Science.gov

Sample records for 216-b-3 pond system

  1. 216-B-3 expansion ponds closure plan

    SciTech Connect

    Not Available

    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.

  2. Ground water impact assessment report for the 216-B-3 Pond system

    SciTech Connect

    Johnson, V.G.; Law, A.G.; Reidel, S.P.; Evelo, S.D.; Barnett, D.B.; Sweeney, M.D.

    1995-01-01

    Ground water impact assessments were required for a number of liquid effluent receiving sites according to the Hanford Federal Facility Agreement and Consent Order Milestones M-17-00A and M-17-00B, as agreed upon by the US Department of Energy. This report is one of the last three assessments required and addresses the impact of continued discharge of uncontaminated wastewater to the 216-B-3C expansion lobe of the B Pond system in the 200 East Area until June 1997. Evaluation of past and projected effluent volumes and composition, geohydrology of the receiving site, and contaminant plume distribution patterns, combined with ground water modeling, were used to assess both changes in ground water flow regime and contaminant-related impacts.

  3. State Environmental Policy Act (SEPA) environmental checklist form for the closure of the 216-B-3 Pond System

    SciTech Connect

    Not Available

    1990-03-30

    This document describes the activities for partial closure of the 216-B-3 Pond System operated by the US Department of Energy-Richland Operations Office and co-operated by the Westinghouse Hanford Company. The Hanford site has been divided into operable units to facilitate cleanup under CERCLA, the State of Washington Hazardous Waste Management Act of 1976, and RCRA corrective action provisions. An operable unit is a grouping of individual waste management units based primarily on geographic area, common waste sources, and similar geohydrologic properties. The Hanford Site waste management units have been categorized into past-practice units and TSD units. A past-practice unit is a waste management unit where waste has been disposed and is not subject to regulation as a TSD unit. All waste management units, including TSD units within an operable unit, generally will undergo investigation and remediation (closure) at the same time. 85 refs., 50 figs., 25 tabs.

  4. The installation of the Westbay multiport ground-water sampling system in well 699-43-42K near the 216-B-3 pond

    SciTech Connect

    Gilmore, T.J.

    1989-09-01

    In 1988 and 1989, Pacific Northwest Laboratory installed a multiport ground-water sampling system in well 699-43-42K drilled near the 216-B-3 Pond on the Hanford Site in southeastern Washington state. The multiport system will be used to evaluate methods for determining the vertical distribution of contaminants and hydraulic heads in ground water. This installation was in conjunction with a similar multiport installation near the 300 Area of the Hanford Site. Well 699-43-42K is adjacent to two Resource Conservation and Recovery Act (RCRA) ground-water monitoring wells, which will allow for a comparison of sampling intervals and head measurements between the multiport system and the RCRA monitoring wells. Eight sampling ports were installed in the upper unconfined aquifer by backfilling at depths of 161.1 ft, 174.1 ft, 187.1 ft, 201.17 ft, 217.2 ft, 230.2 ft, 243.2 ft, and 255.2 ft below land surface. However, because of damage to the casing during installation, only the top four ports should be used for pressure measurements and sampling until repairs occur. The locations of the sampling ports were determined by the hydrogeology of the area and the screened intervals of adjacent ground-water monitoring wells. 4 refs., 8 figs.

  5. State Environmental Policy Act (SEPA) Environmental Checklist Form 216-B-3 Expansion Ponds Closure Plan. Revision 1

    SciTech Connect

    Not Available

    1993-12-01

    The 216-B-3 Expansion Ponds Closure Plan (Revision 1) consists of a Part A Dangerous Waste Permit Application and a Resource Conservation and Recovery Act Closure Plan. An explanation of the Part A submitted with this document is provided at the beginning of the Part A Section. The closure plan consists of nine chapters and five appendices. The 216-B-3 Pond System consists of a series of four earthen, unlined, interconnected ponds and the 216-B-3-3 Ditch that receive waste water from various 200 East Area operating facilities. These four ponds, collectively. Waste water (primarily cooling water, steam condensate, and sanitary water) from various 200 East Area facilities is discharged to the 216-B-3-3 Ditch. Water discharged to the 216-8-3-3 Ditch flows directly into the 216-B-3 Pond. In the past, waste water discharges to B Pond and the 216-B-3-3 Ditch 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 nonradioactive dangerous portion of mixed waste is regulated under RCRA. Mixed waste also may be considered a hazardous substance under the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA) when considering remediation of waste sites.

  6. Groundwater monitoring plan for the Hanford Site 216-B-3 pond RCRA facility

    SciTech Connect

    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.

  7. Groundwater Monitoring Plan for the Hanford Site 216-B-3 Pond RCRA Facility

    SciTech Connect

    Barnett, D. Brent; Smith, Ronald M.; Chou, Charissa J.

    2000-11-28

    The 216-B-3 Pond was a series of ponds for disposal of liquid effluent from past Hanford production facilities. In 1990, groundwater monitoring at B Pond was elevated from "detection" to assessment status because total organic halides and total organic carbon were found to exceed critical means in two wells. Groundwater quality assessment, which ended in 1996, failed to find any specific hazardous waste contaminant that could have accounted for the isolated occurrences of elevated total organic halides and total organic carbon. Hence, the facility was subsequently returned to detection-level monitoring in 1998. Exhaustive groundwater analyses during the assessment period indicated that only two contaminants, tritium and nitrate, could be positively attributed to the B Pond System, with two others (arsenic and I-129) possibly originating from B Pond. Chemical and radiological analyses of soil at the main pond and 216-B-3-3 ditch has not revealed significant contamination. Based on the observed, minor contamination in groundwater and in the soil column, three parameters were selected for site-specific, semiannual monitoring; gross alpha, gross beta, and specific conductance. Total organic halides and total organic carbon are included as constituents because of regulatory requirements. Nitrate, tritium, arsenic, and iodine-129 will be monitored under the aegis of Hanford site-wide monitoring. Although the B Pond System is not scheduled to advance from RCRA interim status to final status until the year 2003, a contingency plan for an improved monitoring strategy, which will partially emulate final status requirements, will be contemplated before the official change to final status. This modification will allow a more sensible and effective screening of groundwater for the facility.

  8. Groundwater Monitoring Plan for the Hanford Site 216-B-3 Pond RCRA Facility

    SciTech Connect

    Barnett, D BRENT.; Smith, Ronald M.; Chou, Charissa J.; McDonald, John P.

    2005-11-01

    The 216-B-3 Pond system was a series of ponds used for disposal of liquid effluent from past Hanford production facilities. In operation from 1945 to 1997, the B Pond System has been a Resource Conservation and Recovery Act (RCRA) facility since 1986, with RCRA interim-status groundwater monitoring in place since 1988. In 1994 the expansion ponds of the facility were clean closed, leaving only the main pond and a portion of the 216-B-3-3 ditch as the currently regulated facility. In 2001, the Washington State Department of Ecology (Ecology) issued a letter providing guidance for a two-year, trial evaluation of an alternate, intrawell statistical approach to contaminant detection monitoring at the B Pond system. This temporary variance was allowed because the standard indicator-parameters evaluation (pH, specific conductance, total organic carbon, and total organic halides) and accompanying interim status statistical approach is ineffective for detecting potential B-Pond-derived contaminants in groundwater, primarily because this method fails to account for variability in the background data and because B Pond leachate is not expected to affect the indicator parameters. In July 2003, the final samples were collected for the two-year variance period. An evaluation of the results of the alternate statistical approach is currently in progress. While Ecology evaluates the efficacy of the alternate approach (and/or until B Pond is incorporated into the Hanford Facility RCRA Permit), the B Pond system will return to contamination-indicator detection monitoring. Total organic carbon and total organic halides were added to the constituent list beginning with the January 2004 samples. Under this plan, the following wells will be monitored for B Pond: 699-42-42B, 699-43-44, 699-43-45, and 699-44-39B. The wells will be sampled semi-annually for the contamination indicator parameters (pH, specific conductance, total organic carbon, and total organic halides) and annually for

  9. Partitioned pond aquaculture systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    World aquaculture is dominated by the use of simple earthen ponds in which suitable water quality is maintained by photosynthetic processes. Relying upon sunlight to maintain water quality offers the lowest cost and most sustainable approach to fish or shellfish production, which explains the popula...

  10. Chemical treatment costs reduced with in-pond raceway systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Production systems such as in-pond raceway systems (IPRS) and split ponds are providing an alternative to traditional pond culture for raising catfish in several southeastern states. One advantage noted by farmers utilizing these systems is the reduced cost associated with the chemical treatment of ...

  11. Chemical treatment costs reduced with use of in-pond raceway systems compared to traditional pond aquaculture

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Production systems such as in-pond raceway systems (IPRS) and split ponds are providing an alternative to traditional pond culture for raising catfish in several southeastern states. One advantage noted by farmers utilizing these systems is the reduced cost associated with the chemical treatment of ...

  12. Truscott Brine Lake solar-pond system conceptual design

    SciTech Connect

    Leboeuf, C.M.; May, E.K.

    1982-08-01

    Discussed is a conceptual design study for a system of electricity-producing salt-gradient solar ponds that will provide power to a chloride control project under construction near Truscott, Tex. The chloride control project comprises a 1200-ha (3000-acre) brine impoundment lake to which brine will be pumped from several salty sources in the Wichita River basin. The solar ponds are formed by natural evaporation of the briny water pumped to Truscott. Heat is extracted from the solar ponds and used to drive organic Rankine-cycle (ORC) generators. Ponds were sized to provide the pumping needs of the chloride control project and the maintenance requirements of the solar ponds. The system includes six solar pond modules for a total area of 63.1 ha, and produces 1290 kW of base load electricity. Although sized for continuous power production, alternative operating scenarios involving production of peak power for shorter durations were also examined.

  13. Comparison of phytoplankton communities in catfish split-pond aquaculture systems with conventional ponds.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    There has been a growing interest and use of variations of partitioned aquaculture systems (PAS) in recent years by the southeastern United States of America farmed catfish industry. Split-pond systems, one type of PAS, are designed to better manage fish waste byproducts (e.g., ammonia) and dissolv...

  14. Nitrogen removal in recirculated duckweed ponds system.

    PubMed

    Benjawan, L; Koottatep, T

    2007-01-01

    Duckweed-based ponds (DWBPs) have the potential for nitrogen (N) removal from wastewater; however, operational problems such as duckweed die-off regularly occur. In this study, effluent recirculation was applied to the DWBPs to solve the above problem as well as to investigate N removal mechanisms. Two pilot scale recirculated DWBPs were employed to treat municipal wastewater. The average removal efficiencies for TN, TKN and NH4-N were 75%, 89% and 92%, respectively at TN loading of 1.3 g/m2.d and were 73%, 74% and 76%, respectively at TN loading of 3.3 g/m2.d. The effluent of the system under both operational conditions had stable quality and met the effluent standard. Duckweed die-off was not observed during the study, which proves the system stability and effluent recirculation which is thought to be a reason. N-mass balance revealed that nitrification-denitrification and duckweed uptake play major roles in these recirculated DWBPs. The rates of nitrification-denitrification were increased as TN loading was higher, which might be an influence from an abundance of N and a suitable condition. The rates of N uptake by duckweed were found similar and did not depend on the higher TN loading applied, as the duckweed has limited capacity to assimilate it. PMID:17591202

  15. A review of virus removal in wastewater treatment pond systems.

    PubMed

    Verbyla, Matthew E; Mihelcic, James R

    2015-03-15

    Wastewater treatment ponds (lagoons) are one of the most common types of technologies used for wastewater management worldwide, especially in small cities and towns. They are particularly well-suited for systems where the effluent is reused for irrigation. However, the efficiency of virus removal in wastewater treatment pond systems is not very well understood. The main objective of this paper is to critically review the major findings related to virus removal in wastewater treatment pond systems and to statistically analyze results reported in the literature from field studies on virus removal in these systems. A comprehensive analysis of virus removal reported in the literature from 71 different wastewater treatment pond systems reveals only a weak to moderate correlation of virus removal with theoretical hydraulic retention time. On average, one log10 reduction of viruses was achieved for every 14.5-20.9 days of retention, but the 95th percentile value of the data analyzed was 54 days. The mechanisms responsible for virus removal in wastewater treatment ponds were also reviewed. One recent finding is that sedimentation may not be a significant virus removal mechanism in some wastewater ponds. Recent research has also revealed that direct and indirect sunlight-mediated mechanisms are not only dependent on pond water chemistry and optics, but also on the characteristics of the virus and its genome. MS2 coliphage is considered to be the best surrogate for studying sunlight disinfection in ponds. The interaction of viruses with particles, with other microorganisms, and with macroinvertebrates in wastewater treatment ponds has not been extensively studied. It is also unclear whether virus internalization by higher trophic-level organisms has a protective or a detrimental effect on virus viability and transport in pond systems. Similarly, the impact of virus-particle associations on sunlight disinfection in ponds is not well understood. Future research should focus on

  16. Catfish disease cases in in-pond receway systems in Alabama: 2008-2013

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Production systems such as in-pond raceway systems (IPRS) and split-pond production systems are providing an alternative to traditional pond culture for raising catfish. Currently, there are over 1,300 water acres of production in Mississippi, Arkansas, and Alabama utilizing split-pond production sy...

  17. Catfish disease cases in in-pond raceway systems in Alabama: 2008-2013

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Production systems such as in-pond raceway systems (IPRS) and split-pond aquaculture systems are providing an alternative to traditional pond culture for raising catfish. Currently, there are over 1,300 water acres of production in Mississippi, Arkansas, and Alabama utilizing split-pond production s...

  18. In-pond raceway systems and catfish disease related cases in west Alabama

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Production systems such as in-pond raceway systems (IPRS) and split-pond production systems are providing an alternative to traditional pond culture for raising catfish. Currently, there are over 1,300 water acres of production in Mississippi, Arkansas, and Alabama utilizing split-pond production sy...

  19. Effectiveness of an urban runoff detention pond - Wetlands system

    USGS Publications Warehouse

    Martin, E.H.

    1988-01-01

    The effectiveness of an urban detention system, composed of a detention pond and wetlands in series, in reducing constituent loads carried in runoff was determined. The detention pond was effective in reducing loads of suspended solids and suspended metals. Suspended-phase efficiencies for solids, lead, and zinc ranged between 42 and 66%. Nutrient efficiencies were variable, ranging for all species and phases, from less than 0 to 72%. The wetlands generally was effective in reducing both suspended and dissolved loads of solids and metals. Total (dissolved + suspended) solids, lead, and zinc efficiencies ranged between 41 and 73%. Efficiencies for total nitrogen and phosphorus were 21 and 17%, respectively. The system, by combining the treatment of the pond of wetlands, was very effective in reducing loads of most constituents. Total solids, lead, and zinc efficiencies ranged between 55 and 83%. Total nitrogen and phosphorus efficiencies were 36 and 43%, respectively.The effectiveness of an urban detention system, composed of a detention pond and wetlands in series, in reducing constituent loads carried in runoff was determined. The detention pond was effective in reducing loads of suspended solids and suspended metals. Nutrient efficiencies were variable, ranging for all species and phases, from less than 0 to 72 percent. The wetlands generally was effective in reducing both suspended and dissolved loads of solids and metals. The system, by combining the treatment of the pond and wetlands, was very effective in reducing loads of most constituents.

  20. Truscott brine lake solar pond system conceptual design

    SciTech Connect

    Leboeuf, C.M.

    1982-01-01

    This paper discusses a conceptual design study for a system of electricity-producing salt-gradient solar ponds that will provide power to a chloride control project under construction by the Army Corps of Engineers near Truscott, Tex. The chloride control project comprises a 1200-ha (3000-acre) brine impoundment lake to which brine will be pumped from several salty sources in the Wichita River basin. The solar ponds are formed by natural evaporation of the briny water pumped to Truscott. Heat is extracted from the solar ponds and used to drive organic Rankine-cycle (ORC) generators. Ponds were sized to provide the pumping needs of the chloride control project and the maintenance requirements of the solar ponds. The system includes six solar pond modules for a total area of 63.1 ha, and produces 1290 kW of base load electricity. Although sized for continuous power production, alternative operating scenarios involving production of peak power for shorter durations were also examined.

  1. Catfish production guidelines for in-pond raceway systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fish have been cultured in raceways for over 150 years in the United States. Most of these raceways have been flow-through systems for production of cold water species such as rainbow trout (Oncorhynchus mykiss), although many other species have been produced. The development of In-Pond Raceways Sys...

  2. Sediment management in sustainable urban drainage system ponds.

    PubMed

    Heal, K V; Hepburn, D A; Lunn, R J

    2006-01-01

    Since removal and disposal of sustainable urban drainage system (SUDS) sediment can incur high maintenance costs, assessments of sediment volumes, quality and frequency of removal are required. Sediment depth and quality were surveyed annually from 1999-2003 in three ponds and one wetland in Dunfermline, Scotland, UK. Highest sediment accumulation occurred in Halbeath Pond, in the most developed watershed and with no surface water management train. From comparison of measured potentially toxic metal concentrations (Cd, Cr, Cu, Fe, Ni, Pb, Zn) with standards, the average sediment quality should not impair aquatic ecosystems. 72-84% of the metal flux into the SUDS was estimated to be associated with coarse sediment (> 500 microm diameter) suggesting that management of coarse sediment is particularly important at this site. The timing of sediment removal for these SUDS is expected to be determined by loss of storage volume, rather than by accumulation of contaminants. If sediment removal occurs when 25% of the SUDS storage volume has infilled, it would be required after 17 years in Halbeath Pond, but only after 98 years in Linburn Pond (which has upstream detention basins). From the quality measurements, sediment disposal should be acceptable on adjacent land within the boundaries of the SUDS studied. PMID:16838706

  3. Pumping performance of a slow-rotating paddlewheel for split-pond aquaculture systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Commercial catfish farmers are intensifying production by retrofitting ponds with variations of the partitioned aquaculture system (PAS). The split-pond system is the most common variation used commercially. The split-pond consists of a small fish-holding basin connected to a waste treatment lagoon ...

  4. A commercial-scale in-pond raceway system for ictalurid catfish production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A commercial-scale, in-pond raceway system was constructed in 2007 on a commercial catfish fish farm in west Alabama. The in-pond raceway system was installed in a 2.43-ha earthen pond with an average depth of 1.67 m. A slow-rotating paddlewheel (1.17 revolutions per minute) installed in each rac...

  5. A solar pond driven distillation and power production system

    NASA Astrophysics Data System (ADS)

    Johnson, D. H.; Leboeuf, C. M.; Waddington, D.

    In this paper a solar pond driven distillation and power production system is described. The storage layer of the solar pond serves as the holding tank for the concentrated brine effluent from the distillation process as well as the collector and storage medium for solar energy used to heat incoming salty river water. Steam from the distillation process expands through a turbine/generator combination to provide power for the water circulation and vacuum pumps of the system. Water from the surface mixed layer of the pond is used to condense the steam. The closely integrated distillation and power production system converts an incoming stream of brackish or saline water into an outlet stream of the required purity. Salt and power are also products of the system. A thermodynamic analysis of the energy and mass balances of the system has been performed and a performance model of the system has been developed. This has been used to size the system for the application of desalting saline tributaries of the Colorado River.

  6. Solar pond-driven distillation and power production system

    SciTech Connect

    Johnson, D.H.; Leboeuf, C.M.; Waddington, D.

    1981-12-01

    A solar pond-driven distillation and power production system is described. The storage layer of the solar pond serves as the holding tank for the concentrated brine effluent from the distillation process as well as the collector and storage medium for solar energy used to heat incoming salty river water. Steam from the distillation process expands through a turbine/generator combination to provide power for the water circulation and vacuum pumps of the system. Water from the surface mixed layer of the pond is used to condense the steam. The closely integrated distillation and power production system converts an incoming stream of brackish or saline water into an outlet stream of the required purity. Salt and power are also products of the system. A thermodyanamic analysis of the energy and mass balances of the system has been performed and a performance model of the system has been developed. This model was used to compute the requirements for desalting several saline tributaries of the Colorado River.

  7. Solar pond-driven distillation and power production system

    NASA Astrophysics Data System (ADS)

    Johnson, D.; Leboeuf, C. M.; Waddington, D.

    1981-12-01

    A solar pond driven distillation and power production system is described. The storage layer of the solar pond serves as the holding tank for the concentrated brine effluent from the distillation process as well as the collector and storage medium for solar energy used to heat incoming salty river water. Steam from the distillation process expands through a turbine/generator combination to provide power for the water circulation and vacuum pumps of the system. Water from the surface mixed layer of the pond is used to condense the steam. The closely integrated distillation and power production system converts an incoming stream of brackish or saline water into an outlet stream of the required purity. Salt and power are also products of the system. A thermodynamic analysis of the energy and mass balances of the system was performed and a performance model of the system is developed. This model is used to compute the requirements for desalting several saline tributaries of the Colorado River.

  8. Pumping performance of a modified commercial paddlewheel aerator for split-pond aquaculture systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The split-pond aquaculture system consists of a small fish-holding basin connected to a waste-treatment lagoon by two conduits. Split ponds require large water volumes circulated between the two basins (10,000 to 20,000 gal/min for 5- to 10-ac ponds) to remove fish waste and provide oxygenated water...

  9. Physical and hydrodynamic characteristics of a dairy shed waste stabilisation pond system.

    PubMed

    Fyfe, J; Smalley, J; Hagare, D; Sivakumar, M

    2007-01-01

    Waste stabilization pond systems are widely used to treat animal wastes under highly variable hydraulic loading regimes. These systems have received limited research attention with regard to their hydrodynamic behaviour and the potential impact of shock hydraulic loading on their performance. In this study a two-stage dairy shed waste stabilisation pond system was topographically surveyed to determine the physical shape and the theoretical hydraulic retention time (HRT) of each pond, as well as the extent of sludge accumulation in the primary pond. The primary pond was then subjected to a series of drogue tracking runs whereby weighted floating survey targets with submerged 'sails' were tracked during their movement through the pond at times of peak flow in order to characterise the hydrodynamic behaviour of the pond. The full capacity volumes of the primary and secondary ponds were calculated to be 1285 m3 and 2391 m3, respectively. Sludge had been accumulating in the primary pond at a rate of 0.73 m3/d over a period of 2.4 years and this has reduced the active treatment volume of the pond to 657 m3. Based on mean outflow, the HRTs of the ponds were 40 d and 137 d, respectively. The drogue runs revealed a vortex-like mixing pattern within the pond with higher velocities around the perimeter of the pond between the inlet and outlet, and lower velocities in the centre of the pond. In-pond velocities seemed relatively high in comparison with those from other drogue studies of larger ponds and the surging inflow caused the formation of a flow 'jet' that potentially contributed to significant short-circuiting. The range of influence of this flow jet, however, was limited to within 15 m of the inlet, suggesting that short-circuiting would be likely to occur only under certain high inflow conditions. PMID:17591191

  10. Uranium studies in the Tims Branch and Steed Pond system

    SciTech Connect

    Hayes, D.W.

    1984-11-01

    During the weekend of September 2--3, 1984, a part of the wooden spillway for Steed Pond gave way and the pond slowly drained. Consideration is being given to leaving Steed Pond dry. Steed Pond has accumulated some of the uranium discharged from 300 Area operations and past surveys have shown that the uranium concentration in the sediments ranges between 20 and 531 pCi/gm. The recently completed aerial survey of the exposed area of Steed Pond showed that the uranium was widely spread in the sediments of Steed Pond. Until ground cover is established over the exposed pond sediments, they will be subject to erosion. As much as 90 tons of sediment could be eroded from the exposed sediments in Steed Pond the first year, but the erosion could be reduced to 5--15 tons by establishing a ground cover such as rye grass. Only about 40% of the eroded sediment would be delivered to Upper Three Runs Creek, because most of the eroded sediment deposited before it reaches Upper Three Runs Creek. Less than 20 mCi of uranium would be transported downstream the first year from erosion of Steed Pond sediments, and this could be reduced to 2-- 5 mCi/year if ground cover is established.

  11. Examining Water Quality Variations of Tidal Pond System

    NASA Astrophysics Data System (ADS)

    Chui, T. F. M.; Cui, W.

    2014-12-01

    Brackish tidal shrimp ponds, traditionally referred to as gei wais, have been constructed along coastal areas in many parts of the world. The regular exchange of pond water with the surrounding coastal environment is important as it brings shrimp larvae and nutrients, etc. into and out of the pond. Such a water exchange can reduce the quality of the receiving waters; though there are opposing views recently because farming practices are becoming more sustainable while other sources of pollutions in the surroundings are increasing. This project monitors the water quality of a tidal shrimp pond and its receiving water at high temporal resolution. The pond is located within the wetland complex of Mai Po Nature Reserve in Hong Kong, China. Water quality parameters (i.e., dissolved oxygen, temperature, salinity, pH, water depth and chlorophyll) were recorded at 15-minute interval from December 2013 to March 2014 within the pond and also at its receiving water which is a water channel within a mangrove forest. Data reveals both daily and fortnightly fluctuations. Daily variations in mangrove correspond to both tidal flushing and insolation, whereas those within the pond correspond mainly to insolation. For example, dissolved oxygen in mangrove shows two peaks daily which correlate with tidal elevation, and that within the pond shows only one peak which correlates with sunlight. Dissolved oxygen within the pond also shows a fortnightly pattern that corresponds to the schedule of water exchange. Such high temporal resolution of monitoring reveals the two-way water quality influences between the pond and the mangrove. It sheds insights that can possibly lead to refinement of water exchange practice and water sampling schedule given the temporal variations of the water quality both inside and outside the pond. It thus enables us to take a step closer in adopting more sustainable farming practices despite increasing pollution in the surrounding areas.

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  13. Commercial-scale in-pond raceway system piques catfish farmers interest in west Alabama

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Construction of a commercial-scale fixed floor In-pond Raceway System (IPRS) began in December 2006 on a 430-water acre farm in Dallas County, AL. The initial IPRS was installed in a traditional 6-acre earthen pond (since the construction of this initial unit, several other farmers have built simila...

  14. Economic feasibility of an in-pond raceway system for commercial catfish production in west Alabama

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The endeavor of this project was to improve profitability of catfish farming by demonstrating methods to achieve high levels of survival, feed performance, and efficiency in a commercial farm setting. A commercial-scale, in-pond raceway system was constructed in 2007 in a 6.0 ac earthen pond on a ca...

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  16. A highly sensitive underwater video system for use in turbid aquaculture ponds.

    PubMed

    Hung, Chin-Chang; Tsao, Shih-Chieh; Huang, Kuo-Hao; Jang, Jia-Pu; Chang, Hsu-Kuang; Dobbs, Fred C

    2016-01-01

    The turbid, low-light waters characteristic of aquaculture ponds have made it difficult or impossible for previous video cameras to provide clear imagery of the ponds' benthic habitat. We developed a highly sensitive, underwater video system (UVS) for this particular application and tested it in shrimp ponds having turbidities typical of those in southern Taiwan. The system's high-quality video stream and images, together with its camera capacity (up to nine cameras), permit in situ observations of shrimp feeding behavior, shrimp size and internal anatomy, and organic matter residues on pond sediments. The UVS can operate continuously and be focused remotely, a convenience to shrimp farmers. The observations possible with the UVS provide aquaculturists with information critical to provision of feed with minimal waste; determining whether the accumulation of organic-matter residues dictates exchange of pond water; and management decisions concerning shrimp health. PMID:27554201

  17. Performance of an intensive pond system treating municipal wastewater in a cold region.

    PubMed

    Wang, B; Qi, P; Wang, L; Lu, W; Liu, S; Zhao, F

    2005-01-01

    A full-scale intensive pond system (IPS) with shorter HRT was designed, constructed and operated in Jining, Inner-Mongolia for the treatment of municipal wastewater, which is a mixed domestic and industrial wastewater characterized by quite high SS and lower BOD5/COD ratio values or lower biodegradability. Therefore, the pond system was designed as an integrated intensive pond system (IIPS) consisting of settling/anaerobic pond (SAP), intensified anaerobic pond (IAP), facultative pond (FP), and polishing ponds (PPs). In order to improve the performance of the IPS, some intensified measures were made, including inlet and outlet even-distribution systems of each unit pond, package of biofilm carrier in IAP for the increase and even distribution of biomass; overflow waterfalls on the dikes between unit ponds for the increase of DO in pond water, gravel filtration dike (or dam) for removing suspended solids including algae, which have improved the performance of the IPS remarkably in terms of removal of main pollutants, such as SS, COD, BOD5, TN, NH3-N, TP and total bacteria. The final effluent from the IPS in warm seasons from May to October were SS 7.2-10.8 mg/L, BOD5 8.5-19.6 mg/L, COD 44.1 - 76.5 mg/L, and NH3-N 1.5-10.2 mg/L, which well meet Chinese national discharge standard (2nd class) of secondary municipal wastewater treatment plants, i.e. BOD5 and SS 30 mg/L respectively, COD 100 mg/L, and NH3-N 25 mg/L. PMID:16114663

  18. Tomorrow`s energy today for cities and counties -- Alternative wastewater treatment: Advanced Integrated Pond systems

    SciTech Connect

    Not Available

    1993-10-01

    This report provides a discussion of the design, construction, operation, and maintenance of the Advanced Integrated Pond System as an alternative for other more costly municipal waste water treatment plants.

  19. Principles of Design And Operations Of Wastewater Treatment Pond Systems For Plant Operators, Engineers, And Managers

    EPA Science Inventory

    Wastewater pond systems provide reliable, low cost, and relatively low maintenance treatment for municipal and industrial discharges. However, they do have certain design, operations, and maintenance requirements. While the basic models have not changed in the 30-odd years sinc...

  20. Exceeding tertiary standards with a pond/reed bed system in Norway.

    PubMed

    Browne, W; Jenssen, P D

    2005-01-01

    At Vidaråsen in Norway sewage from a community consisting of 160 people, including a dairy, a food processing workshop, a bakery and a laundry is treated using a pond/reed bed system. The system consists of sludge settlement, pre-treatment surface/vertical-flow constructed wetlands, a 5 m deep enhanced facultative pond, three stabilization ponds, a planted sand filter and finally two horizontal-flow constructed wetlands filled with lightweight aggregate (Filtralite-P). The enhanced facultative pond and the primary stabilization pond are equipped with Flowform-cascades, which provide year-round aeration, rhythmical treatment and mixing of wastewater in the ponds. Treatment performance during the first five years has been high and unaffected by harsh winter conditions. Average phosphorus discharge from the system is 0.25 mg/l with total nitrogen 4 mg/l, total organic carbon (TOC) 5 mg/l and thermo-tolerant coliforms < 100/100 ml. The system is ecologically diverse and supports abundant populations of higher aquatic life such as ducks, amphibians and carp. PMID:16042271

  1. A highly sensitive underwater video system for use in turbid aquaculture ponds

    PubMed Central

    Hung, Chin-Chang; Tsao, Shih-Chieh; Huang, Kuo-Hao; Jang, Jia-Pu; Chang, Hsu-Kuang; Dobbs, Fred C.

    2016-01-01

    The turbid, low-light waters characteristic of aquaculture ponds have made it difficult or impossible for previous video cameras to provide clear imagery of the ponds’ benthic habitat. We developed a highly sensitive, underwater video system (UVS) for this particular application and tested it in shrimp ponds having turbidities typical of those in southern Taiwan. The system’s high-quality video stream and images, together with its camera capacity (up to nine cameras), permit in situ observations of shrimp feeding behavior, shrimp size and internal anatomy, and organic matter residues on pond sediments. The UVS can operate continuously and be focused remotely, a convenience to shrimp farmers. The observations possible with the UVS provide aquaculturists with information critical to provision of feed with minimal waste; determining whether the accumulation of organic-matter residues dictates exchange of pond water; and management decisions concerning shrimp health. PMID:27554201

  2. Sewage treatment in integrated system of UASB reactor and duckweed pond and reuse for aquaculture.

    PubMed

    Mohapatra, D P; Ghangrekar, M M; Mitra, A; Brar, S K

    2012-06-01

    The performance of a laboratory-scale upflow anaerobic sludge blanket (UASB) reactor and a duckweed pond containing Lemna gibba was investigated for suitability for treating effluent for use in aquaculture. While treating low-strength sewage having a chemical oxygen demand (COD) of typically less than 200 mg/L, with an increase in hydraulic retention time (HRT) from 10.04 to 33.49 h, COD removal efficiency of the UASB reactor decreased owing to a decrease in organic loading rate (OLR) causing poor mixing in the reactor. However, even at the lower OLR (0.475 kg COD/(m3 x d)), the UASB reactor gave a removal efficiency of 68% for COD and 74% for biochemical oxygen demand (BOD). The maximum COD, BOD, ammonia-nitrogen and phosphate removal efficiencies of the duckweed pond were 40.77%, 38.01%, 61.87% and 88.57%, respectively. Decreasing the OLR by increasing the HRT resulted in an increase in efficiency of the duckweed pond for removal of ammonia-nitrogen and phosphate. The OLR of 0.005 kg COD/(m2 x d) and HRT of 108 h in the duckweed pond satisfied aquaculture quality requirements. A specific growth rate of 0.23% was observed for tilapia fish fed with duckweed harvested from the duckweed pond. The economic analysis proved that it was beneficial to use the integrated system of a UASB reactor and a duckweed pond for treatment of sewage. PMID:22856320

  3. Conceptual design of the Truscott brine lake solar-pond system, volume 1: Utility-independent scenario

    NASA Astrophysics Data System (ADS)

    1981-06-01

    A conceptual design was performed for a series of solar pond systems to provide pumping power for chloride control in the Red River Basin. In the chloride control project, briny waters are diverted so as not to pollute portable water. The diverted brine is stored in a dammed natural basin where, with the aid of natural evaporation, the brine is concentrated to the salinities required for the solar ponds. The brine is transferred to the ponds and injected at the proper levels to establish the gradients and storage layers. The solar ponds are to be located within the Truscott, Texas brine impoundment lake. Heat will be extracted from the ponds and used to drive organic Rankine-cycle turbine generators. The electricity produced will serve the pumping needs of the chloride control project, pump brine from the natural source to the evaporation ponds, pump concentrated brine from the evaporation ponds to the solar ponds, maintain the solar ponds, and supply all system parasitic loads. It was found that five solar ponds with eight organic Rankine-cycle turbine-generators would serve both the average and peaking power requirements of the pumping stations in the Truscott area as they come on-line.

  4. Taenia eggs in a stabilization pond system with poor hydraulics: concern for human cysticercosis?

    PubMed

    Verbyla, Matthew E; Oakley, Stewart M; Lizima, Louis A; Zhang, Jie; Iriarte, Mercedes; Tejada-Martinez, Andres E; Mihelcic, James R

    2013-01-01

    The objective of this study is to compare the removal of Taenia eggs to the removal of Ascaris eggs in a wastewater stabilization pond system consisting of three ponds in series, where the hydraulic residence time distribution has been characterized via a tracer study supported by computational fluid dynamics modeling. Despite a theoretical hydraulic retention time of 30 days, the peak dye concentration was measured in the effluent of the first pond after only 26 hours. The smaller-sized Taenia eggs were detected in higher concentrations than Ascaris eggs in the raw wastewater. Ascaris eggs were not detected in the pond system effluent, but 45 Taenia eggs/L were detected in the system effluent. If some of these eggs were of the species Taenia solium, and if the treated wastewater were used for the irrigation of crops for human consumption, farmers and consumers could potentially be at risk for neurocysticercosis. Thus, limits for Taenia eggs in irrigation water should be established, and precautions should be taken in regions where pig taeniasis is endemic. The results of this study indicate that the theoretical hydraulic retention time (volume/flow) of a pond is not always a good surrogate for helminth egg removal. PMID:24355860

  5. Microbial and chemical profile of a ponds system for the treatment of landfill leachate.

    PubMed

    Fernandes, Heloísa; Viancelli, Aline; Martins, Claudia L; Antonio, Regina V; Costa, Rejane H R

    2013-10-01

    The present study describes the behavior of spatio-temporal variation of parameters and microbial profile of a pilot stabilization ponds system, consisted of three serial ponds, for the treatment of landfill leachate. Bacterial diversity was determined through molecular techniques (FISH, PCR and phylogenic analysis), while the phytoplankton community was evaluated through optical microscopy and quantified by the Sedgewick-Rafter chamber. Physicochemical parameters were also evaluated. The ponds system presented the following removal efficiency: 56% for TCOD; 83% for SBOD5 and 82% for N-NH4(+). Moreover, the analysis of chlorophyll a and DO showed stratification in the mass of water by the vertical profile. The analysis of the phytoplankton community showed a low number of species, with a predominance of Chlamydomonas sp. and presence of Cryptomonas sp. in lower density. The bacterial diversity analysis showed the presence of Planctomycetales, Verrucomicrobiales, some Desulfovibionaceae sulfate-reducing bacteria and Pseudomonas sp. PMID:23206517

  6. Reconstruction and operation of the El Paso Solar Pond with a geosynthetic clay liner system

    SciTech Connect

    Lu, H.; Swift, A.H.P.

    1996-12-31

    After the original XR-5 membrane liner failed in 1992, the El Paso Solar Pond was reconstructed and operated with a geosynthetic clay liner (GCL) system. The solar pond is approximately 3,000 m{sup 2} in surface area, and 3.2 meters deep with a 15{degree} side-wall slope. A new heat extraction system includes 15-cm (6-inch) rubber hoses and two redesigned polypropylene diffusers. A new automated instrumentation system was developed for monitoring pond status. It uses a newly developed scanner combined with a computer for both position control and data logging. The salinity gradient was established using a new scanning method, as opposed to the previously used fixed point method. Fresh water was injected into brine through a newly designed PVC bar shaped diffuser, which scans automatically within preset regions. After two months, the pond bottom reached 80 C and heat extraction began. The performance of the GCL system, characterized by its hydraulic conductivity, has been monitored, and generates the first full scale, elevated temperature data for a GCL system. Preliminary hydraulic conductivity data indicate values comparable with other clay liner systems.

  7. Sewage treatment in a single pond system at East Kolkata Wetland, India.

    PubMed

    Sarkar, Subhasis; Ghosh, Phani Bhusan; Mukherjee, Koushik; Sil, Alok Kumar; Saha, Tapan

    2009-01-01

    East Kolkata Wetland (EKW), a Ramsar site, greatly contributes towards purification of city sewage employing single pond system. However, the underlying mechanism remains unknown. Therefore to gain an insight, in this study efforts have been made to understand the rate of biodegradation and the time dependent changes of different physicochemical factors and their interactions that are involved in the process. For this purpose, different parameters such as BOD, COD, faecal coliforms etc. have been measured at different time intervals during the purification process. The results reveal that biodegradation rate at EKW pond is very high and wastewater gets stabilized within 10 days of retention. The higher rate of biodegradation in pond system at EKW (k = 0.7 day(-1)) than in laboratory based in vitro experiment (k = 0.12 day(-1)) reveals the important contribution from other environmental components that are unique for this system. The results also demonstrate the significant influence (P< or =0.01) of temperature, pH and dissolved oxygen on the purification of waste water. Thus the current study provides an insight about the optimal pathway of gradual improvement of wastewater quality in the single pond system at EKW and may serve to explore the inherent mechanism to a great extent. PMID:19901462

  8. Diel changes in water chemistry in an arsenic-rich stream and treatment-pond system

    USGS Publications Warehouse

    Gammons, C.H.; Grant, T.M.; Nimick, D.A.; Parker, S.R.; DeGrandpre, M.D.

    2007-01-01

    Arsenic concentrations are elevated in surface waters of the Warm Springs Ponds Operable Unit (WSPOU), located at the head of the upper Clark Fork River Superfund site, Montana, USA. Arsenic is derived from historical deposition of smelter emissions (Mill and Willow Creeks) and historical mining and milling wastes (Silver Bow Creek). Although long-term monitoring has characterized the general seasonal and flow-related trends in As concentrations in these streams and the pond system used to treat Silver Bow Creek water, little is known about solubility controls and sorption processes that influence diel cycles in As concentrations. Diel (24-h) sampling was conducted in July 2004 and August 2005 at the outlet of the treatment ponds, at two locations along a nearby reconstructed stream channel that diverts tributary water around the ponds, and at Silver Bow Creek 2??km below the ponds. Dissolved As concentration increased up to 51% during the day at most of the stream sites, whereas little or no diel change was displayed at the treatment-pond outlet. The strong cycle in streams is explained by pH- and temperature-dependent sorption of As onto hydrous metal oxides or biofilms on the streambed. Concentrations of dissolved Ca2+ and HCO3- at the stream sites showed a diel temporal pattern opposite to that of As, and geochemical modeling supports the hypothesis that the concentrations of Ca2+ and HCO3- were controlled by precipitation of calcite during the warm afternoon hours when pH rose above 9.0. Nightly increases in dissolved Mn and Fe(II) concentrations were out of phase with concentrations of other divalent cations and are more likely explained by redox phenomena. ?? 2007 Elsevier B.V. All rights reserved.

  9. Thermo-tolerant coliform bacteria decay rates in a full scale waste stabilization pond system in northeast Brazil.

    PubMed

    Macedo, S L; Araújo, A L C; Pearson, H W

    2011-01-01

    This paper presents the results for thermo-tolerant coliform (TTC) decay rates (K(b)) in a full scale WSP system located in Natal-RN, northeast Brazil. The series comprises a primary facultative pond (2 m deep), followed by two maturation ponds (1.5 m deep) giving a total area of 11 ha. The influent sewage and the pond effluents were monitored weekly during a seven month period. The results showed that the K(b) values predicted by the Marais equation assuming a hydraulic regime of complete mixing overestimated TTC die-off rates. The K(b) value adopted in the project design was 6.20 d(-1) but the mean value found for the WSP system during the monitoring programme was only 0.85 d(-1). This value is low compared to the values cited in the literature for shallow ponds (<1.25 m deep) but similar to values for deeper ponds. The sub optimal TTC removal rate in this WSP system may be caused by the adoption of too high a K(b) value at the design stage and the negative influence of high wind conditions on the mixing regime in the water columns of the ponds. Thus values for K(b) adopted at the design stage of WSP systems should be coherent with the hydraulic flow model, the type of pond, pond depth, and with the surface organic loading. PMID:21436574

  10. Assessment of a full-scale duckweed pond system for septage treatment.

    PubMed

    Papadopoulos, F H; Tsihrintzis, V A

    2011-01-01

    Environmental conditions and wastewater treatment performance in a full-scale duckweed pond system are presented. The treatment system consisted of three stabilization ponds in series and was fed with septage. Vacuum trucks pumped the septage from residential holding tanks and discharged it to the system daily. The inflow rates averaged 36 m3 d(-1) in the cold season and 60 m3 d(-1) in the warm season. Duckweed (Lemna minor) colonized the ponds in the warm months and survived during the cold season. Because of the difficult process for harvesting the duckweed biomass, the investigation of the treatment efficiency was carried out without plant harvesting. Samples were collected from the vacuum trucks and from the exit of each pond and were analysed for physicochemical and microbiological parameters over a period of 12 months. The results showed that the duckweed mat suppressed algal biomass, which in turn led to anoxic and neutral pond conditions. On an annual basis, the duckweed system sufficiently removed BOD5 (94%), NH4+ (72%) and E. coli (99.65%), with lower removal of TSS (63%) and Enterococci (91.76%). A slight increase (1.1%) was recorded for o-PO4(3-). Between the two sampling seasons, BOD5 and TSS removal efficiencies were higher in the cold season with the longer retention time. Similar removal values in the warm and the cold season were found for nutrients and bacteria. These findings indicate that BOD5 and TSS removals are less temperature-dependent at higher retention times, while ammonia nitrogen and bacterial removals are substantially influenced by temperature as well as retention time. PMID:21879554

  11. A Summary Description of a Computer Program Concept for the Design and Simulation of Solar Pond Electric Power Generation Systems

    NASA Technical Reports Server (NTRS)

    1984-01-01

    A solar pond electric power generation subsystem, an electric power transformer and switch yard, a large solar pond, a water treatment plant, and numerous storage and evaporation ponds. Because a solar pond stores thermal energy over a long period of time, plant operation at any point in time is dependent upon past operation and future perceived generation plans. This time or past history factor introduces a new dimension in the design process. The design optimization of a plant must go beyond examination of operational state points and consider the seasonal variations in solar, solar pond energy storage, and desired plant annual duty-cycle profile. Models or design tools will be required to optimize a plant design. These models should be developed in order to include a proper but not excessive level of detail. The model should be targeted to a specific objective and not conceived as a do everything analysis tool, i.e., system design and not gradient-zone stability.

  12. Simulation model for the performance analysis of roof pond systems for heating and cooling

    SciTech Connect

    Tavana, M.; Kammerud, R.; Akbari, H.; Borgers, T.

    1980-06-01

    A detailed computer model has been developed for simulating the dynamic thermal behavior of roof pond systems. The model is composed of outer movable insulation, an optional evaporative water layer over water bags on steel decking, and an inner movable insulation. A control strategy for the movable insulations which provides near optimum thermal performance is included in the model. An hourly thermal balance analysis of the system is performed using theoretical and/or empirical expressions to determine the heat transfer coefficients for each of the surfaces in the model. The model has been used to study the effect on system thermal performance of (1) the R-value of both the top and bottom movable insulations; (2) the depth of the pond water, and (3) the depth of the evaporative layer. The heating and cooling potentials of the roof pond have also been investigated in four climates. The model was developed for incorporation into the public domain building energy analysis computer program BLAST.

  13. Freshwater ponds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This book chapter summarizes aquaculture pond ecology. The underlying theme is how ponds supply essential life-support functions (food, oxygen, and waste treatment) and how those functions are subsidized by external resources as culture intensity increases. Ponds are confined bodies of standing wate...

  14. Solar ponds

    SciTech Connect

    Jayadev, T.S.; Edesess, M.

    1980-04-01

    This report first describes the different types of solar ponds including the nonconvecting salt gradient pond and various saltless pond designs. It then discusses the availability and cost of salts for salt gradient ponds, and compares the economics of salty and saltless ponds as a function of salt cost. A simple computational model is developed to approximate solar pond performance. This model is later used to size solar ponds for district heating and industrial process heat applications. For district heating, ponds are sized to provide space conditioning for a group of homes, in different regions of the United States. Size requirements is on the order of one acre for a group of 25 to 50 homes. An economic analysis is performed of solar ponds used in two industrial process heat applications. The analysis finds that solar ponds are competitive when conventional heat sources are priced at $5 per million Btu and expected to rise in price at a rate of 10% per year. The application of solar ponds to the generation of electricity is also discussed. Total solar pond potential for displacing conventional energy sources is estimated in the range of from one to six quadrillion Btu per year in the near and intermediate future.

  15. Solar-thermal-energy collection/storage-pond system

    DOEpatents

    Blahnik, D.E.

    1982-03-25

    A solar thermal energy collection and storage system is disclosed. Water is contained, and the water surface is exposed directly to the sun. The central part of an impermeable membrane is positioned below the water's surface and above its bottom with a first side of the membrane pointing generally upward in its central portion. The perimeter part of the membrane is placed to create a watertight boundary separating the water into a first volume which is directly exposable to the sun and which touches the membranes first side, and a second volumn which touches the membranes second side. A salt is dissolved in the first water volume.

  16. Solar ponds

    SciTech Connect

    Jayadev, T.S.; Edesess, M.

    1980-04-01

    The different types of solar ponds are described, including the nonconvecting salt gradient pond and various saltless pond designs. Then the availability and cost of salts for salt gradient ponds are discussed and costs are compared. A simple computational model is developed to approximate solar pond performance. This model is later used to size solar ponds for district heating and industrial process heat applications. For district heating, ponds are sized to provide space conditioning for a group of homes, in different regions of the United States. Size requirement is on the order of one acre for a group of 25 to 50 homes. An economic analysis is performed of solar ponds used in two industrial process heat applications. The analysis finds that solar ponds are competitive when conventional heat sources are priced at $5 per million Btu and expected to rise in price at a rate of 10% per year. The application of solar ponds to the generation of electricity is also discussed. Total solar pond potential for displacing conventional energy sources is estimated in the range of from one to six quadrillion Btu per year in the near and intermediate future.

  17. Evaluation of solar pond performance

    SciTech Connect

    Wittenberg, L.J.

    1980-01-01

    The City of Miamisburg, Ohio, constructed during 1978 a large, salt-gradient solar pond as part of its community park development project. The thermal energy stored in the pond is being used to heat an outdoor swimming pool in the summer and an adjacent recreational building during part of the winter. This solar pond, which occupies an area of 2020 m/sup 2/ (22,000 sq. ft.), was designed from experience obtained at smaller research ponds located at Ohio State University, the University of New Mexico and similar ponds operated in Israel. During the summer of 1979, the initial heat (40,000 kWh, 136 million Btu) was withdrawn from the solar pond to heat the outdoor swimming pool. All of the data collection systems were installed and functioned as designed so that operational data were obtained. The observed performance of the pond was compared with several of the predicted models for this type of pond. (MHR)

  18. A case study of enteric virus removal and insights into the associated risk of water reuse for two wastewater treatment pond systems in Bolivia.

    PubMed

    Symonds, E M; Verbyla, M E; Lukasik, J O; Kafle, R C; Breitbart, M; Mihelcic, J R

    2014-11-15

    Wastewater treatment ponds (WTP) are one of the most widespread treatment technologies in the world; however, the mechanisms and extent of enteric virus removal in these systems are poorly understood. Two WTP systems in Bolivia, with similar overall hydraulic retention times but different first stages of treatment, were analyzed for enteric virus removal. One system consisted of a facultative pond followed by two maturation ponds (three-pond system) and the other consisted of an upflow anaerobic sludge blanket (UASB) reactor followed by two maturation (polishing) ponds (UASB-pond system). Quantitative polymerase chain reaction with reverse transcription (RT-qPCR) was used to measure concentrations of norovirus, rotavirus, and pepper mild mottle virus, while cell culture methods were used to measure concentrations of culturable enteroviruses (EV). Limited virus removal was observed with RT-qPCR in either system; however, the three-pond system removed culturable EV with greater efficiency than the UASB-pond system. The majority of viruses were not associated with particles and only a small proportion was associated with particles larger than 180 μm; thus, it is unlikely that sedimentation is a major mechanism of virus removal. High concentrations of viruses were associated with particles between 0.45 and 180 μm in the UASB reactor effluent, but not in the facultative pond effluent. The association of viruses with this size class of particles may explain why only minimal virus removal was observed in the UASB-pond system. Quantitative microbial risk assessment of the treated effluent for reuse for restricted irrigation indicated that the three-pond system effluent requires an additional 1- to 2-log10 reduction of viruses to achieve the WHO health target of <10(-4) disability-adjusted life years (DALYs) lost per person per year; however, the UASB-pond system effluent may require an additional 2.5- to 4.5-log10 reduction of viruses. PMID:25129566

  19. Preparation for Retrievals from Sellafield Legacy Ponds Installation of the Gantry Refurbishment System

    SciTech Connect

    Ellison, M.

    2008-07-01

    Retrieval of sludge and fuel from the First Generation Magnox Fuel Storage Pond, and its safe long term storage is one of the NDA's top priorities in the UK clean up programme. The plant is currently undergoing a series of major modifications in preparation for the retrievals operations. The most visible example of these modifications is the Gantry Refurbishment System (GRS), a major work platform which has recently been lifted onto the pond long travel girders used by the Skip Handler. This paper describes the design, manufacture, works test, and site installation of this major piece of equipment. The installation lift, involving the use of an 800Te crane was one of the largest lifts undertaken at Sellafield. The GRS is a mobile platform structure which is designed to be pushed or pulled along the long travel girders by the Skip Handler. Its principle function is to provide a safe and shielded working platform from which to undertake refurbishment of the Skip Handler long travel girders and support structure. The potential hazards and consequences resulting from the modification were fully understood and controls were put in place to ensure that the risk of carrying out the work was as low as reasonably practicable. The work was authorised by the NII, Sellafield Nuclear Safety Committee and an independent readiness review panel. Despite less than perfect weather in the run up to the lift, the GRS was successfully and safely lifted onto the pond on 18 October 2006, the culmination of three years of planning, engineering and construction. (authors)

  20. Fate of pesticides in combined paddy rice-fish pond farming systems in northern Vietnam.

    PubMed

    Anyusheva, Maria; Lamers, Marc; La, Nguyen; Nguyen, Van Vien; Streck, Thilo

    2012-01-01

    During the last decades, high population growth and export-oriented economics in Vietnam have led to a tremendous intensification of rice production, which in turn has significantly increased the amount of pesticides applied in rice cropping systems. Since pesticides are toxic by design, there is a natural concern on the impact of their presence in the environment on human health and environmental quality. The present study was designed to examine the water regime and fate of pesticides (fenitrothion, dimethoate) during two consecutive rice crop seasons in combined paddy rice-fish pond farming systems in northern Vietnam. Major results revealed that 5 and 41% (dimethoate), and 1 and 17% (fenitrothion) of the applied mass of pesticides were lost from the paddy field to the adjacent fish pond during spring and summer crop seasons, respectively. The decrease of pesticide concentration in paddy surface water was very rapid with dissipation half-life values of 0.3 to 0.8 and 0.2 d for dimethoate and fenitrothion, respectively. Key factors controlling the transport of pesticides were water solubility and paddy water management parameters, such as hydraulic residence time and water holding period. Risk assessment indicates that the exposure to toxic levels of pesticides for aquaculture (, ) is significant, at least shortly after pesticide application. PMID:22370414

  1. Par Pond water balance

    SciTech Connect

    Hiergesell, R.A.; Dixon, K.L.

    1996-06-01

    A water budget for the Par Pond hydrologic system was established in order to estimate the rate of groundwater influx to Par Pond. This estimate will be used in modeling exercises to predict Par Pond reservoir elevation and spillway discharge in the scenario where Savannah River water is no longer pumped and discharged into Par Pond. The principal of conservation of mass was used to develop the water budget, where water inflow was set equal to water outflow. Components of the water budget were identified, and the flux associated with each was determined. The water budget was considered balanced when inflow and outflow summed to zero. The results of this study suggest that Par Pond gains water from the groundwater system in the upper reaches of the reservoir, but looses water to the groundwater system near the dam. The rate of flux of groundwater from the water table aquifer into Par Pond was determined to be 13 cfs. The rate of flux from Par Pond to the water table aquifer near the dam was determined to be 7 cfs.

  2. Environmental sustainability assessment of a microalgae raceway pond treating aquaculture wastewater: From up-scaling to system integration.

    PubMed

    Sfez, Sophie; Van Den Hende, Sofie; Taelman, Sue Ellen; De Meester, Steven; Dewulf, Jo

    2015-08-01

    The environmental sustainability of aquaculture wastewater treatment by microalgal bacterial flocs (MaB-flocs) in an outdoor raceway pond was analyzed using life cycle assessment. Pikeperch aquaculture wastewater treated at pilot scale (Belgium; 28m(2)) and industrial scale (hypothetical up-scaling; 41 ponds of 245m(2)) were compared. The integration of the MaB-floc raceway pond in a broader aquaculture waste treatment system was studied, comparing the valorisation of MaB-flocs as shrimp feed and as biogas. Up-scaling improves the resource footprint of the plant (848MJex,CEENEkg(-1) MaB-floc TSS at pilot scale and 277MJex,CEENEkg(-1) MaB-floc TSS at industrial scale) as well as its carbon footprint and eutrophication potential. At industrial scale, the valorisation of MaB-flocs as shrimp feed is overall more sustainable than as biogas but improvements should be made to reduce the energy use of the MaB-floc raceway pond, especially by improving the energy-efficiency of the pond stirring system. PMID:25965258

  3. Surveillance system using the CCTV at the fuel transfer pond in the Tokai reprocessing plant

    SciTech Connect

    Hayakawa, T.; Fukuhara, J.; Ochiai, K.; Ohnishi, T.; Ogata, Y.; Okamoto, H. )

    1991-01-01

    The Fuel Transfer Pond (FTP) in the Tokai Reprocessing Plant (TRP) is a strategic point for safeguards. Spent fuels, therefore, in the FTP have been surveyed by the surveillance system using the underwater CCTV. This system was developed through the improvement of devices composed of cameras and VCRs and the provision of tamper resistance function as one of the JASPAS (Japan Support Program for Agency Safeguards) program. The purpose of this program is to realize the continuous surveillance of the slanted tunnel through which the spent fuel on the conveyor is moved from the FTP to the Mechanical Processing Cell (MPC). This paper reports that, when this surveillance system is applied to an inspection device, the following requirements are needed: To have the ability of continuous and unattended surveillance of the spent fuel on the conveyor path from the FTP to the MPC; To have the tamper resistance function for continuous and unattended surveillance of the spent fuel.

  4. Advanced treatment of refractory organic pollutants in petrochemical industrial wastewater by bioactive enhanced ponds and wetland system.

    PubMed

    Liu, Shuo; Ma, Qiusha; Wang, Baozhen; Wang, Jifu; Zhang, Ying

    2014-05-01

    A large-scale combined ponds-wetland system was applied for advanced treatment of refractory pollutants in petrochemical industrial wastewater. The system was designed to enhance bioactivity and biological diversity, which consisted of anaerobic ponds (APs), facultative ponds (FPs), aerobic pond and wetland. The refractory pollutants in the petrochemical wastewater to be treated were identified as alkanes, chloroalkanes, aromatic hydrocarbons, and olefins, which were significantly degraded and transformed along with the influent flowing through the enhanced bioactive ponds-wetland system. 8 years of recent operational data revealed that the average removal rate of stable chemical oxygen demand (COD) was 42.7 % and that influent COD varied from 92.3 to 195.6 mg/L. Final effluent COD could reach 65.8 mg/L (average). COD removal rates were high in the APs and FPs and accounted for 75 % of the total amount removed. This result indicated that the APs and FPs degraded refractory pollutants through the facilitation of bacteria growth. The changes in the community structures of major microbes were assessed by 16SrDNA-denaturing gradient gel electrophoresis. The same analysis was used to identify the main bacterial function for the removal of refractory pollutants in the APs and FPs. The APs and FPs displayed similar microbial diversities, and some of the identified bacteria degraded and removed refractory pollutants. The overall results proved the applicability, stability, and high efficiency of the ponds-wetland system with enhanced bioactivity in the advanced removal of refractory pollutants from petrochemical industrial wastewater. PMID:24578265

  5. The effects of flow-path modification on water-quality constituent retention in an urban stormwater detention pond and wetland system, Orlando, Florida

    USGS Publications Warehouse

    Gain, W.S.

    1996-01-01

    Changes in constituent retention in a wet stormwater-detention pond and wetland system in Orlando, Florida, were evaluated following the 1988 installation of a flow barrier which approximately doubled the flow path and increased detention time in the pond. The pond and wetland were arranged in series so that stormwater first enters the pond and overflows into the wetland before spilling over to the regional stream system. Several principal factors that contribute to constituent retention were examined, including changes in pond-water quality between storms, stormwater quality, and pond-water flushing during storms. A simple, analytical pond-water mixing model was used as the basis for interpreting changes in retention efficiencies caused by pond modification. Retention efficiencies were calculated by a modified event-mean concentration efficiency method using a minimum variance unbiased estimator approach. The results of this study generally support the hypothesis that changes in the geometry of stormwater treatment systems can significantly affect the constituent retention efficiency of the pond and wetland system. However, the results also indicate that these changes in efficiency are caused not only by changes in residence time, but also by changes in stormwater mixing and pond water flushing during storms. Additionally, the use of average efficiencies as indications of treatment effectiveness may fail to account for biases associated with sample distribution and independent physical properties of the system, such as the range and concentrations of constituents in stormwater inflows and stormwater volume. Changes in retention efficiencies varied among chemical constituents and were significantly different in the pond and wetland. Retention efficiency was related to inflow concentration for most constituents. Increased flushing of the pond after modification caused decreases in retention efficiencies for constituents that concentrate in the pond between storms

  6. Modelling the fate of pesticides in paddy rice-fish pond farming system in Northern Vietnam

    NASA Astrophysics Data System (ADS)

    Lamers, M.; Nguyen, N.; Streck, T.

    2012-04-01

    During the last decade rice production in Vietnam has tremendously increased due to the introduction of new high yield, short duration rice varieties and an increased application of pesticides. Since pesticides are toxic by design, there is a natural concern on the possible impacts of their presence in the environment on human health and environment quality. In North Vietnam, lowland and upland rice fields were identified to be a major non-point source of agrochemical pollution to surface and ground water, which are often directly used for domestic purposes. Field measurements, however, are time consuming, costly and logistical demanding. Hence, quantification, forecast and risk assessment studies are hampered by a limited amount of field data. One potential way to cope with this shortcoming is the use of process-based models. In the present study we developed a model for simulating short-term pesticide dynamics in combined paddy rice field - fish pond farming systems under the specific environmental conditions of south-east Asia. Basic approaches and algorithms to describe the key underlying biogeochemical processes were mainly adopted from the literature to assure that the model reflects the current standard of scientific knowledge and commonly accepted theoretical background. The model was calibrated by means of the Gauss-Marquardt-Levenberg algorithm and validated against measured pesticide concentrations (dimethoate and fenitrothion) during spring and summer rice crop season 2008, respectively, of a paddy field - fish pond system typical for northern Vietnam. First simulation results indicate that our model is capable to simulate the fate of pesticides in such paddy - fish pond farming systems. The model efficiency for the period of calibration, for example, was 0.97 and 0.95 for dimethoate and fenitrothion, respectively. For the period of validation, however, the modeling efficiency slightly decreased to 0.96 and 0.81 for dimethoate and fenitrothion

  7. The effect of aeration and effluent recycling on domestic wastewater treatment in a pilot-plant system of duckweed ponds.

    PubMed

    Ben-shalom, Miriam; Shandalov, Semion; Brenner, Asher; Oron, Gideon

    2014-01-01

    Three pilot-scale duckweed pond (DP) wastewater treatment systems were designed and operated to examine the effect of aeration and effluent recycling on treatment efficiency. Each system consisted of two DPs in series fed by pre-settled domestic sewage. The first system (duckweed+ conventional treatment) was 'natural' and included only duckweed plants. The second system (duckweed aeration) included aeration in the second pond. The third system (duckweed+ aeration+ circulation) included aeration in the second pond and effluent recycling from the second to the first pond. All three systems demonstrated similarly efficient removal of organic matter and nutrients. Supplemental aeration had no effect on either dissolved oxygen levels or on pollutant removal efficiencies. Although recycling had almost no influence on nutrient removal efficiencies, it had a positive impact on chemical oxygen demand and total suspended solids removals due to equalization of load and pH, which suppressed algae growth. Recycling also improved the appearance and growth rate of the duckweed plants, especially during heavy wastewater loads. PMID:24473305

  8. Evaluation of a multiport groundwater monitoring system

    SciTech Connect

    Gilmore, T.J.; Hall, S.H.; Olsen, K.B.; Spane, F.A. Jr.

    1991-03-01

    In 1988 and 1989, Pacific Northwest Laboratory installed a multiport groundwater monitoring system in two wells on the Hanford Site: one near the 216-B-3 Pond in the center of the Hanford Site and one just north of the 300 Area near the Columbia River. The system was installed to provide the US Department of Energy with needed three-dimensional data on the vertical distribution of contaminants and hydraulic heads on the Hanford Site. This study evaluates the ability of the multiport system to obtain hydrogeologic data at multiple points vertically in a single borehole, and addresses the representativeness of the data. Data collected from the two wells indicate that the multiport system is well suited for groundwater monitoring networks requiring three-dimensional characterization of the hydrogeologic system. A network of these systems could provide valuable information on the hydrogeologic environment. However, the advantages of the multiport system diminish when the system is applied to long-term monitoring networks (30+ years) and to deeper wells (<300 ft). For shallow wells, the multiport system provides data in a cost-effective manner that would not be reasonably obtainable with the conventional methods currently in use at the Hanford Site. 17 refs., 28 figs., 6 tabs.

  9. Removal of bacterial and viral faecal indicator organisms in a waste stabilization pond system in Choconta, Cundinamarca (Colombia).

    PubMed

    Campos, C; Guerrero, A; Cárdenas, M

    2002-01-01

    A major objective for domestic wastewater treatment using waste stabilization pond systems is the removal of pathogenic microorganisms. Traditional evaluation parameters for faecal contamination are the total and faecal coliforms. However, epidemiological studies, environmental resistance and the behaviour in the treatment systems, show that viruses are an important disease agent and even more resistant to disinfection than bacteria. Therefore, it is important to introduce viruses as a faecal indicator and to compare them with the traditional bacterial indicators. A waste stabilization pond system was evaluated in the municipality of Chocontá, Cundinamarca (Colombia), for the removal of faecal indicators (such as Escherichia coli, Streptococcus faecalis, Clostridium perfringens) and viruses like F+, somatic and Bacteroides fragilis phages. The system includes two facultative ponds in series with a flow of 1555 m3/day. Samples were collected at the entrance of the system, in the two ponds and from the final effluent. Results show a decrease between 0.3 and 4.7 logarithmic units in the bacterial indicators and between 1 and 4.6 logarithmic units with viral indicators. PMID:11833732

  10. Effects of fish barrier screening material on water flow in split-pond aquaculture systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ponds serve two functions as fish-culture units. They hold water and fish, much like the walls of an aquarium, and they produce oxygen and treat wastes produced during culture. Split-ponds separate those two functions to make management easier. A large lagoon that provides the ecological services is...

  11. In situ estimation of water quality parameters in freshwater aquaculture ponds using hyperspectral imaging system

    NASA Astrophysics Data System (ADS)

    Abd-Elrahman, Amr; Croxton, Matthew; Pande-Chettri, Roshan; Toor, Gurpal S.; Smith, Scot; Hill, Jeffrey

    Knowledge of water quality parameters is integral to sustainability of freshwater aquaculture operations that raise ornamental fish. Our objective in this study is to evaluate the ability of a mobile, ground-based hyperspectral (HS) imaging sensor to determine chlorophyll-a (Chl-a) concentrations in working aquaculture ponds, which represent manipulated, shallow, nutrient-rich systems, and to determine the effect of using submerged reflectance targets on the accuracy of Chl-a estimation. We collected Chl-a measurements from aquaculture ponds ranging from 0.8 to 494 μg/L. Chl-a measurements showed a strong correlation with two-band and three-band spectral indices computed from the HS image reflectance. Coefficient of determination ( R2) values of 0.975 and 0.982 were obtained for the two- and three-band models, respectively, using spectra captured from the submerged target at 10 cm depth. Using spectra captured from water (no submerged targets), R2 values were slightly lower at 0.833 and 0.862 for two- and three-band models. Data from the submerged target at 30 cm depth had the lowest correlation with measured chlorophyll-a concentrations, potentially due to variations in water column properties and shadows cast by the platform. Modeling total Phosphorous (P) and Nitrogen (N) concentrations of the collected samples with the spectral indices sensitive to Chl-a concentrations showed a moderate level of correlation. Removing a model outlier (observation with maximum N and P concentrations) led to a significant increase in the models' coefficient of determination ( e.g. from 0.478 to 0.823 for the P model using three-band index values), which highlighted the possibility of using HS imagery to estimate N and P concentrations and the need for more research to model the interrelationships between Chl-a and nutrient concentrations in aquaculture water systems.

  12. Comparison of hydraulics and particle removal efficiencies in a mixed cell raceway and burrows pond rearing system

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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 eff...

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  14. Comparison of hydraulics and particle removal efficiencies in a mixed cell raceway and Burrows pond rearing system

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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 eff...

  15. Comparative evaluation on the performance of bio-rack and shallow pond systems for domestic wastewater treatment.

    PubMed

    Valipour, A; Raman, V K; Badaliansgholikandi, G

    2012-10-01

    Constructed wetlands have been used successfully for treatment of wastewater during the last decades. The bio-rack and shallow pond systems are well engineered wetland process in wastewater treatment. The aim of this study is to compare the potential use of bio-rack and shallow pond systems for domestic wastewater treatment either in presence of high total dissolved solids (TDS) or heavy metal salts. The sewage treatment performance indicates 75.15% & 80.93% chemical oxygen demand (COD), 86.59% & 90.90% biological oxygen demand (BOD5), 27.54% & 15.98% total dissolved solids (TDS), 73.13% & 70.31% total suspended solids (TSS), 8.86% & 3.61% Chlorides, 70.22% & 74.18% ammonia nitrogen (NH3-N), 31.71% & 41.24% phosphate (PO4-P), 92.11% & 96.45% most probable number (MPN) and 93.05% & 98.24% total viable count (TVC) reduction at 10 & 21 h hydraulic retention time (HRT) in bio-rack and shallow pond system respectively. Likewise, the Phragmites sp. and water hyacinth can tolerate TDS up to 9000 and 2000 mg/L. The reduction in TDS is minor (14 & 19%) at the highest tolerable limit whereas the heavy metal reduction is 68 & 65%, 69 & 67%, 67 & 63%, 71 & 69% for Cd, Cu, Ni and Zn in bio-rack and shallow pond system respectively. The overall studies indicate the better treatment efficiency in bio-rack system at low foot print area (91 m2) compared to shallow pond system. PMID:25151708

  16. Septic systems, but not sanitary sewer lines, are associated with elevated estradiol in male frog metamorphs from suburban ponds.

    PubMed

    Lambert, Max R; Giller, Geoffrey S J; Skelly, David K; Bribiescas, Richard G

    2016-06-01

    Suburban neighborhoods are a dominant type of human land use. Many housing regions globally rely on septic systems, rather than sanitary sewers, for wastewater management. There is evidence that septic systems may contaminate waterbodies more than sewer lines. There is also mounting evidence that human activities contaminate waterways with endocrine-disrupting chemicals (EDCs), which alter wildlife sexual development. While endocrine disruption is often associated with intense activities such as agriculture or wastewater treatment plant discharges, recent evidence indicates that endocrine disruption is pervasive in frogs from suburban neighborhoods. In conjunction with other putative EDC sources, one hypothesis is that wastewater is contaminating suburban waterways with EDCs derived from pharmaceuticals or personal care products. Here, we measure estradiol (E2) in metamorphosing green frogs (Rana clamitans) from forested ponds and suburban ponds adjacent to either septic tanks or sanitary sewers. We show that E2 is highest in male frogs from septic neighborhoods and that E2 concentrations are significantly lower in male frogs from forested ponds and from ponds near sewers. These results indicate that septic tanks may be contaminating aquatic ecosystems differently than sewer lines. This pattern contrasts prior work showing no difference in EDC contamination or morphological endocrine disruption between septic and sewer neighborhoods, implying that suburbanization may have varying effects at multiple biological scales like physiology and anatomy. PMID:26795918

  17. Nutrient recovery from domestic wastewater using a UASB-duckweed ponds system.

    PubMed

    El-Shafai, Saber A; El-Gohary, Fatma A; Nasr, Fayza A; van der Steen, N Peter; Gijzen, Huub J

    2007-03-01

    The pilot-scale wastewater treatment system used in this study comprised a 40-l UASB reactor (6-h HRT) followed by three duckweed ponds in series (total HRT 15 days). During the warm season, the treatment system achieved removal values of 93%, 96% and 91% for COD, BOD and TSS, respectively. Residual values of ammonia, TKN and total phosphorus were 0.41 mg N/l, 4.4 mg N/l and 1.11 mg P/l, with removal efficiencies of 98%, 85% and 78%, respectively. The system achieved 99.998% faecal coliform removal during the warm season with final effluent containing 4 x 10(3) cfu/100 ml. During the winter, the system was efficient in removing COD, BOD and TSS but not nutrients. The system was deficient in the removal of faecal coliforms during the winter, producing effluent with 4.7 x 10(5) cfu/100 ml. During the warm season, the N removal consisted of 80% by plant uptake, 5% by sedimentation and 15% unaccounted for. A duckweed production rate of 33 t dry matter per hectare per 8 months was achieved. PMID:16713255

  18. Consortia of microalgae and bacteria in the performance of a stabilization pond system treating landfill leachate.

    PubMed

    Costa, R H R; Martins, C L; Fernandes, H; Velho, V F

    2014-01-01

    This study treated sanitary landfill leachate and was conducted in a pilot-scale system composed of three serial ponds (P1, P2 and P3), followed by a rock filter, in order to evaluate the microbial consortium influence on system performance and to investigate microorganism dynamics in the process. The system was broken into three stages, with a continuous flow rate (Q = 200 L d⁻¹) for 43 weeks. The stages were as follows: conventional operation (stage I), 12 h aeration in P2 (stage II), and 18 h aeration in P2 (stage III). The results showed the possibilities for treating landfill leachate, presenting an average efficiency of 75% for both filtered biochemical oxygen demand and ammonium. At the end of stage III, the ammonium concentration was 6 mg L⁻¹, which is lower than that established by Brazilian regulations for wastewater discharge (CONAMA 430/2011). The aeration applied in P2 led to a change in the microbial consortia during the second and third stage, which influenced the quality of the final effluent. The best performance was seen in stage III, where the system showed high microbial diversity, including the presence of nitrifying bacteria. PMID:25098879

  19. Processing of Oak Ridge B&C pond sludge surrogate in the transportable vitrification system

    SciTech Connect

    Zamecnik, J.R.; Young, S.R.; Peeler, D.K.; Smith, M.E.

    1997-04-16

    The Transportable Vitrification System (TVS) developed at the Savannah River Site is designed to process low-level and mixed radioactive wastes into a stable glass product. The TVS consists of a feed preparation and delivery system, a joule-heated melter, and an offgas treatment system. Surrogate Oak Ridge Reservation (ORR) B&C pond sludge was treated in a demonstration of the TVS system at Clemson University and at ORR. After initial tests with soda-lime-silica (SLS) feed, three melter volumes of glass were produced from the surrogate feed. A forthcoming report will describe glass characterization; and melter feeding, operation, and glass pouring. Melter operations described will include slurry characterization and feeding, factors affecting feed melt rates, glass pouring and pour rate constraints, and melter operating temperatures. Residence time modeling of the melter will also be discussed. Characterization of glass; including composition, predicted liquidity and viscosity, Toxic Characteristic Leaching Procedure (TCLP), and devitrification will be covered. Devitrification was a concern in glass container tests and was found to be mostly dependent on the cooling rate. Crucible tests indicated that melter shutdown with glass containing Fe and Li was also a devitrification concern, so the melter was flushed with SLS glass before cooldown.

  20. Assessing optical earth observation systems for mapping and monitoring temporary ponds in arid areas

    NASA Astrophysics Data System (ADS)

    Soti, Valérie; Tran, Annelise; Bailly, Jean-Stéphane; Puech, Christian; Seen, Danny Lo; Bégué, Agnes

    2009-10-01

    Remote sensing methods for locating and monitoring temporary ponds over large areas in arid lands were tested on a study site in Northern Senegal. Three main results are presented, validated with field data and intended to highlight different spectral, spatial and temporal characteristics of the methods: (1) Among several water indices tested, two Middle Infrared-based indices (MNDWI—Modified Normalized Difference Water Index and NDWI 1—Normalized Difference Water Index) are found to be most efficient; (2) an objective method is given prescribing the necessary sensor spatial resolution in terms of minimal detected pond area; and (3) the potential of multi-temporal MODIS imagery for tracking the filling phases of small ponds is illustrated. These results should assist in epidemiological studies of vector-borne diseases that develop around these ponds, but also more generally for land and water management and preservation of threatened ecosystems in arid areas.

  1. Solar pond seawater heating system for shellfish mariculture. Final progress report

    SciTech Connect

    Kassner, J.

    1984-01-01

    To supplement natural hard clam (Mercenaria mercenaria) production, Brookhaven Township constructed an onland facility to culture seed clasm in 1980. The facility is only operated from June to October when water temperatures are above 60/sup 0/F, the minimum acceptable for hard clam growth. If seawater could be heated economically, operation of the facility could begin in March, thereby increasing hard clam production. The use of solar energy is particularly suited for this purpose since the seawater need only be warmed a few degrees. After considering a number of active and passive type systems, the Town opted for the latter since it would be simpler to build and operate, less expensive, and at the same time would meet the biological requirements of the hard clam. The two basic components of the solar pond, as the system is known, are a reservoir in which the seawater is heated by direct absorption and a transparent cover to minimize heat loss. For an initial production of 1 million .75mm seed clams, two tanks each measuring 10 feet by 20 feet by 3 feet deep were installed beneath a greenhouse type structure. Total cost of the system was less than $23,000.

  2. Polishing of treated palm oil mill effluent (POME) from ponding system by electrocoagulation process.

    PubMed

    Bashir, Mohammed J K; Mau Han, Tham; Jun Wei, Lim; Choon Aun, Ng; Abu Amr, Salem S

    2016-01-01

    As the ponding system used to treat palm oil mill effluent (POME) frequently fails to satisfy the discharge standard in Malaysia, the present study aimed to resolve this problem using an optimized electrocoagulation process. Thus, a central composite design (CCD) module in response surface methodology was employed to optimize the interactions of process variables, namely current density, contact time and initial pH targeted on maximum removal of chemical oxygen demand (COD), colour and turbidity with satisfactory pH of discharge POME. The batch study was initially designed by CCD and statistical models of responses were subsequently derived to indicate the significant terms of interactive process variables. All models were verified by analysis of variance showing model significances with Prob > F < 0.01. The optimum performance was obtained at the current density of 56 mA/cm(2), contact time of 65 min and initial pH of 4.5, rendering complete removal of colour and turbidity with COD removal of 75.4%. The pH of post-treated POME of 7.6 was achieved, which is suitable for direct discharge. These predicted outputs were subsequently confirmed by insignificant standard deviation readings between predicted and actual values. This optimum condition also permitted the simultaneous removal of NH3-N, and various metal ions, signifying the superiority of the electrocoagulation process optimized by CCD. PMID:27232407

  3. Removal of faecal bacteria from septage by treating it in a full-scale duckweed-covered pond system.

    PubMed

    Papadopoulos, Frantzis H; Tsihrintzis, Vassilios A; Zdragas, Antonios G

    2011-12-01

    Performance of a full-scale duckweed-covered treatment system in removing faecal bacteria is presented. The system consisted of three ponds in series and received septage from holding tanks. Inflow averaged between 36 m(3) d(-1) in the cold season and 60 m(3) d(-1) in the warm season, resulting in a total hydraulic retention time of 88 and 58 days, respectively. Duckweed (Lemna minor) colonized the ponds in the summer and continued to grow in the cold season. Due to the difficult harvesting process of the duckweed biomass, the investigation of the treatment efficiency was carried out without plant harvesting. The system was monitored for temperature, pH, oxygen, chlorophyll-a, Escherichia coli and Enterococci. Duckweed growth resulted in chlorophyll-a concentration reduction from 924 to 13 μg L(-1), causing neutral and anoxic conditions in the pond water. A temperature effect was noticed on the E. coli decay coefficient with a decreasing trend along the treatment system. Enterococci always decayed less than E. coli. Differences on decay coefficients and removal efficiencies were not observed between the three ponds for both bacterial types. Effluent quality in terms of E. coli was 489 and 1377 cfu/100 mL, in the warm and the cold seasons, respectively, with average removals of 99.65 ± 1.46% and 99.33 ± 3.03%. Total Enterococci removal was 88.91 ± 23.1% in the warm season and 94.43 ± 24.45% in the cold season, resulting in mean effluent values of 1058 and 1404 cfu/100 mL, respectively. The seasonal differences in total removal efficiencies were insignificant for both bacterial types. PMID:21872385

  4. Comparison of hydraulics and particle removal efficiencies in a mixed cell raceway and Burrows pond rearing system

    USGS Publications Warehouse

    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.

  5. Management and treatment of landfill leachate by a system of constructed wetlands and ponds in Singapore.

    PubMed

    Sim, C H; Quek, B S; Shutes, R B E; Goh, K H

    2013-01-01

    Lorong Halus, Singapore's first landfill leachate treatment system, consists of a pre-treatment system (8,000 m(2)), five constructed reed beds (38,000 m(2)), five polishing ponds (13,000 m(2)), an education centre and a learning trail for visitors. Eight species of wetland plants (total 160,000 plants) were selected for their ability to uptake nutrients, tolerance to low phosphorus concentrations and resistance to pest infestations. The wetland was launched in March 2011 and water quality monitoring started in April 2011. The removal efficiencies of the pre-treatment system from April 2011 to August 2012 are biochemical oxygen demand (BOD5) 57.4%; chemical oxygen demand (COD) 23.6%; total suspended solids (TSS) 55.1%; ammoniacal nitrogen (NH4-N) 76.8%; total phosphorus (TP) 33.3% and total nitrogen (TN) 60.2%. Removal efficiencies of the reed beds are BOD5 47.0%; COD 42.2%; TSS 57.0%; NH4-N 82.5%; TP 29.3% and TN 83.9%. Plant growth is generally satisfactory, but the lower than designed volume of leachate has adversely affected some sections of plants and resulted in uneven flow distribution in reed beds. The plant management programme includes improving plant regrowth by harvesting of alternate strips of plants and replanting. The treated effluent meets water quality limits for discharge to the public sewer and is subsequently treated by the NEWater treatment system, which recycles water for industrial and indirect potable use. PMID:24037164

  6. Performance evaluation of a simple wastewater treatment system comprised by UASB reactor, shallow polishing ponds and coarse rock filter.

    PubMed

    von Sperling, Marcos; Oliveira, Carolina Moreira; Andrada, Juliana G B; Godinho, Valéria M; Assunção, Fernando A L; Junior, Wilson R Melo

    2008-01-01

    The work investigates a small full-scale wastewater treatment system comprised by the following units in series: UASB reactor, three polishing ponds and one coarse rock filter. The overall performance of the system is analyzed based on three years of monitoring using physical-chemical and biological parameters. Good organic matter, suspended solids and ammonia removal is achieved, together with excellent coliform removal (5.70 log units). Mean effluent concentrations of the main parameters are: BOD: 39 mg/L; COD: 109 mg/L; SS = 41 mg/L; ammonia: 10 mg/L; E. coli: 540 MPN/100 mL, indicating compliance with many regulations for effluent discharge and reuse. Main algal classes found in the ponds and final effluent were chlorophyta and euglenophyta. The system is completely unmechanized and has a relatively small total hydraulic retention time (less than 13 days), compared with most natural treatment processes. No sludge removal from the ponds and filter has been necessary so far. PMID:18845872

  7. Recycle as an alternative to algal TSS and BOD removal from an industrial waste stabilization pond system

    SciTech Connect

    Davis, E.M.; Downs, T.D.; Shi, Y.; Ajgaonkar, A.A.

    1996-11-01

    Reuse of wastewater is acquiring a more important role in the overall concept of water conservation management. Information on industrial waste stabilization pond (WSP) effluent recycling or reuse for cooling water purposes is virtually nonexistent. This paper presents data from investigations that were conducted to determine the feasibility of recycling a WSP series effluent back within the system for BOD and total suspended solids (TSS) reduction, which were algal in origin, and separately, to evaluate whether recycling the final WSP effluent to the industry`s cooling water ponds would show corrosion compatibility. The second part of this paper contains data developed form analyses of the settling characteristics of the algal standing crop in the industrial WSPs in question to determine the extent to which autosedimentation could occur.

  8. Lagoons and oxidation ponds. [Wastewater treatment

    SciTech Connect

    George, D.B.

    1982-06-01

    A review of the literature on waste stabilization pond systems is presented. Factors such as wastewater temperature, and levels of heavy metals that affect the stability of the lagoons and oxidation ponds, and methods to upgrade stabilization pond effluent to meet state and federal effluent requirements are discussed. Model simulations utilized to predict the treatment efficiency of various waste stabilization pond geometries, and inlet and outlet configurations are reviewed. (KRM)

  9. Evaluation of the seasonal performance of a water reclamation pond-constructed wetland system for removing emerging contaminants.

    PubMed

    Matamoros, Víctor; Salvadó, Victòria

    2012-01-01

    The capacity of a full-scale reclamation pond-constructed wetland (CW) system to eliminate 27 emerging contaminants (i.e. pharmaceuticals, sunscreen compounds, fragrances, antiseptics, fire retardants, pesticides, and plasticizers) and the seasonal occurrence of these contaminants is studied. The compounds with the highest concentrations in the secondary effluent are diclofenac, caffeine, ketoprofen, and carbamazepine. The results show that the constructed wetland (61%) removes emerging contaminants significantly more efficiently than the pond (51%), presumably due to the presence of plants (Phragmites and Thypa) as well as the higher hydraulic residence time (HRT) in the CW. A greater seasonal trend to the efficient removal of these compounds is observed in the pond than in the CW. The overall mass removal efficiency of each individual compound ranged from 27% to 93% (71% on average), which is comparable to reported data in advanced treatments (photo-fenton and membrane filtration). The seasonal average content of emerging contaminants in the river water (2488 ng L(-1)) next to the water reclamation plant is found to be higher than the content in the final reclaimed water (1490 ng L(-1)), suggesting that the chemical quality of the reclaimed water is better than available surface waters. PMID:22051341

  10. Investigation of sodium carbonate, sodium bicarbonate and water systems for saturated solar ponds. Final report

    SciTech Connect

    1980-03-28

    The overall objective of this study was to gather relevant data primarily from the published literature to investigate the technical feasibility of using a Na/sub 2/CO/sub 3/-NaHCO/sub 3/ mixture for a saturated solar pond. This objective was accomplished by a literature search and review of existing chemical information and by performing simple chemistry experiments in the laboratory. Information on density, solubility, phase diagram, equilibrium compositions, reaction rate constant, equilibrium constant, diffusion coefficient, vapor pressure and potentially useful additives is compiled. It is concluded that even though both the saturation density and solubility increase with temperature for trona, it is not chemically stable either at room temperature or higher temperatures (80/sup 0/C). Therefore, as is, trona is not suitable for use in a saturated solar pond. From the literature it has been found that sugar and gum can retard the decomposition of bicarbonate to carbonate in the mixture. Nevertheless, trona is a very attractive solute for an unsaturated solar pond. A laboratory unsaturated pond with a stable density gradient has worked without any problems for about two months at InterTechnology/Solar Corporation.

  11. Solar pond

    NASA Technical Reports Server (NTRS)

    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.

  12. The spatial and temporal dynamics of carbon dioxide fluxes from a continental Canadian wetland-pond system

    NASA Astrophysics Data System (ADS)

    Schmiedeskamp, Marcel; Blodau, Christian

    2016-04-01

    Due to their high number, small continental ponds are often an important and significant source of methane (CH4) and carbon dioxide (CO2) on the landscape scale. Until now, only little is known about temporal and especially spatial dynamics of carbon fluxes of a temperate wetland-pond system yet. We determined the CO2 fluxes in one of this systems (847 m2) in southern Ontario, Canada, along a high spatial resolution transect of seven sites and high temporal solution (10 min interval) continuously over the complete summer of 2015, using measurement units in closed chamber based on small ELG CO2 loggers (SenseAir), which detect CO2 by non-dispersive infrared (NDIR) spectroscopy, and using one NDIR sensor in a water impermeable, gas permeable membrane deployed under water. All sites showed a net source of CO2 to the atmosphere, but they showed spatial differences in size of fluxes amounting from 16.73 (-14.48 to 124.52) mmol CO2 m‑2 d‑1 to 80.45 (-2.44 to 210.65) mmol CO2 m‑2 d‑1. At all sites the CO2 fluxes decreased significantly in fall, it can be explained by a correlation with radiation and wind. Due to the wind, there is an increased release and stock emptying. The spatial differences are mainly explained by the groundwater dynamics, which have a rising effect on the carbon fluxes. This study shows the large spatial variability of CO2 at the peatland-pond system and the importance of the spatial differences in determination of CO2 fluxes for a complete system, which should not be ignored in order to estimate the correct amount of greenhouse gases to the atmosphere.

  13. Design and analysis of microalgal open pond systems for the purpose of producing fuels: A subcontract report

    SciTech Connect

    Weissman, J.C.; Goebel, R.P.

    1987-04-01

    The designs and systems developed include many innovative concepts and experiments, including the design and operation of a low-cost system. Cost-effectiveness is realized by minimizing capital costs of the system and achieving efficient use of inputs. Extensive engineering analysis of carbonation, mixing, and harvesting subsystems has elucidated both the lowest cost, most efficient options and the essential parameters needed to construct, test, and evaluate these subsystems. The use of growth ponds sealed with clay and lined with crushed rock results in construction cost savings of 50% over ponds lined with synthetic membranes. In addition a low-cost but efficient design allows improvements in technology to have maximum impact on final product cost reductions. In addition to the innovations in low-cost construction, the operational efficiency of the design is both higher and more feasible than that attained by any previous system concept of comparable scale. The water analysis has led to operational specifications that minimize water use and virtually eliminate losses of carbon dioxide to the atmosphere. The carbon dioxide injection system is designed for 95% efficiency, but is still low in cost. The construction of a large-scale, covered anaerobic lagoon to recycle carbon, nitrogen, and phosphorus has not been attempted at the scale analyzed here. Yet efficient recycling is essential for achieving economic affordability. 23 refs., 21 figs., 53 tabs.

  14. Effects of aeration position on organics, nitrogen and phosphorus removal in combined oxidation pond-constructed wetland systems.

    PubMed

    Wang, Xiaoou; Tian, Yimei; Zhao, Xinhua; Peng, Sen; Wu, Qing; Yan, Lijian

    2015-12-01

    Given that few studies investigated the effects of aeration position (AP) on the performance of aerated constructed wetlands, the aim of this study was to evaluate the effects of AP on organics, nitrogen and phosphorus removal in lab-scale combined oxidation pond-constructed wetland (OP-CW) systems. Results showed that middle aeration allowed the CW to possess more uniform oxygen distribution and to achieve greater removals of COD and NH3-N, while the CW under bottom aeration and surface aeration demonstrated more distinct stratification of oxygen distribution and surface aeration brought about better TN removal capacity for the OP-CW system. However, no significant influence of artificial aeration or AP on TP removal was observed. Overall, AP could significantly affect the spatial distribution of dissolved oxygen by influencing the oxygen diffusion paths in aerated CWs, thereby influencing the removal of pollutants, especially organics and nitrogen, which offers a reference for the design of aerated CWs. PMID:26360599

  15. Sport fishery potential of power plant cooling ponds: Final report

    SciTech Connect

    Heidinger, R.C.; Lewis, W.M.

    1986-10-01

    This research was undertaken to determine if cooling ponds could serve as habitat for several coolwater fish species and also to evaluate the potential use of cooling ponds as nursery areas for receiving waters. The work was conducted on two cooling ponds in northern Illinois. Walleye (Stizostedion vitreum), muskellunge (Esox masquinongy), striped bass (Morone saxatilis) fingerlings, and adult threadfin shad (Dorosoma petenense) were stocked into both cooling ponds. The hybrids between the striped bass and white bass (M. chrysops) had been previously stocked into Collins Pond. Smallmouth bass (Micropterus dolomieui) fingerlings and larval striped bass and walleye were stocked in Dresden Pond. Several sampling techniques including seining, electrofishing, and rotenoning were used to monitor growth and survival of stocked species. In addition, escapement of stocked and indigenous species was monitored at the Dresden Pond spillway. Walleye, muskellunge, striped bass and hybrid striped bass exhibited excellent growth in Collins Pond as did smallmouth bass in Dresden Pond. One of the primary differences between an open system (such as Dresden Pond) and a closed system (such as Collins Pond) is the potential that the open system has to serve as a fish nursery area for receiving waters. The stocking of ''coolwater'' species in a closed type system such as Collins Pond is an effective way to control and maintain selected sport species. Dresden Pond was not open to public fishing during this study, but Collins Pond developed an excellent sport fishery as a result of these stockings.

  16. Evaluation of a recirculating pond system for rearing juvenile freshwater mussels at White Sulphur Springs National Fish Hatchery, West Virginia, U.S.A.

    USGS Publications Warehouse

    Mummert, A.; Newcomb, T.J.; Neves, R.J.; Parker, B.

    2006-01-01

    A recirculating double-pond system at White Sulphur Springs National Fish Hatchery in West Virginia, U.S.A., was evaluated for suitability for culturing juvenile freshwater mussels. Newly metamorphosed juveniles of Villosa iris and Lampsilis fasciola were placed in the system, and their growth and survival were evaluated for 94 days. Throughout the study, parameters of water quality remained within ranges suitable for mussel survival. Planktonic algal densities in the pond system ranged from 2850 to 6892 cells/ml. Thirty-seven algal taxa were identified, primarily green algae (Chlorophyta), diatoms (Bacillariophyceae), and blue-green algae (Cyanoprokaryota). Over the culture period, juveniles of L. fasciola experienced significantly lower (p < 0.001) survival (6.3% ?? 4.5) than those of V. iris (49.8% ?? 14.5). The very low survival rate of L. fasciola may indicate a failure of the flow-through pond environment to meet its habitat requirements or that variable microhabitat conditions within culture containers existed. Growth did not differ significantly between the species (p = 0.13). Survival of V. iris and growth of both species were similar to previous trials to culture juvenile mussels. Survival rates as high as 66.4% at 93 days for V. iris suggest that juveniles of some riverine species can be successfully cultured in a recirculating pond environment.

  17. Purification of Solar Ponds

    NASA Technical Reports Server (NTRS)

    Carpenter, S.

    1985-01-01

    Flocculatory agents added to solar saltponds remove turbidity to increase solar-energy collection efficiency. Flocculating agent or bacteriocide used to remove micro-organisms sprayed onto pond from airplane and allowed to settle to bottom of pond.

  18. Waste Stabilization Ponds.

    ERIC Educational Resources Information Center

    Koundakjian, Philip

    This self-paced course contains reading assignments from a waste stabilization ponds operating manual, supportive text, example problems, and review questions, and a final examination. The course covers calculation of pond surface area, pond volume, organic load, detention time, drawdown, storage capacity, efficiency, and discharge. In addition,…

  19. Lagoons and Oxidation Ponds.

    ERIC Educational Resources Information Center

    O'Brien, W. J.

    1978-01-01

    Presents the 1978 literature review of wastewater treatment. This review covers lagoons and oxidation ponds, and it includes some areas such as improving the effluents from ponds, stabilization ponds, aerated lagoons, and oxidation ditches. A list of 36 references is also presented. (HM)

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

    SciTech Connect

    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.

  1. WMOST v2 Case Study: Monponsett Ponds

    EPA Science Inventory

    This webinar presents an overview of the preliminary results of a case study application of EPA's Watershed Management Optimization Support Tool v2 (WMOST) for stakeholders in the Monponsett Ponds Watershed Workgroup. Monponsett Ponds is a large water system consisting of two ba...

  2. Application of solar ponds to district heating and cooling

    NASA Astrophysics Data System (ADS)

    Leboeuf, C. M.

    1981-04-01

    A preliminary investigation is reported of the feasibility of incorporating solar ponds into subdivisions to provide district heating, domestic hot water (DHW), and district cooling. Two locations were chosen for analysis: Fort Worth, Texas and Washington, D.C. Solar ponds were sized to meet space heating, cooling, and DHW loads in each location for differing community sizes. Parameters such as storage layer temperature, pond geometry, and storage depth vs surface area were varied to determine the most effective approach to solar pond utilization. A distribution system for the district heating system was designed, including sizing of heat exchangers, piping, and pumps. Cost estimates for the pond and distribution system were formulated by using data generated in pond sizing, as well as associated system costs (e.g., salt costs and distribution system costs). Finally, solar ponds were found to be competitive with residential flat plate collector systems, with delivered energy costs as low as $16.00/GJ.

  3. Effects of flow speed and circulation interval on water quality and zooplankton in a pond-ditch circulation system.

    PubMed

    Ma, Lin; He, Feng; Sun, Jian; Huang, Tao; Xu, Dong; Zhang, Yi; Wu, Zhenbin

    2015-07-01

    A pond-ditch circulation system (PDCS) shows great promises for ecological restoration of rural contaminated water in southern China. In this study, the optimal flow speed, circulation interval, and their combination for the system were investigated for higher pollutant removal efficiency and lower costs in three separate experiments: I, II, and III, respectively. In each experiment, there are three PDCSs (S1, S2, and S3) with different water circulation speeds or circulation intervals, respectively. The results demonstrated that in experiment I, total nitrogen (TN) removal rates, species numbers, and diversity indexes of zooplankton in S1 with a flow speed of 3.6 L/h were significantly higher than those in S2 (7.2 L/h) and S3 (10.2 L/h), respectively. Similarly, in experiment II, S3 circulating every other 4 h had significantly higher TN reduction rates, species numbers, and diversity indexes than S1 and S2 circulating every other 1 and 2 h, respectively. In experiment III, water qualities in S1 (circulation of 3.6 L/h + interval of 4 h) were better than those in S2 (7.2 L/h + 4 h) and S3 (10.2 L/h + 6 h), respectively. Together, circulation at every other 4 h (3.6 L/h) is probably the optimal operating condition for the PDCS in remediating rural contaminated water. PMID:25693828

  4. Design manual: municipal wastewater stabilization ponds

    SciTech Connect

    Middlebrooks, E.J.; Reynolds, J.H.; Montgomery, J.M.; Middlebrooks, C.; Schneiter, R.W.

    1983-10-01

    The manual provides a concise overview of wastewater stabilization pond systems through discussion of factors affecting treatment, process design principles and applications, aspects of physical design and construction, suspended solids removal alternatives, and cost and energy requirements.

  5. DESIGN MANUAL: MUNICIPAL WASTEWATER STABILIZATION PONDS

    EPA Science Inventory

    The manual provides a concise overview of wastewater stabilization pond systems through discussion of factors affecting treatment, process design principles and applications, aspects of physical design and construction, suspended solids removal alternatives, and cost and energy r...

  6. An evaluation of duckweed-based pond systems as an alternative option for decentralised treatment and reuse of wastewater in Zimbabwe.

    PubMed

    Nhapi, I; Dalu, J; Ndamba, J; Siebel, M A; Gijzen, H J

    2003-01-01

    A study was carried out in Zimbabwe to evaluate the performance of duckweed ponds as an option for treating and reusing wastewater in small, decentralised communities. The study focused on nitrogen and phosphorus removal, operational problems, and duckweed application. Two full-scale trial plants at Nemanwa and Gutu-Mupandawana growth points were used. Sewage samples were collected and analysed monthly from September 2000 to August 2001 for NO3, NH4(-)1 TKN, TP, COD, and other field measurements. The duckweed was harvested daily and fed to chickens. The Nemanwa plant had high nutrient levels due to nil outflows caused by water rationing in the area. The Gutu effluent had averages of 38.7 +/- 23.1 mg/l TN and 7.5 +/- 2.4 mg/l TP which are above the respective Zimbabwean standards of 10 mg/l TN and 1 mg/l TP. COD removal efficiency at Gutu was poor at 45%. The performance of Gutu and Nemanwa plants suffered from inappropriate design especially pond depth and short-circuiting. The duckweed died off in the November-January period, this being attributed to excessive levels of ammonia. It was concluded that the duckweed pond systems would offer a good alternative for managing and reusing wastewater at community level provided due regard is paid to appropriate design criteria. PMID:14510227

  7. Indoor Pond Biology

    ERIC Educational Resources Information Center

    Kunkel, Erika R.

    1977-01-01

    This year-long science program involved fifth grade students in the investigation of a meadow pond. Two field trips to collect pond water and organisms were arranged for the beginning and conclusion of the program. Classroom activities were designed to study aquatic organisms, life cycles, populations, and ecosystems. (MA)

  8. Ripples in a pond: an open system model of the evolution of safety culture.

    PubMed

    Morley, F J Joel; Harris, Don

    2006-01-01

    The development of an effective safety culture is essential to promote safe operations. Previous studies have either identified the characteristics of effective safety culture analytically, inferring them from signs and symbols derived from working practices, or have restricted the study of the development of safety culture to workers within an organisation. This paper describes a large-scale survey-based study in which the factors influencing the evolution of safety culture are identified empirically and, drawing upon open systems theory, are also extended beyond the bounds of the organisation. Three major determinants of safety culture are identified: safety concerns, influences and actions. Sub-components within each of these categories are also identified and the relationship between them is hypothesised. PMID:16553996

  9. Technical manual for calculating cooling pond performance

    SciTech Connect

    Krstulovich, S.F.

    1988-07-01

    This manual is produced in response to a growing number of requests for a technical aid to explain methods for simulating cooling pond performance. As such, it is a compilation of reports, charts and graphs developed through the years for use in analyzing situations. Section II contains a report summarizing the factors affecting cooling pond performance and lists statistical parameters used in developing performance simulations. Section III contains the graphs of simulated cooling pond performance on an hourly basis for various combinations of criteria (wind, solar, depth, air temperature and humidity) developed from the report in Section II. Section IV contains correspondence describing how to develop further data from the graphs in Section III, as well as mathematical models for the system of performance calculation. Section V contains the formulas used to simulate cooling pond performances in a cascade arrangement, such as the Fermilab Main Ring ponds. Section VI contains the calculations currently in use to evaluate the Main Ring pond performance based on current flows and Watts loadings. Section VII contains the overall site drawing of the Main Ring cooling ponds with thermal analysis and physical data.

  10. Tracing source, mixing and uptaking processes of carbon in an epikarst spring-pond system in southeastern Guizhou of China by carbon isotopes (13C-14C)

    NASA Astrophysics Data System (ADS)

    Zhao, M.; Chen, B.; Liu, Z.; Li, H. C.; Yang, R.

    2015-12-01

    δ13C and Δ14C of dissolved inorganic carbon (DIC), particulate organic carbon (POC) and aquatic plants from a karst spring and two spring-fed ponds in Laqiao, Maolan County, Guizhou Province in January, July and October of 2013 were measured to understand the roles of aquatic photosynthesis through DIC uptake in karst surface waters. The mean Δ14C and δ13C values of DIC for the spring pool, midstream and downstream ponds are -60.6±26.3‰ and -13.53±1.97‰, -62.8±62.9‰ and -11.72±2.72‰, and -54.2±56.5‰ and -9.40±2.03‰, respectively. Both Δ14C and δ13C show seasonal variations, with lower Δ14C values but heavier δ13C values in dry season and vice versa in summer rainy season. This observation indicates that (1) the main carbon source of the spring DIC is from limestone bedrock dissolution and soil CO2 with higher contribution in summer due to higher productivity; and (2) 13C and 14C have different behaviors during DIC uptake by aquatic plants and during CO2 exchange between DIC and the atmospheric CO2. Biological uptake of CO2 will not affect the Δ14C of DIC, but lead to δ13CDIC enrichment. CO2 exchange between DIC and the atmospheric CO2 should elevate both the Δ14C and δ13C of DIC. In Laqiao spring-pond system, it seems that the effect of biological uptake on the Δ14C and δ13C of DIC is much stronger than that of CO2 exchange with the atmosphere. The mean Δ14C values of POC from the spring pool, midstream and downstream ponds are -308.1 ±64.3‰, -164.4±84.4‰ and -195.1±108.5‰, respectively, indicating mixture of aquatic algae and detrital particle (clay and dust). More aquatic algae were formed in the stream ponds especially in the summer. SEM results of the POC samples support this conclusion. Furthermore, the Δ14C values of the submerged aquatic plants range from -200.0‰ to -51.3 ‰ and were similar to those of the DIC, indicating that the aquatic plants used DIC for photosynthesis. The Δ14C value of an emergent plant

  11. Exploring Pond Water

    ERIC Educational Resources Information Center

    Raun, Chester E.; Metz, William C.

    1975-01-01

    An activity utilizing a bucket of pond water for study of microorganisms as presented to elementary school preservice and inservice teachers, and subsequently to their pupils, is described. Procedures for collecting, studying, tabulating data and extended activities are presented. (EB)

  12. Cannibalism in single-batch hybrid catfish production ponds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  13. Treatment of piggery wastes in waste stabilization ponds.

    PubMed

    Estrada, V E E; Hernández, D E A

    2002-01-01

    The piggery industry produces high effluent loads. This is due to the high concentration of animals kept in a confined space, foods with high protein content that are not well assimilated by the animals, and poor on-farm water management. In this study, we present the characteristics, design, site selection, soil study, and the construction of a pilot pond system for a family farm located in a warm climate area. The design includes a solids sedimentation phase, an anaerobic pond, a facultative pond and three maturation ponds. Once the system had reached steady state, the organic and bacterial kinetic constants were determined for each pond. The control parameters were determined and the dissolved oxygen and removal efficiency profiles were obtained. The results indicate that the effluent from the second maturation pond complies with the Official Mexican Standard for reuse in agriculture ("1000 FC/100 ml). PMID:11841058

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

    PubMed

    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. PMID:23490108

  15. Falmouth pond watchers: Water quality monitoring of Falmouth's coastal ponds. Report from the 1992 season

    SciTech Connect

    Howes, B.L.; Goehringer, D.D.

    1993-04-01

    1992 has seen a significant expansion in the focus of the Pond Watchers program. The long-term, high quality data base for the ponds is now enabling more emphasis on the ecological management and remediation aspects of the study, the ultimate goal of the program. Overall, 1992 saw only slight variation in the water quality conditions of Oyster, Little, Green, Great and Bournes Ponds from previous years, with a declining trend for Green Pond and small improvements in lower Great and Bournes Ponds. However, Oyster Pond showed a potentially significant improvement in bottom water oxygen conditions which suggests a new management direction for this system. All of the ponds continue to exhibit high nutrient levels and periodic bottom water oxygen depletion, especially in their upper reaches, and all stations exceed the nutrient levels specified by the Nutrient Overlay Bylaw. In contrast, the first year measurements in West Falmouth Harbor indicate high levels of water quality, although the inner reaches of the harbor do exceed those levels specified by the Bylaw.

  16. About the interest of a zooplankton compartment in pond systems: methodology to study the growth kinetic of Daphnia pulex on Scenedesmus sp.

    PubMed

    Liady, M N D; Tangou, T T; Fiogbe, E D; Cauchie, H-M; Vasel, J-L

    2015-01-01

    A reliable characterization of cladocerans' growth kinetic on their substrates is crucial for the estimation of their biochemical conversion rate in pond models. Although many studies reported cladocerans' growth inhibitions by high chlorophyceae contents, their growth kinetics had continued to be described in many pond system models by Monod-type kinetic, which describes growth saturation by high substrate contents, but fails to explain the disappearance of cladocerans observed during chlorophyceae's bloom periods. This study aimed to develop a methodology and assess whether growth-inhibition-type models used to describe microbial growth kinetics can be applicable to cladocerans. Experiments were carried out using Daphnia pulex populations and Scenedesmus sp. First, biomass of D. pulex was measured through digital image processing (DIP) during growth experiments. Then, three candidate models (i.e., Andrews, Edward and Haldane models), along with the Monod model, were fitted to the observed data and compared. The results showed that the DIP technique provided reliable results for estimating the biomass of D. pulex. Our findings show that the candidate growth inhibition-type models satisfactorily described D. pulex's growth kinetic (86% variance accounted for). Scenesdemus sp. were not strong inhibitors of the growth of D. pulex (high inhibition constant and low half-saturation constant found). PMID:26442483

  17. Saltless solar pond

    NASA Technical Reports Server (NTRS)

    Lin, E. I. H. (Inventor)

    1984-01-01

    A solar pond adapted for efficiently trapping and storing radiant solar energy without the use of a salt concentration gradient in the pond is disclosed. A body of water which may be fresh, saline, relatively clear or turbid, is substantially covered by a plurality of floating honeycomb panels. The honeycomb panels are made of a material such as glass which is pervious to short wave solar radiation but impervious to infrared radiation. Each honeycomb panel includes a multitude of honeycomb cells. The honeycomb panels are divided into the elongated honeycomb cells by a multitude of intermediate plates disposed between a bottom plate and top plate of the panel. The solar pond is well suited for providing hot water of approximately 85 to 90 C temperature for direct heating applications, and for electrical power generation.

  18. Assimilative capabilities of retention ponds. Final report

    SciTech Connect

    Martin, E.H.; Smoot, J.L.

    1986-04-01

    The efficiency of a detention-pond and wetlands temporary storage system to reduce constituents loads in urban runoff was determined. The reduction efficiencies for 22 constituents, including the dissolved, suspended, and total phases of many of the constituents were investigated. A new method not previously discussed in technical literature was developed to determine the efficiency of a temporary storage-system unit such as a detention pond or wetlands. The method provides an efficiency, called the regression efficiency, determined by a regression made of loads-in against loads-out of a unit with the intercept of the regression constrained to zero. The regression efficiency of the treatment unit is defined as unity minus the regression slope. The system (pond and wetlands) achieved appreciable reductions of loads for most constituents.

  19. Agricultural ponds support amphibian populations

    USGS Publications Warehouse

    Knutson, M.G.; Richardson, W.B.; Reineke, D.M.; Gray, B.R.; Parmelee, J.R.; Weick, S.E.

    2004-01-01

    In some agricultural regions, natural wetlands are scarce, and constructed agricultural ponds may represent important alternative breeding habitats for amphibians. Properly managed, these agricultural ponds may effectively increase the total amount of breeding habitat and help to sustain populations. We studied small, constructed agricultural ponds in southeastern Minnesota to assess their value as amphibian breeding sites. Our study examined habitat factors associated with amphibian reproduction at two spatial scales: the pond and the landscape surrounding the pond. We found that small agricultural ponds in southeastern Minnesota provided breeding habitat for at least 10 species of amphibians. Species richness and multispecies reproductive success were more closely associated with characteristics of the pond (water quality, vegetation, and predators) compared with characteristics of the surrounding landscape, but individual species were associated with both pond and landscape variables. Ponds surrounded by row crops had similar species richness and reproductive success compared with natural wetlands and ponds surrounded by nongrazed pasture. Ponds used for watering livestock had elevated concentrations of phosphorus, higher turbidity, and a trend toward reduced amphibian reproductive success. Species richness was highest in small ponds, ponds with lower total nitrogen concentrations, tiger salamanders (Ambystoma tigrinum) present, and lacking fish. Multispecies reproductive success was best in ponds with lower total nitrogen concentrations, less emergent vegetation, and lacking fish. Habitat factors associated with higher reproductive success varied among individual species. We conclude that small, constructed farm ponds, properly managed, may help sustain amphibian populations in landscapes where natural wetland habitat is rare. We recommend management actions such as limiting livestock access to the pond to improve water quality, reducing nitrogen input, and

  20. Pumping performance of a slow-rotating paddlewheel for split-ponds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Commercial catfish farmers are intensifying production by retrofitting ponds with variations of the partitioned aquaculture system. The split-pond system is the most common variation used commercially. The split-pond consists of a small fish-holding basin connected to a waste treatment lagoon by two...

  1. Minimizing contamination hazards to waterbirds using agricultural drainage evaporation ponds

    NASA Astrophysics Data System (ADS)

    Bradford, David F.; Smith, Lynda A.; Drezner, Deborah S.; Shoemaker, J. David

    1991-11-01

    In much of the San Joaquin Valley, California, USA, inadequate drainage of applied irrigation water and accumulating salts in the soil have necessitated the installation of subsurface tile drainage systems to preserve crop productivity. At present, these subsurface drainage waters are disposed of by means of evaporation ponds or discharges into the San Joaquin River. Unfortunately, most of these agricultural drainage waters contain high concentrations of salts and naturally occurring trace elements, such as selenium, and recent evidence indicates that substantial numbers of waterbirds are exposed to contamination by selenium in the evaporation ponds. In order to avoid, minimize, or mitigate the adverse impacts on wildlife using the ponds, alternative pond management methods must be identified and evaluated for implementation. A number of methods have the potential to be cost-effective in significantly reducing the contamination hazard to birds using agricultural evaporation ponds. Twenty general methods were evaluated in this study, and four methods are recommended for implementation: remove levee vegetation, remove windbreaks, deepen the ponds, and haze birds. A number of other methods are recommended for further consideration because they appear to have good prospects for reducing the contamination hazard: steepen interior levee slopes, apply herbicides and insecticides, place netting on pond shorelines, and provide freshwater habitat adjacent to evaporation ponds. It may be necessary to use a combination of methods to effectively control selenium contamination of aquatic birds because it is unlikely that a single affordable pond management method will be able to entirely eliminate the contamination hazard.

  2. Review of the current status of reverse electrodialysis systems for salinity power systems using a stratified saturated solar pond. Final report. Report No. 220280

    SciTech Connect

    Not Available

    1980-02-22

    The overall objective of this study was to develop and place in operation a small salinity power heat engine of 100-watt capacity consisting of a saturated solar pond (SSP) coupled to a reverse electrodialysis (RED) membrane stack. The objectives of the contract were: (1) to demonstrate that a SSP can be used for unmixing of a mixed brine into a dilute and a concentrated brine stream, (2) to demonstrate that a RED stack can generate electrical power, and (3) to generate the necessary experimental data on the RED-SSP system which can be used to assess the potential of such a system for economical energy generation. The results of findings on the current status of ion-exchange membranes and RED stacks is summarized. It is shown that the electrical resistance of the present-day membranes, which are produced for electrodialysis and not reverse electrodialysis, and the solution compartments are very high. This causes the power density of present-day RED stacks, in terms of watts per unit membrane area, to be very low. This factor combined with the high cost of present-day membranes results in very high costs for the RED stack. Furthermore, present-day membranes as well as adhesives for membrane assemblies cannot operate at about 80/sup 0/C for any reasonable length of time without severe deterioration in performance. The areas that require development work include: (1) development of cheap ion-exchange membranes with low electrical resistance and high permselectivity; (2) development of very thin solution compartments; (3) development of RED stacks which can operate at high temperatures; and (4) laboratory testing of small RED stacks to investigate the effect of temperature on stack performance and the fouling of RED membranes with time, have been identified. (WHK)

  3. The Little School Pond

    ERIC Educational Resources Information Center

    Rawitscher-Kunkel, Erika

    1973-01-01

    A small pond in a schoolyard provided year-round biological activities for children. As seasons changed, concepts and life relations also changed. Besides microscopic organisms in water, children learned about microscopic algae, detritus, and food chains. Concepts of predator-prey relationships and of ecosystems were successfully developed. (PS)

  4. Let's Build a Pond!

    ERIC Educational Resources Information Center

    Winkeljohn, Dorothy R.; Earl, Robert D.

    1982-01-01

    Describes a game for grades three-six designed to demonstrate the interdependence between living things and the physical factors of their environment. Although instructions (including preparing game cards) are provided related to a pond, the game adapts to other environments such as a field, woodland, or desert. (Author/JN)

  5. Heat extraction from a large solar pond

    SciTech Connect

    Wittenberg, L.J.; Etter, D.E.

    1982-01-01

    The largest operational, salt-gradient solar pond in the United States, occupying 2000 m/sup 2/, was constructed during 1978 in Miamisburg, Ohio. The heat from this solar pond, nearly 1055 GJ/yr (1,000 million Btu/yr) is used to heat an outdoor swimming pool in the summer and an adjacent recreation building during part of the winter. A new heat exchanger system has been installed externally to the pond and operated successfully to deliver 391 GJ (371 million BTU) of heat during May-June. Hot brine water is drawn through a diffuser by a self-priming pump fabricated from fiberglass reinforced plastic. The brine water passes through copper-10% nickel tubes of a tube-and-shell heat exchanger and is then returned to the bottom of the pond. Cooling water from the swimming pool circulates through the shell side of the heat exchanger. Several designs and flow velocities of the brine inlet and outlet diffusers into the pond have been tested in order to minimize the effect of turbulence upon the salt gradient zone.

  6. Heat extraction from a large solar pond

    SciTech Connect

    Wittenberg, L.J.; Etter, D.E.

    1982-08-01

    The largest operational, salt-gradient solar pond in the United States, occupying 2000 m/sup 2/, was constructed during 1978 in Miamisburg, Ohio. The heat from this solar pond, nearly 1055 GJ/y (1000 million Btu/y) is used to heat an outdoor swimming pool in the summer and an adjacent recreation building during part of the winter. A new heat exchanger system has been installed externally to the pond and operated successfully to deliver 391 GJ (371 million Btu) of heat during May-June. Hot brine water is drawn through a diffuser by a self-priming pump fabricated from fiberglass reinforced plastic. The brine water passes through copper-10% nickel tubes of a tube-and-shell heat exchanger and is then returned to the bottom of the pond. Cooling water from the swimming pool circulates through the shell side of the heat exchanger. Several designs and flow velocities of the brine inlet and outlet diffusers into the pond have been tested in order to minimize the effect of turbulence upon the salt gradient zone.

  7. Evaluation of solar pond performance

    SciTech Connect

    Wittenberg, L.J.

    1981-01-01

    During 1978 the City of Miamisburg constructed a large, salt-gradient solar pond as part of its community park development project. The thermal energy stored in the pond is being used to heat an outdoor swimming pool in the summer and an adjacent recreational building during part of the winter. This solar pond, which occupies an area of 2020 m/sup 2/ (22,000 ft/sup 2/), was designed from experience obtained at smaller research ponds. This project is directed toward data collection and evaluation of the thermal performance and operational characteristics of the largest, operational, salt-gradient solar pond in the United States; to gain firsthand experience regarding the maintenance, adjustments and repairs required of a large, operational solar pond facility; and to provide technical consulation regarding the operation and the optimization of the pond performance.

  8. Potential land competition between open-pond microalgae production and terrestrial dedicated feedstock supply systems in the U.S.

    DOE PAGESBeta

    Coleman, Andre M.; Wigmosta, Mark S.; Hellwinckel, Chad M.; Brandt, Craig C.; Langholtz, Matthew H.; Eaton, Laurence M.

    2016-03-03

    To date, feedstock resource assessments have evaluated cellulosic and algal feedstocks independently, without consideration of demands for, and resource allocation to, each other. We assess potential land competition between algal and terrestrial feedstocks in the United States, and evaluate a scenario in which 41.5 × 109 L yr–1 of second-generation biofuels are produced on pastureland, the most likely land base where both feedstock types may be deployed. Under this scenario, open-pond microalgae production is projected to use 1.2 × 106 ha of private pastureland, while terrestrial biomass feedstocks would use 14.0 × 106 ha of private pastureland. A spatial meta-analysismore » indicates that potential competition for land under this scenario would be concentrated in 110 counties, containing 1.0 and 1.7 × 106 ha of algal and terrestrial dedicated feedstock production, respectively. Furthermore, a land competition index applied to these 110 counties suggests that 38 to 59 counties could experience competition for upwards of 40% of a county's pastureland, representing 2%–5% of total pastureland in the U.S.; therefore suggesting little overall competition between algae production, terrestrial energy feedstocks and alternative uses for existing agricultural production such as livestock grazing.« less

  9. Management of a large, operational solar pond

    SciTech Connect

    Wittenberg, L.J.; Harris, M.J.

    1980-01-01

    Routine and non-routine maintenance are discussed based upon experience during the past two years at the largest operational solar pond in the United States. Routine maintenance of a solar pond, such as algae control and water clarity control, is minimal and the upkeep expense associated with this maintenance is small. Non-routine maintenance, however, can be very involved, as well as expensive. Although non-routine maintenance can consist of various problems which may arise in a pond, this paper deals only with corrosion of the heat exchanger and a leak in the containment system. With proper planning and preventive measures, even those difficult problems can be controlled and satisfactory repairs made.

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

    USGS Publications Warehouse

    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.

  11. Design and fish culture considerations for catfish farming in split ponds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Split ponds are simple, pond-based aquaculture systems constructed by dividing an existing catfish pond into two unequal basins with an earthen levee. Fish are confined in the smaller basin (usually about 15-20% of total water area) while the larger basin serves as a waste-treatment lagoon. A high-v...

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

    PubMed

    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

  13. Environmental inactivation of Cryptosporidium parvum oocysts in waste stabilization ponds.

    PubMed

    Reinoso, Roberto; Bécares, Eloy

    2008-11-01

    The survival of Cryptosporidium parvum oocysts in a waste stabilization pond system in northwestern Spain and the effects of sunlight and the depth and type of pond on oocyst viability were evaluated using an assay based on the exclusion or inclusion of two fluorogenic vital dyes, 4',6-diamidino-2-phenylindole (DAPI) and propidium iodide (PI). All tested factors had significant effects (P < 0.01) over time on C. parvum oocyst viability. Sunlight exposure was the most influential factor for oocyst inactivation. A 40% reduction was observed after 4 days exposure to sunlight conditions compared with dark conditions. The type of pond also caused a significant reduction in C. parvum oocyst viability (P < 0.01). Inactivation rates reflected that the facultative pond was the most aggressive environment for oocysts placed both at the surface (presence of sunlight) and at the bottom (absence of sunlight) of the pond, followed by the maturation pond and the anaerobic pond. The mean inactivation rates of oocysts in the ponds ranged from 0.0159 to 0.3025 day(-1). PMID:18345476

  14. A theoretical study of a direct contact membrane distillation system coupled to a salt-gradient solar pond for terminal lakes reclamation.

    PubMed

    Suárez, Francisco; Tyler, Scott W; Childress, Amy E

    2010-08-01

    Terminal lakes are water bodies that are located in closed watersheds with the only output of water occurring through evaporation or infiltration. The majority of these lakes, which are commonly located in the desert and influenced by human activities, are increasing in salinity. Treatment options are limited, due to energy costs, and many of these lakes provide an excellent opportunity to test solar-powered desalination systems. This paper theoretically investigates utilization of direct contact membrane distillation (DCMD) coupled to a salt-gradient solar pond (SGSP) for sustainable freshwater production at terminal lakes. A model for heat and mass transport in the DCMD module and a thermal model for an SGSP were developed and coupled to evaluate the feasibility of freshwater production. The construction of an SGSP outside and inside of a terminal lake was studied. As results showed that freshwater flows are on the same order of magnitude as evaporation, these systems will only be successful if the SGSP is constructed inside the terminal lake so that there is little or no net increase in surface area. For the study site of this investigation, water production on the order of 2.7 x 10(-3) m(3) d(-1) per m(2) of SGSP is possible. The major advantages of this system are that renewable thermal energy is used so that little electrical energy is required, the coupled system requires low maintenance, and the terminal lake provides a source of salts to create the stratification in the SGSP. PMID:20579682

  15. Microalgal separation from high-rate ponds

    SciTech Connect

    Nurdogan, Y.

    1988-01-01

    High rate ponding (HRP) processes are playing an increasing role in the treatment of organic wastewaters in sunbelt communities. Photosynthetic oxygenation by algae has proved to cost only one-seventh as much as mechanical aeration for activated sludge systems. During this study, an advanced HRP, which produces an effluent equivalent to tertiary treatment has been studied. It emphasizes not only waste oxidation but also algal separation and nutrient removal. This new system is herein called advanced tertiary high rate ponding (ATHRP). Phosphorus removal in HRP systems is normally low because algal uptake of phosphorus is about one percent of their 200-300 mg/L dry weights. Precipitation of calcium phosphates by autofluocculation also occurs in HRP at high pH levels, but it is generally not complete due to insufficient calcium concentration in the pond. In the case of Richmond where the studies were conducted, the sewage is very low in calcium. Therefore, enhancement of natural autoflocculation was studied by adding small amounts of lime to the pond. Through this simple procedure phosphorus and nitrogen removals were virtually complete justifying the terminology ATHRP.

  16. Microbiology of solar salt ponds

    NASA Technical Reports Server (NTRS)

    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.

  17. Design of an integrated piggery system with recycled water, biomass production and water purification by vermiculture, macrophyte ponds and constructed wetlands.

    PubMed

    Morand, Philippe; Robin, Paul; Pourcher, Anne-Marie; Oudart, Didier; Fievet, Sebastien; Luth, Daniel; Cluzeau, Daniel; Picot, Bernadette; Landrain, Brigitte

    2011-01-01

    Since 2001 the swine experimental station of Guernévez has studied biological treatment plants for nutrient recovery and water recycling, suited to the fresh liquid manure coming out of flushing systems. An integrated system with continuous recycling was set up in 2007, associated with a piggery of 30 pregnant sows. It includes a screen, a vermifilter, and macrophyte ponds alternating with constructed wetlands. The screen and the vermifilter had a lower removal efficiency than in previous studies on finishing pigs. A settling tank was then added between the vermifilter and the first lagoon to collect the worm casts. A second vermifilter was added to recover this particulate organic matter. A storage lagoon was added to compensate for evaporative losses and complete pollution abatement, with goldfish as a bioindicator of water quality. The removal efficiency of the whole system was over 90% for COD and nitrogen, over 70% for phosphorus and potassium, and more than 4 logarithmic units for pathogens (E. coli, enterococci, C perfringens). Plant production was about 20 T DM ha(-1) y(-1). Floating macrophytes (Azolla caroliniana, Eichhornia crassipes, Hydrocotyle vulgaris) were more concentrated in nutrients than helophytes (Phragmites australis, Glyceria aquatica,…). Azolla caroliniana was successfully added to feed finishing pigs. PMID:21436573

  18. Pond fractals in a tidal flat

    NASA Astrophysics Data System (ADS)

    Cael, B. B.; Lambert, Bennett; Bisson, Kelsey

    2015-11-01

    Studies over the past decade have reported power-law distributions for the areas of terrestrial lakes and Arctic melt ponds, as well as fractal relationships between their areas and coastlines. Here we report similar fractal structure of ponds in a tidal flat, thereby extending the spatial and temporal scales on which such phenomena have been observed in geophysical systems. Images taken during low tide of a tidal flat in Damariscotta, Maine, reveal a well-resolved power-law distribution of pond sizes over three orders of magnitude with a consistent fractal area-perimeter relationship. The data are consistent with the predictions of percolation theory for unscreened perimeters and scale-free cluster size distributions and are robust to alterations of the image processing procedure. The small spatial and temporal scales of these data suggest this easily observable system may serve as a useful model for investigating the evolution of pond geometries, while emphasizing the generality of fractal behavior in geophysical surfaces.

  19. Pond fractals in a tidal flat.

    PubMed

    Cael, B B; Lambert, Bennett; Bisson, Kelsey

    2015-11-01

    Studies over the past decade have reported power-law distributions for the areas of terrestrial lakes and Arctic melt ponds, as well as fractal relationships between their areas and coastlines. Here we report similar fractal structure of ponds in a tidal flat, thereby extending the spatial and temporal scales on which such phenomena have been observed in geophysical systems. Images taken during low tide of a tidal flat in Damariscotta, Maine, reveal a well-resolved power-law distribution of pond sizes over three orders of magnitude with a consistent fractal area-perimeter relationship. The data are consistent with the predictions of percolation theory for unscreened perimeters and scale-free cluster size distributions and are robust to alterations of the image processing procedure. The small spatial and temporal scales of these data suggest this easily observable system may serve as a useful model for investigating the evolution of pond geometries, while emphasizing the generality of fractal behavior in geophysical surfaces. PMID:26651668

  20. [Task 1.] Biodenitrification of low nitrate solar pond waters using sequencing batch reactors. [Task 2.] Solidification/stabilization of high strength and biodenitrified heavy metal sludges with a Portland cement/flyash system

    SciTech Connect

    Figueroa, L.; Cook, N.E.; Siegrist, R.L.; Mosher, J.; Terry, S.; Canonico, S.

    1995-09-22

    Process wastewater and sludges were accumulated on site in solar evaporation ponds during operations at the Department of Energy's Rocky Flats Plant (DOE/RF). Because of the extensive use of nitric acid in the processing of actinide metals, the process wastewater has high concentrations of nitrate. Solar pond waters at DOE/RF contain 300-60,000 mg NO{sub 3}{sup {minus}}/L. Additionally, the pond waters contain varying concentrations of many other aqueous constituents, including heavy metals, alkali salts, carbonates, and low level radioactivity. Solids, both from chemical precipitation and soil material deposition, are also present. Options for ultimate disposal of the pond waters are currently being evaluated and include stabilization and solidification (S/S) by cementation. Removal of nitrates can enhance a wastes amenability to S/S, or can be a unit operation in another treatment scheme. Nitrate removal is also a concern for other sources of pollution at DOE/RF, including contaminated groundwater collected by interceptor trench systems. Finally, nitrate pollution is a problem at many other DOE facilities where actinide metals were processed. The primary objective of this investigation was to optimize biological denitrification of solar pond waters with nitrate concentrations of 300--2,100 mg NO{sub 3}{sup {minus}}/L to below the drinking water standard of 45 mg NO{sub 3}{sup {minus}}/L (10 mg N/L). The effect of pH upon process stability and denitrification rate was determined. In addition, the effect Cr(VI) on denitrification and fate of Cr(VI) in the presence of denitrifying bacteria was evaluated.

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

    NASA Astrophysics Data System (ADS)

    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.

  2. METAPOPULATION STRUCTURE AND DYNAMICS OF POND BREEDING

    EPA Science Inventory

    Our review indicates that pond breeding amphibians exhibit highly variable spatial and temporal population dynamics, such that no single generalized model can realistically describe these animals. We propose that consideration of breeding pond permanence, and adaptations to pond ...

  3. Oxygen and nitrogen dynamics in split ponds vs. conventional catfish production ponds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Split Pond aquaculture system (SP) has captured the attention of catfish producers across the southern U.S. The SP represents a lower cost adaptation of Clemson University’s Partitioned Aquaculture System (PAS). The original PAS design relied on slowly rotating paddlewheels to move water throu...

  4. Oxygen and nitrogen dyamics in split ponds vs. intensive and conventional catfish production ponds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Split Pond aquaculture system (SP) has captured the attention of catfish producers across the southern U.S. The SP represents a lower cost adaptation of Clemson University’s Partitioned Aquaculture System (PAS). The original PAS design relied on slowly rotating paddlewheels to move water throu...

  5. One-dimensional transient finite difference model of an operational salinity gradient solar pond

    NASA Technical Reports Server (NTRS)

    Hicks, Michael C.; Golding, Peter

    1992-01-01

    This paper describes the modeling approach used to simulate the transient behavior of a salinity gradient solar pond. A system of finite difference equations are used to generate the time dependent temperature and salinity profiles within the pond. The stability of the pond, as determined by the capacity of the resulting salinity profile to suppress thermal convection within the primary gradient region of the pond, is continually monitored and when necessary adjustments are made to the thickness of the gradient zone. Results of the model are then compared to measurements taken during two representative seasonal periods at the University of Texas at El Paso's (UTEP's) research solar pond.

  6. New England Lakes & Ponds Project

    EPA Science Inventory

    The New England Lakes and Ponds Project provides a consistent and first time comprehensive assessment of the ecological and water quality condition of lakes and ponds across the New England region. The project is being conducted by EPA along with the New England Interstate Water...

  7. Schoolyard Ponds: Safety and Liability.

    ERIC Educational Resources Information Center

    Danks, Sharon Gamson

    2001-01-01

    Engaging, attractive schoolyard ponds provide habitat for wildlife and hold great educational promise. Reviews water safety and liability issues including mud, stagnant pond water that serves as mosquito breeding grounds, and drowning. Offers ideas for creatively addressing those issues through site planning, shallow water depth, signage and…

  8. The Pond Is Our Laboratory

    ERIC Educational Resources Information Center

    Marchewka, Barbara Turco

    1978-01-01

    This science teacher's laboratory is a pond within walking distance of his school that provides a stimulating environment for exploring the natural world. With simple materials students practice making careful observations, taking measurements and compiling and graphing information for their science studies. They also extend their pond experiences…

  9. Further contributions to nitrogen removal modelling in waste stabilization ponds.

    PubMed

    Bastos, R K X; Cabral, V A L; Rios, E N; Combatt, M P M

    2014-01-01

    A large database from an experimental maturation pond system in Brazil was used to verify the agreement of field results with values predicted by some of the most widely accepted models to describe ammonium and total nitrogen (TN) removal in facultative and maturation ponds. The same database was used to derive a pH-independent linear model to predict ammonium removal in ponds, which was proved to be, essentially, a function of ammonium surface loading rate. In general, all these models made reasonable predictions of ammonium or TN removal but tended to overestimate low ammonium effluent concentrations while underestimating higher values of field data. PMID:25521122

  10. Treatment of oilfield produced water by waste stabilization ponds.

    PubMed

    Shpiner, R; Vathi, S; Stuckey, D C

    2007-01-01

    Produced water (PW) from oil wells can serve as an alternative water resource for agriculture if the main pollutants (hydrocarbons and heavy metals) can be removed to below irrigation standards. Waste stabilization ponds seem like a promising solution for PW treatment, especially in the Middle East where solar radiation is high and land is available. In this work, hydrocarbon removal from PW in a biological waste stabilization pond was examined at lab-scale followed by an intermittent slow sand filter. The system was run for 300 days and removed around 90% of the oil in the pond, and 95% after the sand filter. COD removal was about 80% in the pond effluent, and 85% after the filter. The system was tested under various operational modes and found to be stable to shock loads. Installation of oil booms and decantation of surface oil seem to be important in order to maintain good system performance over time. PMID:17591220

  11. Pathogens and fecal indicators in waste stabilization pond systems with direct reuse for irrigation: Fate and transport in water, soil and crops.

    PubMed

    Verbyla, M E; Iriarte, M M; Mercado Guzmán, A; Coronado, O; Almanza, M; Mihelcic, J R

    2016-05-01

    Wastewater use for irrigation is expanding globally, and information about the fate and transport of pathogens in wastewater systems is needed to complete microbial risk assessments and develop policies to protect public health. The lack of maintenance for wastewater treatment facilities in low-income areas and developing countries results in sludge accumulation and compromised performance over time, creating uncertainty about the contamination of soil and crops. The fate and transport of pathogens and fecal indicators was evaluated in waste stabilization ponds with direct reuse for irrigation, using two systems in Bolivia as case studies. Results were compared with models from the literature that have been recommended for design. The removal of Escherichia coli in both systems was adequately predicted by a previously-published dispersed flow model, despite more than 10years of sludge accumulation. However, a design equation for helminth egg removal overestimated the observed removal, suggesting that this equation may not be appropriate for systems with accumulated sludge. To assess the contamination of soil and crops, ratios were calculated of the pathogen and fecal indicator concentrations in soil or on crops to their respective concentrations in irrigation water (termed soil-water and crop-water ratios). Ratios were similar within each group of microorganisms but differed between microorganism groups, and were generally below 0.1mLg(-1) for coliphage, between 1 and 100mLg(-1) for Giardia and Cryptosporidium, and between 100 and 1000mLg(-1) for helminth eggs. This information can be used for microbial risk assessments to develop safe water reuse policies in support of the United Nations' 2030 Sustainable Development Agenda. PMID:26881733

  12. Renewable energy for the aeration of wastewater ponds.

    PubMed

    Hobus, I; Hegemann, W

    2003-01-01

    The application of a decentralised renewable energy supply for the aeration of wastewater ponds, and the influence of an unsteady oxygen supply on the specific conversion rate and biocoenose was investigated. With the discontinuous aeration the specific conversion rate is increased as compared to facultative ponds. The estimation of the microorganisms consortia was done with in situ hybridisation techniques. A significant shift in the bacteria population with the chosen specific probes for anaerobic, sulphate reducing and nitrifying bacteria could not be detected. Wastewater ponds have sufficient buffer volume to compensate for the fluctuating energy supply. But the efficiency of the energy supply of a photovoltaic plant decreases in shallow lakes (d < 1.5 m) corresponding to a high oxygen production of algae. For the layout of the individual components: photovoltaic and wind power plant, energy management, aeration system and wastewater pond, a simulation model was developed and tested. The application of renewable energy for the aeration of wastewater ponds is a useful alternative for the redevelopment of overloaded ponds as well as the construction of new wastewater ponds, especially in areas with an inadequate central electricity grid and a high availability of wind and solar energy. PMID:14510232

  13. Surface and subsurface soils at the Pond B dam: July 1998

    SciTech Connect

    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.

  14. Agricultural runoff pollution control by a grassed swales coupled with wetland detention ponds system: a case study in Taihu Basin, China.

    PubMed

    Zhao, Jinhui; Zhao, Yaqian; Zhao, Xiaoli; Jiang, Cheng

    2016-05-01

    The performance of a field grassed swales (GSs) coupled with wetland detention ponds (WDPs) system was monitored under four typical rainfall events to assess its effectiveness on agricultural runoff pollution control in Taihu Basin, China. The results indicated that suspended solids (SS) derived from the flush process has significant influence on pollution loads in agricultural runoff. Determination of first flush effect (FFE) indicated that total suspended solids (TSS) and total phosphorus (TP) exhibited moderate FFE, while chemical oxygen demand (COD) and total nitrogen (TN) showed weak FFE. Average removal efficiencies of 83.5 ± 4.5, 65.3 ± 6.8, 91.6 ± 3.8, and 81.3 ± 5.8 % for TSS, COD, TN, and TP were achieved, respectively. The GSs played an important role in removing TSS and TP and acted as a pre-treatment process to prevent clogging of the subsequent WDPs. Particle size distributions (PSDs) analysis indicated that coarse particles larger than 75 μm accounted for 80 % by weight of the total particles in the runoff. GSs can effectively reduce coarse particles (≥75 μm) in runoff, while its removal efficiency for fine particles (<75 μm) was low, even minus results being recorded, especially for particles smaller than 25 μm. The length of GSs is a key factor in its performance. The WDPs can remove particles of all sizes by sedimentation. In addition, WDPs can improve water quality due to their buffering and dilution capacity during rainfall as well as their water purification ability during dry periods. Overall, the ecological system of GSs coupled with WDPs is an effective system for agricultural runoff pollution control. PMID:26832867

  15. Enhancing Ecoefficiency in Shrimp Farming through Interconnected Ponds.

    PubMed

    Barraza-Guardado, Ramón Héctor; Arreola-Lizárraga, José Alfredo; Miranda-Baeza, Anselmo; Juárez-García, Manuel; Juvera-Hoyos, Antonio; Casillas-Hernández, Ramón

    2015-01-01

    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 m(3) 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. PMID:26525070

  16. Enhancing Ecoefficiency in Shrimp Farming through Interconnected Ponds

    PubMed Central

    Barraza-Guardado, Ramón Héctor; Arreola-Lizárraga, José Alfredo; Miranda-Baeza, Anselmo; Juárez-García, Manuel; Juvera-Hoyos, Antonio; Casillas-Hernández, Ramón

    2015-01-01

    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. PMID:26525070

  17. Groundwater impact assessment report for the 100-D Ponds

    SciTech Connect

    Alexander, D.J.

    1993-07-01

    The 183-D Water Treatment Facility (WTF) discharges effluent to the 120-0-1 Ponds (100-D Ponds) located north of the 100-D Area perimeter fence. This report satisfies one of the requirements of the Hanford Federal Facility Agreement and Consent Order (Tri-Party Agreement) Milestone M-17-00B as agreed by the US Department of Energy, Washington State Department of Ecology, and the US Environmental Protection Agency. Tri-Party Agreement Milestone M-17-00B includes a requirement to assess impacts to groundwater from disposal of the 183-D WTF effluent to the 100-D Ponds. In addition, the 100-D Ponds are a Resource Conservation and Recovery Act of 1976 treatment, storage, and disposal facility covered by the 100-D Ponds Closure Plan (DOE-RL 1993a). There is evidence of groundwater contamination, primarily nitrate, tritium, and chromium, in the unconfined aquifer beneath the 100-D Area and 100 Areas in general. The contaminant plumes are area wide and are a result of past-practice reactor and disposal operations in the 100-D Area currently being investigated as part of the 100-DR-1 and 100-HR-3 Operable Units (DOE-RL 1992b, 1992a). Based on current effluent conditions, continued operation of the 100-D Ponds will not adversely affect the groundwater quality in the 100-D Area. Monitoring wells near the pond have slightly higher alkaline pH values than wells in the rest of the area. Concentrations of known contaminants in these wells are lower than ambient 100-D Area groundwater conditions and exhibit a localized dilution effect associated with discharges to the pond. Hydraulic impact to the local groundwater system from these discharges is minor. The groundwater monitoring well network for the 100-D Ponds is adequate.

  18. Comparison of water quality and channel catfish production in earthen ponds or a biofloc technology production system

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Biofloc technology (BFT) production systems are being used more commonly to produce high yields of fish or shrimp because very high feed rates are possible. In an outdoor BFT production system, a complex of living organisms is closely associated with particulate organic matter and is maintained in s...

  19. Greenhouse Gas Exchange in Small Arctic Thaw Ponds

    NASA Astrophysics Data System (ADS)

    Laurion, I.; Bégin, P. N.; Bouchard, F.; Preskienis, V.

    2014-12-01

    Arctic lakes and ponds can represent up to one quarter of the land surface in permafrost landscapes, particularly in lowland tundra landscapes characterized by ice wedge organic polygons. Thaw ponds can be defined as the aquatic ecosystems associated to thawing of organic soils, either resulting from active layer processes and located above low-center peat polygons (hereafter low-center polygonal or LCP ponds), or resulting from thermokarst slumping above melting ice wedges linked to the accelerated degradation of permafrost (hereafter ice-wedge trough or IWT ponds). These ponds can merge together forming larger water bodies, but with relatively stable shores (hereafter merged polygonal or MPG ponds), and with limnological characteristics similar to LCP ponds. These aquatic systems are very small and shallow, and present a different physical structure than the larger thermokarst lakes, generated after years of development and land subsidence. In a glacier valley on Bylot Island, Nunavut, Canada, thermokarst and kettle lakes together represent 29% of the aquatic area, with a thermal profile resembling those of more standard arctic lakes (mixed epilimnion). The IWT ponds (44% of the area) are stratified for a large fraction of the summer despite their shallowness, while LCP and MPG ponds (27% of the area) show a more homogeneous water column. This will affect gas exchange in these diverse aquatic systems, in addition to their unique microbiota and organic carbon lability that control the production and consumption rates of greenhouse gases. The stratification in IWT ponds generates hypoxic conditions at the bottom, and together with the larger availability of organic carbon, stimulates methanogenesis and limits the mitigating action of methanotrophs. Overall, thaw ponds are largely supersaturated in methane, with IWT ponds dominating the emissions in this landscape (92% of total aquatic emissions estimated for the same valley), and they present large variations in

  20. A hybrid froth flotation-filtration system as a pretreatment for oil sands tailings pond recycle water management: Bench- and pilot-scale studies.

    PubMed

    Loganathan, Kavithaa; Bromley, David; Chelme-Ayala, Pamela; Gamal El-Din, Mohamed

    2015-09-15

    Through sustainable water management, oil sands companies are working to reduce their reliance on fresh water by minimizing the amount of water required for their operations and by recycling water from tailings ponds. This study was the first pilot-scale testing of a hybrid technology consisting of froth flotation combined with filtration through precoated submerged stainless steel membranes used to treat recycle water from an oil sands facility. The results indicated that the most important factor affecting the performance of the hybrid system was the influent water quality. Any rise in the levels of suspended solids or total organic carbon of the feed water resulted in changes of chemical consumption rates, flux rates, and operating cycle durations. The selections of chemical type and dosing rates were critical in achieving optimal performance. In particular, the froth application rate heavily affected the overall recovery of the hybrid system as well as the performance of the flotation process. Optimum surfactant usage to generate froth (per liter of treated water) was 0.25 mL/L at approximately 2000 NTU of influent turbidity and 0.015 mL/L at approximately 200 NTU of influent turbidity. At the tested conditions, the optimal coagulant dose was 80 mg/L (as Al) at approximately 2000 NTU of influent turbidity and <40 mg/L (as Al) at approximately 200 NTU of influent turbidity. Precoat loading per unit membrane surface area tested during the pilot study was approximately 30 g/m(2). The results of this study indicated that this hybrid technology can potentially be considered as a pre-treatment step for reverse osmosis treatment of recycle water. PMID:26164269

  1. Ultimate Heat Sink Cooling Pond and Spray Pond Analysis Models.

    1999-05-02

    Version 00 Three programs model performance of an ultimate heat sink cooling pond. National Weather Service data is read and analyzed to predict periods of lowest cooling performance and highest evaporative loss. The data is compared to local site data for significant differences. Then the maximum pond temperature is predicted. Five programs model performance of an ultimate heat sink spray pond. The cooling performance, evaporative water loss, and drift water loss as a function ofmore » windspeed are estimated for a spray field. These estimates are used in conjunction with National Weather Service data to predict periods of lowest cooling performance and highest evaporative loss. This data is compared to local site data for significant differences. Then the maximum pond temperature is predicted.« less

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

    USGS Publications Warehouse

    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

  3. Salt-gradient solar ponds: design, construction and power production

    SciTech Connect

    Wittenberg, L.J.

    1980-01-01

    Salt-gradient solar ponds are combined solar energy collectors and thermal storage systems. The ponds are made non-convective by the formation of a density-gradient composed of salt solutions whose concentrations increase with depth. The depth of the various layers of the pond determine the efficiency and thermal storage capacity of the system. The construction of the largest such pond in the US, 2000 m/sup 2/, was completed in 1978 for approximately $35/m/sup 2/. The pond is estimated to produce 1015 GJ/y of low-temperature heat at a cost of $8.95/GJ, when the installation costs are amortized over 15 y. Construction changes are suggested to improve the reliability of the system. Electrical power generation by the use of Rankine cycle turbogenerators connected to solar ponds has been demonstrated in Israel. Feasibility studies are in progress to propose electricity production of up to 2000 MW for projects near the Dead Sea in Israel, and 600 MW in a proposed project at the California Salton Sea.

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

    ERIC Educational Resources Information Center

    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…

  5. USING GIS TO MAP THE DEPTH TO SEDIMENT OF A POND USING A SONIC DEPTH METER AND A TRIMBLE GPS SYSTEM

    EPA Science Inventory

    During a research project to identify the source of Arsenic in a watershed, it became necessary to characterize the subsurface sediments in a pond associated with the watershed. This paper describes the process that we used to measure the depth and identify the location of the d...

  6. Stochastic dynamics of melt ponds and sea ice-albedo climate feedback

    NASA Astrophysics Data System (ADS)

    Sudakov, Ivan

    Evolution of melt ponds on the Arctic sea surface is a complicated stochastic process. We suggest a low-order model with ice-albedo feedback which describes stochastic dynamics of melt ponds geometrical characteristics. The model is a stochastic dynamical system model of energy balance in the climate system. We describe the equilibria in this model. We conclude the transition in fractal dimension of melt ponds affects the shape of the sea ice albedo curve.

  7. Sound management of sediment yields at the catchment scale by small detention ponds

    NASA Astrophysics Data System (ADS)

    Sikorska, A. E.; Wasilewicz, M.; Banasik, K.

    2012-04-01

    Keywords: small detention pond, sediment deposits, reservoir silting, urban catchment Globally observed land use and climate changes have a clear impact on the sediment yields deriving from the catchment. Released sediments may originate from different point and non-point sources. Thereby it is difficult to manage and reduce sediment loads directly at the source without undertaking detailed and expensive monitoring programs. Small detention ponds are therefore frequently used water management systems in urban settlements to improve water quality at the catchment scale. Such ponds located at the outlet of small basins allow reducing sediment loads downstream. Additionally, they capture sediment-associated contaminants as heavy metals, nutrients and micropollutants. On the other hand, a sedimentation within the pond may be a severe problem because it decreases over the time its retention capacity. This is especially significant for small detention ponds, where the siltation rate is high. These ponds can loose their total capacity already after few years of their exploitation when no dredging operations are considered. Unfortunately, maintenance costs of small ponds are expensive and usually not taken into account when planning and constructing such ponds. Consequently, many small detention ponds become inefficient after an entire use of their capacity. Therefore careful planning of maintenance options is essential to keep an effectiveness of such ponds on the expected level. Within presented here study we addressed the problem of silting small detention ponds and we assessed an applicability of such ponds to manage sediment yields discharged from small urban catchments. To this end, a periodic measurement of deposited sediments within a small detention pond (1.35 ha, 5 years old, Warsaw, Poland) has been undertaken. This pond receives a polluted runoff from a small urbanized basin (30 km2), for which no routine sediment measurement exists. The spatial sediment

  8. Pond Ecology in the Classroom.

    ERIC Educational Resources Information Center

    Kneidl, Sally Stenhouse

    1993-01-01

    Describes activities with organisms from freshwater ponds and ditches. Several experiments involve predation, some involve habitat choices, and one addressees the role of sunlight in supporting plant-eating animals. (PR)

  9. Par Pond vegetation status 1996

    SciTech Connect

    Mackey, H.E. Jr.; Riley, R.S.

    1996-12-01

    The water level of Par Pond was lowered approximately 20 feet in mid-1991 in order to protect downstream residents from possible dam failure suggested by subsidence on the downstream slope of the dam and to repair the dam. This lowering exposed both emergent and nonemergent macrophyte beds to drying conditions resulting in extensive losses. A survey of the newly emergent, shoreline aquatic plant communities of Par Pond began in June 1995, three months after the refilling of Par Pond to approximately 200 feet above mean sea level. These surveys continued in July, September, and late October, 1995, and into the early spring and late summer of 1996. Communities similar to the pre-drawdown, Par Pond aquatic plant communities continue to become re-established. Emergent beds of maidencane, lotus, waterlily, watershield, and Pontederia are extensive and well developed. Measures of percent cover, width of beds, and estimates of area of coverage with satellite data indicate regrowth within two years of from 40 to 60% of levels prior to the draw down. Cattail occurrence continued to increase during the summer of 1996, especially in the former warm arm of Par Pond, but large beds common to Par Pond prior to the draw down still have not formed. Lotus has invaded and occupies many of the areas formerly dominated by cattail beds. To track the continued development of macrophytes in Par Pond, future surveys through the summer and early fall of 1997, along with the evaluation of satellite data to map the extent of the macrophyte beds of Par Pond, are planned.

  10. Water treatment plant sludge disposal into stabilization ponds.

    PubMed

    Filho, Sidney Seckler Ferreira; Piveli, Roque Passos; Cutolo, Silvana Audrá; de Oliveira, Alexandre Alves

    2013-01-01

    Researchers have paid particular attention to the disposal of sludge produced in water treatment plants (WTPs) into wastewater treatment plants (WWTPs) for further processing, mainly because it is considered an attractive alternative for the treatment of waste generated in water production processes. This study evaluated the effects of flow equalization and disposal of sludge, from a conventional WTP, into a WWTP system that includes an anaerobic stabilization pond followed by a facultative pond. During the period of sludge discharge from the WTP into the wastewater system, the influent to the WWTP presented an increase of 17% (from 171 to 200 mg L(-1)) of total suspended solids (TSS) and a 7.0% flow rate increase, without showing adverse effects on the organic load, TSS and nutrients removal. The most significant impact observed in the WWTP was the increase of solids accumulation rate in the anaerobic pond, with a value of 141 mm/year during the sludge discharge period. The operating time, before the dredging and desludging cycles required for this specific anaerobic pond, decreased from 12.7 to 10.4 years, which is consistent with previous studies in literature. Thus, based on the observed parameters of this study, it is viable to release solids from a WTP effluent into a WWTP that includes anaerobic stabilization ponds followed by a facultative pond. Indeed, this process scheme becomes a viable technical, environmental, and economical alternative for small to medium WWTPs. PMID:23416593

  11. Experimental study of the salt gradient solar pond stability

    SciTech Connect

    Karim, Choubani; Slim, Zitouni; Kais, Charfi; Jomaa, Safi Mohamed; Akbarzadeh, Aliakbar

    2010-01-15

    Many natural systems such as oceans, lakes, etc.., are influenced by the effect of double-diffusive convection. This phenomenon, which is a combination of heat and mass transfer, can destroy the stability of system-flows. In the case of solar ponds the middle layer, that is linearly stratified, acts as a thermal and mass insulator for the lower layer. This middle layer, called the Non-Convective Zone (NCZ), needs special care to avoid convection and to maintain its stability. In fact, due to an excess of heat stored, a thermal gradient occurs within the NCZ. A convective movement appears at the bottom of the stratified-layers and then grows to a double-diffusive convection movement. This movement transforms the stratified-layers into a well mixed layer, reducing the storage capacity of the pond. Laboratory small-scale pond and middle-scale outdoor solar ponds were designed and built to provide both quantitative data and to study the dynamic processes in solar ponds, including the behavior of the gradient zone. Particle Image Velocimetry (PIV) visualization-experiments carried out in the mechanical and energetic laboratory in the engineering school of Tunisia and experiments in the field showed that the instability of solar ponds could be limited by using porous media placed in the lower layer of the stratification. (author)

  12. 2101-M pond closure plan. Volume 1, Revision 2

    SciTech Connect

    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.

  13. Systems and economic analysis of microalgae ponds for conversion of CO{sub 2} to biomass. Final report

    SciTech Connect

    Benemann, J.R.; Oswald, W.J.

    1996-03-21

    There is growing evidence that global warming could become a major global environmental threat during the 21st century. The precautionary principle commands preventive action, at both national and international levels, to minimize this potential threat. Many near-term, relatively inexpensive, mitigation options are available. In addition, long-term research is required to evaluate and develop advanced, possibly more expensive, countermeasures, in the eventuality that they may be required. The utilization of power plant CO{sub 2} and its recycling into fossil fuel substitutes by microalgae cultures could be one such long-term technology. Microalgae production is an expanding industry in the U.S., with three commercial systems (of approximately 10 hectare each) producing nutriceuticals, specifically beta-carotene, extracted from Dunaliella, and Spirulina biomass. Microalgae are also used in wastewater treatment. Currently production costs are high, about $10,000/ton of algal biomass, almost two orders of magnitude higher than acceptable for greenhouse gas mitigation. This report reviews the current state-of-the-art, including algal cultivation and harvesting-processing, and outlines a technique for achieving very high productivities. Costs of CO{sub 2} mitigation with microalgae production of oils ({open_quotes}biodiesel{close_quotes}) are estimated and future R&D needs outlined.

  14. Performance comparison between two equal stabilization ponds operating with and without sludge layer.

    PubMed

    Rodrigues, V A J; Possmoser-Nascimento, T E; Dias, D F C; Passos, R G; von Sperling, M; Vasel, J L

    2015-01-01

    Stabilization ponds are a highly appropriate system for treating sewage in small to medium size communities. However, sludge accumulation at the pond bottom occurs with the passage of time, reducing the net pond volume, which, in principle, could affect its performance. The objective of this paper is to compare the behaviour of two equal ponds in parallel treating the same flow of municipal wastewater from an upflow anaerobic sludge blanket reactor in Brazil. Each pond treated a population equivalent of around 125 inhabitants. One pond had approximately 40% of its net volume occupied by sludge after 11 years of operation, while the other pond had previously undergone complete desludging. The study covers the removal of biochemical oxygen demand (BOD), chemical oxygen demand (COD), suspended solids (SS), nitrogen fractions and coliforms. Owing to the presence of a sludge layer, the theoretical hydraulic retention time (HRT) was lower in the pond without sludge. For BOD, COD, SS and Escherichia coli there were no significant differences (Wilcoxon matched-pairs test) between both ponds. The pond without sludge had significantly better removal efficiencies in terms of total Kjeldahl nitrogen and ammonia-N. The sludge layer probably allowed the occurrence of removal mechanisms that compensated for the reduction caused in the HRT. PMID:25812104

  15. Holocene closure of Lib Pond, Marshall Islands.

    PubMed

    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. PMID:24638020

  16. Holocene Closure of Lib Pond, Marshall Islands

    PubMed Central

    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. PMID:24638020

  17. Blogging from North Pond

    NASA Astrophysics Data System (ADS)

    Marziali, C. G.; Edwards, K. J.

    2009-12-01

    Sea going research expeditions provide an ideal opportunity for outreach through blogs: the finite duration limits the author's commitment; scientists are usually in a remote location with fewer distractions; and fieldwork is visual and interesting to describe. Over four weeks this winter, Katrina Edwards of USC authored a blog about her deep-sea drilling expedition to North Pond, a depression in the ocean crust in the mid-Atlantic. She emailed daily dispatches and photos to USC Media Relations, which maintained a (still accessible) blog. Written for the general public, the blog quickly attracted interest from lay readers as well as from media organizations. Scientific American carried the blog on its web site, and the National Science Foundation linked to it in its "Science 360" electronic news digest. The blog also led to a Q&A with Edwards in the widely-read "Behind the Scenes" feature of LiveScience. Interest from science bloggers and National Geographic towards the end suggests that the blog could have expanded its reach given more time: expeditions lasting between six weeks and three months, such as occur during ocean drilling expeditions, would appear to be ideal candidates for a blog. Most importantly, the blog educated readers about the importance to planetary life of what Edwards calls the "intraterrestrials": the countless microbes that inhabit the oceanic crust and influence major chemical and biological cycles. Considering that the subjects of the expedition were invisible critters in a pitch-dark place, the blog shows what can be accomplished by scientists and institutions committed to public outreach.

  18. Solar Pond Fluid Dynamics and Heat Transfer

    NASA Technical Reports Server (NTRS)

    Jones, G. F.

    1984-01-01

    The primary objective of the solar pond research was to obtain an indepth understanding of solar pond fluid dynamics and heat transfer. The key product was the development of a validated one-dimensional computer model with the capability to accurately predict time-dependent solar pond temperature, salinities, and interface motions. Laboratory scale flow visualization experiments were conducted to better understand layer motion. Two laboratory small-scale ponds and a large-scale outdoor solar pond were designed and built to provide quantitative data. This data provided a basis for validating the model and enhancing the understanding of pond dynamic behavior.

  19. The Western Pond Turtle; Habitat and History, 1993-1994 Final Report.

    SciTech Connect

    Holland, Dan C.

    1994-08-01

    The western pond turtle is known from many areas of Oregon. The majority of sightings and other records occur in the major drainages of the Klamath, Rogue, Umpqua, Willamette and Columbia River systems. A brief overview is presented of the evolution of the Willamette-Puget Sound hydrographic basin. A synopsis is also presented of the natural history of the western pond turtle, as well as, the status of this turtle in the Willamette drainage basin. The reproductive ecology and molecular genetics of the western pond turtle are discussed. Aquatic movements and overwintering of the western pond turtle are evaluated. The effect of introduced turtle species on the status of the western pond turtle was investigated in a central California Pond. Experiments were performed to determine if this turtle could be translocated as a mitigation strategy.

  20. Locations and areas of ponds and Carolina Bays at the Savannah River Plant

    SciTech Connect

    Shields, J.D.; Woody, N.D.; Dicks, A.S.; Hollod, G.J.; Schalles, J.; Leversee, G.J.

    1982-05-01

    The Savannah River Plant has 28 ponds and 190 Carolina Bays on its 192,000-acreite. Excluding the Par Pond system, the mean pond area is 17.6 acre, with a range of 0.4 to 202.8 acres. Par Pond is the largest pond, with an area of 2500 acres. The mean Carolina Bay area is 6.6 acres, with a range of less than 0.3 to 124.0 acres. The geographical location of each pond and bay has been digitized and can be graphically displayed by computer. This capability will facilitate identification of wetland areas as required by Executive Order 11990 (Protection of Wetlands, May 24, 1977).

  1. Sediment particle size and initial radiocesium accumulation in ponds following the Fukushima DNPP accident

    PubMed Central

    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 (137Cs) in four irrigation ponds, ~4–5 months after the Fukushima Dai–ichi nuclear power plant (DNPP) accident. Trap efficiency, represented by the inventory of 137Cs in pond sediment to the inventory of radiocesium in soil surrounding the pond (i.e., total 137Cs 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 137Cs. In ponds showing low trap efficiency, fine sediment containing high concentrations of 137Cs 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 137Cs in pond sediment, as well as the amount lost through hydraulic flushing. PMID:24682011

  2. Increasing the collected energy and reducing the water requirements in salt-gradient solar ponds

    NASA Astrophysics Data System (ADS)

    Suarez, F. I.; Ruskowitz, J. A.; Tyler, S. W.; Childress, A. E.

    2013-12-01

    Salt-gradient solar ponds are low-cost, large-scale solar collectors with integrated storage that can be used as an energy source in many thermal systems. For instance, solar ponds have proven to be a promising solution to drive thermal desalination in arid zones. However, in zones with limited water availability, where evaporation constrains the use of solar ponds in areas with the greatest potential for solar energy development, evaporation losses at the surface of the pond constrain their use. Therefore, evaporation represents a significant challenge for development of these low-cost solar systems in arid settings. In this investigation, different transparent floating elements were tested to suppress evaporation: flat discs, hemispheres, and a continuous cover. Flat discs were the most effective evaporation suppression element. Evaporation decreased from 4.8 to 2.5 mm/day when 88% of the pond was covered with the flat discs. In addition, the highest temperature increased from 34 to 43°C and the heat content increased from 179 to 220 MJ (a 22% increase). Reduced evaporative losses at the surface of the pond resulted in lower conductive losses from the storage zone and increased the collected energy. The magnitude of evaporation reduction observed in this work is important as it allows solar pond operation in locations with limited water supply for replenishment. The increase in stored heat allows more energy to be withdrawn from the pond for use in external applications, which significantly improves the thermal efficiencies of solar ponds.

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

    NASA Astrophysics Data System (ADS)

    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

  4. ENVIRONMENTAL EFFECTS OF WESTERN COAL SURFACE MINING. PART IV--CHEMICAL AND MICROBIOLOGICAL INVESTIGATIONS OF A SURFACE COAL MINE SETTLING POND

    EPA Science Inventory

    Chemical and microbiological investigations of the settling pond system at the West Decker Coal Mine in southeastern Montana were undertaken during 1975-1977. Concentrations of total dissolved solids, bicarbonate, sodium, sulfate, and nitrogen species in pond water were elevated ...

  5. Relative performance of duckweed ponds and rock filtration as advanced in-pond wastewater treatment processes for upgrading waste stabilisation pond effluent: a pilot study.

    PubMed

    Short, M D; Cromar, N J; Nixon, J B; Fallowfield, H J

    2007-01-01

    An experimental pilot plant was operated over a five month period to assess the relative treatment performances of: a duckweed (DW) pond; a rock filter (RF); and an open pond (OP); for the upgrading of final WSP effluent prior to reuse applications. Each pilot treatment system consisted of three identical ponds arranged in three parallel series, each fed a continuous flow of wastewater from the local Bolivar treatment plant. Light penetration profiling for the DW and OP systems revealed some 55% greater light attenuation capacity for DW ponds compared to the OP system. Results showed a significantly elevated performance capacity for the RF treatment with respect to BOD5, SS, turbidity and NH4-N removal, but equal treatment performances for algal (chlorophyll) removal. No significant performance differences were evident between the DW and OP treatments for any of the monitored parameters. Soluble reactive phosphorus, faecal coliform and E. coli removals were similar for all pilot treatment systems. Rock filters not only demonstrated an enhanced performance capacity in terms of removal of loaded parameters, but also showed greater reliability of performance and produced a consistently higher quality final effluent. Rock filters demonstrated greater potential over both DW and OP systems for the upgrading of WSP effluent prior to reuse application. PMID:17591203

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

    PubMed

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

    PubMed Central

    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 m3/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

  8. Par Pond Fish, Water, and Sediment Chemistry

    SciTech Connect

    Paller, M.H.; 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.

  9. Stabilization Pond Operation and Maintenance Manual.

    ERIC Educational Resources Information Center

    Sexauer, Willard N.; Karn, Roger V.

    This manual provides the waste stabilization pond operator with the basics necessary for the treatment of wastewater in stabilization ponds. The material is organized as a comprehensive guide that follows the normal operation and maintenance procedures from the time the wastewater enters the left station until it leaves the pond. A comprehensive…

  10. Distance Education of Pennsylvania Pond Owners.

    ERIC Educational Resources Information Center

    Schmidt, Katherine L.; Swistock, Bryan R.; Sharpe, William E.

    2003-01-01

    Evaluations by 175 of 557 Pennsylvania pond owners who attended an Extension program via satellite revealed that most were interested in aesthetic/recreational pond use and pond management. They wanted more in-depth information over a shorter time frame. Only 10% did not favor satellite delivery. Shorter, more focused satellite programs and…

  11. Modelling faecal coliform mortality in water hyacinths ponds

    NASA Astrophysics Data System (ADS)

    Mayo, A. W.; Kalibbala, M.

    Removal of faecal coliforms was investigated in pilot-scale water hyacinths ponds. The investigation was conducted to evaluate the role of solar intensity, pH, dissolved oxygen, temperature, sedimentation, and attachment of faecal coliforms on Eichhornia crassipes on disappearance of bacteria in water hyacinths ponds. A mathematical model that used the plug flow philosophy and incorporating the aforementioned factors was developed to predict faecal coliform mortality rate. The proposed multifactor model satisfactorily predicted mortality rate of faecal coliforms in a pilot-scale water hyacinths ponds. After optimization of the parameters, mortality rate constant for pH ( kpH) was 0.001, mortality rate constant for DO ( kDO) was 0.0037 and solar intensity mortality rate constant k s was 0.0102 cm 2/cal. The results also showed that the thickness of biofilm ( Lf) was 2.5 × 10 -4 m, and the effective surface area of water hyacinths roots per unit surface area of pond ( Rs) was 10.4 m 2/m 2. The results further showed that environmental factors such as solar intensity and pH were the key factors when water hyacinths ponds have a large exposed surface area. However, attachment of bacteria to water hyacinths played a major role in ponds fully covered with water hyacinths. The inclusion of sedimentation parameters in the model improved model efficiency by only 3.2%. It was concluded that sedimentation is not a major factor governing faecal coliform disappearance in water hyacinths pond systems receiving pretreated wastewaters.

  12. Topics in gradient maintenance and slat recycling in an operational solar pond

    SciTech Connect

    Swift, A.H.P.; Golding, P. . Dept. of Mechanical and Industrial Engineering)

    1992-02-01

    Since 1986, the 3355 m{sup 2} salt gradient solar pond facility in El Paso, Texas, has operated with a temperature difference between the upper and lower zones of 55 to 75{degrees}C while delivering industrial process heat, grid-connected electrical power, and thermal energy for the experimental production of desalted water. Because the El Paso solar pond is an inland facility, it is necessary to recycle the salt in a sustainable salt management system. A method that uses the main pond surface for initial brine concentration and short-term storage was developed after it became evident that the original evaporation pond system was undersized. This paper examines the method for brine concentration and storage, the effects of a brine storage zone on pond operation, and the installation of an enhanced evaporation net system and an automatic scanning injection system. A short description of the performance history and current status of the project is also included.

  13. Feasibility of using saturated solar ponds for brine unmixing. Final report

    SciTech Connect

    Not Available

    1980-09-30

    The overall objective of this study was to investigate in the laboratory the feasibility of using saturated solar ponds for unmixing a brine of intermediate concentration into dilute and concentrated brine streams for salinity gradient energy conversion systems. This objective was accomplished by conducting experiments on laboratory saturated ponds using borax, potassium perchlorate, potassium nitrate, disodium phosphate and potassium alum. Results from ponds using borax, potassium nitrate and disodium phosphate conclusively demonstrated that saturated solar ponds can self-generate and self-maintain a stable density gradient. Moreover, these ponds reestablished stable density profiles after the ponds were externally mixed. Based on preliminary results, the residence time for unmixing of a brine of intermediate concentration into dilute and concentrated brine streams varies from a few days for the borax pond to about two weeks for the disodium phosphate pond, depending upon the characteristics of the individual saturated solution. Because of only a very small increase in the density of saturated solutions from 25/sup 0/C to 90/sup 0/C, the potassium perchlorate pond could not establish a stable density stratification.

  14. New factors in the design, operation and performance of waste-stabilization ponds

    PubMed Central

    Marais, G. v. R.

    1966-01-01

    In the developing countries, the unit costs of waste-stabilization ponds are generally low. Moreover, in the tropics and subtropics, the environmental conditions are conducive to a high level of pond performance. In view of this, the theory, operation and performance of such ponds under these conditions have been studied. It is shown that the Hermann & Gloyna and Marais & Shaw theories of the degradation action in oxidation ponds can be integrated, and that account can be taken of the effect of the sludge layer. In Lusaka, Zambia, anaerobic conditions are much more likely to occur in summer than in winter, because of intense stratification. It is confirmed that a series of maturation or oxidation ponds is more efficient than a single pond of equivalent volume. When aqua privies and septic tanks are used as anaerobic pretreatment units, the area of the primary oxidation ponds can be reduced and there is less likelihood that anaerobic conditions will develop in them in summer. The use of self-topping aqua privies, discharging through sewers to oxidation ponds, has made possible the economic installation of water-carriage systems of waste disposal in low-cost high-density housing areas. In the oxidation ponds, typhoid bacteria appear to be more resistant than indicator organisms; helminths, cysts and ova settle out; there are no snails and, if peripheral vegetation is removed, mosquitos will not breed. PMID:5296235

  15. Systems and economic analysis of microalgae ponds for conversion of CO{sub 2} to biomass. 4th Quarterly technical progress report

    SciTech Connect

    Benemann, J.R.

    1994-12-28

    Microalgae cultivation in large open ponds is the only photosynthetic process likely to directly utilize power plant flue gas CO{sub 2} for production of biomass. The algal biomass can be converted into substitutes for fossil fuels, in particular liquid fuels such as biodiesel (vegetable oil methyl or ethyl esters), thus reducing atmospheric CO{sub 2} levels and the potential for global warming. This concept is being investigated, among others, at the National Renewable Energy Laboratory at Golden, Colorado, with support from PETC.

  16. Electric Trees and Pond Creatures.

    ERIC Educational Resources Information Center

    Weaver, Helen; Hounshell, Paul B.

    1978-01-01

    Two learning activities are presented to develop observation and classification skills at the elementary level. The first is an electric box that associates tree names with leaf and bark specimens, and the second is a pond water observation and slide preparation activity. (BB)

  17. How Healthy Is Our Pond?

    ERIC Educational Resources Information Center

    Sterling, Donna R.; Hargrove, Dori L.

    2014-01-01

    With crosscutting concepts such as stability and change in the "Next Generation Science Standards," this article was written for those who have wondered how to teach these concepts in a way that is relevant to students. In this investigation, students ask the question, "Why is the pond dirty?" As students investigate the health…

  18. Regional applicability and potential of salt-gradient solar ponds in the United States. Volume 2: Detailed report

    NASA Technical Reports Server (NTRS)

    Lin, E. I. H.

    1982-01-01

    A comprehensive assessment of the regional applicability and potential of salt-gradient solar ponds in the United States is provided. The assessment is focused on the general characteristics of twelve defined geographic regions. Natural resources essential to solar ponds are surveyed. Meteorological and hydrogeological conditions affecting pond performance are examined. Potentially favorable pond sites are identified. Regional thermal and electrical energy output from solar ponds is calculated. Selected pond design cases are studied. Five major potential market sectors are evaluated in terms of technical and energy-consumption characteristics, and solar-pond applicability and potential. Relevant pond system data and financial factors are analyzed. Solar-pond energy costs are compared with conventional energy costs. The assessment concludes that, excepting Alaska, ponds are applicable in all regions for at least two market sectors. Total solar pond energy supply potential in the five market sectors examined is estimated to be 8.94 quads/yr by the year 2000, approximately 7.2% of the projected total national energy demand.

  19. Oxidation pond for municipal wastewater treatment

    NASA Astrophysics Data System (ADS)

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

    2015-04-01

    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.

  20. Comparison of simple, small, full-scale sewage treatment systems in Brazil: UASB-maturation ponds-coarse filter; UASB-horizontal subsurface-flow wetland; vertical-flow wetland (first stage of French system).

    PubMed

    von Sperling, M

    2015-01-01

    This paper presents a comparison between three simple sewage treatment lines involving natural processes: (a) upflow anaerobic sludge blanket (UASB) reactor-three maturation ponds in series-coarse rock filter; (b) UASB reactor-horizontal subsurface-flow constructed wetland; and (c) vertical-flow constructed wetlands treating raw sewage (first stage of the French system). The evaluation was based on several years of practical experience with three small full-scale plants receiving the same influent wastewater (population equivalents of 220, 60 and 100 inhabitants) in the city of Belo Horizonte, Brazil. The comparison included interpretation of concentrations and removal efficiencies based on monitoring data (organic matter, solids, nitrogen, phosphorus, coliforms and helminth eggs), together with an evaluation of practical aspects, such as land and volume requirements, sludge production and handling, plant management, clogging and others. Based on an integrated evaluation of all aspects involved, it is worth emphasizing that each system has its own specificities, and no generalization can be made on the best option. The overall conclusion is that the three lines are suitable for sewage treatment in small communities in warm-climate regions. PMID:25714630

  1. Relation between species assemblages of fishes and water quality in salt ponds and sloughs in South San Francisco Bay

    USGS Publications Warehouse

    Mejia, F.; Saiki, M.K.; Takekawa, J.Y.

    2008-01-01

    This study was conducted to characterize fishery resources inhabiting salt-evaporation ponds and sloughs in South San Francisco Bay, and to identify key environmental variables that influence distribution of fishes. The ponds, which were originally constructed and operated for commercial production of salt, have undergone preliminary modifications (installation of culverts, gates, and other water-control structures) in preparation for full restoration to mostly tidal wetlands over the next 2 decades. We sampled fish from two salt-pond complexes (Alviso complex and Eden Landing complex), each consisting of several pond systems and their associated sloughs. Cluster analysis of species of fish indicated that at least two species assemblages were present, one characteristic of ponds and the other characteristic of sloughs and slough-like ponds. The slough-like ponds exhibited water-quality conditions (especially salinity) that resembled conditions found in the sloughs. Pond fishes were represented by 12 species, whereas slough fishes were represented by 22 species. Except for bay pipefish (Syngnathus leptorhynchus), which was unique to ponds, all species present in ponds also were in sloughs and slough-like ponds. These results indicated that species of fish in ponds originated from the sloughs. According to canonical-discriminant analysis, four environmental variables were useful for discriminating between the two species assemblages. Most discriminatory power was contributed by the index of habitat connectivity, a measure of minimum distance that a fish must travel to reach a particular pond from the nearest slough. Apparently, as fish from sloughs enter and move through interconnected salt ponds, environmental stress factors increase in severity until only the more tolerant species remain. The most likely source of stress is salinity, because this variable was second in importance to the index of habitat connectivity in discriminating between the two species

  2. Solar pond power plant feasibility study for Davis, California

    NASA Technical Reports Server (NTRS)

    Wu, Y. C.; Singer, M. J.; Marsh, H. E.; Harris, J.; Walton, A. L.

    1982-01-01

    The feasibility of constructing a solar pond power plant at Davis, California was studied. Site visits, weather data compilation, soil and water analyses, conceptual system design and analyses, a material and equipment market survey, conceptual site layout, and a preliminary cost estimate were studied. It was concluded that a solar pond power plant is technically feasible, but economically unattractive. The relatively small scale of the proposed plant and the high cost of importing salt resulted in a disproportionately high capital investment with respect to the annual energy production capacity of the plant. Cycle optimization and increased plant size would increase the economical attractiveness of the proposed concept.

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

    PubMed

    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. PMID:23869702

  4. Toxicity of stormwater treatment pond sediments to Hyalella azteca (Amphipoda)

    SciTech Connect

    Karouna-Renier, N.K.; Sparling, D.W.

    1997-04-01

    Stormwater runoff from highways and commercial, industrial, and residential areas contains a wide spectrum of pollutants including heavy metals, petroleum hydrocarbons, pesticides, herbicides, sediment, and nutrients. Recent efforts to reduce the impacts of urbanization on natural wetlands and other receiving waters have included the construction of stormwater treatment ponds and wetlands. These systems provide flood control and improve water quality through settling, adsorption, and precipitation of pollutants removing up to 95% of metals, nutrients and sediment before discharged from the site. The design of stormwater ponds to provide habitat for aquatic wildlife has prompted concern over the potential exposure of aquatic organisms to these contaminants. Aquatic sediments concentrate a wide array of organic and inorganic pollutants. Although water quality criteria may not be exceeded, organisms living in or near the sediments may be adversely affected. The availability of chemicals in sediments depends strongly on the prevailing chemistry. Physical conditions of the sediment and water quality characteristics including pH, redox potential and hardness, also influence contaminant availability. Studies have shown that heavy metals and nutrients carried by runoff concentrate in the sediment of stormwater ponds. Although several investigations have assessed the toxicity of sediments in streams receiving urban runoff, there have been few studies of the toxicity of stormwater treatment pond sediments to aquatic organisms. This study was part of a large-scale assessment of the contaminant hazards of stormwater treatment ponds. The objective of this study was to evaluate the toxicity of sediments and water from stormwater ponds over a 10-d period to juvenile Hyalella azteca. Bioassay results were related to concentrations of acid volatile sulfides and metals of the tested sediments. 17 refs., 4 tabs.

  5. Snow Dunes: A Controlling Factor of Melt Pond Distribution on Arctic Sea Ice

    NASA Technical Reports Server (NTRS)

    Petrich, Chris; Eicken, Hajo; Polashenski, Christopher M.; Sturm, Matthew; Harbeck, Jeremy P.; Perovich, Donald K.; Finnegan, David C.

    2012-01-01

    The location of snow dunes over the course of the ice-growth season 2007/08 was mapped on level landfast first-year sea ice near Barrow, Alaska. Landfast ice formed in mid-December and exhibited essentially homogeneous snow depths of 4-6 cm in mid-January; by early February distinct snow dunes were observed. Despite additional snowfall and wind redistribution throughout the season, the location of the dunes was fixed by March, and these locations were highly correlated with the distribution of meltwater ponds at the beginning of June. Our observations, including ground-based light detection and ranging system (lidar) measurements, show that melt ponds initially form in the interstices between snow dunes, and that the outline of the melt ponds is controlled by snow depth contours. The resulting preferential surface ablation of ponded ice creates the surface topography that later determines the melt pond evolution.

  6. How to maximally support local and regional biodiversity in applied conservation? Insights from pond management.

    PubMed

    Lemmens, Pieter; Mergeay, Joachim; De Bie, Tom; Van Wichelen, Jeroen; De Meester, Luc; Declerck, Steven A J

    2013-01-01

    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. PMID:23951328

  7. How to Maximally Support Local and Regional Biodiversity in Applied Conservation? Insights from Pond Management

    PubMed Central

    Lemmens, Pieter; Mergeay, Joachim; De Bie, Tom; Van Wichelen, Jeroen; De Meester, Luc; Declerck, Steven A. J.

    2013-01-01

    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. PMID:23951328

  8. Perched Lava Pond Complex on South Rift of Axial Volcano Revealed in AUV Mapping

    NASA Astrophysics Data System (ADS)

    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

  9. Methylmercury cycling in High Arctic wetland ponds: sources and sinks.

    PubMed

    Lehnherr, Igor; St Louis, Vincent L; Emmerton, Craig A; Barker, Joel D; Kirk, Jane L

    2012-10-01

    The sources of methylmercury (MeHg; the toxic form of mercury that is biomagnified through foodwebs) to Arctic freshwater organisms have not been clearly identified. We used a mass balance approach to quantify MeHg production in two wetland ponds in the Lake Hazen region of northern Ellesmere Island, NU, in the Canadian High Arctic and to evaluate the importance of these systems as sources of MeHg to Arctic foodwebs. We show that internal production (1.8-40 ng MeHg m(-2) d(-1)) is a much larger source of MeHg than external inputs from direct atmospheric deposition (0.029-0.051 ng MeHg m(-2) d(-1)), as expected. Furthermore, MeHg cycling in these systems is dominated by Hg(II) methylation and MeHg photodemethylation (2.0-33 ng MeHg m(-2) d(-1)), which is a sink for a large proportion of the MeHg produced by Hg(II) methylation in these ponds. We also show that MeHg production in the two study ponds is comparable to what has previously been measured in numerous more southerly systems known to be important MeHg sources, such as temperate wetlands and lakes, demonstrating that wetland ponds in the High Arctic are important sources of MeHg to local aquatic foodwebs. PMID:22779785

  10. Saturated solar ponds: 3. Experimental verification

    SciTech Connect

    Subhakar, D.; Murthy, S.S. )

    1994-12-01

    An experimental saturated solar pond is constructed using magnesium chloride salt. The temperature and concentration gradients are developed by heating the pond from the bottom and adding finely powdered salt from the top. The development of a temperature profile in the pond exposed to direct sunlight and its daily variation are studied. The predictions of the temperature profiles, using the authors' mathematical model, match the experiments better than the concentration profiles.

  11. Cooling ponds/lakes and fish

    SciTech Connect

    Monzingo, R.G.; Hughes, J.H.

    1980-01-01

    The discussions concern both cooling ponds and cooling lakes. By regulatory definition, cooling ponds, also called perched ponds, are constructed by building dikes and pumping water, usually from a nearby river, into the diked area. Cooling lakes on the other hand, are created by damming a stream or streams, thereby producing impoundments. The paper begins the discussion with a more detailed examination of the problem at the Collins Station.

  12. Review of SERI Solar Pond Work

    NASA Technical Reports Server (NTRS)

    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.

  13. Greenhouse gas emissions from stabilization ponds in subtropical climate.

    PubMed

    Hernandez-Paniagua, I Y; Ramirez-Vargas, R; Ramos-Gomez, M S; Dendooven, L; Avelar-Gonzalez, F J; Thalasso, F

    2014-01-01

    Waste stabilization ponds (WSPs) are a cost-efficient method to treat municipal and non-toxic industrial effluents. Numerous studies have shown that WSPs are a source of greenhouse gas (GHG). However, most reports concerned anaerobic ponds (AP) and few have addressed GHG emissions from facultative (FP) and aerobic/maturation ponds (MPs). In this paper, GHG emissions from three WSP in series are presented. These WSPs were designed as anaerobic, facultative and aerobic/maturation and were treating agricultural wastewater. CH4 fluxes from 0.6 +/- 0.4 g CH4 m(-2) d(-1) in the MP, to 7.0 +/- 1.0 g CH4 m(-2) d(-1) in the (AP), were measured. A linear correlation was found between the loading rates of the ponds and CH4 emissions. Relatively low CO2 fluxes (0.2 +/- 0.1 to 1.0 +/- 0.8 g CO2 m(-2) d(-1)) were found, which suggest that carbonate/bicarbonate formation is caused by alkaline pH. A mass balance performed showed that 30% of the total chemical oxygen demand removed was converted to CH4. It has been concluded that the WSP system studied emits at least three times more GHG than aerobic activated sludge systems and that the surface loading rate is the most important design parameter for CH4 emissions. PMID:24645453

  14. Disappearing Arctic Tundra Ponds: Assessing 60 Years of Change in the Barrow Peninsula, Alaska

    NASA Astrophysics Data System (ADS)

    Andresen, C.; Lougheed, V.

    2012-12-01

    Decadal hydrological changes of closed-basin tundra ponds in continuous permafrost fills a missing gap in arctic fresh water research. Furthermore, the lack of historic datasets and high resolution historical imagery adds to the challenge of understanding the long-term trends of these ecosystems. Given the dominance of these aquatic ecosystems in the Arctic landscape, documenting hydrological changes is important to understand carbon and energy balance, trophic energy flow, and biodiversity. We utilized historic aerial imagery from USGS archives of 1948 and modern high-resolution Quickbird imagery from 2008 to assess areal changes in arctic ponds over the past 60 years. Object-oriented classification was used to extract the areal extent of ponds and validated using a combination of ground-based measurements such as Kite Aerial Photography (KAP) and Differential Geographic Positioning System (DGPS). A total of 1120 ponds in different drained thaw lake basins (DTLB) distributed across the Barrow Peninsula were assessed. Analysis indicated a decline in total pond area and a decrease of 36% in the number of ponds, with change more pronounced in smaller ponds (<100m2). Aquatic plant cover data collected over a 40 year period (1970-2012) indicate that expansion of vegetation into the ponds may be a primary mechanism whereby ponds may experience infilling. Other mechanisms may include increased evaporation due to warmer and longer summers, transpiration from encroaching aquatic grasses and changes in precipitation patterns. However, images from additional years will be analyzed to separate out the roles of these variables on inter- versus intra-annual variability in pond surface area.

  15. Pond Identification, Classification, and Inundation Dynamics at St. Marks National Wildlife Refuge in northwest Florida, USA

    NASA Astrophysics Data System (ADS)

    Riley, J. W.; Calhoun, D.; Barichivich, J.

    2012-12-01

    The persistence and resilience of amphibian communities is largely dependent on adequate breeding habitat. This is especially important for threatened and endangered species that may often exist as isolated populations and have specific requirements for breeding. A study currently being conducted by the U.S. Geological Survey is investigating the feasibility of a repatriation effort of the Striped Newt (Notophthalmus perstriatus), a federal candidate species, within the St. Marks National Wildlife Refuge (SMNWR) in northwest Florida. This amphibian species requires ponds that are free of fishes and, for this reason, generally chooses ephemeral ponds as breeding sites. The delineation of potential breeding habitat is a first step in selecting candidate areas for repatriation. To achieve this, a LIDAR (Light Detection and Ranging) derived digital elevation model (DEM) and a topographic position index (TPI) classification scheme was used to identify and classify isolated depressions across the landscape. The TPI evaluates the difference in elevation from a central DEM cell to the mean elevation of a neighborhood of surrounding DEM cells and is a robust tool for locating depressional features within a landscape. These candidate depression features were then screened to remove large perennial ponds and smaller connected ponds from further consideration. In addition, the perimeters of twenty-two field identified ephemeral ponds were surveyed with a high precision RTK GPS (Real Time Kinematic Global Positioning System) unit to provide a calibration dataset to evaluate the performance of the feature identification method. This set of ponds was also instrumented with water-level recorders to investigate inundation dynamics across a wide range of hydrologic conditions. We anticipate being able to classify pond hydroperiod—thus each pond's potential as breeding habitat—at the monitored locations through this combination of approaches. Using estimates of pond size

  16. Visibility from Roads Predict the Distribution of Invasive Fishes in Agricultural Ponds

    PubMed Central

    Kizuka, Toshikazu; Akasaka, Munemitsu; Kadoya, Taku; Takamura, Noriko

    2014-01-01

    Propagule pressure and habitat characteristics are important factors used to predict the distribution of invasive alien species. For species exhibiting strong propagule pressure because of human-mediated introduction of species, indicators of introduction potential must represent the behavioral characteristics of humans. This study examined 64 agricultural ponds to assess the visibility of ponds from surrounding roads and its value as a surrogate of propagule pressure to explain the presence and absence of two invasive fish species. A three-dimensional viewshed analysis using a geographic information system quantified the visual exposure of respective ponds to humans. Binary classification trees were developed as a function of their visibility from roads, as well as five environmental factors: river density, connectivity with upstream dam reservoirs, pond area, chlorophyll a concentration, and pond drainage. Traditional indicators of human-mediated introduction (road density and proportion of urban land-use area) were alternatively included for comparison instead of visual exposure. The presence of Bluegill (Lepomis macrochirus) was predicted by the ponds' higher visibility from roads and pond connection with upstream dam reservoirs. Results suggest that fish stocking into ponds and their dispersal from upstream sources facilitated species establishment. Largemouth bass (Micropterus salmoides) distribution was constrained by chlorophyll a concentration, suggesting their lower adaptability to various environments than that of Bluegill. Based on misclassifications from classification trees for Bluegill, pond visual exposure to roads showed greater predictive capability than traditional indicators of human-mediated introduction. Pond visibility is an effective predictor of invasive species distribution. Its wider use might improve management and mitigate further invasion. The visual exposure of recipient ecosystems to humans is important for many invasive species that

  17. Elimination and accumulation of polycyclic aromatic hydrocarbons in urban stormwater wet detention ponds.

    PubMed

    Istenic, Darja; Arias, Carlos A; Matamoros, Víctor; Vollertsen, Jess; Brix, Hans

    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 with sand filters and other means to improve the removal of micropollutants. The concentrations of sigmaPAH in the sediments varied between 6 +/- 5 and 2,222 +/- 603 ng g(-1) dry weight (mean +/- standard deviation), and were highest in the ponds with lower pond volume per catchment area and did not clearly reflect different activities in the catchments. In general, the concentrations of PAHS in the sediments decreased from inlet to outlet, especially in the systems with good conditions for sedimentation such as systems with flow perpendicular sand dikes and extensive submerged vegetation. High molecular weight PAHs were predominant in the sediments indicating the pyrogenic origin of the PAHS. There was no correlation between PAH species concentrations in water or sediments and their hydrophobicity (log K(ow)). PAH concentrations in water fluctuated in response to intensity and frequency of rain events, whereas 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. PMID:22097066

  18. Determining the Chemical and Biological Availability of Zinc in Urban Stormwater Retention Ponds

    NASA Astrophysics Data System (ADS)

    Camponelli, K.; Casey, R.; Lev, S. M.; Landa, E. R.; Snodgrass, J.

    2005-12-01

    Highway runoff has the potential to negatively impact receiving systems due to transport of contaminants that accumulate on road surfaces. Metals such as copper and zinc are major components of automobile brake pads and tires, respectively. As these automobile parts are degraded, these metal containing particulates are deposited on the roadway and are washed into storm water retention ponds and surface water bodies during precipitation events. It has been estimated that 15 to 60% of the Zn in urban stormwater runoff comes from tire wear and that tire wear is a significant source of Zn to the environment with release inventories comparable to waste incineration sources. In urban and sub-urban systems, this large source of Zn can accumulate in stormwater retention ponds which serve as habitat for a variety of species. Understanding the chemical and biological availability of Zn to biota is integral to assessing the habitat quality of retention ponds. This study is a first effort to relate the amount and speciation of Zn in a retention pond to Zn inputs through highway-derived runoff events. In addition, results suggest that the chemical speciation and availability of particulate Zn can be related to the bioavailability and toxicity of Zn to pond organisms (i.e. larval amphibians). The study site in Owings Mills, MD is located next to a four-lane highway from which it receives runoff through a single culvert. Five species of anurans are known to utilize the pond as a breeding site and Zn in amphibian tissues and retention pond sediments were highly elevated at this site in 2001 and 2002. A recent analysis of pond sediments, soils, roadway dust and storm water collected at this site suggests that roadway particulate matter transported during runoff events is the dominant source of Zn in this system. Overall, Zn and other trace metals were found to be most abundant in the clay sized faction of pond sediments and soils. The pond cores were found to have higher Zn and Cu

  19. Origin and flatness of ponds on asteroid 433 Eros

    NASA Astrophysics Data System (ADS)

    Roberts, J. H.; Prockter, L. M.; Barnouin, O. S.; Ernst, C. M.; Kahn, E.; Gaskell, R. W.

    2013-12-01

    Over 300 landforms have been identified on asteroid 433 Eros, consisting of flat, smooth deposits typically located at the bottoms of craters or other topographic lows [1-2]. These landforms are tens of meters across, and their surfaces appear to lie on a geopotential [2]. They are clearly delineated from the surrounding terrain by sharp embayments of the bounding depressions in which they lie. Where these depressions are emplaced on a local slope, the deposits are located downslope of the geometric center of the crater [1]. The deposits are slightly bluer in color than the surroundings [1] and are interpreted to consist of fine-grained material [2]. Because of their morphological resemblance to the terrestrial lacustrine features of similar size, these deposits have been called "ponds". A database of the locations and sizes of 334 ponds observed with the Multi-spectral Imager (MSI) on the Near-Earth Asteroid Rendezvous (NEAR)-Shoemaker spacecraft has been archived in the Planetary Data System (PDS) [3]. These ponds are largely concentrated near the equator at the ends of the long-axis of the asteroid [2]. Several mechanisms have been proposed for the origin of the ponds including electrostatic levitation of dust [2], seismic shaking due to impacts [1] and disaggregation of central boulders observed within several of the ponds [4]. Here, we further investigate the topography of ponds on Eros using a new shape model derived from stereophotoclinometric (SPC) analysis [5], which we have tied to altimetry measurements made by the NEAR Laser Rangefinder (NLR). We update the locations of 55 pond candidates identified in images registered to the new shape model. We classify the flatness of these features according to the behavior of the first and second derivatives of the topography. We find that a significant fraction (55% - 75%) of pond candidates do not have flat floors. On the basis of these results, we favor an origin for the ponds deposits from a source external to

  20. A Landsat analysis of variability of supraglacial ponds for the debris-covered glaciers of the Langtang Valley

    NASA Astrophysics Data System (ADS)

    Miles, Evan; Willis, Ian; Arnold, Neil; Pellicciotti, Francesca

    2016-04-01

    Debris-covered glaciers have received renewed interest in recent years in an attempt to improve understanding of climate-glacier interactions in High Mountain Asia. Understanding of key processes occurring in supraglacial ponds has advanced conceptually to include conduit-collapse formation, subaqueous and waterline melting, calving, and englacial filling and drainage. The behaviour of systems of ponds, however, has received little attention, as most process observations have been made on individual features. Several studies have used satellite data to determine pond distributions at a single point in time or their variability across several years or decades. However, no attempt has been made to document the seasonal and inter-annual variability of ponds, even though individual ponds have been observed to fill and drain periodically. We analyse 172 Landsat TM/ETM+ scenes for the period 1999-2013 to identify thawed supraglacial ponds for the debris-covered tongues of five glaciers in the Langtang Valley of Nepal. We apply an advanced atmospheric correction routine (LandCor/6S) and improve upon previous band-ratio and image morphological techniques to identify ponds, then apply this database of identified ponds to: 1) measure the density of supraglacial ponding for five glaciers with differing characteristics, and evaluate the dependency of pond density to those glaciers' characteristics; 2) evaluate the controls that surface gradient and glacier velocity in particular exert on pond occurrence; 3) document the seasonal cycle of pond thawing and formation followed by freezing and draining; 4) document pond persistence, recurrence, and evolution over the 15-year period; and 5) determine if surface ponding has increased over time for the study glaciers. We find high variability between glaciers (0.08-1.69% of debris-covered area during ablation season), related primarily to glacier size, velocity, and surface gradient. At the glacier scale, pond cover is also correlated

  1. The removal of ammonia from sanitary landfill leachate using a series of shallow waste stabilization ponds.

    PubMed

    Leite, V D; Pearson, H W; de Sousa, J T; Lopes, W S; de Luna, M L D

    2011-01-01

    This study evaluated the efficiency of a shallow (0.5 m deep) waste stabilization pond series to remove high concentrations of ammonia from sanitary landfill leachate. The pond system was located at EXTRABES, Campina Grande, Paraiba, Northeast Brazil. The pond series was fed with sanitary landfill leachate transported by road tanker to the experimental site from the sanitary landfill of the City of Joao Pessoa, Paraiba. The ammoniacal-N surface loading on the first pond of the series was equivalent to 364 kg ha(-1) d(-1) and the COD surface loading equivalent to 3,690 kg ha(-1) d(-1). The maximum mean ammonia removal efficiency was 99.5% achieved by the third pond in the series which had an effluent concentration of 5.3 mg L(-1) ammoniacal-N for an accumulative HRT of 39.5 days. The removal process was mainly attributed to ammonia volatilization (stripping) from the pond surfaces as a result of high surface pH values and water temperatures of 22-26°C. Shallow pond systems would appear to be a promising technology for stripping ammonia from landfill leachate under tropical conditions. PMID:21330712

  2. Analysis of storm-water infiltration ponds on the North Carolina Outer Banks

    SciTech Connect

    Chescheir, G.M.; Fipps, G.; Skaggs, R.W.

    1990-09-01

    Increasing development along the North Carolina coast has been linked to the deterioration of water quality in adjacent sounds and estuaries. Degradation of water quality in sounds and estuaries threatens the coastal ecology which provides resources for the area's fishing and tourism industries. The state of N.C. adopted the current Stormwater Runoff Disposal Rules in 1988 requiring stormwater management plans for new development in 20 coastal counties. Stormwater infiltration pond systems are approved by the State as an option for retaining stormwater on the developed site; however, the long-term performance of these systems has not been measured or determined. The study was conducted to monitor the hydrology of stormwater infiltration ponds on the North Carolina barrier islands and to develop a model that continuously simulates the performance of these ponds. The hydrology of two operating infiltration ponds systems was evaluated in an 18-month field study. Rainfall, pond stage, and water table elevations at selected locations were monitored continuously. Water table elevations at additional locations were monitored on a biweekly basis. Soil hydraulic conductivities and soil water characteristic relationships were determined at both field sites. The subsurface geology was described at one site and an aquifer pump test was performed to determine aquifer transmissivity and specific yield. Both of the infiltration ponds in the field studies effectively served their primary purpose of retaining on site the stormwater runoff from the first 38 mm (1.5 in) of rainfall. In nearly every case, the pond seepage rate was sufficient to completely draw down the pond within 5 days. The hydrology of the infiltration ponds at the two research sites was very different.

  3. Water Balance of Shrinking Thermkorst Ponds near Council, Alaska

    NASA Astrophysics Data System (ADS)

    Fraver, M. R.; Hinzman, L. D.; Yoshikawa, K.; Kane, D. L.

    2003-12-01

    Water balances were conducted on a wetland complex near Council, Alaska on the Seward Peninsula during the 2001 and 2002 summers in order to investigate the possibility of groundwater drainage through open taliks. This study is a product of the Arctic Transition in the Land-Atmosphere System (ATLAS) initiation within the Land Atmosphere Ice Interactions (LAII) flux program, created to understand the feedbacks within the land-atmosphere system in arctic regions and to predict reasonable scenarios resulting from future global climate change. The majority of ponds in the Council area are displaying a decreased surface area when compared with aerial photographs from the 1950's, and because the long-term temperature and precipitation data from Nome does not reveal any conclusive trends, the cause of this change is hypothesized to be related to the local permafrost and thermokarst conditions. From permafrost boring data, DC electrical sounding studies, and ground penetrating radar (GPR) surveys, the permafrost in the area is typically 20 to 60 meters thick, and underneath the shrinking thermokarst ponds are large thawed regions (taliks), most of which extend through the local permafrost (open taliks). Downward vertical gradients have been identified in the open taliks, indicating the downward migration of water from the ponds to the subpermafrost groundwater. It was hypothesized that this water loss mechanism is significant in the hydrologic dynamics of the ponds and is related to the recent drying of the ponds. The results of this two-year study, however, demonstrate that evapotranspiration and lateral drainage are capable of accounting for 100% of the observed storage changes.

  4. State-of-the-art review of solar ponds

    NASA Astrophysics Data System (ADS)

    Tolbert, W. A.

    1981-04-01

    This report provides a brief but concise review of solar pond technologies and their potential for application within the military. The report covers salt gradient solar ponds (SGSP), shallow solar ponds (SSP), saltless convecting solar ponds, gel ponds, viscosity stabilized ponds, and membrane ponds. In addition, several criteria were evaluated with respect to solar ponds. These included reliability, maintainability, efficiency, survivability, environmental impact and economics. Research and development requirements and ongoing activities were also summarized. This report documents one of several ongoing state-of-the-art reviews of solar technologies performed by an Air Force liaison office with the Department of Energy.

  5. 33 CFR 117.600 - Lagoon Pond.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Lagoon Pond. 117.600 Section 117.600 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Massachusetts § 117.600 Lagoon Pond. The draw of the Lagoon...

  6. 33 CFR 117.600 - Lagoon Pond.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Lagoon Pond. 117.600 Section 117.600 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Massachusetts § 117.600 Lagoon Pond. The draw of the Lagoon...

  7. 33 CFR 117.600 - Lagoon Pond.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Lagoon Pond. 117.600 Section 117.600 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Massachusetts § 117.600 Lagoon Pond. The draw of the Lagoon...

  8. 33 CFR 117.600 - Lagoon Pond.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Lagoon Pond. 117.600 Section 117.600 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Massachusetts § 117.600 Lagoon Pond. The draw of the Lagoon...

  9. 33 CFR 117.600 - Lagoon Pond.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Lagoon Pond. 117.600 Section 117.600 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Massachusetts § 117.600 Lagoon Pond. The draw of the Lagoon...

  10. Zooplankton succession in fingerling production ponds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Many pond cultured species require a range of zooplankton species for consumption before they can be weaned onto manufactured feed. The widest variety of plankton species develops when empty ponds are filled and fertilized. Use of organic and inorganic fertilizers facilitates the development of ba...

  11. Chemical and biological processes of evaporation ponds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Agricultural evaporation ponds are designed to impound and dissipate saline agricultural drainage water in areas with no opportunities for offsite disposal in the San Joaquin Valley of California. This paper reviews and summarizes research findings on the pond chemistry. Drainage waters in these pon...

  12. 100-D Ponds closure plan. Revision 1

    SciTech Connect

    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.

  13. Par Pond vegetation status Summer 1995 -- Summary

    SciTech Connect

    Mackey, H.E. Jr.; Riley, R.S.

    1996-01-01

    The water level of Par Pond was lowered approximately 20 feet in mid-1991 in order to protect downstream residents from possible dam failure suggested by subsidence on the downstream slope of the dam and to repair the dam. This lowering exposed both emergent and nonemergent macrophyte beds to drying conditions resulting in extensive losses. A survey of the newly emergent, shoreline aquatic plant communities of Par Pond began in June 1995, three months after the refilling of Par Pond to approximately 200 feet above mean sea level. These surveys continued in July, September, and late October, 1995. Communities similar to the pre-drawdown, Par Pond aquatic plant communities are becoming re-established. Emergent beds of maidencane, lotus, waterlily, and watershield are extensive and well developed. Cattail occurrence continued to increase during the summer, but large beds common to Par Pond prior to the drawdown have not formed. Estimates from SPOT HRV, remote sensing satellite data indicated that as much as 120 hectares of emergent wetlands vegetation may have been present along the Par Pond shoreline by early October, 1995. To track the continued development of macrophytes in Par Pond, future surveys throughout 1996 and 1997, along with the continued evaluation of satellite data to map the areal extent of the macrophyte beds of Par Pond, are planned.

  14. Sydney Tar Ponds Remediation: Experience to China

    ERIC Educational Resources Information Center

    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…

  15. Bacterial Bioaugmentation of Channel Catfish Ponds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Twelve, 0.1-ha earthen ponds at Stoneville, Mississippi were used in a 2-year, double-blind study of the effects of a Bacillus-based bacterial bioaugmentation product on water quality and production of channel catfish Ictalurus punctatus. Each year, six ponds were treated weekly with the microbial p...

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

    PubMed

    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. PMID:25906355

  17. Intermediate Pond Sizes Contain the Highest Density, Richness, and Diversity of Pond-Breeding Amphibians

    PubMed Central

    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. PMID:25906355

  18. Insights into the Effects of the Spatial Configuration of Flood Retention Ponds on Flood Frequency

    NASA Astrophysics Data System (ADS)

    Ayalew, T. B.; Krajewski, W. F.; Mantilla, R.

    2014-12-01

    As the construction of large dams for flood control purposes becomes no longer attractive due to their high cost and adverse environmental impacts, the use of spatially distributed flood retention ponds in both urban and rural settings is becoming an alternative flood management practice. However, little is known about how the spatial configuration of ponds and their storage and release capacities relative to their location in the drainage network affect the flood frequency at different locations in the catchment. In this study, we investigate this issue using a continuous simulation approach where a randomly generated rainfall time series is used to derive a hydrologic model that mimics the translation, aggregation, and attenuation of flows along the drainage network. We began by investigating how flood retention ponds that are configured either in series or in parallel affect the flood frequency using a hypothetical catchment (A=30 km2) whose drainage network is idealized using the deterministic Mandelbrot-Viseck tree. Our results show that ponds that are configured in parallel and placed at the upstream section of the basin offer a better peak flood reduction than ponds that are either configured in series along the main stem of the drainage network or a single bigger pond that is located at the outlet. The results also show that, for ponds that are configured in series, emptying the upstream dam first offers better regulation of flood peaks than emptying the downstream pond first. Moreover, our results show that, when the two ponds that are configured in series have different storage capacities, it is better to put the larger pond in the upstream section of the catchment. We further expanded the analysis to the Soap Creek catchment (A=660 km2) located in southeastern Iowa, and simulated a system of 132 flood retention ponds that have already been built across that catchment. Our results show how these ponds modify the flood frequency at different locations in

  19. CFD analysis of sludge accumulation and hydraulic performance of a waste stabilization pond.

    PubMed

    Alvarado, Andres; Sanchez, Esteban; Durazno, Galo; Vesvikar, Mehul; Nopens, Ingmar

    2012-01-01

    Sludge management in waste stabilization ponds (WSPs) is essential for safeguarding the system performance. Sludge accumulation patterns in WSPs are strongly influenced by the pond hydrodynamics. CFD modeling was applied to study the relation between velocity profiles and sludge deposition during 10 years of operation of the Ucubamba WSP in Cuenca (Ecuador). One tracer experiment was performed and three sludge accumulation scenarios based on bathymetric surveys were simulated. A residence time distribution (RTD) analysis illustrated the decrease of residence times due to sludge deposition. Sludge accumulation rates were calculated. The influence of flow pattern on the sludge deposition was studied, enabling better planning of future pond operation and desludging. PMID:23032767

  20. Carbonate deposition on tail feathers of ruddy ducks using evaporation ponds

    USGS Publications Warehouse

    Euliss, N.H., Jr.; Jarvis, R.L.; Gilmer, D.S.

    1989-01-01

    Substantial carbonate deposits were observed on rectrices of Ruddy Ducks (Oxyura jamaicensis) collected during 1982-1984 on evaporation ponds in the San Joaquin Valley, California. Carbonate deposits were composed of about 75% aragonite and 25% calcite, both polymorphous forms of CaCO3. Significantly more carbonate deposits were observed on Ruddy Ducks as length of exposure to agricultural drain water increased, during the 1983-1984 field season when salt concentrations in the ponds were higher, and in certain evaporation-pond systems.

  1. Long-Term Hydrological Changes of Coastal Arctic Tundra Ponds in Drained Thaw Lake Basins

    NASA Astrophysics Data System (ADS)

    Andresen, C. G.; Lougheed, V.

    2013-12-01

    Given the dominance of these ponds in the tundra landscape, documenting long-term changes in these aquatic systems is essential to understand carbon and energy balance, trophic energy flow, and biodiversity for the Arctic. The combination of remote sensing using historical imagery, as well as rare historical data from the International Biological Program, provides a unique opportunity for understanding long-term changes in hydrology, chemistry and biology of these significant freshwater environments. To assess the changes in pond area and abundance in 22 drained thaw-lake basins (DTLB) across the Barrow Peninsula over the past 60 years, we utilized historic aerial imagery from USGS archives (1948) and modern high-resolution Quickbird (2002, 2008, 2010). Age classification of DTLB was based on Hinkel et al 2003. We compared water temperature, active layer thickness, and aboveground biomass of these systems to historical datasets compiled in the Limnology of Tundra Ponds' by Hobbie et al 1975. We observed an overall decrease of 28% in pond area and 19% decrease in pond number, where smaller ponds (<100m2) had the highest change. These losses were coincident with significantly higher air and water temperature and reduced annual rainfall, which has decreased by 2.5 cm over the past 62 years (-0.4mm/yr). Active layer in ponds increased on average by 15cm. Aquatic grasses increased in density and cover in ponds over the past 40 years. Area and number of ponds loss was independent of DTLB age; however, medium-age DTLBs had significantly higher number of new ponds over old and ancient-age basins. While we observe new ponds due to thaw lake processes, climate seems to be having a stronger effect on these systems by reducing the overall inundated area and pond number in these basins. Increased evaporation due to warmer and longer summers, permafrost degradation, transpiration from encroaching aquatic grasses and changes in precipitation patterns are likely the current major

  2. Proposal to characterise legacy Sellafield ponds using SONAR and RadLine™.

    PubMed

    Reddy, Sarah F; Monk, Stephen D; Nye, Daniel W; Colling, Bethany R; Stanley, Steven J

    2012-07-01

    Sellafield Nuclear Reprocessing Plant in Cumbria contains storage ponds built in the 1950s which was originally intended to hold spent nuclear fuel for reprocessing, and eventual production of weapons grade plutonium. Parts of the spent fuel have corroded; some are buried under a layer of sediment or intertwined with other debris and removal and destruction of this nuclear waste is not a trivial task due to elevated radiation levels. We propose a system in collaboration with the National Nuclear Laboratory (NNL) to characterise the ponds using a system containing three main parts; an ultrasonic SONAR system used to physically map the pond, scintillator based radiation detector (known as RadLine™) used to map the pond from a radiation point of view, and bespoke software intended to combine the physical and radiation plots of this environment to create an overall 3D source map. PMID:22698817

  3. Seasonal patterns of activity and community structure in an amphibian assemblage at a pond network with variable hydrology

    NASA Astrophysics Data System (ADS)

    Vignoli, Leonardo; Bologna, Marco A.; Luiselli, Luca

    2007-03-01

    We studied community structure and seasonal activity patterns in a system of four ponds with seasonally-variable hydrology at a Mediterranean area in central Italy. We used a set of field methods to assess species presence and relative frequency of observation. The network of ponds was inhabited by six species of amphibians, two salamanders and four frogs. The breeding phenology of the six species did not vary remarkably among ponds, but there were significant differences among species in use of ponds. Factorial analysis of pond similarity drawn from percentage composition of the amphibian fauna, revealed that each of the four ponds was treatable as independent units, with no influence of relative inter-pond distance. PCA analysis allowed us to spatially arrange the amphibian species into three main groups: two were monospecific groups (i.e., Triturus vulgaris and Bufo bufo) and the third consisted of those species that selected not only the largest-deepest ponds, but also the ephemeral ones (i.e., Triturus carnifex, Hyla intermedia, the green frogs and Rana dalmatina). Our results suggest that the inter-pond differences in riparian vegetation, water depth, aquatic vegetation structure/abundance, and soil composition may produce differences among pond ecological characteristics (i.e., water turbidity and temperature, shelter availability, abundance of oviposition micro-sites), which may in turn influence different patterns of use by amphibians. To our knowledge, this is the first study emphasizing the potential role of heterochrony in the maintenance of a high species richness in Mediterranean amphibian communities. Preservation of freshwater vertebrate biodiversity requires management and protection not only of the main ponds and water bodies but also the temporary and ephemeral shallow ponds.

  4. HRE-Pond Cryogenic Barrier Technology Demonstration: Pre- and Post-Barrier Hydrologic Assessment

    SciTech Connect

    Moline, G.R.

    1999-06-01

    The Homogeneous Reactor Experiment (HRE) Pond is the site of a former impoundment for radioactive wastes on the Oak Ridge Reservation (ORR) in east Tennessee. The pond received radioactive wastes from 1957 to 1962, and was subsequently drained, filled with soil, and covered with an asphalt cap. The site is bordered to the east and south by an unnamed stream that contains significant concentrations of radioactive contaminants, primarily {sup 90}Sr. Because of the proximity of the stream to the HRE disposal site and the probable flow of groundwater from the site to the stream, it was hypothesized that the HRE Pond has been a source of contamination to the creek. The HRE-Pond was chosen as the site of a cryogenic barrier demonstration to evaluate this technology as a means for rapid, temporary isolation of contaminants in the type of subsurface environment that exists on the ORR. The cryogenic barrier is created by the circulation of liquid CO{sub 2} through a system of thermoprobes installed in boreholes which are backfilled with sand. The probes cool the subsurface, creating a vertical ice wall by freezing adjacent groundwater, effectively surrounding the pond on four sides. The purpose of this investigation was to evaluate the hydrologic conditions within and around the pond prior to, during, and after the cryogenic barrier emplacement. The objectives were (1) to provide a hydrologic baseline for post-banner performance assessment, (2) to confirm that the pond is hydraulically connected to the surrounding sediments, (3) to determine the likely contaminant exit pathways from the pond, and (4) to measure changes in hydrologic conditions after barrier emplacement in order to assess the barrier performance. Because relatively little information about the subsurface hydrology and the actual configuration of the pond existed, data from multiple sources was required to reconstruct this complex system.

  5. Hydrology and chemistry of groundwater and seasonal ponds in the Atlantic Coastal Plain in Delaware, USA

    NASA Astrophysics Data System (ADS)

    Phillips, Patrick J.; Shedlock, Robert J.

    1993-01-01

    The hydrochemistry of small seasonal ponds was investigated by studying relations between ground-water and surface water in a forested Coastal Plain drainage basin. Observation of changes in the water table in a series of wells equipped with automatic water-level recorders showed that the relation between water-table configuration and basin topography changes seasonally, and particularly in response to spring recharge. Furthermore, in this study area the water table is not a subdued expression of the land surface topography, as is commonly assumed. During the summer and fall months, a water-table trough underlies sandy ridges separating the seasonal ponds, and maximum water-table altitudes prevail in the sediments beneath the dry pond bottoms. As the ponds fill with water during the winter, maximum water-table altitudes shift to the upland-margin zone adjacent to the seasonal ponds. Increases in pond stage are associated with the development of transient water-table mounds at the upland-margin wells during the spring. The importance of small local-flow systems adjacent to the seasonal ponds also is shown by the similarities in the chemistry of the shallow groundwater in the upland margin and water in the seasonal ponds. The upland margin and surface water samples have low pH (generally less than 5.0), and contain large concentrations of dissolved aluminum (generally more than 100 μg 1 -1), and low bicarbonate concentrations (2 mg l 4 or less). In contrast, the parts of the surficial aquifer that do not experience transient mounding have higher pH and larger concentrations of bicarbonate. These results suggest that an understanding of the hydrochemistry of seasonally ponded wetlands requires intensive study of the adjacent shallow groundwater-flow system.

  6. Sodium-based flue gas desulfurization sludge disposal ponds. Final report

    SciTech Connect

    Ainsworth, C.C.; Rai, D.; Smith, S.C.; Felmy, A.R.; Amonette, J.E.; Resch, C.T.

    1994-04-01

    Two flue gas desulfurization (FGD) sludge disposal ponds, each receiving sludge from a different sodium (Na)-based FGD scrubbing system, at a subbituminous coal-fired power plant were investigated. Samples of pond and pore waters, and sludge solids from selected ponds were obtained to characterize pond biogeochemistry to identify common or distinguishing reactions that affect disposal of FGD sludge and to evaluate possible causes for the different H{sub 2}S{sub (g)} emissions observed for the two pond systems. Very high levels of total dissolved solids characterized both Na-based FGD scrubber material used, the biogeochemistry of the sludge disposal ponds is very similar, and certain biogeochemical reactions are generic to controlling the leachate chemistry of FGD ponds. Dissimilatory microbial SO{sub 4}{sup 2{minus}} reduction to sulfide is present in both ponds and reacts with various solution-phase heavy metals (e.g., Cd, Cu, Fe, Ni, Pb, and Zn) to form low-solubility sulfide minerals, and hence, aqueous concentrations of these metals are at or near the analytical detection limits. The H{sub 2}S{sub (g)} emissions result from H{sub 2}S{sub (g)} generation in the sediments and diffusion up through the water column. Oxidation of H{sub 2}S{sub (g)} as it migrates up the water column is dependent on (1) the chemical oxygen demand of the pond waters, (2) the pH and hence speciation of the H{sub 2}S, (3) the depth of the water, and (4) the temperature and salinity of the water.

  7. Don Quixote Pond Sediments: Surface and Subsurface Chemistry and Mineralogy

    NASA Astrophysics Data System (ADS)

    Englert, P. A. J.; Bishop, J. L.; Patel, S.; Gibson, E. K.; Koeberl, C.

    2014-12-01

    Don Quixote Pond, like Don Juan Pond in the South Fork of Wright Valley, Antarctica, is a model for calcium and chlorine weathering and distribution on Mars. It is located in the western part of the North Fork about 100 m above Mean Seawater Level; its brine is seasonally frozen [1]. Field observations show zones of discoloration which grow lighter with distance from the pond edges. Four sediment cores, a set of radial surface samples, special surface samples, and samples of local rocks were obtained [2]. We report on chemical and mineral analyses of traverse samples and on two cores. Core DQ20 is a northeastern shoreline core. Its soluble salt concentration exceeds 200 micromoles/g in the top 5 cm, and then falls to less than 70 micromoles/g at the permafrost depth of 15 cm. These concentrations are low when compared to similarly positioned locations at Don Juan Pond and to cores from Prospect Mesa close to Lake Vanda, Wright Valley. Halite, soda niter, tachyhydrite and/bischovite are suggested from the ionic molar relationships Measured halite concentrations of surface samples, collected along a traverse of 35 m from the pond outwards, range from over 5% to trace amounts, decreasing with distance. Gypsum is also present in almost all of these samples ranging from 0.2% to 2.6%, but does not exhibit a trend. However, in core DQ35, located at a distance of 15 m along the traverse, gypsum decreases from 2.5% to 0.6% from the surface to the permafrost depth of 12 cm. While DQ35 and radial samples show high quartz and albite abundance, samples that contained visible encrustations and evaporites are low in these minerals and rich in highly diverse alteration products. Don Juan Basin ponds may have formed by a complex surface water mobilization of weathering products [3] and local groundwater action [4,5]. In contrast, Don Quixote pond mineralogy and chemistry may be consistent with a less complex shallow and deep groundwater system origin [1]. [1] Harris H

  8. Benthic Primary Production in a Saltmarsh Pond: Insights from Fluxes of Dissolved Inorganic Carbon and Oxygen

    NASA Astrophysics Data System (ADS)

    Karolewski, J. S.; Stanley, R. H.; Howard, E. M.; Spivak, A. C.

    2014-12-01

    Salt marshes are important carbon sinks that exist at continental margins and act as mediators in the exchange of nutrients and carbon between terrestrial and marine environments. Within salt marshes, 10-20% of total surface area is covered by marshtop ponds. The fractional area of marshtop ponds is predicted to increase as sea level rises. Despite their potential importance, the balance between autotrophic and heterotrophic processes within such ponds remain poorly understood. To quantify the balance of metabolic fluxes within salt marsh ponds, chemical fluxes of dissolved inorganic carbon (DIC) and dissolved oxygen (DO) were measured in July, 2014 in benthic flux chambers inserted into a salt marsh pond in the Plum Island Estuary Long-Term Ecosystem Research (PIE-LTER) site. Light and dark chambers were used to enable separation of rates of photosynthesis and respiration. Separate chambers were used to enclose sediment covered by primarily benthic microalgae and primarily benthic macroalgae. Net ecosystem metabolism in the microalgae was ~10 and in the macroalgae ~15 mmol C/m2/hour. Respiration rates were ~10 mmol C/m2/ hour for both microalgae and macroalgae. The resulting fluxes of net ecosystem production in the ponds will be compared with overall marsh net ecosystem flux as measured by an eddy flux tower that was located 100 meters from the pond. Additionally, concurrent measurements of DIC and DO allow quantification of the C:O ratio during respiration (i.e. respiratory quotient) in this system.

  9. Nitrogen removal in maturation waste stabilisation ponds via biological uptake and sedimentation of dead biomass.

    PubMed

    Camargo Valero, M A; Mara, D D; Newton, R J

    2010-01-01

    In this work a set of experiments was undertaken in a pilot-scale WSP system to determine the importance of organic nitrogen sedimentation on ammonium and total nitrogen removals in maturation ponds and its seasonal variation under British weather conditions, from September 2004 to May 2007. The nitrogen content in collected sediment samples varied from 4.17% to 6.78% (dry weight) and calculated nitrogen sedimentation rates ranged from 273 to 2868 g N/ha d. High ammonium removals were observed together with high concentrations of chlorophyll-a in the pond effluent. Moreover, chlorophyll-a had a very good correlation with the corresponding increment of VSS (algal biomass) and suspended organic nitrogen (biological nitrogen uptake) in the maturation pond effluents. Therefore, when ammonium removal reached its maximum, total nitrogen removal was very poor as most of the ammonia taken up by algae was washed out in the pond effluent in the form of suspended solids. After sedimentation of the dead algal biomass, it was clear that algal-cell nitrogen was recycled from the sludge layer into the pond water column. Recycled nitrogen can either be taken up by algae or washed out in the pond effluent. Biological (mainly algal) uptake of inorganic nitrogen species and further sedimentation of dead biomass (together with its subsequent mineralization) is one of the major mechanisms controlling in-pond nitrogen recycling in maturation WSP, particularly when environmental and operational conditions are favourable for algal growth. PMID:20182083

  10. Avian communities in baylands and artificial salt evaporation ponds of the San Francisco Bay estuary

    USGS Publications Warehouse

    Takekawa, J.Y.; Lu, C.T.; Pratt, R.T.

    2001-01-01

    San Francisco Bay wetlands, seasonal and tidal marshes between the historic low and high tide lines, are now highly fragmented because of development during the past 150 years. Artificial salt pond systems in the Bay are hypersaline and typically support simple assemblages of algae and invertebrates. In order to establish the value of salt ponds for migratory waterbirds, we used datasets to conduct a meta-analysis of avian communities in the baylands and salt ponds of San Pablo Bay. Fifty-three species of waterbirds in the salt ponds represented six foraging guilds: surface feeders, shallow probers, deep probers, dabblers, diving benthivores and piscivores. The total number of species and the Shannon-Weiner diversity index was higher in baylands than in salt ponds during all four seasons. However, overall bird density (number/ha) was higher in salt ponds compared with baylands in the winter and spring, primarily because of large concentrations of benthivores. Cessation of salt production in 1993 and subsequent reduction in water depth resulted in a decline of some diving duck populations that used the salt ponds.

  11. Ultimate Heat Sink Thermal Performance and Water Utilization: Measurements on Cooling and Spray Ponds

    SciTech Connect

    Athey, G. F.; Hadlock, R. K.; Abbey, O. B.

    1982-02-01

    A data acquisition research program, entitled "Ultimate Heat Sink Performance Field Experiments," has been brought to completion. The primary objective is to obtain the requisite data to characterize thermal performance and water utilization for cooling ponds and spray ponds at elevated temperature. Such data are useful for modeling purposes, but the work reported here does not contain modeling efforts within its scope. The water bodies which have been studied are indicative of nuclear reactor ultimate heat sinks, components of emergency core cooling systems. The data reflect thermal performance and water utilization for meteorological and solar influences which are representative of worst-case combinations of conditions. Constructed water retention ponds, provided with absolute seals against seepage, have been chosen as facilities for the measurement programs; the first pond was located at Raft River, Idaho, and the second at East Mesa, California. The data illustrate and describe, for both cooling ponds and spray ponds, thermal performance and water utilization as the ponds cool from an initially elevated temperature. To obtain the initial elevated temperature, it has been convenient to conduct the measurements at geothermal sites having large supplies and delivery rates of hot geothermal fluid. The data are described and discussed in the text, and presented in the form of data volumes as appendices.

  12. A lipid-accumulating alga maintains growth in outdoor, alkaliphilic raceway pond with mixed microbial communities

    DOE PAGESBeta

    Bell, Tisza A.S.; Prithiviraj, Bharath; Wahlen, Brad D.; Fields, Matthew W.; Peyton, Brent M.

    2016-01-07

    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 (~9.8). An outdoor raceway pond (200 L) was inoculated with C. vulgarismore » and monitored for 10 days and then the culture was transferred to a 2,000 L raceway pond and cultivated for an additional 6 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. As a result, 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 biomass

  13. A Lipid-Accumulating Alga Maintains Growth in Outdoor, Alkaliphilic Raceway Pond with Mixed Microbial Communities

    PubMed Central

    Bell, Tisza A. S.; Prithiviraj, Bharath; Wahlen, Brad D.; Fields, Matthew W.; Peyton, Brent M.

    2016-01-01

    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 (∼9.8). An outdoor raceway pond (200 L) was inoculated with C. vulgaris and monitored for 10 days and then the culture was transferred to a 2,000 L raceway pond and cultivated for an additional 6 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 biomass productivity in an

  14. A Lipid-Accumulating Alga Maintains Growth in Outdoor, Alkaliphilic Raceway Pond with Mixed Microbial Communities.

    PubMed

    Bell, Tisza A S; Prithiviraj, Bharath; Wahlen, Brad D; Fields, Matthew W; Peyton, Brent M

    2015-01-01

    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 (∼9.8). An outdoor raceway pond (200 L) was inoculated with C. vulgaris and monitored for 10 days and then the culture was transferred to a 2,000 L raceway pond and cultivated for an additional 6 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 biomass productivity in an open

  15. Stable density stratification solar pond

    NASA Technical Reports Server (NTRS)

    Lansing, F. L. (Inventor)

    1985-01-01

    A stable density-stratification solar pond for use in the collection and storage of solar thermal energy including a container having a first section characterized by an internal wall of a substantially cylindrical configuration and a second section having an internal wall of a substantially truncated conical configuration surmounting the first section in coaxial alignment therewith, the second section of said container being characterized by a base of a diameter substantially equal to the diameter of the first section and a truncated apex defining a solar energy acceptance opening is discussed. A body of immiscible liquids is disposed within the container and comprises a lower portion substantially filling the first section of the container and an upper portion substantially filling the second section of the container, said lower portion being an aqueous based liquid of a darker color than the upper portion and of a greater density. A protective cover plate is removably provided for covering the acceptance opening.

  16. 40 CFR 265 interim-status ground-water monitoring plan for the 2101-M pond

    SciTech Connect

    Chamness, M.A.; Luttrell, S.P.; Dudziak, S.

    1989-03-01

    This report outlines a ground-water monitoring plan for the 2101-M pond, located in the southwestern part of the 200-East Area on the Hanford Site in south-central Washington State. It has been determined that hazardous materials may have been discharged to the pond. Installation of an interim-status ground-water monitoring system is required under the Resource Conservation and Recovery Act to determine if hazardous chemicals are moving out of the pond. This plan describes the location of new wells for the monitoring system, how the wells are to be completed, the data to be collected, and how those data can be used to determine the source and extent of any ground-water contamination from the 2101-M pond. Four new wells are planned, one upgradient and three downgradient. 35 refs., 12 figs., 9 tabs.

  17. Photosynthesis and fish production in culture ponds

    SciTech Connect

    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.

  18. ANL-W 779 pond seepage test

    SciTech Connect

    Braun, D.R.

    1992-11-01

    The ANL-W 779 sanitary wastewater treatment ponds are located on the Idaho National Engineering Laboratory (INEL), north of the Argonne National Laboratory -- West (ANL-W) site A seepage test was performed for two Argonne National Laboratory -- West (ANL-W) sanitary wastewater treatment ponds, Facility 779. Seepage rates were measured to determine if the ponds are a wastewater land application facility. The common industry standard for wastewater land application facilities is a field-measured seepage rate of one quarter inch per day or greater.

  19. Tailings Pond Characterization And Designing Through Geophysical Surveys In Dipping Sedimentary Formations

    NASA Astrophysics Data System (ADS)

    Muralidharan, D.; Andrade, R.; Anand, K.; Sathish, R.; Goud, K.

    2009-12-01

    two magnetic profiles inside the tailings pond and surrounding areas on the southern part of the tailings pond enabled in identifying two parallel east-west intrusive bodies forming the impermeable boundary for the tailings pond. The shallow seismic refraction and the geophysical studies in and around the proposed tailings pond brought out the suitability of the site, even when the toxic elements percolates through the subsurface formations in to the groundwater system, the existence of dykes on either side of the proposed ponding area won’t allow the water to move across them thus by restricting the contamination within the tailings pond area. Similarly, the delineation of a fault zone within the tailings pond area helped in shifting the proposed dam axis of the pond to avoid leakage through the fault zone causing concern to environment pollution.

  20. Modelling the Hydrological Performance of Stormwater Management Retention Ponds in Scotland

    NASA Astrophysics Data System (ADS)

    Morgan, C. T.; Wallis, S. G.; Lunn, R. J.; Heal, K.

    2004-12-01

    The work presented here is part of a wider modelling study into the long-term performance of Sustainable Urban Drainage Systems in Scotland, a stormwater management technique employed by the Scottish Environment Protection Agency to protect watercourses from flooding and water quality deterioration. In particular, the study aims to predict how retention ponds perform under varying inflow conditions and climate change scenarios to assess the long-term impact of this form of stormwater management on Scotland's future water resources. A suite of simulations was conducted to explore the flow attenuation characteristics of conical retention ponds that have outflows controlled by triangular notch weirs. The inflows were represented as triangular hydrographs using a range of peak flows. Optimum flow attenuation occurs when peak outflow is reduced and hydrograph time lags are prolonged. Analysis of the results has shown that the Temporary Storage Volume available in the retention pond during any given storm exercises a critical control on flow attenuation performance of the pond. Factors which increase Temporary Storage Volume such as increasing pond radius, decreasing water level at the start of a storm, decreasing pond side slope gradient and increasing weir crest elevation lead to a marked improvement in pond flow attenuation performance. Conversely, factors which decrease Temporary Storage Volume result in poor flow attenuation performance. These simulations also demonstrate the secondary control that weir angle has on flow attenuation performance through its influence on the Dynamic Storage Volume, which is only effective once outflow through the weir has begun. Larger weir angles reduce the flow attenuation performance of ponds; however caution must be exercised in using smaller weir angles, which despite improving performance, may lead to an increased risk of overtopping. Other simulations show that ponds suffer a reduction in performance when subject to larger

  1. Multi-stage ponds-wetlands ecosystem for effective wastewater treatment*

    PubMed Central

    Peng, Jian-feng; Wang, Bao-zhen; Wang, Lin

    2005-01-01

    The performance of the Dongying multi-stage ponds-wetlands ecosystem was investigated in this work. Study of the removal of different pollutants (BOD5, COD, SS, TP, TN, NH3-N, etc.) in different temperature seasons and different units in this system indicated that effluent BOD5 and SS were constant to less than 11 mg/L and 14 mg/L throughout the experimental processes; but that the removal efficiencies of pollutants such as TP, TN, NH3-N, COD varied greatly with season. The higher the temperature was, the higher was the observed removal in this system. Additionally, each unit of the system functioned differently in removing pollutants. BOD5 and SS were mainly removed in the first three units (hybrid facultative ponds, aeration ponds and aerated fish ponds), whereas nitrogen and phosphates were mainly removed in hydrophyte ponds and constructed reed wetlands. The multi-stage ponds-wetlands ecosystem exhibits good potential of removing different pollutants, and the effluent quality meet several standards for wastewater reuse. PMID:15822145

  2. 216-U-10 Pond and 216-Z-19 Ditch characterization studies

    SciTech Connect

    Last, G.V.; Duncan, D.W.; Graham, M.J.; Hall, M.D.; Hall, V.W.; Landeen, D.S.; Leitz, J.G.; Mitchell, R.M.

    1994-02-01

    The chemical, reprocessing of spent nuclear fuels at the US Department of Energy`s Hanford Site has generated large volumes of radioactive liquid effluents. The majority of these effluents have been used strictly for cooling or other supportive functions and have been discharged to ditches and ponds. The 216-U-10 Pond and 216-Z-19 Ditch are two such disposal facilities. These facilities are components of an integrated system of ditches, ponds, and overflow facilities collectively referred to as the U-Pond disposal system. The U-Pond system has been used since 1943 and has received a large variety of radioisotopes from several sources. This study covered tho major aspects of the environment, including wind resuspension, biological uptake and transport, geologic distribution in surface and subsurface sediments, and ground-water impacts. The long-term use of U-Pond and the Z-19 Ditch has resulted in the localized accumulation of transuranic and fission product inventories as a result of sorption and filtration of particulates onto the uppermost sediments.

  3. "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."

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  4. Renewable Water: Direct Contact Membrane Distillation Coupled With Solar Ponds

    NASA Astrophysics Data System (ADS)

    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

  5. Determining the Population Size of Pond Phytoplankton.

    ERIC Educational Resources Information Center

    Hummer, Paul J.

    1980-01-01

    Discusses methods for determining the population size of pond phytoplankton, including water sampling techniques, laboratory analysis of samples, and additional studies worthy of investigation in class or as individual projects. (CS)

  6. This Pond Is Not for Ducks.

    ERIC Educational Resources Information Center

    American School and University, 1980

    1980-01-01

    The latest development in solar energy is a four-acre pond planned for Clark College in Vancouver (Washington). Filled with brine, it will serve both as collector and heat storage tank for the entire campus. (Author)

  7. Wintertime Emissions from Produced Water Ponds

    NASA Astrophysics Data System (ADS)

    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

  8. Material Selection Considerations for Solar Ponds

    NASA Technical Reports Server (NTRS)

    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.

  9. Radioecological implications of the Par Pond drawdown

    SciTech Connect

    Hickey, H.; Whicker, F.W.

    1991-12-05

    The drawdown of the Par Pond reservoir created dramatic alterations in this formerly stable lentic ecosystem. In addition, the radiation environment at Par Pond has changed significantly because of the exposure of Cesium 137-contaminated sediments and the appearance of new transport pathways to the terrestrial environment. In response to this situation, SREL was asked to study the radioecological implications of the reservoir drawdown. This report contains the objectives, methods, and results of the SREL study.

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

    SciTech Connect

    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.

  11. Inverse dependency of particle residence times in ponds to the concentration of phosphate, the limiting nutrient.

    PubMed

    Roberts, Kimberly A; Santschi, Peter H

    2004-01-01

    234Th, a commonly used short-lived particle-reactive tracer in marine systems, was measured in three different holding pond series at the Rocky Flats Environmental Technology Site (RFETS), Colorado, along with its parent nuclide 238U, to determine steady-state residence times of particle-reactive actinides such as Pu, and of particles. Series B ponds, which received industrial effluent that includes ortho-phosphate (PO4) and actinides, differed from series A and C ponds, which did not. This difference was also evident in the calculated particle residence times, which were <1 day for the ponds B4 and B5, where PO4 concentrations were higher (1.4 and 1.8 mg/l), and 3 and 3.4 days for ponds A3 and C2, respectively, where ortho-phosphate concentrations were lower (<0.1 mg/l). Particle residence times thus showed an inverse relationship with the concentration of ortho-phosphate, the limiting nutrient in fresh water systems. The same relationship to the concentration of ortho-phosphate or any of the other nutrient elements was not evident for the residence times of dissolved 234Th, which ranged between 0.1 and 2 days. This can be attributed to higher concentrations of dissolved and particulate ligands with greater binding potential for actinides such as four-valent Th and Pu in ponds with higher ortho-phosphate concentrations. Regardless of actual ortho-phosphate concentration, however, at water residence (holding) times of 1 month in these ponds, particles and associated actinides would be expected to be completely removed from the pond water to sediments. PMID:15261419

  12. Prokaryotic Community Diversity Along an Increasing Salt Gradient in a Soda Ash Concentration Pond.

    PubMed

    Simachew, Addis; Lanzén, Anders; Gessesse, Amare; Øvreås, Lise

    2016-02-01

    The effect of salinity on prokaryotic community diversity in Abijata-Shalla Soda Ash Concentration Pond system was investigated by using high-throughput 16S rRNA gene 454 pyrosequencing. Surface water and brine samples from five sites spanning a salinity range of 3.4 % (Lake Abijata) to 32 % (SP230F, crystallizer pond) were analyzed. Overall, 33 prokaryotic phyla were detected, and the dominant prokaryotic phyla accounted for more than 95 % of the reads consisting of Planctomycetes, Bacteroidetes, candidate division TM7, Deinococcus-Thermus, Firmicutes, Actinobacteria, Proteobacteria, and Euryarchaeota. Diversity indices indicated that operational taxonomic unit (OTU) richness decreases drastically with increasing salinity in the pond system. A total of 471 OTUs were found at 3.4 % salinity whereas 49 OTUs were detected in pond SP211 (25 % salinity), and only 19 OTUs in the crystallization pond at 32 % salinity (SP230F). Along the salinity gradient, archaeal community gradually replaced bacterial community. Thus, archaeal community accounted for 0.4 % in Lake Abijata while 99.0 % in pond SP230F. This study demonstrates that salinity appears to be the key environmental parameter in structuring the prokaryotic communities of haloalkaline environments. Further, it confirmed that the prokaryotic diversity in Lake Abijata is high and it harbors taxa with low or no phylogenetic similarities to existing prokaryotic taxa and thus represents novel microorganisms. PMID:26408190

  13. Sewage reuse for aquaculture after treatment in oxidation and duckweed pond.

    PubMed

    Ghangrekar, M M; Kishor, N; Mitra, A

    2007-01-01

    The benefits of treating sewage by pond systems offer, through a simple and low-cost technology, social and commercial benefits, from the waste raw materials. The objective of this work was to demonstrate an effective treatment of the sewage by using natural treatment systems, and use of treated wastewater for aquaculture. The study was conducted for the sewage generated from the IIT Kharagpur campus. After characterization of the sewage, laboratory scale experiments were conducted for treatment using oxidation pond and duckweed pond. Survival and growth of fishes were observed in the experimental ponds using treated sewage. Based on the experimental results, full-scale treatment plant was designed to meet the aquaculture water quality. From the economics of the proposed full-scale plant, and utilization of the treated sewage for aquaculture, it is estimated that, the amount of Rs. 20,0000 can be generated every year. This amount recovered from the aquaculture will be more than the operating cost of the treatment plant, hence, making the operation of sewage treatment plant self sufficient. Use of a UASB reactor as the first stage treatment before sewage passes to the oxidation pond, can be a more attractive alternative because of less land requirement as compared to the oxidation pond alone, and additional land can be made available for aquaculture to increase revenue. PMID:17591210

  14. Phytoplankton as bioindicator for waste stabilization ponds.

    PubMed

    Amengual-Morro, Caterina; Moyà Niell, Gabriel; Martínez-Taberner, Antoni

    2012-03-01

    Waste stabilization ponds are an appropriate technology for domestic onsite wastewater treatment. It is a low-cost technology, requires low maintenance, is highly efficient, mostly natural and remarkably sustainable. In facultative ponds, the existence of an algal population is very important for the stability of the symbiotic relation with aerobic bacteria. The aim of this work is to determine the pattern of microalgae in the facultative and maturation ponds to obtain information for the operation and maintenance work. The important parameters for phytoplankton measured in this study are the organic load, temperature, light penetration, dissolved oxygen and nutrients. Methodology consists in: analysis of main water quality parameters, plankton taxonomic determination and abundance calculation related with the maintenance operations. Results show that cyanobacteria are present in under-loaded conditions and chlorophyceae are present when the pond is overloaded. Using this methodology over time we can obtain a year round pattern to use the phytoplankton as a bioindicator of the pond's conditions. Our conclusion is that the phytoplankton determination and density can be used to know the pond's performance and help the operation and maintenance tasks. PMID:21820796

  15. Analysis of seepage from a pond

    NASA Astrophysics Data System (ADS)

    Mishra, Govinda C.; Saha, Amitava; Kansal, Mitthan L.; Gupta, Ravi P.

    2011-05-01

    A semi-analytical solution has been derived for predicting the time of emptying a pond due to seepage. The time for the seeping water to reach the water table since the pond was initially filled has been calculated applying the Green-Ampt infiltration theory. The recharge rate after the wetting front joins the water table has been computed using a non-linear relationship between seepage head and recharge rate proposed by earlier investigators. The maximum rise in the water table beneath the center of the pond consequent to the time-varying recharge is calculated applying kernel coefficients obtained from solution of the linearized Boussinesq equation. It was observed that a pond with 50-m initial diameter at the water surface and 3-m maximum depth of water is dry after 168 days, where the subsoil is sandy clay. If the subsoil happens to be clay, the depth of water in the pond at the end of 9 months, i.e., after completion of the non-monsoon period, is 0.62 m. The maximum mound heights beneath the pond for constant recharge rate and uniform recharging area calculated from the present solution compare well with existing numerical as well as analytical solutions.

  16. Pond culture of seaweed Sargassum hemiphyllum in southern China

    NASA Astrophysics Data System (ADS)

    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.

  17. Analysis of changes in farm pond network connectivity in the peri-urban landscape of the Taoyuan area, Taiwan.

    PubMed

    Huang, Shu-Li; Lee, Ying-Chieh; Budd, William W; Yang, Min-Chia

    2012-04-01

    The farm pond system for irrigation is the most prominent feature in the Taoyuan area, Taiwan, giving the region a unique landscape and hydrological character. Although this area had more than 3,290 ponds in the 1970s, fewer than 1,800 now remain. This study analyzes changes in irrigation farm ponds and the canal network landscape in the Taoyuan area. The spatial and temporal changes to ponds and the canal network on the Taoyuan plain were examined graphically for each spatial unit (2,765 m × 2,525 m) using aerial photographs for 1979 and 2005. Landscape metrics were calculated to analyze landscape change associated with increased urbanization. Landscape indices of connectivity and circuitry were utilized to describe changes in the configuration of ponds and canal networks. The total length of canals and total number of ponds in the study area decreased significantly during 1979-2005. The average values of connectivity indices (γ- and α-index) also decreased during 1979-2005, reflecting degradation of canal networks due to urban sprawl. A multivariate technique was applied to portion the study area into three zones according to changes to land cover, ponds, and canal networks. The effects of urban sprawl on the spatial pattern of ponds and canal networks are discussed. PMID:22366919

  18. Analysis of Changes in Farm Pond Network Connectivity in the Peri-Urban Landscape of the Taoyuan Area, Taiwan

    NASA Astrophysics Data System (ADS)

    Huang, Shu-Li; Lee, Ying-Chieh; Budd, William W.; Yang, Min-Chia

    2012-04-01

    The farm pond system for irrigation is the most prominent feature in the Taoyuan area, Taiwan, giving the region a unique landscape and hydrological character. Although this area had more than 3,290 ponds in the 1970s, fewer than 1,800 now remain. This study analyzes changes in irrigation farm ponds and the canal network landscape in the Taoyuan area. The spatial and temporal changes to ponds and the canal network on the Taoyuan plain were examined graphically for each spatial unit (2,765 m × 2,525 m) using aerial photographs for 1979 and 2005. Landscape metrics were calculated to analyze landscape change associated with increased urbanization. Landscape indices of connectivity and circuitry were utilized to describe changes in the configuration of ponds and canal networks. The total length of canals and total number of ponds in the study area decreased significantly during 1979-2005. The average values of connectivity indices (γ- and α-index) also decreased during 1979-2005, reflecting degradation of canal networks due to urban sprawl. A multivariate technique was applied to portion the study area into three zones according to changes to land cover, ponds, and canal networks. The effects of urban sprawl on the spatial pattern of ponds and canal networks are discussed.

  19. Comparison of litter decomposition in a natural versus coal-slurry pond reclaimed as a wetland

    USGS Publications Warehouse

    Taylor, J.; Middleton, B.A.

    2004-01-01

    Decomposition is a key function in reclaimed wetlands, and changes in its rate have ramifications for organic-matter accumulation, nutrient cycling, and production. The purpose of this study was to compare leaf litter decomposition rates in coal-slurry ponds vs. natural wetlands on natural floodplain wetlands in Illinois, USA. The rate of decomposition was slower in the natural wetland vs. the coal pond (k=0.0043??0.0008 vs. 0.0066??0.0011, respectively); the soil of the natural wetland was more acidic than the coal pond in this study (pH=5.3 vs. 7.9, respectively). Similarly, higher organic matter levels were related to lower pH levels, and organic matter levels were seven-times higher in the natural wetland than in the coal pond. The coal slurry pond was five years old at the time of the study, while the natural oxbow wetland was older (more than 550 years). The coal-slurry pond was originally a floodplain wetland (slough); the downstream end was blocked with a stoplog structure and the oxbow filled with slurry. The pattern of decomposition for all species in the coal pond was the same as in the natural pond; Potomogeton nodosus decomposed more quickly than Phragmites australis, and both of these species decomposed more quickly than either Typha latifolia or Cyperus erythrorhizos (k=0.0121??0.0008, 0.0051??0.0006, 0.0024??0.0001, 0-0024??0.0004, respectively). Depending on how open or closed the system is to outside inputs, decomposition rate regulates other functions such as production, nutrient cycling, organic-layer accumulation in the soil, and the timing and nature of delivery of detritus to the food chain. ?? 2004 John Wiley and Sons, Ltd.

  20. Nitrification-denitrification in waste stabilisation ponds: a mechanism for permanent nitrogen removal in maturation ponds.

    PubMed

    Camargo Valero, M A; Read, L F; Mara, D D; Newton, R J; Curtis, T P; Davenport, R J

    2010-01-01

    A pilot-scale primary maturation pond was spiked with (15)N-labelled ammonia ((15)NH(4)Cl) and (15)N-labelled nitrite (Na(15)NO(2)), in order to improve current understanding of the dynamics of inorganic nitrogen transformations and removal in WSP systems. Stable isotope analysis of delta(15)N showed that nitrification could be considered as an intermediate step in WSP, which is masked by simultaneous denitrification, under conditions of low algal activity. Molecular microbiology analysis showed that denitrification can be considered a feasible mechanism for permanent nitrogen removal in WSP, which may be supported either by ammonia-oxidising bacteria (AOB) or by methanotrophs, in addition to nitrite-oxidising bacteria (NOB). However, the relative supremacy of the denitrification process over other nitrogen removal mechanisms (e.g., biological uptake) depends upon phytoplanktonic activity. PMID:20220235

  1. Distinct Optical Chemistry of Dissolved Organic Matter in Urban Pond Ecosystems

    PubMed Central

    McEnroe, Nicola A.; Williams, Clayton J.; Xenopoulos, Marguerite A.; Porcal, Petr; Frost, Paul C.

    2013-01-01

    Urbanization has the potential to dramatically alter the biogeochemistry of receiving freshwater ecosystems. We examined the optical chemistry of dissolved organic matter (DOM) in forty-five urban ponds across southern Ontario, Canada to examine whether optical characteristics in these relatively new ecosystems are distinct from other freshwater systems. Dissolved organic carbon (DOC) concentrations ranged from 2 to 16 mg C L-1 across the ponds with an average value of 5.3 mg C L-1. Excitation-emission matrix (EEM) spectroscopy and parallel factor analysis (PARAFAC) modelling showed urban pond DOM to be characterized by microbial-like and, less importantly, by terrestrial derived humic-like components. The relatively transparent, non-humic DOM in urban ponds was more similar to that found in open water, lake ecosystems than to rivers or wetlands. After irradiation equivalent to 1.7 days of natural solar radiation, DOC concentrations, on average, decreased by 38% and UV absorbance decreased by 25%. Irradiation decreased the relative abundances of terrestrial humic-like components and increased protein-like aspects of the DOM pool. These findings suggest that high internal production and/or prolonged exposure to sunlight exerts a distinct and significant influence on the chemistry of urban pond DOM, which likely reduces its chemical similarity with upstream sources. These properties of urban pond DOM may alter its biogeochemical role in these relatively novel aquatic ecosystems. PMID:24348908

  2. Habitat selection by breeding waterbirds at ponds with size-structured fish populations

    NASA Astrophysics Data System (ADS)

    Kloskowski, Janusz; Nieoczym, Marek; Polak, Marcin; Pitucha, Piotr

    2010-07-01

    Fish may significantly affect habitat use by birds, either as their prey or as competitors. Fish communities are often distinctly size-structured, but the consequences for waterbird assemblages remain poorly understood. We examined the effects of size structure of common carp ( Cyprinus carpio) cohorts together with other biotic and abiotic pond characteristics on the distribution of breeding waterbirds in a seminatural system of monocultured ponds, where three fish age classes were separately stocked. Fish age corresponded to a distinct fish size gradient. Fish age and total biomass, macroinvertebrate and amphibian abundance, and emergent vegetation best explained the differences in bird density between ponds. Abundance of animal prey other than fish (aquatic macroinvertebrates and larval amphibians) decreased with increasing carp age in the ponds. Densities of ducks and smaller grebes were strongly negatively associated with fish age/size gradient. The largest of the grebes, the piscivorous great crested grebe ( Podiceps cristatus), was the only species that preferred ponds with medium-sized fish and was positively associated with total fish biomass. Habitat selection by bitterns and most rallids was instead strongly influenced by the relative amount of emergent vegetation cover in the ponds. Our results show that fish size structure may be an important cue for breeding habitat choice and a factor affording an opportunity for niche diversification in avian communities.

  3. Reunification of East and West German School Systems: Longitudinal Multilevel Modeling Study of the Big-Fish-Little-Pond Effect on Academic Self-Concept.

    ERIC Educational Resources Information Center

    Marsh, Herbert W.; Koller, Olaf; Baumert, Jurgen

    2001-01-01

    Used longitudinal data from large cohorts of East and West German students, 2,778 seventh graders in 161 classrooms, to evaluate how the reunification of Germany affects self-concept formation. Results show how system-wide educational policy differences, the initiation of a selective school system and the institutionalization of different…

  4. Dynamics of industrial waste stabilization pond treatment process.

    PubMed

    Veeresh, Mangala; Veeresh, A V; Huddar, Basvaraj D; Hosetti, Basaling B

    2010-10-01

    Waste stabilization pond is an artificial ecosystem; its performance is governed by the nature of the biological communities it supports. These are primarily used as secondary effluent treatment plants to polish the effluents. However, they are also used to treat the raw sewage and industrial effluents. In the present study, the functioning of a waste stabilization pond system from an industrial complex located in Goa was taken up. The raw waste released by the industrial complex and the final effluent released from the stabilization ponds were analyzed for pH, dissolved oxygen (DO), biological oxygen demand, phosphate content, chlorophyll content, and algal diversity and density. Also, the activities of the enzymes catalase and phosphatase were measured. The study was carried out for a period of 1 year and the data covering pre-monsoon, monsoon, and post-monsoon seasons are tabulated. The study revealed that DO, chlorophyll content, and algal count were maximum during pre-monsoon when compared to monsoon and post-monsoon. Similarly, maximum enzymatic activity was recorded during pre-monsoon and also maximum removal of biological oxygen demand and phosphate was recorded during this period than in monsoon and post-monsoon. PMID:19731057

  5. The application of remote sensing in the environmental risk monitoring of tailings pond: a case study in Zhangjiakou area of China

    NASA Astrophysics Data System (ADS)

    Xiao, Rulin; Shen, Wenming; Fu, Zhuo; Shi, Yuanli; Xiong, Wencheng; Cao, Fei

    2012-10-01

    As a kind of huge environmental risk source, tailings pond could cause a huge environmental disaster to the downstream area once an accident happened on it. Therefore it has become one key target of the environmental regulation in china. Especially, recently environmental emergencies caused by tailings pond are growing rapidly in China, the environmental emergency management of the tailings pond has been confronting with a severe situation. However, the regulatory agency is badly weak in the environmental regulation of tailings pond, due to the using of ground surveys and statistics which is costly, laborious and time consuming, and the lacking of strong technical and information support. Therefore, in this paper, according to the actual needs of the environmental emergency management of tailings pond, we firstly make a brief analysis of the characteristics of the tailings pond and the advantages and capability of remote sensing technology, and then proposed a comprehensive and systematic indexes system and the method of environmental risk monitoring of tailings pond based on remote sensing and GIS. The indexes system not only considers factors from the upstream area, the pond area and the downstream area in a perspective of the risk space theory, but also considers factors from risk source, risk receptor and risk control mechanism in a perspective of risk systems theory. Given that Zhangjiakou city has up to 580 tailings pond and is nearly located upstream of the water source of Beijing, so finally we apply the proposed indexes system and method in Zhangjiakou area in China to help collect environmental risk data of tailings pond in that area and find out it works well. Through the use case in Zhajiakou, the technique of using remote sensing to monitor environmental risk of tailings pond is feasible and effective, and would contribute to the establishment of `Space-Ground' monitoring network of tailings pond in future.

  6. Systems and economic analysis of microalgae ponds for conversion of CO{sub 2} to biomass. Quarterly technical progress report, September 1993--December 1993

    SciTech Connect

    Benemann, J.R.; Oswald, W.J.

    1994-01-15

    This report provides an economic analysis and feasibility study for the utilization by microalgal systems of carbon dioxide generated from coal-fired power plants. The resulting biomass could be a fuel substitute for fossil fuels.

  7. SOLPOND: a simulation program for salinity gradient solar ponds

    SciTech Connect

    Henderson, J.; Leboeuf, C.M.

    1980-01-01

    A computer simulation design tool was developed to simulate dynamic thermal performance for salinity gradient solar ponds. Dynamic programming techniques allow the user significant flexibility in analyzing pond performance under realistic load and weather conditions. Finite element techniques describe conduction heat transfer through the pond, earth, and edges. Results illustrate typical thermal performance of salinity gradient ponds. Sensitivity studies of salty pond thermal performance with respect to geometry, load, and optical transmission are included. Experimental validation of the program with an operating pond is also presented.

  8. A review of the salt-gradient solar pond technology

    NASA Technical Reports Server (NTRS)

    Lin, E. I. H.

    1982-01-01

    The state of the salt-gradient solar pond technology is reviewed. Highlights of findings and experiences from existing ponds to data are presented, and the behavior, energy yield, operational features, and economics of solar ponds are examined. It is concluded that salt-gradient solar ponds represent a technically feasible, environmentally benign, and economically attractive energy producing alternative. In order to bring this emerging technology to maturity, however, much research and development effort remains to be undertaken. Specific R&D areas requiring the attention and action of technical workers and decision-makers are discussed, both from the perspectives of smaller, thermally-oriented ponds and larger, electricity generating ponds.

  9. Reunification of East and West German School Systems and the Big Fish Little Pond Effect on Academic Self-Concept. German Reunification and Self-Concept.

    ERIC Educational Resources Information Center

    Marsh, Herbert W.; Koller, Olaf; Baumert, Jurgen

    This paper examines the educational results of the reunification of East and West Germany. Specifically, it discusses what happened to students' self-concept when the East German system, which was highly standardized, was combined with the West German schools, which were highly differentiated and based on achievement. To study this result,…

  10. Comparative performance studies of water lettuce, duckweed, and algal-based stabilization ponds using low-strength sewage.

    PubMed

    Awuah, Esi; Oppong-Peprah, M; Lubberding, H J; Gijzen, H J

    A bench-scale continuous-flow wastewater treatment system comprising three parallel lines using duckweed (Spirodela polyrhiza), water lettuce (Pistia stratiotes), and algae (natural colonization) as treatment agents was set up to determine environmental conditions, fecal coliform profiles and general treatment performance. Each line consisted of four ponds connected in series fed by diluted sewage. Influent and effluent parameters measured included environmental conditions, turbidity, biochemical oxygen demand (BOD), chemical oxygen demand (COD), nitrate, nitrite, ammonia, total phosphorus, fecal coliforms, mosquito larvae, and sludge accumulations. Environmental conditions and fecal coliforms profiles were determined in the sediments (0.63 m), suspensions (0.35 m), and surfaces (0.1 m) of each pond. Acidic conditions were observed in the pistia ponds, neutral conditions in duckweed ponds, and alkaline conditions in algal ponds. Fecal coliforms log removals of 6, 4, and 3 were observed in algal, duckweed, and pistia ponds, respectively, in the final effluents, with die-off rates per pond of 2.7, 2.0, and 1.6. Sedimentation accounted for over 99% fecal coliform removal in most of the algal and pistia ponds. BOD removal was highest in the duckweed system, followed by pistia and algae at 95%, 93%, and 25%, respectively. COD removals were 65% and 59%, respectively, for duckweed and pistia, while COD increased in algal ponds by 56%. Nitrate removals were 72%, 70%, and 36%, respectively for duckweed, pistia, and algal ponds. Total phosphorus removals were 33% and 9% for pistia and duckweed systems, while an increase of 19% was observed in the algal treatment system. Ammonia removals were 95% in both pistia and duckweed and 93% in algal systems. Removals of total dissolved solids (TDS) were 70% for pistia, 15% for duckweed, and 9% for algae. Mosquito populations of 11,175/m(2), 3516/m(2), and 96/m(2) were counted in pistia, algal, and duckweed ponds, respectively. Low

  11. Event-based stormwater management pond runoff temperature model

    NASA Astrophysics Data System (ADS)

    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.

  12. Effects of urbanization on three ponds in Middleton, Wisconsin

    USGS Publications Warehouse

    House, Leo B.

    1984-01-01

    A digital hydrologic model was used to simulate the effects of future residential development on pond inflow volumes and resulting water levels of three ponds in Middleton, Wisconsin. The model computed the daily water budget and the resulting water level for each pond. The results of the model calibration are presented in the report, along with the existing watershed hydrologic conditions and runoff volumes for the 1982 study period. Data was collected during 1982 to claibrate the model; the data included pond stage, ground-water levels, precipitation and other meteorological characteristics. In addition, water-quality samples were collected at each pond to characterize the water quality. Simulation of pond levels with the 1982 rainfall and fully developed watersheds did not result in stages greater than those observed in 1982. Simulation of pond levels with rainfall having a 20-year recurrence interval (1978) and hypothetical, fully developed watersheds resulted in maximum pond stages above those observed in 1982. Peak stage of Tiedeman 's Pond would increase by 2.77 feet, Stricker 's Pond by 3.91 feet, and Esser 's Pond by 1.44 feet. Simulation of pond levels with an estimated 100-year rainfall and hyopthetical, fully developed watersheds would result in peak stage increases of 5.30, 5.32, and 1.97 feet above the peak 1982 observed stages for Tiedeman's, Stricker's, and Esser 's Ponds, respectively. (USGS)

  13. Geohydrology of the Flints Pond Aquifer, Hollis, New Hampshire

    USGS Publications Warehouse

    Ayotte, Joseph D.; Dorgan, Tracy H.

    1995-01-01

    Flints pond has been subjected to accelerated eutrophication as a result of watershed development (building of new homes and conversion of summer cottages into permanent homes) since the 1930's. Ground-water flow is the primary recharge and discharge mechanism for Flints Pond. The saturated thickness, transmissive properties, and altitude of the water table were determined by use of surface geophysics, test drilling, and aquifer-test data. Information on the geohydrology of the adjacent Flints Pond aquifer can be used in developing a water and nutrient budget for the pond-aquifer system. Ground-penetrating-radar surveys were done over more than 4 miles of the study area and on Flints Pond. Three distinct reflection signatures were commonly identifiable on the radar profiles: (1) thin, relatively flat-lying, continuous reflectors that represent fine-grained lacustrine sediment; (2) subparallel to hummocky and chaotic, coarse-grained reflectors that possibly represent coarse-grained ice-contact deposits or deltaic sediments in a lacustrine environment; and (3) sharply diffracted, fine-grained, chaotic reflectors that represent till and (or) till over bedrock. The saturated thickness of the aquifer exceeds 90 feet in the northern end of the study area and averages 30 to 50 feet in the southern and eastern parts. The saturated thickness of the western part is generally less than 10 feet. Test borings were completed at 19 sites and 13 wells (6 of which were nested pairs) were installed in various lithologic units. A water-table map, constructed from data collected in November 1994, represents average water-table conditions in the aquifer. Horizontal hydraulic conductivities calculated from single-well aquifer test data for stratified drift range from 2.8 to 226 feet per day. Hydraulic conductivities were quantitatively correlated with the reflector signatures produced with ground-penetrating radar so that transmissivities could be inferred for areas where well data were

  14. Effects of the herbicide metazachlor on macrophytes and ecosystem function in freshwater pond and stream mesocosms.

    PubMed

    Mohr, S; Berghahn, R; Feibicke, M; Meinecke, S; Ottenströer, T; Schmiedling, I; Schmiediche, R; Schmidt, R

    2007-05-01

    The chloroacetamide metazachlor is a commonly used pre-emergent herbicide to inhibit growth of plants especially in rape culture. It occurs in surface and ground water due to spray-drift or run-off in concentrations up to 100 microgL(-1). Direct and indirect effects of metazachlor on aquatic macrophytes were investigated at oligo- to mesotrophic nutrient levels employing eight stream and eight pond indoor mesocosms. Five systems of each type were dosed once with 5, 20, 80, 200 and 500 microgL(-1) metazachlor and three ponds and three streams served as controls. Pronounced direct negative effects on macrophyte biomass of Potamogeton natans, Myriophyllum verticillatum and filamentous green algae as well as associated changes in water chemistry were detected in the course of the summer 2003 in both pond and stream mesocosms. Filamentous green algae dominated by Cladophora glomerata were the most sensitive organisms in both pond and stream systems with EC(50) ranging from 3 (streams) to 9 (ponds) microgL(-1) metazachlor. In the contaminated pond mesocosms with high toxicant concentrations (200 and 500 microgL(-1)), a species shift from filamentous green algae to the yellow-green alga Vaucheria spec. was detected. The herbicide effects for the different macrophyte species were partly masked by interspecific competition. No recovery of macrophytes was observed at the highest metazachlor concentrations in both pond and stream mesocosms until the end of the study after 140 and 170 days. Based on the lowest EC(50) value of 4 microgL(-1) for total macrophyte biomass, it is argued that single exposure of aquatic macrophytes to metazachlor to nominal concentrations >5 microgL(-1) is likely to have pronounced long-term effects on aquatic biota and ecosystem function. PMID:17353057

  15. Salt Ponds, South San Francisco Bay

    NASA Technical Reports Server (NTRS)

    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

  16. ESTIMATING AMPHIBIAN OCCUPANCY RATES IN PONDS UNDER COMPLEX SURVEY DESIGNS

    EPA Science Inventory

    Monitoring the occurrence of specific amphibian species in ponds is one component of the US Geological Survey's Amphibian Monitoring and Research Initiative. Two collaborative studies were conducted in Olympic National Park and southeastern region of Oregon. The number of ponds...

  17. Natural or Simulated Ponds: An Environmental Baseline Study.

    ERIC Educational Resources Information Center

    Exline, Joseph D.

    1978-01-01

    Presents methods for analyzing soil and water samples in this classroom. Includes a classroom diagram, a listing of suggested materials, and the procedures for a classroom simulated pond. Relates classroom activities to work at a natural pond. (MA)

  18. 1. ENVIRONMENTAL VIEW OF SOUTHEAST PORTION OF LOWER POND AND ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. ENVIRONMENTAL VIEW OF SOUTHEAST PORTION OF LOWER POND AND SPILLWAY, LOOKING SOUTH - Whitman Estate, Lower Pond Spillway, Approx. .5 mile south of intersection of DE72 & Ebeneezer Church Road, Newark, New Castle County, DE

  19. 2. ENVIRONMENTAL VIEW OF SOUTHEAST PORTION OF LOWER POND AND ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. ENVIRONMENTAL VIEW OF SOUTHEAST PORTION OF LOWER POND AND SPILLWAY WITH FOREBAY IN FOREGROUND, LOOKING SOUTH - Whitman Estate, Lower Pond Spillway, Approx. .5 mile south of intersection of DE72 & Ebeneezer Church Road, Newark, New Castle County, DE

  20. Prototype computer-interactive goundwater monitoring methodology: an example for sedimentation ponds. Proj. report 1979-81

    SciTech Connect

    Everett, L.G.; Rasmussen, W.O.; Tempo, K.

    1983-04-01

    This report describes a prototype computer-interactive system that assists the development of a groundwater monitoring program for sedimentation ponds at coal strip mines. Even though the monitoring of sedimentation ponds is used as an example, the system consists of a set of instructions applicable to monitoring any specific groundwater pollution source. The instructions enable the user to select from a large amount of text information those portions appropriate to be written into his own file.

  1. Optimization and preconceptual design of a 5 MWe salt-gradient solar pond power plant at Great Salt Lake

    SciTech Connect

    Drost, M.K.; Brown, L.M.; Barnhart, J.S.; Cavola, R.G.; Hauser, S.G.; Johnson, B.M.

    1983-05-01

    The techniques used to optimize and design a solar salt-gradient pond (SSP) power plant for installation at the Great Salt Lake are described. The method and results of the site selection study are described as well as the characteristics of the selected site. The figure of merit used as well as the characteristics of the selected site. The figure of merit used in the optimization study, the general optimization approach, and the specific optimization method used for each subsystem are described. Results are then discussed of the optimization of the pond configuration, total system, and piping. Pond design and ground rule sensitivity studies are reported. (LEW)

  2. Effect of duckweed cover on greenhouse gas emissions and odour release from waste stabilisation ponds.

    PubMed

    van der Steen, N P; Nakiboneka, P; Mangalika, L; Ferrer, A V M; Gijzen, H J

    2003-01-01

    Treatment of wastewater in stabilisation pond systems prevents the negative environmental impact of uncontrolled disposal of sewage. However, even a natural treatment system may generate secondary negative environmental impacts in terms of energy consumption, emission of greenhouse gases and emission of odorous compounds. Whereas natural systems have an advantage over electro-mechanical systems in that they use less hardware and less energy, it is not yet known whether secondary environmental effects in the form of greenhouse gas emissions are lower for these systems. This research intends to be a first step in the direction of answering this question by assessing gas emissions from two types of natural systems, namely algae-based and duckweed-based stabilisation ponds. The H2S volatilisation from laboratory scale pond-reactors has been determined by drawing the air above the water surface continuously through a solution of 1 M NaOH for absorption of sulphide. The amount of H2S that volatilised from the algae pond-reactor, and was trapped in the NaOH trap, was found to be 2.5-86 mg/m2/day. The H2S volatilisation from the duckweed pond-reactor was found to be negligible, even though the sulphide concentration was 9.7 mg/l S(2-). The duckweed cover was a physical barrier for volatilisation, since bubbles were trapped in the cover. In addition the duckweed layer was found to be afavourable environment for both aerobic sulphide oxidisers (Beggiatoa gigantae) as well as for photosynthetic purple sulphur bacteria belonging to the genus Chromatium. These may also have contributed to the prevention of H2S volatilisation. Results on methane emissions were not conclusive so far, but the same mechanisms that prevent H2S volatilisation may also prevent methane volatilisation. Therefore it was concluded that duckweed covers on stabilisation ponds may reduce the emission of both odorous and greenhouse gases. PMID:14510229

  3. One year's experience with an operating saturated solar pond

    SciTech Connect

    Ochs, T.L.; Stojanoff, C.G.; Day, D.L.

    1980-01-01

    While the saturated non-convecting solar pond concept is not new, the borax pond at the Desert Research Institute (DRI) is the first application of the concept to an operating solar pond. As with any new application there have been experimentally identified problem areas. Four of these problems are discussed: 1) departure from saturation, 2) contamination, 3) bottom crystalization, and 4) covers.

  4. 33 CFR 117.598 - Eel Pond Channel.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Eel Pond Channel. 117.598 Section... DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Massachusetts § 117.598 Eel Pond Channel. The following requirements apply to the draw of Eel Pond (Water Street) drawbridge at mile 0.0 at...

  5. 33 CFR 117.598 - Eel Pond Channel.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Eel Pond Channel. 117.598 Section... DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Massachusetts § 117.598 Eel Pond Channel. The following requirements apply to the draw of Eel Pond (Water Street) drawbridge at mile 0.0 at...

  6. 33 CFR 117.598 - Eel Pond Channel.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Eel Pond Channel. 117.598 Section... DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Massachusetts § 117.598 Eel Pond Channel. The following requirements apply to the draw of Eel Pond (Water Street) drawbridge at mile 0.0 at...

  7. 33 CFR 117.598 - Eel Pond Channel.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Eel Pond Channel. 117.598 Section... DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Massachusetts § 117.598 Eel Pond Channel. The following requirements apply to the draw of Eel Pond (Water Street) drawbridge at mile 0.0 at...

  8. Degradation and bioavailability of sulfamethazine in pond water microcosms

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The antibiotic sulfamethazine can be transported from manured fields to farm ponds. We investigated the degradation and fate of sulfamethazine in small pond water microcosms. 14C-phenyl-sulfamethazine was added to the pond water column in a swine manure slurry or in water. Residual concentrations in...

  9. 33 CFR 117.598 - Eel Pond Channel.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Eel Pond Channel. 117.598 Section... DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Massachusetts § 117.598 Eel Pond Channel. The following requirements apply to the draw of Eel Pond (Water Street) drawbridge at mile 0.0 at...

  10. Trophic structure and avian communities across a salinity gradient in evaporation ponds of the San Francisco Bay estuary

    USGS Publications Warehouse

    Takekawa, J.Y.; Miles, A.K.; Schoellhamer, D.H.; Athearn, N.D.; Saiki, M.K.; Duffy, W.D.; Kleinschmidt, S.; Shellenbarger, G.G.; Jannusch, C.A.

    2006-01-01

    Commercial salt evaporation ponds comprise a large proportion of baylands adjacent to the San Francisco Bay, a highly urbanized estuary. In the past two centuries, more than 79% of the historic tidal wetlands in this estuary have been lost. Resource management agencies have acquired more than 10 000 ha of commercial salt ponds with plans to undertake one of the largest wetland restoration projects in North America. However, these plans have created debate about the ecological importance of salt ponds for migratory bird communities in western North America. Salt ponds are unique mesohaline (5–18 g l−1) to hyperhaline (> 40 g l−1) wetlands, but little is known of their ecological structure or value. Thus, we studied decommissioned salt ponds in the North Bay of the San Francisco Bay estuary from January 1999 through November 2001. We measured water quality parameters (salinity, DO, pH, temperature), nutrient concentrations, primary productivity, zooplankton, macroinvertebrates, fish, and birds across a range of salinities from 24 to 264 g l−1. Our studies documented how unique limnological characteristics of salt ponds were related to nutrient levels, primary productivity rates, invertebrate biomass and taxa richness, prey fish, and avian predator numbers. Salt ponds were shown to have unique trophic and physical attributes that supported large numbers of migratory birds. Therefore, managers should carefully weigh the benefits of increasing habitat for native tidal marsh species with the costs of losing these unique hypersaline systems.

  11. Trophic structure and avian communities across a salinity gradient in evaporation ponds of the San Francisco Bay estuary

    USGS Publications Warehouse

    Takekawa, J.Y.; Miles, A.K.; Schoellhamer, D.H.; Athearn, N.D.; Saiki, M.K.; Duffy, W.D.; Kleinschmidt, S.; Shellenbarger, G.G.; Jannusch, C.A.

    2006-01-01

    Commercial salt evaporation ponds comprise a large proportion of baylands adjacent to the San Francisco Bay, a highly urbanized estuary. In the past two centuries, more than 79% of the historic tidal wetlands in this estuary have been lost. Resource management agencies have acquired more than 10 000 ha of commercial salt ponds with plans to undertake one of the largest wetland restoration projects in North America. However, these plans have created debate about the ecological importance of salt ponds for migratory bird communities in western North America. Salt ponds are unique mesohaline (5-18 g l-1) to hyperhaline (> 40 g l-1) wetlands, but little is known of their ecological structure or value. Thus, we studied decommissioned salt ponds in the North Bay of the San Francisco Bay estuary from January 1999 through November 2001. We measured water quality parameters (salinity, DO, pH, temperature), nutrient concentrations, primary productivity, zooplankton, macroinvertebrates, fish, and birds across a range of salinities from 24 to 264 g l-1. Our studies documented how unique limnological characteristics of salt ponds were related to nutrient levels, primary productivity rates, invertebrate biomass and taxa richness, prey fish, and avian predator numbers. Salt ponds were shown to have unique trophic and physical attributes that supported large numbers of migratory birds. Therefore, managers should carefully weigh the benefits of increasing habitat for native tidal marsh species with the costs of losing these unique hypersaline systems. ?? Springer 2006.

  12. Real-Time In Situ Monitoring of Coupled Dynamics in Ponds

    NASA Astrophysics Data System (ADS)

    Branco, B.; Torgersen, T.; Bean, J.

    2002-05-01

    Shallow (< 2 m) ponds represent an important water quality component of the landscape. The bio- and chemodynamics are coupled to physical processes through diel cycles of thermal stratification and destratification as well as aperiodic precipitation events. Thus, a pond's coupled biological, physical and chemical dynamics and it's time scales of reaction and transport are of the order of minutes to days and requires hourly sampling at a minimum. The MyPond project has developed equipment and techniques to examine these dynamics in real-time through an Internet-based monitoring system that delivers streaming data for use in research and education. The MyPond system is currently being used to monitor the coupled dynamics of Mirror Lake (mean depth ~ 1.2 m) at the Storrs campus of the University of Connecticut. The diel stratification/destratification cycle is monitored using a thermistor array extending from the top of the water column to 10 cm into the sediments. An in-house designed pump profiler system allows high frequency (one sample every 5 minutes) automatic sampling of 6 to 8 sequential depths (one profile every ~ 30 minutes). A programmable microprocessor controls the timing and sequence of the sampling. Pond water is measured in a flow cell with a single YSI multi-parameter sonde for temperature, dissolved oxygen, pH, ORP, ammonium, turbidity, fluorescence and specific conductivity for each depth interval The datalogger is remotely queried via UCONN's data network. Graphical displays of the data are created automatically and served as images to the MyPond website. Pond water level and weather data are also provided in real-time. Thermal gradients as high as 0.14 deg C/cm are seen during daylight in summer months with daily `turnover' just before dawn. Strong diurnal patterns and top to bottom differences in e.g. photosynthetic oxygen production and carbon dioxide consumption as well as an ammonium flux from the sediment are clearly visible. It is commonly

  13. 120-D-1 (100-D) ponds training plan

    SciTech Connect

    G. B. Mitchem

    1997-12-31

    This is the Environmental Restoration Contractor Team training plan for the 100-D Ponds treatment, storage, and disposal unit. This plan is intended to meet the requirements of WAC 173-303-330 and the Hanford Dangerous Waste Permit. The WAC 173-303-330(1)(d)(ii, v, vi) requires that personnel be familiar, where applicable, with waste feed cut-off systems, proper responses to groundwater contamination incidents, shutdown of operations, response to fire or explosion, and other process operation activities.

  14. MONITORING OF A BEST MANAGEMENT PRACTICE POND

    EPA Science Inventory

    The USEPA's Urban Stormwater Management Branch has monitored stormwater drainage and best management practices (BMP) as part of its research program. One BMP being monitored, a wetland/retention pond, is in the Richmond Creek (RC) watershed in the New York City Department of Envi...

  15. Interconnected ponds operation for flood hazard distribution

    NASA Astrophysics Data System (ADS)

    Putra, S. S.; Ridwan, B. W.

    2016-05-01

    The climatic anomaly, which comes with extreme rainfall, will increase the flood hazard in an area within a short period of time. The river capacity in discharging the flood is not continuous along the river stretch and sensitive to the flood peak. This paper contains the alternatives on how to locate the flood retention pond that are physically feasible to reduce the flood peak. The flood ponds were designed based on flood curve number criteria (TR-55, USDA) with the aim of rapid flood peak capturing and gradual flood retuning back to the river. As a case study, the hydrologic condition of upper Ciliwung river basin with several presumed flood pond locations was conceptually designed. A fundamental tank model that reproducing the operation of interconnected ponds was elaborated to achieve the designed flood discharge that will flows to the downstream area. The flood hazard distribution status, as the model performance criteria, will be computed within Ciliwung river reach in Manggarai Sluice Gate spot. The predicted hazard reduction with the operation of the interconnected retention area result had been bench marked with the normal flow condition.

  16. Pacific white shrimp culture in inland ponds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Pacific white shrimp (Litopenaeus vannamei), a tropical species grown throughout Latin America and now introduced into Asia, adapts to and grows well in low-salinity water. Pond culture of L. vannamei has expanded to inland regions across the southern US where low-salinity ground water is availa...

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

    ERIC Educational Resources Information Center

    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.…

  18. Excavations in Hanford ponds, cribs, or ditches

    SciTech Connect

    Ryan, G.W., Westinghouse Hanford

    1996-07-30

    This document supports the development and presentation of the following accident scenario in the TWRS Final Safety Analysis Report: Unplanned Excavation/Drilling in Pond/Ditch/Crib. The calculations needed to quantify the risk associated with this accident scenario are included within.

  19. Ecology of Great Salt Pond, Block Island

    EPA Science Inventory

    Great Salt Pond is an island of estuarine water on Block Island, which sits in the middle of the Northwest Atlantic Continental Shelf. When the last continental glaciers retreated, they left a high spot on a terminal moraine. The rising sea from melting glaciers formed two island...

  20. Plankton Management for Channel Catfish Nursery Ponds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We conducted a series of studies examining the fertilization practices used for channel catfish nursery ponds. The best fertilization protocol would be one that uses low-cost fertilizers, quickly establishes a desirable phytoplankton bloom, and produces the greatest number of large zooplankton. In...

  1. Cibola High Levee Pond annual report 2004

    USGS Publications Warehouse

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

    2005-01-01

    Remaining work will be finished this coming summer and a final report describing CHLP and the ecology of these fish will be completed by the end of 2005. We offer our assistance to the Fish and Wildlife Service in the pond’s renovation and support for the creation of additional refuge ponds. Funding for this work ends September 2005.

  2. Source or Sink: Investigating the role of storm water retention ponds in the urban landscape (Invited)

    NASA Astrophysics Data System (ADS)

    Lev, S.; Casey, R.; Ownby, D.; Snodgrass, J.

    2009-12-01

    The impact of human activities on surface water, groundwater and soil is nowhere more apparent than in urban and suburban systems. Dramatic changes to watersheds in urbanizing areas have led to changes in hydrology and an associated increase in the flux of sediment and contaminants to surface and ground waters. In an effort to mediate these impacts, Best Management Practices (BMP) have been established in order to increase infiltration of runoff and trap sediment and particulates derived from impervious surfaces before they enter surface waters. Perhaps the most ubiquitous BMP are storm water retention ponds. While these structures are designed to reduce runoff and particulate loading to urban streams, their addition to the urban landscape has created a large number of new wetland habitats. In the Red Run watershed, just outside of Baltimore, Maryland, 186 discrete natural or man-made wetland areas have been identified. Of these 186 wetland areas, 165 were created to manage stormwater and most were specifically designed as stormwater management ponds (i.e., human-created basins or depressions that hold runoff for some period during the annual hydrological year). Despite their abundance in the landscape, very little is known about how these systems impact the flux of stormwater pollutants or affect the organisms using these ponds as habitat. Results from a series of related projects in the Red Run watershed are presented here in an effort to summarize the range of issues associated with stormwater management ponds. The Red Run watershed is situated inside the Urban-Rural Demarcation Line (URDL) around Baltimore City and has been identified as a smart growth corridor by Baltimore County. This region is one of two areas in Baltimore County where new development is focused. In a series of investigations of soils, surface and ground waters, and amphibian and earthworm use of 68 randomly selected stormwater retention ponds from the Red Run watershed, a range of

  3. Production and associated economics of fingerling to stocker to growout modular phases for farming channel catfish, Ictalurus punctatus, in commercial size ponds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A 2-year study was conducted to evaluate fingerling to stocker (phase 2) and stocker to growout (phase 3) of three phases of a modular production system for channel catfish in commercial-scale ponds. Fingerlings (mean = 14.3 kg/1000, 11.9 cm) were stocked into each of six earthen ponds (1.62 ha) at ...

  4. USING INTERNAL RADIO TRANSMITTERS TO DETERMINE THE BEHAVIORAL RESPONSE OF BULLFROGS, RANA CATESBEIANA, TO SEASONAL POND DRYING IN THE WILLAMETTE VALLEY, OREGON

    EPA Science Inventory

    We implanted radio tags in adult bullfrogs from three ponds located in a Willamette Valley game reserve to determine their behavior and habitat use as the ponds dried during late summer. We used radio telemetry and a Global Position System (GPS) to locate and record the position ...

  5. High Methylmercury in Arctic and Subarctic Ponds is Related to Nutrient Levels in the Warming Eastern Canadian Arctic.

    PubMed

    MacMillan, Gwyneth A; Girard, Catherine; Chételat, John; Laurion, Isabelle; Amyot, Marc

    2015-07-01

    Permafrost thaw ponds are ubiquitous in the eastern Canadian Arctic, yet little information exists on their potential as sources of methylmercury (MeHg) to freshwaters. They are microbially active and conducive to methylation of inorganic mercury, and are also affected by Arctic warming. This multiyear study investigated thaw ponds in a discontinuous permafrost region in the Subarctic taiga (Kuujjuarapik-Whapmagoostui, QC) and a continuous permafrost region in the Arctic tundra (Bylot Island, NU). MeHg concentrations in thaw ponds were well above levels measured in most freshwater ecosystems in the Canadian Arctic (>0.1 ng L(-1)). On Bylot, ice-wedge trough ponds showed significantly higher MeHg (0.3-2.2 ng L(-1)) than polygonal ponds (0.1-0.3 ng L(-1)) or lakes (<0.1 ng L(-1)). High MeHg was measured in the bottom waters of Subarctic thaw ponds near Kuujjuarapik (0.1-3.1 ng L(-1)). High water MeHg concentrations in thaw ponds were strongly correlated with variables associated with high inputs of organic matter (DOC, a320, Fe), nutrients (TP, TN), and microbial activity (dissolved CO2 and CH4). Thawing permafrost due to Arctic warming will continue to release nutrients and organic carbon into these systems and increase ponding in some regions, likely stimulating higher water concentrations of MeHg. Greater hydrological connectivity from permafrost thawing may potentially increase transport of MeHg from thaw ponds to neighboring aquatic ecosystems. PMID:26030209

  6. Modern to millennium-old greenhouse gases emitted from ponds and lakes of the Eastern Canadian Arctic (Bylot Island, Nunavut)

    NASA Astrophysics Data System (ADS)

    Bouchard, F.; Laurion, I.; Prėskienis, V.; Fortier, D.; Xu, X.; Whiticar, M. J.

    2015-12-01

    Ponds and lakes are widespread across the rapidly changing permafrost environments. Aquatic systems play an important role in global biogeochemical cycles, especially in greenhouse gas (GHG) exchanges between terrestrial systems and the atmosphere. The source, speciation and emission rate of carbon released from permafrost landscapes are strongly influenced by local conditions, hindering pan-Arctic generalizations. This study reports on GHG ages and emission rates from aquatic systems located on Bylot Island, in the continuous permafrost zone of the Eastern Canadian Arctic. Dissolved and ebullition gas samples were collected during the summer season from different types of water bodies located in a highly dynamic periglacial valley: polygonal ponds, collapsed ice-wedge trough ponds, and larger lakes. The results showed strikingly different ages and fluxes depending on aquatic system types. Polygonal ponds were net sinks of dissolved CO2, but variable sources of dissolved CH4. They presented the highest ebullition fluxes, 1 or 2 orders of magnitude higher than from other ponds and lakes. Trough ponds appeared as substantial GHG sources, especially when their edges were actively eroding. Both types of ponds produced modern to hundreds of years old (< 550 yr BP) GHG, even if trough ponds could contain much older carbon (> 2000 yr BP) derived from freshly eroded peat. Lakes had small dissolved and ebullition fluxes, however they released much older GHG, including millennium-old CH4 (up to 3500 yr BP) from lake central areas. Acetoclastic methanogenesis dominated at all study sites and there was minimal, if any, methane oxidation in gas emitted through ebullition. These findings provide new insights on GHG emissions by permafrost aquatic systems and their potential positive feedback effect on climate.

  7. Effects of detention on water quality of two stormwater detention ponds receiving highway surface runoff in Jacksonville, Florida

    USGS Publications Warehouse

    Hampson, P.S.

    1986-01-01

    Water and sediment samples were analyzed for major chemical constituents, nutrients, and heavy metals following ten storm events at two stormwater detention ponds that receive highway surface runoff in the Jacksonville, Florida, metropolitan area. The purpose of the sampling program was to detect changes in constituent concentration with time of detention within the pond system. Statistical inference of a relation with total rainfall was found in the initial concentrations of 11 constituents and with antecedent dry period for the initial concentrations of 3 constituents. Based on graphical examination and factor analysis , constituent behavior with time could be grouped into five relatively independent processes for one of the ponds. The processes were (1) interaction with shallow groundwater systems, (2) solubilization of bottom materials, (3) nutrient uptake, (4) seasonal changes in precipitation, and (5) sedimentation. Most of the observed water-quality changes in the ponds were virtually complete within 3 days following the storm event. (Author 's abstract)

  8. Large Lava Pond Complex on the Juan de Fuca Ridge: an Effusive, Energetic Eruption that Drained Away

    NASA Astrophysics Data System (ADS)

    Paduan, J. B.; Clague, D. A.; Davis, A. S.; Chadwick, W.; Cousens, B. L.; Embley, R. W.

    2005-12-01

    We explored an unusually large, deep, drained lava lake complex on the south rift of Axial Seamount on the Juan de Fuca Ridge during three dives with the ROV Tiburon in August 2005. The complex of five large ponds, first identified from EM300 multibeam bathymetry, is 5 km long and more than 1 km wide. The ponds are separated from one another by narrow levees that rise about 90 meters above the pond floors. The levees are all about the same depth, which suggests that the ponds formed at the same time. The volume of the lake, prior to draining, was 0.2-0.4 km3, making it the largest lava lake known along the ridge system. The outer slopes of the pond levees are constructed of elongate pillows that flowed down the steep slopes. The rims are narrow, level plateaus of lobate flows with many collapses. The inner walls are vertical cliffs, overhanging in places, with horizontal shelves from the top of the levees down to the floors of the ponds. Left like bathtub rings, these shelves mark former surfaces of the lava pond as it drained away while the lava was still molten. In many places, this veneer has collapsed to reveal truncated lobate flows and pillows. The floor of one small pond was entirely talus blocks. However, the floors of the other, larger ponds had little talus and, instead, were vast expanses of thin broken crusts, lobate flows, and very fluid, chaotic, folded and jumbled sheet flows. The lavas from each pond have abundant large feldspar and rarer olivine crystals, suggesting that all were from the same eruption. This eruption apparently began with sheet flows whose advance was limited by topography. It then ponded and built up the levees that were left when the lava drained away. On the floor of one pond we found a deposit several meters tall that was delicate and difficult to sample, and turned out to be agglutinated spatter. Limu o Pele (lava bubble wall fragments) was abundant in all the sediment samples in and around the ponds. The spatter and limu

  9. Fish Scale Evidence for Rapid Post Glacial Colonization of an Atlantic Coastal Pond

    NASA Technical Reports Server (NTRS)

    Daniels, R. A.; Peteet, Dorothy

    1996-01-01

    Fish scales from the sediment of Allamuchy Pond, New Jersey, USA, indicate that fishes were present in the pond within 400 years of the time of the first deposition of organic material, at approximately 12,600 yrs BP. The earliest of the scales, from a white sucker, Catostomus commersoni, appears in sediment dated 12,260 +/- 220 yrs BP. Presence of scales in sediment deposited before I 0,000 yrs BP indicates that Atlantic salmon, Salmo salar, sunfish, Lepomis sp., and yellow perch, Perca flavescens, also were early inhabitants of the pond. The timing of the arrival of each of these fishes suggests that they migrated out from Atlantic coastal refugia. A minnow scale, referred to Phoxininae, was also retrieved; it could not be matched to any cyprinid currently found in northeastern North America. The species present historically in this pond are from five families found currently in ponds throughout the Northeast and sugoest that the lentic palaeo-enviromnent was similar to present mid-elevation or high-latitude lentic systems.

  10. The design, construction, and initial operation of a closed-cycle, salt-gradient solar pond

    SciTech Connect

    Alagao, F.B.; Akbarzadeh, A.; Johnson, P.W. )

    1994-10-01

    In operation of a closed-cycle salt-gradient solar pond (CCSGSP) system, fresh or low salinity water is supplied at the surface of the solar pond (SP) as make-up for evaporation losses as well as for surface washing. In the present investigation the surface water is flushed to an evaporation pond (EP) and concentrated for reinjection at the bottom of the SP. A 20 m[sup 2] SP incorporating an EP for concentrating brine, has been established. Theoretical modelling of the CCSGSP is presented. Results from the initial operation of the SP show that wind action and convective mixing caused some erosion of the gradient layer thereby increasing the surface layer thickness. Salt flux to the surface was found to be approximately 19 kg/m[sup 2] per year. Sodium hypochlorite solution proved successful as shock treatment during severe algal bloom. The result of acidification w as less promising in maintaining pond clarity. Occasional addition of alum helped in settling some of the suspended particulates in the pond.

  11. Photodemethylation of Methylmercury in Eastern Canadian Arctic Thaw Pond and Lake Ecosystems.

    PubMed

    Girard, Catherine; Leclerc, Maxime; Amyot, Marc

    2016-04-01

    Permafrost thaw ponds of the warming Eastern Canadian Arctic are major landscape constituents and often display high levels of methylmercury (MeHg). We examined photodegradation potentials in high-dissolved organic matter (DOC) thaw ponds on Bylot Island (BYL) and a low-DOC oligotrophic lake on Cornwallis Island (Char Lake). In BYL, the ambient MeHg photodemethylation (PD) rate over 48 h of solar exposure was 6.1 × 10(-3) m(2) E(-1), and the rate in MeHg amended samples was 9.3 × 10(-3) m(2) E(-1). In contrast, in low-DOC Char Lake, PD was only observed in the first 12 h, which suggests that PD may not be an important loss process in polar desert lakes. Thioglycolic acid addition slowed PD, while glutathione and chlorides did not impact northern PD rates. During an ecosystem-wide experiment conducted in a covered BYL pond, there was neither net MeHg increase in the dark nor loss attributable to PD following re-exposure to sunlight. We propose that high-DOC Arctic thaw ponds are more prone to MeHg PD than nearby oligotrophic lakes, likely through photoproduction of reactive species rather than via thiol complexation. However, at the ecosystem level, these ponds, which are widespread through the Arctic, remain likely sources of MeHg for neighboring systems. PMID:26938195

  12. Combining mariculture and seawater-based solar ponds

    SciTech Connect

    Lowrey, P.; Ford, R.; Collando, F.; Morgan, J.; Frusti, E. . Dept. of Mechanical Engineering)

    1990-05-01

    Solar ponds have been thoroughly studied as a means to produce electricity or heat, but there may be comparable potential to use solar ponds to produce optimized environments for the cultivation of some aquaculture crops. For this, conventional brine-based solar ponds could be used. This strategy would probably be most suitable at desert sites where concentrated brine was abundant, pond liners might not be needed, and the crop produced could be shipped to market. Generally, a heat exchanger would be required to transfer heat from the solar pond into the culture ponds. Culture ponds could therefore use either fresh or marine water. In contrast, this paper explores seawater-based solar ponds. These are solar ponds which use seawater in the bottom storage zone and fresh water in the upper convective zone. Because the required temperature elevations for mariculture are only about 10{degrees}C, seawater-based solar ponds are conceivable. Seawater-based ponds should be very inexpensive because, by the shore, salt costs would be negligible and a liner might be unnecessary.

  13. Effect of soil conditions on solar pond performance

    SciTech Connect

    Leboeuf, C.M.; Johnson, D.H.

    1984-01-01

    A recent effort to design a one-acre solar pond at the US Air Force Academy brought up several research issues pertaining to solar pond performance prediction. This report addresses those issues. Interactions of the pond with the soil below it have historically been estimated using very simplistic techniques that tend to ignore soil composition, moisture content, and the coupled heat and moisture transport phenomena. This study examines the models of soil thermal conductivity and heat and mass transport in soils under imposed temperature gradients to assess the potential applicability of these models to solar pond modeling. In addition, a computer simulation code is developed that incorporates the soil thermal conductivity model. Using the code, a parametric analysis was performed illustrating the impact of this property on pond behavior and the importance of experimental model verification for the range of soil temperatures experienced in solar ponds. Implications of the combined heat and moisture movement theory on solar pond performance are presented.

  14. Mercury Cycling in Salt Marsh Pond Ecosystems: Cape Cod, MA

    NASA Astrophysics Data System (ADS)

    Ganguli, P. M.; Gonneea, M. E.; Lamborg, C. H.; Kroeger, K. D.; Swarr, G.; Vadman, K. J.; Baldwin, S.; Brooks, T. W.; Green, A.

    2014-12-01

    We are measuring total mercury (HgT) and monomethylmercury (CH3Hg+ or MMHg) in pore water, surface water, and sediment cores from two salt marsh pond systems on the south shore of Cape Cod, MA to characterize the distribution of mercury species and to identify features that influence mercury speciation and transport. Sage Lot Pond is relatively undisturbed and has low nitrogen loading (12 kg ha-1 y-1). It is part of the Waquoit Bay National Estuarine Reserve and is surrounded by undeveloped wooded uplands. In contrast, Great Pond is highly impacted. Nitrogen loading to the site is elevated (600 kg ha-1 y-1) and the marsh is adjacent to a large residential area. In both systems, a 1 to 2 m organic-rich peat layer overlies the permeable sand aquifer. Groundwater in this region is typically oxic, where pore water within salt marsh peat is suboxic to anoxic. We hypothesize that redox gradients at the transition from the root zone to peat and at the peat-sand interface may provide habitat for MMHg-producing anaerobic bacteria. Preliminary results from a 2-m nearshore depth profile at Sage Lot Pond indicate HgT in groundwater within the sand aquifer occurred primarily in the > 0.2 μm fraction, with unfiltered concentrations exceeding 100 pM. Filtered (< 0.2 μm) HgT in groundwater was substantially lower (~ 5 pM). In contrast, HgT concentrations in filtered and unfiltered pore water within the peat layer were similar and ranged from about 2 to 3 pM. Complexation between mercury and dissolved organic carbon may account for the elevated fraction of filtered HgT in peat pore water. Although MMHg in both groundwater and pore water remained around 1 pM throughout our depth profile, we observed an increase in sediment MMHg (0.3 to 1.6 μg/kg) at the peat-sand interface. MMHg comprised ~50% of the HgT concentration in pore water suggesting mercury in the salt marsh peat is biologically available.

  15. Geochemistry and toxicity of sediment porewater in a salt-impacted urban stormwater detention pond.

    PubMed

    Mayer, T; Rochfort, Q; Borgmann, U; Snodgrass, W

    2008-11-01

    A comprehensive study was carried out to investigate the impacts of road salts on the benthic compartment of a small urban detention facility, Rouge River Pond. Although the pond is an engineered water body, it is representative of many small urban lakes, ponds and wetlands, which receive road runoff and are probable high impact areas. Specific objectives of the study were to document the porewater chemistry of an aquatic system affected by elevated salt concentrations and to carry out a toxicological assessment of sediment porewater to determine what factors may cause porewater toxicity. The results indicate that the sediment porewater may itself attain high salt concentrations. The computations show that increased chloride levels have important implications on the Cd complexation, augmenting its concentration in porewater. The toxicity tests suggest that the toxicity in porewater is caused by metals or other toxic chemicals, rather than high levels of chloride. PMID:18242807

  16. Suppression of ice fog from the Fort Wainwright, Alaska, cooling pond. Special report

    SciTech Connect

    Walker, K.E.; Brunner, W.

    1982-10-01

    Ice fog near the Ft. Wainwright cooling pond creates a visibility hazard. Observations show a substantial reduction in visibility along both private and public roadways in the path of the cooling pond's ice fog plume. This reduction in visibility increases as the ambient air temperature decreases. Visibility was less than 215 m (700 ft) on the Richardson Highway on the average of 8 days for each of the 3 data years. Data collected during the winters of 1979-80, 1980-81 and 1981-82 statistically show that use of a monomolecular film evaporation suppressant, hexadecanol (C16H33OH), on the pond to reduce ice fog is ineffective. There is an immediate need for a driver warning system when visibility is affected by the ice fog.

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

    DOE PAGESBeta

    Crowe, Braden; Attalah, Said; Agrawal, Shweta; Waller, Peter; Ryan, Randy; Van Wagenen, Jon; Chavis, Aaron; Kyndt, John; Kacira, Murat; Ogden, Kim L.; et al

    2012-01-01

    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 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 superiormore » 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.« less

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

    SciTech Connect

    Crowe, Braden; Attalah, Said; Agrawal, Shweta; Waller, Peter; Ryan, Randy; Van Wagenen, Jon; Chavis, Aaron; Kyndt, John; Kacira, Murat; Ogden, Kim L.; Huesemann, Michael

    2012-01-01

    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 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.

  19. Denitrification and anammox in tropical aquaculture settlement ponds: an isotope tracer approach for evaluating N2 production.

    PubMed

    Castine, Sarah A; Erler, Dirk V; Trott, Lindsay A; Paul, Nicholas A; de Nys, Rocky; Eyre, Bradley D

    2012-01-01

    Settlement ponds are used to treat aquaculture discharge water by removing nutrients through physical (settling) and biological (microbial transformation) processes. Nutrient removal through settling has been quantified, however, the occurrence of, and potential for microbial nitrogen (N) removal is largely unknown in these systems. Therefore, isotope tracer techniques were used to measure potential rates of denitrification and anaerobic ammonium oxidation (anammox) in the sediment of settlement ponds in tropical aquaculture systems. Dinitrogen gas (N(2)) was produced in all ponds, although potential rates were low (0-7.07 nmol N cm(-3) h(-1)) relative to other aquatic systems. Denitrification was the main driver of N(2) production, with anammox only detected in two of the four ponds. No correlations were detected between the measured sediment variables (total organic carbon, total nitrogen, iron, manganese, sulphur and phosphorous) and denitrification or anammox. Furthermore, denitrification was not carbon limited as the addition of particulate organic matter (paired t-Test; P = 0.350, n = 3) or methanol (paired t-Test; P = 0.744, n = 3) did not stimulate production of N(2). A simple mass balance model showed that only 2.5% of added fixed N was removed in the studied settlement ponds through the denitrification and anammox processes. It is recommended that settlement ponds be used in conjunction with additional technologies (i.e. constructed wetlands or biological reactors) to enhance N(2) production and N removal from aquaculture wastewater. PMID:22962581

  20. Denitrification and Anammox in Tropical Aquaculture Settlement Ponds: An Isotope Tracer Approach for Evaluating N2 Production

    PubMed Central

    Castine, Sarah A.; Erler, Dirk V.; Trott, Lindsay A.; Paul, Nicholas A.; de Nys, Rocky; Eyre, Bradley D.

    2012-01-01

    Settlement ponds are used to treat aquaculture discharge water by removing nutrients through physical (settling) and biological (microbial transformation) processes. Nutrient removal through settling has been quantified, however, the occurrence of, and potential for microbial nitrogen (N) removal is largely unknown in these systems. Therefore, isotope tracer techniques were used to measure potential rates of denitrification and anaerobic ammonium oxidation (anammox) in the sediment of settlement ponds in tropical aquaculture systems. Dinitrogen gas (N2) was produced in all ponds, although potential rates were low (0–7.07 nmol N cm−3 h−1) relative to other aquatic systems. Denitrification was the main driver of N2 production, with anammox only detected in two of the four ponds. No correlations were detected between the measured sediment variables (total organic carbon, total nitrogen, iron, manganese, sulphur and phosphorous) and denitrification or anammox. Furthermore, denitrification was not carbon limited as the addition of particulate organic matter (paired t-Test; P = 0.350, n = 3) or methanol (paired t-Test; P = 0.744, n = 3) did not stimulate production of N2. A simple mass balance model showed that only 2.5% of added fixed N was removed in the studied settlement ponds through the denitrification and anammox processes. It is recommended that settlement ponds be used in conjunction with additional technologies (i.e. constructed wetlands or biological reactors) to enhance N2 production and N removal from aquaculture wastewater. PMID:22962581

  1. Aspects of flow attenuation performance of retention ponds

    NASA Astrophysics Data System (ADS)

    Wallis, S. G.; Morgan, C. T.; Heal, K.

    2003-04-01

    The work reported here is part of a wider modelling study into the performance of sustainable urban drainage systems (SUDS) in Scotland. Developments that increase the urbanisation of catchments are now required by the Scottish Environment Protection Agency to include SUDS to protect receiving watercourses from flooding and water quality deterioration. Here we report specifically on some initial simulations of storm water retention ponds. These are normally wet storage facilities that provide both flow attenuation and water quality treatment (from settlement of suspended solids and biological treatment of some pollutants). Here we focus on the flow attenuation characteristics. A sensitivity analysis was performed on a model of a cylindrical pond with outflow through a V-notch weir. The aim of the simulations was to help us to learn about the flow attenuation characteristics of retention ponds, so that later work could be properly focused on the key issues. In addition the flow simulation model underpins later models of water quality and sedimentation, so it was important to ensure that its simulations were realistic. The inflows were constructed using an isosceles triangular inflow hydrograph with a peak flow of 50 l/s, a storm duration of 3.2 hours and a total inflow volume of 288 l. Values of four pond parameters were varied to test model sensitivity: radius, weir angle, weir crest elevation and initial water level. Sensitivity was investigated by observing the changes in several flow attenuation performance indicators. These were total outflow volume, peak outflow and the following three time delays: peak time delay (lag between peaks of outflow and inflow hydrographs), centroid time delay (lag between centroids of outflow and inflow hydrographs) and initial time delay (lag between the initial rise of the outflow and inflow hydrographs). Simulations were carried out using a simple Euler discretisation of the storage routing equation. A time step of 1.5 minutes

  2. Examining the area effect for parasite communities of bluegill x green sunfish hybrids in five constructed ponds in Kansas.

    PubMed

    Zelmer, Derek A; Campbell, Johnathon K

    2011-04-01

    The parasite communities of bluegill x green sunfish hybrids were examined from 5 constructed ponds in Kansas in an attempt to evaluate the separate effects of habitat area and habitat heterogeneity on parasite community structure. Characterization of fish community structure and collection of hybrid fishes was conducted using an electrofishing boat. Benthic invertebrates were sampled, and substrate types examined at 30 evenly spaced points in each pond. Nonmetric multidimensional scaling of the parasite infracommunities, in concert with an analysis of similarities, indicated significant clustering of infracommunities by locality. The number and diversity of habitat types, and the richness and diversity of both fishes and benthic invertebrates, were positively correlated with the first axis of the infracommunity ordination. Pond surface area, parasite richness, and stocking pressure were negatively correlated with the first axis of the infracommunity ordination, suggesting that pond area, stocking pressure, or both was a stronger determinant of parasite community structure in these systems than habitat and host heterogeneity. PMID:21506793

  3. Unintended consequences of management actions in salt pond restoration: cascading effects in trophic interactions.

    PubMed

    Takekawa, John Y; Ackerman, Joshua T; Brand, L Arriana; Graham, Tanya R; Eagles-Smith, Collin A; Herzog, Mark P; Topping, Brent R; Shellenbarger, Gregory G; Kuwabara, James S; Mruz, Eric; Piotter, Sara L; Athearn, Nicole D

    2015-01-01

    Salt evaporation ponds have played an important role as habitat for migratory waterbirds across the world, however, efforts to restore and manage these habitats to maximize their conservation value has proven to be challenging. For example, salinity reduction has been a goal for restoring and managing former salt evaporation ponds to support waterbirds in the South Bay Salt Pond Restoration Project in San Francisco Bay, California, USA. Here, we describe a case study of unexpected consequences of a low-dissolved oxygen (DO) event on trophic interactions in a salt pond system following management actions to reduce salinity concentrations. We document the ramifications of an anoxic event in water quality including salinity, DO, and temperature, and in the response of the biota including prey fish biomass, numerical response by California Gulls (Larus californicus), and chick survival of Forster's Tern (Sterna forsteri). Management actions intended to protect receiving waters resulted in decreased DO concentrations that collapsed to zero for ≥ 4 consecutive days, resulting in an extensive fish kill. DO depletion likely resulted from an algal bloom that arose following transition of the pond system from high to low salinity as respiration and decomposition outpaced photosynthetic production. We measured a ≥ 6-fold increase in biomass of fish dropped on the levee by foraging avian predators compared with weeks prior to and following the low-DO event. California Gulls rapidly responded to the availability of aerobically-stressed and vulnerable fish and increased in abundance by two orders of magnitude. Mark-recapture analysis of 254 Forster's Tern chicks indicated that their survival declined substantially following the increase in gull abundance. Thus, management actions to reduce salinity concentrations resulted in cascading effects in trophic interactions that serves as a cautionary tale illustrating the importance of understanding the interaction of water quality

  4. Unintended consequences of management actions in salt pond restoration: cascading effects in trophic interactions

    USGS Publications Warehouse

    Takekawa, John Y.; Ackerman, Joshua T.; Brand, Arriana; Graham, Tanya R.; Eagles-Smith, Collin A.; Herzog, Mark; Topping, Brent R.; Shellenbarger, Gregory; Kuwabara, James S.; Mruz, Eric; Piotter, Sara L.; Athearn, Nicole D.

    2015-01-01

    Salt evaporation ponds have played an important role as habitat for migratory waterbirds across the world, however, efforts to restore and manage these habitats to maximize their conservation value has proven to be challenging. For example, salinity reduction has been a goal for restoring and managing former salt evaporation ponds to support waterbirds in the South Bay Salt Pond Restoration Project in San Francisco Bay, California, USA. Here, we describe a case study of unexpected consequences of a low-dissolved oxygen (DO) event on trophic interactions in a salt pond system following management actions to reduce salinity concentrations. We document the ramifications of an anoxic event in water quality including salinity, DO, and temperature, and in the response of the biota including prey fish biomass, numerical response by California Gulls (Larus californicus), and chick survival of Forster's Tern (Sterna forsteri). Management actions intended to protect receiving waters resulted in decreased DO concentrations that collapsed to zero for ≥ 4 consecutive days, resulting in an extensive fish kill. DO depletion likely resulted from an algal bloom that arose following transition of the pond system from high to low salinity as respiration and decomposition outpaced photosynthetic production. We measured a ≥ 6-fold increase in biomass of fish dropped on the levee by foraging avian predators compared with weeks prior to and following the low-DO event. California Gulls rapidly responded to the availability of aerobically-stressed and vulnerable fish and increased in abundance by two orders of magnitude. Mark-recapture analysis of 254 Forster's Tern chicks indicated that their survival declined substantially following the increase in gull abundance. Thus, management actions to reduce salinity concentrations resulted in cascading effects in trophic interactions that serves as a cautionary tale illustrating the importance of understanding the interaction of water quality

  5. Suitability of constructed wetlands and waste stabilisation ponds in wastewater treatment: nitrogen transformation and removal

    NASA Astrophysics Data System (ADS)

    Senzia, M. A.; Mashauri, D. A.; Mayo, A. W.

    It is estimated that 90% of sewage in cities in developing countries are today discharged untreated into water bodies. In Tanzania, pollution of rivers such as Karanga, Njoro and Rao in Moshi; Mirongo in Mwanza and Themi in Arusha is the cause of frequent disease outbreaks in communities downstreams. Solutions to effluent crisis can be found by its proper treatment and disposal. The principal objective of wastewater treatment is to allow effluents to be disposed without danger to human health or unacceptable damage to the ecology of receiving water bodies. Field investigations were made on pilot scale horizontal subsurface flow constructed wetlands (CW) units located downstream of waste stabilisation ponds (WSP). Six units filled with gravel of 6-25 mm diameters in equal proportion, which gave an initial hydraulic conductivity of 86 m/d were used. While four units covering surface area of 40.7 m 2 each, were located downstream of primary facultative pond, the other two units with surface area 15.9 m 2 each were located downstream of maturation pond. An attempt was made to compare the output of mathematical models for Phragmites and Typha macrophytes located downstream of primary facultative pond. Based on total inflow nitrogen of 1.457 gN/m 2 d, while Phragmites has shown a removal of 54%, Typha had a removal of 44.2%. Furthermore, while the system downstream of primary facultative pond has accretion as a major pathway, accounting for 19.1% of inflow nitrogen, the system downstream of maturation pond has denitrification as its major removal mechanism accounting for 20.5%. In this paper, a comparison of land required by CW and WSP based on the amount of water to be treated is made.

  6. Unintended Consequences of Management Actions in Salt Pond Restoration: Cascading Effects in Trophic Interactions

    PubMed Central

    Takekawa, John Y.; Ackerman, Joshua T.; Brand, L. Arriana; Graham, Tanya R.; Eagles-Smith, Collin A.; Herzog, Mark P.; Topping, Brent R.; Shellenbarger, Gregory G.; Kuwabara, James S.; Mruz, Eric; Piotter, Sara L.; Athearn, Nicole D.

    2015-01-01

    Salt evaporation ponds have played an important role as habitat for migratory waterbirds across the world, however, efforts to restore and manage these habitats to maximize their conservation value has proven to be challenging. For example, salinity reduction has been a goal for restoring and managing former salt evaporation ponds to support waterbirds in the South Bay Salt Pond Restoration Project in San Francisco Bay, California, USA. Here, we describe a case study of unexpected consequences of a low-dissolved oxygen (DO) event on trophic interactions in a salt pond system following management actions to reduce salinity concentrations. We document the ramifications of an anoxic event in water quality including salinity, DO, and temperature, and in the response of the biota including prey fish biomass, numerical response by California Gulls (Larus californicus), and chick survival of Forster's Tern (Sterna forsteri). Management actions intended to protect receiving waters resulted in decreased DO concentrations that collapsed to zero for ≥ 4 consecutive days, resulting in an extensive fish kill. DO depletion likely resulted from an algal bloom that arose following transition of the pond system from high to low salinity as respiration and decomposition outpaced photosynthetic production. We measured a ≥ 6-fold increase in biomass of fish dropped on the levee by foraging avian predators compared with weeks prior to and following the low-DO event. California Gulls rapidly responded to the availability of aerobically-stressed and vulnerable fish and increased in abundance by two orders of magnitude. Mark-recapture analysis of 254 Forster's Tern chicks indicated that their survival declined substantially following the increase in gull abundance. Thus, management actions to reduce salinity concentrations resulted in cascading effects in trophic interactions that serves as a cautionary tale illustrating the importance of understanding the interaction of water quality

  7. Avian response to early tidal salt marsh restoration at former commercial salt evaporation ponds in San Francisco Bay, California, USA

    USGS Publications Warehouse

    Athearn, Nicole D.; Takekawa, John Y.; Shinn, Joel

    2009-01-01

    Restoration of former commercial salt evaporation ponds in the San Francisco Bay estuary is intended to reverse a severe decline (>79%) in tidal salt marshes. San Francisco Bay is a critical migratory stopover site and wintering area for shorebirds and waterfowl, and salt ponds are important high tide roosting and foraging areas. Conservation of past bird abundance is a stated goal of area restoration projects, and early adaptive management will be critical for achieving this objective. However, initial avian response at sites restored to tidal flow may not be indicative of long-term results. For example, winter shorebirds at a 529 ha pond breached in 2002 showed a marked increase in shorebird abundance following breaching. Shorebirds comprised 1% of area totals during 1999-2002 and increased to 46% during 2003-2008. These changes accompanied increased tidal range and sedimentation, but minimal vegetation establishment. Conversely, a fully vegetated, restored 216 ha pond in the same system consistently supported less than 2% of all waterbirds in the region. Early restoration may temporarily increase habitat, but managed ponds will be needed for long-term waterbird abundance within a restored pond-marsh system.

  8. Beaver ponds increase methylmercury concentrations in Canadian shield streams along vegetation and pond-age gradients.

    PubMed

    Roy, Virginie; Amyot, Marc; Carignan, Richard

    2009-08-01

    Beaver impoundments flood forested areas and may be important production sites for methylmercury (MeHg) because of the resulting enhanced microbial activity and oxygen depletion. The influence of 17 beaver impoundments on streamwater chemistry (total mercury (THg), MeHg, nutrients, cations, and anions)] was investigated by sampling sites located along vegetation and pond-age gradients in southwestern Quebec (Canada). Recently inundated beaver ponds (< 10 years old) and those located in coniferous watersheds had the highest MeHg concentrations (range, 0.10-4.53 ng L(-1)) and greatest methylation efficiencies (% THg as MeHg; range, 10-74%). High heterotrophic activity likely occurred in the beaver ponds as suggested by depletions of dissolved oxygen, sulfate and nitrite-nitrate concentrations, and increases in nutrients (e.g., dissolved organic carbon, total phosphorus, and total nitrogen) in outlets compared to inlets. Acidic waters at coniferous sites may have stimulated more MeHg production than in mixed woodland regions. Lower methylation efficiencies in older ponds (> 20 years old) may be due to the degradation of less labile organic matter as ponds age. Beavers actively alter watersheds by building impoundments, and our findings indicate that this landscape disturbance may be a significant source of MeHg to downstream water bodies. PMID:19731651

  9. New approaches for Artemia pond culture.

    PubMed

    Van Hoa, Nguyen; Le Tran, Huu; Hong Van, Nguyen Thi; Sorgeloos, P; Van Stappen, G

    2013-01-01

    A project for intensive culture of Artemia in Vinhchau solar saltwork was funded by Soctrang Authority. The aim of this project is to increase the average cyst yield of 50kg.ha-1.crop, and to build up a stable culture technique with a better yield for local farmers. Multiple laboratory experiments were set up with inert food including fermented rice bran, tiger shrimp feed (PL15), as well as their combination with live algae (Chaetoceros). Results showed that, under laboratory conditions, fermented rice bran and tiger shrimp feed can be used as supplemental food sources. The shrimp feed alone or in combination with algae always gave better cyst production compared to the others, but should not account for more than 50% of the diet. In the field trials, aeration of Artemia ponds also increased cyst yields (from 195.8+/-44.2 to 207+/-46.1kg.ha-1.crop with 6 and 12 aeration a day, respectively) compared to ponds with no aeration (88.2+/-27.5kg.ha-1.crop), however the returns on investment (ROI=2.73-2.71 with aera tion vs. 2.24 without) are not significantly different. Utilization of fermented rice bran (20kg.ha-1.day) and shrimp feed (6kg.ha-1.day) as a supplementary feed during pond production in combination with greenwater supplies (10% of pond volume daily) resulted in higher yields (96.0+/-15.9 and 157.2+/-15.0kg.ha-1.crop, respectively) than traditional culture; Shrimp feed as a supplemental feed supported the cyst yield but their negative effect was at a high cost vs. traditional culture and use of fermented rice bran. Based on the cyst yield and ROI, fermented rice bran should be a promising item for poor farmers. PMID:25141701

  10. Par Pond refill water quality sampling

    SciTech Connect

    Koch, J.W. II; Martin, F.D.; Westbury, H.M.

    1996-08-01

    This study was designed to document anoxia and its cause in the event that the anoxia caused a fish kill. However, no fish kill was observed during this study, and dissolved oxygen and nutrient concentrations generally remained within the range expected for southeastern reservoirs. Par Pond water quality monitoring will continue during the second summer after refill as the aquatic macrophytes become reestablished and nutrients in the sediments are released to the water column.

  11. Water quality and restoration in a coastal subdivision stormwater pond.

    PubMed

    Serrano, Lorimar; DeLorenzo, Marie E

    2008-07-01

    Stormwater ponds are commonly used in residential and commercial areas to control flooding. The accumulation of urban contaminants in stormwater ponds can lead to a number of water quality problems including high nutrient, chemical contaminant, and bacterial levels. This study examined the interaction between land use and coastal pond water quality in a South Carolina residential subdivision pond. Eutrophic levels of chlorophyll and phosphorus were present in all seasons. Harmful cyanobacterial blooms were prevalent during the summer months. Microcystin toxin and fecal coliform bacteria levels were measured that exceeded health and safety standards. Low concentrations of herbicides (atrazine and 2,4-D) were also detected during summer months. Drainage from the stormwater pond may transport contaminants into the adjacent tidal creek and estuary. A survey of residents within the pond's watershed indicated poor pet waste management and frequent use of fertilizers and pesticides as possible contamination sources. Educational and outreach activities were provided to community members to create an awareness of the water quality conditions in the pond. Pond management strategies were then recommended, and selected mitigation actions were implemented. Water quality problems identified in this study have been observed in other coastal stormwater ponds of varying size and salinity, leading this project to serve as a potential model for coastal stormwater pond management. PMID:17368919

  12. Dispersion of plutonium from contaminated pond sediments

    USGS Publications Warehouse

    Rees, T.F.; Cleveland, J.M.; Carl, Gottschall W.

    1978-01-01

    Sediment-water distributions of plutonium as a function of pH and contact time are investigated in a holding pond at the Rocky Flats plant of the Department of Energy. Although plutonium has been shown to sorb from natural waters onto sediments, the results of this study indicate that under the proper conditions it can be redispersed at pH 9 and above. Concentrations greater than 900 pCi Pu/L result after 34 h contact at pH 11 or 12 and the distribution coefficient, defined as the ratio of concentration in the sediment to that in the liquid, decreases from 1.1 ?? 105 at pH 7 to 1.2 ?? 103 at pH 11. The plutonium is probably dispersed as discrete colloids or as hydrolytic species adsorbed onto colloidal sediment particles whose average size decreases with increasing pH above pH 9. About 5% of the total plutonium is dispersed at pH 12, and the dispersion seems to readsorb on the sediment with time. Consequently, migration of plutonium from the pond should be slow, and it would be difficult to remove this element completely from pond sediment by leaching with high pH solutions. ?? 1978 American Chemical Society.

  13. Salton Sea Solar Pond Power Plant Design Study and Regional Applicability

    NASA Technical Reports Server (NTRS)

    French, R. L.

    1984-01-01

    Ormat collected and organized the data base and conducted conceptual plant design, performance, and cost analysis. JPL conducted site-specific studies related to solar pond chemistry, soil biological activity, and dike design and construction. WESTEC conducted environmental investigation studies and performed an environmental assessment. SCE provided planning support for licensing and permitting and technical evaluations of the system design and cost estimate.

  14. Rapid Sand Filtration for Best Practical Treatment of Domestic Wastewater Stabilization Pond Effluent

    ERIC Educational Resources Information Center

    Boatright, D. T.; Lawrence, C. H.

    1977-01-01

    The technical and economic feasibility of constructing and operating a rapid sand filtration sewage treatment system as an adjunct to a waste water stabilization pond is investigated. The study concludes that such units are within the technical and economic constraints of a small community and comply with the EPA criteria. (BT)

  15. A trap panel for in-pond raceways to capture escaped catfish

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The first commercial-scale in-pond raceway system (IPRS) used to produce catfish in west Alabama was constructed from funds by a joint effort involving the Alabama Catfish Producers Association, Dean Wilson Farms, and Auburn University. The goal of this project was to improve profitability of catfis...

  16. Impact of Beaver Pond Colonization History on Methylmercury Concentrations in Surface Water.

    PubMed

    Levanoni, Oded; Bishop, Kevin; Mckie, Brendan G; Hartman, Göran; Eklöf, Karin; Ecke, Frauke

    2015-11-01

    Elevated concentrations of methylmercury (MeHg) in freshwater ecosystems are of major environmental concern in large parts of the northern hemisphere. Beaver ponds have been identified as a potentially important source of MeHg. The role of beavers might be especially pronounced in large parts of Europe, where beaver populations have expanded rapidly following near-extirpation. This study evaluates the role of the age and colonization history (encompassing patterns of use and reuse) of ponds constructed by the Eurasian beaver Castor fiber in regulating MeHg concentrations in Swedish streams. In 12 beaver systems located in three regions, we quantified MeHg concentrations together with other relevant parameters on five occasions per year in 2012-2013. Five were pioneer systems, inundated for the first time since beaver extirpation, and seven were recolonized, with dams reconstructed by newly recolonizing beavers. MeHg concentrations in pioneer but not in recolonized beaver systems were up to 3.5 fold higher downstream than upstream of the ponds, and varied between seasons and years. Our results show that pioneer inundation by beavers can increase MeHg concentrations in streams, but that this effect is negligible when dams are reconstructed on previously used ponds. We therefore expect that the recovery and expansion of beavers in the boreal system will only have a transitional effect on MeHg in the environment. PMID:26450629

  17. Reclamation of saline soils by partial ponding: Simulations for different soils

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A traditional method of reclaiming salt-affected soils involves ponding water on a field and leaching salts from the soil through a subsurface tile drainage system. Because water and salts move more slowly in areas midway between drain lines than in areas near the drains, achieving a desired level o...

  18. Calcium-based flue gas desulfurization sludge disposal ponds. Final report

    SciTech Connect

    Ainsworth, C.C.; Rai, D.; Resch, C.T.

    1994-04-01

    Four flue gas desulfurization (FGD) sludge disposal ponds at coal-fired power plants employing calcium (Ca)-based FGD scrubbing systems were selected for sampling and characterization. Two of the power plants use forced-air oxidation (FAO). Samples of inflow, pond water, and FGD sludge solids were obtained at each site and analyzed using on-site and laboratory techniques to characterize pond chemistry and microbiology, and to identify common or distinguishing biogeochemical reactions that affect the long-term disposal of FGD sludge. Dense populations of heterotrophic, anaerobic bacteria capable of reducing sulfate (SO{sub 4}{sup 2{minus}}) to sulfide (S{sup 2{minus}}) were observed in all sampled Ca-based FGD sludges. The chemical composition of the pond and pore waters included adequate concentrations of dissolved organic carbon for bacterial metabolism. Regardless of predisposal treatment the sludge sediments the sludge sediments developed a greatly reduced anaerobic environment, probably due to microbial activity and low gas permeability; the low redox potential of the sludge was conducive to dissimilatory microbial reduction of SO{sub 4}{sup 2{minus}} to S{sup 2{minus}}. The results suggest that regardless of the type of coal burned in electric power generation, the kind of Ca-based scrubbing material used, or use of forced air oxidation prior to disposal, certain biogeochemical reactions are generic to controlling the leachate chemistry of FGD sludge ponds. Aside from the generic chemical precipitation reactions noted above, the microbial production of sulfide appears to be common to all the ponds that were investigated. As a consequence of this sulfide production, aqueous concentrations of trace metals such as Pb, Zn, Cu, Hg, Cd, etc. will be controlled by the precipitation of the metal-sulfide minerals.

  19. Serum estrogenicity and biological responses in African catfish raised in wastewater ponds in Ghana.

    PubMed

    Asem-Hiablie, S; Church, C D; Elliott, H A; Shappell, N W; Schoenfuss, H L; Drechsel, P; Williams, C F; Knopf, A L; Dabie, M Y

    2013-10-01

    Reuse of wastewater for aquaculture improves the efficient use of water and promotes sustainability but the potential effects of endocrine disrupting compounds including estrogens in wastewater are an emerging challenge that needs to be addressed. We examined the biological effects of wastewater-borne estrogens on African catfish (Clarias gariepinus) raised in a wastewater stabilization pond (WSP) of a functioning municipal wastewater treatment plant, a wastewater polishing pond (WWP) of a dysfunctional treatment plant, and a reference pond (RP) unimpacted by wastewater, located in Ghana. Measurements of estrogen concentrations in pond water by liquid chromatography/tandem mass spectrometry showed that mean 17 β-estradiol concentrations were higher in the wastewater ponds (WWP, 6.6 ng/L±2.7 ng/L; WSP, 4.9 ng/L±1.0) than the reference (RP, 3.4±1.1 ng/L). Estrone concentrations were found to be highest in the WSP (7.8 ng/L±1.7) and lowest in the WWP (2.2 ng/L±2.4) with the RP intermediate (4.7±5.0). Fish serum estrogenicity assayed by E-SCREEN was significantly higher in female vs. male catfish in the RP and WSP but not in the WWP (p≤0.05). Histological examination of liver and gonad tissue showed no apparent signs of intersex or pathology in any ponds. The similarities in various measures of body indices between fish of this study and African catfish from freshwater systems suggest that aquaculture may be a suitable reuse option for treated municipal wastewater. PMID:23849063

  20. Environmental Projects. Volume 8: Modifications of wastewater evaporation ponds

    NASA Technical Reports Server (NTRS)

    1989-01-01

    The Goldstone Deep Space Communications Complex (GDSCC), located in the Mojave Desert about 45 miles north of Barstow, California, and about 160 miles northeast of Pasadena, is part of NASA's Deep Space Network, one of the world's largest and most sensitive scientific telecommunications and radio navigation networks. The Goldstone Complex is managed, technically directed, and operated for NASA by the Jet Propulsion Laboratory (JPL) of the California Institute of Technology in Pasadena, California. Activities at the GDSCC are carried out in support of seven parabolic dish antennas. These activities may give rise to environmental hazards: use of hazardous chemicals, asbestos, and underground storage tanks as well as the generation of hazardous wastes and the disposal of wastewater. Federal, state, and local laws governing the management of hazardous substances, asbestos, underground storage tanks and wastewater disposal have become so complex there is a need to devise specific programs to comply with the many regulations that implement these laws. In support of the national goal of the preservation of the environment and the protection of human health and safety, NASA, JPL, and the GDSCC have adopted a position that their operating installations shall maintain a high level of compliance with these laws. One of the environmental problems at the GDSCC involved four active, operational, wastewater evaporation ponds designed to receive and evaporate sewage effluent from upstream septic tank systems. One pair of active wastewater evaporation ponds is located at Echo Site, while another operational pair is at Mars Site.

  1. A biotic survey of Lovets Pond, Jackson County, Illinois

    SciTech Connect

    Peterson, M.J.

    1988-12-01

    Systematic collecting of the vascular flora, fishes, and aquatic macroinvertebrates in a natural floodplain pond ecosystem in Jackson County, Illinois, yielded 328, 17, and 93 taxa, respectively. The habitat and relative abundance of each collected specimen were recorded. Five distinct natural communities were identified in the 60-ha ecosystem and were described in detail, namely, pond, shrub swamp, true swamp, marsh, and wet-mesic flood-plain forest. With the exception of the floodplain forest all natural communities at the site were rare in the region, largely due to the extensive wetland drainage and land clearing for agricultural use. Slight disturbance to the study area appear to have had little significant impact on the site's overall natural quality. The character of the system compared favorably with the earliest known presettlement descriptions. The privately owned natural area is endangered because of the likelihood of draining and clearing for agriculture. Based on this study the site is a significant natural area of preservation. 22 refs., 5 figs.

  2. Hydrologic modeling of detention pond

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Urban watersheds produce an instantaneous response to rainfall. That results in stormwater runoff in excess of the capacity of drainage systems. The excess stormwater must be managed to prevent flooding and erosion of streams. Management can be achieved with the help of structural stormwater Best...

  3. Novel Polarization Techniques and Instrumentation for Glacial Melt Pond Laser Bathymetry

    NASA Astrophysics Data System (ADS)

    Barton-Grimley, R. A.; Gisler, A.; Thayer, J. P.; Stillwell, R. A.; Grigsby, S.; Crowley, G.

    2015-12-01

    Melt ponds contribute significantly to the feedback processes that serve to amplify the polar response to climate change. A substantial volume of melt water is found in shallow ponds during the Arctic summer on the Greenland Ice Sheet, which have consequences on glacial dynamics and ice loss, however, the water content and subsurface topography of the ponds has proven difficult to measure. The need for instrumentation to provide high-resolution depth measurements in shallow water is addressed by utilizing novel polarization discrimination techniques in a high repetition rate, low power, 532nm photon counting lidar system. Recent advances demonstrate the ability to achieve kHz acquisition rates with a depth precision of 1cm. Use of this technique eliminates the necessity for short laser pulses and high-bandwidth detectors and instead provides a less complex, smaller, and more economical solution to airborne lidar instrumentation. Recent deployment of the lidar system aboard the NASA DC-8 research aircraft, during the 2015 NASA SARP campaign, provided critical engineering data and experience to facilitate further advancement of an airborne bathymetric lidar system for melt pond studies. Signal performance from flight indicates a 50 cm horizontal ground resolution at nominal altitudes below 1000 feet above ground level, and also indicates that maintaining a vertical precision of 1cm is achievable, though these results will be further examined. Results from the DC-8 aircraft deployment are promising, and the modest system size opens up the possibility for future integration into a UAS. This presentation will highlight the measurement capabilities of this novel lidar system, and explore polarization scattering properties of laser light with snow, ice, liquid water. System performance metrics will be evaluated for operating during summer periods in the Polar Regions and discuss the scientific contribution to Cryosphere research - most notably the depth and subsurface ice

  4. Nitrogen mass balance across pilot-scale algae and duckweed-based wastewater stabilisation ponds.

    PubMed

    Zimmo, O R; van der Steen, N P; Gijzen, H J

    2004-02-01

    Nitrogen removal processes and nitrogen mass balances in algae-based ponds (ABPs) and duckweed (Lemna gibba)-based ponds (DBPs) were assessed during periods of 4 months, each under different operational conditions. During periods 1 and 2, the effect of cold and warm temperature was studied. During periods 2 and 3, the effect of low- and high-system organic loading (OL) was studied in warm seasons operation. The pilot-scale systems consisted of four similar ponds in series fed with domestic sewage with hydraulic retention time of 7 days in each pond. Overall nitrogen removal was higher during warm temperature in both ABPs and DBPs, but similar during periods 2 and 3. Nitrogen removal in DBPs was lower than in ABPs by 20%, 12% and 8% during cold temperature, warm temperature and high-OL periods, respectively. Depending on temperature and OL rate, ABPs showed higher nitrogen removal via sedimentation (46-245% higher) compared to DBPs. Also, ABPs also showed higher nitrogen removal via denitrification (7-37% higher) compared to DBPs. Ammonia volatilisation in both systems did not exceed 1.1% of influent total nitrogen during the entire experimental period. N uptake by duckweed corresponds to 30% of the influent nitrogen during warm/low OL period and decreased to 10% and 19% during the cold and warm/high OL period, respectively. Predictive models for nitrogen removal presented a good reflection of nitrogen fluxes on overall nitrogen balance under the prevailing experimental conditions. PMID:14769411

  5. The effect of water oxygen content on the production of greenhouse gases from shallow pond sediments

    NASA Astrophysics Data System (ADS)

    Freer, Adam; Quinton, John; Surridge, Ben; McNamara, Niall

    2014-05-01

    Shallow lakes and ponds, including those commonly found in agricultural landscapes are often only a few metres deep, with surface areas <1ha. Despite this, landscapes may contain a high number of these ponds, amounting to a considerable cumulative surface area. Many of these features, both naturally formed and man-made, receive and trap runoff with high nutrient and sediment loadings. As such, the potential for the production of greenhouse gases (GHGs) through biogeochemical cycling in the pond sediments may be significant. Furthermore, the abundance of available nutrients coupled with the shallow physical characteristics of these systems, mean that short, irregular eutrophic episodes during the summer are common, causing large fluctuations in the oxygen content of the overlying water column. The oxygen content of the water column is often cited as key factor in the production of GHGs in large lake and reservoir systems. Given the limited research focusing on shallow ponds/lakes, and potential for these systems to be important sources of GHGs, the impacts of variable water oxygen content should be investigated. Here we present the results from a sediment microcosm experiment utilising sediment cores from an agricultural pond system in Cumbria, UK. Intact sediment cores were incubated in the dark at in-situ temperature and continuously fed with filtered pond water for 2 weeks. During this time the oxygen content of the water was manipulated between fully oxygenated and anaerobic. Measurements of GHG release were based on calculated dissolved gas concentrations present in the water columns of these cores. Results indicated that during times of water column anoxia, production of methane and carbon dioxide increased significantly, despite the presence of substantial quantities of nitrate in the water columns. No change in N2O production was detected. These results indicate that while representing a significant cumulative carbon store in agricultural landscapes, shallow

  6. Limited influence of local and landscape factors on finescale gene flow in two pond-breeding amphibians.

    PubMed

    Coster, Stephanie S; Babbitt, Kimberly J; Cooper, Andrew; Kovach, Adrienne I

    2015-02-01

    Dispersal and gene flow within animal populations are influenced by the composition and configuration of the landscape. In this study, we evaluated hypotheses about the impact of natural and anthropogenic factors on genetic differentiation in two amphibian species, the spotted salamander (Ambystoma maculatum) and the wood frog (Lithobates sylvaticus) in a commercial forest in central Maine. We conducted this analysis at two scales: a local level, focused on factors measured at each breeding pond, and a landscape level, focused on factors measured between ponds. We investigated the effects of a number of environmental factors in six categories including Productivity, Physical, Land Composition, Land Configuration, Isolation and Location. Embryos were sampled from 56 spotted salamander breeding ponds and 39 wood frog breeding ponds. We used a hierarchical Bayesian approach in the program GESTE at each breeding pond and a random forest algorithm in conjunction with a network analysis between the ponds. We found overall high genetic connectivity across distances up to 17 km for both species and a limited effect of natural and anthropogenic factors on gene flow. We found the null models best explained patterns of genetic differentiation at a local level and found several factors at the landscape level that weakly influenced gene flow. This research indicates multiscale investigations that incorporate local and landscape factors are valuable for understanding patterns of gene flow. Our findings suggest that dispersal rates in this system are high enough to minimize genetic structuring and that current forestry practices do not significantly impede dispersal. PMID:25580642

  7. Evaluation of design factors for a cascade aerator to enhance the efficiency of an oxidation pond for ferruginous mine drainage.

    PubMed

    Oh, Chamteut; Ji, Sangwoo; Cheong, Youngwook; Yim, Giljae; Hong, Ji-Hye

    2016-10-01

    This research focused on the optimum design of a cascade aerator to enhance the efficiency of an oxidation pond in a passive treatment system for remediating ferruginous mine drainage. For this purpose, various aeration experiments with aerators of different drop heights (0-4 m) and formations (types A and B) were executed on mine drainage. Type A simply drops the mine drainage into the oxidation pond while type B sprays the mine drainage and retains it for 8 min in each step. The efficiency enhancement of the oxidation pond was strongly dependent on the increase in pH and DO of the mine drainage discharged into the pond. The water quality improved with the increase in drop height but especially showed better effect with type B. The reasons for this result were attributed to the increase of contact surface and retention time of the mine drainage. The cascade aerator, therefore, should be designed to be as high as possible with the assistance of spraying form and retention time of the mine drainage to maximize the efficiency of the oxidation pond. These effects could be evaluated by calculating required areas of the oxidation pond for 95% of Fe(2+) oxidation. PMID:26936197

  8. Effect of anaerobic pretreatment on environmental and physicochemical characteristics of duckweed based stabilization ponds.

    PubMed

    Caicedo, J R; Espinosa, C; Andrade, M; Gijzen, H

    2002-01-01

    Duckweed based stabilization ponds, an alternative for wastewater treatment, are attracting a growing interest from researchers because they are basically a low cost technology, easy to built and operate, and produce tertiary quality effluents. Besides, this technology offers the possibility of resource recovery by producing high quality duckweed protein, which can be of further use. Since the technology is rather new, there are many aspects to be studied before its full-scale implementation. It is necessary to gain sound knowledge of the basic principles of the complex processes occurring in the system, as well as of the practical aspects of design and operation. The presence of a layer of duckweed on the surface is expected to produce different environmental and physicochemical conditions in the water from those found in conventional stabilization ponds. These environmental and physicochemical conditions affect both plant growth and biological treatment processes in the system, therefore it is important to determine their behavior in a duckweed system and how they can be affected by an anaerobic pretreatment. Continuous flow pilot plants composed of seven ponds in series were operated with artificial substrate under two different conditions: with anaerobic pretreatment and without anaerobic pretreatment. The flow was kept constant during the operation. Conditions such as pH, temperature, dissolved oxygen, alkalinity, conductivity, chemical oxygen demand, biochemical oxygen demand, total and ammonium nitrogen, nitrites and nitrates, and phosphorus were evaluated in the system under steady state conditions. The main conclusions from the study include the following: pH, temperature and oxygen profiles are more stable in duckweed ponds than in conventional stabilization ponds; anaerobic pretreatment has a significant effect on the oxygen concentration in the system and on the organic matter removal but not on the nutrient removal. PMID:11833735

  9. On solar ponds: salty fare for the world's energy appetite

    SciTech Connect

    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.

  10. Use of aquatic vegetation to improve sediment pond efficiency

    SciTech Connect

    Martin, J.F.; Janiak, H.

    1982-12-01

    The US Environmental Protection Agency (EPA) is supporting research in Poland aimed at improving the efficiency of surface mine sedimentation ponds. Mine water from large, open-pit lignite mines in Poland requires treatment for suspended solids removal prior to discharge. One technique being investigated for suspended solids removal involves the use of vegetation growing in the sediment ponds. This paper describes the results of research at two, small sedimentation ponds and the operating characteristics of three, full-scale sediment removal ponds at the newly developed Belchatow Mine. Topics investigated during the project include: selection of grasses; growth characteristics of grasses; sediment removal efficiency; and design criteria for full-scale installations.

  11. 7. William E. Barrett, Photographer, August 1975. LOG PONDS LOOKING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. William E. Barrett, Photographer, August 1975. LOG PONDS LOOKING WEST FROM POWERHOUSE ROOF. TRANSFORMER SHED IN FOREGROUND. - Meadow River Lumber Company, Highway 60, Rainelle, Greenbrier County, WV

  12. Performance of pond-wetland complexes as a preliminary processor of drinking water sources.

    PubMed

    Wang, Weidong; Zheng, Jun; Wang, Zhongqiong; Zhang, Rongbin; Chen, Qinghua; Yu, Xinfeng; Yin, Chengqing

    2016-01-01

    Shijiuyang Constructed Wetland (110 hm(2)) is a drinking water source treatment wetland with primary structural units of ponds and plant-bed/ditch systems. The wetland can process about 250,000 tonnes of source water in the Xincheng River every day and supplies raw water for Shijiuyang Drinking Water Plant. Daily data for 28 months indicated that the major water quality indexes of source water had been improved by one grade. The percentage increase for dissolved oxygen and the removal rates of ammonia nitrogen, iron and manganese were 73.63%, 38.86%, 35.64%, and 22.14% respectively. The treatment performance weight of ponds and plant-bed/ditch systems was roughly equal but they treated different pollutants preferentially. Most water quality indexes had better treatment efficacy with increasing temperature and inlet concentrations. These results revealed that the pond-wetland complexes exhibited strong buffering capacity for source water quality improvement. The treatment cost of Shijiuyang Drinking Water Plant was reduced by about 30.3%. Regional rainfall significantly determined the external river water levels and adversely deteriorated the inlet water quality, thus suggesting that the "hidden" diffuse pollution in the multitudinous stream branches as well as their catchments should be the controlling emphases for river source water protection in the future. The combination of pond and plant-bed/ditch systems provides a successful paradigm for drinking water source pretreatment. Three other drinking water source treatment wetlands with ponds and plant-bed/ditch systems are in operation or construction in the stream networks of the Yangtze River Delta and more people will be benefited. PMID:26899651

  13. Effects on ground-water quality of seepage from a phosphatic clayey waste settling pond, north-central Florida

    USGS Publications Warehouse

    Hunn, J.D.; Seaber, P.R.

    1986-01-01

    Water samples were taken from test wells drilled near an inactive phosphatic clayey waste storage settling pond, from the settling pond and its perimeter ditch, and from an active settling pond near White Springs, Hamilton County, in north-central Florida. The purpose was to document the seepage of chemical constituents from the inactive settling pond and ditch into the adjacent surficial groundwater system, and to assess the potential for movement of these constituents into the deeper Floridan aquifer system which is the major source of public supply in the area. The study area is underlain by a 2 ,500-ft-thick sequence of Coastal Plain sediments of Early Cretaceous to Holocene age. The rocks of Tertiary and Quaternary age that underlie the test site area can be grouped into three major geohydrologic units. In descending order, these units are: surficial aquifer, Hawthorn confining unit, and Floridan aquifer system. Phosphate deposits occur in the upper part of the surficial aquifer. Water in the active settling pond is a calcium magnesium sulfate type with a dissolved solids concentration of 250 mg/L, containing greater amounts of phosphorus, iron, aluminum, barium, zinc, and chromium than the other surface waters. Water in the perimeter ditch is a calcium sulfate type with a dissolved solids concentration of 360 to 390 mg/L, containing greater amounts of calcium, sulfate, nitrogen, and fluoride than other surface waters. Water from the inactive settling pond is a calcium magnesium bicarbonate type with a dissolved solids concentration of 140 mg/L, containing more bicarbonate than the other surface waters. Large amounts of chemical constituents in the phosphate waste disposal slurry are apparently trapped in the sediments of the settling ponds. The quality of water in the upper part of the surficial aquifer from wells within 200 to 400 ft of the inactive settling pond shows no signs of chemical contamination from phosphate industry operations. The horizontal

  14. Fourteen Years of Pond Monitoring in Boreal Plain, northern Alberta, Canada: The effects of climate variability and harvesting practices

    NASA Astrophysics Data System (ADS)

    Abnizova, A.; Devito, K. J.; Petrone, R. M.

    2013-12-01

    Western Boreal forest of Canada is experiencing rapid increase in rates of cumulative impacts of disturbance for resource extraction, climate change and forest fires. To understand their sensitivity and response to multi-decadal natural and anthropogenic disturbances a long-term (1998-2013) and extensive pond ecosystem monitoring has been conducted on the Boreal Plains at the Utikuma Region Study Area (URSA) (56o N, 115o W). Hydrological, chemical and nutrient data were collected along a forest-peatland-pond transect in a paired catchment aspen harvest study in the area underlain by fine-grained till moraines glacial deposits. The aims of this study were (1) to identify the main characteristics in pond hydrologic regime, specifically water level dynamics, both seasonally and between years; (2) to identify factors controlling variation in measured hydro-chemistry and nutrients; and (3) to provide evidence on how water quality conditions in the ponds are changing on long (multi-year to decadal) time scales in response to harvesting practices and climatic trends during wet and dry cycles. No difference in pond or catchment hydrologic and hydro-chemical response was observed between harvested and reference sites pre- or post- harvesting. Wetland and pond waters were not affected by the harvesting practices due to lack of hydrologic connectivity between pond and forest systems. The hydrologic relationship between forestlands and open-water wetlands is a response in their water balance differences driven by their storage characteristics. Temporal trends in ponds' water levels, chemical and nutrient concentrations during the 14 year record were most closely related to relative connectivity to groundwater systems and flow direction in response to climatic cycles and vegetation water use and were the most useful parameters for characterizing duration and type of connectivity during wet and dry cycles. Using empirical relationships from such long-term monitoring, this study

  15. Impact of sludge layer geometry on the hydraulic performance of a waste stabilization pond.

    PubMed

    Ouedraogo, Faissal R; Zhang, Jie; Cornejo, Pablo K; Zhang, Qiong; Mihelcic, James R; Tejada-Martinez, Andres E

    2016-08-01

    Improving the hydraulic performance of waste stabilization ponds (WSPs) is an important management strategy to not only ensure protection of public health and the environment, but also to maximize the potential reuse of valuable resources found in the treated effluent. To reuse effluent from WSPs, a better understanding of the factors that impact the hydraulic performance of the system is needed. One major factor determining the hydraulic performance of a WSP is sludge accumulation, which alters the volume of the pond. In this study, computational fluid dynamics (CFD) analysis was applied to investigate the impact of sludge layer geometry on hydraulic performance of a facultative pond, typically used in many small communities throughout the developing world. Four waste stabilization pond cases with different sludge volumes and distributions were investigated. Results indicate that sludge distribution and volume have a significant impact on wastewater treatment efficiency and capacity. Although treatment capacity is reduced with accumulation of sludge, the latter may induce a baffling effect which causes the flow to behave closer to that of plug flow reactor and thus increase treatment efficiency. In addition to sludge accumulation and distribution, the impact of water surface level is also investigated through two additional cases. Findings show that an increase in water level while keeping a constant flow rate can result in a significant decrease in the hydraulic performance by reducing the sludge baffling effect, suggesting a careful monitoring of sludge accumulation and water surface level in WSP systems. PMID:27176549

  16. Southwest region solar pond study for three sites: Tularosa Basin, Malaga Bend, and Canadian River

    SciTech Connect

    Boegli, W.J.; Dahl, M.M.; Remmers, H.E.

    1984-08-01

    In the study, the Bureau of Reclamation investigated the technical and economic feasibility of using solar salt-gradient ponds to generate power and to produce freshwater in Bureau projects at three sites--the Canadian River at Logan, New Mexico; Malaga Bend on the Pecos River near Carlsbad, New Mexico; and the Tularosa Basin in the vicinity of Alamogordo, New Mexico. The ponds would be used to generate electric power that could be integrated with the Bureau's power grid or used in combination with thermal energy from the ponds to power commercially available desalination systems to produce freshwater. Results of the economic analysis, which concentrated primarily on the Tularosa Basin site, showed that solar-pond-generated intermediate load power would cost between 62 and 90 mills/kWh and between 52 and 83 mills/kWh for baseload power. This results in benefit-cost ratios of approximately 2.0 and 1.3 for intermediate and baseload, respectively, when compared to similar facilities powered by fossil fuels. The cost savings are even more pronounced when comparing the two (solar versus fossil fuel) as a source of power for conventional distillation and membrane-type desalination systems.

  17. Disappearing Arctic tundra ponds: Fine-scale analysis of surface hydrology in drained thaw lake basins over a 65 year period (1948-2013)

    NASA Astrophysics Data System (ADS)

    Andresen, Christian G.; Lougheed, Vanessa L.

    2015-03-01

    Long-term fine-scale dynamics of surface hydrology in Arctic tundra ponds (less than 1 ha) are largely unknown; however, these small water bodies may contribute substantially to carbon fluxes, energy balance, and biodiversity in the Arctic system. Change in pond area and abundance across the upper Barrow Peninsula, Alaska, was assessed by comparing historic aerial imagery (1948) and modern submeter resolution satellite imagery (2002, 2008, and 2010). This was complemented by photogrammetric analysis of low-altitude kite-borne imagery in combination with field observations (2010-2013) of pond water and thaw depth transects in seven ponds of the International Biological Program historic research site. Over 2800 ponds in 22 drained thaw lake basins (DTLB) with different geological ages were analyzed. We observed a net decrease of 30.3% in area and 17.1% in number of ponds over the 62 year period. The inclusion of field observations of pond areas in 1972 from a historic research site confirms the linear downward trend in area. Pond area and number were dependent on the age of DTLB; however, changes through time were independent of DTLB age, with potential long-term implications for the hypothesized geomorphologic landscape succession of the thaw lake cycle. These losses were coincident with increases in air temperature, active layer, and density and cover of aquatic emergent plants in ponds. Increased evaporation due to warmer and longer summers, permafrost degradation, and transpiration from encroaching aquatic emergent macrophytes are likely the factors contributing to the decline in surface area and number of ponds.

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

    USGS Publications Warehouse

    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.

  19. Comparison of ammonia volatilisation rates in algae and duckweed-based waste stabilisation ponds treating domestic wastewater.

    PubMed

    Zimmo, O R; van der Steen, N P; Gijzen, H J

    2003-11-01

    Quantification of ammonia volatilisation from wastewater stabilisation ponds is important in order to understand its significance for overall nitrogen removal in these widely applied low-cost treatment systems. Ammonia volatilisation rates were measured in pilot plant facilities consisting of one line of four algae-based ponds in series and a parallel line of four ponds with a floating mat of duckweed (Lemna gibba). Ammonia volatilisation was assessed during a period of one and a half years. The method applied is accurate, convenient and is proposed for analysis of a wide range of gasses emitted from stabilisation ponds and possibly other aquatic systems. The ammonia volatilisation rates in algae-based ponds (ABPs) were higher than in duckweed-based ponds (DBPs). This can be explained by the lower values of NH(3) in DBPs due to shading and lower pH values, since the volatilisation rate highly correlated with free ammonia concentration (NH(3)) in pond water. The duckweed cover appeared not to provide a physical barrier for volatilisation of unionised ammonia, because whenever NH(3) concentrations were equal in ABP and DBP also the volatilisation rates were equal. Volatilisation was in the range of 7.2-37.4 mg-Nm(-2)d(-1) and 6.4 -31.5 mg-Nm(-2)d(-1) in the ABPs and DBPs, respectively. Average influent and effluent ammonium nitrogen measurements showed that the ammonia volatilisation during the study period in any system did not exceed 1.5% of total ammonium nitrogen removal. Therefore this study confirmed results from simultaneous experimental work in our laboratory indicating that nitrification/denitrification, rather than ammonia volatilisation, is the most important mechanism for N removal in ABPs and DBPs. PMID:14568043

  20. Ecosystem function in waste stabilisation ponds: Improving water quality through a better understanding of biophysical coupling

    NASA Astrophysics Data System (ADS)

    Ghadouani, Anas; Reichwaldt, Elke S.; Coggins, Liah X.; Ivey, Gregory N.; Ghisalberti, Marco; Zhou, Wenxu; Laurion, Isabelle; Chua, Andrew

    2014-05-01

    Wastewater stabilisation ponds (WSPs) are highly productive systems designed to treat wastewater using only natural biological and chemical processes. Phytoplankton, microbial communities and hydraulics play important roles for ecosystem functionality of these pond systems. Although WSPs have been used for many decades, they are still considered as 'black box' systems as very little is known about the fundamental ecological processes which occur within them. However, a better understanding of how these highly productive ecosystems function is particularly important for hydrological processes, as treated wastewater is commonly discharged into streams, rivers, and oceans, and subject to strict water quality guidelines. WSPs are known to operate at different levels of efficiency, and treatment efficiency of WSPs is dependent on physical (flow characteristics and sludge accumulation and distribution) and biological (microbial and phytoplankton communities) characteristics. Thus, it is important to gain a better understanding of the role and influence of pond hydraulics and vital microbial communities on pond performance and WSP functional stability. The main aim of this study is to investigate the processes leading to differences in treatment performance of WSPs. This study uses a novel and innovative approach to understand these factors by combining flow cytometry and metabolomics to investigate various biochemical characteristics, including the metabolite composition and microbial community within WSPs. The results of these analyses will then be combined with results from the characterisation of pond hydrodynamics and hydraulic performance, which will be performed using advanced hydrodynamic modelling and advanced sludge profiling technology. By understanding how hydrodynamic and biological processes influence each other and ecosystem function and stability in WSPs, we will be able to propose ways to improve the quality of the treatment using natural processes, with

  1. Beaver ponds' impact on fluvial processes (Beskid Niski Mts., SE Poland).

    PubMed

    Giriat, Dorota; Gorczyca, Elżbieta; Sobucki, Mateusz

    2016-02-15

    Beaver (Castor sp.) can change the riverine environment through dam-building and other activities. The European beaver (Castor fiber) was extirpated in Poland by the nineteenth century, but populations are again present as a result of reintroductions that began in 1974. The goal of this paper is to assess the impact of beaver activity on montane fluvial system development by identifying and analysing changes in channel and valley morphology following expansion of beaver into a 7.5 km-long headwater reach of the upper Wisłoka River in southeast Poland. We document the distribution of beaver in the reach, the change in river profile, sedimentation type and storage in beaver ponds, and assess how beaver dams and ponds have altered channel and valley bottom morphology. The upper Wisłoka River fluvial system underwent a series of anthropogenic disturbances during the last few centuries. The rapid spread of C. fiber in the upper Wisłoka River valley was promoted by the valley's morphology, including a low-gradient channel and silty-sand deposits in the valley bottom. At the time of our survey (2011), beaver ponds occupied 17% of the length of the study reach channel. Two types of beaver dams were noted: in-channel dams and valley-wide dams. The primary effect of dams, investigated in an intensively studied 300-m long subreach (Radocyna Pond), was a change in the longitudinal profile from smooth to stepped, a local reduction of the water surface slope, and an increase in the variability of both the thalweg profile and surface water depths. We estimate the current rate of sedimentation in beaver ponds to be about 14 cm per year. A three-stage scheme of fluvial processes in the longitudinal and transverse profile of the river channel is proposed. C. fiber reintroduction may be considered as another important stage of the upper Wisłoka fluvial system development. PMID:26657380

  2. 30 CFR 817.56 - Postmining rehabilitation of sedimentation ponds, diversions, impoundments, and treatment...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... ponds, diversions, impoundments, and treatment facilities. 817.56 Section 817.56 Mineral Resources... Postmining rehabilitation of sedimentation ponds, diversions, impoundments, and treatment facilities. Before... removed and reclaimed, and that all permanent sedimentation ponds, diversions, impoundments, and...

  3. 30 CFR 816.56 - Postmining rehabilitation of sedimentation ponds, diversions, impoundments, and treatment...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... ponds, diversions, impoundments, and treatment facilities. 816.56 Section 816.56 Mineral Resources... rehabilitation of sedimentation ponds, diversions, impoundments, and treatment facilities. Before abandoning a... and reclaimed, and that all permanent sedimentation ponds, diversions, impoundments, and...

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

    PubMed Central

    Rybak, Fanny; Depraetere, Marion; Gasc, Amandine; Le Viol, Isabelle; Pavoine, Sandrine; Sueur, Jérôme

    2015-01-01

    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. PMID:26587351

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

    PubMed

    Desjonquères, Camille; Rybak, Fanny; Depraetere, Marion; Gasc, Amandine; Le Viol, Isabelle; Pavoine, Sandrine; Sueur, Jérôme

    2015-01-01

    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. PMID:26587351

  6. 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

    USGS Publications Warehouse

    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.

  7. The aquatic fate of triclopyr in whole-pond treatments

    USGS Publications Warehouse

    Petty, D.G.; Skogerboe, J.G.; Getsinger, K.D.; Foster, D.R.; Houtman, B.A.; Fairchild, J.F.; Anderson, L.W.

    2001-01-01

    The aquatic fate of the triethylamine salt formulation of triclopyr (3,5,6-trichloro-2-pyridinyloxyacetic acid) was determined in whole-pond applications in closed (no water exchange) systems in California, Missouri and Texas in two studies conducted in 1995 and 1996. These studies determined dissipation rates of triclopyr and its principal metabolites, 3,5,6-trichloropyridinol (tcp) and 3,5,6-trichloro-2-methoxypyridine (tmp) in water, sediment and finfish. Ponds at each site containing a healthy biological community were treated at 2.5 mg AE litre-1 triclopyr. Water and sediment samples were collected through 12 weeks post-treatment, and non-target animals were collected through 4 weeks post-treatment. Dissipation rates for triclopyr, TCP and TMP were similar at each of the study sites, despite differences in weather, water quality, biotic community, light transmission and geographic location. Half-lives of triclopyr in water ranged from 5.9 to 7.5 days, while those of TCP and TMP ranged from 4 to 8.8 and 4 to 10 days, respectively. Levels of triclopyr and TCP declined in sediments at half-lives ranging from 2.8 to 4.6 days and 3.8 to 13.3 days, respectively. No TMP was detected in sediment. Triclopyr and TCP cleared from fish in relation to concentrations found in the water column. TMP levels in fish were generally an order of magnitude higher than levels of triclopyr and TCP, particularly in the visceral portion of the animals. No adverse effects on water quality or on the non-target biotic community were found following triclopyr applications. Results of these studies were comparable to those of triclopyr dissipation studies conducted in reservoirs, lakes and riverine systems in Georgia, Florida, Minnesota and Washington, indicating that the degradation and dissipation of triclopyr and its metabolites are similar in representative systems throughout the USA. ?? 2001 Society of Chemical Industry.

  8. The aquatic fate of triclopyr in whole-pond treatments.

    PubMed

    Petty, D G; Skogerboe, J G; Getsinger, K D; Foster, D R; Houtman, B A; Fairchild, J F; Anderson, L W

    2001-09-01

    The aquatic fate of the triethylamine salt formulation of triclopyr (3,5,6-trichloro-2-pyridinyloxyacetic acid) was determined in whole-pond applications in closed (no water exchange) systems in California, Missouri and Texas in two studies conducted in 1995 and 1996. These studies determined dissipation rates of triclopyr and its principal metabolites, 3,5,6-trichloropyridinol (TCP) and 3,5,6-trichloro-2-methoxypridine (TMP) in water, sediment and finfish. Ponds at each site containing a healthy biological community were treated at 2.5 mg AE litre-1 triclopyr. Water and sediment samples were collected through 12 weeks post-treatment, and non-target animals were collected through 4 weeks post-treatment. Dissipation rates for triclopyr, TCP and TMP were similar at each of the study sites, despite differences in weather, water quality, biotic community, light transmission and geographic location. Half-lives of triclopyr in water ranged from 5.9 to 7.5 days, while those of TCP and TMP ranged from 4 to 8.8 and 4 to 10 days, respectively. Levels of triclopyr and TCP declined in sediments at half-lives ranging from 2.8 to 4.6 days and 3.8 to 13.3 days, respectively. No TMP was detected in sediment. Triclopyr and TCP cleared from fish in relation to concentrations found in the water column. TMP levels in fish were generally an order of magnitude higher than levels of triclopyr and TCP, particularly in the visceral portion of the animals. No adverse effects on water quality or on the non-target biotic community were found following triclopyr applications. Results of these studies were comparable to those of triclopyr dissipation studies conducted in reservoirs, lakes and riverine systems in Georgia, Florida, Minnesota and Washington, indicating that the degradation and dissipation of triclopyr and its metabolites are similar in representative systems throughout the USA. PMID:11561400

  9. Evaluation of remedial alternatives for the Solar Ponds Plume, Rocky Flats Environmental Technology Site

    SciTech Connect

    Hranac, K.C.; Chromec, F.W.; Fiehweg, R.; Hopkins, J.

    1998-07-01

    This paper describes the process used to select a remedial alternative for handling contaminated groundwater emanating from the Solar Evaporation Ponds (Solar Ponds) at the Rocky Flats Environmental Technology Site (RFETS) and prevent it from reaching the nearest surface water body, North Walnut Creek. Preliminary results of field investigations conducted to provide additional information for the alternatives analysis are also presented. The contaminated groundwater is referred to as the Solar Ponds Plume (SPP). The primary contaminants in the SPP are nitrate and uranium; however, some metals exceed the site action levels at several locations and volatile organic compounds, originating from other sources, also have been detected. Currently the SPP, local surface water runoff, and infiltrated precipitation are collected by a trench system located downgradient of the Solar Ponds and pumped to three storage tanks. The water (two to three million gallons annually) is then pumped to an on-site treatment plant for evaporation at an approximate cost of $7.57 per liter.

  10. Decline in recycled water quality during short-term storage in open ponds.

    PubMed

    Higgins, Jennifer; Warnken, Jan; Teasdale, Peter R; Arthur, J Michael

    2009-12-01

    Changes were assessed in urban wastewater treatment plant (WWTP) effluent quality during short-term storage in open surface ponds. Water quality was monitored over five years at the inlets and outlets of open storage ponds located at three biological nutrient removal plants. Pond influent temperature, rainfall and sewage inflow were not found to be major factors. However, there was a trend for water temperature to be correlated negatively with nitrogenous nutrient and positively with faecal coliform values. The observed increases in faecal coliforms, nutrients and chemical oxygen demand were most likely caused through avian faecal contamination. These increases challenge the notion that pond storage has a positive or negligible effect on effluent quality. The observed one to two orders of magnitude increase in faecal coliforms may affect reuse scheme viability by limiting the range of uses under Australian water recycling guidelines. Potential improvements to short-term recycled water storage management at WWTPs could include the integration of monitoring requirements in WWTP discharge licences and recycling guidelines and the monitoring of all water quality parameters, including microbiological ones, at the point of entry into the recycled water distribution system, after WWTP storage, rather than directly post-disinfection. PMID:19590127

  11. Guano-Derived Nutrient Subsidies Drive Food Web Structure in Coastal Ponds.

    PubMed

    Vizzini, Salvatrice; Signa, Geraldina; Mazzola, Antonio

    2016-01-01

    A stable isotope study was carried out seasonally in three coastal ponds (Marinello system, Italy) affected by different gull guano input to investigate the effect of nutrient subsidies on food web structure and dynamics. A marked 15N enrichment occurred in the pond receiving the highest guano input, indicating that gull-derived fertilization (guanotrophication) had a strong localised effect and flowed across trophic levels. The main food web response to guanotrophication was an overall erosion of the benthic pathway in favour of the planktonic. Subsidized primary consumers, mostly deposit feeders, switched their diet according to organic matter source availability. Secondary consumers and, in particular, fish from the guanotrophic pond, acted as couplers of planktonic and benthic pathways and showed an omnivorous trophic behaviour. Food web structure showed substantial variability among ponds and a marked seasonality in the subsidized one: an overall simplification was evident only in summer when guano input maximises its trophic effects, while higher trophic diversity and complexity resulted when guano input was low to moderate. PMID:26953794

  12. Guano-Derived Nutrient Subsidies Drive Food Web Structure in Coastal Ponds

    PubMed Central

    Vizzini, Salvatrice; Signa, Geraldina; Mazzola, Antonio

    2016-01-01

    A stable isotope study was carried out seasonally in three coastal ponds (Marinello system, Italy) affected by different gull guano input to investigate the effect of nutrient subsidies on food web structure and dynamics. A marked 15N enrichment occurred in the pond receiving the highest guano input, indicating that gull-derived fertilization (guanotrophication) had a strong localised effect and flowed across trophic levels. The main food web response to guanotrophication was an overall erosion of the benthic pathway in favour of the planktonic. Subsidized primary consumers, mostly deposit feeders, switched their diet according to organic matter source availability. Secondary consumers and, in particular, fish from the guanotrophic pond, acted as couplers of planktonic and benthic pathways and showed an omnivorous trophic behaviour. Food web structure showed substantial variability among ponds and a marked seasonality in the subsidized one: an overall simplification was evident only in summer when guano input maximises its trophic effects, while higher trophic diversity and complexity resulted when guano input was low to moderate. PMID:26953794

  13. Comparing the performances of circular ponds with different impellers by CFD simulation and microalgae culture experiments.

    PubMed

    Meng, Chen; Huang, Jianke; Ye, Chunyu; Cheng, Wenchao; Chen, Jianpei; Li, Yuanguang

    2015-07-01

    In this study, a numerical simulation using computational fluid dynamics (CFD) was used to investigate the hydrodynamic characteristics of circular ponds with three different impellers (hydrofoil, four-pitched-blade turbine, and grid plate). The reliability of the CFD model was validated by particle image velocimetry (PIV). Hydrodynamic analyses were conducted to evaluate the average velocity magnitude along the light direction (Uz), turbulence properties, average shear stress, pressure loss and the volume percentage of dead zone inside circular ponds. The simulation results showed that Uz value of hydrofoil was 58.9, 40.3, and 28.8% higher than those of grid plate with single arm, grid plate with double arms and four-pitched blade turbines in small-scale circular ponds, respectively. In addition, hydrofoil impeller with down-flow operation had outstanding mixing characteristics. Lastly, the results of Chlorella pyrenoidosa cultivation experiments indicated that the biomass concentration of hydrofoil impeller with down-flow operation was 65.2 and 88.8% higher than those of grid plate with double arms and four-pitched-blade turbine, respectively. Therefore, the optimal circular pond mixing system for microalgae cultivation involved a hydrofoil impeller with down-flow operation. PMID:25680396

  14. Evidence for ponding and catastrophic floods in central Valles Marineris, Mars

    USGS Publications Warehouse

    Harrison, K.P.; Chapman, M.G.

    2008-01-01

    The Valles Marineris canyon system of Mars is closely related to large flood channels, some of which emerge full born from chaotic terrain in canyon floors. Coprates Chasma, one of the largest Valles Marineris canyons, is connected at its west end to Melas Chasma and on its east end to chaotic terrain-filled Capri and Eos Chasmata. The area from central Melas to Eos Chasmata contains a 1500 km long and about 1 km deep depression in its floor. Despite the large volumes of groundwater that likely discharged from chaotic terrain in this depression, no evidence of related fluvial activity has thus far been reported. We present an analysis of the regional topography which, together with photogeologic interpretation of available imagery, suggests that ponding due to late Hesperian discharge of water possibly produced a lake (mean depth 842 m) spanning parts of the Valles Marineris depression (VMD). Overflow of this lake at its eastern end resulted in delivery of water to downstream chaos regions and outflow channels. Our ponding hypothesis is motivated primarily by the identification of scarp and terrace features which, despite a lateral spread of about 1500 km, have similar elevations. Furthermore, these elevations correspond to the maximum ponding elevation of the region (-3560 m). Simulated ponding in the VMD yields an overflow point at its eastern extremity, in Eos Chasma. The neighborhood of this overflow point contains clear indicators of fluvial erosion in a consistent east-west orientation. ?? 2008 Elsevier Inc.

  15. Predicting waste stabilization pond performance using an ecological simulation model

    SciTech Connect

    New, G.R.

    1987-01-01

    Waste stabilization ponds (lagoons) are often favored in small communities because of their low cost and ease of operation. Most models currently used to predict performance are empirical or fail to address the primary lagoon cell. Empirical methods for predicting lagoon performance have been found to be off as much as 248 percent when used on a system other than the one they were developed for. Also, the present models developed for the primary cell lack the ability to predict parameters other than biochemical oxygen demand (BOD) and nitrogen. Oxygen consumption is usually estimated from BOD utilization. LAGOON is a fortran program which models the biogeochemical processes characteristic of the primary cell of facultative lagoons. Model parameters can be measured from lagoons in the vicinity of a proposed lagoon or estimated from laboratory studies. The model was calibrated utilizing a subset of the Corinne Utah lagoon data then validated utilizing a subset of the Corinne Utah data.

  16. The ripple pond: enabling spiking networks to see

    PubMed Central

    Afshar, Saeed; Cohen, Gregory K.; Wang, Runchun M.; Van Schaik, André; Tapson, Jonathan; Lehmann, Torsten; Hamilton, Tara J.

    2013-01-01

    We present the biologically inspired Ripple Pond Network (RPN), a simply connected spiking neural network which performs a transformation converting two dimensional images to one dimensional temporal patterns (TP) suitable for recognition by temporal coding learning and memory networks. The RPN has been developed as a hardware solution linking previously implemented neuromorphic vision and memory structures such as frameless vision sensors and neuromorphic temporal coding spiking neural networks. Working together such systems are potentially capable of delivering end-to-end high-speed, low-power and low-resolution recognition for mobile and autonomous applications where slow, highly sophisticated and power hungry signal processing solutions are ineffective. Key aspects in the proposed approach include utilizing the spatial properties of physically embedded neural networks and propagating waves of activity therein for information processing, using dimensional collapse of imagery information into amenable TP and the use of asynchronous frames for information binding. PMID:24298234

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

    USGS Publications Warehouse

    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.

  18. Carbon trace gases in lake and beaver pond ice near Thompson, Manitoba, Canada

    NASA Astrophysics Data System (ADS)

    Kuhlbusch, Thomas A. J.; Zepp, Richard G.

    1999-11-01

    Concentrations of CO2, CO, and CH4 were measured in beaver pond and lake ice in April 1996 near Thompson, Manitoba to derive information on possible impacts of ice melting on corresponding atmospheric trace gas concentrations. CH4 concentrations in beaver pond and lake ice ranged between 0.3-150 mmol m-3 and 3.1-56.2 μmol m-3, respectively. The corresponding CO concentrations showed no significant differences between the two lakes. They varied between 50 and 250 μmol m-3. These CO concentrations are some of the highest determined in any aquatic system. The differences in CH4 concentrations between lake and pond can be explained by the differences in production and microbial oxidation rates between the two systems. No explanation can be given for the similar CO concentrations. Supersaturation factors for CO were 660±130 and 630±330, and 65-35000 and 0.6-13 for CH4 in the ice of the beaver pond and Troy Lake, respectively. When digging into the beaver pond ice, a continuous flow of bubbles with 0.32±0.06 vol% CH4, 2.2±0.3 vol% CO2, and 482±98 ppb CO coming out of the slash ice for about 20-30 minutes was noticed. Wintertime flux estimates of CH4 and CO showed that they represent at minimum 6.4% and 2.2% of that of the summer. It has to be noted that these wintertime fluxes will mostly be released to the atmosphere during the time of snowmelt, thus a limited time period of weeks.

  19. Development of a Fully Coupled Transient Double-Diffusive Convective Model: Application to a Salinity-Gradient Solar Pond

    NASA Astrophysics Data System (ADS)

    Suarez, F.; Tyler, S. W.; Childress, A. E.

    2008-12-01

    A solar pond is a water body which is heated by absorption of solar radiation and which can provide long- term thermal storage for collected energy. To avoid large heat losses, convection must be suppressed close to the top of the pond. A salinity-gradient solar pond (SGSP) is an artificially stratified solar pond consisting of three thermally distinctive layers: the upper convective zone (UCZ), the non-convective zone (NCZ), and the lower convective zone (LCZ). The UCZ is a relatively thin layer of "cold" and "fresh" water. In the NCZ, the salt gradient suppresses convection within the pond, and thus, the NCZ acts as insulation for the LCZ. The LCZ is the layer where the salt concentration and temperature are the highest. The solar radiation that penetrates the pond's upper layers reaches the LCZ, which can approach temperatures greater than 90°C. Modeling the fluid dynamics of this system is difficult because it requires solution of a set of three second- order non-linear partial differential equations. In order to evaluate the thermal performance and stability of an SGSP, numerical simulation of both heat and mass are required but challenging as double-diffusive convection is likely to occur. Previous approaches have typically assumed no convective transport of solutes, which led to static salinity boundaries of the layers within the SGSP. A 2-D fully coupled numerical model that evaluates the transient performance of an SGSP is introduced. The model simulates the coupled momentum, heat, and mass transfer within the pond. The model can evaluate the influence of meteorological conditions on pond performance by properly describing the heat fluxes through the surface and the solar radiation absorption within the pond, which are typically not well included. Preliminary results show that in a one-week period, for a 1.0 m depth SGSP under summer conditions and without heat extraction, the thicknesses of the UCZ and LCZ increases from 0.1 to 0.2 m, and from 0.5 to 0

  20. Delayed feeding of channel catfish fry stocked in ponds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We compared production variables between channel catfish, Ictalurus punctatus, nursery ponds fed according to industry standards, that is feeding immediately at stocking, to an alternative practice of delaying feeding for 6 wk after stocking in an effort to utilize natural pond productivity and redu...

  1. Gauging the Health of New England's Lakes and Ponds

    EPA Science Inventory

    The New England Lakes and Ponds Project provides a consistent and first time comprehensive assessment of the ecological and water quality condition of lakes and ponds across the New England region. The project is being conducted by EPA along with the New England Interstate Water...

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

    EPA Science Inventory

    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...

  3. Origin and flatness of ponds on asteroid 433 Eros

    NASA Astrophysics Data System (ADS)

    Roberts, James H.; Kahn, Eliezer G.; Barnouin, Olivier S.; Ernst, Carolyn M.; Prockter, Louise M.; Gaskell, Robert W.

    2014-10-01

    NEAR-Shoemaker Multi-Spectral Imager data reveal several hundred "ponds" on 433 Eros: smooth deposits that sharply embay the bounding depressions in which they lie, and whose spectra appear blue relative to that of the surrounding terrain. We investigate the topography of these ponds on Eros using a new shape model derived from stereophotoclinometric analysis, and validated against altimetry from the NEAR Laser Rangefinder, to constrain the mode of pond formation from three existing models. We update the locations of 55 pond candidates identified in images registered to the new shape model. We classify the flatness of these features according to the behavior of the first and second derivatives of the topography. We find that less than half of pond candidates have clearly flat floors. Based on the pond topography, we favor an external origin for the ponds' deposits. We suggest that fine dust may be transported into bounding depressions by electrostatic levitation, but may adhere to slopes, and that seismic shaking may not be sufficient to bring the deposits to an equipotential surface. Disaggregation of a central boulder should result in an obvious break in slope, such a variation is only observed in roughly half the pond candidates.

  4. Some basic considerations and possible improvements on the solar pond

    SciTech Connect

    Sha, W.T.; Cha, Y.S.; Liu, K.V.; Soo, S.L.

    1980-06-01

    Experimental results were compared to theoretical stability criteria of a salt gradient solar pond. Cellular motion in the non-convective layer is expected. Innovative concepts on friction stabilization using stabilizing barriers and longitudinal stratification to improve pond heat extraction efficiency are presented.

  5. Amphibian Oasis: Designing and Building a Schoolyard Pond.

    ERIC Educational Resources Information Center

    Gosselin, Heather; Johnson, Bob

    1996-01-01

    Building a pond in a schoolyard is a rewarding way to help boost local populations of amphibians, to increase the natural value of school grounds, and to serve as a locale for observing the life cycles of plants, invertebrates, and amphibians. This article outlines important considerations in designing and building a pond from siting through…

  6. Effect of pond ash on pen surface properties

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Maintaining adequate feedlot pen surfaces is expensive. Pond ash (PA), a coal-fired electrical generation by-product, has good support qualities. A study was conducted comparing the performance of pond ash (PA) surfaced pens with soil surface (SS) pens. Four pens of an eight pen series with dimensio...

  7. Fate of permethrin in model outdoor ponds

    SciTech Connect

    Rawn, G.P.; Webster, G.R.; Muir, D.C.

    1982-01-01

    In 1979 and 1980, outdoor artificial ponds were treated with /sup 14/C-permethrin (labelled at either the cyclopropyl or methylene position) at 0.028 kg/ha (15 ug/L). Uptake of permethrin by duckweed and hydrosoil was monitored by direct combustion, TLC-autoradiography, HPLC, and liquid scintillation counting. Rapid loss of permethrin from the water coincided with the detection of five degradation products in the water at concentrations below 2.0 ug/L. The products were cis- and trans-cyclopropyl acid, phenoxybenzoic acid, and phenoxybenzyl alcohol, and an unknown non-cleaved product of permethrin. Permethrin was readily sorbed by duckweed but was not persistent. Permethrin residues in the hydrosoil, which was the major sink for permethrin added to the ponds, were persistent and were detected at 420 days post-treatment. Cis-permethrin was more persistent in the hydrosoil than the trans-permethrin. The results indicated that permethrin in water was short-lived at an application rate of 15 ug/L because of the rapid degradation of permethrin in the water and sorption of permethrin by the hydrosoil and vegetation. However, at one year post-treatment, permethrin residues were still detected in the hydrosoil at 1.0 ug/kg.

  8. Historic macrophyte development in Par Pond

    SciTech Connect

    Grace, J.B.

    1985-08-01

    Aerial photographs from 1975, 1980, and 1983 were examined to evaluate the changes that have occurred in the wetland vegetation of Par Pond, a reactor-cooling reservoir. Evaluation of the aerial photographs was based on comparisons with ground-level vegetation maps made during July 1984. Comparisons of photographs from August and December of 1983 revealed the main seasonal change in the aerial coverage of wetland vegetation to be the wintertime loss of non-persistent emergent species such as Nelumbo lutea and Nymphaea odorata. Comparisons between September 1980 and August 1983 revealed that the lakeward extent of non-persistent macrophytes has increased by an average of 8.2 m, though not all sites have changed equally. For persistent macrophytes (principally Typha), the average increase in lakeward extent between December 1975 and August 1983 was 3.48 m. The extensive development of wetland vegetation in Par Pond as well as the substantial spread of vegetation over only a few years time indicates the high suitability of this habitat for the growth of wetland plants.

  9. 2101-M Pond hydrogeologic characterization report

    SciTech Connect

    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.

  10. Densification of pond ash by blasting

    SciTech Connect

    Gandhi, S.R.; Dey, A.K.; Selvam, S.

    1999-10-01

    Fly ash from thermal power plants is disposed, in huge quantities in ash ponds, which occupy large land areas otherwise useful for agriculture, housing, or other development. For effective rehabilitation of ash ponds, densification of the slurry deposit is essential to increase the bearing capacity and to improve its resistance to liquefaction. Extensive field trials were carried out to evaluate the effectiveness of deep blasting for densification of deposited fly ash. Ninety explosions comprising 15 single blasts, with varying depths and quantities of charges, and 3 group blasts, each having 25 charges placed at various spacings, were carried out. The compaction achieved in terms of an increase in relative density was evaluated from surface settlement measurements. Extensive field monitoring was undertaken through pore-water pressure measurements, vibration measurements, penetration tests, and block vibration tests. For the average charge of 2--4 g of explosive per cubic meter of untreated deposit, the average relative density was found to improve from 50% to 56--58%. Analysis of the test results indicates that deep blasting may be an effective technique for modest compaction of loose fly ash deposits. The field testing program presented in this paper provides valuable information that can be used for planning blast densification of fly ash deposits.

  11. Simple wastewater treatment (UASB reactor, shallow polishing ponds, coarse rock filter) allowing compliance with different reuse criteria.

    PubMed

    von Sperling, M; de Andrada, J G B

    2006-01-01

    UASB reactors followed by polishing ponds comprise simple and economic wastewater treatment systems, capable of reaching very high removal efficiencies of pathogenic organisms, leading to the potential use of the effluent for unrestricted irrigation. However, for other types of reuse (urban and industrial), ponds are limited in the sense of producing effluents with high suspended solids (algae) concentrations. The work investigates a system with coarse rock filters for polishing the pond effluent. The overall performance of the system is analyzed, together with the potential for different types of reuse. The excellent results obtained (mean effluent concentrations: BOD: 27 mg/L; SS: 26 mg/L; E. coli: 450 MPN/100 mL) indicate the possibility of unrestricted use of the effluent for agriculture and restricted urban and industrial uses, according to WHO and USEPA. PMID:17302321

  12. Solar ponds in alkaline lake and oil well regions

    SciTech Connect

    Lodhi, M.A.K.

    1996-05-01

    Solar ponds are probably the simplest technology available for useful conversion of solar energy. The basic technology is proven. Solar ponds have been shown to be technically feasible and economically viable for many applications particularly for thermal use. The electrical conversion and use of solar energy via solar ponds is still questionable in general for economic viability. By putting the untapped sources together in the South Plains region it looks promising economically both for thermal and electrical conversions and applications. There are a number of alkaline lake basins randomly scattered in the South Plains region of the USA. In that area there are thousands of crude oil producing wells which produce brine in abundance. Selection of suitable alkaline lake basins as a solar pond site and as depository sites of brine from oil wells and using of this brine and salty water from alkaline lakes makes the solar pond economically viable for both thermal and electrical demands in the area.

  13. Crossing the final ecological threshold in high Arctic ponds

    PubMed Central

    Smol, John P.; Douglas, Marianne S. V.

    2007-01-01

    A characteristic feature of most Arctic regions is the many shallow ponds that dot the landscape. These surface waters are often hotspots of biodiversity and production for microorganisms, plants, and animals in this otherwise extreme terrestrial environment. However, shallow ponds are also especially susceptible to the effects of climatic changes because of their relatively low water volumes and high surface area to depth ratios. Here, we describe our findings that some high Arctic ponds, which paleolimnological data indicate have been permanent water bodies for millennia, are now completely drying during the polar summer. By comparing recent pond water specific conductance values to similar measurements made in the 1980s, we link the disappearance of the ponds to increased evaporation/precipitation ratios, probably associated with climatic warming. The final ecological threshold for these aquatic ecosystems has now been crossed: complete desiccation. PMID:17606917

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

    NASA Technical Reports Server (NTRS)

    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.

  15. Infection status with trematode metacercariae in pond smelts, Hypomesus olidus.

    PubMed

    Nam, H S; Sohn, W M

    2000-03-01

    Many Koreans usually eat raw pond smelts, Hypomesus olidus, in the winter. This study was performed to evaluate the infection status with trematode metacercariae in pond smelts from January 1998 through February 1999. Among 1,305 fish collected, 459 were purchased from wholesale dealers in Chinchon-gun, Chungchongbuk-do, and the rest of them were caught with a casting net in Soyangho (Lake), Taehoman (Bay) and Paekkokchosuchi (Pond). Seven species of trematode metacercariae including two unidentified ones were detected from 1,305 pond smelts. The number of detected trematode metacercariae according to the species are as follow: Clonorchis sinensis 8, Holostephanus nipponicus 7, Cyathocotyle orientalis 24, Diplostomum sp. 14, and Metorchis orientalis 7. From the above results, it was confirmed that H. olidus plays a role as the second intermediate host of some kinds of trematode including C. sinensis in Korea. Our report shows possible clonorchiasis caused by eating raw pond smelts. PMID:10743358

  16. Crossing the final ecological threshold in high Arctic ponds.

    PubMed

    Smol, John P; Douglas, Marianne S V

    2007-07-24

    A characteristic feature of most Arctic regions is the many shallow ponds that dot the landscape. These surface waters are often hotspots of biodiversity and production for microorganisms, plants, and animals in this otherwise extreme terrestrial environment. However, shallow ponds are also especially susceptible to the effects of climatic changes because of their relatively low water volumes and high surface area to depth ratios. Here, we describe our findings that some high Arctic ponds, which paleolimnological data indicate have been permanent water bodies for millennia, are now completely drying during the polar summer. By comparing recent pond water specific conductance values to similar measurements made in the 1980s, we link the disappearance of the ponds to increased evaporation/precipitation ratios, probably associated with climatic warming. The final ecological threshold for these aquatic ecosystems has now been crossed: complete desiccation. PMID:17606917

  17. Factors Influencing Fecal Contamination in Pond of Bangladesh

    NASA Astrophysics Data System (ADS)

    Knappett, P. S.; Escamilla, V.; Layton, A.; McKay, L. D.; Emch, M.; Mailloux, B. J.; Williams, D. E.; Huq, M. R.; Alam, M.; Farhana, L.; Ferguson, A. S.; Sayler, G. S.; Ahmed, K.; Serre, M. L.; Akita, Y.; Yunus, M.; van Geen, A.

    2010-12-01

    Occurrence of diarrheal disease in villages in rural Bangladesh remains relatively common, even though many households have switched to tubewell water for drinking and cooking. One factor contributing to this may be exposure to fecal contamination in ponds, which are often used for bathing and fishing. The objective of this study is to determine the dominant sources of fecal pollution in typical ponds and to explore the relationship between local population, latrine density, latrine quality and concentrations of fecal bacteria and pathogens in pond water. Forty-three ponds were sampled and analyzed for E. coli using culture-based methods and for E. coli, Bacteroides and adenovirus using quantitative PCR. Population and sanitation infrastructure were surveyed and compared to levels of pond fecal contamination. Molecular fecal source tracking using Bacteroides, determined that humans were the dominant source of fecal contamination in 79% of the ponds. Ponds directly receiving latrine effluent had the highest concentrations of fecal indicator bacteria. Concentrations of fecal indicator bacteria correlated with population surveyed within a distance of 30-70 m (p<0.01) and total latrines surveyed within 50-70 m (p<0.05). Unsanitary latrines with visible effluent within the pond drainage basin were also significantly correlated to fecal indicator concentrations (p<0.05). The vast majority of the surveyed ponds contained unsafe levels of fecal contamination primarily due to unsanitary latrines, and to lesser extent to sanitary latrines and cattle. Since the majority of fecal pollution is from humans, use of pond water could help explain the persistence of diarrheal disease in rural Bangladesh.

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

    PubMed

    Waajen, Guido W A M; Faassen, Elisabeth J; Lürling, 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 survey on cyanobacterial blooms and studied three ponds in detail. Among 3,500 urban ponds in the urbanized Dutch province of North Brabant, 125 showed cyanobacterial blooms in the period 2009-2012. This covered 79% of all locations registered for cyanobacterial blooms, despite the fact that urban ponds comprise only 11% of the area of surface water in North Brabant. Dominant bloom-forming genera in urban ponds were Microcystis, Anabaena and Planktothrix. In the three ponds selected for further study, the microcystin concentration of the water peaked at 77 μg l(-1) and in scums at 64,000 μg l(-1), which is considered highly toxic. Microcystin-RR and microcystin-LR were the most prevalent variants in these waters and in scums. Cyanobacterial chlorophyll-a peaked in August with concentrations up to 962 μg l(-1) outside of scums. The ponds were highly eutrophic with mean total phosphorus concentrations between 0.16 and 0.44 mg l(-1), and the sediments were rich in potential releasable phosphorus. High fish stocks dominated by carp lead to bioturbation, which also favours blooms. As urban ponds in North Brabant, and likely in other regions, regularly suffer from cyanobacterial blooms and citizens may easily have contact with the water and may ingest cyanobacterial material during recreational activities, particularly swimming, control of health risk is of importance. Monitoring of cyanobacteria and cyanobacterial toxins in urban ponds is a first step to control health risks. Mitigation strategies should focus on external sources of eutrophication and consider the effect of sediment P release and bioturbation by fish. PMID:24798921

  19. Impact of permafrost thaw on Arctic tundra pond geochemistry

    NASA Astrophysics Data System (ADS)

    Reyes, F.; Lougheed, V.

    2012-12-01

    Increasing evidence indicates the arctic tundra is changing physically, biologically, and chemically due to climate warming. With a warmer climate, permafrost is expected to thaw and influence the chemistry of arctic aquatic ecosystems. However, knowledge is limited on how geochemistry of arctic tundra pond ecosystems will respond. By re-sampling historical IBP ponds in Barrow, AK first sampled in the 1970s, previous studies have shown an increase in water temperature, nutrients and algal biomass through time. Results from this study indicate an increase of Ca, Mg, and Na in the water column, and a decrease in pH relative to the 1970s, suggesting an increased rate and magnitude of carbonate and Mg release. Seasonal trends were also examined to understand what processes, such as mineral weathering, peat decomposition and evaporation, were currently most influential in determining pond geochemistry. An increase in Ca/Na molar ratios, and carbonate and magnesium concentrations indicates that these tundra ponds are experiencing greater carbonate weathering compared to the 1970s and the rate of carbonate weathering increases in ponds as the summer progresses. However, increasing dissolved organic carbon (DOC) concentrations originating from peat decomposition are likely neutralizing additional inputs of carbonate, causing pond pH to decrease and exacerbating mineral weathering. A strong positive relationship between element concentrations and active layer pond thaw depth suggests that the origin of these additional solutes is likely from permafrost thaw. Active layer thaw depth has increased substantially over the past 40 years in the IBP ponds. Chloride/Bromide molar ratios and Deuterium/ 18-Oxygen isotope ratios will be used to determine the degree of evaporation occurring in tundra ponds. Ultimately, this study provides evidence for how geochemistry can identify the sources of chemical inputs to Arctic ponds affected by climate change and permafrost thaw.

  20. Sensitivity to acidification of subalpine ponds and lakes in north-western Colorado

    NASA Astrophysics Data System (ADS)

    Campbell, D. H.; Muths, E.; Turk, J. T.; Corn, P. S.

    2004-10-01

    processes in the water column and at the sediment-water interface. These results indicate that conceptual and mechanistic acidification models that have been developed for lakes and streams may be inadequate for predicting acidification in less-understood systems such as ponds.

  1. Increasing Dissolved Organic Carbon (DOC) in Arctic tundra ponds over the past 40 years

    NASA Astrophysics Data System (ADS)

    Lougheed, V.; Contreras, G.; Andresen, C. G.; Miller, N. A.; Reyes, F. R.

    2013-12-01

    With a warming Arctic, permafrost is expected to thaw and active layer depth to increase, thus releasing organic material and nutrients into aquatic environments; however, there are few long-term datasets with which to test these predictions in aquatic ecosystems. The Arctic tundra ponds at the International Biological Program (IBP) site in Barrow, Alaska, studied for the first time in the 1970s, represent one of the very few locations in the Arctic where long-term data are available on freshwater ecosystem structure and function. The objective of this study was to determine whether Dissolved Organic Carbon (DOC) concentrations in Arctic tundra ponds had changed over time, how changes in thaw depth and temperature have impacted DOC quantity, and what the consequences of any changes have been for aquatic ecosystems. Over the summers of 2010-13 we collected water samples and measured thaw depth from 5 IBP ponds and compared these with data from the 1970s. Ponds were 2°C warmer and thaw depth was up to 19cm deeper in the 2000s as compared to the 1970s. Release of organic (e.g. DOC) and inorganic compounds (e.g.nitrogen) from formerly frozen organic ground into the ponds was associated with the increased thaw depth. For example, DOC was significantly higher in 2009-2012 compared to the 1970s; this was most notable later in the growing season. Similarly, incubations experiments indicate a steady rise in DOC released from permafrost with warming. DOC is likely a relatively conservative tracer of permafrost thaw in aquatic systems, and thus was a better predictor of increased phytoplankton levels than inorganic nutrients. This study will add to our understanding of the changes that warmer temperatures and altered aquatic environments bring to the Arctic and the consequences for carbon budgets in northern latitudes.

  2. Carryover aquatic effects on survival of metamorphic frogs during pond emigration

    USGS Publications Warehouse

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

    2006-01-01

    In organisms with complex life cycles, physiological stressors during early life stages may have fitness-level impacts that are delayed into later stages or habitats. We tested the hypothesis that body size and date of metamorphosis, which are highly responsive to aquatic stressors, influence post-metamorphic survival and movement patterns in the terrestrial phase of an ephemeral pond-breeding frog by examining these traits in two populations of northern red-legged frogs (Rana aurora aurora). To increase variation of body size at metamorphosis, we manipulated food availability for 314 of 1045 uniquely marked tadpoles and estimated the probability that frogs survived and emigrated using concentric rings of drift fencing surrounding ponds and Bayesian capture-recapture modeling. The odds of surviving and emigrating from the ponds to the innermost drift fences, ???12 m, increased by factors of 2.20 (95% credibility intervals 1.39-4.23) and 2.54 (0.94-4.91) with each millimeter increase in snout-vent length and decreased by factors of 0.91 (0.85-0.96) and 0.89 (0.80-1.00) with each day's delay in metamorphosis for the two ponds. The odds of surviving and moving to the next ring of fencing, 12 m to ???40 m from the ponds, increased by a factor of 1.20 (0.45-4.06) with each millimeter increase in size. Our results demonstrated that body size and timing of metamorphosis relate strongly to the performance of newly metamorphosed frogs during their initial transition into terrestrial habitat. Carryover effects of aquatic stressors that reduce size and delay metamorphosis may have population-level impacts that are not expressed until terrestrial stages. Since changes in both aquatic and terrestrial systems are implicated in many amphibian declines, quantifying both immediate and delayed effects of stressors on demographic rates is critical to sound management. ?? 2006 by the Ecological Society of America.

  3. Fuel Pond Sludge - Lessons Learned from Initial De-sludging of Sellafield's Pile Fuel Storage Pond - 12066

    SciTech Connect

    Carlisle, Derek; Adamson, Kate

    2012-07-01

    The Pile Fuel Storage Pond (PFSP) at Sellafield was built and commissioned between the late 1940's and early 1950's as a storage and cooling facility for irradiated fuel and isotopes from the two Windscale Pile reactors. The pond was linked via submerged water ducts to each reactor, where fuel and isotopes were discharged into skips for transfer along the duct to the pond. In the pond the fuel was cooled then de-canned underwater prior to export for reprocessing. The plant operated successfully until it was taken out of operation in 1962 when the First Magnox Fuel Storage Pond took over fuel storage and de-canning operations on the site. The pond was then used for storage of miscellaneous Intermediate Level Waste (ILW) and fuel from the UK's Nuclear Programme for which no defined disposal route was available. By the mid 1970's the import of waste ceased and the plant, with its inventory, was placed into a passive care and maintenance regime. By the mid 1990s, driven by the age of the facility and concern over the potential challenge to dispose of the various wastes and fuels being stored, the plant operator initiated a programme of work to remediate the facility. This programme is split into a number of key phases targeted at sustained reduction in the hazard associated with the pond, these include: - Pond Preparation: Before any remediation work could start the condition of the pond had to be transformed from a passive store to a plant capable of complex retrieval operations. This work included plant and equipment upgrades, removal of redundant structures and the provision of a effluent treatment plant for removing particulate and dissolved activity from the pond water. - Canned Fuel Retrieval: Removal of canned fuel, including oxide and carbide fuels, is the highest priority within the programme. Handling and export equipment required to remove the canned fuel from the pond has been provided and treatment routes developed utilising existing site facilities to

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

    SciTech Connect

    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.

  5. Results of submerged sediment core sampling and analysis on Par Pond, Pond C, and L Lake: July 1995

    SciTech Connect

    Koch, J.W. II; Martin, F.D.; Friday, G.P.

    1996-06-01

    Sediment cores from shallow and deep water locations in Par Pond, Pond C, and L Lake were collected and analyzed in 1995 for radioactive and nonradioactive constituents. This core analysis was conducted to develop a defensible characterization of contaminants found in the sediments of Par Pond, Pond C, and L Lake. Mercury was the only nonradiological constituent with a nonestimated quantity that was detected above the U.S Environmental Protection Agency Region IV potential contaminants of concern screening criteria. It was detected at a depth of 0.3--0.6 meters (1.0--2.0 feet) at one location in L Lake. Cesium-137, promethium-146, plutonium-238, and zirconium-95 had significantly higher concentrations in Par Pond sediments than in sediments from the reference sites. Cobalt-60, cesium-137, plutonium-238, plutonium-239/240, and strontium-90 had significantly higher concentrations in L-Lake sediments than sediments from the reference sites.

  6. Basal-topographic control of stationary ponds on a continuously moving landslide

    USGS Publications Warehouse

    Coe, J.A.; McKenna, J.P.; Godt, J.W.; Baum, R.L.

    2009-01-01

    The Slumgullion landslide in the San Juan Mountains of southwestern Colorado has been moving for at least the last few hundred years and has multiple ponds on its surface. We have studied eight ponds during 30 trips to the landslide between July 1998 and July 2007. During each trip, we have made observations on the variability in pond locations and water levels, taken ground-based photographs to document pond water with respect to moving landslide material and vegetation, conducted Global Positioning System surveys of the elevations of water levels and mapped pond sediments on the landslide surface. Additionally, we have used stereo aerial photographs taken in October 1939, October 1940 and July 2000 to measure topographic profiles of the eight pond locations, as well as a longitudinal profile along the approximate centerline of the landslide, to examine topographic changes over a 60- to 61-year period of time. Results from field observations, analyses of photographs, mapping and measurements indicate that all pond locations have remained spatially stationary for 60-300 years while landslide material moves through these locations. Water levels during the observation period were sensitive to changes in the local, spring-fed, stream network, and to periodic filling of pond locations by sediment from floods, hyperconcentrated flows, mud flows and debris flows. For pond locations to remain stationary, the locations must mimic depressions along the basal surface of the landslide. The existence of such depressions indicates that the topography of the basal landslide surface is irregular. These results suggest that, for translational landslides that have moved distances larger than the dimensions of the largest basal topographic irregularities (about 200 m at Slumgullion), landslide surface morphology can be used as a guide to the morphology of the basal slip surface. Because basal slip surface morphology can affect landslide stability, kinematic models and stability

  7. Heavy metal composition in stormwater and retention in ponds dependent on pond age, design and catchment type.

    PubMed

    Egemose, Sara; Sønderup, Melanie J; Grudinina, Anna; Hansen, Anders S; Flindt, Mogens R

    2015-01-01

    Heavy metals have toxic effects on flora and fauna in the aquatic environments and are of great concern in stormwater. Heavy metal runoff was studied in 37 stormwater ponds in Denmark with varying heavy metal load, catchment type and pond design. The studied metals were Cu, Cr, Cd, Pb, Ni and Zn. 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 difficult to retain. The removal efficiency in the ponds varied considerably, with the highest retention of Pb, Ni and Zn due to higher particulate fraction. The retention increased with increased pond volume-to-reduced catchment area ratio. In addition, the pond age affected the efficiency; whereas ponds less than 1-2 years efficiently removed all metals, 30-40-year-old ponds only removed Pb, Ni and Zn, but steeply decreasing over the years. Physical parameters such as pond size, age and sedimentation patterns were found to play a more significant role in the removal compared with chemical parameters 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-toxic levels, except for Cu and Cr at a few study sites. PMID:25262998

  8. Effect of Low Quality Effluent from Wastewater Stabilization Ponds to Receiving Bodies, Case of Kilombero Sugar Ponds and Ruaha River, Tanzania

    PubMed Central

    Machibya, Magayane; Mwanuzi, Fredrick

    2006-01-01

    A study was conducted in a sewage system at Kilombero Sugar Company to review its design, configuration, effectiveness and the quality of influent and effluent discharged into the Ruaha river (receiving body). The concern was that, the water in the river, after effluent has joined the river, is used as drinking water by villages located downstream of the river. Strategic sampling at the inlet of the oxidation pond, at the outlet and in the river before and after the effluent has joined the receiving body (river) was undertaken. Samples from each of these locations were taken three times, in the morning, noon and evening. The sample were then analysed in the laboratory using standard methods of water quality analysis. The results showed that the configuration and or the layout of the oxidation ponds (treatment plant) were not in accordance with the acceptable standards. Thus, the BOD5 of the effluent discharged into the receiving body (Ruaha River) was in the order of 41 mg/l and therefore not meeting several standards as set out both by Tanzanian and international water authorities. The Tanzanian water authorities, for example, requires that the BOD5 of the effluent discharged into receiving bodies be not more that 30 mg/l while the World Health Organization (WHO) requires that the effluent quality ranges between 10 – 30 mg/l. The paper concludes that proper design of treatment plants (oxidation ponds) is of outmost importance especially for factories, industries, camps etc located in rural developing countries where drinking water from receiving bodies like rivers and lakes is consumed without thorough treatment. The paper further pinpoint that both owners of treatment plants and water authorities should establish monitoring/management plan such that treatment plants (oxidation ponds) could be reviewed regarding the change on quantity of influent caused by population increase. PMID:16823095

  9. Effect of low quality effluent from wastewater stabilization ponds to receiving bodies, case of Kilombero sugar ponds and Ruaha river, Tanzania.

    PubMed

    Machibya, Magayane; Mwanuzi, Fredrick

    2006-06-01

    A study was conducted in a sewage system at Kilombero Sugar Company to review its design, configuration, effectiveness and the quality of influent and effluent discharged into the Ruaha river (receiving body). The concern was that, the water in the river, after effluent has joined the river, is used as drinking water by villages located downstream of the river. Strategic sampling at the inlet of the oxidation pond, at the outlet and in the river before and after the effluent has joined the receiving body (river) was undertaken. Samples from each of these locations were taken three times, in the morning, noon and evening. The sample were then analysed in the laboratory using standard methods of water quality analysis. The results showed that the configuration and or the layout of the oxidation ponds (treatment plant) were not in accordance with the acceptable standards. Thus, the BOD5 of the effluent discharged into the receiving body (Ruaha River) was in the order of 41 mg/l and therefore not meeting several standards as set out both by Tanzanian and international water authorities. The Tanzanian water authorities, for example, requires that the BOD5 of the effluent discharged into receiving bodies be not more that 30 mg/l while the World Health Organization (WHO) requires that the effluent quality ranges between 10 - 30 mg/l. The paper concludes that proper design of treatment plants (oxidation ponds) is of outmost importance especially for factories, industries, camps etc located in rural developing countries where drinking water from receiving bodies like rivers and lakes is consumed without thorough treatment. The paper further pinpoint that both owners of treatment plants and water authorities should establish monitoring/management plan such that treatment plants (oxidation ponds) could be reviewed regarding the change on quantity of influent caused by population increase. PMID:16823095

  10. Evaluation of performance of full-scale duckweed and algal ponds receiving septage.

    PubMed

    Papadopoulos, Frantzis H; Metaxa, Eirini G; Iatrou, Miltos N; Papadopoulos, Aristotelis H

    2014-12-01

    The performance of duckweed and algal systems in removing fecal bacteria, organic matter, and nutrients was evaluated in three full-scale ponds operating in series. Trucks collected septage from holding tanks and discharged it into the system, daily. The inflow rates varied between the warm and the cold season. Duckweed and algae naturally colonized the ponds in two successive periods of 10 and 13 months, respectively. Environmental conditions were determined at various pond depths. Without harvesting, the duckweed system was neutral and anoxic. Alkaline and oversaturation conditions were observed in the algal system. The overall removals of 5-day biochemical oxygen demand, total suspended solids, total nitrogen removal, and orthophosphate (ortho-PO4(3-)) ranged from 94 to 97, 62 to 84, 68 to 74, and 0 to 26%, respectively. The E. coli and enterococci reductions varied between 2.2 to 3.0 and 1.1 to 1.4 log units, respectively. The upper values were always associated with the algal system. PMID:25654933

  11. Aging in sexual and obligately asexual clones of Daphnia from temporary ponds.

    PubMed

    Dudycha, Jeffry L; Hassel, Christiane

    2013-03-01

    The freshwater crustacean Daphnia is an emerging model system in the biology of aging. Diversity in aging patterns is thought to be caused by ecological variation in selection on age-specific performance. Previous work in Daphnia has shown a strong correspondence between selective differences and genetic variation in aging in the Daphnia pulex species complex. However, recent evidence suggests obligate asexuality could account for the more rapid aging found in pond genotypes compared with lake genotypes without invoking differences in selection. Evolutionary biologists have to date assumed equivalent operation of neutral processes when comparing aging across populations, but a shift in the breeding system changes the basic dynamics of neutral evolution. To test the hypothesis that the breeding system could explain the short lifespans of pond-dwelling Daphnia, we compared aging of sexual and asexual Daphnia clones from temporary ponds. Our data contradict the breeding system hypothesis. Differences in aging between the breeding systems were slight, and trended in the opposite direction from that predicted: asexual clones had longer lifespans and appeared to age more slowly than sexual clones. We conclude that divergent selection between habitats remains the best explanation for differences in aging between Daphnia species. PMID:23467752

  12. Water-quality and sediment-chemistry data of drain water and evaporation ponds from Tulare Lake Drainage District, Kings County, California March 1985 to March 1986

    USGS Publications Warehouse

    Fujii, Roger

    1988-01-01

    Trace element and major ion concentrations were measured in water samples collected monthly between March 1985 and March 1986 at the MD-1 pumping station at the Tulare Lake Drainage District evaporation ponds, Kings County, California. Samples were analyzed for selected pesticides several times during the year. Salinity, as measured by specific conductance, ranged from 11,500 to 37,600 microsiemens/centimeter; total recoverable boron ranged from 4,000 to 16,000 micrg/L; and total recoverable molybdenum ranged from 630 to 2,600 microg/L. Median concentrations of total arsenic and total selenium were 97 and 2 microg/L. Atrazine, prometone, propazine, and simazine were the only pesticides detected in water samples collected at the MD-1 pumping station. Major ions, trace elements, and selected pesticides also were analyzed in water and bottom-sediment samples from five of the southern evaporation ponds at Tulare Lake Drainage District. Water enters the ponds from the MD-1 pumping station at pond 1 and flows through the system terminating at pond 10. The water samples increased in specific conductance (21,700 to 90,200 microsiemens/centimeter) and concentrations of total arsenic (110 to 420 microg/L), total recoverable boron (12,000 to 80,000 microg/L) and total recoverable molybdenum (1,200 to 5,500 microg/L) going from pond 1 to pond 10, respectively. Pesticides were not detected in water from any of the ponds sampled. Median concentrations of total arsenic and total selenium in the bottom sediments were 4.0 and 0.9 microg/g, respectively. The only pesticides detected in bottom sediment samples from the evaporation ponds were DDD and DDE, with maximum concentration of 0.8 microg/kilogram. (Author 's abstract)

  13. CO2 Efflux from Shrimp Ponds in Indonesia

    PubMed Central

    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

  14. Observational bias and the apparent distribution of ponds on Eros

    NASA Astrophysics Data System (ADS)

    Roberts, James H.; Barnouin, Olivier S.; Kahn, Eliezer G.; Prockter, Louise M.

    2014-10-01

    Over 300 “ponds” have been identified on 433 Eros: smooth deposits that sharply embay the bounding depressions in which they lie. The known ponds are largely concentrated near the equator at the ends of the long axis of the asteroid. Here, we examine the pixel scale of images available at the pond locations, and compare the observed distribution of ponds on Eros to that of the image pixel scale. We find that the majority (60%) of ponds are found in the regions covered by images with pixel scales less than 2 m/px, a total of only 13% of the surface area. The correlation between pond density and image pixel scale suggests a significant observational bias in the identification of small ponds. These findings suggest that the distribution of ponds on Eros may not be as clear-cut as previously reported, and that it may be best not to use this distribution to assess existing models regarding their formation of these landforms.

  15. Environmental selection of planktonic methanogens in permafrost thaw ponds.

    PubMed

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

    2016-01-01

    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. PMID:27501855

  16. Compartmental model for organic matter digestion in facultative ponds.

    PubMed

    Giraldo, E; Garzón, A

    2002-01-01

    A model has been developed for the digestion of organic matter in facultative ponds in tropical regions. Complete mixing has been assumed for the aerobic and anaerobic compartments. Settling, aerobic layer oxidation, and anaerobic layer methanogenesis are the main processes for organic matter removal in the water column. Exchange processes between layers are dispersive or soluble exchange, solubilization and transport of organic matter from sediments to water column are also taken into account. Degradation of organic matter in the sediments produces gaseous emissions to the water column. The exchange between bubbles ascending and the water column was measured. The model was calibrated with data obtained from a pilot facultative pond built in Muña Reservoir in Bogotá. The pond was sampled during 4 months to compare data between its water hyacinth covered section and uncovered section. The results clearly show the relative importance of different BOD removal processes in facultative ponds and suggest modifications to further improve performance. The results from the model suggest that internal loadings to facultative ponds due to solubilization and return of organic matter from the sediments to the aerobic layer greatly influence the soluble BOD effluent concentration. Aerobic degradation activity in the facultative pond does not affect significantly the effluent concentration. Anaerobic degradation activity in the facultative pond can more easily achieve increases in the removal efficiencies of BOD. PMID:11833730

  17. Environmental selection of planktonic methanogens in permafrost thaw ponds

    PubMed Central

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

    2016-01-01

    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. PMID:27501855

  18. Environmental selection of planktonic methanogens in permafrost thaw ponds

    NASA Astrophysics Data System (ADS)

    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.

  19. Solar pond research at the Los Alamos National Laboratory

    SciTech Connect

    Jones, G.F.; Meyer, K.A.; Hedstrom, J.C.; Grimmer, D.P.

    1984-01-01

    A description of solar pond research at Los Alamos National Laboratory is presented. The main issues in the theory of solar ponds are discussed. Among these are the interfacial-boundary-layer model, models for interface motion and pond performance, heat extraction, and ground heat loss. The core of the research effort at Los Alamos was the development of a one-dimensional computer program to accurately predict dynamic performance of a solar pond. The computer model and the experiments that were designed and performed to validate it are described. The experiments include two laboratory tanks wherein temperature, salinity, and flow visualization data were obtained and a 232 m/sup 2/ outdoor solar pond. Results from preliminary validation show good agreement between the pond's predicted dynamic behavior and that which actually occurred in the experiments. More validation using data from full-sized solar ponds is needed. A new correlation for the ratio of interfacial salt-flux to heat-flux is proposed which agrees well with our data. Recommendations for future research are given.

  20. 2012 Annual Industrial Wastewater Reuse Report for the Idaho National Laboratory Site's Advanced Test Reactor Complex Cold Waste Pond

    SciTech Connect

    Mike Lewis

    2013-02-01

    This report describes conditions, as required by the state of Idaho Industrial Wastewater Reuse Permit (#LA 000161 01, Modification B), for the wastewater land application site at the Idaho National Laboratory Site’s Advanced Test Reactor Complex Cold Waste Pond from November 1, 2011 through October 31, 2012. The report contains the following information: Facility and system description Permit required effluent monitoring data and loading rates Groundwater monitoring data Status of compliance activities Noncompliance issues Discussion of the facility’s environmental impacts During the 2012 permit year, approximately 183 million gallons of wastewater were discharged to the Cold Waste Pond. This is well below the maximum annual permit limit of 375 million gallons. As shown by the groundwater sampling data, sulfate and total dissolved solids concentrations are highest near the Cold Waste Pond and decrease rapidly as the distance from the Cold Waste Pond increases. Although concentrations of sulfate and total dissolved solids are elevated near the Cold Waste Pond, both parameters were below the Ground Water Quality Rule Secondary Constituent Standards in the down gradient monitoring wells.

  1. 2011 Annual Industrial Wastewater Reuse Report for the Idaho National Laboratory Site's Advanced Test Reactor Complex Cold Waste Pond

    SciTech Connect

    Mike Lewis

    2012-02-01

    This report describes conditions, as required by the state of Idaho Industrial Wastewater Reuse Permit (LA 000161 01, Modification B), for the wastewater land application site at the Idaho National Laboratory Site's Advanced Test Reactor Complex Cold Waste Pond from November 1, 2010 through October 31, 2011. The report contains the following information: Facility and system description Permit required effluent monitoring data and loading rates Groundwater monitoring data Status of compliance activities Noncompliance and other issues Discussion of the facility's environmental impacts During the 2011 permit year, approximately 166 million gallons of wastewater were discharged to the Cold Waste Pond. This is well below the maximum annual permit limit of 375 million gallons. As shown by the groundwater sampling data, sulfate and total dissolved solids concentrations are highest near the Cold Waste Pond and decrease rapidly as the distance from the Cold Waste Pond increases. Although concentrations of sulfate and total dissolved solids are elevated near the Cold Waste Pond, both parameters were below the Ground Water Quality Rule Secondary Constituent Standards in the down gradient monitoring wells.

  2. Seasonal evolution of melt ponds on Arctic sea ice

    NASA Astrophysics Data System (ADS)

    Webster, Melinda A.; Rigor, Ignatius G.; Perovich, Donald K.; Richter-Menge, Jacqueline A.; Polashenski, Christopher M.; Light, Bonnie

    2015-09-01

    The seasonal evolution of melt ponds has been well documented on multiyear and landfast first-year sea ice, but is critically lacking on drifting, first-year sea ice, which is becoming increasingly prevalent in the Arctic. Using 1 m resolution panchromatic satellite imagery paired with airborne and in situ data, we evaluated melt pond evolution for an entire melt season on drifting first-year and multiyear sea ice near the 2011 Applied Physics Laboratory Ice Station (APLIS) site in the Beaufort and Chukchi seas. A new algorithm was developed to classify the imagery into sea ice, thin ice, melt pond, and open water classes on two contrasting ice types: first-year and multiyear sea ice. Surprisingly, melt ponds formed ˜3 weeks earlier on multiyear ice. Both ice types had comparable mean snow depths, but multiyear ice had 0-5 cm deep snow covering ˜37% of its surveyed area, which may have facilitated earlier melt due to its low surface albedo compared to thicker snow. Maximum pond fractions were 53 ± 3% and 38 ± 3% on first-year and multiyear ice, respectively. APLIS pond fractions were compared with those from the Surface Heat Budget of the Arctic Ocean (SHEBA) field campaign. APLIS exhibited earlier melt and double the maximum pond fraction, which was in part due to the greater presence of thin snow and first-year ice at APLIS. These results reveal considerable differences in pond formation between ice types, and underscore the importance of snow depth distributions in the timing and progression of melt pond formation.

  3. Investigation of a Water-Pond Arresting of a Dynamic Model of a Jet Transport

    NASA Technical Reports Server (NTRS)

    Thompson, William C.

    1961-01-01

    Brief dynamic-model tests have been made at the request of the Federal Aviation Agency to investigate the use of a shallow pond of water at the end of a runway as a means of arresting jet-transport aircraft when they are forced to abort on take-off or overrun on landing. Such a scheme is of particular interest for civil aircraft because it requires no modifications or attachments to the airplane and no mechanical devices in the arresting system. A modification of this scheme that uses a flexible plastic cover over the water surface has also been tested. The purpose of this paper is to present the results of a dynamic model investigation which would aid in determining whether the water-pond arresting system could be used as a means of arresting airplane overrun.

  4. Dual Wall Angles Would Enhance Performance Of A Solar Pond

    NASA Technical Reports Server (NTRS)

    Noever, David A.

    1995-01-01

    Proposed dual-angle design for Sun-facing wall of solar pond enhances solar-energy-storage performance of pond; increase in performance over that of similar pond with conventional (single-angle) wall estimated to be 25 percent. Design compromises between maximizing heating and minimizing convection. Top part of Sun-facing wall optimized for top colder layer of water, less tendency toward convective mixing. Bottom part of wall optimized for bottom, warmer layer of water, greater tendency towards convection. Optimization involves consideration of both anticipated temperature-vs.-depth profile (affects tendency toward convection) and latitude (affects angle of incidence of solar radiation and rate of heating).

  5. Evaluation of the Rulison drilling effluent pond as trout habitat

    SciTech Connect

    1998-06-23

    The Rulison Site is located in Section 25, township 7 South, Range 95 West, Garfield County, Colorado. The site is approximately 19 kilometers (km) (12 miles [mi]) southwest of Rifle Colorado, and approximately 65 km (40 mi) northeast of Grand Junction, Colorado. Project Ruhson was an experiment conducted jointly by the U.S. Atomic Energy Commission and Austral Oil Company to test the feasibility of using a nuclear device to increase natural gas production in low permeability geological formations. The experiment was conducted on September 10, 1969, and consisted of detonating a 43-kiloton nuclear device at a depth of 2,568 meters (m) (8,426 feet [ft]) below the ground surface (DOE, 1994). The Rulison Drilling Effluent Pond (called `the pond`) is an engineered structure covering approximately 0.2 hectare (0.5 acre), which was excavated and used to store drilling fluids during drilling of the device emplacement well. The drilling fluids consisted of bentonitic drilling mud with additives such as diesel fuel and chrome lignosulfonate. Most of the drilling muds were removed from the pond when the site was decommissioned in 1976, and the pond was subsequently stocked with rainbow trout by the land owner and used as a fishing pond. In 1994 and 1995, the U.S. Department of Energy (DOE) conducted sampling of the pond to evaluate residual contamination from the drilling fluids. Based on the results of this sampling, the DOE conducted a voluntary cleanup action in order to reduce the levels of total petroleum hydrocarbons and chromium in pond sediments. The cleanup was conducted between August and mid-November of 1995. At the end of cleanup activities, the pond was lined with a clay geofabric and left dry. The geofabric was covered with sod to protect it. The pond has since been refilled by snowmelt and inflow from a spring. Prior to remediation, the pond apparently had sufficient water quality and food resources to support stocked rainbow trout. The purpose of this

  6. Management and conservation of San Francisco Bay salt ponds: Effects of pond salinity, area, tide, and season on pacific flyway waterbirds

    USGS Publications Warehouse

    Warnock, N.; Page, G.W.; Ruhlen, T.D.; Nur, N.; Takekawa, J.Y.; Hanson, J.T.

    2002-01-01

    Throughout the world, coastal salt ponds provide habitat for large numbers and diversities of waterbirds. San Francisco Bay contains the most important coastal salt pond complexes for waterbirds in the United States, supporting more than a million waterbirds through the year. As an initial step in attempting to understand how the anticipated conversion of salt ponds to tidal marsh might affect the Bay's bird populations, the number of birds using salt ponds on high and low tides was counted during the winter months of 1999/00 and 2000/01. Behavior and habitat use of birds in these ponds were assessed, and the effects of tide cycle, pond salinity, and pond area on bird use were examined. We recorded 75 species of waterbirds in surveys of salt ponds in the South Bay from September 1999 to February 2001, totaling over a million bird use days on high tide. Shorebirds and dabbling ducks were the most abundant groups of birds using the salt ponds. Waterbird numbers and diversity were significantly affected by the salinity of ponds in a non-linear fashion with lower numbers and diversity on the highest salinity ponds. With the exception of ducks and Eared Grebe (Podiceps nigricollis), tide height at the Bay significantly affected bird numbers in the salt ponds with ponds at high tides having higher numbers of birds than the same ponds on low tides. Considerable numbers of birds fed in the salt ponds on high and low tides, although this varied greatly by species. Habitat use varied by tide. Management recommendations include maintaining ponds of varying salinities and depths. Restoring salt ponds to tidal marsh should proceed with caution to avoid loss of waterbird diversity and numbers in San Francisco Bay.

  7. Ecosystem Metabolism and Air-Water Fluxes of Greenhouse Gases in High Arctic Wetland Ponds

    NASA Astrophysics Data System (ADS)

    Lehnherr, I.; Venkiteswaran, J.; St. Louis, V. L.; Emmerton, C.; Schiff, S. L.

    2012-12-01

    Freshwater lakes and wetlands can be very productive systems on the Arctic landscape compared to terrestrial tundra ecosystems and provide valuable resources to many organisms, including waterfowl, fish and humans. Rates of ecosystem productivity dictate how much energy flows through food webs, impacting the abundance of higher-level organisms (e.g., fish), as well as the net carbon balance, which determines whether a particular ecosystem is a source or sink of carbon. Climate change is predicted to result in warmer temperatures, increased precipitation and permafrost melting in the Arctic and is already altering northern ecosystems at unprecedented rates; however, it is not known how freshwater systems are responding to these changes. To predict how freshwater systems will respond to complex environmental changes, it is necessary to understand the key processes, such as primary production and ecosystem respiration, that are driving these systems. We sampled wetland ponds (n=8) and lakes (n=2) on northern Ellesmere Island (81° N, Nunavut, Canada) during the open water season for a suite of biogeochemical parameters, including concentrations of dissolved gases (O2, CO2, CH4, N2O) as well as stable-isotope ratios of dissolved inorganic carbon (δ13C-DIC), dissolved oxygen (δ18O-DO), and water (δ18O-H2O). We will present rates of primary production and ecosystem respiration, modeled from the concentration and stable isotope ratios of DIC and DO, as well as air-water gas exchange of greenhouse gases in these high Arctic ponds and lakes. Preliminary results demonstrate that ecosystem metabolism in these ponds was high enough to result in significant deviations in the isotope ratios of DIC and DO from atmospheric equilibrium conditions. In other words ecosystem rates of primary production and respiration were faster than gas exchange even in these small, shallow, well-mixed ponds. Furthermore, primary production was elevated enough at all sites except Lake Hazen, a

  8. A compartmental model to describe hydraulics in a full-scale waste stabilization pond.

    PubMed

    Alvarado, Andres; Vedantam, Sreepriya; Goethals, Peter; Nopens, Ingmar

    2012-02-01

    The advancement of experimental and computational resources has facilitated the use of computational fluid dynamics (CFD) models as a predictive tool for mixing behaviour in full-scale waste stabilization pond systems. However, in view of combining hydraulic behaviour with a biokinetic process model, the computational load is still too high for practical use. This contribution presents a method that uses a validated CFD model with tracer experiments as a platform for the development of a simpler compartmental model (CM) to describe the hydraulics in a full-scale maturation pond (7 ha) of a waste stabilization ponds complex in Cuenca (Ecuador). 3D CFD models were validated with experimental data from pulse tracer experiments, showing a sufficient agreement. Based on the CFD model results, a number of compartments were selected considering the turbulence characteristics of the flow, the residence time distribution (RTD) curves and the dominant velocity component at different pond locations. The arrangement of compartments based on the introduction of recirculation flow rate between adjacent compartments, which in turn is dependent on the turbulence diffusion coefficient, is illustrated. Simulated RTD's from a systemic tanks-in-series (TIS) model and the developed CM were compared. The TIS was unable to capture the measured RTD, whereas the CM predicted convincingly the peaks and lags of the tracer experiment using only a minimal fraction of the computational demand of the CFD model. Finally, a biokinetic model was coupled to both approaches demonstrating the impact an insufficient hydraulic model can have on the outcome of a modelling exercise. TIS and CM showed drastic differences in the output loads implying that the CM approach is to be used when modelling the biological performance of the full-scale system. PMID:22137448

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

    NASA Astrophysics Data System (ADS)

    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.

  10. 56. LOOKING WEST AT CONCRETE TUNNEL DIVERING LOG POND OUTFLOW ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    56. LOOKING WEST AT CONCRETE TUNNEL DIVERING LOG POND OUTFLOW AWAY FROM SAWMILL SUPPORTS. PHOTOGRAPHER: UNKNOWN. DATE: 1954. COURTESY OF RALPH HULL. - Hull-Oakes Lumber Company, 23837 Dawson Road, Monroe, Benton County, OR

  11. Using Stormwater Detention Ponds for Aquatic Science Instruction.

    ERIC Educational Resources Information Center

    Cahoon, Lawrence B.

    1996-01-01

    Describes the use of recently constructed stormwater detention ponds to conduct a set of field and laboratory exercises in an undergraduate limnology course. Provides a number of logistical advantages that can benefit those teaching aquatic sciences. (JRH)

  12. 53. View of Wings Rest Pond with reflection of "grandpappy" ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    53. View of Wings Rest Pond with reflection of "grandpappy" looking from the southwest (similar to HALS no. LA-1-23) - Briarwood: The Caroline Dormon Nature Preserve, 216 Caroline Dormon Road, Saline, Bienville Parish, LA

  13. 54. View of footbridge from Wings Rest Pond looking from ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    54. View of footbridge from Wings Rest Pond looking from the east (similar to HALS no. LA-1-24) - Briarwood: The Caroline Dormon Nature Preserve, 216 Caroline Dormon Road, Saline, Bienville Parish, LA

  14. 52. View of "grandpappy" tree with Wings Rest Pond in ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    52. View of "grandpappy" tree with Wings Rest Pond in background looking from the northeast (similar to HALS no. LA-1-22) - Briarwood: The Caroline Dormon Nature Preserve, 216 Caroline Dormon Road, Saline, Bienville Parish, LA

  15. 4. NORTH END OF TANKS SHOWING CONCRETE RETENTION POND WITH ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. NORTH END OF TANKS SHOWING CONCRETE RETENTION POND WITH BUTYL LINER; VIEW TO EAST. - Cape Canaveral Air Station, Launch Complex 17, Facility 28406, East end of Lighthouse Road, Cape Canaveral, Brevard County, FL

  16. GENERAL VIEW OF THE SETTLINGDIVERSION POND, THE TUMALO RESERVIOR FEED ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    GENERAL VIEW OF THE SETTLING-DIVERSION POND, THE TUMALO RESERVIOR FEED CANAL INTAKE STRUCTURE, AND ADJACENT BRIDGE. LOOKING SOUTH - Tumalo Irrigation District, Tumalo Project, West of Deschutes River, Tumalo, Deschutes County, OR

  17. VIEW OF TWIN COLUMBIA SOUTHERN CANAL INTAKE STRUCTURES (POND SIDE), ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    VIEW OF TWIN COLUMBIA SOUTHERN CANAL INTAKE STRUCTURES (POND SIDE), TUMALO RESERVOIR FEED CANAL INTAKE STRUCTURE TO LEFT. LOOKING NORTH/NORTHEAST - Tumalo Irrigation District, Tumalo Project, West of Deschutes River, Tumalo, Deschutes County, OR

  18. Beyond Historical Fiction: Speare's "The Witch of Blackbird Pond."

    ERIC Educational Resources Information Center

    Thuente, Mary Helen

    1985-01-01

    Reviews "The Witch of Blackbird Pond" by E. Speare to show how the full narrative power of the novel derives from the author's successful integration of two separate narrative genres: historical fiction and the folktale. (EL)

  19. ALGAL METABOLITE INFLUENCE ON BLOOM SEQUENCE IN EUTROPHIED FRESHWATER PONDS

    EPA Science Inventory

    The extracellular metabolites of planktonic bloom dominant algae play a most significant role in the determination of bloom sequence in a eutrophied freshwater pond. Certain extracellular metabolites of planktonic blue-green algae substantially inhibit the growth of planktonic di...

  20. MALLARD REPRODUCTIVE TESTING IN A POND ENVIRONMENT: A PRELIMINARY STUDY

    EPA Science Inventory

    A 2-year preliminary study was conducted on mallard ducks to determine the feasibility of using outdoor pond enclosures for reproductive studies and to evaluate the effects of the insecticide chlorpyrifos on mallard reproduction. No significant reproductive effects were observed ...

  1. 2. VIEW OF POND B, LOOKING NORTHEAST FROM THE WEST ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. VIEW OF POND B, LOOKING NORTHEAST FROM THE WEST SIDE OF THE SOURIS RIVER VALLEY, DUE SOUTH OF THE LOOKOUT TOWER - Upper Souris National Wildlife Refuge Dams, Souris River Basin, Foxholm, Surrey (England), ND

  2. 10. VIEW OF THE SEDIMENT DAM AND POND, FACING SOUTH. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    10. VIEW OF THE SEDIMENT DAM AND POND, FACING SOUTH. PHOTO TAKEN FROM WATER PUMP (FEATURE B-25). - Nevada Lucky Tiger Mill & Mine, East slope of Buckskin Mountain, Paradise Valley, Humboldt County, NV

  3. Level 1 remedial investigation work plan, 300 Area Process Ponds

    SciTech Connect

    Not Available

    1987-06-01

    This report discusses the objectives of the site characterization for the 300 Area Process Ponds which are to identify and quantify contamination at the ponds and to estimate their potential impact on human health and the environment. The results of the site characterization will be used to identify any future actions related to contamination at the site and to identify any additional data requirements needed to support selection of a remedial action. 9 refs., 12 figs., 8 tabs.

  4. Observations of the transmittance in two solar ponds

    SciTech Connect

    Almanza, R.; Bryant, M.C.

    1983-11-01

    A NaCl salt gradient solar pond has been in continuous operation at the University of New Mexico since the fall of 1975; a smaller pond, using KNO/sub 3/ to produce the salinity gradient, was commissioned in the fall of 1981. The distribution of absorbed radiation in the ponds is of key importance in the determination of their efficiencies for collecting and storing solar energy. The absorption coefficient of light in an aqueous solution is very dependent upon wavelength; the spectral distribution of sunlight shifts toward the blue and the amount of solar energy absorbed per unit length of path declines with depth of penetration. The presence of suspended solids and bioforms further complicate the transmittance of sun light through the pond, specially since this contamination tends to vary strongly with depth. Because of its importance to the phytoplankton population , considerable work has been done by oceanographers on the absorption and scattering of light for different wavelengths. However, in a solar pond the big question is the amount of energy reaching the lower convective layer (storage). Several attempts have been made to measure the transmittance in solar ponds, mainly NaCl but the problem is to find a temperature-insensitive submersible pyranometer. Convenient formulas have been offered for the attenuation of solar radiation in pond water by considering it to be divided into spectral bands, or by fitting simple analytical functions, or specifying the extintion coefficient. (For the first method, it is necessary to know the absorption and scattering of light for different lambda.) In this paper some measurements of transmittance in the UNM ponds, are presented thereby exhibiting a simple procedure which may be of interest to others in this field.

  5. Formation of the "ponds" on asteroid (433) Eros by fluidization

    NASA Astrophysics Data System (ADS)

    Sears, D. W. G.; Tornabene, L. L.; Osinski, G. R.; Hughes, S. S.; Heldmann, J. L.

    2015-11-01

    The "ponds" on asteroid (433) Eros are fine-grained deposits approximating flat (quasi-equipotential) surfaces with respect to local topographic depressions (e.g., craters) in spacecraft images. These ponds are discussed in the context of laboratory simulation experiments, crater-related ponded and pitted deposits observed on Mars and Vesta, terrestrial phreatic craters, and degassing features associated with eroded impact craters on Earth. While the details of formation of these features on Mars, Vesta and the Earth are thought to be different, they all include mechanisms that require the interactions between surface materials and volatiles (e.g., water vapor). Indeed, analogous features similar to the Eros ponds can be reproduced in the laboratory by the release of vapor (ice sublimation, water evaporation, or N2) through an unconsolidated regolith (independent of regolith composition). Eros is widely thought to be dry, but the discovery of exogenic water on Vesta, and recent arguments that subsurface water might be present in the inner asteroid belt suggest that endogenic water might also be present and serve as a source of the gases produced in the ponds. The amount of water required is comparable to the amount of water observed in little-metamorphosed ordinary chondrites (a few wt%). The primary morphologic characteristics of the Eros ponds can be explained in this model. The heat source for degassing could have been solar heating following transfer from a main belt orbit to a near Earth orbit. Although other hypotheses (e.g., electrostatic levitation, seismic shaking, and comminution of boulders) can account for most of the features of the ponds, recent observations regarding the role of volatiles on planetary surfaces, our laboratory experiments, and fluidization deposits on active comets suggests that degassing is a reasonable hypothesis to be considered and further tested for explaining the Eros ponds, and similar features on other bodies.

  6. Highway runoff and potential for removal of heavy metals in an infiltration pond in Portugal

    PubMed

    Barbosa; Hvitved-Jacobsen

    1999-09-01

    Highway runoff from IP 4, a mountain road in the north-east of Portugal, has been monitored using a system integrating a raingauge, a flowmeter and an automatic water sampler. Average daily traffic (ADT) is 6000 and the study catchment has 5970 m2 of total area and 2500 m2 of road pavement. A single stormwater outlet discharges into an infiltration pond with overflow to a creek. Sampling was carried out before the runoff water entered the pond. Among the parameters analysed in the runoff water, the heavy metals cadmium (Cd), chromium (Cr), copper (Cu), lead (Pb) and zinc (Zn) were emphasised because of their toxicity. Concentrations of Cd and Cr were usually lower than the detection limit (1 microgram/l). Copper levels found were between 1 and 54 micrograms/l; lead from 1 to 200 micrograms/l and zinc from 50 to 1460 micrograms/l. A first flush effect was observed, meaning that the first 50% of the runoff volume for each event typically transported between 61 and 69% of the total suspended solids, Zn, Cu and Pb loads. Runoff water is totally infiltrated into the pond and heavy metals are being sorbed to the soil. Soils used in infiltration ponds should have specific characteristics in order to perform effectively and ensure groundwater protection. Not only well-known soil texture and composition characteristics are relevant: the soil sorption capacity--the extension and reversibility of the processes--is of main importance in this kind of highway runoff treatment. Experiments concerning the sorption of Zn, Cu and Pb to soils, followed by desorption at pH values of 2, 4 and 6 were conducted in the laboratory. These experiments were performed with the soil existing at the highway IP 4 infiltration pond and with two other common types of Portuguese soils. The three types of soil showed different behaviours, which must be related to their characteristics; the soil pH seemed to play a significant role in controlling the Zn, Cu and Pb sorption processes. As expected, as

  7. Improving microalgal growth with small bubbles in a raceway pond with swing gas aerators.

    PubMed

    Yang, Zongbo; Cheng, Jun; Liu, Jianzhong; Zhou, Junhu; Cen, Kefa

    2016-09-01

    A novel swing gas aerator was developed to generate small bubbles for improving the mass transfer coefficient and microalgal growth rate in a raceway pond. A high-speed photography system (HSP) was used to measure the bubble diameter and generation time, and online precise dissolved oxygen probes and pH probes were used to measure the mass transfer coefficient and mixing time. Bubble generation time and diameter decreased by 21% and 9%, respectively, when rubber gas aerators were swung in the microalgae solution. When water pump power and gas aeration rate increased in a raceway pond with swing gas aerators and oscillating baffles (SGAOB), bubble generation time and diameter decreased but solution velocity and mass transfer coefficient increased. The mass transfer coefficient increased by 25% and the solution velocity increased by 11% when SGAOB was used, and the microalgal biomass yield increased by 18%. PMID:27243604

  8. Mutagenic potential of water concentrates from the effluent of a waste oil storage pond

    SciTech Connect

    Brown, K.W.; Donnelly, K.C.

    1982-04-01

    An investigation to compare the mutagenic effects of water samples collected before and after a contaminated waste oil storage pond was dredged and to evaluate the utility of bioassays for the determination of the mutagenic potential of a complex mixture is presented. Water samples collected from the pond were analyzed in two biological systems capable of detecting mutagens and potential carcinogens (Salmonella/microsome assay and Bacillus subtillis DNA repair assay). Although the water samples contained compounds which were toxic to bacteria, the sample collected after the dredging operation exhibited a substantial reduction in its capacity to produce repairable DNA damage. The results indicate the potential utility of bioassays for the detection of mutagens in environmental samples. (JMT)

  9. Chemical fractionation of Cu and Zn in stormwater, roadway dust and stormwater pond sediments

    USGS Publications Warehouse

    Camponelli, Kimberly M.; Lev, Steven M.; Snodgrass, Joel W.; Landa, Edward R.; Casey, Ryan E.

    2010-01-01

    This study evaluated the chemical fractionation of Cu and Zn from source to deposition in a stormwater system. Cu and Zn concentrations and chemical fractionation were determined for roadway dust, roadway runoff and pond sediments. Stormwater Cu and Zn concentrations were used to generate cumulative frequency distributions to characterize potential exposure to pond-dwelling organisms. Dissolved stormwater Zn exceeded USEPA acute and chronic water quality criteria in approximately 20% of storm samples and 20% of the storm duration sampled. Dissolved Cu exceeded the previously published chronic criterion in 75% of storm samples and duration and exceeded the acute criterion in 45% of samples and duration. The majority of sediment Cu (92–98%) occurred in the most recalcitrant phase, suggesting low bioavailability; Zn was substantially more available (39–62% recalcitrant). Most sediment concentrations for Cu and Zn exceeded published threshold effect concentrations and Zn often exceeded probable effect concentrations in surface sediments.

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

    SciTech Connect

    Hudson, D.B.; Guertal, W.R.; Flint, A.L.

    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.

  11. Acidification as environmental pollution: effects on fish-pond ecology

    SciTech Connect

    Murad, H.A.

    1987-01-01

    To establish the impact of acidity on fish production in ponds, experiments were conducted in fertilized sunfish (Lepomis spp.) ponds and fed channel catfish (Ictalurus punctatus) ponds. The alkalinity and pH of pond water were lowered by additions of H/sub 2/SO/sub 4/. Total alkalinity levels were 1, 3, 6, 8, and 20 mg/liter in sunfish ponds and 0, 5, and 20 in catfish production ponds. Water quality and phytoplankton density were monitored. The decrease in alkalinity caused changes in fish production and phytoplankton communities. Production of sunfish decreased with decreasing alkalinity below 20 mg/liter. Channel catfish yields were not affected significantly at a total alkalinity of 5 mg/liter and above (P > 0.05). No sign of fish stress of aluminum accumulation in the tissue were detected in catfish. There was no relation between alkalinity level and off-flavor in catfish. Chlorophyll a concentration increased as alkalinity and pH decreased, although total number of phytoplankters, gross photosynthesis, and turbidity decreased with decreases in total alkalinity. Phosphorus was more available at low alkalinity levels. Total hardness increased as alkalinity decreased.

  12. Characterization of methane flux from photosynthetic oxidation ponds in a wastewater treatment plant.

    PubMed

    Detweiler, Angela M; Bebout, Brad M; Frisbee, Adrienne E; Kelley, Cheryl A; Chanton, Jeffrey P; Prufert-Bebout, Leslie E

    2014-01-01

    Photosynthetic oxidation ponds are a low-cost method for secondary treatment of wastewater using natural and more energy-efficient aeration strategies. Methane (CH(4)) is produced during the anaerobic digestion of organic matter, but only some of it is oxidized in the water column, with the remaining CH(4) escaping into the atmosphere. In order to characterize the CH(4) flux in two photosynthetic oxidation ponds in a wastewater treatment plant in northern California, the isotopic compositions and concentrations of CH(4) were measured in the water column, in bubbles and in flux chambers, over a period of 12 to 21 months to account for seasonal trends in CH(4) emissions. Methane flux varied seasonally throughout the year, with an annual average flux of 5.5 g CH(4) m⁻² d⁻¹ Over half of the CH(4) flux, 56.1-74.4% v/v, was attributed to ebullition. The oxidation efficiency of this system was estimated at 69.1%, based on stable carbon isotopes and a calculated fractionation factor of 1.028. This is the first time, to our knowledge, that a fractionation factor for CH(4) oxidation has been empirically determined for oxidation ponds. Quantifying CH(4) emissions from these systems is essential to properly identify their contribution and to mitigate their impact on global warming. PMID:25259485

  13. Baseline study of methane emission from anaerobic ponds of palm oil mill effluent treatment.

    PubMed

    Yacob, Shahrakbah; Ali Hassan, Mohd; Shirai, Yoshihito; Wakisaka, Minato; Subash, Sunderaj

    2006-07-31

    The world currently obtains its energy from the fossil fuels such as oil, natural gas and coal. However, the international crisis in the Middle East, rapid depletion of fossil fuel reserves as well as climate change have driven the world towards renewable energy sources which are abundant, untapped and environmentally friendly. Malaysia has abundant biomass resources generated from the agricultural industry particularly the large commodity, palm oil. This paper will focus on palm oil mill effluent (POME) as the source of renewable energy from the generation of methane and establish the current methane emission from the anaerobic treatment facility. The emission was measured from two anaerobic ponds in Felda Serting Palm Oil Mill for 52 weeks. The results showed that the methane content was between 35.0% and 70.0% and biogas flow rate ranged between 0.5 and 2.4 L/min/m(2). Total methane emission per anaerobic pond was 1043.1 kg/day. The total methane emission calculated from the two equations derived from relationships between methane emission and total carbon removal and POME discharged were comparable with field measurement. This study also revealed that anaerobic pond system is more efficient than open digesting tank system for POME treatment. Two main factors affecting the methane emission were mill activities and oil palm seasonal cropping. PMID:16125215

  14. Emerging contaminant degradation and removal in algal wastewater treatment ponds: Identifying the research gaps.

    PubMed

    Norvill, Zane N; Shilton, Andy; Guieysse, Benoit

    2016-08-01

    Whereas the fate of emerging contaminants (ECs) during 'conventional' and 'advanced' wastewater treatment (WWT) has been intensively studied, little research has been conducted on the algal WWT ponds commonly used in provincial areas. The long retention times and large surface areas exposed to light potentially allow more opportunities for EC removal to occur, but experimental evidence is lacking to enable definite predictions about EC fate across different algal WWT systems. This study reviews the mechanisms of EC hydrolysis, sorption, biodegradation, and photodegradation, applying available knowledge to the case of algal WWT. From this basis the review identifies three main areas that need more research due to the unique environmental and ecological conditions occurring in algal WWT ponds: i) the effect of diurnally fluctuating pH and dissolved oxygen upon removal mechanisms; ii) the influence of algae and algal biomass on biodegradation and sorption under relevant conditions; and iii) the significance of EC photodegradation in the presence of dissolved and suspended materials. Because of the high concentration of dissolved organics typically found in algal WWT ponds, most EC photodegradation likely occurs via indirect mechanisms rather than direct photolysis in these systems. PMID:27135171

  15. Metagenomic sequence of prokaryotic microbiota from an intermediate-salinity pond of a saltern in isla cristina, Spain.

    PubMed

    Fernández, Ana B; León, María José; Vera, Blanca; Sánchez-Porro, Cristina; Ventosa, Antonio

    2014-01-01

    Marine salterns are artificial multipond systems designed for the commercial production of salt by evaporation of seawater. We report here the metagenomic sequence of the prokaryotic microbiota of a pond with intermediate salinity (21% total salts) of a saltern located in Isla Cristina, Huelva, southwest Spain. PMID:24526635

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

    SciTech Connect

    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.

  17. Diurnal hydrochemical variations in a karst spring and two ponds, Maolan Karst Experimental Site, China: Biological pump effects

    NASA Astrophysics Data System (ADS)

    Liu, Huan; Liu, Zaihua; Macpherson, G. L.; Yang, Rui; Chen, Bo; Sun, Hailong

    2015-03-01

    A karst spring and two downstream ponds fed by the spring at the Maolan Karst Experimental Site, Guizhou Province, China, were used to investigate the effect of submerged plants on the CO2-H2O-CaCO3 system during a time of spring base flow in summer when underwater photosynthesis was strongest. Temperature, pH, electrical conductivity (EC) and dissolved oxygen (DO) were recorded at 15 min intervals for a period of 30 h (12:00 29 August-18:00 30 August, 2012). [Ca2+], [HCO3-], CO2 partial pressure (pCO2) and saturation index of calcite (SIC) were estimated from the high-frequency measurements. Water samples were also collected three times a day (early morning, midday and evening) for δ13CDIC determination. A floating CO2-flux monitoring chamber was used to measure CO2 flux at the three locations. Results show that there was little or no diurnal variation in the spring water parameters. In the midstream pond with flourishing submerged plants, however, all parameters show distinct diurnal changes: temperature, pH, DO, SIc, δ13CDIC increased during the day and decreased at night, while EC, [HCO3-], [Ca2+], and pCO2 behaved in the opposite sense. In addition, maximum DO values (16-23 mg/L) in the midstream pond at daytime were two to three times those of water equilibrated with atmospheric O2, indicating strong aquatic photosynthesis. The proposed photosynthesis is corroborated by the low calculated pCO2 of 20-200 ppmv, which is much less than atmospheric pCO2. In the downstream pond with fewer submerged plants but larger volume, all parameters displayed similar trends to the midstream pond but with much less change, a pattern that we attribute to the lower biomass/water volume ratio. The diurnal hydrobiogeochemical variations in the two ponds depended essentially on illumination, indicating that photosynthesis and respiration by the submerged plants are the dominant controlling processes. The large loss of DIC between the spring and midstream pond, attributed to

  18. Actinide behavior in a freshwater pond

    SciTech Connect

    Trabalka, J.R.; Bogle, M.A.; Scott, T.G.

    1983-01-01

    Long-term investigations of solution chemistry in an alkaline freshwater pond have revealed that actinide oxidation state behavior, particularly that of plutonium, is complex. The Pu(V,VI) fraction was predominant in solution, but it varied over the entire range reported from other natural aquatic environments, in this case, as a result of intrinsic biological and chemical cycles (redox and pH-dependent phenomena). A strong positive correlation between plutonium (Pu), but not uranium (U), and hydroxyl ion over the observation period, especially when both were known to be in higher oxidation states, was particularly notable. Coupled with other examples of divergent U and Pu behavior, this result suggests that Pu(V), or perhaps a mixture of Pu(V,VI), was the prevalent oxidation state in solution. Observations of trivalent actinide sorption behavior during an algal bloom, coupled with the association with a high-molecular weight (nominally 6000 to 10,000 mol wt) organic fraction in solution, indicate that solution-detritus cycling of organic carbon, in turn, may be the primary mechanism in amercium-curium (Am-Cm) cycling. Sorption by sedimentary materials appears to predominate over other factors controlling effective actinide solubility and may explain, at least partially, the absence of an expected strong positive correlation between carbonate and dissolved U. 49 references, 6 figures, 12 tables.

  19. Compost treatment of contaminated pond sediment

    SciTech Connect

    Francis, M.; Gukert, D. |

    1995-12-31

    This paper summarizes an experiment involving compost treatment of pond sediment contaminated with hydrocarbons. Experimental variables included the size, shape, and aeration of the compost pile. Pile temperature measurements and hydrocarbon analyses were made periodically. Temperatures in the pyramid shaped compost piles rose quickly and remained elevated above ambient for about one month; during this period, hydrocarbon loss from the piles was greatest. The flat pile did not show elevated temperatures at any time, and total hydrocarbon losses by volatilization were 19.1 g. Total losses from the passively aerated pile were 1.02 g, while the actively aerated pile had losses of 0.08 g. Individual identified component compounds in the sediment included polycyclic aromatic hydrocarbons (PAHs). Final levels were in the 2 to 20 ppM range compared to 100 to 400 ppM in the original sediment. Composting removed PAH components and other light organics, and the composted material can be stored onsite or landfilled without leaching concerns.

  20. Direct Experimental Assessment of Microbial Activity in North Pond Sediments

    NASA Astrophysics Data System (ADS)

    Ferdelman, T. G.; Picard, A.; Morando, M.; Ziebis, W.

    2009-12-01

    North Pond, an isolated sediment pond located at 22°45’N on the western flank of the Mid-Atlantic Ridge, offered the opportunity to study microbial activities in deeply-buried low-activity sediments. About 8 x 15 km in size with sediment maximum thickness of about 300 m, North Pond is completely surrounded by exposed 7 Ma old basement. North Pond lies above the carbonate compensation depth at a water depth about 4500 m; hydrostatic pressure at the seafloor is about 45 MPa and the temperature is near 2°C. During the a R/V MS Merian cruise (MSM-11/1) in February -March 2009, 14 gravity cores of up to 9 m length were successfully obtained, from which samples were taken with 1-m resolution for experimental activity measurements. The goal of the experimental work was 1) to examine potential metabolic pathways in North Pond sediments and carbon assimilation pathways in this low-energy environment, and 2) explore the effects of pressure on microbial metabolic activities. As dissolved oxygen penetrated through all depths, sediments were aerobically sampled, processed and incubated at 4°C. Selected samples were immediately stored at in situ pressure until further use. The microbial uptake of both organic and inorganic carbon in selected North Pond sediment samples was investigated by following the fate of 14C in radio-labeled organic and organic compounds in North Pond sediment slurry incubations. Shipboard and on-shore experiments using 14C-leucine, 14C-glucose and 14C-bicarbonate were performed on selected cores. Day- to month- incubations were performed at 4°C. Parallel incubations were conducted at atmospheric pressure (0.1 MPa) and in situ pressure (~45 MPa). Either whole cell extraction (Kallmeyer et al., Limnol. Oceanogr.: Methods 6, 2008, 238-245) or protein-DNA extraction was carried on after various incubations to determine the fraction of 14C incorporated into cellular components. Formation of 14C-labeled CO2 was determined on samples incubated with 14C

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

    USGS Publications Warehouse

    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.

  2. Seepage and Ponding within a Southern Hemisphere Crater

    NASA Technical Reports Server (NTRS)

    1998-01-01

    Mars Orbiter Camera (MOC) image 7707 (subframe) reproduced at full resolution, about 24.5 meters/pixel (80.4 feet/pixel). Picture shows an area approximately 25.1 x 31.3 km (15.6 x 19.5 miles) in size. Sun illumination is from the lower left. The MOC image is centered near 65.1oS latitude, 15.1oW longitude. Image was obtained during the Southern Spring season on December 29, 1997, at 1:19 p.m. PST on Mars Global Surveyor's 77th orbit around Mars.

    Despite evidence of catastrophic floods and integrated valley networks on Mars, unequivocal evidence of ponding has been difficult, if not impossible, to find. MOC image 7707 shows what, at first examination, appears to be such evidence. There are two striking geomorphic attributes of the crater shown in the image: (1) The crater wall shows channeling suggestive of fluid seepage; and (2) The contact (i.e., the boundary between two types of geologic materials) between the dark floor materials and the lighter materials of the crater wall suggests, by the formation of bays and peninsulas, a ponding relationship.

    These relationships are best and most easily explained if, at some time in the past, water seeped out of layers within the crater wall and flowed down into the crater, flooding part of the crater floor. In this interpretation, the dark material may be sediment transported by the seeping water. The appearance of dunes within the crater may be coincidental, or the sand may have been generated by wind and wave action. The lack of superimposed fresh impact craters suggests this process may have been active relatively recently.

    It is important to note that both the channel and floor relationships seen in this image may be formed by other processes, and that there is also the possibility that they may not be related (i.e., that the fluid from the channels did not emplace the dark, ponded floor material). It is also important to remember that a fluid other than water, for example, fluid lava, could be responsible

  3. Changing the Rules on Fuel Export at Sellafield's First Fuel Storage Pond - 12065

    SciTech Connect

    Carlisle, Derek

    2012-07-01

    The Pile Fuel Storage Pond (PFSP) was built in 1949/50 to receive, store and de-can fuel and isotopes from the Windscale Piles. Following closure of the Piles in 1957, plant operations were scaled down until fuel processing eventually ceased in 1962. The facility has held an inventory of metal fuel both from the Piles and from other programmes since that time. The pond is currently undergoing remediation and removal of the fuel is a key step in that process, unfortunately the fuel export infrastructure on the plant is no longer functional and due to the size and limited lifting capability, the plant is not compatible with today's large volume heavy export flasks. The baseline scheme for the plant is to package fuel into a small capacity flask and transfer it to another facility for treatment and repackaging into a flask compatible with other facilities on site. Due to programme priorities the repackaging facility is not available to do this work for several years causing a delay to the work. In an effort accelerate the programme the Metal Fuel Pilot Project (MFPP) was initiated to challenge the norms for fuel transfer and develop a new methodology for transferring the fuel. In developing a transfer scheme the team had to overcome challenges associated with unknown fuel condition, transfers outside of bulk containment, pyro-phoricity and oxidisation hazards as well as developing remote control and recovery systems for equipment not designed for this purpose. A combination of novel engineering and enhanced operational controls were developed which resulted in the successful export of the first fuel to leave the Pile Fuel Storage Pond in over 40 years. The learning from the pilot project is now being considered by the main project team to see how the new methodology can be applied to the full inventory of the pond. (author)

  4. A coupled biogeochemical-Dynamic Energy Budget model as a tool for managing fish production ponds.

    PubMed

    Serpa, Dalila; Pousão-Ferreira, Pedro; Caetano, Miguel; Cancela da Fonseca, Luís; Dinis, Maria Teresa; Duarte, Pedro

    2013-10-01

    The sustainability of semi-intensive aquaculture relies on management practices that simultaneously improve production efficiency and minimize the environmental impacts of this activity. The purpose of the present work was to develop a mathematical model that reproduced the dynamics of a semi-intensive fish earth pond, to simulate different management scenarios for optimizing fish production. The modeling approach consisted of coupling a biogeochemical model that simulated the dynamics of the elements that are more likely to affect fish production and cause undesirable environmental impacts (nitrogen, phosphorus and oxygen) to a fish growth model based on the Dynamic Energy Budget approach. The biogeochemical sub-model successfully simulated most water column and sediment variables. A good model fit was also found between predicted and observed white seabream (Diplodus sargus) growth data over a production cycle. In order to optimize fish production, different management scenarios were analysed with the model (e.g. increase stocking densities, decrease/increase water exchange rates, decrease/increase feeding rates, decrease phosphorus content in fish feeds, increase food assimilation efficiency and decrease pellets sinking velocity) to test their effects on the pond environment as well as on fish yields and effluent nutrient discharges. Scenarios were quantitatively evaluated and compared using the Analytical Hierarchical Process (AHP) methodology. The best management options that allow the maximization of fish production while maintaining a good pond environment and minimum impacts on the adjacent coastal system were to double standard stocking densities and to improve food assimilation efficiency. PMID:23872182

  5. Thermomagnetic properties of peat-soil layers from Sag pond near Lembang Fault, West Java, Indonesia

    NASA Astrophysics Data System (ADS)

    Iryanti, Mimin; Wibowo, Dimas Maulana; Bijaksana, Satria

    2015-09-01

    Sag pond is a body of water near fault system as water flows blocked by the fault. Sag pond is a special type of environment for peat formation as peat layers in were deposited as the fault moves in episodic fashion. Depending on the history of the fault, peat layers are often interrupted by soil layers. In this study, core of peat-soil layers from a Sag pond in Karyawangi Village near Lembang Fault was obtained and analyzed for its magnetic properties. The 5 m core was obtained using a hand auger. Individual samples were obtained every cm and measured for their magnetic susceptibility. In general, there are three distinct magnetic susceptibility layers that were associated with peat and soil layers. The upper first 1 m is unconsolidated mud layer with its relatively high magnetic susceptibility. Between 1-2.81 m, there is consolidated mud layer and the lowest part (2.82-5) m is basically peat layer. Six samples were then measured for their thermomagnetic properties by measuring their susceptibility during heating and cooling from room temperature to 700°C. The thermomagnetic profiles provide Curie temperatures for various magnetic minerals in the cores. It was found that the upper part (unconsolidated mud) contains predominantly iron-oxides, such as magnetite while the lowest part (peat layer) contains significant amount of iron-sulphides, presumably greigite.

  6. Gull contributions of phosphorus and nitrogen to a Cape Cod kettle pond

    USGS Publications Warehouse

    Portnoy, J.W.; Soukup, M.A.

    1990-01-01

    Nutrient excretion rates and the annual contribution of P from the feces of the gulls Larus argentatus and L. marinus (and of N from L. argentatus) to the nutrient budget of Gull Pond (Wellfleet), a soft water seepage lake, have been estimated. Intensive year-round gull counts by species were combined with determinations of defecation rate and the nutrient content of feces to quantitatively assess the P loading rates associated with regular gull use of this coastal pond on a seasonal and annual basis. Total P loading from gulls was estimated to be 52 kg yr?1, with 17 kg from L. argentatus and 35 kg from L. marinus, resulting from about 5.0 ? 106 h yr?1 and 1.7 ? 106 h yr?1 of pond use. This compares with P loading estimates of 67 kg yr?1 from upgradient septic systems, 2 kg yr?1 from precipitation and 3 kg yr?1 from unpolluted ground water. Fifty-six percent of annual gull P loading was associated with migratory activity in late fall. Estimated annual N loading by L. argentatus was 14 kg TKN, 206 g NO3-N, and 1.85 g g NH3-N.

  7. Evaluation of relocation of unionid mussels into artificial ponds

    USGS Publications Warehouse

    Newton, T.J.; Monroe, E.M.; Kenyon, R.; Gutreuter, S.; Welke, K.I.; Thiel, P.A.

    2001-01-01

    Relocation of unionid mussels into refuges (e.g., hatchery ponds) has been suggested as a management tool to protect these animals from the threat of zebra mussel (Dreissena polymorpha) invasion. To evaluate the efficacy of relocation, we experimentally relocated 768 mussels, representing 5 species (Leptodea fragilis, Obliquaria reflexa, Fusconaia flava, Amblema plicata, and Quadrula quadrula) into an earthen pond at a National Fish Hatchery or back into the river. In both locations, mussels were placed into 1 of 4 treatments (mesh bags, corrals, and buried or suspended substrate-filled trays). Mussels were examined annually for survival, growth (shell length and wet mass), and physiological condition (glycogen concentration in foot and mantle and tissue condition index) for 36 mo in the pond or 40 mo in the river. We observed significant differences in mortality rates between locations (mortality was 4 times greater in the pond than in the river), among treatments (lowest mortality in the suspended trays), and among species (lower mortality in the amblemines than lamp-silines). Overall survival in both locations averaged 80% the 1st year; survival in the pond decreased dramatically after that. Although length and weight varied between locations and over time, these changes were small, suggesting that their utility as short-term measures of well being in long-lived unionids is questionable. Mussels relocated to the pond were in poor physiological condition relative to those in the river, but the magnitude of these differences was small compared to the inherent variability in physiological condition of reference mussels. These data suggest that relocation of unionids into artificial ponds is a high-risk conservation strategy; alternatives such as introduction of infected host fish, identification of mussel beds at greatest risk from zebra mussels, and a critical, large-scale assessment of the factors contributing to their decline should be explored.

  8. Toxicity of ammonia to algae in sewage oxidation ponds.

    PubMed Central

    Abeliovich, A; Azov, Y

    1976-01-01

    Ammonia, at concentrations over 2.0 mM and at pH values over 8.0, inhibits photosynthesis and growth of Scenedesmus obliquus, a dominant species in high-rate sewage oxidation ponds. Photosynthesis of Chlorella pyrenoidosa, Anacystis nidulans, and Plectonema boryanum is also susceptible to ammonia inhibition. Dark respiration and cell morphology were unaffected by any combination of pH and ammonia concentrations tested, thus limiting the apparent effect to inhibition of the normal function of the chloroplasts. Methylamine had the same effect as ammonia, and its penetration into the cells was found to be pH dependent. Therefore, the dependence of toxicity of amines to algae on pH apparently results from the inability to penetrate the cell membrane in the ionized form. When operated at 120-h detention time of raw wastewater, the high-rate oxidation pond maintained a steady state with respect to algal growth and oxygen concentration, and the concentration of ammonia did not exceed 1.0 mM. Shifting the pond to 48-h detention time caused an increase in ammonia concentration in the pond water to 2.5 mM, and the pond gradually turned anaerobic. Photosynthesis, which usually elevates the pH of the pond water to 9.0 to 10.0, could not proceed beyond pH 7.9 because of the high concentration of ammonia, and the algal population was washed out and reduced to a concentration that could maintain a doubling time of 48 h without photosynthesis bringing the pH to inhibitory levels. Under these conditions, the pH of the bond becomes a factor that limits the operational efficiency of the oxidation pond. PMID:7192

  9. Par Pond vegetation status Summer 1995 -- June survey descriptive summary

    SciTech Connect

    Mackey, H.E. Jr.; Riley, R.S.

    1995-06-01

    The water level of Par Pond was lowered approximately 20 feet in mid-1991 in order to protect downstream residents from possible dam failure suggested by subsidence on the downstream slope of the dam and to repair the dam. This lowering exposed both emergent and nonemergent macrophyte beds to drying conditions resulting in extensive losses. A survey of the shoreline aquatic plant communities in June 1995, three months after the refilling of Par Pond to approximately 200 feet above mean sea level, indicated that much of the original plant communities and the intermediate shoreline communities present on the exposed sediments have been lost. The extensive old-field and emergent marsh communities that were present on the exposed shoreline during the drawdown have been flooded and much of the pre-drawdown Par Pond aquatic plant communities have not had sufficient time for re-establishment. The shoreline does, however, have extensive beds of maidencane which extend from the shoreline margin to areas as deep as 2 and perhaps 3 meters. Scattered individual plants of lotus and watershield are common and may indicate likely directions of future wetland development in Par Pond. In addition, within isolated coves, which apparently received ground water seepage and/or stream surface flows during the period of the Par Pond draw down, extensive beds of waterlilies and spike rush are common. Invasion of willow and red maple occurred along the lake shoreline as well. Although not absent from this survey, evidence of the extensive redevelopment of the large cattail and eel grass beds was not observed in this first survey of Par Pond. Future surveys during the growing seasons of 1995, 1996, and 1997 along with the evaluation of satellite date to map the areal extent of the macrophyte beds of Par Pond are planned.

  10. Pond sediment magnetite grains show a distinctive microbial community.

    PubMed

    Song, H-K; Sonkaria, S; Khare, V; Dong, K; Lee, H-T; Ahn, S-H; Kim, H-K; Kang, H-J; Lee, S-H; Jung, S P; Adams, J M

    2015-07-01

    Formation of magnetite in anaerobic sediments is thought to be enhanced by the activities of iron-reducing bacteria. Geobacter has been implicated as playing a major role, as in culture its cells are often associated with extracellular magnetite grains. We studied the bacterial community associated with magnetite grains in sediment of a freshwater pond in South Korea. Magnetite was isolated from the sediment using a magnet. The magnetite-depleted fraction of sediment was also taken for comparison. DNA was extracted from each set of samples, followed by PCR for 16S bacterial ribosomal RNA (rRNA) gene and HiSeq sequencing. The bacterial communities of the magnetite-enriched and magnetite-depleted fractions were significantly different. The enrichment of three abundant operational taxonomic units (OTUs) suggests that they may either be dependent upon the magnetite grain environment or may be playing a role in magnetite formation. The most abundant OTU in magnetite-enriched fractions was Geobacter, bolstering the case that this genus is important in magnetite formation in natural systems. Other major OTUs strongly associated with the magnetite-enriched fraction, rather than the magnetite-depleted fraction, include a Sulfuricella and a novel member of the Betaproteobacteria. The existence of distinct bacterial communities associated with particular mineral grain types may also be an example of niche separation and coexistence in sediments and soils, which cannot usually be detected due to difficulties in separating and concentrating minerals. PMID:25592636

  11. Dynamic mathematical model of high rate algal ponds (HRAP).

    PubMed

    Jupsin, H; Praet, E; Vasel, J L

    2003-01-01

    This article presents a mathematical model to describe High-Rate Algal Ponds (HRAPs). The hydrodynamic behavior of the reactor is described as completely mixed tanks in series with recirculation. The hydrodynamic pattern is combined with a subset of River Water Quality Model 1 (RWQM1), including the main processes in liquid phase. Our aim is to develop models for WSPs and aerated lagoons, too, but we focused on HRAPs first for several reasons: Sediments are usually less abundant in HRAP and can be neglected, Stratification is not observed and state variables are constant in a reactor cross section, Due to the system's geometry, the reactor is quite similar to a plugflow type reactor with recirculation, with a simple advection term. The model is based on mass balances and includes the following processes: *Phytoplankton growth with NO3-, NO2- and death, *Aerobic growth of heterotrophs with NO3-, NH4+ and respiration, *Anoxic growth of heterotrophs with NO3-, NO2- and anoxic respiration, *Growth of nitrifiers (two stages) and respiration. The differences with regard to RWQM1 are that we included a limiting term associated with inorganic carbon on the growth rate of algae and nitrifiers, gas transfers are taken into account by the familiar Adeney equation, and a subroutine calculates light intensity at the water surface. This article presents our first simulations. PMID:14510211

  12. Impacts of Size Structure on Intraguild Predation in Pond Communities

    NASA Astrophysics Data System (ADS)

    Crumrine, P. W.

    2005-05-01

    Size structure, the degree to which individuals in a population vary in size, can greatly influence the dynamics of intraguild predation (IGP) within ecological communities. I manipulated the degree of size structure within assemblages of IG predators and IG prey to examine impacts on the direction and intensity of IGP in communities of larval dragonflies and larval water beetles. In pond enclosure studies, Pachydiplax longipennis (IG prey) mortality was lower when exposed to size structured assemblages of Anax junius (IG predator) than when exposed to only large A. junius at the same density. Effects of size-structured assemblages of A. junius on shared prey, Ischnura verticalis, were similar to the effects each size class alone at the same density. Separate experiments with Dytiscid water beetle larvae as IG predators and size-structured assemblages of A. junius as IG prey suggest that IG prey size structure plays only a limited role in mediating shared prey survival. These experiments highlight the importance of size structure as a characteristic that may promote the coexistence of predators in IGP systems.

  13. Multiple Contaminant and Predatory Stressors in Experimental Pond Communities

    NASA Astrophysics Data System (ADS)

    Keeley, K.; Crumrine, P. W.; Barlow, P. F.

    2005-05-01

    Anthropogenic contaminants, such as agricultural pesticides found in aquatic systems, have the potential to negatively impact organisms via direct and indirect pathways. The magnitude of these indirect effects depends on the strength of the interactions through which they are propagated. We sought to determine how environmentally realistic levels of the insecticides endosulfan and malathion and the herbicide atrazine impact pond communities. We investigated the effects of these pesticides in mesocosm communities containing larval dragonflies (Anax junius), adult water bugs (Belostoma flumineum), and snails (Planorbella trivolvis). Dragonflies presented a moderate predatory threat to snails, as they affected snail behavior but not survival. Direct effects of pesticides on snails were limited, and pesticides only induced modest changes in snail behavior. All pesticides negatively influenced dragonfly survival and this was most pronounced in treatments with endosulfan. However, the reduction in dragonfly survival did not transmit benefits to snails that were detectable as changes in behavior or survival, as would be expected if dragonflies represented a stronger predatory threat. These results show that individuals in communities can be differentially impacted by contaminants, and indicate that strong indirect effects depend on the strength of underlying trophic interactions.

  14. Thermal storage case study: Combined building mass and cooling pond

    SciTech Connect

    Arnold, D.

    2000-07-01

    In 1994 a large U.K. credit card company decided to relocate and centralize its offices and operations from a number of city center sites to the outskirts on a green field site. The company decided that the concept for the new building should be environmentally friendly, i.e., naturally ventilated and cooled by openable windows. However, during initial studies there was concern over whether natural cooling and ventilation alone would be adequate to maintain thermal comfort during hot weather. The design solution was to provide a mix of passive and mechanical systems that could be switched in response to internal conditions and the prevailing weather. The object was to use passive features, i.e., the building thermal mass and storage and cooling effects of a pond, to maintain thermal comfort whenever possible and only switch to mechanical cooling under extreme conditions. The building was occupied progressively during the spring of 1997. The case study covers the period from the initial design concept to the end of the first 18 months of occupation.

  15. Chryse Basin channels: low-gradients and ponded flows.

    USGS Publications Warehouse

    Lucchitta, B.K.; Ferguson, H.M.

    1983-01-01

    Gradients on the floors of the Martian outflow channels that are derived from radar-elevation profiles across Lunae Planum and Chryse Basin have much lower values than those obtained from the U.S. Geological Survey's topographic map. Whereas the gradients of Maja and Ares Valles are similar to those of the catastrophic flood channels in the Scablands of Washington State, the gradients of Simud and Tiu Valles are essentially level, and the movement of fluids to the N poses problems. It is proposed that ponding may have formed lakes in depressions associated with the Valles Marineris grabens, ancient craters in the chaotic terrain area, and possibly even the regional low where most chaotic terrains occur. It is envisaged that lakes eventually overflowed, forming the present channels. When dams broke, floods were released catastrophically, with a final gigantic flood from the Valles Marineris system of troughs, which would have had sufficient head to move fluids across nearly level gradients through the Simud and Tiu channels. -P.Br.

  16. CFD study to determine the optimal configuration of aerators in a full-scale waste stabilization pond.

    PubMed

    Alvarado, Andres; Vesvikar, Mehul; Cisneros, Juan F; Maere, Thomas; Goethals, Peter; Nopens, Ingmar

    2013-09-01

    Aerated lagoons (ALs) are important variants of the pond wastewater treatment technology that have not received much attention in the literature. The hydraulic behaviour of ALs and especially the Facultative aerated lagoons (FALs) is very complex since the aeration in these systems is designed for oxygen transfer but not necessarily to create complete mixing. In this work, the energy expenditure of the aerators was studied by means of a scenario analysis. 3D CFD models (one phase and multiphase) of a 3 ha FAL in a waste stabilization pond system in Cuenca (Ecuador) were built for different configurations of aerators. The thrust produced by the aerators was modelled by an external momentum source applied as velocity vectors into the pond fluid. The predictions of a single phase model were in satisfactory agreement with experimental results. Subsequently, a scenario analysis assessing several aeration schemes with different numbers of aerators in operation were tested with respect to velocity profiles and residence time distribution (RTD) curves. This analysis showed that the aeration scheme with all 10 aerators switched on produces a similar hydraulic behaviour compared to using only 6 or 8 aerators. The current operational schemes comprise of switching off some aerators during the peak hours of the day and operating all 10 aerators during night. This current practice could be economically replaced by continuously operating 4 or 6 aerators without significantly affecting the overall mixing. Furthermore, a continuous mixing regime minimises the sediment oxygen demand enhancing the oxygen levels in the pond. PMID:23764602

  17. Winter performance of an urban stormwater pond in southern Sweden

    NASA Astrophysics Data System (ADS)

    Semadeni-Davies, Annette

    2006-01-01

    Evidence from cold regions in North America has shown that the performance of stormwater ponds differs between winter and summer. The pond hydraulics change seasonally, and winters have lowered removal efficiency due to a combination of an ice cover, cold water and de-icing salts. This study examines the function of the Bäckaslov stormwater pond under the more mild conditions of southern Sweden, where there are several snow and melt cycles per year.Event sampling in the summer of 1997 showed good removal efficiencies for nutrients, total suspended solids (TSS) and a selection of metals (Cd, Cu, Pb, Zn), but winter grab-tests taken in 1995-96 and 1997-98 suggest that the pond acts as a pollutant source under cold conditions. To better assess winter and spring pond performance, water at the inflow and outflow was sampled from January to April 2003. The low intensity of runoff delivery and slow inflow velocities meant that time- rather than flow-weighted sampling was used. Five consecutive events were sampled and analysed for TSS, chloride and the metals As, Cd, Cr, Cu, Hg, Ni, Pb and Zn. YSI probes were in place at both the inlet (pH, temperature) and outlet (pH, temperature, conductivity, dissolved oxygen) to determine the timing of pollution flows. In addition, profiles of the same quality indicators allowed snapshots of pond processes.De-icing salt has a major effect on pond hydraulics. Strong stratification occurred after each snowmelt-generated flow event and up to 80% of chloride could be retained by the pond. However, continuous conductivity measurements show that chloride is flushed between events. Ice changes retention times and causes oxygen depletion, but bed scour was not observed. Pond performance decreased during the winter and spring, albeit not as badly as the grab tests suggest. A seasonal comparison of the removal efficiencies showed that removal of Cd (75%) and Cu (49%) was about the same for summer and winter-spring, but removal of Pb, Zn and TSS

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

    PubMed Central

    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

  19. Revegetation of flue gas desulfurization sludge pond disposal sites

    SciTech Connect

    Artiola, J.F.

    1994-12-01

    A comprehensive search of published literature was conducted to summarize research undertaken to date on revegetation of flue gas desulfurization (FGD) waste disposal ponds. A review of the physical and chemical properties of FGD sludges and wastes with similar characteristics is also included in order to determine the advantages and limitations of FGD sludge for plant growth. No specific guidelines have been developed for the revegetation of FGD sludge disposal sites. Survey studies showed that the wide-ranging composition of FGD wastes was determined primarily by the sulfur dioxide and other flue gas scrubbing processes used at powerplants. Sulfate rich (>90%CaSO{sub 4}) FGD sludges are physically and chemically more stable, and thus more amenable to revegetation. Because of lack of macronutrients and extremely limited microbial activity, FBD sludge ponds presented a poor plant growth environment without amendment. Studies showed the natural process of inoculation of the FGD sludge with soil microbes that promote plant growth be can after disposal but proceeded slowly. Revegetation studies reviewed showed that FGD sludges amended with soils supported a wider variety of plant species better and longer than abandoned FGD ponds. Two major types of plants have been successful in revegetation of FGD waste ponds and similar wastes: salt-tolerant plants and aquatic plants. A comprehensive list of plant species with potential for regetation of FGD sludge disposal pond sites is presented along with successful revegetation techniques.

  20. Par Pond vegetation status Summer 1995 -- September survey descriptive summary

    SciTech Connect

    Mackey, H.E. Jr.; Riley, R.S.

    1995-09-01

    The water level of Par Pond was lowered approximately 20 feet in mid-1991 in order to protect downstream residents from possible dam failure suggested by subsidence on the downstream slope of the dam and to repair the dam. This lowering exposed both emergent and nonemergent macrophyte beds to drying conditions resulting in extensive losses. A survey of the emergent shoreline aquatic plant communities began in June 1995, three months after the refilling of Par Pond to approximately 200 feet above mean sea level and continued with this mid-September survey. Communities similar to the pre-drawdown Par Pond aquatic plant communities are becoming re-established; especially, beds of maidencane, lotus, waterlily, and watershield are now extensive and well established. Cattail occurrence continues to increase, but large beds common to Par Pond prior to the drawdown have not formed. Future surveys during the late growing seasons of 1995, and throughout 1996 and 1997, along with the evaluation of satellite data to map the areal extent of the macrophyte beds of Par Pond, are planned.