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Full-Text Articles in Environmental Indicators and Impact Assessment

The Role Of Nannoplankton In The Phytoplankton Dynamics Of Four Colorado River Reservoirs (Lakes Powell, Mead, Mohave, And Havasu), Jeffrey John Janik May 1984

The Role Of Nannoplankton In The Phytoplankton Dynamics Of Four Colorado River Reservoirs (Lakes Powell, Mead, Mohave, And Havasu), Jeffrey John Janik

Publications (WR)

Phytoplankton species composition and community size structure were studied in four warm-monomictic Colorado River reservoirs; lakes Powell, Mead, Mohave, and Havasu from March 1981 to February 1982. Sampling was done at approximately monthly intervals from several stations in each reservoir. The Utermohl technique was used to enumerate phytoplankton. The phytoplankton assemblage was divided into the following six size classes using microscopic techniques; netplankton (>64 um), and nannoplankton (>5, 5-11, 12-21, 22-44, and 45-64 um).

Total phytoplankton biomass and community size structure were different among these four reservoirs with considerable spatial and temporal variation present. Average reservoir-wide areal weighted …


Fundy Tidal Power Development : Preliminary Evaluation Of Its Environmental Consequences To The Resources Of The State Of Maine, Bigelow Laboratory For Ocean Sciences Apr 1984

Fundy Tidal Power Development : Preliminary Evaluation Of Its Environmental Consequences To The Resources Of The State Of Maine, Bigelow Laboratory For Ocean Sciences

Maine Collection

Fundy Tidal Power Development : Preliminary Evaluation of Its Environmental Consequences to the Resources of the State of Maine

A Report to the Maine State Planning Office by the Bigelow Laboratory for Ocean Sciences, April, 1984.

"Technical Report No. 35 - Bigelow Laboratory for Ocean Sciences, West Boothbay Harbor, Maine - A Division of Northeastern Research Foundation, Inc."

Contents: Executive Summary / Introduction / Methods / Physical and Biological Consequences / Socio-Economic Consequences / Research Needs / Bibliography / Appendix I. Written Comments on Greenberg Model


Las Vegas Wash Multispectral Scanner Survey, T. H. Mace, M. V. Olsen, Environmental Protection Agency Feb 1984

Las Vegas Wash Multispectral Scanner Survey, T. H. Mace, M. V. Olsen, Environmental Protection Agency

Publications (WR)

At the request of the U.S. Bureau of Reclamation, Boulder City, Nevada, the U.S. Environmental Protection Agency's Environmental Monitoring Systems Laboratory at Las Vegas collected multispectral scanner imagery of Las Vegas Wash on October 1, 1982. A combined maximum likelihood classification and editing procedure was used to classify the multispectral scanner imagery into 12 categories of land cover. The classification identified four categories of marsh vegetation, one category of riparian, two categories of mixed scrub, and two desert categories. Turbid water and cultivated land formed an "other" category. Area tabulations were formed by georeferencing the classification to the Universal Transverse …


Damage Report Of The West Coastal Wildfire (Jan 16-21, 1984) And Its Effects On The Western Australian Beekeeping Industry, R C. Burking, A. C. Kessell Jan 1984

Damage Report Of The West Coastal Wildfire (Jan 16-21, 1984) And Its Effects On The Western Australian Beekeeping Industry, R C. Burking, A. C. Kessell

Apiculture research reports

No abstract provided.


Las Vegas Wash Advanced Water Quality Study: Final Report, Richard A. Roline, James J. Sartoris, U.S. Bureau Of Reclamation Jan 1984

Las Vegas Wash Advanced Water Quality Study: Final Report, Richard A. Roline, James J. Sartoris, U.S. Bureau Of Reclamation

Publications (WR)

The purpose of the Las Vegas Wash Advanced Water Quality Study is to determine the existence, extent, and mechanisms of nutrient and toxin stripping in Las Vegas Wash under present conditions and under future conditions, both with and without construction of the proposed salinity control unit as described by the Bureau of Reclamation (USBR, 1982b). This study was performed for the Lower Colorado Region Division of Planning by personnel of the Environmental Sciences Section of the Division of Research and Laboratory Services, E&R Center, Denver, Colorado. Work on the study began in February 1983. The general approach adopted for this …


Applications Of Aerial Imagery In Identification Of Natural Areas, Kendall Duane Wessel Jan 1984

Applications Of Aerial Imagery In Identification Of Natural Areas, Kendall Duane Wessel

Dissertations and Theses @ UNI

There is current interest in utilizing aerial imagery to obtain information on natural vegetation. The purpose of this study is to utilize and evaluate commonly available aerial imagery to identify potential natural areas suitable for preservation and to initiate development of a procedure for imagery interpretation to meet this goal.

Clayton County, located in the northeastern quarter of the state of Iowa, was selected for study because it is dissected by steep, narrow stream valleys that are unsuitable for cultivation and may still possess native vegetation of a quality suitable for preservation.

Baseline or control communities were selected from known …


Water Quality Trends In The Las Vegas Wash Wetlands, F. A. Morris, L. J. Paulson Jan 1983

Water Quality Trends In The Las Vegas Wash Wetlands, F. A. Morris, L. J. Paulson

Publications (WR)

The Las Vegas Wash is a wetlands ecosystem that acts to buffer the effects of wastewater discharges on the receiving waters of Lake Mead. The wash is the terminus for the 4,144 km2 Las Vegas Valley drainage basin, emptying into Las Vegas Bay of Lake Mead (Colorado River). It is in the northern Mojave desert, which receives an average of only 10 cm of rainfall annually. The Las Vegas Wash is technically an artificial wetland supported almost entirely by the perennial flows from sewage treatment plants. These flows contribute an average of 3-7 t of nutrients (nitrogen and phosphorus) and …


The Effects Of Limited Food Availability On The Striped Bass Fishery In Lake Mead, John R. Baker, Larry J. Paulson Jan 1983

The Effects Of Limited Food Availability On The Striped Bass Fishery In Lake Mead, John R. Baker, Larry J. Paulson

Publications (WR)

The original range of striped bass (Morone saxatilis) was along the Atlantic Coast. They were introduced into the lower Sacramento River in 1879 and are now also found along the Pacific Coast. A landlocked striped bass fishery was established in Santee-Cooper Reservoir, South Carolina, in 1954, and they have since been introduced into numerous other reservoirs, including Lake Havasu, Lake Mead and Lake Powell on the Colorado River. Striped bass were introduced into Lake Mead in 1969 in response to declines in the largemouth bass (Micropterus salmoides) fishery that occurred during the 1960s and in order to further utilize the …


Use Of Hydroelectric Dams To Control Evaporation And Salinity In The Colorado River System, Larry J. Paulson Jan 1983

Use Of Hydroelectric Dams To Control Evaporation And Salinity In The Colorado River System, Larry J. Paulson

Publications (WR)

The main stem reservoirs on the Colorado River comprise one of the largest and most heavily used freshwater bodies in the nation. These reservoirs (Lake Powell, Lake Mead, Lake Mohave and Lake Havasu) can store up to 53,590,400 acre-feet of water at their maximum capacities. Nonetheless, local water shortages still exist in some areas of the Colorado River Basin. There is also concern that salt concentrations are approaching levels that could severely affect municipal and agricultural uses. Water shortages will become even more acute as demands for water increase with continued urban and agricultural development in the basin. Water conservation …


Historical Patterns Of Phytoplankton Productivity In Lake Mead, Richard T. Prentki, Larry J. Paulson Jan 1983

Historical Patterns Of Phytoplankton Productivity In Lake Mead, Richard T. Prentki, Larry J. Paulson

Publications (WR)

Lake Mead was impounded in 1935 by the construction of Hoover Dam. The Colorado River was unregulated prior to then and therefore was subjected to extreme variations in flows and suspended sediment loads. Hoover Dam stabilized flows and reduced suspended sediment loads downstream, but Lake Mead still received silt-laden inflows from the upper Colorado River Basin. The Colorado River contributed 97% of the suspended sediment inputs to Lake Mead, and up to 140 x 1O6 metric tons (t) entered the reservoir in years of high runoff. Most of the sediments were deposited in the river channel and formed an …


The Influence Of Lake Powell On The Suspended Sediment-Phosphorus Dynamics Of The Colorado River Inflow To Lake Mead, T. D. Evans, Larry J. Paulson Jan 1983

The Influence Of Lake Powell On The Suspended Sediment-Phosphorus Dynamics Of The Colorado River Inflow To Lake Mead, T. D. Evans, Larry J. Paulson

Publications (WR)

The Colorado River has been successively modified by the construction of several reservoirs, beginning in 1935 with the formation of Lake Mead by Hoover Dam. These reservoirs are located in a chain, and each one has an influence on the nutrient dynamics and productivity of the river and downstream reservoir. Lake Mead derives 98% of its annual inflow from the Colorado River. Historically, the Colorado River inflow was unregulated into Lake Mead. Regulation occurred in 1963, when Lake Powell was impounded by the construction of Glen Canyon Dam, approximately 450 km upstream. The formation of Lake Powell drastically altered the …


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 …


Report No 49 - Geographically Restricted Plants Of Southern Western Australia, Barbara L. Rye Jan 1982

Report No 49 - Geographically Restricted Plants Of Southern Western Australia, Barbara L. Rye

Fisheries Research Reports

This publication lists 527 angiosperm species native to southern western Australia whose known geographical ranges are less than 100 kilometres long. A further 128 angiosperms are listed with geographical ranges between 100 and 160 kilometres. No fern or gymnosperm species in the region are known to be geographically restricted.

Apart from the presently unnamed species, a large majority of the rare plants of southern Western Australia are believed to be listed, including 86 of the species that have been gazetted as rare flora.

Less than 40% of the listed species are known to occur on conservation reserves and less than …


The Voluntary Water Quality Monitoring Program : 1982 Project Report, Barbara Welch, Judy Potvin, Mary Ellen Dennis Jan 1982

The Voluntary Water Quality Monitoring Program : 1982 Project Report, Barbara Welch, Judy Potvin, Mary Ellen Dennis

Maine Collection

The Voluntary Water Quality Monitoring Program : 1982 Project Report

by Barbara Welch, Judy Potvin & Mary Ellen Dennis

Division of Environmental Evaluation and Lake Studies, Maine Department of Environmental Protection, Augusta, Maine 1982.

Contents: Understanding Maine's Lakes and Ponds / Acknowledgement / Temperature / Dissolved Oxygen / Other Measures of Lake Water Quality / Nutrients / Algae and Chlorophyll a / Transparency / Morphometry / Sampling / Protection / Classification / Answers to Most Frequently Asked Questions / Glossary of Terms / Appendix A : Maximum, Minimum, and Mean Values / Appendix B : Phosphate Content of Common Cleansers …


Algal Dynamics In A Cypress Stand In The Seasonally Flooded Great Dismal Swamp, Joseph A. Atchue Iii Oct 1981

Algal Dynamics In A Cypress Stand In The Seasonally Flooded Great Dismal Swamp, Joseph A. Atchue Iii

Biological Sciences Theses & Dissertations

The dynamics of epiphytic algae and phytoplankton were studied at a cypress stand in the Great Dismal Swamp, Virginia. Mean epiphytic algal biomass was 19.9 g m-2 and mean planktonic biomass was 3.4 g m-2.Nutrient concentrations in the epiphytic algae and the litter were determined. The algae had mean concentrations of 1.67% and 0.18%. They were found to immobilize as much as 0.5 g N m-2 and 0.06 g P m-2. This suggests that the algae are important as nutrient conservers. The phytoplankton were composed primarily of Bacillariophyceae. They exhibited a more or less …


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 …


Municipal Sewage Treatment: Problems And Considerations, George R. Johnson Apr 1981

Municipal Sewage Treatment: Problems And Considerations, George R. Johnson

Marine Affairs Theses and Major Papers

The coastal areas are vital to the economic and physical well being of the United States. Virtually every facet of our way of life is related in some fashion to these coastal areas. Ocean borne transportation moves not only vast quantities of raw materials, but also many of the intermediate and final products that are then manufactured to their related market areas. Fisheries provide vast amounts of food and employment for many of our people. In addition, the coasts are a continuing source of enjoyment and recreation for millions of our citizens. Coastal waters provide much of the water necessary …


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 41 - A Survey Method For Identifying Roadside Flora Suitable For Conservation In Western Australia, John K. Scott Jan 1981

Report No 41 - A Survey Method For Identifying Roadside Flora Suitable For Conservation In Western Australia, John K. Scott

Fisheries Research Reports

A survey method for identifying flora suitable for conservation alongside roads in south-western Australia was derived from an examination of characteristics of road verges. Two roads, from Midland to Toodyay and from Armadale to Bunbury, were examined. Width of verge, weed cover, soil disturbance, vegetation structure, presence of public utilities, evidence of fire and the type of adjoining land were measured at one mile (1.6 km) intervals on both sides of the road. Also recorded were aesthetic qualities such as stands of beautiful trees and sites of special interest, e.g. the presence of rare plants.

Three variables, percentage weed cover, …


The Distribution And Relative Abundance Of Aquatic Oligochaeta In The Upper Cache River System, Southern Illinois, In Relation To Water Quality, Mark Julian Wetzel Jan 1981

The Distribution And Relative Abundance Of Aquatic Oligochaeta In The Upper Cache River System, Southern Illinois, In Relation To Water Quality, Mark Julian Wetzel

Masters Theses

Species composition, distribution, abundance, and water quality relationships of aquatic oligochaetes occurring in the upper Cache River system, southern Illinois were investigated. Forty-two taxa of oligochaetes including 16 naidids, 22 tubificids and representatives of the families Aeolosomatidae, Branchiobdellidae, Enchytraeidae, and Lumbriculidae were collected. Four species of oligochaetes new to Illinois, Limnodrilus psammophilus Loden, L. rubripenis Loden, Psammoryctides (Spencerius) californianus Brinkhurst, and Haemonais waldvogeli Bretscher were collected during this study. Another species of Limnodrilus new to science is reported here, as yet undescribed. The thesis that aquatic oligochaetes can be used as true water quality indicator organisms is rejected. It is …


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 …


Report No 40 - Commercially Exploited Vacsular Plants Native In Western Australia: Census, Atlas And Preliminary Assessment Of Conservation Status, Barbara L. Rye, S. D. Hopper, L. E. Watson Jan 1980

Report No 40 - Commercially Exploited Vacsular Plants Native In Western Australia: Census, Atlas And Preliminary Assessment Of Conservation Status, Barbara L. Rye, S. D. Hopper, L. E. Watson

Fisheries Research Reports

A census and atlas is provided of 1 119 native Western Australian plant species which were commercially exploited during 1977-79 in the cut plant, nursery or seed trades. The exploited species are concentrated in the vicinities of Perth and Albany, the two matin centres for the wildflower industry. Preliminary assessments of the conservation status of the exploited species are provided. Approximately r200 species are regarded as being rare, geographically or poorly collected, and further studies are recommended for these species to determine whether they are in danger of overexploitation.


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.


Metals In Apple Cider Produced And Marketed In Connecticut, Dennis W. Hill, Thomas R. Kelley, Gale R. Morrow, Sylvia W. Matiuck Dec 1979

Metals In Apple Cider Produced And Marketed In Connecticut, Dennis W. Hill, Thomas R. Kelley, Gale R. Morrow, Sylvia W. Matiuck

Storrs Agricultural Experiment Station

No abstract provided.