Physical Sciences and Mathematics Commons^™

Dehydration Tolerance Of Several Populus Deltoides Clones, G. Michael Gebre

School of Natural Resources: Dissertations, Theses, and Student Research

No abstract provided.

Reproductive Biology Of Pinus Sylvestris L.: Seed Yield, Flower Phenology, The Response Of Young Seedlings To Ga 4/7, And Developmental Anatomy, Teresa K. Boes

School of Natural Resources: Dissertations, Theses, and Student Research

No abstract provided.

Species Richness Gradients Of Oak Forest Plants Along The Missouri River In Nebraska And Iowa, Steven B. Rolfsmeier

Nebraska Game and Parks Commission: White Papers, Conference Presentations, and Manuscripts

The upland deciduous forests of the Missouri River valley contain many plants typical of forests to the east of this area, which are assumed to have migrated northward and westward along the river in postglacial times. Previous workers have reported a gradient of decreasing species richness upstream among woody species, which is suggested to be the result of climatic gradients and differential dispersal capabilities of the immigrant species. Floristic work on all vascular species in eight woodland sites along the Nebraska-Iowa border quantifies the presence of similar gradients for herbaceous species, but of differing degrees. These studies also reveal the …

The Nebraska Natural Heritage Program: Two Year Progress Report, Mary Clausen, Mike Fritz, Gerry Steinauer

Nebraska Game and Parks Commission: White Papers, Conference Presentations, and Manuscripts

Since European settlement, human activities have totally eliminated the natural vegetation from approximately 50 percent of Nebraska’s landscape, and of that remaining most has been heavily impacted. As a result, numerous plants and animals have been extirpated from the state and many others are threatened.

The destruction of Nebraska’s natural diversity resulted in both public and private conservation groups recognizing the need for a centralized and accessible biological database for the state’s rare species and natural community types. Toward this end, the Nebraska Natural Heritage Program (NENHP) was established in August, 1987 through a cooperative effort between The Nature Conservancy …

Habitat Use And Diet Analysis Of Breeding Common Barn-Owls In Western Nebraska, Joseph A. Gubanyi M.S.

School of Natural Resources: Dissertations, Theses, and Student Research

I studied barn owl (Tyto alba) breeding biology in western Nebraska 1984-1986. I had greatest success capturing males (56% success) at night using trap doors at nest sites and females (91 % success) using hoop nets at nest sites during the day. Barn owls removed 16 of 23 tail-mounted radios. Eight birds were radio-tracked for 7-14.5 hours. The mean foraging range was 198 ha (32- 299 ha, n = 8) with < 1 % overlap among birds from adjacent nest sites. Field-tested telemetry error was high (mean displacements of radio-locations for 2 birds were 208 and 241 m). I found no relationship between percent cover in foraging habitat and reproductive success. I identified 10,140 prey items from 15 nest sites and found both annual and seasonal variation in barn owl diets. Microtus ochrogaster occurred most frequently (32.7%) and increased in the diet from 17.6 to 27.2 to 43.5% 1984-1986. M. ochrogaster and Perognathus hispidus annual frequencies were …

Plio-Pleistocene Glacial Deposits In Northeastern Nebraska: New Exposures And Interpretations, M. R. Voorhies, R. G. Goodwin

School of Natural Resources: Faculty Publications

A field trip sponsored by the Nebraska Geological Society. Trip Leaders: Dr. M.R. Voorhies, University of Nebraska State Museum. & Dr. R.G. Goodwin, HWS Technologies Inc. Spring 1989

Recent interpretation of oxygen isotopic data for benthic and planktonic foraminifera recovered during ocean drilling programs suggest that world ice volume was greater than the ice volume of 18 thousand years ago (Late Wisconsinan) approximately 2.5 million years ago (Prentice and Matthews, Geology, November, 1988). This agrees well With biostratigraphic and paleoecologic interepretations drawn from sediment cores obtained from the Arctic Ocean Basin. The latter data suggest complete ice cover of the …

Carbon Dioxide, Water Vapor And Sensible Heat Fluxes Over A Tallgrass Prairie, S. B. Verma

School of Natural Resources: Faculty Publications

No abstract provided.

Aerodynamic Resistances To Transfers Of Heat, Mass And Momentum, S. B. Verma

School of Natural Resources: Faculty Publications

No abstract provided.

Assessment Of Squirrel-Caused Power Outages, J. Chris Hamilton, Ron J. Johnson, Ronald M. Case, Michael W. Riley

School of Natural Resources: Faculty Publications

Squirrel-caused power outages in Lincoln and Omaha, Nebraska, were evaluated by examining company power outage reports and by consulting with power company representatives. Reports showed that squirrel-caused outages at pole-mounted transformers were most prevalent during May, June, and October (48% of total) and between 1 and 4 h after sunrise (38%), patterns that coincide with squirrel dispersal or morning activity periods. In Lincoln, 1980 and 1981, squirrels caused 177 outages per year, which was 24% of all outages and 90% of animal-caused outages. Estimated minimum annual costs were $23 364 for repairs, public relations, and lost revenue while meters were …

Geomorphology Of A Pennsylvanian Land Surface: Pedogenesis In The Rock Lake Shale Member, Southeastern Nebraska, Robert Matthew Joeckel

School of Natural Resources: Faculty Publications

No abstract provided.

Geology Of The Pre-Dune Strata, James B. Swinehart, Robert F. Diffendal Jr.

School of Natural Resources: Faculty Publications

Over the last 98 million years, four general geological processes have acted to shape the ancient landscapes buried beneath the Sand Hills. Three of these affected the area directly, either depositing sediments on the land surface or eroding it, while a fourth took place west of Nebraska, but affected the region nonetheless.

Shells of clams, oysters, and numerous other kinds of creatures similar to forms that live today in the seas are preserved as fossils in the chalks, limestones, and shales that form the oldest rocks beneath the Sand Hills that will be described. These deposits indicate to geologists that …

Plio-Pleistocene Glacial Deposits In Northeastern Nebraska: New Exposures And Interpretations, Michael R. Voorhies, R. G. Goodwin

School of Natural Resources: Faculty Publications

Recent interpretation of oxygen isotopic data for benthic and planktonic foraminifera recovered during ocean drilling programs suggest that world ice volume was greater than the ice volume of 18 thousand years ago (Late Wisconsinan) approximately 2.5 million years ago (Prentice and Matthews, Geology, November, 1988). This agrees well With biostratigraphic and paleoecologic interepretations drawn from sediment cores obtained from the Arctic Ocean Basin. The latter data suggest complete ice cover of the basin during the period 2.2-2.4 million years ago (Scott et at., G.S.A. Bulletin, February, 1989).