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1

Sediment-water exchange in shallow water estuarine sediments  

Microsoft Academic Search

Pore water distributions are described in Quatermaster Harbor, Puget Sound over the period of 1976-1979 along with an in situ tracer experiment designed to monitor the transport of water across the sediment-water interface. Transport processes in sediment pore waters of the Sound were dominated by molecular diffusion in the top few centimeters with animal activity being the most important transport

Steven Emerson; Richard Jahnke; David Heggie

1984-01-01

2

Determination of Domestic Water Consumption Rates under Varying Water Pressures.  

National Technical Information Service (NTIS)

An experimental study of water consumption in Mayaguez, Puerto Rico determined that pressure is not related to domestic consumption. The cause of variations in the city's domestic consumption was not determined. Data used in the study are tabulated. A bri...

L. A. Nunez M. F. de Vera J. M. Fidalgo

1969-01-01

3

Efficient heating and domestic hot water apparatus  

SciTech Connect

An efficient, compact boiler system providing both heating water for heating an enclosed space, such as a home, and domestic hot water for washing and similar purposes, has a limited fluid capacity primary heating coil within a combustion chamber. The coil supplies heated water to a larger capacity storage boiler located directly below the primary boiler and connected to it by header pipes which themselves form a manifold into which the primary coil is connected. The storage boiler distributes the heated water through the heating system. An elongated secondary heating coil within the boiler heats the domestic hot water supply by heat transfer from the boiler water. The return header pipe discharges heated water directly into the interior loop of the secondary coil to quickly heat the domestic hot water when the burner is ''on''.

Gerstmann, J.; Pompei, F.

1980-09-16

4

Effektiv brugsvandsopvarmning. (Efficient domestic hot water heating).  

National Technical Information Service (NTIS)

The aim was to investigate alternative, electrically or gas/oil heated, domestic hot water systems to find potentials for minimum heat loss from pipes and hot water tanks. Experiments were carried out on a 10 l electrically heated hot water heater and a 2...

J. M. Schultz

1991-01-01

5

Water-Using Equipment: Domestic  

SciTech Connect

Water management is an important aspect of energy engineering. This article addresses water-using equipment primarily used for household purposes, including faucets, showers, toilets, urinals, dishwashers, and clothes washers, and focuses on how the equipment can be optimized to save both water and energy. Technology retrofits and operation and maintenance changes are the primary methods discussed for water and energy conservation. Auditing to determine current consumption rates is also described for each technology.

Solana, Amy E.; McMordie-Stoughton, Katherine L.

2006-01-24

6

Sediment-water exchange in shallow water estuarine sediments  

SciTech Connect

Pore water distributions are described in Quatermaster Harbor, Puget Sound over the period of 1976-1979 along with an in situ tracer experiment designed to monitor the transport of water across the sediment-water interface. Transport processes in sediment pore waters of the Sound were dominated by molecular diffusion in the top few centimeters with animal activity being the most important transport process below this to 20-70 cm. The value of the transport parameter for the nonlocal process is 1 to 5 to the minus 7th power/second. Using this value and pore water concentrations it can be demonstrated that animal activities are the dominant process driving sediment-water dissolved fluxes except for elements with dramatic bottom water-pore water concentration gradients. For the metals Fe, Mn, Cu, Ni, and Cd the dominant transport mechanism depends on the depth at which the metal is released to the pore waters. Probably the most important effect of biological activity on metal remobilization is the removal of sulfide from the pore waters, via ventilation of sediments with toxic overlying water, allowing the enrichment of dissolved metals which might otherwise be very low in concentration due to insoluble sulfide formation. The result is a greatly enhanced flux of metals to the bottom waters. 40 references, 7 figures, 4 tables.

Emerson, S.; Jahnke, R.; Heggie, D.

1984-05-01

7

Quantifying Urban Water Subsidies with Hydrological Tracers of Domestic Water  

NASA Astrophysics Data System (ADS)

Connections between urban hydrological systems and human water infrastructure are well established. Interactions between these systems occur at a wide range of scales, from large inter-basin transfers to individual leaking pipes. However, much of the interest in these connections arises from practical considerations, for example, substantially altered in-stream flow or the presence/absence of sewage in surface water systems. Less recognized is that in smaller urban catchments, daily water flux through human water distribution systems is often much larger than low flow surface water flux from the catchment. As infrastructure ages and cross-connections grow, transfers from the substantial human fluxes to the catchment will increasingly subsidize urban water budgets. Tools for quantifying the contribution of this subsidy to urban hydrological systems can clarify both practical questions for urban managers and our understanding of flow generation in catchments. Stream water chemistry from a multi-year sampling campaign in Nine Mile Run (Pittsburgh, PA) is used to examine potential hydrological tracers of human domestic water. In particular, we examine the use of fluoride added in precise quantities as a dental health supplement as a tracer of human domestic water (e.g., drinking and waste water). While fluoride is not necessarily a conservative tracer, equilibrium reactions governing fluoride solubility generally require substantially higher cationic concentrations than those observed in surface water chemistry. Further, during periods where human subsidies dominate (e.g., water line breaks or hydrant flushes discharging to the stream) fluoride concentrations generally approach the concentration added to domestic water. We use multiple modeling approaches to demonstrate the appropriateness of fluoride as a tracer, infer contributions of human domestic water to the hydrologic budget, and explore fluoride dynamics in the Nine Mile Run basin. A fluoride tracer is particularly exciting due to applicability in a large number of urban systems fluoridating drinking waters and due to robust, high-frequency measurement capacity via off-the-shelf drinking water treatment technologies.

Bain, D. J.; Sikora, M. T.; Wozniak, E.; Fisher, K. R.; Carr, J.; Elliott, E. M.

2011-12-01

8

CHANGES IN SEDIMENT - WATER COLUMN PHOSPHORUS INTERACTIONS FOLLOWING SEDIMENT DISTURBANCE  

Technology Transfer Automated Retrieval System (TEKTRAN)

Sediment P dynamics are a constantly changing group of parameters that control P concentrations in surface water. Removal of existing sediments and deposition of new sediments will change the physiochemical parameters controlling P transport in ditches, however these phenomenon are not well documen...

9

Solar Domestic Water Heating Technology: Market Barriers and Adoption Strategies  

Microsoft Academic Search

This paper analyzes the United States' domestic water heating industry and solar domestic water heating technology adoption from the standpoint of Porter's five forces model and the technology adoption life cycle model. Using Porter's five forces model, the key barriers to entry for solar water heating technology are high buyer price sensitivity and unequal access to distribution channels. In the

Alan J. Fitzmorris

2010-01-01

10

Water diuresis in the domestic fowl  

PubMed Central

1. The exteriorization of ureters in domestic fowls allows the collection of urine uncontaminated by faeces. 2. When water is administered by stomach tube to a fowl, water is stored in the crop, from which it is slowly released into the proventriculus. 3. Immediately after water gavage, there is a sharp rise of urine flow accompanied by an increase in endogenous creatinine excretion and a fall in the osmolarity of the urine. This initial increase in urine flow is of short duration, and is followed by a normal curve of diuresis with a peak at about 90 min after hydration. 4. The first rise in urine flow following the filling of the crop appears to be of reflex origin, as distension of the crop with paraffin produces an enhanced excretion of urine and of creatinine. 5. Changes in urine flow and in creatinine excretion are closely correlated. 6. After water deprivation for 18 hr, the urine is slightly hyptertonic to blood. The maximum urine concentration observed was of the order of 600 m-osmole/l.

Dicker, S. E.; Haslam, J.

1966-01-01

11

POSSIBILITY OF REDUCING DOMESTIC WATER SHORTAGE DURING DROUGHT BY POPULARIZATION OF WATER SAVING APPLIANCES  

NASA Astrophysics Data System (ADS)

I studied possibility of reducing domestic water shortage during drought by popularization of water saving appliances. Dometic water demand can be reduced by 30% by popularization of water saving appliances. If domestic water demand is reduced by 25%, domestic water don't run short in case of drought equal to drought in 1994. If water demand is reduced by 15%, shortage of domestic water is allowable. If subsidy policy is adopted to reduce water demand by 15% within 10 years, every residents must pay 200 yen every month for operating fund.

Tsuda, Morimasa

12

Energy-saving device for domestic water heaters  

Microsoft Academic Search

An energy saving device for use in connection with a heat insulated storage vessel in a domestic hot-water system is disclosed. When there is no demand for hot water, water contained in the vessel is heated in an electric through-flow heater and circulated by gravity, with the heated water rising into the vessel through an outflow pipe of the vessel

Kalmanoviz

1980-01-01

13

Optimization of Domestic Hot Water Production and Energy Economy.  

National Technical Information Service (NTIS)

Factors that effect on domestic hot water production were studied in laboratory conditions in various heating systems. Whether over dimensioning or ready-to-operate loss have influence on the energy economy in these systems was also researched. The effect...

K. Tormonen

1987-01-01

14

Energy conservation in the production of domestic hot water  

NASA Astrophysics Data System (ADS)

Improvements in energy efficiency in existing buildings and the construction of energy efficient buildings are discussed with emphasis on water heating. Cost effective measures proposed include fitting an 80-mm insulating jacket to the hot water storage cylinder, using time switches, fitting thermostatic control systems to boiler based central heating, and storing domestic hot water at a lower temperature. Research into the recovery of heat from waste water, the use of cold water detergents, and the use of heat pumps is urged.

1981-12-01

15

Component Description of Sediment-Water Microcosms.  

National Technical Information Service (NTIS)

The development and application of complementary variables (potential and flux) for modeling environmental systems are illustrated for the hydraulic and dissolved oxygen subsystems of laboratory microcosms. These sediment-water, semi-continuous flow micro...

J. Hill D. B. Porcella

1974-01-01

16

Domestic Wash-Water Reclamation Using an Aerospace-Developed Water Recovery Subsystem.  

National Technical Information Service (NTIS)

A prototype aerospace distillation water recovery subsystem was tested to determine its capability to recover potable water from domestic wash water. A total of 0.0994 cu m (26.25 gallons) of domestic wash water was processed over a 7-day period at an ave...

J. B. Hall

1973-01-01

17

Prototype Solar Domestic Hot Water Systems.  

National Technical Information Service (NTIS)

Construction of a double wall heat exchanger using soft copper tube coiled around a hot water storage tank was completed and preliminary tests were conducted. Solar transport water to tank potable water heat exchange tests were performed with a specially ...

1978-01-01

18

Domestication  

Microsoft Academic Search

Tradition dictates that domestication is degenerative and that psychology is misled by research on the domestic rat. However, a review of the literature indicates that domestication is adaptive for conditions of captivity, so that some behaviors (e.g., learning) may increase in potential while others (e.g., sociality) are diminished via a raised threshold. Critical implications for psychology are that research is

Robert Boice; Örjan Carlborg; Irina Plyusnina; Francois Besnier; Daniela Hedwig; Susann Lautenschläger; Doreen Lorenz; Jenny McIntosh; Christof Neumann; Henning Richter; Claudia Zeising; Rimma Kozhemyakina; Olesya Shchepina; Jürgen Kratzsch; Lyudmila Trut; Daniel Teupser; Joachim Thiery; Torsten Schöneberg; Leif Andersson; Svante Pääbo

1973-01-01

19

Effects of Alum Water Treatment Sludge on Domestic Wastewater Sludges.  

National Technical Information Service (NTIS)

Research on the effects of alum sludge generated by water treatment plants on the properties of domestic waste water sludges is reported. Phase I of the three phase investigation was concerned with the effects of raw sewage containing alum sludge on an ac...

M. E. Burman

1975-01-01

20

Domestic hot water and solar energy in Ireland  

Microsoft Academic Search

The ability of two solar energy systems to supply domestic hot-water requirements in Ireland is studied by means of a computer simulation model of a system which uses a commercially available solar panel. The water-heating systems and the analysis of system performance are described. The model indicates that, for the cost of the systems to be economically justifiable in comparison

Francis Hand; Barfour Asare; John Haslett

1977-01-01

21

Benefits of insulating domestic hot water pipework. Research memo  

Microsoft Academic Search

A computer program was developed to simulate a domestic hot-water system and was used to investigate the likely losses of energy and hot water in distribution pipework. Predictions were obtained on the effects of insulating pipework and the improvements in system efficiency for various daily draw-off patterns.

1986-01-01

22

Determination of domestic flushing water consumption in Hong Kong  

Microsoft Academic Search

Purpose – To determine the domestic flushing water consumption for a building development. Design\\/methodology\\/approach – A statistic mathematical model is proposed and the model parameters are sampled with the Monte Carlo sampling technique. The frequency distribution of the parameters for Hong Kong is identified from the survey results of the water closet usage patterns in five typical residential building estates.

L. T. Wong; K. W. Mui

2005-01-01

23

A CONSIDERATION OF DOMESTIC WATER FORECASTING WITH MULTIVARIATE ANALYSIS TECHNIQUE  

NASA Astrophysics Data System (ADS)

The results of forecasting domestic water demand in the long term are important for planning water supply facilities and operation and management systems. In Japan, recently, domestic water demand has been decreasing because of the progress of a water saving society such as spread of water-saving equipment. The trend methods has been used for forecasting water demand, however, water demand structures are complicated due to the variation of factors affecting them. It has therefore become difficult to forecast domestic water demand by the trend methods. Some waterworks have used multivariate analysis method using quantification method theory 1 for water demand forecasting. However, the method includes a issue not to be able to set in the changes of prescriptive factors in the future. The selection of explanatory variables is also a large issue. The aim of this study was to analyze changes of the prescriptive factors using quantification theory type 1 by the results of questionnaire surveys carried out at intervals and to reflect how far the water demand should be expressed on practical level focused on the selection of explanatory variables. As the results, changes of the factors and its contribution were revealed across the age. However, results of the water demand forecasting were not enough accurate because of the changes of factors. And, the considerations in water demand forecasting using multivariate analysis were mentioned.

Shimizu, Toshiyuki; Higashi, Yusuke; Taniguchi, Kumiko; Yamada, Kiyoshi

24

DOMESTIC ROOFTOP WATER HARVESTING A CASE STUDY  

Microsoft Academic Search

Although water is as important for survival of human being as much as food, air etc, but hardly any attention is paid for its economical use and conservation of this precious resource. Due to indiscriminate pumping of ground water, the water table is going down abnormally and if the problem is not given a serious look, then the future generations

Arun Kumar Dwivedi; Sudhir Singh Bhadauria

25

"ITM" (INLAND WATERS SEDIMENT TESTING MANUAL)  

EPA Science Inventory

EPA public web site providing the national sediment testing manual for dredged material proposed for discharge in waters of the U.S. Description from site: "The "Evaluation of Dredged Material Proposed for Dischage in Waters of the U.S. - Testing Manual", commonly referred to as...

26

Par Pond Fish, Water, and Sediment Chemistry  

SciTech Connect

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.

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

1996-06-01

27

Assessment of domestic water quality: case study, Beirut, Lebanon  

Microsoft Academic Search

In urban cities, the environmental services are the responsibility of the public sector, where piped water supply is the norm\\u000a for urban household. Likewise, in Beirut City (capital of Lebanon) official water authorities are the main supplier of domestic\\u000a water through a network of piping system that leaks in many areas. Beirut City and its suburbs are overpopulated since it

Samira Ibrahim Korfali; Mey Jurdi

2007-01-01

28

Suspended sediment transport, sedimentation, and resuspension in Lake Houston, Texas: Implications for water quality  

Microsoft Academic Search

Lake Houston is a man-made reservoir located northeast of Houston, Texas. The purpose of this investigation was to document suspended sediment transport, sedimentation, and resuspension in the lake with a view towards estimating the influence of sedimentation on water quality. Sediment traps were placed in strategic locations in the lake to collect suspended sediments. Samples were analyzed for bulk density,

Jane M. Matty; John B. Anderson; Robert B. Dunbar

1987-01-01

29

Legionella Infection Risk from Domestic Hot Water  

PubMed Central

We investigated Legionella and Pseudomonas contamination of hot water in a cross-sectional multicentric survey in Italy. Chemical parameters (hardness, free chlorine, and trace elements) were determined. Legionella spp. were detected in 33 (22.6%) and Pseudomonas spp. in 56 (38.4%) of 146 samples. Some factors associated with Legionella contamination were heater type, tank distance and capacity, water plant age, and mineral content. Pseudomonas presence was influenced by water source, hardness, free chlorine, and temperature. Legionella contamination was associated with a centralized heater, distance from the heater point >10 m, and a water plant >10 years old. Furthermore, zinc levels of <20 ?g/L and copper levels of >50 ?g/L appeared to be protective against Legionella colonization. Legionella species and serogroups were differently distributed according to heater type, water temperature, and free chlorine, suggesting that Legionella strains may have a different sensibility and resistance to environmental factors and different ecologic niches.

Montagna, M. Teresa; Romano-Spica, Vincenzo; Stampi, Serena; Stancanelli, Giovanna; Triassi, Maria; Neglia, Rachele; Marchesi, Isabella; Fantuzzi, Guglielmina; Tato, Daniela; Napoli, Christian; Quaranta, Gianluigi; Laurenti, Patrizia; Leoni, Erica; De Luca, Giovanna; Ossi, Cristina; Moro, Matteo; D'Alcala, Gabriella Ribera

2004-01-01

30

Legionella Infection Risk from Domestic Hot Water  

Microsoft Academic Search

We investigated Legionella and Pseudomonas con- tamination of hot water in a cross-sectional multicentric sur- vey in Italy. Chemical parameters (hardness, free chlorine, and trace elements) were determined. Legionella spp. were detected in 33 (22.6%) and Pseudomonas spp. in 56 (38.4%) of 146 samples. Some factors associated with Legionella contamination were heater type, tank distance and capacity, water plant age,

Paola Borella; M. Teresa Montagna; Vincenzo Romano-Spica; Serena Stampi; Giovanna Stancanelli; Maria Triassi; Rachele Neglia; Isabella Marchesi; Guglielmina Fantuzzi; Daniela Tatò; Christian Napoli; Gianluigi Quaranta; Patrizia Laurenti; Erica Leoni; Giovanna De Luca; Cristina Ossi; Matteo Moro; Gabriella Ribera D'Alcalà

2004-01-01

31

A solar energy system for domestic hot water  

Microsoft Academic Search

The design, operation, and domestic hot water heating performance of a solar energy system are described. This system is to be retrofitted and integrated into the existing conventional mechanical system at a large museum, where it is not only expected to provide substantial fuel cost savings but is also planned to serve as an exhibit of an actual working solar

T. J. McNamara

1977-01-01

32

Comparative analysis of six generic solar domestic hot water systems  

Microsoft Academic Search

Results were analyzed from experiments on six solar domestic hot water systems tested at National Bureau of Standards. Use of pumps, fans, controls, and solenoid valves in the pumped systems resulted in high parasitic energy consumption. Storage losses from double tank systems were greater than expected due to poor storage tank insulation. Direct systems performed better than indirect systems as

R. Farrington; D. Noreen; L. M. Murphy

1980-01-01

33

Promising freeze protection alternatives in solar domestic hot water systems  

Microsoft Academic Search

Since the gains associated with solar thermal energy technologies are comparatively small in relation to the required capital investment, it is vital to maximize conversion efficiency. While providing the necessary function of freeze protection, the heat exchanger commonly included in solar domestic water heating systems represents a system inefficiency. This thesis explores two alternate methods of providing freeze protection without

1997-01-01

34

Water saving potential of domestic water reuse systems using greywater and rainwater in combination  

Microsoft Academic Search

For a sustainable urban future, society must move towards the goal of efficient and appropriate water use. Reuse of domestic greywater and rainwater has a significant role to play in this task. In this study, rainfall time series have been used in conjunction with estimates of domestic water appliance usage generated by the Monte-Carlo simulation technique to predict long term

A. Dixon; D. Butler; A. Fewkes

1999-01-01

35

Use of tracers and isotopes to evaluate vulnerability of water in domestic wells to septic waste  

USGS Publications Warehouse

In Nebraska, a large number (>200) of shallow sand-point and cased wells completed in coarse alluvial sediments along rivers and lakes still are used to obtain drinking water for human consumption, even though construction of sand-point wells for consumptive uses has been banned since 1987. The quality of water from shallow domestic wells potentially vulnerable to seepage from septic systems was evaluated by analyzing for the presence of tracers and multiple isotopes. Samples were collected from 26 sand-point and perforated, cased domestic wells and were analyzed for bacteria, coliphages, nitrogen species, nitrogen and boron isotopes, dissolved organic carbon (DOC), prescription and nonprescription drugs, or organic waste water contaminants. At least 13 of the 26 domestic well samples showed some evidence of septic system effects based on the results of several tracers including DOC, coliphages, NH4+, NO3-, N2, ?? 15N[NO3-] and boron isotopes, and antibiotics and other drugs. Sand-point wells within 30 m of a septic system and <14 m deep in a shallow, thin aquifer had the most tracers detected and the highest values, indicating the greatest vulnerability to contamination from septic waste. Copyright ?? 2005 National Ground Water Association.

Verstraeten, I. M.; Fetterman, G. S.; Meyer, M. J.; Bullen, T.; Sebree, S. K.

2005-01-01

36

Architectural integration of solar systems for domestic water heating  

SciTech Connect

Architectural designs are suggested for solar domestic water heating units (collectors and water storage tanks) in multifamily houses up to four stories. The designs are based on different combinations of standard units assembled to fit the different architectural types as designed by the Israeli Ministry of Housing. In addition, an approach is presented that suggests a unique design of the upper floor apartment with inclined roofs so the solar system becomes an integral part of the structure. Several solutions are suggested and compared.

Ishai, E.

1987-01-01

37

Improving the efficiency of domestic hot-water systems  

Microsoft Academic Search

The siting of hot-water cylinders remote from taps, and the use of long interconnecting pipework, does not give energy-efficient systems. A computer program was developed to simulate the domestic hot-water system in dwellings, and is used to predict the effects of several parameters such as cylinder insulation, pipework insulation and dead-leg length. An efficient system would comprise a foam-insulated cylinder,

1986-01-01

38

1. DOMESTIC WATER SUPPLY TREATMENT HOUSE, ON PENSTOCK ABOVE SAR1. ...  

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

1. DOMESTIC WATER SUPPLY TREATMENT HOUSE, ON PENSTOCK ABOVE SAR-1. VIEW TO NORTWEST. - Santa Ana River Hydroelectric System, SAR-1 Domestic Water Supply Treatment House, Redlands, San Bernardino County, CA

39

Toxicity Evaluation of Lower Fox River Water and Sediments.  

National Technical Information Service (NTIS)

Many persistent, xenobiotic compounds have been identified from Lower Fox River water, biota, sediment, and effluent discharges; some of which are suspected of causing adverse effects to aquatic organisms. Water and sediment were collected as grab samples...

G. J. Lien K. E. Biesinger L. E. Anderson E. N. Leonard M. A. Gibbons

1986-01-01

40

Review of domestic water conservation practices in Saudi Arabia  

NASA Astrophysics Data System (ADS)

The Kingdom of Saudi Arabian (KSA) has a substantial water shortage problem where water demand far exceeds water resources sustainable yields. This fact has motivated the Ministry of Water and Electricity (MOWE) to launch a massive water conservation awareness program to enhance water-using efficiency in the country. The MOWE among other water awareness activities has introduced a four-stage program of free distribution of water conservation tools. This research reviewed the domestic water conservation awareness program in Saudi Arabia and assessed the program performance through conducting questionnaire surveys. The latter was designed and implemented in Al-Khobar city in the Eastern Province to measure public awareness regarding water issues. The survey started on April 28, 2012, and continued for 3 weeks. A total of 197 questionnaires were completed. The survey results showed a relatively low awareness among respondents about water shortage problem in the Kingdom. A low percentage of respondents have water conservation tools installed in their houses, but a high percentage is willing to buy and install water conservation tools. The majority of respondents consider the water price low and are willing to pay more for water. The respondents' feedback highlighted the need to improve the current water conservation awareness program.

Ouda, Omar K. M.; Shawesh, Ahmad; Al-Olabi, Tareq; Younes, Firas; Al-Waked, Rafat

2013-06-01

41

Heat consumption for preparing domestic hot water in hospitals  

Microsoft Academic Search

This study analyses heat consumption for heating domestic water in large hospital facilities with over 600 hospital beds. The tests were carried out in 2 hospitals: the 715-bed University Hospital in Bydgoszcz and the 690-bed Provincial Hospital. The tests were performed over a period of 4 years: 2005–2008 for the first hospital and 2003–2006 for the second.The aim of this

Janusz Bujak

2010-01-01

42

Consumer's guide to buying solar domestic hot water. [Monograph  

SciTech Connect

This guide explains how a solar domestic hot water (DHW) system works and what is involved in installing one in the home. Like any other major property improvement, a solar DHW system should be carefully considered in terms of costs, benefits, local building regulations, and the system's ability to provide the owner's needs. The guide covers siting, system sizing, financing, warranties, installation, and maintenance. It also provides step-by-step instructions and worksheets for an economic investment analysis. 1 table, 9 figures.

Not Available

1982-01-01

43

IMPACT OF GREY WATER HEAT RECOVERY ON THE ELECTRICAL DEMAND OF DOMESTIC HOT WATER HEATERS  

Microsoft Academic Search

Grey water heat exchangers (GWHE) are used to recuperate part of the energy contained in grey waters. The configuration used in this study recuperates part of the energy contained in the grey water from showers to pre-heat domestic hot water. Previous simulations studies have shown that this configuration can recuperate part of the energy that would otherwise be lost and

Parham Eslami-nejad; Michel Bernier

2009-01-01

44

The effect of domestic ion-exchange water softeners on the microbiological quality of drinking water  

Microsoft Academic Search

This paper covers the testing and evaluation of the impact an ion-exchange water softener has on the microbiological quality of water. Water quality was assessed in two situations, firstly in normal domestic use and secondly under microbial shock loading conditions in the laboratories at Cranfield University. This study was undertaken to determine whether the passage of water through an ion-exchange

Simon A Parsons

2000-01-01

45

Patterns, structures and regulations of domestic water cycle systems in China  

NASA Astrophysics Data System (ADS)

Domestic water cycle systems serving as one critical component of artificial water cycle at the catchment's scale, is so closely related to public healthy, human rights and social-economic development, and has gained the highest priority in strategic water resource and municipal infrastructure planning. In this paper, three basic patterns of domestic water cycle systems are identified and analyzed, including rural domestic water system (i.e. primary level), urban domestic water system (i.e. intermediate level) and metropolitan domestic water system (i.e. senior level), with different "abstract-transport-consume-discharge" mechanisms and micro-components of water consumption (such as drinking, cooking, toilet flushing, showering or cleaning). The rural domestic water system is general simple with three basic "abstract-consume-discharge" mechanisms and micro-components of basic water consumption such as drinking, cooking, washing and sanitation. The urban domestic water system has relative complex mechanisms of "abstract-supply-consume-treatment-discharge" and more micro-components of water consumption such as bath, dishwashing or car washing. The metropolitan domestic water system (i.e. senior level) has the most complex mechanisms by considering internal water reuse, external wastewater reclamation, and nutrient recycling processes. The detailed structures for different water cycle pattern are presented from the aspects of water quantity, wastewater quality and nutrients flow. With the speed up of urbanization and development of social-economy in China, those three basic patterns are interacting, transforming and upgrading. According to the past experiences and current situations, urban domestic water system (i.e. intermediate level) is the dominant pattern based on indicator of system number or system scale. The metropolitan domestic water system (i.e. senior level) is the idealized model for the future development and management. Current domestic water system management efforts typically fail in China, because the approach is generally narrowly-focused and fragmented. This paper put forward a total-process control framework following the water and pollutants (or nutrients) flows along the dualistic domestic water cycle process. Five key objectives of domestic water cycle system regulation are identified including water use safety, water use equity, water saving, wastewater reduction and nutrient recycling. Comprehensive regulatory framework regarding administrative, economic, technical and social measures is recommended to promote sustainable domestic water usage and demand management. Considering the relatively low affordability in rural area, economic measures should be mainly applied in urban domestic water systems and metropolitan domestic water systems. Engineering or technological measures which are suitable to the three domestic water cycle systems are discussed respectively.

Chu, Junying; Wang, Hao; Wang, Jianhua; Qin, Dayong

2010-05-01

46

Suspended sediment transport, sedimentation, and resuspension in Lake Houston, Texas: Implications for water quality  

Microsoft Academic Search

Lake Houston is a man-made reservoir located northeast of Houston, Texas. The purpose of this investigation was to document\\u000a suspended sediment transport, sedimentation, and resuspension in the lake with a view towards estimating the influence of\\u000a sedimentation on water quality. Sediment traps were placed in strategic locations in the lake to collect suspended sediments.\\u000a Samples were analyzed for bulk density,

Jane M. Matty; John B. Anderson; Robert B. Dunbar

1987-01-01

47

Wild or domesticated: DNA analysis of ancient water buffalo remains from north China  

Microsoft Academic Search

Recent zooarchaeological studies on water buffalo (Bubalus sp.) remains from China and south Asia question the traditional view that water buffalo were first domesticated in Neolithic China over 7000years ago. The results from several recent population genetic studies of modern domesticated buffalo (Bubalus bubalis) are not consistent with each other, placing the original center of buffalo's domestication in south Asia,

Dongya Y. Yang; Li Liu; Xingcan Chen; Camilla F. Speller

2008-01-01

48

CONTAMINATED MARINE SEDIMENTS: WATER COLUMN AND INTERSTITIAL TOXIC EFFECTS  

EPA Science Inventory

The toxicity that contaminated sediments may introduce into the water column has not been measured extensively. n order to quantify this potential toxicity, the seawater overlying two uncontaminated and three contaminated marine sediments was evaluated in the laboratory with the ...

49

An inverted solar water heater for domestic hot water  

Microsoft Academic Search

An inverted solar water heater may be integrated into new buildings or attached to the south wall of an existing house. The system incorporates adjustable reflectors which deflect light onto a horizontal black absorber plate which rests on top of glazing. Above the absorber plate is a water-filled bag which collects the heat and is covered by insulation. Convection and

Heeschen

1979-01-01

50

Investigation of Water Quality in Domestic Water Systems.  

National Technical Information Service (NTIS)

The objective of the research was to determine the metal contents (zinc, copper, lead, cadmium and iron) in drinking waters transmitted by galvanized steel pipes and copper pipes. Water samples were taken from 17 buildings in New Jersey, New York and Mass...

L. K. Wang D. B. Aulenbach W. Y. W. Chan

1984-01-01

51

Domestic water and sanitation as water security: monitoring, concepts and strategy.  

PubMed

Domestic water and sanitation provide examples of a situation where long-term, target-driven efforts have been launched with the objective of reducing the proportion of people who are water-insecure, most recently through the millennium development goals (MDGs) framework. Impacts of these efforts have been monitored by an increasingly evidence-based system, and plans for the next period of international policy, which are likely to aim at universal coverage with basic water and sanitation, are being currently developed. As distinct from many other domains to which the concept of water security is applied, domestic or personal water security requires a perspective that incorporates the reciprocal notions of provision and risk, as the current status of domestic water and sanitation security is dominated by deficiency This paper reviews the interaction of science and technology with policies, practice and monitoring, and explores how far domestic water can helpfully fit into the proposed concept of water security, how that is best defined, and how far the human right to water affects the situation. It is considered that they fit well together in terms both of practical planning of targets and indicators and as a conceptual framework to help development. The focus needs to be broad, to extend beyond households, to emphasize maintenance as well as construction and to increase equity of access. International and subnational monitoring need to interact, and monitoring results need to be meaningful to service providers as well as users. PMID:24080628

Bradley, David J; Bartram, Jamie K

2013-09-30

52

The lipid geochemistry of interstitial waters of recent marine sediments  

SciTech Connect

To elucidate the nature of biogeochemical processes occurring at the water-sediment interface, the authors have analyzed fatty acids, n-alkanes and sterols contained in interstitial waters collected from oxic and anoxic marine sediments in the eastern and western intertropical Atlantic Ocean and in the Arabian Sea. Lipid concentrations in interstitial waters vary widely and are generally much higher than concentrations encountered in the overlying sea water. Higher concentrations in interstitial water are observed in environments favorable for organic input and preservation of the organic matter in the water column and in the surficial sediment. The analysis of biogeochemical markers in the various media of occurrence of the organic matter such as sea water, suspended particles, settling particles and sediment is discussed in terms of differences existing between these media and bio-transformations of the organic matter at the water-sediment interface.

Saliot, A.; Brault, M.; Boussuge, C. (l'Universite Pierre et Marie Curie, Paris (France))

1988-04-01

53

Water and sediment quality in a tropical swamp used for agricultural and oil refining activities.  

PubMed

The Godineau Swamp in Trinidad receives anthropogenic input from agricultural and oil refining activities, sewage and domestic waste. This study was conducted in order to provide a comprehensive baseline dataset for the swamp, to assess water and sediment quality in the swamp, and to identify hotspots and possible sources of pollutants to the swamp. Ten sampling stations were established in the swamp during April/May and July 2002. Water quality parameters monitored included physicochemical measurements (pH, temperature, dissolved oxygen and salinity), total suspended solids, and nutrients (ammonia, nitrites, nitrates and total phosphorus). Sediments were analyzed for hydrocarbons, heavy metals and total organic carbon. Temperatures and pH of water in the swamp were ambient; dissolved oxygen was low in many instances (<3 mg/L). In the dry season, there was saltwater intrusion along the Oropuche River up to the most easterly station. Levels of ammonia and phosphorus concentrations were suggestive of periodic inputs of agricultural and domestic wastes. Hydrocarbons concentrations in sediment were above ambient levels and suggestive of contamination from industrial activities. Sediments from the Godineau River contained elevated nutrients, hydrocarbons, metals and TOC compared with other stations. The results of this study indicate some degree of pollution of the Godineau swamp, which prompts the need for the implementation of measures beneficial for wise use of the swamp. PMID:21240702

Norville, Wendy; Banjoo, Darryl

2011-01-01

54

Thermal-energy stores for supplying domestic hot-water and space-heating  

Microsoft Academic Search

Factors influencing the ability of a conventional domestic hot-water tank to deliver domestic hot water rapidly have been culled, collated or assessed experimentally. It has been deduced that, with a horizontal-axis coiled, finned-type, heat exchanger--immersed in the traditional domestic hot-water tank--for extracting heat from the tank where and Ra are the mean Nusselt and Rayleigh numbers, respectively, for the freely-convecting

L. P. Chauvet; S. D. Probert; D. J. Nevrala

1994-01-01

55

Benthic invertebrate bioassays with toxic sediment and pore water  

USGS Publications Warehouse

The relative sensitivities of bioassays to determine the toxicity of sediments were investigated and three methods of making the sample dilutions required to generate dose-response relationships were compared. The assays studied were: (a) Microtox(R), a 15-min assay of Photobacterium phosphoreum bioluminescence inhibition by pore water; (b) 48-h Daphnia magna lethality test in pore water; (c) 10-d subchronic assay of lethality to and reduction of weight gain by Chironomus tentans performed in either whole sediment or pore water; (d) 168-h acute lethality assay of Hexagenia limbata in either whole sediment or pore water. The three methods of diluting sediments were: (a) extracting pore water from the toxic location and dilution with pore water from the control station; (b) diluting whole sediment from the toxic location with control whole sediment from a reference location, then extracting pore water; and (c) diluting toxic, whole sediment with whole sediment from a reference location, then using the whole sediment in bioassays. Based on lethality, H. limbata was the most sensitive organism to the toxicity of Detroit River sediment. Lethality of D. magna was similar to that of H. limbata in whole sediment and can be used to predict effects of whole sediment toxicity to H. limbata. The concentration required to cause a 50% reduction in C. tentans growth (10-d EC50) was approximately that which caused 50% lethality of D. magna (48-h LC50) and was similar to the toxicity that restricts benthic invertebrate colonization of contaminated sediments. While the three dilution techniques gave similar results with some assays, they gave very different results in other assays. The dose-response relationships determined by the three dilution techniques would be expected to vary with sediment, toxicant and bioassay type, and the dose-response relationship derived from each technique needs to be interpreted accordingly.

Giesy, John P.; Rosiu, Cornell J.; Graney, Robert L.; Henry, Mary G.

1990-01-01

56

Quantification of sediment-water interactions in a polluted tropical river through biogeochemical modeling  

NASA Astrophysics Data System (ADS)

Diagenetic modeling presents an interesting and robust way to understand sediment-water column processes. Here we present the application of such a model to the Day River in Northern Vietnam, a system that is subject to high levels of domestic wastewater inputs from the Hanoi metropolitan area. Experimental data from three areas of different water and sediment quality, combined with some additional data from the river, are used to set up and calibrate a diagenetic model. The model was used to determine the role of the sediments as a sink for carbon and nutrients and shows that in the dry season, 27% of nitrogen, 25% of carbon, and 38% of phosphorus inputs into the river system are stored in sediments. The corresponding numbers during the rainy season are 15%, 10%, and 20%, respectively. The diagenetic model was then used to test the impact of an improvement in the treatment of Hanoi's municipal wastewater. We show that improved wastewater treatment could reduce by about 17.5% the load of organic matter to the sediment. These results are the first to highlight the importance of sediments as a potential removal mechanism of organic matter and nutrients from the water column in this type of highly impacted tropical urban river, further demonstrating that rivers need to be considered as reaction sites and not just as inert conduits.

Trinh, Anh Duc; Meysman, Filip; Rochelle-Newall, Emma; Bonnet, Marie Paule

2012-09-01

57

Potential for release of sediment phosphorus to Lake Powell (Utah and Arizona) due to sediment resuspension during low water level  

Microsoft Academic Search

The water level in Lake Powell, an important water-supply reservoir on the Colorado River, United States, decreased in most years from 1999 to 2010, exposing the sediment delta in the inflow region of this reservoir. This study assesses the potential for sediment-associated phosphorus (P) to enter the water column during sediment resuspension. We collected sediment samples from the reservoir inflow

Richard A. Wildman Jr; Janet G. Hering

2011-01-01

58

NORTH PORTAL - DOMESTIC COLD WATER CALCULATION - CHANGE HOUSE FACILITY #5008  

SciTech Connect

The purpose of this design analysis and calculation is to determine the demand for domestic cold water and to size the supply main piping for the Change House Facility No.5008 in accordance with the Uniform Plumbing Code (Section 4.4.1) and U.S. Department of Energy Order 6430.1A-1540 (Section 4.4.2). The method used for the calculations is based on the Uniform Plumbing Code (UPC), Section 4.4.1. The first step is to determine the maximum pressure drop between the most remote cold water plumbing fixture and the main distribution supply. The developed length of pipe from the supply to the fixture is then determined from the plumbing drawings. The maximum pressure drop is then divided by the developed length which results in the friction loss per 100 feet of pipe. Equivalent fixture units are assigned from the UPC based on the actual fixture count which when totaled determines the water flow rate. The water flow rate and pressure drop are used to determine the pipe size based on a given velocity of flow.

R. Blackstone

1996-01-25

59

Sedimentation of helminth eggs in water.  

PubMed

Helminth parasite eggs in low quality water represent health risks when used for irrigation of crops. The settling velocities of helminth eggs (Ascaris suum, Trichuris suis, and Oesophagostomum spp.) and wastewater particles were experimentally determined in tap water and in wastewater using Owen tubes. The settling velocities of eggs in tap water was compared with theoretical settling velocities calculated by Stoke's law using measurements of size and density of eggs as well as density and viscosity of tap water. The mean settling velocity in tap water of 0.0612 mm s(-1) found for A. suum eggs was significantly lower than the corresponding values of 0.1487 mm s(-1) for T. suis and 0.1262 mm s(-1) for Oesophagostomum spp. eggs. For T. suis and Oesophagostomum spp. eggs the theoretical settling velocities were comparable with the observed velocities in the Owen tubes, while it was three times higher for A. suum eggs. In wastewater, the mean settling velocity for A. suum eggs (0.1582 mm s(-1)) was found to be different from T. suis (0.0870 mm s(-1)), Oesophagostomum spp. (0.1051 mm s(-1)), and wastewater particles (0.0474 mm s(-1)). This strongly indicates that in low quality water the eggs are incorporated into particle flocs with different settling velocities and that the settling velocity of eggs and particles is closely associated. Our results document that there is a need to differentiate the sedimentation of different types of helminth eggs when assessing the quality of low quality water, e.g. for irrigation usage. The results can also be used to improve existing models for helminth egg removal. PMID:21741063

Sengupta, Mita E; Thamsborg, Stig M; Andersen, Thorbjørn J; Olsen, Annette; Dalsgaard, Anders

2011-06-24

60

The geochemistry of uranium and thorium in coastal marine sediments and sediment pore waters  

Microsoft Academic Search

Pore water profiles of uranium and thorium isotopes in the muddy sediments of Buzzards Bay, MA permit an assessment of the effect of diagenetic redox reactions on the geochemical behavior of these elements. Uranium shows a pronounced minimum pore water concentration (~ 1.2 dpm\\/kg) near the sediment water interface (0-3 cm) which coincides with the pore water Fe maximum. U

J. Kirk Cochran; Anne E. Carey; Edward R. Sholkovitz; Lolita D. Surprenant

1986-01-01

61

Elemental composition in sediments and water in the Trancão river basin. A preliminary study  

NASA Astrophysics Data System (ADS)

The Trancão river basin, located in the Lisbon area shows preoccupying pollution levels, that constitute a threat to public health and the ecological system. This work reports on the results obtained in the analysis of surface sediments (EDXRF) and water (PIXE) collected in the wet and dry season during 1996. In general, bulk sediments and water show high concentration levels for some heavy metals like Cr, Cu, Zn and Pb. The elemental contents variation of samples collected at the different sites of the river basin were large, owing apparently to pollution sources, seasonal variabilities and grain size distribution (sediments). In the dry season, effluents (industrial and domestic) showed a stronger influence on the sediment composition. High levels of As and Br were found in the water that can be attributed to extended sources like sewage sludge and fertilizers. In some locations, the metals, Ca and organic matter enrichment could be associated with a paper mill and metal processing industry (high levels of Cr). At the estuary, the decrease of metal content determined in the sampled water indicates the flocculation of dissolved organic and inorganic materials. However, no effects were found for the surface sediment metal content, probably due to a dilution with materials from the Tagus inner estuary (the largest in Portugal).

Araújo, F.; Pinheiro, T.; Alves, L. C.; Valério, P.; Gaspar, F.; Alves, J.

1998-03-01

62

TOXICITY EVALUATION OF LOWER FOX RIVER WATER AND SEDIMENTS  

EPA Science Inventory

Many persistent, xenobiotic compounds have been identified from Lower Fox River water, biota, sediment, and effluent discharges; some of which are suspected of causing adverse effects to aquatic organisms. Water and sediment were collected as grab samples from the Lower Fox River...

63

Exchange of phosphorus across the sediment-water interface  

Microsoft Academic Search

In this article, principles of phosphorus retention and phosphorus release at the sediment-water interface in lakes are reviewed. New results and hypotheses are discussed in relation to older models of phosphorus exchange between sediments and water. The fractional composition of sedimentary phosphorus is discussed as a tool for interpretation of different retention mechanisms. Special emphasis is given to the impact

Bengt Boström; Jens M. Andersen; Siegfried Fleischer; Mats Jansson

1988-01-01

64

ON THE COMBINED EFFECT OF WASTEWATER HEAT RECOVERY AND SOLAR DOMESTIC HOT WATER HEATING  

Microsoft Academic Search

This article focuses on two methods of reducing the energy consumption associated with domestic hot water (DHW) heating in residences. The first method uses a gravity Film heat eXchanger (often referred to as a GFX or a PowerPipe) to recuperate part of the energy contained in the grey water coming from showers. The second method is a classic solar domestic

Daniel Picard; Véronique Delisle; Michel Bernier; Michaël Kummert

65

A truncated pyramid non-tracking type multipurpose domestic solar cooker\\/hot water system  

Microsoft Academic Search

For impressive dissemination of the solar thermal gazettes, it is imperative to keep on changing the device design features so as to cater to the different demands of diverse section of the society. Domestic solar hot water systems are not suitable for cooking and the capacity of domestic solar box type cookers for water heating is very low. We report

Naveen Kumar; Tilak Chavda; H. N. Mistry

2010-01-01

66

Mathematical Simulation of Sediment and Radionuclide Transport in Surface Waters  

SciTech Connect

The study objective of "The Mathematical Simulation of Sediment and Radionuclide Transport in Surface Waters" is to synthesize and test radionuclide transport models capable of realistically assessing radionuclide transport in various types of surface water bodies by including the sediment-radionuclide interactions. These interactions include radionuclide adsorption by sediment; desorption from sediment into water; and transport, deposition, and resuspension of sorbed radionuclides controlled by the sediment movements. During FY-1979, the modification of sediment and contaminant (radionuclide) transport model, FETRA, was completed to make it applicable to coastal waters. The model is an unsteady, two-dimensional (longitudinal and lateral) model that consists of three submodels (for sediment, dissolved-contaminant, and particulate-contaminant transport), coupled to include the sediment-contaminant interactions. In estuaries, flow phenomena and consequent sediment and radionuclide migration are often three-dimensional in nature mainly because of nonuniform channel cross-sections, salinity intrusion, and lateral-flow circulation. Thus, an unsteady, three-dimensional radionuclide transport model for estuaries is also being synthesized by combining and modifying a PNL unsteady hydrothermal model and FETRA. These two radionuclide transport models for coastal waters and estuaries will be applied to actual sites to examine the validity of the codes.

,

1981-04-01

67

30 CFR 77.216-4 - Water, sediment or slurry impoundments and impounding structures; reporting requirements...  

Code of Federal Regulations, 2010 CFR

...2009-07-01 false Water, sediment or slurry impoundments and impounding structures... § 77.216-4 Water, sediment or slurry impoundments and impounding structures...or controlling a water, sediment, or slurry impoundment and impounding...

2009-07-01

68

30 CFR 77.216-1 - Water, sediment or slurry impoundments and impounding structures; identification.  

Code of Federal Regulations, 2010 CFR

...2009-07-01 false Water, sediment or slurry impoundments and impounding structures... § 77.216-1 Water, sediment or slurry impoundments and impounding structures...immediately adjacent to each water, sediment or slurry impounding structure within the...

2009-07-01

69

30 CFR 77.216-1 - Water, sediment or slurry impoundments and impounding structures; identification.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Water, sediment or slurry impoundments and impounding structures... § 77.216-1 Water, sediment or slurry impoundments and impounding structures...immediately adjacent to each water, sediment or slurry impounding structure within the...

2013-07-01

70

30 CFR 77.216-3 - Water, sediment, or slurry impoundments and impounding structures; inspection requirements...  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Water, sediment, or slurry impoundments and impounding structures...77.216-3 Water, sediment, or slurry impoundments and impounding structures...requirements. (a) All water, sediment, or slurry impoundments that meet the...

2013-07-01

71

30 CFR 77.216-4 - Water, sediment or slurry impoundments and impounding structures; reporting requirements...  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Water, sediment or slurry impoundments and impounding structures... § 77.216-4 Water, sediment or slurry impoundments and impounding structures...or controlling a water, sediment, or slurry impoundment and impounding...

2013-07-01

72

30 CFR 77.216-1 - Water, sediment or slurry impoundments and impounding structures; identification.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 false Water, sediment or slurry impoundments and impounding structures... § 77.216-1 Water, sediment or slurry impoundments and impounding structures...immediately adjacent to each water, sediment or slurry impounding structure within the...

2010-07-01

73

30 CFR 77.216-3 - Water, sediment, or slurry impoundments and impounding structures; inspection requirements...  

Code of Federal Regulations, 2010 CFR

...2010-07-01 false Water, sediment, or slurry impoundments and impounding structures...77.216-3 Water, sediment, or slurry impoundments and impounding structures...requirements. (a) All water, sediment, or slurry impoundments that meet the...

2010-07-01

74

30 CFR 77.216-5 - Water, sediment or slurry impoundments and impounding structures; abandonment.  

Code of Federal Regulations, 2010 CFR

...2009-07-01 false Water, sediment or slurry impoundments and impounding structures... § 77.216-5 Water, sediment or slurry impoundments and impounding structures...abandonment of any water, sediment, or slurry impoundment and impounding...

2009-07-01

75

30 CFR 77.216-4 - Water, sediment or slurry impoundments and impounding structures; reporting requirements...  

Code of Federal Regulations, 2010 CFR

...2010-07-01 false Water, sediment or slurry impoundments and impounding structures... § 77.216-4 Water, sediment or slurry impoundments and impounding structures...or controlling a water, sediment, or slurry impoundment and impounding...

2010-07-01

76

Solar domestic hot water technology evaluation program. Final report  

SciTech Connect

The Florida Solar Energy Center, under contract to the New York State Energy Research and Development Authority (NYSERDA), installed 12 solar domestic hot water (SDHW) systems in single-family residences in downstate New York and instrumented them to determine energy consumption and time-of-day electrical demand. Annual performance data was collected on both the SDHW systems and the original electric resistance water heaters and has been analyzed to determine energy efficiency, cost effectiveness, and the impact on electrical utility peak demand. The average New York SDHW system installed during this program operated with approximately 63 percent higher annual electrical energy efficiency than the average electric resistance water heater. The energy savings for the twelve New York SDHW systems ranged from approximately 900 to 3,100 kWh per year, with a mean of 1,980 kWh per year. Hence, at the 1995 residential electricity rates of LILCO, Con Edison, and Orange and Rockland Utilities, the average utility customer could save approximately $325 per year due to a typical SDHW system. The average installed cost for a SDHW system in this program was $3,850, so the average tax-free rate of return for the 12 SDHW systems was 8.4 percent. However if the utility owned the SDHW system and sold the hot water to the customer for a monthly fee, the after-tax internal rate of return to the utility could be higher than the customer`s rate of return, because of the utility`s ability to take depreciation and the federal solar energy investment tax credit.

NONE

1998-07-01

77

Design of multifamily solar domestic hot water systems using recirculating distribution  

SciTech Connect

This paper describes a study designed to quantify the effect of daily domestic hot water loads and system design on the performance of solar domestic hot water systems employing a recirculating distribution system. A solar domestic hot water system judged representative of the systems funded by the HUD Solar Demonstration Program, along with a modification to this system, was modeled using the TRNSYS simulation computer program. Results of simulations over a representative climatic period show that daily domestic hot water usage significantly affects solar system performance. Notable improvement in system performance can be obtained by the use of a recirculation return to solar storage system configuration within a specific range of daily domestic hot water loads. An optimum system was developed from parametric variations of system design and modeled on an annual basis. Comparison is made to modeled system performance of the original design.

Wedekind, D.R.

1982-01-01

78

Degradation of rizazole in water-sediment systems.  

PubMed

This study investigated the degradation of rizazole in water-sediment systems (West Lake system, WL; Beijing-Hangzhou Grand Canal system, BG) with two different types of sediments under aerobic and anaerobic conditions. The half-lives of rizazole in the WL water phase (14.59-15.13 d) were similar to those in the BG water phase (15.90-16.46 d). Within 3-7 d, the rizazole concentration in the sediments reached the maximum values, i.e., equilibrium. Rizazole dissipation was faster in the WL sediment phase with higher organic matter content (T(1/2) = 18.99-19.09 d) compared with the BG sediment phase (T(1/2) = 31.08-33.32 d). Rizazole degradation was slightly faster in the West Lake water-sediment system (WL system) (T(1/2) = 17.11-18.05 d) than in the Beijing-Hangzhou Grand Canal water-sediment system (BG system) (T(1/2) = 20.51-25.02 d). The aerobic degradation of rizazole was similar to its anaerobic degradation in the water-sediment system. The findings are useful to understand the behavior of pesticide in environment. PMID:23431969

Zhang, Changpeng; Zhao, Hua; Ping, Lifeng; Cai, Xiaoming; Wu, Min; He, Hongmei; Zhang, Chunrong; Zhu, Yahong; Li, Zhen

2013-01-01

79

Measurement of Mercury Methylation in Lake Water and Sediment Samples  

PubMed Central

Biological mercury methylation was assayed by a new radiochemical technique in the water column and sediments of a mercury-contaminated lake. In 24 weeks during 1979, there were three episodes of methylating activity in surface floc and in water, each lasting 3 to 5 weeks. Periods of methylation in the water column coincided with surface sediment methylation and appeared to be related to overall microbial activity. Mercury was actively methylated in the presence of bound sulfide.

Furutani, Akira; Rudd, John W. M.

1980-01-01

80

Sediment-Water Fluxes and Sediment Analyses in Chesapeake Bay: Tidal Fresh Potomac River and Maryland Main Stem.  

National Technical Information Service (NTIS)

The report describes sediment-water flux measurements and associated observations in the water column and benthic sediments. Observations were conducted at four stations in the tidal Potomac River and adjoining Chesapeake Bay from May through October 1994...

W. R. Boynton J. M. Barnes B. J. Weaver L. L. Magdeburger P. Sampou

1996-01-01

81

Comparing Sediment and Pore-water Measurements as Predictors of PCB Uptake by Oligochaetes from Sediments  

EPA Science Inventory

There is an increasing amount of chemical and biological evidence that using sediment concentrations and commonly applied Koc values frequently overpredicts interstitial water concentrations of HOCs, and thereby overestimates uptake and/or effects of those chemicals on exposed or...

82

Sediment pore water distribution coefficients of PCB congeners in enriched black carbon sediment.  

PubMed

More than 2300 sediment pore water distribution coefficients (KPCBi ds) of 93 polychlorinated biphenyls (PCBs) were measured and modeled from sediments from Indiana Harbor and Ship Canal. KPCBi ds were calculated from previously reported bulk sediment values and newly analyzed pore water. PCBs in pore waters were measured using SPME PDMS-fiber and ?PCB ranged from 41 to 1500 ng L(-1). The resulting KPCBi ds were ?1 log unit lower in comparison to other reported values. A simple model for the KPCBi d consisted of the product of the organic carbon fraction and the octanol-water partition coefficient and provided an excellent prediction for the measured values, with a mean square error of 0.09 ± 0.06. Although black carbon content is very high in these sediments and was expected to play an important role in the distribution of PCBs, no improvement was obtained when a two-carbon model was used. PMID:23974165

Martinez, Andres; O'Sullivan, Colin; Reible, Danny; Hornbuckle, Keri C

2013-08-23

83

Promising freeze protection alternatives in solar domestic hot water systems  

SciTech Connect

Since the gains associated with solar thermal energy technologies are comparatively small in relation to the required capital investment, it is vital to maximize conversion efficiency. While providing the necessary function of freeze protection, the heat exchanger commonly included in solar domestic water heating systems represents a system inefficiency. This thesis explores two alternate methods of providing freeze protection without resorting to a heat exchanger. Commonly, collectors are made of rigid copper tubes separated by copper or aluminum fins. Cracking damage can occur when water is allowed to freeze and expand inside the non compliant tubes. The possibility of making collectors out of an elastic material was investigated and shown to be effective. Since unlike copper, elastomers typically have low thermal conductivities, the standard collector performance prediction equations do not apply. Modified thermal performance prediction equations were developed which can be used for both low and high thermal conductivity materials to provide accurate predictions within a limited range of plate geometries. An elastomeric collector plate was then designed and shown to have comparable performance to a copper plate collector whose aperture area is approximately 33% smaller. Another options for providing freeze protection to an SDHW system is to turn it off during the winter. Choosing a three-season operating period means two things. First, the system will have different optimums such as slope and collector area. Second, the wintertime solar energy incident on the collector is unavailable for meeting a heating load. However, the system`s heat exchanger becomes unnecessary and removing it increases the amount of energy that arrives at the storage tank during those periods in which the system is operating.

Bradley, D.E.

1997-12-31

84

DISTRIBUTION OF ORGANIC WASTEWATER CONTAMINANTS BETWEEN WATER AND SEDIMENT IN SURFACE WATERS OF THE UNITED STATES  

EPA Science Inventory

Trace concentrations of pharmaceuticals and other organic wastewater contaminants have been determined in the surface waters of Europe and the United States. A preliminary report of substantially higher concentrations of pharmaceuticals in sediment suggests that bottom sediment ...

85

Determination of Metallic Elements in Interstitial Waters of Aquatic Sediments.  

National Technical Information Service (NTIS)

Results are given for the determination of Mn, Sr, Ni, Fe, Cu, and Sb concentrations in interstitial waters extracted from marine sediments from the Gulf of Spezia and from lake sediments of the Massaciuccoli Lake and the Torre del Lago. Tabulated data ar...

R. Boniforti M. Cambiaghi P. Frigieri

1980-01-01

86

Toxicity of silicon carbide nanowires to sediment-dwelling invertebrates in water or sediment exposures.  

PubMed

Silicon carbide nanowires (SiCNW) are insoluble in water. When released into an aquatic environment, SiCNW would likely accumulate in sediment. The objective of this study was to assess the toxicity of SiCNW to four freshwater sediment-dwelling organisms: amphipods (Hyalella azteca), midges (Chironomus dilutus), oligochaetes (Lumbriculus variegatus), and mussels (Lampsilis siliquoidea). Amphipods were exposed to either sonicated or nonsonicated SiCNW in water (1.0?g/L) for 48?h. Midges, mussels, and oligochaetes were exposed only to sonicated SiCNW in water for 96?h. In addition, amphipods were exposed to sonicated SiCNW in whole sediment for 10 d (44% SiCNW on dry wt basis). Mean 48-h survival of amphipods exposed to nonsonicated SiCNW in water was not significantly different from the control, whereas mean survival of amphipods exposed to sonicated SiCNW in two 48-h exposures (0 or 15% survival) was significantly different from the control (90 or 98% survival). In contrast, no effect of sonicated SiCNW was observed on survival of midges, mussels, or oligochaetes. Survival of amphipods was not significantly reduced in 10-d exposures to sonicated SiCNW either mixed in the sediment or layered on the sediment surface. However, significant reduction in amphipod biomass was observed with the SiCNW either mixed in sediment or layered on the sediment surface, and the reduction was more pronounced for SiCNW layered on the sediment. These results indicated that, under the experimental conditions, nonsonicated SiCNW in water were not acutely toxic to amphipods, sonicated SiCNW in water were acutely toxic to the amphipods, but not to other organisms tested, and sonicated SiCNW in sediment affected the growth but not the survival of amphipods. PMID:21305577

Mwangi, Joseph N; Wang, Ning; Ritts, Andrew; Kunz, James L; Ingersoll, Christopher G; Li, Hao; Deng, Baolin

2011-02-08

87

Sediment mediated species interactions in coastal waters  

Microsoft Academic Search

Self-structuring in marine sediment communities is achieved by the mobility of the organisms, the trophic web, and biogenic transformations of the habitat. The latter are: bioconstruction and bioturbations, sediment stabilisation and destabilisation, with facilitating and inhibiting effects. This cursory overview intends to show that in near-shore mud and sand, biogenic habitat transformations pervade all community interactions. Consequently these deserve as

Karsten Reise

2002-01-01

88

Risk assessment of oxytetracycline in water phase to major sediment bacterial community: a water-sediment microcosm study.  

PubMed

With an increasing need for assessing the risk of aquaculture antibiotics, there has been growing interest in their fate and effect on sedimentary bacteria. Here we show the risk assessment for oxytetracycline (OTC) use in seawater and its subsequent transfer to sediment, and illustrate that the sediment bacterial community was stable against OTC at dosed concentrations. Water-sediment microcosm experiments were conducted to simulate quiescent aquaculture conditions. The sorption coefficient (Kd) was 12.3-44.2mL/g, which is lower than the previous reports employing vigorous mixing. In a denaturing gradient gel electrophoresis (DGGE) analysis, the addition of OTC at 50?g/L into the water phase had little effect on the major sediment bacterial community structure. This finding suggests that low concentrations of OTC in the water phase - such as those used within many aquaculture operations - do not pose a high risk of causing major changes in environmental sediment bacterial community structures. PMID:23619519

Suga, Natsumi; Ogo, Mitsuko; Suzuki, Satoru

2013-04-01

89

Impact of storm-water outfalls on sediment quality in Corpus Christi Bay, Texas, USA  

SciTech Connect

To determine the quality of sediments and extent of contaminant impacts, a Sediment Quality Triad (SQT) study was conducted at 36 sites in the Corpus Christi Bay, Texas, USA, system. Fifteen of the 36 sites were located near storm-water outfalls, but 13 other sites (i.e., industrial and domestic outfalls, oil field-produced water discharges, and dredging activity) and eight reference sites were also evaluated. Sediment samples were collected and analyzed for physical-chemical characteristics, contaminant concentrations (metals, polycyclic aromatic hydrocarbons [PAHs], polychlorinated biphenyls [PCBs], and pesticides), toxicity, and a benthic index of biotic integrity (BIBI) composed of 10 independent metrics calculated for each site. This large data matrix was reduced using multivariate analysis to create new variables for each component representing overall means and containing most of the variance in the larger data set. The new variables were used to conduct the correlation analysis. Toxicity was significantly correlated with both chemistry and ecological responses, whereas no correlations between the benthic metrics and sediment chemistry were observed. Using the combined information from the SQT, four of the five most degraded sites were storm-water outfall sites. Although estuaries are naturally stressful environments because of salinity and temperature fluctuations, this ecosystem appears to have been compromised by anthropogenic influences similar to what has been observed for other heavily urbanized bay systems along the Texas and Gulf coast.

Carr, R.S.; Montagna, P.A.; Biedenbach, J.M.; Kalke, R.; Kennicutt, M.C.; Hooten, R.; Cripe, G.

2000-03-01

90

The impact of urbanization on water and sediment chemistry of ...  

Treesearch

Source: Journal of Freshwater Ecology. ... The sediments of the urban pools were contaminated with elevated levels of barium, chromium, and lead. The water of the urban pools had higher pH, conductivity, and alkalinity and less dissolved ...

91

Residual nonclathrated water in sediments in equilibrium with gas hydrate  

Microsoft Academic Search

The method for experimental study of equilibrium for “pore water in sediment–hydrate-forming gas–bulk gas hydrate” system was developed at temperatures below and above 0°C, and at different pressures. The gas pressure may be above the pressure for the three-phase equilibrium for “ice–gas–bulk gas hydrate.” The method is based on measuring the equilibrium water content in an initially air-dried sediment plate

E. M. Chuvilin; V. A. Istomin; S. S. Safonov

2011-01-01

92

Degradation of sulfonamides antibiotics in lake water and sediment.  

PubMed

Degradation of three sulfonamides (SAs), namely sulfamethoxazole (SMX), sulfamethazine (SMZ), and sulfadimethoxine (SDM) in surface water and sediments collected from Taihu Lake and Dianchi Lake, China was investigated in this study. The surface water (5-10 cm) was collected from the east region of Taihu Lake, China. Two sets of degradation experiments were conducted in 3-L glass bottles containing 2 L of fresh lake water and 100 ?g/L of individual SAs aerated by bubbling air at a rate of approximately 1.2 L/min, one of which was sterilized by the addition of NaN3 (0.1%). Sediment samples were taken from Taihu Lake and Dianchi Lake, China. For the sediment experiment, 5 g of sediment were weighed into a 50-mL glass tube, with 10 mg/kg of individual SAs. Different experimental conditions including the sediment types, sterilization, light exposure, and redox condition were also considered in the experiments. The three SAs degraded in lake water with half-lives (t 1/2) of 10.5-12.9 days, and the half-lives increased significantly to 31.9-49.8 days in the sterilized water. SMZ and SDM were degraded by abiotic processes in Taihu and Dianchi sediments, and the different experimental conditions and sediments characteristics had no significant effect on their declines. SMX, however, was mainly transformed by facultative anaerobes in Taihu and Dianchi sediments under anaerobic conditions, and the degradation rate of SMX in non-sterile sediment (t 1/2 of 9.6-16.7 days) were higher than in sterilized sediment (t 1/2 of 18.7-135.9 days). Under abiotic conditions, degradation of SMX in Dianchi sediment was faster than in Taihu sediment, probably due to the higher organic matter content and inorganic photosensitizers concentrations in Dianchi sediment. High initial SAs concentration inhibited the SAs degradation, which was likely related to the inhibition of microorganism activities by high SAs levels in sediments. Results from this study could provide information on the persistence of commonly used sulfanomides antibiotics in lake environment. PMID:22903812

Zhang, Yuan; Xu, Jian; Zhong, Zhenxing; Guo, Changsheng; Li, Lei; He, Yan; Fan, Wenhong; Chen, Yucheng

2012-08-19

93

Fugacity approach to evaluate the sediment-water diffusion of polycyclic aromatic hydrocarbons.  

PubMed

Diffusion is an important process for sediment-water exchange and plays a vital role in controlling water quality. Fugacity fraction (ff) was used to estimate the sediment-water diffusion of polycyclic aromatic hydrocarbons (PAHs) between seawater and surficial sediment. A total of 33 surface sediment and sea water samples were collected concurrently from the northeast coastal area in China and 25 PAHs were analyzed including the alkylated and chlorated PAHs. Fugacity fraction was calculated based on the PAH concentrations in water and sediment, octanol-water partition coefficient of PAHs, organic matter content in sediment, and density of sediment. The calculated results showed that ff increased with decreasing molecular weight of PAHs. The low molecular weight PAHs (2-3 rings) transferred from sediment to water and the sediment acted as a secondary source to the water. The medium molecular weight PAHs (4-5 rings) were close to the sediment-water equilibrium and the transfer tendency shifted between sediment and water. The high molecular weight PAHs (5-6 rings) transferred from water into sediment and the sediment acted as a sink. Soot carbon and the difference of PAH concentrations between sediment and water were found to be important factors affecting the sediment-water diffusion. This study provided new insight into the process of sediment-water diffusion, which has a great influence on the quality of water, especially in severely-polluted sediment areas. PMID:21552633

Wang, De-Gao; Alaee, Mehran; Byer, Jonathan; Liu, Yong-Jun; Tian, Chong-Guo

2011-05-09

94

Microbiological Evaluation of Water Quality from Urban Watersheds for Domestic Water Supply Improvement  

PubMed Central

Agricultural and urban runoffs may be major sources of pollution of water bodies and major sources of bacteria affecting the quality of drinking water. Of the different pathways by which bacterial pathogens can enter drinking water, this one has received little attention to date; that is, because soils are often considered to be near perfect filters for the transport of bacterial pathogens through the subsoil to groundwater. The goals of this study were to determine the distribution, diversity, and antimicrobial resistance of pathogenic Escherichia coli isolates from low flowing river water and sediment with inputs from different sources before water is discharged into ground water and to compare microbial contamination in water and sediment at different sampling sites. Water and sediment samples were collected from 19 locations throughout the watershed for the isolation of pathogenic E. coli. Heterotrophic plate counts and E. coli were also determined after running tertiary treated water through two tanks containing aquifer sand material. Presumptive pathogenic E. coli isolates were obtained and characterized for virulent factors and antimicrobial resistance. None of the isolates was confirmed as Shiga toxin E. coli (STEC), but as others, such as enterotoxigenic E. coli (ETEC). Pulsed field gel electrophoresis (PFGE) was used to show the diversity E. coli populations from different sources throughout the watershed. Seventy six percent of the isolates from urban sources exhibited resistance to more than one antimicrobial agent. A subsequent filtration experiment after water has gone through filtration tanks containing aquifer sand material showed that there was a 1 to 2 log reduction in E. coli in aquifer sand tank. Our data showed multiple strains of E. coli without virulence attributes, but with high distribution of resistant phenotypes. Therefore, the occurrence of E. coli with multiple resistances in the environment is a matter of great concern due to possible transfer of resistant genes from nonpathogenic to pathogenic strains that may result in increased duration and severity of morbidity.

Ibekwe, A. Mark; Murinda, Shelton E.; Graves, Alexandria K.

2011-01-01

95

The geochemistry of uranium and thorium in coastal marine sediments and sediment pore waters  

NASA Astrophysics Data System (ADS)

Pore water profiles of uranium and thorium isotopes in the muddy sediments of Buzzards Bay, MA permit an assessment of the effect of diagenetic redox reactions on the geochemical behavior of these elements. Uranium shows a pronounced minimum pore water concentration (~ 1.2 dpm/kg) near the sediment water interface (0-3 cm) which coincides with the pore water Fe maximum. U concentrations increase with depth to a broad maximum which is greater than the overlying seawater value, then decrease. Laboratory sediment tank experiments maintained without macrofauna also show the near-interface minimum and increase, and sediment incubation experiments show removal of U from the pore water to a constant value by about 40 days. The 234U /238U activity ratio is equal to the seawater value in all samples. Oxidation state separations of pore water U in HCl solution (using anion exchange) demonstrate that U is present in the pore water as U(VI). The coincidence of the pore water uranium and Fe maximum is consistent with the hypothesis of reduction of U(VI) to U(IV) and removal from solution at about the same depth (or pe) as Fe is reduced. Increases in pore water U with depth appear to be related to release of authigenic (seawater) U(VI) to solution, possibly as alkalinity and pH increase and organic matter with which the U is associated is oxidized. Lower concentrations at depth in the sediment column may be linked to increases of effective U reducing agents like hydrogen sulfide in the pore water or to the activities of macrofauna. In contrast, pore water profiles of the long-lived Th isotopes 232Th and 230Th show low activities (? .02 dpm/kg) and relatively little change with depth, although values are greater than those in the overlying water. Solid phase activities are similarly constant with depth, and the distribution may be controlled by a sorption equilibrium between pore water and the solid phase. The short-lived isotope 234Th shows greatest pore water activities in the upper 5 cm and is present at virtually zero activities elsewhere in the sediment column. The upper few centimeters of the sediment generally contain excess 234Th scavenged from the overlying water column and distributed by bioturbation, as well as pore water Fe and Mn profiles which show maxima indicating reduction and dissolution of Fe and Mn oxyhydroxides. The pore water 234Th profile can be explained by release of 234Th from the solid phase as Fe/Mn oxide surface coatings are reduced and dissolved.

Cochran, J. Kirk; Carey, Anne E.; Sholkovitz, Edward R.; Surprenant, Lolita D.

1986-05-01

96

European Modelling Group for SHS (Solar Heating Systems) and DHW (Domestic Hot Water).  

National Technical Information Service (NTIS)

The report describes the contribution of the German participant, the Fraunhofer-Institut fur Systemtechnik and Innovationsforschung, of the European Modelling Group for Solar Heating Systems and Domestic Hot Water in the years 1980 and 1981. The main purp...

J. Reichert D. Schlag H. Herz

1984-01-01

97

Water quality in a rural river environment: distribution of metals among water and sediment compartments  

Microsoft Academic Search

Sediments have a significant influence on water quality, owing to their role both as a sink and a potential source of pollutants. In fluvial environments from mountainous catchments, the dynamics of sediment particles and particle-bound contaminants are still poorly understood. As stated by Symader et al. (2007), bottom sediments of small rivers in mountainous areas behave like a transport system

A. Reis; A. Parker; A. Alencoao

2009-01-01

98

Pore Water Transport of Enterococci out of Beach Sediments  

PubMed Central

Enterococci are used to evaluate the safety of beach waters and studies have identified beach sands as a source of these bacteria. In order to study and quantify the release of microbes from beach sediments, flow column systems were built to evaluate flow of pore water out of beach sediments. Results show a peak in enterococci (average of 10% of the total microbes in core) released from the sand core within one pore water volume followed by a marked decline to below detection. These results indicate that few enterococci are easily removed and that factors other than simple pore water flow control the release of the majority of enterococci within beach sediments. A significantly larger quantity and release of enterococci were observed in cores collected after a significant rain event suggesting the influx of fresh water can alter the release pattern as compared to cores with no antecedent rainfall.

Phillips, Matthew C.; Solo-Gabriele, Helena M.; Reniers, Adrianus J. H. M.; Wang, John D.; Kiger, Russell T.; Abdel-Mottaleb, Noha

2011-01-01

99

Pore water transport of enterococci out of beach sediments.  

PubMed

Enterococci are used to evaluate the safety of beach waters and studies have identified beach sands as a source of these bacteria. In order to study and quantify the release of microbes from beach sediments, flow column systems were built to evaluate flow of pore water out of beach sediments. Results show a peak in enterococci (average of 10% of the total microbes in core) released from the sand core within one pore water volume followed by a marked decline to below detection. These results indicate that few enterococci are easily removed and that factors other than simple pore water flow control the release of the majority of enterococci within beach sediments. A significantly larger quantity and release of enterococci were observed in cores collected after a significant rain event suggesting the influx of fresh water can alter the release pattern as compared to cores with no antecedent rainfall. PMID:21945015

Phillips, Matthew C; Solo-Gabriele, Helena M; Reniers, A J H M; Wang, John D; Kiger, Russell T; Abdel-Mottaleb, Noha

2011-09-25

100

Sediments and Sediment-Water Nutrient Interchange in Upper Klamath Lake, Oregon.  

National Technical Information Service (NTIS)

Upper Klamath Lake, a very large, shallow lake in south-central Oregon, has a history of nuisance blue-green algae blooms, predominantly Aphanizomenon flos-aquae. Lake water and sediment interstitial water chemistry were monitored during 1968 and 1969, an...

W. D. Sanville C. F. Powers A. R. Gahler

1974-01-01

101

Reuse feasibility of pre-treated grey water and domestic wastewater with a compact household reverse osmosis system  

Microsoft Academic Search

Many countries in the Mediterranean basin are facing water shortage issues. Since water is becoming a rare resource, grey water and domestic wastewater reuse arises as a sustainable solution to reduce the overall water demand. In this study, a compact household reverse osmosis unit was used in order to determine the feasibility of pre-treated grey water and domestic wastewater reuse.

G. Onkal Engin; B. Sinmaz Ucar; E. Senturk

2011-01-01

102

Subglacial sediment mobilization and accretion via supercooled water  

NASA Astrophysics Data System (ADS)

A growing literature describes the observations and potential implications of subglacial supercooling. Accreted ice and emerging water from Matanuska Glacier, Alaska, inspire many of the interpretations associated with this literature. Much of the excitement revolves around the ability of supercooling to entrain bed material. A younger package of sediment-rich accreted basal ice underlays older meteoric glacier ice. This superposition suggests that the process may operate beneath the hydraulically-active lobes of former ice sheets. Yet data are sparse, and insight from a mathematical perspective has been limited. We use the formalism of the Spring--Hutter equations to illuminate the individual governing mechanisms and magnitudes associated with subglacial water flow. This formalism is time-dependent and allows for investigation of various geometries. In addition, we employ an empirical set of rules for sediment transport by the flowing water and incorporation into the superjacent ice. Transported sediment is entrained into the overlying ice via the phase change. Results indicate that the supercooled water has the ability to move much sediment. However, the calibre of the sediment is limited by ice--bed aperture and not necessarily by the size of sediment available for transport.

Creyts, T. T.; Clarke, G. K.

2004-05-01

103

Antifouling biocides in water and sediments from California marinas.  

PubMed

Irgarol 1051 is a common antifouling biocide and is highly toxic to non-target plant species at low ng/L concentrations. We measured up to 254 ng/L Irgarol in water and up to 9 ng/g dry weight Irgarol in sediments from Southern California recreational marinas. Irgarol's metabolite, M1, concentrations were up to 62 ng/L in water and 5 ng/g dry weight in sediments. Another antifouling biocide, diuron, reached up to 68 ng/L in water and 4 ng/g dry weight in sediments. The maximum Irgarol concentrations in water were greater than the Irgarol concentration recommended as the plant toxicity benchmark (136 ng/L), suggesting that Irgarol concentrations may be high enough to cause changes in phytoplankton communities in the sampled marinas. Irgarol concentrations measured in sediments were greater than calculated Environmental Risk Limits (ERLs) for Irgarol in sediments (1.4 ng/g). Antifouling pesticide accumulation in sediments may present a potential undetermined risk for benthic organisms. PMID:23453818

Sapozhnikova, Yelena; Wirth, Edward; Schiff, Kenneth; Fulton, Michael

2013-02-28

104

Water and suspended sediment division at a stratified tidal junction  

NASA Astrophysics Data System (ADS)

Tidal junctions play a crucial role in the transport of water, salt, and sediment through a delta distributary network. Water, salt and sediment are exchanged at tidal junctions, thereby influencing the transports in the connecting branches and the overall dynamics of the system. This paper presents observations of water, salt and sediment transports in three channels that connect at a stratified tidal junction. Flow variation in one channel was found to lag behind flow variation in a connected channel by more than 1 h, which is largely attributed to channel length differences from the junction to the sea. The water columns in the three channels were periodically stratified during spring tide, whereas the salinity structure represented a salt wedge during neap tide. Salinity differences between the three channels were substantial. The channels contain water bodies of different salinity and act largely independently. Flow velocities in the upper and lower layers differed substantially. Flow in the lower layer was generally in the direction of acceleration produced by the baroclinic pressure gradient. Interestingly, baroclinic pressure gradients were sometimes directed landward, indicating the presence of saltier water at the land side of the estuary. In sharp channel bends close to the junction, secondary flow was strongest at the highest axial flow velocity during spring tide. In one channel bend, these circulations steered the suspended sediment toward the inner bend, which affected the suspended sediment division.

Buschman, F. A.; Vegt, M.; Hoitink, A. J. F.; Hoekstra, P.

2013-03-01

105

Factors affecting pore water hydrocarbon concentrations in Puget Sound sediments  

SciTech Connect

Polycyclic aromatic hydrocarbon (PAH) and aliphatic hydrocarbon concentrations have been determined for sediments and associated pore waters collected at 2 sites (11 stations) in Puget Sound, Washington (northwest U.S.A.). These sediments have been contaminated to varying degrees by hydrocarbons from a creosote plant and from various combustion sources. PAH were not detected in pore waters of sediments whose PAH were primarily derived from combustion and natural sources, even though pore water concentrations predicted from sediment concentrations and two-phase equilibrium partitioning models were above detection limits from most PAH. Equilibrium partition coefficients calculated from field aqueous and solid phase data from an area contaminated with creosote agreed with laboratory-derived coefficients to within a factor of +/- 4. Pore water concentrations of creosote-derived aliphatic hydrocarbons increase with increasing concentration in bulk sediments. However, pore water concentrations of natural and contaminant aliphatic hydrocarbons are much higher than predicted by solubility data, possible due to association with nonfilterable dissolved organic matter and colloids. Other major factors controlling hydrocarbon pore water concentrations include differential hydrocarbon sources, specific particle associations and solubility.

Socha, S.B.; Carpenter, R.

1987-05-01

106

Decision-Support System for Domestic Water Demand Forecasting and Management  

Microsoft Academic Search

A decision support system (DFMS) for forecastingdomestic water demand including demand management was developedas part of a highly integrated decision-support system forriver-basin management. The system provides water resourcesplanners with the facilities for estimating future water demandfor domestic use for any demand region and time period, havingregard, to the possibility of introducing demand managementmeasures. The system has the capability of predicting

M. Luay Froukh

2001-01-01

107

Sediment tracers in water erosion studies: Current approaches and challenges  

NASA Astrophysics Data System (ADS)

The quest for alternative methods of soil losses assessment, due to water erosion to complement and enhance existing methods has directed attention to the use of tracing approaches because of the additional information they provide, such as sediment source identification, tracking of sediment movement across the landscape at various temporal and spatial scales and soil erosion rates. For these reasons, the utility and robustness of sediment tracing approaches using a wide range of substances and soil properties have been evaluated in numerous studies. A comprehensive literature review on tracing approaches used in water erosion studies was carried out in June 2011 using the Web of Science database and as search terms in the title or as keywords: "erosion AND tracer" OR "sediment AND tracer" OR "sediment AND tracking". The search excluded reviews and tillage and/or wind erosion studies. Only studies that used tracers to make a determination of water erosion or sedimentation rates, or in some cases relative erosion contribution, were considered in this study, and were further refined by manually checking that the articles corresponded to experiments involving sediment studies using tracers, as defined within the context of this review. Five distinct groups of tracing approaches were identified: fallout radionuclides, rare earth elements, soil magnetism and magnetic substances, other tracers, and sediment fingerprinting techniques. This abstract presents a synthesis of the current approaches of each of the tracing techniques identified in assessing soil erosion and sediment redistribution and a summary with the commonalities and differences between the approaches and identifying research gaps and future trends.

Guzmán, Gema; Quinton, John N.; Nearing, Mark A.; Mabit, Lionel; Giráldez, Juan V.; Gómez, José A.

2013-04-01

108

Nitrogen cycling in different types of sediments from Danish waters  

Microsoft Academic Search

Variations in sediment N:C ratios were correlated with water depth and season. ¹⁴NHâ\\/sup +\\/ was used to measure the rates of NHâ\\/sup +\\/ production (d) and incorporation into bacterial cells (i) in sediments from different stations, at different seasons. The validity of the rates d and i was indicated by the predicted correlation of d:i ratios with N:C ratios of

T. H. Blackburn; K. Henridsen

1983-01-01

109

Assessing and managing sediment contamination in transitional waters.  

PubMed

Sediment contamination remains a global problem, particularly in transitional waters such as estuaries and coastal lagoons, which are the recipients of chemicals from multiple near- and far-field sources. Although transitional waters are highly productive ecosystems, approaches for assessing and managing their sediment contamination are not as well developed as in marine and fresh waters. Further, although transitional waters remain defined by their variable and unique natural water quality characteristics, particularly salinity, the biota inhabiting such ecosystems, once thought to be defined by Remane's "paradox of brackish water", are being redefined. The purpose of the present paper is to build on an earlier but now dated (>12years old) review of methods to assess sediment contamination in estuaries, extending this to all transitional waters, including information on integrative assessments and on management decision-making. The following are specifically discussed: chemical assessments; bioindicators; biomarkers; and, biological surveys. Assessment and management of sediment contamination in transitional waters need to be focused on ecosystem services and, where appropriate and possible, be proactive rather than reactive when uncertainty has been suitably reduced. PMID:23528483

Chapman, Peter M; Wang, Feiyue; Caeiro, Sandra Sofia

2013-03-22

110

Cobalt in pore waters of marine sediments  

Microsoft Academic Search

During early diagenesis on the sea floor, metal-recycling processes exert important controls on the preservation rates and distributions of metals in marine sediments. The elucidation of internal recycling processes, therefore, is important in understanding trace-metal mass balances in the oceans. Recent measurements of cobalt in seawater1 suggest that cobalt is scavenged from the deep sea and hence follows biogeochemical pathways

David Heggie; Tim Lewis

1984-01-01

111

Water Uptake by Roots Controls Water Table Movement and Sediment Oxidation in Short Spartina Marsh  

NASA Astrophysics Data System (ADS)

Downward movement of the water table during both day and night in the short grass zone of intertidal salt marshes is due not to drainage but to water uptake by roots. Removal of water from the sediment results in the entry of air into the sediment, suggesting a feedback between plant growth, water uptake, and sediment oxidation. The water balance of Spartina alterniflora appears to influence the internal morphology of its roots, potentially giving rise to a new mechanism for the mass flow of gas in plants.

Dacey, John W. H.; Howes, Brian L.

1984-05-01

112

The effectiveness of a magnetic physical water treatment device on scaling in domestic hot-water storage tanks  

Microsoft Academic Search

In this paper the effectiveness of a permanent magnet for the prevention of scale was investigated. Experiments were conducted on two electrically heated domestic hot-water storage tanks. Ten experiments were conducted, each over a period of 28 d in which 8 000 l of water was heated to 75°C, while the quality of the feed water and mass precipitation of

C Smith; PP Coetzee

113

Fluorescent dissolved organic matter in marine sediment pore waters  

Microsoft Academic Search

Fluorescent dissolved organic matter (FDOM) in sediment pore waters from contrasting sites in the Chesapeake Bay and along the mid-Atlantic shelf\\/slope break was studied using three-dimensional fluorescence spectroscopy. Benthic fluxes of FDOM were also examined at the Chesapeake Bay sites. The major fluorescence peaks observed in these pore waters corresponded to those observed in the water column. These included peaks

David J. Burdige; Scott W. Kline; Wenhao Chen

2004-01-01

114

DETERMINATION OF OCTANOL/WATER DISTRIBUTION COEFFICIENTS, WATER SOLUBILITIES, AND SEDIMENT/WATER PARTITION COEFFICIENTS FOR HYDROPHOBIC ORGANIC POLLUTANTS  

EPA Science Inventory

Octanol/water distribution coefficients, water solubilities, and sediment/water partition coefficients are basic to any assessment of transport or dispersion of organic pollutants. In addition, these determinations are prerequisites for many chemical or biological process studies...

115

Seasonal variations in pore water and sediment geochemistry of littoral lake sediments (Asylum Lake, MI, USA)  

PubMed Central

Background Seasonal changes in pore water and sediment redox geochemistry have been observed in many near-surface sediments. Such changes have the potential to strongly influence trace metal distribution and thus create seasonal fluctuations in metal mobility and bioavailability. Results Seasonal trends in pore water and sediment geochemistry are assessed in the upper 50 cm of littoral kettle lake sediments. Pore waters are always redox stratified, with the least compressed redox stratification observed during fall and the most compressed redox stratification observed during summer. A 2-step sequential sediment extraction yields much more Fe in the first step, targeted at amorphous Fe(III) (hydr)oxides (AEF), then in the second step, which targets Fe(II) monosulfides. Fe extracted in the second step is relatively invariant with depth or season. In contrast, AEF decreases with sediment depth, and is seasonally variable, in agreement with changes in redox stratification inferred from pore water profiles. A 5-step Tessier extraction scheme was used to assess metal association with operationally-defined exchangeable, carbonate, iron and manganese oxide (FMO), organic/sulfide and microwave-digestible residual fractions in cores collected during winter and spring. Distribution of metals in these two seasons is similar. Co, As, Cd, and U concentrations approach detection limits. Fe, Cu and Pb are mostly associated with the organics/sulfides fraction. Cr and Zn are mostly associated with FMO. Mn is primarily associated with carbonates, and Co is nearly equally distributed between the FMO and organics/sulfide fractions. Conclusion This study clearly demonstrates that near-surface lake sediment pore water redox stratification and associated solid phase geochemistry vary significantly with season. This has important ramifications for seasonal changes in the bioavailability and mobility of trace elements. Without rate measurements, it is not possible to quantify the contribution of various processes to natural organic matter degradation. However, the pore water and solid phase data suggest that iron reduction and sulfate reduction are the dominant pathways in the upper 50 cm of these sediments.

Koretsky, Carla M; Haas, Johnson R; Miller, Douglas; Ndenga, Noah T

2006-01-01

116

Suspended sediment dynamics in the Kromme Rijn river: indication for intense fine sediment exchange between water column and streambed  

NASA Astrophysics Data System (ADS)

The limited transparency of the river water of the Kromme Rijn, a dammed distributary of the Rhine River in the Netherlands, restricts the ecological function of the stream and the achievement of the EU-Water Framework Directive targets. To increase water transparency in this river, the 'Hoogheemraadschap De Stichtse Rijnlanden' (HDSR) water authority considers to design one or more large-scale sediment traps. For an optimal design of these possible sediment traps, further knowledge about the local sediment characteristics and sedimentation and resuspension rates is a prerequisite. At the request of the HDSR water authority, we studied the fine sediment characteristics and dynamics in the Kromme Rijn river and its tributaries. Between summer 2010 and summer 2011, eleven monthly water samples were collected from six monitoring locations in the 25 km long reach of the Kromme Rijn river between the inlet from the Nederrijn river and Utrecht. Additional samples were collected from seven monitoring locations in streams and canals discharging into the Kromme Rijn river. The water samples were analysed for suspended sediment concentration and the suspended sediment was analysed for loss on ignition and particle size distribution by laser diffraction. In addition, at these monitoring locations, small sediment traps with an 8 cm circular opening were installed at 0.7 m below the water surface to measure the gross long-term sedimentation rate. These sediment traps were emptied every two months. During the monitoring period, the average sediment load in the Kromme Rijn near the inlet was 112 g/s and decreased to about 90 g/s near Utrecht. The vast majority of the sediment load (91%) in the main branch of the Kromme Rijn originates from the inlet from the Nederrijn river. The 2-16 ?m and 16-63 ?m particle size classes comprise about 80% of the suspended sediment. The average organic fraction of the suspended sediment was 36%. The sediment collected from the sediment traps were slightly finer and contained less organic matter (20%). The long-term (>2 months) average gross sedimentation flux in the Kromme Rijn river was measured to be 330 g m-2 d-1. As the sediment load only decreases by 20% in the 25 km long studied reach of the Kromme Rijn river and the sediment supply from the tributary streams and canals is limited, this gross sedimentation flux should be compensated by an average gross resuspension flux of approximately 240 g m-2 d-1. This would imply that the river reach length over which the effect of a possible sediment trap is noticeable is limited to about 5-10 km.

Van den Boomen, R.; Zweers, A. J.; Van der Perk, M.

2012-04-01

117

Chemistry of Stream Sediments and Surface Waters in New England  

USGS Publications Warehouse

Summary -- This online publication portrays regional data for pH, alkalinity, and specific conductance for stream waters and a multi-element geochemical dataset for stream sediments collected in the New England states of Connecticut, Maine, Massachusetts, New Hampshire, Rhode Island, and Vermont. A series of interpolation grid maps portray the chemistry of the stream waters and sediments in relation to bedrock geology, lithology, drainage basins, and urban areas. A series of box plots portray the statistical variation of the chemical data grouped by lithology and other features.

Robinson, Gilpin R., Jr.; Kapo, Katherine E.; Grossman, Jeffrey N.

2004-01-01

118

[Mutagenic properties of inland waters and sediments in northern Poland].  

PubMed

Mutagenic properties of inland waters in northern Poland were evaluated using the Ames test. The tested surface waters were characterised by low mutagenic impact, while the majority of bottom sediment samples turned out to be highly mutagenic. The mutagenic rates (MR) of sediments ranged from 2 to 169 and depended on pollution of aquatic environment by organic substances and bacteria Escherichia coli. The most polluted sites of the studied rivers and lakes were indicated (MR=158, 169). This information should be useful for local governments as well as habitants. PMID:17044307

Niemirycz, Elzbieta; Kwieci?ska, Agnieszka

2006-01-01

119

Bacterial Mercury Methylation At The Sediment-Water Interface Of Mercury Contaminated Sediments  

EPA Science Inventory

Bench scale experiments were conducted to improve our understanding of bacterial mediation of mercury transformation (methylation), specifically those factors which govern the production of methyl mercury (MeHg) at the sediment-water interface. The greatest cause for concern re...

120

Development of Standardized Domestic Hot Water Event Schedules for Residential Buildings  

SciTech Connect

The Building America Research Benchmark is a standard house definition created as a point of reference for tracking progress toward multi-year energy savings targets. As part of its development, the National Renewable Energy Laboratory has established a set of domestic hot water events to be used in conjunction with sub-hourly analysis of advanced hot water systems.

Hendron, R.; Burch, J.

2008-08-01

121

Microbial quality of domestic and imported brands of bottled water in Trinidad  

Microsoft Academic Search

A cross-sectional study was conducted to determine the microbial quality of domestic and imported brands of bottled water available in Trinidad, purchased from six geographical regions in Trinidad, and representing the whole island. A sample size of 344 bottles of water was determined by using a precision rate of 2% and a Type 1 error of 5%. The membrane filter

J. Bharath; M. Mosodeen; S. Motilal; S. Sandy; S. Sharma; T. Tessaro; K. Thomas; M. Umamaheswaran; D. Simeon; A. A. Adesiyun

2003-01-01

122

Tapping the sun. An Arizona homeowner's guide to buying a solar domestic hot water system  

Microsoft Academic Search

After a brief review of the nation's energy problems, the nature of solar energy and its availability are briefly described. Some commonly asked technical, economic, and political questions concerning solar domestic hot water systems are addressed. Generic solar water heating systems are described, including diagrams of them and explanations of how they work. System sizing is discussed, and methods and

M. R. Anderson; J. A. Kimball

1981-01-01

123

Geographic constraints on passive solar domestic hot water systems due to pipe freezing  

Microsoft Academic Search

The supply and return piping of passive solar domestic hot water systems (SDHWS) is typically exposed to ambient weather conditions, and damaging pipe freeze is a major concern. This paper presents a pipe-freeze model that accounts for hot water draws and uses 30 years of actual weather data. The simulation results are cast in terms of pipe-freeze probabilities. Using contour

Jim Salasovich; Jay Burch; Greg Barker

2002-01-01

124

Thermal analysis of including phase change material in a domestic hot water cylinder  

Microsoft Academic Search

The domestic electrical hot water cylinder used in this paper incorporates encapsulated phase change material (PCM) placed in 57 vertical pipes. The use of PCM increases the thermal energy storage capacity of the cylinder and allows the use of low cost electricity during low peak periods. The operational mode of the system is based on heating the water and melting

A. de Gracia; E. Oró; M. M. Farid; L. F. Cabeza

2011-01-01

125

The Chemical Quality of Self-Supplied Domestic Well Water in the United States  

Microsoft Academic Search

Existing water quality data collected from domestic wells were summarized to develop the first national-scale retrospective of self-supplied drinking water sources. The contaminants evaluated represent a range of inorganic and organic compounds, and although the data set was not originally designed to be a statistical representation of national occurrence, it encompasses large parts of the United States including at least

Michael J. Focazio; Deborah Tipton; Stephanie Dunkle Shapiro; Linda H. Geiger

2006-01-01

126

Combination split system air conditioner and compression cycle domestic hot water heating apparatus  

Microsoft Academic Search

A conventional split system air conditioner is combined with a compression cycle or heat pump system for supplying heat to a domestic water heater. The units are combined in such a way that significant energy savings can be achieved by circulating air in series through the outdoor evaporator coil of the hot water heating system and then through the condensing

V. O. Bahel; R. R. Kuehner; R. H. Rosenberg

1980-01-01

127

Heat transport near sediment-water interfaces with bedforms  

NASA Astrophysics Data System (ADS)

The mechanical and thermal energy balance of streams, underlying sediments, and adjacent aquifers controls the distribution of lotic organisms. Thus, the energy transport within and between these systems is an issue of utmost importance in terms of understanding their ecology and biogeochemistry. In fast-flow systems, heat advection is equally important as, or more important than, heat conduction. In recent years, heat has been used as a tracer for fluid flow in deep aquifers as well as shallow unconsolidated fluvial deposits. However, recent studies have not addressed how fluid exchange across sediment-water interfaces (SWIs), driven by current-bedform interactions, affects thermal energy transport within the sediments. Moreover, even less is known regarding similar systems subjected to ambient groundwater discharge at a different temperature, e.g., gaining streams. We will present results of multiphysics numerical modeling along SWIs. Turbulent flow within the overlying water column (e.g., a river) is represented by the k-? closure scheme for the Reynolds-averaged Navier-Stokes equations. Porous media flow within the sediments is governed by the groundwater flow equation. The water column and sediment flow problems are sequentially coupled, with the turbulent water column flow determining the pressure boundary along the SWI. Heat transport within the sediments is governed by the advection-dispersion equation while the flow field is determined a priori by the porous flow problem. Temperature effects on fluid properties are ignored. We do not model heat transport within the water column and instead consider the SWI as a constant-temperature boundary (i.e., the river is well-mixed) for the porous media domain. The numerical modeling is implemented using FEMLAB and CFD-ACE+. Cases with and without ambient groundwater discharge will be presented. Our results have implications not only on lotic ecology but also on the interpretation of past heat tracing experiments and the design of future heat tracer studies.

Cardenas, M. B.; Wilson, J. L.

2005-12-01

128

Sediment-water fluxes of mercury in Lavaca Bay, Texas  

SciTech Connect

The aqueous flux of inorganic Hg and monomethyl Hg from sediments to the water column was determined at several sites in Lavaca Bay, an estuary along the Texas Coast, historically impacted by Hg discharges. Diffusive fluxes were calculated at 15 sites using interstitial pore water gradients and compared to direct flux measurements obtained at two sites using benthic flux chambers. The diffusive flux of monomethyl mercury (MMHg), when modeled as a chloride species, varied over 3 orders /of magnitude from 0.2 to 1500 ng m{sup {minus}2} day{sup {minus}1}. Diffusive fluxes determined at a single site revealed that MMHg fluxes varied seasonally; maximal fluxes occurred in late winter to early spring. Flux chamber deployments at an impacted site revealed t hat MMHg was the Hg species entering the water column from sediments and the flux was not in steady-state; there was a strong diurnal signal with most of the MMHg flux occurring during dark periods. The flux of inorganic Hg was smaller and not as easily discernible by this method. The MMHg flux during the dark period was about 6 times greater than the estimated diffusional flux for MMHgCl, suggesting that biological and/or chemical processes near the sediment-water interface were strongly mediating the sediment-water exchange of MMHg.

Gill, G.A. [Texas A and M Univ., Galveston, TX (United States); Bloom, N.S. [Frontier Geosciences Inc., Seattle, WA (United States); Cappellino, S. [Parametrix, Inc., Houston, TX (United States); Driscoll, C.T. [Syracuse Univ., NY (United States). Dept. of Civil and Environmental Engineering; Dobbs, C.; McShea, L. [Aluminum Co. of America, Point Comfort, TX (United States); Mason, R. [Univ. of Maryland, Solomons, MD (United States). Chesapeake Biological Lab.; Rudd, J.W.M. [Dept. of Fisheries and Oceans, Winnipeg, Manitoba (Canada). Freshwater Inst.

1999-03-01

129

Towards Sustainable Water Quality In Estuarine Impoundments: Sediment Processes.  

NASA Astrophysics Data System (ADS)

Several estuarine impoundment schemes have been built or are proposed in the UK and worldwide. The impounding of estuaries is currently a popular approach to urban regeneration in the UK. By creation of an aesthetically pleasing amenity impound- ment, including the drowning of "unsightly" tidal mud flats, it is hoped that prestige development will be encouraged in the estuarine area. Impounding fundamentally alters the dynamics of estuaries, with consequences in terms of sedimentation patterns and rates, and water quality. The SIMBA Project at- tempts to understand the controls on water quality in impoundments, with a view to- wards long term and sustainable high water quality through good barrage design and management practice. The results of process based studies, concentrating on interactions between sediment and water quality in the systems, are presented. A series of sequential extraction exper- iments have been carried out on cores of sediment to model the releases from sediment under different environmental conditions likely to be encountered in the impound- ments. Results are related to similar experiments carried out on suspended particulate material, and to pore-water experiments carried out using gel-probes.

Wright, J.; Worrall, F.

130

Sediment records of fallout radionuclides and their application to studies of sediment-water interactions  

Microsoft Academic Search

The fallout radionuclides210Pb and137Cs are widely used to date environmental records contained in lake sediments. Since the radionuclide records are themselves\\u000a the outcome of the transformation of atmospheric fallout by mediating transport processes from the catchment, through the\\u000a water column and post-depositional migration via pore waters, reliable models of these processes are crucial to accurate dating.\\u000a The large quantities of

P. G. Appleby

1997-01-01

131

Arsenic distribution in water/sediment system of Sevojno.  

PubMed

Arsenic is a toxic and carcinogenic element. Its toxicity depends on its oxidation state and its concentration. The aim of this paper is to determine, for the first time, the concentration levels of arsenic in water and sediment during the spring/summer period of 2009 in Sevojno, a region in West Serbia with a long industrial tradition, as well as to determine the model of arsenic distribution in water/sediment system and the level of its compatibility with the existing theoretical model. Adsorption is a continual process in the environment. It plays a very important role in the transport and fate of pollutants, especially in sediment. The adsorption of arsenic was examined using the Freundlich adsorption isotherm. PMID:21409362

Aksentijevi?, Snežana; Kiurski, Jelena; Vasi?, Milica Vu?ini?

2011-03-17

132

Development of the sediment and water quality management strategies for the Salt-water River, Taiwan.  

PubMed

The Salt-water River watershed is one of the major river watersheds in the Kaohsiung City, Taiwan. Water quality and sediment investigation results show that the river water contained high concentrations of organics and ammonia-nitrogen, and sediments contained high concentrations of heavy metals and organic contaminants. The main pollution sources were municipal and industrial wastewaters. Results from the enrichment factor (EF) and geo-accumulation index (Igeo) analyses imply that the sediments can be characterized as heavily polluted in regard to Cd, Cr, Pb, Zn, and Cu. The water quality analysis simulation program (WASP) model was applied for water quality evaluation and carrying capacity calculation. Modeling results show that the daily pollutant inputs were much higher than the calculated carrying capacity (1050 kg day(-1) for biochemical oxygen demand and 420 kg day(-1) for ammonia-nitrogen). The proposed watershed management strategies included river water dilution, intercepting sewer system construction and sediment dredging. PMID:21392809

Lin, C E; Chen, C T; Kao, C M; Hong, A; Wu, C Y

2011-03-09

133

Is all domestic water consumption sensitive to price control?  

Microsoft Academic Search

This paper presents a model of residential water demand based on the Stone–Geary utility function, which explicitly considers a threshold of water that is insensitive to price and a quantity that can adapt instantaneously to price changes. First, the threshold is assumed constant, being then allowed to vary according to past levels of consumption, a proxy for households' water-using equipment

Roberto Martínez-Espiñeira; Céline Nauges

2004-01-01

134

Hourly water consumption and egg formation in the domestic fowl  

Microsoft Academic Search

Observations on the water intake of four laying hens indicate that consumption is related to the egg formation. The maximum intakes occur just after the oviposition (50 ml\\/h) and during the albumen plumping (37 ml\\/h). Data obtained around the time of oviposition suggest that at this moment water intake is connected to oviposition rather than ovulation. A comparison between water

P. Mongin; B. Sauveur

1974-01-01

135

Influence of colloids on sediment-water partition coefficients of polychlorobiphenyl congeners in natural waters  

Microsoft Academic Search

Measurements of sediment-water partitioning of polychlorobiphenyl (PCB) congeners in Lake Superior provide some of the first field evidence demonstrating the importance of colloids to the fates of highly hydrophobic organic pollutants. Laboratory-derived correlations between sediment-water distribution coefficients and properties of both the contaminant (octanol-water partition coefficient) and the suspended solids (organic carbon content, concentration) do not accurately predict PCB speciation

Joel E. Baker; Paul D. Capel; Steven J. Eisenreich

1986-01-01

136

A memory model of sedimentation in water reservoirs  

NASA Astrophysics Data System (ADS)

? We present a model of water reservoir, where the sediments flux is governed by a fractional diffusion equation. ? The additional parameter is the fractional order of the time derivative and accounts for the whole history of the flux. ? We obtain the solution when the flux is constant at the source and is arbitrarily given at the output.

Caputo, Michele; Carcione, José M.

2013-01-01

137

Sediment testing intermittent renewal system for the automated renewal of overlying water in toxicity tests with contaminated sediments  

SciTech Connect

A sediment testing intermittent renewal (STIR) system (stationary or portable) for invertebrate toxicity testing with contaminated sediments has been successfully developed and thoroughly tested at ERL-Duluth. Both the stationary and portable systems enable the maintenance of acceptable water quality (e.g. DO) through the capability of automatically renewing overlying water in sediment tests at rates ranging from 1 to 21 volume renewals/day. The STIR system not only significantly reduces the labor associated with renewal of overlying water but also affords a gentle exchange of water that results in virtually no sediment resuspension. Both systems can also be installed in a compact vented enclosure to permit safe testing of hazardous contaminated sediments. To date the STIR system has been used extensively for conducting 10-day bulk sediment tests with Chironomus tentans, Hyalella azteca and Lumbriculus variegatus.

Benoit, D.A.; Phipps, G.L.; Ankley, G.T.

1993-01-01

138

Final reliability and materials design guidelines for solar domestic hot-water systems  

SciTech Connect

This document provides solar-energy-system engineers, designers, and manufacturers with a stand-alone publication containing the concepts and techniques for developing reliable solar domestic hot-water systems. The minimum instrumentation required to determine if a domestic hot-water system is operating properly is discussed, and system start-up and trouble-shooting information is supplied. Detailed sizing, design, or installation information is not provided. This document includes an evaluation of the reliability of six generic solar domestic hot-water systems - drain-down, drain-back, circulating-water, thermosiphon, antifreeze, and air systems. Failure-rate data for these evaluations were obtained from the open literature. Reliability block diagrams are used to analyze collector panels as well as the generic systems. System reliability results are shown as estimated mean time between failures, based on 6-hr/d operation. For other operating times, the duty-cycle concept may be applied similarly. Materials considerations are covered for common components in solar domestic hot-water systems. Information is also presented on glycol-testing and water-scaling predictions.

Not Available

1981-09-01

139

Methanobrevibacter ruminantium as an Indicator of Domesticated-Ruminant Fecal Pollution in Surface Waters?  

PubMed Central

A PCR-based assay (Mrnif) targeting the nifH gene of Methanobrevibacter ruminantium was developed to detect fecal pollution from domesticated ruminants in environmental water samples. The assay produced the expected amplification product only when the reaction mixture contained DNA extracted from M. ruminantium culture, bovine (80%), sheep (100%), and goat (75%) feces, and water samples from a bovine waste lagoon (100%) and a creek contaminated with bovine lagoon waste (100%). The assay appears to be specific and sensitive and can distinguish between domesticated- and nondomesticated-ruminant fecal pollution in environmental samples.

Ufnar, Jennifer A.; Wang, Shiao Y.; Ufnar, David F.; Ellender, R. D.

2007-01-01

140

A Recirculating Sea Water Benthic Chamber for the Study of the Biogeochemistry of Petroleum Components at the Sediment Water Interface.  

National Technical Information Service (NTIS)

The experimental benthic chamber was designed to conduct both laboratory and in situ investigations on the transport and degradation of petroleum type hydrocarbons at the sediment water interface, and to investigate the sediment/water/organism interaction...

C. L. Winget

1978-01-01

141

Extraction and concentration of phenolic compounds from water and sediment  

USGS Publications Warehouse

Continuous liquid-liquid extractors are used to concentrate phenols at the ??g l-1 level from water into dichloromethane; this is followed by Kuderna-Danish evaporative concentration and gas chromatography. The procedure requires 5 h for 18 l of sample water. Overall concentration factors around 1000 are obtained. Overall concentration efficiencies vary from 23.1 to 87.1%. Concentration efficiencies determined by a batch method suitable for sediments range from 18.9 to 73.8%. ?? 1980.

Goldberg, M. C.; Weiner, E. R.

1980-01-01

142

Shallow pore water sampling in reef sediments  

Microsoft Academic Search

Several new techniques have been developed to allow the geochemical characterization of shallow pore waters in reefs. First,\\u000a a new method was developed for using non-metallic well-points to sample pore waters from shallow depths (<1?m) in coral reefs\\u000a with unconsolidated substrates. These PVC well-points can be made faster and at less expense than well-points made of stainless\\u000a steel. They also

J. L. Falter; F. J. Sansone

2000-01-01

143

Domestic air-conditioner and integrated water heater for subtropical climate  

Microsoft Academic Search

The technology of using a heat pump for space conditioning and domestic hot water heating in residences has been developed for half a century. The earlier air-to-water heat pumps and water-heating heat pumps suffered from drawbacks like high costs, unreliable operation, and inflexible applications. They were not well positioned in the market to attract customers. This paper introduces a novel

Jie Ji; Tin-tai Chow; Gang Pei; Jun Dong; Wei He

2003-01-01

144

Technical evaluation of a small-scale reverse osmosis desalination unit for domestic water  

Microsoft Academic Search

Tunisian standards for drinking water tolerate a maximum Total Dissolved Salts (TDS) of 1.5 g\\/L. The domestic water presents usually a salinity greater than 0.5 g\\/L. In the last few years, several small capacity reverse osmosis desalination prototypes have been marketed. They are used to desalinate brackish water with TDS lower than 1.5 g\\/L. The performances of such type of

H. Elfil; A. Hamed; A. Hannachi

2007-01-01

145

Investigation of the spreading and dilution of domestic waste water inputs into a tidal bay using the finite-volume model FVCOM  

NASA Astrophysics Data System (ADS)

The 'Jade Bay' is a tidal bay located in the western part of the German Wadden Sea, southern North-Sea coast. During particularly heavy rain falls, rain water mixed with domestic waste water is discharged into the bay due to the limited capacities of the waste water treatment plant of the city of Wilhelmshaven. As the discharge point is located only a few hundred meters from a public bathing beach it is important to know spreading and dilution of the waste waters by tidal and wind-driven mixing. To model the behaviour of the waste water plumes, the unstructured mesh finite-volume model FVCOM (Chen and al., 2003) is used, which allows to cover the large area of the Jade and the nearby North Sea with a relatively high resolution near the point of discharge and a coarser resolution at the outer edges of the study side. We adapted the included sediment module of FVCOM to handle the sedimentation, decay and evolution in the bottom sediments of the discharged waste water particles, especially with respect to bacteria. Furthermore, alternative discharge points located in the interior of the Jade bay were tested, which might be more suited for a faster dilution and a smaller residence time of the waste water particles in the tidal bay.

Lettmann, Karsten; Wolff, Jörg-Olaf; Liebezeit, Gerd; Meier, Georg

2010-05-01

146

Nutritional composition of water hyacinths grown on domestic sewage  

Microsoft Academic Search

A nutrient analysis of water hyacinths grown in sewage wastewaters was conducted. Crude protein averaged 32.9% dry weight\\u000a in the leaves, where it was most concentrated. The amino acid content of water hyacinth leaves was found to compare favorably\\u000a with that of soybean and cottonseed meal. The vitamin and mineral content of dried water hyacinths met or exceeded the FAO

B. C. Wolverton; Rebecca C. Mcdonald

1978-01-01

147

30 CFR 77.216-2 - Water, sediment, or slurry impoundments and impounding structures; minimum plan requirements...  

Code of Federal Regulations, 2010 CFR

...2010-07-01 false Water, sediment, or slurry impoundments and impounding structures...77.216-2 Water, sediment, or slurry impoundments and impounding structures...design storm conditions, sediment or slurry level, water level and other...

2010-07-01

148

30 CFR 77.216-2 - Water, sediment, or slurry impoundments and impounding structures; minimum plan requirements...  

Code of Federal Regulations, 2010 CFR

...2009-07-01 false Water, sediment, or slurry impoundments and impounding structures...77.216-2 Water, sediment, or slurry impoundments and impounding structures...design storm conditions, sediment or slurry level, water level and other...

2009-07-01

149

Relative role of pore water versus ingested sediment in bioavailability of organic contaminants in marine sediments  

SciTech Connect

Experimental data for fluoranthene and feeding selectivity in combination with reaction-diffusion modeling suggest that ingestion of contaminated sediment may often be the dominant uptake pathway for deposit-feeding invertebrates in sediments. A dietary absorption efficiency of 56% and accompanying forage ratio of 2.4 were measured using natural sediment that had been dual-labeled ({sup 14}C:{sup 51}Cr) with fluoranthene and fed to the marine deposit-feeding polychaete Capitella species I. Only 3 to 4% of the total absorption could be accounted for by desorption during gut passage. These data were then used as input into a reaction-diffusion model to calculate the importance of uptake from ingested sediment relative to pore-water exposure. The calculations predict a fluoranthene dietary uptake flux that is 20 to 30 times greater than that due to pore water. Factors that act to modify or control the formation of local chemical gradients, boundary layers, or dietary absorption rates including particle selection or burrow construction will be important in determining the relative importance of potential exposure pathways. From a chemical perspective, the kinetics of the adsorption and desorption process are especially important as they will strongly influence the boundary layer immediately surrounding burrowing animals or irrigated tubes. The most important biological factors likely include irrigation behavior and burrow density and size.

Forbes, T.L.; Hansen, R.; Kure, L.K. [National Environmental Research Inst., Roskilde (Denmark). Dept. of Marine Ecology and Microbiology; Forbes, V.E. [Univ. of Maine, Walpole, ME (United States). Dept. of Oceanography; Giessing, A. [National Environmental Research Inst., Roskilde (Denmark). Dept. of Marine Ecology and Microbiology]|[Roskilde Univ. Center (Denmark). Dept. of Life Sciences and Chemistry

1998-12-01

150

Rainwater Harvesting Potential for Domestic Water Supply in Edo State  

Microsoft Academic Search

In the face of increasing scarcity of water resources, there is a need for communities to undertake audits of their current rainwater harvesting potential as a practical and promising alternative solution for water shortage. Despite the importance of rainwater harvest in socio-economic development of communities, very little information exists in the literature concerning it. This paper is an attempt to

S. I. Oni; Emmanuel Ege

2008-01-01

151

Evaluation of petroleum-degrading potential of bacteria from water and sediment.  

PubMed Central

Bacteria from water and sediment of an oil-polluted harbor were examined for ability to degrade petroleum. Water samples contained a greater variety of bacterial species capable of degrading petroleum than sediment. Cultures from both water and sediment contained Pseudomonas and Acinetobacter spp. Bacteria present in the water samples produced significantly greater degradation of 2-,3-,4-, and 5-ring cycloalkanes and mono-, di-, tri-, tetra-, and pentaaromatics compared with bacteria in sediment samples.

Walker, J D; Colwell, R R; Petrakis, L

1975-01-01

152

Interaction between water, sediments and radionuclides.  

National Technical Information Service (NTIS)

A model-based measurements program was carried out to evaluate the primary mechanisms controlling transport of uranium 238 and thorium 232 decay chain radionuclides in Quirke Lake, a water body draining much of the uranium mining and milling district near...

W. J. Snodgrass P. McKee J. Garnett L. Stieff

1988-01-01

153

Solar heating, cooling and domestic hot water system installed at Columbia Gas System Service Corporation, Columbus, Ohio  

NASA Astrophysics Data System (ADS)

The solar energy system installed in the building has 2,978 sq ft of single axis tracking, concentrating collectors and provides solar energy for space heating, space cooling and domestic hot water. A 1,200,000 Btu/hour water tube gas boiler provides hot water for space heating. Space cooling is provided by a 100 ton hot water fired absorption chiller. Domestic hot water heating is provided by a 50 gallon natural gas domestic storage water heater. Extracts from the site files, specification references, drawings, installation, operation and maintenance instructions are included.

1980-11-01

154

Laminar flow of fine sediment-water mixtures  

NASA Astrophysics Data System (ADS)

Flows of sediment-water mixture (suspensions) are common superficial processes in nature. To investigate the possibility of predicting the behaviour of such flows, we study the free surface flow of a clay-water suspension down a slope, which may represent a simple realistic model for the flow of some concentrated sediment-water mixture in a natural environment. The hydrodynamic lubrication equations governing the flow are derived from the full Navier-Stokes equations, including an appropriate tensorial expression for the constitutive equation of the suspension (a Herschel-Bulkley fluid with a hysteresis in the yield strength). Results have been obtained for the free surface and length of an unsteady, laminar, isothermal flow of the suspension. The theory is in good agreement with laboratory experiments with fine clay suspensions.

Battaglia, M.; Borgia, A.

2000-03-01

155

Dissolved iodine flux from estuarine sediments and implications for the enrichment of iodine at the sediment water interface  

NASA Astrophysics Data System (ADS)

During the anaerobic decomposition of organic matter in sediments iodine is released into solution. Three techniques have been applied to independently estimate the resulting flux of soluble I from the sediments to the overlying water of Mud Bay, Georgetown, South Carolina. Flux estimates (summer) range between ~ 5 and 41 ?mol/m 2/day. The estimates predicted from either the pore water I concentration gradient across the sediment-water interface or the dissolved I production rate are higher than the apparent flux measured directly at the same site. This suggests that I which is released to the pore water under the anoxic conditions below the sediment surface reacts with a sedimentary component at or near the sediment water interface and is lost from solution.

Ullman, William J.; Aller, Robert C.

1980-08-01

156

Tomographic imaging of residual hydrocarbon in water saturated unconsolidated sediments  

NASA Astrophysics Data System (ADS)

Determining the amount and distribution of residual hydrocarbon in granular media is important for monitoring secondary and tertiary recovery processes during hydrocarbon production. The distribution of residual hydrocarbon is affected by the structure of the granular media (layering, grain, pore size, etc.), and the method used to produce oil (single well, multi-well, etc.). Seismic technique are often used to monitor the recovery process, thus, it is required that the effect of structure and hydrocarbon distribution be understood. The objectives of this thesis work is to determine if acoustic methods can (1) delineate sediment structure caused by variation in grain size and (2) delineate the amount and spatial distribution of residual hydrocarbon. Naturally occurring sediments are often complicated in composition and structure that results in a range of seismic attenuation mechanisms. For this study, synthetic sediments with idealized 3-D sediment structures were created from glass beads (with known composition and geometry) saturated with two fluid phase: water and paraffin wax. A series of control experiments were performed using different saturation techniques to (1) explore the immiscible fluid displacement processes and (2) to study the effect of amount and the spatial distribution of the immiscible fluid residue on the acoustic response. An acoustic tomographic approach was used to delineate the 3-D sediment structure and to study the effect of sediment structure on the amount and the spatial distribution of the immiscible fluid. From the control experiments, it was determined that the saturation method affected the residual wax distribution in the pores. The residual wax distribution can be categorized into four types, i.e. bridging, thin fingering, cements at grain contacts, and patchy saturation. The tomographic experiments determined that sediment structure caused by a variation in grain size could barely be determined seismically. However, the 3-D sediment structure was clearly determined when residual paraffin resided in the sediment. Even residual saturation of less than 1% altered the seismic signal of the sediments. Seismic-wave attenuation and velocity is sensitive to alteration of the grain contact stiffness even for only a few percent residual hydrocarbon saturation and to spatial features that are ˜1/100 of a wavelength. Thus the affect of micro-scale phenomena on macro-scale measurements of seismic wave attenuation and velocity cannot be ignored.

Li, Xun

2002-08-01

157

Persistent organic pollutants in water and surface sediments of Taihu Lake, China and risk assessment  

Microsoft Academic Search

Organic pollutants, especially persistent organic pollutants were examined in the water and surface sediments of Taihu Lake, China. Both 12 water and 12 sediment samples were collected over the lake. C-18 solid-phase extraction technique was applied to extract organic pollutants in collected water samples. Soxhlet extraction procedure was used to extract organic pollutants in sediment samples. The analysis was performed

Hai Wang; Chunxia Wang; Wenzhong Wu; Zheng Mo; Zijian Wang

2003-01-01

158

30 CFR 77.216 - Water, sediment, or slurry impoundments and impounding structures; general.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Water, sediment, or slurry impoundments and impounding structures...Installations § 77.216 Water, sediment, or slurry impoundments and impounding structures...structures which impound water, sediment, or slurry shall be required if such an...

2013-07-01

159

30 CFR 77.216 - Water, sediment, or slurry impoundments and impounding structures; general.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 false Water, sediment, or slurry impoundments and impounding structures...Installations § 77.216 Water, sediment, or slurry impoundments and impounding structures...structures which impound water, sediment, or slurry shall be required if such an...

2010-07-01

160

30 CFR 77.216 - Water, sediment, or slurry impoundments and impounding structures; general.  

Code of Federal Regulations, 2010 CFR

...2009-07-01 false Water, sediment, or slurry impoundments and impounding structures...Installations § 77.216 Water, sediment, or slurry impoundments and impounding structures...structures which impound water, sediment, or slurry shall be required if such an...

2009-07-01

161

Advanced biological unit processes for domestic water recycling  

Microsoft Academic Search

Abstract The potential of advanced,biological unit operations for the recycling of grey and black waters has been evaluated. The membrane,bioreactor (MBR) demonstrated,the greatest efficacy towards water recycling in terms of all the quality determinants. Both the biologically aerated filter (BAF) and the MBR were able to effectively treat the organic and physical pollutants in all the types of wastewater,tested. The

B. jefferson; A. l. Laine; T. Stephenson; S. j. Judd

162

European Modelling Group Solar Space Heating and Domestic Hot Water Systems.  

National Technical Information Service (NTIS)

The co-operative work within the European Modelling Group for Solar Heating Systems and Domestic Hot Water is undertaken as part of the CEC's research and development program on Solar Applications for Dwellings. During the last two years of operation of t...

O. Balslev-Olesen

1985-01-01

163

Low-Cost Solar Domestic Hot Water Systems for Mild Climates.  

National Technical Information Service (NTIS)

In FY99, Solar Heating and Lighting set the goal to reduce the life-cycle cost of saved-energy for solar domestic hot water (SDHW) systems in mild climates by 50%, primarily through use of polymer technology. Two industry teams (Davis Energy Group/SunEart...

J. Burch C. Christensen T. Merrigan R. Hewett G. Jorgensen

2005-01-01

164

Investigation of photovoltaic powered pumps in direct solar domestic hot water systems.  

National Technical Information Service (NTIS)

The performance of photovoltaic powered pumps in direct solar domestic hot water (PV-SDHW) systems has been studied. The direct PV- SDHW system employs a photovoltaic array, a separately excited DC- motor, a centrifugal pump, a thermal collector, and a st...

A. M. Al-Ibrahim S. A. Klein J. W. Mitchell W. A. Beckman

1996-01-01

165

Thermosiphon solar domestic water heating systems: long-term performance prediction using artificial neural networks  

Microsoft Academic Search

The objective of this work is to use artificial neural networks (ANN) for the long-term performance prediction of thermosiphonic type solar domestic water heating (SDWH) systems. Thirty SDWH systems have been tested and modelled according to the procedures outlined in the standard ISO 9459-2 at three locations in Greece. From these, data from 27 of the systems were used for

Soteris A Kalogirou; Sofia Panteliou

2000-01-01

166

Operation and Performance of Four Solar Domestic Hot-Water Systems.  

National Technical Information Service (NTIS)

In 1978 the Ontario Ministry of Municipal Affairs and Housing, with funds provided by the Ministry of Energy installed four package solar domestic hot water preheat systems in four Ontario Housing Corporation houses as part of the Housing and Energy Manag...

1982-01-01

167

Economic viability of heat pump desuperheaters for supplying domestic hot water  

Microsoft Academic Search

The heat reclaimer is a heat exchange device that removes superheat from the refrigerant gas in a heat pump or central air conditioning unit and uses that extracted energy to heat water for domestic uses. This analysis examines the energy-saving potential and economic benefit of the heat reclaimer. Energy savings were calculated using a modified bin analytical technique. Economic viability

Olszewski

1984-01-01

168

Measurements of heat losses from an insulated domestic hot water cylinder  

Microsoft Academic Search

The paper provides data for heat losses from exposed pipes, plugs, thermostat cap and base of an insulated domestic hot water cylinder (capacity 120 litres), and examines their influence, and the effect of air movement, on standing heat loss performance as prescribed by standard methods such as BS699. Results show that under 'still air' conditions heat losses from exposed areas

A. Simpson; G. Castles

1992-01-01

169

COST OPTIMIZATION OF LOW-COST SOLAR DOMESTIC HOT WATER SYSTEMS ASSISTED BY ELECTRIC ENERGY  

Microsoft Academic Search

In the present paper the optimization of the insulation thickness of the storage tank of a low cost solar domestic water heating system (SDWHS) is carried out. The system is equipped with an auxiliary heater in the tank. The model assumes that the auxiliary energy needed to face the energy requirement for a shower in the evening, is supplied to

Sergio Colle; Juan Pablo; L. C. Salazar; Samuel L. Abreu; Karime Glitz; Wilson Reguse

170

Factors Affecting Domestic Water Consumption in Rural Households upon Access to Improved Water Supply: Insights from the Wei River Basin, China  

PubMed Central

Comprehensively understanding water consumption behavior is necessary to design efficient and effective water use strategies. Despite global efforts to identify the factors that affect domestic water consumption, those related to domestic water use in rural regions have not been sufficiently studied, particularly in villages that have gained access to improved water supply. To address this gap, we investigated 247 households in eight villages in the Wei River Basin where three types of improved water supply systems are implemented. Results show that domestic water consumption in liters per capita per day was significantly correlated with water supply pattern and vegetable garden area, and significantly negatively correlated with family size and age of household head. Traditional hygiene habits, use of water appliances, and preference for vegetable gardening remain dominant behaviors in the villages with access to improved water supply. Future studies on rural domestic water consumption should pay more attention to user lifestyles (water appliance usage habits, outdoor water use) and cultural backgrounds (age, education).

Fan, Liangxin; Liu, Guobin; Wang, Fei; Geissen, Violette; Ritsema, Coen J.

2013-01-01

171

Maximum use of resources present in domestic "used water".  

PubMed

Environmental protection and the sustainable management of natural resources stand at the foreground of economic and technological activities worldwide. Current sewage technologies, however, deal with diluted wastes and do not focus on recovery and are therefore not sustainable. Here, the most promising methods available for the recovery of nutrients (nitrogen, phosphorus), organic material and energy from "used waters" are examined both at the decentralised and centralised level. Novel approaches for water processing, not implementing aerobic biological treatment as a core technology, are conceived and critically evaluated regarding efficiency, diffuse emissions and requisite costs. By implementing up-concentration of dilute wastewaters, the concentrated stream becomes suitable for the waste-to-energy strategy. The approach of up-concentration of municipal effluent at arrival at the water treatment plant followed by anaerobic digestion of organics and maximal reuse of the mineral nutrients and water is estimated to have a total cost of the order 0.9 euros/m(3); the latter is comparable to that of conventional aerobic treatment technologies which has little or no reuse. It is argued that in view of the fact that recovered nutrients will become of increasing economic and ecological value, this new conceptual design for the treatment of "used water" will become feasible in the next decade. PMID:19577923

Verstraete, Willy; Van de Caveye, Pieter; Diamantis, Vasileios

2009-07-04

172

Preliminary assessment of heavy metal contamination in surface water and sediments from Honghu Lake, East Central China  

NASA Astrophysics Data System (ADS)

Heavy metal concentrations in surface water and sediments collected from Honghu Lake in Hubei Province, China were analyzed, and ecological risks were evaluated according to the sediment quality guidelines. The results showed that the average concentrations of heavy metals in surface water were ranked as: As>Zn> Cu>Cr>Pb>Ni>Cd>Hg. In comparison with results reported in other rivers and the background values, The Honghu Lake was polluted by As, Cr, Pb, Cu and Ni. Most of metals might be mainly from fertilizers, industrial effluent and domestic wastewater around the lake. Heavy metals concentrations were relatively higher in the inlet area than in other areas. Negative correlations were observed between most heavy metals and pH, while a significant positive correlation was present between Zn, Cd and Pb. In the sediment core, Cu, Zn, Cr and Ni showed a decreasing trend while Cd present an increasing trend. The decrease of As, Cu, Zn, Cr and Ni in the 1990s might due to the flood event in 1998. The analysis of ecological risk assessment based on sediment quality guidelines suggested that heavy metals in most sediments from the Honghu Lake had moderate toxicity, with Cr being the highest priority pollutant.

Hu, Ying; Qi, Shihua; Wu, Chenxi; Ke, Yanping; Chen, Jing; Chen, Wei; Gong, Xiangyi

2012-03-01

173

Solar domestic hot water system installed at Texas City, Texas  

NASA Astrophysics Data System (ADS)

This is the final technical report of the solar energy system located at LaQuinta Motor Inn, Texas City, Texas. The system was designed to supply 63 percent of the total hot water load for a new 98 unit motor inn. The solar energy system consists of a 2100 square feet Raypack liquid flat plate collector subsystem and a 2500 gallon storage subsystem circulating hot water producing 3.67 x 10 to the 8th power Btu/year. Abstracts from the site files, specification references, drawings, installation, operation, and maintenance instructions are included.

1980-12-01

174

Dissolved sulfide distributions in the water column and sediment pore waters of the Santa Barbara Basin  

Microsoft Academic Search

Dissolved sulfide concentrations in the water column and in sediment pore waters were measured by square-wave voltammetry (nanomolar detection limit) during three cruises to the Santa Barbara Basin in February 1995, November–December 1995, and April 1997. In the water column, sulfide concentrations measured outside the basin averaged 3 ± 1 nM (n = 28) in the 0 to 600 m

JAMES S. KUWABARA; Alexander van Geen; DANIEL C. MCCORKLE; JOAN M. BERNHARD

1999-01-01

175

Numerical Simulation of Sediment-Associated Water Quality Processes for a Mississippi Delta Lake  

Technology Transfer Automated Retrieval System (TEKTRAN)

Three major sediment-associated processes were presented to describe the effects of sediment on lake water quality processes: the effect of suspended sediment on the light intensity for the growth of phytoplankton (PHYTO), the adsorption–desorption of nutrients by sediment, and the release of nutrie...

176

Mineralogical Evidence of Galvanic Corrosion in Domestic, Drinking Water Pipes  

EPA Science Inventory

Drinking water distribution system (DWDS) piping contains numerous examples of galvanically-coupled metals (e.g., soldered copper pipe joints, copper-lead pipes joined during partial replacements of lead service lines). The possible role of galvanic corrosion in the release of l...

177

Report on water quality, sediment and water chemistry data for water and sediment samples collected from source areas to Melton Hill and Watts Bar reservoirs  

SciTech Connect

Contamination of surface water and sediments in the Clinch River and Watts Bar Reservoir (CR/WBR) system as a result of past and present activities by the US Department of Energy (DOE) on the Oak Ridge Reservation (ORR) and also activities by non-ORR facilities are being studied by the Clinch River Environmental Restoration Program (CR-ERP). Previous studies have documented the presence of heavy metals, organics, and radionuclides in the sediments of reservoirs in the vicinity. In support of the CR-ERP, during the summer of 1991, TVA collected and evaluated water and sediment samples from swimming areas and municipal water intakes on Watts Bar Reservoir, Melton Hill Reservoir and Norris Reservoir, which was considered a source of less-contaminated reference or background data. Despite the numerous studies, until the current work documented by this report, relatively few sediment or water samples had been collected by the CR-ERP in the immediate vicinity of contaminant point sources. This work focused on water and sediment samples taken from points immediately downstream from suspected effluent point sources both on and off the ORR. In August and September, 1994, TVA sampled surface water and sediment at twelve locations in melton Hill and Watts Bar Reservoirs.

Tomaszewski, T.M.; Bruggink, D.J.; Nunn, D.L.

1995-08-18

178

Enhancement of natural circulation type domestic solar hot water system performance by using a wind turbine  

Microsoft Academic Search

Performance improvement of existing 200 litres capacity natural convection type domestic solar hot water system is attempted.\\u000a A two-stage centrifugal pump driven by a vertical axis windmill having Savonius type rotor is added to the fluid loop. The\\u000a windmill driven pump circulates the water through the collector. The system with necessary instrumentation is tested over\\u000a a day. Tests on Natural

K. K. Ramasamy; P. S. S. Srinivasan

2011-01-01

179

A longitudinal study of domestic water conservation behavior  

Microsoft Academic Search

A 1988 study of a school-linked sample in a metropolitan and a regional urban area established baseline data for knowledge, attitudes, intentions, and behavior with regard to water management and conservation (Murphy, Watson, & Moore, 1991). This paper reports on a 1991 follow-up, utilising both longitudinal and cross-sectional samples of students, teachers and parents, which aimed at identifying changes within

Susan Moore; Margot Murphy; Ray Watson

1994-01-01

180

Impact of domestic sewage on fresh water body.  

PubMed

In the present study various (physico-chemical) factors were assessed over a period of two years (from February 2002 to January 2004) to note the chemistry and quality of tank water in Bhalki town of Bidar. Physico-chemical factors like pH, dissolved oxygen, magnesium, chlorine, nitrite, sulphates and chemical oxygen demand were found with maximum concentration during summer season. Similarly, during monsoon season free carbon dioxide, alkalinity hardness, calcium, phosphate, silicon, total solids and biological oxygen demand; and in winter season organic matter were recorded. The concentrations viz., pH, hardness and nitrite were more compared to the potable water standard of WHO. The correlation matrix and dendrogram of physico-chemical factors have been computed and analysed. The positive co-relation coefficient observed between pH and magnesium, dissolved oxygen and hardness, free carbondioxide and calcium, alkalinity and nitrite, alkalinityand phosphate, alkalinity and biological oxygen demand, hardness and calcium, hardness and magnesium, magnesium and chlorine, nitrate and phosphate, nitrite and biological oxygen demand, phosphate and organic matter; and silicon and chemical oxygen demand. The dendrogram confirms chlorine, pH, hardness, silicon, total solids and sulphates are the key factors of the change in the chemistry of water body PMID:18972682

Shiddamallayya, N; Pratima, M

2008-05-01

181

Water-sediment exchange of nutrients during early diagenesis and resuspension of anoxic sediments from the Northern Adriatic Sea shelf  

Microsoft Academic Search

This paper presents the results of a study on nutrient exchange at the sediment-water interface which is caused by early diagenesis\\u000a and resuspension of bottom sediments. The research was carried out on anoxic silty-clay sediment cores collected south of\\u000a the Po river delta (Northern Adriatic Sea, Italy) in late summer.\\u000a \\u000a The early diagenetic processes were investigated by means of the

Federico Spagnoli; Maria Cristina Bergamini

1997-01-01

182

Life cycle environmental impact of a thermosyphonic domestic solar hot water system in comparison with electrical and gas water heating  

Microsoft Academic Search

A methodology for the environmental impact evaluation over the life span of a Domestic Solar Hot Water System (DSHWS) is presented. The results are compared to the environmental consequences of the conventional energy form substituted and the total environmental gain is calculated. For the purposes of this analysis, the “Eco-indicator ’99” Life Cycle Impact Assessment methodology was adopted and the

G. Tsilingiridis; G. Martinopoulos; N. Kyriakis

2004-01-01

183

The genotoxic hazards of domestic wastes in surface waters.  

PubMed

Despite the noteworthy genotoxic potency of many industrial wastewaters, the genotoxic hazard posed to the downstream ecosystem and its associated biota will be determined by genotoxic loading. Municipal wastewaters, although ranking low in potency, can achieve loading values that are several orders of magnitude greater than those of most industries. Although these wastewaters are generally mixtures of wastes from several different sources, the volumetric proportion of the daily discharge that is of industrial origin rarely exceeds 30%. Genotoxicity calculations for the Montreal Urban Community (MUC) municipal wastewater treatment facility indicate that over 90% of the genotoxic loading (31.1 kg benzo(a)pyrene equivalents per day) is nonindustrial in origin. Moreover, a mass balance of surface water genotoxicity for St. Lawrence river at Montreal indicates that over 85% of the total contributions from the Montreal region are nonindustrial in origin. Additional calculations for the Great Lakes, and other rivers throughout the world, provide further support of a strong relationship between surface water genotoxicity and population. Despite some information about physical/chemical properties, the identity of the putative genotoxins in municipal wastewaters and surface waters remains a mystery. Likely candidates include potent genotoxins, such as N-nitroso compounds and aromatic amines, known to be present in human sanitary wastes, as well as genotoxic PAHs known to be present in many municipal wastewaters. Calculations based on literature data indicate that human sanitary wastes may be able to account for a substantial fraction (4-70%) of the nonindustrial loading from municipal wastewaters. Similar calculations suggest that pyrogenic PAHs that enter municipal wastewaters via surface runoff can only account for a small fraction (<5%) of the genotoxic loading values discussed. PMID:9630643

White, P A; Rasmussen, J B

1998-06-01

184

Application of ecological modelling to investigate the impact of domestic waste water to one natural river system in tropical area (the nhue river, outskirts of hanoi, vietnam)  

NASA Astrophysics Data System (ADS)

Water quality modelling has been employed as an effective tool to investigate the ecological situation of surface water sources. Within a researching collaboration of Vietnamese and French scientists, one portion, 40 km, of the Nhue river, outskirts of Hanoi city, northern Vietnam, has been investigated since the river has been highly impacted from anthropogenic activities and one 1-D ecological river model was formed based on the investigation. In this paper, biochemical process equations integrated with hydraulic conditions and human alterations are presented as the basis for ecological variation of this river system. Investigation showed that at the origin the river water remains untouched (nutrients are low in natural tropical water) while downstream the river is full of domestic pollutants (organic materials and nutrients). From the hydraulic, biological, chemical data and fieldwork experiments, the sensitivity analysis and parameter estimation have been carried out to verify the biochemical processes and optimise this model. Most calculations (simulation, sensitivity functions and parameter estimation) were performed with AQUASIM, a computer program designed for simulation and data analysis of 1-D river and other aquatic systems. The other supporting calculations for system analysis were implemented with IDENT based on output of a sensitivity analysis carried out with AQUASIM. The simulation results accomplished with available data indicate that the sediment exchanges and biodegradation processes emerge as the most important features that influence the water quality of the river where water is usually overloaded by domestic wastewater and where hydraulic characters are less pronounced. The model construction and simulation results have also pointed out that the river water quality has been spoiled dramatically after the main open-air sewer of the Hanoi city, the To Lich river, excesses to the Nhue. Beside, a metal speciation module was proposed to integrate with existing biochemical model in order to simulate the metal fractions in water column and metal exchange between river water and sediment.

Trinh Anh, D.; Bonnet, M. P.; Prieur, N.

2003-04-01

185

Water and Sediment Yield from a Deciduous Forest Ecosystem in Istanbul-Turkey  

Microsoft Academic Search

The objectives of this paper are to present annual water yield and sediment loss from a forest ecosystem consisting of completely natural broadleaved old growth oak-beech stands and to show precipitation, streamflow, and sediment discharge trends over time. An experimental watershed has been monitored since 1979 for streamflow and water quality parameters including suspended sediment discharge. Data presented in this

Süleyman ÖZHAN; Ferhat GÖKBULAK; Yusuf SERENGIL

186

Sediment and Water Quality Response to Climate Change in Bai River Basin  

Microsoft Academic Search

Geographic informational system (GIS) and the Soil and Water Assessment Tool (SWAT) was used to simulate the transport of runoff, sediment, total nitrogen and total phosphorus into the Zhangjiafen stations. The main objective was to discuss climate change affecting on sediment and water quality. The results showed: The SWAT generally performs well and could accurately simulate monthly runoff, sediment, total

Qi Ji; Zheng Jiangkun; Yu Xinxiao

2011-01-01

187

Variations in Stream Water and Sediment Phosphorus among Select Ozark Catchments  

Microsoft Academic Search

Stream sediments play a large role in the transport and fate of soluble reactive phosphorus (SRP) in stream ecosystems, and equilibrium P concentrations (EPC 0) of benthic sediments at which P is neither adsorbed nor desorbed are often related to stream water SRP concentrations. Th is study evaluated (i) the variation among water chemistry and sediment-P interactions among streams draining

Brian E. Haggard; Douglas R. Smith; Kristofor R. Brye

2007-01-01

188

Fiber filter as an alternative to the process of flocculation–sedimentation for water treatment  

Microsoft Academic Search

The conventional treatment for production of drinking water from surface water generally consists of coagulation, flocculation, sedimentation and sand filtration. One of the main disadvantages of the conventional process combining sedimentation and filtration is the rather long residence time. This is mostly due to the flocculation and sedimentation phases (typically 2 h). The fiber filter recently developed has been very

J. J. Lee; J. H. Cha; R. Ben Aim; K. B. Han; C. W. Kim

2008-01-01

189

Sedimentation on the cold-water coral Lophelia pertusa: Cleaning efficiency from natural sediments and drill cuttings  

Microsoft Academic Search

Anthropogenic threats to cold-water coral reefs are trawling and hydrocarbon drilling, with both activities causing increased levels of suspended particles. The efficiency of Lophelia pertusa in rejecting local sediments and drill cuttings from the coral surface was evaluated and found not to differ between sediment types. Further results showed that the coral efficiently removed deposited material even after repeated exposures,

Ann I. Larsson; Autun Purser

2011-01-01

190

THE RELATIONSHIP OF BIOACCUMULATIVE CHEMICALS IN WATER AND SEDIMENT TO RESIDUES IN FISH: A VISUALIZATION APPROACH  

EPA Science Inventory

A visualization approach is developed and presented for depicting and interpreting bioaccumulation relationships and data, i.e., bioaccumulation factors (BAFs), biota-sediment accumulation factors (BSAFs) and chemical residues in fish, using water-sediment chemical concentration ...

191

INTERACTION OF METALS AND ORGAINIC CARBON COLLOIDS IN ANOXIC INTERSTITIAL WATERS OF MARINE SEDIMENTS  

EPA Science Inventory

Marine colloids are an important component of natural water geochemistry critical to the cycling, speciation and bioavailability of metals in marine sediments. In sediment, metals exist in three phases: particulate, colloidal and dissolved. Dissolved metal concentrations have bee...

192

Chemical composition of sediments, suspended matter, river water and ground water of the Nile (Aswan-Sohag traverse)  

Microsoft Academic Search

Sediment, suspended matter, river water and ground water samples were collected at twelve sites in the drainage valley of the Nile River, around Sohag (Central Egypt) and close to the Aswan High Dam. Elemental composition of the river water (27 elements), ground water (eight elements), suspended matter (12 elements) and sediments (12 elements) was studied. Aswan High Dam construction, agricultural

V. M. Dekov; Z. Komy; F. Araújo; A. Van Put; R. Van Grieken

1997-01-01

193

Environmental assessment for the domestic water supply upgrades and consolidation on the Savannah River Site  

SciTech Connect

The domestic water systems on the Savannah River Site (SRS) are currently in need of upgrading to ensure compliance with the Safe Drinking Water Act and South Carolina Department of Health and Environmental Control (SCDHEC) Drinking Water Regulations. The SRS has 28 separate goundwater-based drinking water systems in use across the site. These aging systems were designed and constructed in the 1950s and are now facing increasing difficulties in meeting cur-rent regulations. Audits of the systems conducted by SCDHEC in 1986, 1988, 1991, and 1993 identified shortfalls in meeting the requirements for secondary maximum containment levels (MCLS) and SCDHEC design standards. Secondary MCLs are those items, such as odor or appearance, that do not pose a direct health impact. SRS has committed to SCDHEC to correct the drinking water discrepancies and construct two new consolidated inter-area drinking water systems. Upgrading the SRS drinking water systems would be necessary to support site activities regardless of the makeup or the mission at SRS. As such, the proposed upgrade and consolidation of SRS domestic water systems is treated as part of the ``No Action`` alternative for the Programmatic Environmental Impact Statement for Reconfiguration of the Nuclear Weapons Complex .

Not Available

1994-06-01

194

Water and Sediment Quality in the Yukon River Basin, Alaska, During Water Year 2005.  

National Technical Information Service (NTIS)

This report contains water-quality and sediment-quality data from samples collected in the Yukon River Basin from March through September during the 2005 water year (WY). Samples were collected throughout the year at five stations in the basin (three on t...

P. F. Schuster

2007-01-01

195

Field Evaluation Of Arsenic Speciation In Sediments At The Ground Water/Surface Water Interface  

EPA Science Inventory

The speciation and mineralogy of sediments contaminated with arsenic at the ground water/surface water interface of the Ft. Devens Super Fund Site in Ft. Devens, MA were determined using X-ray absorption fine structure and X-ray diffraction spectroscopy. Speciation and mineralog...

196

Water and Sediment Quality in the Yukon River Basin, Alaska, During Water Year 2003.  

National Technical Information Service (NTIS)

This report contains water-quality and sediment-quality data from samples collected in the Yukon River basin from March through September during the 2003 water year (WY). Samples were collected throughout the year at five stations in the basin (three on t...

P. F. Schuster

2005-01-01

197

Succession in a microbial community associated with chitin in Lake Erie sediment and water  

SciTech Connect

Slides coated with reprecipitated chitin were buried in Lake Erie sediments under laboratory conditions. Changes in the microbial community on the slide were studied over time, in varying depths of the water and sediment column, and in anaerobic and aerobic zones of the sediment. Bacterial activity in the overlying water was highest after incubation of 2-7 days. Sediment populations were greatest from 7 days (aerobic zone) to 13 days (anaerobic zone). (11 photos, numerous references, 1 table)

Warnes, C.E.; Randles, C.I.

1980-11-01

198

SEDIMENT TOXICITY ASSESSMENT THROUGH EVALUATION OF THE TOXICITY OF INTERSTITIAL WATER  

EPA Science Inventory

The interstitial water toxicity approach is a multiphase procedure for assessing sediment toxicity using interstitial (i.e.. pore) water. he use of pore water for sediment toxicity assessment was based on the strong correlations between contaminant concentrations in pore water an...

199

Risk factors for contamination of domestic hot water systems by Legionellae  

SciTech Connect

To assess risk factors associated with the contamination of the domestic environment by legionellae, 211 houses in the Quebec City area were randomly selected and water samples were collected from the hot water tank, the shower heads, and the most frequently used faucet. After centrifugation, concentrated samples were seeded in triplicate on BCYE and GPV media. Data on the characteristics of the hot water system and plumbing in the house and on the personal habils of the occupants were collected for each house. Among these 211 houses, hot water was provided by either an oil or gas heater in 33 and by an electric heater in 178. Legionellae were isolated from none of the samples from houses with oil or gas heaters and from 39% (69 of 178) of those with electric water heaters. This association remained highly significant after control for water temperature and other variables in a stratified analysis. In the 178 houses with an electric heater, 12% of the faucets, 15% of the shower heads, and 37% of the water heaters were contaminated. Legionella pneumophila serogroups 2 and 4 were the most frequently isolated strains. Logistic regression showed that factors associated with electric water heater contamination were (1) location of the house in older districts of the city (2) old age of the water heater, and (3) low water temperature. Contamination of the water heater was the only factor significantly associated with the contamination of peripheral outlets. This study shows that the presence of an electric heater is strongly associated with contamination of domestic hot water systems by Legionellae. The public health importance of this contamination is still unknown.

Alary, M.; Joly, J.R. (Univ. Laval, Quebec (Canada))

1991-08-01

200

In situ observation of the water-sediment interface in combined sewers, using endoscopy.  

PubMed

A new method for water-sediment interface observation has been designed. This system is based on a small diameter endoscope protected by a graduated plastic tube. It makes it possible to visualise in a non-destructive manner the sediments and the water-sediment interface. The endoscope was used to investigate Le Marais catchment (Paris): an immobile organic layer was observed at the water-sediment interface. This layer appears in pools of gross bed sediment, at the upstream of collectors, in zones where velocity is slow and where bed shear stress is less than 0.03 N/m2. PMID:12666796

Oms, C; Gromaire, M C; Chebbo, G

2003-01-01

201

Metals in the surface sediments of selected water reservoirs, Slovakia.  

PubMed

Ruzin and Velke Kozmalovce water reservoirs (Slovakia) receive potentially toxic elements through rivers draining catchment areas polluted with the former extensive mining of ore-bearing deposits. In this study, the concentrations and fractionation of metals (antimony, arsenic, cadmium, chromium, cobalt, copper, lead, mercury, molybdenum, nickel, vanadium and zinc) have been studied in the surface sediments of the two water reservoirs. Comparison of metal concentrations found in the sediments with the mean shale values revealed a significant anthropogenic enrichment mostly with antimony (22.7), copper (8.5), zinc (5.5), cadmium (4.7), mercury (4.7), arsenic (4.5) and lead (3.9), and antimony (9.8), cadmium (8.8), zinc (4.9), lead (3.3) and arsenic (3.1) in the Ruzin and Velke Kozmalovce reservoirs, respectively. The results of fractionation study showed that the major proportion of cadmium (44.9-52.6%), cobalt (35.7-58.3%) and zinc (27.8-48.7%) was found in labile fractions, i.e., water- and acid-soluble fractions, although copper and nickel exhibited also significant labile fractions. When the risk assessment code was applied to the fractionation study, cadmium and cobalt came under high and very high risk category for the environment, and therefore might cause adverse effect to aquatic life. PMID:20411242

Hiller, Edgar; Jurkovic, Lubomír; Sutriepka, Michal

2010-04-22

202

Partitioning behavior of per- and polyfluoroalkyl compounds between pore water and sediment in two sediment cores from Tokyo Bay, Japan.  

PubMed

The partitioning behavior of per- and polyfluoroalkyl compounds (PFCs) between pore water and sediment in two sediment cores collected from Tokyo Bay, Japan, was investigated. In addition, the fluxes and temporal trends in one dated sediment core were studied. Short-chain perfluoroalkyl carboxylic acids (PFCAs) (C < or = 7) were found exclusively in pore water, while long-chain PFCAs (C > or = 11) were found only in sediment The perfluoroalkyl sulfonates (PFSAs), n-ethylperfluoro-1-octanesulfonamidoacetic acid (N-EtFOSAA), and perfluorooctane sulfonamide (PFOSA) seemed to bind more strongly to sediment than PFCAs. The enrichment of PFCs on sediment increased with increasing organic matter and decreasing pH. The perfluorocarbon chain length and functional group were identified as the dominating parameters that had an influence on the partitioning behavior of the PFCs in sediment The maximum SigmaPFC contamination in sediment was observed in 2001-2002 to be a flux of 197 pg cm(-2) yr(-1). Statistically significant increased concentrations in Tokyo Bay were found for perfluorooctanesulfonate (PFOS) (1956-2008), perfluorononanoic acid (PFNA) (1990-2008), and perfluoroundecanoic acid (PFUnDA) (1990-2008). Concentrations of PFOSA and N-EtFOSAA increased between 1985 and 2001, but after 2001, the concentration decreased significantly, which corresponded with the phase out of perfluorooctyl sulfonyl fluoride-based compounds by the 3M Company in 2000. PMID:19806729

Ahrens, Lutz; Yamashita, Nobuyoshi; Yeung, Leo W Y; Taniyasu, Sachi; Horii, Yuichi; Lam, Paul K S; Ebinghaus, Ralf

2009-09-15

203

Summary report on water quality, sediment and water chemistry data for water and sediment samples collected from source areas to Melton Hill and Watts Bar reservoirs  

SciTech Connect

Contamination of surface water and sediments in the Clinch River and Watts Bar Reservoir (CR/WBR) system as a result of past and present activities by the US Department of Energy (DOE) on the Oak Ridge Reservation (ORR) and also activities by non-ORR facilities are being studied by the Clinch River Environmental Restoration Program (CR-ERP). Previous studies have documented the presence of heavy metals, organics, and radionuclides in the sediments of reservoirs in the vicinity. In support of the CR-ERP, during the summer of 1991, TVA collected and evaluated water and sediment samples from swimming areas and municipal water intakes on Watts Bar Reservoir, Melton Hill Reservoir (which is considered part of the Clinch River and Watts Bar Reservoir System), and Norris Reservoir, which was considered a source of less-contaminated reference or background data. Results of this study indicated that the levels of contamination in the samples from the Watts Bar and Melton Hill Reservoir sites did not pose a threat to human health. Despite the numerous studies, until the current work documented by this report, relatively few sediment or water samples had been collected by the CR-ERP in the immediate vicinity of contaminant point sources. This work focused on water and sediment samples taken from points immediately downstream from suspected effluent point sources both on and off the ORR. In August and September, 1994, TVA sampled surface water and sediment at twelve locations in Melton Hill and Watts Bar Reservoirs. Eleven of the sampling sites were selected based on existence of pollutant discharge permits, known locations of hazardous waste sites, and knowledge of past practices. The twelfth sample site was selected as a relatively less contaminated reference site for comparison purposes.

Tomaszewski, T.M.; Bruggink, D.J.; Nunn, D.L.

1995-08-01

204

Radioactive dating: Studies on ground water and sediments. (Latest citations from the Selected Water Resources Abstracts database). Published Search  

SciTech Connect

The bibliography contains citations concerning radioactive dating of ground water and sediments. Articles discuss ground water movement and recharge; and lake, marine, and glacial sediments. Citations address dating techniques using isotopes of carbon, lead, uranium, radium, and tritium. Studies on sedimentation rate, water quality, aquifer characteristics, geological survey, and glacial history are presented. (Contains a minimum of 103 citations and includes a subject term index and title list.)

Not Available

1994-10-01

205

Calefaccion de Edificos y Agua Caliente para Uso Domestico Mediante Energia Solar (Solar Heating of Building and Domestic Hot Water).  

National Technical Information Service (NTIS)

This report provides guidance in the design and cost analysis of solar heating systems for buildings and domestic hot water (DHW). The nature of solar radiation, several types of solar systems, storage devices, and architectural considerations are among t...

E. J. Beck R. L. Field

1976-01-01

206

Methods using passive sampling techniques in sediment for the estimation of pore water concentrations and available concentrations for hydrophobic contaminants  

Microsoft Academic Search

Hydrophobic contaminants entering the aqueous environment will generally sorb to particulate matter in the water phase and sediment due to their low water solubility. Sediment is often considered as a sink and\\/or buffer for hydrophobic contaminants. The risk of sediment contamination is related to what the sediment can release to the water phase, rather than the total concentration in the

Foppe Smedes

2007-01-01

207

A mathematical model of water and sediment flow in open river channels  

Microsoft Academic Search

A one-dimensional mathematical model of water and sediment flow in open channels is proposed based on the forces influencing\\u000a a water stream and bottom and stream sediments. The equations of water and sediment flow are closed by the equations of continuity\\u000a of stream, velocity of particle motion in a stream, and the equation of balance of kinetic energy and moving

M. V. Shmakova; A. N. Kondrat’ev

2008-01-01

208

Tidal effect on dynamics of pore water nitrate in intertidal sediment of a eutrophic Estuary  

Microsoft Academic Search

To evaluate the effect of the tidal cycle on the pore water nitrate dynamics in intertidal sediment, concentrations of inorganic\\u000a nitrogen in water and sediment were monitored during tidal cycles in the mud flat of Tama Estuary, Japan. During submergence,\\u000a nitrate concentration was highest in the overlying water and decreased monotonically with increasing depth in the sediment,\\u000a suggesting that the

Toshihiro Usui; Isao Koike; Norio Ogura

1998-01-01

209

Metabolism of niclosamide in sediment and water systems  

USGS Publications Warehouse

A series of experiments analyzed the kinetics and mechanisms of [ 14C]niclosamide degradation. The aerobic aquatic metabolism of [ 14C]niclosamide was studied in nonsterile river water/sediment mixtures. Test systems, maintained under aerobic conditions, were treated with niclosamide and incubated in the dark at 25.0 ?? 1.0 ??C for 30 days. Half-lives of 4.9 and 5.4 days were calculated for the chlorosalicylic acid- and chloronitroaniline-labeled test systems, respectively. From 0 to 21 days after treatment (DAT), the only metabolism product observed in either test system was aminoniclosamide. At the final sampling interval, five peaks were resolved from the chlorosalicylic acid label, and three peaks were resolved from the chloronitroaniline label test substance. By 30 DAT, sediment-bound residues represented ???70% of the observed radioactivity. For the anaerobic aquatic metabolism of [14C]niclosamide, test systems were incubated under anaerobic conditions for 365 days. Half-lives of 0.65 day for the chlorosalicylic acid label and 2.79 days for the chloronitroaniline label were calculated. From 0 to 3 DAT, niclosamide was first transformed into aminoniclosamide. Aminoniclosamide is readily formed, as it was observed in the chlorosalicylic acid label 0 DAT sampling. Several minor metabolites were observed in the water and sediment extracts. None of these metabolites were formed to a significant amount until the parent niclosamide dissipated below the detection limit. Two of the byproducts from these metabolism studies are polar unknowns eluting at 3 and 5 min by HPLC, similar to the unknowns observed in aqueous photolysis studies.

Graebing, P. W.; Chib, J. S.; Hubert, T. D.; Gingerich, W. H.

2004-01-01

210

Arsenic resistant microorganisms isolated from agricultural drainage water and evaporation pond sediments  

Microsoft Academic Search

Elevated levels of As in contaminated water and soil could pose a major threat to the environment. Relatively high levels of As have been reported in agricultural drainage water and in evaporation pond sediments in Kern County, California. The objective of this study was to enumerate and isolate As-resistant microorganisms from agricultural drainage water and evaporation pond sediments and to

K. Davis Huysmans; W. T. Frankenberger

1990-01-01

211

EFFECT OF SEDIMENT ON THE FATE OF METOLACHLOR AND ATRAZINE IN SURFACE WATER  

Technology Transfer Automated Retrieval System (TEKTRAN)

Experiments were conducted to determine the persistence of atrazine and metolachlor in surface water, and to evaluate the contribution of sediment to their dissipation from surface waters. Atrazine was more persistent than metolachlor in the sediment-free surface water systems. First-order 50% dissi...

212

16. GEOCHEMISTRY OF INTERSTITIAL WATERS AND SEDIMENTS, LEG 64, GULF OF CALIFORNIA 1  

Microsoft Academic Search

Studies of interstitial waters obtained from DSDP Leg 64 drill sites in the Gulf of California have revealed informa- tion both on early diagenetic processes in the sediments resulting from the breakdown of organic matter and on hydro- thermal interactions between sediments and hot doleritic sill intrusions into the sediments. In all the sites drilled sulfate reduction occurred as a

Joris M. Gieskes; Henry Elderfield; James R. Lawrence; Jeff Johnson; Barbara Meyers; Andrew Campbell

213

Alternate bar transformation due to change of water discharge in graded and uniform sediment beds  

Microsoft Academic Search

Transformation process of alternate bars and variations in flow depth and sediment transport rate due to periodic change in water discharge are investigated on the basis of flume tests using the uniform sediment and the graded sediment. Experimental results show that the transformation process of alternate bars is influenced by the wave period strongly. That is, an effect of the

Hiroshi Miwa; Jun Yokogawa; Atsuyuki Daido

214

Bioavailability of lambda-cyhalothrin to Chironomus riparius in sediment–water and water-only systems  

Microsoft Academic Search

The bioavailability of 14C-lambda-cyhalothrin and its bioconcentration by larvae of the aquatic insect Chironomus riparius was studied in laboratory sediment–water systems. Ten different sediments with a range of physico-chemical characteristics were investigated. The chemical was applied to sediment slurries and fourth instar C. riparius were exposed in the test system for 48h. The distribution of the chemical between the sediment,

M. J Hamer; U. M Goggin; K Muller; S. J Maund

1999-01-01

215

Exploring the Links between Immigration, Ageing and Domestic Water Consumption: The Case of the Metropolitan Area of Barcelona  

Microsoft Academic Search

March H., Perarnau J. and Saurí D. Exploring the links between immigration, ageing and domestic water consumption: the case of the Metropolitan Area of Barcelona, Regional Studies. Mediterranean urban environments are increasingly undergoing structural or temporary episodes of water stress, which may lead to decreases in the use of water. Taking the Metropolitan Area of Barcelona (MAB) as a case

Hug March; Judit Perarnau; David Saurí

2012-01-01

216

Exploring the Links between Immigration, Ageing and Domestic Water Consumption: The Case of the Metropolitan Area of Barcelona  

Microsoft Academic Search

March H., Perarnau J. and Saurí D. Exploring the links between immigration, ageing and domestic water consumption: the case of the Metropolitan Area of Barcelona, Regional Studies. Mediterranean urban environments are increasingly undergoing structural or temporary episodes of water stress, which may lead to decreases in the use of water. Taking the Metropolitan Area of Barcelona (MAB) as a case

Hug March; Judit Perarnau; David Saurí

2010-01-01

217

Experimental and modeling studies on thermosiphon domestic solar water heaters with flat-plate collectors at clear nights  

Microsoft Academic Search

To investigate effects of water temperature in the storage tank and height difference between collector loop connections at the tank on freeze protection of flat-plate collectors at clear nights in terms of outlet water temperature of the thermosiphonic reverse flow from the collector (referred to as Tout), two sets of thermosiphon domestic solar water heaters (DSWH, in short) were constructed

Runsheng Tang; Yanbin Cheng; Maogang Wu; Zhimin Li; Yamei Yu

2010-01-01

218

Field Observations of Hydrodynamics, Sediment Transport, and Water and Sediment Quality in the Hudson-Raritan Estuary  

Microsoft Academic Search

The New York-New Jersey Harbor estuary system is of enormous ecological and economic importance to the region. The presence of toxic chemicals in the water and sediments results in reduced water quality, fisheries restrictions\\/advisories, and general adverse impacts to the estuarine ecosystem. The Port of New York and New Jersey is central to the economy of the region. However, in

M. S. Bruno; S. Glenn; R. Chant; K. Rankin; G. Korfiatis; N. Dimou; E. Creed; B. Fullerton; A. Pence; P. Burke; C. Haldeman; R. Hires; E. Hunter

2002-01-01

219

Animal-Sediment Interactions Relevant to Shallow-Water Boundary-Layer Flows and Sediment Transport.  

National Technical Information Service (NTIS)

The long-term goals of this research are to identify conditions where existing abiotic, sediment-transport models would make reasonably accurate predictions, and to identify the key, biologically relevant parameters that would improve sediment-transport m...

C. A. Butman

1998-01-01

220

Estimating suspended sediment concentrations in surface waters of the Amazon River wetlands from Landsat images  

SciTech Connect

A method has been developed, based on spectral mixture analysis, to estimate the concentration of suspended sediment in surface waters of the Amazon River wetlands from Landsat MSS and TM images. Endmembers were derived from laboratory reflectance measurements of water-sediment mixtures with a range of sediment concentrations. Using these references spectra, the authors applied a linear mixture analysis to multispectral images after accounting for instrument and atmosphere gains and offsets. Sediment concentrations were estimated for individual pixels from the mixture analysis results based on a nonlinear calibration curve relating laboratory sediment concentrations and reflectance to endmember fractions. The uncertainty in the sediment concentrations derived from this analysis for three Amazon images is predicted to be within [plus minus] 20 mg/L, and the concentrations fall within a range of concentrations of suspended sediment that were measured at several times and places in the field over the past 15 years. The emphasis of their work is to use the patterns of sediment concentrations to compute the approximate volumes of sediment that are transferred between the main channel and floodplain of the Amazon River. However, the methodology can be applied universally if the optical properties of water and sediment at the site are known, and it is, therefore, useful for the study of suspended sediment concentrations in surface waters of wetlands elsewhere.

Mertes, L.A.K.; Smith, M.O.; Adams, J.B. (Univ. of Washington, Seattle (United States))

1993-03-01

221

Influence of water solubility, phase equilibria, and capillary pressure on methane occurrence in sediments  

SciTech Connect

Microbial methane is generated in rapidly accumulating marine sediments (>40 m/my) where pore waters are deficient in dissolved oxygen and sulfate. Based on indirect geochemical evidence, microbial methane generation is largely confined to depths of between 10 and 1000 meters beneath the sea floor. Under shelf conditions (water depth <200 m), methane concentrations can exceed solubility in pore water and accumulate as free gas, or escape the sediment as bubbles, or be oxidized in surface sediments. Under some deeper-water conditions of continental slope and rise sediments, more of the methane can be retained and buried because of increased solubility, and because methane in excess of solubility can be stabilized as methane hydrate. Few direct measurements of methane concentration in subsurface pore waters have been made. However, methane-water phase transitions (gas-water contacts, base of gas hydrate reflector) on seismic records can be used with methane solubility relationships to estimate gas contents of sediments. Comparison of various environments shows a relatively narrow range of dissolved methane contents. In marine sediments, free gas (and methane hydrate) is stable only in contact with methane-saturated pore water. Finer-grained sediments can be supersaturated with respect to a gas (and gas hydrate ) phase because of capillary pressure inhibition of bubble (or hydrate ) formation. The amount of methane dissolved in marine sediment pore water is necessarily larger than that present as gas hydrate.

Claypool, G.E. (Mobil Technology Co., Dallas, TX (United States))

1996-01-01

222

Numerical modelling of sediment-bacteria interaction processes in surface waters.  

PubMed

Faecal bacteria exist in both free-living and attached forms in surface waters. The deposition of sediments can take faecal bacteria out of the water column and to the bed. The sediments can subsequently be re-suspended into the water column, which can then lead to the re-suspension of the faecal bacteria of the attached form back into the water column, where it may desorb from the sediments. Therefore, the fate and transport of faecal bacteria is highly related to the governing sediment transport processes, particularly where these processes are significant. However, little attempt has been made to model such processes in terms of predicting the impact of the sediment fluxes on faecal bacteria levels. Details are given of the refinement of a numerical model of faecal bacteria transport, where the sediment transport processes are significant. This model is based on the model DIVAST (Depth Integrated Velocities And Solute Transport). Analytical solutions for steady and uniform flow conditions were derived and used to test the sediment-bacteria interaction model. After testing the sediment-bacteria interaction model favourably against known results, the model was then set up for idealized case studies to investigate the effects of sediment on bacteria concentrations in the water column. Finally the model was applied to a simplified artificial flooding study to investigate the impact of suspended sediment fluxes on the corresponding bacteria transport processes. The model predictions have proved to be encouraging, with the results being compared to field measurements. PMID:21256533

Gao, Guanghai; Falconer, Roger A; Lin, Binliang

2011-01-08

223

Sedimentation of Free and Attached Cryptosporidium Oocysts and Giardia Cysts in Water  

PubMed Central

Experimental analysis of the sedimentation velocity of Cryptosporidium parvum oocysts and Giardia lamblia cysts was compared with mathematical description of their sedimentation velocities by using measurements of (oo)cyst size and density and the density and viscosity of the sedimentation medium to determine if the sedimentation kinetics of freely suspended oocysts of C. parvum and cysts of G. lamblia can be described by Stokes’ law. The theoretically calculated sedimentation kinetics showed a good agreement with the experimentally observed kinetics. Both showed a decline in sedimentation velocity over time, caused primarily by variation in (oo)cyst density. The initial apparent sedimentation velocities in Hanks balanced salt solution at 23°C was 0.35 ?m · s?1 for oocysts and 1.4 ?m · s?1 for cysts. (Oo)cysts that enter the surface water environment by discharges of biologically treated sewage may be attached to sewage particles, and this will affect their sedimentation kinetics. Therefore, (oo)cysts were mixed with settled secondary effluent. (Oo)cysts readily attached to the (biological) particles in effluent; 30% of both cysts and oocysts attached during the first minutes of mixing, and this fraction increased to approximately 75% after 24 h. The sedimentation velocity of (oo)cysts attached to secondary effluent particles increased with particle size and was (already in the smallest size fraction [1 to 40 ?m]) determined by the sedimentation kinetics of the effluent particles. The observed sedimentation velocities of freely suspended (oo)cysts are probably too low to cause significant sedimentation in surface water or reservoirs. However, since a significant proportion of both cysts and oocysts attached readily to organic biological particles in secondary effluent, sedimentation of attached (oo)cysts after discharge into surface water will probably be a significant factor in the environmental ecology of C. parvum and G. lamblia. Attachment to particles influences not only sedimentation of (oo)cysts in surface water but also their behavior in drinking water treatment processes.

Medema, G. J.; Schets, F. M.; Teunis, P. F. M.; Havelaar, A. H.

1998-01-01

224

The influence of chironomus plumosus larvae on the exchange of dissolved substances between sediment and water  

Microsoft Academic Search

4th instar Chironomus plumosus larvae (about 1000·m-2) were added to tubes containing sediment and overlying water. At a temperature of 20°C the larvae greatly increased the trasnport of silica, phosphorus and iron from the sediment to the water. Oxygen concentrations did not influence the exchange of silica. For two non-calcareous sediments the exchange of phosphorus and iron was much higher

Wilhelm Granéli

1979-01-01

225

Water quality in a rural river environment: distribution of metals among water and sediment compartments  

NASA Astrophysics Data System (ADS)

Sediments have a significant influence on water quality, owing to their role both as a sink and a potential source of pollutants. In fluvial environments from mountainous catchments, the dynamics of sediment particles and particle-bound contaminants are still poorly understood. As stated by Symader et al. (2007), bottom sediments of small rivers in mountainous areas behave like a transport system of its own and show high temporal variation in their chemical composition. The transport of significant sedimentary loads, as suspended matter, in short periods of time, mainly in winter, poses some issues concerning monitoring and modelling approaches of the transport and fate of micro-pollutants at the catchment scale. On one hand, high stream-flow velocity peaks make it difficult or impossible to maintain suspended sediment samplers fixed in the river channel. On the other hand, the cycle of deposition and re-suspension of finer material, throughout the hydrological year, leads to temporal changes of sediment properties. Our contribution reports some results of an investigation on the water quality in a mountainous rural meso-scale catchment, located in the NE of Portugal. The study integrates the examination of metal contents in the sediments and the water body. The river-bottom sediments and water were simply collected in a planned sampling network, in two different periods of the hydrological year (high and low flow). The finer and most recently deposited sediment was preferentially sampled, and the <63µm granulometric class analysed for the potentially bioavailable fraction. Three metals were considered to illustrate the observations resulting from the combination of data on its dissolved and particulate contents. These are Cu, Pb and Zn, which show similar spatial and temporal distributions at the catchment scale. In the main streams a general increase of metal contents in the potentially bioavailable fraction is observed downstream. The residual fraction decreases in high-energetic sites of the drainage network. No simultaneous variation trends in the metal contents in the water and in the sediment fractions studied are observed. The transport mechanisms and the exchange of material exert a joint influence. Regarding the possible origin of the considered elements we observe peaks of contents in sites influenced by geological mineralisation and urban effluents. The influence of agricultural practices in the fluvial environment quality is more noticeable in the zones of the basin where small agricultural fields, in narrow terraces, are inter-related with urban settlements. In the valleys the impact is lower; the soil layer is thicker and the topography is smoother, attenuating the superficial transport and higher retention of these metals in soils. The results show that the pollutant dispersion and transport in mountainous fluvial environments is governed by multiple interrelated factors difficult to control over time, and predictive models still need better information about the processes governing the transport into and within the fluvial network. The regular monitoring of bed sediments in this kind of basins is important to give some insight into the micro-pollutant transport in small mountainous catchments with an impact on the quality of receiving waters. Symader, W.; Bierl R.; Kurtenbach, A.; Krein, A. (2007). Transport Indicators. In: Sediment Dynamics and Pollutant Mobility in Rivers (eds Westrich, B. & Forstner, U.), pp. 269-304, Springer.

Reis, A.; Parker, A.; Alencoao, A.

2009-04-01

226

Solar Residential Heating and Cooling Field Test Program. Volume 1. Domestic hot water systems. Final report  

SciTech Connect

The Electric Power Research Institute sponsored a field test program to develop information on the operating characteristics and performance of load-managed solar hot water systems in typical single-family homes. Field demonstrations were conducted in three houses built and occupied under the program: two in Albuquerque, New Mexico, and a third on Long Island in New York. The houses were equipped with a variety of experimental domestic hot water systems which were instrumented and monitored over a two-year test period ending in 1981. Load management was accomplished by the storage of thermal energy in tanks of water. Arthur D. Little, Inc., the overall project manager for EPRI, collected and reduced the data and performed a series of analyses that addressed issues of concern to electric utilities, including: Reduction in peak-period electricity demand achieved by the experimental systems, Changes in off-peak and total electricity consumption, Ability of the storage systems to meet water heating requirements, Efficient utilization of stored energy, and Standby heat losses. The results from the domestic water heater test program showed that, generaally, load-managed solar systems were reliable and could be used effectively to shift peak-period electrical loads. Savings in total electricity consumption were also achieved by the solar energy collection systems, without adverse effects from the load-management feature. Standby losses from storage were found to be considerable, as were off-peak power demands. Data from the field tests were used to help reformulate and successfully validate computer simulation models that had been developed in earlier phases of the project. The validated models were then run to simulate a variety of water heater systems, including some not covered by the test program.

Swanson, J.L.; Balasubramaniam, T.A.; Burke, J.C.; Merriam, R.L.; O'Farrell, P.M.; Osborn, W.C.; Rancatore, R.J.

1985-01-01

227

Effect of hydrogen sulfide on phosphorus lability in lake sediments amended with drinking water treatment residuals.  

PubMed

The use of drinking water treatment residuals (WTRs) to immobilize P in sediments is a novel approach for lake restoration. However, the lability of P in WTRs-amended sediments may vary with many factors, e.g., hydrogen sulfide content. Earlier works in our laboratory have demonstrated that WTRs are effective sorbents for hydrogen sulfide in water. Thus, we hypothesized that the lability of P in WTRs-amended sediments would not be increased by hydrogen sulfide. The results of this work suggested that this hypothesis was tenable. Compared to the raw sediments, the amended sediments had significantly lower P desorption potential in the presence of hydrogen sulfide at different times, pH and concentrations. Moreover, the amended sediments were also better able to adsorb hydrogen sulfide. In the amended sediments, the P, which was easily desorbed due to the effect of hydrogen sulfide, was transformed into the Fe/Al bound P. PMID:23453604

Wang, Changhui; Liu, Juanfeng; Pei, Yuansheng

2013-03-01

228

Historical and Hypothetical Future Sedimentation and Water Storage in Kajakai Reservoir, Central Afghanistan  

USGS Publications Warehouse

SUMMARY Sedimentation has reduced water storage in Kajakai Reservoir. If current sedimentation rates continue, hypothetical future reservoir water volumes at the spillway elevation of 1,033.5 meters could be reduced about 22 percent from 2006 to 2057. Even if the spillway elevation is raised to 1,045 meters, a severe drought could result in large multiyear irrigation-supply deficits in which reservoir water levels remain below 1,022 meters for more than 4 years. Hypothetical climate change and sedimentation could result in greater water-supply deficits. The chance of having sufficient water supplies in Kajakai Reservoir during the worst month is about 47 percent.

Vining, Kevin C.; Vecchia, Aldo V.

2008-01-01

229

Improving water quality in agricultural catchments: sediment and nutrient retention in field wetlands  

NASA Astrophysics Data System (ADS)

A recent update of Water Framework Directive classifications in the UK indicates that only 28% of water bodies currently achieve good ecological status and that agriculture is one of the main sectors responsible for the pressures contributed by sediment and nutrients. The use of edge-of-field features, such as field wetlands - small sediment and pollutant trapping features (

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

2012-04-01

230

Control of water erosion and sediment in open cut coal mines in tropical areas  

Microsoft Academic Search

The purpose is to reduce the environmental impacts from open cut mining in tropical areas, such as Indonesia and Vietnam. Research conducted on methods for the control of water erosion and sediment from open cut coal mines is described. Data were collected on climate and weathering in tropical areas, mechanism of water erosion and sedimentation, characteristics of rocks in coal

T. Ueda; C. Nugraha; K. Matsui; H. Shimada; M. Ichinose; J. Gottfried

2005-01-01

231

The study of PAC-coagulation sedimentation-UF process for treating micro-polluted water  

Microsoft Academic Search

A process of powdered activated carbon?ƒ PAC?? - coagulation sedimentation - Ultrafiltration?ƒ UF ?? was used to investigate the effect of removing organic matter in micro- polluted water. The results showed that the PAC-coagulation sedimentation - UF combined process could remove effectively dissolved organic matter in micro-polluted water. After pre- dosing 15mg \\/ L PAC, the whole removal of CODMn,

Tao Lin; Liang Li; Wei Chen

2011-01-01

232

Molecular weight distribution of dissolved organic carbon in marine sediment pore waters  

Microsoft Academic Search

The molecular weight distribution of dissolved organic carbon (DOC) in pore waters from estuarine and continental margin sediments was examined using ultrafiltration techniques. The majority of this pore water DOC (?60–90%) had a molecular weight less than 3 kDa. This percentage appeared to vary systematically among the different sediments studied and showed very slight changes with depth (upper ?30 cm).

David J Burdige; Kip G Gardner

1998-01-01

233

Petroleum hydrocarbons in water and sediments of northwest Arabian Gulf 1980–2005  

Microsoft Academic Search

A survey has been conducted to evaluate pollution by petroleum hydrocarbons (PHC's) in water, sediments and living organisms of southern Iraqi sectors represented by Shatt Al-Arab River, Khor Al-Zubair, Umm Qasser, Khor Abdullah and the northwest Arabian Gulf. Petroleum hydrocarbons in water as dissolved and particulate, in sediments as exchangeable and residual and in the organs of living organisms were

Faris J. M. Al-Imarah; Abass A. Hantoosh; Ali M. Nasir

2007-01-01

234

Hexachlorobenzene Uptake by Fathead Minnows and Macroinvertebrates in Recirculating Sediment/Water Systems.  

National Technical Information Service (NTIS)

Fathead minnow (Pimephales promelas), the worm, Lumbriculus variegatus, and the amphipods Hyalella azteca and Gammarus lacustris were exposed to hexachlorobenzene (HCB) in water with and without a bed of HCB-spiked sediment. Water HCB concentrations were ...

G. S. Schuytema D. F. Krawczyk W. L. Griffis A. V. Nebeker M. L. Robideaux

1990-01-01

235

Effect of Temperature and Dissolved Oxygen on Sediment-Water Nutrient Flux.  

National Technical Information Service (NTIS)

A series of experiments was conducted to determine the influence of water-column temperature and dissolved oxygen on sediment-water nutrient flux. Three nutrients were considered: ammonium nitrogen, nitrate nitrogen, and ortho phosphorus. Results of the e...

C. F. Cerco

1985-01-01

236

Bacterial magnetite produced in water column dominates lake sediment mineral magnetism: Lake Ely, USA  

NASA Astrophysics Data System (ADS)

Environmental magnetic studies of annually laminated sediments from Lake Ely, northeastern Pennsylvania, USA indicate that bacterial magnetite is the dominant magnetic mineral in the lake sediment. In previous studies of Lake Ely sediment, the dark, organic-rich layers in the annual laminae were interpreted to have high-intensity saturation isothermal remanent magnetizations (SIRMs) while the light-coloured, silt-rich layers have low-intensity SIRMs. To test the hypothesis that the magnetic grains in the sediments were an authigenic product of magnetotactic bacteria rather than detrital magnetic grains eroded from the watershed, we analysed samples from the water column, the lake sediment, and a sediment trap installed near the lake bottom. Direct microscopic observation of the water column samples showed the presence of magnetotactic bacteria in and below the oxic-anoxic transition zone (OATZ). To characterize the magnetic minerals, rock magnetic parameters were measured for material from the water column, the sediment trap and the dark- and light-coloured lake sediments. Low-temperature magnetic measurements tested for the presence of magnetosomes in separated dark- and light-coloured layer samples. Numeric unmixing of the low-temperature results showed that biogenic magnetites were present in the lake sediment and contributed more significantly to the SIRM in the dark, organic-rich layers than in the light-coloured, inorganic silt-rich layers. Observations under the transmission electron microscope (TEM) of magnetic extracts also show the abundance of magnetosomes in the lake sediment. The presence of live magnetotactic bacteria in the water column and the predominance of bacterial magnetites in filtered particulate matter, sediment traps and recent lake sediment all suggest that bacterial magnetites are the main magnetic minerals in Lake Ely sediment. This finding suggests that changes in environmental factors that control the productivity of magnetic bacteria in the lake likely contribute to the variability of magnetic mineral concentrations observed in the lake sediments.

Kim, BangYeon; Kodama, Kenneth P.; Moeller, Robert E.

2005-10-01

237

IMPORTANCE OF SEDIMENT RESEARCH IN GLOBAL WATER SYSTEM SCIENCE  

Microsoft Academic Search

The global production of suspended sediments to discharge into the ocean is estimated about 20 × 10 9 t·y -1 , of which over 25% may be trapped by about 45,000 large dams constructed around the world. Both sediment production and reservoir trapping are increasing. Sediment production, transport, deposition and its temporal and spatial balance have a major impact on

Kuniyoshi TAKEUCHI

2004-01-01

238

Nano-porous pottery using calcined waste sediment from tap water production as an additive.  

PubMed

A suspension of sediment from a lagoon in a tap water production plant was collected for this experiment. The suspension was spray dried and calcined at 700 °C for 1 h. After calcining, 30 wt.% of the sediment were mixed with pottery clay. Samples with and without calcined sediment were sintered at 900, 1000 and 1100 °C. The results show that calcined sediment can be used as an additive in pottery clay. The samples with calcined sediment show higher porosity, water absorption and flexural strength, especially for 900 and 1000 °C. At 900 °C, samples with calcined sediment show a porosity of 50% with an average pore size of 68 nm, water absorption of 31% and flexural strength of 12.61 MPa. PMID:19942644

Sangsuk, Supin; Khunthon, Srichalai; Nilpairach, Siriphan

2009-11-26

239

Applying Ra isotopes to measure water exchange rates in permeable sediments  

NASA Astrophysics Data System (ADS)

In the coastal ocean, waves and currents generate pressure gradients at the seafloor, which drive a circulation of seawater through sandy seafloor sediments. Biological activity in the sediments converts inflowing organic matter and oxidants into CO2 and nutrients, which are returned to the water column. To evaluate the impact of benthic organic matter cycling on ocean chemistry, the fluid flow rate through permeable sediments must be known. At Huntington Beach, CA, between the shoreline and 3 km offshore, we have collected sediment cores and in situ pore waters. Samples were analyzed for oxygen, nutrients, and four naturally-occurring radioisotopes: 222Rn, 223Ra, 224Ra, and 228Ra. We have calculated fluid circulation rates within sediments using a reaction- transport model of the radioisotope pore water distributions. Pore waters in the top 25-55 cm of sediments were flushed every 4-10 days. 228Ra profiles identified slower exchange that occurred deeper in the sediments. Dissolved 228Ra increased with depth in sediments and accounted for a significant fraction of the pore water 224Ra. The resulting 224Ra emanation gradient must be included in models to accurately calculate the irrigation rate. 223Ra profiles were similar to 224Ra profiles, suggesting a similar relationship with 227Ac. The irrigation rate can then be applied to the pore water distribution of nutrients to calculate the flux of nutrients returned to the water column and estimate the supply of organic carbon to the seafloor.

Colbert, S. L.; Hammond, D. E.

2007-12-01

240

Factors Affecting Domestic Water Consumption in Rural Households upon Access to Improved Water Supply: Insights from the Wei River Basin, China.  

PubMed

Comprehensively understanding water consumption behavior is necessary to design efficient and effective water use strategies. Despite global efforts to identify the factors that affect domestic water consumption, those related to domestic water use in rural regions have not been sufficiently studied, particularly in villages that have gained access to improved water supply. To address this gap, we investigated 247 households in eight villages in the Wei River Basin where three types of improved water supply systems are implemented. Results show that domestic water consumption in liters per capita per day was significantly correlated with water supply pattern and vegetable garden area, and significantly negatively correlated with family size and age of household head. Traditional hygiene habits, use of water appliances, and preference for vegetable gardening remain dominant behaviors in the villages with access to improved water supply. Future studies on rural domestic water consumption should pay more attention to user lifestyles (water appliance usage habits, outdoor water use) and cultural backgrounds (age, education). PMID:23977190

Fan, Liangxin; Liu, Guobin; Wang, Fei; Geissen, Violette; Ritsema, Coen J

2013-08-16

241

The potential source of dissolved aluminum from resuspended sediments to the North Atlantic deep water  

SciTech Connect

Laboratory and field studies were conducted to investigate the significance of resuspended sediments as a source of dissolved Al to the deep northwest Atlantic. Sediment resuspension experiments demonstrate the effect on dissolved Al concentration (initially 11 nM) of adding natural suspended sediments (ca. 0.1-10 mg/L) to seawater. The concentration of dissolved Al increased by the resuspension of sediments; for example, addition of 0.15 mg/L sediments caused dissolved Al to increase by 10 nM. Distributions of dissolved and leachable particulate Al off the tail of the Grand Banks, near the high-energy western boundary current, show elevated levels in the near-bottom waters. The authors suggest that resuspended sediments associated with nepheloid layers along the western boundary of the North Atlantic are a source of dissolved Al. Strong western boundary currents provide the energy to resuspend and maintain intense nepheloid layers of sediments. Continued resuspension and deposition of sediments within the nepheloid layer promotes the release of Al from sediments to the overlying water. The Al-rich terrigenous sediments that predominate along the deep boundary of the Denmark Strait, Labrador Sea, Newfoundland and off Nova Scotia constitute a potentially significant source of dissolved Al. Release of Al from resuspended sediments associated with nepheloid layers at a more northern location (e.g., Denmark Strait) may contribute to the near-linear increase in dissolved Al with depth observed in the deep northwest Atlantic.

Moran, S.B.; Moore, R.M. (Dalhousie Univ., Halifax, Nova Scotia (Canada))

1991-10-01

242

Microbial contamination of contact lens storage cases and domestic tap water of contact lens wearers.  

PubMed

Contact lenses have been widely used as an alternative to spectacles both in developed and developing countries. However, under certain circumstances, adverse responses can occur during contact lens wear and several microorganisms--including bacteria, fungi, and free living amoebae--can cause several eye infections in wearers. Extended wear of contact lenses is the major risk factor of eye infections such as microbial keratitis, besides contaminated contact lens storage case, contaminated lens care solutions, and inaccurate contact lens handling. In this study, we collected contact lens storage case and domestic tap water samples from 50 asymptomatic contact lens wearers. We determined that total aerobic mesophilic bacteria were isolated in 45 (90 %), Gram negative rod bacteria were isolated in 20 (40 %), Pseudomonas spp. were isolated in 2 (4 %) and fungi were isolated in 18 (36 %) out of 50 contact lens storage cases. Free living amoebae were not detected in investigated contact lens storage cases. At the same time, out of 50, total aerobic mesophilic bacteria were isolated in 34 (68 %), fungi were isolated in 15 (30 %) and free living amoebae were isolated in 15 (30 %) domestic tap water samples. No Gram-negative rod bacteria and Pseudomonas spp. were detected in investigated water samples. Two contact lens case samples and two tap water samples were excluded from the analysis for Pseudomonas spp. for technical reasons. According to our findings, inadequate contact lens maintenance during lens wear may result in the contamination of contact lens storage cases. This situation can lead to severe eye infections in contact lens wearers over time. PMID:23064864

Üstüntürk, Miray; Zeybek, Zuhal

2012-10-13

243

Influence of Intermittent and Continuous Modes of Water Supply on Domestic Water Consumption  

Microsoft Academic Search

In developing countries, water distribution systems are designed for continuous water supply (CWS) with peak factor between\\u000a 2.0 and 3.0. While in practice, water is supplied for restricted hours in the morning and evening hours for various reasons.\\u000a One of the assumption is that under intermittent water supply (IWS), water consumption in residential areas is less compared\\u000a to CWS. A

Subhash P. Andey; Prakash S. Kelkar

2009-01-01

244

Sediment contact tests as a tool for the assessment of sediment quality in German waters.  

PubMed

A sediment contact test (SCT) battery consisting of five ecotoxicological test systems was applied to 21 native freshwater sediments characterized by a broad variety of geochemical properties and anthropogenic contamination. Higher plants (Myriophyllum aquaticum), nematodes (Caenorhabditis elegans), oligochaetes (Lumbriculus variegatus), zebrafish embryos (Danio rerio), and bacteria (Arthrobacter globiformis), representing various trophic levels and exposure pathways, were used as test organisms. The test battery detected sediment toxicity caused by anthropogenic pollution, whereas the various tests provided site-specific, nonredundant information to the overall toxicity assessment. Based on the toxicity pattern derived from the test battery, the sediments were classified according to a newly proposed classification system for sediment toxicity assessment. The SCT-derived classification generally agreed well with the application of consensus-based sediment quality guidelines (SQGs), especially with regard to sediments with high toxic potential. For sediments with low to medium toxic potential, the SQGs often underestimated the toxicity that was detected by the SCTs, underpinning the need for toxicity tests in sediment quality assessment. PMID:23027525

Feiler, Ute; Höss, Sebastian; Ahlf, Wolfgang; Gilberg, Daniel; Hammers-Wirtz, Monika; Hollert, Henner; Meller, Michael; Neumann-Hensel, Helga; Ottermanns, Richard; Seiler, Thomas-Benjamin; Spira, Denise; Heininger, Peter

2012-11-21

245

Investigation of magnetotaxis of magnetotactic bacteria in water and sediment  

NASA Astrophysics Data System (ADS)

Magnetotactic bacteria contain chains of magnetic particles which allow them to align and move along the magnetic field to search for optimal habitats in chemically stratified environments. This phenomenon is known as magnetotaxis. The alignment is passive, and driven by the torque m-B between the magnetic dipole m of the chain and the external magnetic field B. The alignment is counteracted by the randomizing effect of Brownian motion, and the average alignment of free bacteria in water, expressed by cos(?), where ? is the angle between m and B, is expected to follow the Langevin law cos(?) = L(mB/kT) where k is the Boltzmann constant and T the absolute temperature [Frankel, 1980]. This law implies that a minimum strength for the Earth's field is required for a bacterium with given magnetic moment to have a certain alignment with the field. The resulting motion is a biased random walk whose "efficiency" for a displacement along B is equal to the average aligmnent. Calculated values for cos(?) in the present Earth's field give good alignments >0.9. Direct experimental observations of the Langevin law on living bacteria in various field intensity are limited to one study by [Kalmijn, 1981]. Here we report systematic observations for two types of wild-type bacteria: magnetic cocci containing two to five chains of ~100 magnetosomes, and magnetobacterium Bavaricum , a rod-shaped bacterium containing several hundreds magnetosomes [Hanzlik et al., 1996]. We also investigated the aligment of those bacteria in natural sediment, where physical constraints imposed by the pore volume are expected to have a great influence on their capability of to align with an external field. Our results show that the alignment of free swimming magnetotactic bacteria in water obeys Langevin's law, with >0.8 alignments in external fields of 3?T for Bavaricum and 30?T for big cocci (the present earth's field is at avrage 50?T). This result shows that magnetotactic bacteria, and in particular Bavaricum, synthesize more than 10 times magnetosomes than they need for magnetotaxis in present field. This fact could leat to the suggestion that magnetosomes could have other unknown functions besides navigation in a magnetic field. On the other hand, typical sedimentary environments pose drastically different conditions for magnetotaxis. This is shown by our measurements of bacteria's alignment in acquaria containing natural lake sediments. Because direct observation of bacteria in sediment is not possible, we applied strong pulsed magnetic field to reverse the magnetic moment of bacteria whose magnetic moment forms a >90° angle to the pulse field. These bacteria become South-seeking and can be counted. By applying pulses along different directions with respect to the external field it is possible to calculate their alignment from the ratio between North- and South seeking. Our results indicate that the bacteria's alignment in sediment is

Mao, X.; Egli, R.

2012-04-01

246

Ecological impacts of lead mining on Ozark streams: Toxicity of sediment and pore water  

USGS Publications Warehouse

We studied the toxicity of sediments downstream of lead-zinc mining areas in southeast Missouri, using chronic sediment toxicity tests with the amphipod, Hyalella azteca, and pore-water toxicity tests with the daphnid, Ceriodaphnia dubia. Tests conducted in 2002 documented reduced survival of amphipods in stream sediments collected near mining areas and reduced survival and reproduction of daphnids in most pore waters tested. Additional amphipod tests conducted in 2004 documented significant toxic effects of sediments from three streams downstream of mining areas: Strother Creek, West Fork Black River, and Bee Fork. Greatest toxicity occurred in sediments from a 6-km reach of upper Strother Creek, but significant toxic effects occurred in sediments collected at least 14 km downstream of mining in all three watersheds. Toxic effects were significantly correlated with metal concentrations (nickel, zinc, cadmium, and lead) in sediments and pore waters and were generally consistent with predictions of metal toxicity risks based on sediment quality guidelines, although ammonia and manganese may also have contributed to toxicity at a few sites. Responses of amphipods in sediment toxicity tests were significantly correlated with characteristics of benthic invertebrate communities in study streams. These results indicate that toxicity of metals associated with sediments contributes to adverse ecological effects in streams draining the Viburnum Trend mining district.

Besser, J. M.; Brumbaugh, W. G.; Allert, A. L.; Poulton, B. C.; Schmitt, C. J.; Ingersoll, C. G.

2009-01-01

247

Control of water erosion and sediment in open cut coal mines in tropical areas  

SciTech Connect

The purpose is to reduce the environmental impacts from open cut mining in tropical areas, such as Indonesia and Vietnam. Research conducted on methods for the control of water erosion and sediment from open cut coal mines is described. Data were collected on climate and weathering in tropical areas, mechanism of water erosion and sedimentation, characteristics of rocks in coal measures under wet conditions, water management at pits and haul roads and ramps, and construction of waste dumps and water management. The results will be applied to the optimum control and management of erosion and sediments in open cut mining. 6 refs., 8 figs.

Ueda, T.; Nugraha, C.; Matsui, K.; Shimada, H.; Ichinose, M.; Gottfried, J. [Kyushu University, Fukuoka (Japan). Department of Earth Resources Engineering

2005-07-01

248

Polycyclic aromatic hydrocarbons in sediments, pore water and the amphipod Pontoporeia hoyi form Lake Michigan  

SciTech Connect

Polycyclic aromatic hydrocarbon (PAH) concentrations were measured in Pontoporeia hoyi, the most abundant benthic organism in Lake Michigan, and in its associated sediment/pore water matrix. Individual PAH concentrations ranged from 10 ppb to 1 ppm in three sedimentary environments having different levels of organic carbon. Pore water concentrations appeared to be independent of sediment concentration. P. hoyi bioconcentration factors ranged from approximately 10/sup 4/ to 10/sup 5/ for seven analyzed PAHs. A major fraction of the phenanthrene, fluoranthene and pyrene in P. hoyi appears to come from sediments and pore water, while chrysene and BaP are primarily obtained from water.

Eadie, B.J.; Landrum, P.F.; Faust, W.

1982-01-01

249

Chemistry of calcium carbonate-rich shallow water sediments in the Bahamas  

SciTech Connect

The geochemistry of calcium carbonate-rich sediments from a variety of environments throughout the Bahamas was investigated with particular emphasis on the factors that control the pore water chemistry. Most sediments are supersaturated with respect to aragonite, the most abundant carbonate component. Experimental studies indicate that the observed in situ calcium carbonate ion activity products can often be produced as reversible metastable equilibria between the sediments and seawater. This is interpreted as being the result of interactions between the solutions and the minor high Mg-calcite component present in these sediments. Although the overlying waters are more supersaturated than the pore waters, carbonate dissolution, not precipitation, dominates in these sediments as a result of organic matter oxidation and the resulting increase in P/sub CO/sub 2//. The carbonate sediments of the Bahamas are remarkable for their purity, with the exception of special environments such as mangrove swamps and tidal flats with algal mats. Organic matter and heavy metal content is extremely low. Only minor sulfate reduction is occurring in most sediments. Phosphate is undetectable in all pore waters, probably as a result of adsorption on carbonate mineral surfaces. Other dissolved pore water components such as ammonia and DOC are much lower than typically found in shallow water fine-grained terrigeneous sediments.

Morse, J.W.; Zullig, J.J.; Bernstein, L.D.; Millero, F.J.; Milne, P.; Mucci, A.; Choppin, G.R.

1985-02-01

250

234U and 238U isotopes in water and sediments of the southern Baltic.  

PubMed

The aim of this work was to determine the concentration of 234U and 238U and calculate the values of the 234U/238U activity ratio in waters and sediments from the various regions of the southern Baltic Sea: Gda?sk Deep, S?upsk Narrow and Bornholm Deep. The concentration of uranium in analysed sediments from southern Baltic increase with core depth to what probably is connected with diffusion from sediments to water through interstitial water, where uranium concentration is much higher than in bottom water. The highest concentrations of uranium were observed in sediments of S?upsk Narrow (0.66-7.11 mg kg(-1) d.w.) and S?upsk Bank (0.61-6.93 mg kg(-1) d.w.), the lowest in sediments from Bornholm Deep (0.54-3.77 mg kg(-1) d.w.). The 234U/238U activity ratio results indicated that the sedimentation of terrigenic material and Vistula River transport are the general sources of uranium in the southern Baltic sediments. The value of 234U/238U activity ratio in sediments from reduction areas from southern Baltic (Gda?sk Deep and Bornholm Deep) indicated that reduction process of U(VI) to U(IV) and removing of anthropogenic uranium from seawater to sediments constitutes a small part only in Gda?sk Deep. PMID:14689997

Skwarzec, B; Bory?o, A; Strumi?ska, D

2002-01-01

251

Summary report on water quality, sediment and water chemistry data for water and sediment samples collected from source areas to Melton Hill and Watts Bar reservoirs  

Microsoft Academic Search

Contamination of surface water and sediments in the Clinch River and Watts Bar Reservoir (CR\\/WBR) system as a result of past and present activities by the US Department of Energy (DOE) on the Oak Ridge Reservation (ORR) and also activities by non-ORR facilities are being studied by the Clinch River Environmental Restoration Program (CR-ERP). Previous studies have documented the presence

T. M. Tomaszewski; D. J. Bruggink; D. L. Nunn

1995-01-01

252

Report on water quality, sediment and water chemistry data for water and sediment samples collected from source areas to Melton Hill and Watts Bar reservoirs  

Microsoft Academic Search

Contamination of surface water and sediments in the Clinch River and Watts Bar Reservoir (CR\\/WBR) system as a result of past and present activities by the US Department of Energy (DOE) on the Oak Ridge Reservation (ORR) and also activities by non-ORR facilities are being studied by the Clinch River Environmental Restoration Program (CR-ERP). Previous studies have documented the presence

T. M. Tomaszewski; D. J. Bruggink; D. L. Nunn

1995-01-01

253

Biogeochemical malfunctioning in sediments beneath a deep-water fish farm.  

PubMed

We investigated the environmental impact of a deep water fish farm (190 m). Despite deep water and low water currents, sediments underneath the farm were heavily enriched with organic matter, resulting in stimulated biogeochemical cycling. During the first 7 months of the production cycle benthic fluxes were stimulated >29 times for CO(2) and O(2) and >2000 times for NH(4)(+), when compared to the reference site. During the final 11 months, however, benthic fluxes decreased despite increasing sedimentation. Investigations of microbial mineralization revealed that the sediment metabolic capacity was exceeded, which resulted in inhibited microbial mineralization due to negative feed-backs from accumulation of various solutes in pore water. Conclusions are that (1) deep water sediments at 8 °C can metabolize fish farm waste corresponding to 407 and 29 mmol m(-2) d(-1) POC and TN, respectively, and (2) siting fish farms at deep water sites is not a universal solution for reducing benthic impacts. PMID:22763326

Valdemarsen, Thomas; Bannister, Raymond J; Hansen, Pia K; Holmer, Marianne; Ervik, Arne

2012-07-02

254

Sediments, porewaters and diagenesis in an urban water body, Salford, UK: impacts of remediation  

NASA Astrophysics Data System (ADS)

Contaminated sediments deposited within urban water bodies commonly exert a significant negative effect on overlying water quality. However, our understanding of the processes operating within such anthropogenic sediments is currently poor. This paper describes the nature of the sediment and early diagenetic reactions in a highly polluted major urban water body (the Salford Quays of the Manchester Ship Canal) that has undergone remediation focused on the water column.The style of sedimentation within Salford Quays has been significantly changed as a result of remediation of the water column. Pre-remediation sediments are composed of a range of natural detrital grains, predominantly quartz and clay, and anthropogenic detrital material dominated by industrial furnace-derived metal-rich slag grains. Post-remediation sediments are composed of predominantly autochthonous material, including siliceous algal remains and clays. At the top of the pre-remediation sediments and immediately beneath the post-remediation sediments is a layer significantly enriched in furnace-derived slag grains, input into the basin as a result of site clearance prior to water-column remediation. These grains contain a high level of metals, resulting in a significantly enhanced metal concentration in the sediments at this depth.Porewater analysis reveals the importance of both bacterial organic matter oxidation reactions and the dissolution of industrial grains upon the mobility of nutrient and chemical species within Salford Quays. Minor release of iron and manganese at shallow depths is likely to be taking place as a result of bacterial Fe(III) and Mn(IV) reduction. Petrographic analysis reveals that the abundant authigenic mineral within the sediment is manganese-rich vivianite, and thus Fe(II) and Mn(II) released by bacterial reactions may be being taken up through the precipitation of this mineral. Significant porewater peaks in iron, manganese and silicon deeper in the sediment column are most probably the result of dissolution of furnace-derived grains in the sediments. These species have subsequently diffused into porewater above and below the metal-enriched layer.This study illustrates that the remediation of water quality in anthropogenic water bodies can significantly impact upon the physical and chemical nature of sedimentation. Additionally, it also highlights how diagenetic processes in sediments derived from anthropogenic grains can be markedly different from those in sediments derived from natural detrital material.

Taylor, Kevin G.; Boyd, Nathan A.; Boult, Stephen

2003-07-01

255

Pilot-scale study of efficient coagulation sedimentation of micro-polluted water  

Microsoft Academic Search

This pilot-scale study is based on an efficient coagulation sedimentation process technology used for micro-polluted water treatment of Beijing-Hangzhou Grand Canal(BHGC). The best coagulant among PAC, Al2(SO4)3 and FeCl3 and its optimal dosage were studied in coagulation sedimentation jar test. The best coagulant was PAC, and its optimal dosage was 40 mg\\/L. The coagulation sedimentation jar test showed that the

Liang Shen; Li Cheng; Heli Wang; Xinying Lian; Jingxian Qi

2010-01-01

256

Natural and Human-Induced Variations in Water and Sediment Runoff in the Danube River Mouth  

Microsoft Academic Search

Long-term natural and human-induced variations in water and sediment runoff in the Danube Delta head were studied on the basis of analysis of an extremely long series of observations (1840–2002). A considerable reduction of sediment runoff in the second half of the 20th century related to sediment accumulation in reservoirs was revealed. It was found that human activities had an

E. A. Levashova; V. N. Mikhailov; M. V. Mikhailova; V. N. Morozov

2004-01-01

257

Distribution of Total Mercury and Methyl Mercury in Water, Sediment, and Fish from South Florida Estuaries  

Microsoft Academic Search

.   Concentrations of total mercury and methyl mercury were determined in sediment and fish collected from estuarine waters\\u000a of Florida to understand their distribution and partitioning. Total mercury concentrations in sediments ranged from 1 to 219\\u000a ng\\/g dry wt. Methyl mercury accounted for, on average, 0.77% of total mercury in sediment. Methyl mercury concentrations were\\u000a not correlated with total mercury

K. Kannan; R. F. Lee; H. L. Windom; P. T. Heitmuller; J. M. Macauley; J. K. Summers

1998-01-01

258

The domestication of water: water management in the ancient world and its prehistoric origins in the Jordan Valley.  

PubMed

The ancient civilizations were dependent upon sophisticated systems of water management. The hydraulic engineering works found in ancient Angkor (ninth to thirteenth century AD), the Aztec city of Tenochtitlan (thirteenth to fifteenth century AD), Byzantine Constantinople (fourth to sixth century AD) and Nabatean Petra (sixth century BC to AD 106) are particularly striking because each of these is in localities of the world that are once again facing a water crisis. Without water management, such ancient cities would never have emerged, nor would the urban communities and towns from which they developed. Indeed, the 'domestication' of water marked a key turning point in the cultural trajectory of each region of the world where state societies developed. This is illustrated by examining the prehistory of water management in the Jordan Valley, identifying the later Neolithic (approx. 8300-6500 years ago) as a key period when significant investment in water management occurred, laying the foundation for the development of the first urban communities of the Early Bronze Age. PMID:20956370

Mithen, Steven

2010-11-28

259

Nitrogen dynamics in sediment during water level manipulation on the Upper Mississippi River  

USGS Publications Warehouse

Nitrogen (N) has been linked to increasing eutrophication in the Gulf of Mexico and as a result there is increased interest in managing and improving water quality in the Mississippi River system. Water level reductions, or 'drawdowns', are being used more frequently in large river impoundments to improve vegetation growth and sediment compaction. We selected two areas of the Upper Mississippi River system (Navigation Pool 8 and Swan Lake) to examine the effects of water level drawdown on N dynamics. Navigation Pool 8 experienced summer drawdowns in 2001 and 2002. Certain areas of Swan Lake have been drawn down annually since the early 1970s where as other areas have remained inundated. In the 2002 Pool 8 study we determined the effects of sediment drying and rewetting resulting from water level drawdown on (1) patterns of sediment nitrification and denitrification and (2) concentrations of sediment and surface water total N (TN), nitrate, and ammonium (NH4+). In 2001, we only examined sediment NH4+ and TN. In the Swan Lake study, we determined the long-term effects of water level drawdowns on concentrations of sediment NH4+ and TN in sediments that dried annually and those that remained inundated. Sediment NH4+ decreased significantly in the Pool 8 studies during periods of desiccation, although there were no consistent trends in nitrification and denitrification or a reduction in total sediment N. Ammonium in sediments that have dried annually in Swan Lake appeared lower but was not significantly different from sediments that remain wet. The reduction in sediment NH4+ in parts of Pool 8 was likely a result of increased plant growth and N assimilation, which is then redeposited back to the sediment surface upon plant senescence. Similarly, the Swan Lake study suggested that drawdowns do not result in long term reduction in sediment N. Water level drawdowns may actually reduce water retention time and river-floodplain connectivity, while promoting significant accumulation of organic N. These results indicate that water level drawdowns are probably not an effective means of removing N from the Upper Mississippi River system.

Cavanaugh, Jennifer C.; Richardson, William B.; Strauss, Eric A.; Bartsch, Lynn A.

2006-01-01

260

Levels of PAHs in the waters, sediments, and shrimps of Estero de Urias, an estuary in Mexico, and their toxicological effects.  

PubMed

PAHs were measured in water, sediment, and shrimps of Estero de Urias, an estuary in Sinaloa, Mexico, during the rainy and dry seasons, and analyzed for eleven PAHs routinely detected in samples. Phenanthrene was the most dominant congener in the water, sediment, and shrimp samples comprising about 38, 24, and 25%, respectively, of the eleven PAHs detected, followed by pyrene and naphthalene in water and sediment samples, and pyrene and fluorine in the shrimp samples. Total PAH concentrations ranged from 9 to 347?ng/L in water, 27 to 418?ng/g in sediments, and 36 to 498?ng/g in shrimps. The sources of contamination are closely related to human activities such as domestic and industrial discharge, automobile exhausts, and street runoff. High concentrations were also measured during the rainy season and during the first quarter of the year. Toxicity tests were also carried out, exposing fish embryos and juvenile shrimps to some of these PAHs. Fish embryos exposed to PAHs showed exogastrulation, while juvenile shrimps showed significantly lower growth rates than controls. DNA and protein alterations were also observed. These toxicity tests indicate that PAH concentrations measured could be dangerous to some aquatic organisms, particularly during early stages of development. PMID:22997501

Jaward, Foday M; Alegria, Henry A; Galindo Reyes, Jose G; Hoare, Armando

2012-09-10

261

The Role of Non-Conventional and Lower Quality Water for the Satisfaction of the Domestic Needs in Drought Management Plans  

Microsoft Academic Search

This chapter outlines the potential and role that underground low quality water and non conventional water (recycled grey\\u000a water, desalinated and domestic effluent water), have and can play in the preparation of drought mitigation plans especially\\u000a in relation to the satisfaction of the domestic water supply needs. Low quality underground water, if available in aquifers\\u000a within the city or village

Nicos X. Tsiourtis

262

Integration of Pseudomonas aeruginosa and Legionella pneumophila in drinking water biofilms grown on domestic plumbing materials.  

PubMed

Drinking water biofilms were grown on coupons of plumbing materials, including ethylene-propylene-diene-monomer (EPDM) rubber, silane cross-linked polyethylene (PE-X b), electron-ray cross-linked PE (PE-X c) and copper under constant flow-through of cold tap water. After 14 days, the biofilms were spiked with Pseudomonas aeruginosa, Legionella pneumophila and Enterobacter nimipressuralis (10(6) cells/mL each). The test bacteria were environmental isolates from contamination events in drinking water systems. After static incubation for 24 h, water flow was resumed and continued for 4 weeks. Total cell count and heterotrophic plate count (HPC) of biofilms were monitored, and P. aeruginosa, L. pneumophila and E. nimipressuralis were quantified, using standard culture-based methods or culture-independent fluorescence in situ hybridization (FISH). After 14 days total cell counts and HPC values were highest on EPDM followed by the plastic materials and copper. P. aeruginosa and L. pneumophila became incorporated into drinking water biofilms and were capable to persist in biofilms on EPDM and PE-X materials for several weeks, while copper biofilms were colonized only by L. pneumophila in low culturable numbers. E. nimipressuralis was not detected in any of the biofilms. Application of the FISH method often yielded orders of magnitude higher levels of P. aeruginosa and L. pneumophila than culture methods. These observations indicate that drinking water biofilms grown under cold water conditions on domestic plumbing materials, especially EPDM and PE-X in the present study, can be a reservoir for P. aeruginosa and L. pneumophila that persist in these habitats mostly in a viable but non-culturable state. PMID:20556878

Moritz, Miriam M; Flemming, Hans-Curt; Wingender, Jost

2010-06-01

263

Impact of recycling filter backwash water on organic removal in coagulation–sedimentation processes  

Microsoft Academic Search

The overall purpose of this research was to examine the impacts of filter backwash water (FBWW) and membrane backwash water (MBWW) recycles on water quality in coagulation–sedimentation processes. Specifically, the impact of recycling 5 or 10% by volume of FBWW and MBWW with surface water on the removal of natural organic matter (NOM) was evaluated at bench-scale using a standard

A. Gottfried; A. D. Shepard; K. Hardiman; M. E. Walsh

2008-01-01

264

Phytoremediation facilitates removal of nitrogen and phosphorus from eutrophicated water and release from sediment.  

PubMed

Phosphorus (P) fractions and the effect of phytoremediation on nitrogen and phosphorus removal from eutrophicated water and release from sediment were investigated in the eco-remediation experiment enclosures installed in the Hua-jia-chi pond (Hangzhou city, Zhejiang province, China). The main P fraction in the sediment was inorganic phosphorus (IP). For the mesotrophic sediments, IP mainly consisted of HCl-extractable P (Ca-P). The annual-average concentration of total nitrogen (TN), total phosphorus (TP) in water and the content of TN, TP in different vertical depth of sediment in the experiment enclosures with hydrophyte were always much lower than those in the control enclosure without hydrophyte and those outside of experiment enclosures. It is suggested that phytoremediation was an effective technology for N and P removal from eutrophicated water and release from sediment. PMID:18841488

Xiang, Wu; Xiao-E, Yang; Rengel, Zed

2008-10-08

265

Toxicity tests of effluents with marsh plants in water and sediment  

SciTech Connect

Methods are described for toxicity testing of water and sediment with two varieties of the freshwater marsh plant Echinochloa crusgalli (Linneaus) Palisot de Beauvois (Poaceae), and complex effluents. Two tests are described: a seed germination and early seedling growth test in water, and a survival and seedling growth test in natural and synthetic sediments. Effects of effluents from a sewage treatment plant, tannery, textile mill, pulp and paper mill, coking plant and sewage treatment plant included inhibition of germination, chlorophyll synthesis and growth. The tests with rooted marsh plants were sensitive to pollutants and detected toxicity of a range of pollutants in water and sediment. Synthetic sediments similar to natural sediments allowed toxicity tests to be done under carefully controlled conditions of particle size distribution, organic content, pH, electrode potential (Eh) and cation exchange capacity (CEC).

Walsh, G.E.; Weber, D.E.; Simon, T.L.; Brashers, L.K.

1991-01-01

266

Exergetic modeling and assessment of solar assisted domestic hot water tank integrated ground-source heat pump systems for residences  

Microsoft Academic Search

The present study deals with the exergetic modeling and performance evaluation of solar assisted domestic hot water tank integrated ground-source heat pump (GSHP) systems for residences for the first time to the best of the author's knowledge. The model is applied to a system, which mainly consists of (i) a water-to-water heat pump unit (ii) a ground heat exchanger system

Arif Hepbasli

2007-01-01

267

[Effects of waste water sediments on the levels of heavy metals ion the soil and plants].  

PubMed

Field small-plot experiments studied the effects of sediments of waste water from Saransk disposal systems. The content of toxic heavy metals (lead, arsenic, and cadmium) in the waste-water sediments, was shown to be not greater than their maximum permissible concentrations (32, 2, and 10 mg per kg of dried soil, respectively). With the use of waste-water sediments, the content of manganese, copper, tin, nickel, vanadium, beryllium, cobalt, iron, and chromium was found to correspond to their baseline level in the soil and plants. PMID:15141618

Siniagina, N A; Sul'din, B V; Tumanov, A N; Chetvergov, E V

268

Occurrence of perfluorinated compounds in water and sediment of L’Albufera Natural Park (València, Spain)  

Microsoft Academic Search

Purpose  Perfluorinated compounds (PFCs) are widely distributed from industrialized to remote locations throughout the world. This\\u000a study demonstrates the spatial distributions of PFCs in water and sediments from the L’Albufera Natural Park (Valencia, Spain).\\u000a \\u000a \\u000a \\u000a \\u000a Methods  Grab water and sediment samples were collected. PFCs were extracted from sediments with acidified acetonitrile by ultrasonication\\u000a and cleaned up by solid-phase extraction (SPE) and from water

Yolanda Pico; Cristina Blasco; Marinella Farré; Damia Barceló

269

Efficiency of fluorescence in situ hybridization for bacterial cell identification in temporary river sediments with contrasting water content  

Microsoft Academic Search

We studied the efficiency of two hybridization techniques for the analysis of benthic bacterial community composition under varying sediment water content. Microcosms were set up with sediments from four European temporary rivers. Wet sediments were dried, and dry sediments were artificially rewetted. The percentage of bacterial cells detected by fluorescence in situ hybridization with fluorescently monolabeled probes (FISH) significantly increased

Stefano Fazia; Stefano Amalfitano; Ilaria Pizzetti; Jakob Pernthaler

2007-01-01

270

Influence of the water content on X-ray fluorescence core-scanning measurements in soft marine sediments  

Microsoft Academic Search

The X-ray fluorescence (XRF) core scanner provides bulk-sediment chemistry data measured nondestructively at the split core sediment surface. Although this method is widely accepted, there is little known about the effects of physical properties such as density and water content on XRF core scanner data. Comparison of XRF scanner measurements from the sediment surface and dry powder samples of sediment

Rik Tjallingii; Ursula Röhl; Martin Kölling; Torsten Bickert

2007-01-01

271

Predicting the toxicity of metal-spiked laboratory sediments using acid-volatile sulfide and interstitial water normalizations  

Microsoft Academic Search

Numerous studies have shown that dry weight concentrations of metals in sediments cannot be used to predict toxicity across sediments. However, several studies using sediments from both freshwater and saltwater have shown that interstitial water concentration or normalization involving acid-volatile sulfide (AVS) can be used to predict toxicity in sediments contaminated with cadmium, copper, nickel, lead, or zinc across a

W. J. Berry; D. J. Hansen; W. S. Boothman; J. D. Mahony; D. L. Robson; D. M. di Toro; B. P. Shipley; B. Rogers; J. M. Corbin

1996-01-01

272

Analysis of space heating and domestic hot water systems for energy-efficient residential buildings  

SciTech Connect

An analysis of the best ways of meeting the space heating and domestic hot water (DHW) needs of new energy-efficient houses with very low requirements for space heat is provided. The DHW load is about equal to the space heating load in such houses in northern climates. The equipment options which should be considered are discussed, including new equipment recently introduced in the market. It is concluded that the first consideration in selecting systems for energy-efficient houses should be identification of the air moving needs of the house for heat distribution, heat storage, ventilation, and ventilative cooling. This is followed, in order, by selection of the most appropriate distribution system, the heating appliances and controls, and the preferred energy source, gas, oil, or electricity.

Dennehy, G

1983-04-01

273

Modelling nutrient exchange at the sediment water interface of river systems  

NASA Astrophysics Data System (ADS)

In-stream benthic processes can play a significant role on the water quality of overlying waters flowing through a river network. In order to better understand and quantify the fate of nutrients (nitrogen, phosphorus and silica) during their travel through the river continuum, a deterministic benthic sub-model was developed with the purpose of being connected to a drainage network model. This benthic sub-model resolves the differential equations representing early diagenesis in the sediment, linking the sedimentation rate of organic matter onto the sediment to the resulting flux of nutrients across the sediment water interface. The model has been developed for conditions where sedimentation prevails as well as for situations where net erosion prevents the built-up of a significant sediment layer and where only a biofilm can develop, attached to solid substrates. The benthic model was tested independently of the main water column biological hydrological model to which it is intended to be coupled. For this, three case studies were chosen from the literature representing various sedimentation/erosion conditions: the 8th order river Seine (France), the water storage basin of Méry s/Oise (France), and the headwater stream Orneau (Belgium). The general benthic model has been validated for ammonium, nitrate, oxygen and phosphorus fluxes across the sediment water interface. The capability of the model to correctly predict the observed nutrients profiles within the sediment was also validated for organic carbon, ammonium and phosphorus. An uncertainty analysis showed that using two modelling objectives (observed fluxes and concentration profiles in the sediment) strongly reduces the uncertainty in parameters calibration. A sensitivity analysis illustrated the complexity of the interacting reactions driving each variable, and justifies the usefulness of the model as a tool for understanding and predicting the behaviour of the benthic compartment of river systems.

Thouvenot, Marie; Billen, Gilles; Garnier, Josette

2007-07-01

274

Geochemical-focusing of manganese in lake sediments — An indicator of deep-water oxygen conditions  

Microsoft Academic Search

The lateral distributions of Mn concentrations in the sediments of two Swiss lakes under varying oxygen conditions have been determined. The comparison of Mn distribution patterns with oxygen in the deep-water provides strong evidence for a geochemical-focusing effect, which is driven by the redox cycle of manganese. Conditions essential for this process to occur are anoxic sediments in contact with

Tobias Schaller; Bernhard Wehrli

1996-01-01

275

Diverted Mississippi River sediment as a potential phosphorus source affecting coastal Louisiana water quality  

Microsoft Academic Search

Mississippi River water and associated sediment are seasonally diverted into Louisiana coastal basins to restore historic hydrologic and salinity regimes and to slow or reverse the widespread wetland loss. More river diversions are planned; however, very little research has been conducted on the potential source of phosphorous (P) of these sediments transported by the Mississippi River into the coastal areas

Wen Zhang; J. R. White; R. D. DeLaune

2012-01-01

276

SURVIVAL OF 'DAPHNIA MAGNA' AND 'HYALELLA AZTECA' IN CADMIUM-SPIKED WATER AND SEDIMENT  

EPA Science Inventory

Freshwater sediments and water were spiked with cadmium (Cd) in the laboratory, and toxicity tests were conducted with the cladoceran Daphnia magna and the amphipod Hyalella azteca to determine if Cd in the sediment would cause increased toxicity. The 48-h LC50 values for Daphnia...

277

Dynamics of indicator bacteria populations in sediment and river water near a combined sewer outfall  

Microsoft Academic Search

Sediments collected throughout the summer of 1991 from a river bed around a combined sewer outfall were found to have geometric mean faecal coliform and faecal streptococci densities ranging between 10?10 g and 10?10 g respectively. During the study period, faecal coliform densities in water samples from the same river reach were several logs lower than in the sediment, but

K. N. Irvine; G. W. Pettibone

1993-01-01

278

Rhizon sampling of porewaters near the sediment-water interface of aquatic systems  

Microsoft Academic Search

Rhizon samplers were originally designed as micro-tensiometers for soil science to sample seepage water in the unsaturated zone. This study shows applications of Rhizons for porewater sampling from sediments in aquatic systems and presents a newly developed Rhizon in situ sampler (RISS). With the inexpensive Rhizon sampling technique, porewater profiles can be sampled with minimum disturbance of both the sediment

Jens Seeberg-Elverfeldt; Michael Schlüter; Tomas Feseker; Martin Kölling

2005-01-01

279

Trace metals in metalliferous sediments, MANOP Site M: interfacial pore water profiles  

Microsoft Academic Search

We present data showing enrichments of metals Mn, Cu, V, Cr, Cd and Ni and dissolved organic matter (DOM) in surficial pore waters, depths < 1 cm, at a metalliferous sediment site in the Pacific. We also present a model of metal release during particulate organic carbon (POC) oxidation and opal dissolution at the sediment-seawater interface. A comparison of measured

D. Heggie; D. Kahn; K. Fischer

1986-01-01

280

A probe for sampling interstitial waters of stream sediments and bog soils  

USGS Publications Warehouse

A probe for sampling interstitial waters of stream sediments and bog soils is described. Samples can be obtained within a stratigraphic interval of 2-3 cm, to a depth of 60-80 cm, and with little or no contamination of the samples by sediment or air. ?? 1974.

Nowlan, G. A.; Carollo, C.

1974-01-01

281

Polychlorinated biphenyls: Accumulation from contaminated sediments and water by the polychaete Nereis diversicolor  

Microsoft Academic Search

Comparisons were made of the accumulation of a polychlorinated biphenyl (PCB) mixture from sediments and from water by the benthic worm Nereis diversicolor. Uptake from sediments was dose-dependent, attaining equilibrium concentration factors of approximately 3 to 4 after 2 months. Subsequent PCB elimination rates were concentration-dependent, with higher initial loss rates evident in the worms containing higher levels of PCBs.

S. W. Fowler; G. G. Polikarpov; D. L. Elder; P. Parsi; J.-P. Villeneuve

1978-01-01

282

DEVELOPING MODEL OF BENTHIC-WATER CONTAMINANT TRANSPORT IN BIOTURBATED SEDIMENT  

EPA Science Inventory

Chemicals entering marine waters are incorporated into distinct compartments and these reservoirs are in exchange with one another. he chemo-dynamic storage compartments in marine systems include sediment to the depth of bioturbation (0-50 cm), suspended sediments, dissolved phas...

283

Dissolution kinetics of biogenic silica from the water column to the sediments  

Microsoft Academic Search

Stirred flow-through experiments were conducted for the first time with planktonic biogenic silica (BSi). We investigated the dissolution kinetics of uncleaned and chemically cleaned BSi collected in ocean surface water, sediment traps, and sediments from the Norwegian Sea, the Southern Ocean, and the Arabian Sea. The solubility at 2°C is rather constant (1000 to 1200 ?M). The dissolution rates are,

Dirk Rickert; Michael Schlüter; Klaus Wallmann

2002-01-01

284

Phosphorus in sediments and pore waters of selected Polish dam reservoirs  

Microsoft Academic Search

This study aimed to examine and explain the spatial distribution of total phosphorus in sediments and orthophosphates in interstitial water in four Polish dam reservoirs with varying hydrological and geochemical characteristics. The results are linked to physicochemical parameters of sediments: organic matter and calcium carbonates content, pH, redox potential and conductivity. In two of the studied reservoirs hydrological dynamics were

Adriana Trojanowska; Piotr Jezierski

2011-01-01

285

Partitioning of Cs137 Between Sediment and Water From the Black Sea  

Microsoft Academic Search

As part of a joint USA\\/USSR Environmental Agreement to determine the distribution and concentration of Chernobyl radioactivity in the northwest Black Sea area, the sediment from eight stations was collected and analyzed to assess the ability of this material to adsorb radiocaesium. Batch tests were conducted in which Cs-137 tracer was added to mixtures of sediment and bottom water, with

M. Fuhrmann; R. Pietrzak; J. Neiheisel; R. Dyer

1992-01-01

286

TDR\\/DMT CHARACTERIZATION OF A RESERVOIR SEDIMENT UNDER WATER  

Microsoft Academic Search

The Shihmen Reservoir, completed in early 1960s, has been an important hydro project in Northern Taiwan. Soil erosion and sediment have been a major concern for the longevity of the reservoir. After a series of typhoons in 2004, the intake valve of the hydro power plant was covered by 10 m of sediment. The power generation has been halted since

An-Bin Huang; Chih-Ping Lin; Chih-Chung Chung

287

Phosphorus Sources for Aquatic Weeds: Water or Sediments?  

Microsoft Academic Search

Nine common species of aquatic macrophytes took all their phosphorus from the sediments when grown in situ in both a mesotrophic and a mildly eutrophic bay. Even under hypertrophic conditions, the sediments contributed an average of 72 percent of all the phosphorus taken up during growth. These experiments unambiguously demonstrate for the first time that submergent macrophytes in nature overwhelmingly

R. Carignan; J. Kalff

1980-01-01

288

AN ASSESSMENT OF USING WATER RECYCLING TO RELEASE WATER FOR NEW DOMESTIC CONSUMERS: INITIAL RESULTS  

Microsoft Academic Search

One of the benefits of recycling water to industry is the opportunity to free existing potable water supplies for new customers. A recycling plant was commissioned in May 2001 in Merebank, Durban. The plant receives effluent from the Durban Southern Wastewater Treatment works and treats it to an acceptable standard for industrial use. However, as with any industrial activity there

S. D. Pillay; E. Friedrich; C. A. Buckley

289

Distribution of bacteria in a domestic hot water system in a Danish apartment building.  

PubMed

Bacterial growth in hot water systems seems to cause problems such as bad odor of the water, skin allergies and increased heat transfer resistance in heating coils. In order to establish a basis for long-term suppression of bacterial growth, we studied the distribution of bacteria in a Danish domestic hot water system. Heterotrophic plate counts (HPC) were measured in both water and biofilm samples from various sampling sites in the system. In hot water samples, where the temperature was 55-60 degrees C, the HPC were 10(3)-10(4)CFU/mL at incubation temperatures of 25 degrees C or 37 degrees C and 10(5)CFU/mL at 55 degrees C or 65 degrees C. In the cold water (10 degrees C) supplying the hot water system, the HPC at 25 degrees C or 37 degrees C was lower than in the hot water, and no bacteria were found after incubation at 55 degrees C or 65 degrees C. HPC constituted from 38% to 84% of the AODC results in hot water but only 2% in cold water, which showed a high ratio of culturable bacteria in hot water. Biofilm samples from the hot water tank and the inner surface of the pipes in the cold and hot water distribution system were collected by specially designed sampling devices, which were exposed in the system for 42 days. The quasi-steady-state number of bacteria in the biofilm, measured as the geometric mean of the HPC obtained between 21 and 42 days, was five-fold higher in the hot water pipe (13x10(5)CFU/cm(2) at 55 degrees C) than in the cold water pipe (2.8x10(5)CFU/cm(2) at 25 degrees C). There was no significant difference between the number of bacteria in the biofilm samples from the top, middle and bottom of the hot water tank, and the number of bacteria in the biofilm counted at 55 degrees C ranged from 0.6x10(4) to 1.7x10(4)CFU/cm(2). The surfaces of the sacrificial aluminum anodes and the heating coils in the hot water tank also contained high bacterial numbers. The measured number of bacteria in water and biofilm samples was related to the dimensions of the hot water system, and calculations showed that the majority of bacteria (72%) were located in the biofilm especially in the distribution system, which accounts for the greatest surface area. Free-living bacteria accounted for 26% and only a minor part of the bacteria were in the sludge in the hot water tank (2%). PMID:14630121

Bagh, Lene Karen; Albrechtsen, Hans Jørgen; Arvin, Erik; Ovesen, Kaj

2004-01-01

290

Distributions of pesticides and organic contaminants between water and suspended sediment, San Francisco Bay, California  

SciTech Connect

Suspended-sediment and water samples were collected from San Francisco Bay in 1991 during low river discharge and after spring rains. All samples were analyzed for organophosphate, carbamate, and organochlorine pesticides; petroleum hydrocarbons; biomarkers; and polynuclear aromatic hydrocarbons. The objective were to determine the concentrations of these contaminants in water and suspended sediment during two different hydrologic conditions and to determine partition coefficients of the contaminants between water and sediment. Concentrations of hydrophobic contaminants, such as polynuclear aromatic hydrocarbons, varied with location of sample collection, riverine discharge, and tidal cycle. Concentrations of hydrophobic contaminants in suspended sediments were highest during low river discharge but became diluted as agricultural soils entered the bay after spring rains. Polynuclear aromatic hydrocarbons defined as dissolved in the water column were not detected. The concentrations sorbed on suspended sediments were variable and were dependent on sediment transport patterns in the bay. In contrast, the relatively hydrophilic organophosphate pesticides, such as chlorpyrifos and diazinon, had a ore uniform concentration in suspended sediment. These pesticides were detected only after spring rains. Most of the measured diazinon, at least 98% for all samples, was in the dissolved phase. Measured partition coefficients for diazinon generally were uniform, which suggest that suspended-sediment concentrations were close to equilibrium with dissolved concentrations. The concentration of diazinon sorbed to suspended sediments, at any given sampling site, was driven primarily by the more abundant solution concentration. The concentrations of diazinon sorbed to suspended sediments, therefore, were independent of the patterns of sediment movement. 27 refs., 5 figs., 4 tabs.

Domagalski, J.L.; Kuivila, K.M. (Department of the Interior, Sacramento, CA (United States))

1993-12-01

291

Installation for treatment of sediments coming from stations for purification of industrial waste water  

SciTech Connect

An installation is disclosed for the treatment of sediment coming from a purification station for industrial waste water. The installation consists of a static furnace incinerator into which sediment is transferred by means of an injector. The injector is made up of an elbow tube connected between the furnace and the sediment, a blast pipe injecting air into the furnace and drawing sediment with it due to the vacuum created by the blasted air flow, and an additional air inlet in the furnace wall, the additional air inlet surrounding the elbow.

Petiot, M.

1980-04-22

292

Remote sensing of suspended sediment water research: principles, methods, and progress  

NASA Astrophysics Data System (ADS)

In this paper, we reviewed the principle, data, methods and steps in suspended sediment research by using remote sensing, summed up some representative models and methods, and analyzes the deficiencies of existing methods. Combined with the recent progress of remote sensing theory and application in water suspended sediment research, we introduced in some data processing methods such as atmospheric correction method, adjacent effect correction, and some intelligence algorithms such as neural networks, genetic algorithms, support vector machines into the suspended sediment inversion research, combined with other geographic information, based on Bayesian theory, we improved the suspended sediment inversion precision, and aim to give references to the related researchers.

Shen, Ping; Zhang, Jing

2011-11-01

293

Radium, thorium, uranium, and ²¹°Pb in deep-sea sediments and sediment pore waters from the North Equatorial Pacific  

Microsoft Academic Search

Determination of radium, thorium, uranium isotopes, and ²¹°Pb in sediments and sediment pore waters from North Equatorial Pacific deep-sea clay-silicous oozes shows that the radium and uranium isotopes are mobile in the pore water. The concentration-depth profiles of radium can be understood in terms of a diagenetic model which takes into account mixing of sediment particles by bioturbation, molecular diffusion

J. K. Cochran; S. Krishnaswami

1980-01-01

294

Application of multi-objective technique in modeling water and sediment flow in river reaches  

NASA Astrophysics Data System (ADS)

Usually water resources problems consist of multiple objectives that may be conflicting and competing in nature. To evaluate optimal water resources system performances often it is required to obtain a compromise solution satisfying several goals and objectives. For example, in the case of multipurpose reservoir operations, a number of conflicting and competing purposes such as supply of water for conservation uses, downstream flood control, hydropower generation and related environmental objectives are to be optimally satisfied. It may be noted that for deriving maximum benefit from conservation uses reservoir storage should be as high as possible; on the other hand to achieve maximum flood control benefits the storage should be kept as low as possible. Since flood control and conservation objectives are conflicting in nature, higher achievement in flood control objective results in lower attainment of the conservation objectives. In other areas of water resources such as, rainfall runoff modeling, water quality problems, watershed management etc often a number of objectives are required to be satisfied to derive optimal system performances. It is known that one prominent cause of soil erosion and runoff generation from a catchment is related to the effect of rainfall over the catchment and thus water and the sediment discharge at a river station are mainly depended on rainfall and the catchment characteristics. Water and sediment discharge for a river section can be considered as two outputs due to a rainfall input over the catchment. To describe sediment and water flow through river reaches usually separate models are used and the model parameters are estimated using single/multiple optimization routines. Since water and sediment flow are effects with a common cause, a new model can be obtained that can quantify and explain both the effects that is, flow of sediment and water in a river course. In the present study, application of multiple objective optimization technique has described in obtaining parameters of the integrated water-sediment flow model. The integrated model needs to be calibrated using both water and sediment data for a river reach and requires separate objective functions to independently match water and sediment flow variations for a station. The integrated model describing two hydrological variables is highly nonlinear with exponential model form and requires efficient algorithm to identify model parameters. Multiple objectives were framed to calibrate the model using water and sediment data and the model parameters were estimated applying non-dominated sorting genetic algorithm (NSGA-II). The proposed model formulations are demonstrated for simulating suspended sediment load and water discharge in the Mississippi River Basin, USA. Results obtained show that an integrated model having multiple objectives can be developed to describe two hydrological variables with satisfactory performances.

Sil, Briti Sundar; Choudhury, Parthasarathi

2010-10-01

295

Mercury cycling between the water column and surface sediments in a contaminated area.  

PubMed

Mercury cycling in the water column and upper sediments of a contaminated area, the Largo do Laranjo, Aveiro (Portugal), was evaluated after determination of reactive and non-reactive mercury concentrations in the water column and pore waters of sediments, collected in several places of this bay. In the water column, reactive mercury concentrations varied between 10 and 37 pmol dm(-3), the highest values being observed near the mercury anthropogenic source. However, reactive mercury was a narrowly constrained fraction of the total mercury, making up only 4-16% of the total, showing evidence of the importance of dissolved organic matter on mercury transport. In sediments, higher concentrations of mercury were also determined near industrial discharges. Results indicate the existence of an equilibrium between solid and liquid phases, determined by solid sediment/pore water distribution coefficients. Much of the mercury present in the solid fraction is associated with organic matter (r=0.837) and iron oxyhydroxides (r=0.919), but as oxides begin to dissolve in reduced sediments and organic matter decays, the adsorbed mercury is released. In fact, the mercury concentrations in pore waters of those contaminated sediments largely exceeded the values determined in the water column. As molecular diffusion may contribute to the dissolved mercury distribution in the overlying water column, this phenomenon was evaluated. However, the pore waters of Largo do Laranjo do not enrich the water column substantially in terms of reactive and non-reactive mercury. In fact, pore waters can contribute only to 0.2% and 0.5% of the reactive and non-reactive mercury present in the water column, respectively, showing that as long as mercury is being incorporated in sediments, it stays in stable forms. PMID:16854448

Ramalhosa, Elsa; Segade, Susana Río; Pereira, Eduarda; Vale, Carlos; Duarte, Armando

2006-07-18

296

Partition of nonpolar organic pollutants from water to soil and sediment organic matters  

USGS Publications Warehouse

The partition coefficients (Koc) of carbon tetrachloride and 1,2-dichlorobenzene between normal soil/sediment organic matter and water have been determined for a large set of soils, bed sediments, and suspended solids from the United States and the People's Republic of China. The Koc values for both solutes are quite invariant either for the soils or for the bed sediments; the values on bed sediments are about twice those on soils. The similarity of Koc values between normal soils and between normal bed sediments suggests that natural organic matters in soils (or sediments) of different geographic origins exhibit comparable polarities and possibly comparable compositions. The results also suggest that the process that converts eroded soils into bed sediments brings about a change in the organic matter property. The difference between soil and sediment Koc values provides a basis for identifying the source of suspended solids in river waters. The very high Koc values observed for some special soils and sediments are diagnostic of severe anthropogenic contamination.

Chiou, C. T.

1995-01-01

297

Suspended-sediment characteristics for the Johnson Creek basin, Oregon, water years 2007-10  

USGS Publications Warehouse

Significant Findings An analysis of suspended-sediment transport in the Johnson Creek basin, Oregon, during water years 2007–10 indicated that: Streamflow characteristics for the 4 years of study were not extremely dry or wet, and represented near-average conditions. Computed average annual suspended-sediment loads were 1,890 and 4,640 tons at the Gresham and Milwaukie stations, respectively. More than 70 percent of suspended-sediment transport in the watershed occurred during the high-flow months of November, December, and January. Less than 10 percent of suspended-sediment transport in the watershed occurred during April–October. About 50 percent of all suspended-sediment load is transported during the highest 1 percent of streamflows. The January 2009 streamflow peak was the third highest in the 70-year record for Johnson Creek. About 50 percent of suspended-sediment transport in water year 2009 occurred in January. The drainage area upstream of the Gresham streamflow-gaging station constitutes about 30 percent of the drainage area at the Milwaukie station, but accounted for about 40 percent of the suspended sediment and 45 percent of the streamflow at the Milwaukie station. On an annual basis, most of the higher sediment yield at the Gresham station, relative to the Milwaukie station, can be explained by the higher streamflow yield at the Gresham station rather than by higher suspended-sediment concentration.

Stonewall, Adam J.; Bragg, Heather M.

2012-01-01

298

Harvesting energy from the marine sediment--water interface.  

PubMed

Pairs of platinum mesh or graphite fiber-based electrodes, one embedded in marine sediment (anode), the other in proximal seawater (cathode), have been used to harvest low-level power from natural, microbe established, voltage gradients at marine sediment-seawater interfaces in laboratory aquaria. The sustained power harvested thus far has been on the order of 0.01 W/m2 of electrode geometric area but is dependent on electrode design, sediment composition, and temperature. It is proposed that the sediment/anode-seawater/cathode configuration constitutes a microbial fuel cell in which power results from the net oxidation of sediment organic matter by dissolved seawater oxygen. Considering typical sediment organic carbon contents, typical fluxes of additional reduced carbon by sedimentation to sea floors < 1,000 m deep, and the proven viability of dissolved seawater oxygen as an oxidant for power generation by seawater batteries, it is calculated that optimized power supplies based on the phenomenon demonstrated here could power oceanographic instruments deployed for routine long-term monitoring operations in the coastal ocean. PMID:11352010

Reimers, C E; Tender, L M; Fertig, S; Wang, W

2001-01-01

299

The transport of fine-grained sediments in shallow waters  

NASA Astrophysics Data System (ADS)

A numerical model of the resuspension, deposition, and transport of fine-grained, cohesive sediments has been developed and applied. An essential part of this model is an accurate and physically realistic description of the sediment bed and the resuspension of the bottom sediments due to physical processes. The description is based on data from recent experimental and field work on fine-grained sediments. Pertinent results from this work have been incorporated into the present model, and as part of the calculation, changes in the resuspension properties of the sediment bed with time due to resuspension, deposition, and compaction can be approximately determined. Vertically integrated differential equations were used to approximate the hydrodynamic and sediment transport equations. A volume integral method was used to derive finite difference equations which are second-order accurate, explicit, and locally conservative. A unique feature of the numerical model is that it can successfully treat conditions at open boundaries where both incoming and outgoing waves or disturbances may be present. The model has been applied to the resuspension, deposition, and transport of fine-grained sediments in (1) the Raisin River, a small polluted stream flowing into Lake Erie; (2) a river flowing into a lake or ocean with a cross-flow; and (3) a time-dependent flow in a simple estuary as affected by tidal currents. The formation of erosional and depositional areas under various conditions is demonstrated.

Ziegler, Carl Kirk; Lick, Wilbert

1988-02-01

300

Sediment load from major rivers into Puget Sound and its adjacent waters  

USGS Publications Warehouse

Each year, an estimated load of 6.5 million tons of sediment is transported by rivers to Puget Sound and its adjacent waters—enough to cover a football field to the height of six Space Needles. This estimated load is highly uncertain because sediment studies and available sediment-load data are sparse and historically limited to specific rivers, short time frames, and a narrow range of hydrologic conditions. The largest sediment loads are carried by rivers with glaciated volcanoes in their headwaters. Research suggests 70 percent of the sediment load delivered to Puget Sound is from rivers and 30 percent is from shoreline erosion, but the magnitude of specific contributions is highly uncertain. Most of a river's sediment load occurs during floods.

Czuba, Jonathan A.; Magirl, Christopher S.; Czuba, Christiana R.; Grossman, Eric E.; Curran, Christopher A.; Gendaszek, Andrew S.; Dinicola, Richard S.

2011-01-01

301

The role of sediments in the phosphorus cycle in Lake Lugano. II. Seasonal and spatial variability of microbiological processes at the sediment-water interface  

Microsoft Academic Search

P, Fe, Mn, and S species were analyzed in water samples from the sediment-water interface collected at four seasonally different times during the course of a year at two sampling sites in the southern basin of Lake Lugano (Lago di Lugano). The results reveal the strong influence of the biogeochemical processes in the sediment on the chemical composition of the

Maja A. Lazzaretti; Kurt W. Hanselmann; Helmut Brandl; Daniel Span; Reinhard Bachofen

1992-01-01

302

Selenium sediment toxicity thresholds and derivation of water quality criteria for freshwater biota of western streams  

SciTech Connect

Waterborne and sediment selenium (Se) data, in conjunction with selected physicochemical parameters, were collected from streams of the middle Arkansas River basin, Colorado, USA, to examine the factors affecting sediment Se accumulation in a lotic environment. An empirical model of dissolved-to-sediment Se transfer in western streams, as an interactive function of sediment organic carbon content, was developed and validated. Sediment Se and associated biological effects data were compiled from the literature, to provide an estimate of sediment Se concentration thresholds that have biological effects. Based on this preliminary analysis, sediment Se concentrations of 2.5 {micro}g/g would be a threshold based on predicted effects and concentrations of 4.0 {micro}g/g would be the observed threshold for dish and wildlife toxicity. The dissolved-to-sediment Se transfer model can be used to translate this type of sediment Se toxicity threshold to a site-specific chronic water-quality standard for western streams based on empirically derived sediment total organic carbon values.

Van Derveer, W.D. [Colorado Springs Utilities, CO (United States). Water Resources Dept.; Canton, S.P. [Chadwick Ecological Consultants, Inc., Littleton, CO (United States)

1997-06-01

303

VISUALIZING THE RELATIONSHIP OF PBTS IN WATER AND SEDIMENT TO RESIDUES IN FISH  

EPA Science Inventory

Bioaccumulation of persistent bioaccumulative toxicants (PBTs) in aquatic organisms results from uptake of the chemicals through several different exposure routes associated with water, sediment, and biota. This paper presents an approach for depicting and interpreting bioaccumul...

304

HEXACHLOROBENZENE UPTAKE BY FATHEAD MINNOWS AND MACRO INVERTEBRATES IN RECIRCULATING SEDIMENT/WATER SYSTEMS  

EPA Science Inventory

Fathead minnow (Pimephales promelas), the worm, Lumbriculus variegatus, and the amphipods Hyalella azteca and Gammarus lacustris were exposed to hexachlorobenzene (HCB) in water with and without a bed of HCB-spiked sediment. ater HCB concentrations were maintained by recirculatio...

305

Oxidation and Acidification of Anaerobic Sediment-Water Systems by Autoclaving.  

National Technical Information Service (NTIS)

An important aspect of studies on the fate of organic pollutants is identification of environmental agents that are responsible for observed degradation reactions. To this end, many studies using natural water, soil, or sediment as a medium rely heavily o...

P. G. Tratnyek N. L. Wolfe

1993-01-01

306

PRECISION OF DIALYSIS (PEEPER) SAMPLING OF CADMIUM IN MARINE SEDIMENT INTERSTITIAL WATER  

EPA Science Inventory

Isolating and analyzing interstitial water (IW) during sediment toxicity tests enables researchers to relate concentrations of contaminants to responses of organisms, particularly when IW is a primary route of exposure to bioavailable contaminants by benthic dwelling organisms. W...

307

Transferable Drug Resistance in Bacteria of Coastal Canal Water and Sediment.  

National Technical Information Service (NTIS)

This study was undertaken to determine the comparative incidence of drug-resistant coliforms and salmonellae in the water and bottom sediments of six coastal canal communities which are used heavily for recreational activities.

S. M. Goyal C. P. Gerba J. L. Melnick

1978-01-01

308

METAL SPECIATION IN SOIL, SEDIMENT, AND WATER SYSTEMS VIA SYNCHROTRON RADIATION RESEARCH  

EPA Science Inventory

Metal contaminated environmental systems (soils, sediments, and water) have challenged researchers for many years. Traditional methods of analysis have employed extraction methods to determine total metal content and define risk based on the premise that as metal concentration in...

309

Development of a standard operating procedure for the collection of pyrethroids in water and sediment matrices  

EPA Science Inventory

Through a Regional Applied Research Effort grant to the United States Geological Survey, Region 9 collaborated with ORD on this project to develop a standard operating procedure for collection of water and sediment samples for pyrethroid analysis. ...

310

30 CFR 77.216-5 - Water, sediment or slurry impoundments and impounding structures; abandonment.  

Code of Federal Regulations, 2013 CFR

This plan shall provide for major slope stability, include a schedule for the plan's implementation and, except as provided in paragraph (b) of this section, contain provisions to preclude the probability of future impoundment of water, sediment, or...

2013-07-01

311

Mercury in Fish, Bed Sediment, and Water from Streams Across the United States, 1998-2005.  

National Technical Information Service (NTIS)

Mercury (Hg) was examined in top-predator fish, bed sediment, and water from streams that spanned regional and national gradients of Hg source strength and other factors thought to influence methylmercury (MeHg) bioaccumulation. Sampled settings include s...

B. C. Scudder D. A. Wentz L. C. Chasar M. E. Brigham N. J. Bauch

2009-01-01

312

TOXICITY TESTS OF EFFLUENTS WITH MARSH PLANTS IN WATER AND SEDIMENT  

EPA Science Inventory

Methods are described for toxicity testing of water and sediment with the rooted marsh plants, Echinochloa crusgalli var. crusgalli and var. zelavensis (freshwater) and Spartina alterniflora (estuarine). ive industrial effluents, a sewage treatment plant effluent and a herbicide ...

313

TRNSYS model of a thermosiphon solar domestic water heater with a horizontal store and mantle heat exchanger  

Microsoft Academic Search

A new TRNSYS model of a solar domestic water heater is presented. It describes a thermosiphon system with a horizontal store and a mantle heat exchanger. The fluid inlet is placed at the top of the annular gap. This new TRNSYS ‘Type’ is developed from the standard Types 45 and 38, with some new features. Results of the new type

A. Carrillo Andrés; J. M. Cejudo López

2002-01-01

314

Domestic hot water consumption and efficiency: Researching consumption and demand in New York City multifamily apartment buildings. Final report  

Microsoft Academic Search

This report combines the results of two research projects sponsored by the New York State Energy Research and Development Authority and conducted by EME Group to study domestic hot water (DHW) in multifamily buildings. Part 1 of the report focuses on DHW consumption and demand in 50 New York City multifamily buildings ranging in size from 20 to 248 units.

W. Loss; E. Neumann; M. McNamara; T. Sahagian; J. Winterson

1997-01-01

315

Temporal dynamics of water and sediment exchanges between the Curuaí floodplain and the Amazon River, Brazil  

NASA Astrophysics Data System (ADS)

The fluvial transport and storage of sediments within channel floodplain systems can act as important sinks of sediments. In this study, we document the role of an Amazonian floodplain (Curuaí) for sediment storage. Located on the right bank of the Amazon River, 900 km upstream of the mouth, the complex system contains more than 30 interconnected lakes linked to the mainstream by permanent and temporary channels. With an open-water area varying between 600 km2 and 2500 km2, it represents ˜13% of the total flooded area of the Amazon River, between Manaus and Óbidos. For the period 2000 2003, daily liquid and solid fluxes exchanged between the floodplain system and the Amazon River were determined using an hydrological model based on a network of gauging, meteorological and sediment monitoring stations and satellite data including radar altimetry data. Sediment accumulation occurs during the five months of the flood rise, from December to April. The export of sediments to the mainstream occurs during the low water stage while depositional processes in lakes and channels are disrupted by the wind induced re-suspension of sediments. The mean average sediment storage calculated varies between 558 and 828 × 103 t yr-1 corresponding to 5.4 (±19%) × 103 t km-1 yr-1 of sediment deposited along the 130 km reach between Juruti and Santarem. This annual storage represents between 41% and 53% of the annual flux of sediments entering this floodplain through the main channels. The associated mean specific sedimentation rate is ˜517 (±23%) t km-2 yr-1 leading to a sediment accretion rate of 1.6 mm yr-1 ± 23%.

Bourgoin, Laurence Maurice; Bonnet, Marie-Paule; Martinez, Jean-Michel; Kosuth, Pascal; Cochonneau, Gerard; Moreira-Turcq, Patricia; Guyot, Jean-Loup; Vauchel, Philippe; Filizola, Naziano; Seyler, Patrick

2007-03-01

316

Arsenic contamination in water, soil, sediment and rice of central India  

Microsoft Academic Search

Arsenic contamination in the environment (i.e. surface, well and tube-well water, soil, sediment and rice samples) of central\\u000a India (i.e. Ambagarh Chauki, Chhattisgarh) is reported. The concentration of the total arsenic in the samples i.e. water (n=64), soil (n=30), sediment (n=27) and rice grain (n=10) were ranged from 15 to 825 ?g L?1, 9 to 390 mg kg?1, 19 to 489 mg

K. S. Patel; K. Shrivas; R. Brandt; N. Jakubowski; W. Corns; P. Hoffmann

2005-01-01

317

Spatial and temporal patterns in sediment and water column nutrients in a eutrophic Southern California estuary  

Microsoft Academic Search

Quarterly field sampling was conducted to characterize variations in water column and sediment nutrients in a eutrophic southern\\u000a California estuary with a history of frequent macroalgal blooms. Water column and sediment nutrient measures demonstrated\\u000a that Upper Newport Bay (UNB) is a highly enriched estuary. High nitrate (NO3\\u000a ?) loads from the river entered the estuary at all sampling times with

Karleen A. Boyle; Krista Kamer; Peggy Fong

2004-01-01

318

Occurrence of ionophore antibiotics in water and sediments of a mixed-landscape watershed  

Microsoft Academic Search

Analytical methods for quantifying three ionophore antibiotics, monensin, salinomycin, and narasin, were developed for water and sediment matrices. Sample preparation was based on solid-phase extraction (SPE) and high-performance liquid chromatography (HPLC) tandem mass spectrometry (MS\\/MS) was used to separate and detect the compounds. Recoveries ranged from 83% to 117% for water and from 51% to 105% for sediment in three

Sung-Chul Kim; Kenneth Carlson

2006-01-01

319

Polychlorinated biphenyl congeners and organochlorine insecticides in the water column and sediments of Daya Bay, China  

Microsoft Academic Search

Samples of sub-surface water, suspended particulate matter (SPM) and surface sediments collected from Daya Bay, China have been analysed for 12 polychlorinated biphenyl (PCB) congeners and 18 organochlorine insecticides, using gas chromatography electron capture detection. Total PCB levels varied from 91.1 to 1355.3 ng l?1 in water and from 0.85 to 27.37 ng g?1 dry weight in sediments. The levels

J. L. Zhou; K. Maskaoui; Y. W. Qiu; H. S. Hong; Z. D. Wang

2001-01-01

320

Sediment-water interactions affect assessments of metals discharges at electric utilities  

Microsoft Academic Search

We present three examples to show the importance of sediment-water interactions to electric utilities: 1) Selenium (Se), in\\u000a ash pond effluents, has caused declines in fish populations in North Carolina. A biogeochernistry model appears to explain\\u000a Se dynamics for several reservoirs. However, further work on sediment water interactions is needed to predict the speed of\\u000a reservoir Se declines following cessation

J. S. Mattice; D. B. Porcella; R. W. Brocksen

1997-01-01

321

Toxicokinetics of fluoranthene to the amphipod, Leptocheirus plumulosus, in water-only and sediment exposures  

Microsoft Academic Search

The ability of the equilibrium partitioning (EqP) and critical body residue (CBR) approaches to predict the toxicity of the polycyclic aromatic hydrocarbon, fluoranthene, to a standard sediment toxicity test organism, the amphipod Leptocheirus plumulosus was examined in a series of water-only and sediment exposures. Concentrations of fluoranthene in water that resulted in 50% mortality (10-d LC50) were 39.2 (35.1–43.8, 95%

Susan B. Kane driscoll; Linda C. Schaffner; Rebecca M. Dickhut

1998-01-01

322

The effect of Lake Erie water level variations on sediment resuspension  

Microsoft Academic Search

Variability in Lake Erie water levels results in variations of the fluid forces applied to the lake bed by free-surface gravity wind-waves. An increase in the bed stress may re-suspend sediment deposited years earlier. This study identifies areas of possible non-cohesive sediment mobilization in response to the forcing conditions and water levels present in Lake Erie. Observations from NOAA buoy

Douglas S. Dusini; Diane L. Foster; Jennifer A. Shore; Carolyn Merry

2009-01-01

323

Determination of pentachlorophenol in water and aquifer sediments by high-performance liquid chromatography  

USGS Publications Warehouse

Methods for the determination of pentachlorophenol (PCP) in water and aquifer sediments are presented. Reverse-phase high-performance liquid chromotography employing ion suppression and gradient elution is used. PCP can be determined directly in water at a lower limit of detection Of 0.2 micrograms per liter. For extracts of sediment, PCP can be determined to a lower limit of 1.0 micrograms per kilogram.

Goerlitz, D. F.

1981-01-01

324

Contribution of ammonia, metals, and nonpolar organic compounds to the toxicity of sediment interstitial water from an Illinois River tributary  

Microsoft Academic Search

Toxicity of Illinois River bulk sediment, sediment interstitial (pore) water and elutriates to the oligochaete Lumbriculus variegatus, fathead minnow (Pimephales promelas) and the amphipod Hyalella azteca was compared to determine the most representative aqueous fraction for toxicity identification evaluation (TIE) studies. Toxicity of pore water corresponded better than elutriates to bulk sediment toxicity. Subsequent TIE procedures conducted with the cladoceran

Mary K. Schubauer-Berigan; Gerald T. Ankley

1991-01-01

325

Variations in stream water and sediment phosphorus among select Ozark catchments.  

PubMed

Stream sediments play a large role in the transport and fate of soluble reactive phosphorus (SRP) in stream ecosystems, and equilibrium P concentrations (EPC 0) of benthic sediments at which P is neither adsorbed nor desorbed are often related to stream water SRP concentrations. This study evaluated (i) the variation among water chemistry and sediment-P interactions among streams draining catchments that varied in the land use; (ii) the relations between SRP concentration, sediment EPC 0, and other measured abiotic factors (e.g., particle size distribution, slope of linear sorption isotherms, etc.) in the stream sediments; and (iii) the use of the traditional Mehlich-3 (M3) soil extraction on stream sediments to elucidate other abiotic factors (e.g, M3P, P saturation ratio, etc.) related to SRP concentration in stream sediments. Stream water and sediments were sampled at 22 selected Ozark streams in northwest Arkansas during fall 2003 and spring 2004. Nitrate-N concentrations in the water column (r = 0.69) and modified P saturation ratios (PSR mod) ) of the benthic sediments (r = 0.79) at the selected streams increased with an increase in percent pasture in the catchments, whereas SRP concentration (r = -0.56) and Mehlich-3-extractable P (M3P) content (r = -0.47) decreased with an increase in the percent forested area. Soluble reactive P concentrations in the stream water were positively correlated to sediment EPC 0 (r = 0.51), although sediment EPC(0) was generally greater than SRP. The M3 soil extraction was useful in identifying abiotic factors related to SRP concentrations in the selected streams, in particular SRP concentrations were positively correlated to M3P contents (r = 0.50) and PSR mod (r = 0.71) of the benthic sediments. Thus, M3P and EPC 0 estimates from stream sediments may be valuable yet simple indicators of whether benthic sediments act as sinks or sources of P in fluvial systems, as well as estimating changes in stream SRP concentrations. PMID:17940273

Haggard, Brian E; Smith, Douglas R; Brye, Kristofor R

2007-10-16

326

Sediment Transport at Density Fronts in Shallow Water.  

National Technical Information Service (NTIS)

The long-term goal of this research is to quantify through observations and modeling how density fronts in shallow estuarine flows impact the mobilization, redistribution, trapping, and deposition of suspended sediments. The specific objectives of this pr...

2008-01-01

327

Sediment Transport at Density Fronts in Shallow Water.  

National Technical Information Service (NTIS)

The goal of this research is to quantify through observations and modeling how density fronts in shallow estuarine flows impact the mobilization, redistribution, trapping, and deposition of suspended sediment. The objectives of this research program are t...

D. K. Ralston

2009-01-01

328

Chloride/bromide and chloride/fluoride ratios of domestic sewage effluents and associated contaminated ground water  

SciTech Connect

To establish geochemical tools for tracing the origin of ground water contamination, the authors examined the variations of Cl/Br and Cl/F (weight) ratios in (1) domestic waste water from the Dan Region Sewage Reclamation Project and from reservoirs in the central coast of Israel; (2) associated contaminated ground water; and (3) pristine ground water from the Mediterranean coastal aquifer of Israel. The data show that supply water, anthropogenic NaCl and fluoridation control the Cl/Br and Cl/F ratios of domestic waste water, and conventional sewage treatment does not affect the anthropogenic inorganic signals. The Cl/Br ratios of ground water contaminated with sewage effluent reflect conservative mixing proportions of sewage and regional ground water components. Sensitivity tests demonstrate that it is possible to detect and distinguish sewage contamination from marine ratios after a sewage contribution of 5 to 15% is mixed with regional ground water. Mixing with Br-enriched fresh water however, would reduce this sensitivity. Since the high Cl/Br signal of sewage effluents is distinguishable from other anthropogenic sources with low Cl/Br ratios and from natural contamination sources, Cl/Br ratios can therefore be a useful inorganic tracer for identification of the origin of contaminated ground water. The Cl/F ratios of sewage-contaminated ground water were higher than those in the original sewage effluent, which suggests retention of fluoride into the aquifer solid phase.

Vengosh, A.; Pankratov, I. [Hydrological Service, Jerusalem (Israel)

1998-09-01

329

Microbial Extracellular Polymeric Substances (EPS) in Fresh Water Sediments  

Microsoft Academic Search

Microbially produced extracellular polymeric substances (EPS) have been linked with many important ecological functions in\\u000a natural sediments; yet, most information has been derived from marine systems. The present paper is the first comprehensive\\u000a study on EPS (i.e., carbohydrates and proteins) dynamics in riverine sediments addressing spatial (six reservoirs and four\\u000a groyne fields across three European rivers), temporal (all seasons in

Sabine Ulrike Gerbersdorf; Bernhard Westrich; David M. Paterson

2009-01-01

330

Toxicity of sediments and pore water from Brunswick Estuary, Georgia  

Microsoft Academic Search

A chlor-alkali plant in Brunswick, Georgia, USA, discharged >2 kg mercury\\/d into a tributary of the Turtle River-Brunswick\\u000a Estuary from 1966 to 1971. Mercury concentrations in sediments collected in 1989 along the tributary near the chlor-alkali\\u000a plant ranged from 1 to 27 ?g\\/g (dry weight), with the highest concentrations found in surface (0–8 cm) sediments of subtidal\\u000a zones in the

Parley V. Winger; Peter J. Lasier; Harvey Geitner

1993-01-01

331

The Determination of Metals in Sediment Pore Waters and in 1N HCl-Extracted Sediments by ICP-MS  

USGS Publications Warehouse

Concentrations of metals in sediment interstitial water (pore water) and those extractable from sediment with weak acids can provide important information about the bioavailability and toxicological effects of such contaminants. The highly variable nature of metal concentrations in these matrices requires instrumentation with the detection limit capability of graphite furnace atomic absorption and the wide dynamic linear range capability of ICP-OES. These criteria are satisfied with ICP-MS instrumentation. We investigated the performance of ICP-MS in the determination of certain metals from these matrices. The results for three metals were compared to those determined by graphite furnace atomic absorption spectroscopy. It was concluded that ICP-MS was an excellent instrumental approach for the determination of metals in these matrices.

May, T. W.; Wiedmeyer, R. H.; Brumbaugh, W. G.; Schmitt, C. J.

1997-01-01

332

Phosphate in Interstitial Waters of Anoxic Sediments: Oxidation Effects during Sampling Procedure.  

PubMed

Oxidation during sampling procedures significantly decreases the inorganic phosphate concentrations of interstitial water rich in iron (II). All sampling and analytical procedures must be carried out in an inert atmosphere. Orthophosphate in the interstitial water of Cheaspeake Bay sediments, in equilibrium with vivianite, is a potential nutrient source for the overlying water. PMID:17831102

Bray, J T; Bricker, O P; Troup, B N

1973-06-29

333

Methyl mercury in lakes. Factors affecting its production and partitioning between water and sediment.  

National Technical Information Service (NTIS)

Radio-labelled inorganic Hg(sup 2+)((sup 203)Hg) was added to the water of microcosms containing lake sediment and water. Anaerobic incubation always resulted in concentrations of radio-labeled methyl mercury in the water at least one order of magnitude h...

O. Regnell

1995-01-01

334

LIQUID AND GAS CHROMATOGRAPHIC ANALYSIS OF DIETHYL PHTHALATE IN WATER AND SEDIMENT  

EPA Science Inventory

Diethyl phthalate was determined in water and sediment by high performance liquid chromatography (HPLC) and in water by gas-liquid chromatography with electron capture detection (GLC-ECD). Water samples were extracted with hexane, using a high-speed homogenizer-ultrasonic apparat...

335

A new collector for in situ pore water sampling in wetland sediment.  

PubMed

Currently available pore water samplers generally do not allow continuous monitoring of temporal variations in pore water composition. Therefore, a new type of pore water collector was designed and constructed. These collectors were constructed of polyvinyl chloride (PVC) materials, including PVC tubing with one end sealed and another end topped with a removable PVC screw-cap. A row of holes was drilled 10 cm from the sealed end of each collector. These new collectors were deployed in different layers of the sediment in a constructed wetland in Lake Taihu, China, to reveal variations in the nutrient composition of pore water with high spatial and temporal resolution. Specifically, the collectors were driven into the sediment, and the pore water flowed into the tubing via gravity. The pore water was then sampled from the PVC tubing using a portable vacuum pump, and then was taken to the lab within 20 min for analysis of the dissolved oxygen (DO) and nutrient concentration. The DO concentration of the pore water was below the detection limit for all samples, indicating that the pore water was probably not influenced by the air and that the water in the collector tube was representative of the pore water. These findings suggest that the collector is capable of measuring the temporal and spatial variations in the nutrient concentrations in pore water. Furthermore, the inexpensive material, ease of construction, minimal disturbance to the sediment and applicability for wetland sediments are advantages of the collector presented here compared with traditional pore water sampling techniques. PMID:22519110

Gao, Feng; Deng, Jiancai; Li, Qinqin; Hu, Liuming; Zhu, Jinge; Hang, Hongjuan; Hu, Weiping

336

In-Situ Parameter Estimation for Solar Domestic Hot Water Heating Systems Components  

NASA Astrophysics Data System (ADS)

Three different solar domestic hot water systems are being tested at the Colorado State University Solar Energy Applications Laboratory; an unpressurized drain-back system with a load side heat exchanger, an integral collector storage system, and an ultra low flow natural convection heat exchanger system. The systems are fully instrumented to yield data appropriate for in-depth analyses of performance. The level of detail allows the observation of the performance of the total system and the performance of the individual components. This dissertation evaluates the systems based on in-situ experimental data and compares the performances with simulated performances. The verification of the simulations aids in the rating procedure. The whole system performance measurements are also used to analyze the performance of individual components of a solar hot water system and to develop improved component models. The data are analyzed extensively and the parameters needed to characterize the systems fully are developed. Also resulting from this in-depth analysis are suggested design improvements either to the systems or the system components.

Smith, Toni Richele

337

Improving thermosyphon solar domestic hot water system model performance. Final report, March 1994--February 1995  

SciTech Connect

Data from an indoor solar simulator experimental performance test is used to develop a systematic calibration procedure for a computer model of a thermosyphoning, solar domestic hot water heating system with a tank-in-tank heat exchanger. Calibration is performed using an indoor test with a simulated solar collector to adjust heat transfer in the heat exchanger and heat transfer between adjacent layers of water in the storage tank. An outdoor test is used to calibrate the calculation of the friction drop in the closed collector loop. Additional indoor data with forced flow in the annulus of the heat exchanger leads to improved heat transfer correlations for the inside and outside regions of the tank-in-tank heat exchanger. The calibrated simulation model is compared to several additional outdoor tests both with and without auxiliary heating. Integrated draw energies are predicted with greater accuracy and draw temperature profiles match experimental results to a better degree. Auxiliary energy input predictions improve significantly. 63 figs., 29 tabs.

Swift, T.N.

1996-09-01

338

Chemical characterization of blue stains in domestic fixtures in contact with drinking water.  

PubMed

Bluish green staining in domestic fixtures was observed in three to 9-year-old houses in the city of Talca, located 256 km. south of Santiago, the capital of Chile. The houses contained copper pipes which were exposed to soft well water, with low pH and low buffer capacity. The aim of this paper is to establish the chemical composition of the stains and to determine the conditions by which they were formed. X-ray diffraction analysis of the stains revealed the presence of malachite, a copper compound that caused green coloring in kettles and water boilers. Dioptase, which is deep green in coloring, was identified in a bathtub tile. In one house, where blue stains were found in a toilet bowl, the presence of chrysocolla was suggested by means of X-ray fluorescence. In the field conditions studied it was concluded that the bluish green stains in bathroom home appliances were generated by the precipitation of copper compounds in places were leakages occur. PMID:17574543

Letelier, María V; Lagos, Gustavo E; Reyes, Arturo

2007-06-17

339

Effect of cuticle removal on the water vapour conductance of egg shells of several species of domestic bird  

Microsoft Academic Search

1. The effect of egg shell cuticle removal, using a 14.7 mM solution of sodium hypochlorite, on the water vapour conductance of egg shells was studied in 5 species of domestic bird.2. The water vapour conductance of fowl and Muscovy duck egg shells was not affected by the treatment.3. Cuticle removal increased the conductance of turkey and goose shells, particularly

D. C. Deeming

1987-01-01

340

Temperature tolerance and water balance in feral and domestic honey bees, Apis mellifera L  

Microsoft Academic Search

Feral and domestic honey bees were compared to determine relative levels of adaptation to the Arizona desert. Feral honey bees were more tolerant to high temperatures than domestic honey bees. Monthly critical thermal maxima (CTMs) of feral bees were significantly different from those of domestic bees (P < 0.001). The highest mean CTM for feral bees was 50.7 ± 1.0°C,

Anita H. Atmowidjojo; Diana E. Wheeler; Eric H. Erickson; Allen C. Cohen

1997-01-01

341

CONTRIBUTION OF AMMONIA, METALS AND NONPOLAR ORGANIC COMPOUNDS TO THE TOXICITY OF SEDIMENT INTERSTITIAL WATER FROM AN ILLINOIS RIVER TRIBUTARY  

EPA Science Inventory

Toxicity of Illinois River bulk sediment, sediment interstitial (pore) water and elutriates to the oligochaete Lumbriculus variegatus, fathead minnow (Pimephales promelas) and the amphipod Hyalella azteca was compared to determine the most representative aqueous fraction for toxi...

342

Survival of daphnia magna and hyalella azteca in cadmium-spiked water and sediment  

SciTech Connect

Freshwater sediments and water were spiked with cadmium (Cd) in the laboratory, and toxicity tests were conducted with the cladoceran Daphnia magna and the amphipod Hyalella azteca to determine if Cd in the sediment would cause increased toxicity. The 48-h LC50 values for Daphnia in tests without sediment were 36, 33, 24, and 40 micrograms/L total Cd. Calculated free-ion (Cd/sup 2 +/)LC50 values for the same tests were 28, 25, 18 and 31 micrograms/L. LC50 values (48-h) determined for total Cd(uncentrifuged water sample) in the sediment-containing beakers were 252, 69, and 122 micrograms/L for Daphnia. LC50 values for dissolved Cd(centrifuged 10,000 rpm) in the sediment-containing beakers were 61, 27, and 100 micrograms/L for Daphnia. Higher total Cd LC50 values indicate that Cd adsorbed to soluble organic material was not biologically available. No significant mortality of Daphnia or Hyalella occurred in the flow-through tests in which sediment contained the same levels of Cd as in the static tests. Mortality was similar in beakers with and without Cd-spiked sediment, indicating that Cd in the sediment and adsorbed to organic materials was not available to cause increased mortality.

Nebeker, A.V.; Onjukka, S.T.; Cairns, M.A.; Krawczyk, D.F.

1986-01-01

343

Screening toxicity evaluation of Wheeler Reservoir sediments using juvenile freshwater mussels (Anodonta imbecillis say) exposed to sediment interstitial water  

SciTech Connect

Reservoir sediments (porewater) near several wastewater outfalls at Decatur, Alabama, were screened for acute (9-day) toxicity to 8-day old freshwater mussels. Sampling locations corresponded to four of five sites previously surveyed by the Alabama Wildlife Federation and Alabama mussel divers. A site located on the opposite (north) overbank where mussels are abundant was chosen as the study control. Reference sediments from an outdoor channel at TVA's Aquatic Research Laboratory (ARL) with flow-through Wheeler Reservoir water and from a downstream (Kentucky) reservoir were included in the study for comparative purposes. Toxicity was observed at two of the Decatur sites, and in the ARL channel. Sediments from the other two Decatur sites, the north overbank (control), and Kentucky Reservoir were not toxic to the test animals. Toxicity at station Alpha and from the ARL channel was correlated with un-ionized ammonia present in porewater during the test. Toxicity at station Delta was above the level explained by the regression model examined for ammonia. The site at Decatur having the greatest toxicity and ammonia concentration (Alpha) was located in the Dry Branch Embayment. Elevated ammonia in sediment collected from ARL was attributed to natural events. 13 refs., 4 figs., 6 tabs.

Wade, D.C.

1990-12-01

344

Temporal variations of water and sediment fluxes in the Cointzio river basin, central Mexico  

NASA Astrophysics Data System (ADS)

The STREAMS program (Sediment TRansport and Erosion Across MountainS) was launched in 2006 to study suspended sediment dynamics in mountainous areas. Two watersheds were selected as part of the program: the Bléone river basin in the French Alps, and the Cointzio river basin (636 km2), located in the mountainous region of Michoacán, in central Mexico. The volcanic soils of the Cointzio catchment undergo important erosion processes, especially during flashflood events. Thus, a high-frequency monitoring of sediment transport is highly required. The poster presents the high-frequency database obtained from the 2008 hydrological season at the Santiago Undameo gauged station, located at the basin's outlet. Suspended Sediment Concentration (SSC) was estimated every 10 minutes by calibrating turbidity measurements with bottle sampling acquired on a double-daily basis. Water discharge time-series was approximated with continuous water-level measurements (5 minutes time-step), and a stage-discharge rating curve. Our investigation highlights the influence of sampling frequency on annual water and sediment fluxes estimate. A daily or even a weekly water-level measurement provides an unexpectedly reliable assessment of the seasonal water fluxes, with an under-estimation of about 5 % of the total flux. Concerning sediment fluxes, a high-frequency SSC survey appears to be necessary. Acquiring SSC data even twice a day leads to a significant (over 30 %) under-estimation of the seasonal sediment load. These distinct behaviors can be attributed to the fact that sediment transport almost exclusively occurs during brief night flood events, whereas exfiltration on the watershed always provides a base flow during the daily water-level measurements.

Duvert, C.; Gratiot, N.; Navratil, O.; Esteves, M.; Prat, C.; Nord, G.

2009-04-01

345

Measuring pyrethroids in sediment pore water using matrix-solid phase microextraction.  

PubMed

Pyrethroids are hydrophobic insecticides commonly used in both agricultural and urban environments. Their high toxicity to aquatic organisms, including benthic invertebrates, and detection in the sediment at many locations in California, U.S.A., have spawned interest in understanding their bioavailability in bed sediments. A recent study showed good correlation between uptake of 14C-permethrin in Chironomus tentans and solid-phase microextraction (SPME) fibers in sediments. The present study was directed at the development of an SPME technique applicable to trace levels of nonlabeled pyrethroids in sediment. Disposable polydimethylsiloxane fibers were used to detect freely dissolved pore-water concentrations of bifenthrin, fenpropathrin, cis-permethrin, trans-permethrin, cyfluthrin, cypermethrin, and esfenvalerate under agitated and static conditions. Partition equilibrium between fiber and sediment was reached in <5 d when the samples were agitated on a shaker at low speed, while much longer times (>23 d) were needed without agitation. Polydimethylsiloxane to water partition ratios (K(PDMS)) of the seven pyrethroids were measured separately and ranged from 2.83 x 10(5) to 1.89 x 10(6). When applied to field-contaminated sediments, agitated matrix-SPME was able to detect pore-water concentrations as low as 0.1 ng/L. The method developed in the present study may be coupled with bioassays to gain mechanistic understanding of factors affecting pyrethroid toxicities, and applied to field samples to better predict sediment toxicities from pyrethroid contamination. PMID:18712946

Hunter, Wesley; Yang, Yu; Reichenberg, Fredrik; Mayer, Philipp; Gan, Jianying

2009-01-01

346

[Water provision for domestic ducks kept indoors--a review on the basis of the literature and our own experiences].  

PubMed

The wild ancestors of the domestic pekin and muscovy ducks are anatomically, physiologically and behaviourally well adapted to living on and at the water. The domestic ducks kept for fattening purposes still show clear preferences for open water and make use of water for foraging and feeding, drinking, for general exploration, locomotion and preening, even without prior experience. For hygienic, labour, technical and economical reasons ducks are nowadays mostly kept in closed buildings without access to open water. This significantly restricts their freedom to show their natural behaviour. An obvious consequence of this restriction is a deteriorated plumage condition, especially with regard to cleanliness. According to the Council of Europe recommendations, water shall be provided in a way that allows the ducks to cover their head with water and shake it about their body without difficulty. To date, however, there is a lack of solutions satisfying behavioural, hygienic, health, labour and economical requirements to about equally tolerable degrees. The presently available types of different water provisions are presented and discussed on the basis of existing literature as well as experiences and first results from an ongoing research project. The provision of shallow bathing water with daily water exchange promises to be a practicable solution. However, longer term research on possible negative effects of the decreased hygienic quality of the water on duck health is necessary before final conclusions can be drawn. PMID:15195960

Knierim, U; Bulheller, M A; Kuhnt, K; Briese, A; Hartung, J

2004-03-01

347

Distributions of polycyclic aromatic hydrocarbons in surface waters, sediments and soils of Hangzhou City, China.  

PubMed

Ten polycyclic aromatic hydrocarbons (PAHs) were simultaneously measured in 17 surface water samples and 11 sediments of four water bodies, and 3 soils near the water-body bank in Hangzhou, China in December 2002. It was observed that the sum of PAHs concentrations ranged from 0.989 to 9.663 microg/L in surface waters, from 132.7 to 7343 ng/g dry weight in sediments, and from 59.71 to 615.8 ng/g dry weight in soils. The composition pattern of PAHs by ring size in water, sediment and soil were surveyed. Three-ring PAHs were dominated in surface waters and soils, meanwhile sediments were mostly dominated by four-ring PAHs. Furthermore, PAHs apparent distribution coefficients (K(d)) and solid f(oc)-normalized K(d) (e.g. K(oc)= K(d) / f(oc)) were calculated. The relationship between logK(oc) and logK(ow) of PAHs for field data on sediments and predicted values were compared. The sources of PAHs in different water bodies were evaluated by comparison of K (oc) values in sediments of the river downstream with that in soils. Hangzhou section of the Great Canal was heavily polluted by PAHs released from industrial wastewater in the past and now PAHs in sediment may serve as sources of PAHs in surface water. PAHs in Qiantang River were contributed from soil runoff. Municipal road runoff was mostly contributed to West Lake PAHs. PMID:15325182

Chen, Baoliang; Xuan, Xiaodong; Zhu, Lizhong; Wang, Jing; Gao, Yanzheng; Yang, Kun; Shen, Xueyou; Lou, Baofeng

2004-09-01

348

Mercury cycling in stream ecosystems. 2. Benthic methylmercury production and bed sediment - Pore water partitioning  

USGS Publications Warehouse

Mercury speciation, controls on methylmercury (MeHg) production, and bed sediment - pore water partitioning of total Hg (THg) and MeHg were examined in bed sediment from eight geochemically diverse streams where atmospheric deposition was the predominant Hg input. Across all streams, sediment THg concentrations were best described as a combined function of sediment percent fines (%fines; particles < 63 ??m) and organic content. MeHg concentrations were best described as a combined function of organic content and the activity of the Hg(II)-methylating microbial community and were comparable to MeHg concentrations in streams with Hg inputs from industrial and mining sources. Whole sediment tin-reducible inorganic reactive Hg (Hg(II)R) was used as a proxy measure for the Hg(II) pool available for microbial methylation. In conjunction with radiotracer-derived rate constants of 203Hg(II) methylation, Hg(II)R was used to calculate MeHg production potential rates and to explain the spatial variability in MeHg concentration. The %Hg(II)R (of THg) was low (2.1 ?? 5.7%) and was inversely related to both microbial sulfate reduction rates and sediment total reduced sulfur concentration. While sediment THg concentrations were higher in urban streams, %MeHg and %Hg(II)R were higher in nonurban streams. Sediment pore water distribution coefficients (log Kd's) for both THg and MeHg were inversely related to the log-transformed ratio of pore water dissolved organic carbon (DOC) to bed sediment %fines. The stream with the highest drainage basin wetland density also had the highest pore water DOC ?? 2009 American Chemical Society.

Marvin-Dipasquale, M.; Lutz, M. A.; Brigham, M. E.; Krabbenhoft, D. P.; Aiken, G. R.; Orem, W. H.; Hall, B. D.

2009-01-01

349

Detection and identification of human cell mutagens in sediments and surface waters of the Aberjona watershed  

SciTech Connect

It has been shown that sediments and surface waters in many parts of the Aberjona watershed in eastern Massachusetts contain high concentrations of toxic metals and organic pollutants. A study was conducted to assess the mutagenicity of sediment and surface water samples. Organic extracts of two of the sediments were found to be mutagenic. One of these sediments was from Wedge Pond, a pond which is used for recreational activities including fishing and swimming. To better understand the potential health risks posed by exposure to sediments in Wedge Pond, work was done to identify the principal human cell mutagens in the sediment extract. Having found that polycyclic aromatic hydrocarbons (PAH) were the principal class of organic mutagens in Wedge Pond sediments, efforts were made to determine the sources of these chemicals to the pond. By comparing the PAH assemblages in the top five sections of the sediment core with assemblages characteristic of non-combustion sources and low and high temperature combustion emission, it was found that the PAH assemblages in the sediments closely resemble low temperature combustion emissions. It was found that coal burning (presumably for residential heating) could account for PAH inputs from roughly the turn of the century to c.1960. Present-day inputs are believed to derive largely from wood combustion emissions. The dominant routes of delivery of PAH to the pond are likely to be direct atmospheric deposition of PAH-laden particulate matter and runoff of street dust. To determine whether mutagenic chemicals were also present in surface waters, a large-volume water sample extraction system was developed. Organic extracts of the filtered particles from one of the Aberjona River samples and the Wedge Pond sample were found to be mutagenic to human B-cells. The Wedge Pond particle extract was analyzed by gas chromatographic - mass spectrometric techniques and found to contain PAH.

Durant, J.L.

1993-01-01

350

Responses of wetland plants to effluents in water and sediment  

SciTech Connect

Responses of two wetland vascular plants, Echinochloa crusgalli and Sesbania macrocarpa, exposed to effluents from a coke plant, a pulp mill, a wastewater treatment plant, and the herbicide, hexazinone, were measured in three types of tests: seed germination and early growth, seedling survival and growth in hydroponic culture, and seedling survival and growth in sand and synthetic sediments with clay, silt, and sand, 3, 5, 7.5, or 10% organic contents. There was no effect of effluents or herbicide on germination and survival was affected only by the herbicide. When compared to controls, growth rates were reduced significantly in all tests except for E. crusgalli exposed to effluent from a wastewater treatment plant. There, the effluent stimulated growth in sediments. Increasing concentrations of organic matter in sediments had little effect on toxicity of effluents, but did cause reduced effects of hexazinone.

Walsh, G.E.; Weber, D.E.; Nguyen, M.T.; Esry, L.K.

1991-01-01

351

Water quality and heavy metal monitoring in water and sediment samples of the Küçükçekmece Lagoon, Turkey (2002-2003).  

PubMed

Physical and chemical parameters have been analyzed in water samples from a brackish water lagoon, Küçükçekmece, located on the western outskirts of Istanbul. Samples were collected every two months for a year from nine sampling stations. Of the parameters measured, temperature, pH, salinity, nitrate and phosphate showed changes when compared with the previously published data. The lagoon was found eutrophic as it was reported previously. Sulphate and COD levels were higher when compared with the standards established by the Turkish Water Pollution and Control Regulation. Additionally, concentrations of heavy metals (Cd, Co, Cr, Cu, Mn, Ni, Pb, Zn) in water and bottom sediments were measured and compared with the standards established by the Turkish Water Pollution and Control Regulation and with the previously published data. The results were analysed statistically with respect to location and any relationships between the concentration of the elements in corresponding water and sediment samples were examined. Principal Component Analysis of water samples allowed us to discriminate three areas affected mainly by heavy metal contamination, possibly due to industrial, commercial and/or urban activities. Generally, the concentrations of the heavy metals were higher at stations near the three estuaries, suggesting a direct influence of the three creeks on the pollution of the Küçükçekmece Lagoon. Although elevated levels of Cd were recorded in several water samples, it was not detected in sediment. On the other hand, a particularly high level of Cr pollution was recorded most of the water and sediment samples. PMID:18409013

Altun, Omer; Saçan, Melek Türker; Erdem, Ayten Kimiran

2008-04-12

352

Accumulation of Nitrogen in the Pore Water of Anoxic Lake Sediments  

NASA Astrophysics Data System (ADS)

The impact of soil runoff nitrogen on the Silver Lake of Iowa was assessed in this study. Currently, the lake cannot support its designated uses as a recreational water body. Extensive algal blooms characterize the lake in late summer, lowering the dissolved oxygen content in water (< 2.0 mg/L). The goal of this study was to map the buildup of nitrogen in the pore water of lake sediments and come up with recommendations for restoration strategies. Sediment cores were taken from 20 sites along 5 transects in the lake. In the top 5 cm of the sediments, the pore water nitrogen ranges between 1.8 and 733.1 micro-gm of nitrate per gm of sediments. The average concentration is 94 micro-g/gm. Vertically, nitrate concentrations were measured at 90 micro-g/gm at 0-10 cm, 95 micro-g/gm at 10-20 cm, and 19 micro-g/gm at 20-30 cm. The sharp decline in nitrate below the 20 cm depth in the sediment is attributed to biochemical reduction of nitrate through denitrification in relatively older, much anoxic sediments. The above results indicate that sediments in Silver Lake are heavily contaminated with N trapped in the pore water. The primary sources of N are the surrounding croplands and an active hog lot on the southeastern lakeshore. The average rate of sedimentation in the lake has been 1 cm/year in the last 32 years. Upon sedimentation, the pore water N is slowly released to the lake water, thereby dramatically limiting the lake's capability to process incoming nutrients. The mass distribution of N in the lake was estimated as 3.66 x 103 kg (65%) in bottom sediments, 172 kg (3%) in suspended particulates, and 1.83 x 103 kg (32%) in the dissolved phase. Some of the recommendations made through this study include dredging the top 25 cm of lake sediments, applying buffer strips along the lake's northern and eastern shorelines, and reducing the application of N and P-based fertilizers.

Iqbal, M. Z.; Fields, C. L.

2005-05-01

353

Sorption of alkylphenols on Ebro River sediments: comparing isotherms with field observations in river water and sediments.  

PubMed

This study reports sorption isotherms of the endocrine disruptors nonylphenol (NP) and octylphenol (OP) in three sediment samples from the Ebro River basin (NE Spain), with organic carbon fractions (f(OC)) ranging from 0.0035 to 0.082 g(OC)g(-1). All isotherms were fitted to the Freundlich model with slightly nonlinear exponents ranging from 0.80 to 0.94. The solubility of the compounds as well as the organic carbon (OC) content had the strongest influences on the sorption behavior of these compounds. Comparison of the laboratory-spiked samples with the native contamination of NP of 45 water and concurrent sediment samples resulted in reasonable matches between both data sets, even though the lowest concentrations in the field were not completely reached in laboratory tests. This good agreement indicates that sorption laboratory data can be extrapolated to environmental levels and therefore the distribution of nonylphenol between sediments and water can be predicted with a precision of one order of magnitude. Furthermore, laboratory experiments with simultaneous loading of NP and OP revealed negligible competition for sorption sites at low concentrations. PMID:18824283

Navarro, Alícia; Endo, Satoshi; Gocht, Tilman; Barth, Johannes A C; Lacorte, Sílvia; Barceló, Damià; Grathwohl, Peter

2008-09-27

354

Horizontal and vertical distribution of estrogenic activities in sediments and waters from Tokyo Bay, Japan.  

PubMed

Endocrine-disrupting chemicals with estrogenic activity (e.g., alkylphenols) have been detected in coastal Japan. We aimed to determine estrogenic activity in extracts of river water, seawater, sediments, and sediment cores from Tokyo Bay by in vitro gene expression assay. Fifty-one of 57 extracts had some estrogenic activity. E2 equivalents (ng E2 equivalents per gram dry weight or per liter above the limit of detection) in river water samples ranged from 0.70 to 4.01 ng/L; in seawater samples from 0.34 to 2.52 ng/L; and in surface sediments from 2.07 to 12.1 ng/g. The relationship between salinity and estrogenic activity in water samples suggested that fresh water is one source of environmental estrogens in Tokyo Bay. Fractionation of sediment extracts showed that the highest estrogenic activity was observed in the midpolar fraction. The observed activities were compared with activities mediated by known concentrations of nonylphenol, bisphenol-A, estrone, and 17beta-estradiol. In sediment collected near the sewage treatment plants, the estrogenic activity of the midpolar fraction could be explained about 34% by nonylphenol and estrone contained in this fraction. Core sediment measurements detected estrogenic activity from as far back as the 1960s. The regulations on the industrial wastewater in early 1970s would be one of the main reasons for the lower estrogenic activity in the upper section of the sediment core. The high estrogenic activities as measured in water and sediment samples from Tokyo might be restricted to certain coastal areas. PMID:15696346

Hashimoto, S; Horiuchi, A; Yoshimoto, T; Nakao, M; Omura, H; Kato, Y; Tanaka, H; Kannan, K; Giesy, J P

2005-01-04

355

Testing and analysis of load-side immersed heat exchangers for solar domestic hot water systems  

SciTech Connect

This report describes work to determine the performance of load-side heat exchangers for use in residential solar domestic hot water systems. We measured the performance of four heat exchangers: a smooth coil and a finned coil having heat transfer areas of 2.5 m/sup 2/ (26 ft/sup 2/) and those having areas of 1.7 m/sup 2/ (19 ft/sup 2/). A numerical model using the thermal network program MITAS was constructed, and results were compared to the experimental results. Research showed a smooth coil with only 70% of the surface area of a finned coil performed better than the finned coil. Also, load-side heat exchangers can maintain and enhance stratification in storage tanks, permitting the use of control strategies that take advantage of stratified storage tanks to increase system performance. The analytical model, which agreed reasonably well with the experimental results, was used to vary heat exchanger flow rate and area and initial tank temperature for both a smooth- and a finned-coil heat exchanger. Increasing the heat exchanger flow rate and area results in higher heat transfer rates but not necessarily optimal performance. Lower initial tank temperatures resulted in reduced tank stratification. The smooth heat exchanger outperformed the finned heat exchanger with the same outside surface area. 15 refs., 37 figs., 9 tabs.

Farrington, R.B.; Bingham, C.E.

1987-10-01

356

Low-Cost Solar Domestic Hot Water Systems for Mild Climates  

SciTech Connect

In FY99, Solar Heating and Lighting set the goal to reduce the life-cycle cost of saved-energy for solar domestic hot water (SDHW) systems in mild climates by 50%, primarily through use of polymer technology. Two industry teams (Davis Energy Group/SunEarth (DEG/SE) and FAFCO) have been developing un-pressurized integral-collector-storage (ICS) systems having load-side heat exchangers, and began field-testing in FY04. DEG/SE?s ICS has a rotomolded tank and thermoformed glazing. Based upon manufacturing issues, costs, and poor performance, the FAFCO team changed direction in late FY04 from an un-pressurized ICS to a direct thermosiphon design based upon use of pool collectors. Support for the teams is being provided for materials testing, modeling, and system testing. New ICS system models have been produced to model the new systems. A new ICS rating procedure for the ICS systems is undergoing testing and validation. Pipe freezing, freeze protection valves, and overheating have been tested and analyzed.

Burch, J.; Christensen, C.; Merrigan, T.; Hewett, R.; Jorgensen, G.

2005-01-01

357

Suspended sediment source areas and future climate impact on soil erosion and sediment yield in a New York City water supply watershed, USA  

NASA Astrophysics Data System (ADS)

High suspended sediment loads and the resulting turbidity can impact the use of surface waters for water supply and other designated uses. Changes in fluvial sediment loads influence material fluxes, aquatic geochemistry, water quality, channel morphology, and aquatic habitats. Therefore, quantifying spatial and temporal patterns in sediment loads is important both for understanding and predicting soil erosion and sediment transport processes as well as watershed-scale management of sediment and associated pollutants. A case study from the 891 km2 Cannonsville watershed, one of the major watersheds in the New York City water supply system is presented. The objective of this study was to apply Soil and Water Assessment Tool-Water Balance (SWAT-WB), a physically based semi-distributed model to identify suspended sediment generating source areas under current conditions and to simulate potential climate change impacts on soil erosion and suspended sediment yield in the study watershed for a set of future climate scenarios representative of the period 2081-2100. Future scenarios developed using nine global climate model (GCM) simulations indicate a sharp increase in the annual rates of soil erosion although a similar result in sediment yield at the watershed outlet was not evident. Future climate related changes in soil erosion and sediment yield appeared more significant in the winter due to a shift in the timing of snowmelt and also due to a decrease in the proportion of precipitation received as snow. Although an increase in future summer precipitation was predicted, soil erosion and sediment yield appeared to decrease owing to an increase in soil moisture deficit and a decrease in water yield due to increased evapotranspiration.

Mukundan, Rajith; Pradhanang, Soni M.; Schneiderman, Elliot M.; Pierson, Donald C.; Anandhi, Aavudai; Zion, Mark S.; Matonse, Adão H.; Lounsbury, David G.; Steenhuis, Tammo S.

2013-02-01

358

Phytoremediation of mercury- and methyl mercury-contaminated sediments by water hyacinth (Eichhornia crassipes).  

PubMed

Phytoremediation has the potential for implementation at mercury- (Hg) and methylHg (MeHg)-contaminated sites. Water hyacinths (Eichhornia crassipes) were investigated for their ability to assimilate Hg and MeHg into plant biomass, in both aquatic and sediment-associated forms, over a 68-day hydroponic study. The suitability of E. crassipes to assimilate both Hg and MeHg was evaluated under differing phosphate (PO4) concentrations, light intensities, and sediment:aqueous phase contamination ratios. Because aquatic rhizospheres have the ability to enhance MeHg formation, the level of MeHg in water, sediment, and water hyacinth was also measured. Hg and MeHg were found to concentrate preferentially in the roots of E. crassipes with little translocation to the shoots or leaves of the plant, a result consistent with studies from similar macrophytes. Sediments were found to be the major sink for Hg as they were able to sequester Hg, making it non-bioavailable for water hyacinth uptake. An optimum PO4 concentration was observed for Hg and MeHg uptake. Increasing light intensity served to enhance the translocation of both Hg and MeHg from roots to shoots. Assimilation of Hg and MeHg into the biomass of water hyacinths represents a potential means for sustainable remediation of contaminated waters and sediments under the appropriate conditions. PMID:22567701

Chattopadhyay, Sandip; Fimmen, Ryan L; Yates, Brian J; Lal, Vivek; Randall, Paul

2012-02-01

359

Biogeochemistry of (210)Pb and (210)Po in fresh waters and sediments. Doctoral thesis  

SciTech Connect

The geochemical cycling of (210)Pb in a Massachusetts lake was studied. A mass balance for the epilimnion showed that (210)Pb inputs by precipitation were matched by outputs on settling particles, so direct uptake by bottom sediments was inconsequential. Below the epilimnion, vertical mixing was very low because of a steep temperature/density gradient, and this limited vertical transport. Anoxic conditions caused remobilization of iron and (210)Pb, which reprecipitated at the oxycline and returned to the bottom via settling. Below the zone of precipitation, (210)Pb and iron distributions resulted from constant release from anoxic sediments and dilution in the water column. Sediment (210)Pb distributions were caused by sedimentation and Fickian transport. The Fickian component was equal to the pore water diffusive flux. In pore waters, (210)Pb and (210)Po were 100 times greater that in overlying water and had steep concentration gradients, unlike Fe, Mn, S(-II), and alkalinity. (210)Pb partition coefficients decreased from 15000 to 1500 with depth controlled by sorption on iron oxides. Remobilization to the water column comes from a thin layer of iron-rich floc near the sediment/water interface. Deeper in the cores, diffusive transport can cause redistribution of (210)Pb to an extent that can affect (210)Pb dating.

Benoit, G.

1988-06-01

360

Enzyme activities in the water column and in shallow permeable sediments from the northeastern Gulf of Mexico  

NASA Astrophysics Data System (ADS)

The activities of extracellular enzymes that initiate the microbial remineralization of high molecular weight organic matter were investigated in the water column and sandy surface sediments at two sites in the northeastern Gulf of Mexico. Six fluorescently labeled polysaccharides were hydrolyzed rapidly in the water column as well as in permeable sediments. This result contrasts with previous studies carried out in environments dominated by fine-grained muds, in which the spectrum of enzymes active in the water column is quite limited compared to that of the underlying sediments. Extracts of Spirulina, Isochrysis, and Thalassiosira were also used to measure hydrolysis rates in water from one of the sites. Rates of hydrolysis of the three plankton extracts were comparable to those of the purified polysaccharides. The broad spectrum and rapid rates of hydrolysis observed in the water column at both sites in the northeastern Gulf of Mexico may be due to the permeable nature of the sediments. Fluid flux through the sediments is sufficiently high that the entire 1.5 m deep water column could filter though the sediments on timescales of a few days to two weeks. Movement of water through sediments may also transport dissolved enzymes from the sediment into the water column, enhancing the spectrum as well as the rate of water column enzymatic activities. Such interaction between the sediments and water column would permit water column microbial communities to access high molecular weight substrates that might otherwise remain unavailable as substrates.

Arnosti, C.; Ziervogel, K.; Ocampo, L.; Ghobrial, S.

2009-09-01

361

Sedimentation on the cold-water coral Lophelia pertusa: cleaning efficiency from natural sediments and drill cuttings.  

PubMed

Anthropogenic threats to cold-water coral reefs are trawling and hydrocarbon drilling, with both activities causing increased levels of suspended particles. The efficiency of Lophelia pertusa in rejecting local sediments and drill cuttings from the coral surface was evaluated and found not to differ between sediment types. Further results showed that the coral efficiently removed deposited material even after repeated exposures, indicating an efficient cleaning mechanism. In an experiment focusing on burial, fine-fraction drill cuttings were deposited on corals over time. Drill cutting covered coral area increased with repeated depositions, with accumulation mainly occurring on and adjacent to regions of the coral skeleton lacking tissue cover. Tissue was smothered and polyp mortality occurred where polyps became wholly covered by material. Burial of coral by drill cuttings to the current threshold level used in environmental risk assessment models by the offshore industry (6.3mm) may result in damage to L. pertusa colonies. PMID:21529851

Larsson, Ann I; Purser, Autun

2011-05-06

362

ABIOTIC TRANSFORMATIONS OF PESTICIDES IN NATURAL WATERS AND SEDIMENTS  

EPA Science Inventory

Selected organic compounds can undergo abiotic reduction in anaerobic sediment systems. he factors that govern these reactions are not well defined, but the chemistry and the biology are strongly coupled. o ideal methodology is now available to quantitatively separate the contrib...

363

Field Evaluation Of Arsenic Transport Across The Ground Water/Surface Water Interface: Speciation In Sediment Material  

EPA Science Inventory

The solubility and mobility of arsenic in ground water are influenced by a variety of processes in the northeastern US subjective to geogenic and anthropogenic sources. This presentation will discuss the speciation of arsenic in sediment profiles resulting from ground water disc...

364

Impact of Persistent Degassing of Kilauea Volcano on Domestic Water Supplies  

NASA Astrophysics Data System (ADS)

In March, 2008, a small explosive eruption in the summit crater of Kilauea Volcano marked the initiation of a new, persistently degassing vent at Kilauea. Emission rates of sulfur dioxide initially exceeded 1000 tons per day but declined to a longer term rate of ~800 tons per day. Because of its location farther inland, the plume from this vent generated more severe and more frequent adverse air quality impacts on the surrounding and downwind communities than has the longer lived degassing vents at Pu'u O'o. Because many residents on Hawaii Island derive their domestic water supply from roof catchment systems, deposition of aerosols produced in the volcanic plume could pose a significant health threat to the community. In order to quantify that risk, a program of screening of water catchment systems was undertaken in three communities: Lower Puna, upwind of the vent; Volcano Village, immediately adjacent to the Kilauea summit; and Hawaiian Ocean View Estates, located ~65 km downwind from the vent. An aggregate of 439 samples were collected and analyzed for pH, and fluoride, chloride and sulfate ion concentrations; the median values and extrema are shown in Table I below. The pH values for the catchments proved not to be a good indicator of plume influence: the Volcano and Ocean View communities showed a bimodal distribution of values reflecting residents managing their water systems (median pH = 6.2 and 7.2 respectively) and those that didn't (median pH = 4.5 and 4.3 respectively); however, the lower extremes for pH gave values of 2.9 and 3.3 respectively. Chloride values were also variable due to the use of sodium hypochlorite to treat for biological contaminants. The median values for fluoride and sulfate show a progressive increase from the Puna catchments to Volcano and Ocean View. We believe that these values are consistent with the relative exposure of the communities to the volcanic plume: although the Volcano community is closer to the source, wind conditions conducive to exposure are infrequent whereas the more distant Ocean View community is exposed to a more dilute plume but at a much higher frequency. Even though the median values are within accepted limits for drinking water, the extreme values observed are cause for concern: the pH values are well below those recommended for drinking water and the fluoride values are approaching WHO recommended drinking water levels. With even modest increases in plume output or exposure times, some of the community catchment systems can accumulate sufficient acid or fluoride ion concentrations to pose a significant health threat if drinking water is drawn from those catchments. Continued monitoring of catchment water quality is recommended.Table I. Catchment Water Supply Analytical Results Concentrations in parts per million

Thomas, D. M.; Macomber, T.

2010-12-01

365

Evaluation of hexavalent chromium in sediment pore water of the Hackensack River, New Jersey, USA.  

PubMed

Pore water was collected from in situ passive samplers in Hackensack River sediments adjacent to a chromite ore processing residue site in Kearny, New Jersey. Although the sediments at this site contained more than 3,000 mg/kg of total chromium (Cr) and shallow groundwater adjacent to the shore contained more than 1,000 microg/L of hexavalent Cr [Cr(VI)], concentrations of dissolved total Cr and Cr(VI) in pore water (PW) samples were less than ambient water quality criteria for Cr(VI) (50 microg/L). Concentrations of dissolved total Cr in pore water ranged from <2.0 to 5.3 microg/L, while Cr(VI) was not detected (<10 microg/L). These findings are consistent with previous studies, which demonstrated limited bioavailability and toxicity of Cr in sediment at this site and others with similar conditions. PMID:20821486

Driscoll, Susan Kane; McArdle, Margaret E; Plumlee, Megan H; Proctor, Deborah

2010-03-01

366

A new device for collection of interstitial water from wetland sediments  

USGS Publications Warehouse

A sampler for collection of interstitial water from wetland sediments is described. It differs from other sampling devices because it does not have to be filled with solution to facilitate diffusion, it does not have to be removed from the wetland to collect samples, and it can be used to draw repeated samples over time from identical locations. The device facilitates 'in situ' measurement of a wide range of abiotic parameters such as electrical conductivity, redox potential, and pH in wetland sediments. The device has application in ecological investigations of sediment-borne wildlife diseases, studies of benthic invertebrates, measurement of nutrient exchange, and other aspects of wetland ecology.

Euliss, N. H., Jr.; Barnes, R. K.

1992-01-01

367

Residential Ground Source Heat Pumps with Integrated Domestic Hot Water Generation: Performance Results from Long-Term Monitoring  

SciTech Connect

Ground source heat pumps (GSHPs) show promise for reducing house energy consumption, and a desuperheater can potentially further reduce energy consumption where the heat pump from the space conditioning system creates hot water. Two unoccupied houses were instrumented to document the installed operational space conditioning and water heating efficiency of their GSHP systems. This paper discusses instrumentation methods and field operation characteristics of the GSHPs, compares manufacturers' values of the coefficients of performance calculated from field measured data for the two GSHPs, and compares the measured efficiency of the desuperheater system to other domestic hot water systems.

Stecher, D.; Allison, K.

2012-11-01

368

Concentration of arsenic in water, sediments and fish species from naturally contaminated rivers.  

PubMed

Arsenic (As) may occur in surface freshwater ecosystems as a consequence of both natural contamination and anthropogenic activities. In this paper, As concentrations in muscle samples of 10 fish species, sediments and surface water from three naturally contaminated rivers in a central region of Argentina are reported. The study area is one of the largest regions in the world with high As concentrations in groundwater. However, information of As in freshwater ecosystems and associated biota is scarce. An extensive spatial variability of As concentrations in water and sediments of sampled ecosystems was observed. Geochemical indices indicated that sediments ranged from mostly unpolluted to strongly polluted. The concentration of As in sediments averaged 6.58 ?g/g ranging from 0.23 to 59.53 ?g/g. Arsenic in sediments barely followed (r = 0.361; p = 0.118) the level of contamination of water. All rivers showed high concentrations of As in surface waters, ranging from 55 to 195 ?g/L. The average concentration of As in fish was 1.76 ?g/g. The level of contamination with As differed significantly between species. Moreover, the level of bioaccumulation of As in fish species related to the concentration of As in water and sediments also differed between species. Whilst some fish species seemed to be able to regulate the uptake of this metalloid, the concentration of As in the large catfish Rhamdia quelen mostly followed the concentration of As in abiotic compartments. The erratic pattern of As concentrations in fish and sediments regardless of the invariable high levels in surface waters suggests the existence of complex biogeochemical processes behind the distribution patterns of As in these naturally contaminated ecosystems. PMID:23179469

Rosso, Juan José; Schenone, Nahuel F; Pérez Carrera, Alejo; Fernández Cirelli, Alicia

2012-11-23

369

Domestic Violence  

MedlinePLUS

Domestic Violence Domestic violence is an escalating pattern of violence or intimidation by an intimate partner, which is used to gain power and control. Several categories of domestic violence against the elderly have been identified: "Domestic violence ...

370

Speciation of metals in bed sediments and water of Qaraaoun Reservoir, Lebanon  

Microsoft Academic Search

Determination of only total element in sediments does not give an accurate estimate of the likely environmental impacts. Speciation\\u000a study of metals in sediment provides information on the potential availability of metals (toxic) to biota under various environmental\\u000a conditions. In water, the toxic metal specie is the free hydrated metal ion. The toxicity of metals depends especially on\\u000a their chemical

Samira Ibrahim Korfali; Mey S. Jurdi

2011-01-01

371

Removal of Zinc from Tidal Water by Sediments of a Mangrove Ecosystem: A Radiotracer Study  

Microsoft Academic Search

The removal of 65Zn from tidal water by underlaying sediment cores collected in a mangrove forest and a tidal creek that drains this forest\\u000a in Sepetiba Bay (SE Brazil) was investigated. After 30-h experiments in laboratory microcosms, the 65Zn half-removal times from tidal creek and mangrove forest sediments were 8.7?±?1.8 and 9.2?±?0.9 h respectively. Depth penetration\\u000a of 65Zn was mainly restricted

E. C. Machado; W. Machado; L. F. Bellido; S. R. Patchineelam; A. V. B. Bellido

2008-01-01

372

Rare earth elements in the pore waters of reducing nearshore sediments  

Microsoft Academic Search

The REE are mobile during early diagenesis in reducing nearshore sediments of Buzzards Bay leading to greatly enhanced concentrations in pore waters, e.g. 815 pmol kg-1 Nd and 1910 pmol kg-1 Ce within 30 cm of the sediment-seawater interface, about 10-50 times local seawater values. Two principal diagenetic reactions have been identified. Preferential Ce enrichment (positive Ce anomalies) and preferential

H. Elderfield; E. R. Sholkovitz

1987-01-01

373

Natural and artificial radionuclides in the Suez Canal bottom sediments and stream water  

Microsoft Academic Search

Concentration of natural and artificial radionuclides in Suez Canal bottom sediments and stream water have been measured using gamma spectrometers based on a hyper-pure Ge detector. The activity concentrations of 238U series, 232Th series and 40K did not exceed 16.0, 15.5 and 500.0 Bq kg-1 dry weight for sediments. The activity concentration of 238U series and 40K did not exceed

M. S. El-Tahawy; M. A. Farouk; N. M. Ibrahiem; S. A. M. El-Mongey

1994-01-01

374

Methyl t-Butyl Ether Mineralization in Surface-Water Sediment Microcosms under Denitrifying Conditions  

USGS Publications Warehouse

Mineralization of [U-14C] methyl t-butyl ether (MTBE) to 14CO2 without accumulation of t-butyl alcohol (TBA) was observed in surface-water sediment microcosms under denitrifying conditions. Methanogenic activity and limited transformation of MTBE to TBA were observed in the absence of denitrification. Results indicate that bed sediment microorganisms can effectively degrade MTBE to nontoxic products under denitrifying conditions.

Bradley, P. M.; Chapelle, F. H.; Landmeyer, J. E.

2001-01-01

375

Sediment-to-water blue-green algal recruitment in response to alum and environmental factors  

Microsoft Academic Search

The sediment-to-water recruitment of blue-green algae was investigated in a shallow lake following treatment with aluminum sulfate and sodium aluminate to control sediment phosphorus (P) release. A comparison of results from two summers each before and after treatment indicates that the treatment did not universally impact the recruitment of either sporulating or non-sporulating forms of blue-green algae. Blooms of Anabaena,

Steven S. Perakis; Eugene B. Welch; Jean M. Jacoby

1996-01-01

376

On a Sediment Transport Model in Shallow Water Equations with Gravity Effects  

Microsoft Academic Search

\\u000a Sediment transport by a fluid over a sediment layer can be modeled by a coupled system with a hydrodynamical component, described\\u000a by a shallow water system, and a morphodynamical component, given by a solid transport flux. Meyer-Peter and Müller developed\\u000a one of the most known formulae for solid transport discharge, but it has the inconvenient of not including pressure forces.

T. Morales de Morales Luna; M. J. Castro Díaz; C. Parés Madroñal

377

Arctic sediments (Svalbard): pore water and solid phase distributions of C, N, P and Si  

Microsoft Academic Search

Pore water and solid phase distributions of C, N, P and Si in sediments of the Arctic Ocean (Svalbard area) have been investigated.\\u000a Concentrations of organic carbon (Corg) in the solid phase of the sediment varied from 1.3 to 2.8% (mean 1.9%), with highest concentrations found at shallow stations\\u000a south\\/southwest of Svalbard. Relatively low concentrations were obtained at the deeper

S. Hulth; P. O. J. Hall; A. Landén; T. H. Blackburn

1996-01-01

378

Residues of Organochlorines in Sediments and Tilapia Collected from Inland Water Systems of Hong Kong  

Microsoft Academic Search

.   The levels and patterns of organochlorines including DDTs, HCHs, and PCBs were investigated in sediments and tilapia (Tilapia mossambica) collected from inland water systems [Tai Wai (S1), Fo Tan (S2), Siu Lek Yuen (S3), Tai Po (S4), and Tai Wo (S5)] in the\\u000a New Territories of Hong Kong. Sediment and tilapia samples were also collected from two fish ponds

H. Y. Zhou; R. Y. H. Cheung; M. H. Wong

1999-01-01

379

Infaunal burrow ventilation and pore-water transport in muddy sediments  

Microsoft Academic Search

The ventilation of burrows by tube-dwelling benthos is understood to be important in determining rates of exchange of solutes between the sediment and overlying water. However, few models have attempted to link the burrow ventilation behavior of tube-dwelling organisms with their geochemical consequences. The classic cylinder model of bioirrigation in muddy sediments (Aller, R.C., 1980. Quantifying solute distributions in the

D. H. Shull; J. M. Benoit; C. Wojcik; J. R. Senning

2009-01-01

380

Horizontal and Vertical Distribution of Estrogenic Activities in Sediments and Waters from Tokyo Bay, Japan  

Microsoft Academic Search

Endocrine-disrupting chemicals with estrogenic activity (e.g., alkylphenols) have been detected in coastal Japan. We aimed to determine estrogenic activity in extracts of river water, seawater, sediments, and sediment cores from Tokyo Bay by in vitro gene expression assay. Fifty-one of 57 extracts had some estrogenic activity. E2 equivalents (ng E2 equivalents per gram dry weight or per liter above the

S. Hashimoto; A. Horiuchi; T. Yoshimoto; M. Nakao; H. Omura; Y. Kato; H. Tanaka; K. Kannan; J. P. Giesy

2005-01-01

381

COSOLVENT EFFECTS ON PHENANTHRENE SORPTION-DESORPTION ON A FRESH-WATER SEDIMENT  

EPA Science Inventory

This study evaluated the effects of the water-miscible cosolvent methanol on the sorption-desorption of phenanthrene by the natural organic matter (NOM) of a fresh-water sediment. A biphasic pattern was observed in the relationship between the log of the carbon-normalized sorpti...

382

Juvenile chemical sediments and the long term persistence of water at the surface of Mars  

Microsoft Academic Search

Chemical sediments and the aqueous alteration products of volcanic rocks clearly indicate the presence of water, at least episodically, at the Martian surface. Compared to similar materials formed on the early Earth, however, Martian deposits are juvenile, or diagenetically under-developed. Here we examine the role of water in facilitating various diagenetic reactions and evaluate the predicted effects of time and

Nicholas J. Tosca; Andrew H. Knoll

2009-01-01

383

Modeling water and sediment contamination of Lake Pontchartrain following pump-out of Hurricane Katrina floodwater  

Microsoft Academic Search

Levee failure and overtopping as a result of Hurricane Katrina caused major flooding of New Orleans, Louisiana. Floodwaters, which were contaminated with heavy metals, organic chemicals, and fecal coliform bacteria (FCB), were pumped into neighboring Lake Pontchartrain during dewatering. The impact of levee failure on water and benthic sediment concentrations in the lake was investigated by applying a numerical water

Mark S. Dortch; Mansour Zakikhani; Sung-Chan Kim; Jeffery A. Steevens

2008-01-01

384

Development and Demonstration of a Bidirectional Advective Flux Meter for Sediment-Water Interface.  

National Technical Information Service (NTIS)

A bidirectional advective flux meter for measuring water transport across the sediment-water interface has been successfully developed and field tested. The flow sensor employs a heat-pulse technique combine with a flow collection funnel for the flow meas...

B. K. Lien

2006-01-01

385

Indicator bacteria in water and stream sediments near the snowy range in Southern Wyoming  

Microsoft Academic Search

Water samples were taken at eight pools in streams in the Nash Fork watershed after snowmelt in the summer of I980. The watershed is below the Snowy Range escarpment, and principal land uses include skiing and other winter sports, sheep and cattle grazing, camping and fishing, and summer homes. Water samples taken before and after disturbing streambottom sediment were analyzed

Howard L. Gary; John C. Adams

1985-01-01

386

Polychlorinated organic compounds (PCOCs) in waters, suspended solids and sediments of the Yangtse River  

Microsoft Academic Search

The contamination levels of polychlorinated organic compounds (PCOCs) in waters, suspended solids and sediments of the Yangtse River (Nanjing part) were analyzed in this paper. Their concentrations determined by GC\\/MS were very low in comparison with those in European River. The average concentration of total HCH (?-HCH, ?-HCH, ?-HCH) was much higher than that of other PCOCs in all waters,

X Jiang; D Martens; K.-W Schramm; A Kettrup; S. F Xu; L. S Wang

2000-01-01

387

Protoplast Water Content of Bacterial Spores Determined by Buoyant Density Sedimentation.  

National Technical Information Service (NTIS)

Protoplast wet densities (1.315 to 1.400 g/ml), determined by buoyant density sedimentation in Metrizamide gradients, were correlated inversely with the protoplast water contents (26.4 to 55.0 of water/100 g of wet protoplast) of nine diverse types of pur...

J. A. Lindsay T. C. Beaman P. Gerhardt

1985-01-01

388

Heavy Metal Concentrations in Water, Sediment, Fish and Some Benthic Organisms from Tigris River, Turkey  

Microsoft Academic Search

In this study concentrations of heavy metals, such as Cd, Co, Cu, Fe, Mn, Ni, Pb and Zn were determined in water, sediment,\\u000a muscle, liver and gill of fish (Silurus triostegus, Mastacembelus simack, Mystus halepensis, Orthrias euphraticus) the muscle and liver of crab (Potamon fluviatilis), the internal organs of fresh water snail (Physa acuta), and mussel (Unio elongatulus), and in

Hülya Karadede-Akin; Erhan Ünlü

2007-01-01

389

Acidification of Harbor Sediment and Removal of Heavy Metals Induced by Water Splitting in Electrodialytic Remediation  

Microsoft Academic Search

Harbor sediments are often contaminated with heavy metals, which can be removed by electrodialytic remediation. Water splitting at the anion exchange membrane in contact with the contaminated material in electrodialytic remediation is highly important for the removal of heavy metals. Here it was investigated how acidification caused by water splitting at the anion exchange membrane during electrodialytic remediation of contaminated

Gunvor M. Nystroem; Lisbeth M. Ottosen; Arne Villumsen

2005-01-01

390

Initial results and progress of the Mississippi delta sediment pore water pressure experiment  

Microsoft Academic Search

This report describes the instrumentation, initial results, and progress of an experiment designed to measure and monitor submarine sediment pore water and hydrostatic pressures in a selected area of the Mississippi Delta. The experiment also is intended to monitor significant pressure perturbations during active storm periods. Initial analysis of the data revealed excess pore water pressures in the silty clay

Richard H. Bennett; William R. Bryant; Wayne A. Dunlap; George H. Keller

1976-01-01

391

Land conversion to bioenergy production: water budget and sediment output in a semiarid grassland  

Technology Transfer Automated Retrieval System (TEKTRAN)

Switchgrass based bioenergy production has been considered a feasible alternative of land use for the mixed-grass prairie and marginal croplands in the High Plains. However, little is known of the effect of this land use change on the water cycle and associated sediment output in this water controll...

392

DEVELOPMENT AND DEMONSTRATION OF A BIDIRECTIONAL ADVECTIVE FLUX METER FOR SEDIMENT-WATER INTERFACE  

EPA Science Inventory

A bidirectional advective flux meter for measuring water transport across the sediment-water interface has been successfully developed and field tested. The flow sensor employs a heat-pulse technique combined with a flow collection funnel for the flow measurement. Because the dir...

393

TOXICITY OF CADMIUM IN WATER AND SEDIMENT SLURRIES TO 'DAPHNIA MAGNA'  

EPA Science Inventory

Daphnia magna Straus were exposed to cadmium for 48 h in water and in equilibrated water sediment slurries using breakers and recirculating test chambers. Differences in toxicity based on dissolved and free cadmium (Cd(2+)) between the two levels of tested total solids 100 and 10...

394

Evidence for excess pore-water pressure generated in subglacial sediment: Implications for clast ploughing  

Microsoft Academic Search

Pore water pressure in front of an object pulled through subglacial sediment and water pressure at the base of a borehole were simultaneously recorded at Unteraargletscher, Switzerland, to investigate the generation of excess pore pressures downglacier from ploughing clasts. Analysis of the strongly correlated pressure records revealed that the amplitude of the pore-pressure fluctuations was larger than that of the

M. Rousselot; U. H. Fischer

2005-01-01

395

Speciation of selenium and arsenic in natural waters and sediments. Volume 2. Arsenic speciation. Final report  

SciTech Connect

The disposal of coal combustion wastes is an environmental concern to the electrical power utilities because high concentrations of potentially toxic water-soluble trace elements, such as arsenic (As), may be released. During the last two years research was conducted to (1) develop a methodology for As speciation in waters and sediments, (2) predict the equilibrium speciation of As in natural waters using geochemical modeling techniques, and (3) determine the chemical speciation of As in fresh water and sediment of a reservoir which receives coal fly ash. The analytical methodologies have been developed for collection, storage and analysis of freshwater and sediment without significantly altering the speciation of As. Arsenic speciation of water and sediment is simply and reproducibly achieved using hydride generation in conjunction with atomic absorption detection. Very rapid freezing by immersion in liquid nitrogen followed by storage at -80/sup 0/C is necessary to prevent oxidation of As (III) to As (V) during storage of water samples. Arsenic species are selectively extracted from sediment. At pH 2.3, As (III) is extracted and at pH 11.9 As (V) MMA and DMA are extracted. Field samples were collected from Hyco Reservoir in February and July 1984. The reservoir is apparently contaminated by As discharged from a coal fly ash pond. The majority of As is in the (V) valence state in the water column and ash pond. However, in the interstitial water squeezed from the reservoir sediments, As is equally divided between (V) and (III). 9 figs., 25 tabs.

Crecelius, E.A.; Bloom, N.S.; Cowan, C.E.; Jenne, E.A.

1986-06-01

396

An algorithm for the retrieval of suspended sediment in coastal waters of China from AVHRR data  

NASA Astrophysics Data System (ADS)

An algorithm using an analytical model based on the difference of the NOAA/AVHRR (Advanced Very High Resolution Radiometer) Channel 1 (580-680 nm) and Channel 2 (720-1100 nm) reflectance data is developed for the retrieval of suspended sediment in coastal and shelf waters. The model assumes that the suspended sediment concentration, S, is a function of the difference of the water leaving reflectance of Channels 1 and 2, Rd. The formula is governed by the optical parameters of water and suspended sediment, including volume scattering and absorption coefficients of the two channels. The analytical model yielded a best fit curve when the water leaving reflectance of the two channels were plotted against each other for Case 2 water, where the suspended sediment concentration ranged from 5 to over 100 g m -3. A standard curve of S against Rd was obtained. Using Tassan (1994)'s recommendations for the contribution of water and suspended sediment to the in-water absorption and backscattering coefficients in his three-component color model, the suspended sediment concentration corresponding to the maximum point of Rd was about 60 g m -3, and was independent of the atmospheric optical properties. Thus, this process provides a convenient tool to remove the atmospheric fluctuations of atmospheric transmittance by reconciling the maximum point of the image with the standard curve. The algorithm was tested using data from seven transects in the China Sea, and the retrieved results for the Zhujiang (Pearl River) Estuary were compared with the sea-truth data with good agreement. This suggests that the algorithm can be used as a seasonal regional model for water masses along the China coast.

Li, Yan; Huang, Wei; Fang, Ming

1998-04-01

397

Short-time response in root morphology of Vallisneria natans to sediment type and water-column nutrient  

Microsoft Academic Search

Rooted submerged macrophytes can absorb significant amounts of nutrients from both sediment and water. We investigated root morphology of Vallisneria natans in mesocosm plastic bins, in response to three types of sediment (sandy loam, clay, and a 50:50 (v\\/v) mixture of the two sediments) and two levels of water-column nutrient (well water and nutrient medium). Compared to the plants grown

Yonghong Xie; Shuqing An; Xin Yao; Keyan Xiao; Cheng Zhang

2005-01-01

398

Development of Layered Sediment Structure and its Effects on Pore Water Transport and Hyporheic Exchange  

SciTech Connect

Hyporheic exchange is known to provide an important control on nutrient and contaminant fluxes across the stream-subsurface interface. Similar processes also mediate interfacial transport in other permeable sediments. Recent research has focused on understanding the mechanics of these exchange processes and improving estimation of exchange rates in natural systems. While the structure of sediment beds obviously influences pore water flow rates and patterns, little is known about the interplay of typical sedimentary structures, hyporheic exchange, and other transport processes in fluvial/alluvial sediments. Here we discuss several processes that contribute to local-scale sediment heterogeneity and present results that illustrate the interaction of overlying flow conditions, the development of sediment structure, pore water transport, and stream-subsurface exchange. Layered structures are shown to develop at several scales within sediment beds. Surface sampling is used to analyze the development of an armor layer in a sand-and-gravel bed, while innovative synchrotron-based X-ray microtomography is used to observe patterns of grain sorting within sand bedforms. We show that layered bed structures involving coarsening of the bed surface increase interfacial solute flux but produce an effective anisotropy that favors horizontal pore water transport while limiting vertical penetration.

Packman, Aaron I.; Marion, Andrea; Zaramella, Mattia; Chen, Cheng; Gaillard, Jean-François; Keane, Denis T. (Padua); (NWU)

2008-04-15

399

Light dependent sediment-water exchange of dissolved reactive phosphorus and silicon in a producing microflora mat  

Microsoft Academic Search

Light dependent sediment-water exchange rates of dissolved reactive silicon (DRSi) and phosphorus (DRP) were studied on field station Archipel (3 m water depth) in Lake Grevelingen (SW Netherlands). Bell jars, either light or darkened, were fixed permanently over a productive microflora mat of mainly Navicula spp.; sediment-water exchange was monitored over an 11 days period. Gross primary production values in

P. Kelderman; H. J. Lindebooml; J. Klein

1988-01-01

400

Suspended-sediment and fresh-water discharges in the Ob and Yenisey rivers, 1960-1988  

Microsoft Academic Search

Of the world's great rivers, the Ob and Yenisey rank among the largest suppliers of fresh water and among the smallest suppliers of suspended sediment to the coastal ocean. Sediment in the middle reaches of the rivers is mobilized from bordering terraces and exchanged between channels and flood plains. Sediment in the lower reaches of these great rivers is deposited

R. H. Meade; N. N. Bobrovitskaya; V. I. Babkin

2000-01-01

401

Enhancing the start-up of a UASB reactor treating domestic wastewater by adding a water extract of Moringa oleifera seeds  

Microsoft Academic Search

Water extract of Moringa oleifera seeds (WEMOS) was used to enhance the start-up of a self-inoculated upflow anaerobic sludge blanket (UASB) reactor treating raw domestic wastewater. Two reactors labelled control (RC) and WEMOS addition (RM) were started without special inoculum. Both reactors were fed continuously for 22 weeks with domestic wastewater containing an average total chemical oxygen demand (COD) of

Y. Kalogo; A. M'Bassiguié Séka; W. Verstraete

2001-01-01

402

Factors controlling the silicon isotope distribution in waters and surface sediments of the Peruvian coastal upwelling  

NASA Astrophysics Data System (ADS)

We present the first systematic study of the silicon isotope composition in the water column (?30Si) and in diatoms (?30Sidiatom) from the underlying surface sediments in a coastal upwelling region. The surface waters upwelling on the shelf off Peru are mainly fed by southward flowing subsurface waters along the coast, which show a mean ?30Si of +1.5‰. The concentration of dissolved silicic acid (Si(OH)4) increases towards the south in these waters and with increasing water depth, suggesting lateral mixing with water masses from the south and intense remineralisation of particulate biogenic silica (bSiO2) in the water column and in the surface sediments. Surface waters in the realm of the most intense upwelling between 5°S and 15°S have only marginally elevated ?30Si values (?30Si = +1.7‰) with respect to the source Si isotope composition, whereas further north and south, where upwelling is less pronounced, surface waters are more strongly fractionated (?30Si up to +2.8‰) due to the stronger utilisation of the smaller amounts of available Si(OH)4. The degree of Si(OH)4 utilisation in the surface waters along the shelf estimated from the Si(OH)4 concentration data ranges from 51% to 93%. The ?30Sidiatom values of hand-picked diatoms in the underlying surface sediments vary from +0.6‰ to +2.0‰, which is within the range of the expected fractionation between surface waters and diatoms. The fractionation signal in the surface waters produced during formation of the diatoms is reflected by the ?30Sidiatom values in the underlying sediments, with the lowest ?30Sidiatom values in the main upwelling region. The silicon isotope compositions of bSiO2 (?30Si) from the same surface sediment samples are generally much lower than the ?30Sidiatom signatures indicating a significant contamination of the bSiO2 with biogenic siliceous material other than diatoms, such as sponge spicules. This shift towards lighter ?30Si values by up to -1.3‰ compared to ?30Sidiatom signatures for the same surface sediment samples potentially biases the interpretation of ?30Si paleorecords from sediments with low bSiO2 concentrations, and thus the reconstruction of past Si(OH)4 utilisation in surface waters.

Ehlert, Claudia; Grasse, Patricia; Mollier-Vogel, Elfi; Böschen, Tebke; Franz, Jasmin; de Souza, Gregory F.; Reynolds, Ben C.; Stramma, Lothar; Frank, Martin

2012-12-01

403

Heavy metal concentrations in water, suspended matter, and sediment from Gökova Bay, Turkey  

Microsoft Academic Search

The contents of heavy metals (Fe, Mn, Pb, Cu, Cd, and Hg) dissolved in water and suspended solids of Gökova Bay—partly and\\u000a fully sampled in 2005 and 2006, respectively—are quite higher than the average values encountered in uncontaminated sea water.\\u000a The high concentrations are associated with terrestrial inputs from the mining zones and anthropogenic (domestic + industrial)\\u000a sources. Moreover, the

Nuray Balkis; Abdullah Aksu; Erdo?an Oku?; Re?at Apak

2010-01-01

404

Simultaneous Investigation of Sediment Transport and Water Quality Parameters Using An In Situ Measurement Device  

NASA Astrophysics Data System (ADS)

Though quality of surface waters has improved remarkably over the last twenty years, the contaminant load of soft cohesive sediments remained comparatively unimproved. That is why the new European water framework directive addresses contaminant loaded sediments and postulates criteria for assessing sediment quality. Surveys into contaminated sediment behaviour have revealed adsorption/desorption characteristics of individual toxins. Biomonitoring of pollutant pressure on specific benthic organ- isms on the other hand can be useful to elucidate potential dangers to aquatic ecosys- tems. However, it is yet unknown how a given contaminant loaded sediment will re- spond to different hypercritical flow conditions in terms of release rates and partition- ing of xenobiotica. On this account a small in situ measuring device (EROSIMESS) was constructed, that features simultaneous determination of suspended sediment con- centration (optical turbidity meter), dissolved oxygen levels, pH and temperature (membrane probes) under predefined hydraulic conditions. Samples of the suspen- sion can be withdrawn for subsequent chemical analysis. Bottom shear stresses up to 5N/m2 can be generated by means of a propeller that resides in cylindrical perspex tube (erosion chamber) two centimeters above the sediment bed. Baffles on the in- ner wall of the cylinder prevent a solid body rotation of the suspension by creating additional turbulence and a second propeller straight beneath the concentration me- ter inhibits the development of a concentration gradient within the chamber. A small CCD-camera is used to control positioning of the device. It can be used in water- depths up to 5m. The control unit consists of a trigger box and an ordinary laptop computer running LabView. EROSIMESS has been successfully used in various stud- ies on contaminant release, eutrophication, and SOD (sediment oxygen demand) in rivers (Spree: Germany; Maun: UK), reservoirs (Heimbach, Haus Ley: Germany), and lakes (Lea Marston: UK). Selected results from these investigations will be presented.

Prochnow, J. V.

405

Sediment, nutrient and water losses by water erosion under agroforestry systems in the semi-arid region in northeastern Brazil  

Microsoft Academic Search

Inadequate soil management practices adopted in the Brazilian semi-arid region contribute to erosive processes. Agroforestry\\u000a systems (AFs) have been considered an alternative to reduce water erosion. This study aimed to evaluate the impact of two\\u000a alternatives AFs, a traditional and an intensive cropping system on the losses of sediments, water, organic carbon and nutrients\\u000a caused by water erosion in comparison

Maria Ivanilda de Aguiar; Stoécio Malta Ferreira Maia; Francisco Alisson da Silva Xavier; Eduardo de Sá Mendonça; João Ambrósio Araújo Filho; Teógenes Senna de Oliveira

2010-01-01

406

Measured and modelled effects of temperature, dissolved oxygen and nutrient concentration on sediment-water nutrient exchange  

Microsoft Academic Search

Empirical models of sediment-water fluxes of NH4+, NO3- were and PO43- were formed based on published reports. The models were revised and parameters evaluated based on laboratory incubations of sediments collected from Gunston Cove, VA. Observed fluxes ranged from — 18 (sediments uptake) to 276 (sediment release) mg NH4+ m-2 day-1, -17 to -509 mg NO3- m-2 day-1, and -16.4

Carl F. Cerco

1989-01-01

407

Biphasic Extracellular Proteolytic Enzyme Activity in Benthic Water and Sediment in the Northwestern Mediterranean Sea  

PubMed Central

In this study, we used the fact that bacteria are able to cleave a fluorogenic substrate analog (l-leucine-7-amido-4-methylcoumarin) to determine the maximal ectoproteolytic activities (Vm) and affinities (Km) of natural benthic microbial communities by the multiconcentration kinetic method. This investigation was performed during the winter and summer of 1997 with a set of 36 samples of near-bottom water and sediment collected from a coastal area and an offshore area in the western part of the Gulf of Lions. The existence of biphasic microbial ectoproteolysis was statistically confirmed for both the near-bottom water and the sediment, regardless of the spatial and seasonal conditions. Globally, 72.2% of the entire set of bacterial consortia collected at the water-sediment boundary layer showed biphasic microbial kinetics. A specific estimator of the biphasicity indicated that deep benthic bacterial consortia responded better with episodic nutrient supplies than shallower benthic bacterial consortia responded.

Tholosan, Olivier; Lamy, Francois; Garcin, Jean; Polychronaki, Thalia; Bianchi, Armand

1999-01-01

408

Diffusive release of uranium from contaminated sediments into capillary fringe pore water.  

PubMed

Despite remediation efforts at the former nuclear weapons facility, leaching of uranium (U) from contaminated sediments to the ground water persists at the Hanford site 300 Area. Flooding of contaminated capillary fringe sediments due to seasonal changes in the Columbia River stage has been identified as a source for U supply to ground water. We investigated U release from Hanford capillary fringe sediments by packing sediments into reservoirs of centrifugal filter devices and saturating them with Columbia River water for 3 to 84days at varying solution-to-solid ratios. After specified times, samples were centrifuged. Within the first three days, there was an initial rapid release of 6-9% of total U, independent of the solution-to-solid ratio. After 14days of reaction, however, the experiments with the narrowest solution-to-solid ratios showed a decline in dissolved U concentrations. The removal of U from the solution phase was accompanied by removal of Ca and HCO(3)(-). Geochemical modeling indicated that calcite could precipitate in the narrowest solution-to-solid ratio experiment. After the rapid initial release in the first three days for the wide solution-to-solid ratio experiments, there was sustained release of U into the pore water. This sustained release of U from the sediments had diffusion-limited kinetics. PMID:23041367

Rod, Kenton A; Wellman, Dawn M; Flury, Markus; Pierce, Eric M; Harsh, James B

2012-09-13

409

Sediment\\/water and octanol\\/water equilibrium partitioning of volatile organic compounds: temperature dependence in the 2–25°C range  

Microsoft Academic Search

The sediment\\/water (Kd) and octanol\\/water (Kow) equilibrium partitioning coefficients have been investigated for volatile chlorinated and monocylic aromatic hydrocarbons in the 2 to 25°C temperature range. The equilibrium partitioning in closed systems (EPICS) method has been optimized to measure both equilibrium partitioning coefficients. Sediment\\/water equilibrium partitioning for a riverine sediment (organic carbon fraction 4.12%) proved to increase with increasing temperature,

J. Dewulf; H. Van Langenhove; S. Graré

1999-01-01

410

Reactivity of recently deposited organic matter: Degradation of lipid compounds near the sediment-water interface  

NASA Astrophysics Data System (ADS)

The usefulness of biomarker compounds buried in marine sediments depends upon a quantita tive understanding of the effects of early diagenesis on their distribution. To address this, a new experimental approach was utilized to determine rates of degradation in a coastal sediment. Rates of degradation for solvent-extractable lipid components were quantified in four sediment horizons composed of newly accumulated organic matter (31-144 days since deposition). Sediment accumulation rate data derived from changes in the inventory of Be-7 ( t 1/2 = 53.3 days) were combined with concentration data for lipid biomarker compounds, enabling us to evaluate the reactivity of organic matter in the upper 8 cm of the rapidly accumulating sediments of Cape Lookout Bight, North Carolina, USA (CLB). Net rates of loss and rate constants were calculated for individual compounds belonging to three classes of lipids: fatty acids, sterols, and n-alkanes. Individual components showed a range in reactivity, in some cases (fatty acids), attributable to differences in their biological sources. Rates and rate constants were consistently highest in the surficial sediments (0-2.5 cm), indicating that the reactivity of a given molecule(s) decreases over time, and beginning soon after deposition. Comparison with apparent rate constants ( k') calculated over longer timescales (one and ten years) shows that steady-state diagenetic models underestimate rates of degradation at or near the sediment-water interface by an order of magnitude.

Canuel, Elizabeth A.; Martens, Christopher S.

1996-05-01

411

Changes in hyporheic exchange, water temperature and macroinvertebrates following sediment-filled dam removal  

NASA Astrophysics Data System (ADS)

Solute transport across the sediment-water interface is strongly affected by the volume, composition, and morphology of in-channel sediment. Given the dynamic nature of sediment movement it is often difficult to directly evaluate the effects of sediment loading on solute transport and related physical or biological processes. One situation where these effects can be evaluated is after the removal of a sediment-filled dam. In this paper, we describe downstream changes in hyporheic exchange, diurnal temperature flux, and benthic macroinvertebrate community composition following the removal of a small sediment-filled dam in Oregon. Dam removal increased downstream turbidity for short periods of time as fine sediment eroded from the reservoir and reduced hyporheic exchange by less than 30%, but produced no discernable changes in diurnal temperature or macroinvertebrates. Deposition of 470 m3 of gravel and cobble from the upstream reservoir produced a greater than 50x increase in hyporheic residence time, significantly reduced diurnal temperature fluctuations through the downstream reach, and had lasting impacts to the macroinvertebrate community.

Stewart, G. B.; Grant, G. E.

2006-12-01

412

Environmental pollution impact on water and sediments of Kumaun lakes, Lesser Himalaya, India: a comparative study  

NASA Astrophysics Data System (ADS)

A study of the water and sediment chemistry of the Nainital, Bhimtal, Naukuchiyatal and Sattal Lakes of Kumaun, has shown that the water of these lakes are alkaline and that electrical conductivity, total dissolved solid and bicarbonate HCO{3/-} are much higher in Nainital than in the other three lakes. The weathering of limestone lithology and anthropogenic pollution, the latter due to the very high density of population in the Nainital valley, are the primary sources of enhanced parameters. The low pH of Nainital Lake water is due to low photosynthesis and enhanced respiration, increasing CO2 in the water and the consequent enhancement of Ca2+ and HCO{3/-}. The dissolved oxygen in Nainital Lake is less compared to other lakes, indicating anoxic conditions developing at the mud water interface at depth. The PO{4/3-} content in Nainital is higher (124 ?g/l), showing an increasing trend over time leading to eutrophic conditions. The trace metals (Cu, Co, Zn, Ni, Mn, and Sr) are present in greater amounts in the water of Nainital Lake than in the other three lakes, though Fe and Cr are high in Bhimtal and Fe in Naukuchiyatal. The higher abundance is derived from the leaching of Fe Mg from metavolcanic and metabasic rocks. Most of the heavy metals (Cr, Ni, Cu, Mn, Fe, Sr, and Zn) significantly enrich the suspended sediments of the lakes compared to the bed sediments which due to their adsorption on finer particles and owing to multiple hydroxide coating and organic content, except for Fe, which is enriched in the bed sediments. The high rate of sedimentation, 11.5 mm/year in Nainital, compared to Bhimtal with 4.70 mm/year, Naukuchiyatal with 3.72 mm/year, and Sattal with 2.99 mm/year, has resulted in shorter residence time, poor sorting of grains, and lesser adsorption of heavy metals, leading consequently, their depletion in the bed sediments of Nainital Lake.

Das, Brijraj K.

2005-12-01

413

Biocenotic characteristics of some Yucatan lentic water bodies based on invertebrate remains in sediments  

Microsoft Academic Search

The Yucatan Peninsula is a karstic environment with almost no permanent surface water flows. All freshwater lentic systems\\u000a here are supported by underground water. We examined sediments, obtained with an Eckman dredge, from 25 different types of\\u000a water bodies (sinkholes or cenotes, lagoons, and wetlands), to investigate their biocenotic characteristics. All systems showed\\u000a differences in their zoocenoses, ostracods being the

N. N. Smirnov; M. Elías-Gutiérrez

2011-01-01

414

A Coupled Biogeochemical Reactive Transport Model in Bed Sediments and Water Column of Riverine Systems  

NASA Astrophysics Data System (ADS)

ABSTRACT: A multi-scale, quasi-two-dimensional, biogeochemical reactive theoretical and numerical model is presented, able to simulating sediment associated transport and transformations of contaminants in the water column and bed sediments of riverine systems as a result of sediment associated transport, as well as resuspension, deposition and burial. The model considers contaminant mass exchange between sediments and aqueous phase both in benthic sediments and water column as a kinetically controlled process. It also takes into account the effect of microbially-mediated redox reactions affecting the speciation of chemicals. Transport of species in the sediments is modeled using a set of vertical one-dimensional sub-models which take into account the reactive transport of chemicals, burial, sorption/desorption to/from the solid phase, and diffusive transport of aqueous species. An innovative multi-time step approach is used to model the fully kinetic nonlinear reaction terms using a non-iterative explicit method. This approach enables the model to handle fast and near- equilibrium reactions without a significant increase in computational burden. Ongoing and planned applications of this multiscale modeling strategy to two cases, multiple metal transport in Lake Coeur d'Alene, Idaho, and Mercury Cycling in Walker Creek, California, are discussed.

Massoudieh, A.; Bombardelli, F. A.; Sengor, S. S.; Ginn, T. R.

2007-12-01

415

Natural and artificial radionuclides in the Suez Canal bottom sediments and stream water  

NASA Astrophysics Data System (ADS)

Concentration of natural and artificial radionuclides in Suez Canal bottom sediments and stream water have been measured using ? spectrometers based on a hyper-pure Ge detector. The activity concentrations of 238U series, 232Th series and 40K did not exceed 16.0, 15.5 and 500.0 Bq kg-1 dry weight for sediments. The activity concentration of 238U series and 40K did not exceed 0.6 and 18.0 Bq 1-1 for stream water.

El-Tahawy, M. S.; Farouk, M. A.; Ibrahiem, N. M.; El-Mongey, S. A. M.

1994-07-01

416

Heavy metal pollution in water, sediment and fish from the Tigris river in Turkey.  

PubMed

Some heavy metals (Co, Cu, Mo, Ni, Pb, V and Zn) were determined in water, sediments and some fish species (Cyprinion macrostomus and Garra rufa) from the Tigris River. Mo and V were not detected in water and Co, Cu, Ni, Pb, Zn were found low values. Co, Cu, Ni, Pb, V and Zn were found very high levels in the sediments. All the fish samples contain high concentrations of Cu, Ni and Zn, while Co, Mo, Pb and V were not detected. The high concentrations of heavy metals may be directly related to the contamination of the Tigris River by Ergani Copper Plant and the geochemical structure of this region. PMID:8044627

Gümgüm, B; Unlü, E; Tez, Z; Gülsün, Z

1994-07-01

417

Influence of an adjuvant on the distribution of herbicides in a sediment/water system.  

PubMed

This study concerned the influence of a mineral oil adjuvant used as tank-mix, on the sorption of commercially formulated compounds in soil using a laboratory-scale sediment/water system. The laboratory experiment was conducted with the adjuvant Atpolan 80 EC and the triazine herbicide atrazine and isoxaflutole which belong to the isoxazole class of herbicides. Ditch bed sediment was the medium. Pesticide distribution was measured in the aqueous phase, both in systems with and without the sediment. The proportion of pesticide moving into the sediment layer was depended on physicochemical properties of the compounds, but it was also influenced by the adjuvant in case of atrazine and only slightly in that of isoxaflutole. Atpolan 80 EC also caused an increase of Kd and Koc values of atrazine. PMID:17390786

Swarcewicz, M; Skórska, E

2006-01-01

418

Heavy metals in sediments from canals for water supplying and drainage: mobilization and control strategies.  

PubMed

One of the most critical aspects of the maintenance of canals for water supplying and drainage is the managing of deposited sediments, which must be periodically removed. Deposited sediments, if containing anthropogenic pollutants with a concentration exceeding specific law limits, must be stored as industrial wastes, thus raising additional economic and logistic problems to deal with. Our research considers polluted sediments from an area close to the south side of Po river, in order to characterize heavy metals associated with different mineral species, thus defining effective treatments for their inertization, and suggesting a possible process for their recycle. Our results demonstrate that the composition of these sediments is suitable for the production of tiles and bricks. Several tests were thus performed to optimize sample treatment and other process parameters, finally giving very encouraging results. Releasing tests on fired products reveal that all the heavy metals are well retained. PMID:18486335

Malferrari, Daniele; Brigatti, Maria Franca; Laurora, Angela; Pini, Stefano

2008-04-11

419

Modeling water and sediment contamination of Lake Pontchartrain following pump-out of Hurricane Katrina floodwater.  

PubMed

Levee failure and overtopping as a result of Hurricane Katrina caused major flooding of New Orleans, Louisiana. Floodwaters, which were contaminated with heavy metals, organic chemicals, and fecal coliform bacteria (FCB), were pumped into neighboring Lake Pontchartrain during dewatering. The impact of levee failure on water and benthic sediment concentrations in the lake was investigated by applying a numerical water quality model coupled to a three-dimensional, numerical hydrodynamic model. The model was used to compute water and benthic sediment concentrations throughout the lake for lead, arsenic, benzo(a)pyrene (BaP), and 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene (DDE), and water concentrations for FCB. Computed concentrations resulting from actual pumped discharges with levee failure and overtopping were compared to computed concentrations resulting from pumped discharges without levee failure or overtopping, and concentrations from both sets of conditions were compared to ecological water and sediment quality screening guideline values. The model indicated that incremental increases above pre-Katrina benthic sediment concentrations are about a factor of 10 greater with dewatering of the floodwaters than with dewatering of storm water without flooding. However, these increases for the metals are small relative to pre-Katrina concentrations. The results showed that the ecological screening-level sediment quality guideline values were exceeded for BaP and DDE in areas near the south shoreline of the lake as a result of floodwater pump-out, whereas, this was not the case for storm water removal without flooding. The model showed that lake water column concentrations should be about the same during both dewatering conditions regardless of whether there is flooding or not. PMID:17399885

Dortch, Mark S; Zakikhani, Mansour; Kim, Sung-Chan; Steevens, Jeffery A

2007-03-30

420

Is upper water column productivity reflected in marine sediments? A biomarker perspective  

NASA Astrophysics Data System (ADS)

Biomarker concentrations and distributions in sediments are increasingly used in paleoceanographic research to track changes in marine paleoproductivity and phytoplankton assemblages. Organic Matter (OM) and biomarkers exported from surface waters can be altered through the water column, in surface sediments and during subsequent burial and diagenesis. The multiple processes controlling preservation of OM/biomarkers remain poorly understood and only a few studies have specifically compared water column biomarker assemblages with those preserved in underlying sediments (e.g. Wakeham et al. 2002). A better understanding of these processes is needed if biomarkers are to be used to track export productivity in the past. In this study, we compare phytoplanktonic biomarker distributions (including sterols, alkyl diols, and alkenones) in surface water suspended organic matter (SOM) with that of underlying sediments, collected along a transect in the Southeast Atlantic Ocean, off South Africa, during the 2010 UK-GEOTRACES expedition. The transect spans the shelf-slope-basin transition, such that the studied sediments have been deposited under a range of increasing water depths and variable bottom water oxygen concentrations with distance offshore. The latter is reflected by sediment O2 penetration depths, which range from < 1 cm on the shelf slope to >> 6 cm in the Cape Basin. Biomarker distributions are homogeneous in the upper 200 m water column and similar along the transect, suggesting similar water column productivity. However, this signature is significantly altered in underlying sediments, with a variety of trace compounds in surface waters, such as alkenones, dominating in the sediments presumably due to their lower reactivity and preferential preservation. We further evaluate the effect of pore water O2 content on biomarker preservation. Phytoplankton biomarker concentrations are enhanced under the lowest pore water O2 content (from three cores collected under similar depth and productivity regimes) and lowest when pore water O2 concentrations are higher, suggesting that O2 concentration may play an important role in biomarker degradation. This is consistent with previous work in the Arabian Sea by Sinninghe-Damste et al. (2002), who observed different biomarker accumulation rates and selective preservation of different compound classes under oxic versus anoxic conditions. However, the bottom water redox variations presented here are more subtle - even on the shelf slope, bottom water O2 concentration minima are typically >190 ?M (>80% O2 saturated). Thus, our work indicates that even subtle differences in bottom water and sediment redox conditions may significantly impact biomarker preservation. References Wakeham, S. G., et al. (2002), Lipid biomarker fluxes in the Arabian Sea, with a comparison to the equatorial Pacific Ocean. Deep Sea Res. II, 49, 2265-2301. Sinninghe-Damste, J. S., et al. (2002), The influence of oxic degradation on the sedimentary biomarker record II. Evidence from Arabian Sea sediments. Geochim. Cosmochim. Acta, 66, 2732-2754

Hernandez-sanchez, M.; Homoky, W. B.; Pancost, R. D.; Mills, R. A.; Thomas, A. L.; Henderson, G.

2011-12-01

421

Housing Standards: Change to HUD 4930.2 Intermediate Minimum Property Standard (IMPS) Supplement for Solar Heating and Domestic Hot Water Systems.  

National Technical Information Service (NTIS)

This rule is made to provide an updating, clarification, and improvement of requirements contained in HUD Handbook 4930.2, Intermediate Minimum Property Standards (IMPS) Supplement concerning solar heating and domestic hot water systems. Changes pertain t...

1982-01-01

422

Impacts of sewage of a pulp and paper industry on the sediments of Vigozero water basin  

NASA Astrophysics Data System (ADS)

The studies of sediments of Vigozero reservoir with 1969 for 2009 are presented. Vigozero water basin belongs to pool of the White Sea. It's watershed area is 16 800 km2, water surface area is 1140 km2, volume of lake - 6,46 km3, average depth - 6,2 m, the maximum depth - 23 m, the water residence time -1,14 years. Northern part of Vigozero reservoir tests influence of sewage of Segeja pulp and paper mill, operating since 1938. Zones of pollution of a bottom are allocated: 1- solid waste; 2 - active silt, lignin, cellulose; 3 - transformed suspended solids. Distribution and stratification of deposits, their physical and chemical parameters is investigated. It is shown, that change of a chemical compound of sediments is connected with volume and qualitative of sewage. The tendency to the extension of polluted zones and to spreading of organic pollution all the bottom is considered. Maximum settling velocity was fixed in 1980 -1985. Accumulation of the organic compounds in sediments at that time resulted in the development of high internal loading. Change of an ecological situation in Vigozero water basin, connected with falling volumes of manufacture last 20 years, has affected sediment genesis processes, therefore the concentrations of organic substances and biogenic elements have decreased in a superficial layer of sediments, concentration of iron has increased. Now, transformation of the organic substances, which have been saved up earlier, demands significant amounts of oxygen. Variability of pH and Eh of sediments indicates unstable oxidation-reduction conditions. Ore formations on a redox-barrier interfere with transport of substances from deposits in water. The work was supported in part by Russian Foundation for Basic Research (grant ? 08-05-98811).

Natalia, Belkina

2010-05-01

423

Water and sediment transport of channel-flat systems in a mesotidal mudflat: Willapa Bay, Washington  

NASA Astrophysics Data System (ADS)

The muddy tidal flats of southern Willapa Bay, Washington are tidally dominated and receive little direct freshwater input. We use data from instruments deployed in channels of different size and on their adjacent flats to investigate the hydrodynamics and sediment dynamics of each morphological setting under a range of seasonal and meteorological conditions, including rain and wind events. Interaction between the morphology of the channel/flat complex and tidal water-level variations produces well-defined velocity pulses during both flooding and ebbing tides. These pulses represent about 27% of the total along-channel water transport and 35% of the suspended-sediment transport of the system. Maintenance of continuity produces the velocity pulse, and pulse magnitude is determined by tidal range. Wind alters the flow regime in channels and on the flat, enhancing over-flat ebb flow in this study location while decreasing ebb-pulse intensity. Wind speed was positively correlated with minimum suspended-sediment concentration. Precipitation falling directly on flats was found to erode flat sediment, which subsequently formed a temporary deposit in the adjacent channel. Residual along-channel water transport in channels and on nearby flats was flood dominant under all seasonal conditions sampled, and sediment flux was flood dominant during winter and spring deployments.

Nowacki, Daniel J.; Ogston, Andrea S.

424

Local scale marine modelling of Fukushima releases. Assessment of water and sediment contamination and sensitivity to water circulation description.  

PubMed

The dispersion of (137)Cs released from Fukushima nuclear power plant to the sea after the March 11th 2011 tsunami has been studied using numerical models. The 3D dispersion model consists of an advection/diffusion equation with terms describing uptake/release reactions between water and seabed sediments. The dispersion model has been fed with daily currents provided by HYCOM and JCOPE2 ocean models. Seabed sediment (137)Cs patterns obtained using both current data set have been compared. The impact of tides and of atmospheric deposition has been evaluated as well. It has been also found that a 2-step kinetic model (two consecutive reversible reactions) for describing water/sediment interactions produces better results than a 1-step model (one single reversible reaction). PMID:23021937

Periáñez, R; Suh, Kyung-Suk; Min, Byung-Il

2012-09-27

425

Comparison of whole-sediment, elutriate and pore-water exposures for use in assessing sediment-associated organic contaminants in bioassays  

SciTech Connect

Bioassays have frequently been used as tools to simulate exposure of benthos to sediment-associated contaminants in hazard assessments. Due to the problems involved with estimating bioavailability in whole-sediment bioassays, aqueous fractions such as elutriates and pore water have been substituted for whole-sediment exposures. The objective of this research was to compare and evaluate the bioavailability of representative neutral hydrophobic contaminants in whole sediments and in aqueous extracts of whole sediment in simultaneous bioassays, using three representative indicator species, Diporeia spp., Chironomus riparius larvae, and Lumbriculus variegatus. Aqueous extracts of whole sediment did not accurately represent the exposure observed in whole sediment. Generally, the aqueous extracts underexposed organisms compared to whole sediment, even after adjusting accumulation to the fraction of organic carbon in the test media. Accumulation comparisons among whole-sediment, elutriate, and pore-water exposures depended on sampling time. At some sampling times for some contaminants, differences in accumulation between a particular aqueous extract and whole sediment were not significant; however, these similarities were not observed for all species at the particular sampling time. Bioaccumulation and contaminant clearance data suggest that a number of factors such as the indicator species, exposure media, and chemical/physical properties of individual contaminants are responsible for the accumulation differences observed among the tested media. Normalizing bioaccumulation to the amount of organic carbon in a source compartment adjusted for bioavailability differences of only some contaminants. The authors suggest that the bioavailability of contaminants such as those tested cannot be accurately predicted in bioassays that expose organisms to aqueous representations of whole sediment.

Harkey, G.A. (Great Lakes Environmental Research Lab., Ann Arbor, MI (United States) Clemson Univ., Pendleton, SC (United States)); Landrum, P.F. (Great Lakes Environmental Research Lab., Ann Arbor, MI (United States)); Klaine, S.J. (Clemson Univ., Pendleton, SC (United States))

1994-08-01

426

Characterization of sediment pore-water dissolved organic matter of lakes by high-performance size exclusion chromatography  

Microsoft Academic Search

This paper demonstrates the applicability of high-performance size exclusion chromatography (HPSEC) to characterize lake-sediment pore-water dissolved organic matter (DOM). Two shallow nonstratified Estonian lakes – Harku and Karujärv – were investigated. The HPSEC results for pore waters were compared with those obtained by spectroscopic methods such as fluorescence spectroscopy and UV-absorption, and with other analyses carried out on sediments (sediment

Viia Lepane; Aina Leeben; Olga Malashenko

2004-01-01

427

Short term changes in pore water chemistry in river sediments during the early colonization by Vallisneria spiralis  

Microsoft Academic Search

This study aims to investigate the effects of benthic vegetation colonization on pore water chemistry in river sediments with\\u000a different organic matter and nutrient loadings. Shoots of Vallisneria spiralis L., surface sediments and water were collected in March 2009 from two fluvial reaches, upstream (U) and downstream (D) an urban\\u000a wastewater treatment plant. Laboratory microcosms were created with homogenised sediments

Marco Bartoli; Cristina Ribaudo; Daniele Longhi; Luciana E. Q. Brito; Mariachiara Naldi; Paola Iacumin; Pierluigi Viaroli

2010-01-01

428

Water and sediment dynamics at Saint Lawrence River mouth  

Microsoft Academic Search

The main features of the hydrological regime and morphological structure of the estuarine-type mouth area of the Saint Lawrence\\u000a River are considered. Data on the structure of water masses, thermal and ice regimes in the Gulf of Saint Lawrence, which\\u000a has a significant effect on the estuary, are given. The major attention is paid to water mixing processes, water and

E. N. Dolgopolova; M. V. Isupova

2011-01-01

429

Sediment dynamic at the water-sediment interface of the Thau Lagoon (S. France) from seasonal to century time scales using radiogenic and comosgenic nuclides  

NASA Astrophysics Data System (ADS)

Among the factors disturbing the sedimentary record the most important are massive sediment displacement, erosion, bioturbation, and human activities. As a part of the PNEC supported Microbent programme, we investigated sedimentation processes to determine sediment deposit/erosion cycle at the water-sediment interface in relation with these potential perturbations. The investigated area is the Thau Lagoon, located in the south of France and strongly influenced by human activities (Sete industrial harbour, oyster farming). Two main sites were investigated: C4 in the middle of the lagoon in order to have a reference site, C5 nearby oyster farming. Sediment cores, up to 50cm in length, were collected in Dec. 2001, April, July and August 2002. Interface sediments have been studied using classical sedimentological parameters (radiography, grain size distribution) and analysis of the radionuclides Th-234, Be-7, Pb-210 and Cs-137 (gamma and alpha spectrometry). On a century time scale, 210Pb and 137Cs profiles indicate well defined sedimentation rates at both sites (around 0.2 0.3 cm per year). Nevertheless at the central site, C4, cores seem to register episodic changes in mean granulometry, presenting recurrently peaks. The upper 10 cm of Pb-210 profiles at site C5 exhibit a mixed layer associated with coarser sediments: these could be in relation with biological or dredging activity. On a seasonal time scale, Th-234 and Be-7 both show seasonal variations in activities and in penetration within the sediment. As these radionuclides are mainly carried by the fine particles, such variations must reflected associated variations of silt content of surface sediments. Fine sediment accumulation is a balance between deposition (settling, bioaccumulation) and erosion. Summer period seems to correspond to the most favourable season for deposition for the Thau lagoon. This study clearly illustrates the interest of radionuclides of different input and half-life to describe in details processes like sediment accumulation, bioturbation, erosion / deposition at different time scales.

Jouanneau, J.-M.; Schmidt, S.; Weber, O.; Lecroart, P.; Radakovitch, O.; Gilbert, F.; Jezequel, D.

2003-04-01

430

Water selenium speciation and sediment fractionation in a California flow-through wetland system  

USGS Publications Warehouse

A flow-through wetland system was established in the Tulare Lake Drainage District (TLDD) in California to determine if selenium (Se) from saline irrigation drainage can be removed prior to impoundment in evaporation basins to reduce potential toxicity to waterbirds. The objective of this research was to evaluate Se speciation, accumulation, and fractionation in the waters and sediments of the newly developed wetland system. The inlet water was dominated by selenate [Se(VI), 92%], with smaller percentages of selenite [Se(IV), 5%] and organic Se [org-Se(-II), 3%]. For the outflow water, the average percentage of Se(VI) was 72% in November 1997 and 59% in February 1999. This change may be due to an increase in either residence time and/or accumulation of organic detrital matter, which may enhance Se(VI) reduction processes. Selenium accumulation, transformation, and incorporation with the solid phase were all intensified in the surface sediment (<20 cm). The highest total Se concentrations in the sediments were found in the top 5 cm and concentrations dramatically decreased with depth. Elemental Se [Se(0)], as extracted by Na2SO3, was the largest fraction (average of 46%) of the total sediment Se, followed by organic matter-associated Se (OM-Se) extracted by NaOH (average of 34%). Soluble, adsorbed, and carbonate-associated Se, as extracted by KCl, K2HPO4 (pH 8.0), and NaOAc (pH 5.0), were about 3, 10, and 3% of the total sediment Se, respectively. After establishing the wetland for 2 yr, significant Se removal from the flowing water was observed. The major sink mechanisms in the sediment are reduction to Se(0) and immobilization into the organic phase.A flow-through wetland system was established in the Tulare Lake Drainage District (TLDD) in California to determine if selenium (Se) from saline irrigation drainage can be removed prior to impoundment in evaporation basins to reduce potential toxicity to waterbirds. The objective of this research was to evaluate Se speciation, accumulation, and fractionation in the waters and sediments of the newly developed wetland system. The inlet water was dominated by selenate [Se(VI), 92%], with smaller percentages of selenite [Se(IV), 5%] and organic Se [org-Se(-II), 3%]. For the outflow water, the average percentage of Se(VI) was 72% in November 1997 and 59% in February 1999. This change may be due to an increase in either residence time and/or accumulation of organic detrital matter, which may enhance Se(VI) reduction processes. Selenium accumulation, transformation, and incorporation with the solid phase were all intensified in the surface sediment (<20 cm). The highest total Se concentrations in the sediments were found in the top 5 cm and concentrations dramatically decreased with depth. Elemental Se [Se(0)], as extracted by Na2SO3, was the largest fraction (average of 46%) of the total sediment Se, followed by organic matter-associated Se (OM-Se) extracted by NaOH (average of 34%). Soluble, adsorbed, and carbonate-associated Se, as extracted by KCl, K2HPO4 (pH 8.0), and NaOAc (pH 5.0), were about 3, 10, and 3% of the total sediment Se, respectively. After establishing the wetland for 2 yr, significant Se removal from the flowing water was observed. The major sink mechanisms in the sediment are reduction to Se(0) and immobilization into the organic phase.

Gao, S.; Tanii, K. K.; Peters, D. W.; Herbel, M. J.

2000-01-01

431

Monitoring the impact of urban effluents on mineral contents of water and sediments of four sites of the river Ravi, Lahore.  

PubMed

We assessed the impact of urban effluents on the concentrations of selected minerals (Cd, Cr, Cu, Fe, Pb, Zn, Mn, Ni, and Hg) in river Ravi before and after its passage through Lahore city. Water and sediment samples were collected from three lowly to highly polluted downstream sites (Shahdera (B), Sunder (C), and Balloki (D)) alongside the least polluted upstream site (Siphon (A)) during high and low river flow seasons. All the mineral concentrations increased up to site C but stabilized at site D, showing some recovery as compared to the third sampling site. The trend of mean mineral concentration was significantly higher during the low than the high flow season at all the sites. The mean Hg concentrations approached 0.14 and 0.12 mg/l at site A which increased (%) up to 107 and 25 % at site B, 1,700 and 1,317 % at site C, and 1,185 and 1,177 % at site D during low and high river flows, respectively. All mineral concentrations were much higher in the sediment than the water samples. Mean Cd (917 %), Cr (461 %), Cu (300 %), Fe (254 %), Pb (179 %), Zn (170 %), Mn (723 %), Ni (853 %), and Hg (1,699 %) concentrations were higher in riverbed sediments sampled from site C in comparison with the sample collected at site A during low flow season. The domestic and industrial discharges from Lahore city have created undesirable water qualities during the low river flow season. As majority of the mineral levels in the river Ravi were higher than the permissible and safe levels, this is of immediate concern for riverine fish consumers and the users of water for recreation and even irrigation. The use of these waters may pose health risks, and therefore, urgent intervention strategies are needed to minimize river water pollution and its impact on fish-consuming communities of this study area and beyond. PMID:23793567

Shakir, Hafiz Abdullah; Qazi, Javed Iqbal; Chaudhry, Abdul Shakoor

2013-06-22

432

The fluidity of boulder debris flows is affected by fine sediment in the pore water  

NASA Astrophysics Data System (ADS)

Basic equations for debris flows are frequently derived using the simple assumption of monogranular particles. However, actual debris flows include a great diversity of grain sizes, resulting in inherent features such as inverse grading, particle size segregation, and liquefaction of fine sediment. The liquefaction of fine sediment affects the fluidity of debris flows, although the behavior and influence of fine sediment in debris flows have not been examined sufficiently. This study used flume tests to detect the effect of fine sediment on the characteristics of laboratory debris flows consisting of particles with two diameters: one diameter was fixed at a large particle size, while the small diameters were varied with the experimental conditions. From the experiments, the greatest sediment concentration and flow depth were observed in the debris flows mixed with finer sediment, indicating increased flow resistance. Then, the experimental friction coefficient was compared with the theoretical friction coefficient derived by substituting the experimental values into the constitutive equations for debris flow. The theoretical friction coefficient was obtained from two models with different fine-sediment treatments: one assuming that all of the fine sediments were solid particles and the other that the particles consisted of a fluid phase involving pore water liquefaction. A discriminant index was introduced to clarify which contribution from the two models could better explain the experimental results. The comparison of the friction coefficients detected a fully liquefied state for the finest particle mixture with sediment. However, even with the same particle size, the debris flows could be regarded as a liquefied state, a solid state, or a partially liquefied transition state depending on the experimental conditions other than the sediment particle size. These results infer that the liquefaction of fine sediment in debris flows was induced not only by the geometric conditions that allowed small particles to be stored in the interstitial space of large particles but also by the flow conditions: i.e., "fine sediment" and "coarse grain" in the debris flows of mixed particle sizes can be defined according to the kinematic conditions.

Hotta, Norifumi; Kaneko, Takahiro; Iwata, Tomoyuki; Nishimoto, Haruo

2013-04-01

433

Surface water quality in Manitoba with respect to six chemical parameters, water body and sediment type and land use  

Microsoft Academic Search

Surface waters at 425 sites in Manitoba were analyzed for total dissolved solids, nitrate-nitrogen, dissolved organic matter, cadmium, lead and copper. Regional differences in chemical parameters were found for various areas of the province and for some bottom sediment types. Sites were classified according to predominant type of land use: minimal, cropland, livestock, mining, recreation, forest logging, hydroelectric development and

E. Pip

2005-01-01

434

Phase and chemical equilibria in the system surface water-bottom sediments with regard to industrial pollution  

SciTech Connect

The chemical composition of water and bottom sediments of four ponds without outflow, situated in St. Petersburg, has been quantitatively analyzed. A thermodynamic algorithm has been developed for calculating the detailed composition of the water and inorganic constituent of the bottom sediments taking into account possible acid-base and redox equilibria.

Kurilenko, V.V.; Charykov, N.A.; Puchkov, L.V. [St. Petersburg State Univ. (Russian Federation)

1995-11-10

435

Modeling the sensitivity of sediment and water runoff dynamics to Holocene climate and land use changes at the catchment scale  

Microsoft Academic Search

An increasing number of studies have indicated that soil erosion, sediment redistribution and water discharge during the Holocene have varied greatly under influence of environmental changes. In this paper we have used a modeling approach to study the driving forces for soil erosion and sediment redistribution on the one hand, and water discharge on the other hand, during the Holocene

Bastiaan Notebaert; Gert Verstraeten; Philip Ward; Hans Renssen; Anton Van Rompaey

2011-01-01

436

Solar heating, cooling, and domestic hot water system installed at Kaw Valley State Bank and Trust Company, Topeka, Kansas  

NASA Astrophysics Data System (ADS)

The building has approximately 5600 square feet of conditioned space. Solar energy was used for space heating, space cooling, and preheating domestic hot water (DHW). The solar energy system had an array of evacuated tube-type collectors with an area of 1068 square feet. A 50/50 solution of ethylene glycol and water was the transfer medium that delivered solar energy to a tube-in-shell heat exchanger that in turn delivered solar heated water to a 1100 gallon pressurized hot water storage tank. When solar energy was insufficient to satisfy the space heating and/or cooling demand, a natural gas-fired boiler provided auxiliary energy to the fan coil loops and/or the absorption chillers. Extracts from the site files, specification references, drawings, and installation, operation and maintenance instructions are presented.

1980-11-01

437

Iron and manganese diagenesis in deep sea volcanogenic sediments and the origins of pore water colloids  

NASA Astrophysics Data System (ADS)

Volcanogenic sediments are typically rich in Fe and Mn-bearing minerals that undergo substantial alteration during early marine diagenesis, however their impact on the global biogeochemical cycling of Fe and Mn has not been widely addressed. This study compares the near surface (0-20 cm below sea floor [cmbsf]) aqueous (<0.02 ?m) and aqueous + colloidal here in after 'dissolved' (<0.2 ?m) pore water Fe and Mn distributions, and ancillary O2(aq), NO3- and solid-phase reactive Fe distributions, between two volcanogenic sediment settings: [1] a deep sea tephra-rich deposit neighbouring the volcanically active island of Montserrat and [2] mixed biosiliceous-volcanogenic sediments from abyssal depths near the volcanically inactive Crozet Islands archipelago. Shallow penetration of O2(aq) into Montserrat sediments was observed (<1 cmbsf), and inferred to partially reflect oxidation of fine grained Fe(II) minerals, whereas penetration of O2(aq) into abyssal Crozet sediments was >5 cmbsf and largely controlled by the oxidation of organic matter. Dissolved Fe and Mn distributions in Montserrat pore waters were lowest in the surface oxic-layer (0.3 ?M Fe; 32 ?M Mn), with maxima (20 ?M Fe; 200 ?M Mn) in the upper 1-15 cmbsf. Unlike Montserrat, Fe and Mn in Crozet pore waters were ubiquitously partitioned between 0.2 ?m and 0.02 ?m filtrations, indicating that the pore water distributions of Fe and Mn in the (traditionally termed) 'dissolved' size fraction are dominated by colloids, with respective mean abundances of 80% and 61%. Plausible mechanisms for the origin and composition of pore water colloids are discussed, and include prolonged exposure of Crozet surface sediments to early diagenesis compared to Montserrat, favouring nano-particulate goethite formation, and the elevated dissolved Si concentrations, which are shown to encourage fine-grained smectite formation. In addition, organic matter may stabilise authigenic Fe and Mn in the Crozet pore waters. We conclude that volcanogenic sediment diagenesis leads to a flux of colloidal material to the overlying bottom water, which may impact significantly on deep ocean biogeochemistry. Diffusive flux estimates from Montserrat suggest that diagenesis within tephra deposits of active island volcanism may also be an important source of dissolved Mn to the bottom waters, and therefore a source for the widespread hydrogenous MnOx deposits found in the Caribbean region.

Homoky, W. B.; Hembury, D. J.; Hepburn, L. E.; Mills, R. A.; Statham, P. J.; Fones, G. R.; Palmer, M. R.

2011-09-01

438

Novel passive sampling device for measuring sediment-water diffusion fluxes of hydrophobic organic chemicals.  

PubMed

Molecular diffusion across the sediment-water interface, as one of the key geochemical processes, dictates whether a sediment is a source or sink of chemicals, providing useful data in designing remedial actions. Despite ample previous efforts in quantifying sediment-water diffusion fluxes, the resulting methods are largely unsatisfactory. Herein, we introduce a novel passive sampling device capable of measuring vertical profiles of chemical concentrations near the sediment-water interface, from which diffusion fluxes can be calculated based on a model that we developed. In laboratory testing, diffusion fluxes (0.032-310 ng m(-2) d(-1)) of dichlorodiphenyltrichloroethane and its metabolites obtained from the present sampling device were consistent with those (0.38-610 ng m(-2) d(-1)) determined by using a conventional active sampling method, solid-phase extraction/liquid-liquid extraction. Field deployment of the sampling device yielded individual diffusion fluxes of p,p'-DDD, p,p'-DDE, p,p'-DDMU, o,p'-DDMU, p,p'-DDNU, and p,p'-DBP in the range of 5.9-150 ng m(-2) d(-1), which were comparable to those (5.5-85 ng m(-2) d(-1)) obtained with a benthic chamber. Moreover, diffusion fluxes of p,p'-DDT and o,p'-DDT obtained with the sampling device were negative; i.e., the sediment is acting as a sink for these chemicals, while that could not be found using the benthic chamber. Thus, the passive sampling device can provide better information about the movement of chemicals through the sediment and overlying water for the choice of remedial strategies. PMID:23919591

Liu, Hui-Hui; Bao, Lian-Jun; Zhang, Kai; Xu, Shi-Ping; Wu, Feng-Chang; Zeng, Eddy Y

2013-08-20

439

NUMERICAL MODELING OF WATER QUALITY AND SEDIMENT RELATED PROCESSES  

Technology Transfer Automated Retrieval System (TEKTRAN)

A three-dimensional water quality model was developed for simulating temporal and spatial variations of water quality with respect to phytoplankton, nutrients, and dissolved oxygen. Four major interacting systems were simulated, including phytoplankton dynamics, the nitrogen and phosphorus cycles, a...

440

Geotechnical properties of dredged marine sediments treated at high water/cement ratio  

NASA Astrophysics Data System (ADS)

Cement and lime are widely employed in soil and sediment treatment for an improvement of geotechnical properties, such as an increase in mechanical strength which enables beneficial use in various geotechnical applications. In this study, fine organic-rich dredged harbour sediments of 120% relative water content were treated with dry cement at contents varying between 2% and 10% of bulk sediment wet weight. Tests based on assessments of one-dimensional compression and Atterberg limits were performed on untreated and cement-treated sediments for various curing periods, as well as grain-size, SEM and X-ray diffraction analyses. The results confirm that increasing the cement content improves the geotechnical properties of these harbour sediments. Already in the early phase of curing (first 3 days of curing), particle size increases while sediment plasticity decreases. Changes in the compressibility behaviour include an increase in apparent preconsolidation pressure, in the compression index C c and in the primary consolidation coefficient C v, and a decrease in the secondary compression index C_? . This means that the new materials are characterized by a behaviour intermediate between that of fine and that of coarser soils.

Rekik, Boubaker; Boutouil, Mohamed

2009-06-01