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Fresh Water Studies

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Full-Text Articles in Environmental Monitoring

Effects Of Wastewater Discharges On Periphyton Growth In Lake Mead, Nevada-Arizona, Marsha Korb Morris Dec 1982

Effects Of Wastewater Discharges On Periphyton Growth In Lake Mead, Nevada-Arizona, Marsha Korb Morris

Publications (WR)

A study of the effects of secondary-treated wastewater on periphyton growth in Lake Mead, Nevada-Arizona was conducted from September 1979 to December 1980. Periphyton ash-free dry weight, chlorophyll-a, dominant species composition, and alkaline phosphatase activity were measured on fiberglass substrates. Substrates were incubated for two to four weeks in littoral and limnetic habitats. Physical and chemical variables and phytoplankton chlorophyll-a were measured concurrently.

Transparency increased with increasing distance from the discharge. Secchi depth ranged from 0.75 m at the discharge confluence (station 2) in August, to greater than 20 m at the most distant stations (stations 9 and 10) in …


An Ecological Analysis Of Relic Diatoms In Sediments Of Las Vegas Bay, Lake Mead, David Ross Hetzel Jul 1982

An Ecological Analysis Of Relic Diatoms In Sediments Of Las Vegas Bay, Lake Mead, David Ross Hetzel

Publications (WR)

Relic diatoms in sediments of the inner Las Vegas Bay, near the Las Vegas Wash sewage inflow, were examined in order to assess historic trophic conditions in this area of Lake Mead. Diatom sedimentation rates and ratios of Araphidineae/Centrales (A/C) diatom groups were determined from sediment cores collected in the old wash channel 1.5 km from the sewage inflow (station 2), in a small cove 1.5 km further downstream (station 3) and in an adjacent embayment off Gypsum Wash (station 4). Diatom sedimentation rates generally increased from the bottom to the top of each core, but pronounced minima existed at …


Development, Verification And Use Of Methods To Model Chemical And Thermal Processes For Lakes Mead And Powell, John Eric Edinger, Edward M. Buchak, Joseph S. Norton, Bureau Of Reclamation Jun 1982

Development, Verification And Use Of Methods To Model Chemical And Thermal Processes For Lakes Mead And Powell, John Eric Edinger, Edward M. Buchak, Joseph S. Norton, Bureau Of Reclamation

Publications (WR)

Analysis and development of carbonate-bicarbonate chemical subroutine.


Report No 56 - 1981 Review Of Rainfall And Wetlands In The South-West Of Western Australia, J. A.K. Lane, D. R. Munro Jan 1982

Report No 56 - 1981 Review Of Rainfall And Wetlands In The South-West Of Western Australia, J. A.K. Lane, D. R. Munro

Fisheries Research Reports

An account is given of the biological principles involved in decisions concerning duck-shooting seasons in the south-west of Western Australia.

The conditions for waterfowl which prevailed during 1981 are described through the use of rainfall statistics and data obtained from the Department's wetland monitoring programme.

Rainfall was generally average over central and northern areas of the south-west during 1981. Rainfall in southern areas, however, was generally

below to much-below-average, although south coastal areas from Augusta to Albany received average falls.

Unusually heavy falls were recorded in North Coastal, North Central and Central Coastal Districts in May, and average falls were …


Diagenesis Of Organic Matter In Las Vegas Bay And Bonelli Bay, Lake Mead, James W. Murray, Carolyn J. Jones, Kathy Kuivila, Jeff Sawlan Jul 1981

Diagenesis Of Organic Matter In Las Vegas Bay And Bonelli Bay, Lake Mead, James W. Murray, Carolyn J. Jones, Kathy Kuivila, Jeff Sawlan

Publications (WR)

The interstitial water chemistry of the sediments of Las Vegas Bay and Bonelli Bay in Lake Mead has been studied as part of a comprehensive water quality study of those locations. Pore water and solid phase analyses were completed from four stations in Las Vegas Bay and two stations in Bonelli Bay. At both locations the pore water compositions and organic matter diagenesis in the sediments are dominated by sulfate reduction. This major role of sulfate reduction is unusual for lake sediments and reflects the fact that SO4 is the major anion in the lake water. In addition, gypsum …


Chemical And Biological Structure Of Lake Mead Sediments, Richard T. Prentki, Larry J. Paulson, John R. Baker Jun 1981

Chemical And Biological Structure Of Lake Mead Sediments, Richard T. Prentki, Larry J. Paulson, John R. Baker

Publications (WR)

Lake Mead has undergone a serious decline since Glen Canyon Dam was constructed 450 km upstream in 1963.

State fisheries management agencies are concerned that the decline was caused by water level fluctuations and more severe drawdowns during the bass spawning season, when the operation of Hoover Dam was altered during the post-Lake Powell period.

The construction of Glen Canyon Dam and formation of Lake Powell in 1963 drastically altered the natural discharge and temperature cycles and decreased suspended sediment and nutrient loading in the Colorado River inflow to Lake Mead. Recent studies indicate that these changes in nutrient loading …


Maine's Whitewater Rapids And Their Relevance To The Critical Areas Program, Janet Mcmahon Apr 1981

Maine's Whitewater Rapids And Their Relevance To The Critical Areas Program, Janet Mcmahon

Maine Collection

Maine's Whitewater Rapids and Their Relevance to the Critical Areas Program

by Janet McMahon

Planning Report No. 74, Critical Areas Program, 184 State St., Augusta, Maine,

April, 1981 (additions made in October, 1981). Reprinted July, 1983.

Contents: Introduction / Natural History of Whitewater Rapids / Methods / Criteria / Results / Conclusions / General Evaluation of Whitewater Rapids for Inclusion on the Register of Critical Areas / Bibliography / Action Plan


Report No 47 - 1980 Review Of Rainfall And Wetlands In The South-West Of Western Australia, J. A.K. Lane, D. R. Munro Jan 1981

Report No 47 - 1980 Review Of Rainfall And Wetlands In The South-West Of Western Australia, J. A.K. Lane, D. R. Munro

Fisheries Research Reports

An account is given of the biological principles involved in decisions concerning duck-shooting seasons in the south-west of Western Australia.

The conditions for waterfowl which prevailed during 1980 are described through the use of rainfall statistics and data obtained from the Department's wetland monitoring programme.

1980 was the fifth consecutive year of below-average rainfall in all five Meteorological Districts of the south-west. 1976 to 1980 was thus' the south-west's driest five-year period since 1913 at least.

Low rainfall during 1980 resulted in a further decline in the condition of wetlands throughout most of the inland south-west, Few gauged wetlands increased …


Bulletin 3929 - Irrigation In Western Australia, K S. Cole Dec 1980

Bulletin 3929 - Irrigation In Western Australia, K S. Cole

Bulletins - 3000 - 3999

Irrigation is essential in many parts of the world to produce essential food and profitable cash crops. Generally, those areas of land with less than 360 mm of rain spread over a distinct wet season of several months cannot grow crops for food or cash on rainfall alone. Then irrigation becomes necessary unless some peculiarity such as an oasis exists.


Methods For Biological, Chemical, And Physical Analyses In Reservoirs, Penelope E. Kellar, Sherell A. Paulson, Larry J. Paulson Dec 1980

Methods For Biological, Chemical, And Physical Analyses In Reservoirs, Penelope E. Kellar, Sherell A. Paulson, Larry J. Paulson

Publications (WR)

This manual contains detailed descriptions of biological, chemical and physical sampling and analytical procedures used at the Lake Mead Limnological Research Center. The manual was prepared in response to requests made by numerous individuals involved in the Las Vegas Valley Water Quality Program. This manual represents what we consider to be a reasonably complete compilation of methods useful in studying both general and specific limnological questions. While each section is sufficiently detailed to be of use to investigators with little experience in limnological methodology, the methods can be used on a wide variety of lakes and reservoirs, with relatively little …


Effects Of Changes In Surface Water Regime And/Or Land Use On The Vertical Distribution Of Water Available For Wetland Vegetation: Dynamic Model Of The Zone Of Aeration (Appendix To Part 1 Of Completion Report For Project A-023-Ark), Robert N. Maccallum, R. A. Sims Jun 1980

Effects Of Changes In Surface Water Regime And/Or Land Use On The Vertical Distribution Of Water Available For Wetland Vegetation: Dynamic Model Of The Zone Of Aeration (Appendix To Part 1 Of Completion Report For Project A-023-Ark), Robert N. Maccallum, R. A. Sims

Arkansas Water Resources Center Technical Reports

Appendix to Part 1 of Completion Report for Project A-023-ARK


Effects Of Changes In Surface Water Regime And/Or Land Use On The Vertical Distribution Of Water Available For Wetland Vegetation: Portable Environmental Data Logger And Sensors (Part Ii Of Completion Report For Project A-023-Ark), Robert N. Maccallum, R. A. Sims Jun 1980

Effects Of Changes In Surface Water Regime And/Or Land Use On The Vertical Distribution Of Water Available For Wetland Vegetation: Portable Environmental Data Logger And Sensors (Part Ii Of Completion Report For Project A-023-Ark), Robert N. Maccallum, R. A. Sims

Arkansas Water Resources Center Technical Reports

An instrumentation and recording package and several transducers were constructed and used to collect data on the environmental parameters thought to affect wetland vegetation growth and reproduction. These parameters were temperature, humidity, wind velocity, depth of water table, and amount of surface water. The data were collected four times a day and recorded on a magnetic cassette tape that could record for as long as 90 days. The tapes were read and the data were converted to engineering units by a microcomputer-based instrument constructed for that purpose.


Effects Of Changes In Surface Water Regime And/Or Land Use On The Vertical Distribution Of Water Available For Wetland Vegetation: Dynamic Model Of The Zone Of Aeration (Part 1 Of Completion Report For Project A-023-Ark), Robert N. Maccallum, R. A. Sims Jun 1980

Effects Of Changes In Surface Water Regime And/Or Land Use On The Vertical Distribution Of Water Available For Wetland Vegetation: Dynamic Model Of The Zone Of Aeration (Part 1 Of Completion Report For Project A-023-Ark), Robert N. Maccallum, R. A. Sims

Arkansas Water Resources Center Technical Reports

A mathematical model by Green, simulating one-dimensional vertical ground-water movement in unsaturated soils of the prairie region of Kansas, has been adapted for use in a wetlands environment typified by the wetlands forest of Eastern Arkansas. The model consists of two second-order, non-linear, partial differential equations and an algorithm for their numerical solution. The original model was extended to include functions for seasonal changes in transpiration and for drainage of excess precipitation. Before the addition of the two functions, the model reliability was limited to one growth season.


Influence Of Las Vegas Wash Density Current On Nutrient Availability And Phytoplankton Growth In Lake Mead, John R. Baker, Larry J. Paulson Jun 1980

Influence Of Las Vegas Wash Density Current On Nutrient Availability And Phytoplankton Growth In Lake Mead, John R. Baker, Larry J. Paulson

Publications (WR)

Density currents are commonly formed in reservoirs because of temperature or salinity induced density differences between inflowing and receiving waters. Anderson and Pritchard (1951) were among the first to demonstrate this in their investigations of density currents in Lake Mead. They found that the Colorado River formed an underflow in Lake Mead during the winter, an overflow in the spring and an interflow in the summer and fall. Wunderlich and Elder (1973) have since described the hydromechanics of these types of flow patterns, and density currents have been reported for several other large reservoirs (Carmack et al. 1979, Johnson and …


Nutrient Interactions Among Reservoirs On The Colorado River, Larry J. Paulson, John R. Baker Jun 1980

Nutrient Interactions Among Reservoirs On The Colorado River, Larry J. Paulson, John R. Baker

Publications (WR)

Interactions among physical, chemical and biological processes in reservoirs can significantly alter the characteristics of the discharge (Neel 1963, Wright 1967, Hannan 1979) that, in turn, can influence the ecology of the river downstream .(Ward and Stanford 1979). Investigations of the Colorado River, system reveal that reservoir-induced changes in the river can also affect downstream reservoirs. The formation of Lake Powell, in 1963 was accompanied by reductions in suspended sediment and nutrient loading and changes in the seasonal temperature and discharge cycles of the Colorado River. In this paper, we evaluate how these changes have influenced the nutrient and trophic …


Macrobenthic Communities Of An Industrialized Seaport Ecosystem: The Southern Branch Of The Elizabeth River, Virginia, Steven D. Hawthorne Apr 1980

Macrobenthic Communities Of An Industrialized Seaport Ecosystem: The Southern Branch Of The Elizabeth River, Virginia, Steven D. Hawthorne

Biological Sciences Theses & Dissertations

Macrobenthic invertebrates of an industrialized seaport ecosystem were studied seasonally from October, 1977 through July, 1978. Five stations were selected along the Southern Branch of the Elizabeth River, Virginia. The stations ranged from an area of heavy industrialization to a non-urbanized environment. At each station, bottom water was measured for salinity, temperature, dissolved oxygen, and pH. Within each sampling area, macrobenthic infauna! invertebrates were collected from in and out of channel sites along with sediment samples for various types of physicochemical analysis.

Community structure was spatially homogeneous at station sites and throughout the stations along the River. Slightly acidic pH …


Chemistry Of The Spring Waters Of The Ouachita Mountains Excluding Hot Springs, Arkansas, George H. Wagner, Kenneth F. Steele Mar 1980

Chemistry Of The Spring Waters Of The Ouachita Mountains Excluding Hot Springs, Arkansas, George H. Wagner, Kenneth F. Steele

Arkansas Water Resources Center Technical Reports

This report is based on the chemical analysis of the waters from 93 springs and 9 wells. Springs, when free from metal plumbing, provide an uncontaminated source of the ground water and it was desired to obtain water uncontaminated with metals. A few wells were added to the list, usually because of their unique location in the sampling grid.


Evaluation Of Possible Temperature Fluctuations From Proposed Power Modifications At Hoover Dam, Larry J. Paulson, John R. Baker, U.S. Water And Power Resources Service Mar 1980

Evaluation Of Possible Temperature Fluctuations From Proposed Power Modifications At Hoover Dam, Larry J. Paulson, John R. Baker, U.S. Water And Power Resources Service

Publications (WR)

There are several planned alternatives for increasing the generation capacity of Hoover Dam to help meet peak power demands. These alternatives include: (a) uprating the existing generating units, (b) replacing or adding one or more generating units and (c) adding reversible pumped-storage hydroelectric units. Since the existing generators are at the end of their economic life and have to be replaced, their uprating has been scheduled as routine maintenance. This will increase the generating capacity of the Hoover Dam powerplant from 1240 MW to 1810 MW, but the anticipated capacity for meeting power demand is 2300 MW. Therefore, modifications (alternatives …


Evaluation Of Impacts Associated With Reregulation Of Water Levels In Lake Mohave, Larry J. Paulson, John R. Baker, U.S. Water And Power Resources Service Mar 1980

Evaluation Of Impacts Associated With Reregulation Of Water Levels In Lake Mohave, Larry J. Paulson, John R. Baker, U.S. Water And Power Resources Service

Publications (WR)

The U.S. Water and Power Resources Service is considering reregulating Lake Mohave water levels to increase the net power benefit from Hoover Dam. Reregulation will not increase the generation capacity of the Hoover powerplant but it will enable the plant operation to be increased when the energy has greater monetary value. Energy generated at different times of the year has different market value, the highest being in January-March and July- September. By generating more power during these periods more net monetary benefit can be derived from Hoover Dam. The total volume of water released from Hoover Dam over an annual …


The Limnological Status Of Lake Mead And Lake Mohave Under Present And Future Powerplant Operations Of Hoover Dam, Larry J. Paulson, John R. Baker, James E. Deacon, U.S. Water And Power Resources Service Jan 1980

The Limnological Status Of Lake Mead And Lake Mohave Under Present And Future Powerplant Operations Of Hoover Dam, Larry J. Paulson, John R. Baker, James E. Deacon, U.S. Water And Power Resources Service

Publications (WR)

The ever-increasing demand for energy in the southwest has led to a search for additional sources of power generation. Coal-fired powerplants currently provide most of the baseline energy in the southwest, but this must be supplemented with hydroelectric power during periods of peak demand. In order to provide additional peaking power, the U.S. Bureau of Reclamation is considering a number of projects to modify existing hydroelectric facilities, or add new facilities in the Lake Mead Recreation Area. The Hoover Powerplant Modification Feasibility Investigation was authorized by Congress on December 16, 1975 to determine the feasibility of: (i) adding one or …


Influence Of Dredging And High Discharge On The Ecology Of Black Canyon, Larry J. Paulson, Theron G. Miller, John R. Baker, U.S. Water And Power Resources Service Jan 1980

Influence Of Dredging And High Discharge On The Ecology Of Black Canyon, Larry J. Paulson, Theron G. Miller, John R. Baker, U.S. Water And Power Resources Service

Publications (WR)

The Water and Power Resources Service is considering dredging in Black Canyon to create a larger forebay to accommodate higher peak discharges and reverse flows for proposed modifications to Hoover Dam. The Black Canyon area from Hoover Dam to Willow Beach supports a heavily utilized trout fishery and is important habitat for the razorback sucker (Xyrauchen texanus) and possibly bonytail chub (Gila elegans). The Water and Power Resources Service initiated this investigation to determine what effect dredging and higher peak-discharges would have on the ecology of Black Canyon.


Lake Mead And Lake Powell Salinity Reports, Cathy Lee, Steve Gazafy Feb 1979

Lake Mead And Lake Powell Salinity Reports, Cathy Lee, Steve Gazafy

Publications (WR)

The enclosed reports were compiled for the Colorado River Water Quality Office based on salinity data for Lake Mead and Lake Powell. According to the regional director of the office, the reports are not considered "polished" documents for public distribution. However, he considers them to be "interesting, rough appraisals of general trends that may be very important In our understanding the hydro-salinity system in the Colorado River."


Potential Use Of Hydroelectric Facilities For Manipulating The Fertility Of Lake Mead, Larry J. Paulson, John R. Baker, James E. Deacon Jan 1979

Potential Use Of Hydroelectric Facilities For Manipulating The Fertility Of Lake Mead, Larry J. Paulson, John R. Baker, James E. Deacon

Publications (WR)

Analysis of historical nutrient data for Lake Mead indicates that the fertility of the reservoir has decreased which may be the cause for a corresponding decline in the largemouth bass population. However, it appears that fertility can be manipulated by altering the operation of the dam. The depletion of nutrients in the euphotic zone by phytoplankton and subsequent accumulation in the hypolimnion during summer and fall provide a natural nutrient gradient from which water of varying fertility can be drawn for discharge. This combined with alterations in the depth or seasonal pattern of discharge can possibly be used to enhance …


Water Resources Aspects Of Coal Transportation By Slurry Pipeline, James W. Moore Dec 1977

Water Resources Aspects Of Coal Transportation By Slurry Pipeline, James W. Moore

Arkansas Water Resources Center Technical Reports

No abstract provided.


Final Report: Lake Mead Monitoring Program, James E. Deacon Sep 1977

Final Report: Lake Mead Monitoring Program, James E. Deacon

Publications (WR)

The Lake Mead Monitoring Program has continued to develop information on the limnological condition of Lake Mead. We have significantly increased our analytical capabilities this year by developing a cooperative project with the U.S. Bureau of Reclamation and continuing our cooperative program with E.P.A. We also were able to derive significant benefit from the reviews of the Pollution Abatement Project written by Clair Sawyer and Charles Goldman. Partially as a result of these reviews we have had the opportunity to interpret and more fully explain the significance of our work to a wider public audience than would otherwise have been …


Limnological Aspects Of Lake Mead, Nevada-Arizona, John R. Baker, James E. Deacon, Thomas A. Burke, Samuel S. Egdorf, Larry J. Paulson, Richard W. Tew, Bureau Of Reclamation Jun 1977

Limnological Aspects Of Lake Mead, Nevada-Arizona, John R. Baker, James E. Deacon, Thomas A. Burke, Samuel S. Egdorf, Larry J. Paulson, Richard W. Tew, Bureau Of Reclamation

Publications (WR)

Lake Mead is a deep, subtropical, moderately productive, desert impoundment with a negative heterograde oxygen profile occurring during; the summer stratification. investigations of the Boulder Basin of Lake Mead by the University of Nevada were initiated in November 1971. The primary objective of the study was to determine what effects industrial and sewage effluent from the Las Vegas metropolitan area, discharged into Las Vegas Bay, have had on the water quality and limnological conditions of Boulder Basin. Data from the 1975-76 period are presented in detail, with earlier data included in the summaries and discussions. Measurements of water temperature, dissolved …


The Limnetic Zooplankton Community Of Boulder Basin, Lake Mead In Relation To The Metalimnetic Oxygen Minimum, Thomas A. Burke Apr 1977

The Limnetic Zooplankton Community Of Boulder Basin, Lake Mead In Relation To The Metalimnetic Oxygen Minimum, Thomas A. Burke

Publications (WR)

The limnetic zooplankton community of Boulder Basin, Lake Mead, was examined to determine the role of this community in the development of a metalimnetic oxygen minimum which regularly occurs in the lake. Analysis of the community from May 1975 to April 1976 revealed that zooplankton maintain high populations within the metalimnion during summer stratification. The species composition of the community changes noticeably during the summer, but due to advanced stages excysting from resting forms, a complete assemblage of individuals are found throughout the 74 day period studied. Thermal stratification was weak, covering a 30 meter metalimnion. Eddy currents powered by …


Fisheries Report No 27 - A Survey Of Recreational Usage Of South Coastal Estuaries Of Western Australia, N. Caputi, R C.J. Lenanton Jan 1977

Fisheries Report No 27 - A Survey Of Recreational Usage Of South Coastal Estuaries Of Western Australia, N. Caputi, R C.J. Lenanton

Fisheries Research Reports

Over recent years, factors such as the State's population increase, a generally higher standard of living which enables people to have more leisure time, and better roads, particularly from the Eastern States of Australia, have all contributed towards an increase in the general recreational usage of the Western Australian south coast estuaries.

To aid proper planning of facilities to cater for an increasing number of visitors in these south coast estuaries, management agencies must be able to quantify the recreational usage in this group of estuaries.

This survey, therefore, attempts to identify and quantify the different recreational pursuits of visitors …


Effect Of Deforestation By The Douglas-Fir Tussock Moth On The Quality Of Streamflow And Stream Productivity Parameters, Martin Ed Hicks Jan 1977

Effect Of Deforestation By The Douglas-Fir Tussock Moth On The Quality Of Streamflow And Stream Productivity Parameters, Martin Ed Hicks

All Master's Theses

The purpose of this study was to determine if deforestation by a recent outbreak of Douglas-fir tussock moth and logging of such deforested timber has had any effect on stream water quality. To determine this, seven different watersheds of three types were examined. The three types were: undamaged watersheds as controls, watersheds with deforestation and watersheds with deforestation where the timber was subsequently logged. Twenty-four variables were used to determine water quality. Included were seven biological and seventeen chemical variables.

In general, the results indicate only seasonal fluctuations and differences between watersheds due to inherent properties of individual watersheds. Increased …


A Review Of The Limnology Of And Water Quality Standards For Lake Mead, Charles R. Goldman Oct 1976

A Review Of The Limnology Of And Water Quality Standards For Lake Mead, Charles R. Goldman

Publications (WR)

1. The waters of Las Vegas Bay, a heavily utilized recreational resource, receive discharges from a variety of municipal and industrial waste sources. The U.S. Environmental Protection Agency has determined, on the basis of numerous studies, that the present water quality violates state and federal standards and constitutes a public nuisance. Consultants have advised the Sewage and Wastewater Advisory Committee that rapid abatement of the alleged pollution conditions can be achieved by an advanced wastewater treatment (AWT) plant.

2. The major problems in Las Vegas Bay are an objectionable water color, excessive turbidity, noxious odors, and oxygen depletion in certain …