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Karst Geology And Cave Fauna Of Austria: A Concise Review, Erhard Christian, Christoph Spötl Jan 2010

Karst Geology And Cave Fauna Of Austria: A Concise Review, Erhard Christian, Christoph Spötl

International Journal of Speleology

The state of cave research in Austria is outlined from the geological and zoological perspective. Geologic sections include the setting of karst regions, tectonic and palaeoclimatic control on karst, modern cave environments, and karst hydrology. A chapter on the development of Austrian biospeleology in the 20th century is followed by a survey of terrestrial underground habitats, biogeographic remarks, and an annotated selection of subterranean invertebrates.


Glacier (?) National Park, Judy Mcilrath Jan 2010

Glacier (?) National Park, Judy Mcilrath

School of Geosciences Faculty and Staff Publications

In this Spreadsheets Across the Curriculum activity, students examine data pertaining to the disappearing glaciers in Glacier National Park. After calculating percentage change of the number of glaciers from 1850 (150) to 1968 (50) and 2009 (26), they move on to the main glacier-monitoring content of the module--area vs. time data for the Grinnell Glacier, one of 26 glaciers that remain in the park. Using a second-order polynomial (quadratic function) fitted to the data, they extrapolate to estimate when there will be no Grinnell Glacier remaining (illustrating the relevance of the question mark in the title of the module). Introductory …


Late Devonian Spermatophyte Diversity And Paleoecology At Red Hill, North-Central Pennsylvania, U.S.A., Walter L. Cressler Iii, Cyrille Prestianni, Ben A. Lepage Jan 2010

Late Devonian Spermatophyte Diversity And Paleoecology At Red Hill, North-Central Pennsylvania, U.S.A., Walter L. Cressler Iii, Cyrille Prestianni, Ben A. Lepage

Earth & Space Sciences Faculty Publications

No abstract provided.


Terrestrialization In The Late Devonian: A Palaeoecological Overview Of The Red Hill Site, Pennsylvania, Usa, Walter L. Cressler Iii, Edward B. Daeschler, Rudy Slingerland, Daniel A. Peterson Jan 2010

Terrestrialization In The Late Devonian: A Palaeoecological Overview Of The Red Hill Site, Pennsylvania, Usa, Walter L. Cressler Iii, Edward B. Daeschler, Rudy Slingerland, Daniel A. Peterson

Earth & Space Sciences Faculty Publications

No abstract provided.


Glacial Deposits, Vol. 38, 2009-2010, Department Of Geography-Geology Jan 2010

Glacial Deposits, Vol. 38, 2009-2010, Department Of Geography-Geology

Glacial Deposits

Newsletter of the Department of Geography-Geology


Rare Earth Elements As An Investigative Tool Into The Source, Age, And Ecology Of Late Miocene To Late Pleistocene Fossils From The Tunica Hills, Louisiana, Lindsey Theresa Yann Jan 2010

Rare Earth Elements As An Investigative Tool Into The Source, Age, And Ecology Of Late Miocene To Late Pleistocene Fossils From The Tunica Hills, Louisiana, Lindsey Theresa Yann

LSU Master's Theses

Rare earth elements were investigated for their potential to determine provenance and depositional environments of vertebrate fossils found as float in creeks of the Tunica Hills region of Louisiana. Elemental analyses are used to test the hypotheses that fossils span multiple time periods, from late Miocene to late Pleistocene, and that elemental profiles can distinguish terrestrial depositional settings from possible estuarine deposits. In addition, the animals present were then used to test the hypothesis that Tunica Hills had late Pleistocene environmental conditions much like the modern Great Lakes region. This study is important because it provides new insight on the …


Social-Ecological Resilience Of A Nuosu Community-Linked Watershed, Southwest Sichuan, China, Lauren S. Urgenson, R. Keala Hagmann, Amanda C. Henck Schmidt, Stevan Harrell, Thomas M. Hinckley, Sara Jo Shepler, Barbara L. Grub, Philip M. Chi Jan 2010

Social-Ecological Resilience Of A Nuosu Community-Linked Watershed, Southwest Sichuan, China, Lauren S. Urgenson, R. Keala Hagmann, Amanda C. Henck Schmidt, Stevan Harrell, Thomas M. Hinckley, Sara Jo Shepler, Barbara L. Grub, Philip M. Chi

Faculty & Staff Scholarship

Farmers of the Nuosu Yi ethnic group in the Upper Baiwu watershed report reductions in the availability of local forest resources. A team of interdisciplinary scientists worked in partnership with this community to assess the type and extent of social-ecological change in the watershed and to identify key drivers of those changes. Here, we combine a framework for institutional analysis with resilience concepts to assess system dynamics and interactions among resource users, resources, and institutions over the past century. The current state of this system reflects a legacy of past responses to institutional disturbances initiated at the larger, national system …


Using Inoceramid Bivalve Taphonomy As A Paleoenvironmental Indicator Across The Cenomanian/Turonian Horizon At The Pueblo, Colorado Gssp, Jacob Frederick Grosskopf Jan 2010

Using Inoceramid Bivalve Taphonomy As A Paleoenvironmental Indicator Across The Cenomanian/Turonian Horizon At The Pueblo, Colorado Gssp, Jacob Frederick Grosskopf

LSU Master's Theses

Recent paleoenvironmental and geochemical studies indicate that benthic conditions during Oceanic Anoxic Event II (OAE II) (93.5 Mya) in the Cretaceous Interior Seaway (CIS) were dysoxic rather than anoxic. In this thesis, dysoxic benthic conditions were tested for by observing patterns in taphonomic alteration of the calcite portions of inoceramid bivalve shells during and after OAE II. Inoceramid valves were extracted from beds that spanned OAE II at the Cenomanian/Turonian Global Boundary Stratotype Section and Point (GSSP) in Pueblo, Colorado: beds 62 (Hartland Shale), 72 (Bridge Creek Limestone), and 115 (Bridge Creek Limestone). Degree of alteration was tallied using categorical …


Taphonomy And Sedimentology Of Two Miocene Vertebrate Fossil Sites On Fort Polk, Louisiana, Julie Lynn Hill Jan 2010

Taphonomy And Sedimentology Of Two Miocene Vertebrate Fossil Sites On Fort Polk, Louisiana, Julie Lynn Hill

LSU Master's Theses

The discovery of a terrestrial mammalian fauna in the Miocene deposits on Fort Polk, Louisiana, fills a geographic gap in the Gulf Coast paleontological framework, but the provenance of the fossils, nature of the depositional environments, and relationships between the sites is still debated. This is especially true for the TVOR site cluster. TVOR SE has a mixture of marine and terrestrial vertebrates in association with a partly dissolved, in situ bed of articulated oyster shells, which stands in contrast to the fully terrestrial and freshwater assemblage at TVOR, and the indeterminate site TVOR S. Although limited outcrop may bias …


Bioturbation, Habitat Partitioning, And Tiering In Tropical Intertidal Callianassid Mounds: An Example From The Bahamas, H. Allen Curran Jan 2010

Bioturbation, Habitat Partitioning, And Tiering In Tropical Intertidal Callianassid Mounds: An Example From The Bahamas, H. Allen Curran

Geosciences: Faculty Publications

Abstract from 2010 Workshop on Crustacean Bioturbation — Fossil and Recent held in Lepe, Spain.

Editors: Jordi M. deGibert, Fernando Muñiz, Eduardo Mayoral, Zain Belaústegui


Paleolimnological Reconstruction Of Hydrologic Change In The Slave River And Great Slave Lake During The Past Millennium, Matthew Ennis Jan 2010

Paleolimnological Reconstruction Of Hydrologic Change In The Slave River And Great Slave Lake During The Past Millennium, Matthew Ennis

Theses and Dissertations (Comprehensive)

The Slave River Delta (SRD), NWT, represents a pivotal node in the upper Mackenzie Basin watershed and is a productive northern wetland landscape with a rich natural and cultural heritage. Concerns over environmental consequences of natural and anthropogenic-driven decline in river discharge as well as climate variability have prompted hydroecological sstudies to improve understanding of how this ecosystem functions over time and space. However, long-term natural hydrological variability of the Slave River system is not well documented and needs to be further developed. In order to provide a temperal context for understanding and evaluating the impacts of climate variability and …


Cretaceous/Paleogene Boundary Biostratigraphy And Palynofacies Of The Alo-1 Well, Southeastern Nigeria, Janet Diane Raymer Jan 2010

Cretaceous/Paleogene Boundary Biostratigraphy And Palynofacies Of The Alo-1 Well, Southeastern Nigeria, Janet Diane Raymer

Masters Theses

"The Cretaceous/Paleogene boundary (K/Pg) has been studied in great detail because of the fascination most people have with the extinction of the dinosaurs. The response of the vegetation to this extinction event has been studied in detail in mid to high latitudes, but little is known about what happened in the tropics. Sixty-seven samples from the Nsukka and Imo formations in the Alo-1 well in the Anambra Basin, southeastern Nigeria have been studied for their palynological contents. The aims of the study was to use spores, pollen and dispersed organic matter components to interpret biostratigraphy, and evaluate depositional conditions across …


Phosphorus For High Rainfall Pastures, Mike Bolland, Bill Russell, David Weaver Jan 2010

Phosphorus For High Rainfall Pastures, Mike Bolland, Bill Russell, David Weaver

Bulletins 4000 -

Soil testing for phosphorus provides a reliable indication of when the level of phosphorus in a soil is likely to be adequate for pasture production in the next growing season. It is a waste of money to apply phosphorus fertiliser when soil testing indicates none is required, or to acidified soils, or to undergrazed pastures, or to pastures dominated by poorly productive species.

Legumes have higher phosphorus requirement than grasses.

Critical soil test phosphorus values do not change when nitrogen fertiliser is applied.


Implementing Deep Drainage To Reduce Salinity In The Date Creek Catchment, South West Western Australia, Derk Bakker, John P. Collins, Justin Hardy Jan 2010

Implementing Deep Drainage To Reduce Salinity In The Date Creek Catchment, South West Western Australia, Derk Bakker, John P. Collins, Justin Hardy

Resource management technical reports

No abstract provided.


Combined Effects Of Heat Waves And Droughts On Avian Communities Across The Conterminous United States, Thomas P. Albright, Anna M. Pidgeon, Chadwick D. Rittenhouse, Murray K. Clayton, Brian D. Wardlow, Curtis H. Flather, Patrick D. Culbert, Volker C. Radeloff Jan 2010

Combined Effects Of Heat Waves And Droughts On Avian Communities Across The Conterminous United States, Thomas P. Albright, Anna M. Pidgeon, Chadwick D. Rittenhouse, Murray K. Clayton, Brian D. Wardlow, Curtis H. Flather, Patrick D. Culbert, Volker C. Radeloff

National Drought Mitigation Center: Faculty Publications

Increasing surface temperatures and climatic variability associated with global climate change are expected to produce more frequent and intense heat waves and droughts in many parts of the world. Our goal was to elucidate the fundamental, but poorly understood, effects of these extreme weather events on avian communities across the conterminous United States. Specifically, we explored: (1) the effects of timing and duration of heat and drought events, (2) the effects of jointly occurring drought and heat waves relative to these events occurring in isolation, and (3) how effects vary among functional groups related to nest location and migratory habit, …


A New Small-Bodied Species Of Palaeonictis (Creodonta, Oxyaenidae) From The Paleocene-Eocene Thermal Maximum, Stephen G. B. Chester, Jonathan I. Bloch, Ross Secord, Doug M. Boyer Jan 2010

A New Small-Bodied Species Of Palaeonictis (Creodonta, Oxyaenidae) From The Paleocene-Eocene Thermal Maximum, Stephen G. B. Chester, Jonathan I. Bloch, Ross Secord, Doug M. Boyer

Department of Earth and Atmospheric Sciences: Faculty Publications

Oxyaenid creodonts are extinct carnivorous mammals known from the Paleogene of North America, Europe, and Asia. The genus Palaeonictis is represented by three species that together span the late Paleocene to early Eocene of North America, and at least one species from the early Eocene of Europe. Previously, only a single trigonid of Palaeonictis was known from the interval encompassing the Paleocene-Eocene Thermal Maximum (PETM) in North America. We describe Palaeonictis wingi sp. nov. from the PETM in the Cabin Fork drainage, southeastern Bighorn Basin, Wyoming, based on associated right and left dentaries with P2-M2. Palaeonictis …


Blending Rudists With Technology; Non-Destructive Examination Of The Internal And External Structures Of Rudists Using High Quality Scanning And Digital Imagery, Ann Molineux, Robert W. Scott, Jessie Maisano, Richard Ketcham, Louis Zachos Jan 2010

Blending Rudists With Technology; Non-Destructive Examination Of The Internal And External Structures Of Rudists Using High Quality Scanning And Digital Imagery, Ann Molineux, Robert W. Scott, Jessie Maisano, Richard Ketcham, Louis Zachos

Turkish Journal of Earth Sciences

Certain formations within the Cretaceous of Texas include zones of silicified rudists. Such diagenetic alteration, combined with the timing of alteration, has preserved many structural features of the rudist suitable for computed tomography (CT scanning). The excellent density differences between those skeletal structures (silica) and the internal sediment (calcitic mud) or later crystallization (calcite), fulfill a fundamental requirement for such analysis. The Jackson School of Geosciences at The University of Texas provides access to a high resolution computed tomography scanning system. This equipment, not identical to medical scanners, provides higher resolution and sophisticated software to analyze the imagery. Several rudist …


Mercury Speciation In Temperate Tree Foliage, Melissa Danielle Tabatchnick Jan 2010

Mercury Speciation In Temperate Tree Foliage, Melissa Danielle Tabatchnick

Browse all Theses and Dissertations

Cycling of mercury (Hg) and monomethylmercury (MMHg) in forest ecosystems can affect exposures of terrestrial and aquatic wildlife within the watershed. Litterfall has been posited to be a major source of MMHg and total Hg to the forest floor; however, the origin of MMHg associated with tree foliage is largely unknown. I tested the hypothesis that leaf MMHg would be controlled by root uptake and thereby proportional to levels in soil. Fresh leaves and associated soil samples were sampled from nine tree species (deciduous and coniferous) at 30 locations spanning a 1145 km2 area in southwest Ohio, a region presumed …


Inferring Lake Depth Using Diatom Assemblages In The Shallow, Seasonally Variable Lakes Of The Nebraska Sand Hills (Usa): Calibration, Validation, And Application Of A 69-Lake Training Set, Avery L. C. Shinneman, Danuta M. Bennett, Sherilyn C. Fritz, Jens Schmieder, Daniel R. Engstrom, Aris Efting, John Holz Jan 2010

Inferring Lake Depth Using Diatom Assemblages In The Shallow, Seasonally Variable Lakes Of The Nebraska Sand Hills (Usa): Calibration, Validation, And Application Of A 69-Lake Training Set, Avery L. C. Shinneman, Danuta M. Bennett, Sherilyn C. Fritz, Jens Schmieder, Daniel R. Engstrom, Aris Efting, John Holz

Department of Earth and Atmospheric Sciences: Faculty Publications

The Nebraska Sand Hills are a distinctive eco-region in the semi-arid Great Plains of the western United States. The water table underlying the Sand Hills is part of the High Plains/ Ogallala aquifer, an important water resource for the central Great Plains. Lake levels are affected directly by fluctuations in the water table, which is recharged primarily by local precipitation and responds quickly to climatically induced changes in regional water balance. Instrumental records are available for only 50–100 years, and paleolimnological data provide important insights into the extremes and variability in moisture balance over longer time scales. A set of …


Stratigraphic Signature Of The Late Palaeozoic Ice Age In The Parmeener Supergroup Of Tasmania, Se Australia, And Inter-Regional Comparisons, Christopher R. Fielding, Tracy D. Frank, John L. Isbell, Lindsey C. Henry, Eugene W. Domack Jan 2010

Stratigraphic Signature Of The Late Palaeozoic Ice Age In The Parmeener Supergroup Of Tasmania, Se Australia, And Inter-Regional Comparisons, Christopher R. Fielding, Tracy D. Frank, John L. Isbell, Lindsey C. Henry, Eugene W. Domack

Department of Earth and Atmospheric Sciences: Faculty Publications

Recent research in eastern Australia has established that rather than being a single, long-lived epoch, the late Palaeozoic Ice Age comprised a series of glacial intervals each 1–8 million years in duration, separated by non-glacial intervals of comparable duration. In order to test whether the glacial events recognized in New South Wales and Queensland have broader extent, we conducted a reappraisal of the Parmeener Supergroup of Tasmania, southeast Australia. A facies analysis of the Pennsylvanian to Permian section was carried out, allowing rationalization of the succession into four recurrent facies associations: a) glacigenic facies association, restricted to the basal Pennsylvanian/earliest …


Tetrapod Fauna Of The Lowermost Usili Formation (Songea Group, Ruhuhu Basin) Of Southern Tanzania, With A New Burnetiid Record, Christian A. Sidor, Kenneth D. Angielczyk, D. Marie Weide, Roger M. H. Smith, Sterling J. Nesbitt, Linda A. Tsuji Jan 2010

Tetrapod Fauna Of The Lowermost Usili Formation (Songea Group, Ruhuhu Basin) Of Southern Tanzania, With A New Burnetiid Record, Christian A. Sidor, Kenneth D. Angielczyk, D. Marie Weide, Roger M. H. Smith, Sterling J. Nesbitt, Linda A. Tsuji

Department of Earth and Atmospheric Sciences: Faculty Publications

Vertebrate fossils from the Ruhuhu Basin of southern Tanzania have been known for over 75 years, but the details of their stratigraphic distribution remain imperfectly understood. Recent fieldwork in the Upper Permian Usili Formation (Songea Group) has led to the discovery of a tetrapod assemblage in a conglomeratic unit at its base. The fossils are concentrated in matrix-supported intraformational clay pebble conglomerates interpreted as mass flow deposits in wide, shallow channels in the distal reaches of an alluvial fan. Included in this new collection are fossils representing the first record of a burnetiid therapsid from Tanzania. The anatomy of the …


Effects Of Irrigated Agroecosystems: 2. Quality Of Soil Water And Groundwater In The Southern High Plains, Texas, B. R. Scanlon, J. B. Gates, R. C. Reedy, W. A. Jackson, J. P. Bordovsky Jan 2010

Effects Of Irrigated Agroecosystems: 2. Quality Of Soil Water And Groundwater In The Southern High Plains, Texas, B. R. Scanlon, J. B. Gates, R. C. Reedy, W. A. Jackson, J. P. Bordovsky

Department of Earth and Atmospheric Sciences: Faculty Publications

Trade‐offs between water‐resource depletion and salinization need to be understood when promoting water‐conservative irrigation practices. This companion paper assesses impacts of groundwater‐fed irrigation on soil water and groundwater quality using data from the southern High Plains (SHP). Unsaturated zone soil samples from 13 boreholes beneath irrigated agroecosystems were analyzed for water‐extractable anions. Salt accumulation in soils varies with irrigation water quality, which ranges from low salinity in the north (median Cl: 21 mg/L) to higher salinity in the south (median Cl: 180 mg/L). Large Cl bulges under irrigated agroecosystems in the south are similar to those under natural ecosystems, but …


The Ties That Bind: Soil Surveyor William Edgar Tharp And Oceanographic Cartographer Marie Tharp, Edward R. Landa Jan 2010

The Ties That Bind: Soil Surveyor William Edgar Tharp And Oceanographic Cartographer Marie Tharp, Edward R. Landa

United States Geological Survey: Staff Publications

The link between soil science and geology is personified in the American father and daughter: soil surveyor William Edgar Tharp (1870–1959) and oceanographic cartographer Marie Tharp (1920–2006). From 1904 to 1935, W.E. Tharp mapped soils in 14 states for the US Department of Agriculture, and campaigned during the late 1920s–early 1930s to raise awareness of the high rates of soil erosion from croplands. The lifestyle of the federal soil surveyor in the United States during the early 20th century involved frequent household moves, and it played a formative role in Marie Tharp’s childhood. Her path to a career in geology …


Evidence For Recent Population Bottlenecks In Northern Spotted Owls (Strix Occidentalis Caurina), W. Chris Funk, Eric D. Forsman, Matthew Johnson, Thomas D. Mullins, Susan M. Haig Jan 2010

Evidence For Recent Population Bottlenecks In Northern Spotted Owls (Strix Occidentalis Caurina), W. Chris Funk, Eric D. Forsman, Matthew Johnson, Thomas D. Mullins, Susan M. Haig

United States Geological Survey: Staff Publications

The northern spotted owl (Strix occidentalis caurina) is one of the most controversial threatened subspecies ever listed under the US Endangered Species Act. Despite protection of its remaining forest habitat, recent field studies show continued declines of northern spotted owls. One potential threat to northern spotted owls which has not yet been shown is loss of genetic variation from population bottlenecks. Bottlenecks can increase the probability of mating among related individuals, potentially causing inbreeding depression, and can decrease adaptive potential. Here we report evidence for recent bottlenecks in northern spotted owls using a large genetic dataset (352 individuals …


Barcoding Bushmeat: Molecular Identification Of Central African And South American Harvested Vertebrates, Mitchell J. Eaton, Greta J. Meyers, Sergios-Orestis Kolokotronis, Matthew S. Leslie, Andrew P. Martin, George Amato Jan 2010

Barcoding Bushmeat: Molecular Identification Of Central African And South American Harvested Vertebrates, Mitchell J. Eaton, Greta J. Meyers, Sergios-Orestis Kolokotronis, Matthew S. Leslie, Andrew P. Martin, George Amato

United States Geological Survey: Staff Publications

The creation and use of a globally available database of DNA sequences from a standardized gene region has been proposed as a tool for species identification, assessing genetic diversity and monitoring the legal and illegal trade in wildlife species. Here, we contribute to the Barcode of Life Data System and test whether a short region of the mitochondrial cytochrome c oxidase subunit 1 (COX1) gene would reliably distinguish among a suite of commonly hunted African and South American mammal and reptile species. We used universal primers to generate reference barcode sequences of 645 bp for 23 species from five vertebrate …


Barcoding Bushmeat: Molecular Identification Of Central African And South American Harvested Vertebrates, Mitchell J. Eaton, Greta L. Meyers, Sergios-Orestis Kolokotronis, Matthew S. Leslie, Andrew P. Martin, George Amato Jan 2010

Barcoding Bushmeat: Molecular Identification Of Central African And South American Harvested Vertebrates, Mitchell J. Eaton, Greta L. Meyers, Sergios-Orestis Kolokotronis, Matthew S. Leslie, Andrew P. Martin, George Amato

United States Geological Survey: Staff Publications

The creation and use of a globally available database of DNA sequences from a standardized gene region has been proposed as a tool for species identification, assessing genetic diversity and monitoring the legal and illegal trade in wildlife species. Here, we contribute to the Barcode of Life Data System and test whether a short region of the mitochondrial cytochrome c oxidase subunit 1 (COX1) gene would reliably distinguish among a suite of commonly hunted African and South American mammal and reptile species. We used universal primers to generate reference barcode sequences of 645 bp for 23 species from five vertebrate …


Ancient Dna Analyses Exclude Humans As The Driving Force Behind Late Pleistocene Musk Ox (Ovibos Moschatus) Population Dynamics, Paula F. Campos, Eske Willerslev, Andrei Sher, Ludovic Orlando, Erik Axelsson, Alexei Tikhonov, Kim Aaris-Sorensen, Alex D. Greenwood, Ralf-Dietrich Kahlke, Pavel Kosintsev Jan 2010

Ancient Dna Analyses Exclude Humans As The Driving Force Behind Late Pleistocene Musk Ox (Ovibos Moschatus) Population Dynamics, Paula F. Campos, Eske Willerslev, Andrei Sher, Ludovic Orlando, Erik Axelsson, Alexei Tikhonov, Kim Aaris-Sorensen, Alex D. Greenwood, Ralf-Dietrich Kahlke, Pavel Kosintsev

Biological Sciences Faculty Publications

The causes of the late Pleistocene megafaunal extinctions are poorly understood. Different lines of evidence point to climate change, the arrival of humans, or a combination of these events as the trigger. Although many species went extinct, others, such as caribou and bison, survived to the present. The musk ox has an intermediate story: relatively abundant during the Pleistocene, it is now restricted to Greenland and the Arctic Archipelago. In this study, we use ancient DNA sequences, temporally unbiased summary statistics, and Bayesian analytical techniques to infer musk ox population dynamics throughout the late Pleistocene and Holocene. Our results reveal …


To The Ice: George Bird Grinnell's 1887 Ascent Of Grinnell Glacier, Richard Vaughan Jan 2010

To The Ice: George Bird Grinnell's 1887 Ascent Of Grinnell Glacier, Richard Vaughan

Articles by Maurer Faculty

This article discusses a climbing expedition undertaken by U.S. conservationist George Bird Grinnell to ascend what would come to be known as Grinnell Glacier in Montana. Grinnell’s efforts to establish Glacier National Park are detailed. Grinnell’s previously unpublished descriptions of the glacier and its surrounding area are analyzed by the author.


La Yeguada Volcanic Complex, Western Panama : An Assessment Of The Geologic Hazards Using New 40Ar/39Ar Ages, Karinne L. Knutsen Jan 2010

La Yeguada Volcanic Complex, Western Panama : An Assessment Of The Geologic Hazards Using New 40Ar/39Ar Ages, Karinne L. Knutsen

Dissertations, Master's Theses and Master's Reports - Open

La Yeguada volcanic complex is one of three Quaternary volcanic centers in Panama, and is located on the southern slope of the Cordillera Central mountain range in western Panama, province of Veraguas. To assess potential geologic hazards, this study focused on the main dome complex near the village of La Laguna and also examined a cinder cone 10 km to the northwest next to the village of Media Luna. Based on newly obtained 40Ar/39Ar ages, the most recent eruption occurred approximately 32 000 years ago at the Media Luna cinder cone, while the youngest dated eruption at …


Effects Of Livestock Antibiotics On Nitrification, Denitrification, And Microbial Community Compositon In Soils Along A Topographic Gradient, Sagarika Banerjee Jan 2010

Effects Of Livestock Antibiotics On Nitrification, Denitrification, And Microbial Community Compositon In Soils Along A Topographic Gradient, Sagarika Banerjee

University of Kentucky Master's Theses

Several types of antibiotics (roxarsone, virginiamycin, and bacitracin) are widely included in poultry feed to improve animal growth yields. Most of the antibiotics are excreted in manure which is subsequently applied to soils. One concern with this practice is that antibiotics may affect several microbially-mediated nutrient cycling reactions in soils that influence crop productivity and water quality. The main objectives of this study were to determine the effects of livestock antibiotics on nitrification, denitrification, and microbial community composition in soils along a topographic gradient. These objectives were addressed in a series of lab experiments by monitoring changes in inorganic N …