boat with floated chamber to avoid disturbance to the water volume. Since the ebullition is most important emission pathway, minimization of physical disturbance provoking gas bubbling significantly increases the data accuracy. Air temperature varied from 15 to 22° C during the measurements, and pH at different pond depths - from 4.4 to 5. As it was found, background emission from surrounding ridges and hollows was 1.7/2.6/3.3 mgC·m-2·h1 (1st/2nd/3rd quartiles). These rates are in a perfect correspondence with the typical methane emission fluxes from other south taiga bogs. Methane emission from wetland ponds turned out to be by order of magnitude higher (9.3/11.3/15.6 mgC·m-2·h1). Comparing to other measurements in West Siberia, many times higher emissions (70.9/111.6/152.3 mgC·m-2·h1) were found in forest-steppe and subtaiga fen ponds. On the contrary, West Siberian tundra lakes emit methane insignificantly, with the flux rate close to surrounding wetlands (about 0.2-0.3 mgC·m-2·h1). Apparently, there is a naturally determined distribution of ponds with different flux rates over different West Siberia climate-vegetation zones. Further investigations aiming at revelation of the zones with different fluxes would be helpful for total flux revision purposes. With respect to other studies, high emission rates were already detected, for instance, in Baltic ponds (Dzyuban, 2002) and U.K. lakes

  12. Biomass production of multipopulation microalgae in open air pond for biofuel potential.

    Science.gov (United States)

    Selvakumar, P; Umadevi, K

    2016-04-01

    Biodiesel gains attention as it is made from renewable resources and has considerable environmental benefits. The present investigation has focused on large scale cultivation of multipopulation microalgae in open air pond using natural sea water without any additional nutritive supplements for low cost biomass production as a possible source of biofuel in large scale. Open air algal pond attained average chlorophyll concentration of 11.01 µg/L with the maximum of 43.65 µg/L as well as a higher lipid concentration of 18% (w/w) with lipid content 9.3 mg/L on the 10th day of the culture; and maximum biomass of 0.36 g/L on the 7th day of the culture. Composition analysis of fatty acid methyl ester (FAME) was performed by gas chromatography and mass spectrometry (GCMS). Multipopulation of algal biomass had 18% of total lipid content with 55% of total saturated fatty acids (SFA), 35.3% of monounsaturated fatty acids (MUFA) and 9.7% of polyunsaturated fatty acids (PUFA), revealing a potential source of biofuel production at low cost.

  13. Deep Subsurface Life from North Pond: Enrichment, Isolation, Characterization and Genomes of Heterotrophic Bacteria.

    Science.gov (United States)

    Russell, Joseph A; León-Zayas, Rosa; Wrighton, Kelly; Biddle, Jennifer F

    2016-01-01

    Studies of subsurface microorganisms have yielded few environmentally relevant isolates for laboratory studies. In order to address this lack of cultivated microorganisms, we initiated several enrichments on sediment and underlying basalt samples from North Pond, a sediment basin ringed by basalt outcrops underlying an oligotrophic water-column west of the Mid-Atlantic Ridge at 22°N. In contrast to anoxic enrichments, growth was observed in aerobic, heterotrophic enrichments from sediment of IODP Hole U1382B at 4 and 68 m below seafloor (mbsf). These sediment depths, respectively, correspond to the fringes of oxygen penetration from overlying seawater in the top of the sediment column and upward migration of oxygen from oxic seawater from the basalt aquifer below the sediment. Here we report the enrichment, isolation, initial characterization and genomes of three isolated aerobic heterotrophs from North Pond sediments; an Arthrobacter species from 4 mbsf, and Paracoccus and Pseudomonas species from 68 mbsf. These cultivated bacteria are represented in the amplicon 16S rRNA gene libraries created from whole sediments, albeit at low (up to 2%) relative abundance. We provide genomic evidence from our isolates demonstrating that the Arthrobacter and Pseudomonas isolates have the potential to respire nitrate and oxygen, though dissimilatory nitrate reduction could not be confirmed in laboratory cultures. The cultures from this study represent members of abundant phyla, as determined by amplicon sequencing of environmental DNA extracts, and allow for further studies into geochemical factors impacting life in the deep subsurface.

  14. Biodiesel production potential of wastewater treatment high rate algal pond biomass.

    Science.gov (United States)

    Mehrabadi, Abbas; Craggs, Rupert; Farid, Mohammed M

    2016-12-01

    This study investigates the year-round production potential and quality of biodiesel from wastewater treatment high rate algal pond (WWT HRAP) biomass and how it is affected by CO2 addition to the culture. The mean monthly pond biomass and lipid productivities varied between 2.0±0.3 and 11.1±2.5gVSS/m(2)/d, and between 0.5±0.1 and 2.6±1.1g/m(2)/d, respectively. The biomass fatty acid methyl esters were highly complex which led to produce low-quality biodiesel so that it cannot be used directly as a transportation fuel. Overall, 0.9±0.1g/m(2)/d (3.2±0.5ton/ha/year) low-quality biodiesel could be produced from WWT HRAP biomass which could be further increased to 1.1±0.1g/m(2)/d (4.0ton/ha/year) by lowering culture pH to 6-7 during warm summer months. CO2 addition, had little effect on both the biomass lipid content and profile and consequently did not change the quality of biodiesel.

  15. Metal concentrations in water, sediment, and fish from sewage-fed aquaculture ponds of Kolkata, India.

    Science.gov (United States)

    Adhikari, S; Ghosh, L; Rai, S P; Ayyappan, S

    2009-12-01

    The concentrations of lead, cadmium, chromium, copper, and zinc were investigated in the sewage-fed pond water, sediment, and the various organs of Labeo rohita, Catla catla, Cirrhinus mrigala, Oreochromis mossambicus, and Cyprinus carpio cultured in sewage-fed ponds, Kolkata, India. Among the metals, cadmium, lead, and zinc were detected in water and, except lead, were below the water quality guideline levels for the protection of freshwater aquatic life proposed by CEQG (Canadian Environmental Quality Guidelines) and AENV (Alberta Environment). Therefore, lead could pose danger to aquatic organisms. All the five metals were detected in the sediment and, except cadmium and lead, were below the sediment quality guideline levels for aquatic life proposed by EPA (Environmental Protection Agency). Therefore, these two metals could be toxic to aquatic organisms. Significant (P > 0.05) differences were observed among the five fish species for all these metals accumulation. Also, significant (P > 0.05) differences were noticed among these metals accumulation in fish organs. Cadmium showed the least bioaccumulation, while zinc showed the highest bioaccumulation in all the fish species. Though the metal concentration in the different fish tissues was variable, the highest concentration was found in kidney and the lowest in the muscle. Concentrations of these metals in the muscle tissue of all the fish species were well below the consumption safety tolerance in fish set by WHO/FAO, and thus, so far as these metals are concerned, these sewage-fed cultured fishes are safe and suitable for human consumption.

  16. Comparison of maturation ponds and constructed wetlands as the final stage of an advanced pond system.

    Science.gov (United States)

    Tanner, C C; Craggs, R J; Sukias, J P S; Park, J B K

    2005-01-01

    The treatment performance of a maturation pond (MP), the typical final polishing stage of an Advanced Pond System (APS), is compared with that of a surface-flow constructed wetland (CW) over 19 months. Both received approximately 67 mm d-1 of wastewater after passage through upstream stages of the APS. The MP, with greater sunlight exposure, had higher algal biomass (and associated suspended solids) than the CW, showed higher dissolved oxygen (DO) concentrations and greater diurnal variation in DO and pH. Neither polishing stages reduced nutrients markedly, with the CW exporting slightly more NH(3)-N and DRP, and less NO(3)-N than the MP. Disinfection was more efficient in the MP (geometric mean 1 log load removal, 12 MPN (100ml)-1) compared to the CW (0.47 log load removal, 53 MPN (100ml)-1). Incorporation of a final rock filter (28% of area) reduced median solids levels to wetland vegetation (promoting sedimentation and denitrification, and providing refugia for zooplankton) may provide more consistent effluent quality that either stage alone.

  17. Individual variation affects departure rate from the natal pond in an ephemeral pond-breeding anuran

    Science.gov (United States)

    Chelgren, N.D.; Rosenberg, D.K.; Heppell, S.S.; Gitelman, A.I.

    2008-01-01

    Frogs exhibit extreme plasticity and individual variation in growth and behavior during metamorphosis, driven by interactions of intrinsic state factors and extrinsic environmental factors. In northern red-legged frogs (Rana aurora Baird and Girard, 1852), we studied the timing of departure from the natal pond as it relates to date and size of individuals at metamorphosis in the context of environmental uncertainty. To affect body size at metamorphosis, we manipulated food availability during the larval stage for a sample (317) of 1045 uniquely marked individuals and released them at their natal ponds as newly metamorphosed frogs. We recaptured 34% of marked frogs in pitfall traps as they departed and related the timing of their initial terrestrial movements to individual properties using a time-to-event model. Median age at first capture was 4 and 9 days postmetamorphosis at two sites. The rate of departure was positively related to body size and to date of metamorphosis. Departure rate was strongly negatively related to time elapsed since rainfall, and this effect was diminished for smaller and later metamorphosing frogs. Individual variation in metamorphic traits thus affects individuals' responses to environmental variability, supporting a behavioral link with variation in survival associated with these same metamorphic traits. ?? 2008 NRC.

  18. National and Cultural Differences in the C2C Electronic Marketplace: An Investigation into Transactional Behaviors of Chinese, American, and French Consumers on eBay

    Institute of Scientific and Technical Information of China (English)

    ZHU Yan; LI Yan; Mathieu Leboulanger

    2009-01-01

    With the Internet connecting every part of the wodd, electronic marketplaces provide a world-wide transaction platform for global businesses. However, consumers from different countries demonstrate distinct purchasing behaviors online. This study uses eBay as the consumer-to-consumer electronic marketplace to investigate the eBay mechanisms and purchasing habits of consumers from the United States, France, and China to evaluate the effects of cultural and national differences on purchasing habits. This study uses data on national transactions and reputation profiles of sellers gathered from eBay.com, eBay.fr, and eBay.com.cn, including both cross-sectional data and panel data to provide a comprehensive comparison of cultural be-havior in the trading process as well as the influence of eBay's reputation management system on online pricing in these three countries. Significant differences confirm that purchasing behavior differs in various national consumer-to-consumer electronic marketplaces and the importance of cultural behavioral patterns.

  19. Light and electron microscopic localization of GABAA-receptors on cultured cerebellar granule cells and astrocytes using immunohistochemical techniques

    DEFF Research Database (Denmark)

    Hansen, G H; Hösli, E; Belhage, B;

    1991-01-01

    GABAA-receptors were localized in explant cultures of rat cerebellum and in dissociated primary cultures of rat cerebellar granule cells and rat cerebellar astrocytes using the monoclonal antibody bd-17 directed against the beta-subunit of the GABAA/benzodiazepine/chloride channel complex. At the...

  20. The Coliform Bacteria in the Wastewater Ponds of Doha City, Qatar

    OpenAIRE

    al Thani, Roda F. [روضة فهد آل ثاني

    2003-01-01

    The microbiological study of the wastewater and its sediment around Abu-Hamour pond (untreated wastewater pond) and Abu-NakhIa pond (treated wastewater pond), located on the outskirts of Doha City, revealed that coliform bacteria were prominently present in the former than in the latter one. E.coli. Was present in the coastal wastewater in all sites around both ponds. Yet, E. coli. was present in wet soils around theses ponds primarily near the discharge sites where new water is constantly po...

  1. Influences of radiation on carp from farm ponds in Fukushima.

    Science.gov (United States)

    Suzuki, Yuzuru

    2015-12-01

    A massive release of artificial radionuclides from the Fukushima Dai-ichi Nuclear Power Plant caused radioactive contamination of farms as well as of aquatic products. Carp in small ponds in the highly radiocontaminated area of Iitate Village, Fukushima Prefecture, have been confined to the ponds since the accident, and it is thought that the carp may have suffered health issues as a result. Therefore, I investigated the health condition of the carp in order to elucidate the effects of radiation.Blood neutrophil, monocyte and lymphocyte counts in the carp from three ponds in Fukushima were lower than those in carp from a non-polluted pond in Tochigi Prefecture. Histological observations indicated abnormal hyperplasia of macrophages in the spleen, kidney, liver and pancreas of carp in Fukushima. Although there are likely to have been deleterious effects on carp health due to the radiation in Fukushima, this has not yet been confirmed because only one control pond was available for comparison, and I was not able to find any symptoms in the carp that correlated with internal cesium concentration. Further research is now being conducted to investigate the effects of radiation on carp.

  2. Influences of radiation on carp from farm ponds in Fukushima

    Science.gov (United States)

    Suzuki, Yuzuru

    2015-01-01

    A massive release of artificial radionuclides from the Fukushima Dai-ichi Nuclear Power Plant caused radioactive contamination of farms as well as of aquatic products. Carp in small ponds in the highly radiocontaminated area of Iitate Village, Fukushima Prefecture, have been confined to the ponds since the accident, and it is thought that the carp may have suffered health issues as a result. Therefore, I investigated the health condition of the carp in order to elucidate the effects of radiation. Blood neutrophil, monocyte and lymphocyte counts in the carp from three ponds in Fukushima were lower than those in carp from a non-polluted pond in Tochigi Prefecture. Histological observations indicated abnormal hyperplasia of macrophages in the spleen, kidney, liver and pancreas of carp in Fukushima. Although there are likely to have been deleterious effects on carp health due to the radiation in Fukushima, this has not yet been confirmed because only one control pond was available for comparison, and I was not able to find any symptoms in the carp that correlated with internal cesium concentration. Further research is now being conducted to investigate the effects of radiation on carp. PMID:26666689

  3. The Influence of Micropore Oxygen Aeration on the Pond Water Quality Environment

    Directory of Open Access Journals (Sweden)

    Xiao-Jiang Chen

    2013-11-01

    Full Text Available In order to know the effects of micropore oxygen aeration on the water quality and economic output, take each 3 of micropore oxygen aeration (experimental pond and impeller oxygenation (control pond to make the comparison, indexs of two different aeration methods water were detected from May, 2012 to October, 2012. Such as water temperature, dissolved oxygen, ammonia nitrogen and nitrite, phytoplankton, chemical oxygen demand (CODMn. Results showed that, (1 the indexes of the dissolved oxygen, ammonia nitrogen, chemical oxygen demand(CODMn and nitrite of the experimental pond are all superior to that of the control pond, of which the concentration of the dissolved oxygen of the experimental pond is 8.37 mg/L which is higher than that of the control pond (5.7 mg/L. And, (CODMn in the experimental pond is 7.54 mg/L, lower than that in the control pond (10.19 mg/L. The difference between the control pond and the experimental pond was statistically significant (p<0.01. The ammonia nitrogen of the experimental pond is 0.1 mg/L, obviously lower than the control pond (0.16 mg/L. Besides, the nitrite is 0.13 mg/L in the experimental pond, lower than that of the control pond (0.21 mg/L. (2 Compared with the control pond, the experimental pond has quite higher general abundance of algae, with about 5.69×108 ind/L. Yet, there is no obvious difference between them. (3 Compared to the impeller oxygenation, the micropore oxygen aeration technology can be better to increase the dissolved oxygen in the aquaculture pond and improve the water quality. However, there is no significant influence to the phytoplankton abundance and diversity.

  4. Lime application methods, water and bottom soil acidity in fresh water fish ponds

    Directory of Open Access Journals (Sweden)

    Queiroz Julio Ferraz de

    2004-01-01

    Full Text Available Although some methods for determining lime requirement of pond soils are available and commonly used, there is still no consensus on whether it is more effective to apply liming materials to the bottoms of empty ponds or to wait and apply them over the water surface after ponds are filled. There is also little information on how deep lime reacts in pond sediment over time, and whether the depth of reaction is different when liming materials are applied to the water or to the soil. Therefore, three techniques for treating fish ponds with agricultural limestone were evaluated in ponds with clayey soils at a commercial fish farm. Amounts of agricultural limestone equal to the lime requirement of bottom soils were applied to each of three ponds by: direct application over the pond water surface; spread uniformly over the bottom of the empty pond; spread uniformly over the bottom of the empty pond followed by tilling of the bottom. Effectiveness of agricultural limestone applications did not differ among treatment methods. Agricultural limestone also reacted quickly to increase total alkalinity and total hardness of pond water to acceptable concentrations within 2 weeks after application. The reaction of lime to increase soil pH was essentially complete after one to two months, and lime had no effect below a soil depth of 8 cm. Tilling of pond bottoms to incorporate liming materials is unnecessary, and tilling consumes time and is an expensive practice; filled ponds can be limed effectively.

  5. Effects of hydrology on zooplankton communities in high-mountain ponds, Mount Rainier National Park, USA

    Science.gov (United States)

    Girdner, Scott; Larson, Gary L.

    1995-01-01

    Ten high-mountain ponds in Mount Rainier National Park, Washington State, were studied from ice-out in June through September1992 to investigate the influences of fluctuating pond volumes on zooplankton communities. All of the ponds were at maximum volume immediately after ice-out. The temporary pond with the shortest wet phase was inhabited by rotifer taxa with short generation times and a crustacean taxon with the ability to encyst as drought-resistant resting bodies at immature stages of development. Dominant zooplankton taxa in three other temporary ponds and six permanent ponds were similar. Rotifer densities typically were lower in temporary ponds relative to those in permanent ponds, although Brachionus urceolaris was abundant shortly before the temporary ponds dried. Large volume loss was associated with large declines in total abundances of crustacean populations. Daphnia rosea was not present in temporary ponds following fall recharge. In deep-permanent ponds, copepods had slower developmental rates, smaller temporal changes in total abundances of crustacean populations and two additional large-bodied crustacean taxa were present relative to the characteristics of crustacean communities in shallow-permanent ponds. Owing to their small sizes and sensitivity to environmental change, collectively ponds such as these may provide an early signal of long-term climate change in aquatic systems.

  6. Garden ponds as potential introduction pathway of ornamental crayfish

    Directory of Open Access Journals (Sweden)

    Patoka J.

    2014-01-01

    Full Text Available The private stocking of ornamental crayfish in garden ponds was discussed in previous studies, but there is a lack of detailed analysis for better understanding of this introduction pathway. The Czech Republic is one of leading EU countries in trade with ornamental crayfish and private garden ponds are popular among people. The crayfish keepers in the country were interviewed by self-administered questionnaire to gather data about principal characteristics of the keepers and detailed information about crayfish breeding that are of interest for conservation managers. Besides of releasing crayfish into garden ponds, alarming illegal behavior such as releasing of juvenile crayfish into the wild, and capturing of indigenous crayfish from wild populations, were registered. Therefore focusing on public education to increase awareness of possible unwanted consequences of crayfish release and introduction of an obligation to inform customers about hazardousness of non-indigenous crayfish species for retailers and wholesalers is recommended.

  7. Production and Cycling of Methylmercury in High Arctic Wetland Ponds

    Science.gov (United States)

    Lehnherr, I.; St. Louis, V. L.

    2010-12-01

    Some species of freshwater fish in the Canadian high Arctic contain levels of methylmercury (MeHg) that pose health risks to the northern Inuit peoples that harvest these species as a traditional food source. In temperate regions, wetlands are known natural sites of MeHg production and hence significant MeHg sources to downstream ecosystems. However, the importance of wetlands to Hg methylation in the Arctic is unclear and the sources of MeHg to arctic freshwater ecosystems are still largely unidentified. Our research is demonstrating that some shallow and warm wetland ponds on the Arctic landscape contain high MeHg concentrations compared to nearby deep and cold lakes. We used a mass-balance approach to measure the net in-pond production of MeHg in two warm wetland ponds (Ponds 1 and 2) near Lake Hazen, Ellesmere Island, Nunavut (81° N latitude). We quantified external inputs and outputs of MeHg to and from the ponds, as well as the accumulation of MeHg in the water column during the summers of 2005 and 2008. Any changes in water column MeHg concentrations that could not be accounted for by external inputs or sinks were attributed to in-pond production. The principal external input and sink of MeHg was, respectively, wet atmospheric deposition and water-column MeHg photodemethylation. For 2005, we estimate that the net flux of MeHg from sediments into the water column was 0.015 μg m-2 d-1 in Pond 1 and 0.0016 μg m-2 d-1 in Pond 2. Compared to sediment-water MeHg fluxes measured in Alaskan tundra lakes (0.0015-0.0045 μg m-2 d-1), Pond 1 sediments are a greater source of MeHg while Pond 2 is similar to the Alaskan lakes. Furthermore, the accumulation of MeHg in the water column of Pond 1 (0.0061 μg m-2 d-1) was similar to the net yield of MeHg from temperate boreal wetlands (0.0005-0.006 μg m-2 d-1), demonstrating that these Arctic wetlands are important sites of MeHg production. In addition, we used mercury stable-isotope tracers to quantify methylation and

  8. Groundwater and contaminant transport modelling at the Sydney Tar Ponds

    Energy Technology Data Exchange (ETDEWEB)

    King, M. [Groundwater Insight Inc., Halifax, NS (Canada); Check, G. [Jacques Whitford Environment Ltd., Halifax, NS (Canada); Carey, G. [Environmental Inst. for Continuing Education, Waterloo, ON (Canada); Abbey, D. [Waterloo Hydrogeologic, Waterloo, ON (Canada); Baechler, F. [ADI Ltd., Sydney, NS (Canada)

    2003-07-01

    The Muggah Creek Watershed, a tidal estuary located in Sydney, Nova Scotia, is known locally as the Tar Ponds. Over the past century, the Tar Ponds have accumulated contaminants in the contributing watershed from the iron, steel and coke manufacturing. There are sediments contaminated with polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs). A groundwater modelling program was developed to estimate current contaminant fluxes to the estuary and site streams, through groundwater. Attempts were made to incorporate a complex stratigraphic profile, where groundwater flow and contaminant transport is strongly controlled by shallow fractured bedrock, into the conceptual model developed for the site. This conceptual model for groundwater flow and contaminant transport at the Sydney Tar Ponds site was presented. The complex flow patterns between bedrock and overburden, and between the bedrock units and surface water bodies were illustrated with model simulations. It was found that groundwater flow was dominated by discharge to the streams and the estuary. 6 refs., 2 tabs., 11 figs.

  9. Cdio as the educational and cultural structuring element in the dtu b.eng. in electronics programme

    DEFF Research Database (Denmark)

    Kjærgaard, Claus; Brauer, Peter; Andersen, Jens Christian

    2011-01-01

    as a part of the complex CDIO based education. The case used is the B.Eng. study in Electronics at the Technical University of Denmark (DTU) Implementing CDIO calls for many changes in the way that we build and document an program, having implemented CDIO at the B.Eng. program in electronics, it has been...

  10. Carbon dynamics in highly heterotrophic subarctic thaw ponds

    Directory of Open Access Journals (Sweden)

    T. Roiha

    2015-07-01

    Full Text Available Global warming has accelerated the formation of permafrost thaw ponds in several subarctic and arctic regions. These ponds are net heterotrophic as evidenced by their greenhouse gas (GHG supersaturation levels (CO2 and CH4, and generally receive large terrestrial carbon inputs from the thawing and eroding permafrost. We measured seasonal and vertical variations in the concentration and type of dissolved organic matter (DOM in five subarctic thaw (thermokarst ponds in northern Quebec, and explored how environmental gradients influenced heterotrophic and phototrophic biomass and productivity. Late winter DOM had low aromaticity indicating reduced inputs of terrestrial carbon, while the high concentration of dissolved organic carbon (DOC suggests that some production of non-chromophoric dissolved compounds by the microbial food web took place under the ice cover. Summer DOM had a strong terrestrial signature, but was also characterized with significant inputs of algal-derived carbon, especially at the pond surface. During late winter, bacterial production was low (maximum of 0.8 mg C m−3 d−1 and was largely based on free-living bacterioplankton (58 %. Bacterial production in summer was high (up to 58 mg C m−3 d−1, dominated by particle-attached bacteria (67 %, and strongly correlated to the amount of terrestrial carbon. Primary production was restricted to summer surface waters due to strong light limitation deeper in the water column or in winter. The phototrophic biomass was equal to the heterotrophic biomass, but as the algae were mostly composed of mixotrophic species, most probably they used bacteria rather than solar energy in such shaded ponds. According to the δ13C analyses, non-algal carbon supported 51 % of winter and 37 % of summer biomass of the phantom midge larvae, Chaoborus sp., that are at the top of the trophic chain. Our results point to a strong heterotrophic energy pathway in these thaw pond ecosystems, where

  11. Carbon dynamics in highly heterotrophic subarctic thaw ponds

    Science.gov (United States)

    Roiha, T.; Laurion, I.; Rautio, M.

    2015-12-01

    Global warming has accelerated the formation of permafrost thaw ponds in several subarctic and arctic regions. These ponds are net heterotrophic as evidenced by their greenhouse gas (GHG) supersaturation levels (CO2 and CH4), and generally receive large terrestrial carbon inputs from the thawing and eroding permafrost. We measured seasonal and vertical variations in the concentration and type of dissolved organic matter (DOM) in five subarctic thaw (thermokarst) ponds in northern Quebec, and explored how environmental gradients influenced heterotrophic and phototrophic biomass and productivity. Late winter DOM had low aromaticity indicating reduced inputs of terrestrial carbon, while the high concentration of dissolved organic carbon (DOC) suggests that some production of non-chromophoric dissolved compounds by the microbial food web took place under the ice cover. Summer DOM had a strong terrestrial signature, but was also characterized with significant inputs of algal-derived carbon, especially at the pond surface. During late winter, bacterial production was low (maximum of 0.8 mg C m-3 d-1) and was largely based on free-living bacterioplankton (58 %). Bacterial production in summer was high (up to 58 mg C m-3 d-1), dominated by particle-attached bacteria (67 %), and strongly correlated with the amount of terrestrial carbon. Primary production was restricted to summer surface waters due to strong light limitation deeper in the water column or in winter. The phototrophic biomass was equal to the heterotrophic biomass, but as the algae were mostly composed of mixotrophic species, most probably they used bacteria rather than solar energy in such shaded ponds. Our results point to a strong heterotrophic energy pathway in these thaw pond ecosystems, where bacterioplankton dominates the production of new carbon biomass in both summer and winter.

  12. Geothermal aquaculture: a guide to freshwater prawn culture

    Energy Technology Data Exchange (ETDEWEB)

    Hayes, A.; Johnson, W.C.

    1980-05-01

    Biological data of the Malaysian prawn, Macrobrachium rosenbergii, are summarized. A history on its rearing techniques is given, but through the use of geothermal water or industrial warm water effluent, its range can be expanded. The use of wasted geothermal water at the Oregon Institute of Technology for prawn ponds is noted. Pond management and design; the hatchery design and function for larval culture; and geothermal applications (legal aspects and constraints) are discussed. (MCW)

  13. Characterising legacy spent nuclear fuel pond materials using microfocus X-ray absorption spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Bower, W.R. [Research Centre for Radwaste Disposal, School of Earth and Environmental Sciences, The University of Manchester, Oxford Road, Manchester M13 9PL (United Kingdom); National Nuclear Laboratory, Chadwick House, Warrington Road, Birchwood Park, Warrington, WA3 6AE (United Kingdom); Centre for Radiochemistry Research, Chemistry Building, The University of Manchester, Brunswick Street, Manchester M13 9PL (United Kingdom); Morris, K. [Research Centre for Radwaste Disposal, School of Earth and Environmental Sciences, The University of Manchester, Oxford Road, Manchester M13 9PL (United Kingdom); Mosselmans, J.F.W. [Diamond Light Source, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0DE (United Kingdom); Thompson, O.R. [National Nuclear Laboratory, Chadwick House, Warrington Road, Birchwood Park, Warrington, WA3 6AE (United Kingdom); Banford, A.W. [National Nuclear Laboratory, Chadwick House, Warrington Road, Birchwood Park, Warrington, WA3 6AE (United Kingdom); School of Chemical Engineering and Analytical Science, The University of Manchester, Oxford Road, Manchester, M13 9PL (United Kingdom); Law, K. [Centre for Radiochemistry Research, Chemistry Building, The University of Manchester, Brunswick Street, Manchester M13 9PL (United Kingdom); Pattrick, R.A.D., E-mail: richard.pattrick@manchester.ac.uk [Research Centre for Radwaste Disposal, School of Earth and Environmental Sciences, The University of Manchester, Oxford Road, Manchester M13 9PL (United Kingdom)

    2016-11-05

    Highlights: • A sample from a spent fuel pond wall has been analysed via X-ray spectroscopy. • Autoradiography shows a patchy distribution of radioactivity on the core face. • μXAS across a ‘hot spot’ showed Sr associates with the TiO{sub 2} pigment in the paint. • Original concrete coatings prove effective at limiting radionuclide migration. • Sorption studies show Sr immobilisation by the concrete and Cs by aggregate clasts. - Abstract: Analysis of a radioactive, coated concrete core from the decommissioned, spent nuclear fuel cooling pond at the Hunterston-A nuclear site (UK) has provided a unique opportunity to study radionuclides within a real-world system. The core, obtained from a dividing wall and sampled at the fill level of the pond, exhibited radioactivity (dominantly {sup 137}Cs and {sup 90}Sr) heterogeneously distributed across both painted faces. Chemical analysis of the core was undertaken using microfocus spectroscopy at Diamond Light Source, UK. Mapping of Sr across the surface coatings using microfocus X-ray fluorescence (μXRF) combined with X-ray absorption spectroscopy showed that Sr was bound to TiO{sub 2} particles in the paint layers, suggesting an association between TiO{sub 2} and radiostrontium. Stable Sr and Cs sorption experiments using concrete coupons were also undertaken to assess their interactions with the bulk concrete in case of a breach in the coating layers. μXRF and scanning electron microscopy showed that Sr was immobilized by the cement phases, whilst at the elevated experimental concentrations, Cs was associated with clay minerals in the aggregates. This study provides a crucial insight into poorly understood infrastructural contamination in complex systems and is directly applicable to the UK’s nuclear decommissioning efforts.

  14. Biodeposition, respiration, and excretion rates of an introduced clam Mercenaria mercenaria in ponds with implications for potential competition with the native clam Meretrix meretrix in Shuangtaizi estuary, China

    Science.gov (United States)

    Zhang, Anguo; Yuan, Xiutang; Hou, Wenjiu; Li, Xiaodong; Zhao, Kai; Chen, Weixin; Su, Xiurong

    2016-05-01

    This study aimed to evaluate the potential impacts of an introduced clam Mercenaria mercenaria on estuarine ecosystem, and implications for the niche competition with a native clam Meretrix meretrix. The biodeposition, respiration, and excretion rates of M. mercenaria were determined seasonally using a sediment trap and a closed respirator in field. The biodeposition rates of M. mercenaria were 0.06-0.37 g/ (ind.·d), and the respiration rates were 0.31-14.66 mg/(ind.·d). The ammonia and phosphate excretion rates were 0.18-36.70 and 1.44-14.87 μg/(ind.·d), respectively. The hard clam M. mercenaria may discharge dry deposits up to 2.1×105 t, contribute 18.3 t ammonia and 9.0 t phosphate to culture ponds, and consume 7.9×103 t O2 from ponds annually. It suggested that the hard clam M. mercenaria might play an important role in pelagic-benthic coupling in pond ecosystem through biodeposition and excretion. A comparison of the key physiological parameters of the introduced clam M. mercenaria and the native clam Meretrix meretrix suggested that M. mercenaria had a niche similar to that of Meretrix meretrix in Shuangtaizi estuary and might have a potential competition with Meretrix meretrix for habitat and food if M. mercenaria species escaped from the culture pond or artificially released in estuarine ecosystem.

  15. Environmental contaminants in the aquatic bird food chain of an oil refinery wastewater pond in Wyoming

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Petroleum Hydrocarbons Based on higher PAH levels in sediment and vegetation, one would expect Pond 1 to pose a greater risk to wildlife than Pond 2. However, in...

  16. Can Environmental Education Actions Change Public Attitudes? An Example Using the Pond Habitat and Associated Biodiversity

    National Research Council Canada - National Science Library

    Sousa, Eunice; Quintino, Victor; Palhas, Jael; Rodrigues, Ana Maria; Teixeira, José

    2016-01-01

    .... The "Ponds with Life" environmental education project was developed to raise public awareness and engagement in the study of ponds by promoting the direct contact between the public and nature...

  17. DNR 100K Lakes - Fishing in the Neighborhood (FiN) Ponds

    Data.gov (United States)

    Minnesota Department of Natural Resources — This layer represents ponds included in DNR's Fishing in the Neighborhood (FiN) program. This program establishes local ponds to provide urban fishing opportunities...

  18. South Bay Salt Pond initial stewardship plan & related Bay Area restoration projects

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The Initial Stewardship Plan for the South Bay Salt Pond Restoration Project outlines a process to reduce the salinity of the existing salt ponds and to manage the...

  19. Valuating Ecosystem Services of Urban Ponds - case study from Bangladesh

    Science.gov (United States)

    Carle, Nina

    2016-04-01

    A climate risk assessment for the city of Barisal was carried out by a consultancy firm, financed by KfW Development Bank of Germany. Due to high dependencies on natural capital of people in developing countries they are facing high vulnerability when it comes to changes of the asset category 'natural capital' (here: urban ponds), whether due to the exposition on climate (change) related impacts, implemented measures or land use change. With a closer view on the city's assets, the question remained open to the author 1) Under current conditions, what is the demand for ecosystem services (ES) 2) What is the value of the benefits and the how much is the contribution to the city's welfare? 3) What are the future changes in the demand for ES? And what are the future changes on the supply side (pressures and threats to the ecosystem)? Methodology: The City of Barisal in Bangladesh has a calculated number of around 10.000 urban rain-fed ponds,representing 6.5% of the city area, which represents a huge natural water supply and gives the city its characteristic face. In August 2015 a user survey was conducted in the city of Barisal, in every ward (administrative unit), to determine the demand for ecosystem services related to urban ponds, evaluating over 600 ponds. The findings will present the huge variation of provisioning ecosystem services and an important regulating service, related to economic and domestic use, in a spatial resolution. It will be shown, how the importance of ES changes, by changing the unit of analysis (families or ponds or the city) and the importance for the livelihood of pond owners and users. A relationship between pond area(m2) and number of users was detected, also the role of compensation payments for the pond owners by the users. It will be shown how natural capital, privately and publicly owned,contributes in an important way in buffering unequal distribution of societies resources in the short- and long-run. However society's demand for ES

  20. Gradient zone boundary control in salt gradient solar ponds

    Energy Technology Data Exchange (ETDEWEB)

    Hull, John R. (Downers Grove, IL)

    1984-01-01

    A method and apparatus for suppressing zone boundary migration in a salt gradient solar pond includes extending perforated membranes across the pond at the boundaries, between the convective and non-convective zones, the perforations being small enough in size to prevent individual turbulence disturbances from penetrating the hole, but being large enough to allow easy molecular diffusion of salt thereby preventing the formation of convective zones in the gradient layer. The total area of the perforations is a sizable fraction of the membrane area to allow sufficient salt diffusion while preventing turbulent entrainment into the gradient zone.

  1. Arctic melt ponds and energy balance in the climate system

    Science.gov (United States)

    Sudakov, Ivan

    2017-02-01

    Elements of Earth's cryosphere, such as the summer Arctic sea ice pack, are melting at precipitous rates that have far outpaced the projections of large scale climate models. Understanding key processes, such as the evolution of melt ponds that form atop Arctic sea ice and control its optical properties, is crucial to improving climate projections. These types of critical phenomena in the cryosphere are of increasing interest as the climate system warms, and are crucial for predicting its stability. In this paper, we consider how geometrical properties of melt ponds can influence ice-albedo feedback and how it can influence the equilibria in the energy balance of the planet.

  2. Water quality characteristics of rivers and ponds in Japan

    Institute of Scientific and Technical Information of China (English)

    幸彦; 杜茂安; 玄正

    2004-01-01

    In Japan, various countermeasures have been taken to improve the water quality of public waters such as rivers and lakes. Though water quality has improved, it is still insufficient. In summer, eutrophication is seen in lakcs and inner bays, as well as rivers. As a countermeasure to prevent eutrophication, the removal treatment of nutrient salts such as nitrogen and phosphorus is done, in addition to organic substance elimination in the domestic sewerage system. This report will show the water quality characteristics of rivers and ponds in Japan. It is considered that these investigative results are effective when the water quality improvement of the stabilization ponds where eutrophication occurs are examined in China.

  3. Feed of Siamese fighting fish, Betta splendens, (Regan, 1910 in open pond: live and formulated diets

    Directory of Open Access Journals (Sweden)

    L. H. Sipaúba-Tavares

    Full Text Available Abstract The growth rate and percent survival of Betta splendens when submitted to formulated diet and live food treatments are evaluated. The three different diets were used and designated as: formulated diet (basal diet; live food diet (plankton and mixed diet (formulated diet with plankton. The live food diet contained plankton belonging to an open pond. High mortality was reported with live food (plankton treatment whereas higher percent survival occurred with formulated diet. Highest specific growth rate, weight gain and final weight were reported in the mixed diet treatment and were significantly different (p<0.01 from those in formulated diet and live food treatments. The gut contents of B. splendens in mixed diet and live food treatments comprised, Rotifera and Bacillariophyceae species in high percentages or rather, over 78% of total organisms. Lecane sp. was the most ingested zooplankton species by B. splendens in both treatments (mixed diet and live food, with the phytoplankton species Asterionella sp. and Melosira sp. respectively in mixed diet and in live food, respectively. Results indicated that the formulated diet influenced the water parameters dissolved oxygen, total suspended solids, total dissolved solids and pH. The live food in the open pond was not enough to improve the growth rate and percent survival of B. splendens. The growth performance of B. splendens; had the best results with mixed diet which was capable of maintaining species’s survival (82% and development in artificial conditions, benefiting the culture management of ornamental fish.

  4. Feed of Siamese fighting fish, Betta splendens, (Regan, 1910) in open pond: live and formulated diets.

    Science.gov (United States)

    Sipaúba-Tavares, L H; Appoloni, A M; Fernandes, J B K; Millan, R N

    2016-06-01

    The growth rate and percent survival of Betta splendens when submitted to formulated diet and live food treatments are evaluated. The three different diets were used and designated as: formulated diet (basal diet); live food diet (plankton) and mixed diet (formulated diet with plankton). The live food diet contained plankton belonging to an open pond. High mortality was reported with live food (plankton) treatment whereas higher percent survival occurred with formulated diet. Highest specific growth rate, weight gain and final weight were reported in the mixed diet treatment and were significantly different (psplendens in mixed diet and live food treatments comprised, Rotifera and Bacillariophyceae species in high percentages or rather, over 78% of total organisms. Lecane sp. was the most ingested zooplankton species by B. splendens in both treatments (mixed diet and live food), with the phytoplankton species Asterionella sp. and Melosira sp. respectively in mixed diet and in live food, respectively. Results indicated that the formulated diet influenced the water parameters dissolved oxygen, total suspended solids, total dissolved solids and pH. The live food in the open pond was not enough to improve the growth rate and percent survival of B. splendens. The growth performance of B. splendens; had the best results with mixed diet which was capable of maintaining species's survival (82%) and development in artificial conditions, benefiting the culture management of ornamental fish.

  5. The Selective Use of Hypochlorite to Prevent Pond Crashes for Algae-Biofuel Production.

    Science.gov (United States)

    Park, Sichoon; Van Ginkel, Steven W; Pradeep, Priya; Igou, Thomas; Yi, Christine; Snell, Terry; Chen, Yongsheng

    2016-01-01

    Although algae-biofuels have many advantages including high areal productivity, algae can be preyed upon by amoebas, protozoans, ciliates, and rotifers, particularly in open pond systems. Thus, these higher organisms need to be controlled. In this study, Chlorella kessleri was used as the algal culture and Brachionus calyciflorus as the source of predation. The effect of sodium hypochlorite (bleach) was tested with the goal of totally inhibiting the rotifer while causing minor inhibition to the alga. The 24-hr LC(50) for B. calyciflorus in spring water was 0.198 mg Cl/L while the 24-hr LC(50) for C. kessleri was 0.321 mg Cl/L. However, chlorine dissipates rapidly as the algae serves as reductant. Results showed a chlorine dosage between 0.45 to 0.6 mg Cl/L and a dosing interval of two hours created the necessary chlorine concentrations to inhibit predation while letting the algae grow; thus giving algae farmers a tool to prevent pond crashes.

  6. Asteroid Pond Mineralogy: View from a Cognate Clast in LL3 NWA 8330

    Science.gov (United States)

    Zolensky, M.; Le, L.

    2017-01-01

    All asteroids surfaces imaged at the cm-scale reveal the presence of pond deposits. These ponds are important because it is likely all asteroid sample return missions will sample them, being the safest (very flat) places to touch down. Therefore, it is essential to understand the differences between the material at the pond surfaces and the host asteroid. Fortunately, some fine-grained cognate lithologies in chondrites show sedimentary features indicating that they sample asteroid ponds.

  7. Using Hyperspectral Aircraft Remote Sensing to Support Ecosystems Services Research in New England Lakes and Ponds

    Science.gov (United States)

    Keith, D. J.; Milstead, B.; Walker, H.; Worthy, D.; Szykman, J.; Wusk, M.; Kagey, L.; Howell, C.; Snook, H.; Drueke, C.

    2010-12-01

    Northeastern lakes and ponds provide important ecosystem services to New England residents and visitors. These include the provisioning of abundant, clean water for consumption, agriculture, and industry as well as cultural services (recreation, aesthetics, and wilderness experiences) which enhance local economies and quality of life. Less understood, but equally important, are the roles that these lakes play in protecting all life through supportive services such as nutrient cycling. Nitrogen and phosphorus have a direct impact on the condition of fresh water lakes. Excesses of these nutrients can lead to eutrophication, toxic cyanobacteria blooms, decreased biodiversity, and loss of ecosystem function leading to a reduction in the availability and delivery of ecosystem services. In this study, we examined how variations in lake nutrient concentrations and phytoplankton pigment concentrations correlated with changes in the potential to provide cultural ecosystem services. Using a NASA Cessna 206 aircraft, hyperspectral data were collected during late summer 2009 from 55 lakes in New Hampshire, Massachusetts, Connecticut, and Rhode Island over a 2 day period. From the spectral data, algorithms were created which estimated concentrations of chlorophyll a, phycocyanin, and colored dissolved organic matter. The remotely sensed estimates were supplemented by in situ chlorophyll a, total nitrogen, total phosphorus and lake color data from 43 lakes sampled by field crews from the New England states. The purpose of this research is to understand how variations in lake nutrient concentrations and phytoplankton pigment concentrations correlate with changes in availability of cultural ecosystem services in the surveyed lakes. This dataset will be combined with information from the EPA National Lake Survey (2007), the EPA New England Lakes and Ponds Survey (2008) and the USGS SPARROW model to explore the association between lake condition and the provisioning of ecosystem

  8. 池塘分区集群式清洁养殖新模式的概念、原理与方法%A new model of partition cluster clean aquaculture in ponds:concept, principle and methods

    Institute of Scientific and Technical Information of China (English)

    丁建华; 赵文

    2014-01-01

    The concept, principle and methods of a new culture model-partition cluster clean culture in ponds ( PCCP) were discussed. Partition cluster clean culture in ponds is a new pond culture model of which is different from traditional polyculture in a pond. In condition of health culture, artificial feeding fishes were cultured in small scale zone names as high density fish culture zone in a pond. Fish fecal zone named as sewerage district were con-trolled to remove fecal timely, and the aim was to reducing residual feed and fish feces of which were discharged in-to sewage treatment zone outside the pond, to avoid water pollution and oxygen consumption. While changing most of the water areas in the pond is a water purification zone. And through the practice example of the kind of culture model, the existing problems and development prospects were also discussed. The results indicated that the features of this new pond culture model were three partitions of high density fish culture zone, sewerage district and water purification zone within the pond, in the model cultured fishes clusters, precise feeding, and remove fecal and rem-nant timely were carried out. Fish production is higher than that in traditional pond culture models, and achieves the purpose of saving water and reducing discharge.%对一种新的养殖模式———池塘分区集群式清洁养殖的概念、原理与方法进行了论述。池塘分区集群式清洁养殖( partition cluster clean aquaculture in ponds, PCCA)模式是一种不同于传统混养的池塘养殖新模式,即在健康养殖条件下将人工投喂的鱼类集群圈养于池塘小范围区域(即集群养殖区)中,通过控制鱼类粪便的排泄区域(沉淀排污区),做到及时将粪便清除到池塘外污水处理区,以降低鱼类粪便、残饵等对水体的污染及溶解氧消耗,使池塘中大部分水体区转变为水质净化区域,并通过该种养殖模式的实例,对其存在的问题和开

  9. Green Algae from Coal Bed Methane Ponds as a Source of Fertilizer for Economically Important Plants of Montana

    Science.gov (United States)

    Ogunsakin, O. R.; Apple, M. E.; Zhou, X.; Peyton, B.

    2016-12-01

    The Tongue River Basin of northeastern Wyoming and southeastern Montana is the location of natural gas reserves and coal bed methane (CBM) acreage. Although the water that emanates from CBM extraction varies with site, it is generally of higher quality than the waters produced by conventional oil and gas wells, in part because it is low in volatile organic compounds. However, since CBM water contains dissolved solids, including sodium (Na), bicarbonate (HCO3) and chloride (Cl) ions, the water must be treated before it can be discharged into the river or wetlands, or used for stock ponds or irrigation. Several ponds have been constructed to serve as a holding facility for CBM water. Algae from the CBM ponds of the Tongue River Basin have the potential to be utilized as fertilizer on economically important plants of Montana. Two very important crop plants of Montana are wheat, Triticum aestivum, and potatoes, Solanum tuberosum. To explore this potential, isolates of unicellular green algae (Chlorella sp.) from the CBM ponds were cultured in aerated vessels with Bold's Basic Growth Medium and natural and/or supplemental light. Algal biomass was condensed in and collected from a valved funnel, after which cell density was determined via light microscopy and a hemacytometer. Algal/water slurries with known nutrient contents were added to seedlings of hard winter wheat, T.aestivum, grown in a greenhouse for three months before harves. When compared to wheat provided with just water, or with water and a commercially available fertilizer, the wheat fertilized with algae had a higher chlorophyll content, more tillers (side shoots), and a higher ratio of influorescences (groups of flowers) per stem. In a related experiment, Ranger Russet seed potatoes, S. tuberosum were given just water, water and Hoagland's nutrient solution, or water with algae in order to compare aboveground growth and potato production among the treatments. The results of this study suggest that

  10. Geographical distribution of investment in small-scale rural fish ponds

    NARCIS (Netherlands)

    Bush, S.R.; Kosy, S.

    2007-01-01

    This article provides a detailed empirical study of investment patterns in small-scale rural aquaculture and its relation to pond location based on a systematic fish pond survey in Lao PDR. Nominal investment categories of fish ponds were created based on stocking rate, feed and water and then spati

  11. Food inputs, water quality and nutrient accumulation in integrated pond systems: A multivariate approach

    NARCIS (Netherlands)

    Nhan, D.K.; Milstein, A.; Verdegem, M.C.J.; Verreth, J.A.J.

    2006-01-01

    A participatory on-farm study was conducted to explore the effects of food input patterns on water quality and sediment nutrient accumulation in ponds, and to identify different types of integrated pond systems. Ten integrated agriculture-aquaculture (IAA) farms, in which ponds associate with fruit

  12. Production Responses of Channel Catfish to Minimum Daily Dissolved Oxygen Concentrations in Earthen Ponds

    Science.gov (United States)

    The purpose of this study was to determine the effects of the minimum daily dissolved oxygen (DO) concentration on production parameters of channel catfish Ictalurus punctatus in earthen ponds. Fifteen one-acre ponds (5 ponds per treatment) were managed as High Oxygen (minimum DO concentrations aver...

  13. Estimating the ratio of pond size to irrigated soybeans land in Mississippi: A case study

    Science.gov (United States)

    Although more on-farm storage ponds have been constructed in recent years to mitigate groundwater resources depletion in Mississippi, little effort has been devoted to estimating the ratio of pond size to irrigated crop land based on pond matric and its hydrological conditions. Knowledge of this ra...

  14. Estimating the ratio of pond size to irrigated soybean land in Mississippi: a case study

    Science.gov (United States)

    Ying Ouyang; G. Feng; J. Read; T. D. Leininger; J. N. Jenkins

    2016-01-01

    Although more on-farm storage ponds have been constructed in recent years to mitigate groundwater resources depletion in Mississippi, little effort has been devoted to estimating the ratio of on-farm water storage pond size to irrigated crop land based on pond metric and its hydrogeological conditions.  In this study, two simulation scenarios were chosen to...

  15. Performance and Modelling of a Highway Wet Detention Pond Designed for Cold Climate

    DEFF Research Database (Denmark)

    Vollertsen, Jes; Åstebøl, Svein Ole; Coward, Jan Emil

    2009-01-01

    A wet detention pond in Norway has been monitored for 12 months. The pond receives runoff from a highway with a traffic load of 42,000 average daily traffic. Hydraulic conditions in terms of inflow, outflow, and pond water level were recorded every minute. Water quality was monitored by volume...

  16. Oxygen transfer in marsh-pond-marsh constructed wetlands treating swine wastewater

    Science.gov (United States)

    Marsh-pond-marsh (M-P-M) constructed wetlands have been used to treat wastewater from swine anaerobic lagoons. To mitigate undesired ammonia emission from M-P-M, ponds were covered with floating wetlands (M-FB-M). The pond sections of the M-FB-M were covered with floating wetlands consisted of recyc...

  17. Food inputs, water quality and nutrient accumulation in integrated pond systems: A multivariate approach

    NARCIS (Netherlands)

    Nhan, D.K.; Milstein, A.; Verdegem, M.C.J.; Verreth, J.A.J.

    2006-01-01

    A participatory on-farm study was conducted to explore the effects of food input patterns on water quality and sediment nutrient accumulation in ponds, and to identify different types of integrated pond systems. Ten integrated agriculture-aquaculture (IAA) farms, in which ponds associate with fruit

  18. Data analysis protocol for using resistivity array as an early-warning wastewater pond leak detector

    Science.gov (United States)

    Typically, holding ponds are used to control runoff from concentrated animal feeding operations. The integrity of these holding ponds has come under increased scrutiny since subsurface leakage has the potential to affect soil and groundwater quality. Traditionally, ponds are monitored by installin...

  19. Heavy metal composition in stormwater and retention in ponds dependent on pond age, design and catchment type

    DEFF Research Database (Denmark)

    Egemose, Sara; Sønderup, Melanie J.; Grudinina, Anna

    2015-01-01

    . The concentrations varied considerably depending on the catchment type, with the highest concentrations coming from industrial areas and the lowest from uncultivated and rural areas. Ponds can effectively remove heavy metals in particulate forms through sedimentation processes, but the dissolved forms are more...... such as pH, oxygen and organic matter. Input of metals to the ponds was reflected in the sediment content, but not significantly for all heavy metals probably due to low or varying retention caused by mineralization and re-suspension. The heavy metal concentration in the outlets was reduced to non...

  20. Common culture practices for cyprinids in Asia.

    Science.gov (United States)

    Singh, T

    1997-01-01

    Cyprinids are the largest group of cultured freshwater fish and thus the most important from the aspect of fish-borne parasitic zoonoses. The common practices employed in the culture of this group are described to provide background information which may be used in the formulation of strategies for the control of these zoonoses. Only the common carp is cultured in monoculture: all the rest of the carp species are usually cultured in polyculture systems incorporating several species. Polyculture of cyprinids may be carried out in ponds, cages or in free range culture in natural or man-made water bodies, Polyculture of cyprinids is often integrated with agriculture, such as livestock, poultry or crop farming, utilizing byproducts of the agriculture activity, especially manure, as a source of nutrient for the fish pond. If precautions are not taken, this practice may provide an avenue for the transmission of fish borne parasites to man.

  1. Characterization of a Single Magnetotactic Bacterial Species from Devil's Bathtub, Mendon Ponds Park, Honeoye Falls, NY

    Science.gov (United States)

    Wagner, C.; Tarduno, J. A.; Stein, A.; Sia, E.

    2015-12-01

    Magnetotactic bacteria (MTB) belong to a lineage of prokaryotic bacteria that synthesize magnetosomes, single domain magnetic particles (typically magnetite or greigite) with an average size of 50 nanometers. MTB utilize magnetosomes through magnetotaxis, the alignment and movement along magnetic field lines to navigate towards preferred environmental conditions. MTB are sensitive to different environments and are thought to exhibit varying magnetosome morphologies, compositions, sizes, and quantities in regards to the environments which they inhabit. These characteristics allow MTB and magnetofossils (preserved magnetosomes) to be used as modern/paleoenvironmental recorders and biomarkers for environmental change(s). Devil's Bathtub (Mendon Ponds Park, Honeoye Falls, NY) is a meromictic glacial kettle pond surrounded by deciduous tree cover. Here we examine one species of MTB based on prominence of this particular morphology at this locale. Magnetotaxis and morphology of this species have been observed using light microscopy. Micrographs have also been taken using Transmission Electron Microscopy (TEM) to verify cell morphology and to determine magnetosome morphology. TEM and magnetic hysteresis measurements were done to find and test the composition of magnetosomes. In this study we also focus on DNA sequencing and characterization of this MTB, as there are few MTB species which have been DNA sequenced successfully. Data from these experiments are directly applicable to this up-and-coming area of research as it will aid in the understanding and correlation of magnetosome and magnetofossils with environmental characteristics.

  2. Characterising legacy spent nuclear fuel pond materials using microfocus X-ray absorption spectroscopy.

    Science.gov (United States)

    Bower, W R; Morris, K; Mosselmans, J F W; Thompson, O R; Banford, A W; Law, K; Pattrick, R A D

    2016-11-05

    Analysis of a radioactive, coated concrete core from the decommissioned, spent nuclear fuel cooling pond at the Hunterston-A nuclear site (UK) has provided a unique opportunity to study radionuclides within a real-world system. The core, obtained from a dividing wall and sampled at the fill level of the pond, exhibited radioactivity (dominantly (137)Cs and (90)Sr) heterogeneously distributed across both painted faces. Chemical analysis of the core was undertaken using microfocus spectroscopy at Diamond Light Source, UK. Mapping of Sr across the surface coatings using microfocus X-ray fluorescence (μXRF) combined with X-ray absorption spectroscopy showed that Sr was bound to TiO2 particles in the paint layers, suggesting an association between TiO2 and radiostrontium. Stable Sr and Cs sorption experiments using concrete coupons were also undertaken to assess their interactions with the bulk concrete in case of a breach in the coating layers. μXRF and scanning electron microscopy showed that Sr was immobilized by the cement phases, whilst at the elevated experimental concentrations, Cs was associated with clay minerals in the aggregates. This study provides a crucial insight into poorly understood infrastructural contamination in complex systems and is directly applicable to the UK's nuclear decommissioning efforts.

  3. Groundwater impact assessment report for the 284-WB Powerplant Ponds

    Energy Technology Data Exchange (ETDEWEB)

    Alexander, D.J.; Johnson, V.G.; Lindsey, K.A.

    1993-09-01

    As required by the Hanford Federal Facility Agreement and Consent Order (Tri-Party Agreement Milestone M-17-00A), this report assesses the impact of wastewater discharged to the 284-WB Powerplant Ponds on groundwater quality. The assessment reported herein expands upon the initial analysis conducted between 1989 and 1990 for the Liquid Effluent Study Final Project Plan.

  4. Sustainable aquaculture in ponds: Principles, practices and limits

    NARCIS (Netherlands)

    Bosma, R.H.; Verdegem, M.C.J.

    2011-01-01

    The global aquaculture production of crustaceans, shellfish and fish has to increase to satisfy the growing demand and also to compensate for the reduced capture from overexploited fisheries. Extending the area of brackish and fresh water ponds is constrained by the limited availability of land and

  5. Mapping peat morphology in sag pond with ground penetrating radar

    Science.gov (United States)

    Iryanti, Mimin; Nugraha, Harya Dwi; Setiawan, Tedy; Bijaksana, Satria

    2013-09-01

    In the tropics peat is commonly found in low-land areas. In certain condition, however, peat could also be found in high elevation, such as in sag ponds near fault zones. Information regarding thickness and morphology of peat in Sag Pond can be used to infer fault activities in the past. In this study, we attempt to identify the thickness and morphology of peat in a sag pond at Karyawangi Village near the Lembang fault, to the north of Bandung, West Java, Indonesia. We use ground penetrating radar (GPR) method with 250 Mhz antennae in several lines. The data were them processes using Reflexw software. The results show that in each survey line, peat layer is clearly identifiable. In some lines, the peat layer is continous while in some other, the peat layer is undulated. The peat layer in general in about 0.5 to 2 m thick. In conclusion, the GPR method with 250 Mhz antennae is suitable for mapping peat thickness and morphology in Sag Pond.

  6. Pathogen removal mechanisms in macrophyte and algal waste stabilization ponds

    NARCIS (Netherlands)

    Awuah, E.

    2006-01-01

    Waste stabilization ponds are recognized as the solution to domestic wastewater treatment in developing countries. This is because it is cheap, easy to construct and do not require high skilled labour. In the developing countries the objectives for wastewater treatment should put emphasis on pathoge

  7. Removal of Heavy Metals and PAH in Highway Detention Ponds

    DEFF Research Database (Denmark)

    Bentzen, Thomas Ruby; Larsen, Torben; Thorndahl, Søren Liedtke

    2005-01-01

    , which has been designed according to standard design criteria for several decades. The study will focus on heavy metals (Cd, Cr, Cu, Pb and Zn) and polyaromatic hydrocarbons (PAH). The long-term simulation of input of flow and pollution to the ponds will be a hind cast based on time series of historical...

  8. Pathogen removal mechanisms in macrophyte and algal waste stabilization ponds

    NARCIS (Netherlands)

    Awuah, E.

    2006-01-01

    Waste stabilization ponds are recognized as the solution to domestic wastewater treatment in developing countries. The use of such natural systems is considered to be very important. This is because it is cheap, easy to construct and they do not require high skilled labour. In the developing countri

  9. Operation of Stabilization Ponds in a Tropical Area

    Science.gov (United States)

    1974-10-01

    aeration rather than photosynthesis ( Eckenfelder , 1966). 3) Aerobic Pond - A shallow depression, approximately 18 inches deep, in which the suspended and...Vietnam", Civil Engineering, Vol. 39, Kay, 1969, pp. 47-49. Eckenfelder , W. W., Jr., Industrial Water Pollution Control, McGraw- ^ Hill Book Co

  10. Food web interactions and nutrients dynamics in polyculture ponds

    NARCIS (Netherlands)

    Rahman, M.M.

    2006-01-01

    Artificial feed and fertilizers are the main sources of nutrients supporting fish growth in aquaculture ponds. The majority of the added nutrients are lost to the sediment, where they are no longer available for natural food production. By increasing resuspension of the sediment through the introduc

  11. Water quality in hybrid catfish ponds after partial fish harvest

    Science.gov (United States)

    Intensification of United States catfish aquaculture involves hybrid catfish ('channel catfish Ictalurus punctatus x ' blue catfish I. furcatus) grown in ponds with abundant aeration and high feeding rates. High feeding rates cause water quality deterioration because most of the nitrogen, phosphorus...

  12. Pathogen removal mechanisms in macrophyte and algal waste stabilization ponds

    NARCIS (Netherlands)

    Awuah, E.

    2006-01-01

    Waste stabilization ponds are recognized as the solution to domestic wastewater treatment in developing countries. The use of such natural systems is considered to be very important. This is because it is cheap, easy to construct and they do not require high skilled labour. In the developing countri

  13. Carbohydrates in the waters of ponds of Ramanthuruthu Island, Cochin

    Digital Repository Service at National Institute of Oceanography (India)

    Sankaranarayanan, V.N.; Kumaran, S.; Balasubramanian, T.; Stephen, R.; Panampunnayil, S.U.

    Particulate and dissolved carbohydrates in 4 ponds of the Ramanthuruthu Island (9 degrees 58.5'N lat. and 76 degrees 15.4'E long.) were studied for 1 yr (1978-79). Particulate carbohydrate concentration varied from 0.2 to 2 mg/l. Dissolved...

  14. Coleman Revisited: School Segregation, Peers, and Frog Ponds

    Science.gov (United States)

    Goldsmith, Pat Rubio

    2011-01-01

    Students from minority segregated schools tend to achieve and attain less than similar students from White segregated schools. This study examines whether peer effects can explain this relationship using normative models and frog-pond models. Normative models (where peers become alike) suggest that minority schoolmates are a liability. Frog-pond…

  15. Phytoplankton productivity in newly dug fish ponds within Lake ...

    African Journals Online (AJOL)

    EJIRO

    Key words: phytoplankton, primary productivity, fish ponds, light-limitation, Uganda. ... options for poor farmers and increase their income while reducing their vulnerability and also improving land and water management (Briones et al., 2004). However much ... was estimated using chlorophyll-a method (Wetzel and Likens,.

  16. Lime enhanced chromium removal in advanced integrated wastewater pond system.

    Science.gov (United States)

    Tadesse, I; Isoaho, S A; Green, F B; Puhakka, J A

    2006-03-01

    The removal of trivalent chromium from a combined tannery effluent in horizontal settling tanks and subsequent Advanced Integrated Wastewater Pond System (AIWPS) reactors was investigated. The raw combined effluent from Modjo tannery had pH in the range of 11.2-12. At this pH, a trivalent chromium removal of 46-72% was obtained in the horizontal settling tanks after a one-day detention time. Trivalent chromium precipitated as chromium hydroxide, Cr(OH)3. 58-95% Cr(III) was removed in the advanced facultative pond (AFP) where the water column pH of 7.2-8.4 was close to pH 8, which is the optimum precipitation pH for trivalent chromium. Chromium removals in the secondary facultative pond (SFP) and maturation pond (MP) were 30-50% and 6-16%, respectively. With Cr(III) concentration of 0.2-0.8 mg/l in the final treated effluent, the AIWPS preceded by horizontal settling tanks produced effluent that could easily meet most of the current Cr(III) discharge limits to receive water bodies.

  17. Effects of light and microbial activity on the degradation of two fluoroquinolone antibiotics in pond water and sediment.

    Science.gov (United States)

    Lin, Juo-Shan; Pan, Hung-Yu; Liu, Shiu-Mei; Lai, Hong-Thih

    2010-07-01

    Enrofloxacin (ENR) and ciprofloxacin (CIP) are two fluoroquinolone (FQ) antibiotics widely used to treat diseases of human beings and cultured animals. These two FQs are usually detected in the effluent of municipal sewage plants and related aquatic environments. The purpose of this study was to understand the fates of ENR and CIP in aquaculture pond water and a sediment slurry in a laboratory-scale experiment. Effects of light and microbial activity on the degradation of these two FQs were investigated. Results indicated that natural irradiation plays a major role in the degradation of ENR and CIP in pond water and the sediment slurry. The 50 % dissipation times (DT(50)) with non-sterile treatment were 0.01 and 18.4 d for ENR, and 0.04 and 17.3 d for CIP in the water and sediment slurry, respectively. On the other hand, the degradation of ENR and CIP under dark conditions was slow or even hindered, and all of their DT(50) values exceeded 100 d. These two FQs degraded faster in the sediment slurry than in pond water under dark conditions. Artificial ultraviolet (UV) and fluorescence light had similar effects on the degradation of ENR in the pond water and sediment slurry. Degradation of CIP was faster with UV than with fluorescence light treatment, while no such difference was found for ENR degradation. CIP was a degradation product of ENR under both light and dark conditions, and DT(50) values for both compounds were shorter in the presence of light. The phenomenon of biodegradation was observed during degradation of CIP in the sediment slurry under natural light.

  18. Vertical segregation and phylogenetic characterization of ammonia-oxidizing bacteria and archaea in the sediment of a freshwater aquaculture pond

    Directory of Open Access Journals (Sweden)

    Shimin eLu

    2016-01-01

    Full Text Available Pond aquaculture is the major freshwater aquaculture method in China. Ammonia-oxidizing communities inhabiting pond sediments play an important role in controlling culture water quality. However, the distribution and activities of ammonia-oxidizing microbial communities along sediment profiles are poorly understood in this specific environment. Vertical variations in the abundance, transcription, potential ammonia oxidizing rate, and community composition of ammonia-oxidizing bacteria (AOB and ammonia-oxidizing archaea (AOA in sediment samples (0–50 cm depth collected from a freshwater aquaculture pond were investigated. The concentrations of the AOA amoA gene were higher than those of the AOB by an order of magnitude, which suggested that AOA, as opposed to AOB, were the numerically predominant ammonia-oxidizing organisms in the surface sediment. This could be attributed to the fact that AOA are more resistant to low levels of dissolved oxygen. However, the concentrations of the AOB amoA mRNA were higher than those of the AOA by 2.5–39.9-fold in surface sediments (0–10 cm depth, which suggests that the oxidation of ammonia was mainly performed by AOB in the surface sediments, and by AOA in the deeper sediments, where only AOA could be detected. Clone libraries of AOA and AOB amoA sequences indicated that the diversity of AOA and AOB decreased with increasing depth. The AOB community consisted of two groups: the Nitrosospira and Nitrosomonas clusters, and Nitrosomonas were predominant in the freshwater pond sediment. All AOA amoA gene sequences in the 0–2 cm deep sediment were grouped into the Nitrososphaera cluster, while other AOA sequences in deeper sediments (10–15 and 20–25 cm depths were grouped into the Nitrosopumilus cluster.

  19. Comparison of hydraulics and particle removal efficiencies in a mixed cell raceway and Burrows pond rearing system

    Science.gov (United States)

    Moffitt, Christine M.

    2016-01-01

    We compared the hydrodynamics of replicate experimental mixed cell and replicate standard Burrows pond rearing systems at the Dworshak National Fish Hatchery, ID, in an effort to identify methods for improved solids removal. We measured and compared the hydraulic residence time, particle removal efficiency, and measures of velocity using several tools. Computational fluid dynamics was used first to characterize hydraulics in the proposed retrofit that included removal of the traditional Burrows pond dividing wall and establishment of four counter rotating cells with appropriate drains and inlet water jets. Hydraulic residence time was subsequently established in the four full scale test tanks using measures of conductivity of a salt tracer introduced into the systems both with and without fish present. Vertical and horizontal velocities were also measured with acoustic Doppler velocimetry in transects across each of the rearing systems. Finally, we introduced ABS sinking beads that simulated fish solids then followed the kinetics of their removal via the drains to establish relative purge rates. The mixed cell raceway provided higher mean velocities and a more uniform velocity distribution than did the Burrows pond. Vectors revealed well-defined, counter-rotating cells in the mixed cell raceway, and were likely contributing factors in achieving a relatively high particle removal efficiency-88.6% versus 8.0% during the test period. We speculate retrofits of rearing ponds to mixed cell systems will improve both the rearing environments for the fish and solids removal, improving the efficiency and bio-security of fish culture. We recommend further testing in hatchery production trials to evaluate fish physiology and growth.

  20. THE OPTIMAL RATIO OF NILE TILAPIA (Oreochromis niloticus AND COMMON CARP (Cyprinus carpio FOR IMPROVING PRODUCTIVITY ON DEEP WATER POND

    Directory of Open Access Journals (Sweden)

    Imam Taufik

    2013-06-01

    Full Text Available Pond productivity can be increased by applied polyculture system in the deep pond. The purpose of this experiment is to examine the optimal ratio between nile tilapia and common carp, in order to increase the productivity. Nine concrete tanks (15 m2 with water depth of 2.2 m and were completed by water inlet, water outlet, and aeration. Both of nile tilapia and common carp with size ranging of 5-8 cm in total length were used. Stock density was 150 ind./m2. The difference ratio of both fish tilapia and carp of fish stocked as a treatment. The fish ratio this experiment were as followed: A 100%; B 80%:20%; C 60%:40%. Fish fed by pellet until at ad libitum. The duration of experiment was 100 days. Parameters such as survival, growth, and productivity were observed every ten days during the experiment period. Water quality parameters were also periodically observed. The results showed that survival of nile tilapia among the treatments were not significantly different (P>0.05 where survival of common carp at B treatment was better than C treatment (P<0.05. The highest of growth of absolute weight (94.86±2.85 g and total length (14.71±1 cm of nile tilapia at B treatment was found (P<0.05 where the best of growth of absolute weight (106.52±10.47 g and total length (11.57±1.78 cm of common carp was also found at B treatment (P<0.05. Biomass productivity at B treatment was the highest compared with A treatment (P<0.05. Combination between polyculture and the deep water pond technology could increase productivity. The polyculture system and the deep water pond technology would be able to keep constant water quality within in the threshold accordance with the regulation for fish culture.

  1. Bioaccumulation of heavy metals in fauna from wet detention ponds for stormwater runoff

    DEFF Research Database (Denmark)

    Stephansen, Diana; Nielsen, Asbjørn Haaning; Hvitved-Jacobsen, Thorkild;

    2012-01-01

    Stormwater detention ponds remove pollutants e.g. heavy metals and nutrients from stormwater runoff. These pollutants accumulate in the pond sediment and thereby become available for bioaccumulation in fauna living in the ponds. In this study the bioaccumulation was investigated by fauna samples...... from 5 wet detention ponds for analyses of heavy metal contents. Five rural shallow lakes were included in the study to survey the natural occurrence of heavy metals in water-dwelling fauna. Heavy metal concentrations in water-dwelling fauna were generally found higher in wet detention ponds compared...

  2. Elimination and accumulation of polycyclic aromatic hydrocarbons (PAHs) in urban stormwater wet detention ponds

    DEFF Research Database (Denmark)

    Istenič, Daria; Arias, Carlos Alberto; Matamoros, Victor

    2011-01-01

    The concentrations of polycyclic aromatic hydrocarbons (PAHs) in water and sediments of seven wet detention ponds receiving urban stormwater were investigated. The ponds comprised traditional wet detention ponds with a permanent wet volume and a storage volume as well as ponds that were expanded...... concentrations in the sediments integrated the pollutant load over time. Pond systems expanded with sand filters and other technologies to enhance removal of micropollutants consistently had concentrations of PAHs in the effluents below the detection level. © IWA Publishing 2011....

  3. Distribution and Diversity of Oligochaetes in Selected Ponds of Thiruvananthapuram District, Kerala, South India

    Directory of Open Access Journals (Sweden)

    M. S. Ragi

    2014-01-01

    Full Text Available The present study was carried out to evaluate the distribution and diversity of oligochaete fauna in selected ponds of Thiruvananthapuram district in Kerala, South India. The sediment samples were collected from three ponds seasonally during the period December 2006 to November 2008. In the study, 10 oligochaete species which belong to 8 genera were identified in three selected ponds. These include Dero digitata, Dero nivea, Dero obtusa, Pristina longiseta, Aulophorus furcatus, Stylaria fossularis, Chaetogaster spp., Aeolosoma spp., Tubifex tubifex and Limnodrilus hoffmeisteri. Tubifex tubifex and Limnodrilus hoffmeisteri are the pollution-indicator oligochaete species identified in the fresh water ponds, which reveals that the studied ponds are subjected to pollution.

  4. Regulation of water quality and growth characteristics of indoor raceway culture of Litopenaeus vannamei

    Institute of Scientific and Technical Information of China (English)

    ZANG Weiling; YANG Ming; DAI Xilin; HOU Wenjie; LIU Yongshi; DING Fujiang

    2009-01-01

    Two modes of regulating the water quality of experimental ponds in indoor raceway culture of Litopenaeus vannamei were evaluated using simple water treatment facilities. A self-made water purifying net, aeration stone, composite microbe preparation, and Ceratophyllum demersum were placed in the experimental ponds and the culture water was circulated along the raceway inside the pond using a paddle wheel aerator. In addition, the water quality in the experimental pond was improved by draining effluent from the pipeline at the bottom of ponds 7 and 8 (mode I) and exchanging the circulating water in pond 10 (mode II) with the reservoir water in pond 9 using a pump and pipeline. The water quality in the experimental ponds was similar in response to regulation using mode I or mode II. Water quality parameters in the experimental ponds were controlled within a suitable range by simple facilities during culture period without using any chemical treatments. The rich content of dissolved oxygen was maintained by the circular flow and continuous aeration of the pond water. The respective average values of the main water parameters in experimental ponds 7 and 10 in response to regulation of the water quality using modes I and II were as follows: pH 8.17 and 7.99; DO 5.16 mg/L and 5.97 mg/L; CODMn 18.45 and 12.61 mg/L; TAN (NH_3-N) 0.854 mg/L (0.087 mg/L) and 0.427 mg/L (0.012 mg/L); NO_2-N 0.489 mg/L and 0.337 mg/L. Moreover, the average body length and body weight of harvested shrimp of pond 7 and pond 10 were 7.56 cm and 8.99 cm, 5.10 g and 8.33 g, respectively. Furthermore, the survival rate, average biomass yield and average condition factor of the shrimp harvested were 70% and 60%, 2.54 kg/m~2 and 2.14 kg/m~2, and 0.675 g/cm and 0.927 g/cm, respectively. Linear equations describing the relationship between body length and culture time and cubic or power functions describing the relationship between body weight and body length were obtained based on evaluation of the

  5. Effects of pond partition on characteristics of algae and water quality in pond located at high latitudes; Anteichi wo secchishita kanreichiike no suishitsu henka to sorui tokusei

    Energy Technology Data Exchange (ETDEWEB)

    Li, J. [Yamato Setsubi Construction Co. Ltd., Gunma (Japan); Kuroda, M. [Gunma University, Gunma (Japan). Faculty of Engineering; Wang, B. [Harbin Architectural and Civil Engineering Institute, Harbin (China). Water Pollution Control Research Center

    1995-10-10

    Characteristics of algae and water quality were studied at a pond located in high latitudes. Domestic and industrial wastewaters discharged are treated through different type stabilization ponds made by enclosing a part of the pond to remove BOD{sub 5}, COD{sub cr} and nutrients. Effects of the pond partition on the dominance species of algae and water quality were studied. During the cold term (-20{degree}C - -5{degree}C), Cryptomonas, Chlamydomonas and Euglena were dominance species in the pond. While Euglena, which may be grown by uptaking organic material was the dominance one in the stabilization pond, and its population increased in falling temperature. It plays an important role for removal of BOD{sub 5} and COD{sub cr}. On the other hand, during the warm term (15{degree}C - 30{degree}C), dominance species were Cyclotella, Chlorella and Microcystis in the pond and Scenedesmus obliqnus in facultative ponds of the stabilization ponds. Microcystis and Scenedesmus obliqnus would uptake NH4{sup +}-N truly. Removal of NH4{sup +}-N and PO4{sup 3-}-P depends on the concentration of Chl.a. The relationship between NH4{sup +}-N and PO4{sup 3-}-P removal and the concentrations of Chl.a was obtained. 11 refs., 8 figs., 3 tabs.

  6. Seasonal Variations and Assessment of Water Quality of Nagchoon Pond of Khandwa District (M. P. India

    Directory of Open Access Journals (Sweden)

    Saroj Mahajan

    2014-12-01

    Full Text Available “ SAVE WATER , SAVE LIFE.” Water is basic unit of life for all living organisms at this planet. Water is essential for drinking, domestic, irrigation and industries purposes. The Khandwa District is including in hot climatic region suffering from water crises whole year especially in summer season. The sources of potable water are limited in comparison to population of Khandwa. The important source of potable water is Nagchoon pond. In recent time a steady deterioration in the quality of fresh water resources is following the wake up of population explosion, consequent urbanization and rapid industrial development, cultural exploitation. Physico-chemical parameters have been studied from July 2008 to june 2010.the results showed that the chloride, nitrate, phosphate exceeding permissible limit so water body inclined towards eutrophication. Therefore, the Conservation and management of this water body is very much required.

  7. Fatty acids from high rate algal pond's microalgal biomass and osmotic stress effects.

    Science.gov (United States)

    Drira, Neila; Dhouibi, Nedra; Hammami, Saoussen; Piras, Alessandra; Rosa, Antonella; Porcedda, Silvia; Dhaouadi, Hatem

    2017-11-01

    The extraction of oil from a wild microalgae biomass collected from a domestic wastewater treatment facility's high rate algal pond (HRAP) was investigated. An experiment plan was used to determine the most efficient extraction method, the optimal temperature, time and solvent system based on total lipids yield. Microwave-assisted extraction was the most efficient method whether in n-hexane or in a mixture of chloroform/methanol compared to Soxhlet, homogenization, and ultrasounds assisted extractions. This same wild biomass was cultivated in a photobioreactor (PBR) and the effect of osmotic stress was studied. The lipids extraction yield after 3days of stress increased by more than four folds without any significant loss of biomass, however, the quality of extracted total lipids in terms of saturated, monounsaturated and polyunsaturated fatty acids was not affected by salinity change in the culture medium. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Unusually High Archaeal Diversity in a Crystallizer Pond, Pomorie Salterns, Bulgaria, Revealed by Phylogenetic Analysis

    Directory of Open Access Journals (Sweden)

    Margarita Kambourova

    2016-01-01

    Full Text Available Recent studies on archaeal diversity in few salterns have revealed heterogeneity between sites and unique structures of separate places that hinder drawing of generalized conclusions. Investigations on the archaeal community composition in P18, the biggest crystallizer pond in Pomorie salterns (PS (34% salinity, demonstrated unusually high number of presented taxa in hypersaline environment. Archaeal clones were grouped in 26 different operational taxonomic units (OTUs assigned to 15 different genera from two orders, Halobacteriales and Haloferacales. All retrieved sequences were related to culturable halophiles or unculturable clones from saline (mostly hypersaline niches. New sequences represented 53.9% of archaeal OTUs. Some of them formed separate branches with 90% similarity to the closest neighbor. Present results significantly differed from the previous investigations in regard to the number of presented genera, the domination of some genera not reported before in such extreme niche, and the identification of previously undiscovered 16S rRNA sequences.

  9. Isolation and characterization of a new Methanosarcina mazei strain GFJ07 from a mountain forest pond

    Directory of Open Access Journals (Sweden)

    Yi, Y.

    2012-01-01

    Full Text Available Aims: A new methanogenic strain, named GFJ07, was isolated from a pond of mountain forests in Guangxi, China. Cells grown in liquid culture tended to form aggregates with pseudosarcina-like or irregular shape.Methodology and Results: The optimum temperature, pH and NaCl concentration were 35 ℃, 7.0 and 0.5%, respectively. The isolate used methanol, trimethylamine, acetate and H2-CO2 as substrates. Analysis of the 16S rDNA sequences revealed strain GFJ07 showed the highest sequence similarity of 99.9% to Methanosarcina mazei.Conclusion, significance and impact of study: The cells were Gram positive and nonmotile. Most of single cell grew as a sausage-like clinder about 0.5 μm in diameter and 1.0 μm in length.

  10. Fine-scale urbanization affects Odonata species diversity in ponds of a megacity (Paris, France)

    Science.gov (United States)

    Jeanmougin, Martin; Leprieur, Fabien; Loïs, Grégoire; Clergeau, Philippe

    2014-08-01

    Current developments in urban ecology include very few studies focused on pond ecosystems, though ponds are recognized as biodiversity hotspots. Using Odonata as an indicator model, we explored changes in species composition in ponds localized along an urban gradient of a megacity (Paris, France). We then assessed the relative importance of local- and landscape-scale variables in shaping Odonata α-diversity patterns using a model-averaging approach. Analyses were performed for adult (A) and adult plus exuviae (AE) census data. At 26 ponds, we recorded 657 adults and 815 exuviae belonging to 17 Odonata species. The results showed that the Odonata species assemblage composition was not determined by pond localization along the urban gradient. Similarly, pond characteristics were found to be similar among urban, suburban and periurban ponds. The analyses of AE census data revealed that fine-scale urbanization (i.e., increased density of buildings surrounding ponds) negatively affects Odonata α-diversity. In contrast, pond localization along the urban gradient weakly explained the α-diversity patterns. Several local-scale variables, such as the coverage of submerged macrophytes, were found to be significant drivers of Odonata α-diversity. Together, these results show that the degree of urbanization around ponds must be considered instead of pond localization along the urban gradient when assessing the potential impacts of urbanization on Odonata species diversity. This work also indicates the importance of exuviae sampling in understanding the response of Odonata to urbanization.

  11. Groundwater monitoring plan for the Hanford Site 216-B-3 pond RCRA facility

    Energy Technology Data Exchange (ETDEWEB)

    Barnett, D.B.; Chou, C.J.

    1998-06-01

    The 216-B-3 pond system was a series of ponds for disposal of liquid effluent from past Hanford production facilities. In operation since 1945, the B Pond system has been a RCRA facility since 1986, with Resource Conservation and Recovery Act (RCRA) interim-status groundwater monitoring in place since 1988. In 1994, discharges were diverted from the main pond, where the greatest potential for contamination was thought to reside, to the 3C expansion pond. In 1997, all discharges to the pond system were discontinued. In 1990, the B Pond system was elevated from detection groundwater monitoring to an assessment-level status because total organic halogens and total organic carbon were found to exceed critical means in two wells. Subsequent groundwater quality assessment failed to find any specific hazardous waste contaminant that could have accounted for the exceedances, which were largely isolated in occurrence. Thus, it was recommended that the facility be returned to detection-level monitoring.

  12. Surface and subsurface soils at the Pond B dam: July 1998

    Energy Technology Data Exchange (ETDEWEB)

    Halverson, N.V.

    1999-12-03

    Pond B, 685-13G, is an inactive reactor cooling impoundment built in 1961 on the Savannah River Site (SRS). Between 1961 and 1964, Pond B received R-Reactor cooling water discharges that were contaminated with {sup 137}Cs, {sup 90}Sr and plutonium. Though the pond has not been used since 1964, radionuclides from the contaminated cooling water remain in the water and in the surface sediments of the pond. The current proposal to fix and repair the Pond B dam structure includes installing a new drain system and monitoring equipment. The dam will be reinforced with additional previous material on the downstream face of the dam. The objectives of this report are to describe the sampling methodology used during the July 1998 sampling event at the downstream face of the Pond B dam and in Pond B, present the results of the sampling event, and compare, where possible, these results to related risk-based standards.

  13. Effect of bottom reflectivity on the performance of a solar pond

    Energy Technology Data Exchange (ETDEWEB)

    Srinivasan, J.; Suha, A.

    1987-01-01

    The reflectivity of the bottom of a solar pond increases on account of the accumulation of dirt or the presence of undissolved salt. The effect of the reflection of the solar radiation at the bottom of the pond on the seasonal performance of the pond has been studied using a three zone model. The spectral reflectivity of dirt and common salt were measured in the laboratory and used in the analysis. The results obtained from the analysis show that the presence of dirt at the bottom of the pond does not affect the performance of the pond substantially. On the other hand, the presence of undissolved salt at the bottom of the pond results in substantial deterioration of the pond performance.

  14. Tangential flow ultrafiltration for detection of white spot syndrome virus (WSSV) in shrimp pond water.

    Science.gov (United States)

    Alavandi, S V; Ananda Bharathi, R; Satheesh Kumar, S; Dineshkumar, N; Saravanakumar, C; Joseph Sahaya Rajan, J

    2015-06-15

    Water represents the most important component in the white spot syndrome virus (WSSV) transmission pathway in aquaculture, yet there is very little information. Detection of viruses in water is a challenge, since their counts will often be too low to be detected by available methods such as polymerase chain reaction (PCR). In order to overcome this difficulty, viruses in water have to be concentrated from large volumes of water prior to detection. In this study, a total of 19 water samples from aquaculture ecosystem comprising 3 creeks, 10 shrimp culture ponds, 3 shrimp broodstock tanks and 2 larval rearing tanks of shrimp hatcheries and a sample from a hatchery effluent treatment tank were subjected to concentration of viruses by ultrafiltration (UF) using tangential flow filtration (TFF). Twenty to 100l of water from these sources was concentrated to a final volume of 100mL (200-1000 fold). The efficiency of recovery of WSSV by TFF ranged from 7.5 to 89.61%. WSSV could be successfully detected by PCR in the viral concentrates obtained from water samples of three shrimp culture ponds, one each of the shrimp broodstock tank, larval rearing tank, and the shrimp hatchery effluent treatment tank with WSSV copy numbers ranging from 6 to 157mL(-1) by quantitative real time PCR. The ultrafiltration virus concentration technique enables efficient detection of shrimp viral pathogens in water from aquaculture facilities. It could be used as an important tool to understand the efficacy of biosecurity protocols adopted in the aquaculture facility and to carry out epidemiological investigations of aquatic viral pathogens.

  15. Patterns of Assemblage Structure Indicate a Broader Conservation Potential of Focal Amphibians for Pond Management.

    Directory of Open Access Journals (Sweden)

    Elin Soomets

    Full Text Available Small freshwater ponds host diverse and vulnerable biotic assemblages but relatively few conspicuous, specially protected taxa. In Europe, the amphibians Triturus cristatus and Pelobates fuscus are among a few species whose populations have been successfully restored using pond restoration and management activities at the landscape scale. In this study, we explored whether the ponds constructed for those two target species have wider conservation significance, particularly for other species of conservation concern. We recorded the occurrence of amphibians and selected aquatic macro-invertebrates (dragonflies; damselflies; diving beetles; water scavenger beetles in 66 ponds specially constructed for amphibians (up to 8 years post construction and, for comparison, in 100 man-made ponds (created by local people for cattle or garden watering, peat excavation, etc. and 65 natural ponds in Estonia. We analysed nestedness of the species assemblages and its dependence on the environment, and described the co-occurrence patterns between the target amphibians and other aquatic species. The assemblages in all ponds were significantly nested, but the environmental determinants of nestedness and co-occurrence of particular species differed among pond types. Constructed ponds were most species-rich irrespective of the presence of the target species; however, T. cristatus was frequent in those ponds and rare elsewhere, and it showed nested patterns in every type of pond. We thus conclude that pond construction for the protected amphibians can serve broader habitat conservation aims in the short term. However, the heterogeneity and inconsistent presence of species of conservation concern observed in other types of ponds implies that long-term perspectives on pond management require more explicit consideration of different habitat and biodiversity values. We also highlight nestedness analysis as a tool that can be used for the practical task of selecting focal

  16. Zoo-heleoplankton structure in three artificial ponds of North-eastern Argentina.

    Science.gov (United States)

    Frutos, S M; Carnevali, R

    2008-09-01

    The aim of the present study was to compare the abundance and species richness of zoo-heleoplankton bigger than 53 microm in an annual cycle under similar climate conditions in three artificial ponds, in order to observe the changes during an annual cycle. Samples were taken monthly from June 1993 to July 1994 in Corrientes, Argentina. The first pond (A) was covered an 80% by Eichhornia crassipes (Mart.), the second one (B) with bloom of Microcystis aeruginosa (Kurtzing) and the last one (C) with organic matter deposited in the bottom. The water was more acidic at pond A, and the water at pond B contained more dissolved oxygen concentration than the water at the other two ponds. The zoo-heleoplankton densities varied between 20-1728 ind.l(-1) at pond A, 42-4082 ind.l(-1) at pond B and 148-2447 ind.l(-1) at pond C. The maximum zoo-heleoplankton abundance was found in the pond with cyanobacteria bloom during Autumn 1994 and the minimum abundance was found in the one with a predominance of E. crassipes. The rank of species richness was pond A > pond B > pond C. Rotifera was the most abundant group in pond A whereas the larval stages of Copepoda were abundant in the other two ponds. Anuraeopsis navicula Rousselt 1910 was the dominant population in the pond with macrophytes prevalence. Brachionus calyciflorus Pallas 1776 and larval stage of Copepoda had variable proportions in the pond with cyanobacteria bloom. Thermocyclops decipiens (Kiefer 1929) was present during the annual cycle only in the pond with organic matter deposited in the bottom. The succession of taxa was observed in the pond with coverage of aquatic macrophytes and with cyanobacteria bloom. Differences in species richness and low similarity in zoo-heleoplankton between ponds were determined by differences in the quality of the water in relation to the presence of macrophytes, cyanobacteria, organic matter deposited in the bottom and fish predation. Multiple regression analysis (stepwise) revealed that

  17. Community-based technology transfer in rural aquaculture: the case of mudcrab Scylla serrata nursery in ponds in Northern Samar, Central Philippines.

    Science.gov (United States)

    Baticados, Didi B; Agbayani, Renato F; Quinitio, Emilia T

    2014-12-01

    Finding aquaculture development approaches to open up livelihood opportunities for the rural poor and in mainstreaming smallholder fish farmers to reduce poverty remain a challenge. This paper examines the community-based technology transfer mechanism of mudcrab nursery in ponds and its socioeconomic impacts on smallholder mudcrab growers in Northern Samar, Philippines. Results indicated that the technology is a viable enterprise done by a straight culture system method, which is the rearing of crablets from aquaculture technologies.

  18. [Vibrio vulnificus infection outside of the fish ponds in northern Israel: acquisition in the "Einot Tzukim" springs near the Dead Sea].

    Science.gov (United States)

    Schlesinger, Yechiel; Ben-Shalom, Efrat; Raveh, David P; Yinnon, Amos M; Miskin, Hagit; Rudensky, Bernard

    2009-11-01

    Vibrio vulnificus is a Gram-negative bacterium that may cause severe skin and systemic infection after exposure of open wounds to contaminated water, especially in patients with underlying disease such as immune-deficiency, iron overload or end stage liver or renal disease. The V. vulnificus infection has been reported in Israel almost exclusively after exposure to Tilapia fish cultivated in fresh water fish ponds in northern Israel. The authors report the first case of V. vulnificus infection acquired in a nature reserve in southeastern Israel, with no connection to fish handling. A 14.5-years-old girl with transfusion-dependant thalassemia major presented with high fever and a rapidly progressive bullous cellulitis of the ankle. The infection occurred around a cut on the left lateral malleolus, after bathing in the fresh water ponds of Einot Tzukim (Ein Feshcha) in south-eastern Israel, and progressed despite the use of broad-spectrum antibiotics. Blood and wound cultures eventually yielded Vibrio vulnificus and appropriate treatment was commenced. The fever subsided after a few days but resolution of the local findings was very gradual and lasted for weeks. The presence of V. vulnificus in natural springs far from the northern artificial fish ponds broadens the danger of this infection. We find it prudent to advise people at risk for V. vulnificus infection, such as those suffering from immunedeficiency, iron overload and end stage liver or renal disease, to refrain from bathing in natural ponds whilst injured.

  19. Cdio as the educational and cultural structuring element in the dtu b.eng. in electronics programme

    DEFF Research Database (Denmark)

    Kjærgaard, Claus; Brauer, Peter; Andersen, Jens Christian

    2011-01-01

    as a part of the complex CDIO based education. The case used is the B.Eng. study in Electronics at the Technical University of Denmark (DTU) Implementing CDIO calls for many changes in the way that we build and document an program, having implemented CDIO at the B.Eng. program in electronics, it has been...... found that the normal public and internal course documentation platforms are insufficient to keep the large amount of information needed to describe the program as a whole, and the large amount of interaction between the individual courses, a master document describing the program has been developed...... to cover the first 4 semesters in the program, this paper is meant as an inspiration to others that might find this method beneficial. In todays modern and constantly changing society it must be expected that staff is constantly moving in and out between different research projects, while at the same time...

  20. Development of a Culturally Appropriate Bilingual Electronic App About Hepatitis B for Indigenous Australians: Towards Shared Understandings.

    Science.gov (United States)

    Davies, Jane; Bukulatjpi, Sarah; Sharma, Suresh; Caldwell, Luci; Johnston, Vanessa; Davis, Joshua Saul

    2015-06-10

    Hepatitis B is endemic in Indigenous communities in Northern Australia; however, there is a lack of culturally appropriate educational tools. Health care workers and educators in this setting have voiced a desire for visual, interactive tools in local languages. Mobile phones are increasingly used and available in remote Indigenous communities. In this context, we identified the need for a tablet-based health education app about hepatitis B, developed in partnership with an Australian remote Indigenous community. To develop a culturally appropriate bilingual app about hepatitis B for Indigenous Australians in Arnhem Land using a participatory action research (PAR) framework. This project was a partnership between the Menzies School of Health Research, Miwatj Aboriginal Health Corporation, Royal Darwin Hospital Liver Clinic, and Dreamedia Darwin. We have previously published a qualitative study that identified major knowledge gaps about hepatitis B in this community, and suggested that a tablet-based app would be an appropriate and popular tool to improve this knowledge. The process of developing the app was based on PAR principles, particularly ongoing consultation, evaluation, and discussion with the community throughout each iterative cycle. Stages included development of the storyboard, the translation process (forward translation and backtranslation), prelaunch community review, launch and initial community evaluation, and finally, wider launch and evaluation at a viral hepatitis conference. We produced an app called "Hep B Story" for use with iPad, iPhone, Android tablets, and mobile phones or personal computers. The app is culturally appropriate, audiovisual, interactive, and users can choose either English or Yolŋu Matha (the most common language in East Arnhem Land) as their preferred language. The initial evaluation demonstrated a statistically significant improvement in Hep B-related knowledge for 2 of 3 questions (P=.01 and .02, respectively) and

  1. Purification Of Water From Nsukka Water Pond Using Solar Still.

    Directory of Open Access Journals (Sweden)

    Ugwuoke E.C

    2015-08-01

    Full Text Available Abstract This work presents the analysis of a solar water distillation system. There is important need for good drinking water in the world today due to harmful effect of water borne diseases. Most water from rivers ponds seas are either salty or brackish and require purification before drinking. The water used in this work is collected from pond at Nsukka Urban and the experiment was performed at University of Nigeria Nsukka. Twenty litres of water was used for the experiment and 4 litres was obtained as the maximum volume after 10 days .The average temperature recorded during the experiment was 29C. The chemical and physical properties of the distillate correspond to world Health Organization Standard.

  2. Macroelements in the surface microlayer of water of urban ponds

    Directory of Open Access Journals (Sweden)

    Antonowicz Józef Piotr

    2016-03-01

    Full Text Available Analyses were conducted concerning the accumulation of four metals representing the group of macroelements, i.e. sodium, potassium, calcium and magnesium in two ponds located in the city of Słupsk. Water samples for chemical analyses were collected from the surface microlayer using a Garrett net. At the same time subsurface water samples were collected. Concentrations of metals were determined using a mass spectrometer. Generally, amounts of sodium, potassium, calcium and magnesium were similar in surface microlayer and subsurface water. Only in the case of potassium and calcium was low enrichment observed in the surface microlayer in one pond, while the greatest extent for magnesium enrichment was observed in the spring period.

  3. Bitumen recovery from surface mined oil sands recycle water ponds

    Energy Technology Data Exchange (ETDEWEB)

    Mikula, R.J.; Munoz, V.A.; Elliott, G. L. [Natural Resources Canada, CanmetENERGY, Devon, Alberta (Canada)

    2011-07-01

    In surface mined oil sands, high bitumen recovery can be achieved but tailings have accumulated over the years. Several technologies have been proposed for recovering bitumen from tailings, but because this bitumen carries high surfactant concentrations there have been processing problems. This paper presents the application of oxidized ore characterization and processing methods to process tailings pond bitumen. Laboratory tests were carried out to characterize bitumen samples coming from four different tailings sources and tests were run with caustic additive. Results showed that high caustic additions can be applied to surfactant rich tailings pond bitumen to avoid downstream froth treatment emulsion problems; the oxidation degree should be carefully monitored. This study demonstrated that the use of caustic additive, already used for oxidized ores, can be applied to treat the bitumen recovered from tailings streams.

  4. Outdoor cultivation of lutein-rich cells of Muriellopsis sp. in open ponds.

    Science.gov (United States)

    Blanco, Antonio M; Moreno, José; Del Campo, José A; Rivas, Joaquín; Guerrero, Miguel G

    2007-01-01

    The growth performance of the chlorophycean microalga Muriellopsis sp. outdoors in open tanks agitated with a paddlewheel and its ability to accumulate carotenoids have been evaluated throughout the year. The cells grown in the open system had free lutein as the main carotenoid, with violaxanthin, beta-carotene, and neoxanthin also present. Lutein content of the dry biomass ranged from 0.4 to 0.6%, depending on the growth and environmental conditions. In addition, the biomass of Muriellopsis sp. had a high content in both protein and lipids with about half of the fatty acids being of the polyunsaturated type, with alpha-linolenic acid accounting for almost 30% of the total fatty acids. The effect of determinant parameters on the performance of the cultures in open tanks was evaluated. Operating conditions that allow the maintenance of productive cultures were established under semicontinuous regime for 9 months throughout the year. Biomass and lutein yields in the open system were not far from those in closed tubular photobioreactors, and reached productivity values of 20 g dry biomass, containing around 100 mg lutein m(-2) day(-1) in summer. The outdoor culture of Muriellopsis sp. in open ponds thus represents a real alternative to established systems for the production of lutein.

  5. Understanding the biological activity of high rate algae ponds through the calculation of oxygen balances.

    Science.gov (United States)

    Arbib, Zouhayr; de Godos Crespo, Ignacio; Corona, Enrique Lara; Rogalla, Frank

    2017-06-01

    Microalgae culture in high rate algae ponds (HRAP) is an environmentally friendly technology for wastewater treatment. However, for the implementation of these systems, a better understanding of the oxygenation potential and the influence of climate conditions is required. In this work, the rates of oxygen production, consumption, and exchange with the atmosphere were calculated under varying conditions of solar irradiance and dilution rate during six months of operation in a real scale unit. This analysis allowed determining the biological response of these dynamic systems. The rates of oxygen consumption measured were considerably higher than the values calculated based on the organic loading rate. The response to light intensity in terms of oxygen production in the bioreactor was described with one of the models proposed for microalgae culture in dense concentrations. This model is based on the availability of light inside the culture and the specific response of microalgae to this parameter. The specific response to solar radiation intensity showed a reasonable stability in spite of the fluctuations due to meteorological conditions. The methodology developed is a useful tool for optimization and prediction of the performance of these systems.

  6. Implications of Fecal Bacteria Input from Latrine-Polluted Ponds for Wells in Sandy Aquifers

    Science.gov (United States)

    Knappett, Peter S. K.; McKay, Larry D.; Layton, Alice; Williams, Daniel E.; Alam, Md. J.; Huq, Md. R.; Mey, Jacob; Feighery, John E.; Culligan, Patricia J.; Mailloux, Brian J.; Zhuang, Jie; Escamilla, Veronica; Emch, Michael; Perfect, Edmund; Sayler, Gary S.; Ahmed, Kazi M.; van Geen, Alexander

    2012-01-01

    Ponds receiving latrine effluents may serve as sources of fecal contamination to shallow aquifers tapped by millions of tube-wells in Bangladesh. To test this hypothesis, transects of monitoring wells radiating away from four ponds were installed in a shallow sandy aquifer underlying a densely populated village and monitored for 14 months. Two of the ponds extended to medium sand. Another pond was sited within silty sand and the last in silt. The fecal indicator bacterium E. coli was rarely detected along the transects during the dry season and was only detected near the ponds extending to medium sand up to 7 m away during the monsoon. A log-linear decline in E. coli and Bacteroidales concentrations with distance along the transects in the early monsoon indicates that ponds excavated in medium sand were the likely source of contamination. Spatial removal rates ranged from 0.5-1.3 log10/m. After the ponds were artificially filled with groundwater to simulate the impact of a rain storm, E. coli levels increased near a pond recently excavated in medium sand, but no others. These observations show that adjacent sediment grain-size and how recently a pond was excavated influence how much fecal contamination ponds receiving latrine effluents contribute to neighboring groundwater. PMID:22191430

  7. Implications of fecal bacteria input from latrine-polluted ponds for wells in sandy aquifers.

    Science.gov (United States)

    Knappett, Peter S K; McKay, Larry D; Layton, Alice; Williams, Daniel E; Alam, Md J; Huq, Md R; Mey, Jacob; Feighery, John E; Culligan, Patricia J; Mailloux, Brian J; Zhuang, Jie; Escamilla, Veronica; Emch, Michael; Perfect, Edmund; Sayler, Gary S; Ahmed, Kazi M; van Geen, Alexander

    2012-02-07

    Ponds receiving latrine effluents may serve as sources of fecal contamination to shallow aquifers tapped by millions of tube-wells in Bangladesh. To test this hypothesis, transects of monitoring wells radiating away from four ponds were installed in a shallow sandy aquifer underlying a densely populated village and monitored for 14 months. Two of the ponds extended to medium sand. Another pond was sited within silty sand and the last in silt. The fecal indicator bacterium E. coli was rarely detected along the transects during the dry season and was only detected near the ponds extending to medium sand up to 7 m away during the monsoon. A log-linear decline in E. coli and Bacteroidales concentrations with distance along the transects in the early monsoon indicates that ponds excavated in medium sand were the likely source of contamination. Spatial removal rates ranged from 0.5 to 1.3 log(10)/m. After the ponds were artificially filled with groundwater to simulate the impact of a rain storm, E. coli levels increased near a pond recently excavated in medium sand, but no others. These observations show that adjacent sediment grain-size and how recently a pond was excavated influence the how much fecal contamination ponds receiving latrine effluents contribute to neighboring groundwater.

  8. Bacterial Selection from Shrimp Ponds for Degradation of Organic Matters

    OpenAIRE

    Powtongsook, S.; Chanpun, K.; Suntornsuk, W.

    2007-01-01

    Accumulation of ammonia, nitrite and hydrogen sulfide in a shrimp pond is generally caused by incomplete degradation of residual organic matters from overfeeding and from organic wastes released by shrimps. The phenomenon affects shrimp growth and survival rate. The objectives of this investigation were to screen for a bacterial strain able to digest organic residues and to evaluate the changes of residues by bacterial activities under natural conditions. The results from this work showed tha...

  9. MODELLING OF BACTERIAL SULPHATE REDUCTION IN ANAEROBIC PONDS : KINETIC INVESTIGATIONS

    OpenAIRE

    Harerimana, Casimir; Vasel, Jean-Luc; Jupsin, Hugues; Ouali, Amira

    2011-01-01

    The aim of the study was first to develop a simple and practical model of anaerobic digestion including sulphate-reduction in anaerobic ponds. The basic microbiology of our model consists of three steps, namely, acidogenesis, methanogenesis, and sulphate reduction. This model includes multiple reaction stoichiometry and substrate utilization kinetics. The second aim was to determine some kinetic parameters associated with this model. The values of these parameters for sulfidogenic bacteria ar...

  10. Specificity of zooplankton distribution in meteorite crater ponds (Morasko, Poland

    Directory of Open Access Journals (Sweden)

    Kuczyńska-Kippen N.

    2013-07-01

    Full Text Available This study was conducted in order to define the most important factors responsible for the zooplankton community structure inhabiting four meteorite crater ponds, located near the city of Poznań (Poland. The functioning of the meteorite craters resembled that of other small water bodies, where seasonality, physical-chemical features (mainly chlorophyll a concentration, pH and conductivity or biological parameters (lack of fish structured zooplankton assemblages. Rotifer species richness and abundance were highest in the autumn (12 species and 5107 ind L-1 on average, while crustaceans prevailed in the summer (12 and 201, respectively. The dominating structure also depended on the season, with pelagic species occurring in the spring and autumn and mainly littoral species in the summer. Moreover, the temporary nature of the craters caused great differentiation in zooplankton among ponds and favoured organisms adapted to living in astatic reservoirs, e.g. bdelloids, Daphnia pulex or Macrocyclops viridis. The co-occurrence of a variable community of small crustaceans with large daphnids indicated the existence of an additional ecological niche – a thick layer of sediments. Despite the occurrence of adverse living conditions (oxygen deficiencies and periodic drying and the eutrophic character of the waters, these ponds were a source of many rare species (e.g. Keratella paludosa, even in the status of dominants. Protective measures (a nature reserve allowed the area of meteorite fall to remain quite natural, despite its location close to an urban area.

  11. Interpretation of ponded infiltration data using numerical experiments

    Directory of Open Access Journals (Sweden)

    Dohnal Michal

    2016-09-01

    Full Text Available Ponded infiltration experiment is a simple test used for in-situ determination of soil hydraulic properties, particularly saturated hydraulic conductivity and sorptivity. It is known that infiltration process in natural soils is strongly affected by presence of macropores, soil layering, initial and experimental conditions etc. As a result, infiltration record encompasses a complex of mutually compensating effects that are difficult to separate from each other. Determination of sorptivity and saturated hydraulic conductivity from such infiltration data is complicated. In the present study we use numerical simulation to examine the impact of selected experimental conditions and soil profile properties on the ponded infiltration experiment results, specifically in terms of the hydraulic conductivity and sorptivity evaluation. The effect of following factors was considered: depth of ponding, ring insertion depth, initial soil water content, presence of preferential pathways, hydraulic conductivity anisotropy, soil layering, surface layer retention capacity and hydraulic conductivity, and presence of soil pipes or stones under the infiltration ring. Results were compared with a large database of infiltration curves measured at the experimental site Liz (Bohemian Forest, Czech Republic. Reasonably good agreement between simulated and observed infiltration curves was achieved by combining several of factors tested. Moreover, the ring insertion effect was recognized as one of the major causes of uncertainty in the determination of soil hydraulic parameters.

  12. Algal biofuels from wastewater treatment high rate algal ponds.

    Science.gov (United States)

    Craggs, R J; Heubeck, S; Lundquist, T J; Benemann, J R

    2011-01-01

    This paper examines the potential of algae biofuel production in conjunction with wastewater treatment. Current technology for algal wastewater treatment uses facultative ponds, however, these ponds have low productivity (∼10 tonnes/ha.y), are not amenable to cultivating single algal species, require chemical flocculation or other expensive processes for algal harvest, and do not provide consistent nutrient removal. Shallow, paddlewheel-mixed high rate algal ponds (HRAPs) have much higher productivities (∼30 tonnes/ha.y) and promote bioflocculation settling which may provide low-cost algal harvest. Moreover, HRAP algae are carbon-limited and daytime addition of CO(2) has, under suitable climatic conditions, the potential to double production (to ∼60 tonnes/ha.y), improve bioflocculation algal harvest, and enhance wastewater nutrient removal. Algae biofuels (e.g. biogas, ethanol, biodiesel and crude bio-oil), could be produced from the algae harvested from wastewater HRAPs, The wastewater treatment function would cover the capital and operation costs of algal production, with biofuel and recovered nutrient fertilizer being by-products. Greenhouse gas abatement results from both the production of the biofuels and the savings in energy consumption compared to electromechanical treatment processes. However, to achieve these benefits, further research is required, particularly the large-scale demonstration of wastewater treatment HRAP algal production and harvest.

  13. Operation of roof pond systems, considering its advantages and disadvantages

    Energy Technology Data Exchange (ETDEWEB)

    Noohi, Samira; Rezaei, Davood [Faculty of engineering, Zanjan University (Iran, Islamic Republic of)], email: noohi.sam@gmail.com, email: d_rezaei@znu.ac.ir

    2011-07-01

    With the coming shortage of fossil fuels it is important to develop energy efficient buildings to reduce both energy consumption and pollution at the same time. The roof pond system is a passive solar system which gathers heat from the sun and can distribute it to the living space to cool it or heat it by changing the operating cycle. Although not recent, this method has not been widely implemented due to certain limitations and the aim of this paper is to assess the different advantages and disadvantages of this system over other passive solar heating systems. This study showed that a roof pond has a low impact on the building, provides controllable energy delivery and variations in indoor temperature are low; however it requires an active solar system as a backup and vegetation can limit sunlight penetration. This study highlighted that the efficiency of the roof system pond depends on climate conditions and that it is best suited to lower latitude and low humidity areas.

  14. Onset of convective instabilities in under-ice melt ponds.

    Science.gov (United States)

    Hirata, Sílvia C; Goyeau, Benoît; Gobin, Dominique

    2012-06-01

    The onset of double-diffusive natural convection in under-ice melt ponds is investigated through a linear stability analysis. The three-layer configuration is composed by a fluid layer (melt pond) overlying a saturated porous medium (ice matrix), which in turn overlies another fluid layer (under-ice melt pond). Water density inversion is taken into account by adopting a density profile with a quadratic temperature dependence and a linear concentration dependence. We show that the key parameter affecting stability is the depth of the ice matrix, while the depths of the upper and lower fluid layers play a marginal role. A Hopf bifurcation is observed in the whole range of parameters studied, and the size of the convection cells depends on ice permeability. The influence of the external temperature gradient is investigated by means of the definition of an extra thermal parameter accounting for the relative position of the density maximum. It is shown that convection is favored by larger temperature gradients, which occur during Arctic summer.

  15. Effects of Stocking Density on Water Quality, Growth and Economic Benefits of Chinese Soft-shelled Turtle Pelodiscus sinensis in Ponds

    Institute of Scientific and Technical Information of China (English)

    Wei LI; Huaiyu DING; Fengyin ZHANG; Tanglin ZHANG; Jiashou LIU; Zhongjie LI

    2016-01-01

    The Chinese soft-shel ed turtle Pelodiscus sinensis is a high-valued freshwater species cultured in China. This study in-vestigated the effects of stocking density on water quality, growth performance and economic return of Pelodiscus sinensis cul-tured in ponds. P. sinensis were stocked at densities of 1 ind./m2 (LD: low stocking density) and 2 ind./m2 (HD: high stocking density) in 3 000-m2 ponds, with three replicate ponds for each density. P. sinensis juveniles were fed with a commercial dry pel et feed of 46% crude protein and minced fil et of silver carp ans cultured for 122 days. The results showed that the levels of total nitrogen (TN), total phosphorous (TP), Chlorophyl-a (Chl. a) and turbidity in LD treatment were significantly lower than those in HD treatment (P<0.05). The mean TN and TP concentration in LD treatment was 29.3% and 35.7% lower compared to the HD treatment at the end of the experiment, respectively. Mean survival rates, final weight, average growth rates and PER were significantly higher in LD treatment compared with the HD treatment (P<0.05), respectively. Production was significantly af-fected by stocking density, which was higher in HD treatment, but the net income was higher in LD treatment. The results sug-gest that turtles with mean weight 55.6 g rearing at a low stocking density (1 ind./m2) in ponds had a positive effect on overal economic return and was effective at improving turtle growth performance and water quality.

  16. Enhancing biomass energy yield from pilot-scale high rate algal ponds with recycling.

    Science.gov (United States)

    Park, J B K; Craggs, R J; Shilton, A N

    2013-09-01

    This paper investigates the effect of recycling on biomass energy yield in High Rate Algal Ponds (HRAPs). Two 8 m(3) pilot-scale HRAPs treating primary settled sewage were operated in parallel and monitored over a 2-year period. Volatile suspended solids were measured from both HRAPs and their gravity settlers to determine biomass productivity and harvest efficiency. The energy content of the biomass was also measured. Multiplying biomass productivity and harvest efficiency gives the 'harvestable biomass productivity' and multiplying this by the energy content defines the actual 'biomass energy yield'. In Year 1, algal recycling was implemented in one of the ponds (HRAPr) and improved harvestable biomass productivity by 58% compared with the control (HRAPc) without recycling (HRAPr: 9.2 g/m(2)/d; HRAPc: 5.8 g/m(2)/d). The energy content of the biomass grown in HRAPr, which was dominated by Pediastrun boryanum, was 25% higher than the control HRAPc which contained a mixed culture of 4-5 different algae (HRAPr: 21.5 kJ/g; HRAPc: 18.6 kJ/g). In Year 2, HRAPc was then seeded with the biomass harvested from the P. boryanum dominated HRAPr. This had the effect of shifting algal dominance from 89% Dictyosphaerium sp. (which is poorly-settleable) to over 90% P. boryanum in 5 months. Operation of this pond was then switched to recycling its own harvested biomass, which maintained P. boryanum dominance for the rest of Year 2. This result confirms, for the first time in the literature, that species control is possible for similarly sized co-occurring algal colonies in outdoor HRAP by algal recycling. With regard to the overall improvement in biomass energy yield, which is a critical parameter in the context of algal cultivation for biofuels, the combined improvements that recycling triggered in biomass productivity, harvest efficiency and energy content enhanced the harvested biomass energy yield by 66% (HRAPr: 195 kJ/m(2)/day; HRAPc: 118 kJ/m(2)/day). Copyright © 2013

  17. Renewable Water: Direct Contact Membrane Distillation Coupled With Solar Ponds

    Science.gov (United States)

    Suarez, F. I.; Tyler, S. W.; Childress, A. E.

    2010-12-01

    The exponential population growth and the accelerated increase in the standard of living have increased significantly the global consumption of two precious resources: water and energy. These resources are intrinsically linked and are required to allow a high quality of human life. With sufficient energy, water may be harvested from aquifers, treated for potable reuse, or desalinated from brackish and seawater supplies. Even though the costs of desalination have declined significantly, traditional desalination systems still require large quantities of energy, typically from fossil fuels that will not allow these systems to produce water in a sustainable way. Recent advances in direct contact membrane distillation can take advantage of low-quality or renewable heat to desalinate brackish water, seawater or wastewater. Direct contact membrane distillation operates at low pressures and can use small temperature differences between the feed and permeate water to achieve a significant freshwater production. Therefore, a much broader selection of energy sources can be considered to drive thermal desalination. A promising method for providing renewable source of heat for direct contact membrane distillation is a solar pond, which is an artificially stratified water body that captures solar radiation and stores it as thermal energy at the bottom of the pond. In this work, a direct contact membrane distillation/solar pond coupled system is modeled and tested using a laboratory-scale system. Freshwater production rates on the order of 2 L day-1 per m2 of solar pond (1 L hr-1 per m2 of membrane area) can easily be achieved with minimal operating costs and under low pressures. While these rates are modest, they are six times larger than those produced by other solar pond-powered desalination systems - and they are likely to be increased if heat losses in the laboratory-scale system are reduced. Even more, this system operates at much lower costs than traditional desalination

  18. The Use of the Schizonticidal Agent Quinine Sulfate to Prevent Pond Crashes for Algal-Biofuel Production.

    Science.gov (United States)

    Xu, Chunyan; Wu, Kangyan; Van Ginkel, Steve W; Igou, Thomas; Lee, Hwa Jong; Bhargava, Aditya; Johnston, Rachel; Snell, Terry; Chen, Yongsheng

    2015-11-17

    Algal biofuels are investigated as a promising alternative to petroleum fuel sources to satisfy transportation demand. Despite the high growth rate of algae, predation by rotifers, ciliates, golden algae, and other predators will cause an algae in open ponds to crash. In this study, Chlorella kessleri was used as a model alga and the freshwater rotifer, Brachionus calyciflorus, as a model predator. The goal of this study was to test the selective toxicity of the chemical, quinine sulfate (QS), on both the alga and the rotifer in order to fully inhibit the rotifer while minimizing its impact on algal growth. The QS LC50 for B. calyciflorus was 17 µM while C. kessleri growth was not inhibited at concentrations <25 µM. In co-culture, complete inhibition of rotifers was observed when the QS concentration was 7.7 µM, while algal growth was not affected. QS applications to produce 1 million gallons of biodiesel in one year are estimated to be $0.04/gallon or ~1% of Bioenergy Technologies Office's (BETO) projected cost of $5/gge (gallon gasoline equivalent). This provides algae farmers an important tool to manage grazing predators in algae mass cultures and avoid pond crashes.

  19. The Use of the Schizonticidal Agent Quinine Sulfate to Prevent Pond Crashes for Algal-Biofuel Production

    Directory of Open Access Journals (Sweden)

    Chunyan Xu

    2015-11-01

    Full Text Available Algal biofuels are investigated as a promising alternative to petroleum fuel sources to satisfy transportation demand. Despite the high growth rate of algae, predation by rotifers, ciliates, golden algae, and other predators will cause an algae in open ponds to crash. In this study, Chlorella kessleri was used as a model alga and the freshwater rotifer, Brachionus calyciflorus, as a model predator. The goal of this study was to test the selective toxicity of the chemical, quinine sulfate (QS, on both the alga and the rotifer in order to fully inhibit the rotifer while minimizing its impact on algal growth. The QS LC50 for B. calyciflorus was 17 µM while C. kessleri growth was not inhibited at concentrations <25 µM. In co-culture, complete inhibition of rotifers was observed when the QS concentration was 7.7 µM, while algal growth was not affected. QS applications to produce 1 million gallons of biodiesel in one year are estimated to be $0.04/gallon or ~1% of Bioenergy Technologies Office’s (BETO projected cost of $5/gge (gallon gasoline equivalent. This provides algae farmers an important tool to manage grazing predators in algae mass cultures and avoid pond crashes.

  20. Sediment particle size and initial radiocesium accumulation in ponds following the Fukushima DNPP accident.

    Science.gov (United States)

    Yoshimura, Kazuya; Onda, Yuichi; Fukushima, Takehiko

    2014-01-01

    This study used particle size analysis to investigate the initial accumulation and trap efficiency of radiocesium ((137)Cs) in four irrigation ponds, ~4-5 months after the Fukushima Dai-ichi nuclear power plant (DNPP) accident. Trap efficiency, represented by the inventory of (137)Cs in pond sediment to the inventory of radiocesium in soil surrounding the pond (i.e., total (137)Cs inventory), was less than 100% for all but one pond. Trap efficiency decreased as sediment particle size increased, indicating that sediments with a smaller particle size accumulate more (137)Cs. In ponds showing low trap efficiency, fine sediment containing high concentrations of (137)Cs appeared to be removed from the system by hydraulic flushing, leaving behind mostly coarse sediment. The results of this study suggest that sediment particle size can be used to estimate the initial accumulation and trap efficiency of (137)Cs in pond sediment, as well as the amount lost through hydraulic flushing.

  1. Environmental impacts of two kind of ponds for shrimp production at Northwest Mexico.

    Science.gov (United States)

    Gonzalez-Ocampo, Hector; Romero-Schmidt, Heidi; Serrano-Pinto, Vania; Arguelles, Cerafina; Salinas, Federico; Rodríguez, Antonio; Castellanos, Aradit; Ortega-Rubio, Alfredo

    2004-01-01

    Aquaculture offers a major opportunity for the economic development of Baja California Sur (BCS), Mexico. The severely limited freshwater supply and the geographic isolation of the state place limits on other productive activities. Despite the aridity, the natural vegetation of BCS is diverse and structurally complex with a high percentage (20%) of endemic species. In this work we compare the environmental impacts produced by two kinds of aquaculture systems: coastal ponds vs. inland ponds. Construction and operation of coastal ponds does not require destruction of the natural vegetation and, as is true for inland ponds. Coastal ponds are also compatible with conservation of mangroves, sea grasses and sensitive habitats for fish and mollusks. To reduce the negative impacts of aquaculture and to protect the vegetation of Baja California Sur, we recommend the use of coastal ponds for shrimp production.

  2. Experimental and modelling of Arthrospira platensis cultivation in open raceway ponds.

    Science.gov (United States)

    Ranganathan, Panneerselvam; Amal, J C; Savithri, S; Haridas, Ajith

    2017-10-01

    In this study, the growth of Arthrospira platensis was studied in an open raceway pond. Furthermore, dynamic model for algae growth and CFD modelling of hydrodynamics in open raceway pond were developed. The dynamic behaviour of the algal system was developed by solving mass balance equations of various components, considering light intensity and gas-liquid mass transfer. A CFD modelling of the hydrodynamics of open raceway pond was developed by solving mass and momentum balance equations of the liquid medium. The prediction of algae concentration from the dynamic model was compared with the experimental data. The hydrodynamic behaviour of the open raceway pond was compared with the literature data for model validation. The model predictions match the experimental findings. Furthermore, the hydrodynamic behaviour and residence time distribution in our small raceway pond were predicted. These models can serve as a tool to assess the pond performance criteria. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Nutrient availability limits biological production in Arctic sea ice melt ponds

    DEFF Research Database (Denmark)

    Sørensen, Heidi Louise; Thamdrup, Bo; Jeppesen, Erik

    2017-01-01

    Every spring and summer melt ponds form at the surface of polar sea ice and become habitats where biological production may take place. Previous studies report a large variability in the productivity, but the causes are unknown. We investigated if nutrients limit the productivity in these first......-year ice melt ponds by adding nutrients to three enclosures ([1] PO4 3−, [2] NO3 −, and [3] PO4 3− and NO3 −) and one natural melt pond (PO4 3− and NO3−), while one enclosure and one natural melt pond acted as controls. After 7–13 days, Chl a concentrations and cumulative primary production were between...... nutrient limitation in melt ponds. We also document that the addition of nutrients, although at relative high concentrations, can stimulate biological productivity at several trophic levels. Given the projected increase in first-year ice, increased melt pond coverage during the Arctic spring and potential...

  4. Survival dynamics of fecal bacteria in ponds in agricultural watersheds of the Piedmont and Coastal Plain of Georgia.

    Science.gov (United States)

    Jenkins, Michael B; Endale, Dinku M; Fisher, Dwight S; Adams, M Paige; Lowrance, Richard; Newton, G Larry; Vellidis, George

    2012-01-01

    Animal agriculture in watersheds produces manure bacteria that may contaminate surface waters and put public health at risk. We measured fecal indicator bacteria (commensal Escherichia coli and fecal enterococci) and manure pathogens (Salmonella and E. coli 0157:H7), and physical-chemical parameters in pond inflow, within pond, pond outflow, and pond sediments in three ponds in agricultural watersheds. Bishop Pond with perennial inflow and outflow is located in the Piedmont, and Ponds A and C with ephemeral inflow and outflow in the Coastal Plain of Georgia. Bromide and chloride tracer experiments at Bishop Pond reflected a residence time much greater than that estimated by two models, and indicated that complete mixing within Bishop Pond was never obtained. The long residence time meant that fecal bacteria were exposed to solar UV-radiation and microbial predation. At Bishop Pond outflow concentrations of fecal indicator bacteria were significantly less than inflow concentrations; such was not observed at Ponds A and C. Both Salmonella and E. coli 0157:H7 were measured when concomitant concentrations of commensal E. coli were below the criterion for surface water impairment indicating problems with the effectiveness of indicator organisms. Bishop Pond improved down stream water quality; whereas, Ponds A and C with ephemeral inflow and outflow and possibly greater nutrient concentrations within the two ponds appeared to be less effective in improving down stream water quality.

  5. Nitrogen transformations and removal mechanisms in algal and duckweed stabilisation ponds

    OpenAIRE

    Zimmo, O.

    2003-01-01

    This thesis describes the results of a comparative study of the performance of algae-based ponds (ABPs) and duckweed-based ponds (DBPs) for wastewater treatment, with emphasis on nitrogen transformations and removal mechanisms.Batch experiments simulating algae and duckweed ( Lemna gibba ) stabilisation ponds for domestic wastewater treatment were conducted to quantify the importance of various nitrogen removal mechanisms under controlled conditions of pH and DO. N-removal in both systems by ...

  6. Preface: conservation of european ponds-current knowledge and future needs

    OpenAIRE

    Miracle, Rosa; Oertli, Beat; Céréghino, Régis; Hull, Andrew P.

    2010-01-01

    Ponds are common elements of the landscape with an important role in the global processes of biosphere and biodiversity preservation. Recent research indicates that ecological characteristics of ponds are different from other inland water systems, but scientific knowledge is still insufficient and poor compared to lakes and rivers. Therefore, whilst indicators and conservation tools have been developed for most aquatic systems, there is also a gap between existing basic information on pond ec...

  7. Little Fish in a Big Pond--Time to Get Schooled!

    Science.gov (United States)

    Moye, Johnny J.

    2011-01-01

    One technique used by many who fish is to catch a fish in a creek or pond and then release it in a different pond. This satisfies the desire for sport, and it also serves to stock a pond that may need replenishment. Of course this restocking can be a traumatic experience for the new fish. To survive in the new environment, the fish must find its…

  8. Application of hazard analysis critical control point (HACCP) as a possible control measure for Opisthorchis viverrini infection in cultured carp (Puntius gonionotus).

    Science.gov (United States)

    Khamboonruang, C; Keawvichit, R; Wongworapat, K; Suwanrangsi, S; Hongpromyart, M; Sukhawat, K; Tonguthai, K; Lima dos Santos, C A

    1997-01-01

    Opisthorchiasis due to Opisthorchis viverrini and transmitted through infected freshwater cyprinoid fish (carps) affects more than 8 million people in Thailand, People's Democratic Republic of Lao, and Vietnam. The Hazard Analysis Critical Control Point (HACCP)-concept has been recommended by FAO and WHO to be included in programs to control foodborne trematode infections (FBT). HACCP is a multifactorial approach to control food hazards through surveillance of diseases, foods, and operations and education. This study describes the first attempt to apply HACCP to the prevention and control of Opisthorchis viverrini in pond culture carp (Puntius gonionotus). The experiment was designed and carried out by a multidisciplinary "HACCP team" including experts in the field of public health, parasitology, epidemiology, aquaculture, fisheries extension and fish inspection. The investigation was performed in two fish ponds in the District of Sun Pa Tong, Chiang Mai, Thailand. In the experimental pond, fish was cultured according to HACCP principles and compared with the control pond, which followed conventional aquaculture practices. Water supply to the pond, fish fry, fish feed and pond conditions during the growing period were identified as critical control points (CCPs). Hazards were identified and analyzed, as well as control measures, critical limits, monitoring procedures, corrective actions, and record keeping developed for each one of the above CCPs. Complete pond preparation, particularly aiming to eliminate contamination of pond water with O. viverrini eggs, fish infected with parasite meacercariae and the first intermediate host (Bithynia spp), was conducted. After the pond was filled with water, O. viverrini metacercaria-free fry were released into the pond. The preliminary results obtained indicate that HACCP-based principles applied to carp pond culture could be used as a strategy to prevent and control O. viverrini. Further studies should be undertaken aiming

  9. es on Strength Characteristics of Pond Ash Replaced Fibre Reinforced Pavement Quality Concrete

    Directory of Open Access Journals (Sweden)

    Anand G Patil

    2015-08-01

    Full Text Available Energy consumption and generation is increasing day by day due to rapid industrialization & urbanization. A major portion of the energy is generated by Thermal Power Plants. Pond ash (PA and other by-products from these plants are disposed in large quantities. Pond ash utilization helps to reduce the consumption of natural resources. Hence there is scope for using Pond ash as Fine Aggregate (FA. Use of alternative material in concrete such as industrial by-products like Coal Ash (Fly Ash and Pond Ash is eco-friendly. This study reports the results of experimental studies carried out on the use of Pond ash as Fine Aggregate (FA in concrete with and without fibre reinforcement. The properties of Pond Ash were compared to the standard sand. The pond ash added by weight is 10%,20%,30%,40%,50% and 60% respectively as replacement of FA in concrete and 2% low tensile steel fibre was used for reinforcement. Experiments carried out indicate that Pond ash as partial replacement of sand has beneficial effect on the mechanical properties. The strength properties are determined for various percentages (10-60% of replacement of Fine Aggregate with Pond ash with and without fibre reinforcement. The test results indicate that the optimum PA replacement is 20% for both the cases.

  10. Lethal and sublethal effects of embryonic and larval exposure of Hyla versicolor to Stormwater pond sediments.

    Science.gov (United States)

    Brand, Adrianne B; Snodgrass, Joel W; Gallagher, Matthew T; Casey, Ryan E; Van Meter, Robin

    2010-02-01

    Stormwater ponds are common features of modern stormwater management practices. Stormwater ponds often retain standing water for extended periods of time, develop vegetative characteristics similar to natural wetlands, and attract wildlife. However, because stormwater ponds are designed to capture pollutants, wildlife that utilize ponds might be exposed to pollutants and suffer toxicological effects. To investigate the toxicity of stormwater pond sediments to Hyla versicolor, an anuran commonly found using retention ponds for breeding, we exposed embryos and larvae to sediments in laboratory microcosms. Exposure to pond sediments reduced survival of embryos by approximately 50% but did not affect larval survival. Larvae exposed to stormwater pond sediment developed significantly faster (x = 39 days compared to 42 days; p = 0.005) and were significantly larger at metamorphosis (x = 0.49 g compared to 0.36 g; p road salt contributes to the degradation of stormwater pond habitat quality for amphibian reproduction and that future research should focus on understanding interactions among road salts and other pollutants and stressors characteristic of urban environments.

  11. On solar ponds: salty fare for the world's energy appetite

    Energy Technology Data Exchange (ETDEWEB)

    Edesess, M.

    1982-11-01

    It is shown how a uniquely simple salt-gradient solar-energy trap is proving an economical source of electricity and low-temperature heat at various sites around the world. Problems with solar ponds include the thickening of the surface layer despite grids of wave-suppressors; the economics of using solar ponds to generate power and desalt water depend largely on the ability to operate without a synthetic liner; and some solar ponds lose much more heat to the ground than predicted. It is concluded that development of solar ponds is likely to depend on energy demand.

  12. Temperature, thermal efficiency, and gradient performance from two seawater-SZ solar ponds

    Energy Technology Data Exchange (ETDEWEB)

    Collado, F.; Lowrey, P. (San Diego State Univ., CA (United States))

    1991-01-01

    This paper presents 10 months of experience with two seawater-SZ (Storage Zone) solar ponds operated as a source of warm seawater which could have been used in an adjacent mariculture facility. Observations and extensive temperature, gradient and efficiency data are presented. This work demonstrated operation of and heat extraction from seawater-SZ solar ponds over a much longer interval than in previous work. It confirmed that seawater-SZ solar ponds can consistently give useful temperature elevations. A few phenomena not characteristic of conventional solar ponds were identified and are discussed.

  13. Assessing metal pollution in ponds constructed for controlling runoff from reclaimed coal mines.

    Science.gov (United States)

    Miguel-Chinchilla, Leticia; González, Eduardo; Comín, Francisco A

    2014-08-01

    Constructing ponds to protect downstream ecosystems is a common practice in opencast coal mine reclamation. As these ponds remain integrated in the landscape, it is important to evaluate the extent of the effect of mine pollution on these ecosystems. However, this point has not been sufficiently addressed in the literature. The main objective of this work was to explore the metal pollution in man-made ponds constructed for runoff control in reclaimed opencast coal mines over time. To do so, we evaluated the concentration of ten heavy metals in the water, sediment, and Typha sp. in 16 runoff ponds ranging from 1 to 19 years old that were constructed in reclaimed opencast coal mines of northeastern Spain. To evaluate degree of mining pollution, we compared these data to those from a pit lake created in a local unreclaimed mine and to local streams as an unpolluted reference, as well as comparing toxicity levels in aquatic organisms. The runoff ponds showed toxic concentrations of Al, Cu, and Ni in the water and As and Ni in the sediment, which were maintained over time. Metal concentrations in runoff ponds were higher than in local streams, and macrophytes showed high metal concentrations. Nevertheless, metal concentrations in water and sediment in runoff ponds were lower than those in the pit lake. This study highlights the importance of mining reclamation to preserve the health of aquatic ecosystems and suggests the existence of chronic metal toxicity in the ponds, potentially jeopardizing pond ecological functions and services.

  14. Bacterial abundance and diversity in pond water supplied with different feeds

    Science.gov (United States)

    Qin, Ya; Hou, Jie; Deng, Ming; Liu, Quansheng; Wu, Chongwei; Ji, Yingjie; He, Xugang

    2016-10-01

    The abundance and diversity of bacteria in two types of ponds were investigated by quantitative PCR and Illumina MiSeq sequencing. The results revealed that the abundance of bacterial 16S rRNA genes in D ponds (with grass carp fed sudan grass) was significantly lower than that in E ponds (with grass carp fed commercial feed). The microbial communities were dominated by Proteobacteria, Cyanobacteria, Bacteroidetes, and Actinobacteria in both E and D ponds, while the abundance of some genera was significantly different between the two types of ponds. Specifically, some potential pathogens such as Acinetobacter and Aeromonas were found to be significantly decreased, while some probiotics such as Comamonadaceae unclassified and Bacillales unclassified were significantly increased in D ponds. In addition, water quality of D ponds was better than that of E ponds. Temperature, dissolved oxygen and nutrients had significant influence on bacterial communities. The differences in bacterial community compositions between the two types of ponds could be partially explained by the different water conditions.

  15. Modern carbonate microbialites from an asbestos open pit pond, Yukon, Canada.

    Science.gov (United States)

    Power, I M; Wilson, S A; Dipple, G M; Southam, G

    2011-03-01

    Microbialites were discovered in an open pit pond at an abandoned asbestos mine near Clinton Creek, Yukon, Canada. These microbialites are extremely young and presumably began forming soon after the mine closed in 1978. Detailed characterization of the periphyton and microbialites using light and scanning electron microscopy was coupled with mineralogical and isotopic analyses to investigate the mechanisms by which these microbialites formed. The microbialites are columnar in form (cm scale), have an internal spherulitic fabric (mm scale), and are mostly made of aragonite, which is supersaturated in the subsaline pond water. Initial precipitation is seen as acicular aragonite crystals nucleating onto microbial biomass and detrital particles. Continued precipitation entombs benthic diatoms (e.g. Brachysira vitrea), filamentous algae (e.g. Oedogonium sp.), dinoflagellates, and cyanobacteria. The presence of phototrophs at spherulite centers strongly suggests that these microbes play an important initial role in aragonite precipitation. Substantial growth of individual spherulites occurs abiotically through periodic precipitation of aragonite that forms concentric laminations around spherulite centers while pauses in spherulite growth allow for colonization by microbes. Aragonite associated with biomass (δ(13)C = -4.6‰ VPDB) showed a (13)C-enrichment of 0.8‰ relative to aragonite exhibiting no biomass (δ(13)C = -5.4‰ VPDB), which suggests a modest removal of isotopically light dissolved inorganic carbon by phototrophs. The combination of a low sedimentation rate, high calcification rate, and low microbial growth rate appears to result in the formation of these microbialites. The formation of microbialites at an historic mine site demonstrates that an anthropogenically constructed environment can foster microbial carbonate formation.

  16. Removal of nutrients and organic pollution load from pulp and paper mill effluent by microalgae in outdoor open pond.

    Science.gov (United States)

    Usha, M T; Sarat Chandra, T; Sarada, R; Chauhan, V S

    2016-08-01

    A mixed culture of microalgae, containing two Scenedesmus species, was analysed to determine its potential in coupling of pulp and paper mill effluent treatment and microalgal cultivation. Laboratory studies suggested that 60% concentration of wastewater was optimum for microalgal cultivation. A maximum of 82% and 75% removal of BOD and COD respectively was achieved with microalgal cultivation in outdoor open pond. By the end of the cultivation period, 65% removal of NO3-N and 71.29% removal of PO4-P was observed. The fatty acid composition of mixed microalgal culture cultivated with effluent showed the palmitic acid, oleic acid, linoleic acid and α-linolenic acid as major fatty acids. The results obtained suggest that pulp and paper mill effluent could be used effectively for cultivation of microalgae to minimise the freshwater and nutrient requirements.

  17. The short-term effects of biological nutrient Nualgi and diatom algaes on the water quality and phytoplankton in culture pond%Nualgi营养素、硅藻藻种对池塘水质和浮游植物的短期效应研究

    Institute of Scientific and Technical Information of China (English)

    毛梦哲; 李晓莉; 陶玲; 高毛林; 李谷

    2016-01-01

    In order to study the short-term effects of biological nutrient Nualgi on water quality and phytoplankton in fish-pond, we conducted continuous and regular surveys for three weeks on the phytoplankton community and the water quality indexes in 4 groups. The 4 groups were a Nualgi group(M1), an algae group(M2), a Nualgi and algae group(M3) and a control group( C) . The results showed that the pH, DO, TN, TP had no remarkable difference among the 4 groups. IP in group M1 and M3 were remarkably lower than group M2 and group C, meaning Nualgi can reduce IP in water. Levels of NH4 +-N, NO2 --N and CODMn in group M1, M2 and M3 were remarkably lower than that of group C, meaning Nualgi or algae can both reduce NH4 +-N, NO2 --N and CODMn to adjust water quality. During the test, we identified 186 species that belonged to 7 phyla and 109 genera. 86 species were Chlorophyta, 48 were Bacillariophyta, 27 were Cyanophyta, 17 were Euglenophyta, 3 were Dinophyta, 3 were Cryptophyta and 2 were Chrysophyta. Adding diatom algae or Nualgi can both promote the growth of Bacillariophyta and restrain the growth of Chlorophyta and Cyanophyta. In the test, Melosira granulata became the dominant algae in group M1, M2 and M3 but without group Coelastrum microporum and Crucigenia tetrapedia are the dominant algae in group C only. Scenedesmus quadricauda became the dominant algae in group M1, M2 and C. There were no remarkable difference between the 4 groups about the diversity index, and the Shannon-Wiener in-dex were all above 2. 00, which showed that the species diversity is abundant.%为探讨短期内Nualgi营养素对池塘水质和藻类群落结构的影响,本研究在池塘中的不透水有底帆布围隔内共设计了4个试验组,依次分别添加Nualgi营养素( M1组)、补充硅藻藻种( M2组)、同时添加Nualgi营养素并补充硅藻藻种( M3组)、不做任何处理的空白对照( C组)。经过近一个月的试验,结果显示:各组的pH值、DO、 TN

  18. Supplement and Consumption of Dissolved Oxygen and Their Seasonal Variations in Shrimp Pond

    Institute of Scientific and Technical Information of China (English)

    孙耀; 张淑芳; 陈聚法; 宋云利

    2001-01-01

    On the basis of the research of DO budget or kinetics in shrimp pond, the main influence process of DO and its seasonal variations are quantitatively described through redividing the budget process and modifying the quantitative method of the process. The percentages of oxygen demand of various processes in the total oxygen demand are different in shrimp cultivation seasons. It is showed that the dissolved oxygen demand of mini-organisms is the major affected factor of DO in this environment and approximately accounts for 64.1~74.1% of the total oxygen demand. In the early period of shrimp culture, the dissolved oxygen demand of allotrophic bacteria degrading organic matters is much lower than that of phytoplankton respiration. But in the midterrn and later period, it is about 50% of the total oxygen demand because of the higher water temperature and more serious self-pollution. The dissolved oxygen demand of sediment is lower and just 19.1~28.8%, while the percentage of shrimp oxygen demand is lower. The effect of phytoplankton on DO in shrimp culturing water has dualism. One is the oxygen producing process of photosynthesis and the other is the oxygen consumption process of respiration. It is estimated that the dissolved oxygen demand of phytoplankton respiration is approximately one-fifth of the oxygen produced by photosynthesis under normal illumination conditions. The dissolved oxygen demand of al lotrophic bacteria degrading organic matters and the total oxygen demand of sediment increase 4 times and 1.7 times respectively from the early period to the midterm and later period.Obviously, the DO of culturing water can be also greatly improved by controlling the selfpollution of organic matters during shrimp culture.

  19. BIOCIDE TREATMENT OF PONDS IN SCOTLAND TO ERADICATE SIGNAL CRAYFISH

    Directory of Open Access Journals (Sweden)

    PEAY S.

    2006-01-01

    Full Text Available This trial aimed to eradicate illegally introduced signal crayfish Pacifastacus leniusculus in the North Esk catchment, Scotland. Sites treated were (1 an isolated gravel-pit (c. 9,000 m3, with crayfish present for 6 years; (2 three dammed ponds, (c. 5,000 m3 and (3 a leaking, offline pond (c. 6,000 m3, with crayfish for two years. Preliminary toxicity tests with substrate present indicated doses. Treatment at sites (1 and (2 (in October 2004, water temperature 13°C comprised deoxygenation with sodium sulphite to stimulate emergence, then application of natural pyrethrum (Pyblast. Exposed margins were sprayed with Pyblast to prevent escapes. Crayfish mortality was high, but one survivor was seen after 5 days. Pyblast was applied from a tank with Na2SO3 residue, which subsequent investigation indicated reduced Pyblast below the target 0.1 mg l-1. Site (1 was re-treated (end October, target 0.15 mg l-1 Pyblast, no Na2SO3, 9°C. Mortality was confirmed using caged crayfish. Prior to treatment at site (2, throughflow was stopped and fish removed. Biomonitoring was carried out with freshwater shrimps Gammarus in the adjacent watercourse. Treatment of site (3 (December, target 0.2 mg l-1, 4°C necessitated continuous back-pumping of leakage for a 2-week recovery period to avoid contamination of the river downstream. Caged crayfish took up to 5 days for 100% mortality. No crayfish were found in a summer survey after the treatments with Pyblast alone, but were caught in the ponds with Na2SO3 pre-treatment. Monitoring is required for 2-5 years.

  20. Predicting salt advection in groundwater from saline aquaculture ponds

    Science.gov (United States)

    Verrall, D. P.; Read, W. W.; Narayan, K. A.

    2009-01-01

    SummaryThis paper predicts saltwater advection in groundwater from leaky aquaculture ponds. A closed form solution for the potential function, stream function and velocity field is derived via the series solutions method. Numerically integrating along different streamlines gives the location (or advection front) of saltwater throughout the domain for any predefined upper time limit. Extending this process produces a function which predicts advection front location against time. The models considered in this paper are easily modified given knowledge of the required physical parameters.

  1. ELECTROKINETIC DENSIFICATION OF COAL FINES IN WASTE PONDS

    Energy Technology Data Exchange (ETDEWEB)

    E. James Davis

    1999-12-18

    The objective of this research was to demonstrate that electrokinetics can be used to remove colloidal coal and mineral particles from coal-washing ponds and lakes without the addition of chemical additives such as salts and polymeric flocculants. The specific objectives were: Design and develop a scaleable electrophoresis apparatus to clarify suspensions of colloidal coal and clay particles; Demonstrate the separation process using polluted waste water from the coal-washing facilities at the coal-fired power plants in Centralia, WA; Develop a mathematical model of the process to predict the rate of clarification and the suspension electrical properties needed for scale up.

  2. Taxonomy Icon Data: Reeve's pond turtle [Taxonomy Icon

    Lifescience Database Archive (English)

    Full Text Available Reeve's pond turtle Chinemys reevesii Chordata/Vertebrata/Reptilia/etc Chinemys_reevesii_L.png Chinemys_reev...esii_NL.png Chinemys_reevesii_S.png Chinemys_reevesii_NS.png http://biosciencedbc.j...p/taxonomy_icon/icon.cgi?i=Chinemys+reevesii&t=L http://biosciencedbc.jp/taxonomy_icon/icon.cgi?i=Chinemys+reeve...sii&t=NL http://biosciencedbc.jp/taxonomy_icon/icon.cgi?i=Chinemys+reevesii&t=S http://biosciencedbc.jp/taxonomy_icon/icon.cgi?i=Chinemys+reevesii&t=NS ...

  3. Metabolic acceleration in the pond snail Lymnaea stagnalis?

    Science.gov (United States)

    Zimmer, Elke I.; Ducrot, V.; Jager, T.; Koene, J.; Lagadic, L.; Kooijman, S. A. L. M.

    2014-11-01

    Under constant environmental conditions, most animals tend to grow following the von Bertalanffy growth curve. Deviations from this curve can point to changes in the environment that the animals experience, such as food limitation when the available food is not sufficient or suitable. However, such deviations can also point to a phenomenon called metabolic acceleration, which is receiving increasing attention in the field of Dynamic Energy Budget (DEB) modeling. Reasons for such an acceleration are usually changes in shape during ontogeny, which cause changes in the surface area to volume ratio of the organism. Those changes, in turn, lead to changes in some of the model parameters that have length in their dimension. The life-history consequences of metabolic acceleration as implemented in the DEB theory are an s-shaped growth curve (when body size is expressed as a length measure) and a prolongation of the hatching time. The great pond snail Lymnaea stagnalis was earlier found to be food limited during the juvenile phase in laboratory experiments conducted under classical ecotoxicity test protocols. The pond snail has isomorphic shell growth but yet does not exhibit the expected von Bertalanffy growth curve under food limitation. When applying the standard DEB model to data from such life-cycle experiments, we also found that the hatching time is consistently underestimated, which could be a sign of metabolic acceleration. We here present an application of the DEB model including metabolic acceleration to the great pond snail. We account for the simultaneous hermaphroditism of the snail by including a model extension that describes the relative investment into the male and female function. This model allowed us to adequately predict the life history of the snail over the entire life cycle. However, the pond snail does not change in shape substantially after birth, so the original explanation for the metabolic acceleration does not hold. Since the change in shape

  4. New Anabaena and Nostoc cyanophages from sewage settling ponds

    Energy Technology Data Exchange (ETDEWEB)

    Hu, N.; Thiel, T.; Giddings, T.H., Jr.; Wolk, C.P.

    1981-10-15

    We have isolated, from sewage settling ponds, 16 cyanophages for heterocyst forming, filamentous cyanobacteria of the genera Anabaena and Nostoc. These phages fall into three groups based on morphology, host range, one-step growth curves, and restriction digests. On the basis of these criteria they can be distinguished from cyanophages A-1(L), A-4(L), N-1, and AN-10 which we received from other laboratories. Certain of the newly described phages are similar in morphology to the short-tailed LPP cyanophages, and others to the long-tailed AS cyanophages.

  5. Heat Contribution and Extraction from an Experimental Solar Pond

    OpenAIRE

    Pérez-Martos Vidal, Luis Ignacio

    2012-01-01

    El proyecto consiste en la extracción de calor de un Solar Pond (SP) mediante el uso de dos intercambiadores situados en el interior de él, los cuales estarán interconectados con un circuito el cual irá a un intercambiador de placas situado en el exterior del SP donde se realizará la extracción de calor del corriente caliente. Además de la extracción, se realizará una aportación de calor al sistema mediante el uso de un sistema de placas solares de 10 metros cuadrados de superficie. La radiac...

  6. Thaw pond dynamics and carbon emissions in a Siberian lowland tundra landscape

    Science.gov (United States)

    van Huissteden, Ko; Heijmans, Monique; Dean, Josh; Meisel, Ove; Goovaerts, Arne; Parmentier, Frans-Jan; Schaepman-Strub, Gabriela; Belelli Marchesini, Luca; Kononov, Alexander; Maximov, Trofim; Borges, Alberto; Bouillon, Steven

    2017-04-01

    Arctic climate change induces drastic changes in permafrost surface wetness. As a result of thawing ground ice bodies, ice wedge troughs and thaw ponds are formed. Alternatively, ongoing thaw may enhance drainage as a result of increased interconnectedness of thawing ice wedge troughs, as inferred from a model study (Liljedahl et al., 2016, Nature Geoscience, DOI: 10.1038/NGEO2674). However, a recent review highlighted the limited predictability of consequences of thawing permafrost on hydrology (Walvoord and Kurylyk, 2016, Vadose Zone J., DOI:10.2136/vzj2016.01.0010). Overall, these changes in tundra wetness modify carbon cycling in the Arctic and in particular the emissions of CO2 and CH4 to the atmosphere, providing a possibly positive feedback on climate change. Here we present the results of a combined remote sensing, geomorphological, vegetation and biogechemical study of thaw ponds in Arctic Siberian tundra, at Kytalyk research station near Chokurdakh, Indigirka lowlands. The station is located in an area dominated by Pleistocene ice-rich 'yedoma' sediments and drained thaw lake bottoms of Holocene age. The development of three types of ponds in the Kytalyk area (polygon centre ponds, ice wedge troughs and thaw ponds) has been traced with high resolution satellite and aerial imagery. The remote sensing data show net areal expansion of all types of ponds. Next to formation of new ponds, local vegetation change from dry vegetation types to wet, sedge-dominated vegetation is common. Thawing ice wedges and thaw ponds show an increase in area and number at most studied locations. In particular the area of polygon centre ponds increased strongly between 2010 and 2015, but this is highly sensitive to antecedent precipitation conditions. Despite a nearly 60% increase of the area of thawing ice wedge troughs, there is no evidence of decreasing water surfaces by increasing drainage through connected ice wedge troughs. The number of thaw ponds shows an equilibrium

  7. A witness to history : the reclamation of Suncor's Pond 1

    Energy Technology Data Exchange (ETDEWEB)

    Eisner, M.

    2010-09-15

    This article described the reclamation of Suncor Energy's very first oil sands tailings pond at Fort McMurray. What had been a tailings pond for the past 43 years years in now inhabited by animals and hundreds of thousands of trees and shrubs. Covering 220 hectares adjacent to the Athabasca River, Suncor's Pond 1 was part of the first commercial-scale oil sands operation in Canada. After decades in operation, the pond is being closed in a highly regulated environment with a considerable knowledge base of reclamation techniques, well-defined reclamation goals and clear land use targets. The initial design of the Pond 1 tailings storage facility consisted of a 12-metre high retention dyke built over Tar Island. Suncor adopted a 3-phase approach to accelerate reclamation activities. In phase 1, the northern half of the pond began receiving reclamation material in 2007. In phase 2, the southern half of the pond continued to receive tailings while the phase 1 area underwent surface reclamation. Phase 3 consisted of a small area of soft tailings that was mechanically stabilized using geo-grid and tailings sand, and was the last area to undergo surface reclamation. Once the water and fine tailings had been removed, the pond was filled with 30 million tonnes of clean sand in 2009. Topsoil was then placed on the pond so that trees and shrubs could be planted. A series of on-site monitoring systems will allow Suncor to track the site. The total cost of the project was within expectations. In January 2010, Suncor began work in on the 440 hectare Pond 5 which was decommissioned in November 2009. To date, coke roadways have been established on Pond 5 to enable dewatering activities using wick drains. 2 figs.

  8. Pond Dynamics and Supraglacial-Englacial Connectivity on Debris-Covered Lirung Glacier, Nepal

    Directory of Open Access Journals (Sweden)

    Evan S. Miles

    2017-09-01

    Full Text Available The hydrological systems of heavily-downwasted debris-covered glaciers differ from those of clean-ice glaciers due to the hummocky surface and debris mantle of such glaciers, leading to a relatively limited understanding of drainage pathways. Supraglacial ponds represent sinks within the discontinuous supraglacial drainage system, and occasionally drain englacially. To assess pond dynamics, we made pond water level measurements on Lirung Glacier, Nepal, during May and October of 2013 and 2014. Simultaneously, aerial, satellite, and terrestrial orthoimages and digital elevation models were obtained, providing snapshots of the ponds and their surroundings. We performed a DEM-based analysis of the glacier's closed surface catchments to identify surface drainage pathways and englacial drainage points, and compared this to field observations of surface and near-surface water flow. The total ponded area was higher in the pre-monsoon than post-monsoon, with individual ponds filling and draining seasonally associated with the surface exposure of englacial conduit segments. We recorded four pond drainage events, all of which occurred gradually (duration of weeks, observed diurnal fluctuations indicative of varying water supply and outflow discharge, and we documented instances of interaction between distant ponds. The DEM drainage analysis identified numerous sinks >3 m in depth across the glacier surface, few of which exhibited ponds (23%, while the field survey highlighted instances of surface water only explicable via englacial routes. Taken together, our observations provide evidence for widespread supraglacial-englacial connectivity of meltwater drainage paths. Results suggest that successive englacial conduit collapse events, themselves likely driven by supraglacial pond drainage, cause the glacier surface drainage system to evolve into a configuration following relict englacial conduit systems. Within this system, ponds form in depressions of

  9. Perched Lava Pond Complex on South Rift of Axial Volcano Revealed in AUV Mapping

    Science.gov (United States)

    Paduan, J. B.; Clague, D. A.; Caress, D. W.; Thomas, H. J.

    2013-12-01

    An extraordinary lava pond complex is located on Axial Volcano's distal south rift. It was discovered in EM300 multibeam bathymetry collected in 1998, and explored and sampled with ROVs Tiburon in 2005 and Doc Ricketts in 2013. It was surveyed with the MBARI Mapping AUV D. Allan B. in 2011, in a complicated mission first flying above the levees at constant depth, then skimming ~5 m over the levees at a different constant depth to survey the floors, then twice switching to constant altitude mode to map outside the ponds. The AUV navigation was adjusted using the MB-System tool mbnavadjust so that bathymetric features match in overlapping and crossing swaths. The ~1-m resolution AUV bathymetry reveals extremely rough terrain, where low-resolution EM300 data had averaged acoustic returns and obscured details of walls, floors, a breach and surrounding flows, and gives context to the ROV observations and samples. The 6 x 1.5 km pond complex has 4 large and several smaller drained ponds with rims 67 to 106 m above the floors. The combined volume before draining was 0.56 km3. The ponds overflowed to build lobate-flow levees with elongate pillows draping outer flanks, then drained, leaving lava veneer on vertical inner walls. Levee rim depths vary by only 10 m and are deeper around the southern ponds. Deep collapse-pits in the levees suggest porosity of pond walls. The eastern levee of the northeastern pond breached, draining the interconnected ponds, and fed thick, rapidly-emplaced, sheet-flows along the complex's east side. These flows travelled at least 5.5 km down-rift and have 19-33 m deep drained ponds. They extended up-rift as well, forming a 10 x 2.5 km ponded flow with level 'bathtub rings' as high as 35 m above the floor marking that flow's high-stand. Despite the breach, at least 0.066 km3 of the molten interior of the large ponds also drained back down the eruptive fissures, as the pond floors are deeper than the sill and sea floor outside the complex. Tumulus

  10. Thermal evolutions of two kinds of melt pond with different salinity

    Science.gov (United States)

    Kim, Joo-Hong; Wilkinson, Jeremy; Moon, Woosok; Hwang, Byongjun; Granskog, Mats

    2016-04-01

    Melt ponds are water pools on sea ice. Their formation reduces ice surface albedo and alter surface energy balance, by which the ice melting and freezing processes are regulated. Thus, better understanding of their radiative characteristics has been vital to improve the simulation of melting/freezing of sea ice in numerical models. A melt pond would preserve nearly fresh water if it formed on multi-year ice and no flooding of sea water occurred, whereas a melt pond would contain more salty water if it formed on thinner and porous first-year ice, if there were an inflow of sea water by streams or cracks. One would expect that the fluid dynamic/thermodynamic properties (e.g., turbulence, stability, etc.) of pond water are influenced by the salinity, so that the response of pond water to any heat input (e.g., shortwave radiation) would be different. Therefore, better understanding of the salinity-dependent thermal evolution also has significant potential to improve the numerical simulation of the sea ice melting/freezing response to radiative thermal forcing. To observe and understand the salinity-dependent thermal evolution, two ice mass balance buoys (IMBs) were deployed in two kinds (fresh and salty) of melt pond on a same ice floe on 13 August 2015 during Araon Arctic cruise. The thermistor chain, extending from the air through the pond and ice into the sea water, was deployed through a drilled borehole inside the pond. Besides, the IMBs were also accompanied with three broadband solar radiation sensors (two (up and down) in the air over melt pond and one upward-looking under sea ice) to measure the net shortwave radiation at the pond surface and the penetrating solar radiation through ice. Also, the web camera was installed to observe any updates in the conditions of equipment and surrounding environment (e.g., weather, surface state, etc.). On the date of deployment, the fresh pond had salinity of 2.3 psu, light blue color, lots of slush ice particles which

  11. 复合人工湿地-池塘养殖生态系统细菌多样性研究%Bacterial Diversity Investigation on an Integrated System of Constructed Wetland and Pond Aquaculture

    Institute of Scientific and Technical Information of China (English)

    姚延丹; 李谷; 陶玲; 李晓莉; 张世羊; 赵巧玲; 林玉良

    2011-01-01

    The bacterial diversity investigation in the integrated system of constructed wetland and pond aquaculture was carried out during the period of Aug.-Oct. 2009, using analytic method of DGGE (denatured gradient gel electrophoresis). The findings presented that temperature and DO of the culture ponds changed over the investigation period, and both bacterial density and diversity in the culture pond varied with change of the season; in addition, the levels of NH4 and TP in the control pond were significantly higher (p<0.05) than those in the recirculation ponds. Correlation analysis pertaining to the investigation revealed that bacterial diversity was remarkably and positively correlated with DO, but negatively with NHJ and TP. It was concluded that the pond-recirculation aquaculture could enhance bacterial diversity in the ponds thus the pond system became more stable ecologically.%于2009年8至10月对比调查研究了由人工湿地-池塘养殖复合构成的池塘循环水养殖系统和传统池塘养殖系统中水体理化和生物特征,并利用变性梯度凝胶电泳技术(DGGE)分析了两系统中的细菌多样性。研究结果表明:试验期间各池塘水温和溶氧随月份呈下降趋势,对照塘NH4+-N和TP显著高于循环塘(P<0.05),而循环塘间无显著差异;各池塘细菌丰度和多样性指数均呈季节性变化,对照塘细菌丰度高于循环塘,且波动明显,而多样性指数却低于循环塘,细菌群落结构趋于简单;循环塘的细菌多样性指数逆水流方向呈增加趋势,P2塘较P4受循环水流的调控作用稍大。相关分析表明,细菌多样性指数与DO显著正相关,与NH4+-N、TP负相关。因此,池塘循环水养殖能够提高水体中细菌的生物多样性,相应池塘生态系统更具稳定性。

  12. Nitrogen Transformations and Removal Mechanisms in Algal and Duckweed Waste Stabilisation Ponds

    NARCIS (Netherlands)

    Zimmo, O.

    2003-01-01

    Effective treatment of nitrogen containing wastewater is required to prevent eutrophication and groundwater pollution. This thesis shows that effective treatment may be combined with substantial nitrogen recovery in duckweed-based waste stabilisation ponds. In these ponds nitrogen is absorbed by rap

  13. A computational study of salt diffusion and heat extraction in solar pond plants

    Energy Technology Data Exchange (ETDEWEB)

    Angeli, Celestino [Dipartimento di Chimica, Universita di Ferrara, Via Borsari 46, I-44100 Ferrara (Italy); Leonardi, Erminia [CRS4, Center for Advanced Studies, Research and Development in Sardinia, Parco Scientifico e Tecnologico, POLARIS, Edificio 1, 09010 Pula, CA (Italy); Maciocco, Luca [ADACAP, Advanced Acceleration Applications, Technoparc-rue Diesel 20, Fr-D1630 St. Genis Pouilly (France)

    2006-11-15

    The problem of the development of salt concentration profiles in a solar pond is investigated, the thermodiffusion contribution is also taken into account, using a one-dimensional mathematical model and a finite-difference approach. A novel scheme of heat extraction from the solar pond is presented, along with preliminary two-dimensional computational fluid dynamics (CFD) simulations. (author)

  14. REMOVAL OF HELMINTH PARASITIC EGGS FROM WASTE STABILIZATION PONDS AT SHIMOGA

    Directory of Open Access Journals (Sweden)

    M. SHANTHALA

    2007-01-01

    Full Text Available Helminth ova removal rates from waste stabilization pond effluents under tropical conditions ofShimoga using both laboratory and field modal ponds was undertaken. The helminthes were removedto the tune of 100% from laboratory model batch system ponds within 15 days of detention timeand it was only 65% in case of laboratory model continuos flow system ponds. The observation infield model ponds revealed an average 90% removal with 10 days retention time. A 100% removalcan not be expected both in continuous flow system laboratory model and field pond systems asthese receive daily fresh load of helminth eggs through influent sewage. The helminth ova are usallyremoved from waste stabilization ponds systems through sedimentation process. It is because thehelminth eggs attached to the suspended solids and when these solids settle to the bottom, the eggsare also removed from pelagic water. In the present study eggs of 4 helminth species viz. Ascarislumbricoides, Hymenolepis diminuta, Hymenolepis nana and Enterobius vermicularis wereencountered. Their rate of ova removal in batch system ponds was 99%, 97.4%, 94.9% and 98.8%for respective species. Presence of these ova in the sewage water indicates the prevalence of infectionin city population.

  15. How to maximally support local and regional biodiversity in applied conservation? Insights from pond management.

    Directory of Open Access Journals (Sweden)

    Pieter Lemmens

    Full Text Available Biodiversity and nature values in anthropogenic landscapes often depend on land use practices and management. Evaluations of the association between management and biodiversity remain, however, comparatively scarce, especially in aquatic systems. Furthermore, studies also tend to focus on a limited set of organism groups at the local scale, whereas a multi-group approach at the landscape scale is to be preferred. This study aims to investigate the effect of pond management on the diversity of multiple aquatic organism groups (e.g. phytoplankton, zooplankton, several groups of macro-invertebrates, submerged and emergent macrophytes at local and regional spatial scales. For this purpose, we performed a field study of 39 shallow man-made ponds representing five different management types. Our results indicate that fish stock management and periodic pond drainage are crucial drivers of pond biodiversity. Furthermore, this study provides insight in how the management of eutrophied ponds can contribute to aquatic biodiversity. A combination of regular draining of ponds with efforts to keep ponds free of fish seems to be highly beneficial for the biodiversity of many groups of aquatic organisms at local and regional scales. Regular draining combined with a stocking of fish at low biomass is also preferable to infrequent draining and lack of fish stock control. These insights are essential for the development of conservation programs that aim long-term maintenance of regional biodiversity in pond areas across Europe.

  16. Nitrogen transformations and removal mechanisms in algal and duckweed stabilisation ponds

    NARCIS (Netherlands)

    Zimmo, O.

    2003-01-01

    This thesis describes the results of a comparative study of the performance of algae-based ponds (ABPs) and duckweed-based ponds (DBPs) for wastewater treatment, with emphasis on nitrogen transformations and removal mechanisms.Batch experiments simulating algae and duckweed ( Lemna gibba )

  17. Nitrogen Transformations and Removal Mechanisms in Algal and Duckweed Waste Stabilisation Ponds

    NARCIS (Netherlands)

    Zimmo, O.

    2003-01-01

    Effective treatment of nitrogen containing wastewater is required to prevent eutrophication and groundwater pollution. This thesis shows that effective treatment may be combined with substantial nitrogen recovery in duckweed-based waste stabilisation ponds. In these ponds nitrogen is absorbed by

  18. Effect of daily minimum pond dissolved oxygen concentration on hybrid striped bass fingerling yield

    Science.gov (United States)

    Management of dissolved oxygen (DO) concentration in ponds at night during the growing season is important because fish growth and yield are greater in ponds with higher nightly DO concentrations. The purpose of this study was to quantify the production and water quality responses of hybrid striped ...

  19. The impact of cooling ponds in North Central Texas on dairy farm performance

    NARCIS (Netherlands)

    Tomaszewski, M.A.; Haan, de M.H.A.; Thompson, J.A.; Jordan, E.R.

    2005-01-01

    The objective of this study was to determine whether measurable differences existed between farms with and without cooling ponds. Data from Dairy Herd Improvement records for 1999 through 2002 were obtained on 42 herds located in North Central Texas. Nineteen herds had installed cooling ponds,

  20. 3D Modelling of Transport, Deposition and Resuspension of Highway Deposited Sediments in wet Detention Ponds

    DEFF Research Database (Denmark)

    Bentzen, Thomas Ruby

    2010-01-01

    The paper presents results from an experimental and numerical study of flows and transport of primarily particle bound pollutants in highway wet detention ponds. The study presented here is part of a general investigation on road runoff and pollution in respect to wet detention ponds. The objecti...

  1. Distribution of trematodes in snails in ponds at integrated small-scale aquaculture farms

    NARCIS (Netherlands)

    Boerlage, A.S.; Graat, E.A.M.; Verreth, J.A.J.; Jong, de M.C.M.

    2013-01-01

    In integrated small-scale aquaculture farming, animal and human excreta maybe used as fish feed and pond fertilizer, thereby enhancing transmission of fish-borne zoonotic trematodes (FZTs) from final hosts, like humans, pigs and chickens, to snails. Areas within a pond could vary in trematode egg-lo

  2. On the addition of heat to solar pond from external sources

    NARCIS (Netherlands)

    Ganguly, S.; Jain, Ravi; Date, Abhijit; Akbarzadeh, Aliakbar

    2017-01-01

    This brief note addresses the method of adding heat to a solar pond from an external source which is used to enhance the performance of a solar pond. Heat energy collected by Evacuated Tube Solar Collectors (ETSC) is transferred by circulating fluid from the Lower Convective Zone (LCZ) of a solar po

  3. Geo-engineering experiments in two urban ponds to control eutrophication

    NARCIS (Netherlands)

    Waajen, G.; van Oosterhout, F.; Douglas, G.; Lurling, M.

    2016-01-01

    Many urban ponds experience detrimental algal blooms as the result of eutrophication. During a two year field experiment, the efficacy of five in situ treatments to mitigate eutrophication effects in urban ponds was studied. The treatments targeted the sediment phosphorus release and were intended t

  4. A model to estimate hydrological processes and water budget in an irrigation farm pond

    Science.gov (United States)

    Ying Ouyang; Joel O. Paz; Gary Feng; John J. Read; Ardeshir Adeli; Johnie N. Jenkins

    2017-01-01

    With increased interest to conserve groundwater resources without reducing crop yield potential, more on-farm water storage ponds have been constructed in recent years in USA and around the world. However, the hydrological processes, water budget, and environmental benefits and consequences of these ponds have not yet been fully quantified. This study developed a...

  5. Massive subsurface ice formed by refreezing of ice-shelf melt ponds

    NARCIS (Netherlands)

    Hubbard, Bryn; Luckman, A.; Ashmore, David; Bevan, S.; Kulessa, Bernd; Kuipers Munneke, P.|info:eu-repo/dai/nl/304831891; phillipe, morgane; Jansen, Daniela; Booth, Adam; Sevestre, Heidi; Tison, Jean-Louis; O'Leary, Martin; Rutt, Ian

    2016-01-01

    Surface melt ponds form intermittently on several Antarctic ice shelves. Although implicated in ice-shelf break up, the consequences of such ponding for ice formation and ice-shelf structure have not been evaluated. Here we report the discovery of a massive subsurface ice layer, at least 16 km acros

  6. Modeling phosphorus removal in wet ponds with filter zones containing sand or crushed concrete

    DEFF Research Database (Denmark)

    Sønderup, Melanie J.; Egemose, Sara; Hoffmann, Carl Christian;

    2014-01-01

    Abstract Generally, wet ponds are constructed only to reduce the hydraulic load of downstream receiving water bodies. Often most particulate matter will be retained, whereas dissolved nutrients mostly will be unaffected by the pond due to short retention times. A suite of lab-experiments have dem...

  7. Modeling phosphorus removal in wet ponds with filter zones containing sand or crushed concrete

    DEFF Research Database (Denmark)

    Sønderup, Melanie J.; Egemose, Sara; Hoffmann, Carl Christian

    2014-01-01

    Abstract Generally, wet ponds are constructed only to reduce the hydraulic load of downstream receiving water bodies. Often most particulate matter will be retained, whereas dissolved nutrients mostly will be unaffected by the pond due to short retention times. A suite of lab-experiments have dem...

  8. 78 FR 59731 - License Amendment Request for Closure of Calcium Fluoride Ponds at Honeywell Metropolis Works...

    Science.gov (United States)

    2013-09-27

    ... From the Federal Register Online via the Government Publishing Office NUCLEAR REGULATORY COMMISSION License Amendment Request for Closure of Calcium Fluoride Ponds at Honeywell Metropolis Works... fluoride ponds in-place, by stabilization of the contents and construction of a cover system over the...

  9. Variants of Microcystin in Southeastern USA Channel Catfish (Ictalurus puntctatus ralfinesque) Production Ponds

    Science.gov (United States)

    A synoptic survey of 486 channel catfish production ponds was made from the southern states (AL, AR, LA, MS) that produce over 90% of commercially grown fish. The survey assessed distribution of microcystin toxins in these ponds. A total of 12 variants of microcystin were detected. The threshold ...

  10. On the addition of heat to solar pond from external sources

    NARCIS (Netherlands)

    Ganguly, S.; Jain, Ravi; Date, Abhijit; Akbarzadeh, Aliakbar

    2017-01-01

    This brief note addresses the method of adding heat to a solar pond from an external source which is used to enhance the performance of a solar pond. Heat energy collected by Evacuated Tube Solar Collectors (ETSC) is transferred by circulating fluid from the Lower Convective Zone (LCZ) of a solar

  11. Trace gas exchanges of marsh-pond-marsh constructed wetlands treating swine wastewater

    Science.gov (United States)

    Marsh-pond-marsh (MPM) constructed wetlands have been used effectively to treat wastewater from swine anaerobic lagoons. However, at high N loading rates, a significant portion of ammonia in the wastewater could be volatilized into the atmosphere. To mitigate ammonia emission, ponds can be covered w...

  12. Microbial Contamination of Community Pond Water in Dibrugarh District of Assam

    Directory of Open Access Journals (Sweden)

    Purnima Gogoi

    2013-04-01

    Full Text Available Our drinking water today, far from being pure, contains bacteria, viruses, inorganic minerals and a chemical cocktail that is unsuitable for human consumption. A study was undertaken with the objectives of evaluating the viable coliforms along with other water born bacteria in pond water environment. Water samples were collected from three community ponds of Dibrugarh district which are used mostly for bathing, watering livestock as well as drinking under water crises condition. Bacteria from collected pond samples were isolated by dilution plate technique. Coliform group in water was evaluated with the reference to EPA manual Microbiology Methods. The results showed that of the three ponds, pond 1 has highest number of bacterial counts (30x10 4 followed by pond 3 (24 x10 4 whereas pond 2 showed minimum colony count (12 x 10 3 per ml of water. The coliform bacteria count in the above pond water sample is far above the safety limit of WHO. Besides gram negative rod shaped coliform group, two groups of gram positive round shaped (with colony colour violet and orange and gram positive rod shaped bacteria group were also found dominant.

  13. Macroinvertebrate biodiversity patterns during primary succession in manmade ponds in north-eastern Spain

    Directory of Open Access Journals (Sweden)

    Leticia Miguel-Chinchilla

    2014-03-01

    Full Text Available The main aim of this work was to evaluate the primary succession of manmade ponds by studying the temporal patterns of the pond biodiversity metrics. We surveyed the macroinvertebrate community, the water and the sediment of 19 manmade ponds of different ages (from 1 to 22 years located at reclaimed opencast coal mines in northeastern Spain. This study showed an increase of biodiversity with pond age: the oldest ponds showed higher complexity and more rare taxa than the youngest ponds, while the taxonomic richness did not change. These results highlighted the need for using a wide range of biodiversity metrics. Moreover, our results suggest that post-mining landscapes could be limiting environments for the evolving macroinvertebrate community because pond age explained less of the biodiversity variance than the environmental characteristics. The changes found in water and sediment during this time were not reflected in changes in biodiversity, and the levels of biodiversity in our study area were lower than those of restored or manmade ponds of similar ages.

  14. Nitrogen transformations and removal mechanisms in algal and duckweed stabilisation ponds

    NARCIS (Netherlands)

    Zimmo, O.

    2003-01-01

    This thesis describes the results of a comparative study of the performance of algae-based ponds (ABPs) and duckweed-based ponds (DBPs) for wastewater treatment, with emphasis on nitrogen transformations and removal mechanisms.Batch experiments simulating algae and duckweed ( Lemna gibba ) stabilisa

  15. Effect of carbon dioxide and ammonium removal on pH changes in polishing ponds

    NARCIS (Netherlands)

    Cavalcanti, P.F.F.; Haandel, van A.; Lettinga, G.

    2002-01-01

    If nutrient removal is to be obtained in ponds treating sewage, the pH must be raised so that ammonia can desorb and phosphates can precipitate. In this paper it is shown that the pH increase in ponds can be predicted quantitatively from simple stoichiometry, taking into consideration physical and b

  16. Massive subsurface ice formed by refreezing of ice-shelf melt ponds

    NARCIS (Netherlands)

    Hubbard, Bryn; Luckman, A.; Ashmore, David; Bevan, S.; Kulessa, Bernd; Kuipers Munneke, P.; phillipe, morgane; Jansen, Daniela; Booth, Adam; Sevestre, Heidi; Tison, Jean-Louis; O'Leary, Martin; Rutt, Ian

    2016-01-01

    Surface melt ponds form intermittently on several Antarctic ice shelves. Although implicated in ice-shelf break up, the consequences of such ponding for ice formation and ice-shelf structure have not been evaluated. Here we report the discovery of a massive subsurface ice layer, at least 16 km acros

  17. An Instructional Design Using the Virtual Ecological Pond for Science Education in Elementary Schools

    Science.gov (United States)

    Tarng, Wernhuar; Ou, Kuo-Liang; Tsai, Wen-Shin; Lin, Yu-Si; Hsu, Chen-Kai

    2010-01-01

    Ecological ponds can be a good teaching tool for science teachers, but they must be built and maintained properly to provide students with a safe and suitable learning environment. However, many schools do not have the ability to build and maintain an ecological pond. This study used virtual reality technology to develop a web-based virtual…

  18. An Instructional Design Using the Virtual Ecological Pond for Science Education in Elementary Schools

    Science.gov (United States)

    Tarng, Wernhuar; Ou, Kuo-Liang; Tsai, Wen-Shin; Lin, Yu-Si; Hsu, Chen-Kai

    2010-01-01

    Ecological ponds can be a good teaching tool for science teachers, but they must be built and maintained properly to provide students with a safe and suitable learning environment. However, many schools do not have the ability to build and maintain an ecological pond. This study used virtual reality technology to develop a web-based virtual…

  19. Mechanisms and implications of α-HCH enrichment in melt pond water on Arctic sea ice.

    Science.gov (United States)

    Pućko, M; Stern, G A; Barber, D G; Macdonald, R W; Warner, K-A; Fuchs, C

    2012-11-06

    During the summer of 2009, we sampled 14 partially refrozen melt ponds and the top 1 m of old ice in the pond vicinity for α-hexachlorocyclohexane (α-HCH) concentrations and enantiomer fractions (EFs) in the Beaufort Sea. α-HCH concentrations were 3 - 9 times higher in melt ponds than in the old ice. We identify two routes of α-HCH enrichment in the ice over the summer. First, atmospheric gas deposition results in an increase of α-HCH concentration from 0.07 ± 0.02 ng/L (old ice) to 0.34 ± 0.08 ng/L, or ~20% less than the atmosphere-water equilibrium partitioning concentration (0.43 ng/L). Second, late-season ice permeability and/or complete ice thawing at the bottom of ponds permit α-HCH rich seawater (~0.88 ng/L) to replenish pond water, bringing concentrations up to 0.75 ± 0.06 ng/L. α-HCH pond enrichment may lead to substantial concentration patchiness in old ice floes, and changed exposures to biota as the surface meltwater eventually reaches the ocean through various drainage mechanisms. Melt pond concentrations of α-HCH were relatively high prior to the late 1980-s, with a Melt pond Enrichment Factor >1 (MEF; a ratio of concentration in surface meltwater to surface seawater), providing for the potential of increased biological exposures.

  20. Massive subsurface ice formed by refreezing of ice-shelf melt ponds

    NARCIS (Netherlands)

    Hubbard, Bryn; Luckman, A.; Ashmore, David; Bevan, S.; Kulessa, Bernd; Kuipers Munneke, P.; phillipe, morgane; Jansen, Daniela; Booth, Adam; Sevestre, Heidi; Tison, Jean-Louis; O'Leary, Martin; Rutt, Ian

    2016-01-01

    Surface melt ponds form intermittently on several Antarctic ice shelves. Although implicated in ice-shelf break up, the consequences of such ponding for ice formation and ice-shelf structure have not been evaluated. Here we report the discovery of a massive subsurface ice layer, at least 16 km