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1

Determination of radioactive elements and heavy metals in sediments and soil from domestic water sources in northern peninsular Malaysia.  

PubMed

Soil serves as a major reservoir for contaminants as it posseses an ability to bind various chemicals together. To safeguard the members of the public from an unwanted exposure, studies were conducted on the sediments and soil from water bodies that form the major sources of domestic water supply in northern peninsular Malaysia for their trace element concentration levels. Neutron Activation Analysis, using Nigeria Research Reactor-1 (NIRR-1) located at the Centre for Energy Research and Training, Zaria, Nigeria was employed as the analytical tool. The elements identified in major quantities include Na, K, and Fe while As, Br, Cr, U, Th, Eu, Cs, Co, La, Sm, Yb, Sc, Zn, Rb, Ba, Lu, Hf, Ta, and Sb were also identified in trace quantities. Gamma spectroscopy was also employed to analyze some soil samples from the same area. The results indicated safe levels in terms of the radium equivalent activity, external hazard index as well as the mean external exposure dose rates from the soil. The overall screening of the domestic water sources with relatively high heavy metals concentration values in sediments and high activity concentration values in soil is strongly recommended as their accumulation overtime as a consequence of leaching into the water may be of health concern to the members of the public. PMID:21901308

Muhammad, Bashir G; Jaafar, Mohammad Suhaimi; Abdul Rahman, Azhar; Ingawa, Farouk Abdulrasheed

2012-08-01

2

Contaminated Sediments in Water  

MedlinePLUS

... Contact Us Water: Contaminated Sediments You are here: Water Pollution Prevention & Control Sediments Contaminated Sediments in Water Contaminated ... Water Education & Training Grants & Funding Laws & Regulations Our Waters Pollution Prevention & Control Applications & Databases Low Impact Development Impaired ...

3

Domestic wash water reclamation  

NASA Technical Reports Server (NTRS)

System consists of filtration unit, reverse-osmosis module, tanks, pumps, plumbing, and various gauges, meters, and valves. After water is used in washing machine or shower, it is collected in holding tank. Water is pumped through series of five particulate filters. Pressure tank supplies processed water to commode water closet.

Hall, J. B., Jr.; Batten, C. E.; Wilkins, J. R.

1974-01-01

4

STATE OF CALIFORNIA DOMESTIC HOT WATER (DHW)  

E-print Network

STATE OF CALIFORNIA DOMESTIC HOT WATER (DHW) CEC- CF-6R-MECH-01 (Revised 08/09) CALIFORNIA ENERGY COMMISSION INSTALLATION CERTIFICATE CF-6R-MECH-01 Domestic Hot Water (DHW) (Page 1 of 3) Site Address: Enforcement Agency: Permit Number: 2008 Residential Compliance Forms August 2009 1. WATER HEATING SYSTEMS

5

STATE OF CALIFORNIA SOLAR DOMESTIC HOT WATER SYSTEMS (SDHW)  

E-print Network

STATE OF CALIFORNIA SOLAR DOMESTIC HOT WATER SYSTEMS (SDHW) CEC- CF-6R-MECH-02 (Revised 08/09) CALIFORNIA ENERGY COMMISSION INSTALLATION CERTIFICATE CF-6R-MECH-02 Solar Domestic Hot Water Systems (SDHW 2009 SOLAR HOT WATER HEATING SYSTEMS: SRCC Certified Mfr Name & Model Number Net Solar Fraction (from

6

Residential conservation demonstration program: domestic hot water  

SciTech Connect

Four types of domestic hot water (DHW) systems installed in 80 homes throughout Florida are currently monitored by the Florida Solar Energy Center (FSEC) under a demonstration program for the Florida Public Service Commission. DHW systems selected for the program are located in four major population areas of Florida: Jacksonville, Orlando/Brevard County, North Palm Beach/Ft. Lauderdale, and the Tampa Bay region. Twenty systems of each DHW type - conventional electric water heaters, heat pump water heaters, solar hot water systems, and waste heat recovery units - are metered to determine electricity use and hot water energy production. A microcomputer-based data acquisition system collects 15-minute interval data at each site and returns it to FSEC over the telephone network semi-weekly. The data is analyzed to determine the average system efficiency and the time-of-day water and electricity demand profiles. Analysis for the Florida warm season of 1982 indicates that the solar systems and heat recovery units operated with the highest efficiency while the heat pumps performed approximately twice as efficiently as the conventional electric water heaters. The average electrical demand profiles of the solar and heat recovery groups were considerably lower than those for the conventional and heat pump water heaters. The profiles of the latter two systems were similar although the heat pump sample used more hot water than the conventional group. When completed in 1983, the study data will provide a full year comparison of the energy savings and time-of-day impact of each DHW system type.

Merrigan, T.

1982-01-01

7

Reutilization of industrial sedimentation plants as a domestic landfill  

SciTech Connect

The methods and the investigation results for evaluation of the risk potential emanating from the mixed waste landfill Steinsee in Johanngeorgenstadt are described for the protected commodities of water, soil and air. The peculiarity of this mixed waste landfill is its layered structure (17th to 19th century near-surface mineworkings, granite weathering zone at the base of the landfill, washed-in tailings, and refuse dump). A network of measuring points has been installed in and around the landfill, and selective investigations have been made to ascertain the risk potential from the landfill. Based on the investigation results, it can be estimated that the continued use of the landfill is justifiable from the geological, hydrogeological and hydrological viewpoints, provided that permanent and continuous control is ensured by a monitoring system and that the overall situation can be improved in the short term by suitable technical measures. The waste being deposited now consists of domestic refuse, bulky refuse, sewage sludge, building rubble, excavated earth, broken up road surfacing, waste containing asbestos, industrial waste and power station ash.

Viehweg, M.; Duetsch, M.; Wagner, J. [C and E Consulting und Engineering GmbH, Chemnitz (Germany); Edelmann, F. [Landratsamt Westerzgebirgskreis, Schwarzenburg (Germany)

1995-12-31

8

Accounting for Water Insecurity in Modeling Domestic Water Demand  

NASA Astrophysics Data System (ADS)

Water demand management uses price elasticity estimates to predict consumer demand in relation to water pricing changes, but studies have shown that many additional factors effect water consumption. Development scholars document the need for water security, however, much of the water security literature focuses on broad policies which can influence water demand. Previous domestic water demand studies have not considered how water security can affect a population's consumption behavior. This study is the first to model the influence of water insecurity on water demand. A subjective indicator scale measuring water insecurity among consumers in the Palestinian West Bank is developed and included as a variable to explore how perceptions of control, or lack thereof, impact consumption behavior and resulting estimates of price elasticity. A multivariate regression model demonstrates the significance of a water insecurity variable for data sets encompassing disparate water access. When accounting for insecurity, the R-squaed value improves and the marginal price a household is willing to pay becomes a significant predictor for the household quantity consumption. The model denotes that, with all other variables held equal, a household will buy more water when the users are more water insecure. Though the reasons behind this trend require further study, the findings suggest broad policy implications by demonstrating that water distribution practices in scarcity conditions can promote consumer welfare and efficient water use.

Galaitsis, S. E.; Huber-lee, A. T.; Vogel, R. M.; Naumova, E.

2013-12-01

9

Optimal sizing of rain water tanks for domestic water conservation  

NASA Astrophysics Data System (ADS)

SummaryMelbourne is facing a severe drought having its 12th consecutive below average rainfall year. Water authorities have been forced to impose rigorous water restrictions including voluntary per capita water use targets after more than 20 years of unrestricted water supply. The current severe drought and dwindling water resources have accelerated the use of alternative water sources including domestic rainwater. There is a large variation in average annual rainfall in the Greater Melbourne area ranging from 1050 mm in the east to 450 mm in the west. Hence, there is a significant difference in the tank size required in the west and the east of Melbourne to meet a similar demand and to provide the same supply reliability. The paper presents a novel methodology and a relationship for optimal sizing of rainwater tanks considering the annual rainfall at the geographic location, the demand for rainwater, the roof area (catchment area) and the desired supply reliability. The characteristic of the developed dimensionless curve reflects these variables and paves the way for developing a web based interactive tool for selecting the optimum rainwater tank size.

Khastagir, Anirban; Jayasuriya, Niranjali

2010-02-01

10

Exergy analysis of domestic-scale solar water heaters  

Microsoft Academic Search

Solar water heater is the most popular means of solar energy utilization because of technological feasibility and economic attraction compared with other kinds of solar energy utilization. Earlier assessments of domestic-scale solar water heaters were based on the first thermodynamic law. However, this kind of assessment cannot perfectly describe the performance of solar water heaters, since the essence of energy

Wang Xiaowu; Hua Ben

2005-01-01

11

Domestic applications for aerospace waste and water management technologies  

NASA Technical Reports Server (NTRS)

Some of the aerospace developments in solid waste disposal and water purification, which are applicable to specific domestic problems are explored. Also provided is an overview of the management techniques used in defining the need, in utilizing the available tools, and in synthesizing a solution. Specifically, several water recovery processes will be compared for domestic applicability. Examples are filtration, distillation, catalytic oxidation, reverse osmosis, and electrodialysis. Solid disposal methods will be discussed, including chemical treatment, drying, incineration, and wet oxidation. The latest developments in reducing household water requirements and some concepts for reusing water will be outlined.

Disanto, F.; Murray, R. W.

1972-01-01

12

Analysis Model for Domestic Hot Water Distribution Systems: Preprint  

SciTech Connect

A thermal model was developed to estimate the energy losses from prototypical domestic hot water (DHW) distribution systems for homes. The developed model, using the TRNSYS simulation software, allows researchers and designers to better evaluate the performance of hot water distribution systems in homes. Modeling results were compared with past experimental study results and showed good agreement.

Maguire, J.; Krarti, M.; Fang, X.

2011-11-01

13

Quality of ground water from private domestic wells  

USGS Publications Warehouse

This article highlights major findings from two USGS reports: DeSimone (2009) and DeSimone and others (2009). These reports can be accessed at http://water.usgs.gov/nawqa. This article is followed by a summary of treatment considerations and options for owners of private domestic wells, written by Cliff Treyens of the National Ground Water Association.

DeSimone, Leslie A.; Hamilton, Pixie A.; Gilliom, Robert J.

2009-01-01

14

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

15

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

16

Design package for solar domestic hot water system  

SciTech Connect

Information used to evaluate the initial design of the Elcam, Inc., Solar Domestic Hot Water System is presented. Included are such items as the system performance specification, detailed design drawings and other information. Elcam, Inc., has developed two solar heated prototype hot water systems and two heat exchangers. The hot water systems consist of the following subsystems: collector, storage, control, transport, auxiliary energy, and government-furnished Site Data Acquisition. The two systems are installed at Tempe, Arizona, and San Diego, California.

None

1980-09-01

17

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

18

"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...

19

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. PMID:15109413

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

2004-01-01

20

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

21

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 US Department of Energy Order 6430.1A-1540 (Section 4.4.2).

S. Mastilovic

2000-03-02

22

Controllers for solar domestic hot-water systems  

NASA Astrophysics Data System (ADS)

Designers and installers of solar domestic hot water systems are provided resource information. Key functional control strategy and equipment alternatives and equipment descriptions adequate for writing effective DHW controller specifications are provided. The installer is provided adequate technical background to understand the functional aspects of the controller. Specific instructions to install, checkout, and troubleshoot the controller installation are included.

1981-10-01

23

Electrochemical chlorination for purifying domestic water supplies  

E-print Network

excessively by the electrolysis of water, Graphite was replaced by platinized-titanium as an anode material. This new anode experienced no detectable deterioration during the testing period, Much higher chlorine residuals were obtained with the platinized-titanium... of platinized-titanium anodes -'1 wheze chloride concentration in the water is 50 mg 1 or greater. ACKNOWLEDGEMENTS The author wishes to express sincere appreciation to Dr. Edward A, Hiler for his guidance, comments, and suggestions throughout...

Peters, Joseph Ludwig

2012-06-07

24

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

25

A concentrating collector system for domestic hot water  

Microsoft Academic Search

An inexpensive parabolic solar collector system for heating domestic hot water produces about 60 gal of 110-120°F water most of the year and 30-40 gal in mid-winter. The collector, having an effective trough area of 55 ft², was constructed from a ribbed, waterproof plywood frame covered with black painted cold rolled sheet metal and an aluminized acrylic film as a

Stromberg

1979-01-01

26

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

27

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

2013-12-01

28

Estimated Domestic, Irrigation, and Industrial Water Use in Washington, 2000  

USGS Publications Warehouse

Since 1950, the U.S. Geological Survey has published a series of Circulars and other reports on the estimated use of water in the United States at 5-year intervals. This report presents State, regional, and county estimates of the amount of water used for domestic, irrigation, and industrial purposes in the State of Washington during the year 2000. Domestic water use was estimated to be 674 million gallons per day and the per-capita rate, 114 gallons per day. Crop-irrigation water use was estimated to be 3,005 million gallons per day and the application rate, 2.2 acre-feet per acre per year, or feet per year. Golf-course irrigation water use was estimated to be 23.6 million gallons per day and the application rate, 1.4 feet per year. Industrial water use was estimated to be 681 million gallons per day. Historically, these core categories account for about 92 percent of the estimated offstream water used in Washington.

Lane, R.C.

2004-01-01

29

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

30

Domestic water conservation practices in Tlemcen City (Algeria)  

NASA Astrophysics Data System (ADS)

During the last three decades, citizens of an Algerian city are concerned with the problem of drinking water supply. Time discontinuation service became the rule. The central idea of the analysis based on interviews is to assess the role of water in the organization of the relationship between habitat and users. The fundamental question is how users, in particular women, incorporate water in their daily lives due to rationing. Having to deal with the discontinuous and frequent weak water supply, the inhabitants of the city of Tlemcen who are connected to the water supply system, as well as those connected to the water system of all Algerian towns, have developed an internal water storage system to sort out this problem. The imposed rationing has proved to be expensive for consumers. The water shortage pushed the consumers to invest in relatively expensive storage and pumping facilities to satisfy their domestic needs. As the frequency of the water supply is on a two times per week basis, the survey reveals a discrepancy in terms of volumes consumed and stored by each household. The use of water depends on the individual storage facility and the frequency of the supply. The life of the households, particularly that of the housewives, depends on the availability of water and thus on the schedules of the Company of Production of Water "Algerian Des Eaux'' (ADE). This is particularly the case when they are supplied during the night.

Habi, Mohammed; Harrouz, Omar

2014-03-01

31

Commissioning the Domestic Hot Water System on a Large University Campus: A Case Study  

E-print Network

distance of several miles from either). It is aerated to cool and remove dissolved gases at the TAMU Wellfield water treatment facility. Water is then chlorinated and pumped approximately 7 miles to campus. DHW is made in the central utilities plant... strategies for domestic hot water recirculation systems?. ASHRAE Transactions, v 105, pt 1, 1999, p 1030-1048. Killmeier, E., F., 1998. ?Domestic hot water balancing?. TAB Journal, Winter, 1998, p 4-6. Penny, D., S., 1990. ?Balancing domestic recirculated...

Chen, H.; Bensouda, N.; Claridge, D.; Bruner, H.

2004-01-01

32

Residential conservation demonstration: domestic hot water. Final report  

SciTech Connect

Four types of domestic hot water (DHW) systems installed in 80 homes throughout Florida were monitored from July 1982 to June 1983 by the Florida Solar Energy Center (FSEC) under a demonstration program for the Florida Public Service Commission. DHW systems selected for the program are located in four major population areas of Florida: Jacksonville, Orlando/Brevard County, Broward/Palm Beach Counties, and the Tampa Bay region. Twenty systems of each DHW type - conventional electric water heaters, heat pump water heaters, solar hot water systems, and waste heat recovery units - are metered to determine electricity use and hot water energy production. A microprocessor-based load profile recorder collects 15-minute interval data at each site and transfers it to an FSEC microcomputer over the telephone network twice a week. Analysis of a year's worth of data indicates that solar water heating systems operated with the highest average system efficiency and had the lowest average daily electrical load profile. Solar systems and waste heat recovery units had the least electrical demand on the Florida utility system summer peak day while solar and heat pump water heaters demonstrated the ability to shift or reduce the winter peak. Heat pump water heaters also demonstrated the best annual load factor but indicated problems with system reliability.

Merrigan, T.

1983-09-01

33

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 ...

34

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

PubMed Central

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.

2013-01-01

35

Endosymbionts of Acanthamoeba isolated from domestic tap water in Korea.  

PubMed

In a previous study, we reported our discovery of Acanthamoeba contamination in domestic tap water; in that study, we determined that some Acanthamoeba strains harbor endosymbiotic bacteria, via our molecular characterization by mitochondrial DNA restriction fragment length polymorphism (Mt DNA RFLP). Five (29.4%) among 17 Acanthamoeba isolates contained endosymbionts in their cytoplasm, as demonstrated via orcein staining. In order to estimate their pathogenicity, we conducted a genetic characterization of the endosymbionts in Acanthamoeba isolated from domestic tap water via 16S rDNA sequencing. The endosymbionts of Acanthamoeba sp. KA/WP3 and KA/WP4 evidenced the highest level of similarity, at 97% of the recently published 16S rDNA sequence of the bacterium, Candidatus Amoebophilus asiaticus. The endosymbionts of Acanthamoeba sp. KA/WP8 and KA/WP12 shared a 97% sequence similarity with each other, and were also highly similar to Candidatus Odyssella thessalonicensis, a member of the alpha-proteobacteria. The endosymbiont of Acanthamoeba sp. KA/WP9 exhibits a high degree of similarity (85-95%) with genus Methylophilus, which is not yet known to harbor any endosymbionts. This is the first report, to the best of our knowledge, to show that Methylophilus spp. can live in the cytoplasm of Acanthamoeba. PMID:19967080

Choi, Seon Hee; Cho, Min Kyoung; Ahn, Soon Cheol; Lee, Ji Eun; Lee, Jong Soo; Kim, Dong-Hee; Xuan, Ying-Hua; Hong, Yeon Chul; Kong, Hyun Hee; Chung, Dong Il; Yu, Hak Sun

2009-12-01

36

Endosymbionts of Acanthamoeba Isolated from Domestic Tap Water in Korea  

PubMed Central

In a previous study, we reported our discovery of Acanthamoeba contamination in domestic tap water; in that study, we determined that some Acanthamoeba strains harbor endosymbiotic bacteria, via our molecular characterization by mitochondrial DNA restriction fragment length polymorphism (Mt DNA RFLP). Five (29.4%) among 17 Acanthamoeba isolates contained endosymbionts in their cytoplasm, as demonstrated via orcein staining. In order to estimate their pathogenicity, we conducted a genetic characterization of the endosymbionts in Acanthamoeba isolated from domestic tap water via 16S rDNA sequencing. The endosymbionts of Acanthamoeba sp. KA/WP3 and KA/WP4 evidenced the highest level of similarity, at 97% of the recently published 16S rDNA sequence of the bacterium, Candidatus Amoebophilus asiaticus. The endosymbionts of Acanthamoeba sp. KA/WP8 and KA/WP12 shared a 97% sequence similarity with each other, and were also highly similar to Candidatus Odyssella thessalonicensis, a member of the ?-proteobacteria. The endosymbiont of Acanthamoeba sp. KA/WP9 exhibits a high degree of similarity (85-95%) with genus Methylophilus, which is not yet known to harbor any endosymbionts. This is the first report, to the best of our knowledge, to show that Methylophilus spp. can live in the cytoplasm of Acanthamoeba. PMID:19967080

Choi, Seon Hee; Cho, Min Kyoung; Ahn, Soon Cheol; Lee, Ji Eun; Lee, Jong Soo; Kim, Dong-Hee; Xuan, Ying-Hua; Hong, Yeon Chul; Kong, Hyun Hee; Chung, Dong Il

2009-01-01

37

Occurrence of polychlorinated diphenyl sulfides (PCDPSs) in surface sediments and surface water from the Nanjing section of the Yangtze River.  

PubMed

Polychlorinated diphenyl sulfides (PCDPSs) are dioxin-like compounds that could induce various adverse effects to organisms. However, little is known about the occurrence of PCDPSs in the riverine environment. In the present study, the concentrations of twenty-one types of PCDPSs in the surface sediments and in surface water from the Nanjing section of the Yangtze River were examined. A total of 19 types of PCDPSs were detected and ?PCDPSs concentrations in surface sediment and surface water ranged from 0.10 to 6.90 ng/g and 0.18 to 2.03 ng/L, respectively. The 2,2',4,4',5-penta-CDPS was the dominant congener in sediment (19.9%) and 2,2',3,3'-tetra-CDPS was the most abundant congener in water (12.2%). The tetra-CDPSs were the dominant congeners both in sediment and in water. Compared with sediment, the percentage of lower chlorinated PCDPSs in water increased distinctly. Source analysis revealed that the PCDPSs in the sediment and in the water mainly came from chemical wastewater rather than domestic sewage. There was a significant linear correlation between ?PCDPS concentrations and sediment TOC contents, while no linear correlation existed between ?PCDPS concentrations and water DOC contents. This study demonstrated the prevalent contamination by PCDPSs in sediments and in water from the Nanjing section of the Yangtze River. PMID:25168171

Zhang, Xuesheng; Qin, Li; Qu, Ruijuan; Feng, Mingbao; Wei, Zhongbo; Wang, Liansheng; Wang, Zunyao

2014-10-01

38

TRACER STUDY OF SEDIMENT-WATER INTERACTIONS IN ESTUARIES  

EPA Science Inventory

Rates of sediment bioturbation and advective exchange of water across the sediment-water interface in Narragansett Bay, Rhode Island were studied by radioactive tracer experiments. The 'biological pumping rate' of water across the interface (.7 + or - .3 cc/sq cm day) was calcula...

39

Description of 2005-10 domestic water use for selected U.S. cities and guidance for estimating domestic water use  

USGS Publications Warehouse

Domestic water-use and related socioeconomic and climatic data for 2005-10 were used in an analysis of 21 selected U.S. cities to describe recent domestic per capita water use, investigate variables that potentially affect domestic water use, and provide guidance for estimating domestic water use. Domestic water use may be affected by a combination of several factors. Domestic per capita water use for the selected cities ranged from a median annual average of 43 to 177 gallons per capita per day (gpcd). In terms of year-to-year variability in domestic per capita water use for the selected cities, the difference from the median ranged from ± 7 to ± 26 percent with an overall median variability of ± 14 percent. As a percentage of total annual water use, median annual domestic water use for the selected cities ranged from 33 to 71 percent with an overall median of 57 percent. Monthly production and water sales data were used to calculate daily per capita water use rates for the lowest 3 consecutive months (low-3) and the highest 3 consecutive months (high-3) of usage. Median low-3 domestic per capita water use for 16 selected cities ranged from 40 to 100 gpcd. Median high-3 domestic per capita water use for 16 selected cities ranged from 53 to 316 gpcd. In general, the median domestic water use as a percentage of the median total water use for 16 selected cities was similar for the low-3 and high-3 periods. Statistical analyses of combined data for the selected cities indicated that none of the socioeconomic variables, including cost of water, were potentially useful as determinants of domestic water use at the national level. However, specific socioeconomic variables may be useful for the estimation of domestic water use at the State or local level. Different socioeconomic variables may be useful in different States. Statistical analyses indicated that specific climatic variables may be useful for the estimation of domestic water use for some, but not all, of the selected cities. National average public supply per capita water use declined from 185 gpcd in 1990 to 171 gpcd in 2005. National average domestic delivery per capita water use declined from 105 gpcd in 1990 to 99 gpcd in 2005. Average State domestic delivery per capita water use ranged from 51 to 189 gpcd in 2005. The average annual total per capita water use in 19 selected cities that provided data for each year declined from 167 gpcd in 2006 to 145 gpcd in 2010. During this time period, average per capita water use measured during the low-3 period each year declined from 115 to 102 gpcd, and average per capita use measured during the high-3 period declined from 250 to 211 gpcd. Continued collection of data on water deliveries to domestic populations, as well as updated estimates of the population served by these deliveries, is recommended for determination of regional and temporal trends in domestic per capita water use. Declines in various measures of per capita water use have been observed in recent years for several States with municipal water use data-collection programs. Domestic self-supplied water use historically has not been metered. Estimates of self-supplied domestic water use are made using estimates of the population that is not served by public water suppliers and per capita coefficients. For 2005, the average State domestic self-supplied per capita use in the United States ranged from 50 to 206 gpcd. The median domestic self-supplied per capita use was 76 gpcd for States in which standard coefficients were used, and 98 gpcd for States in which coefficients were based on domestic deliveries from public supply. In specific areas with scarce resources or increasing numbers of households with private wells, an assessment of domestic water use may require metering of households or development of more specific per capita coefficients to estimate water demand.

Kenny, Joan F.; Juracek, Kyle E.

2012-01-01

40

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

41

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

42

The Suburbanization of Water Scarcity in the Barcelona Metropolitan Region: Sociodemographic and Urban Changes Influencing Domestic Water Consumption  

Microsoft Academic Search

The metropolitan region of Barcelona is facing change in urban development patterns, sociodemographic structures, and domestic water use and management. In recent years, several drought alerts have been enacted and water restrictions applied, uncovering the fragile equilibrium between the demand and the supply of this resource. We find the literature on determinants of domestic water consumption to be strongly biased

Hug March; David Saurí

2010-01-01

43

Evaluation of a multifiltration water reclamation subsystem to reclaim domestic clothes wash water  

NASA Technical Reports Server (NTRS)

An evaluation has been performed of a multifiltration water reclamation subsystem to determine its capability to recover water from domestic clothes wash water. A total of 32.89 kg (72.5 lb) of clothes were washed during eight wash cycles which used 1.4 lb of detergent, 145 gallons of hot water and 133.9 gallons of cold water. Water recovered at a weighted average process rate of 3.81 gallons per hour met the majority of the 23 requirements established for potable water by the U.S. Public Health Service. Average power consumed during this evaluation was approximately 71 watt-hours per gallon of water recovered. Filter replacement, which was required primarily for the control of micro-organisms in the recovered water averaged 4.86 filters per 100 gallons of wash water processed. The subsystem removed approximately 98 percent and virtually 100 percent of the phosphates and surfactants, respectively, from the wash water.

Hall, J. B., Jr.

1973-01-01

44

Degradation of chlorothalonil in irradiated water/sediment systems.  

PubMed

Water/sediment systems were used to investigate partitioning behavior between waters and sediments, as well as the degradation of the fungicide chlorothalonil (CHT) in each matrix. Experiments were run in the light and dark simultaneously for 30 days in both creek and pond sediment systems. Of the total applied CHT, 87-88% dissipated from the water phase in both water/sediment systems within 1 day when irradiated by simulated sunlight. In contrast, 60-68% remained in the water at day 1 in the dark. Approximately 3-6 and 10-16% of the applied CHT was found in sediments under light conditions at day 1 and in the dark at day 3, respectively which are the highest amounts observed during the experimental period. CHT similarly behaved in irradiated water/sediments and sediment-free aqueous solutions, indicating that CHT primarily degraded by photodegradation rather than adsorption to sediment in the early stages of the experiment. 4-Hydroxychlorothalonil was detected only in water in the dark systems. Trichloro-1,3-dicyanobenzene and 3-cyano-2,4,5,6-tetrachlorobenzamide were also detected and identified with liquid chromatography-electrospray ionization-mass spectrometry. These results suggest that photodegradation is likely to be important to the dissipation of CHT in aqueous solutions and microbial degradation plays an important role for residues that would ultimately reside in sediment. PMID:19127740

Kwon, Jeong-Wook; Armbrust, Kevin L

2006-05-17

45

Numerical Simulation of a Solar Domestic Hot Water System  

NASA Astrophysics Data System (ADS)

An innovative transient numerical model is presented for the simulation of a solar Domestic Hot Water (DHW) system. The solar collectors have been simulated by using a zerodimensional analytical model. The temperature distributions in the heat transfer fluid and in the water inside the tank have been evaluated by one-dimensional models. The reversion elimination algorithm has been used to include the effects of natural convection among the water layers at different heights in the tank on the thermal stratification. A finite difference implicit scheme has been implemented to solve the energy conservation equation in the coil heat exchanger, and the energy conservation equation in the tank has been solved by using the finite difference Euler implicit scheme. Energy conservation equations for the solar DHW components models have been coupled by means of a home-made implicit algorithm. Results of the simulation performed using as input data the experimental values of the ambient temperature and the solar irradiance in a summer day are presented and discussed.

Mongibello, L.; Bianco, N.; Di Somma, M.; Graditi, G.; Naso, V.

2014-11-01

46

Review of pre-treated peat applied in treating domestic wastewaters and oily waters  

E-print Network

Review of pre-treated peat applied in treating domestic wastewaters and oily waters Xiao Jiang knowledge on the application of peat in removing contaminants from domestic wastewater, oil contaminated, some general approaches in removing oil and other impurities from wastewaters and contaminated waters

Coles, Cynthia

47

Domestic wash-water reclamation using an aerospace-developed water recovery subsystem  

NASA Technical Reports Server (NTRS)

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 average process rate of 0.0146 cu m per day (3.85 gallons per day). The subsystem produced water that met all United States Public Health Standards for drinking water with the exception of two standards which could not be analyzed at the required sensitivity levels. Average energy consumption for this evaluation to maintain both the recovery process and microbial control in the recovered water was approximately 3366 kilowatt-hours per cubic meter (12.74 kilowatt-hours per gallon) of water recovered. This condition represents a worst case energy consumption since no attempt was made to recover heat energy in the subsystem. An ultraviolet radiation cell installed in the effluent line of the subsystem was effective in controlling coliform micro-organisms within acceptable levels for drinking water. The subsystem recovered virtually 100 percent of the available water in the waste-water process. In addition, the subsystem removed 99.6 percent and 98.3 percent of the surfactants and phosphate, respectively, from the wash water.

Hall, J. B., Jr.

1973-01-01

48

DEVELOPING WATER QUALITY CRITERIA FOR SUSPENDED AND BEDDED SEDIMENTS  

EPA Science Inventory

The U.S. EPA?s Framework for Developing Suspended and Bedded Sediments (SABS) Water Quality Criteria (SABS Framework) is a nationally-consistent process for developing ambient sediment quality criteria for surface waters. The SABS Framework accommodates natural variation among wa...

49

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

50

Development of hybrid electrodialysis-reverse osmosis domestic desalination unit for high recovery of product water  

Microsoft Academic Search

Reverse osmosis (RO) membrane-based domestic water desalination\\/purification units have gained wide acceptance even in India. Unfortunately, the recovery of product water from these units varies between 10 and 20% depending on total dissolved solid (TDS) of the feed water. Problem of tap water salinity is increasing, because of ground water depletion. Also, low recovery of product water during desalination is

Sreekumaran Thampy; Girish R. Desale; Vinod K. Shahi; Babubhai S. Makwana; Pushpito K. Ghosh

2011-01-01

51

Expert Meeting Report: Recommendations for Applying Water Heaters in Combination Space and Domestic Water Heating Systems  

SciTech Connect

The topic of this meeting was 'Recommendations For Applying Water Heaters In Combination Space And Domestic Water Heating Systems.' Presentations and discussions centered on the design, performance, and maintenance of these combination systems, with the goal of developing foundational information toward the development of a Building America Measure Guideline on this topic. The meeting was held at the Westford Regency Hotel, in Westford, Massachusetts on 7/31/2011.

Rudd, A.; Ueno, K.; Bergey, D.; Osser, R.

2012-07-01

52

Influence of wave and current flow on sediment-carrying capacity and sediment flux at the water-sediment interface.  

PubMed

In nearshore waters, spatial and temporal scales of waves, tidal currents, and circulation patterns vary greatly. It is, therefore, difficult to combine these factors' effects when trying to predict sediment transport processes. This paper proposes the concept of significant wave velocity, which combines the effects of waves, tides, and ocean currents using the horizontal kinetic energy superposition principle. Through a comparison of the relationship between shear stress at the water-sediment interface and sediment-carrying capacity, assuming equilibrium sediment flux, a new formula for sediment-carrying capacity, which incorporates the concept of significant wave velocities, is derived. Sediment-carrying capacity is a function of the critical velocity, which increases with water depth and decreases with increasing relative roughness of the sea bed. Finally, data from field observation stations and simulations are used to test the proposed formula. The results show that the new formula is in good agreement with both field and simulation data. This new formula for sediment-carrying capacity can be used to simulate nearshore sediment transport. PMID:25259499

Zheng, Jun; Li, Ruijie; Yu, Yonghai; Suo, Anning

2014-01-01

53

Cold-Climate Solar Domestic Hot Water Systems Analysis  

SciTech Connect

The Solar Heating and Lighting Sub-program has set the key goal to reduce the cost of saved energy [Csav, defined as (total cost, $)/(total discounted savings, kWh_thermal)] for solar domestic water heaters (SDWH) by at least 50%. To determine if this goal is attainable and prioritize R&D for cold-climate SDWH, life-cycle analyses were done with hypothetical lower-cost components in glycol, drainback, and thermosiphon systems. Balance-of-system (BOS, everything but the collector) measures included replacing metal components with polymeric versions and system simplification. With all BOS measures in place, Csav could be reduced more than 50% with a low-cost, selectively-coated, glazed polymeric collector, and slightly less than 50% with either a conventional selective metal-glass or a non-selective glazed polymer collector. The largest percent reduction in Csav comes from replacing conventional pressurized solar storage tanks and metal heat exchangers with un-pressurized polymer tanks with immersed polymer heat exchangers, which could be developed with relatively low-risk R&D.

Burch, J.; Salasovich, J.; Hillman, T.

2005-11-01

54

Solar Domestic Hot Water System manual for Day's Inn, Garland, Texas  

NASA Technical Reports Server (NTRS)

The Solar Domestic Hot Water System installed at Day's Inn, I-30 and 6222 Beltline, Garland, Texas, is described. The system is a solar collector array used to provide from 39.9 percent in December, to 84.7 percent in August, of the domestic hot water usage of the Day's Inn in Garland, Texas. The system is an automatic draindown design employing an atmospheric vented storage tank for storing the hot water collected by the 998 sq. ft. collector array.

1981-01-01

55

Subcritical water extraction of polychlorinated biphenyls from soil and sediment  

Microsoft Academic Search

Two certified reference materials, an industrial soil (CRM 481) and a river sediment (NIST 1939), were extracted by subcritical water at 50 atm and temperatures ranging from 50 to 300°C. The extraction efficiency of PCBs is extremely dependent on water temperature, since the polarity (dielectric constant) of water can be dramatically lowered by raising the water temperature. While only traces

Yu. Yang; S. Bewadt; Steven B. Hawthorne; David J. Miller

1995-01-01

56

Domestic wash water reclamation for reuse as commode water supply using filtration: Reverse-osmosis separation technique  

NASA Technical Reports Server (NTRS)

A combined filtration-reverse-osmosis water recovery system has been evaluated to determine its capability to reclaim domestic wash water for reuse as a commode water supply. The system produced water that met all chemical and physical requirements established by the U.S. Public Health Service for drinking water with the exception of carbon chloroform extractables, methylene blue active substances, and phenols. It is thought that this water is of sufficient quality to be reused as commode supply water. The feasibility of using a combined filtration and reverse-osmosis technique for reclaiming domestic wash water has been established. The use of such a technique for wash-water recovery will require a maintenance filter to remove solid materials including those less than 1 micron in size from the wash water. The reverse-osmosis module, if sufficiently protected from plugging, is an attractive low-energy technique for removing contaminants from domestic wash water.

Hall, J. B., Jr.; Batten, C. E.; Wilkins, J. R.

1974-01-01

57

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

2013-11-01

58

The effects of the water management framework and the role of domestic consumers on urban water conservation in Botswana  

Microsoft Academic Search

This article examines the adverse effects of a fragmented water management framework and the role of domestic water users on water conservation in Gaborone, the rapidly growing capital city of Botswana. There was a major drought in Botswana in 2004, which recurred in 2007. The drought seriously affected water availability in Gaborone, re-igniting the water conservation debate. Most urban households

Elisha N. Toteng

2008-01-01

59

Flow of water and sediments through Southwestern riparian systems  

E-print Network

Flow of water and sediments through Southwestern riparian systems Leonard F. Peter F. and Kenneth N. Abstract.-The paper describes streamflow, sediment movement and veg- etation interactions within riparian systems of the southwestern United States. Riparian systems are found in a wide range of vegetation types

60

Sediment resuspension mechanisms associated with internal waves in coastal waters  

Microsoft Academic Search

Large-amplitude, vertically trapped internal waves can induce sizable velocities and trigger hydrodynamic instabilities in the bottom boundary layer, thereby contributing to the resuspension of sediments and the maintenance of sediment concentration in the water column. We discuss numerical simulations of several different situations in which the boundary layer in the wave footprint undergoes hydrodynamic instability, with a resultant increase in

M. Stastna; K. G. Lamb

2008-01-01

61

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

2011-04-01

62

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

USGS Publications Warehouse

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.

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

2011-01-01

63

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

64

Water and Sediment Quality in the Yukon River Basin, Alaska, During Water Year 2001  

E-print Network

Water and Sediment Quality in the Yukon River Basin, Alaska, During Water Year 2001 Open of the Interior U.S. Geological Survey #12;Cover photo--Yukon River, looking north near Grayling, Alaska. Photo by Paul F. Schuster, 2003. #12;WATER AND SEDIMENT QUALITY IN THE YUKON RIVER BASIN, ALASKA, DURING WATER

65

Water and Sediment Quality in the Yukon River Basin, Alaska, During Water Year 2004  

E-print Network

Water and Sediment Quality in the Yukon River Basin, Alaska, During Water Year 2004 Open.S. Geological Survey scientist collecting a water-quality sample from under the ice of the Yukon River near the Dalton Highway Bridge in central Alaska #12;Water and Sediment Quality in the Yukon River Basin, Alaska

66

Water and Sediment Quality in the Yukon River Basin, Alaska, During Water Year 2002  

E-print Network

Water and Sediment Quality in the Yukon River Basin, Alaska, During Water Year 2002 Open at Eagle, Alaska. #12;Water and Sediment Quality in the Yukon River Basin, Alaska, During Water Year 2002-File Report 2005-1199 U.S. Department of the Interior U.S. Geological Survey #12;Cover photograph: Yukon River

67

Toxicity and genotoxicity of water and sediment from streams on dotted duckweed (Landoltia punctata).  

PubMed

Most rivers are used as a source to supply entire cities; the quality of water is directly related to the quality of tributaries. Unfortunately men have neglected the importance of streams, which receive domestic and industrial effluents and transport nutrients and pesticides from rural areas. Given the complexity of the mixtures discharged into these water bodies, this study aimed to evaluate the quality of water and sediment of ten tributaries of Pirapó River, in Maringá, Paraná State, Brazil. To this end, the free-floating macrophyte Landoltia punctata (G. Meyer) Les & D.J.Crawford was used as test organism in microcosm, and the toxicity of water and sediment samples was evaluated by the relative growth rate, dry/fresh biomass ratio, and genotoxic effects (comet assay). Samples of water and sediment of each stream were arranged in microcosms with L. punctata. Seven days later, plants were collected for analysis. Nutrient levels were higher than the reference location, indicating eutrophication, but the results indicated a toxic effect for only three streams, and a genotoxic effect for all streams. PMID:25627585

Factori, R; Leles, Sm; Novakowski, Gc; Rocha, Clsc; Thomaz, Sm

2014-11-01

68

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

69

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

E-print Network

Water and Sediment Quality in the Yukon River Basin, Alaska, During Water Year 2003 Open at Eagle, Alaska, just after ice breakup. #12;Water and Sediment Quality in the Yukon River Basin, Alaska-File Report 2005-1397 U.S. Department of the Interior U.S. Geological Survey #12;Cover photograph: Yukon River

70

Effects of a nearshore wastewater discharge: Water column and sediment pore water toxicity  

SciTech Connect

The relationship between water column and sediment pore water toxicity was investigated near a municipal-industrial wastewater discharge in southern Texas. Toxicity associated with effluent distributions in the water column are known to vary in both time and space. Toxicity of sediment, however, is often more stable over time. Sediment can serve as a long-term integrator of toxicity in areas subject to chronic exposure of effluents. This study addressed the relationship between water column toxicity and that found in the sediments on both spatial and temporal scales. Four 2 Km transacts were established around a nearshore wastewater outfall. Eight stations along each transact were sampled for both surface waters and sediment pore water toxicity. Toxicity was determined using a modified sea urchin fertilization test. Surface waters were sampled and tested for eight consecutive months, while sediment pore waters were sampled on three occasions over the length of this study. Results have shown that toxicity in receiving waters was a good indicator to trace movements of the highly variable effluent plume. The distribution of effluent in the water column, and hence water column toxicity, was primarily driven by local wind conditions. Toxicity in sediment porewater was, much less variable and more evenly distributed over the study site. Sediment pore water toxicity was also a good predictor of the distribution of benthic infaunal invertebrates over much of the study site.

Krause, P.R. [MEC Analytical Systems, Inc., Tiburon, CA (United States); Carr, R.S. [National Biological Survey, Corpus Christi, TX (United States)

1995-12-31

71

INSTALLATION CERTIFICATE CF-6R-MECH-01 Domestic Hot Water (DHW) (Page 1 of 2)  

E-print Network

INSTALLATION CERTIFICATE CF-6R-MECH-01 Domestic Hot Water (DHW) (Page 1 of 2) Site Address: Enforcement Agency: Permit Number: 2008 Residential Compliance Forms August 2009 1. WATER HEATING SYSTEMS,000 Btu/hr), electric resistance and heat pump water heaters, list Energy Factor (EF). For large gas

72

Water recovery and solid waste processing for aerospace and domestic applications  

NASA Technical Reports Server (NTRS)

The work is described accomplished in compiling information needed to establish the current water supply and waste water processing requirements for dwellings, and for developing a preliminary design for a waste water to potable water management system. Data generated was used in formulation of design criteria for the preliminary design of the waste water to potable water recycling system. The system as defined was sized for a group of 500 dwelling units. Study tasks summarized include: water consumption, nature of domestic water, consumer appliances for low water consumption, water quality monitoring, baseline concept, and current and projected costs.

Murawczyk, C.

1973-01-01

73

Estimate of self-supplied domestic water use in Oklahoma during 1980  

USGS Publications Warehouse

Reported or measured water-use data for the domestic self-supplied user were not available for Oklahoma; therefore estimates of water use within this classification were derived. The total self-supplied population in Oklahoma during 1980 was estimated to be 343,615, which was 11.4 percent of the total 1980 State population. The rate of water use by this group was estimated to be 56 gallons per capita per day. The estimated annual domestic self-supplied water use by county ranged from 10 to 1,180 acre-feet, with a total statewide use of 21,610 acre-feet.

Stoner, J.D.

1984-01-01

74

Methane Efflux from Lake Sediments Through Water Lilies  

Microsoft Academic Search

During winter, when water lilies have no surface leaves, the gases in the rhizome lacunae approach equilibrium with the gases of the sediment water. The resulting increase of internal pressure is manifested by the sustained streams of bubbles (up to 37 percent methane and 6 percent carbon dioxide) that escape when emerging leaves are torn in the spring. Methane continues

J. W. H. Dacey; M. J. Klug

1979-01-01

75

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

76

Measure Guideline: Combination Forced-Air Space and Tankless Domestic Hot Water Heating Systems  

SciTech Connect

This document describes design and application guidance for combination space and tankless domestic hot water heating systems (combination systems) used in residential buildings, based on field evaluation, testing, and industry meetings conducted by Building Science Corporation. As residential building enclosure improvements continue to drive heating loads down, using the same water heating equipment for both space heating and domestic water heating becomes attractive from an initial cost and space-saving perspective. This topic is applicable to single- and multi-family residential buildings, both new and retrofitted.

Rudd, A.

2012-08-01

77

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

78

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...

79

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

80

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. PMID:17181862

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

2006-01-01

81

Analysis of mitochondrial D-loop region casts new light on domestic water buffalo ( Bubalus bubalis) phylogeny  

Microsoft Academic Search

The phylogeny of water buffaloes (Bubalus bubalis) is still a matter of discussion, especially if the two types of domestic water buffalo (swamp and river) derived from different domestication events or if they are products of human selection. To obtain more insight, we analyzed the entire mitochondrial D-loop region of 80 water buffaloes of four different breeds, i.e., 19 swamp

Gerold Kierstein; Marcelo Vallinoto; Artur Silva; Maria Paula Schneider; Leopoldo Iannuzzi; Bertram Brenig

2004-01-01

82

Effects of sediment type and water level on biomass production of wetland plant species  

Microsoft Academic Search

We investigated how water level and different sediment types affect the growth of wetland plant species. Twelve different species were grown in drained and waterlogged sediments, which represented types normally encountered in wetlands: a mineral sediment from exposed sites, a sediment from a sheltered site rich in labile organic matter and an organic sediment with decomposing litter of Phragmites australis

John P. M. Lenssen; Frank B. J. Menting; Wim H. van der Putten; Cornelis W. P. M. Blom

1999-01-01

83

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...

84

Contaminated marine sediments: Water column and interstitial toxic effects  

SciTech Connect

The toxicity that contaminated sediments may introduce into the water column has not been measured extensively. In order to quantify this potential toxicity, the seawater overlying two uncontaminated and three contaminated marine sediments was evaluated in the laboratory with the sea urchin Arbacia punctulata fertilization test. Concentration of polychlorinated biphenyls (PCBs) and copper, as representative contaminants, were also measured. To characterize sources of toxicity, samples were chemically manipulated using reversed-phase chromatography, cation exchange, and chelation. Water column toxicity and contaminant concentrations were higher in the suspended exposures than in bedded exposures. Interstitial water toxicity and contaminant concentrations were generally greater than either bedded or suspended exposures. Chemical manipulation indicated that the observed toxicity in water column exposures was probably caused by metallic and/or nonionic organic contaminants. Conversely, manipulation of interstitial water did not result in significantly reduced toxicity, suggesting that other toxicants such as ammonia and hydrogen sulfide may be active.

Burgess, R.M.; McKinney, R.A. (Science Applications International Corp., Narragansett, RI (United States)); Schweitzer, K.A. (Chemical Waste Management, Inc., Dartmouth, MA (United States)); Phelps, D.K. (Environmental Protection Agency, Narragansett, RI (United States))

1993-01-01

85

Contaminated marine sediments: Water column and interstitial toxic effects  

SciTech Connect

The toxicity that contaminated sediments may introduce into the water column has not been measured extensively. In order to quantify this potential toxicity, the seawater overlying two uncontaminated and three contaminated marine sediments was evaluated in the laboratory with the sea urchin Arbacia punctulata fertilization test. Concentrations of polychlorinated biphenyls (PCBs) and copper, as representative contaminants, were also measured. To characterize sources of toxicity, samples were chemically manipulated using reversed-phase chromatography, cation exchange, and chelation. Water column toxicity and contaminant concentrations were higher in the suspended exposures than in bedded exposures. Interstitial water toxicity and contaminant concentrations were generally greater than either bedded or suspended exposures. Chemical manipulation indicated that the observed toxicity in water column exposures was probably caused by metallic and/or nonionic organic contaminants. Conversely, manipulation of interstitial waters did not result in significantly reduced toxicity, suggesting that other toxicants such as ammonia and hydrogen sulfide may be active.

Burgess, R.M.; Schweitzer, K.A.; McKinney, R.A.; Phelps, D.K.

1993-01-01

86

Solar heating and domestic hot water system installed at North Dallas High School. Final report  

SciTech Connect

This Document is the Final Technical Report of the Solar Energy System located at the North Dallas High School, Dallas, Texas. The system is designed as a retrofit in a three story with basement, concrete frame high school building. The building was air conditioned with an electric drive 300-ton chilled water central system in 1973. The building contains 126,000 square feet and the solar energy system will preheat 100 percent of domestic hot water and supply 47.5 percent of annual building heating requirements. During the building cooling seasons, the solar energy system will supply 100 percent of domestic hot water. The solar energy system consists of 4800 square feet (320 panels) Lennox/Honeywell flat plate liquid collector subsystem, and a 10,000 gallon steel tank storage subsystem circulating hot water producing 686.6 x 10/sup 6/ Btu/year (specified) building heating and domestic hot water heating. The start up date is December 4, 1979. Extracts from the site files, specification references for solar modification to existing building heating and domestic hot water systems, drawings, installation, operation and maintenance instructions are presented.

Not Available

1980-05-01

87

Procedures for Collecting and Processing Streambed Sediment and Pore Water for Analysis of Mercury as  

E-print Network

Procedures for Collecting and Processing Streambed Sediment and Pore Water for Analysis of Mercury Streambed Sediment and Pore Water for Analysis of Mercury as Part of the National Water-Quality Assessment for collecting and processing streambed sediment and pore water for analysis of mercury as part of the National

88

Water recovery and solid waste processing for aerospace and domestic applications. Volume 1: Final report  

NASA Technical Reports Server (NTRS)

A comprehensive study of advanced water recovery and solid waste processing techniques employed in both aerospace and domestic or commercial applications is reported. A systems approach was used to synthesize a prototype system design of an advanced water treatment/waste processing system. Household water use characteristics were studied and modified through the use of low water use devices and a limited amount of water reuse. This modified household system was then used as a baseline system for development of several water treatment waste processing systems employing advanced techniques. A hybrid of these systems was next developed and a preliminary design was generated to define system and hardware functions.

Murray, R. W.

1973-01-01

89

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

90

Harvesting Energy from the Marine Sediment-Water Interface  

E-print Network

Harvesting Energy from the Marine Sediment-Water Interface C L A R E E . R E I M E R S * College D E R * Center for Biomolecular Science and Engineering - Code 6900, Naval Research Laboratory, Virginia 22308 W E I W A N G Institute of Marine and Coastal Sciences, Rutgers University, New Brunswick

Rosen, I. Gary

91

Bank Erosion, Mass Wasting, Water Clarity, Bathymetry and a Sediment  

E-print Network

Bank Erosion, Mass Wasting, Water Clarity, Bathymetry and a Sediment Budget Along the Dam this report. Suggested citation: Schenk, E.R., Hupp, C.R., Richter, J.M., and Kroes, D.E. 2010, Bank erosion...........................................................................................................................................................3 Bank Erosion

92

SURVEY OF CONTAMINANTS IN FRASER RIVER SUSPENDED SEDIMENT AND WATER  

E-print Network

SURVEY OF CONTAMINANTS IN FRASER RIVER SUSPENDED SEDIMENT AND WATER UPSTREAM AND DOWNSTREAM, for their scientific and field support. We would like to thank Captain A. Domaas of the Fraser River Harbour Commission and the British Columbia Ministry of Highways for providing access to the lower Fraser River and Captain R. Taylor

93

Evaluation of genotoxicity and toxicity of water and sediment samples from a Brazilian stream influenced by tannery industries.  

PubMed

This paper reports results of genotoxicity and toxicity studies of water and sediment samples collected from the Estância Velha stream of southern Brazil, a stream transporting both domestic sewage and effluents from regional factories working in the leather industry. Three sites were selected: in the stream headwaters (Site 1), located downstream of an urban area (Site 2), and near the basin outfall (Site 3). Results obtained with Allium cepa showed no evidence of chromosomal mutation, either in water or in sediment, during winter or summer seasons, but samples collected below Site 1 showed high toxicity. Physical and chemical analyses showed high concentrations of pollutants at these sites. Ecotoxicity tests with Daphnia magna and Ceriodaphnia dubia measured toxicity in water from Sites 2 and 3 in summer 2004. A toxic effect on Hyalella azteca was only found in sediment from Site 3 during winter 2003 and summer 2004. The results suggest that the synergy among different compounds in domestic and industrial sewage discharges can make it difficult to maintain system stability. PMID:17157352

Júnior, Horst Mitteregger; Silva, Juliana da; Arenzon, Alexandre; Portela, Carina Saraiva; Ferreira, Isabel Cristina Fernandes de Sá; Henriques, João Antônio Pêgas

2007-04-01

94

Estimate of self-supplied domestic water use in Nebraska during 1980  

USGS Publications Warehouse

No data base of actual measurements exists for self-supplied, domestic water use in Nebraska, because Nebraska laws do not require drilling permits, well registration, or reporting of volumes withdrawn from domestic wells. Self-supplied, domestic water use of 31,280 acre-ft in Nebraska during 1980 was computed from estimates of gal/day/capita use for each county. This represents an average of 95 gal/day/capita. During 1980, county use volumes ranged from 30 acre-ft in Hooker and Pawnee Counties to 1,380 acre-ft in Douglas County, and Hydrologic Unit use volumes ranged from < 5 acre-ft to 2,270 acre-ft. Natural Resources Districts ' (NRD) use volumes ranged from 360 acre-ft in Middle Niobrara NRD to 3,530 acre-feet in the Lower Elkhorn NRD for the same period. (Author 's abstract)

Steele, E.K.

1985-01-01

95

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

96

Preliminary design package for Sunspot Domestic Hot Water Heating System  

NASA Technical Reports Server (NTRS)

The design review includes a drawing list, auto-control logic, measurement definitions, and other document pertaining to the solar heated prototype hot water systems and two heat exchangers. The hot water systems consist of the following subsystems: collector, storage, control transport, auxiliary energy, and site data acquisition.

1976-01-01

97

Comparison of six generic solar domestic hot water systems  

SciTech Connect

The cost effectiveness of residential solar water heating is explored by analyzing six different system types. A figure of merit (that considers both performance and cost) is calculated for each system, providing information for both researchers and industry. Thermosyphon water heaters are determined to be the most cost effective option, and their wider application is recommended once a reliable draindown technique is developed.

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

1980-04-01

98

CO 2 HEAT PUMP FOR DOMESTIC HOT WATER  

Microsoft Academic Search

This paper describes the development of a CO 2 air\\/water heat pump, designed to meet the tap hot water requirement of a residential building located in the northern part of Italy. The basic design consists of a single-stage piston compressor, a coaxial type gas cooler, an electronic expansion valve, a finned tube evaporator and a low pressure receiver. The heat

E. FORNASIERI; S. GIROTTO; S. MINETTO

99

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

100

Mercury, Methylmercury, and Other Constituents in Sediment and Water from Seasonal and Permanent  

E-print Network

Mercury, Methylmercury, and Other Constituents in Sediment and Water from Seasonal and Permanent, the Sacramento River Watershed Program, and the United States Environmental Protection Agency Mercury A., 2009, Mercury, methylmercury, and other constituents in sediment and water from seasonal

101

DOMESTIC HOT WATER PRODUCTION IN A NET ZERO ENERGY TRIPLEX IN MONTREAL  

Microsoft Academic Search

This article focuses on a system of production of domestic hot water in a net zero energy triplex located in Montréal and occupied by 6 persons. This system is assessed and optimized using TRNSYS simulations. Results indicate that it is possible to obtain a renewable fraction (similar to the well-known solar fraction) greater than unity. This is achieved by using

Daniel Picard; Michel Bernier; Roland Charneux

102

Solar heating and domestic hot water system installed at North Dallas High School  

NASA Technical Reports Server (NTRS)

The solar energy system located at the North Dallas High School, Dallas, Texas is discussed. The system is designed as a retrofit in a three story with basement, concrete frame high school building. Extracts from the site files, specification references for solar modification to existing building heating and domestic hot water systems, drawings, installation, operation and maintenance instructions are included.

1980-01-01

103

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

104

Effect of rainfall on settling velocity of sediment particles in quiescent water  

E-print Network

- ment laden water body is not known. The settling velocity of sediment particles in flowing or quiescent water affects the vertical distribution of the suspended sediment and also the amount of sediment deposition. Any effect of rainfall... on the settling velocity of sediment particles would affect the distribution of both suspended load and amount of deposition. The effect of rainfall on sediment transportation is not thoroughly understood. Very little research has been conducted in the field...

Bhuiyan, A. F. M. Sadiqul Islam

2012-06-07

105

Benthic foraminiferal microhabitat selection and sediment pore water geochemical gradients  

NASA Astrophysics Data System (ADS)

Benthic foraminiferal shell geochemistry has supplied proxies for a range of paleo-environmental variables. This geochemistry reflects the immediate microenvironment in which shell material is calcified. In many ways, the ideal, from a proxy point of view, would be that species consistently stratify themselves in the sediment column and that each records geochemical conditions from a particular depth. To evaluate the incorporation of geochemical proxies we examined habitats and geochemical conditions in marine sediments on the microscale experienced by the foraminifera. We used sites down the continental margin of the European Arctic where the only significant forcing variable was flux of organic carbon to the seabed. Multicores were maintained at in-situ conditions while we collected oxygen microprofiles, pore waters and micro-sampled for foraminifera. We used the geochemical data to define microenvironments directly where we collected foraminifera and to determine the local organic flux. We found that species abundance and distribution in the sediments was strongly influenced by the flux, as were the sedimentary geochemical gradients. However, species abundances and vertical distributions also were strongly influenced by the presence and structures of larger fauna. Foraminifera were most abundant where macrofauna were common and had bio-irrigated the sediments producing a complex mosaic of geochemical microenvironments. Species responded to this with variable distribution in the sediment profile, likely a result of seeking niches defined by chemical and biotic cues. This behavior could well explain such phenomena as the ‘Mackensen effect' in foraminiferal shell geochemistry.

Yavorska, Iryna; Loubere, Paul; Jacobsen, Brittani; Husum, Katrine

2010-05-01

106

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

107

Solar heat pump systems for domestic hot water  

Microsoft Academic Search

Vapour compression heat pumps can upgrade ambient heat sources to match the desired heating load temperature. They can offer considerable increase in operational energy efficiency compared to current water heating systems. Solar heat pumps collect energy not only from solar radiation but also from the ambient air. They can operate even at night or in totally overcast conditions. Since the

Lu Aye; W. W. S Charters; C Chaichana

2002-01-01

108

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

109

Remote Sensing of Suspended Sediments and Shallow Coastal Waters  

NASA Technical Reports Server (NTRS)

Ocean color sensors were designed mainly for remote sensing of chlorophyll concentrations over the clear open oceanic areas (case 1 water) using channels between 0.4 and 0.86 micrometers. The Moderate Resolution Imaging Spectroradiometer (MODIS) launched on the NASA Terra and Aqua Spacecrafts is equipped with narrow channels located within a wider wavelength range between 0.4 and 2.5 micrometers for a variety of remote sensing applications. The wide spectral range can provide improved capabilities for remote sensing of the more complex and turbid coastal waters (case 2 water) and for improved atmospheric corrections for Ocean scenes. In this article, we describe an empirical algorithm that uses this wide spectral range to identifying areas with suspended sediments in turbid waters and shallow waters with bottom reflections. The algorithm takes advantage of the strong water absorption at wavelengths longer than 1 micrometer that does not allow illumination of sediments in the water or a shallow ocean floor. MODIS data acquired over the east coast of China, west coast of Africa, Arabian Sea, Mississippi Delta, and west coast of Florida are used in this study.

Li, Rong-Rong; Kaufman, Yoram J.; Gao, Bo-Cai; Davis, Curtiss O.

2002-01-01

110

PII S0016-7037(99)00084-8 Dissolved sulfide distributions in the water column and sediment pore waters  

E-print Network

sites (550 and 590 m) with low ( 10 M) bottom-water dissolved-oxygen concentrations. Pore-water profilesPII S0016-7037(99)00084-8 Dissolved sulfide distributions in the water column and sediment pore) Abstract--Dissolved sulfide concentrations in the water column and in sediment pore waters were measured

van Geen, Alexander

111

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

112

A sediment resuspension and water quality model of Lake Okeechobee  

USGS Publications Warehouse

The influence of sediment resuspension on the water quality of shallow lakes is well documented. However, a search of the literature reveals no deterministic mass-balance eutrophication models that explicitly include resuspension. We modified the Lake Okeeehobee water quality model - which uses the Water Analysis Simulation Package (WASP) to simulate algal dynamics and phosphorus, nitrogen, and oxygen cycles - to include inorganic suspended solids and algorithms that: (1) define changes in depth with changes in volume; (2) compute sediment resuspension based on bottom shear stress; (3) compute partition coefficients for ammonia and ortho-phosphorus to solids; and (4) relate light attenuation to solids concentrations. The model calibration and validation were successful with the exception of dissolved inorganic nitrogen species which did not correspond well to observed data in the validation phase. This could be attributed to an inaccurate formulation of algal nitrogen preference and/or the absence of nitrogen fixation in the model. The model correctly predicted that the lake is lightlimited from resuspended solids, and algae are primarily nitrogen limited. The model simulation suggested that biological fluxes greatly exceed external loads of dissolved nutrients; and sedimentwater interactions of organic nitrogen and phosphorus far exceed external loads. A sensitivity analysis demonstrated that parameters affecting resuspension, settling, sediment nutrient and solids concentrations, mineralization, algal productivity, and algal stoichiometry are factors requiring further study to improve our understanding of the Lake Okeechobee ecosystem.

James, R.T.; Martin, J.; Wool, T.; Wang, P.-F.

1997-01-01

113

Methane efflux from lake sediments through water lilies.  

PubMed

During winter, when water lilies have no surface leaves, the gases in the rhizome lacunae approach equilibrium with the gases of the sediment water. The resulting increase of internal pressure is manifested by the sustained streams of bubbles (up to 37 percent methane and 6 percent carbon dioxide) that escape when emerging leaves are torn in the spring. Methane continues to enter the roots and rhizome during summer, rapidly moves up the petioles, and passes out through the emergent leaves into the atmosphere. PMID:17841139

Dacey, J W; Klug, M J

1979-03-23

114

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

Microsoft Academic Search

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

L. A. K. Mertes; M. O. Smith; J. B. Adams

1993-01-01

115

A novel tracer technique for the assessment of fine sediment dynamics in urban water management systems.  

PubMed

Urban storm water run off can reduce the quality of receiving waters due to high sediment load and associated sediment-bound contaminants. Consequently, urban water management systems, such as detention ponds, that both modify water quantity through storage and improve water quality through sediment retention are frequently-used best management practices. To manage such systems effectively and to improve their efficiency, there is a need to understand the dynamics (transport and settling) of sediment, and in particular the fine sediment fraction (<63 ?m) and its associated contaminants within urban storm water management systems. This can be difficult to achieve, as modelling the transport behaviour of fine-grained and cohesive sediment is problematic and field-based measurements can be costly, time-consuming and unrepresentative. The aim of this study was to test the application of a novel cohesive sediment tracer and to determine fine sediment transport dynamics within a storm water detention pond. The cohesive sediment tracer used was a holmium labelled montmorillonite clay which flocculated and had similar size and settling velocity to the natural pond sediment it was intended to mimic. The tracer demonstrated that fine sediment was deposited across the entire pond, with the presence of reed beds and water depth being important factors for maximising sediment retention. The results of the sediment tracer experiment were in good agreement with those of a mathematical sediment transport model. Here, the deposited sediment tracer was sampled by collecting and analysing surface pond sediments for holmium. However, analysis and sampling of the three dimensional suspended tracer 'cloud' may provide more accurate information regarding internal pond sediment dynamics. PMID:21420140

Spencer, K L; Droppo, I G; He, C; Grapentine, L; Exall, K

2011-04-01

116

Solar heating and domestic hot water system installed at Kansas City, Fire Stations, Kansas City, Missouri  

NASA Technical Reports Server (NTRS)

The solar system was designed to provide 47 percent of the space heating, 8,800 square feet area and 75 percent of the domestic hot water (DHW) load. The solar system consists of 2,808 square feet of Solaron, model 2001, air, flat plate collector subsystem, a concrete box storage subsystem which contains 1,428 cubic feet of 0.5 inch diameter pebbles weighing 71.5 tons, a DHW preheat tank, blowers, pumps, heat exchangers, air ducting, controls and associated plumbing. Two 120 gallon electric DHW heaters supply domestic hot water which is preheated by the solar system. Auxiliary space heating is provided by three electric heat pumps with electric resistance heaters and four 30 kilowatt electric unit heaters. There are six modes of system operation.

1980-01-01

117

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

118

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 ...

119

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...

120

Hydrogeology of the Unconsolidated Sediments, Water Quality, and Ground-Water/Surface-Water Exchanges in the Methow River Basin, Okanogan County, Washington  

USGS Publications Warehouse

The U.S. Geological Survey, in cooperation with Okanogan County, investigated the hydrogeology of the unconsolidated sedimentary deposits in the Methow River Basin, the quality of surface and ground waters, and the exchanges between ground water and surface water. Alluvium (Qa) and glaciofluvial sediments (Qga) deposited during the Quaternary period constitute the primary aquifer in the Methow River Basin, which is used as a source of water for domestic and public-water supplies and for maintaining streamflow during seasonal dry periods. The sediments form a nearly continuous unit along the valley bottom from above the Lost River to the confluence of the Methow and Columbia Rivers, covering more than 45 square miles of the basin?s surface. There are no distinct units within the deposit that can be identified across or along the valley except for fragments of a possible lake bed near the town of Twisp. Ground-water levels in the unconsolidated aquifer are highest during the summer and lowest in the winter and early spring. Ground water and surface water, sampled during June and September 2001, generally were of high quality. Only two samples from domestic and municipal wells indicated the possibility of ground-water contamination from nitrate and arsenic concentrations. In both cases, potential contamination was isolated to an individual well. No trends in water quality were apparent when comparing the results of this investigation with previous studies. The flow of water between rivers and aquifers is important for regulating the availability of water resources for in-stream and out-of-stream uses in the Methow River Basin. Ground-water discharge from the unconsolidated aquifer to the Methow River from Lost River to Pateros ranged from an estimated 153,000 acre-ft in water year 2001 to 157,000 acre-ft in water year 2002. In contrast, ground-water discharge to the lower Twisp River from Newby Creek to near Twisp ranged from 4,700 acre-ft in water year 2001 to 9,200 acre-ft in water year 2002. The Methow and Twisp Rivers, among others in the basin, are major sources of recharge for the unconsolidated aquifer, particularly during high-flow periods in May and June. Aquifer recharge by both rivers increased with streamflow in water year 2002 compared to water year 2001 as indicated by daily losses of streamflow. Aquifer recharge by the Methow River from Lost River to Pateros was estimated to be 82,000 acre-ft in water year 2001 and 137,000 acre-ft in water year 2002. Aquifer recharge by the Twisp River from Newby Creek to near Twisp was estimated to be 2,000 acre-ft in water year 2001 and 6,400 acre-ft in water year 2002. Seepage from unlined irrigation canals also recharges the unconsolidated aquifer during the late spring and summer and may contribute as much 38,000 acre-ft annually to aquifer recharge in the basin. Some portion of this ground water returns to rivers as indicated by a seasonal increase in ground-water discharge in the Methow River from Winthrop to Twisp and in the lower Twisp River during late summer and early autumn. Although the increase is likely due primarily to irrigation canal seepage, however, fluvial recharge during the summer also may have contributed to the increase. The increased rate of ground-water discharge decays by January in both reaches.

Konrad, Christopher P.; Drost, Brian W.; Wagner, Richard J.

2003-01-01

121

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...

122

River acid mine drainage: sediment and water mapping through hyperspectral Hymap data  

Microsoft Academic Search

The Odiel River (Huelva, southwest Spain) carries acidic water originating from mine waste contamination, including massive sulphide ore deposits. As the river approaches the coastal estuary, tidal factors influence both sediment and water dynamics. As water velocity decreases, sediment load transport capacity also decreases, building river bars consisting of boulders upstream and sands downstream. Salt water near the estuary affects

A. Riaza; J. Buzzi; E. García-Meléndez; V. Carrère; A. Sarmiento; A. Müller

2012-01-01

123

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

124

Predicting water quality data in an unfilled reservoir using microcosm sediment-water simulation.  

PubMed

The technique of microcosm sediment-water simulation was used to obtain predictive water quality data for the proposed Jordanelle Reservoir, Heber City, Utah. Sediment-water microcosms were prepared for four sites located in the north arm of the reservoir basin, including two sites located in an abandoned acid mine tailings pond. Data obtained from the tailings pond microcosms indicated that low pH water and high trace metal concentrations may exist in this area of the reservoir. These data suggested that the tailings material should be contained or removed prior to reservoir filling. Other sites in the reservoir basin exhibited water quality considered normal for reservoirs of similar elevation and basin geology. Near the proposed dam, anaerobic conditions could develop rapidly due to available concentrations of organic carbon, and the subsequent release of Zn, Fe, and Mn may pose a water quality problem. At the sampling site near Keetley, simulation data indicated that anaerobic conditions will not develop as quickly or be as severe as conditions expected near the dam. Overall, the availability of nitrogen and phosphorus in the Provo River and Jordanelle sediments indicated that problems with algal blooms may exist in the reservoir. Also presented is a brief discussion of the advantages and disadvantages associated with microcosm sediment-water simulation. PMID:24213801

Craft, D

1985-12-01

125

Concentrations of Elements in Sediments and Selective Fractions of Sediments, and in Natural Waters in Contact with Sediments from Lake Roosevelt, Washington, September 2004  

USGS Publications Warehouse

Twenty-eight composite and replicate sediment samples from 8 Lake Roosevelt sites were collected and analyzed for 10 alkali and alkaline earth elements, 2 non-metals, 20 metals, and 4 lanthanide and actinide elements. All elements were detected in all sediment samples except for silver (95 percent of the elements detected for 1,008 analyses), which was detected only in 4 samples. Sequential selective extraction procedures were performed on single composite samples from the eight sites. The percentage of detections for the 31 elements analyzed ranged from 76 percent for the first extraction fraction using a weak extractant to 93 percent for the four-acid dissolution of the sediments remaining after the third sequential selective extraction. Water samples in various degrees of contact with the sediment were analyzed for 10 alkali and alkaline earth elements, 5 non-metals, 25 metals, and 16 lanthanide and actinide elements. The filtered water samples included 10 samples from the reservoir water column at 8 sites, 32 samples of porewater, 55 samples from reservoir water overlying sediments in 8 cores from the site incubated in a field laboratory, and 24 water samples that were filtered after being tumbled with sediments from 8 sites. Overall, the concentrations of only 37 percent of the 6,776 analyses of the 121 water samples were greater than the reporting limit. Selenium, bismuth, chromium, niobium, silver, and zirconium were not detected in any water samples. The percentage of concentrations for the water samples that were above the reporting limit ranged from 14 percent for the lanthanide and actinide elements to 77 percent for the alkali and alkaline earth elements. Concentrations were greater than reporting limits in only 23 percent of the analyses of reservoir water and 29 percent of the analyses of reservoir water overlying incubation cores. In contrast, 47 and 48 percent of the concentrations of porewater and water samples tumbled with sediments, respectively, were greater than the reporting limit.

Paulson, Anthony J.; Wagner, Richard J.; Sanzolone, Richard F.; Cox, Steven E.

2006-01-01

126

Sediment Transport Dynamics in River Networks: A Model for Higher-Water Seasons  

Microsoft Academic Search

A dynamical model is proposed to study sediment transport in river networks in higher-water seasons. The model emphasizes\\u000a the difference between the sediment-carrying capability of the stream in higher-water seasons and that in lower-water seasons.\\u000a The dynamics of sediment transport shows some complexities such as the complex dependence of the sediment-carrying capability\\u000a on sediment concentration, the response of the channel(via

Jie Huo; Xu-Ming Wang; Rui Hao; Jin-Feng Zhang

2009-01-01

127

Physical extraction of microorganisms from water-saturated, packed sediment.  

PubMed

Microbial characterization of aquifers should include samples of both suspended and attached microorganisms (biofilms). We investigated the effect of shear, sonication, and heat on the extraction of microorganisms from water-saturated, packed sediment columns containing established biofilms. Shear was studied by increasing flow velocity of the column eluent, sonication by treating the columns with ultrasound at different power levels, and heat by warming up the column eluent to different temperatures. Effluent cell concentrations were used as a measure of extraction efficiency. Dissolved organic carbon and adenosine tri-phosphate (ATP) concentrations were used to corroborate cell-extraction results. Additionally, ATP was used as an indicator of cell-membrane integrity. Extraction quality was determined by comparing terminal-restriction fragment length polymorphism (T-RFLP) profiles of extracted bacterial communities with destructively sampled sediment-community profiles. Sonication and heat increased the extraction efficiency up to 200-fold and yielded communities comparable to the sediment community. These treatments showed high potential for in-situ application in aquifers. PMID:24961067

Ugolini, Fabio; Schroth, Martin H; Bürgmann, Helmut; Zeyer, Josef

2014-05-01

128

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

129

Assessing domestic water use habits for more effective water awareness campaigns during drought periods: a case study in Alicante, Eastern Spain  

NASA Astrophysics Data System (ADS)

The design of water awareness campaigns could benefit from knowledge on the specific characteristics of domestic water use and of the factors that may influence certain water consumption habits. This paper investigates water use in 450 households of 10 municipalities of drought prone Alicante (Spain) with the objective of increasing knowledge about existing domestic water behavior and therefore help to improve the design and implementation of future water awareness campaigns. The survey results indicate that users already follow many of the conservation practices mentioned in messages. Moreover, campaigns need to take into account the differences in water use and habits derived from differences in urban models (concentrated or disperse).

March, H.; Hernández, M.; Saurí, D.

2014-11-01

130

Investigating the influence of incomplete separation of sediment and water on experimental sorption coefficients of chlorinated benzenes  

Microsoft Academic Search

The influence of incomplete separation of water and sediment in batch sorption experiments was investigated with five chlorinated benzenes. Only the sorption coefficients of the most hydrophobic chemical, hexachlorobenzene, decreased with increasing sediment\\/water ratios. This decrease is assumed to be caused by an increasing amount of sediment that was not separated from the aqueous phase. To quantify this incomplete water\\/sediment

S. Marca Schrap; Manuela Haller; Antoon Opperhuizen

1995-01-01

131

Evaluating Domestic Hot Water Distribution System Options With Validated Analysis Models  

SciTech Connect

A developing body of work is forming that collects data on domestic hot water consumption, water use behaviors, and energy efficiency of various distribution systems. A full distribution system developed in TRNSYS has been validated using field monitoring data and then exercised in a number of climates to understand climate impact on performance. This study builds upon previous analysis modelling work to evaluate differing distribution systems and the sensitivities of water heating energy and water use efficiency to variations of climate, load, distribution type, insulation and compact plumbing practices. Overall 124 different TRNSYS models were simulated. Of the configurations evaluated, distribution losses account for 13-29% of the total water heating energy use and water use efficiency ranges from 11-22%. The base case, an uninsulated trunk and branch system sees the most improvement in energy consumption by insulating and locating the water heater central to all fixtures. Demand recirculation systems are not projected to provide significant energy savings and in some cases increase energy consumption. Water use is most efficient with demand recirculation systems, followed by the insulated trunk and branch system with a central water heater. Compact plumbing practices and insulation have the most impact on energy consumption (2-6% for insulation and 3-4% per 10 gallons of enclosed volume reduced). The results of this work are useful in informing future development of water heating best practices guides as well as more accurate (and simulation time efficient) distribution models for annual whole house simulation programs.

Weitzel, E.; Hoeschele, M.

2014-09-01

132

Mercury Species and Other Selected Constituent Concentrations in Water, Sediment, and Biota of  

E-print Network

Mercury Species and Other Selected Constituent Concentrations in Water, Sediment, and Biota Data Series 658 #12;#12;Mercury Species and Other Selected Constituent Concentrations in Water.J., 2012, Mercury species and other selected constituent concentrations in water, sediment, and biota

133

The Release of Phosphorus to Porewater and Surface Water from River Riparian Sediments  

Microsoft Academic Search

Sediments can be both a source and a sink of dissolved phosphorus (P) in surface water and shallow groundwater. Using laboratory mesocosms, we studied the infl uence of fl ooding with deionized water and simulated river water on P release to solution using sediment columns taken from a riparian wetland. Th e mesocosm incubation results showed that rather than retaining

Ben W. J. Surridge; A. L. Heathwaite; Andrew J. Baird

2007-01-01

134

Degradation, Fate and Bioavailability of Sulfamethazine in Pond Water and Sediment  

Technology Transfer Automated Retrieval System (TEKTRAN)

Antibiotics from animal agriculture are found in surface waters and stream sediments. We investigated the degradation and fate of sulfamethazine in small pond water and sediment microcosms. Sulfamethazine [14C-phenyl] was added to the water phase directly, or in a dilute swine manure solution that s...

135

A multilayer shallow water system for polydisperse sedimentation  

NASA Astrophysics Data System (ADS)

This work considers the flow of a fluid containing one disperse substance consisting of small particles that belong to different species differing in size and density. The flow is modelled by combining a multilayer shallow water approach with a polydisperse sedimentation process. This technique allows one to keep information on the vertical distribution of the solid particles in the mixture, and thereby to model the segregation of the particle species from each other, and from the fluid, taking place in the vertical direction of the gravity body force only. This polydisperse sedimentation process is described by the well-known Masliyah-Lockett-Bassoon (MLB) velocity functions. The resulting multilayer sedimentation-flow model can be written as a hyperbolic system with nonconservative products. The definitions of the nonconservative products are related to the hydrostatic pressure and to the mass and momentum hydrodynamic transfer terms between the layers. For the numerical discretization a strategy of two steps is proposed, where the first one is also divided into two parts. In the first step, instead of approximating the complete model, we approximate a reduced model with a smaller number of unknowns. Then, taking advantage of the fact that the concentrations are passive scalars in the system, we approximate the concentrations of the different species by an upwind scheme related to the numerical flux of the total concentration. In the second step, the effect of the transference terms defined in terms of the MLB model is introduced. These transfer terms are approximated by using a numerical flux function used to discretize the 1D vertical polydisperse model, see Bürger et al. [ R. Bürger, A. García, K.H. Karlsen, J.D. Towers, A family of numerical schemes for kinematic flows with discontinuous flux, J. Eng. Math. 60 (2008) 387-425]. Finally, some numerical examples are presented. Numerical results suggest that the multilayer shallow water model could be adequate in situations where the settling takes place from a suspension that undergoes horizontal movement.

Fernández-Nieto, E. D.; Koné, E. H.; Morales de Luna, T.; Bürger, R.

2013-04-01

136

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

137

Quantitative bacterial examination of domestic water supplies in the Lesotho Highlands: water quality, sanitation, and village health.  

PubMed Central

Reported are the results of an examination of domestic water supplies for microbial contamination in the Lesotho Highlands, the site of a 20-year-old hydroelectric project, as part of a regional epidemiological survey of baseline health, nutritional and environmental parameters. The population's hygiene and health behaviour were also studied. A total of 72 village water sources were classified as unimproved (n = 23), semi-improved (n = 37), or improved (n = 12). Based on the estimation of total coliforms, which is a nonspecific bacterial indicator of water quality, all unimproved and semi-improved water sources would be considered as not potable. Escherichia coli, a more precise indicator of faecal pollution, was absent (P < 0.001) in most of the improved water sources. Among 588 queried households, only 38% had access to an "improved" water supply. Sanitation was a serious problem, e.g. fewer than 5% of villagers used latrines and 18% of under-5-year-olds had suffered a recent diarrhoeal illness. The study demonstrates that protection of water sources can improve the hygienic quality of rural water supplies, where disinfection is not feasible. Our findings support the WHO recommendation that E. coli should be the principal microbial indicator for portability of untreated water. Strategies for developing safe water and sanitation systems must include public health education in hygiene and water source protection, practical methods and standards for water quality monitoring, and a resource centre for project information to facilitate programme evaluation and planning. PMID:10593031

Kravitz, J. D.; Nyaphisi, M.; Mandel, R.; Petersen, E.

1999-01-01

138

LIGHT DEPENDENCE OF SEDIMENT-WATER NUTRIENT EXCHANGE IN A GULF OF MEXICO  

EPA Science Inventory

The flux of dissolved nutrients between sediments and overlying water is an important component of nutrient processing in estuaries. These fluxes can be linked to sediment metabolism, which in shallow estuaries can be affected by light. Sediment cores were collected at sight stat...

139

Continental Shelf Research 24 (2004) 20292043 A conceptual model for river water and sediment dispersal in  

E-print Network

Continental Shelf Research 24 (2004) 2029­2043 A conceptual model for river water and sediment mouth on a peak day of river discharge revealed that sediment rapidly settled from the freshened surface in the surface plume continued at $50% per day. These observations suggest that river sediment undergoes rapid

Washburn, Libe

140

STAND, A DYNAMIC MODEL FOR SEDIMENT TRANSPORT AND WATER QUALITY. (R825758)  

EPA Science Inventory

We introduce a new model–STAND (Sediment-Transport-Associated Nutrient Dynamics)–for simulating stream flow, sediment transport, and the interactions of sediment with other attributes of water quality. In contrast to other models, STAND employs a fully dynamic ba...

141

Contribution of sediments in the removal of microcystin-LR from water.  

PubMed

Microcystins are produced by several species of cyanobacteria and can harm aquatic organisms and human beings. Sediments have the potential to contribute to the removal of dissolved microcystins from the water body through either adsorption to sediment particles or biodegradation by the sediment's bacterial community. However, the relative contribution of these two removal processes remains unclear and little is known about the significance of sediment's overall contribution. To study this, changes in the concentration of microcystin-LR (MCLR) in the presence of sediment, sediment with microbial inhibitor, and non-sterile lake water were quantified in a laboratory experiment. Our results show that, in the presence of sediment, MCLR concentration decreased significantly in an exponential way without a lag phase, with an average degradation rate of 9 ?g d(-1) in the first 24 h. This indicates that sediment can contribute to the removal of MCLR from the water immediately and effectively. Whilst both, the biodegradation and adsorption ability of the sediment contributed significantly to the removal of MCLR from the water body, biodegradation was shown to be the dominant removal process. Also, the sediment's ability to degrade MCLR from the water was shown to be faster than the biodegradation through the bacterial community in the water. The present study emphasizes the importance of sediments for the removal of microcystins from a water body. This will be especially relevant in shallow systems where the interaction between the water and the sediment is naturally high. Our results are also useful for the application of sediments to remove microcystins at water treatment facilities. PMID:24631598

Song, Haihong; Reichwaldt, Elke S; Ghadouani, Anas

2014-06-01

142

A Coupled Biogeochemical Reactive Transport Model in Bed Sediments and Water Column of Riverine Systems  

Microsoft Academic Search

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

A. Massoudieh; F. A. Bombardelli; S. S. Sengor; T. R. Ginn

2007-01-01

143

Molecular markers for identifying municipal, domestic and agricultural sources of organic matter in natural waters.  

PubMed

Molecular markers can be used to determine the sources of organic pollution in water. This review summarizes progress made during the last two decades in identifying reliable molecular markers to distinguish pollution from sewage, animal production, and other sources. Two artificial sweeteners, sucralose and acesulfame-K, are sufficiently stable to be molecular markers and easily associated with domestic wastewater. Waste from different animal species may be distinguished by profiling fecal sterols and bile acids. Other markers which have been evaluated, including caffeine, detergent components, and compounds commonly leached from landfills are discussed. PMID:24200048

Harwood, John J

2014-01-01

144

Water and sediment quality in the Yukon River basin, Alaska, during water year 2004  

USGS Publications Warehouse

This report contains water-quality and sediment-quality data from samples collected in the Yukon River Basin from March through September during the 2004 water year (WY). Samples were collected throughout the year at five stations in the basin (three on the main stem Yukon River, one each on the Tanana and Porcupine Rivers). A broad range of physical, chemical, and biological analyses are presented.

Schuster, Paul F.

2006-01-01

145

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

146

IDENTIFICATION OF STRESSORS IN TOXIC SEDIMENTS: WHOLE SEDIMENT AND INSTITIAL WATER RESULTS  

EPA Science Inventory

Identification of stressors in aquatic systems is critical to sound assessment and management of our nation's waterways. Information from stressor identification can be useful in designing effective sediment remediation methods, assessing options for sediment disposal, allowing m...

147

Microbial Diversity in Water and Sediment of Lake Chaka, an Athalassohaline Lake in Northwestern China  

PubMed Central

We employed culture-dependent and -independent techniques to study microbial diversity in Lake Chaka, a unique hypersaline lake (32.5% salinity) in northwest China. It is situated at 3,214 m above sea level in a dry climate. The average water depth is 2 to 3 cm. Halophilic isolates were obtained from the lake water, and halotolerant isolates were obtained from the shallow sediment. The isolates exhibited resistance to UV and gamma radiation. Microbial abundance in the sediments ranged from 108 cells/g at the water-sediment interface to 107 cells/g at a sediment depth of 42 cm. A major change in the bacterial community composition was observed across the interface. In the lake water, clone sequences affiliated with the Bacteroidetes were the most abundant, whereas in the sediments, sequences related to low G+C gram-positive bacteria were predominant. A similar change was also present in the archaeal community. While all archaeal clone sequences in the lake water belonged to the Halobacteriales, the majority of the sequences in the sediments were related to those previously obtained from methanogenic soils and sediments. The observed changes in the microbial community structure across the water-sediment interface were correlated with a decrease in salinity from the lake water (32.5%) to the sediments (approximately 4%). Across the interface, the redox state also changed from oxic to anoxic and may also have contributed to the observed shift in the microbial community. PMID:16751487

Jiang, Hongchen; Dong, Hailiang; Zhang, Gengxin; Yu, Bingsong; Chapman, Leah R.; Fields, Matthew W.

2006-01-01

148

Detection of Legionella spp. from Domestic Water in the Prefecture of Arta, Greece  

PubMed Central

The aim of this research was the isolation of Legionella spp. from domestic water supply networks in the Prefecture of Arta. A total of 100 water samples, from 25 houses, were collected. Half of the samples concerned the cold water and half the hot water supply. Purpose was to detect colonization of the water networks with Legionella spp. >500?cfu/L by using the method of filtration (ISO 11731). Out of 100 samples, 6 samples from 3 houses were positive for Legionella spp. Legionella pneumophila serogroup 2–14 was isolated in 5 of 6 samples, whereas in the sixth sample Legionella anisa was identified. Only three of the samples had residual chloride over 0.2?mg/L, rate which is necessary for potable water, according to the Greek hygienic practice. Concerning the temperature of hot water, the mean temperature of the negative for Legionella samples was higher compared to the mean temperature of the positive for Legionella samples (49.9°C versus 45.5°C). It is estimated that there is risk of infection through the use of showers. The low concentration of chloride and the temperature, which was found within the limits favorable to developing Legionella spp. (20–45°C), provide fertile ground for proliferation of the bacteria. PMID:24744922

Dimitriadi, Dimitra; Velonakis, Emmanuel

2014-01-01

149

Chemical quality of surface waters and sedimentation in the Saline River basin, Kansas  

USGS Publications Warehouse

This report gives the results of an investigation of the sediment and dissolved minerals that are transported by the Saline River and its tributaries. The Saline River basin is in western and central Kansas; it is long and narrow and covers 3,420 square miles of rolling plains, which is broken in some places by escarpments and small areas of badlands. In the western part the uppermost bedrock consists predominantly of calcareous elastic sedimentary rocks of continental origin of Pliocene age and in most places is covered by eolian deposits of Pleistocene and Recent age. In the central part the ex posed bedrock consists predominantly of calcareous marine sedimentary rocks of Late Cretaceous age. In the eastern part the exposed bedrock consists mainly of noncalcareous continental and littoral elastic sedimentary rocks of Early Cretaceous and Permian age. Fluvial deposits are in the valleys, and eolian materials are present over much of the uplands. Average precipitation increases rather uniformly from about 18 inches per year in the west to almost 28 inches per year in the east. Runoff is not affected by irrigation nor regulated by large structures, but it is closely related to precipitation. Average runoff increases from less than 0.2 inch per year in the west to more than 1.5 inches per year in the east. Aquifers of the flood-plain and terrace deposits and of the Cretaceous Dakota Sandstone are the major sources of ground-water accretion to the streams. In the upper reaches of the Saline River, the water is only slightly mineralized; during the period of record the specific conductance near Wakeeney never exceeded 750 micromhos per centimeter. In the lower reaches, however, the water is slightly mineralized during periods of high flow and is highly mineralized during periods of low flow; the specific conductance near Russell exceeded 1,500 micromhos per centimeter more than 80 percent of the time. Near Russell, near Wilson, and at Tescott the water is of the calcium bicarbonate type when the specific conductance is less than about 1,000 micromhos per centimeter, but it is of the sodium chloride type when the specific conductance is more than about 1,500 micromhos per centimeter. The water is off the calcium bicarbonate, sodium bicarbonate, or sodium chloride type when the conductance is between 1,000 and 1,500 micromhos per centimeter. Most of the increase in mineralization of the water is caused by inflow of highly mineralized ground water. The ground-water inflow was estimated to be 22 percent of the total streamflow at Tescott in 1948 and 60 percent in 1952. Mineralization increases and water quality deteriorates progressively downstream along nearly the entire Saline River, especially in the part of the area directly underlain by the Dakota Sandstone between the vicinities of Fairport and Wilson: sodium and chloride are the principal constituents of water contributed by the Dakota. The total percentage of the salt in the Saline River that comes from oil-field brines is considered to be small. The water in the upper Saline River is of good quality for domestic use except that it is hard; the water in the lower Saline River is of poor quality for domestic use because most of the time it is highly mineralized, is hard, and contains high concentrations of chloride and sulfate. In the upper reaches of the river, the water is of good quality for irrigation. In the lower reaches, if the water were impounded in a reservoir, it would be of good quality for irrigation during years of high flow and of very poor quality during years of low flow. The water in the lower reaches is of poor quality for industrial use because it is highly mineralized most of the tinge. Relations of suspended-sediment discharge to water discharge were used with the long-term streamflow duration curves to compute the long-term aver age suspended-sediment discharges and concentrations at five indications. Sediment discharge is closely related to runoff. S

Jordan, Paul Robert; Jones, B.F.; Petri, Lester R.

1964-01-01

150

Water and Sediment Quality in the Yukon River Basin, Alaska, During Water Year 2001  

USGS Publications Warehouse

Overview -- This report contains water-quality and sediment-quality data from samples collected in the Yukon River Basin during water year 2001 (October 2000 through September 2001). A broad range of chemical and biological analyses from three sets of samples are presented. First, samples were collected throughout the year at five stations in the basin (three on the mainstem Yukon River, one each on the Tanana and Porcupine Rivers). Second, fecal indicators were measured on samples from drinking-water supplies collected near four villages. Third, sediment cores from five lakes throughout the Yukon Basin were sampled to reconstruct historic trends in the atmospheric deposition of trace elements and hydrophobic organic compounds.

Schuster, Paul F.

2003-01-01

151

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

USGS Publications Warehouse

OVERVIEW: 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 the main stem Yukon River, one each on the Tanana and Porcupine Rivers). A broad range of physical, chemical, and biological analyses are presented. This is the final report in a series of five USGS Open-File Reports spanning five WYs, from October 2000 through September 2005. The previous four reports are listed in the references (Schuster, 2003, 2005a, 2005b, 2006). Water-quality and sediment-quality data from samples collected on the Yukon River and selected major tributaries in Alaska for synoptic studies during WYs 2002-03 are published in Dornblaser and Halm (2006).

Schuster, Paul F.

2007-01-01

152

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

153

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

2013-05-01

154

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

2013-01-01

155

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). PMID:23977190

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

2013-01-01

156

Water and Sediment Quality in the Yukon River and its Tributaries Between Atlin, British  

E-print Network

Water and Sediment Quality in the Yukon River and its Tributaries Between Atlin, British Columbia this report. Suggested citation: Halm, D.R., and Dornblaser, M.M., 2007, Water and sediment quality in the Yukon River and its tributaries between Atlin, British Columbia, Canada, and Eagle, Alaska, USA, 2004: U

157

Distribution of organochlorine pesticides in surface water and sediments from Qiantang River, East China  

Microsoft Academic Search

The levels of 13 organochlorine pesticides (OCPs) in surface water and sediments from Qiantang River in East China were investigated to evaluate their potential pollution and risks. A total of 180 surface water samples at 45 sampling sites and 48 sediment samples at 19 sampling stations were collected along the river in four seasons of 2005. Soil samples and wet

Rongbing Zhou; Lizhong Zhu; Kun Yang; Yuyun Chen

2006-01-01

158

Water and Sediment Quality of the Yukon River and its Tributaries, from Eagle to St. Marys,  

E-print Network

Water and Sediment Quality of the Yukon River and its Tributaries, from Eagle to St. Marys, Alaska-USGS Suggested citation: Dornblaser, Mark M., and Halm, Douglas R., eds., 2006, Water and Sediment Quality of the Yukon River and its Tributaries, from Eagle to St. Marys, Alaska, 2002­2003, U.S. Geological Survey

159

Zinc in the sediments, water and biota of Lake Burley Griffin, Canberra  

E-print Network

HI 235 Zinc in the sediments, water and biota of Lake Burley Griffin, Canberra W.A. Maher, RResearchCentre. Universityo/Canberra. P.O. Box /. BelconnenACT 26/6. Australia ABSTRAcr Zinc concentrations and total amounts in the sediment, water and biota of Lake Burley Griffin were measured to identify where zinc originating from

Canberra, University of

160

PRIMARY RESEARCH PAPER Water column oxygen demand and sediment oxygen flux  

E-print Network

PRIMARY RESEARCH PAPER Water column oxygen demand and sediment oxygen flux: patterns of oxygen dissolved oxygen (DO) levels often occur during summer in tidal creeks along the southeastern coast of the USA. We analyzed rates of oxygen loss as water-column biochemical oxygen demand (BOD5) and sediment

Mallin, Michael

161

Recent changes of water discharge and sediment load in the Zhujiang (Pearl River) Basin, China  

Microsoft Academic Search

The paper is concerned with identifying changes in the time series of water and sediment discharge of the Zhujiang (Pearl River), China. The gradual trend test (Mann–Kendall test), and abrupt change test (Pettitt test), have been employed on annual water discharge and sediment load series (from the 1950s–2004) at nine stations in the main channels and main tributaries of the

Shurong Zhang; Xi Xi Lu; David L. Higgitt; Chen-Tung Arthur Chen; Jingtai Han; Huiguo Sun

2008-01-01

162

Trace metal concentrations in water, sediments and fish tissue from Lake Tanganyika  

Microsoft Academic Search

Trace metal (Cu, Pb, Fe, Mn, Zn, Cd) concentrations were determined in water, sediments, various fin fish species and a bivalve (Mutelaspekei) from Lake Tanganyika using an atomic absorption spectrophotometer. Integrated water samples to depths of 10 m were collected using a pre-rinsed flexible plastic pipe. Sediment samples were collected using a ponar mud sampler. Fish samples were obtained using

F. M. M. Chale

2002-01-01

163

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

164

Sediment Inventory and Phosphorus Fractions for Water Conservation Area Canals in the Everglades  

E-print Network

Sediment Inventory and Phosphorus Fractions for Water Conservation Area Canals in the Everglades O in the Water Conservation Area (WCA) canals in the Ever- glades. A study was conducted to characterize

Florida, University of

165

Suspended sediment control and water quality conservation through riparian vegetation:  

NASA Astrophysics Data System (ADS)

Soil erosion and Suspended Sediment River are strongly related in the Apennines catchments which are generally characterised by a clayey lithology and impermeable soils and extensive and severe erosion and slope stability problems. In fact the suspended sediment yield represents one of the most reliable tools to assess real basin soil loss (Pavanelli and Pagliarani, 2002; Pavanelli and Rigotti, 2007) from the surface rain erosive features in a mountain watershed, as rills and interrills erosion, gullies, bad-lands (calanchi basins). Suspended sediment yield is known to imply several detrimental consequences: soil losses from agricultural land, worsening of the quality of the water, clogging of water supply filters and reservoir siltation. In addition, suspended sediment yield is also one of the main vector for pollutants and nutrients: various studies have already proved how nitrogen content has been constantly rising in aquifers and surface waters [Böhlke and Denver, 1995]. Finer particles and their aggregates have been proved to be the preferential vehicle for particulate nitrogen [Droppo et al., 1997; Ongley et al., 1992]. In one research [Pavanelli and al. 2006] four Apennines torrents (Gaiana, Sillaro, Savena and Lavino) with mountain basins ranging from 8.7 to 139 Km2 were monitored via automatic sampling devices, the samples of water collected were analysed to characterise suspended solids in terms of their grain size distribution and total nitrogen with respect to the source of eroded area in the catchment. Preliminary results [Pavanelli and al. 2007] seem to show the existence of a direct relationship between nitrogen concentration and finer particle concentration (<20 ?m), with the maximum nitrogen loss values being related to factors like the presence of clayey formations, their position within the catchment and the availability of suspended particles. The results seem to indicate hillsides as main sources of suspended sediment to the torrents monitored. The problem of controlling the river suspended sediment concentration can be tackled by increasing the riparian vegetation able to hold back the ground eroded by the slopes, but it is necessary to know where the critical zones are. The aim of the work is to propose a method allow us to detect the risk of soil erosion areas near the river and the functionality of existing riparian vegetation along river as buffers / filters towards the eroded soil from the hill slopes. The proposed methodology is supposed has been designed for water pollution control from suspended solids, pollutants and nutrients coming from hills and an improvement of the quality of the river environment. The methodology was applied on the riparian vegetation of the Gaiana torrent where it was related to soil cover and erosion areas of the hillslope, thus correlating the impact of human activities. The Gaiana catchment area is 8.6 km2 and the mean altitude is 237 a.m.s.l., the average rainfall is of 784 mm.. It is a typical Apennines streams, about 35 km south of Bologna, Italy. The main trunk stream is 6 km long and the whole drainage network is organized in a dendritic pattern, typical of clayey lithology of the basins. The main erosion processes active in the area are caused by precipitation and surface runoff: sheet wash, concentrated water erosion and badlands watersheds (calanchi), which represent about 15% of the basin area. The vegetation of the Gaiana basin is constituted by crops (39%), woods (37%), rock outcrops(i.e. badlands)(15%), bushes (5%) and pastures(3%). The stages of the study are to spot critical areas made up of streambank and the eroded areas on the slopes near the river, with the support of aerial photos and satellite images, survey and a geographic information system. The Gaiana riparian vegetation map has been drawn and, on a strip buffer 200 metres wide along river, the Vegetation cover and the Geomorphology maps (scale 1:5000) has been drawn, after photogrammetric interpretation of aerial photography and satellite images . The two maps have been overlapped to

Pavanelli, D.; Cavazza, C.; Correggiari, S.

2009-04-01

166

Sedimentation and water quality in the West Branch Shade River basin, Ohio, 1984 water year  

USGS Publications Warehouse

Sedimentation in, and flooding of, the West Branch Shade River and its tributaries have been major concerns of residents and State and local officials. The area was extensively surface mined for coal between the mid-1940 's and the early 1960's. Reclamation efforts immediately after mining were unsuccessful. The results have been elevated sediment loads and the subsequent loss of channel conveyance. Two sediment and stream gaging stations were established on West Branch Shade River in the area of past mining to provide data to evaluate the effectiveness of current reclamation activities on reducing sediment loads. A third station was established on the East Branch Shade River in an unmined area as a control. From October 1983 through September 1984, the annual suspended sediment yield/acre-ft of runoff was approximately two times as high for West Branch Shade River (0.51 ton/acre-ft of runoff) as for East Branch Shade River (0.28 ton/acre-ft). In addition, water quality of West Branch indicates that acidity is higher, pH is lower, and concentrations of dissolved sulfate and metals are higher than for East Branch. The concentration of coal in bed material increased in the downstream direction along West Branch Shade River. The concentration downstream in the West Branch was more than 20 times greater than in the East Branch. (Author 's abstract)

Childress, C.J.; Jones, R.L.

1985-01-01

167

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

NASA Astrophysics Data System (ADS)

Performance improvement of existing 200 litres capacity natural convection type domestic solar hot water system is attempted. A two-stage centrifugal pump driven by a vertical axis windmill having Savonius type rotor is added to the fluid loop. The windmill driven pump circulates the water through the collector. The system with necessary instrumentation is tested over a day. Tests on Natural Circulation System (NCS) mode and Wind Assisted System (WAS) mode are carried out during January, April, July and October, 2009. Test results of a clear day are reported. Daily average efficiency of 25-28 % during NCS mode and 33-37 % during WAS mode are obtained. With higher wind velocities, higher collector flow rates and hence higher efficiencies are obtained. In general, WAS mode provides improvements in efficiency when compared to NCS mode.

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

2011-08-01

168

Immobilization of phosphorus from water and sediment using zirconium-modified zeolites.  

PubMed

Adding sorbents to sediments has been suggested as an effective technology for contaminated sediment remediation. In this study, a zirconium-modified zeolite (ZrMZ) was prepared, characterized, and used as a sediment amendment to control phosphorus (P) release from eutrophic lake sediments. The efficiency of ZrMZ in immobilizing P from water and sediments was investigated through a series of experiments. The phosphate adsorption capacity for ZrMZ decreased with increasing water pH. The adsorption of phosphate on ZrMZ followed a pseudo-second-order kinetic model. The equilibrium adsorption data of phosphate on ZrMZ could be well described by the Langmuir isotherm model with a maximum monolayer adsorption capacity of 10.2 mg P/g at pH 7 and 25 °C. Sequential extraction of P from the phosphate-adsorbed ZrMZ suggested that most of P bound by ZrMZ existed as the NaOH extractable P (NaOH-P) and residual P (Res-P) and was unlikely to be released under natural pH and reducing conditions. The addition of ZrMZ into sediments reduced the inorganic P activity in the sediments by transforming bicarbonate-dithionite extractable P (BD-P) to NaOH-P and Res-P. The contents of bioavailable P such as water-soluble P (WS-P), NaHCO3 extractable P (Olsen-P), and algal available P (AAP) in sediments reduced after the sediments were mixed with ZrMZ, making P in the sediments more stable. The addition of ZrMZ into sediments significantly reduced the releasing flux of P from the sediments to the water column under different conditions. Results of this study indicate that the ZrMZ is a promising sediment amendment for controlling the internal P loading of lake sediments. PMID:25253056

Yang, Mengjuan; Lin, Jianwei; Zhan, Yanhui; Zhu, Zhiliang; Zhang, Honghua

2014-09-26

169

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

2012-11-01

170

Determining the optimum solar water pumping system for domestic use, livestock water, or irrigation  

Technology Transfer Automated Retrieval System (TEKTRAN)

For several years we have field tested many different types of solar powered water pumping systems. In this paper, several steps are given to select a solar-PV water pumping system. The steps for selection of stand-alone water pumping system were: deciding whether a wind or solar water pumping sys...

171

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

2010-10-01

172

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

173

Survey of the mutagenicity of surface water, sediments, and drinking water from the Penobscot Indian Nation.  

PubMed

U.S. Environmental Protection Agency (US EPA) Regional Applied Research Effort (RARE) projects address the effects of environmental pollutants in a particular region on the health of the population in that region. This report is part of a RARE project that addresses this for the Penobscot Indian Nation (PIN), Penobscot Island, Maine, U.S., where the Penobscot River has had fish advisories for many years due to high levels of mercury. We used the Salmonella mutagenicity assay with strains TA100, TA98, YG1041, and YG1042 with and without metabolic activation to assess the mutagenic potencies of organic extracts of the Penobscot River water and sediment, as well as drinking-water samples, all collected by the PIN Department of Natural Resources. The source water for the PIN drinking water is gravel-packed groundwater wells adjacent to the Penobscot River. Most samples of all extracts were either not mutagenic or had low to moderate mutagenic potencies. The average mutagenic potencies (revertants/L-equivalent) were 337 for the drinking-water extracts and 177 for the river-water extracts; the average mutagenic potency for the river-sediment extracts was 244 revertants(g-equivalent)(-1). This part of the RARE project showed that extracts of the Penobscot River water and sediments and Penobscot drinking water have little to no mutagenic activity that might be due to the classes of compounds that the Salmonella mutagenicity assay detects, such as polycyclic aromatic hydrocarbons (PAHs), nitro-PAHs (nitroarenes), and aromatic amines. This study is the first to examine the mutagenicity of environmental samples from a tribal nation in the U.S. PMID:25462314

Warren, Sarah H; Claxton, Larry D; Diliberto, Janet; Hughes, Thomas J; Swank, Adam; Kusnierz, Daniel H; Marshall, Valerie; DeMarini, David M

2015-02-01

174

Sediment Enzyme Activities and Microbial Community Diversity in an Oligotrophic Drinking Water Reservoir, Eastern China  

PubMed Central

Drinking water reservoir plays a vital role in the security of urban water supply, yet little is known about microbial community diversity harbored in the sediment of this oligotrophic freshwater environmental ecosystem. In the present study, integrating community level physiological profiles (CLPPs), nested polymerase chain reaction (PCR)-denaturing gradient gel electrophoresis (DGGE) and clone sequence technologies, we examined the sediment urease and protease activities, bacterial community functional diversity, genetic diversity of bacterial and fungal communities in sediments from six sampling sites of Zhou cun drinking water reservoir, eastern China. The results showed that sediment urease activity was markedly distinct along the sites, ranged from 2.48 to 11.81 mg NH3-N/(g·24h). The highest average well color development (AWCD) was found in site C, indicating the highest metabolic activity of heterotrophic bacterial community. Principal component analysis (PCA) revealed tremendous differences in the functional (metabolic) diversity patterns of the sediment bacterial communities from different sites. Meanwhile, DGGE fingerprints also indicated spatial changes of genetic diversity of sediment bacterial and fungal communities. The sequence BLAST analysis of all the sediment samples found that Comamonas sp. was the dominant bacterial species harbored in site A. Alternaria alternate, Allomyces macrogynus and Rhizophydium sp. were most commonly detected fungal species in sediments of the Zhou cun drinking water reservoir. The results from this work provide new insights about the heterogeneity of sediment microbial community metabolic activity and genetic diversity in the oligotrophic drinking water reservoir. PMID:24205265

Zhang, Haihan; Huang, Tinglin; Liu, Tingting

2013-01-01

175

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

NASA Astrophysics Data System (ADS)

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 recent years, problems associated with the management of contaminated dredged material, including high costs and the lack of suitable disposal/use alternatives, have threatened to impact the volume of shipping in the Harbor. Sources of contaminants include atmospheric deposition, municipal and industrial wastewater treatment facilities, combined sewer and stormwater outfalls, and rainfall-induced runoff (non-point sources). In addition, Harbor sediments can act as a continuing source as they are re-suspended and moved throughout the system by both natural and man-made means. As part of the New Jersey Toxics Reduction Workplan, Stevens Institute of Technology and Rutgers University are conducting hydrodynamic, sediment transport, and water and suspended sediment quality measurements in Newark Bay, the Arthur Kill and the Kill van Kull. The goals of the project include: (1) collection of high resolution (event-driven and long-term) hydrodynamic, sediment transport and water and suspended sediment quality measurements for use in the assessment of the dominant physics of the system and in the development of a combined hydrodynamic-sediment transport-water/sediment quality model for the region. (2) identification of those tributaries to NY-NJ Harbor that are significant sources of the chemicals of concern, and evaluation of the importance of non-point sources and existing contaminated bottom sediments as sources of the chemicals of concern. (3) identification of point discharges that represent significant sources of the chemicals of concern. Observations were obtained over a two-year period, during 21 tributary flow "events", each having an approximate duration of 1 week. The measurement program included 3 fixed mooring stations and 5 shipboard locations. Each mooring consisted of an acoustic Doppler current profiler; a high-resolution pressure sensor; an OBS; a CTD; and a laser-based scatterometer. The ship-board measurements included vertical current profiles using a towed acoustic Doppler current profiler; CTD measurements; OBS measurements; suspended sediment concentration and particle size spectrum using a laser-based scatterometer; and chemical characterization of water and suspended sediment samples. The water and sediment quality measurements were obtained using a specially designed Trace Organics Platform Sampler. This sampler allowed for the measurement of low-level concentrations of PCBs (108 congeners), dioxins/furans, Pesticides, PAHs and metals (Hg, Cd, Pb). Preliminary analysis of the data has improved our understanding of the circulation and sediment transport patterns in this region of the estuary, including the influence of extreme tributary flow events, local winds, and anthropogenic effects such as port structures, vessels, and the navigation channels, and has identified the most highly contaminated reaches of the tributaries.

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

2002-12-01

176

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

177

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

178

Where There Is No Toilet: Water and Sanitation Environments of Domestic and Facility Births in Tanzania  

PubMed Central

Background Inadequate water and sanitation during childbirth are likely to lead to poor maternal and newborn outcomes. This paper uses existing data sources to assess the water and sanitation (WATSAN) environment surrounding births in Tanzania in order to interrogate whether such estimates could be useful for guiding research, policy and monitoring initiatives. Methods We used the most recent Tanzania Demographic and Health Survey (DHS) to characterise the delivery location of births occurring between 2005 and 2010. Births occurring in domestic environments were characterised as WATSAN-safe if the home fulfilled international definitions of improved water and improved sanitation access. We used the 2006 Service Provision Assessment survey to characterise the WATSAN environment of facilities that conduct deliveries. We combined estimates from both surveys to describe the proportion of all births occurring in WATSAN-safe environments and conducted an equity analysis based on DHS wealth quintiles and eight geographic zones. Results 42.9% (95% confidence interval: 41.6%–44.2%) of all births occurred in the woman's home. Among these, only 1.5% (95% confidence interval: 1.2%–2.0%) were estimated to have taken place in WATSAN-safe conditions. 74% of all health facilities conducted deliveries. Among these, only 44% of facilities overall and 24% of facility delivery rooms were WATSAN-safe. Combining the estimates, we showed that 30.5% of all births in Tanzania took place in a WATSAN-safe environment (range of uncertainty 25%–42%). Large wealth-based inequalities existed in the proportion of births occurring in domestic environments based on wealth quintile and geographical zone. Conclusion Existing data sources can be useful in national monitoring and prioritisation of interventions to improve poor WATSAN environments during childbirth. However, a better conceptual understanding of potentially harmful exposures and better data are needed in order to devise and apply more empirical definitions of WATSAN-safe environments, both at home and in facilities. PMID:25191753

Benova, Lenka; Cumming, Oliver; Gordon, Bruce A.; Magoma, Moke; Campbell, Oona M. R.

2014-01-01

179

The chemical quality of self-supplied domestic well water in the United States  

USGS Publications Warehouse

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 some wells sampled in every state and Puerto Rico. Inorganic contaminants were detected in many of the wells, and concentrations exceeded the U.S. EPA maximum contaminant levels (MCLs; federal drinking water standards used to regulate public drinking water quality) more often than organic contaminants. Of the inorganic constituents evaluated, arsenic concentrations exceeded the MCL (10 ??g/L) in ???11% of the 7580 wells evaluated, nitrate exceeded the MCL (10 mg/L) in ???8% of the 3465 wells evaluated, uranium-238 exceeded the MCL (30 ??g/L) in ???4% of the wells, and radon-222 exceeded 300 and 4000 pCi/L (potential drinking water standards currently under review by the U.S. EPA) in ???75% and 9% of the wells, respectively. The MCLs for total mercury and fluoride were each exceeded in <1% of the wells evaluated. The MCL was exceeded in <1% of all wells for all anthropogenically derived organic contaminants evaluated and was not exceeded for many contaminants. In addition, 10 contaminants evaluated do not currently have an MCL. Atrazine, however, was detected in 24% of the wells evaluated and was the most frequently detected organic contaminant of the 28 organic contaminants evaluated in this study. Simazine and metolachlor each were detected in ???9% of all wells and tied for second in frequency of detection for organic contaminants. The third and fourth most frequently detected organic contaminants were methyl tert-butyl ether (MTBE) (6%) and chloroform (5%), respectively. Because the water quality of domestic wells is not federally regulated or nationally monitored, this study provides a unique, previously nonexistent, perspective on the quality of the self-supplied drinking water resources used by ???45 million Americans in the United States. Copyright ?? 2006 The Author(s).

Focazio, M.J.; Tipton, D.; Dunkle, Shapiro S.; Geiger, L.H.

2006-01-01

180

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

181

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

2013-01-01

182

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

183

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

184

Pesticide contamination and phytotoxicity of sediment interstitial water to tropical benthic microalgae.  

PubMed

Many organic compounds including some herbicides concentrate in sediment, thus it may be expected that interstitial waters contain higher concentrations of these contaminants than the water column. To estimate benthic microalgal exposure to pesticides, sediment and interstitial water sampled in the dry season from four major rivers in north Queensland, Australia, were analysed for these contaminants. Interstitial water extracts from the sediments were tested for acute phytotoxicity to benthic microalgae using PAM fluorometry and the results were compared with chemical analyses of the same water samples. A range of pesticides were detected in both sediment and interstitial waters from all sites, notably the herbicide diuron at concentrations ranging from 0.3 to 11 ?g kg(-1) dry weight sediment, and up to 68 ng L(-1) in interstitial waters. Herbicide concentrations estimated from partition coefficients and the sediment concentrations typically overestimated analytically determined concentrations present in interstitial water by an order of magnitude. The analytically determined herbicide concentrations in the interstitial water explained most of the phytotoxicity measured with the bioassay; however, photoinhibition was slightly higher than expected based on analytical results, indicating the presence of unidentified phytotoxins. These results demonstrate the presence of pesticides in interstitial waters in the Tropical dry season, sometimes at concentrations that may affect sensitive benthic organisms, and supports the use of the I-PAM bioassay as a valuable tool in exposure- and environmental risk- and impact-assessments. PMID:23870432

Magnusson, Marie; Heimann, Kirsten; Ridd, Michael; Negri, Andrew P

2013-09-15

185

Levels of PAHs in the Waters, Sediments, and Shrimps of Estero de Urias, an Estuary in Mexico, and Their Toxicological Effects  

PubMed Central

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

2012-01-01

186

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

187

Water permeability in hydrate-bearing sediments: A pore-scale study  

NASA Astrophysics Data System (ADS)

is a critical parameter governing methane flux and fluid flow in hydrate-bearing sediments; however, limited valid data are available due to experimental challenges. Here we investigate the relationship between apparent water permeability (k') and hydrate saturation (Sh), accounting for hydrate pore-scale growth habit and meso-scale heterogeneity. Results from capillary tube models rely on cross-sectional tube shapes and hydrate pore habits, thus are appropriate only for sediments with uniform hydrate distribution and known hydrate pore character. Given our pore network modeling results showing that accumulating hydrate in sediments decreases sediment porosity and increases hydraulic tortuosity, we propose a modified Kozeny-Carman model to characterize water permeability in hydrate-bearing sediments. This model agrees well with experimental results and can be easily implemented in reservoir simulators with no empirical variables other than Sh. Results are also relevant to flow through other natural sediments that undergo diagenesis, salt precipitation, or bio-clogging.

Dai, Sheng; Seol, Yongkoo

2014-06-01

188

Parameterization of biogeochemical sediment-water fluxes using in-situ measurements and a steady-state diagenetic model  

NASA Astrophysics Data System (ADS)

Sediment biogeochemical processes are important drivers of water column biogeochemistry in coastal areas. For example, sediment oxygen consumption can be an important driver of bottom water oxygen depletion in hypoxic systems, and sediment-water nutrient fluxes support primary productivity in the overlying water column. Yet, biogeochemical sediment-water fluxes are often parameterized crudely and only poorly constrained in coupled physical-biogeochemical models. Here, we present a method for parameterizing biogeochemical sediment-water fluxes realistically and efficiently, using in-situ measurements and a steady state diagenetic model. We apply this method to the Louisiana Shelf where high primary production induced by excess nutrient loads from the Mississippi-Atchafalaya River system promotes the development of hypoxic bottom waters in summer. The implementation of the parameterizations in a coupled circulation-biogeochemical model of the northern Gulf of Mexico results in realistic sediment-water fluxes that enable a sediment-water column feedback at low bottom oxygen concentrations.

Laurent, Arnaud; Fennel, Katja; Wilson, Robin; Lehrter, John; Devereux, Richard

2014-05-01

189

Water quality and sediment geochemistry in lakes of Yunnan Province, southern China  

Microsoft Academic Search

Yungui Plateau lakes in southwestern China are economically important, although few have been studied previously. Water and\\u000a sediments of 24 lakes throughout Yunnan Province were sampled in October 1994. We describe the chemical and physical characteristics\\u000a of Yunnan lakes, and address effects of regional geology and human influences on water quality and sediment type. Water quality\\u000a differs between deep Yunnan

T. J. Whitmore; M. Brenner; Z. Jiang; J. H. Curtis; A. M. Moore; D. R. Engstrom; Y. Wu

1997-01-01

190

Processing of combined domestic bath and laundry waste waters for reuse as commode flushing water  

NASA Technical Reports Server (NTRS)

An experimental investigation of processes and system configurations for reclaiming combined bath and laundry waste waters for reuse as commode flush water was conducted. A 90-min recycle flow was effective in removing particulates and in improving other physical characteristics to the extent that the filtered water was subjectively acceptable for reuse. The addition of a charcoal filter resulted in noticeable improvements in color, turbidity, and suds elimination. Heating and chlorination of the waste waters were investigated for reducing total organism counts and eliminating coliform organisms. A temperature of 335.9 K (145 F) for 30 min and chlorine concentrations of 20 mg/l in the collection tank followed by 10 mg/l in the storage tank were determined to be adequate for this purpose. Water volume relationships and energy-use rates for the waste water reuse systems are also discussed.

Hypes, W. D.; Batten, C. E.; Wilkins, J. R.

1975-01-01

191

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

192

Ecosystem engineering at the sediment–water interface: bioturbation and consumer-substrate interaction  

Microsoft Academic Search

In soft-bottom sediments, consumers may influence ecosystem function more via engineering that alters abiotic resources than\\u000a through trophic influences. Understanding the influence of bioturbation on physical, chemical, and biological processes of\\u000a the water–sediment interface requires investigating top-down (consumer) and bottom-up (resource) forces. The objective of\\u000a the present study was to determine how consumer bioturbation mode and sediment properties interact to

Géraldine Nogaro; Florian Mermillod-Blondin; Maurice H. Valett; Frédérique François-Carcaillet; Jean-Paul Gaudet; Michel Lafont; Janine Gibert

2009-01-01

193

Interstitial water chemistry of anoxic Long Island Sound sediments. 2. Nutrient regeneration and phosphate removal1  

Microsoft Academic Search

The stoichiometry of nutrient regeneration in anoxic Long Island Sound sediments is ex- amined through changes in the concentration of dissolved sulfate, ammonia, reactive phos- phate, and other chemical species with depth in interstitial waters. In offshore sediments the mean AS04:ANH4:ACP ratio is -53:4.6:0.37; in shallow harbor sediment it is -53: 19:3.3 and ANI14:AZP ratios are half the offshore ratio.

Christopher S. Martens; Robert A. Berner; Jeffrey K. Rosenfeld

194

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

195

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

Microsoft Academic Search

Phosphorus (P) fractions and the effect of phytoremediation on nitrogen and phosphorus removal from eutrophicated water and\\u000a release from sediment were investigated in the eco-remediation experiment enclosures installed in the Hua-jia-chi pond (Hangzhou\\u000a city, Zhejiang province, China). The main P fraction in the sediment was inorganic phosphorus (IP). For the mesotrophic sediments,\\u000a IP mainly consisted of HCl-extractable P (Ca-P). The

Wu Xiang; Yang Xiao-E; Zed Rengel

2009-01-01

196

ECO: a generic eutrophication model including comprehensive sediment-water interaction.  

PubMed

The content and calibration of the comprehensive generic 3D eutrophication model ECO for water and sediment quality is presented. Based on a computational grid for water and sediment, ECO is used as a tool for water quality management to simulate concentrations and mass fluxes of nutrients (N, P, Si), phytoplankton species, detrital organic matter, electron acceptors and related substances. ECO combines integral simulation of water and sediment quality with sediment diagenesis and closed mass balances. Its advanced process formulations for substances in the water column and the bed sediment were developed to allow for a much more dynamic calculation of the sediment-water exchange fluxes of nutrients as resulting from steep concentration gradients across the sediment-water interface than is possible with other eutrophication models. ECO is to more accurately calculate the accumulation of organic matter and nutrients in the sediment, and to allow for more accurate prediction of phytoplankton biomass and water quality in response to mitigative measures such as nutrient load reduction. ECO was calibrated for shallow Lake Veluwe (The Netherlands). Due to restoration measures this lake underwent a transition from hypertrophic conditions to moderately eutrophic conditions, leading to the extensive colonization by submerged macrophytes. ECO reproduces observed water quality well for the transition period of ten years. The values of its process coefficients are in line with ranges derived from literature. ECO's calculation results underline the importance of redox processes and phosphate speciation for the nutrient return fluxes. Among other things, the results suggest that authigenic formation of a stable apatite-like mineral in the sediment can contribute significantly to oligotrophication of a lake after a phosphorus load reduction. PMID:23844160

Smits, Johannes G C; van Beek, Jan K L

2013-01-01

197

Chemical quality of surface waters, and sedimentation in the Grand River drainage basin, North and South Dakota  

USGS Publications Warehouse

An investigation of the chemical quality of surface waters and of the sedimentation in the Grand River drainage basin by the U.S. Geological Survey began in 1946. The chemical quality of the water was studied to obtain information on the nature and amounts of dissolved solids in the streams and on the suitability of the water for domestic, industrial, and irrigation uses. Sedimentation was studied to determine the quantity of sediment that is transported by the streams, the particle sizes of the sediment, and the probable specific weight of the sediment when deposited in a reservoir. The basin is underlain by consolidated sedimentary rocks of Cretaceous and Tertiary age; along the Grand River and its tributaries the rocks are mantled by alluvium of Quaternary age. The Hell Creek and Fort Union Formations underlie about 4,700 of the 5,680 square miles of drainage area. The climate of the basin is semiarid and is characterized by hot summers and cold winters. Mean annual runoff is about 53 acre-feet per square mile of drainage area and is equal to about 7 percent of the mean annual precipitation. The highest streamflows on the Grand River and major tributaries are caused by melting of snow in March and April. Streamflow is extremely variable from year to year. Most of the surface waters in the basin are of the sodium sulfate or sodium bicarbonate type. High percent sodium is typical of almost all the surface waters. The streamflow-quality patterns of the Grand River and its two forks are very similar; dissolved-solids concentration, which usually does not exceed 3,000 ppm, is maximum during low-flow periods. The water in Shadehill Reservoir became stratified during the flood inflow of 1952; about 75 percent of the floodwater, which was of good quality, passed through the reservoir. The quality of the water became almost uniform throughout the reservoir the latter part of July 1952. After the specific conductance became relatively stable in 1956, it fluctuated from about 1,300 to 1,600 micromhos per centimeter and was between 1,400 and 1,500 micromhos per centimeter most of the time. During the representative period July 1937 to June 1950 the quantity of dissolved solids passing the station near Wakpala was estimated to have been about 140,000 tons per year. Yields computed for different parts of the basin ranged from about 22 to 32 tons per square mile. Except for sulfate, concentrations of chemical constituents usually do not exceed the maximum concentrations recommended for domestic supplies. The rather high dissolved solids, and hardness of most of the surface waters prevent the use of these waters for most industrial purposes unless the quality is improved by treatment. Classified for irrigation use according to its specific conductance and sodium-adsorption-ratio, the water stored in Shadehill Reservoir has a high salinity hazard and a medium sodium hazard. The water can be used safely for sustained irrigation on soils of the proposed irrigation unit if adequate leaching is practiced and if gypsum or some other calcium compound is added to the water or land during the high sodium cycle. Suspended-sediment discharges of the Grand River at Shadehill from March 1946 through July 1950 averaged 700,000 tons per year. Suspended-sediment discharges of the South Fork Grand River near Cash for 1947-50, estimated from periodic measurements, averaged 270,000 tons per year. Sediment discharges during these periods were much greater than normal. Suspended-sediment discharges of the North Fork Grand River for 1947-60, estimated from periodic measurements, averaged 31,000 tons per year at Haley and 140,000 tons per year near White Butte. Suspended sediment is predominantly clay ; some silt and a little sand are transported. The probable specific weights of sediment deposits are about 42 pounds per cubic foot for the North and South Forks and 56 pounds per cubic foot for the Grand River at Shadehill. These speci

Hembree, Charles Herbert; Krieger, Robert A.; Jordan, Paul Robert

1964-01-01

198

Toxicity of phthalates to selected benthic organisms via water and sediment exposures  

SciTech Connect

A three-tiered approach was applied to evaluate the bioavailability and toxicity of a series of phthalic acid esters to selected benthic invertebrates. Tier 1 consisted of 10-day exposures of the test species to the phthalates in water without sediments to determine toxicity. Tier 2 consisted of incorporating the phthalates into natural sediments and evaluating their persistence in phthalate-amended sediments under conditions simulating those of a 10-day toxicity test of contaminated sediments. Tier 3 consisted of performing 10-day exposures of test animals to phthalate-amended sediments. Phthalates were amended to sediments for Tier 3 testing based upon the results of Tier 1 and Tier 2 tests, and an estimation of partitioning between sediment and pore water based upon equilibrium partitioning theory (EPT). Sediments of varying organic carbon content were used to evaluate the bioavailability and toxicity of phthalate-amended sediments. The phthalates included in this study were dimethyl, diethyl, di-n-butyl, butylbenzyl, di-n-hexyl, di-2-ethylhexyl and di-n-decyl phthalate. The sensitivities of the three test species followed the general order in water-only tests: Hyalella azteca > Chironomus tentans > Lumbriculus variegatus. The persistence of selected phthalates from Tier 2 tests, their respective toxicities from Tier 3 tests, and the utility of the EPT approach in assessing phthalate toxicity will be discussed.

Call, D.J.; Markee, T.P.; VandeVenter, F.A.; Cox, D.A.; Geiger, D.L.; Brooke, L.T. [univ. of Wisconsin, Superior, WI (United States). Lake Superior Research Inst.

1995-12-31

199

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

200

Contamination of nonylphenolic compounds in creek water, wastewater treatment plant effluents, and sediments from Lake Shihwa and vicinity, Korea: Comparison with fecal pollution  

USGS Publications Warehouse

Nonylphenolic compounds (NPs), coprostanol (COP), and cholestanol, major contaminants in industrial and domestic wastewaters, were analyzed in creek water, wastewater treatment plant (WWTP) effluent, and sediment samples from artificial Lake Shihwa and its vicinity, one of the most industrialized regions in Korea. We also determined mass discharge of NPs and COP, a fecal sterol, into the lake, to understand the linkage between discharge and sediment contamination. Total NP (the sum of nonylphenol, and nonylphenol mono- and di-ethoxylates) were 0.32–875 ?g L-1 in creeks, 0.61–87.0 ?g L-1 in WWTP effluents, and 29.3–230 ?g g-1 TOC in sediments. Concentrations of COP were 0.09–19.0 ?g L-1 in creeks, 0.11–44.0 ?g L-1 in WWTP effluents, and 2.51–438 ?g g-1 TOC in sediments. The spatial distributions of NPs in creeks and sediments from the inshore region were different from those of COP, suggesting that Lake Shihwa contamination patterns from industrial effluents differ from those from domestic effluents. The mass discharge from the combined outfall of the WWTPs, located in the offshore region, was 2.27 kg d-1 for NPs and 1.00 kg d-1 for COP, accounting for 91% and 95% of the total discharge into Lake Shihwa, respectively. The highest concentrations of NPs and COP in sediments were found in samples at sites near the submarine outfall of the WWTPs, indicating that the submarine outfall is an important point source of wastewater pollution in Lake Shihwa.

Choi, Minkyu; Furlong, Edward T.; Moon, Hyo-Bang; Yu, Jun; Choi, Hee-Gu

2011-01-01

201

Interparticle collision of natural sediment grains in water  

USGS Publications Warehouse

Elastohydrodynamic theory and measurements of particle impacts on an inclined glass plane in water are used to investigate the mechanics of interparticle collisions in sediment-transporting flows. A collision Stokes number is proposed as a measure of the momentum of an interparticle collision versus the viscous pressure force in the interstitial gap between colliding particles. The viscous pressure force opposes motion of the particles on approach and rebound. A Stokes number of between 39 and 105 is estimated as the critical range below which particle impacts are completely viscously damped and above which impacts are partially elastic. The critical Stokes number is shown to roughly coincide with the Bagnold number transition between macroviscous and grain inertial debris flows and the transition between damped and partially elastic bed load transport saltation impacts. The nonspherical nature of natural particles significantly alters the motion of the center of mass after a partially elastic collision. The normal to the point of contact between the particles does not necessarily go through the center of mass. Thus normal rebound of the center of mass may not occur. A model of particle motion after rebound for particles of arbitrary shape, conserving both linear and angular momentum, is proposed.

Schmeeckle, M.W.; Nelson, J.M.; Pitlick, J.; Bennett, J.P.

2001-01-01

202

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

203

A vacuum-operated pore-water extractor for estuarine and freshwater sediments  

USGS Publications Warehouse

A vacuum-operated pore-water extractor for estuarine and freshwater sediments was developed and constructed from a fused-glass air stone attached with aquarium airline tubing to a 30 or 60 cc polypropylene syringe. Pore water is extracted by inserting the air stone into the sediment and creating a vacuum by retracting and bracing the syringe plunger. A hand-operated vacuum pump attached to a filtration flask was also evaluated as an alternative vacuum source. The volume and time to extract pore water varies with the number of devices and the sediment particle size. Extraction time is longer for fine sediments than for sandy sediments. Four liters of sediment generally yield between 500 and 1,500 mL of pore water. The sediment that surrounds and accumulates on the air stone acts as a filter, and, except for the first few milliliters, the collected pore water is clear. Because there is no exposure to air or avenue for escape, volatile compounds andin situ characteristics are retained in the extracted pore water.

Winger, P.V.; Lasier, P.J.

1991-01-01

204

Physiological Response of Rainbow Trout to Sediment Released during Open-Cut Pipeline Water Crossing Construction  

Microsoft Academic Search

The physiological response of rainbow trout exposed to elevated suspended sediment concentrations downstream of two open-cut pipeline water crossings was investigated. Trout held in cages downstream of construction had increased respiration rates and shorter times till loss of equilibrium during sealed jar bioassays. Differences in blood hematocrit levels between experiments and transects is attributed to sediment concentration and particle size.

SCOTT M. REID; GLENN ISAAC; SERGE METIKOSH; JIM EVANS

2003-01-01

205

Microphytobenthos activity and fluxes at the sediment-water interface: interactions and spatial variability  

Microsoft Academic Search

In this study oxygen and nutrient fluxes and denitrification rates across the sediment-water interface were measured via intact core incubations with a twofold aim: show whether microphytobenthos activity affects these processes and analyse the dispersion of replicate measurements. Eighteen intact sediment cores (i.d. 8 cm) were randomly sampled from a shallow microtidal brackish pond at Tjarno, on the west coast

Marco Bartoli; Daniele Nizzoli; Pierluigi Viaroli

2003-01-01

206

A reservoir operating method for riverine ecosystem protection, reservoir sedimentation control and water supply  

NASA Astrophysics Data System (ADS)

Riverine ecosystem protection requires the maintenance of natural flow and sediment regimes downstream from dams. In reservoir management schedules this requirement should be integrated with sedimentation control and human water supply. However, traditional eco-friendly reservoir operating methods have usually only considered the natural flow regime. This paper seeks to develop a reservoir operating method that accounts for both the natural flow and sediment regimes as well as optimizing the water supply allocations. Herein, reservoir water level (RWL), sediment-occupied ratio of reservoir volume (SOR) and rate of change of SOR (RCSOR) are adopted as three triggers of a drawdown-flushing-based sediment management policy. Two different groups of reservoir operating rule curves (RORCs) are designed for sediment-flushing and non-sediment-flushing years, and the three triggers, RWL, SOR and RCSOR, are used to change the “static” RORCs to “dynamic” ones. The approach is applied to the Wangkuai Reservoir, China to test its effectiveness. This shows that the approach can improve the flexibility of reservoir operators to balance the reservoir management, water supply management and the flow and sediment needs of the downstream riverine ecosystem.

Yin, Xin-An; Yang, Zhi-Feng; Petts, Geoffrey E.; Kondolf, G. Mathias

2014-05-01

207

IMPACT OF STORM-WATER OUTFALLS ON SEDIMENT QUALITY IN CORPUS CHRISTI BAY, TEXAS, USA  

EPA Science Inventory

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., industr...

208

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...

209

AUTOMATED LONG-TERM REMOTE MONITORING OF SEDIMENT-WATER INTERFACIAL FLUX  

EPA Science Inventory

Advective flux across the sediment-water interface is temporally and spatially heterogeneous in nature. For contaminated sediment sites, monitoring spatial as well as temporal variation of advective flux is of importance to proper risk management. This project was conducted to ...

210

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

211

DEGRATION OF SELECTED HALOGENATED ETHANES IN ANOXIC SEDIMENT-WATER SYSTEMS  

EPA Science Inventory

The degradation of selected halogenated ethanes was studied in anoxic sediment-water suspensions at 1 to 20% sediment concentrations. Batch kinetic experiments were used to quantify decay. Eh measurements of all suspensions were below -100mV (vs SHE), indicating reduced environme...

212

PCB fluxes from the sediment to the water column following resuspension A column experiment  

E-print Network

, have been specially designed to study PCB behavior during sediment resuspension, settlingPCB fluxes from the sediment to the water column following resuspension ­ A column experiment was systematically due to significant levels of PCB-DL and PCDD/F in fish tissue. New campaigns of characterization

Paris-Sud XI, Université de

213

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

214

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...

215

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

216

One Machine for Heating Cooling & Domestic Hot Water: Multi-Function Heat Pumps to Enable Zero Net Energy Homes  

E-print Network

, vapor-compression forced-air systems for cooling, and gas-fired storage systems for domestic water the annual drive cycle of an all-electric sedan. The heat-pump in this home is designed to cover all heating

California at Davis, University of

217

INSTALLATION CERTIFICATE CF-6R-MECH-02 Solar Domestic Hot Water Systems (SDHW) (Page 1 of 1)  

E-print Network

INSTALLATION CERTIFICATE CF-6R-MECH-02 Solar Domestic Hot Water Systems (SDHW) (Page 1 of 1) Site HEATING SYSTEMS: SRCC Certified Mfr Name & Model Number Net Solar Fraction (from attached CEC F-Chart) # of Collectors in System Collector Size Solar Tank Volume (gallons) §150(j)1B: Backup storage tanks for solar

218

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

219

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

220

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

2011-12-01

221

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

222

Nutrient exchange and release experiment and its simulation study in lake water-sediment interface.  

PubMed

The sediment distributed and insolated under lake was collected for experiments. The nutrient layer distribution conditions of sampled sediment and its physical and chemical characteristics were analyzed to simulate and assess the influence degree to lake water quality. Based on the dynamic water exchanging experiments the nutrient release process in sediment and influence mechanism to substance exchanging on water-sediment interface was studied, and the correlation between the changing content of total phosphors and total nitrogen in sediment and covered water were analyzed for setting up a simulation model. At the same time the influence degree is explained in detail. The experimental results indicated that even if clean water without nutrient contents was used for water exchangement so as to decrease pollution or prevent eutrophication, however owing to the vertical nutrient distribution in lake sediment, it will lead to the increasing release amount greatly especially when the organic nutrient contained in sediment turns into inorganic status because of isolation. Besides the release process of total phosphate (TP) and total nitrogen (TN) were modeled and each nutrient's exchanging equation at interface caused by covered water nutrient concentration changing was set up. According to the simulating prediction, TP and TN content of cover water will also sustain a steady higher level in a long period. The nutrient release amount of sediment is not only affected by the covered water concentration but also connects with accumulative time. The experiments provide the fundamental theoretical and practical basis for taking ecological restoration project. And research is helpful to prevent or restore lake eutrophication. PMID:17294663

Xue, Lian-Qing; Hao, Zhen-Chun

2006-01-01

223

Extraction of PCBs and water from river sediment using liquefied dimethyl ether as an extractant.  

PubMed

We investigated whether polychlorinated biphenyls (PCBs) and water could be simultaneously removed from river sediment by solvent extraction using liquefied dimethyl ether (DME) as the extractant. DME exists in a gaseous state at normal temperature and pressure and can dissolve organic substances and some amount of water; therefore, liquefied DME under moderate pressure (0.6-0.8 MPa) at room temperature can be effectively used to extract PCBs and water from contaminated sediment, and it can be recovered from the extract and reused easily. First, we evaluated the PCB and water extraction characteristics of DME from contaminated sediment. We found that 99% of PCBs and 97% of water were simultaneously extracted from the sediment using liquefied DME at an extraction time of 4320 s and a liquefied DME/sediment ratio of 60 mL g(-1). The extraction rate of PCBs and water was expressed in terms of a pseudo-first-order reaction rate. Second, we estimated the amount of DME that was recovered after extraction. We found that 91-92% of DME could be recovered. In other words, approximately 5-10% of DME was lost during extraction and recovery. It is necessary to optimize this process in order to recover DME efficiently. The extraction efficiency of the recovered DME is similar to that of the pure DME. From the results, we conclude that solvent extraction using liquefied DME is suitable for extracting PCBs and water from contaminated sediment. PMID:20044120

Oshita, Kazuyuki; Takaoka, Masaki; Kitade, Sin-ichiro; Takeda, Nobuo; Kanda, Hideki; Makino, Hisao; Matsumoto, Tadao; Morisawa, Shinsuke

2010-02-01

224

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

Code of Federal Regulations, 2012 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...

2012-07-01

225

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

226

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

Code of Federal Regulations, 2014 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...

2014-07-01

227

MONITORING OXIDATION-REDUCTION PROCESSES IN GROUND WATERS, SEDIMENTS, AND SOILS  

EPA Science Inventory

The overall goal of this project is to develop recommendations and technical guidelines for evaluating redox processes in contaminated ground water, sediment, and soil systems. One specific goal is to evaluate existing methodologies for determining Dissolved Oxygen (DO) concentra...

228

THE MEASURE OF RATES OF NUTRIENT FLUXES BETWEEN TAMPA BAY SEDIMENTS AND THE OVERLYING WATER COLUMN  

EPA Science Inventory

The project will measure rates of nutrient fluxes between Tampa Bay sediments and the ovrelying water column. This information has been lacking from previous nitrogen budgets for Tampa Bay, potentially hampering their accuracy and effectiveness. Refined nitrogen budgets based o...

229

Three-dimensional acoustic propagation through shallow water internal, surface gravity and bottom sediment waves  

E-print Network

This thesis describes the physics of fully three-dimensional low frequency acoustic interaction with internal waves, bottom sediment waves and surface swell waves that are often observed in shallow waters and on continental ...

Shmelev, Alexey Alexandrovich

2011-01-01

230

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...

231

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

Code of Federal Regulations, 2010 CFR

...MANDATORY SAFETY STANDARDS, SURFACE COAL MINES AND SURFACE WORK AREAS OF UNDERGROUND COAL MINES Surface Installations § 77.216-4 Water, sediment or slurry impoundments...minimum, maximum, and present depth and elevation of the...

2010-07-01

232

Fremont Lake, Wyoming--some aspects of the inflow of water and sediment  

USGS Publications Warehouse

Fremont Lake is a large (20.6 sq km), deep lake (185 m) in western Wyoming. Average annual inflow of water is about 5.1 cu meters/sec, and this discharge is equaled or exceeded about 23% of the time. Annual instantaneous peak flows of Pine Creek usually exceed 30 cu m/sec and the 100-year flood is about 80 cu m/sec. About 800 tons of sediment are delivered to the lake annually; annual deposition of sediment in the northern lake area throughout the last 10,000 years about equals contemporary values of sediment inflow. Only small quantities of fine-gradient sediment are transported beyond the delta at the northern end of the lake. Current rates of deposition in the delta are about 1 to 3 mm/yr. Sediment in the delta generally is sand size; elsewhere in the lake, sediment generally is clay and silt size. (USGS)

Emmett, W.W.; Averett, R.C.

1989-01-01

233

Characterization of bottom-sediment, water, and elutriate chemistry at selected stations at Reelfoot Lake, Tennessee  

USGS Publications Warehouse

To better-understand and predict the potential effect of dredging on water quality at Reelfoot Lake, chemical analyses were conducted on samples of lake water, bottom sediment, and elutriate water. Chemical analyses were conducted on samples of lake water, bottom sediment, and elutriate water collected at five stations in the lake during November 1988. Lake water was of the calcium magnesium bicarbonate type with an average dissolved-solids concentration of 120 milligrams per liter. Trace constituents were present in bottom sediments at concentrations representative of their average relative abundance in the earth?s crust. Elutriate waters prepared by mixing bottom sediment and lake water had suspended-solids concentrations as high as 2,000 milligrams per liter which exerted significant oxygen demand Trace constituents in the unfiltered elutriate waters were elevated with respect to lake water; elevated concentrations were attributable to the increased suspended-solids concentrations. Concentrations of total-recoverable copper, lead., and zinc in many elutriate waters exceeded U.S. Environmental Protection Agency?s water-quality criteria for the protection of freshwater aquatic life. The toxicity of elutriate waters, as measured by a 48-hour bioassay with Ceriodaphnia dubia, was low.

Broshears, R.E.

1991-01-01

234

Hydrothermal sediments are a source of water column Fe and Mn in the Bransfield Strait, Antarctica  

NASA Astrophysics Data System (ADS)

Short sediment cores were collected from ?1100 m water depth at the top of Hook Ridge, a submarine volcanic edifice in the Central Basin of the Bransfield Strait, Antarctica, to assess Fe and Mn supply to the water column. Low-temperature hydrothermal fluids advect through these sediments and, in places, subsurface H2S is present at high enough concentrations to support abundant Sclerolinum sp., an infaunal tubeworm that hosts symbiotic thiotrophic bacteria. The water column is fully oxic, and oxygen penetration depths at all sites are 2-5 cmbsf. Pore water Fe and Mn content is high within the subsurface ferruginous zone (max. 565 ?mol Fe L-1, >3-7 cmbsf)-14-18 times higher than values measured at a nearby, background site of equivalent water depth. Diffusion and advection of pore waters supply significant Fe and Mn to the surface sediment. Sequential extraction of the sediment demonstrates that there is a significant enrichment in a suite of reactive, authigenic Fe minerals in the upper 0-5 cm of sediment at one site characterised by weathered crusts at the seafloor. At a site with only minor authigenic mineral surface enrichment we infer that leakage of pore water Fe and Mn from the sediment leads to enriched total dissolvable Fe and Mn in bottom waters. An Eh sensor mounted on a towed package mapped a distinct Eh signature above this coring site which is dispersed over several km at the depth of Hook Ridge. We hypothesise that the main mechanism for Fe and Mn efflux from the sediment is breach of the surface oxic layer by the abundant Sclerolinum sp., along with episodic enhancements by physical mixing and resuspension of sediment in this dynamic volcanic environment. We propose that Hook Ridge sediments are an important source of Fe and Mn to the deep waters of the Central Basin in the Bransfield Strait, where concentrations are sustained by the benthic flux, and Fe is stabilised in the water column as either colloidal phases or ligand-bound dissolved species. Entrainment of this water mass into the Drake Passage and thereby the Antarctic Circumpolar Current could provide a significant metal source to this HNLC region of the Southern Ocean if mixing and upwelling occurs before removal of this metal pool to underlying sediments. Sediment-covered volcanic ridges are common within rifted margins and may play a previously overlooked role in the global Fe cycle.

Aquilina, Alfred; Homoky, William B.; Hawkes, Jeffrey A.; Lyons, Timothy W.; Mills, Rachel A.

2014-07-01

235

High performance in low-flow solar domestic hot water systems  

SciTech Connect

Low-flow solar hot water heating systems employ flow rates on the order of 1/5 to 1/10 of the conventional flow. Low-flow systems are of interest because the reduced flow rate allows smaller diameter tubing, which is less costly to install. Further, low-flow systems result in increased tank stratification. Lower collector inlet temperatures are achieved through stratification and the useful energy produced by the collector is increased. The disadvantage of low-flow systems is the collector heat removal factor decreases with decreasing flow rate. Many solar domestic hot water systems require an auxiliary electric source to operate a pump in order to circulate fluid through the solar collector. A photovoltaic driven pump can be used to replace the standard electrical pump. PV driven pumps provide an ideal means of controlling the flow rate, as pumps will only circulate fluid when there is sufficient radiation. Peak performance was always found to occur when the heat exchanger tank-side flow rate was approximately equal to the average load flow rate. For low collector-side flow rates, a small deviation from the optimum flow rate will dramatically effect system performance.

Dayan, M.

1997-12-31

236

Organochlorine Pesticides in Water, Sediment, Crops, and Human Fluids in a Farming Community in Ghana  

Microsoft Academic Search

A total of 208 samples of water, sediment, tomato crops, blood, and mothers' breast milk were collected from the environs\\u000a of Akumadan, a prominent vegetable-farming community in Ghana. The samples were analyzed for organochlorine (OC) pesticide\\u000a residues. Lindane and endosulfan were found in water and sediment, while other OC pesticide residues, such as hexachlorobenzene\\u000a (HCB), p,p?-DDE, and heptachlor epoxide, were

W. J. Ntow

2001-01-01

237

Differences between Betaproteobacterial Ammonia-Oxidizing Communities in Marine Sediments and Those in Overlying Water  

Microsoft Academic Search

To assess links between betaproteobacterial ammonia-oxidizing bacteria (AOB) in marine sediment and in overlying water, communities in Loch Duich, Scotland, were characterized by analysis of clone libraries and denaturant gradient gel electrophoresis of 16S rRNA gene fragments. Nitrosospira cluster 1-like sequences were isolated from both environments, but different sequence types dominated water and sediment samples. De- tailed phylogenetic analysis of

Thomas E. Freitag; James I. Prosser

2004-01-01

238

A shallow-water sedimentation model with friction and Coriolis: An existence theorem  

NASA Astrophysics Data System (ADS)

We present an existence theorem of a two-dimensional sedimentation model coupling a shallow water system with a sediment transport equation. The shallow water system includes Coriolis and friction terms. A Galerkin method is used to obtain a finite-dimensional problem which is solved using a Brouwer fixed point theorem. We prove that the limits of the resulting solution sequences satisfy the model equations.

Toumbou, Babacar; Le Roux, Daniel Y.; Sène, Abdou

239

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

240

Land application of domestic wastewater in Florida--statewide assessment of impact on ground-water quality  

USGS Publications Warehouse

In Florida domestic waste water is being applied to the land for disposal and reuse. State and Federal regulations favor land-application methods over other advanced waste water treatment practices. Despite the increasing use of this alternative technology, little is known about localized effects on groundwater quality. This report documents the extent of land-application practices in Florida and summarizes case study information on some of the more adequately monitored site throughout the State. More than 2,500 sites in Florida are permitted by the Department of Environmental Regulation for applying domestic waste water to the land. The majority (more than 1,700 sites), classified as infiltration ponds, are concentrated in central and southern Florida. More than 560 sites classified as drainfields, and more than 250 sites classified as irrigation sites, are located primarily in central Florida. An estimated 150 million gallons per day of domestic waste water, after required secondary treatment, are applied to Florida soils. Despite the large numbers of sites and the considerable volume of waste water utilized, little is known about potential impact on groundwater quality. At the few sites where observation wells have been drilled and local groundwater quality monitored, no significant deterioration of water quality has been detected. (USGS)

Franks, Bernard J.

1981-01-01

241

Pore water flow due to near-bed turbulence and associated solute transfer in a stream or lake sediment bed  

Microsoft Academic Search

A model of pore water flow induced by pressure fluctuations from a turbulent boundary layer flow over a permeable sediment bed is presented. The bed has a smooth or rough flat surface without bed forms. Pressure and velocity fluctuations that penetrate from the sediment\\/water interface into the sediment pore system and affect mass (solute) transfer are described as periodic in

Makoto Higashino; Jeffrey J. Clark; Heinz G. Stefan

2009-01-01

242

Effects of sediment transport and seepage direction on hydraulic properties at the sediment-water interface of hyporheic settings  

NASA Astrophysics Data System (ADS)

SummaryRelations between seepage flux and hydraulic properties are difficult to quantify in fluvial settings because of the difficulty in measuring these variables in situ. Tests conducted in a 1.5-m diameter by 1.5-m tall sediment-filled tank indicate that hydraulic gradient increased and hydraulic conductivity ( K) decreased following the onset of downward seepage but both parameters were little changed following the onset of upward seepage. Reductions in K during downward seepage were more pronounced when surface-water current was sufficient to mobilize sediment on the bed. Averaged ratios of K determined during upward seepage to K determined during downward seepage ( K up/K down) through a sand-and-gravel bed increased from 1.4 to 1.7 with increasing surface-water velocity, and decreased to slightly greater than 1 when the sediment bed became fully mobile. K up/K down for tests conducted with a silt veneer on the bed surface was greater than 2 for all but the fastest surface-water velocities. Substantial reductions in K also were associated with a silt floc that formed on the bed surface during and following test runs. Although the silt floc was typically less than 0.5 mm in thickness, most of the hydraulic gradient was distributed across this thin layer. K of the thin silt floc was reduced by two to three orders of magnitude relative to the underlying sediment. Directional bias in K and relation between K and surface-water velocity require the presence or absence of a layer of lower- K sediment at or near the bed surface, without which no reduction in K and corresponding increase in hydraulic gradient can occur at the bed surface. The lack of prior observation of the consistent bias in K associated with seepage direction is somewhat surprising given the numerous studies where K has been measured in fluvial settings, but may be explained by the small value of the bias relative to the typical uncertainty associated with field determinations of K. If shown to exist in field settings, this bias and its relation to fluvial processes will be relevant to many studies conducted in hyporheic settings that require determination of fluxes across the sediment-water interface.

Rosenberry, Donald O.; Pitlick, John

2009-07-01

243

Effects of sediment transport and seepage direction on hydraulic properties at the sediment-water interface of hyporheic settings  

USGS Publications Warehouse

Relations between seepage flux and hydraulic properties are difficult to quantify in fluvial settings because of the difficulty in measuring these variables in situ. Tests conducted in a 1.5-m diameter by 1.5-m tall sediment-filled tank indicate that hydraulic gradient increased and hydraulic conductivity (K) decreased following the onset of downward seepage but both parameters were little changed following the onset of upward seepage. Reductions in K during downward seepage were more pronounced when surface-water current was sufficient to mobilize sediment on the bed. Averaged ratios of K determined during upward seepage to K determined during downward seepage (Kup/Kdown) through a sand-and-gravel bed increased from 1.4 to 1.7 with increasing surface-water velocity, and decreased to slightly greater than 1 when the sediment bed became fully mobile. Kup/Kdown for tests conducted with a silt veneer on the bed surface was greater than 2 for all but the fastest surface-water velocities. Substantial reductions in K also were associated with a silt floc that formed on the bed surface during and following test runs. Although the silt floc was typically less than 0.5 mm in thickness, most of the hydraulic gradient was distributed across this thin layer. K of the thin silt floc was reduced by two to three orders of magnitude relative to the underlying sediment. Directional bias in K and relation between K and surface-water velocity require the presence or absence of a layer of lower-K sediment at or near the bed surface, without which no reduction in K and corresponding increase in hydraulic gradient can occur at the bed surface. The lack of prior observation of the consistent bias in K associated with seepage direction is somewhat surprising given the numerous studies where K has been measured in fluvial settings, but may be explained by the small value of the bias relative to the typical uncertainty associated with field determinations of K. If shown to exist in field settings, this bias and its relation to fluvial processes will be relevant to many studies conducted in hyporheic settings that require determination of fluxes across the sediment-water interface.

Rosenberry, D.O.; Pitlick, J.

2009-01-01

244

Percentage land use in the watershed determines the water and sediment quality of  

E-print Network

Percentage land use in the watershed determines the water and sediment quality of 22 marshes the relationship between land use and water quality. PC3, driven by soluble reactive phosphorus and nitrate nitrogen concentration in the water, was not correlated with land use. Concentrations of polycyclic

McMaster University

245

Analysis of national water pollution control policies: 2. Agricultural sediment control  

Microsoft Academic Search

Application of a national water network model permits an analysis of the likely affects of agricultural sediment control policies on the quality of the nation's waters. This analysis is believed superior to previous assessments based mainly on erosion estimates without accounting for the characteristics of the receiving water or the contribution of pollutants from nonagricultural activities. Specifically, while the earlier

Leonard P. Gianessi; Henry M. Peskin

1981-01-01

246

Heavy metals in water, sediment and tissues of Leuciscus cephalus from a stream in southwestern Turkey  

Microsoft Academic Search

Concentrations of heavy metals (Cd, Cr, Cu, Pb and Zn) were measured in water, bottom sediment and tissues (muscle and gills) of Leuciscus cephalus from the Dipsiz stream in the Yatagan basin (southwestern Turkey), the site of a thermal power plant. Results for levels in water were compared with national and international water quality guidelines, as well as literature values

Ahmet Demirak; Fevzi Yilmaz; A. Levent Tuna; Nedim Ozdemir

2006-01-01

247

Analysis of national water-pollution-control policies. 2. Agricultural sediment control  

Microsoft Academic Search

A national water network model is used to analyze the likely effects of agricultural sediment-control policies on the quality of the nation's waters. This analysis is believed superior to previous assessments based mainly on erosion estimates without accounting for the characteristics of the receiving water or the contribution of pollutants from nonagricultural activities. Specifically, while the earlier assessments concluded that

Leonard P. Gianessi; Henry M. Peskin

1981-01-01

248

Occurrence of perfluorinated compounds in the aquatic environment as found in science park effluent, river water, rainwater, sediments, and biotissues.  

PubMed

The current article maps perfluoroalkyl acids (PFAAs) contamination in the largest Science Park of Taiwan. The occurrence of ten target PFAAs in the effluent of an industrial wastewater treatment plant (IWWTP), its receiving rivers, rainwater, sediment, and the muscles and livers of fish was investigated. All target PFAAs were found in effluent of IWWTP, in which perfluorooctane sulfonate (PFOS) (6,930 ng/L), perfluorohexyl sulfonate (PFHxS) (2,662 ng/L) and perfluorooctanoic acid (PFOA) (3,298 ng/L) were the major constituents. Concentrations of PFBS and PFOS in the IWWTP downstream areas have exceeded safe concentration levels of avian and aquatic life, indicating a potential risk to wildlife in those areas. In sediment samples, predominant contaminants were PFOS (1.5-78 ng/g), PFOA (0.5-5.6 ng/g), and perfluorododecanoic acid (PFDoA) (nd-5.4 ng/g). In biological tissue samples, concentrations as high as 28,933 ng/g of PFOS were detected in tilapia and catfish liver samples. A positive correlation for log (C sediment/C water) and log (C tissue/C water) was found. The concentration and proportion (percentage of all PFAAs) of PFOS found in biotissue samples from the Keya River (which receives industrial wastewater) were found to be much greater (200 times) than those of samples from the Keelung River (which receives mainly domestic wastewater). These findings suggest that the receiving aquatic environments and, in turn, the human food chain can be significantly influenced by industrial discharges. PMID:24464397

Lin, Angela Yu-Chen; Panchangam, Sri Chandana; Tsai, Yu-Ting; Yu, Tsung-Hsien

2014-05-01

249

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

250

[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

251

Sediment-water distribution of contaminants of emerging concern in a mixed use watershed.  

PubMed

This study evaluated the occurrence and distribution of 15 contaminants of emerging concern (CECs) in stream water and sediments in the Zumbro River watershed in Minnesota and compared these with sub-watershed land uses. Sixty pairs of sediment and water samples were collected across all seasons from four stream sites for over two years and analyzed for selected personal care products, pesticides, human and veterinary medications, and phytoestrogens. Spatial and temporal analyses indicate that pharmaceuticals and personal care products (urban/residential CECs) are significantly elevated in water and/or sediment at sites with greater population density (>100people/km(2)) and percentage of developed land use (>8% of subwatershed area) than those with less population density and land area under development. Significant spatial variations of agricultural pesticides in water and sediment were detectable, even though all sites had a high percentage of agricultural land use. Seasonality in CEC concentration was observed in water but not in sediment, although sediment concentrations of three CECs did vary between years. Average measured non-equilibrium distribution coefficients exceeded equilibrium hydrophobic partitioning-based predictions for 5 of the 7 detected CECs by at least an order of magnitude. Agreement of measured and predicted distribution coefficients improved with increasing hydrophobicity and in-stream persistence. The more polar and degradable CECs showed greater variability in measured distributions across different sampling events. Our results confirm that CECs are present in urban and agricultural stream sediments, including those CECs that would typically be thought of as non-sorptive based on their log Kow values. These results and the observed patterns of sediment and water distributions augment existing information to improve prediction of CEC fate and transport, leading to more accurate assessments of exposure and risk to surface water ecosystems. PMID:25461092

Fairbairn, David J; Karpuzcu, M Ekrem; Arnold, William A; Barber, Brian L; Kaufenberg, Elizabeth F; Koskinen, William C; Novak, Paige J; Rice, Pamela J; Swackhamer, Deborah L

2015-02-01

252

Effect of sediment settling on controlling golden mussel invasion in water transfer project  

NASA Astrophysics Data System (ADS)

Inter-basin water transfer projects have been widely used to solve uneven distribution of water resources and water shortage in China. Along with the transferring of water resources, golden mussel (Limnoperna fortunei), the filter-collector macro-invertebrate species originating from southern China has also been inadvertently transferred to new aquatic environment, resulting in quick and uncontrolled spread of the species. The golden mussels are invasive by nature and endowed with a strong byssus for attaching onto their habitat, allowing them to easily invade natural and artificial aquatic systems, which was resulted in high-density golden mussel attachment that causes serious bio-fouling. Invasion and bio-fouling by golden mussels in water transfer systems has drawn attention widely because it has resulted in high resistance to water flow, corrosion of pipe walls and even clogging of tunnels, as well as causing water pollution and ecological imbalance in the regions that receive water infested with golden mussels. Field investigation was conducted along the East River, which is the main drinking water resource for Cantong province and Hongkong, China, to study the natural habitats of golden mussels. Surveys of water transfer tunnels which carry water from the East River to several big cities in Cantong province were done to study golden mussel invasion and attachment in tunnels. It is found that in the natural habitat, golden mussels mainly attach to bedrock and bank stones and solid surfaces facing upstream, while no golden mussels are attached on the surfaces facing downstream and suffering sediment deposition. In the water transfer tunnels, golden mussel attachment densities of 40,000 individuals/m2 mainly occurred on the portion of tunnel walls which face downwards and thus avoid sedimentation. An experiment was designed to study the effect of sediment settling on golden mussel attachment. The results showed that settling of fine sediment particles affects golden mussels by preventing them from filtering food and oxygen from water, and in this way killing them. The attachment density decreased with increased sediment deposition. Golden mussel density decreased by about 70-90% when the sedimentation rate increased by 3-6 times. Therefore, spraying with fine sediment or creating hyper-concentration of sediment water to treat golden mussels before they enter tunnels is recommended as an effective strategy for controlling golden mussel invasion and high-density bio-fouling. Key words: golden mussel invasion; bio-fouling; sediment settling; habitat; controlling strategy

Xu, Mengzhen; Wang, Zhaoyin; Bogen, Jim; Pan, Baozhu

2013-04-01

253

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...

254

Wave-induced advective transport below a rippled water-sediment interface  

NASA Astrophysics Data System (ADS)

The exchange between the water column and the sediment bed and the transport inside the permeable sediment layer are important processes in the cycles of chemical elements. In this paper we examine quantitatively the effects of modulations in the profile of the water-sediment interface on this exchange and on the advective transport inside the sediment bed. The flow field inside a sediment layer bounded between spatially periodic ripples on top and an impermeable bottom surface is modeled using Darcy's law. The forcing is due to progressive gravity waves in the water above. The results of two different models for the pressure variation imposed on the upper boundary are compared. The two pressure profiles are derived from potential flow theory and from a numerical solution to the Navier-Stokes equations for the oscillatory flow over a rippled bed. From an analytic solution to the two-dimensional model, the trajectories of pore water particles immediately below the ripple profile are found to be quite different from the simple elliptical pattern found below a flat bed. The shapes of these trajectories can be quite complicated and vary considerably both along the length of the ripple and over the depth of the sediment layer close to its surface. The total exchange across the water-sediment interface, averaged over one wave period, is significantly higher across a rippled interface than across a flat bed. This difference increases with increasing ripple slope and the strength of the wave motion, and it decreases with increasing thickness of the sediment layer relative to the length of the gravity wave. Since rippled bed forms are commonly found in coastal waters, the increase in the total exchange across a rippled water-sediment boundary can enhance the exchange of solutes due to "wave pumping." Immediately below the water-sediment interface, circulation cells with net advective transport over a wave period are found. Such net advection patterns can lead to spatial (in the horizontal direction) inhomogeneities of the vertical concentration (or temperature) profiles if the overlying water column and/or the sediment bed act(s) as source or sink. This gives a plausible physical mechanism to explain the spatial variations in vertical concentration profiles found in field measurements.

Shum, K. T.

1992-01-01

255

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

256

Arsenic Redistribution Between Sediments and Water Near a Highly Contaminated Source  

SciTech Connect

Mechanisms controlling arsenic partitioning between sediment, groundwater, porewaters, and surface waters were investigated at the Vineland Chemical Company Superfund site in southern New Jersey. Extensive inorganic and organic arsenic contamination at this site (historical total arsenic >10 000 {micro}g L{sup -1} or >130 {micro}M in groundwater) has spread downstream to the Blackwater Branch, Maurice River, and Union Lake. Stream discharge was measured in the Blackwater Branch, and water samples and sediment cores were obtained from both the stream and the lake. Porewaters and sediments were analyzed for arsenic speciation as well as total arsenic, iron, manganese, and sulfur, and they indicate that geochemical processes controlling mobility of arsenic were different in these two locations. Arsenic partitioning in the Blackwater Branch was consistent with arsenic primarily being controlled by sulfur, whereas in Union Lake, the data were consistent with arsenic being controlled largely by iron. Stream discharge and arsenic concentrations indicate that despite large-scale groundwater extraction and treatment, >99% of arsenic transport away from the site results from continued discharge of high arsenic groundwater to the stream, rather than remobilization of arsenic in stream sediments. Changing redox conditions would be expected to change arsenic retention on sediments. In sulfur-controlled stream sediments, more oxic conditions could oxidize arsenic-bearing sulfide minerals, thereby releasing arsenic to porewaters and streamwaters; in iron-controlled lake sediments, more reducing conditions could release arsenic from sediments via reductive dissolution of arsenic-bearing iron oxides.

Keimowitz,A.; Zheng, Y.; Chillrud, S.; Mailloux, B.; Bok Jung, H.; Stute, M.; Simpson, H.

2005-01-01

257

Diffusive Release of Uranium from Contaminated Sediments into Capillary Fringe Pore Water  

SciTech Connect

We investigated the dynamics of U release between pore water fractions, during river stage changes from two contaminated capillary fringe sediments. Samples were from 7.0 m and 7.6 m below ground surface (bgs) in the Hanford 300 area. Sediments were packed into columns and saturated with Hanford groundwater for three to 84 days. After specified times, > 48 µm radius (calculated) sediment pores were drained, followed by draining pores to 15 µm radius. U release in the first two weeks was similar between sediments and pore sizes with a range of 4.4 to 5.6 µM U in the 14 day sample. The 7.0 m bgs sediment U declined in the larger pores to 0.22 µM at day 84, whereas the small pores released U to 6.7 µM at day 84. The 7.6 m bgs sediment released 1.4 µM on day 84, in the large pores, but continuously released U from the smaller pores (13.2 uM on day 84). The continuous release of U has resulted in a diffusion gradient from the smaller to larger pores. The observed differences in U pore-water concentrations between the two sediment samples were attributed to co-precipitation of U with carbonates. A mineral phase in the sediments was also identified as an U-carbonate species, similar to rutherfordine [UO2(CO3)].

Rod, Kenton A.; Wellman, Dawn M.; Flury, Markus; Pierce, Eric M.; Harsh, James B.

2012-09-13

258

A conceptual model for river water and sediment dispersal in the Santa Barbara Channel, California  

USGS Publications Warehouse

The ephemeral Santa Clara River delivers large amounts of freshwater and sediment to the eastern Santa Barbara Channel during brief, episodic discharge events. This discharge into the channel was characterized here with shipboard measurements during floods of 1997 and 1998. Within approximately 1-km of the river mouth, the river discharge quickly stratifies into a freshened, turbid surface plume and a bottom nephloid layer. Observations immediately off the Santa Clara River mouth on a peak day of river discharge revealed that sediment rapidly settled from the freshened surface waters, as suspended sediment in the freshened surface plume contained only ???6% of the sediment mass expected if the sediment mixed conservatively. On the two subsequent days the reduction of sediment mass in the surface plume continued at ???50% per day. These observations suggest that river sediment undergoes rapid initial settling within ???1-km of the river mouth, followed by somewhat slower rates of settling. Although we did not measure sedimentation or bottom boundary layer processes, our mass balance results suggest that almost all of the river sediment either escapes along or deposits upon the inner shelf seabed.

Warrick, J.A.; Mertes, L.A.K.; Washburn, L.; Siegel, D.A.

2004-01-01

259

Dynamic existence of waterborne pathogens within river sediment compartments. Implications for water quality regulatory affairs.  

PubMed

The transport and fate of indicator E. coli and Salmonella are shown to be highly influenced by their relationship with flocculated suspended and bed sediment particles. Flocs were found to dominate the suspended sediment load and have the effect of increasing the downward flux of the sediment to the river bed. Bacteria counts were consistently higher within sediment compartments (suspended and bed) than for the water alone, with the bed sediment found to represent a possible reservoir of pathogens for subsequent remobilization and transport to potentially high risk areas. The mechanism of microbial attachment and entrapment within the sediment was strongly linked to the EPS fibrils secreted by the biological consortium of the aquatic system. It is suggested that the sediment/pathogen relationship should be of concern to public health officials because of its potential effects on pathogen source fate and effect with implications on public health risk assessment. Current standard sampling strategies, however, are based on an assumption that bacteria are entirely planktonic and do not account for the potentially significant concentration of bacteria from the sediment compartments. The lack of understanding around pathogen/sediment associations may lead to an inaccurate estimate of public health risk, and, as such, possible modification of sampling strategies to reflect this association may be warranted. PMID:19368165

Droppo, Ian G; Liss, Steven N; Williams, Declan; Nelson, Tara; Jaskot, Chris; Trapp, Brian

2009-03-15

260

Assessing the stability of phosphorus in lake sediments amended with water treatment residuals.  

PubMed

The reuse of drinking water treatment residuals (WTRs) to immobilize phosphorus (P) in sediments is a novel application for lake restoration. The recycling of WTRs is beneficial from both environmental and economic standpoints. This work assessed the stability of P in sediments found in Lake Taihu and Lake Baiyangdian before and after being amended with WTRs. The results indicated that WTRs had similar effects on the stability of P in each of the lake's sediments. WTRs can significantly reduce the P desorption potential of the sediments at pH values less than 11. WTRs can also inhibit the competitive adsorption of SiO4(2-) with P. Compared with the raw sediments, the organic matter in the sediments, ion strength and anaerobic conditions presented minor undesirable effects on the stability of P in the WTRs-amended sediments. Moreover, WTRs can increase the P adsorption rate and capacity of the sediments. Overall, these results demonstrated that WTRs can make P more stable in lake sediments under various conditions. PMID:23542229

Wang, Changhui; Bai, Leilei; Pei, Yuansheng

2013-06-15

261

Modeling Metals Transport and Sediment/Water Interactions in a Mining Impacted Mountain Stream  

NASA Astrophysics Data System (ADS)

The U.S. Environmental Protection Agency (USEPA) Water Quality Analysis Simulation Program (WASP5) was used to model the transport and sediment/water interactions of metals under low flow, steady state conditions in Tenmile Creek, a mountain stream supplying drinking water to the City of Helena, Montana, impacted by numerous abandoned hard rock mines. The model was calibrated for base flow using data collected by USEPA and validated using data from the U.S. Geological Survey (USGS) for higher flows. It was used to assess metals loadings and losses, exceedances of Montana State water quality standards, metals interactions in stream water and bed sediment, uncertainty in fate and transport processes and model parameters, and effectiveness of remedial alternatives that include leaving contaminated sediment in the stream. Results indicated that during base flow, adits and point sources contribute significant metals loadings to the stream, but that shallow ground water and bed sediment also contribute metals in some key locations. Losses from the water column occur in some areas, primarily due to adsorption and precipitation onto bed sediments. Some uncertainty exists in the metal partition coefficients associated with sediment, significance of precipitation reactions, and in the specific locations of unidentified sources and losses of metals. Standards exceedances are widespread throughout the stream, but the model showed that remediation of point sources and mine waste near water courses can help improve water quality. Model results also indicate, however, that alteration of the water supply scheme and increasing base flow will probably be required to meet all water quality standards.

Caruso, Brian S.

2004-12-01

262

Recent changes of water discharge and sediment load in the Zhujiang (Pearl River) Basin, China  

NASA Astrophysics Data System (ADS)

The paper is concerned with identifying changes in the time series of water and sediment discharge of the Zhujiang (Pearl River), China. The gradual trend test (Mann-Kendall test), and abrupt change test (Pettitt test), have been employed on annual water discharge and sediment load series (from the 1950s-2004) at nine stations in the main channels and main tributaries of the Zhujiang. Both the Mann-Kendall and Pettitt tests indicate that water discharge at all stations in the Zhujiang Basin showed no significant trend or abrupt shift. Annual water discharges are mainly influenced by precipitation variability, while the construction of reservoirs/dams in the Zhujiang Basin had little influence on water discharge. Sediment load, however, showed significant decreasing trends at some stations in the main channel of the Xijiang and Dongjiang. More stations have seen significantly decreasing trends since the 1990s. The decreasing sediment load in the Zhujiang reflects the impacts of reservoir construction in the basin. In contrast, the Liujiang, the second largest tributary of the Xijiang, has experienced a significant upward shift of sediment load around 1991 likely caused by exacerbated rock desertification in the karst regions. The annual sediment load from the Zhujiang (excluding the delta region) to the estuary has declined from 80.4 × 10 6 t averaged for the period 1957-1995 to 54.0 × 10 6 t for the period 1996-2004. More specifically, the sediment load declined steadily since the early 1990s so that in 2004 it was about one-third of the mean level of pre-90s. Water discharge and sediment load of the Zhujiang would be more affected by human activities in the future with the further reservoir developments, especially the completion of the Datengxia hydroelectric project, and an intensification of the afforestation policy in the drainage basin.

Zhang, Shurong; Lu, Xi Xi; Higgitt, David L.; Chen, Chen-Tung Arthur; Han, Jingtai; Sun, Huiguo

2008-02-01

263

Sequestration of priority pollutant PAHs from sediment pore water employing semipermeable membrane devices  

USGS Publications Warehouse

Semipermeable membrane devices (SPMDs) were employed to sample sediment pore water in static exposure studies under controlled laboratory conditions using (control pond and formulated) sediments fortified with 15 priority pollutant polycyclic aromatic hydrocarbons (PPPAHs). The sediment fortification level of 750 ng/g was selected on the basis of what might be detected in a sediment sample from a contaminated area. The sampling interval consisted of 0, 4, 7, 14, and 28 days for each study. The analytical methodologies, as well as the extraction and sample cleanup procedures used in the isolation, characterization, and quantitation of 15 PPPAHs at different fortification levels in SPMDs, water, and sediment were reported previously (Williamson, M.S. Thesis, University of Missouri - Columbia, USA; Williamson et al., Chemosphere (This issue - PII: S0045-6535(02)00394-6)) and used for this project. Average (mean) extraction recoveries for each PPPAH congener in each matrix are reported and discussed. No procedural blank extracts (controls) were found to contain any PPPAH residues above the method quantitation limit, therefore, no matrix interferences were detected. The focus of this publication is to demonstrate the ability to sequester environmental contaminants, specifically PPPAHs, from sediment pore water using SPMDs and two different types of fortified sediment.

Williamson, K.S.; Petty, J.D.; Huckins, J.N.; Lebo, J.A.; Kaiser, E.M.

2002-01-01

264

A review of surface-water sediment fractions and their interactions with persistent manmade organic compounds  

USGS Publications Warehouse

This paper reviews the suspended and surficial sediment fractions and their interactions with manmade organic compounds. The objective of this review is to isolate and describe those contaminant and sediment properties that contribute to the persistence of organic compounds in surface-water systems. Most persistent, nonionic organic contaminants, such as the chlorinated insecticides and polychlorinated biphenyls (PCBs), are characterized by low water solubilities and high octanol-water partition coefficients. Consequently, sorptive interactions are the primary transformation processes that control their environmental behavior. For nonionic organic compounds, sorption is primarily attributed to the partitioning of an organic contaminant between a water phase and an organic phase. Partitioning processes play a central role in the uptake and release of contaminants by sediment organic matter and in the bioconcentration of contaminants by aquatic organisms. Chemically isolated sediment fractions show that organic matter is the primary determinant of the sorptive capacity exhibited by sediment. Humic substances, as dissolved organic matter, contribute a number of functions to the processes cycling organic contaminants. They alter the rate of transformation of contaminants, enhance apparent water solubility, and increase the carrying capacity of the water column beyond the solubility limits of the contaminant. As a component of sediment particles, humic substances, through sorptive interactions, serve as vectors for the hydrodynamic transport of organic contaminants. The capabilities of the humic substances stem in part from their polyfunctional chemical composition and also from their ability to exist in solution as dissolved species, flocculated aggregates, surface coatings, and colloidal organomineral and organometal complexes. The transport properties of manmade organic compounds have been investigated by field studies and laboratory experiments that examine the sorption of contaminants by different sediment size fractions. Field studies indicate that organic contaminants tend to sorb more to fine-grained sediment, and this correlates significantly with sediment organic matter content. Laboratory experiments have extended the field studies to a wider spectrum of natural particulates and anthropogenic compounds. Quantitation of isotherm results allows the comparison of different sediment sorbents as well as the estimation of field partition coefficients from laboratory-measured sediment and contaminant properties. Detailed analyses made on the basis of particle-size classes show that all sediment fractions need to be considered in evaluating the fate and distribution of manmade organic compounds. This conclusion is based on observations from field studies and on the variety of natural organic sorbents that demonstrate sorptive capabilities in laboratory isotherm experiments.

Witkowski, P.J.; Smith, J.A.; Fusillo, T.V.; Chiou, C.T.

1987-01-01

265

Ecotoxicological characterisation of sedimentation in the Kis-Balaton Water Protection System.  

PubMed

The main function of the Kis-Balaton Water Protection System is to retain nutrients and total suspended solids, thus protecting the water quality of Lake Balaton. In this paper, the toxic nature of the sediment in the 2nd reservoir of the KBWPS has been characterised, using a battery of tests: Vibrio fischeri acute bioassay on whole sediment samples, and V. fischeri bioassay on pore water and elutriate samples. The latest version of the V. fischeri bioluminescence inhibition was applied, the Flash assay which uses a kinetic mode and is able to detect the toxicity of solid, turbid/coloured samples. Whole sediment toxicity showed a clear spatial distribution of toxicity, in parallel with elutriate toxicity. However, no pore water toxicity was detected, leading to the conclusion that contaminants are not water soluble. PMID:22695524

Paulovits, G; Kováts, Nóra; Acs, Á; Ferincz, Á; Kovács, Anikó; Kakasi, B; Nagy, Sz; Kiss, Gy

2012-06-01

266

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

267

Microscale Modelling of Water and Gas-Water Flows in Subsea Sand Sediment  

NASA Astrophysics Data System (ADS)

Methane hydrate is a promising energy resource in the near future. Its production is a current hot topic and flow of methane gas with water in sediment sand layer is very important to predict the production rate. In this study, permeability of microscale sand layer was numerically simulated by a three-dimensional lattice Boltzmann method. Shapes of real sands were extracted by series expansion of spherical harmonics using CT-scan images of real subsea core samples. These extracted sands were located in a cubic lattice domain by a simulated annealing method to fit to given porosities. Pressure difference was imposed at the both end faces of the domain to flow water and methane gas. By this simulation, permeability of water phase and water-gas two-phase flow were analysed and compared well with existing models. This work was financially supported by Japan's Methane Hydrate R&D Program planned by Ministry of Economy, Trade and Industry (METI). 3D image of an extracted frame-sand grain Distribution of gas and water phases in computational domain for Sw=0.80

Sato, T.; Sugita, T.; Hirabayashi, S.; Nagao, J.; Jin, Y.; Kiyono, F.

2009-12-01

268

Analytical Methods for Measuring Mercury in Water, Sediment and Biota  

SciTech Connect

Mercury (Hg) exists in a large number of physical and chemical forms with a wide range of properties. Conversion between these different forms provides the basis for mercury's complex distribution pattern in local and global cycles and for its biological enrichment and effects. Since the 1960’s, the growing awareness of environmental mercury pollution has stimulated the development of more accurate, precise and efficient methods of determining mercury and its compounds in a wide variety of matrices. During recent years new analytical techniques have become available that have contributed significantly to the understanding of mercury chemistry in natural systems. In particular, these include ultra sensitive and specific analytical equipment and contamination-free methodologies. These improvements allow for the determination of total mercury as well as major species of mercury to be made in water, sediments and soils, and biota. Analytical methods are selected depending on the nature of the sample, the concentration levels of mercury, and what species or fraction is to be quantified. The terms “speciation” and “fractionation” in analytical chemistry were addressed by the International Union for Pure and Applied Chemistry (IUPAC) which published guidelines (Templeton et al., 2000) or recommendations for the definition of speciation analysis. "Speciation analysis is the analytical activity of identifying and/or measuring the quantities of one or more individual chemical species in a sample. The chemical species are specific forms of an element defined as to isotopic composition, electronic or oxidation state, and/or complex or molecular structure. The speciation of an element is the distribution of an element amongst defined chemical species in a system. In case that it is not possible to determine the concentration of the different individual chemical species that sum up the total concentration of an element in a given matrix, meaning it is impossible to determine the speciation, it is a useful practice to do fractionation instead. Fractionation is the process of classification of an analyte or a group of analytes from a certain sample according to physical (e.g. size, solubility) or chemical (e.g. bonding, reactivity) properties."

Lasorsa, Brenda K.; Gill, Gary A.; Horvat, Milena

2012-06-07

269

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

270

Analysis of Nitrogen Pollution Load by Domestic Waste Water Treatment in the Tedori River Alluvial Fan Areas  

NASA Astrophysics Data System (ADS)

An evaluation of the environment nitrogen pollution load with regard to domestic waste water treatment on the Tedori River Alluvial Fan Areas was conducted. The literature-based water quality data collected before and after the treatment and the basic outflow pollution unit was determined for the several water treatment systems. Next these data were applied for the entire alluvial fan areas resulting in an estimated total nitrogen pollution load of as 186 ton/year. 58% of the total nitrogen pollution load was estimated to be from the private residences that were not connected to the public sewage system (connecting ratio 90.5%) which thus had relation to the pollution of groundwater and water quality in the drainage canal in the region under consideration. The nitrogen pollution load was higher in the urban area more than the rural. The rural domestic waste water system accounted for about 17.9% of the total pollution load, which carried a high probability of groundwater pollution because of seepage or percolation. The pollution load from the direct flow of the public sewage treatment water to the middle stream of the Tedori River, together with the water from small companies and untreated water from local family dwellings made up about 3-10% of total pollution.

Maruyama, Toshisuke; Noto, Fumikazu; Takahashi, Tsuyoshi; Tsuchihara, Takeo; Tanaka, Tadashi

271

Energy use and domestic hot water consumption - Phase 1. Final report  

SciTech Connect

New York State Energy Research & Development Authority has sponsored a project to develop comprehensive operating data on combined domestic hot water (DHW) and heating systems to be used in system design and specifications. The new, more precise DHW flow data (broken down on a per capita basis) result in a better foundation for sizing decisions. Thirty New York City multifamily buildings with combined steam heating and DHW plants were instrumented to monitor apartment, outdoor, boiler and DHW temperatures, and burner on-off times. In nine buildings, which had been upgraded, additional data collected were: stack temperature, DHW flow in 15-minute increments, oil and boiler make-up water flows, and DHW temperature before and after the mixing valve and on the return line. The data set collected for 14 months amounts to a data base of over 110 megabytes. This report presents DHW demand patterns, seasonal variations, weekday vs. weekend consumption, consumption vs. occupancy levels, coincidence of 15-, 60-, 120-, and 180- minute demand periods, and average vs. peak demand levels, as well as figures for energy to generate DHW. The format of guidelines presented in this report differs from those currently in use. The {open_quotes}Low - Medium - High{close_quotes} (LMH) users set of guidelines provide a range, rather than a specific, singular gallonage standard. By providing LMH tables and guidelines for their application the design engineer or contractor can then use these as a tool from which to select the appropriate level that matches the site being served. Values are presented for both New York sizing guidelines (developed from this study), as well as a set of {open_quote}National{close_quote} figures (derived from a compilation of studies conducted in other cities). The LMH approach and {open_quote}National{close_quote} guidelines were adopted for inclusion in the 1995 ASHRAE Handbook revision.

Goldner, F.S. [Energy Management & Research Associates, Brooklyn, NY (United States)

1994-11-01

272

Microbial transformations of arsenic: Mobilization from glauconitic sediments to water  

USGS Publications Warehouse

In the Inner Coastal Plain of New Jersey, arsenic (As) is released from glauconitic sediment to carbon- and nutrient-rich shallow groundwater. This As-rich groundwater discharges to a major area stream. We hypothesize that microbes play an active role in the mobilization of As from glauconitic subsurface sediments into groundwater in the Inner Coastal Plain of New Jersey. We have examined the potential impact of microbial activity on the mobilization of arsenic from subsurface sediments into the groundwater at a site on Crosswicks Creek in southern New Jersey. The As contents of sediments 33–90 cm below the streambed were found to range from 15 to 26.4 mg/kg, with siderite forming at depth. Groundwater beneath the streambed contains As at concentrations up to 89 ?g/L. Microcosms developed from site sediments released 23 ?g/L of As, and active microbial reduction of As(V) was observed in microcosms developed from site groundwater. DNA extracted from site sediments was amplified with primers for the 16S rRNA gene and the arsenate respiratory reductase gene, arrA, and indicated the presence of a diverse anaerobic microbial community, as well as the presence of potential arsenic-reducing bacteria. In addition, high iron (Fe) concentrations in groundwater and the presence of iron-reducing microbial genera suggests that Fe reduction in minerals may provide an additional mechanism for release of associated As, while arsenic-reducing microorganisms may serve to enhance the mobility of As in groundwater at this site.

Mumford, Adam C.; Barringer, Julia L.; Benzel, William M.; Reilly, Pamela A.; Young, L.Y.

2012-01-01

273

Grazing Land Management Strongly Controls Water Quality, Sediment and Channel Dynamics in Tallgrass Prairie Headwater Networks  

NASA Astrophysics Data System (ADS)

In the prairie remnants of North America, watershed sediment regimes are heavily influenced by livestock grazing practices. Despite dramatic declines in stream water quality and ecosystem function concomitant with increasing gazing pressures, there have been no studies to quantitatively assess the relationship between various grazing treatments and sediment production in natural grassland ecosystems. In this study, we evaluate suspended sediment transport and channel morphology in the Flint Hills physiographic province using a paired whole-watershed approach, including 2 replicates of high density cattle grazing, 2 replicates of low density cattle grazing, 3 replicates of bison grazing and 3 replicates of no grazing. As expected, results demonstrate that cattle grazing operations increase e-coli, sediment concentrations and increase channel width. However, no significant differences in e-coli, suspended sediment dynamics or channel geomorphology were found between bison grazed and ungrazed watersheds.

Grudzinski, B. G.; Daniels, M. D.

2013-12-01

274

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

275

Radon 222 distribution and transport across the sediment-water interface in the Hudson River estuary  

SciTech Connect

Radon 222 concentrations in waters of the Hudson River estuary show little consistent vertical, axial, or seasonal variation. The median of 106 summer measurements is 1.43 +- 0.25 dpm/1, and the median of 17 winter measurements is 1.30 +- 0.35 dpm/1. A budget is constructed for the water column which balances the rate of radon input against the rate of radon loss for two regions, one of which is broad and shallow and the other narrow and deep. The primary supply of radon for these two regions is from the sediments (75--90%), with minor inputs from radium 226 decay in the water column, stream runoff, and tidal pumping of groundwater. Loss of radon occurs by evasion to the atmosphere and decay in the water column in roughly equal amounts. The activity of mobile radon in sediments (per wet sediment volume) is 0.33 +- 0.10 dpm/cm/sup 3/ in the broad, shallow area of the estuary and 0.42 +- 0.11 dpm/cm/sup 3/ in the narrow, deep reach immediately upstream. When these value are used, the flux supplied by molecular diffusion is approximately 40% of the total input. Constant physical stirring of the upper few centimeters of sediments by bottom currents over large areas and stochastic reworking to somewhat greater depth in localized sediment deposits appear to be primarily responsible for augmenting the flux from sediments provided by molecular diffusion.

Hammond, D.E.; Simpson, H.J.; Mathieu, G.

1977-09-20

276

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

277

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

278

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

279

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...

280

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

281

Analysis of pesticides in surface water and sediment from Yolo Bypass, California, 2004-2005  

USGS Publications Warehouse

Inputs to the Yolo Bypass are potential sources of pesticides that could impact critical life stages of native fish. To assess the direct inputs during inundation, pesticide concentrations were analyzed in water, in suspended and bed-sediment samples collected from six source watersheds to the Yolo Bypass, and from three sites within the Bypass in 2004 and 2005. Water samples were collected in February 2004 from the six input sites to the Bypass during the first flood event of the year representing pesticide inputs during high-flow events. Samples were also collected along a transect across the Bypass in early March 2004 and from three sites within the Bypass in the spring of 2004 under low-flow conditions. Low-flow data were used to understand potential pesticide contamination and its effects on native fish if water from these areas were used to flood the Bypass in dry years. To assess loads of pesticides to the Bypass associated with suspended sediments, large-volume water samples were collected during high flows in 2004 and 2005 from three sites, whereas bed sediments were collected from six sites in the fall of 2004 during the dry season. Thirteen current-use pesticides were detected in surface water samples collected during the study. The highest pesticide concentrations detected at the input sites to the Bypass corresponded to the first high-flow event of the year. The highest pesticide concentrations at the two sites sampled within the Bypass during the early spring were detected in mid-April following a major flood event as the water began to subside. The pesticides detected and their concentrations in the surface waters varied by site; however, hexazinone and simazine were detected at all sites and at some of the highest concentrations. Thirteen current-use pesticides and three organochlorine insecticides were detected in bed and suspended sediments collected in 2004 and 2005. The pesticides detected and their concentrations varied by site and sediment sample type. Trifluralin, p,p'-DDE, and p,p'-DDT were highest in the bed sediments, whereas oxyfluorfen and thiobencarb were highest in the suspended sediments. With the exception of the three organochlorine insecticides, suspended sediments had higher pesticide concentrations compared with bed sediments, indicating the potential for pesticide transport throughout the Bypass, especially during high-flow events. Understanding the distribution of pesticides between the water and sediment is needed to assess fate and transport within the Bypass and to evaluate the potential effects on native fish.

Smalling, Kelly L.; Orlando, James L.; Kuivila, Kathryn M.

2005-01-01

282

Exchange of nutrients across the sediment-water interface in intertidal ria systems (SW Europe)  

NASA Astrophysics Data System (ADS)

Concentrations of nitrate, nitrite, ammonium, phosphate and silicate were determined in river water, tidal water that floods the intertidal sediment (flooding water) and pore water of those sediments in the Northern Galician Rias of Ortigueira and Viveiro (NW Iberian Peninsula). The field surveys were done in the productive seasons of spring and summer 2008. Short-sediment cores and tidal flooding water were sampled at the intertidal area during the first 20 min that the tide inundates the sampling site. Nutrient fluxes of rivers (Lourido and Landro) flowing into the rias were in the order of H4SiO4 > NO3- > NH4+ > HPO42 Nutrients input from those rivers were low relative to the nutrient discharge of the entire coastal area. Striking changes of nutrient concentrations in flooding and pore waters of intertidal sediments were observed in the short periods of tidal inundation. Nutrient fluxes driven by molecular diffusion and tide-induced transport across the sediment-water interface were quantified and compared to the nutrient river contribution. Diffusive fluxes ranged from 9.3 to 13.7 nmol·cm- 2·d- 1 for nitrate and nitrite, - 1.32 to 30.1 nmol·cm- 2·d- 1 for ammonium, - 0.01 to 0.49 nmol·cm- 2·d- 1 for phosphate, and - 13.2 to 0.2 nmol·cm- 2·d- 1 for silicate. Tide-induced transport always exceeded diffusive fluxes, with differences reaching up to four orders of magnitude for silicate. The overall results of this study emphasize the relevance of tidal water movement in promoting the sediment-water exchange of nutrients in intertidal sub-ecosystems.

Ospina-Alvarez, N.; Caetano, M.; Vale, C.; Santos-Echeandía, J.; Bernárdez, P.; Prego, R.

2014-01-01

283

Mercury and methylmercury contents in mine-waste calcine, water, and sediment collected from the Palawan Quicksilver mine, Philippines  

USGS Publications Warehouse

The Palawan Quicksilver mine, Philippines, produced about 2,900 t of mercury during mining of cinnabar ore from 1953 to 1976. More than 2,000,000 t of mine-waste calcines (retorted ore) were produced during mining, much of which were used to construct a jetty in nearby Honda Bay. Since 1995, high Hg contents have been found in several people living near the mine, and 21 of these people were treated for mercury poisoning. Samples of mine-waste calcine contain high total Hg concentrations ranging from 43-660 ??g/g, whereas total Hg concentrations in sediment samples collected from a mine pit lake and local stream vary from 3.7-400 ??g/g. Mine water flowing through the calcines is acidic, pH 3.1-4.3, and total Hg concentrations ranging from 18-31 ??g/l in this water significantly exceed the 1.0-??g/l drinking water standard for Hg recommended by the World Health Organization (WHO). Total Hg contents are generally lower in water samples collected from surrounding domestic wells, the mine pit lake, Honda Bay, and the nearby stream, varying from 0.008-1.4 ??g/l. Methylmercury concentrations in water draining mine calcines range from <0.02-1.4 ng/l, but methylmercury is highest in the pit lake water, ranging from 1.7-3.1 ng/l. Mercury methylation at the Palawan mine is similar to or higher than that found in other mercury mines worldwide. Much of the methylmercury generated in Palawan mine-waste calcines and those in Honda Bay is transferred to water, and then to marine fish and seafood. A food source pathway of Hg to humans is most likely in this coastal, high fish-consuming population.

Gray, J.E.; Greaves, I.A.; Bustos, D.M.; Krabbenhoft, D.P.

2003-01-01

284

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

2011-06-01

285

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...

286

BENTHIC INVERTEBRATE BIOASSAYS WITH TOXIC SEDIMENT AND PORE WATER  

EPA Science Inventory

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. he assays studied were: (a) Microtox, a 15-min assay of Photobacterium...

287

ATRAZINE DESORPTION KINETICS FROM A FRESH-WATER SEDIMENT  

EPA Science Inventory

Research has shown that the sorption and desorption of neutral organic compounds to soils and sediments occurs in two stages, with an initial rapid sorption/desorption phase (usually less than an hour) followed by a slower phase that can last for several months to years for very ...

288

In Vitro Cyclooxygenase Inhibition Assay for Evaluating Ecotoxicity of the Surface Water and Domestic Wastewater in the Tone Canal, Japan  

Microsoft Academic Search

Cyclooxygenase (COX) plays an important role in eicosanoid metabolism. Nonsteroidal anti-inflammatory drugs (NSAIDs) function\\u000a as COX inhibitors and are frequently detected in the aquatic environment. Here, we measured the in vitro COX-inhibiting activity\\u000a of the surface water and domestic wastewater in the Tone Canal, Japan. The concentrations of several NSAIDs in the some samples\\u000a were also determined using gas chromatography–tandem

Iwaki Nishi; Takaaki Komuro; Tsuyoshi Kawakami; Sukeo Onodera

2010-01-01

289

Effects of plumbing attachments on heat losses from solar domestic hot water storage tanks. Final report, Part 2  

Microsoft Academic Search

The Solar Rating and Certification Corporation (SRCC) has established a standardized methodology for determining the performance rating of the Solar Domestic Hot Water (SDHW) systems it certifies under OG-300. Measured performance data for the solar collector component(s) of the system are used along with numerical models for the balance of the system to calculate the system`s thermal performance under a

J. Song; B. D. Wood; L. J. Ji

1998-01-01

290

Analysis of national water pollution control policies: 2. Agricultural sediment control  

NASA Astrophysics Data System (ADS)

Application of a national water network model permits an analysis of the likely affects of agricultural sediment control policies on the quality of the nation's waters. This analysis is believed superior to previous assessments based mainly on erosion estimates without accounting for the characteristics of the receiving water or the contribution of pollutants from nonagricultural activities. Specifically, while the earlier assessments concluded that agriculture-related pollution problems are widespread and ubiquitous, this analysis concludes that it is probably more efficient to focus sediment-related pollution control policies on about one third of the nation's agricultural regions.

Gianessi, Leonard P.; Peskin, Henry M.

1981-08-01

291

Laboratory measurements of physical, chemical, and optical characteristics of Lake Chicot sediment waters  

NASA Technical Reports Server (NTRS)

Reflectance, chromaticity, diffuse attenuation, beam attenuation, and several other physical and chemical properties were measured for various water mixtures of lake bottom sediment. Mixture concentrations range from 5 ppm to 700 ppm by weight of total suspended solids in filtered deionized tap water. Upwelled reflectance is a nonlinear function of remote sensing wave lengths. Near-infrared wavelengths are useful for monitoring highly turbid waters with sediment concentrations above 100 ppm. It is found that both visible and near infrared wavelengths, beam attenuation correlates well with total suspended solids ranging over two orders of magnitude.

Witte, W. G.; Whitlock, C. H.; Usry, J. W.; Morris, W. D.; Gurganus, E. A.

1981-01-01

292

Human and climate impact on global riverine water and sediment fluxes - a distributed analysis  

NASA Astrophysics Data System (ADS)

Understanding riverine water and sediment dynamics is an important undertaking for both socially-relevant issues such as agriculture, water security and infrastructure management and for scientific analysis of climate, landscapes, river ecology, oceanography and other disciplines. Providing good quantitative and predictive tools in therefore timely particularly in light of predicted climate and landuse changes. The intensity and dynamics between man-made and climatic factors vary widely across the globe and are therefore hard to predict. Using sophisticated numerical models is therefore warranted. Here we use a distributed global riverine sediment and water discharge model (WBMsed) to simulate human and climate effect on our planet's large rivers.

Cohen, S.; Kettner, A.; Syvitski, J. P.

2013-05-01

293

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

2013-04-01

294

Organic matter diagenesis in shallow water carbonate sediments  

NASA Astrophysics Data System (ADS)

Muddy carbonate deposits near the Dry Tortugas, Florida, are characterized by high organic carbon remineralization rates. However, approximately half of the total sedimentary organic matter potentially supporting remineralization is occluded in CaCO 3 minerals (intracrystalline). While a portion of nonintracrystalline organic matter appears to cycle rapidly, intracrystalline organic matter has an approximately constant concentration with depth, suggesting that as long as its protective mineral matrix is intact, it is not readily remineralized. Organic matter in excess of intracrystalline organic matter that is preserved may have a variety of mineral associations (e.g., intercrystalline, adsorbed or detrital). In surface sediment, aspartic acid contributed ˜22 mole % and ˜50 mole % to nonintracrystalline and intracrystalline pools, respectively. In deeper sediment (1.6-1.7m), the composition of hydrolyzable amino acids in both pools was similar (aspartic acid ˜40 mole %). Like amino acids, intracrystalline and nonintracrystalline fatty acids have different compositions in surface sediments, but are indistinguishable at depth. These data suggest that preserved organic matter in the nonintracrystalline pool is stabilized by its interactions with CaCO 3. Neutral lipids are present in very low abundances in the intracrystalline pool and are extensively degraded in both the intracrystalline and nonintracrystalline pools, suggesting that mineral interactions do not protect these compounds from degradation. The presence of chlorophyll- a, but absence of phytol, in the intracrystalline lipid pool demonstrates that chloropigments are present only in the nonintracrystalline pool. Sedimentary chloropigments decrease with depth at similar rates in Dry Tortugas sediments as found in alumino-silicate sediments from the Long Island Sound, suggesting that chloropigment degradation is largely unaffected by mineral interactions. Overall, however, inclusion and protection of organic matter by biominerals is a major pathway for organic matter preservation in this low-organic carbon, biomineral-rich regime.

Ingalls, Anitra E.; Aller, Robert C.; Lee, Cindy; Wakeham, Stuart G.

2004-11-01

295

Concentrations and Distribution of Trace Metals in Water and Streambed Sediments of Orogodo River, Southern Nigeria  

Microsoft Academic Search

The distribution of Cd, Pb, Ni, Cr, Cu, Mn, Fe, and Zn in sediment and surface water, and some physico-chemical characteristics of Orogodo river sediments, were evaluated. The sediment pH ranged from 5.1–7.3; conductivity values ranged from 34.5 to 389.0 ?Scm. Total nitrogen values ranged from 0.06–0.10%, NH3-N values ranged from 0.25–0.44 mgkg, percent total organic carbon ranged from 0.21–1.68%,

Chukwujindu M. A. Iwegbue; Francis O. Arimoro; Godwin E. Nwajei; Osayonmo I. Eguavoen

2012-01-01

296

Methane production in the interstitial waters of sulfate-depleted marine sediments.  

PubMed

Methane in the interstitial waters of anoxic Long Island Sound sediments does not reach appreciable concentrations until about 90 percent of seawater sulfate is removed by sulfate-reducing bacteria. This is in agreement with laboratory studies of anoxic marine sediments sealed in jars, which indicate that methane production does not occur until dissolved sulfate is totally exhausted. Upward diffusion of methane or its production in sulfate-free microenvironments, or both, can explain the observed coexistence of measurable concentrations of methane and sulfate in the upper portions of anoxic sediments. PMID:17835470

Martens, C S; Berner, R A

1974-09-27

297

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...

298

ANALYSIS OF NATIONAL WATER POLLUTION CONTROL POLICIES. 2. AGRICULTURAL SEDIMENT CONTROL  

EPA Science Inventory

Application of a national water network model permits an analysis of the likely effects of agricultural sediment control policies on the quality of the nation's waters. This analysis is believed superior to previous assessments based mainly on erosion estimates without accounting...

299

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

300

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

301

Distribution of cadmium, chromium, copper, lead and zinc in marine sediments in Hong Kong waters  

Microsoft Academic Search

Partitioning of heavy metals (Cd, Cr, Cu, Pb, Zn) in marine sediments collected from various sites in Hong Kong waters were\\u000a determined using sequential extraction method. Sediments from Kellette Bank, located in Victoria Harbour, had higher metal\\u000a concentrations especially Cu and Zn than most other sites. Slightly over 20% of total Cu and Cr existed as readily available\\u000a forms in

S. C. Choi; Onyx W. H. Wai; Thomas W. H. Choi; X. D. Li; C. W. Tsang

2006-01-01

302

Determination of DDT and Metabolites in Surface Water and Sediment Using LLE, SPE, ACE and SE  

Microsoft Academic Search

Surface water and sediment samples collected from Jukskei River in South Africa, were subjected to different extraction techniques,\\u000a liquid–liquid (LLE), solid-phase extraction (SPE), activated carbon extraction (ACE) and soxhlet extraction (SE) for sediment.\\u000a The samples were extracted with dichloromethane, cleaned in a silica gel column and the extracts quantified using a Varian\\u000a 3800 GC-ECD. The percentage recovery test for 2,4?DDT,

Linda L. Sibali; Jonathan O. Okonkwo; Caliphs Zvinowanda

2009-01-01

303

[Vegetation influence on nutrients distribution in pore water of salt marsh sediment].  

PubMed

The variations of nutrients in pore water of salt marsh sediment were surveyed in the middle intertidal zone of Chongming Dongtan during August 2007 to May 2008 to identify plant impact on nutrients distribution. The results show that NH4(+) -N and PO4(3-) -P concentrations are lower in pore water of Spartina alterniflora and Phragmites australis zones than in bare flat, and specially, NH4(+) -N concentrations in summer and autumn decrease by one more orders of magnitude. Compared to winter, nutrients concentrations are obviously higher during the period of plant growth, and plant biomass is clearly correlative to nitrogen and phosphorus. Vegetation growth influences nitrogen content intensively. NH4(-) -N concentrations in Spartina alterniflora and Phragmites australis zones are 44.21 and 74.38 micromol x L(-1) respectively, distinctly lower than that in bare flat and Scirpus mariquete zone (340.14 and 291.87 micromol x L(-1) respectively). Moreover, NO(x)(-) -N concentration is one to two order(s) of magnitude lower than NH4(+) -N, and its highest value exists in Phragmites australis zone (5.94 micromol x L(-1)). The results of molecule diffusive flux of nutrients in the surface sediment-overlying water interface indicate that marsh sediment is the source for SiO3(2-) -Si, NH4(+) -N and PO4(3-) -P, and the rank for NO(x)(-) -N (NO3(-) -N + NO2(-) -N), and NO(x)(-) -N flux from overlying water to sediment [16.23 micromol x (m2 x h)(-1)] is higher than NH4(+) -N flux from sediment to overlying water [15.53 micromol x (m2 x h)(-1)]. Vegetation growth accommodates nutrient structure of the estuarine ecosystem by affecting sediment-water interface mass flux and nutrient ratios in pore water and overlying water. PMID:20063731

Wang, Wei-Wei; Li, Dao-Ji; Gao, Lei

2009-11-01

304

A comparison of solids collected in sediment traps and automated water samplers  

USGS Publications Warehouse

Sediment traps are being used in some pollution monitoring programs in the USA to sample suspended solids for contaminant analyses. This monitoring approach assumes that the characteristics of solids obtained in sediment traps are the same as those collected in whole-water sampling devices. We tested this assumption in the upper Mississippi River, based on the inorganic particle-size distribution (determined with a laser particle- analyzer) and volatile matter content of solids (a surrogate for organic matter). Cylindrical sediment traps (aspect ratio 3) were attached to a rigid mooring device and deployed in a flowing side channel in Navigation Pool 7 of the upper Mississippi River. On each side of the mooring device, a trap was situated adjacent to a port of an autosampler that collected raw water samples hourly to form 2-d composite samples. Paired samples (one trap and one raw water, composite sample) were removed from each end of the mooring device at 2-d intervals during the 30-d study period and compared. The relative particle collection efficiency of paired samplers did not vary temporally. Particle-size distributions of inorganic solids from sediment traps and water samples were not significantly different. The volatile matter content of solids was lesser in sediment traps (mean, 9.5%) than in corresponding water samples (mean, 22.7%). This bias may have been partly due to under-collection of phytoplankton (mainly cyanobacteria), which were abundant in the water column during the study. The positioning of water samplers and sediment traps in the mooring device did not influence the particle-size distribution or total solids of samples. We observed a small difference in the amount of organic matter collected by water samplers situated at opposite ends of the mooring device.

Bartsch, L.A.; Rada, R.G.; Sullivan, J.F.

1996-01-01

305

Radium isotopes as a tracer of sediment-water column exchange in the North Sea  

NASA Astrophysics Data System (ADS)

column exchange plays an important role in coastal biogeochemistry. We utilize short-lived radium isotopes (224Ra and 223Ra) to understand and quantify the dominant processes governing sediment-water column exchange throughout the North Sea. Our comprehensive survey, conducted in September 2011, represents the first of its kind conducted in the North Sea. We find that two main sources regulate surface Ra distributions: minor coastal input from rivers and shallow mudflats and North Sea sediments as the dominant source. Pore waters show 100-fold larger activities than the water column. North Sea sediment characteristics such as porosity and mean grain size, as well as turbulence at the sediment-water interface, are the dominant factors contributing to variability of Ra efflux. Ra inventory and mass balance approaches consistently yield high benthic Ra effluxes in the southern North Sea, driven by strong tidal and wind mixing, which in turn cause high sediment irrigation rates. These results exceed incubation-based Ra flux estimates and the majority of previously reported Ra flux estimates for other regions. Ra-based estimates of benthic alkalinity fluxes compare well to observed values, and the high rates of Ra efflux imply a potentially significant exchange of other products of sedimentary reactions, including carbon and nutrient species. Passive tracer simulations lend strong support to the Ra source attribution and imply seasonal variation in the surface water Ra distribution depending on stratification conditions.

Burt, W. J.; Thomas, H.; Pätsch, J.; Omar, A. M.; Schrum, C.; Daewel, U.; Brenner, H.; Baar, H. J. W.

2014-08-01

306

Path sampling method for modeling overland water flow, sediment transport, and short term terrain evolution in Open Source GIS  

E-print Network

relationship between sediment transport capacity and detach- ment developed for the USDA Water Erosion1479 Path sampling method for modeling overland water flow, sediment transport, and short term-scale/multi-process treatments. It has been used to develop simulation tools for overland shallow water flow and for sed- iment

Thaxton, Christopher S.

307

The influence of geology and land use on arsenic in stream sediments and ground waters in New England, USA  

E-print Network

The influence of geology and land use on arsenic in stream sediments and ground waters in New July 2006 Abstract Population statistics for As concentrations in rocks, sediments and ground water century in the region. The variation of As in bedrock ground water wells has a strong positive correlation

308

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

309

Land subsidence in Yunlin, Taiwan, due to Agricultural and Domestic Water Use  

NASA Astrophysics Data System (ADS)

Subsidence in a layered aquifer is caused by groundwater excess extraction and results in complicated problems in Taiwan. Commonly, responsibility to subsidence for agricultural and domestic water users is difficulty to identify due to the lack of quantitative evidences. An integrated model was proposed to analyze subsidence problem. The flow field utilizes analytical solution for pumping in a layered system from Neuman and Witherspoon (1969) to calculate the head drawdown variation. The subsidence estimation applies Terzaghi (1943) one-dimensional consolidation theory to calculate the deformation in each layer. The proposed model was applied to estimate land subsidence and drawdown variation at the Yuanchang Township of Yunlin County in Taiwan. Groundwater data for dry-season periods were used for calibration and validation. Seasonal effect in groundwater variation was first filtered out. Dry-season pumping effect on land subsidence was analyzed. The results show that multi-layer pumping contributes more in subsidence than single-layer pumping on the response of drawdown and land subsidence in aquifer 2 with a contribution of 97% total change at Yuanchang station. Pumping in aquifer 2 contributes more significant than pumping in aquifer 3 to cause change in drawdown and land subsidence in aquifer 2 with a contribution of 70% total change at Yuanchang station. Larger area of subsidence in Yuanchang Township was attributed pumping at aquifer 2 while pumping at aquifer 3 results in significant subsidence near the well field. The single-layer user contributes most area of subsidence but the multi-layer user generates more serious subsidence.

Hsu, K.; Lin, P.; Lin, Z.

2013-12-01

310

Sediment desiccation as a driver of phosphate availability in the water column of Mediterranean wetlands.  

PubMed

Sediment desiccation is expected to drastically affect nutrient cycling in Mediterranean wetlands as global climate change models predict that many areas will become significantly drier than they currently are. In this study, we selected two Mediterranean wetlands that clearly differ in their water chemical composition (Honda and Hituelo wetlands) in order to determine the impact of sediment desiccation on phosphate (PO?(3-)) adsorption and desorption properties. A decrease in PO?(3-) sorption properties was observed in transects from the littoral zone to dry land in both lakes concomitantly with a reduction in organic matter content, revealing a critical role of organic matter for sequestering P in the lake sediment. Our experiments designed to determine if drying events would lead to an enhanced P release upon re-wetting have shown that, simulating natural conditions of re-flooding (that is without adding sodium azide), PO?(3-) concentrations were notably higher in the overlying water than those initially measured in the lake water. These results highlight the impact of drying sediment and the subsequent re-wetting on increasing P concentrations in lake water and accordingly, affecting to lake trophic state. Finally, we aimed on determining the overall effect of biotic versus abiotic activity on P release patterns observed upon re-wetting. Our results have evidenced that while in Honda, biotic processes upon re-wetting are crucial for increasing P retention in the sediment; P exchange across sediment and water upon dry sediment re-wetting is basically mediated by abiotic processes in Hituelo. PMID:23988744

Gilbert, Juan Diego; Guerrero, Francisco; de Vicente, Inmaculada

2014-01-01

311

Diffusive release of uranium from contaminated sediments into capillary fringe pore water  

SciTech Connect

Despite remediation efforts at the former nuclear weapons facility at the Hanford site (Washington State), leaching of uranium (U) from contaminated sediments to the ground water persists at the Hanford 300 Area. Flooding of contaminated capillary fringe sediments due to seasonal changes in the Columbia River stage has been identified as a reason of continued U supply to ground water. We investigated the release of U from Hanford capillary fringe sediments to pore water. Contaminated Hanford sediments were packed into reservoirs of centrifugal filter devices and saturated with Columbia River water for 3 to 84 days at varying solution-to-solid ratios (1:3, 1:1, 5:1, 10:1, 25:1 mL:g). After specified times, samples were centrifuged to a gravimetric water content of 0.11 ± 0.06 g g-1. Within the first three days, there was an initial rapid release of 6-9% of total U from the sediments into the pore water, independent of the solution-to-solid ratio. After 14 days of reaction, however, the experiments with the narrowest solution-to-solid ratios (1:3 and 1:1 mL:g) showed a decline in dissolved U concentrations. The removal of U from the solution phase was accompanied by removal of Ca and HCO3-. Geochemist workbench simulations, conducted using measured solution concentrations from experiments, indicated that calcite could precipitate in the 1:3 solution-to-solid ratio experiment. After the rapid initial release in the first three days for the 5:1, 10:1, and 25:1 solution-to-solid ratio experiments, there was sustained release of U into the pore water. Up to 22% of total U was released on day 84 for the 25:1 solution-to-solid ratio reaction. This sustained release of U from the sediments had diffusion-limited kinetics.

Rod, Kenton A.; Wellman, Dawn M.; Flury, Markus; Pierce, Eric M.; Harsh, James B.

2012-10-01

312

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.

313

[Indication of Northern Caspian regions by biochemical (enzymatic) indices of water and bottom sediments].  

PubMed

We evaluated ecological status in the region of mixing of river and sea waters in the northern Caspian Sea with high anthropogenic pressure. We studied the regions of Volga River fore-delta, the water areas neighboring ancient hydrological transects, and the sea regions between the transects. The water areas were evaluated by biochemical degradation of organic compounds (proteinase and amylase activities) in water and bottom sediments as well as hydrochemical indices of water (salt composition and contents of dissolved oxygen and biogenic compounds). In conditions of active vegetation of phytoplankton and higher aquatic plants soon after the highest wave of the Volga flood, we studied distribution of hydrolytic enzyme activities involved in the global production/destruction cycle of high molecular weight organic compounds (proteins and polysaccharides). The data obtained with the trypsin-azocasein and alpha-amylase-modified starch tests indicates pollution of water and surface sediments in the lower reaches of Volga and the inflow sea regions. PMID:14735793

Korneeva, G A; Miroshnik, L Iu; Tsytsarin, A G

2003-01-01

314

Water volume and sediment accumulation in Lake Linganore, Frederick County, Maryland, 2009  

USGS Publications Warehouse

To assist in understanding sediment and phosphorus loadings and the management of water resources, a bathymetric survey was conducted at Lake Linganore in Frederick County, Maryland in June 2009 by the U.S. Geological Survey, in cooperation with the City of Frederick and Frederick County, Maryland. Position data and water-depth data were collected using a survey grade echo sounder and a differentially corrected global positioning system. Data were compiled and edited using geographic information system software. A three-dimensional triangulated irregular network model of the lake bottom was created to calculate the volume of stored water in the reservoir. Large-scale topographic maps of the valley prior to inundation in 1972 were provided by the City of Frederick and digitized. The two surfaces were compared and a sediment volume was calculated. Cartographic representations of both water depth and sediment accumulation were produced along with an area/capacity table. An accuracy assessment was completed on the resulting bathymetric model. Vertical accuracy at the 95-percent confidence level for the collected data, the bathymetric surface model, and the bathymetric contour map was calculated to be 0.95 feet, 1.53 feet, and 3.63 feet, respectively. The water storage volume of Lake Linganore was calculated to be 1,860 acre-feet at full pool elevation. Water volume in the reservoir has decreased by 350 acre-feet (about 16 percent) in the 37 years since the dam was constructed. The total calculated volume of sediment deposited in the lake since 1972 is 313 acre-feet. This represents an average rate of sediment accumulation of 8.5 acre-feet per year since Linganore Creek was impounded. A sectional analysis of sediment distribution indicates that the most upstream third of Lake Linganore contains the largest volume of sediment whereas the section closest to the dam contains the largest amount of water. In comparison to other Maryland Piedmont reservoirs, Lake Linganore was found to have one of the lowest sedimentation rates at 0.26 cubic yards per year per acre of drainage area. Sedimentation rates in other comparable Maryland reservoirs were Prettyboy Reservoir (filling at a rate of 2.26 cubic yards per year per acre), Loch Raven Reservoir (filling at a rate of 0.88 cubic yards per year per acre) and Piney Run Reservoir (filling at a negligible rate).

Sekellick, Andrew J.; Banks, S.L.

2010-01-01

315

Can sediment data be used to predict alkalinity and base cation chemistry of surface waters?  

PubMed

We hypothesise that stream sediment elemental composition can predict mean and minimum concentrations of alkalinity, Ca and Mg in the river water throughout a river network. We tested this hypothesis for the River Derwent catchment in North Yorkshire, England, by using 6 years of water chemistry data from the Environment Agency and a digital elevation model to flow path-weight British Geological Survey (BGS) sediment element concentration data. The predictive models for mean concentrations were excellent for Ca and alkalinity, but less good for Mg, and did not require land use data inputs as stream water sediment composition seems to reflect all aspects of the riparian zone soil system. Predictive model forms were linear. Attempts to predict minimum values for Ca and alkalinity also were less satisfactory. This probably is due to variations in hydrological response times to individual precipitation events across the catchment. PMID:21051075

Begum, S; McClean, C J; Cresser, M S; Breward, N

2010-12-15

316

Laboratory upwelled radiance and reflectance spectra of Kerr reservoir sediment waters  

NASA Technical Reports Server (NTRS)

Reflectance, chromaticity, and several other physical and chemical properties were measured for various water mixtures of bottom sediments taken from two sites at Kerr Reservoir, Virginia. Mixture concentrations ranged from 5 to 1000 ppm by weight of total suspended solids (TSS) in filtered deionized tap water. The two sets of radiance and reflectance spectra obtained were similar in shape and magnitude for comparable values of TSS. Upwelled reflectance was observed to be a nonlinear function of TSS with the degree of curvature a function of wavelength. Sediment from the downstream site contained a greater amount of particulate organic carbon than from the upstream site. No strong conclusions can be made regarding the effects of this difference on the radiance and reflectance spectra. Near-infrared wavelengths appear useful for measuring highly turbid water with concentrations up to 1000 ppm or more. Chromaticity characteristics do not appear useful for monitoring sediment loads above 150 ppm.

Witte, W. G.; Whitlock, C. H.; Morris, W. D.; Gurganus, E. A.

1982-01-01

317

Concentration and distribution of antibiotics in water-sediment system of Bosten Lake, Xinjiang.  

PubMed

This study investigated the residues of four sulfonamides, four quinolones, and four tetracyclines in surface water as well as surficial sediment samples, of Bosten Lake, in Xinjiang, China. The results showed the presence of 10 out of the 12 selected antibiotics in both water and sediment. Lomefloxacin was not detected in any of the samples. Among the 12 antibiotics considered, ciprofloxacin, with median concentrations of 39.22 ng L(-1) in surface water and 76.51 ?g kg(-1) in surficial sediment, was the dominant antibiotic in all samples. The sorption coefficient values presented higher sorption capacities of tetracycline and chlortetracycline than the other antibiotics. The cluster analysis revealed elevated levels of pollution in sampling sites 1, 2, and 3, which were situated in a nearby urban area and in the estuary of Kaidu River. This study demonstrates the necessity of regulating the use of antibiotics and improving the management and treatment of their release. PMID:24809500

Lei, Xiaoning; Lu, Jianjiang; Liu, Zilong; Tong, Yanbin; Li, Shanman

2015-02-01

318

Stratigraphic controls on fluid and solute fluxes across the sediment-water interface of an estuary  

USGS Publications Warehouse

Shallow stratigraphic features, such as infilled paleovalleys, modify fresh groundwater discharge to coastal waters and fluxes of saltwater and nutrients across the sediment–water interface. We quantify the spatial distribution of shallow surface water–groundwater exchange and nitrogen fluxes near a paleovalley in Indian River Bay, Delaware, using a hand resistivity probe, conventional seepage meters, and pore-water samples. In the interfluve (region outside the paleovalley) most nitrate-rich fresh groundwater discharges rapidly near the coast with little mixing of saline pore water, and nitrogen transport is largely conservative. In the peat-filled paleovalley, fresh groundwater discharge is negligible, and saltwater exchange is deep (?1 m). Long pore-water residence times and abundant sulfate and organic matter promote sulfate reduction and ammonium production in shallow sediment. Reducing, iron-rich fresh groundwater beneath paleovalley peat discharges diffusely around paleovalley margins offshore. In this zone of diffuse fresh groundwater discharge, saltwater exchange and dispersion are enhanced, ammonium is produced in shallow sediments, and fluxes of ammonium to surface water are large. By modifying patterns of groundwater discharge and the nature of saltwater exchange in shallow sediments, paleovalleys and other stratigraphic features influence the geochemistry of discharging groundwater. Redox reactions near the sediment–water interface affect rates and patterns of geochemical fluxes to coastal surface waters. For example, at this site, more than 99% of the groundwater-borne nitrate flux to the Delaware Inland Bays occurs within the interfluve portion of the coastline, and more than 50% of the ammonium flux occurs at the paleovalley margin.

Sawyer, Audrey H.; Lazareva, Olesya; Kroeger, Kevin D.; Crespo, Kyle; Chan, Clara S.; Stieglitz, Thomas; Michael, Holly A.

2014-01-01

319

Release of elements to natural water from sediments of Lake Roosevelt, Washington, USA  

USGS Publications Warehouse

Reservoir sediments from Lake Roosevelt (WA, USA) that were contaminated with smelter waste discharged into the Columbia River (BC, Canada) were examined using three measures of elemental release reflecting varying degrees of physical mixing and time scales. Aqueous concentrations of Cd, Cu, Pb, and Zn in the interstitial water of reservoir sediments, in the gently stirred overlying waters of incubated sediment cores, and in supernatants of aggressively tumbled slurries of reservoir sediments generally were higher than the concentrations from a reference site. When compared to chronic water-quality criteria, all three measures of release suggest that slag-contaminated sediments near the U.S.-Canadian border are potentially toxic as a result of Cu release and Pb release in two of the three measures. All three measures of Cd release suggest potential toxicity for one site farther down the reservoir, probably contaminated as a result of transport and adsorption of Cd from smelter liquid waste. Releases of Zn and As did not appear to be potentially toxic. Carbonate geochemistry indirectly affects the potential toxicity by increasing water hardness.

Paulson, Anthony J.; Cox, Stephen E.

2007-01-01

320

Diffusive release of uranium from contaminated sediments into capillary fringe pore water  

NASA Astrophysics Data System (ADS)

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 84 days 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 14 days 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 HCO3-. 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.

Rod, Kenton A.; Wellman, Dawn M.; Flury, Markus; Pierce, Eric M.; Harsh, James B.

2012-10-01

321

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

2012-10-01

322

Identification of Water-Quality Trends Using Sediment Cores from Dillon Reservoir, Summit County, Colorado  

USGS Publications Warehouse

Since the construction of Dillon Reservoir, in Summit County, Colorado, in 1963, its drainage area has been the site of rapid urban development and the continued influence of historical mining. In an effort to assess changes in water quality within the drainage area, sediment cores were collected from Dillon Reservoir in 1997. The sediment cores were analyzed for pesticides, polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs), and trace elements. Pesticides, PCBs, and PAHs were used to determine the effects of urban development, and trace elements were used to identify mining contributions. Water-quality and streambed-sediment samples, collected at the mouth of three streams that drain into Dillon Reservoir, were analyzed for trace elements. Of the 14 pesticides and 3 PCBs for which the sediment samples were analyzed, only 2 pesticides were detected. Low amounts of dichloro-diphenyldichloroethylene (DDE) and dichloro-diphenyldichloroethane (DDD), metabolites of dichlorodiphenyltrichloroethane (DDT), were found at core depths of 5 centimeters and below 15 centimeters in a core collected near the dam. The longest core, which was collected near the dam, spanned the entire sedimentation history of the reservoir. Concentrations of total combustion PAH and the ratio of fluoranthene to pyrene in the core sample decreased with core depth and increased over time. This relation is likely due to growth in residential and tourist populations in the region. Comparisons between core samples gathered in each arm of the reservoir showed the highest PAH concentrations were found in the Tenmile Creek arm, the only arm that has an urban area on its shores, the town of Frisco. All PAH concentrations, except the pyrene concentration in one segment in the core near the dam and acenaphthylene concentrations in the tops of three cores taken in the reservoir arms, were below Canadian interim freshwater sediment-quality guidelines. Concentrations of arsenic, cadmium, chromium, copper, lead, and zinc in sediment samples from Dillon Reservoir exceeded the Canadian interim freshwater sediment-quality guidelines. Copper, iron, lithium, nickel, scandium, titanium, and vanadium concentrations in sediment samples decreased over time. Other elements, while no trend was evident, displayed concentration spikes in the down-core profiles, indicating loads entering the reservoir may have been larger than they were in 1997. The highest concentrations of copper, lead, manganese, mercury, and zinc were detected during the late 1970's and early 1980's. Elevated concentrations of trace elements in sediment in Dillon Reservoir likely resulted from historical mining in the drainage area. The downward trend identified for copper, iron, lithium, nickel, scandium, titanium, and vanadium may be due in part to restoration efforts in mining-affected areas and a decrease in active mining in the Dillon Reservoir watershed. Although many trace-element core-sediment concentrations exceeded the Canadian probable effect level for freshwater lakes, under current limnological conditions, the high core-sediment concentrations do not adversely affect water quality in Dillon Reservoir. The trace-element concentrations in the reservoir water column meet the standards established by the Colorado Water Quality Control Commission. Although many trace-element core-sediment concentrations exceeded the Canadian probable effect level for freshwater lakes, under current limnological conditions, the high core-sediment concentrations do not adversely affect water quality in Dillon Reservoir. The trace-element concentrations in the reservoir water column meet the standards established by the Colorado Water Quality Control Commission.

Greve, Adrienne I.; Spahr, Norman E.; Van Metre, Peter C.; Wilson, Jennifer T.

2001-01-01

323

Effects of light, microbial activity, and sediment resuspension on the phosphorus immobilization capability of drinking water treatment residuals in lake sediment.  

PubMed

Drinking water treatment residuals (WTRs), nonhazardous by-products generated in a drinking water treatment plant, can be reused to immobilize phosphorus (P) to control the internal P loading from lake sediments for eutrophication control. Reasonably, before practical application, it is essential to determine the P immobilization capability of WTRs in lake sediments under various conditions. In this work, laboratory scale experiments were conducted to investigate the effects of light, microbial activity, and sediment resuspension on the P immobilization capability of WTRs. The results suggested that absence of light, low microbial activity, and sediment resuspension can increase the internal P loading from lake sediments. WTRs can, however, reduce the internal P loading significantly. Further analysis demonstrated that WTRs can stabilize P, decreasing the P bioavailability in the sediments under varied conditions. WTRs also presented little undesirable effects on the dissolved oxygen levels and pH of overlying water. Therefore, light, microbial activity, and sediment resuspension have little effect on the P immobilization capability of WTRs in lake sediments. PMID:23749370

Wang, Changhui; Pei, Yuansheng

2013-12-01

324

Assessment of arsenic concentrations in domestic well water, by town, in Maine 2005-09  

USGS Publications Warehouse

Prior studies have established that approximately 10 percent of domestic wells in Maine have arsenic levels greater than the U.S. Environmental Protection Agency maximum contaminant limit (10 micrograms per liter (ug/L)). Of even greater concern are multiple discoveries of wells with very high arsenic levels (> 500 ug/L) in several areas of the State. A study was initiated to assist the Maine Center for Disease Control and Prevention (ME-CDC) in developing a better understanding of the statewide spatial occurrence of wells with elevated arsenic levels at the individual town level, identify areas of the State that should be targeted for increased efforts to promote well-water testing, and generate data for potential use in predicting areas of the State likely to have very high levels of arsenic. The State's Health and Environmental and Testing Laboratory (HETL) annually analyzes samples from thousands of domestic wells for arsenic. Results of arsenic analyses of domestic well water submitted to the HETL from 2005 to 2009 were screened and organized, by town, in order to summarize the results for all towns with samples submitted to the HETL. In order to preserve the privacy of well owners, the screening and organization of samples was conducted in the offices of the ME-CDC, following applicable Maine and United States laws, rules, and privacy policies. After screening, the database contained samples from 531 towns in Maine and from 11,111 individual wells. Of those towns, 385 had samples from 5 or more individual wells, 174 towns had samples from 20 or more individual wells, and 49 towns had samples from 60 or more wells. These samples, because they were submitted by homeowners and were not part of a random sample, may not be representative of all wells in a given area. The minimum, maximum, and median arsenic values for the towns with five or more samples were calculated, and the maximum and median values were mapped for the State. The percentages of samples exceeding 10, 50, 100, and 500 ug/L were calculated for the 174 towns with 20 or more sampled wells, and statewide maps were prepared for each of these categories. More than 25 percent of the sampled wells in 44 towns exceeded 10 ug/L. Many fewer towns had wells with samples that exceeded the 50, 100, or 500 ug/L categories. For 19 towns, more than 10 percent of the sampled wells had arsenic concentrations that exceeded 50 ug/L, and in 45 towns, 1 percent or more exceeded 100 ug/L. Of these, Surry in Hancock County had 120 wells tested, and 23 percent of those wells had arsenic concentrations that exceeded 100 ug/L, which is a much higher rate than for other towns. In only four towns (Danforth in Washington County, Surry and Blue Hill in Hancock County, and Woolwich in Sagadahoc County), 1 percent or more of the sampled wells had arsenic concentrations greater than 500 ug/L during 2005-09. The distribution of high arsenic concentrations in wells follows some geographic patterns, which are generally geologically controlled. There are clusters or belts of towns with high arsenic concentrations (> 50 ug/L), such as in southern coastal areas, the Kennebec County area, and towns along the central coastal part of Maine. In contrast, there are areas of the State with low arsenic concentrations, such as the northernmost towns, as well as towns in the western and west-central areas. There appear to be three distinct large-scale areas of high concentrations of arsenic in groundwater-one in southern coastal areas, one in central Kennebec County, and one in the town of Ellsworth (Hancock County) and the surrounding areas. In addition, several smaller clusters of isolated high concentrations of arsenic in groundwater exist. Earlier testing has identified other clusters of very high arsenic concentrations in groundwater in the towns of Northport, Buxton/Hollis, and Waldoboro, but those samples were collected before 2005 and did not factor in this analysis.

Nielsen, M.G.; Lombard, P.J.; Schalk, L.F.

2010-01-01

325

SEDIMENT PHOSPHORUS RELEASE REDUCES THE EFFECT OF THE CHAIN LAKE WATER DIVERSION  

Microsoft Academic Search

In 1968, a 2 km long water diversion was built to flush Chain Lake, British Columbia with nutrient-poor subai-pine water. Unfortunately in some years, blue-green algal blooms (chl a> 100 ?g\\/L) and fish kills still occur. The incomplete success of the diversion is related to the asynchrony of water flow and phosphorus release from the sediments. Internal loading represents about

Tom Murphy

1987-01-01

326

Phthalate esters in water and sediments of the Kaveri River, India: environmental levels and ecotoxicological evaluations.  

PubMed

Phthalate esters are well known for their environmental contamination and toxicological effects as "endocrine disruptors." In this study, environmental levels of phthalate esters and ecotoxicological risk assessments were performed in one of the major rivers in India, the Kaveri. Water and sediment samples were collected during 2010-2012 representing the major stretch of the river and extracted by solid-phase and ultrasonic methods, respectively, and analyzed for six major phthalates by using a gas chromatograph-mass spectrometer. The analytical recovery for phthalates in water and sediment ranged from 79 to 121 %. Results indicated that diethyl phthalate (DEP) and dimethyl phthalate were found in every sample, whereas butylbenzyl phthalate and diethylhexyl phthalate (DEHP) were detected in 92 % of the water samples. Likewise, in sediment samples, DEP was found most often (94 %). The total phthalates in water samples ranged from 313 to 1,640 ng/l, whereas in sediments it was 2 to 1,438 ng/g dw (dry weight) with DEHP having the highest concentration. Human health risk assessment based on drinking water consumption showed no potential risk for phthalates and also DEHP levels were safe with respect to USEPA guideline (6,000 ng/l). Further, DEHP and di-n-octyl phthalate levels in water were expected to pose little threat to sensitive organisms in the riverine ecosystem as per ECOSAR chronic values. In case of sediment, the DEHP concentration was well above the USEPA sediment guideline value. To our knowledge, this is the first study to describe the levels and ecotoxicological risks of phthalates in Kaveri River, India. PMID:25056812

Selvaraj, Krishna Kumar; Sundaramoorthy, Gomathy; Ravichandran, Praveen Kumar; Girijan, Girish Kumar; Sampath, Srimurali; Ramaswamy, Babu Rajendran

2015-02-01

327

Metal speciation and attenuation in stream waters and sediments contaminated by landfill leachate  

NASA Astrophysics Data System (ADS)

The degree of metal contamination (Zn, Pb, Cu, Ni, Cd) has been investigated in the vicinity of an old unmonitored municipal landfill in Prague, Czech Republic, where the leachate is directly drained into a surface stream. The water chemistry was coupled with investigation of the stream sediment ( aqua regia extract, sequential extraction, voltammetry of microparticles) and newly formed products (SEM/EDS, XRD). The MINTEQA2 speciation-solubility calculation showed that the metals (Zn, Pb, Cu, Ni) are mainly present as carbonate complexes in leachate-polluted surface waters. These waters were oversaturated with respect to Fe(III) oxyhydroxides, calcite (CaCO3) and other carbonate phases. Three metal attenuation mechanisms were identified in leachate-polluted surface waters: (i) spontaneous precipitation of metal-bearing calcite exhibiting significant concentrations of trace elements (Fe, Mn, Mg, Sr, Ba, Pb, Zn, Ni); (ii) binding to Fe(III) oxyhydroxides (mainly goethite, FeOOH) (Pb, Zn, Cu, Ni); and (iii) preferential bonding to sediment organic matter (Cu). These processes act as the key scavenging mechanisms and significantly decrease the metal concentrations in leachate-polluted water within 200 m from the direct leachate outflow into the stream. Under the near-neutral conditions governing the sediment/water interface in the landfill environment, metals are strongly bound in the stream sediment and remain relatively immobile.

Ettler, Vojt?ch; Matura, Marek; Mihaljevi?, Martin; Bezdi?ka, Petr

2006-02-01

328

Study of photocatalytic degradation of tributyltin, dibutylin and monobutyltin in water and marine sediments.  

PubMed

This study reports on the first assessment of the treatment of sediments contaminated by organotin compounds using heterogeneous photocatalysis. Photocatalysis of organotins in water was carried out under realistic concentration conditions (?gL(-1)). Degradation compounds were analyzed by GC-ICP-MS; a quasi-complete degradation of tributyltin (TBT) in water (99.8%) was achieved after 30min of photocatalytic treatment. The degradation by photolysis was about (10%) in the same conditions. For the first time decontamination of highly polluted marine sediments (certified reference material and harbor sediments) by photocatalysis proves that the use of UV and the production of hydroxyl radicals are an efficient way to treat organotins adsorbed onto marine sediment despite the complexity of the matrix. In sediment, TBT degradation yield ranged from 32% to 37% after only 2h of irradiation (TiO2-UV) and the by-products: dibutyltin (DBT) and monobutyltin (MBT) were degraded very rapidly in comparison with TBT. It was shown that during photocatalysis of organotins in sediments, the hydroxyl radical attack and photolysis are the two ways for the degradation of adsorbed TBT. PMID:24613444

Brosillon, Stephan; Bancon-Montigny, Chrystelle; Mendret, Julie

2014-08-01

329

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

330

Optimization of analytical methods to improve detection of erythromycin from water and sediment.  

PubMed

Analytical methods to improve the detection of erythromycin in water and sediment were developed to optimize for erythromycin's recovery of extractable and bound residues from the aquatic environment. The objective of this study was to determine optimal recovery of erythromycin from water and sediment to improve its detection in environmental samples through solid-phase extraction (SPE) and sediment-extraction methods. SPE methods examined included previously reported methods for macrolide and sulfonamide antibiotics with erythromycin recoveries ranging from 75.5 % to 94.7 %. Extraction of erythromycin was performed from sand employing various solvents and buffers to determine the best method for extraction from two sandy loam pond sediments. Various extraction times were also examined, and all extraction procedures were performed in duplicate. The greatest recovery of (14)C-erythromycin in the Iowa sediment was 84 % using 0.3 M ammonium acetate at pH 4.2: acetonitrile (15:85, v/v) solution. The Oklahoma sediment yielded the greatest recovery of (14)C-erythromycin at 86.7 % with 0.3 M ammonium acetate at pH 7: acetonitrile (30:70, v/v) with a 60-minute shake time. The present results demonstrate improved extraction methods for enhancing the accuracy of erythromycin detection from environmental samples. PMID:21877980

Jessick, Ashley M; Moorman, Thomas B; Coats, Joel R

2011-01-01

331

Organic contaminant transport in ground water, surface water, and surface water sediments: Year 1 progress report  

Microsoft Academic Search

Questions concerning the transport and fate of contaminants in the environment have typically been limited to single compounds. Hazardous-waste disposal facilities, chemical plants, oil refineries, etc., however, typically produce complex waste streams which may contact groundwater or surface waters. The study gives results on movement through ground and surface water of a complex mixture of organic compounds emanating from a

M. J. Crossey; H. L. Bergman

1984-01-01

332

Geochemical cycling and speciation of copper in waters and sediments of Macquarie Harbour, Western Tasmania  

NASA Astrophysics Data System (ADS)

The factors determining the concentration and speciation of copper in the waters and sediments of Macquarie Harbour, Tasmania were investigated. This harbour is the most extensively copper-contaminated estuarine water body in Australia owing to current and historical inputs of metal-rich waters and sediments from the nearby Mount Lyell copper mine. The dissolved copper concentrations in the harbour water column were highly variable (4-560 ?g l -1) and displayed a north to south gradient, decreasing with distance from the King River, which carries the inputs from the mine. The most significant process affecting dissolved copper concentrations was the neutralisation of acidic river waters with seawater and the resulting coprecipitation with iron oxyhydroxide flocs. Approximately 60% of the riverine dissolved copper input was removed from solution by this process. Particulate copper concentrations in surficial benthic sediments were high in most regions of the harbour (typically 0.5-1 mg g -1). In the north, sediments were dominated by fine, mine-derived material and showed uniform particulate copper concentrations with depth. Sediment acid-volatile sulphide concentrations were highest (11-142 ?mol g -1) in the southern harbour and were barely detectable in the northern harbour region (<0.46 ?mol g -1). A similar north-south gradient of sediment organic carbon concentrations was observed. Very high porewater concentrations of copper (up to 520 ?g l -1) and iron (200 mg l -1) were found at sites in the northern harbour. The high porewater copper concentrations are believed to result from the oxidation of porewater Fe(II), formation of amorphous iron oxyhydroxide and the associated pH-related dissolution of particulate copper. Calculations indicated a positive flux of dissolved copper from the sediments at sites in the northern harbour. However, in the southern harbour, the high acid volatile sulphide concentrations of the sediments meant that they acted as a sink for dissolved copper, resulting in low porewater copper concentrations (<1-10 ?g l -1) and a significant copper flux from the overlying water to the sediment. The study illustrates the roles of iron redox chemistry, associated pH gradients, and acid volatile sulphide in controlling copper mobility in contaminated estuarine environments.

Teasdale, P. R.; Apte, S. C.; Ford, P. W.; Batley, G. E.; Koehnken, L.

2003-06-01

333

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

334

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

335

Water and sediment transport modeling of a large temporary river basin in Greece.  

PubMed

The objective of this research was to study the spatial distribution of runoff and sediment transport in a large Mediterranean watershed (Evrotas River Basin) consisting of temporary flow tributaries and high mountain areas and springs by focusing on the collection and use of a variety of data to constrain the model parameters and characterize hydrologic and geophysical processes at various scales. Both monthly and daily discharge data (2004-2011) and monthly sediment concentration data (2010-2011) from an extended monitoring network of 8 sites were used to calibrate and validate the Soil and Water Assessment Tool (SWAT) model. In addition flow desiccation maps showing wet and dry aquatic states obtained during a dry year were used to calibrate the simulation of low flows. Annual measurements of sediment accumulation in two reaches were used to further calibrate the sediment simulation. Model simulation of hydrology and sediment transport was in good agreement with field observations as indicated by a variety of statistical measures used to evaluate the goodness of fit. A water balance was constructed using a 12year long (2000-2011) simulation. The average precipitation of the basin for this period was estimated to be 903mmyr(-1). The actual evapotranspiration was 46.9% (424mmyr(-1)), and the total water yield was 13.4% (121mmyr(-1)). The remaining 33.4% (302mmyr(-1)) was the amount of water that was lost through the deep groundwater of Taygetos and Parnonas Mountains to areas outside the watershed and for drinking water demands (6.3%). The results suggest that the catchment has on average significant water surplus to cover drinking water and irrigation demands. However, the situation is different during the dry years, where the majority of the reaches (85% of the river network are perennial and temporary) completely dry up as a result of the limited rainfall and the substantial water abstraction for irrigation purposes. There is a large variability in the sediment yield within the catchment with the highest annual sediment yield (3.5tha(-1)yr(-1)) to be generated from the western part of the watershed. The developed methodology facilitated the simulation of hydrology and sediment transport of the catchment providing consistent results and suggesting its usefulness as a tool for temporary rivers management. PMID:25497675

Gamvroudis, C; Nikolaidis, N P; Tzoraki, O; Papadoulakis, V; Karalemas, N

2015-03-01

336

Perfluorinated Compounds in River Water, River Sediment, Market Fish, and Wildlife Samples from Japan  

Microsoft Academic Search

Perfluorinated organic compounds (PFCs) such as PFOS, PFOA, PFBS, PFH×S, PFOSA and PFDoA were determined in river water, river\\u000a sediment, liver of market fish and liver of wildlife samples from Japan. Concentrations of PFOA and PFOS in water samples\\u000a were 7.9–110 and <5.2–10 ng\\/L. Only PFOA were detected in sediment from Kyoto river at 1.3–3.9 ng\\/g dry wt. Among fish, only\\u000a jack

Kurunthachalam Senthilkumar; Etsumasa Ohi; Kenneth Sajwan; Takumi Takasuga; Kurunthachalam Kannan

2007-01-01

337

Managing dredged sediment placement in open-water disposal sites, Upper Chesapeake Bay  

USGS Publications Warehouse

The maintenance dredging of fine-grained sediment which accumulated in shipping channels in the Upper Chesapeake was discussed. The capacity of open-water sites was maximized in an environmentally acceptable manner to provide adequate time for the development of beneficial use or confined placement sites. The additional water column turbidity generated by dragging operations and bottom sediment movement during placement raised environmental concerns which weighted against the need to maximize capacity. The inter-agency team overseeing site management provided a mechanism to implement operational changes which maximized site capacity and insured operational use through the projected life span of the site.

Panageotou, W.

2002-01-01

338

Sediment Mobilization From Reservoirs Can Cause Short Term Oxygen Depletion In Downstream Receiving Waters  

NASA Astrophysics Data System (ADS)

Reservoir management can cause incidences of short-term sediment mobilization, e.g. during dam removal or drawdown for maintenance or habitat purposes. Much of the associated planning focuses on predicting, quantifying, and mitigating the physical impacts of sediment mobilization, transport, and deposition. Sediment pulses can cause multiple regulatory and management concerns, such as turbidity or suspended sediment concentrations that may exceed State standards, geomorphic change and effects on property or infrastructure, or wildlife impacts such as stress to fish via gill abrasion or burial of critical habitat. Water-quality issues associated with sediment mobilization, including nutrient and contaminant transport, are often given less attention, presumably because their effects are less immediate or because of resource constraints. Recent experience with large pulses of sediment from several western reservoirs involving dam removals and temporary drawdowns indicates that oxygen demand, leading to depletion of downstream dissolved oxygen (DO), can also be a significant short-term concern. During the October 2011 Condit Dam removal on the White Salmon River in Washington, DO in receiving waters about 4.5 km downstream of the dam dropped to less than 1 mg/L within 2 hours of the demolition; in response, salmonids were observed to be in distress, apparently gulping for air at the water surface. DO remained low for at least 24 hours in this reach, and dead fish were observed. In December 2012, during a drawdown designed to aid juvenile-salmonid migration through Fall Creek Reservoir in Oregon, DO dropped precipitously about 1.5 km downstream as turbidity peaked, and a muted DO decrease was also observed approximately 14 miles further downstream despite a large dilution from unaffected sources. Laboratory experiments and modeling using sediments from reservoirs proposed for removal on the Klamath River, California, demonstrated the likelihood for downstream DO depletion stemming from a combination of chemical (< 2 hr) and biological (days-weeks) oxidation processes, depending on rates of sediment mobilization. Such depletion could contribute to fish stress or mortality for tens of kilometers downstream of the dams and for the duration of the sediment mobilization. Although modeling DO demand and measuring stream DO response during periods of elevated sediment concentration remains an area requiring further research, planning for large sediment mobilizing events could better anticipate and mitigate short-term, acute stresses on fish and aquatic life by recognizing the potential for transient, but significant, DO-related impacts.

Anderson, C.; Schenk, L.; Bragg, H.; Singer, M.; Hume, N.

2013-12-01

339

In Situ Chemical Transformations of Silver Nanoparticles along the Water-Sediment Continuum.  

PubMed

In order to accurately assess the potential environmental risk posed by silver nanoparticles (Ag-NPs), their transformation and fate must be investigated in natural systems. This has proven to be very challenging due to the difficulties encountered in retrieving/analyzing NPs dispersed in complex and heterogeneous environmental matrices at relevant (i.e., low) concentrations. In this study, we overcame this challenge by immobilizing functionalized Ag-NPs onto plasma polymerized solid substrates to form "nano in situ deployment devices" (nIDDs). This method allowed us to retrieve and analyze the Ag-NPs after 48 h of direct exposure in freshwater-sediment and saltwater-sediment environments. The type and extent of Ag-NPs transformation was expected to vary along the water-sediment continuum as sediments typically contain steep gradients in solute concentrations and redox potential. To trace the distribution of redox sensitive elements (e.g., Fe, Mn), Diffusive Equilibration in Thin-films (DET) devices were inserted into the sediments alongside the nIDDs. Chemical transformation of the immobilized Ag-NPs across the water-sediment continuum was investigated after retrieval by synchrotron radiation X-ray Absorption Spectroscopy. Linear combination fitting of Ag K-edge X-ray absorption spectra indicated that the chemical transformations of Ag-NPs in both freshwater and saltwater sediments were strongly affected by the redox conditions over the investigated range. Silver bound to reduced sulfur was the principal product of Ag-NP transformations but different extents of transformation were observed for Ag-NPs exposed to different depths in the sediment. These field results add important insights about the transformation of Ag-NPs in heterogeneous environments. PMID:25405257

Khaksar, Maryam; Jolley, Dianne F; Sekine, Ryo; Vasilev, Krasimir; Johannessen, Bernt; Donner, Erica; Lombi, Enzo

2015-01-01

340

Solar heating, cooling, and domestic hot water system installed at Kaw Valley State Bank and Trust Company, Topeka, Kansas  

NASA Technical Reports Server (NTRS)

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.

1980-01-01

341

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

342

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

2012-11-01

343

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.

2013-06-01

344

Ra isotopes as a tracer of sediment-water column exchange in the North Sea  

NASA Astrophysics Data System (ADS)

Quantifying the benthic flux of short-lived radium isotopes (224Ra and 223Ra) provides information regarding the extent, and the dominant processes governing sediment-water column exchange in the North Sea. For this purpose we employed three independent measurement techniques including sediment incubation chambers, water column inventories, and a surface mass-balance. Incubation results from 11 stations indicate significant spatial variability in Radium efflux throughout the North Sea, as well as a strong dependence on the stirring rate of the overlying water column. Both inventory and mass-balance methods yield consistently higher benthic fluxes for the Southern North Sea than incubation-based estimates due to the inability of the laboratory incubations to recreate the in-situ mixing conditions present in the well-mixed Southern North Sea. Furthermore, fluxes in the Southern North Sea are higher than those previously reported in other regions, likely due to high rates of sediment irrigation induced by strong tidal and wind mixing near the interface of permeable sandy sediments. The seasonality of distributions and the magnitudes of both benthic and coastal Ra fluxes are further examined by applying Ra as a passive tracer in the 3-dimensional hydrodynamics of the ECOSMO model. Finally, flux estimates combined with direct measurements of porewater Ra activities yield volume fluxes [L m-2 d-1], which when further applied to porewater concentrations of carbon or nutrient species, can provide important information regarding the role of sediments in North Sea biogeochemistry.

Burt, William; Thomas, Helmuth; Pätsch, Johannnes; Omar, Abdirahman; Schrum, Corinna; Daewel, Ute

2014-05-01

345

Distribution of metals in water and bed sediment in a mineral-rich watershed, Montana, USA  

USGS Publications Warehouse

We sampled the Blackfoot River (Montana) and its major tributaries from the headwaters of the basin to near its confluence with the Clark Fork River over the course of 5 days in August 1998. We measured streamflow, collected fine-grained (<63 ??m) streambed sediment, and sampled the dissolved (operationally defined as <0.2 ??m) phase of the surface water using clean techniques. Water and sediment collected from near the historic Heddleston mining district contained the highest concentrations of most trace elements in the basin. Many solute trace metals were at their highest several kilometers downstream from the mining district, where the river flows through an unremediated marsh system that has collected mine wastes in the past. Downstream of the headwaters area, water and bed sediment metal concentrations declined sharply. Comparison of sediment samples with those collected by other workers in August 1989 and August 1995 do not show evidence of basin-scale long term changes, despite the onset of remediation efforts in 1993. The area of the proposed McDonald gold deposit near the confluence of the Landers Fork with the Blackfoot River was not contributing anomalous concentrations of naturally-occurring dissolved and bed-sediment metals into the basin. ?? IMWA Springer-Verlag 2002.

Nagorski, S.A.; Moore, J.N.; Smith, D.B.

2002-01-01

346

Occurrence of arsenic in sediment pore waters in the central Kanto Plain, Japan  

NASA Astrophysics Data System (ADS)

The Kanto Plain is known as the largest plain in Japan, where marine sediments are widely developed because of cyclic iteration of global sea-level changes even 50 km or more inland from the present shoreline. In this area, dependence on groundwater for water requirements is relatively high; in particular, around 40 % of the municipal water supply is dependent on groundwater. Arsenic levels greater than that permitted by the environmental standards of Japan have been detected in groundwater in this area. Therefore, to evaluate occurrences of arsenic and other related elements in pore waters contained in natural sediment layers, we measured the levels of various inorganic chemical substances such as arsenic (As), iron (Fe), and sulfur (S) and major dissolved ions such as sulfate (SO42-), calcium (Ca2+), and sodium (Na+). Pore waters were collected from sediment samples that were obtained by a drilling from the river bottom down to 44 m depth; pore water samples were obtained immediately after extraction of sediments. The sedimentary facies in the vertical profile are continental, transitional, and marine, including two aquifers. The upper aquifer (15-20 m) contains fine to medium sand, whereas the lower aquifer (37-44 m) contains medium to coarse and gravelly sand. Arsenic and other inorganic elements were measured by an inductively coupled plasma mass spectrometer (ICP/MS) and an inductively coupled plasma atomic emission spectrometer (ICP/AES), and major dissolved ions were measured by an ion chromatograph analyzer. The total content of chemical elements was measured by X-ray fluorescence analysis using solid sediment samples. We obtained the following results. The arsenic concentrations in pore waters in marine silt and clay sediments (approximately 0.04 mg/L) were about five times higher than that in continental sediments (approximately 0.008 mg/L). The highest concentration of arsenic (0.074 mg/L) was detected at a depth of 13 m, which is immediately above the upper aquifer. Visual observations confirmed that this level is under oxidizing conditions. Thus, it regards that arsenic was adsorbed to iron hydroxide in the sediments. On the other hand, in the top part of the section, from the river bottom to a depth of approximately 3 m, arsenic concentrations in the pore waters were clearly high and decreased gradually and continuously with depth. This is considered to be the result of anthropogenic impact on the river.

Hachinohe, Shoichi; Hamamoto, Hideki; Ishiyama, Takashi; Hossain, Sushmita; Oguchi, Chiaki T.

2014-05-01

347

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

Microsoft Academic Search

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

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

2010-01-01

348

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

349

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

350

[Heavy metal content in sediment samples taken from drinking-water reservoir (author's transl)].  

PubMed

Sediment samples were taken from the small preliminary catchment basin of the Wahnbachtal reservoir at Siegburg, extracted under mild conditions with nitric acid and hydrogen peroxide and analysed for their content of heavy metals. The sediment sample of the most recent date showed the highest concentrations of metal, that of older date revealed lower values, but by far the lowest metal content was found in the clay of the former valley. The high metal contents in the sediment are not only to be attributed to human influence but are primarily caused by the lead and zinc ores in the catchment area. The hygienic significance of these results is to be seen in the remobilization processes which could lead to an undesirable increase of metal concentrations in the raw water fed to the drinking water treatment plant. PMID:998050

Mihm, U; Botzenhart, K; Noeske, K

1976-07-01

351

Environmental Research in China ORGANOCHLORINE PESTICIDES IN THE SURFACE WATER AND SEDIMENTS OF THE PEARL RIVER ESTUARY, SOUTH CHINA  

Microsoft Academic Search

Samples of surface water, suspended particulate matter (SPM), and surface sediment, collected from the Pear River Estuary, Guangdong Province, China in July of 2002 and April of 2003, were analyzed for hexachlorocyclohexanes (HCHs) and dichlorodiphenyltrichloroethanes (DDTs) using gas chromatography with electron capture detection. The levels of total HCHs in water varied from 213 to 3,116 pg\\/L, although in sediments they

MEI YU; XIAOJUN LUO; SHEJUN CHEN; BIXIAN MAI; EDDY Y. Z ENG

352

Collection of intact sediment cores with overlying water to study nitrogen- and oxygen-dynamics in regions with seasonal hypoxia  

Microsoft Academic Search

Settled particles of fresh, labile organic matter may be a significant source of oxygen demand and nutrient regeneration in seasonally-hypoxic regions caused by nutrient inputs into stratified coastal zones. Studying the dynamics of this material requires sediment sampling methods that include flocculent organic materials and overlying water (OLW) at or above the sediment–water interface (SWI). A new coring device (“HYPOX”

Wayne S. Gardner; Mark J. McCarthy; Stephen A. Carini; Afonso C. Souza; Hou Lijun; Karen S. McNeal; Mary Keith Puckett; Jack Pennington

2009-01-01

353

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

Code of Federal Regulations, 2010 CFR

...structure and the reservoir surface at present and under...sediment or slurry level, water level and other information...14) The locations of surface and underground coal mine workings including the depth and extent of such workings...the maximum volume of water, sediment, or...

2010-07-01

354

Determination of metronidazole residues in water, sediment and fish tissue samples.  

PubMed

Metronidazole (MNZ) is an antibacterial and antiprotozoal drug used in veterinary and human medicine. Its continual entry into the environment and its biological properties may have significant, long-term effects on the stability of ecosystems because MNZ and its metabolites possess mutagenic, carcinogenic and toxic properties. For this reason, the application of MNZ in food-producing species is prohibited in the EU, the USA and other countries. To ensure human food safety and to protect the environment, robust and reliable screening and confirmatory tests capable of the low-level detection of MNZ residues are required. The development of methods for MNZ determination in biological and environmental samples is thus an important analytical task in environmental and food science. This work focuses on the evaluation of a method for determining MNZ in water, sediment and fish tissue samples using liquid chromatography - ion trap mass spectrometry (LC-MS/MS). MNZ was extracted from waters on Strata XC cartridges using solid phase extraction (SPE), and from sediments and fish tissues by solid-liquid extraction (sediment: 15mL 0.1M HCl (pH=0.6), 15min; fish tissue: 15mL 1% CH3COOH in ACN, 1min; drying: 5g MgSO4(anhyd.; 30s) with SPE purification of the extracts (from sediment: Strata XC cartridge; from fish tissue: Supelco NH2 cartridge). The optimal procedure that we developed was validated in order to confirm its reliability and sensitivity. Matrix effects (ME) were established. Absolute recoveries ranged from 89.3% to 97.2%, and the method detection limits were 3.4ngL(-1) (water samples), 0.4ngg(-1) (sediment samples) and 0.3ngg(-1) (tissue samples). These methods were used to determine MNZ in surface waters, sediments and fish tissues from the Polish River Go?cicina; MNZ was found in all these matrices. The highest concentrations in water, sediment and tissue were 136.2ngL(-1), 12.0ngg(-1) and 1.5ngg(-1) respectively. The results confirmed that these methods are suitable for the simultaneous analysis of waters, sediments and fish tissues for the presence of MNZ. PMID:24412503

Wagil, Marta; Maszkowska, Joanna; Bia?k-Bieli?ska, Anna; Caban, Magda; Stepnowski, Piotr; Kumirska, Jolanta

2015-01-01

355

Pleistocene meteoric pore water in dated marine sediment cores off Callao, Peru  

NASA Astrophysics Data System (ADS)

During cruise SO 147 of the German research vessel SONNE, a large decrease in salinity with depth was found in the pore water at a site about 10 sea miles off Callao, Lima, Peru. The origin of this freshening was investigated in a multidisciplinary approach using geochemical, geochronological and isotope hydrological methods. The methodology applied is a possible strategy to deal with anomalous pore water freshenings and if necessary to put them into the general framework of submarine groundwater discharge. Concentrations of the major and conservative elements (e.g., Na, K, Cl, B, Br) decrease at the same ratios. Deuterium ( ?D) and oxygen-18 ( ?18O) data reveal the meteoric origin of the fresh water end member, indicating a mixture of 30% seawater and 70% fresh water at a depth in sediment of about 10 m. 210Pb and 137Cs sedimentation rates determined by gamma spectrometry range between 2 and 4.5 mm/y for the last century whereas values derived from AMS 14C for the last millennia give mean rates smaller than 1 mm/y. This indicates strongly varying sedimentation conditions. Nevertheless, from the geochronological data it can be concluded that the origin of the fresh water end member is situated in sediments of Pleistocene age. Literature data of the isotope signature of modern water in the nearby Lima aquifer are clearly different from the calculated values for the fresh water end member in the pore waters. On the basis of the isotopic altitude effect described in the literature, the isotopic signature of the fresh pore water end member can be explained as rain water directly infiltrated into the Lima aquifer. In contrast, this infiltration is negligible there under present-day arid climatic conditions. Theoretical considerations on pore water advective and diffusive transport give further indications that the fresh pore water end member is entrapped paleowater of Pleistocene origin. The observed pore water freshening and the geochemical and geochronological data can be conclusively explained by diffusive mixing of seawater with meteoric water, which infiltrated during the last sea level low stand and stayed entrapped during transgression and sedimentation.

Kriete, Cornelia; Suckow, Axel; Harazim, Bodo

2004-03-01

356

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 O 2(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 O 2(aq) into Montserrat sediments was observed (<1 cmbsf), and inferred to partially reflect oxidation of fine grained Fe(II) minerals, whereas penetration of O 2(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 MnO x 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

357

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...

358

[Impact of wind-water alternate erosion on the characteristics of sediment particles].  

PubMed

Wind and water are the two dominant erosion agents that caused soil and water losses in the wind-water alternate erosion region on the Loess Plateau. It is meaningful to study the impact of wind-water alternate erosion on the characteristics of soil particles for understanding the response of soil quality and environment to erosion. Through wind tunnel combined rainfall simulation, this paper studied the characteristics of the erosive sediment particles under the effect of wind-water alternate erosion. The results showed that the particles of 0-1 cm soil were coarsened by wind erosion at the wind speeds of 11 and 14 m x s(-1) compared with no wind erosion. Soil fine particles (< 0.01 mm) decreased by 9.8%-10.8%, and coarse particles (> 0.05 mm) increased by 16.8%-20.8%. The physical property of surface soil was changed by the wind erosion, which, in turn, caused an increase in finer particles content in the sediment. Compared with no wind erosion, fine particles (< 0.01 mm) in sediment under the water-wind alternate erosion increased by 2.7%-18.9% , and coarse particles (> 0.05 mm) decreased by 3.7%-9.3%. However, the changing trend of erosive sediment particles after the wind erosion at wind speeds of 11 and 14 m x s(-1) was different along with the rainfall intensity and duration. The erosive sediment particles at the rainfall intensities of 60, 80, 100 mm x h(-1) changed to greater extents than at the 150 mm x h(-1) rainfall intensity with longer than 15 min runoff flowing. PMID:24830236

Tuo, Deng-Feng; Xu, Ming-Xiang; Ma, Xin-Xin; Zheng, Shi-Qing

2014-02-01

359

Preservation of forcing signals in shallow water carbonate sediments  

NASA Astrophysics Data System (ADS)

No consensus has been reached on whether the metre-scale cycles that commonly occur in peritidal carbonates are predominately a product of external relative sea-level variations (allocycles) or an intrinsic property of carbonate production generated via the interaction of non-linear processes (autocycles). For any forcing signal such as eustatic sea-level change, to be detectable in stratigraphy its effects must be preserved. Here, a deterministic, three-dimensional geological process model is used to explore how such cycles are preserved in the geological record in the presence of autocyclic processes. Each simulation produced cycle thickness distributions that are statistically indistinguishable from a theoretical Poisson process, regardless of whether auto- or allo-cycles dominated. Spectral analysis of depositional time series constructed from idealised geological sections showed that all detectable signals occurred within the Milankovitch forcing frequency bands, even when no Milankovitch forcing was present. Thus, it is deduced that from any geological section alone, external forcing signals are detectable but are not distinguishable from autocyclically produced signals. Interestingly, there is no correlation between the percentage of sediment preserved and the accuracy with which signals are detectable in the preserved sediment: in some model realisations, even with preservation as low as 40%, the correct forcing signal can be detected accurately while, conversely, sections with preservation as high as 90% can have poor signal preservation. The reverse can also be true in other models. It is therefore concluded that distinguishing allocyclic and autocyclic forcing in shallow marine or peritidal carbonate successions is likely to be extremely difficult except in cases of extraordinary sedimentary preservation and dating accuracy.

Hill, Jon; Wood, Rachel; Curtis, Andrew; Tetzlaff, Daniel M.

2012-11-01

360

RELATIONSHIPS BETWEEN RESIDUES OF AHR AGONISTS IN FISH AND CONCENTRATIONS IN WATER AND SEDIMENTS  

EPA Science Inventory

Relationships between Residues of AhR Agonists in Fish and Concentrations in Water and Sediment. Cook, PM*, Burkhard, LP, Mount, DR, US-EPA, NHEERL, MED, Duluth, MN. The bioaccumulation visualization approach of Burkhard et al. (2002) can be effectively used to describe the bioa...

361

Changes in water and sediment bacterial community structure in a lake receiving acid mine drainage  

Microsoft Academic Search

Water and sediment bacterial communities in a freshwater impoundment were studied over a 13-month period for stress-related responses to a point source of acid mine drainage (AMD). Comparisons of community structure were made on collections taken at the mouth of the acid stream, at a point 2 km downstream, and at the mouth of an uncontaminated stream. Monthly measurements of

Raymond A. Wassel; Aaron L. Mills

1983-01-01

362

Heavy Metals In Water, Suspended Particles, Sediments And Aquatic Plants Of Habbaniya Lake, Iraq  

Microsoft Academic Search

Seasonal samples were taken from four selected stations on the Habbaniya lake, middle of Iraq during 1997, to study six heavy metals (Cu, Cd, Pb, Ni, Mn, and Zn), in water suspended particles, sediments and aquatic plants. Five plant species were collected, represented the most dominant in the lake, namely Myriophyllum verticillatum, Potamogeton crispus, P. pectinatus, Ceratophyllum demersum and Vallisnaria

Hussain A. Al-Saadi; Ali A. Al-Lami; Falih A. Hassan; Amer A. Al-Dulymi

2002-01-01

363

KINETIC STUDIES OF THE REDUCTION OF AROMATIC AZO COMPOUNDS IN ANAEROBIC SEDIMENT/WATER SYSTEMS  

EPA Science Inventory

The reductive transformation of azobenzene and selected derivatives was investigated in anaerobic sediment/water systems. The azo compounds exhibited pseudo-first-order disappearance kinetics through at least three half-lives. The reduction kinetics of these compounds was studied...

364

Incidence of mussel culture on biogeochemical fluxes at the sediment-water interface  

Microsoft Academic Search

Upward nutrient fluxes at the sediment-water interface were studied in a mussel farming zone (Carteau, Gulf of Fos, France) in order to estimate the impact of organic matter input from biodeposition. Nitrate, nitrite, ammonia, silicate, phosphate and oxygen were measured. Fluxes were estimated by means of polyacrylate benthic chambers placed at sites located under (UM) and outside (OM) the rope

Dominique Baudinet; Elizabeth Alliot; Brigitte Berland; Christian Grenz; Marie-Reine Plante-Cuny; Raphaël Plante; Chantal Salen-Picard

1990-01-01

365

Eos, Vol. 91, No. 29, 20 July 2010 Water and wet sediments under ice sheets  

E-print Network

Eos, Vol. 91, No. 29, 20 July 2010 Water and wet sediments under ice sheets can play an important role in regulating the rate of ice stream flow in Antarctica, particularly over short time scales. Indeed, the discharge of subglacial lakes has been linked to an increase in ice velocity of Byrd Glacier

Priscu, John C.

366

Selenium in water, sediment, plants, invertebrates, and fish in the Blackfoot River drainage  

USGS Publications Warehouse

Nine stream sites in the Blackfoot River watershed in southeastern Idaho were sampled in September 2000 for water, surficial sediment, aquatic plants, aquatic invertebrates, and fish. Selenium was measured in these aquatic ecosystem components, and a hazard assessment was performed on the data. Water quality characteristics such as pH, hardness, and specific conductance were relatively uniform among the nine sites examined. Selenium was elevated in water, sediment, aquatic plants, aquatic invertebrates, and fish from several sites suggesting deposition in sediments and food web cycling through plants and invertebrates. Selenium was elevated to concentrations of concern in water at eight sites (>5 ??g/L), sediment at three sites (>2 ??g/g), aquatic plants at four sites (>4 ??g/g), aquatic invertebrates at five sites (>3 ??g/g), and fish at seven sites (>4 ??g/g in whole body). The hazard assessment of selenium in the aquatic environment suggested low hazard at Sheep Creek, moderate hazard at Trail Creek, upper Slug Creek, lower Slug Creek, and lower Blackfoot River, and high hazard at Angus Creek, upper East Mill Creek, lower East Mill Creek, and Dry Valley Creek. The results of this study are consistent with results of a previous investigation and indicate that selenium concentrations from the phosphate mining area of southeastern Idaho were sufficiently elevated in several ecosystem components to cause adverse effects to aquatic resources in the Blackfoot River watershed. ?? 2004 Kluwer Academic Publishers.

Hamilton, S.J.; Buhl, K.J.

2004-01-01

367

Diagenetic processes near the sediment-water interface of Long Island Sound. II. Fe and Mn  

SciTech Connect

The chemical diagenesis of iron and mangnese in the near-shore sediments of Long Island Sound are examined. Particular emphasis is place on quantifying the physical and biological transport-reaction processes controlling both the distribution of these metals within the upper few decimeters of a deposit and the exchange of their soluble forms with overlying water.

Aller, R.C.

1980-12-01

368

ASSESSING WATER QUALITY CHANGES IN THE LAKES OF THE NORTHEASTERN UNITED STATES USING SEDIMENT DIATOMS  

EPA Science Inventory

Diatom assemblages were selected as indicators of lake condition and to assess historical lake water quality changes in 257 lakes in the northeastern United States. The "top" (surface sediments, present-day) and "bottom" (generally from >30 cm deep, representing historical condit...

369

Evaluation Of Selected Sorption Materials For Capping Mercury-Contaminated Fresh Water Sediments  

EPA Science Inventory

Fate and transport of mercury (Hg) and methylmercury (MeHg) within the aquatic environment involves many complex and interconnected pathways. MeHg is formed mainly at the sediment-water interface, just below which there is a transition from oxic to anoxic conditions. The format...

370

Bench-Scale Investigation Of Mercury Phytoremediation By Water Hyacinths ( Eichhornia crassipes ) In Heavily Contaminated Sediments  

EPA Science Inventory

Phytoremediation has the potential to be implemented at mercury (Hg) and methylmercury (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-associat...

371

Survey of Contaminants in Suspended Sediment and Water in the Fraser River Basin  

E-print Network

#12;Survey of Contaminants in Suspended Sediment and Water in the Fraser River Basin - ­ -- -- ­ -- - 7 The Fraser River Basin M. Sekela, R Brewer, C. Baldazzi, G. Moyle and T. Tuominen Science Division River and supporting the field operations. We are greatly indebted to C. MacDonal~ G. McGdlivary, I

372

Levels of chlordane in water and sediment of rivers around Saga City, Japan  

Microsoft Academic Search

In the present study, we investigated the residues of chlordane in our living environments which are Saga city and its surroundings. Saga city is located in the middle of a paddy field sandwitched between a mountain district in the north and Ariake sea in the south. In this paper, we report the levels of chlordane in water and sediment of

Yukio Hirai; Katsumaro Tomokuni

1989-01-01

373

Internal Winds in Water Lilies: An Adaptation for Life in Anaerobic Sediments  

Microsoft Academic Search

The network of internal gas spaces in the yellow water lily constitutes a pressurized flow-through system which forces oxygen to the roots and rhizome buried in the anaerobic sediment. By the purely physical processes of thermal transpiration and hygrometric pressure, several liters of air per day enter the young, newly emerged leaves of Nuphar luteum against a small pressure gradient.

John W. H. Dacey

1980-01-01

374

Application of Toxicity Identification Evaluation Techniques to Pore Water from Buffalo River Sediments  

Microsoft Academic Search

To identify contaminants responsible for toxicity of sediments from the Buffalo River, toxicity identification evaluations (TIEs) were conducted with interstitial (pore) water from several sites. Initial toxicity of the samples was determined using fathead minnows (Pimephales promelas) and the cladoceran Ceriodaphnia dubia, and TIE analyses were conducted with the most sensitive of the two species at a particular site. Fathead

Gerald T. Ankley; Mary K. Schubauer-Berigan; Joseph R. Dierkes

1996-01-01

375

Pore-water chemistry in mangrove sediments: relationship with species composition and  

E-print Network

Pore-water chemistry in mangrove sediments: relationship with species composition and developmental and solid phase sulphide concentration were investigated in a range of mangrove communities along the coast Avicennia, Rhizophora and mixed mangrove stands at different stages of plant development. Mangrove

Boyer, Edmond

376

Heavy metals in water, sediments and submerged macrophytes in ponds around the Dianchi Lake, China.  

PubMed

Through retaining runoff and pollutants such as heavy metals from surrounding landscapes, ponds around a lake play an important role in mitigating the impacts of human activities on lake ecosystems. In order to determine the potential for heavy metal accumulation of submerged macrophytes, we investigated the concentrations of 10 heavy metals (i.e., As, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, and Zn) in water, sediments, and submerged macrophytes collected from 37 ponds around the Dianchi Lake in China. Our results showed that both water and sediments of these ponds were polluted by Pb. Water and sediments heavy metal concentrations in ponds received urban and agricultural runoff were not significantly higher than those in ponds received forest runoff. This result indicates that a large portion of heavy metals in these ponds may originate from atmospheric deposition and weathering of background soils. Positive relationships were found among heavy metal concentrations in submerged macrophytes, probably due to the coaccumulation of heavy metals. For most heavy metals, no significant relationships were found between submerged macrophytes and their water and sediment environments. The maximum concentrations of Cr, Fe and Ni in Ceratophyllum demersum were 4242, 16,429 and 2662mgkg(-1), respectively. The result suggests that C. demersum is a good candidate species for removing heavy metals from polluted aquatic environments. PMID:25011115

Wang, Zhixiu; Yao, Lu; Liu, Guihua; Liu, Wenzhi

2014-09-01

377

Water and sediment quality in Qinghai Lake, China: a revisit after half a century.  

PubMed

Qinghai Lake, situated on the Qinghai-Tibet plateau, is the largest lake in China. In this study, the water and sediment quality were investigated in Qinghai Lake, three sublakes, and five major tributaries. Both Na(+) and Cl(-) were found to be the major ions present in Qinghai Lake and the three sublakes, while Ca(2+) and HCO(3-) dominated the tributaries. Compared with historical data from the 1960s, the concentrations of NH4(+), NO3(-), and soluble reactive silica have increased considerably, likely caused by increased human activities in the area. Compared to the historical data, chemical oxygen demand has increased and lake water transparency has decreased, likely related to an increase in nutrient levels. Relatively high concentrations of total nitrogen (TN) and total phosphorus (TP) were observed in Qinghai Lake sediments, although P fraction types and low water concentrations of these two indicate low possibility of transfer into the water column. The ratios of C/N suggest that the organic matter in the sediments are primarily from autochthonous sources. TN and total organic carbon in the sediment cores increased slowly up the core while TP and total inorganic carbon have been fairly constant. PMID:24213639

Ao, Hongyi; Wu, Chenxi; Xiong, Xiong; Jing, Liandong; Huang, Xiaolong; Zhang, Kai; Liu, Jiantong

2014-04-01

378

Other water pollution. [Nonpoint sources, primarily agricultural sediment and urban runoff  

Microsoft Academic Search

Only half the water pollutants are estimated by the Environmental Protection Agency (EPA) to originate at point sources, while the other half result from diverse nonpoint sources that are hard to identify and hard to control. Nonpoint sources are primarily one of eight types of runoff, with the major volume attributed to agricultural sediment and urban runoff. Urban stormwater runoff

1978-01-01

379

Sediment Quality in Near Coastal Waters of the Gulf of Mexico: Influence of Hurricane Katrina  

EPA Science Inventory

The results from this study represent a synoptic analysis of sediment quality in coastal waters of Lake Pontchartrain and Mississippi Sound two months after the landfall of Hurricane Katrina. Post-hurricane conditions were compared to pre-hurricane (2000-2004) conditions, for se...

380

Biodegradation screening of chemicals in an artificial matrix simulating the water-sediment interface.  

PubMed

Biodegradation is the most important attenuation process for most of organic chemicals in the environment. This process decides whether the organic substance itself or its degradation products rests in the environment and should be considered for a further risk assessment. This work presents the development of a water sediment screening test, based on OECD guideline 308, with a high significance to environmental conditions and with a good reproducibility and consistency of results. The increased reproducibility was achieved by creating an artificial and standardized medium, based on the existing OECD guidelines OECD 302C, 301D and 218. Each test consisted of five different series: blank, quality control, test, toxicity control and abiotic control. Biodegradation was assessed by measurement of pressure difference in closed vessels using the OxiTop(®) system. Aniline, diethylene glycol and sodium acetate were used to optimize and validate test conditions. Additionally, two pharmaceuticals: Acetaminophen and ciprofloxacin (CIP) were tested as an example of possible test application. Acetaminophen was mainly removed from the system by biodegradation whereas CIP was removed from water phase by sorption onto sediment. Water sediment test proved to be a promising tool for the biodegradation investigation of chemicals in the water-sediment interface. PMID:25460767

Baginska, Ewelina; Haiss, Annette; Kümmerer, Klaus

2015-01-01

381

FIELD DESCRIPTION Water Oil/Tar Sediment Tissue STUDYNAME Study Name X X X X  

E-print Network

FIELD DESCRIPTION Water Oil/Tar Sediment Tissue STUDYNAME Study Name X X X X QCBATCH Laboratory analysis Group ID X X X X EXSAMPID Investigator's sample identifier X X X X SAMPDATE Date sample collected as YYYYMMDD X X X X SAMPTIME Time sample collected as HH:MM X X X X SITEID Site identifier X X X X STUDYID

382

An assessment of five Australian polychaetes and bivalves for use in whole-sediment toxicity tests: toxicity and accumulation of copper and zinc from water and sediment.  

PubMed

The suitability of two polychaete worms, Australonereis ehlersi and Nephtys australiensis, and three bivalves, Mysella anomala, Tellina deltoidalis, and Soletellina alba, were assessed for their potential use in whole-sediment toxicity tests. All species except A. ehlersi, which could not be tested because of poor survival in water-only tests, survived in salinities ranging from 18 per thousand to 34 per thousand during the 96-hour exposure period. No mortality was observed in any of the species exposed to sediment compositions ranging from 100% silt to 100% sand for 10 days, thus demonstrating the high tolerance of the five species to a wide range of sediment types. All species showed decreased survival after exposure to highly sulfidic sediments in 10-day whole-sediment tests. In 96-hour water-only tests, survival decreased, and copper accumulation in body tissues increased with exposure to increasing copper concentration for all species except A. ehlersi, which again could not be tested because of its poor survival in the absence of sediment. S. alba and T. deltoidalis were the most sensitive species to aqueous copper (LC50s of 120 and 150 microg Cu/L, respectively). All species tested were relatively insensitive to dissolved zinc up to concentrations of approximately 1,000 microg/L. In addition and with the exception of N. australiensis, all species accumulated significant levels of zinc in their body tissues. Whole-sediment tests were conducted over a 10-day period with copper-spiked (1,300 microg/g) and zinc-spiked (4,000 microg/g) sediments equilibrated for sufficient time to ensure that pore water metal concentrations were well below concentrations shown to have any effect on organisms in water-only tests. Survival was decreased in the bivalves T. deltoidalis and S. alba after exposure to copper-spiked sediments, and all species-except T. deltoidalis, in which 100% mortality was observed-accumulated copper in their tissues. Exposure to zinc-spiked sediments significantly decreased the survival of only one species, T. deltoidalis. Both polychaetes appeared to regulate concentrations of zinc in their body tissues with no significant uptake of zinc occurring from the sediment phase. Of the five species assessed in this study, T. deltoidalis was found to be the most sensitive to copper- and zinc-contaminated sediments, and based on commonly used selection criteria (ASTM 2002a, ASTM 2002b, ASTM 2002c) is recommended for development as test species in whole-sediment toxicity tests. PMID:15386125

King, C K; Dowse, M C; Simpson, S L; Jolley, D F

2004-10-01

383

Comprehensive sediment toxicity assessment of Hessian surface waters using Lumbriculus variegatus and Chironomus riparius.  

PubMed

The objective of this study was a sediment assessment of predominantly small rivers in the German federal state of Hesse. For this purpose, sediment samples were taken at 50 study sites with different contamination levels. The benthic invertebrates Chironomus riparius (Diptera) and Lumbriculus variegatus (Oligochaeta) were used as test species and exposed to whole sediments in chronic laboratory experiments. The bioassays were carried out on the basis of OECD guidelines 218 and 225 for the testing of chemicals. For about 50 % of the study sites chemical analytical data for pollutants from environmentally important substance classes like metals, polycyclic aromatic hydrocarbons, polychlorinated biphenyls, and organotin compounds were available. These data were used to analyze correlations between effects in the bioassays and measured chemical contaminations at sampling sites. For 22 % of the sediments ecologically relevant adverse effects were observed. In the majority of these cases effects occurred in only one of the biotests, and only one sediment sample exerted a negative effect on both test organisms. There was no significant correlation between biological responses and chemical data considering substance classes. However, there was a weak positive correlation between arsenic concentration and both worm number and worm biomass as well as a weak positive correlation between single PAHs and worm biomass. In some sediment tests elevated ammonia concentrations occurred in the overlying water so that an influence of these partially toxic concentrations on the test results cannot be ruled out. PMID:22375534

Galluba, Simone; Oetken, Matthias; Oehlmann, Jörg

2012-01-01

384

Aluminum forms in stream sediment: Relation to bedrock geology and water chemistry  

SciTech Connect

Longitudinal gradients in sediment and water chemistry were characterized in a high elevation stream in the southern Appalachian Mountains, USA, to elucidate the geochemical behavior of aluminum across gradients in pH (4.5 to 6.5) and elevation (1120 to 1895 m). Observed gradients are driven in part by the presence of pyritic bedrock, which occurs at higher elevations and yields acidity when exposed to oxidation by landslide activity. Exchangeable Al in sediment (estimated using potassium chloride) varied in response to monomeric Al in streamwater and thus decreased downstream. Organic Al in sediment (estimated using sodium pyrophosphate) did not vary in proportion to the organic carbon content of sediment. Amorphous Al in sediment (estimated as the difference between oxalate- and pyrophosphate-extractable Al) and Al extractable with acidified streamwater (pH 4.5) was lowest at the more acidic sites. These results suggest that increases in soluble Al in downstream reaches during episodic pH depressions could be due in part to the release of adsorbed and/or precipitated Al in sediment.

Turner, R.R.; Bogle, M.A.; Zeiler, M.A.; Mulholland, P.J.; Elwood, J.W.; Cook, R.B.

1987-01-01

385

Halogens in the Dry Valleys Lakes, Antarctica: dynamic cycling between water, sediment, and cryogenic evaporites  

NASA Astrophysics Data System (ADS)

Many of the McMurdo Dry Valleys lakes of Antarctica exhibit saline to hypersaline bottom waters whose chemistry is distinct from that of sea water. The source and relative abundance of dissolved Cl, Br, and I in these unusual waters has been modified by several potential processes including: seawater incursions, water- rock interactions, microbial scavenging, glacial melting and precipitation, and atmospheric deposition. Since all of these processes are affected by both long-term and short-term climate change, lake waters and the salts that are deposited around them provide sensitive indicators of lake dessication and refilling in the past. We present elemental analyses, not only of the lake water, but also of bottom sediments and cryogenic evaporites recovered from the Dry Valleys. XRD analyses indicate that gypsum and antarcticite are precipitated around saline lakes presently situated more than 40 km from the ocean (Vanda, Don Juan, Joyce), while mirabilite is found near small pools in the Garwood Valley, only a few km from the ocean. Lake water enrichments in Ca and Cl, relative to Na suggest that either dissolution of gypsum and antarcticite has occurred in Don Juan Pond and Lake Vanda, or that these two small bodies of water previously lost sodium to mirabilite formation. Lakes Fryxell and Joyce, as well as waters in Garwood Valley show near-sea water ratios. Dissolved iodine, and to a lesser extent bromine, are commonly associated with diagenesis of marine organic matter in regions of high productivity, so it is surprising that the Dry Valleys lake waters are enriched in these two elements. These enrichments are also apparent in pore fluids of shallow sediments on the lake bottoms. In addition, the sediments themselves are highly enriched in iodine in the upper 5 cm (up to 77 ppm). This is likely due to remobilization of dissolved iodide, which is mobile in reduced form, but becomes fixed as adsorbed or organic iodine upon diffusing into shallow oxic sediments. Temporal changes in ice cover, and oxidation state of the deeper lake waters may be reflected in the efficiency by which dissolved iodide is released from these deep sediments and diffuses up through the water column.

Snyder, G. T.; Dowling, C. B.; Harbert, A.; Lu, H.; Lyons, W. B.; Welch, K. A.

2006-12-01

386

Bathymetric survey by depth-sonar and lake sediment coring by Beeker sampler to identify sediment budgets and siltation rates of small reservoirs  

Microsoft Academic Search

The construction of small dams is a common practice for dealing with erratic and unevenly distributed rainfalls in semi-arid environments. Dams have the function to store rainfall and runoff water from the catchment and serve as water storage for domestic use, irrigation, and stock watering. At the same time, they are potential sinks for upstream sediments. Soil particles accumulating in

A. C. Brunner

387

Solar heating and domestic hot water system installed at Kansas City, Fire Station, Kansas City, Missouri. Final report  

SciTech Connect

This document is the final report of the solar energy heating and hot water system installed at the Kansas City Fire Station, Number 24, 2309 Hardesty Street, Kansas City, Missouri. The solar system was designed to provide 47 percent of the space heating, 8800 square feet area and 75 percent of the domestic hot water (DHW) load. The solar system consists of 2808 square feet of Solaron, model 2001, air, flat plate collector subsystem, a concrete box storage subsystem which contains 1428 cubic feet of 1/2 inch diameter pebbles weighing 71 1/2 tons, a DHW preheat tank, blowers, pumps, heat exchangers, air ducting, controls and associated plumbing. Two 120-gallon electric DHW heaters supply domestic hot water which is preheated by the solar system. Auxiliary space heating is provided by three electric heat pumps with electric resistance heaters and four 30-kilowatt electric unit heaters. There are six modes of system operation. This project is part of the Department of Energy PON-1 Solar Demonstration Program with DOE cost sharing $154,282 of the $174,372 solar system cost. The Final Design Review was held March 1977, the system became operational March 1979 and acceptance test was completed in September 1979.

None

1980-07-01

388

Development of a gas backup heater for solar domestic hot-water systems. Final report, April 1978-April 1980  

SciTech Connect

A comprehensive program was undertaken to develop a unique gas fired backup for solar domestic hot water systems. Detailed computer design tools were written. A series of heat transfer experiments were performed to characterize the performance of individual components. A full scale engineering prototype, including the solar preheat tank and solar heat exchanger, was designed, fabricated and subjected to limited testing. Firing efficiency for the backup system was found to be 81.4% at a firing rate of 50,000 Btu/h. Long term standby losses should be negligible.

Morrison, D.J.; Grunes, H.E.; de Winter, F.; Armstrong, P.R.

1980-06-01

389

Distribution of total mercury and methyl mercury in water, sediment, and fish from South Florida estuaries  

USGS Publications Warehouse

Concentrations of total mercury and methyl mercury were determined in sediment and fish collected from estuarine waters of Florida to understand their distribution and partitioning. Total mercury concentrations in sediments ranged from 1 to 219 ng/g dry wt. Methyl mercury accounted for, on average, 0.77% of total mercury in sediment. Methyl mercury concentrations were not correlated with total mercury or organic carbon content in sediments. The concentrations of total mercury in fish muscle were between 0.03 and 2.22 (mean: 0.31) ??g/g, wet wt, with methyl mercury contributing 83% of total mercury. Methyl mercury concentrations in fish muscle were directly proportional to total mercury concentrations. The relationship of total and methyl mercury concentrations in fish to those of sediments from corresponding locations was fish-species dependent, in addition to several abiotic factors. Among fish species analyzed, hardhead catfish, gafftopsail catfish, and sand seatrout contained the highest concentrations of mercury. Filtered water samples from canals and creeks that discharge into the Florida Bay showed mercury concentrations of 3-7.4 ng/L, with methyl mercury accounting for <0.03-52% of the total mercury. Consumption of fish containing 0.31 ??g mercury/g wet wt, the mean concentration found in this study, at rates greater than 70 g/day, was estimated to be hazardous to human health.

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

1998-01-01

390

Distribution of total mercury and methyl mercury in water, sediment, and fish from south Florida estuaries.  

PubMed

Concentrations of total mercury and methyl mercury were determined in sediment and fish collected from estuarine waters of Florida to understand their distribution and partitioning. Total mercury concentrations in sediments ranged from 1 to 219 ng/g dry wt. Methyl mercury accounted for, on average, 0.77% of total mercury in sediment. Methyl mercury concentrations were not correlated with total mercury or organic carbon content in sediments. The concentrations of total mercury in fish muscle were between 0.03 and 2.22 (mean: 0.31) micrograms/g, wet wt, with methyl mercury contributing 83% of total mercury. Methyl mercury concentrations in fish muscle were directly proportional to total mercury concentrations. The relationship of total and methyl mercury concentrations in fish to those of sediments from corresponding locations was fish-species dependent, in addition to several abiotic factors. Among fish species analyzed, hardhead catfish, gafftopsail catfish, and sand seatrout contained the highest concentrations of mercury. Filtered water samples from canals and creeks that discharge into the Florida Bay showed mercury concentrations of 3-7.4 ng/L, with methyl mercury accounting for < 0.03-52% of the total mercury. Consumption of fish containing 0.31 microgram mercury/g wet wt, the mean concentration found in this study, at rates greater than 70 g/day, was estimated to be hazardous to human health. PMID:9469852

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

1998-02-01

391

Enhancement of anaerobic ammonium oxidation in lake sediment by applying drinking water treatment residuals.  

PubMed

In this study, the effect of drinking water treatment residuals (WTRs), non-hazardous byproducts from drinking water treatment plants, on anaerobic ammonium oxidation (anammox) in lake sediments were investigated, qualitatively and quantitatively based on enrichment tests. The results suggested that after the enrichment, anammox were strengthened significantly in enriched sediments with no WTRs (ESNW) and with WTRs (ESW). Comparatively, anammox bacteria in ESW were more aggregated than ESNW. The activity (9.2 nmol g(-1)h(-1)) and abundance (9.8×10(7)copies g(-1)) of anammox bacteria in ESW were also higher than ESNW (6.1 nmol g(-1)h(-1)and 8.9×10(7) copies g(-1)). Further analysis suggested that after enrichment, anammox bacteria in sediments were phylogenetically more distant from Candidatus Kuenenia; anammox bacteria in ESW were closely related to Candidatus Brocadia. Overall, WTRs promoted aggregation, strengthened activity and increased abundance of anammox bacteria in lake sediments. Therefore, WTRs can enhance anammox in lake sediments. PMID:23800683

Wang, Ziyuan; Wang, Changhui; Wang, Zhixin; Pei, Yuansheng

2013-08-01

392

Toxicity of sediments and interstitial waters form the Southern California Bight  

SciTech Connect

The toxicity of 72 sediment samples collected during the EMAP Southern California Bight Pilot Project (SCBPP) was measured. Sediments from the mainland shelf between Point Conception and the Mexican border were collected from various depths and tested for toxicity using two methods. The toxicity of bulk sediment was measured using a 10-day amphipod (Ampelisca abdita) survival test. Interstitial water was also extracted from the samples and tested for toxicity using a 72-hour sea urchin (Strongylocentrotus purpuratus) embryo development test. Amphipod survival was high (> 80%) at all stations tested, although several sites near large sewage outfalls had statistically significant reductions in survival. No interference related to grain size variation was observed with the amphipod test. Most of the interstitial water samples produced abnormal sea urchin embryo development. Effects were not related to the presumed level of sediment contamination, but rather to ammonia concentration in virtually all cases. The impacts of sample handling procedures and ammonia on sediment toxicity data interpretation will be discussed.

Bay, S.; Greenstein, D.; Brown, J.; Jirik, A. [Southern California Coastal Water Research Project, Westminster, CA (United States)

1995-12-31

393

Laboratory Modeling of Self-Formed Leveed Channels From Sediment-Laden Flows Entering Still Water  

NASA Astrophysics Data System (ADS)

Self-formed leveed channels constructed by deposition of suspended sediment from sediment-laden flows entering still water are common features in nature. Such channels drive delta progradation, develop at tidal inlets and occur where mainstem river flows empty into oxbows and blocked valley lakes. Presently there is no theory for the formation of such channels. This lack of theory is partly due to a lack of field or laboratory studies that provide insight about the mechanism controlling these self-formed, propagating channels. The creation of such features in the laboratory, have proved illusive to date. Our ongoing experiments aimed at modeling the formation of floodplain tie channels provide insight into the necessary conditions for levee formation and channel growth. Under conditions of steady water discharge, constant sediment feed rate, unimodal sediment distribution and invariant basin stage we are able to create subaqueous lateral bars (submerged levees) along the margins of a sediment laden jet. Our results highlight the sensitivity of channel formation to issues of scaling and experimental design. In the laboratory, levee formation has only been possible with the use of plastic particles (specific gravity ~1.5); complete bed alluviation and dune formation results from the use of particles with specific gravities of ~ 2.65 across a range grain diameters and shapes. We hypothesize this effect is related to high entrainment thresholds relative to suspension thresholds of small (< 100 mm) natural particles under conditions of reduced turbulence in laboratory scaled flows. Additionally, both the width to depth ratio and the form of the outlet channel introducing the sediment laden flow into the experimental basin exert a strong control on sedimentation pattern and levee growth. Continuing experiments are focused on generating emergent channel levees and a basin ward propagation of the channel by adjusting the form of the feed channel, varying basin stage, and the use of unsteady discharge.

Rowland, J. C.; Dietrich, W. E.

2004-12-01

394

Dynamic modelling of passive margin salt tectonics: effects of water loading, sediment properties and  

E-print Network

continental margin to include the e¡ects of submarine water loading and pore £uid pressure. Seaward thinning sediments above aweak salt layer produce a pressure gradient that induces Poiseuille £ow in the viscous salt by Couette £ow in the underlying salt.The e¡ects of water: (i) increase solid and £uid pressures

Beaumont, Christopher

395

Heavy metals in water, sediment and tissues of Liza saliens from Esmoriz-Paramos lagoon, Portugal.  

PubMed

Esmoriz-Paramos lagoon is an ecosystem of great ecological importance that is located on the northwest coast of Portugal and has been degraded as a result of industrial and anthropogenic activities. Concentrations of heavy metals (Cr, Cu, Pb and Zn) were measured in water, sediment and in tissues (liver and muscle) of Liza saliens, which is the dominant fish from the lagoon. Comparisons between metal concentrations in water and sediments were made with those in tissues of fish caught at the lagoon. Metals in water were quantified predominantly bound to particulate and equalled or exceeded the limit of chronic reference values. Metal concentrations in sediments varied among sampled sites. The relative order of concentrations was "Zn > Cu approximately Pb > Cr" the same pattern observed for metals in water. Metals in fish tissues showed higher concentrations in liver (262 mg CuxKg(-1) and 89 mg ZnxKg(-1)) than in muscle (<3 mg CuxKg(-1) and 26 mg ZnxKg(-1)), while Pb and Cr were not detected. These results suggest that Cu and Zn are the metals of major concern in the lagoon. Mullet detritivorous feeding habits, bioaccumulation pattern and the high sediment metals concentrations relative to the water suggest that sediments can be the most important source of contamination in this ecosystem. The positive relationship found between Cu in liver and fish length demonstrates that time of exposure is a crucial factor in bioaccumulation. Condition indices (K and HSI) in mullets from the lagoon were higher compared to mullets from sea, suggesting abnormal condition in the lagoon population. We conclude that metals chronic exposure in the lagoon can impose considerable fish stress. The results also show that the lagoon is an area of environmental concern. PMID:17447151

Fernandes, C; Fontaínhas-Fernandes, A; Cabral, D; Salgado, M A

2008-01-01

396

Mineral composition and heavy metal contamination of sediments originating from radium rich formation water.  

PubMed

Radium rich formation water is often associated with fossil fuels as crude oil, natural gas and hard coal. As a result of fossil fuels exploitation high amount of such water is released into environment. In spite of the high radium content such waters create a serious radiation risk neither to humans nor biota directly. First and foremost due to very high mineralization they are not drinkable at all. But after discharge chemical and physical conditions are substantially changed and sediments which additionally concentrated radium are arising. Due to features of technological processes such phenomenon is very intensive in underground coal mining where huge volume of such water must be pumped into surface in order to keep underground galleries dry. Slightly different situation occurs in oil rigs, but finally also huge volume of so called process water is pumped into environment. Regardless their origin arising sediments often contain activity concentration of radium isotopes exceeding the clearance levels set for naturally occurring radioactive materials (NORM) (Council Directive, 2013). The analysis of metals and minerals content showed that besides radioactivity such sediments contain high amount of metals geochemically similar to radium as barium, strontium and lead. Correlation analysis proved that main mechanism leading to sediment creation is co-precipitation radium with these metals as a sulfate. The absorption on clay minerals is negligible even when barium is not present in significant quantities. Owing to very low solubility of sulfates radium accumulated in this way should not migrate into environment in the neighborhood of a site where such sediment were deposited. PMID:25434264

Bzowski, Zbigniew; Michalik, Bogus?aw

2015-03-01

397

Sediment-pore water interactions controlling cementation in the NanTroSEIZE drilling transects  

NASA Astrophysics Data System (ADS)

One goal of the Nankai Trough Seismogenic Zone Experiment (NanTroSEIZE) is to understand how changes in subducting sediment control the transition from aseismic to seismogenic behavior in subduction zones. In the sediment entering the Nankai subduction zone, dramatic changes in physical and chemical properties occur across a diagenetic boundary; they are thought to affect sediment strength and deformation. The dissolution of disseminated volcanic ash and precipitation of silica cement may be responsible for these changes in physical properties, but the mechanism controlling cementation was unclear (Spinelli et al., 2007). In this study, we used CrunchFlow (Steefel, 2009) to simulate chemical reactions and fluid flow through 1-D sediment columns at Integrated Ocean Drilling Program (IODP) sites on the incoming plate in Nankai Trough. The simulations include the thermodynamics and kinetics of sediment-water interactions, advection of pore water and sediment due to compaction, and multi-component diffusion in an accumulating sediment column. Key reactions in the simulations are: ash dissolution, amorphous silica precipitation and dissolution, and zeolite precipitation. The rate of ash decomposition was constrained using Sr isotope data of Joseph et al. (2012). Our model reproduces the distinct diagenetic boundary observed in sediment and pore water chemistry, which defines two zones. Above this boundary (zone 1), dissolved and amorphous silicate contents are high and the potassium concentration remains near seawater values or gradually decreases toward the boundary. Below the boundary, both dissolved and amorphous silicate content drop rapidly, concomitant with a decrease in dissolved potassium. Our model shows that these changes in the system are driven by formation of clinoptilolite in response to changes in pore fluid pH. The low pH values (<7.6) above the diagenetic boundary accelerate ash decomposition and maintain clinoptilolite slightly undersaturated. The dissolved silicate released from ash alteration precipitates as cement, inhibiting consolidation. At or below the boundary, the increase in pH (>8.0), leads to oversaturation (and precipitation) of clinoptilolite. Strong demand of dissolved silicate due to clinoptilolite formation soon depletes the dissolved potassium and silicate; ash and silicate cement are forced to dissolve. The exact set of reactions resulting on the observed pH increase is still unclear, but it likely involves the carbon system. It is noteworthy that the diagenetic boundary at all sites in the incoming plate occurs at the same thermal maturity of the sediments (TTI=0.025), similar to observations on onshore sequences in Japan (Sasaki, 1986).

Hong, W.; Spinelli, G. A.; Torres, M. E.

2012-12-01

398

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

PubMed

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 and industrial human activities have led to dramatic changes in the Nile River chemistry. Nowadays, the Nile River has the highest dissolved salt content among the major African rivers. Dissolved transport is a major process for Ca, K, Sr, Zn, Cu, Ni and V. Manganese, Fe and Cr are mainly carried by suspended matter. The Nile suspended matter is exhausted in almost all elements studied (except for Mn) compared to the world average river suspended matter. Along the course of the river, the distribution of elements in the suspended matter and sediments is generally controlled by natural processes: the relative importance of elemental transport phases; and the oxidation, precipitation and sedimentation of mineral species through the varying physico-chemical conditions of the environment. Pollution input in the Nile particulate load is not major, as compared to the natural inputs. Eight genetic particle types describe the composition of the Nile suspended matter and sediments: (1) biogenous-aeolian (or silica); (2) terrigenous (Fe-aluminosilicate); (3) authigenic (calcium carbonate); (4) biogenous (apatite); (5) authigenous-terrigenous (Fe-oxyhydroxide-montmorillonite); (6) diagenetic (iron-sulfide); (7) terrigenous (titanium oxide); (8) authigenous (Mn-Fe-oxyhydroxide). PMID:9241870

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

1997-08-18

399

Short-term water and suspended-sediment fluctuations in a Louisiana marsh  

USGS Publications Warehouse

To determine the timing of and driving forces for sediment suspension and deposition and the effect of impoundment, three self-recording instrument packages were deployed in a section of Louisiana marsh. Two of the packages went into an impoundment and one into an adjacent open, or control, area. A data logger in the package controlled sensors to measure water level, velocity, salinity, and temperature and suspended sediment concentration. At one impoundment site and the control site, weather stations recorded wind speed and direction. This paper describes and discusses the results.

Dingler, John R.

1993-01-01

400

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

SciTech Connect

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 wide range of sediment types. Six separate experiments were conducted in which two or three sediments of varying AVS concentration were spiked with a series of concentrations of cadmium, copper, lead, nickel, or zinc or a mixture of four of these metals. The amphipod Ampelisca abdita was then exposed to the sediments in 10-d toxicity tests. Amphipod mortality was sediment dependent when plotted against dry weight metals concentration but was not sediment dependent when plotted against simultaneously extracted metal (SEM)/AVS or interstitial water toxic units (IWTUs). Sediments with SEM/AVS ratios < 1.0 were seldom toxic, while sediments with SEM/AVS ratios > 1.0 were frequently toxic. Similarly, sediments with < 0.5 IWTU were seldom toxic (3.0%), while sediments with > 0.5 IWTU were toxic 94.4% of the time. These results, coupled with results from related studies, demonstrate that an understanding of the fundamental chemical reactions which control the availability of cadmium, copper, lead, nickel, and zinc in sediments can be used to explain observed biological responses. The authors believe that using SEM/AVS ratios and IWTUs allows for more accurate predictions of acute mortality, with better casual linkage to metal concentration, than is possible with sediment evaluation tools which rely on dry weight metal concentrations.

Berry, W.J.; Hansen, D.J.; Boothman, W.S. [Environmental Protection Agency, Narragansett, RI (United States); Mahony, J.D. [Manhattan Coll., New York, NY (United States). Dept. of Environmental Engineering; Robson, D.L. [Rhode Island Dept. of Environmental Management, Providence, RI (United States); Toro, D.M. di [HydroQual, Mahwah, NJ (United States); Shipley, B.P. [Springborn Labs., Wareham, MA (United States); Rogers, B. [Science Applications International Corp., Narragansett, RI (United States); Corbin, J.M. [Texas Natural Resource Conservation Commission, Austin, TX (United States)

1996-12-01

401

Effects of light on sediment nutrient flux and water column nutrient stoichiometry in a shallow lake.  

PubMed

The effects of light and temperature on nutrient cycling (silica (Si), nitrogen (N) and phosphorus (P)) between sediments and water in a shallow eutrophic lake (Loch Leven, Scotland), and consequent effects on water column nutrient stoichiometry, were assessed using a series of intact sediment core incubation experiments. Estimates of actual seasonal dark and light P-fluxes were assessed using 24-h incubations. Sediment-P uptake was observed in spring (7 degrees C) and release in autumn (12 degrees C) and summer (17 degrees C), with the highest release rates ( approximately 17 mgPO4-Pm(-2) sediment surface area d(-1)) occurring in summer. In a longer (21-day) experiment in which the effects of light (light (n=6) and dark (n=6)) and temperature (five 4-day cycles to represent: 7 degrees C-->13 degrees C-->23 degrees C-->13 degrees C-->7 degrees C) on water column nutrient concentrations were assessed, PO(4-)-P, total P (TP), SiO2 and total silica (TSi) concentrations in the water column were all significantly higher under dark conditions (ANOVA, alpha=0.05). NH4-N (ammonium N) water column concentrations were observed to be higher under dark conditions at low temperatures and higher under light conditions following a high-temperature (23 degrees C) treatment. No significant light effects were observed for water column total N (TN) concentration. Flux estimates for all nutrients measured are given. In terms of water column nutrient stoichiometry, TN:TP ratio was significantly higher under light conditions, TSi:TN was significantly lower under light conditions, and TSi:TP did not vary significantly between the dark and light treatments. The main processes acting to regulate diffusive nutrient release appeared to be photosynthetic elevation of bottom water pH and dissolved oxygen concentration (both significantly higher under light conditions) and direct microalgal sequestration. Thus, a feedback mechanism exists in recovering shallow lakes where benthic microalgae can affect the stoichiometry (to favour P/Si limitation) of the plankton, and also of the main source of nutrients back to the sediments via the disproportionate regulation of sediment P, Si and N release. PMID:17923145

Spears, Bryan M; Carvalho, Laurence; Perkins, Rupert; Paterson, David M

2008-02-01

402

Ubiquity and diversity of ammonia-oxidizing archaea in water columns and sediments of the ocean  

PubMed Central

Nitrification, the microbial oxidation of ammonia to nitrite and nitrate, occurs in a wide variety of environments and plays a central role in the global nitrogen cycle. Catalyzed by the enzyme ammonia monooxygenase, the ability to oxidize ammonia was previously thought to be restricted to a few groups within the ?- and ?-Proteobacteria. However, recent metagenomic studies have revealed the existence of unique ammonia monooxygenase ?-subunit (amoA) genes derived from uncultivated, nonextremophilic Crenarchaeota. Here, we report molecular evidence for the widespread presence of ammonia-oxidizing archaea (AOA) in marine water columns and sediments. Using PCR primers designed to specifically target archaeal amoA, we find AOA to be pervasive in areas of the ocean that are critical for the global nitrogen cycle, including the base of the euphotic zone, suboxic water columns, and estuarine and coastal sediments. Diverse and distinct AOA communities are associated with each of these habitats, with little overlap between water columns and sediments. Within marine sediments, most AOA sequences are unique to individual sampling locations, whereas a small number of sequences are evidently cosmopolitan in distribution. Considering the abundance of nonextremophilic archaea in the ocean, our results suggest that AOA may play a significant, but previously unrecognized, role in the global nitrogen cycle. PMID:16186488

Francis, Christopher A.; Roberts, Kathryn J.; Beman, J. Michael; Santoro, Alyson E.; Oakley, Brian B.

2005-01-01

403

Holocene sediment dynamics on a cool-water carbonate shelf: Otway, southeastern Australia  

SciTech Connect

The Otway Shelf is covered by cool waters and veneered by bryozoan-dominated carbonate sediments. Radiocarbon dating and stratigraphy of shelf vibracores and slope gravity cores document late Pleistocene/Holocene deposition. Shelf sediments of the late Pleistocene high-stand are rare, either never having been deposited or having been removed during the following sea-level fall. During the subsequent lowstand the shelf was exposed, facies shifted basinward, and beach/dune complexes were constructed near the shelf edge. The deep shelf was characterized by nondeposition and hardground formation, and the shelf margin became locally erosional. Upper-slope bryozoan/sponge assemblages continued to grow actively, and lower-slope foraminifera and nannofossil ooze was increasingly enriched in hemipelagic terrigenous mud swept off the wide shelf. Coarse shelf debris and lowstand dune sands were erosively reworked and transported onto the upper slope and redistributed to deep-slope aprons during early transgression. The late Quaternary shelf record resembles that of flat-topped, warm-water platforms with Holocene sediment overlying Pleistocene/Tertiary limestone, but for different reasons. The slow growth potential, uniform profile of sediment production and distribution, and inability of constituent organisms to construct rigid frameworks favor maintenance of a shallow ramp profile and makes the cool-water carbonate system an excellent modern analog for interpretation of many ancient ramp successions.

Boreen, T.D.; James, N.P. (Queen's Univ., Kingston, Ontario (Canada))

1993-07-01

404

Water Management and Sediment Control for Urbanizing Areas.  

ERIC Educational Resources Information Center

This handbook, developed for use by the Soil Conservation Service and property owners, land developers, local government agencies, and consulting firms, is designed to provide information on water management and minimizing erosion on land undergoing development in urban areas. The standards and specifications listed in this handbook are to provide…

Soil Conservation Service (USDA), Columbus, OH.

405

The effect of water harvesting techniques on runoff, sedimentation, and soil properties.  

PubMed

This study addressed the hydrological processes of runoff and sedimentation, soil moisture content, and properties under the effect of different water harvesting techniques (treatments). The study was conducted at three sites, representing environmental condition gradients, located in the southern part of the West Bank. For each treatment, the study evaluated soil chemical and physical properties, soil moisture at 30 cm depth, surface runoff and sedimentation at each site. Results showed that runoff is reduced by 65-85% and sedimentation by 58-69% in stone terraces and semi-circle bunds compared to the control at the semi-humid site. In addition, stone terraces and contour ridges significantly reduced the amount of total runoff by 80% and 73%, respectively, at the arid site. Soil moisture content was significantly increased by water harvesting techniques compared to the control in all treatments at the three study sites. In addition, the difference between the control and the water harvesting structures were higher in the arid and semi-arid areas than in the semi-humid area. Soil and water conservation, via utilization of water harvesting structures, is an effective principle for reducing the negative impact of high runoff intensity and subsequently increasing soil moisture storage from rainfall. Jessour systems in the valley and stone terraces were effective in increasing soil moisture storage, prolonging the growing season for natural vegetation, and decreasing the amount of supplemental irrigation required for growing fruit trees. PMID:19458998

Al-Seekh, Saleh H; Mohammad, Ayed G

2009-07-01

406

Kinetics of trace metal removal from tidal water by mangrove sediments under different redox conditions  

NASA Astrophysics Data System (ADS)

The extent in which redox conditions can affect the removal kinetics of 58Co and 65Zn from tidal water by mangrove sediments was evaluated in microcosm experiments, simulating a tidal flooding period of 6 h. The average half-removal time (t1/2) of 58Co from overlaying water was slightly higher (7.3 h) under an N2-purged water column than under an aerated water column (5.4 h). A lower difference was found for 65Zn (1.9 h vs. 1.5 h, respectively). Average removals of 58Co activities from water were 54.6% (N2 treatment) and 43.5% (aeration treatment), whereas these values were 88.0% and 92.7% for 65Zn, respectively. Very contrasting sorption kinetics of different radiotracers occurred, while more oxidising conditions favoured only a slightly higher removal. Average 58Co and 65Zn inventories within sediments were 30.4% and 18.8% higher in the aeration treatment, respectively. A stronger particle-reactive behaviour was found for 65Zn that was less redox-sensitive and more efficiently removed by sediments than 58Co.

Suzuki, K. N.; Machado, E. C.; Machado, W.; Bellido, A. V. B.; Bellido, L. F.; Osso, J. A.; Lopes, R. T.

2014-02-01

407

Bottom sediments and pore waters near a hydrothermal vent in Lake Baikal (Frolikha Bay)  

USGS Publications Warehouse

We discuss the redox environments and the compositions of bottom sediments and sedimentary pore waters in the region of a hydrothermal vent in Frolikha Bay, Lake Baikal. According to our results, the submarine vent and its companion nearby spring on land originate from a common source. The most convincing evidence for their relation comes from the proximity of stable oxygen and hydrogen isotope compositions in pore waters and in the spring water. The isotope composition indicates a meteoric origin of pore waters, but their major- and minor-element chemistry bears imprint of deep water which may seep through permeable faulted crust. Although pore waters near the submarine vent have a specific enrichment in major and minor constituents, hydrothermal discharge at the Baikal bottom causes a minor impact on the lake water chemistry, unlike the case of freshwater geothermal lakes in the East-African Rift and North America. ?? 2007.

Granina, L.Z.; Klerkx, J.; Callender, E.; Leermakers, M.; Golobokova, L.P.

2007-01-01

408

A possible case of caprine-associated malignant catarrhal fever in a domestic water buffalo (Bubalus bubalis) in Switzerland  

PubMed Central

Background Malignant catarrhal fever (MCF) is a fatal herpesvirus infection, affecting various wild and domestic ruminants all over the world. Water buffaloes were reported to be particularly susceptible for the ovine herpesvirus-2 (OvHV-2) causing the sheep-associated form of MCF (SA-MCF). This report describes the first case of possibly caprine-associated malignant catarrhal fever symptoms in a domestic water buffalo in Switzerland. Case presentation The buffalo cow presented with persistent fever, dyspnoea, nasal bleeding and haematuria. Despite symptomatic therapy, the buffalo died and was submitted to post mortem examination. Major findings were an abomasal ulceration, a mild haemorrhagic cystitis and multifocal haemorrhages on the epicardium and on serosal and mucosal surfaces. Eyes and oral cavity were not affected. Histopathology revealed a mild to moderate lymphohistiocytic vasculitis limited to the brain and the urinary bladder. Although these findings are typical for MCF, OvHV-2 DNA was not detected in peripheral blood lymphocytes or in paraffin-embedded brain, using an OvHV-2 specific real time PCR. With the aid of a panherpesvirus PCR, a caprine herpesvirus-2 (CpHV-2) sequence could be amplified from both samples. Conclusions To our knowledge, this is the first report of malignant catarrhal fever in the subfamily Bovinae, where the presence of CpHV-2 could be demonstrated. The etiological context has yet to be evaluated. PMID:22132808

2011-01-01

409

Impact of an external electron acceptor on phosphorus mobility between water and sediments.  

PubMed

The present work assessed the impact of an external electron acceptor on phosphorus fluxes between water and sediment interface. Microcosm experiments simulating a sediment microbial fuel cell (SMFC) were carried out and phosphorus was extracted by an optimized combination of three methods. Despite the low voltage recorded, ~96 mV (SMFC with carbon paper anode) and ~146 mV (SMFC with stainless steel scourer anode), corresponding to a power density of 1.15 and 0.13 mW/m(2), it was enough to produce an increase in the amounts of metal bound phosphorus (14% vs 11%), Ca-bound phosphorus (26% vs 23%), and refractory phosphorus (33% vs 28%). These results indicate an important role of electroactive bacteria in the phosphorus cycling and open a new perspective for preventing metal bound phosphorus dissolution from sediments. PMID:24210650

Martins, G; Peixoto, L; Teodorescu, S; Parpot, P; Nogueira, R; Brito, A G

2014-01-01

410

Retardation of volatile organic compounds in ground water in low organic carbon sediments  

SciTech Connect

It is postulated that adsorption onto aquifer matrix surfaces is only one of the processes that retard contaminants in ground water in unconsolidated sediments; others include hydrodynamic dispersion, abiotic/biotic degradation, matrix diffusion, partitioning to organic carbon, diffusion into and retention in dead-end pores, etc. This work aims at these processes in defining the K{sub d} of VOCs in sediments with low organic carbon content. Experiments performed include an initial column experiment for VOC (TCE and perchloroethylene(PCE)) retardation tests on geological materials, PCE and TCE data from LLNL sediments, and a preliminary multilayer sampler experiment. The VOC K{sub d}s in low organic carbon permeable aquifer materials are dependent on the VOC composition and independent of aquifer grain size, indicating that sorption was not operative and that the primary retarding factors are diffusion controlled. The program of future experiments is described.

Hoffman, F.

1995-04-01

411

Coupling effect of pH and dissolved oxygen in water column on nitrogen release at water-sediment interface of Erhai Lake, China  

NASA Astrophysics Data System (ADS)

Nitrogen (N), in the form of ammonia or nitrate, is a key limiting nutrient in many aquatic systems. Under certain environmental conditions it can be released from sediments into overlying water, which may have significant impact on water quality and result in continuous eutrophication. However, few studies have examined the long-term (nearly two months) coupling effect of environmental parameters on N dynamics at the sediment-water interface. This is particularly pertinent to improve the understanding of lake eutrophication processes. This study examines the coupling effects of pH and dissolved oxygen (DO) on N release at the sediment-water interface for the shallow Erhai Lake in China, and analyzes recent changes in environmental conditions and water quality to predict the risk of nitrogen release from sediment in the near future. Experimental results indicated that under anaerobic condition (DO?1 mg/L) and lower pH (pH = 6), ammonium was easily released into overlying water, potentially triggering algal blooms. Conversely aerobic conditions (DO = 8-10 mg/L) and higher pH (pH = 10) promoted nitrate release from sediment. The study also discusses possible mechanisms about the nitrogen dynamics at the sediment-water interface. Considering the overall effects of ammonium and nitrate on the trophic status of the water column, the recommended environmental condition in overlying water should be pH of around 8 under aerobic conditions. Based on the study findings, the nitrogen balance at the water-sediment interface was evaluated for different environmental conditions. Analysis of environmental conditions and water quality during 1992-2010 shows that present environmental conditions are not conducive to the release of nutrients from sediment, thereby protecting the water quality from serious endogenous pollution. However, the risk of nitrogen release from sediment sources might increase if environmental conditions change.

Zhang, Li; Wang, Shengrui; Wu, Zhihao

2014-08-01

412

A simple and effective method for preserving the sediment–water interface of sediment cores during transport  

Microsoft Academic Search

We describe a method for preserving the upper sediments of fragile sediment cores during transport from field sites and assess\\u000a potential effects on subsequent laboratory analyses. This method addresses the need to minimize disturbance to the surfaces\\u000a of unfrozen sediment cores used for paleoenvironmental or other high-resolution sedimentological analyses during transport.\\u000a A polymer gel (sodium polyacrylate) applied above the sediment

Jessica D. Tomkins; Dermot Antoniades; Scott F. Lamoureux; Warwick F. Vincent

2008-01-01

413

Water column and sediment nitrogen and phosphorus distribution patterns in the Florida Keys, USA  

NASA Astrophysics Data System (ADS)

Measurements of the distribution patterns of nutrients (ammonium, nitrate, orthophosphate, total N and total P) and chlorophyll concentrations were conducted under an interdisciplinary program known as SEAKEYS, initiated because of concern that anthropogenic nutrients may be impacting Florida coral reefs. Samples were collected along transects that extended from passes or canals to 0.5 km offshore of the outermost reefs. Seven of the transects were either in the Biscayne National Park (BNP) and Key Largo (upper keys) or Seven Mile Bridge/Looe Key (upper part of lower keys) areas, which have the best present-day reef development; the two in the middle keys off Long Key were in an area of minimal reef development where passes allow estuarine Florida Bay water to flow onto the Florida reef platform. Off the upper keys, water column concentrations of N and chl a were elevated near marinas and canals (1 ?M NO3, 1 ?g/l chl a), but returned to oligotrophic levels (e.g., chl a ? 0.25 ?g/l; NO3 ? 0.25 ?M; NH4 ? 0.10 ?M) within 0.5 km of shore. Phosphorus concentrations, however, were often higher offshore ? 0.2 ?M PO4). Sediment interstitial nutrient concentrations decreased from inshore to the offshore reef areas (e.g., ? 100 ?M NH4 inshore to ? 50 ?M NH4 offshore) and were comparable to those of some presumably pristine coastal and reef carbonate sediments. Sediment bulk N was higher nearshore and decreased steeply offshore ( ? 60 ?g-at N/gm sediment to ? 20 ?g-at N/gm sediment, respectively); bulk P concentrations (? 6 ?g- at P/gm sediment) varied little or exhibited the reverse pattern. Sediment N:P ratios were consistently lower offshore (1 10 vs. 20 40 nearshore). Higher offshore P concentrations are attributed to periodic upwelling along the shelf edge. In the middle keys water column nutrients and chl a concentrations were both higher than those in the upper keys, and there was less of an inshore-offshore decrease than that noted in the upper keys. Sediment nutrients were higher also, and nearshore and offshore areas did not differ. Water column and sediment nutrient concentrations and distribution patterns in the upper part of the lower keys were most similar to those measured in the upper keys. Overall, the present data do not support the contention that reef areas in the upper keys are accumulating elevated loads of land-derived nutrients via surface water flow, but does document moderately elevated nutrient and chl a levels in many developed nearshore areas. Most of