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Ecology Of Iowa Drosophila Ii. Lowland Forest And Sand Prairie, Neil J. Jennings, Robert D. Seager Jan 1989

Ecology Of Iowa Drosophila Ii. Lowland Forest And Sand Prairie, Neil J. Jennings, Robert D. Seager

Journal of the Iowa Academy of Science: JIAS

The seasonal abundances of Drosophila species collected from a lowland forest community and from a sand prairie community in northeastern Iowa are compared. With some important exceptions, the patterns seen in the lowland forest community were similar to what had been observed in a previous collection (Jennings et al. 1985). Fewer species and many fewer individuals were collected from the sand prairie community, although in general the patterns seen were similar to those of the lowland forest community. Strong evidence of microhabitat differentiation was seen in both communities. In contrast to our previous study, none of the seasonal abundance patterns …


A Student Handbook For The Environmental Education / Outdoor School Program In The Middle School, Robert Charles Kenck Jr. Jan 1989

A Student Handbook For The Environmental Education / Outdoor School Program In The Middle School, Robert Charles Kenck Jr.

All Graduate Projects

The purpose of this project was to develop a student handbook that can be used from the onset of an environmental study through the inter-active field study. Students will use the handbook as they begin to study environmental education in the classroom. The handbook will continue to be used as each student attends a three day outdoor school to study firsthand their environment through field activities. The handbook will remain the property of the students.


Residual Influence Of Macronutrient Enrichment On The Aquatic Food Web Of An Okefenokee Swamp Abandoned Bird Rookery, J. Douglas Oliver, Steven A. Schoenberg Jan 1989

Residual Influence Of Macronutrient Enrichment On The Aquatic Food Web Of An Okefenokee Swamp Abandoned Bird Rookery, J. Douglas Oliver, Steven A. Schoenberg

Faculty Publications and Presentations

We present evidence for residual nutrient enrichment of diverse components of a blackwater marsh, by a biotic component of the ecosystem itself. Thousands of nesting white ibis (Eudocimus albus) that foraged over a 20-km radius fertilized a rookery with guano within Okefenokee Swamp. Georgia. USA. One to two yr after the birds abandoned it. this marsh showed continued enrichment effects. Elevated available phosphorus in sediments, as measured by equilibrium phosphate concentration, contributed to enhanced biomass of phytoplankton in the overlying water column. Planktivorous fish were greater in biomass than at reference sites. Experimental phosphorus and nitrogen fertilization of enclosures at …


Foraminiferida Of The Madison Group (Mississippian) Of The Williston Basin, North Dakota, Kurt E. Eylands Jan 1989

Foraminiferida Of The Madison Group (Mississippian) Of The Williston Basin, North Dakota, Kurt E. Eylands

Theses and Dissertations

More than 1500 thin-sections from 73 wells in the North Dakota part of the Williston Basin were searched for their foraminiferal content. This thin-section survey of the Bottineau, Tilston, Frobisher-Alida, and Ratcliffe intervals yielded more than 700 identifiable foraminifers assigned to 26 species.

Most of the Madison foraminifers of the Williston Basin can be placed in one of two superfamilies, the Tournayellacia and the Endothyracea. The Bottineau and Tilston intervals yielded more specimens from the superfamily Tournayellacea while the Frobisher-Alida and Ratcliffe intervals yielded more specimens from the superfamily Endothyracea.

The foraminifers occurred in irregular stratigraphic zones The Bottineau and …


The Vascular Flora Of Pilot Knob State Preserve, William C. Watson Jan 1989

The Vascular Flora Of Pilot Knob State Preserve, William C. Watson

Journal of the Iowa Academy of Science: JIAS

Pilot Knob State Preserve is a 365 acre (147 ha) area lying within the boundaries of Pilot Knob State Park. Located in north central Iowa near the northeast corner of Hancock County, this preserve resides on the eastern morainal system of the Des Moines Lobe left from the Wisconsinan glaciation. The vegetation of the preserve is primarily a deciduous woodland on rolling hills interspersed with wetland habitats in the hollows. Iowa's only floating bog is present in one of these hollows and supports numerous vascular plants uncommon to the state. Two species, Carex cephalantha (Bailey) Bickn. and Drosera rotundifolia L., …


Lake Mixing Dynamics And Water Quality Models, Heinz G. Stefan Jan 1989

Lake Mixing Dynamics And Water Quality Models, Heinz G. Stefan

Journal of the Minnesota Academy of Science

ABSTRACT-To forecast water quality changes or to evaluate the potential success of restoration measures in lakes, it is necessary to formulate "models" which relate lake water quality to the inflows and outflows of materials and energy. Concepts of dynamic deterministic (cause-effect) models and examples are presented. The relationship between internal thermo-hydraulic processes and water quality is stressed. Stratification mixing, and nutrient kinetics are included in these models.


Residence Times Of Minnesota Groundwaters, Scott C. Alexander, E. Calvin Alexander Jr. Jan 1989

Residence Times Of Minnesota Groundwaters, Scott C. Alexander, E. Calvin Alexander Jr.

Journal of the Minnesota Academy of Science

ABSTRACT-Tritium, 14C, and nitrate analyses for eighty groundwater samples from selected Minnesota aquifers indicate a range of residence times from a few days or weeks to tens of thousands of years. The presence of significant nitrate contamination in groundwater is confined to recent or mixed groundwaters. Isotopic studies can yield information that will be useful in the design of effective groundwater protection plans in Minnesota.


Human Impacts To Minnesota Wetlands, Carol A. Johnston Jan 1989

Human Impacts To Minnesota Wetlands, Carol A. Johnston

Journal of the Minnesota Academy of Science

ABSTRACT-Minnesota's 3.6 million ha of wetlands have been impacted by a variety of human activities, including agricultural drainage, urbanization, water control, and nonpoint source pollution. More than half of Minnesota's wetlands have been destroyed since the first European settlers arrived, an average loss of about 35,600 ha/yr. Drainage for agriculture is the major cause of wetland loss in Minnesota, particularly in southern Minnesota and the Red River Valley. In addition to impacting wetlands directly, wetland drainage affects downstream areas by increasing flood flows, and releasing sediment and nutrients. Urban development and highway construction affect a smaller proportion of Minnesota's wetlands, …


The Comprehensive County Water Planning Process In South Central Minnesota, Henry W. Quade, Robert A. Barrett Jan 1989

The Comprehensive County Water Planning Process In South Central Minnesota, Henry W. Quade, Robert A. Barrett

Journal of the Minnesota Academy of Science

ABS~CT-Development of co_unt)_' comprehensi~e water plans is underway in a majority of Minnesota counties as a result of recent leg1slat1on. The planning process requires the fashioning of new relationships and r~les for local and st~te _government, agen':Y personnel, and interdisciplinary technical teams. Early water planning efforts reve~I. s1gmfi~ant problerI:s with the adequacy and applicability of existing water resources da~. Assessment of e1t1Zen attitudes regarding water resource issues was found necessary to link support with policy and develop public education activities. Analysis of water resources data combined with citizen and stat~ agency attitudes has enabled counties in south central Minnesota to …


Nebraska Summary: S078 Ford Versatile 276, Nebraska Tractor Test Lab Jan 1989

Nebraska Summary: S078 Ford Versatile 276, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …


Nebraska Summary: S079 Massey Ferguson 390t, Nebraska Tractor Test Lab Jan 1989

Nebraska Summary: S079 Massey Ferguson 390t, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …


Nebraska Summary: S074 Case-Ih 1896, Nebraska Tractor Test Lab Jan 1989

Nebraska Summary: S074 Case-Ih 1896, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …


The Chemistry Of Sulfonyl Fluorides: Sf5 And/Or So2f Containing Compounds As Precursors To Sulfonic Acids, Robin Joyce Terjeson Jan 1989

The Chemistry Of Sulfonyl Fluorides: Sf5 And/Or So2f Containing Compounds As Precursors To Sulfonic Acids, Robin Joyce Terjeson

Dissertations and Theses

Sulfonyl fluoride systems and their derivatives, RS02F, where R represents hydrocarbon/fluorocarbon moieties continue to be of considerable interest. The incorporation of the sulfonyl fluoride group (S02F) into molecular systems can lead to compounds that are useful as ion-exchange resins, surface active agents, fuel cell electrolytes, and strong sulfonic acids/salts.

Interest in preparing SF5 containing sulfonyl fluorides led to the synthesis of the ᵝ-sultone, SF5CHCF20S02, and its rearranged product. Hydrolysis of the sultone gave SF5CH2S02F which led to the sulfonic acid and salt, SF …


Rottnest Island : A Reference List, Jennifer Browne Jan 1989

Rottnest Island : A Reference List, Jennifer Browne

Research outputs pre 2011

No abstract provided.


The Effect On Farm Profit Of Conserving Stubble To Prevent Wind Erosion, A D. Bathgate Jan 1989

The Effect On Farm Profit Of Conserving Stubble To Prevent Wind Erosion, A D. Bathgate

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

Over-grazing of stubbles is a major cause of winf erosion on WesternAustralian farms. Stubble contributes to the 'roughness' of the paddock; as the roughness is reduced, the risk of winf erosion is increased.

The risk of lupinosis in sheep has previously reduced the likelihood of lupin stubble being over grazed, but the development of Gungurru, a phomopsis-resistent variety of lupin, has increased the potential for over-grazing and hence the probability of wind erosion.

This article describes the economic benefit (or cost) of conserving stubble at the conservation standards.


Organizational Inducements And Social Motives: A Game Theoretic Analysis, Richard G. Davis Jan 1989

Organizational Inducements And Social Motives: A Game Theoretic Analysis, Richard G. Davis

Dissertations and Theses

Game theory was used to analyze compensation systems based on individual and group incentives. Payoff formulas were developed for these incentives assuming different preferences for individual and social outcomes. Two levels of contributions were considered: (1) Defection. The minimum acceptable level of contributions, and (2) Cooperation. A level of discretionary contributions above the minimum. The discretionary contributions associated with cooperation were represented as a cost to the individual.

A classification scheme for uniform n-person games was developed using the approach of Rappaport and Guyer (1966) for 2 x 2 games. This classification scheme defines the natural outcome (cooperation or defection) …


Iowa Geology: The Early Years, Wayne I. Anderson Jan 1989

Iowa Geology: The Early Years, Wayne I. Anderson

Journal of the Iowa Academy of Science: JIAS

In 1975 on the occasion of the first one hundred years of the Iowa Academy of Science, Robert W. Hanson summarized the history of the organization. Additional historical accounts covering many of the science disciplines were published during the centennial year. Although geology was not treated separately in these special articles, the contributions of early geologists were important to the development of science in our state. Consequently, it is appropriate to consider the contributions of early geologists in Iowa in celebration of the one hundredth annual meeting of the Iowa Academy of Science. Included in the present report are the …


Environmental Planning Of Large-Scale Water Projects: The Three Gorges Dam Case, China, Long Li Jan 1989

Environmental Planning Of Large-Scale Water Projects: The Three Gorges Dam Case, China, Long Li

Theses and Dissertations (Comprehensive)

Controversy over the construction of the Three Gorges Dam across the Yangtze River in China is an on-going national issue. Proposals have been advanced by numerous disciplinary research teams to identify the environmental consequences of the project development. However, whether the project will benefit or damage the overall environment still remains in question.

No matter which one of the four storage schemes is going to be put into operation, the human, economic, biological, and physical environmental alterations will have no equal in the our contemporary world and probably even for some time in the future. Above all, flood control, hydro-electricity …


Paleoenvironmental History Of The Middle Ordovician Rugosa Of Eastern North America, Gretchen Hampt Andreasen Jan 1989

Paleoenvironmental History Of The Middle Ordovician Rugosa Of Eastern North America, Gretchen Hampt Andreasen

Honors Papers

Our understanding of the structure and function of biological systems can be increased when viewed in the context of their evolutionary history on a geological time scale. Generally, both paleoecology and ecology have focused on the interrelationships of organisms and their environments in short time frames. For instance, a paleoecologist might study the fossil communities of the Columbus Limestone reefal environment at Marblehead, Ohio, or an ecologist might attempt to characterize the interrelationship of glacier lilies and their pollinators. Both workers may realize that the organisms they study evolved in response to ecological pressures, yet neither, most likely, considers that …


Bacterial Quality Of Private Water Wells In Clark County, Arkansas, S. Conine, D. Cox, K. Mitchell, Clark Kuyper, Jimmy D. Bragg Jan 1989

Bacterial Quality Of Private Water Wells In Clark County, Arkansas, S. Conine, D. Cox, K. Mitchell, Clark Kuyper, Jimmy D. Bragg

Journal of the Arkansas Academy of Science

Most private water wells in Clark County appeared to be contaminated by bacteria, apparently entering the wells from surface water seepage. Eighteen to 24% of the wells investigated were positive for fecal contamination. Deeper wells were less often contaminated. More than one-half of the wells sampled exceeded recommended limits of inorganic chemicals for safe potable water. High concentrations of iron and manganese were most common, exceeding recommended limits in more than 40% of the wells


Morning Increase In Onset Of Ischemic Stroke, John R. Marler, Thomas R. Price, Gregory L. Clark, James E. Muller, Thomas Robertson, Jay P. Mohr, Daniel B. Hìer, Philip A. Wolf, Louis R. Caplan, Mary A. Foulkes Jan 1989

Morning Increase In Onset Of Ischemic Stroke, John R. Marler, Thomas R. Price, Gregory L. Clark, James E. Muller, Thomas Robertson, Jay P. Mohr, Daniel B. Hìer, Philip A. Wolf, Louis R. Caplan, Mary A. Foulkes

Chemistry Faculty Research & Creative Works

The Time of Onset of Ischemic Stroke Was Determined for 1,167 of 1,273 Patients during the Collection of Data by Four Academic Hospital Centers between June 30, 1983, and June 30, 1986. More Strokes Occurred in Awake Patients from 10:00 Am to Noon Than during Any Other 2-Hour Interval. the Incidence of Stroke Onset Declined Steadily during the Remainder of the Day and Early Evening. the Onset of Stroke is Least Likely to Occur in the Late Evening, Before Midnight. © 1989 American Heart Association, Inc.


Multiple-Ionization Collision Dynamics, R. (Ronald) E. Olson, J. Ullrich, H. Schmidt-Böcking Jan 1989

Multiple-Ionization Collision Dynamics, R. (Ronald) E. Olson, J. Ullrich, H. Schmidt-Böcking

Physics Faculty Research & Creative Works

The 1.4-MeV/u U32++Ne collision system is studied in detail in order to elucidate the dynamics of multiple ionization in energetic, heavy-ion atom collisions. Differential cross sections versus recoil-ion charge state, calculated by the n-body classical-trajectory Monte Carlo method, are presented for the and cphi angle dependences of the projectile, recoil ion, and ejected electrons. The calculations show a high degree of ejected-electron asymmetry towards the projectile side of the target nucleus which strongly effects the transverse-momentum balance between the heavy particles. Experimental and calculated cross sections differential in the recoil-ion charge state and transverse momentum are found to …


Lineamenti Geomorfologici Della Costa E Dei Fondali Del Golfo Di Trieste E Considerazioni Sulla Loro Evoluzione Tardo-Quaternaria, Ruggero Marocco Jan 1989

Lineamenti Geomorfologici Della Costa E Dei Fondali Del Golfo Di Trieste E Considerazioni Sulla Loro Evoluzione Tardo-Quaternaria, Ruggero Marocco

International Journal of Speleology

Description of geomorphology of the coasts and the seafloor of the Gulf of Trieste, with paleogeographical discussion on its Late Quaternary evolution.


Nebraska Summary: S075 Case-Ih 5120, Nebraska Tractor Test Lab Jan 1989

Nebraska Summary: S075 Case-Ih 5120, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …


Nebraska Summary: S072 Massey Ferguson 3680, Nebraska Tractor Test Lab Jan 1989

Nebraska Summary: S072 Massey Ferguson 3680, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …


Nebraska Summary: S071 Massey Ferguson 253, Nebraska Tractor Test Lab Jan 1989

Nebraska Summary: S071 Massey Ferguson 253, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …


Chemical Modification Of Skeletal Muscle Sarcoplasmic Reticulum Vesicles: A Study Of Calcium Permeability, Janice F. Stuart Jan 1989

Chemical Modification Of Skeletal Muscle Sarcoplasmic Reticulum Vesicles: A Study Of Calcium Permeability, Janice F. Stuart

Dissertations and Theses

Skeletal muscle contains an internal membrane system called the sarcoplasmic reticulum (SR) whose function is to regulate the Ca2+ concentration of the myoplasm. Ca2+ is transported into the SR from the myoplasm via a Ca2+ dependent ATPase thus lowering the myoplasmic Ca2+ concentration. Ca2+ exits from the SR via a Ca2+ releqse pathway resultingin the increase of myoplasmic Ca2+. Muscles contract when the myoplasmic Ca2+ concentration is > 5 uM and relax when the Ca2+ concentration is lowered below 1 uM. The Ca2+ dependent ATPase has been extensively studied but …


Sedimentary Depositional Cyclicity, Mission Canyon And Charles Formations (Mississippian), Williston Basin, North Dakota, Jean L. Hoff Jan 1989

Sedimentary Depositional Cyclicity, Mission Canyon And Charles Formations (Mississippian), Williston Basin, North Dakota, Jean L. Hoff

Theses and Dissertations

Workers within the Williston Basin have repeatedly reported the presence of sedimentary cyclicity within the carbonate and evaporite succession of the Mississippian Madison Group. Descriptions of cyclicity are diverse and commonly conflict. Previous work has been exclusively qualitative. This study used a group of statistical techniques in a method designed specifically for the objective identification and evaluation of cyclicity in the lithofacies sequence of the Mission Canyon and lower Charles Formations in North Dakota.

Twelve cores were sampled at every visually distinguishable lithologic unit. Forty-six lithologic components were counted in each sample on a presence-absence basis. The phi association coefficient …


Cultivar Evaluation On Low Rainfall Heavy Textured Soils., Bradley Nutt Jan 1989

Cultivar Evaluation On Low Rainfall Heavy Textured Soils., Bradley Nutt

Experimental Summaries - Plant Research

a. Trial 88GE34

Cultivar evaluation in machine sown plots.
Location: NMRS

The higher seed yield of Serena compared to the other cultivars resulted in better early forage .production as well a legume dominated pasture.

b. Trial 88TS 63 and 88TS 65

Wheat yields following pastures.
Location: 88TS63 - Perenjori and 88TS65 - Three Springs.

There was no response to nitrogen in either biological yield or grain yield of wheat sown over volunteer based pasture at the Three Springs site. All pasture treatments resulted in similar wheat yields except for Sava because of poor control of the snail medic under the …


Loss Of Biological Diversity: A Global Crisis Requiring International Solutions: A Report To The National Science Board, Craig Call Black, Perry L. Adkisson, Gardner Mallard Brown, Rita Rossi Colwell, Charles E. Hess, James B. Holderman, K. June Lindstedt-Siva, William A. Nierenberg, Peter Hamilton Raven, Theodore M. Smith, Edward O. Wilson, W. Franklin Harris Jan 1989

Loss Of Biological Diversity: A Global Crisis Requiring International Solutions: A Report To The National Science Board, Craig Call Black, Perry L. Adkisson, Gardner Mallard Brown, Rita Rossi Colwell, Charles E. Hess, James B. Holderman, K. June Lindstedt-Siva, William A. Nierenberg, Peter Hamilton Raven, Theodore M. Smith, Edward O. Wilson, W. Franklin Harris

Harold W. Manter Laboratory of Parasitology: Library Materials

Executive Summary

Biological diversity refers to the variety and variability among living organisms and the ecological complexes in which they occur. Diversity can be defined as the number of different items and their relative frequency. For biological diversity, these items are organized at many levels, ranging from complete ecosystems to the chemical structures that are the molecular basis of heredity. Thus, the term encompasses different ecosystems, species, genes, and their relative abundance (OTA, 1987).

There is an ongoing, unprecedented loss of the variety as well as absolute numbers of organisms-from the smallest microorganism to the largest and most spectacular of …