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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 …


The Prairie Naturalist Volume 13, Number 2. June 1981 Jun 1981

The Prairie Naturalist Volume 13, Number 2. June 1981

The Prairie Naturalist

HERPETOFAUNA OF MORMON ISLAND PRESERVE, HALL COUNTY, NEBRASKA ▪ S. M. Jones, R. E. Ballinger and J. W Nietfeldt

COYOTE USE OF PLAYAS IN THE TEXAS HIGH PLAINS ▪ R. W. Whiteside and F. S. Guthery

NEW RECORD OF THE LEAST WEASEL IN WYOMING ▪ M. R. Stromberg, D. E. Biggens and M. Bidwell

STATUS OF AMERICAN WOODCOCK IN NEBRASKA WITH NOTES ON A RECENT BREEDING RECORD ▪ G. R. Lingle

WINTER FOODS OF THE PINE GROSBEAK IN EASTERN NORTH DAKOTA ▪ R. C. Reigh

SEASONAL VARIATION IN HOME RANGE OF A FEMALE BADGER (Taxidea taxus) ▪ R. …


Volume 5, Number 5 (May 1981), The Solar Ocean Energy Liaison May 1981

Volume 5, Number 5 (May 1981), The Solar Ocean Energy Liaison

The OTEC Liaison

No abstract provided.


The Probe, Issue 13 - May 1981 May 1981

The Probe, Issue 13 - May 1981

The Probe: Newsletter of the National Animal Damage Control Association

Content:
Prexy’s Corner
Disneyworld, D.C.
An Animal Damage Identification Guide for Massachusetts
Bird Problems in Agriculture
Let’s Hit the Antis Where They Live – Right in the Legislature!
Oregon Revisited
WLFA Update
The problem with feral pigs in San Benito County (CA)
Dr. Donald A. Spencer, Regional Director VI
Milton Caroline, Regional Director IV
A Study of the Foraging Habits of Quits at the Montgomery County Landfill, Rockville, Maryland
Harvey O. Edwards – Memoir
Which Risks are Acceptable?
Illegally killed elk being poached just for their antlers
Recommendations for an effective ADC program


Higher Plant Acclimation To Solar Ultraviolet-B Radiation, Ronald Robberecht May 1981

Higher Plant Acclimation To Solar Ultraviolet-B Radiation, Ronald Robberecht

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Plant acclimation to natural and intensified solar UV-B irradiance was investigated in three species, Oenothera stricta Ledeb., Rumex obtusifolius L., and R. patientia L. The objectives of this study were to determine: (1) the relationship between plant sensitivity and epidermal UV attenuation, (2) the effect of phenotypic changes in the leaf epidermis, resulting from UV-B exposure, on plant sensitivity to UV radiation, and (3) the plasticity of these changes in the epidermis leading to plant acclimation to UVB radiation.

Epidermal UV transmittance was found to differ in magnitude and spectral distribution among the three species examined in this study. Epidermal …


Fall Regrowth Of Crested Wheatgrass And Fourwing Saltbush, Noor Mohammad May 1981

Fall Regrowth Of Crested Wheatgrass And Fourwing Saltbush, Noor Mohammad

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

During 1980-81, studies with crested wheatgrass (Agropyron desertorum) and fourwing saltbush (Atriplex canescens) were conducted in controlled environment growth chambers as well as under field conditions to achieve the following objectives:

1. To determine the effect of nitrogen fertilizer on the water use efficiency.

2. To determine the effects of various temperature, water stress and nitrogen treatments on the productivity, nitrogen content and carbohydrate reserves.

3. To determine the effects of N fertilization on fall and spring regrowth.

Crested wheatgrass and fourwing saltbush plants were maintained in three growth chambers for 60 days under three temperature …


Seasonal Temperature Preference Of Adult Mountain Whitefish, Prosopium Williamsoni, Jean M. Ihnat May 1981

Seasonal Temperature Preference Of Adult Mountain Whitefish, Prosopium Williamsoni, Jean M. Ihnat

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Temperatures selected seasonally by adult mountain whitefish were measured in the laboratory in a horizontal gradient. Final preferendum estimates, based on acute (3-hour) preference tests conducted with fish acclimated to 5, 10, and 15 C each season, were 17.7 C (pre-spawning), 11.9 C (post-spawning), 9.9 C (winter), and 16.3 C (spring). Seasonal influence on temperature selection was evident on the basis of differences in final preferenda, covariance analysis of responses of laboratory-acclimated fish, and temperature selection by fish held at ambient river temperatures. Post-spawning and winter groups selected lower temperatures than did pre-spawning and spring groups. Pre-spawning fish selected temperatures …


Some Morphological And Chemical Responses Of Blackbrush (Coleogyne Ramosissima) To Goat Browsing: Influences On Dietary Blackbrush Selection By Goats And Cattle, Frederick D. Provenza May 1981

Some Morphological And Chemical Responses Of Blackbrush (Coleogyne Ramosissima) To Goat Browsing: Influences On Dietary Blackbrush Selection By Goats And Cattle, Frederick D. Provenza

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Domestic goats were used to modify the growth form of blackbrush, a spinescent shrub occurring in nearly monospecific stands on several million hectares of rangeland in the southwestern United States. The objective of this research was to evaluate goat browsing as a means of improving these rangelands for cattle. Winter goat browsing stimulated spring twig growth from basal and axillary buds which resulted in increased production.

Twig production by heavily browsed plants (>95 percent removal of current season's twigs) was a function of precipitation, soil depth, branch location on the plant, and period of rest after browsing. As precipitation …


Natural Pastures Of The Macquarie Region Of New South Wales: Their Origin, Composition And Management, David Leslie Michaelk May 1981

Natural Pastures Of The Macquarie Region Of New South Wales: Their Origin, Composition And Management, David Leslie Michaelk

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Two experiments were conducted in the semi-arid (400 millimeter annual rainfall) Macquarie region of New South Wales, Australia, at the Trangie Agricultural Research Station (31° 59'S; 147° S7'E), to examine (a) the way botanical parameters can be used to separate grazing and climatic impacts on range vegetation, and (b) how this delineation affects application of range science tenets (site, condition and trend) to different pasture types.

Two range sites were studied: Site 1, a light soil type, was dominated by annual grasses, legumes and forbs, whereas perennial grasses (mainly Chloris acieularis and Chloris truncata) dominated the heavy soils of …


Effect Of Mild Water Stress And Enhanced Ultraviolet-B Irradiation On Leaf Growth Of Rumex Obtusifolius L. And Rumex Patientia L. (Polygonaceae)., Steve R. Holman May 1981

Effect Of Mild Water Stress And Enhanced Ultraviolet-B Irradiation On Leaf Growth Of Rumex Obtusifolius L. And Rumex Patientia L. (Polygonaceae)., Steve R. Holman

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Leaves of Rumex obtusifolius L. and R. patientia L.were exposed to combinations of mild water stress and enhanced ultraviolet-B irradiation during their ontogeny. Two UV-B treatments (enhanced UV-B and control) and three water stress treatments (-0.0 MPa, -0.2 MPa and -0.4 MPa rooting medium matric potentials) were employed. The impact of the stress interaction was assessed on the basis of changes in leaf area, average adaxial epidermal cell size, and total number of adaxial epidermal cells per leaf. Although the level of UV-B irradiation applied was insufficient to significantly alter leaf growth at any given water stress, UV-B did interact …


The Energy Expenditure Of Heifers Grazing Crested Wheatgrass Rangeland In West-Central Utah, Kris M. Havstad May 1981

The Energy Expenditure Of Heifers Grazing Crested Wheatgrass Rangeland In West-Central Utah, Kris M. Havstad

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The free-roaming ruminant requires energy for the demands of vii grazing, traveling and thermoregulation that are not required by its confined counterpart. Literature estimates of these additional costs range from 10 to 170 percent above maintenance. The uncertain magnitude of this increased demand and the factors that contribute to it impede the ability of the rangeland ruminant nutritionist to establish guidelines for the energy requirements of the free-roaming herbivore. This study was designed to estimate the energy expenditure of yearling Angus heifers while grazing a declining supply of available crested wheatgrass forage (Agropyron cristatum) on rangeland in west-central …


Lifestyle As A Determinant Of Participation Among Dispersed Forest Recreationists, John R. Butler May 1981

Lifestyle As A Determinant Of Participation Among Dispersed Forest Recreationists, John R. Butler

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study assesses the usefulness of lifestyle as a determinant of outdoor recreation behavior. Two objectives of the study are: (1) develop an operationalized concept of lifestyle that is based on theory, and (2) apply this concept in a model which uses lifestyle as a variable influencing recreation behavior.

The first objective was approached through an integrative review of the literature. Lifestyle was set in context of cultural theory. The basic postulate of the proposed theory of lifestyle is: If an individual's lifestyle is similar to that of another, certain social psychological processes are similar. Therefore, their patterns of needs, …


The Rhode Island Quahogger: Candidate For The List Of Endangered Species?, James M. Korney Apr 1981

The Rhode Island Quahogger: Candidate For The List Of Endangered Species?, James M. Korney

Marine Affairs Theses and Major Papers

It is the hypothesis of this paper that today the livelihood of the independent Narragansett Bay quahogger is faced with two potentially dangerous threats; water pollution in upper Narragansett Bay and the prospect of an expanding aquaculture industry in the lower bay. Unless the state of Rhode Island properly interprets and enforces existing state legislation to protect the quahoggers interests, his very livelihood will be jeoprodized. This paper will examine the legal, political, economic, and environmental affects of water pollution in upper Narragansett Bay and an expanding aquaculture industry in the lower bay in their relation to the Rhode Island …


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 …


The Viability Of Imported Liquified Natural Gas As An Energy Resource, Richard L. Dick Apr 1981

The Viability Of Imported Liquified Natural Gas As An Energy Resource, Richard L. Dick

Marine Affairs Theses and Major Papers

As the United States enters the 1980's, the need for secure and efficient energy sources is rapidly moving to the forefront of our foreign and domestic policies. It is apparent that our existence, as well as that of our allies, is closely tied to the ability to secure energy resources. The importation of Liquified Natural Gas (LNG), by specially designed ships, from oil exporting nations to energy consuming nations has been a highly touted energy resource. United States importation of LNG is not a cost effective energy resource due to: (1) dependence on foreign sources, (2) transportation costs including "hidden" …


A Comparison Of Reproductive Strategies Among Marine Snakes, Cliff A. Lemen, Harold K. Voris Apr 1981

A Comparison Of Reproductive Strategies Among Marine Snakes, Cliff A. Lemen, Harold K. Voris

School of Natural Resources: Faculty Publications

(1) Gravid females representing fourteen species of marine snakes were collected from four localities along the coast of Malaysia in 1975. The average clutch size ranged from 2.9 to 17.8 but most species had between three and seven young. The number of young produced and the size of gravid Lapemis hardwickii differed significantly at two sites in the Straits of Malacca. Eight species showed a significantly positive relationship between the number of oviducal eggs and female weight. The rate of infertility among ten species ranged from 4.5 to 20%.

(2) Sex ratios in the collections varied significantly through time and …


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


Storm-Sewer Input Of Heavy Metals Into An Urban Lake Environment, George A. Duba Apr 1981

Storm-Sewer Input Of Heavy Metals Into An Urban Lake Environment, George A. Duba

Dissertations

The purpose of this study was to measure the concentration of lead, cadmium, zinc and copper in runoff entering an urban lake ecosystem and to measure the distribution of these metals in selected tropic levels of the lake.

Fisk Lake was chosen as the study site and is located in East Grand Rapids, Michigan. Samples were collected of stormwater, rainwater and lakewater together with substrate, aquatic macrophytes Peltandra virginica, chironomid larvae, Chironomidae, snails Physa, and eight species of fish, Ictalurus nebulosus, Esox lucius, Lepomis gibbosus, L. macrochirus, Pomoxis nigromaculatus, Micropterus salmoides, Catostomus commersoni, and Perca flavescens. All samples were collected …


Continuous Flow Nutrient Bioassays With Natural Phytoplankton Populations Collected In Hillsborough Bay, Florida, City Of Tampa Department Of Sanitary Sewers Mar 1981

Continuous Flow Nutrient Bioassays With Natural Phytoplankton Populations Collected In Hillsborough Bay, Florida, City Of Tampa Department Of Sanitary Sewers

Reports

The enclosure system chosen for these experiments was continuous and similar to one described by Jones, Tett, Wallis, and Wood (1978a sn b). They successfully maintained for 41 days in the laboratory, with reasonable constant diversity, a natural phytoplankton community from a Scottish Sea-loch.


Final Report Of The Hillsborough Bay Water Quality Monitoring Program, City Of Tampa Department Of Sanitary Sewers Mar 1981

Final Report Of The Hillsborough Bay Water Quality Monitoring Program, City Of Tampa Department Of Sanitary Sewers

Reports

The report presented here is the final communication of data collected during the first year and a half of plant operation at variance standards. In addition, earlier data collected by the City of Tampa are also presented in this report in order to give background information of conditions existing prior to operation under the variance (Appendix C). The earlier data may also describe long term trends and normal seasonal cycles occurring in the bay.


Social Behavior Of The Pine Vole (Pitymys Pinetorum): I. Activity Patterns Of Mated Pine Voles In Semi-Natural Environments, Philip O. Renzullo, Milo E. Richmond Mar 1981

Social Behavior Of The Pine Vole (Pitymys Pinetorum): I. Activity Patterns Of Mated Pine Voles In Semi-Natural Environments, Philip O. Renzullo, Milo E. Richmond

Eastern Pine and Meadow Vole Symposia

The root damage resulting from pine vole (Pitymys pinetorum) infestation of apple orchards remains a major vertebrate pest problem. Currently, research effort is being directed at habitat management and at toxic bait development and application as two potentially cost-effective methods for control of these rodents. Recently, investigations have begun into the detailed relationships between the pine vole's physiology and it's habitat in an effort to understand and perhaps disrupt the seemingly ideal balance achieved by the animal in apple orchard situations. In addition to these approaches, which have possible immediate application, one area of pine vole biology that …


Growth And Development Rates Of Microtus Pinetorum Under Different Photoperiods, T. L. Derting, J. A. Cransford Mar 1981

Growth And Development Rates Of Microtus Pinetorum Under Different Photoperiods, T. L. Derting, J. A. Cransford

Eastern Pine and Meadow Vole Symposia

Photo-period and nutrition are important variables affecting reproductive activity and growth in many rodents. Field and laboratory studies indicate that long photo-period (spring-summer) cause Increased growth while short photo-periods (fall-winter) inhibit these processes. In the montane vole (Microtus montanus) recently weaned animals gain weight at a much lower rate under short photo-periods or in total darkness than under long photo-periods (Vaughan et al., 1973; Peterborg, 1978). Adult M. montanus had more offspring and larger mean litter sizes under LD 18:6 than LD 6:18 (Pinter & Negus, 1965). Similarly, long (LD 16:8) or increasing photo-periods stimulated the onset of …


Frontmatter Mar 1981

Frontmatter

Eastern Pine and Meadow Vole Symposia

Frontmatter


Proceedings Of The Fifth Eastern Pine And Meadow Vole Symposium, Gettysburg, Pa, March 4-5, 1981 Mar 1981

Proceedings Of The Fifth Eastern Pine And Meadow Vole Symposium, Gettysburg, Pa, March 4-5, 1981

Eastern Pine and Meadow Vole Symposia

Entire symposium.

HIGHLIGHTS OF THE FIFTH EASTERN PINE AND MEADOW VOLE SYMPOSIUM

The Fifth Eastern Pine and Meadow Vole Symposium was held at the Sheraton Inn-Gettysburg, Gettysburg, Pennsylvania March 4 and 5, 1981, for the purpose of assessing the current status of research, extension, and industry programs relating to the problem of vole damage to fruit trees. The meeting was intended to create a problem solving atmosphere in which growers; various governmental agencies such as EPA, USDA, USDI; the chemical industry; and university personnel could observe the cur¬rent thrusts of research and extension programs and their potential impact on future …


Colonization Of An Abandoned Orchard By Pine Voles (Microtus Pinetorum), Jack A. Cranford, J. Harrison, T. L. Derting Mar 1981

Colonization Of An Abandoned Orchard By Pine Voles (Microtus Pinetorum), Jack A. Cranford, J. Harrison, T. L. Derting

Eastern Pine and Meadow Vole Symposia

Habitat selection by pine voles (Microtus pinetorum) has been attributed to cover density (Goertz, 1971; Paul, 1970) soil condition (Benton, 1955; Fisher and Anthony, 1980), and food resources (Noffsinger, 1976; Paul, 1970). Goertz (1971) reported that pine voles were distributed in diverse habitats, but there was a close correlation with height and diversity of grass. Miller and Getz (1969) found populations in sloping upland woods, Benton (1955) in dry woods, and Paul (1970) in hardwood slopes with a close correlation between distribution and amount of ground cover. Soil type has been examined by Benton (1955) and Fisher and …


Effect Of Photoperiod On Activity Patterns In Pine Voles (Microtus Pinetorum), Jack A. Cranford Mar 1981

Effect Of Photoperiod On Activity Patterns In Pine Voles (Microtus Pinetorum), Jack A. Cranford

Eastern Pine and Meadow Vole Symposia

Light is an environmental variable which has considerable effect on small mammal activity patterns. This constantly repeating 24 hour signal provides information on a daily basis and has been shown to synchronize all physiological patterns in an animals existence. Laboratory studies have shown that pine voles are slightly nocturnal (Pearson, 1947) or confined their activity to the hours of twilight and darkness (Werner, 1951). Both authors indicate that activity occurs in bouts of about 1 hour duration followed by an hour of rest. Benton (1955) observed from trapping that more activity occurred at night but cautioned that due to the …


Progress And Prospect Of A Bioenergetic Simulation Model Of Pine Vole Populations, John F. Coyle, Kevin C. Jordan, Alan R. Tipton, Roy L. Kirkpatrick Mar 1981

Progress And Prospect Of A Bioenergetic Simulation Model Of Pine Vole Populations, John F. Coyle, Kevin C. Jordan, Alan R. Tipton, Roy L. Kirkpatrick

Eastern Pine and Meadow Vole Symposia

As reported previously (Coyle and Tipton 1980), we have been engaged in the development of a computerized system which outlines the basic demographic features of a pine vole population. The system, when complete, will hopefully contain four subsystems (biological, spatial, control and economic). This paper will discuss the biological submodel, its development and validity, and prospects for its future.


The Probe, Issue 12 - March 1981 Mar 1981

The Probe, Issue 12 - March 1981

The Probe: Newsletter of the National Animal Damage Control Association

Contents:
Oregon Postmortem
School-age children believe the pronghorn antelope, white-tailed deer and elk are in danger of extinction
Discontinue the production of calcium cyanide
I’ll Take My Steak Bloody Rare, Please! by Barry Gray
NADCA
The Animals’ Revenge
Animal damage to coniferous plantations in Oregon and Washington
Snares
Visual scare devices
CEQ Uses Statistics
Bat Repellents
Norton R. Miner, Region III Director
Meetings of Interest
Sally S. Erdman
Memorial: Harvey Edwards


The Prairie Naturalist Volume 13, Number 1. March 1981 Mar 1981

The Prairie Naturalist Volume 13, Number 1. March 1981

The Prairie Naturalist

EDITOR: Dr. Paul B. Kannowski

BOOK REVIEW EDITOR: Douglas H. Johnson

TABLE OF CONTENTS

WATERFOWL USE OF A MUNICIPAL SEWAGE LAGOON ▪ G-A. D. Maxson

MASS MORTALITY OF MUSSELS FROM SLUMPING ALONG THE RED LAKE RIVER NEAR CROOKSTON, MINNESOTA ▪ A. M. Cvancara, D. J. Brown, D. K. Cudworth, and T. R. Klett

CHRISTMAS BIRD COUNTS FOR NORTH DAKOTA — 1980 ▪ R. N. Randall

BREEDING BIRDS ON WATERFOWL PRODUCTION AREAS IN NORTHEASTERN NORTH DAKOTA ▪ H. F. Duebbert

FURTHER EVIDENCE OF MARSH HAWKS FEEDING ON DUCKS ▪ R. A. Wishert, R. M. Kaminski, and D. W. Soprovich

FIRST NEST …


U.S. Army Corps Of Engineers Public Interest Review: An Evaluation Of Implementation Effectiveness, Sharon Kelberg Jan 1981

U.S. Army Corps Of Engineers Public Interest Review: An Evaluation Of Implementation Effectiveness, Sharon Kelberg

Marine Affairs Theses and Major Papers

The U.S. Army Corps of Engineers is authorized to permit or deny dredge and fill activities in the nation's coastal and wetland regions. Originally, responsible only for the maintenance of navigation, the Corps considered only navigational requirements in decisions to grant or deny permits. Now, however, the Corps must demonstrate, that the "public interest" is served as well. This study examines the scope of the public interest and attempts to evaluate the effectiveness of the program in a particularly controversial project. The initial phase provides evaluation criteria necessary to analyze the application of the public interest review. The second phase …