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Articles 421 - 450 of 454

Full-Text Articles in Environmental Indicators and Impact Assessment

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 …


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 …


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 …


A Guide To The Threatened And Endangered Vascular Plants Of The Lake Mead National Recreation Area, James S. Holland, Wesley E. Niles, Charles L. Douglas, Dennis R. Schramm Jan 1980

A Guide To The Threatened And Endangered Vascular Plants Of The Lake Mead National Recreation Area, James S. Holland, Wesley E. Niles, Charles L. Douglas, Dennis R. Schramm

Publications (WR)

This illustrated guide was prepared to provide the botanical community, land managers, and other interested persons with a reference that describes and locates the twelve plant taxa currently being considered by the Fish and Wildlife Service for threatened or endangered status in or around the Lake Mead National Recreation Area. The guide is intended to assist managers of government agencies in determining the presence of these species and in defining management programs for their protection. The guide should be consulted prior to any construction project. If a potential conflict is identified, an onsite evaluation should be conducted early in the …


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.


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 …


A Stream Survey Of Riley Creek, Coles County, Illinois, Using Macroinvertebrates As Indicators Of Organic Pollution, Joseph R. Rowe Jan 1977

A Stream Survey Of Riley Creek, Coles County, Illinois, Using Macroinvertebrates As Indicators Of Organic Pollution, Joseph R. Rowe

Masters Theses

A stream survey of Riley Creek in Coles County Illinois, was undertaken to determine ecological trends and the qualitative status of the aquatic community throughout the course of the stream.

The survey encompassed the entire length of Riley Creek from the area of its status as an intermittant waterway to its confluence with Cassel Creek. Sampling periods included the months of April, May, June, July, October and November.

Macroinvertebrate collections were made at six locations along the stream approximately equidistant from each other. The organisms were assigned tolerance levels as designated by the Illinois Environmental Protection Agency.

Physical and chemical …


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 …


Report On Wastewater Disposal To Board Of County Commissioners, Clark County Nevada, Clair N. Sawyer Oct 1976

Report On Wastewater Disposal To Board Of County Commissioners, Clark County Nevada, Clair N. Sawyer

Publications (WR)

This report is concerned with the management of waste-waters and subsurface drainage from the City of Las Vegas and its environs and the BMI complex, all in Clark County, Nevada. The prime objective is to recommend a plan of action which will utilize the natural resources of the area in the least costly manner and still protect Lake Mead for recreational purposes and use as a public water supply, At this writing, conditions in the upper Las Vegas arm of Boulder Basin are quite unsatisfactory for some recreational purposes due to the extensive blooms of algae which develop. Experience at …


Distribution Of Stream Pollution In Lake Water, Richard W. Tew, Samuel S. Egdorf, James E. Deacon May 1976

Distribution Of Stream Pollution In Lake Water, Richard W. Tew, Samuel S. Egdorf, James E. Deacon

Publications (WR)

Wastewater effluent-laden waters from Las Vegas Wash (LVW) form a density current that may be detected in Boulder Basin of Lake Mead at considerable distances from the wash estuary. This led to the suspicion that water from the inflowing stream [40 mgd (1.5 X 105 cu m/day)] might not be rapidly diluted in the enormous volume of the lake [19 mil acre-ft (2.3 X 1010 cu m)], but might persist as a recognizable entity to the vicinity of the intake of a major water source for populous Clark County, Nev.

Because of the detection sensitivity implicit in the …


The Nature And Distribution Of Enteric Bacteria In Las Vegas Bay, Samuel S. Egdorf Apr 1976

The Nature And Distribution Of Enteric Bacteria In Las Vegas Bay, Samuel S. Egdorf

Publications (WR)

The distribution of water and of enteric bacteria of possible fecal origin into Las Vegas Bay from Las Vegas Wash was determined. Determination of distribution patterns was attained by applying the concept of the population component ratio of enteric bacteria. The development and application of new techniques and methods implicit in the application of the "component ratio" concept are discussed. The unreliability of thoroughly referenced techniques and methods generally accepted as standard are treated in detail. Physical factors affecting the distribution and deposition of enteric bacteria (including those of special public health importance) in Las Vegas Bay are also discussed.


Seasonal And Spatial Variation In Primary Productivity In Boulder Basin, Lake Mead, Clark County, Nevada, Isamu Aoki May 1975

Seasonal And Spatial Variation In Primary Productivity In Boulder Basin, Lake Mead, Clark County, Nevada, Isamu Aoki

Publications (WR)

The 14C light and dark bottle technique for measurement of primary production was utilized as a means of assessing the amount of inorganic carbon being converted Into organic form by the photosynthesis of phytoplankton populations In the Boulder Basin of Lake Mead.

Spatial and time series changes of productivity levels observed at eight sampling locations within Boulder Basin Indicate that the Influence of treated municipal arts' industrial effluent flowing into Les Vegas Bay is contributing high levels of available nutrients at Las Vegas Wash Inlet to cause productivity to approximate those levels associated with polluted waters.

Productivity levels at …


The Use Of Color Infrared Aerial Photography In Determining Salt Marsh Vegetation And Delimiting Man-Made Structures Of Lynnhaven Bay, Virginia, Robert E. Holman Lll Apr 1974

The Use Of Color Infrared Aerial Photography In Determining Salt Marsh Vegetation And Delimiting Man-Made Structures Of Lynnhaven Bay, Virginia, Robert E. Holman Lll

Biological Sciences Theses & Dissertations

Color infrared aerial photography was found to be superior to color aerial photography in an ecological study of Lynnhaven Bay, Virginia. The research was divided into three phases: 1) determination of the feasibility of correlating color infrared aerial photography with wetland species composition and zonation patterns, 2) determination of the accuracy of the aerial interpretation and problems related to the aerial method used, and 3) comparison of developed with undeveloped areas along Lynnhaven Bay's shoreline.

Wetland species composition and zonation patterns of major cones were correlated with aerial infrared photography and resulted in a high degree of accuracy. Problems with …


Studies On The Causes Of Tree Distribution In A Forest Type In The Dismal Swamp National Wildlife Refuge, Thomas A. Janszen Apr 1974

Studies On The Causes Of Tree Distribution In A Forest Type In The Dismal Swamp National Wildlife Refuge, Thomas A. Janszen

Biological Sciences Theses & Dissertations

Vegetational composition and environmental parameters were analyzed in a forest type of the Dismal Swamp. A 0.5 ha forest stand was divided into 200 5 x 5 meter contiguous quadrats and the tree size classes were precisely mapped. Fifty soil samples were analyzed for texture, pH, and major nutrients. A topographic map was constructed with precision to 0.01 ft. Analysis of variance tests showed non-randomness to exist in soil texture and nutrient content while homogeneity tests showed non-randomness in distribution of some woody species. Factor analysis indicated no significant correlations between soil quality, topography, and woody species. Findings indicate that …


An Ecological Study Of The Craney Island Disposal Area In Hampton Roads, Virginia, David Wallace Laist Apr 1974

An Ecological Study Of The Craney Island Disposal Area In Hampton Roads, Virginia, David Wallace Laist

Biological Sciences Theses & Dissertations

A one year ecological study was conducted on the Craney Island Disposal Area in Hampton Roads, Virginia. This study attempted to identify the flora and fauna inhabiting the spoil deposits and trace the development of communities from the time of deposition through the initial stages of succession.

One hundred and ninety-two species were identified including 48 vascular plants, 66 insects, 48 birds, 18 species of algae, 4 crustaceans, and 8 vertebrates. The study area was divided into six zones based on substrate characteristics and species composition. The successional patterns and biotic interactions within each zone were discussed.


Seasonal Changes In Water Quality And Primary Productivity In Doe Valley Lake, Edmond J. Bacon, Stuart E. Neff Mar 1974

Seasonal Changes In Water Quality And Primary Productivity In Doe Valley Lake, Edmond J. Bacon, Stuart E. Neff

KWRRI Research Reports

Primary productivity and water quality were studied in Doe Valley Lake, a 147-hectare impoundment on Doe Run, a spring-fed stream in Meade County, Kentucky, from 13 June 1969 to 31 July 1972. Doe Valley Lake is monomictic during most winter seasons, but it is dimictic during more severe winters because of its morphometry and location on the borderline climatic region for dimictic lakes (37° N latitude). Oxygen depletion in the hypolimnion is severe, and anaerobic conditions usually prevail by late June. A hypolimnetic areal deficit of 0.038 mg/cm2/day was calculated. Supersaturation of oxygen in the epilimnion was common, …


Rate Of Growth As A Method Of Assessing Water Quality, George L. Johnston Jan 1974

Rate Of Growth As A Method Of Assessing Water Quality, George L. Johnston

Masters Theses

A study of the Embarras River basin was conducted to determine if rate of growth could be used as an indicator of water quality. Six species of sucker were collected from five locations using hand seines and electrofishing gear from December 1970 to December 1971. Tests of eighteen water quality parameters were conducted from November 1970 to November 1971.

The fish were measured and scale samples taken. The rate of growth of the fish taken at the five stations was analyzed and compared using the single classification analysis of variance. Condition factors were also compared.

Although there was some difference …


Phytoplankton Distribution And Water Quality Indices For Lake Mead (Colorado River), Robert D. Staker, Robert W. Hoshaw, Lorne G. Everett Jan 1974

Phytoplankton Distribution And Water Quality Indices For Lake Mead (Colorado River), Robert D. Staker, Robert W. Hoshaw, Lorne G. Everett

Publications (WR)

Phytoplankton samples were collected in Lake Mend 6 times from September 1910 to June 1971 for 8 stations at depths of 0. 3, 5, 10, 20, and 30 m. These samples were processed through a Millipore filter apparatus and 79 planktonic algae were identified. Algal divisions represented were Bacillariophyta, 42 species; Chlorophyta, 18 ; Cyanophyta, 9; Chrysophyta, 3; Cryptophyta, 3; Pyrrophyta, 2; and Euglenophyta, 2. Blue-green algae were dominant in late summer and fall; green algae, diatoms, and, cryptomonads in winter; and green algae in spring. The early summer flora was best represented by the Chlorophyta, Cryptophyta, and Chrysophyta. Palmer's …


Inventory Of Lake Studies In Maine, Charles F. Wallace Jr., James M. Strunk Jul 1973

Inventory Of Lake Studies In Maine, Charles F. Wallace Jr., James M. Strunk

Maine Collection

Inventory of Lake Studies in Maine

By Charles F. Wallace, Jr. and James M. Strunk

State Planning Office, Water Resources Planning Division, July 1973.

"Printed under Appropriation Number 4248.5 and financially assisted by planning grants from the United States Water Resources Council Title III funds."

Contents: Introduction / Investigating Agencies / Federal Agencies / State Agencies / Regional Planning Commissions and Economic Development Districts / Maine Colleges and Universities / Private / Other Private / Other / Appendices


Phytoplankton Successions And Lake Dynamics In Las Vegas Bay, Lake Mead, Nevada, Ervon R. Koening, Richard W. Tew, James E. Deacon Oct 1972

Phytoplankton Successions And Lake Dynamics In Las Vegas Bay, Lake Mead, Nevada, Ervon R. Koening, Richard W. Tew, James E. Deacon

Publications (WR)

Phytoplankton successions, applications of the general growth equation, and physical measurements have been employed to investigate events occurring at the interface between industrial and sewage effluent contained in Las Vegas Wash and the waters of Lake Mead, Nevada. The data indicate that the entering waters tend to form a density current interrupted at intervals by dynamic effects generated in the lake. The dynamic relationships described here for the spring months suggest that a much more thorough understanding of physical, chemical and biological interactions is necessary to permit solution of the numerous problems of Las Vegas Bay discussed or alluded to …


A Mathmatical Model Of Primary Productivity And Limnological Patterns In Lake Mead, Lorne G. Everett Sep 1972

A Mathmatical Model Of Primary Productivity And Limnological Patterns In Lake Mead, Lorne G. Everett

Publications (WR)

The temporal and spatial changes in chemical and biological properties of Lake Mead have been investigated, thereby indicating the sources of water pollution and the time of highest pollution potential. Planktonic organisms have been shown to indicate the presence of water problems. Macro- and micro-nutrient analyses have shown that primary productivity is not inhibited by limiting concentrations. A mathematical model has been developed, tested with one set of independent data, and shown worthy of management utility. Although the model works very well for the Lake Mead area, the physical reality of the Multiple Linear Regression equation should be tested on …


Report On Water Pollution Problems In Las Vegas Wash And Las Vegas Bay, Environmental Protection Agency Nov 1971

Report On Water Pollution Problems In Las Vegas Wash And Las Vegas Bay, Environmental Protection Agency

Publications (WR)

This report was prepared by the Federal Water- Quality Administration, Pacific Southwest Region, now the Environmental Protection Agency (EPA), Region IX, at the request of the State of Nevada, Department of Health, Welfare, and rehabilitation. In a letter, dated December 5, 1969, this agency asked for technical assistance, as authorized by the Federal Water Pollution Control Act, in developing discharge standards appropriate for Las Vegas Bay, Lake Mead, and the Lower Colorado River. The subsequent study was performed by EPA from January through August, 1970. The establishment of Nevada State Water Quality Standards for these waters will enable responsible officials …


A Preliminary Ecological Study Of Areas To Be Impounded In The Salt River Basin Of Kentucky, Louis A. Krumholz, Stuart E. Neff, Edmond J. Bacon, Jerry S. Parsons, John D. Woodling Oct 1971

A Preliminary Ecological Study Of Areas To Be Impounded In The Salt River Basin Of Kentucky, Louis A. Krumholz, Stuart E. Neff, Edmond J. Bacon, Jerry S. Parsons, John D. Woodling

KWRRI Research Reports

This report includes work that is an extension of Project No. B-005-KY as reported in Research Report No. 43 of the University of Kentucky Water Resources Institute. That project was initiated in April 1968 as Project No. A-019-KY with principal emphasis on physical, chemical, and biological characteristics of the main stem of the Salt River upstream from the proposed damsite for Taylorsville Lake, an impoundment of about 3, 600 acres at seasonal pool. The report includes descriptions of an additional 13 stations along the stream, bringing to 38 the number of permanent collecting sites.

Values for dissolved oxygen ranged from …


A Preliminary Ecological Study Of Areas To Be Impounded In The Salt River Basin Of Kentucky, Louis A. Krumholz Sep 1971

A Preliminary Ecological Study Of Areas To Be Impounded In The Salt River Basin Of Kentucky, Louis A. Krumholz

KWRRI Research Reports

This report covers work that is an extension of Project No. A-019-KY. A series of 25 sampling stations was established in the mainstream and tributaries of the Salt River that extend from the source of the stream in Boyle County to a few miles below the site of Taylorsville Darn in Spencer County. Sampling for water chemistry and biota was carried out semimonthly. Data on temperature, oxygen, depth, and discharge, along with analyses for cations (Ca, Mg, Fe, Mn) and anions (PO4, NO3, NO2, CO3, HCO3) have been accumulated and …


A Conceptual Draft Of A Dynamic Hydro-Biological Model For Lake Mead, L. G. Everett, Bureau Of Reclamation Apr 1971

A Conceptual Draft Of A Dynamic Hydro-Biological Model For Lake Mead, L. G. Everett, Bureau Of Reclamation

Publications (WR)

Food and energy transformation in an aquatic system must be understood in order to develop a simulation approach. This report provides a comprehensive study of an aquatic ecosystem. The objectives of this report are to show: (1) the biological relationships in an aquatic system (2) the role of nutrients in the biological cycle (3) the role of abiotic factors in a limnetic environment (4) the status of the art of "Eutrophication modeling".


Control Of Water Resources In W.A, T C. Calder Jan 1971

Control Of Water Resources In W.A, T C. Calder

Journal of the Department of Agriculture, Western Australia, Series 4

Use of underground and surface water is controlled so that the supplies are available to the general benefit of all domestic, industrial and agricultural users in a particular area.

Water is a valuable resource and its contamination and wastage must be avoided. This article outlines the provisions of the Rights in Water Act which is designed to protect water supplies from undue exploitation, contamination and wastage.


Micronutrients And Biological Patterns In Lake Mead, Hasan K. Qashu, Lorne G. Everett, J. S. Carlson, Bureau Of Reclamation Jan 1971

Micronutrients And Biological Patterns In Lake Mead, Hasan K. Qashu, Lorne G. Everett, J. S. Carlson, Bureau Of Reclamation

Publications (WR)

Progressive increases in concentration of dissolved solids in the Colorado River water from Lake Powell to Imperial Dam seem to alter plankton dynamics and biological productivity of the river. Also, changes in biological productivity and micronutrients concentrations occur within the same reservoir. Development of a digital simulation model to predict micronutrients concentrations and biological productivity is necessary for diagnosing changes in plankton population and effluent-carrying capacity of the system. The objectives of the study are: (1) to determine trace metal balance at different locations in Lake Mead, (2) to measure biological productivity and conduct plankton population counts at each sampling …


The Effect Of Las Vegas Wash Effluent Upon The Water Quality In Lake Mead, D. A. Hoffman, P. R. Tramutt, F. C. Heller, Bureau Of Reclamation Jan 1971

The Effect Of Las Vegas Wash Effluent Upon The Water Quality In Lake Mead, D. A. Hoffman, P. R. Tramutt, F. C. Heller, Bureau Of Reclamation

Publications (WR)

This study developed from observations made during an earlier study on Lake Mead which was reported in CHE-70, Water Quality Study of Lake Mead. Results from that study indicated that poor-quality water was flowing into the Las Vegas Bay reach of Boulder Basin, Lake Mead. Also reports of deteriorating water quality, resulting in taste and odors in domestic water supplies taken from Boulder Basin as well as a reduction in the attractiveness of Las Vegas Bay for recreational uses caused by aquatic plants and algae blooms, indicated a need for a concentrated study concerning the effects of flows from Las …