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Short-Term Sediment Accumulation Rates Determined From Eocene Alluvial Paleosols, Mary J. Kraus, Thomas M. Bown Jan 1993

Short-Term Sediment Accumulation Rates Determined From Eocene Alluvial Paleosols, Mary J. Kraus, Thomas M. Bown

United States Geological Survey: Staff Publications

A new method uses alluvial paleosols to calculate sediment accumulation rates for thin (25 m) stratigraphic intervals and allows the reliable interpolation of ages for stratigraphic levels within a thick stratigraphic interval bounded by established dates. Sediment accumulation rates calculated for a 650 m composite section in the Eocene Willwood Formation of Wyoming span time intervals ranging from only 0.05 to 0.25 may. Important sedimentologic changes coincide with changes in accumulation rate and indicate close and direct relations between the history of basin subsidence and depositional patterns.


Water-Quality Assessment Of The Central Nebraska Basins: Summary Of Data For Recent Conditions Through 1990, Ronald B. Zelt, P. R. Jordan Jan 1993

Water-Quality Assessment Of The Central Nebraska Basins: Summary Of Data For Recent Conditions Through 1990, Ronald B. Zelt, P. R. Jordan

United States Geological Survey: Publications

Among the first activities undertaken in each National Water-Quality Assessment (NAWQA) investigation are the compilation, screening, and statistical summary of available data concerning recent water-quality conditions in the study unit. The water-quality conditions of interest in addressing the objectives of the NAWQA program are those that are representative of the general water quality of a given stream reach or area of an aquifer. This report (1) identifies which existing water-quality data are suitable for characterizing general conditions in a nationally consistent manner and (2) describes, to the extent possible, recent, general water-quality conditions in the Central Nebraska Basins. The study …


Nebraska Butterflies, Stephen M. Spomer Jan 1993

Nebraska Butterflies, Stephen M. Spomer

University of Nebraska State Museum: Staff and Affiliates, Publications

Nebraska is a crossroads of butterfly diversity. Many species reach their distributional limits in Nebraska. The 100th meridian, which runs through central Nebraska, appears to be a good distributional limit for many species. In short, eastern Nebraska contains butterflies similar or identical to those found in most of the eastern United States, central Nebraska has both eastern and western butterflies, and western Nebraska has a butterfly fauna more like the Rocky Mountains or Black Hills. Over 200 species of butterflies have been recorded in Nebraska, which is a higher number than most of our neighboring states. Some of our butterflies …


Vertebrates For Biological Control Of Insects In Agroforestry Systems, James R. Brandle Jan 1993

Vertebrates For Biological Control Of Insects In Agroforestry Systems, James R. Brandle

School of Natural Resources: Faculty Publications

No abstract provided.


Iowa Academy Of Science Directory, 1993-94, Iowa Academy Of Science Jan 1993

Iowa Academy Of Science Directory, 1993-94, Iowa Academy Of Science

Iowa Academy of Science Documents

Contents:

Board of Directors ... 5
Program Directors ... 6
Editors ... 6
Committees ... 8
Sections ... 22
Awards of Merit ... 28
Excellence in Science Teaching Awards ... 29
Past Presidents ... 30
Membership Roster ... 31


1993 File Geodatabase Containing Aerial Photos, Pete Reehling, Richard Mckenzie, City Of Tampa Department Of Sanitary Sewers Bay Study Group Jan 1993

1993 File Geodatabase Containing Aerial Photos, Pete Reehling, Richard Mckenzie, City Of Tampa Department Of Sanitary Sewers Bay Study Group

Images

The Bay Study Group was created by the City of Tampa in 1976 to monitor the effects of pollution abatement that occurred in Hillsborough Bay when the city’s wastewater treatment plant was upgraded from primary to advanced treatment in 1979. The Bay Study Group documented a remarkable restoration of water quality parameters and biological indicators in Hillsborough Bay from the mid 1980s until 2009, when it was disbanded. This zip Geodatabase file contains the aerial photos for the year 1993.


13.4.8. Options For Water-Level Control In Developed Wetlands, J. R. Kelley Jr., M. K. Laubhan, F. A. Reid, J. S. Wortham, L. H. Fredrickson Jan 1993

13.4.8. Options For Water-Level Control In Developed Wetlands, J. R. Kelley Jr., M. K. Laubhan, F. A. Reid, J. S. Wortham, L. H. Fredrickson

Waterfowl Management Handbook

Wetland habitats in the United States currently are lost at a rate of 260,000 acres /year (105,218 ha/year). Consequently, water birds concentrate in fewer and smaller areas. Such concentrations may deplete food supplies and influence behavior, physiology, and survival. Continued losses increase the importance of sound management of the remaining wetlands because water birds depend on them.

Human activities modified the natural hydrology of most remaining wetlands in the conterminous United States, and such hydrologic alterations frequently reduce wetland productivity. The restoration of original wetland functions and productivity often requires the development of water distribution and discharge systems to emulate …


Fall 1993, Nsu Oceanographic Center Jan 1993

Fall 1993, Nsu Oceanographic Center

Currents

No abstract provided.


Spring 1993, Nsu Oceanographic Center Jan 1993

Spring 1993, Nsu Oceanographic Center

Currents

No abstract provided.


Summer 1993, Nsu Oceanographic Center Jan 1993

Summer 1993, Nsu Oceanographic Center

Currents

No abstract provided.


Program Review 1993: Self Study Report Department Of Biometry Jan 1993

Program Review 1993: Self Study Report Department Of Biometry

Department of Statistics: Reports and Administrative Materials

The CSRS review team applauds the statistical expertise of the Biometry Department which began as the statistical Laboratory in 1957 and culminated with the current academic Department of Biometry. This enhancement has been highlighted by a significant increase in the number of faculty and staff, the initiation of a Master of Science program, and the provision of graduate assistant stipends. With the presence of seven faculty, the imminent increase from seven to fifteen graduate students, the establishment of statistical consulting with numerous IANR faculty, and the diverse research and teaching expertise of the faculty, the department is poised to provide …


13.2.11. Increasing Waterfowl Nesting Success On Islands And Peninsulas, John T. Lokemoen Jan 1993

13.2.11. Increasing Waterfowl Nesting Success On Islands And Peninsulas, John T. Lokemoen

Waterfowl Management Handbook

Waterfowl that nest in uplands in the prairie pothole region have had low recruitment rates in recent decades, primarily because of predation. The loss of breeding waterfowl and their progeny has generated interest in management techniques that safeguard incubating hens and their eggs. Developing islands and peninsulas for nesting waterfowl has potential because these sites are naturally attractive to breeding ducks and geese. In fact, dense nesting colonies of ducks developed on some islands when successful females and a portion of their female progeny returned in subsequent years.

Managers have successfully duplicated the beneficial attributes of islands by developing various …


When Will A Genetic Algorithm Outperform Hill-Climbing?, Melanie Mitchell, John H. Holland Jan 1993

When Will A Genetic Algorithm Outperform Hill-Climbing?, Melanie Mitchell, John H. Holland

Computer Science Faculty Publications and Presentations

In this paper we review some previously published experimental results in which a simple hillclimbing algorithm-Random Mutation Hill-Climbing (RMHC)-significantly outperforms a genetic algorithm on a simple "Royal Road" function. vVe present an analysis of RMHC followed by an analysis of an "idealized" genetic algorithm (IGA) that is in turn significantly faster than RMHC. We isolate the features of the IGA that allow for this speedup, and discuss how these features can be incorporated into a real GA and a fitness landscape, making the GA better approximate the IGA. We use these features to design a modified version of the previously …


Revisiting The Edge Of Chaos: Evolving Cellular Automata To Perform Computations, Melanie Mitchell, Peter T. Hraber, James P. Crutchfield Jan 1993

Revisiting The Edge Of Chaos: Evolving Cellular Automata To Perform Computations, Melanie Mitchell, Peter T. Hraber, James P. Crutchfield

Computer Science Faculty Publications and Presentations

No abstract provided.


A Study Of The Growth Of Daughter Cladodes In The Species Of Cactus Opunita Ficus-Indica, Lin Moore Jan 1993

A Study Of The Growth Of Daughter Cladodes In The Species Of Cactus Opunita Ficus-Indica, Lin Moore

Whittier Scholars Program

Opunita ficus-indica is an example of a Prickly Pear cactus. Indigenous to Mexico, it is cultivated world wide for its edible flesh and fruit. It’s water use efficiency is high. The plant establishes where there is deep soil and a little subirrigation, such as washes in valleys or at the mouths of small canyons. The fleshy stem pads are called cladodes. The basal cladode is the lowermost cladode, and daughter cladodes grow from it. Daughter cladodes grow in orientations that maximize PPFD. Favorably oriented cladodes produce more daughter cladodes than those that are orientated unfavorably. Since O. ficus- indica is …


1993 File Geodatabase Containing Photo Point Locations, Aerial Photos, And Flight Maps, City Of Tampa Department Of Sanitary Sewers Bay Study Group, Pete Reehling, Richard Mckenzie Jan 1993

1993 File Geodatabase Containing Photo Point Locations, Aerial Photos, And Flight Maps, City Of Tampa Department Of Sanitary Sewers Bay Study Group, Pete Reehling, Richard Mckenzie

Data Sets

The Bay Study Group was created by the City of Tampa in 1976 to monitor the effects of pollution abatement that occurred in Hillsborough Bay when the city’s wastewater treatment plant was upgraded from primary to advanced treatment in 1979. The Bay Study Group documented a remarkable restoration of water quality parameters and biological indicators in Hillsborough Bay from the mid 1980s until 2009, when it was disbanded. This zip Geodatabase file contains the photo point locations, aerial photos, and flight maps for the year 1993.


Organic Geochemistry Of Permian Organic-Rich Sediments From The Sudetes Area, Sw Poland, Shareen R. Yawanarajah, Michael A. Kruge, Maria Mastalerz, Wojciech Sliwinski Jan 1993

Organic Geochemistry Of Permian Organic-Rich Sediments From The Sudetes Area, Sw Poland, Shareen R. Yawanarajah, Michael A. Kruge, Maria Mastalerz, Wojciech Sliwinski

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Lacustrine and marine sediments from the Permian rift-basins of southwestern Poland were analysed using GC-MS and petrographic techniques. High Pr/Ph ratios, gamma- and beta-carotanes and gammacerane in the lacustrine sediments indicate deposition under elevated water salinities. The primary organic matter is represented by bacterial and algal lipids with variable terrestrial input. Marine algal lipids with minor bacterial and cyanobacterial lipids are the primary source of organic matter in the marine sediments. Extended hopanes, n-alkanes with even-odd predominance and low Ts/Tm ratios are consistent with deposition in a closed, evaporitic basin with substantial carbonate sedimentation.


1993-1994 Nova College James M. Farquhar Center For Undergraduate Studies Catalog, Nova Southeastern University Jan 1993

1993-1994 Nova College James M. Farquhar Center For Undergraduate Studies Catalog, Nova Southeastern University

Undergraduate Programs Course Catalogs

No abstract provided.


Effects Of Predator Odors On Feeding In The Mountain Beaver (Aplodontia Rufa), Gisela Epple, J. Russell Mason, Dale L. Nolte, Dan L. Campbell Jan 1993

Effects Of Predator Odors On Feeding In The Mountain Beaver (Aplodontia Rufa), Gisela Epple, J. Russell Mason, Dale L. Nolte, Dan L. Campbell

United States Department of Agriculture Wildlife Services: Staff Publications

Consumption of food by Aplodontia rufa from bowls scented with control odors, secretion from anal glands of minks (Mustela vison), or urine from minks, bobcats (Felis rufus), and coyotes (Canis latrans) was studied. In two-choice control tests, subjects indiscriminately consumed apple from unscented bowls and from bowls scented with urine from an unfamiliar herbivore (Cavia porcellus), or with butyric acid. During two-choice tests offering apple from bowls scented with secretion from anal glands of minks and from bowls scented with butyric acid, significantly less apple was consumed from bowls containing mink scent. …


Seasonal Water Regimes And Leaf Litter Processing In A Wetland On The Swan Coastal Plain, Darren Ryder Jan 1993

Seasonal Water Regimes And Leaf Litter Processing In A Wetland On The Swan Coastal Plain, Darren Ryder

Theses : Honours

The effect of seasonal or permanent inundation on the processing of leaf litter from two competing emergent macrophytes Baumea articulata and Typha orientalis was examined at Lake Jandabup, a seasonal wetland on the Swan Coastal Plain. The loss of organic matter from leaf packs was used to quantify leaf litter processing. The contributions made by microorganisms and macroinvertebrates in processing were also assessed. Leaf packs exposed to seasonal inundation (defined as those areas exposed to alternate wetting and drying) had significantly higher losses of organic matter after six months than those permanently inundated for the same period. The presence of …


Microzooplankton Distributions In The Irish Sea, Carol A. Burkart Jan 1993

Microzooplankton Distributions In The Irish Sea, Carol A. Burkart

HCNSO Student Theses and Dissertations

The purpose of this study was to determine the distributions and abundances of microzooplankton across a front in the Irish Sea, and to test the hypothesis that the structure which develops within the microzooplankton community is the result of the interactions within the communities.

Eight sites were sampled on May 1-2, 1989 along a transect from Liverpool Bay, England to Dundalk Bay, Ireland. The transect crossed both the Liverpool Bay and western Irish Sea fronts; sites were positioned with respect to water type (e.g., coastal, thermally mixed, thermally stratified) . Five sites were sampled by double Longhurst-Hardy Plankton Recorder (LHPR) …


The Potential Effects Of Climate Change On Summer Season Dairy Cattle Milk Production And Reproduction, Peggy L. Klinedinst, Donald A. Wilhite, G. Leroy Hahn, Kenneth G. Hubbard Jan 1993

The Potential Effects Of Climate Change On Summer Season Dairy Cattle Milk Production And Reproduction, Peggy L. Klinedinst, Donald A. Wilhite, G. Leroy Hahn, Kenneth G. Hubbard

National Drought Mitigation Center: Faculty Publications

The potential direct effects of possible global warming on summer season dairy production and re-production were evaluated for the United States and Europe. Algorithms used for milk production and conception rate were previously developed and validated. Three widely known global circulation models (GISS, GFDL, and UKMO) were used to represent possible scenarios of future climate. Milk production and conception rate declines were highest under the UKMO model scenario and lowest under the GISS model scenario. Predicted declines for the GCM scenarios are generally higher than either “l year in 10” probability-based declines or declines based on the abnormally hot summer …


13.3.14. Detrital Accumulation And Processing In Wetlands, Patrick A. Magee Jan 1993

13.3.14. Detrital Accumulation And Processing In Wetlands, Patrick A. Magee

Waterfowl Management Handbook

Wetlands are among the most productive ecosystems on earth (Fig. 1) and are often characterized by lush growths of hydrophytes. However, direct consumption of wetland plants by animals is relatively low, and, therefore, much of the biomass and energy assimilated by hydrophytes becomes detritus or senesced plant litter. Nutrients released by detritus into the water and soil are assimilated by microorganisms, algae, plants, and small aquatic animals. Through this process, energy is transferred from detritus to other biotic components of a wetland. Plant litter ultimately decomposes.

Litter processing is regulated by environmental factors, microbial activity, the presence and abundance of …


13.1.11. Life History Traits And Habitat Needs Of The Redhead, Christine Mitchell Custer Jan 1993

13.1.11. Life History Traits And Habitat Needs Of The Redhead, Christine Mitchell Custer

Waterfowl Management Handbook

Redheads are one of five common diving duck species in North America. They are in the same taxonomic group as the pochards or bay ducks and are most similar in appearance and behavior to the canvasback. Smaller body size, late breeding, wintering in southern areas, and tolerance to salt in winter and in breeding areas differentiate the redhead from the canvasback and suggest an evolutionary origin in the arid areas of the West. Parasitism of other waterfowl nests is more pronounced in redheads than in other North American waterfowl. These and other aspects of the biology of the redhead are …


13.1.15. Life History And Habitat Needs Of The Black Brant, Dirk V. Derksen, David H. Ward Jan 1993

13.1.15. Life History And Habitat Needs Of The Black Brant, Dirk V. Derksen, David H. Ward

Waterfowl Management Handbook

The black brant is a sea goose that depends on coastal habitats from high arctic nesting sites in Canada, Alaska, and Russia to wintering areas in the Pacific coastal states, the Baja California peninsula, and mainland Mexico estuaries. Population estimates are based on aerial surveys in Mexico, California, Oregon, and Washington during mid-winter. Despite much annual variability in estimates, a plot of the counts from 1964 to 1992 reveals a significant downward trend in the winter populations (Fig. 1). Three of four major colonies on the Yukon&#;Kuskokwim (Y&#;K) delta declined an average of 60% during the first half of the …


Center For Sustainable Agricultural Systems Newsletter, January/February 1993 Jan 1993

Center For Sustainable Agricultural Systems Newsletter, January/February 1993

Center for Sustainable Agricultural Systems: Newsletter (1993–2000)

Defining Production Systems in Nebraska

Nebraska Environmental Trust Fund

Sustainable Ag Grants for Producers

National Sustainable Ag Coordinating Council

Federal Conservation Policy Is Changing

FAO Examines Education Programs on Environmental Sustainability

Research on Reducing Environmental Impacts of Livestock

In the Seminar Spotlight

Electronic Communication Is In


Long-Term, Seasonal, And Event-Driven Sediment Movement On East Beach, San Salvador Island, Bahamas, Andrew L. Brill, H. Allen Curran, William T. Fox Jan 1993

Long-Term, Seasonal, And Event-Driven Sediment Movement On East Beach, San Salvador Island, Bahamas, Andrew L. Brill, H. Allen Curran, William T. Fox

Geosciences: Faculty Publications

East Beach is a modern, medium-energy shoreline located on the northeast coast of San Salvador Island, Bahamas. Stake and horizon profiles were made at 9 sites along a 1-km section of the beach in June, 1990, and every six months thereafter through January,1992. These observations appear to confirm that East Beach is a prograding shoreline, building onto the eastern shelf of the island. Seasonally corrected volume calculations indicate that between June, 1990 and January, 1992 approximately 14,000 m3 of new sand per kilometer were added to the East Beach system, with most of the sand likely derived from the …


Editorial Board & Iowa Academy Of Science Officers And Directors Jan 1993

Editorial Board & Iowa Academy Of Science Officers And Directors

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Evaluation Of Passive Integrated Transponders As A Marking Technique For Turkey Poults, Dewaine H. Jackson, William H. Bunger Jan 1993

Evaluation Of Passive Integrated Transponders As A Marking Technique For Turkey Poults, Dewaine H. Jackson, William H. Bunger

Journal of the Iowa Academy of Science: JIAS

Injectable, passive integrated transponders (PITs) were evaluated as a marking technique for newly hatched wild turkey (Meleagris gallopavo Linnaeus) poults. Seven of 12, 3-day-old domestic turkey poults received a PIT implant and a wing tag. A control group of five poults received only a wing tag. Two subcutaneous implant sites were evaluated, along the right side of the neck and in the area between the right inner thigh and breast. One of7 PITs failed or was expelled during the first week. Four scanning errors, in which the PIT was present yet not detected during the initial scanning attempt, occurred in …


Range Expansion Of The Great-Tailed Grackle In The 1900s, James J. Dinsmore, Stephen J. Dinsmore Jan 1993

Range Expansion Of The Great-Tailed Grackle In The 1900s, James J. Dinsmore, Stephen J. Dinsmore

Journal of the Iowa Academy of Science: JIAS

In 1900, the range of the Great-tailed Grackle extended north of the Mexican border only into Texas. Since then, it has expanded its range greatly. It now nests in 14 states and has strayed to an additional eight states and three Canadian provinces. Much of this expansion has occurred since 1960. Great-tails often stray far from their normal range, especially in spring. Most of these strays are single individuals. In states where they have nested, breeding birds typically reach the state a few years after the first reports of the species. Great-tailed Grackles do well in a variety of human …