Earth Sciences Commons^™

Mississippi River Blufflands And Bird Conservation, Eileen M. Kirsch

United States Geological Survey: Staff Publications

The "rubber hits the road" in conservation when the landowning public involved. Researchers and amateur birders know that populations of many species of neotropical migrant birds are declining because of habitat loss and many natural- and human-caused dangers. However, the landowners may not know what neotropical migrants are or that they are in peril. This excellent booklet and enclosed pamphlet are intended to educate landowners along the Mississippi River blufflands in Iowa, Illinois, Wisconsin, and Minnesota about neotropical migrant birds and their plight. Furthermore, it tactfully attempts to inspire concern about neotropical migrants and explains how management can help. While …

Seasonal Distribution Of Migratory Tree Bats (Lasiurus And Lasionycteris) In North America, Paul M. Cryan

United States Geological Survey: Staff Publications

Despite evidence of migration in North American tree bats (genera Lasiurus and Lasionycteris), details regarding seasonal movements in these widely distributed species are few. This study attempted to clarify patterns of seasonal distribution by mapping museum occurrence records by month. Monthly changes in the distribution of records indicate seasonal movements of tree bats. Northward migration during spring by Lasiurus cinereus appears to stem from wintering grounds in California and Mexico. During summer, male L. cinereus is mainly distributed in western North America, whereas females dominate samples from eastern regions. Lasiurus borealis winters in southeastern areas and expands its range …

Eutrophication And Carbon Sources In Chesapeake Bay Over The Last 2700 Yr: Human Impacts In Context, John F. Bratton, Steven M. Colman, Robert R. Seal, Ii

United States Geological Survey: Staff Publications

To compare natural variability and trends in a developed estuary with human-influenced patterns, stable isotope ratios (δ¹³C and δ¹⁵N) were measured in sediments from five piston cores collected in Chesapeake Bay. Mixing of terrestrial and algal carbon sources primarily controls patterns of δ¹³C_org profiles, so this proxy shows changes in estuary productivity and in delivery of terrestrial carbon to the bay. Analyses of δ¹⁵N show periods when oxygen depletion allowed intense denitrification and nutrient recycling to develop in the seasonally stratified water column, in addition to recycling taking place in surficial …

New Record Of The Rare Emballonurid Bat Centronycteris Centralis Thomas, 1912 In Costa Rica, With Notes On Feeding Habits, Neal Woodman

United States Geological Survey: Staff Publications

The shaggy sac-winged bat, Centronycteris centralis (Chiroptera: Emballonuridae), occurs mainly in lowland forests from Veracruz, Mexico, to Peru, although it has been reported from elevations as high at 1450 m in Panama (Simmons and Handley 1998; Hice and Solari 2002). Most captures of the species are of single individuals, and throughout its distribution, this bat is rare and poorly-known (Emmons 1997; Reid 1997; Simmons and Handley 1998). Centronycteris centralis generally has been assumed to be an aerial insectivore, capturing flying insects on the wing (Starrett and Casebeer 1968; Wilson 1973; Timm et al. 1989; LaVal and Rodrı´guez 2002). However, direct …

An Approach For Mapping Large-Area Impervious Surfaces: Synergistic Use Of Landsat-7 Etm+ And High Spatial Resolution Imagery, Limin Yang, Chengquan Huang, Bruce K. Wylie, Michael J. Coan

United States Geological Survey: Staff Publications

A wide range of urban ecosystem studies, including urban climate, land use planning, and resource management, require current and accurate geospatial data of urban impervious surfaces. We developed an approach to quantify urban impervious surfaces as a continuous variable by using multisensor datasets. Subpixel percent impervious surfaces at 30-m resolution were mapped using a regression tree model. The utility, practicality, and affordability of the proposed method for large-area imperviousness mapping were tested over three spatial scales (Sioux Falls, South Dakota, Richmond, Virginia, and the Chesapeake Bay areas of the United States). Average error of predicted versus actual percent impervious surface …

Calibration Of Remotely Sensed, Coarse Resolution Ndvi To Co2 Fluxes In A Sagebrush–Steppe Ecosystem, Bruce K. Wylie, Douglas A. Johnson, Emilio Laca, Nicanor Z. Saliendra, Tagir G. Gilmanov, Bradley C. Reed, Larry L. Tieszen, Bruce B. Worstell

United States Geological Survey: Staff Publications

The net ecosystem exchange (NEE) of carbon flux can be partitioned into gross primary productivity (GPP) and respiration (R). The contribution of remote sensing and modeling holds the potential to predict these components and map them spatially and temporally. This has obvious utility to quantify carbon sink and source relationships and to identify improved land management strategies for optimizing carbon sequestration. The objective of our study was to evaluate prediction of 14-day average daytime CO₂ fluxes ( F_day) and nighttime CO₂ fluxes (R_n) using remote sensing and other data. F_{day …}

Rare-Earth Elements And Nd And Pb Isotopes As Source Indicators For Labrador Sea Clay-Size Sediments During Heinrich Event 2, Larry V. Benson, Don Barber, John T. Andrews, Howard E. Taylor, Paul Lamothe

United States Geological Survey: Staff Publications

Elemental abundances and Nd and Pb isotope ratios were determined on samples from the carbonate-free, clay-size fractions of sediments from intervals above, within, and below Heinrich event 2 (H-2) in core HU87-9 from the Northwest Labrador Sea slope. In HU87-9, rare-earth element (REE) distributions and elemental concentrations within the H-2 event are distinct from those outside this event. ɛ_Nd(0) and ²⁰⁶Pb/²⁰⁴Pb data also indicate different values for sediments deposited within and outside the H-2 event. Comparisons of REE patterns from the H-2 interval with those from bedrock units in Baffin Island, northern Quebec, and Labrador …

Response Of North American Great Basin Lakes To Dansgaard–Oeschger Oscillations, Larry Benson, Steve Lund, Robert M. Negrini, Braddock Linsley, Mladen Zic

United States Geological Survey: Staff Publications

We correlate oscillations in the hydrologic and/or cryologic balances of four Great Basin surface-water systems with Dansgaard– Oeschger (D–O) events 2–12. This correlation is relatively strong at the location of the magnetic signature used to link the lake records, but becomes less well constrained with distance/time from the signature. Comparison of proxy glacial and hydrologic records from Owens and Pyramid lakes indicates that Sierran glacial advances occurred during times of relative dryness. If our hypothesized correlation between the lake-based records and the GISP2 δ¹⁸O record is correct, it suggests that North Atlantic D–O stades …

Late-Holocene Climate And Ecosystem History From Chesapeake Bay Sediment Cores, Usa, Debra A. Willard, Thomas M. Cronin, Stacey Verardo

United States Geological Survey: Staff Publications

Palaeoclimate records from late-Holocene sediments in Chesapeake Bay, the largest estuary in the USA, provide evidence that both decadal to centennial climate variability and European colonization had severe impacts on the watershed and estuary. Using pollen and dinoflagellate cysts as proxies for mid-Atlantic regional precipitation, estuarine salinity and dissolved oxygen (DO) during the last 2300 years, we identified four dry intervals, centred on ad 50 (P1/D1), ad 1000 (P2/D2), ad 1400 (P3) and ad 1600 (P4). Two centennial-scale events, P1/D1 and P2/D2, altered forest composition and led to increased salinity and DO levels in the estuary. Intervals P3 and P4 …

Apparent Break In Earthquake Scaling Due To Path And Site Effects On Deep Borehole Recordings, Satoshi Ide, Gregory C. Beroza, Stephanie G. Prejean, William L. Ellsworth

United States Geological Survey: Staff Publications

We reexamine the scaling of stress drop and apparent stress, rigidity times the ratio between seismically radiated energy to seismic moment, with earthquake size for a set of microearthquakes recorded in a deep borehole in Long Valley, California. In the first set of calculations, we assume a constant Q and solve for the corner frequency and seismic moment. In the second set of calculations, we model the spectral ratio of nearby events to determine the same quantities. We find that the spectral ratio technique, which can account for path and site effects or nonconstant Q, yields higher stress drops, …

Topographically Driven Groundwater Flow And The San Andreas Heat Flow Paradox Revisited, Demian M. Saffer, Barbara A. Bekins, Stephen Hickman

United States Geological Survey: Staff Publications

Evidence for a weak San Andreas Fault includes borehole heat flow measurements that show no evidence for a frictionally generated heat flow anomaly and the inferred orientation of σ₁ nearly perpendicular to the fault trace. Interpretations of the stress orientation data remain controversial, at least in close proximity to the fault, leading some researchers to hypothesize that the San Andreas Fault is, in fact, strong and that its thermal signature may be removed or redistributed by topographically driven groundwater flow in areas of rugged topography, such as typify the San Andreas Fault system. To evaluate this scenario, we use …

Stratigraphy, Geochronology, And Accretionary Terrane Settings Of Two Bronson Hill Arc Sequences, Northern New England, Robert H. Moench, John N. Aleinikoff

United States Geological Survey: Staff Publications

The Ammonoosuc Volcanics, Partridge Formation, and the Oliverian and Highlandcroft Plutonic Suites of the Bronson Hill anticlinorium (BHA) in axial New England are widely accepted as a single Middle to Late Ordovician magmatic arc that was active during closure of Iapetus. Mapping and U–Pb dating indicate, however, that the BHAcontains two volcano-sedimentary-intrusive sequences of probable opposite subduction polarity, here termed the Ammonoosuc and Quimby sequences.

The Ammonoosuc sequence is defined by the Middle Ordovician Ammonoosuc Volcanics near Littleton, NH, the type area, northeast to Milan, NH, and Oquossoc, ME; it also includes black slate of the Partridge Formation (C.bicornis …

Differences In Habitat Use By Blanding’S Turtles, Emydoidea Blandingii, And Painted Turtles, Chysemys Picta, In The Nebraska Sandhills, R. Bruce Bury, David J. Germano

United States Geological Survey: Staff Publications

We sampled a variety of wetlands in the Nebraska sandhills at Valentine National Wildlife Refuge. Significantly more individuals of painted turtles (Chrysemys picta) occurred in lakes and open waters than in marshes or small ponds, and the opposite was true for Blanding’s turtles (Emydoidea blandingii). Besides this marked difference in habitat use, 46% of the captured E. blandingii in pond/marsh habitat were juveniles, but only 31.6% in lakes and open water. Current information suggests that marshes and small ponds are important habitat for juvenile turtles, especially Emydoidea blandingii.

Monitoring Trends In Bat Populations Of The United States And Territories: Status Of The Science And Recommendations For The Future, Thomas J. O'Shea, Michael A. Bogan, Laura E. Ellison

United States Geological Survey: Staff Publications

Populations of bats (Order Chiroptera) are difficult to monitor. However, current recognition of the importance of bats to biodiversity, their ecological and economic value as ecosystem components, and their vulnerability to declines makes monitoring trends in their populations a much-needed cornerstone for their future management. We report findings and recommendations of a recent expert workshop on monitoring trends in bat populations in the United States and territories. We summarize selected case reports presented by others at the workshop, including reviews of methods and ongoing efforts to monitor a wide range of species of bats in a diverse array of situations. …

Public Knowledge And Perceptions Of Black-Tailed Prairie Dogs, Berton Lee Lamb, Kurt Cline

United States Geological Survey: Staff Publications

Black-tailed prairie dogs (Cynomys ludovicianus) historically occupied an 11-state region of the United States. We surveyed 1,900 residents (response rate 56%) of this region to understand citizen knowledge and perceptions about prairie dogs and their management. Those who have direct experience— e.g., those who live very close to prairie dog colonies or know the location of the nearest colony—have higher levels of knowledge. A significantly higher level of knowledge was documented among those who were politically active when compared with the general public. Those who found environmental issues difficult to understand were associated with lower knowledge. People with …

Last Glacial Loess In The Conterminous Usa, E. Arthur Bettis Iii, Daniel R. Muhs, Helen M. Roberts, Ann G. Wintle

United States Geological Survey: Staff Publications

The conterminous United States contains an extensive and generally well-studied record of Last Glacial loess. The loess occurs in diverse physiographic provinces, and under a wide range of climatic and ecological conditions. Both glacial and non-glacial loess sources are present, and many properties of the loess vary systematically with distance from loess sources. United States’ mid-continent Last Glacial loess is probably the thickest in the world, and our calculated mass accumulation rates (MARs) are as high as 17,500 g/m²/yr at the Bignell Hill locality in Nebraska, and many near-source localities have MARs greater than 1500 g/m²/yr. …

Evolution From A Conventional Well Field To A Riverbank-Filtration System, John D. North, Douglas J. Schnoebelen, Shelli Grapp, Roy E. Hesemann

United States Geological Survey: Staff Publications

The City of Cedar Rapids is located in east-central Iowa and has a population of 121,000. The Cedar River alluvial aquifer is the sole source of drinking water for the City. Within the last few years, the Cedar River — which drains a major agricultural watershed — has experienced extended periods of elevated levels of nitrate and herbicides (notably, atrazine and its degradation byproducts) that were above the maximum contaminant level for drinking water. Fortunately, during these extended periods of compromised water quality in the river, RBF enabled the Cedar Rapids Water Department to obtain and treat adequate quantities of …

Ethylenediaminetetraacetic Acid Occurrence And Removal Through Bank Filtration In The Platte River, Nebraska, Jason R. Vogel, Larry B. Barber, Tyler B. Coplen, Ingrid M. Verstraeten, Thomas F. Speth, Jerry Obrist, Win Butler

United States Geological Survey: Staff Publications

The USGS, USEPA, and City of Lincoln Water System (Nebraska) have conducted a study to determine the occurrence and removal of EDTA, NTA, and nonylphenol monoethoxycarboxylate to nonylphenol pentaethoxycarboxylate (NP1EC-NP5EC) in the hydrologic system at the City of Lincoln well field. The objective of the study is to evaluate the occurrence and removal of EDTA, NTA, and total nonylphenolpolyethoxycarboxylate (NPEC) by bank filtration at the City of Lincoln well field. This presentation will discuss removal during two sampling periods — May and August 2002 — based upon surface-water fractions in the collector well calculated using stable isotope ratios of hydrogen …

Intercontinental Migration Of Large Mammalian Carnivores: Earliest Occurrence Of The Old World Beardog Amphicyon (Carnivora, Amphicyonidae) In North America, Robert M. Hunt Jr.

Department of Earth and Atmospheric Sciences: Faculty Publications

North American amphicyonid carnivorans are prominent members of the mid-Cenozoic terrestrial carnivore community during the late Eocene to late Miocene (Duchesnean to Clarendonian). Species range in size from <5 kg to >200 kg. Among the largest amphicyonids are Old and New World species of the genus Amphicyon: A. giganteus in Europe (18–~15? Ma) and Africa, A. ingens in North America (15.9–~14.2 Ma). Amphicyon first appears in the Oligocene of western Europe, surviving there until the late Miocene. Migration to Africa and North America takes place in the early Miocene. The genus occurs in the Arrisdrift fauna (Namibia) of southwest Africa, indicating migration south …

A Daily Soil Temperature Dataset And Soil Temperature Climatology Of The Contiguous United States, Q. Steven Hu, Yongjun Zheng

Department of Earth and Atmospheric Sciences: Faculty Publications

Although affected by atmospheric circulations, variations in soil temperature result primarily from the radiation and sensible and latent heat exchanges at the surface and heat transfer in the soils of different thermal properties. Thus, soil temperature and its variation at various depths are unique parameters that are useful in understanding both the surface energy processes and regional environmental and climatic conditions. Yet, despite the importance, long-term quality data of soil temperatures are not available for the United States. The goal of this study is to fill this data gap and to develop a soil temperature dataset from the historical data …

Nuckolls County Test Hole Logs, Scott E. Summerside

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

Long-Lived Pluvial Episodes During Deposition Of The Navajo Sandstone, David B. Loope, Clinton M. Rowe

Department of Earth and Atmospheric Sciences: Faculty Publications

The Navajo Sandstone of the American Southwest was deposited at approximately 190 Ma in a giant, subtropical dune field near the western margin of Pangea. From this unit, we report thick intervals of dune cross-strata that were churned by insects and trampled by reptiles. Although dunes continued to migrate freely, the distribution of trace fossils shows that plant life in wet interdune areas sustained high levels of animal activity on the dunes for many thousands of years. We interpret this suite of structures as the record of a pluvial episode climatologically similar to the period of “greening” in the Sahara …

Where Are The Women Geoscience Professors?, Mary Anne Holmes, Suzanne O'Connel

Department of Earth and Atmospheric Sciences: Faculty Publications

Compiles an extensive set of data on the status of women in the geosciences, identifying successful strategies for increasing diversity as well as obstacles that hinder efforts. The lessons learned and best practices that arise from this report will help geoscientists continue to increase the gender diversity of their community. Some of these lessons also provide insight into ways to improve the racial and ethnic diversity of the geosciences.

Mylanodon Rosei, A New Metacheiromyid (Mammalia: Palaeanodonta) From The Late Tiffanian (Late Paleocene) Of Northwestern Wyoming, Ross Secord, Philip D. Gingerich, Jonathan I. Bloch

Department of Earth and Atmospheric Sciences: Faculty Publications

Mylanodon rosei is a new genus and species of late Paleocene metacheiromyid palaeanodont from a new late Tiffanian locality, Y2K Quarry, in the Clarks Fork Basin, Wyoming. The type is an adult dentary with P₄ and a molariform double-rooted M₁. This provides the first evidence that molariform teeth were retained in early Metacheiromyidae. A second specimen is a juvenile dentary with a partial P₃ and an unerupted P₄. This is the first juvenile dentition known for a Paleocene metacheiromyid. The new specimens enable determination of dental homologies. Reduction of teeth in early metacheiromyids took …

Lake-Catchment Interactions With Climate In The Low Arctic Of Southern West Greenland, N. John Anderson, Sherilyn C. Fritz, Christopher E. Gibson, Bent Hasholt, Melanie J. Leng

Department of Earth and Atmospheric Sciences: Faculty Publications

Arctic hydrology plays a central role in the earth’s heat balance and ocean circulation (Vörösmarty et al. 2001). Future changes associated with human influence on the climate system are also predicted to cause major changes in the energy and hydrologic mass balance of Arctic catchments. Climate change will likely affect permafrost and snowmelt, which dominate Arctic hydrology and control the chemistry of surface runoff (and hence streams and lakes) as water percolates through the active layer. However, the controls and dynamic impact of snowmelt are poorly understood, because this critical timeframe is often missed by sampling programs. In the Søndre …

The Role Of Climate In Modern Water Planning And Related Decisions: Nebraska Case Study, Donna L. Woudenberg

Open Access Master's Theses (through 2010)

Climate and weather play an integral role in the planning and decision-making processes for those involved in agricultural and natural resource fields. This project was conducted to determine whether climate and weather data are being efficiently and effectively used in these processes.

A survey was mailed to those who work in water-related fields in Nebraska and post-survey interviews were conducted to obtain greater detail. Survey results were analyzed in the following three ways: as a whole; stratified by respondent’s agency; and stratified by the educational background of respondents. It was found that climate and weather data are more likely to …

Analysis Of Integrated Farming Systems In Eastern Nebraska, Lori A. Hoagland

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

Agroecosystems in the U.S. are beset with social, ecological and environmental problems as large industrial farming methods are edging out small family-sized farms and replacing ecological services provided by biodiversity with synthetic inputs and practices. While many of the benefits of smaller diversified or integrated farming systems are well known, farm producers need a concrete model that shows how integration is possible and with what crops. The objective of this study was to investigate some of these supplemental farm activities, and identify and evaluate whether they were compatible given the time and resource constraints of a typical eastern Nebraska farm. …

Provenance Of Sand In Periglacial Sand Wedges And Sheet Sand, Northeastern Nebraska, Usa, William J. Wayne

Department of Earth and Atmospheric Sciences: Faculty Publications

Sand-wedge polygons on upland surfaces beneath thin loess in northeastern Nebraska record existence of permafrost around the margin of the Wisconsinan glacier at its maximum advance. Strong unidirectional wind not only kept the upland surfaces free of snow, allowing frost to penetrate deeply and thermal contraction cracks to develop, but also dessicated the surface material so that frost action and sublimation of pore ice could loosen surface material. The strong NW-SE winds deflated soils from upland surfaces, made ventifacts of the cobbles in the lag that remained and created fields of yardangs oriented NW-SE. Sand derived from the soils and …

Early Deglaciation In The Tropical Andes, G. O. Seltzer, D. T. Rodbell, P. A. Baker, Sherilyn C. Fritz, P. M. Tapia, H. D. Rowe, R. B. Dunbar, Peter U. Clark

Department of Earth and Atmospheric Sciences: Faculty Publications

Analysis of sediment records from lakes located beyond the glacial limit in the Andes has provided, for the first time, an independent assessment of effective moisture ( precipitation minus evaporation) and the timing of the last glaciation (1). Conditions were wet at the LGM and remained so until approximately 15,000 cal yr B.P. (2). However, deglaciation was under way from the LGM between 22,000 and 19,500 cal yr B.P., which reinforces the observation that deglaciation in the tropical Andes was primarily forced by an increase in mean annual temperature during a wet postglacial interval (3, 4).

Development And Implementation Of A Comprehensive Lake And Reservoir Strategy For Nebraska As A Model For Agricultural Dominated Ecosystems, John C. Holz, James W. Merchant, Anatoly A. Gitelson, Sherilyn C. Fritz, Kyle D. Hoagland, Istvan Bogardi, Donald C. Rundquist

Department of Earth and Atmospheric Sciences: Faculty Publications

In agriculturally dominated regions, land use practices have an unusually large impact on water bodies and, therefore, land use may reduce the utility of current ecoregion-based approaches to lake classification by dampening the signals that underlie the ecoregion framework. A team of water quality researchers has been assembled to develop a comprehensive classification scheme for agriculturally dominated ecosystems, using Nebraska as a highly representative model. Three objectives critical to achieving this goal are to establish: (1) a protocol for aggregating water bodies in agricultural ecosystems into classification strata and identifying reference conditions for these classes; (2) the role of remote …