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Compensatory Response Of Maturing Corn Kernels Following Simulated Damage By Birds, Paul P. Woronecki, Robert A. Stehn, Richard A. Dolbeer Jan 1980

Compensatory Response Of Maturing Corn Kernels Following Simulated Damage By Birds, Paul P. Woronecki, Robert A. Stehn, Richard A. Dolbeer

United States Department of Agriculture Wildlife Services: Staff Publications

(1) A study was made to measure compensatory growth responses and to estimate losses associated with bird damage to maturing corn.
(2) Corn kernels contain 20-40% of their final biomass at the time they are usually consumed by blackbirds.
(3) Very slight compensation of kernel weight occurred following simulated bird damage to tip kernels.
(4) Heavy bird damage, early in kernel development, increased fungal, sprouting, and insect damage before harvest.
(5) Estimates of bird damage, subsequent secondary damage, and compensation were affected by the amount of damage, maturity of the kernels at the time of damage, and environmental factors before, …


Annotated Biobliography Of Remote Sensing For Highway Planning And Natural Resources, An, Daniel L. Civco, William C. Kennard, Michael Wm. Lefor Jan 1980

Annotated Biobliography Of Remote Sensing For Highway Planning And Natural Resources, An, Daniel L. Civco, William C. Kennard, Michael Wm. Lefor

Storrs Agricultural Experiment Station

No abstract provided.


A Technique For Collecting Water Samples Under Extreme Winter Conditions, J. B. Carlson, G. E. Ahlgren Jan 1980

A Technique For Collecting Water Samples Under Extreme Winter Conditions, J. B. Carlson, G. E. Ahlgren

Journal of the Minnesota Academy of Science

No abstract provided.


A Comparative Water Quality Study Of Man-Made Drainage And Natural Streams, Kent W. Boyum Jan 1980

A Comparative Water Quality Study Of Man-Made Drainage And Natural Streams, Kent W. Boyum

Journal of the Minnesota Academy of Science

The effects of man-made drainage systems on the water quality of receiving bodies Is relatively unknown. During the ice-free season of 1979, thirteen drainage ditches and f our rivers were sampled at intervals of three to eight days. With increasing flow, total orthophosphatephosphorous, total Kjeldahl-nitrogen, nitrate-nitrogen and total dissolved solids increased, but not proportionately to f low, with total orthophosphate-phosphorous showing the least proportionality. Variation was observed in each ditch and river when broken down seasonally for each parameter. Generally, when the percentage of flow was greater in one of the three seasons, the percentage of each of the other …


Land-Cover Changes In A River Valley In Blue Earth County, Minnesota, 1938-1974, Corrie Schaffer Cowley Jan 1980

Land-Cover Changes In A River Valley In Blue Earth County, Minnesota, 1938-1974, Corrie Schaffer Cowley

Journal of the Minnesota Academy of Science

The boundary of the Blue Earth River Valley was determined by stereoscopic viewing of 1938-39 aerial photographs. The same boundary was then drawn on corresponding 1974 photographs. All area within the river valley was assigned to one of four land-cover. Comparison of 1938-39 to 1974 shows a decrease of 19 percent in river area, an increase of one percent in row crop area, an increase of 52 percent in tree area, and a decrease of 45 percent in scrub area.


A Survey Of Water Flow In Drainage Ditches And Streams In South Central Minnesota, Clay Pierce, Bill Thompson Jan 1980

A Survey Of Water Flow In Drainage Ditches And Streams In South Central Minnesota, Clay Pierce, Bill Thompson

Journal of the Minnesota Academy of Science

Discharge was monitored on 13 agricultural drainage ditches and 4 small rivers in south central Minnesota. Derived data were categorized by response to hydrologic events and stream order. Stream order was found to be the most reliable predictor of hydrologic event response. Peak flows in drainage ditches were found to correspond to peak flows in rivers.


Master's Degree Program In Marine Biology, Coastal Zone Management, Nova University Jan 1980

Master's Degree Program In Marine Biology, Coastal Zone Management, Nova University

Halmos College of Natural Sciences and Oceanography Course Catalogs

No abstract provided.


Oil And Gas Development On Georges Bank: The Responsibility Of Federal Agencies For Assessment And Mitigation Of Potential Impacts On The Ecosystem, Carolyn A. Griswold Jan 1980

Oil And Gas Development On Georges Bank: The Responsibility Of Federal Agencies For Assessment And Mitigation Of Potential Impacts On The Ecosystem, Carolyn A. Griswold

Marine Affairs Theses and Major Papers

Is it possible to provide adequate protection for the Georges Bank ecosystem as oil and gas exploration begins? The fishing industry and environmentalists say "no," but it is the resource managers who are faced with the task of predicting, assessing and mitigating impacts of development while at the same time managing resources and protecting fishery habitats. Much of this responsibility falls within NOAA; however, legislative mandates and agency responsibilities and goals mean that several other federal agencies are involved as well. This paper is an attempt to describe the potential impacts of oil and gas exploration on the Georges Bank …


Toward Restructuring The Nova Scotia Fishing Fleets As A Result Of The Establishment Of Canada's 200-Mile Fishery Zone, Blaine Gillis Jan 1980

Toward Restructuring The Nova Scotia Fishing Fleets As A Result Of The Establishment Of Canada's 200-Mile Fishery Zone, Blaine Gillis

Marine Affairs Theses and Major Papers

The first step in redeveloping the Nova Scotia fishery is the restructuring and rebuilding of the various Nova Scotia commercial fishing fleets. In this paper, the evolution of the Nova Scotia fishery and fleets is outlined as background for discussion of concerns, issues, and conflicts of the various participants involved in determining the future structureand composition of the Nova Scotia fleet mix. It is concluded that whatsoever the structure and composition of the fleet, there remains the need to protect a critical balance among the various sectors of the Nova Scotia fishery.


Liverpool University Expedition To Jamaica, Donald A. Mcfarlane Jan 1980

Liverpool University Expedition To Jamaica, Donald A. Mcfarlane

WM Keck Science Faculty Papers

During summer 1977, five members of the Liverpool University Potholing Club spent six weeks working and exploring in the caves of Jamaica. The team consisted of Don McFarlane, John Dye, Malcolm Macduff, Mike Roger and Barry Williams, all of whom contributed to this report. The expedition base was at Troy, where the villagers are owed a debt of gratitude for their hospitality. This placed the expedition in the heart of the cave region, and a number of new caves and shafts were discovered and explored. The main discovery was the Still Waters Cave, located near Accompong, where 11,800 feet of …


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.


Adaptative Alteration In Phospholipid Composition Of Plasma Membranes From A Somatic Cell Mutant Defective In The Regulation Of Cholesterol Biosynthesis, Michael Sinensky Jan 1980

Adaptative Alteration In Phospholipid Composition Of Plasma Membranes From A Somatic Cell Mutant Defective In The Regulation Of Cholesterol Biosynthesis, Michael Sinensky

Faculty Publications, Biological Sciences

A somatic cell mutant (CR1) of a Chinese hamster ovary cell (CHO-K1) which has previously been shown to be defective in the regulation of cholesterol biosynthesis accumulates more cholesterol than the parental cell line in plasma membranes. Although such an increase in membrane cholesterol should lead to an increase in the order parameter of these membranes, as measured with an electron spin resonance spin probe, the order parameters of mutant and wild-type plasma membranes are identical--apparently because of an adaptive alteration in membrane phospholipid composition. The phospholipid compositions of mutant and wild-type cell plasma membranes are compared and the mutant …


Fisheries Report No 39 - The Wildlife Of The Proposed Toolonga Nature Reserve, Shark Bay Shire, Western Australia, A. A. Burbidge, P. J. Fuller, K. Cashin Jan 1980

Fisheries Report No 39 - The Wildlife Of The Proposed Toolonga Nature Reserve, Shark Bay Shire, Western Australia, A. A. Burbidge, P. J. Fuller, K. Cashin

Fisheries Research Reports

Following a Cabinet endorsed recommendation by the Environmental Protection Authority in 1975, an area of vacant Crown Zand (the Toolonga Area) was examined during April and September, 1978.

The geology, soils and vegetation of the area are described and annotated lists of mammals, birds, amphibians and reptiles are presented. A small part of the area lies in the South West Botanical Province (Irwin District) but most is in the Eremaean Botanical Province (Carnarvon District). The vertebrate fauna is a mixture of south-western, Shark Bay and arid zone species, but the last predominate.

The Toolonga Area provides an opportunity to protect …


Evaluation Of Areas For Off-Road Recreational Motorcycle Use, Volume I: Evaluation Method, United States Army Corps Of Engineers Jan 1980

Evaluation Of Areas For Off-Road Recreational Motorcycle Use, Volume I: Evaluation Method, United States Army Corps Of Engineers

All U.S. Government Documents (Utah Regional Depository)

To answer user demands for more areas on which to operate off-road recreational motocycles (trailbikes), and to respond to Presidential Executive Orders which require that Federally-owned lands be evaluated for such use, Army land managers need a systematic way of determining land use suitability. This report describes the method developed by the U.S. Army Construction Engineering Research Laboratory (CERL) to help installation personnel comply with the policies, procedures, and criteria of Army Regulation (AR) 210-9, Use of Off-Road Vehicles on Army Lands.


Botanical And Ecological Aspects Of Coastal Raised Peatlands In Maine : And Their Relevance To The Critical Areas Program Of The State Planning Office, Ian A. Worley Jan 1980

Botanical And Ecological Aspects Of Coastal Raised Peatlands In Maine : And Their Relevance To The Critical Areas Program Of The State Planning Office, Ian A. Worley

Maine Collection

Botanical and Ecological Aspects of Coastal Raised Peatlands in Maine : and Their Relevance to the Critical Areas Program of the State Planning Office.

by Ian A. Worley

A Report Prepared for the Maine Critical Areas Program, State Planning Office, 184 State Street, Augusta, Maine 04333.

Planning Report No. 69 (January 1980)

Contents: Foreword / Abstract / Table of Contents / List of Figures / List of Tables / Acknowledgements / Introduction / Natural History and Ecology of the Coastal Raised Peatlands / Selection of Coastal Peatlands Recommended for Evaluation by the Critical Areas Program / General Evaluation of Coastal …


A Statistical Analysis Of The Quality Of Surface Water In Nebraska, R. A. Engberg Jan 1980

A Statistical Analysis Of The Quality Of Surface Water In Nebraska, R. A. Engberg

United States Geological Survey: Publications

This report provides descriptive statistics for 29 chemical or biological constituents for 109 stream sites in Nebraska sampled by the U.S. Geological Survey beginning in 1946. Also provided for each site are regression equations relating specific conductance to each of 12 chemical constituents and a regression equation relating specific conductance to stream discharge. The descriptive statistics are presented by river basins. Water leaving these basins that has the lowest mean specific conductance (266 umho/cm) is from the Niobrara River at Verdel, and water that has the highest (1,890 umho/cm) is from the South Platte River at Roscoe. Statewide, the principal …


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 …


A Limnological Study Of 43 Selected Maine Lakes, Derrill J. Cowing, Matthew Scott Jan 1980

A Limnological Study Of 43 Selected Maine Lakes, Derrill J. Cowing, Matthew Scott

Maine Collection

A Limnological Study of 43 Selected Maine Lakes

by Derrill J. Cowing and Matthew Scott

U.S. Geological Survey : Water-Resources Investigations 80-69

Prepared in cooperation with the Maine Department of Environmental Protection

U.S. Geological Survey, 26 Ganneston Drive, August, Maine 04330


A Study Of Ylide Extractions Of Mercury In Fish And Water Using Cold Vapor Flameless Atomic Absorption Techniques, Howard Vail Jan 1980

A Study Of Ylide Extractions Of Mercury In Fish And Water Using Cold Vapor Flameless Atomic Absorption Techniques, Howard Vail

Masters Theses & Specialist Projects

Cold vapor flameless atomic absorption spectrophotometry is an analytical method used in the determination of mercury. Its sensitivity is less than one part per billion using a 100 milliliter sample, and there are virtually no interferences from other metal ions. The method is best carried out making use of a permanganate-persulfate oxidation step with heat.

The ylide, triphenylphosphoniumcyclopentadienylide (CpPPh3), which extracts mercury almost quantitatively from water, was used in attempts to remove mercury from exposed goldfish. Though not toxic to the fish, CpPPh3 did not significantly lower mercury levels. Evaluation of CpPPh3 as a possible phase …


Iowa Academy Of Science Leadership Directory And Membership Roster, 1980-81, Iowa Academy Of Science Jan 1980

Iowa Academy Of Science Leadership Directory And Membership Roster, 1980-81, Iowa Academy Of Science

Iowa Academy of Science Documents

Contents:

Board of Directors ... 2
Section Chairs ... 4
Section Vice Chairs ... 7
Committees ... 9
Past Presidents ... 21
Award Recipients ... 22
Membership Roster ... 25
Constitution, Article III ... 38


University Of Texas At Tyler Catalog, 1980-1981, University Of Texas At Tyler Jan 1980

University Of Texas At Tyler Catalog, 1980-1981, University Of Texas At Tyler

Catalogs

No abstract provided.


Summer And Fall Ecology Of Gray Patridge In Eastern South Dakota, Jerry W. Hupp Jan 1980

Summer And Fall Ecology Of Gray Patridge In Eastern South Dakota, Jerry W. Hupp

Electronic Theses and Dissertations

Gray partridge (Perdix perdix) nesting biology, summer and fall habitat utilization, home range, and food habits were studied in Brookings County, South Dakota, during 1978-79. Data were collected on a 62 km² study area 16 km northeast of Brookings. Nesting habitats, success, and clutch size were determined from 44 randomly located nests. Most nests (91%) were in grassy roadsides and fencerows. Few birds nested in cover dominated by legume vegetation. Average clutch size of completed nests was 17.8 eggs and nest success was 37%. Mammalian predation was the major cause (50%) of nesting failure. Gray partridge habitat utilization was determined …


The Relationship Of Food Conversion Efficiency And Growth Potential In Juvenile Mosquitofish, Gambusia Affinis, Joseph J. Cech Jr., Michael J. Massingill, Wayne A. Wurtsbaugh Jan 1980

The Relationship Of Food Conversion Efficiency And Growth Potential In Juvenile Mosquitofish, Gambusia Affinis, Joseph J. Cech Jr., Michael J. Massingill, Wayne A. Wurtsbaugh

Watershed Sciences Faculty Publications

New information concerning respiratory metabolic rates of juvenile mosquitofish (i = 915 mg 02 kg-1 h-1 at 20° C) was applied to existing data on mosquitofish respiration and combined with findings on growth and food consumption rates to determine percentages of net ingested energy used for growth and respiration over a 10- 35° C temperature range. The energy percentage used by mosquitofish for respiration was minimized at 25-30° C while that used for growth (= food conversion efficiency) was maximized at the same temperature. A calculated growth potential index, derived from an overall energy balance equation, was also maximized at …


Aspects Of Larval Ecology Of Squilla Empusa (Crustacea, Stomatopoda) In Chesapeake Bay, Steven G. Morgan Jan 1980

Aspects Of Larval Ecology Of Squilla Empusa (Crustacea, Stomatopoda) In Chesapeake Bay, Steven G. Morgan

OES Faculty Publications

Larvae of Squilla empusa were collected from the plankton and were laboratory-reared in 16 combinations of temperature and salinity to determine their tolerances. Larvae survived longer and molted more frequently when reared at 25%, and 20° or 25° C, which corresponds to the natural conditions of Chesapeake Bay when the larvae were collected.

A 2 year planktonic survey conducted in the lower region of the bay by the Virginia Institute of Marine Sciences was compared with a survey made at the bay mouth in 1976. The seasonal occurrence of Squilla empusa larvae extended from the last week of July until …


Repopulation Of Fishes In Riley Creek, Coles County, Illinois Following Nitrogen Fertilizer Pollution, Kim James Carney Jan 1980

Repopulation Of Fishes In Riley Creek, Coles County, Illinois Following Nitrogen Fertilizer Pollution, Kim James Carney

Masters Theses

The repopulation of stream fishes was studied from 17 May 1979 to 25 October 1979 following a major kill (100% mortality) caused by nitrogen fertilizer pollution in Riley Creek, Coles County, Illinois. The extent of recovery was determined by comparing post-kill collections with pre-kill survey data that was collected on 25 October 1978.

Repopulation began six days after the abatement of the pollution source. It is suggested that the initial source of repopulation was from the nearest undamaged tributary. The first three reinhabitants in order of appearence were: stonerollers (Campostoma anomalum); creek chubs (Semotilus atromaculatus); and …


Nesting And Brood Rearing Ecology Of The Vancouver Canada Goose On Admiralty Island Southeast Of Alaska, Charles S. Lebeda Jan 1980

Nesting And Brood Rearing Ecology Of The Vancouver Canada Goose On Admiralty Island Southeast Of Alaska, Charles S. Lebeda

Electronic Theses and Dissertations

Nesting and brood rearing biology of Vancouver Canada geese (Branta canadensis fulva) was studied in 1978 (preliminary) and from April-August 1979 in Seymour Canal, Admiralty Island, Alaska. Geese used trees for perching during the incubation period (24 April-7 June) and use was significant (P < .0001) for early morning hours. This behavior is considered unique among all Canada goose subspecies. An average of 86.3 search hours were conducted for each of 19 active nests located in 1979. Seven additional nests from previous years were also located. Twenty-two nests were located in forest habitat •. All forest nests were in association with vegetation similar to vegetation described for U.S. Forest Service classification of F4 and F5 (poorly drained) soil types. Mean clutch size was 4.4 ± 1.3 eggs. Mean egg length and width were 86.1 mm± 3.14 and 56.4 mm± 2.76, respectively. Success of all nests hatching at least one egg was 55.6%. Egg hatching success of successful nests was 95.7%. Total hatching success of all eggs was 62.0%. Forest habitat was used extensively for brood rearing. Broods generally avoided large bodies of water. Single family broods were found most often in forest habitat while creches were more common in meadows and intertidal zones. Breeding adults and goslings were comparatively less vocal in the forest. Goslings less than 2 weeks of age used forest habitat extensively and shifted to forest edge and intertidal zones with age. Forest habitats, rather than open water, were used as escape cover by breeding adults and broods. Nesting and brood rearing habitat was similar, thus, nest site selection may be closely tied to requirements for brood rearing habitat. Molting, non-breeding or unsuccessful breeding geese also used forest habitat freely and avoided observers by fleeing into the forest. Use of habitat compared to tide stage was significant (P < .0001) and may be a function of availability. Habitat use compared to daily time periods appeared to reflect feeding activity peaks in early morning and late afternoon. Adult geese primarily used the intertidal zone during pre-incubation; the grassy intertidal zone was used more during incubation and post-incubation. Skunk cabbage (Lysichiton americanum) comprised 23.8% aggregate of foods utilized and appeared to be the most important food during brood rearing. Goslings and molting geese also utilized sea lettuce (Ulva spp.) and blueberry (Yaccinium spp.) berries. Plant matter comprised the bulk of food items.


A Deuterium Nuclear Magnetic Resonance Study Of Chain Disorder In Lamellar Potassium Palmitate: The Effect Of Long And Short Chain Guests, Peter A. Beckmann, E. E. Burnell, M. A. Heldman, K. R. Northey, T. P. Higgs Jan 1980

A Deuterium Nuclear Magnetic Resonance Study Of Chain Disorder In Lamellar Potassium Palmitate: The Effect Of Long And Short Chain Guests, Peter A. Beckmann, E. E. Burnell, M. A. Heldman, K. R. Northey, T. P. Higgs

Physics Faculty Research and Scholarship

The deuterium magnetic resonance spectra of lamellar phases of host perdeuterated potassium palmitate mixed with varying amounts of guest protiated potassium octanoate and behenate and 86.3 mol% D2O are reported. At higher temperatures, the short chain guests give rise to more fluidity and the long chain guests give rise to less fluidity towards the end of the host chain. At low temperatures there are changes in the interaction between the polar head group and the water which depend on sample composition. The transition from the lamellar phase to the low temperature gel phase is investigated and in some …


Principles Of Lake Quality Management, D. B. Porcella Jan 1980

Principles Of Lake Quality Management, D. B. Porcella

Reports

No abstract provided.


Development Of Procedures To Evaluate Salinity Management Strategies In Irrigation Return Flows, V. A. Narasimhan, A. Leon Huber, J. Paul Riley, J. J. Jurinak Jan 1980

Development Of Procedures To Evaluate Salinity Management Strategies In Irrigation Return Flows, V. A. Narasimhan, A. Leon Huber, J. Paul Riley, J. J. Jurinak

Reports

The salinity added irrigation return flows is a major problem in rivers draining agricultural lands throughout the arid regions of the world, and many irrigation water management alternatives have been proposed for reducing downstream salinity problems. The merits of these alternatives, however, can only be judged from reliable information on their actual effects on the salinity in rivers receiving the drainage water and the water withdrawn from the river by downstream users. Hydrosalinity models are widely used to estimate these effects to guide the selection of a policy on management of irrigation return flows. The purpose of this research was …


Alteration Of Microbial Populations In Surface Mine Revegetation And Their Effects On Nitrogen Cycling, Margaret Mary Mccarthy Jan 1980

Alteration Of Microbial Populations In Surface Mine Revegetation And Their Effects On Nitrogen Cycling, Margaret Mary Mccarthy

Reports

Surface mining in the arid west results in soil disruption by alterning structure, water-holding capacity and nutrient availability. Intensive revegetation efforts may end in marginal rehabilitation due to adverse chamical and physical properties of the distrubed soil. Monitoring microbial activitiy and soil chemistry of revegetated and undisturbed areas of a surface mine in Southeastern Montana enabled delineation of major factors participating in soil fertility were determined. In the undisturbed site, the upper few centimeters of the soil profile contained most of the nutrients and the microbial populations. In the revegetated sites, due to mixing of various soil horizons, the concentration …