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Full-Text Articles in Physical Sciences and Mathematics

The Biological Significance And Utility Of Feeding By Dermestes Maculatus, Braymond Adams Dec 2018

The Biological Significance And Utility Of Feeding By Dermestes Maculatus, Braymond Adams

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

With their efficient feeding habits and tolerance to very low moisture and humidity, beetles in the Family Dermestidae are especially adapted to variable environments and habitats. Dermestid cultures have been in use since 1922 in cleaning tissue and flesh from bones, and proven benefit in multiple fields, including zoology, ornithology, and forensics. Dermestid feeding behaviors when coupled with known life stage and insect succession information aids in providing significant entomological evidence. However, the feeding activities of insects, like those of vertebrate scavengers and predators, change remains and may leave artifacts that can be sometimes be difficult to assign to a …


Hydrogeologic Framework Studies Of Portions Of The Niobrara River, Douglas R. Hallum, Steven S. Sibray, Leslie M. Howard Dec 2018

Hydrogeologic Framework Studies Of Portions Of The Niobrara River, Douglas R. Hallum, Steven S. Sibray, Leslie M. Howard

Conservation and Survey Division

The Nebraska Department of Natural Resources (NeDNR) and Upper Niobrara-White Natural Resources District (UNWNRD) expressed interest in improving understanding and their ability to effectively manage water resources in and around a particular reach of the Niobrara River. Aquifer-thickness contours mapped by the Conservation and Survey Division (CSD) indicate that the principle aquifer has zero thickness in this area. Additionally, the statewide geologic bedrock map produced by CSD shows non-aquifer strata of the White River Group along the same reach, and this setting is consistent with the designation of an “aquifer absent area,” as in the present document. Water-management policy development …


New Insights Into Carboniferous Cyclothems. The Fourth Biennial Field Conference Of The American Association Of Petroleum Geologists (Aapg) Midcontinent Section Fourth Biennial Field Conference Abstracts And Guidebook, Robert Matthew Joeckel, Christopher R. Fielding Oct 2018

New Insights Into Carboniferous Cyclothems. The Fourth Biennial Field Conference Of The American Association Of Petroleum Geologists (Aapg) Midcontinent Section Fourth Biennial Field Conference Abstracts And Guidebook, Robert Matthew Joeckel, Christopher R. Fielding

Conservation and Survey Division

The term “cyclothem” was coined by Wanless & Weller (1932) to describe repetitive stratigraphic successions of Carboniferous age in Illinois. Nonetheless, comparable rhythmicity had been identified in Carboniferous rocks both in the central and eastern USA, and in Europe during the preceding century. Cyclothems were found to comprise repetitive vertical successions of sandstones, heterolithic (thinly interbedded) sandstones and mudrocks, mudrocks, limestones, and coals, in many cases with pedogenic overprinting of these lithologies. As usage of the term “cyclothem” increased, so did the diversity of successions to which the term was applied, to the point where many geologists advocated abandonment of …


County-Wide Assessment Of Irrigation Expansion On Air Temperature, Humidity And Evapotranspiration Rates In Nebraska, 1979-2015, Jozsef Szilagyi Sep 2018

County-Wide Assessment Of Irrigation Expansion On Air Temperature, Humidity And Evapotranspiration Rates In Nebraska, 1979-2015, Jozsef Szilagyi

Conservation and Survey Division

Total irrigated land area has been expanding in Nebraska over the last 40 years, propelling the state into a leading position within the US in terms of irrigated acreages. Typically, those counties which display the largest degree of irrigation development had a significant portion of their land area already irrigated in 1978. Large-scale irrigation in Nebraska affects its atmospheric environment. During the typical irrigation season of May to August, counties with the largest rate of irrigation expansion have cooled by about 0.2 – 0.3 °F per decade in the summer months of June, July and August, while counties with the …


A Quantitative Analysis Of Calcareous Nannofossils Across A Late Oligocene Paleolatitude Transect Of The North Atlantic Ocean, William Barrett Clark Aug 2018

A Quantitative Analysis Of Calcareous Nannofossils Across A Late Oligocene Paleolatitude Transect Of The North Atlantic Ocean, William Barrett Clark

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

Samples from ODP Sites 926, 628, 563, U1406, 647, and 918, were analyzed quantitatively across a paleolatitude transect of the North Atlantic Ocean to determine the paleolatitudinal distribution of calcareous nannofossils in the Late Oligocene and the effects of that distribution on biostratigraphic resolution. Detrended Correspondence Analysis (DCA), a Temperature index (TI), and the Shannon Diversity Index (H), were used to examine the paleoenvironmental gradients which exerted the most control over the distribution of species and their abundances. The temperature index correlates significantly to the first axis of the DCA, suggesting that thermal controls were the most important factor in …


A Taxon-Free, Multi-Proxy Model For Making Paleoecological Interpretations Of Neogene North American Faunas, Devra G. Hock Jun 2018

A Taxon-Free, Multi-Proxy Model For Making Paleoecological Interpretations Of Neogene North American Faunas, Devra G. Hock

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

Proxies used for interpreting the paleoecology of extinct vertebrate communities are usually based on modern ecosystems, with many developed from Old World ecosystems. However, because no model is completely taxon-free and phylogenetic influences cannot be entirely discounted, these proxies may not be appropriate for paleoecological interpretations of North American ecosystems. Additionally, many proxies based on modern vertebrate communities exclude small-bodied mammals. Here I explore several new paleoecological models based on the frequency of mammalian traits within three ecological categories: locomotion, diet, and body mass. Since these models are intended for interpreting paleoenvironments occupied by Neogene North American mammals, the data …


The Carnivores Of Agate Fossil Beds National Monument: Miocene Dens And Waterhole In The Valley Of A Dryland Paleoriver, Robert M. Hunt Jr., Robert Skolnick, Joshua Kaufman Jun 2018

The Carnivores Of Agate Fossil Beds National Monument: Miocene Dens And Waterhole In The Valley Of A Dryland Paleoriver, Robert M. Hunt Jr., Robert Skolnick, Joshua Kaufman

Zea E-Books Collection

In 1981 University of Nebraska paleontologists came upon an unexpected concentration of carnivore dens at Agate Fossil Beds National Monument in northwest Nebraska. The discovery of bones of Miocene beardogs, mustelids, and canids in their burrows was unparalleled and marked an exceptional event in the fossil record. Survey and excavation (1981–1990) established that six species of carnivores had, over time, occupied the dens with traces of their prey: juvenile and adult oreodonts, camels, and a neonatal rhinoceros. At least nine individuals of the wolf-like beardog Daphoenodon superbus, the most common carnivore, were identified from remains of young, mature, and aged …


Results Of Test-Hole Drilling For Observation Well Planning In The Lower Loup Natural Resources District, Spring 2017, Douglas R. Hallum P.G., Sue Olafsen Lackey, Steven S. Sibray May 2018

Results Of Test-Hole Drilling For Observation Well Planning In The Lower Loup Natural Resources District, Spring 2017, Douglas R. Hallum P.G., Sue Olafsen Lackey, Steven S. Sibray

Conservation and Survey Division

The High Plains Aquifer underlies much of Nebraska. It is the primary source of groundwater within the Lower Loup Natural Resources District (LLNRD) of central Nebraska. Water derived from the aquifer is an important natural resource for the area and supplies water for recreation, wildlife and agriculture, as well as domestic, municipal, and industrial uses. Falling spring water levels measured in existing observation and irrigation wells have raised concerns about possible changes in water availability, groundwater-surface water relationships and water quality in the area, prompting the LLNRD to propose test holes and the collection of additional groundwater data in the …


Body Size Downgrading Of Mammals Over The Late Quaternary, Felisa A. Smith, Rosemary E. Elliott Smith, S. Kathleen Lyons, Jonathan L. Payne Apr 2018

Body Size Downgrading Of Mammals Over The Late Quaternary, Felisa A. Smith, Rosemary E. Elliott Smith, S. Kathleen Lyons, Jonathan L. Payne

School of Biological Sciences: Faculty Publications

Since the late Pleistocene, large-bodied mammals have been extirpated from much of Earth. Although all habitable continents once harbored giant mammals, the few remaining species are largely confined to Africa. This decline is coincident with the global expansion of hominins over the late Quaternary. Here, we quantify mammalian extinction selectivity, continental body size distributions, and taxonomic diversity over five time periods spanning the past 125,000 years and stretching approximately 200 years into the future. We demonstrate that size-selective extinction was already under way in the oldest interval and occurred on all continents, within all trophic modes, and across all time …


Fossils On The Floor In The Nebraska State Capitol: A Coloring And Activities Book, Robert F. Diffendal Jr. Mar 2018

Fossils On The Floor In The Nebraska State Capitol: A Coloring And Activities Book, Robert F. Diffendal Jr.

Conservation and Survey Division

The Nebraska State Capitol is a wonderful place. This building is home to great treasures of art owned by the people of Nebraska. The floor of the Capitol Rotunda has beautiful works of art. Maybe you have seen this art. Small pieces of two kinds of rocks make pictures of people, their tools, the natural resources they used, and pictures of fossil animals and plants. These kinds of pictures are called mosaics [moe ZAY icks]. The animals and plants follow one another in a curved ribbon around the floor. In that ribbon of pictures are many kinds of fossil animals …


The Groundwater Atlas Of Red Willow County, Nebraska, Dana Divine, Duane Eversoll, Leslie M. Howard Jan 2018

The Groundwater Atlas Of Red Willow County, Nebraska, Dana Divine, Duane Eversoll, Leslie M. Howard

Conservation and Survey Division

The purpose of this groundwater atlas is to synthesize a wealth of hydrogeologic data for Red Willow County that has not been published in readily accessible formats previously. Many of the maps presented here are based on geologic information from registered wells and test holes that is publically available on-line, which becomes more valuable when compiled, analyzed, and discussed as a whole.

In Red Willow County, the aquifers are alluvial sand and gravel in the river and stream valleys and the High Plains aquifer beneath the uplands. The High Plains aquifer in Red Willow County consists primarily of the Ogallala …


Review Of The Ends Of The World: Volcanic Apocalypses, Lethal Oceans, And Our Quest To Understand Earth's Past Mass Extinctions, By Peter Brannen, Robert F. Diffendal Jr. Jan 2018

Review Of The Ends Of The World: Volcanic Apocalypses, Lethal Oceans, And Our Quest To Understand Earth's Past Mass Extinctions, By Peter Brannen, Robert F. Diffendal Jr.

Robert F. Diffendal, Jr., Publications

In his new best-selling book, Peter Brannen, award-winning science writer, takes you on a fascinating trip through the run-up to the end of the Cretaceous extinction event and the K-Pg (Cretaceous/Paleogene) boundary, formerly called the K-T (Cretaceous/Tertiary) boundary.

Brannen interviewed many scientists who studied these events and went on field trips with them to major Cretaceous sites and to those where earlier and later extinction events happened. He presents clear explanations of what is known and not known about all of these events in a largely error-free book. Brannen details the other four big extinction events in geologic history: the …


Combining Hydraulic Head Analysis With Airborne Electromagnetics To Detect And Map Impermeable Aquifer Boundaries, Jesse T. Korus Jan 2018

Combining Hydraulic Head Analysis With Airborne Electromagnetics To Detect And Map Impermeable Aquifer Boundaries, Jesse T. Korus

Conservation and Survey Division

Impermeable aquifer boundaries affect the flow of groundwater, transport of contaminants, and the drawdown of water levels in response to pumping. Hydraulic methods can detect the presence of such boundaries, but these methods are not suited for mapping complex, 3D geological bodies. Airborne electromagnetic (AEM) methods produce 3D geophysical images of the subsurface at depths relevant to most groundwater investigations. Interpreting a geophysical model requires supporting information, and hydraulic heads offer the most direct means of assessing the hydrostratigraphic function of interpreted geological units. This paper presents three examples of combined hydraulic and AEM analysis of impermeable boundaries in glacial …