Earth Sciences Commons^™

Caves And Karst Of West-Central Florida, Lee J. Florea, David A. Budd, Robert B. Brinkman

Earth, Environmental, and Atmospheric Sciences Faculty Publications

No abstract provided.

Setting Targets For Resource Condition In Lake Towerrinning Catchment, G Paul Raper, Leon Vanwyk

Resource management technical reports

No abstract provided.

Bringing Us Together : Presentations From The Natural Resource Management Division Meeting, May 2008, Georgina Wilson, Don Bennett, Richard J. George, Sandra Van Vreeswyk, Rebecca Heath, Jamie Bowyer, T M. Lacey, Dennis Van Gool, Peter J. Tille, John P. Collins, Justin L.M Hardy, Derk Bakker, Arjen Ryder, Bindi Isbister, Bill H. Verboom, Luke Bayley, Karen Roberts, Kaz Johnson, Richard Glover

Resource management technical reports

No abstract provided.

The Pecos River Hypogene Speleogenetic Province: A Basin-Scale Karst Paradigm For Eastern New Mexico And West Texas, Usa, Kevin W. Stafford, Alexander Klimchouk, Lewis Land, Marcus O. Gary

Faculty Publications

Since the mid-Tertiary, lateral migration and entrenchment of the Pecos River Valley in eastern New Mexico and west Texas, USA, has significantly influenced regional groundwater flow paths, providing a focus for ascending flow in multi-storey artesian systems and a powerful potentiometric driving force for hypogene speleogenesis. Individual occurrences of hypogene karst phenomena associated with the central Pecos River Valley are widespread throughout the greater Delaware Basin region, including development in a wide range of Permian carbonate and evaporate fades. Hypogene occurrences are well-documented as far north as Santa Rosa, New Mexico and as far south as Lake Amistad, Texas. Throughout …

Structured Decision Making As A Conceptual Framework To Identify Thresholds For Conservation And Management, Julien Martin, Michael C. Runge, James D. Nichols, Bruce C. Lubow, William L. Kendall

United States Geological Survey: Staff Publications

Thresholds and their relevance to conservation have become a major topic of discussion in the ecological literature. Unfortunately, in many cases the lack of a clear conceptual framework for thinking about thresholds may have led to confusion in attempts to apply the concept of thresholds to conservation decisions. Here, we advocate a framework for thinking about thresholds in terms of a structured decision making process. The purpose of this framework is to promote a logical and transparent process for making informed decisions for conservation.

Specification of such a framework leads naturally to consideration of definitions and roles of different kinds …

Tambellup-Borden Land Resources Survey, Angela Stuart-Street, Rohan Marold

Land resources series

No abstract provided.

The Initial Hydrological Effect Of Deep Drains At Wallatin Creek : (2006-2008), Richard J. George Dr, Grantley Stainer

Resource management technical reports

No abstract provided.

Setting Targets For Resource Condition In Upper Crossman Catchment, Leon Vanwyk, Gregory Paul Raper

Resource management technical reports

No abstract provided.

The Impact Of The "Profitable Perennials" Project On Adoption : An Evaluation, Jamie Bowyer, Rebecca Heath

Resource management technical reports

No abstract provided.

Wilson Inlet Catchment Appraisal 2007, Ron Master

Resource management technical reports

No abstract provided.

Estimating Survival Of Precocial Chicks During The Prefledging Period Using A Catch-Curve Analysis And Count-Based Age-Class Data, Conor P. Mcgowan, Joshua J. Millspaugh, Mark R. Ryan, Casey D. Kruse, Greg Pavelka

United States Army Corps of Engineers, Omaha District

ABSTRACT: Estimating reproductive success for birds with pre-cocial young can be difficult because chicks leave nests soon after hatching and individuals or broods can be difficult to track. Researchers often turn to estimating survival during the pre-fledging period and, though effective, mark-recapture based approaches are not always feasible due to cost, time, and animal welfare concerns. Using a threatened population of Piping Plovers (Charadrius melodus) that breeds along the Missouri River, we present an approach for estimating chick survival during the pre-fledging period using long-term (1993–2005), count-based, age-class data. We used a modified catch-curve analysis, and data collected …

Marchagee Oil Mallee Study : Drill Completion And Preliminary Hydrogeological Report, D L. Bennett, Adrian Goodreid

Resource management technical reports

No abstract provided.

Channel Morphology And Bed Sediment Characteristics Before And After Habitat Enhancement Activities In The Uridil Property, Platte River, Nebraska, Water Years 2005–2008, Paul J. Kinzel

United States Geological Survey: Publications

Fluvial geomorphic data were collected by the United States Geological Survey from July 2005 to June 2008 (a time period within water years 2005 to 2008) to monitor the effects of habitat enhancement activities conducted in the Platte River Whooping Crane Maintenance Trust’s Uridil Property, located along the Platte River, Nebraska. The activities involved the removal of vegetation and sand from the tops of high permanent islands and the placement of the sand into the active river channel. This strategy was intended to enhance habitat for migratory water birds by lowering the elevations of the high islands, thereby eliminating a …

A System For Estimating Bowen Ratio And Evaporation From Waste Lagoons, Arturo I. Quintanar, Rezaul Mahmood, John H. Loughrin, Nanh Lovanh, Monica V. Motley

High Plains Regional Climate Center: Staff Publications

A low‐cost system was deployed above a swine waste lagoon to obtain estimates of Bowen ratios and characterize lagoon temperatures. The system consisted of humidity and temperature sensors and anemometers deployed above the lagoon, water temperature sensors, and a meteorological station located by the lagoon. To evaluate the system, data was analyzed from the 25th through 28th June 2007. Bowen ratios showed diurnal behavior near the lagoon surface characterized by negative values during day and positive ones at night. Latent (evaporation) and sensible heat fluxes were towards the atmosphere and the lagoon, respectively for most of the day. A diurnal …

Clues To The Medieval Destabilization Of The Nebraska Sand Hills, Usa, From Ancient Pocket Gopher Burrows, Rebecca L. Schmeisser, David B. Loope, David A. Wedin

Department of Earth and Atmospheric Sciences: Faculty Publications

The Nebraska Sand Hills are a stabilized dune field in the central United States that reflect past conditions of drought. The most recent drought, known as the Medieval Climatic Anomaly, occurred from A.D. 900 to A.D. 1300 and had an enormous effect on the thriving prairie ecosystem, which included large populations of the plains pocket gopher (Geomys bursarius). Burrows of these organisms across a paleosol-eolian sand boundary in the Sand Hills indicate abrupt climate change during the transition from stabilized to active dune field and from humid to arid conditions. Medieval gophers tunneled at greater depths below the …

Effects Of Land Cover Variability On Evapotranspiration In The Llanganuco Valley, Aimee Higgins

Undergraduate Review

A process-based understanding of the effect land cover has on evapotranspiration (ET) in alpine valleys is lacking. It is conventionally assumed that ET is a negligible part of the water cycle in the Peruvian Andes, a critical source of water for the local inhabitants, due to lack of precipitation during the 6-month dry season and high humidity during the 6-month wet season. However, recent research findings from an embedded sensor network indicate that ET is in fact an important part of the Andean water cycle in Peru. Water resources within Peru are affected by the glaciers within the Cordillera Blanca, …

Mitigation Under Section 404 Of The Clean Water Act: Where It Comes From, What It Means, Palmer Hough, Morgan Robertson

United States Environmental Protection Agency: Publications

The requirement to mitigate impacts to wetlands and streams is a frequently misunderstood policy with a long and complicated history. We narrate the history of mitigation since the inception of the Clean Water Act Section 404 permit program in 1972, through struggles between the US Environmental Protection Agency and the US Army Corps of Engineers, through the emerging importance of wetland conservation on the American political landscape, and through the rise of market-based approaches to environmental policy. Mitigation, as it is understood today, was not initially foreseen as a component of the Section 404 permitting program, but was adapted from …

Thresholds Of Climate Change In Ecosystems: Final Report, Synthesis And Assessment Product 4.2, Craig D. Allen, Charles Birkeland, F. Stuart Chapin, Iii, Peter M. Groffman, Glenn . R. Guntenspergen, Alan K. Knapp, A. David Mcguire, Patrick J. Mulholland, Debra P.C. Peters, Daniel D. Roby, George Sugihara

United States Geological Survey: Publications

As defined in this Synthesis and Assessment Report, ‘an ecological threshold is the point at which there is an abrupt change in an ecosystem quality, property, or phenomenon, or where small changes in one or more external conditions produce large and persistent responses in an ecosystem’.
Ecological thresholds occur when external factors, positive feedbacks, or nonlinear instabilities in a system cause changes to propagate in a domino-like fashion that is potentially irreversible. This report reviews threshold changes in North American ecosystems that are potentially induced by climatic change and addresses the significant challenges these threshold crossings impose on resource and …

Water-Level Changes In The High Plains Aquifer, Predevelopment To 2007, 2005–06, And 2006–07, V. L. Mcguire

United States Geological Survey: Publications

The High Plains aquifer underlies 111.6 million acres (174,000 square miles) in parts of eight States—Colorado, Kansas, Nebraska, New Mexico, Oklahoma, South Dakota, Texas, and Wyoming. Water-level declines began in parts of the High Plains aquifer soon after the beginning of substantial irrigation with ground water in the aquifer area. This report presents water-level changes in the High Plains aquifer from the time before substantial ground-water irrigation development had occurred (about 1950 and termed “predevelopment” in this report) to 2007, from 2005–06, and from 2006–07. The report also presents the percentage change in saturated thickness of the aquifer, from predevelopment …

Quantifying Equid Behavior—A Research Ethogram For Free-Roaming Feral Horses, Jason I. Ransom, Brian S. Cade

United States Geological Survey: Publications

Feral horses (Equus caballus) are globally distributed in free-roaming populations on all continents except Antarctica and occupy a wide range of habitats including forest, grassland, desert, and montane environments. The largest populations occur in Australia and North America and have been the subject of scientific study for decades, yet guidelines and ethograms for feral horse behavioral research are largely absent in the scientific literature. The U.S. Geological Survey (USGS) Fort Collins Science Center conducted research on the influences of the immunocontraceptive porcine zona pellucida (PZP) on feral horse behavior from 2003–2006 in three discrete populations in the American …

Climate Change And Water Resources Management: A Federal Perspective, Levi D. Brekke, Julie E. Kiang, J. Rolf Olsen, Roger S. Pulwarty, David A. Raff, D. Phil Turnipseed, Robert S. Webb, Kathleen D. White

United States Geological Survey: Publications

Many challenges, including climate change, face the Nation’s water managers. The Intergovernmental Panel on Climate Change (IPCC) has provided estimates of how climate may change, but more understanding of the processes driving the changes, the sequences of the changes, and the manifestation of these global changes at different scales could be beneficial. Since the changes will likely affect fundamental drivers of the hydrological cycle, climate change may have a large impact on water resources and water resources managers.

The purpose of this interagency report prepared by the U.S. Geological Survey (USGS), U.S. Army Corps of Engineers (USACE), Bureau of Reclamation …

Circulation And Water Property Variations In The Nearshore Alaskan Beaufort Sea (1999 – 2007), Thomas J. Weingartner, Seth L. Danielson, Jeremy L. Kasper, Stephen R. Okkonen

United States Geological Survey: Publications

Six years of current meter and water property data were collected year-round (1999 – 2007) from the landfast ice zone of the nearshore Alaskan Beaufort Sea (ABS). The data show large seasonal differences in the circulation that is defined by the set-up and breakup of the landfast ice. During the open water season (July – mid-October) mid-depth currents often exceed 20 cm-s-1, whereas during the landfast ice season (mid-October – June) these currents are generally <10 cm-s^-1. Tidal currents are feeble (<3 cm-s^-1) year-round and probably do not play a dynamically significant role on the inner shelf.

Most ( …

Structured Decision Making As A Conceptual Framework To Identify Thresholds For Conservation And Management, Julien Martin, Michael C. Runge, James D. Nichols, Bruce C. Lubow, William L. Kendall2

United States Geological Survey: Staff Publications

Threshold and their relevance to conservation have become a major topic of discussion in the ecological literature. Unfortunately, in many cases the lack of a clear conceptual framework for thinking about thresholds in terms of a structured decision making process. The purpose of this framework is to promote a logical and transparent process for making informed decisions for conservation.

Specification of such a framework leads naturally to consideration of definitions and roles of different kinds of thresholds in the process. We distinguish among three categories of thresholds. Ecological thresholds are values of system state variables at which small changes bring …

Riparian And Associated Habitat Characteristics Related To Nutrient Concentrations And Biological Responses Of Small Streams In Selected Agricultural Areas, United States, 2003–04, Ronald B. Zelt, Mark D. Munn

United States Geological Survey: Publications

Physical factors, including both in-stream and riparian habitat characteristics that limit biomass or otherwise regulate aquatic biological condition, have been identified by previous studies. However, linking the ecological significance of nutrient enrichment to habitat or landscape factors that could allow for improved management of streams has proved to be a challenge in many regions, including agricultural landscapes, where many ecological stressors are strong and the variability among watersheds typically is large. Riparian and associated habitat characteristics were sampled once during 2003–04 for an intensive ecological and nutrients study of small perennial streams in five contrasting agricultural landscapes across the United …

Environmental Contaminants In Freshwater Fish And Their Risk To Piscivorous Wildlife Based On A National Monitoring Program, Jo Ellen Hinck, Christopher J. Schmitt, Kimberly A. Chojnacki, Donald E. Tillitt

United States Geological Survey: Staff Publications

Organochlorine chemical residues and elemental concentrations were measured in piscivorous and benthivorous fish at 111 sites from large U.S. river basins. Potential contaminant sources such as urban and agricultural runoff, industrial discharges, mine drainage, and irrigation varied among the sampling sites. Our objectives were to provide summary statistics for chemical contaminants and to determine if contaminant concentrations in the fish were a risk to wildlife that forage at these sites. Concentrations of dieldrin, total DDT, total PCBs, toxaphene, TCDDEQ, cadmium, chromium, mercury, lead, selenium, and zinc exceeded toxicity thresholds to protect fish and piscivorous wildlife in samples from at least …

Age-Distribution Estimation For Karst Groundwater: Issues Of Parameterization And Complexity In Inverse Modeling By Convolution, Andrew J. Long, Larry D. Putnam

United States Geological Survey: Staff Publications

Convolution modeling is useful for investigating the temporal distribution of groundwater age based on environmental tracers. The framework of a quasi-transient convolution model that is applicable to two-domain flow in karst aquifers is presented. The model was designed to provide an acceptable level of statistical confidence in parameter estimates when only chlorofluorocarbon (CFC) and tritium (³H) data are available. We show how inverse modeling and uncertainty assessment can be used to constrain model parameterization to a level warranted by available data while allowing major aspects of the flow system to be examined. As an example, the model was …

Use Of Osl Dating To Establish The Stratigraphic Framework Of Quaternary Eolian Sediments, Anton Scarp Upper Trench, Northeastern Colorado High Plains, Usa, Shannon A. Mahan, David C. Noe, James P. Mccalpin

United States Geological Survey: Staff Publications

This paper contains the results of the optically stimulated luminescence (OSL) datingused to establish stratigraphic ages and relationships of eolian sediments in a trench in northeastern Colorado,USA. This trench was located in the upper face of the Anton scarp, a major topographic lineament trending NW–SE for a distance of 135 km, in anticipation of intersecting near-surface faulting. The trench was 180 m long, 4.5–6.0 m deep, and exposed 22 m of stratigraphic section, most of which dipped gently west and was truncated by gulley channeling at the face of the scarp. No direct evidence of faulting was found in the …

Behavior And Reproductive Success Of Rock Sandpipers Breeding On The Yukon-Kuskokwim River Delta, Alaska, Matthew Johnson, Jesse R. Conklin, Branden L. Johnson, Brian J. Mccaffery, Susan M. Haig, Jeffrey R. Walters

United States Geological Survey: Staff Publications

We studied Rock Sandpiper (Calidris ptilocnemis) breeding behavior and monitored reproductive success from 1998 to 2005 on the Yukon-Kuskokwim River Delta, Alaska, USA. We banded 24 adults and monitored 45 nests. Annual return rate of adults ranged between 67 and 100%. Six pairs of Rock Sandpipers bred at our study site for ≥ 2 years, and among these we did not observe mate change (i.e., when both members of a pair returned and each mated with a new individual). Nests were typically initiated by mid-May and 53% of females laid second clutches if first clutches were lost through …

The Neoglacial Landscape And Human History Of Glacier Bay, Glacier Bay National Park And Preserve, Southeast Alaska, Usa, Cathy Connor, Greg Streveler, Austin Post, Daniel Monteith, Wanye Howell

United States Geological Survey: Staff Publications

The Neoglacial landscape of the Huna Tlingit homeland in Glacier Bay is recreated through new interpretations of the lower Bay’s fjordal geomorphology, late Quaternary geology and its ethnographic landscape. Geological interpretation is enhanced by 38 radiocarbon dates compiled from published and unpublished sources, as well as 15 newly dated samples. Neoglacial changes in ice positions, outwash and lake extents are reconstructed for c. 5500–200 cal. yr ago, and portrayed as a set of three landscapes at 1600–1000, 500–300 and 300–200 cal. yr ago. This history reveals episodic ice advance towards the Bay mouth, transforming it from a fjordal seascape into …

Porosity And Permeability In Ternary Sediment Mixtures, Jason Dennis Esselburn

Browse all Theses and Dissertations

Porosity and permeability were measured in mixtures of fine, medium, and coarse sand, where the volume fraction of each of the three components was systematically varied. The porosity varies non-linearly with the volume fractions, and can be modeled with a piecewise-linear approach. The permeability also varies non-linearly with the volume fractions. Permeability can be modeled with the Kozeny-Carman equation using a recursive approach for computing the representative grain size from those of the components in the mixture.