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Terpenes And Carbohydrate Source Influence Rumen Fermentation, Digestibility, Intake, And Preference In Sheep, J. J. Villalba, F. D. Provenza, K. C. Olson Jan 2006

Terpenes And Carbohydrate Source Influence Rumen Fermentation, Digestibility, Intake, And Preference In Sheep, J. J. Villalba, F. D. Provenza, K. C. Olson

Green Canyon Environmental Research Area, Logan Utah

We hypothesized that toxins and nutrients in foods interact to influence foraging behavior by herbivores. Based on this hypothesis we predicted that 1) terpenes in big sagebrush (Artemisia tridentata) influence intake and preference in sheep for diets varying in sources of nonstructural (barley grain) and structural (sugar beet pulp) carbohydrates, and 2) these effects are due to the differential effects of terpenes on fermentation products and apparent digestibility of each class of carbohydrates. Lambs were fed 2 isoenergetic and isonitrogenous diets with varying proportions of the same ingredients (beet pulp- and barley grain-based diet) or offered a choice between the …


An Examination Of External Influences Imbedded In The Historical Snow Data Of Utah, Randall P. Julander, Michael Bricco Jan 2006

An Examination Of External Influences Imbedded In The Historical Snow Data Of Utah, Randall P. Julander, Michael Bricco

All U.S. Government Documents (Utah Regional Depository)

Snowpack data collection has a long and storied history in Utah as well as the western United States. Many researchers use historical snow course data for various applications ranging from water supply forecasting to climate change. These data are far from a perfect data set and data users should know the errors and limitations within them. In the current setting, only those collecting the data have access to the raw data and the site biographical information. In Utah, records extend back to at least 1912. Systematic measurements began in the mid 1920's with many long term snow courses established at …


Acoustic Stratigraphy Of Bear Lake, Utah–Idaho—Late Quaternary Sedimentation Patterns In A Simple Half-Graben, Steven M. Colman Jan 2006

Acoustic Stratigraphy Of Bear Lake, Utah–Idaho—Late Quaternary Sedimentation Patterns In A Simple Half-Graben, Steven M. Colman

United States Geological Survey: Staff Publications

A277-km network of high-resolution seismic-reflection profiles, supplemented with a sidescan-sonar mosaic of the lake floor, was collected in Bear Lake, Utah–Idaho, in order to explore the sedimentary framework of the lake’s paleoclimate record. The acoustic stratigraphy is tied to a 120 m deep, continuously cored drill hole in the lake. Based on the age model for the drill core, the oldest continuously mapped acoustic reflector in the data set has an age of about 100 ka, although older sediments were locally imaged.

The acoustic stratigraphy of the sediments below the lake indicates that the basin developed primarily as a simple …


The Geochemical Record Of The Last 17,000 Years In The Guaymas Basin, Gulf Of California, Walter E. Dean Jan 2006

The Geochemical Record Of The Last 17,000 Years In The Guaymas Basin, Gulf Of California, Walter E. Dean

United States Geological Survey: Staff Publications

Sediments deposited on the western slope of the Guaymas Basin in the central Gulf of California are composed predominantly of detrital clastic material and biogenic silica (biopal), with minor organic material (average of 2.8% organic carbon) and calcium carbonate. The CaCO3 is derived from calcareous plankton and is highly variable ranging from 0% to 16%. In general, the CaCO3 content of the sediments varies inversely with the biopal content, reflecting the relative abundance of calcareous and siliceous plankton in the photic zone. Siliceous plankton dominate when winds are predominantly out of the northwest producing strong upwelling. Calcareous plankton …


Evaluation Of Cauliflower And Broccoli Varieties: Autumn Planting (January - May 2006), Kristen Stirling Jan 2006

Evaluation Of Cauliflower And Broccoli Varieties: Autumn Planting (January - May 2006), Kristen Stirling

Horticulture research reports

This document has been prepared from a cauliflower and broccoli variety evaluation trial conducted at the Manjimup Horticultural Research Institute, South Western Highway, Manjimup WA 6258. The results reflect the growth characteristics, yield, quality and density of the cauliflower and broccoli varieties as recorded at this site during the conditions of the growing period (January to May 2006).

This report is the second in a series of four produced from the evaluation of cauliflower and broccoli varieties conducted at the Manjimup Horticultural Research Institute. The results are provided to allow seed suppliers, seedling nurseries, producers, packers and marketers to identify …


Soil-Landscapes Of Western Australia's Rangelands And Arid Interior, Peter J. Tille Jan 2006

Soil-Landscapes Of Western Australia's Rangelands And Arid Interior, Peter J. Tille

Resource management technical reports

This report documents the process of placing the most recent and detailed mapping of Western Australia's Rangelands and Arid interior that is available into a hierarchy of soil-landscape mapping units. It also provides descriptions of the soil-landscape regions, provinces and zones identified.


Evaluation Of The Sustainable Grazing On Saline Lands - Wa Producer Network : Influence On Practice Change And Decision-Making Capacity, Rebecca Heath, Jamie Bowyer, T M. Lacey Jan 2006

Evaluation Of The Sustainable Grazing On Saline Lands - Wa Producer Network : Influence On Practice Change And Decision-Making Capacity, Rebecca Heath, Jamie Bowyer, T M. Lacey

Resource management technical reports

No abstract provided.


Multicriteria Decision Analysis: A Comprehensive Decision Approach For Management Of Contaminated Sediments, I Linkov, F K. Satterstrom, G Kiker, T P. Seager, T Bridges, K H. Gardener, S H. Rodgers, D A. Belluck, A Meyer Jan 2006

Multicriteria Decision Analysis: A Comprehensive Decision Approach For Management Of Contaminated Sediments, I Linkov, F K. Satterstrom, G Kiker, T P. Seager, T Bridges, K H. Gardener, S H. Rodgers, D A. Belluck, A Meyer

United States Army Corps of Engineers, Omaha District

Contaminated sediments and other sites present a difficult challenge for environmental decision makers. They are typically slow to recover or attenuate naturally, may involve multiple regulatory agencies and stakeholder groups, and engender multiple toxicological and ecotoxicological risks. While environmental decision-making strategies over the last several decades have evolved into increasingly more sophisticated, information-intensive, and complex approaches, there remains considerable dissatisfaction among business, industry, and the public with existing management strategies. Consequently, contaminated sediments and materials are the subject of intense technology development, such as beneficial reuse or in situ treatment. However, current decision analysis approaches, such as comparative risk assessment, …


Origin Of Gabbroic Xenoliths Within The Lone Mountain Dacite Intrusion, Big Sky, Montana: A Field And Petrographic Analysis, Emily Clement Jan 2006

Origin Of Gabbroic Xenoliths Within The Lone Mountain Dacite Intrusion, Big Sky, Montana: A Field And Petrographic Analysis, Emily Clement

Undergraduate Review

No abstract provided.


Microstructural Analysis Of A Drill Core From The Rhode Island Formation: Upper 750 Feet, Ashlee Kirkwood Jan 2006

Microstructural Analysis Of A Drill Core From The Rhode Island Formation: Upper 750 Feet, Ashlee Kirkwood

Undergraduate Review

No abstract provided.


The Sparrow Surface Water-Quality Model: Theory, Application And User Documentation, G. E. Schwarz, A. B. Hoos, R. B. Alexander, R. A. Smith Jan 2006

The Sparrow Surface Water-Quality Model: Theory, Application And User Documentation, G. E. Schwarz, A. B. Hoos, R. B. Alexander, R. A. Smith

United States Geological Survey: Publications

SPARROW (SPAtially Referenced Regressions On Watershed attributes) is a watershed modeling technique for relating water-quality measurements made at a network of monitoring stations to attributes of the watersheds containing the stations. The core of the model consists of a nonlinear regression equation describing the non-conservative transport of contaminants from point and diffuse sources on land to rivers and through the stream and river network. The model predicts contaminant flux, concentration, and yield in streams and has been used to evaluate alternative hypotheses about the important contaminant sources and watershed properties that control transport over large spatial scales.

This report provides …


Predicting The Percent Live Cover Of Corals: An In Situ Remote Sensing Approach, Deepak R. Mishra, Sunil Narumalani, Ronald Bahl, D. Rundquist, Merlin P. Lawson Jan 2006

Predicting The Percent Live Cover Of Corals: An In Situ Remote Sensing Approach, Deepak R. Mishra, Sunil Narumalani, Ronald Bahl, D. Rundquist, Merlin P. Lawson

Center for Advanced Land Management Information Technologies: Publications

Percent reflectance of corals is perhaps the most important remotely sensed data that can be related to their biophysical properties. Because most of the biophysical variables of corals (i.e., pigment content, live cover and algal overgrowth) are related to their reflectance spectra, the analysis and inversion of the spectra may provide an account of these variables. Our research was aimed at determining the relationship between the percent live cover and reflectance of corals. Two wavelength bands (405–425 nm, and 590–600 nm) were identified to establish the relationship. A linear relationship was observed, which showed higher correlation (R2 = …


Use Of Sediment Rating Curves And Optical Backscatter Data To Characterize Sediment Transport In The Upper Yuba River Watershed, California, 2001–03, Jennifer A. Curtis, Lorraine E. Flint, Charles N. Alpers, Scott A. Wright, Noah P. Snyder Jan 2006

Use Of Sediment Rating Curves And Optical Backscatter Data To Characterize Sediment Transport In The Upper Yuba River Watershed, California, 2001–03, Jennifer A. Curtis, Lorraine E. Flint, Charles N. Alpers, Scott A. Wright, Noah P. Snyder

United States Geological Survey: Publications

Sediment transport in the upper Yuba River watershed, California, was evaluated from October 2001 through September 2003. This report presents results of a three-year study by the U.S. Geological Survey, in cooperation with the California Ecosystem Restoration Program of the California Bay–Delta Authority and the California Resources Agency. Streamflow and suspended-sediment concentration (SSC) samples were collected at four gaging stations; however, this report focuses on sediment transport at the Middle Yuba River (11410000) and the South Yuba River (11417500) gaging stations. Seasonal suspended-sediment rating curves were developed using a group-average method and non-linear least-squares regression. Bed-load transport relations were used …


Spring Census Of Mid-Continent Sandhill Cranes Using Aerial Infrared Videography, Paul Kinzel, Jonathan Nelson, Randolph Parker, Lawrence Davis Jan 2006

Spring Census Of Mid-Continent Sandhill Cranes Using Aerial Infrared Videography, Paul Kinzel, Jonathan Nelson, Randolph Parker, Lawrence Davis

United States Geological Survey: Staff Publications

Aerial infrared videography was used to map spatial distributions of nocturnal sandhill crane (Grus canadensis) flocks and determine crane densities within roosts as an alternative to the currently used diurnal photo-corrected ocular transect method to estimate the size of the midcontinental population. The densities determined from samples taken over the course of a night show variability. Densities measured early in the night (2100 to 2300 hrs) were generally lower than those measured in the time period after midnight and up until cranes prepared to depart their roosts before sunrise. This suggests that cranes may be more active early …


Widespread Presence Of Naturally Occurring Perchlorate In High Plains Of Texas And New Mexico, Srinath Rajagopalan, Todd Anderson, Lynne Fahlquist, Ken Rainwater, Moira Ridley, W. Andrew Jackson Jan 2006

Widespread Presence Of Naturally Occurring Perchlorate In High Plains Of Texas And New Mexico, Srinath Rajagopalan, Todd Anderson, Lynne Fahlquist, Ken Rainwater, Moira Ridley, W. Andrew Jackson

United States Geological Survey: Staff Publications

Perchlorate (ClO4-) occurrence in groundwater has previously been linked to industrial releases and the historic use of Chilean nitrate fertilizers. However, recently a number of occurrences have been identified for which there is no obvious anthropogenic source. Groundwater from an area of 155 000 km2 in 56 counties in northwest Texas and eastern New Mexico is impacted by the presence of ClO4-. Concentrations were generally low (<4 ppb), although some areas are impacted by concentrations up to 200 ppb. ClO4- distribution is not related to well type (public water system, domestic, agricultural, or water-table monitoring) or aquifer (Ogallala, Edward Trinity High Plains, Edwards Trinity …


Simulation Of Solute Movement Through Wellbores To Characterize Public Supply Well Contaminant Vulnerability In The High Plains Aquifer, York, Nebraska, Brian R. Clark, Matthew K. Landon, Leon J. Kauffman, George Z. Hornberger Jan 2006

Simulation Of Solute Movement Through Wellbores To Characterize Public Supply Well Contaminant Vulnerability In The High Plains Aquifer, York, Nebraska, Brian R. Clark, Matthew K. Landon, Leon J. Kauffman, George Z. Hornberger

United States Geological Survey: Staff Publications

A ground-water flow and transport model simulating contaminant movement to public supply wells in the High Plains aquifer near York, Nebraska was developed as part of the U.S. Geological Survey National Water-Quality Assessment Program. Water-quality samples were collected from wells screened in unconfined and confined units. Samples collected from a public supply well and selected monitoring wells completed in the confined aquifer have chemistry and age-tracer concentrations consistent with a mix of young water from unconfined recharge areas combined with relatively older confined aquifer water. These results imply that there are preferential flow paths that permit shallow recharge water and …


Change In Atmospheric Mineral Aerosols In Response To Climate: Last Glacial Period, Preindustrial, Modern, And Doubled Carbon Dioxide Climates, Natalie M. Mahowald, Daniel R. Muhs, Samuel Levis, Philip J. Rasch, Masaru Yoshioka, Charles S. Zender, Chao Luo Jan 2006

Change In Atmospheric Mineral Aerosols In Response To Climate: Last Glacial Period, Preindustrial, Modern, And Doubled Carbon Dioxide Climates, Natalie M. Mahowald, Daniel R. Muhs, Samuel Levis, Philip J. Rasch, Masaru Yoshioka, Charles S. Zender, Chao Luo

United States Geological Survey: Staff Publications

Desert dust simulations generated by the National Center for Atmospheric Research’s Community Climate System Model for the current climate are shown to be consistent with present day satellite and deposition data. The response of the dust cycle to last glacial maximum, preindustrial, modern, and doubled-carbon dioxide climates is analyzed. Only natural (non-land use related) dust sources are included in this simulation.


Cougars In Kansas, Charles D. Lee, Alyssa E. Warneke, Mike Houts, Troy R. Livingston, Philip S. Gipson Jan 2006

Cougars In Kansas, Charles D. Lee, Alyssa E. Warneke, Mike Houts, Troy R. Livingston, Philip S. Gipson

United States Geological Survey: Staff Publications

The presence of the cougar (Puma concolor) in the state of Kansas is a controversial issue. Since 1999, 234 cougar sightings have been reported to the Extension Wildlife Specialist at Kansas State University. To those who have reported such sightings, the existence of cougars in Kansas is undeniable. Others, however, question the validity of such sightings as providing evidence of cougars. After surveying other governmental agencies and organizations, we discovered that acceptable identification criteria for rare or unusual felines included things beside sightings: voucher specimens, DNA from hair or scat, tracks, prey carcasses, and photographs or videos. The …


Historical And Current Status Of Elk In Kansas, Jonathan M. Conard, Philip S. Gipson, Matt Peek Jan 2006

Historical And Current Status Of Elk In Kansas, Jonathan M. Conard, Philip S. Gipson, Matt Peek

United States Geological Survey: Staff Publications

Elk (Cervus elaphus) historically occurred throughout Kansas but were extirpated from the state around 1890. Free-ranging elk populations were reestablished in Kansas through reintroduction efforts on Cimarron National Grasslands from 1981-1990, and on Fort Riley Military Installation from 1986-1994. Current elk distributions in the state have not been published following these reintroduction efforts. The current and historical distribution of this species in Kansas is described.


Measuring Groundwater–Surface Water Interaction And Its Effect On Wetland Stream Benthic Productivity, Trout Lake Watershed, Northern Wisconsin, Usa, Randall J. Hunt, Mac Strand, John F. Walker Jan 2006

Measuring Groundwater–Surface Water Interaction And Its Effect On Wetland Stream Benthic Productivity, Trout Lake Watershed, Northern Wisconsin, Usa, Randall J. Hunt, Mac Strand, John F. Walker

United States Geological Survey: Staff Publications

Measurements of groundwater–surface water exchange at three wetland stream sites were related to patterns in benthic productivity as part of the US Geological Survey’s Northern Temperate Lakes–Water, Energy and Biogeochemical Budgets (NTL–WEBB) project. The three sites included one high groundwater discharge (HGD) site, one weak groundwater discharge (WGD) site, and one groundwater recharge (GR) site. Large upward vertical gradients at the HGD site were associated with smallest variation in head below the stream and fewest gradient reversals between the stream and the groundwater beneath the stream, and the stream and the adjacent streambank. The WGD site had the highest number …


Taxonomic Considerations In Listing Subspecies Under The U.S. Endangered Species Act, Susan M. Haig, Erik A. Beever, Steven M. Chambers, Hope M. Draheim, Bruce D. Dugger, Susie M. Dunham, Elise Elliott-Smith, Joseph B. Fontaine, Dylan C. Kesler, Brian J. Knaus, Iara F. Lopes, Pete Loschl, Thomas D. Mullins, Lisa M. Sheffield Jan 2006

Taxonomic Considerations In Listing Subspecies Under The U.S. Endangered Species Act, Susan M. Haig, Erik A. Beever, Steven M. Chambers, Hope M. Draheim, Bruce D. Dugger, Susie M. Dunham, Elise Elliott-Smith, Joseph B. Fontaine, Dylan C. Kesler, Brian J. Knaus, Iara F. Lopes, Pete Loschl, Thomas D. Mullins, Lisa M. Sheffield

United States Geological Survey: Staff Publications

The U.S. Endangered Species Act (ESA) allows listing of subspecies and other groupings below the rank of species. This provides the U.S. Fish and Wildlife Service and the National Marine Fisheries Service with a means to target the most critical unit in need of conservation. Although roughly one-quarter of listed taxa are subspecies, these management agencies are hindered by uncertainties about taxonomic standards during listing or delisting activities. In a review of taxonomic publications and societies, we found few subspecies lists and none that stated standardized criteria for determining subspecific taxa. Lack of criteria is attributed to a centuries-old debate …


Conserving Biodiversity In Human-Dominated Landscapes, Dale D. Goble, J. Michael Scott, Frank W. Davis Jan 2006

Conserving Biodiversity In Human-Dominated Landscapes, Dale D. Goble, J. Michael Scott, Frank W. Davis

United States Geological Survey: Staff Publications

The two volumes of The Endangered Species Act at Thirty look backward to evaluate the effectiveness of the act over its first three decades (Wilcove and McMillan 2006; Scott et al. 2006, chap. 2; Goble, this volume; Svancara, this volume; Callicott, this volume; Norton, this volume) and also forward to suggest how it can be used as a cornerstone for conserving biological diversity in increasingly human-dominated landscapes (Davis et al. 2006; Bean 2006). The chapters in part 2 of this volume, for example, appraise the science of the 1990s and 2000s at both the large scale (Lomolino, this volume; Naeem …


Endangered Species Time Line, Leona K. Svancara, J. Michael Scott, Dale D. Goble, Frank W. Davis, Donna Brewer Jan 2006

Endangered Species Time Line, Leona K. Svancara, J. Michael Scott, Dale D. Goble, Frank W. Davis, Donna Brewer

United States Geological Survey: Staff Publications

The Endangered Species Act (ESA) is embedded in a web of statutes designed to regulate relationships between humans and other species that stretch back nearly a millennium (Goble, this volume; Goble and Freyfogle 2002). This chapter presents a time line of federal actions taken to protect wildlife beginning with passage of the Land and Water Conservation Fund Act in 1963 (Act of May 28, 1963). Earlier laws to protect wildlife are discussed elsewhere (Goble, this volume). The time line emphasizes federal actions that conserve species at risk of extinction and significant events in the course of implementing the Endangered Species …


Isotope Sourcing Of Prehistoric Willow And Tule Textiles Recovered From Western Great Basin Rock Shelters And Caves: Proof Of Concept, Larry V. Benson, E. M. Hattori, H. E. Taylor, S. R. Poulson, E. A. Jolie Jan 2006

Isotope Sourcing Of Prehistoric Willow And Tule Textiles Recovered From Western Great Basin Rock Shelters And Caves: Proof Of Concept, Larry V. Benson, E. M. Hattori, H. E. Taylor, S. R. Poulson, E. A. Jolie

United States Geological Survey: Staff Publications

Isotope and trace-metal analyses were used to determine the origin of plants used to manufacture prehistoric textiles (basketry and matting) from archaeological sites in the western Great Basin. Research focused on strontium (87Sr/86Sr) and oxygen (18O/16O) isotope ratios of willow (Salix sp.) and tule (Schoenoplectus sp.), the dominant raw materials in Great Basin textiles. The oxygen-isotope data indicated that the willow and tule used to produce the textiles were harvested from the banks of rivers or in marshes characterized by flowing water and not from lakes or sinks. The strontium-isotope …


Contact Zone Permeability At Intrusion Boundaries: New Results From Hydraulic Testing And Geophysical Logging In The Newark Rift Basin, New York, Usa, Jurg M. Matter, D. S. Goldberg, Roger H. Morin, M. Stute Jan 2006

Contact Zone Permeability At Intrusion Boundaries: New Results From Hydraulic Testing And Geophysical Logging In The Newark Rift Basin, New York, Usa, Jurg M. Matter, D. S. Goldberg, Roger H. Morin, M. Stute

United States Geological Survey: Staff Publications

Hydraulic tests and geophysical logging performed in the Palisades sill and the underlying sedimentary rocks in the NE part of the Newark Rift Basin, New York, USA, confirm that the particular transmissive zones are localized within the dolerite-sedimentary rock contact zone and within a narrow interval below this contact zone that is characterized by the occurrence of small layers of chilled dolerite. Transmissivity values determined from fluid injection, aquifer testing, and flowmeter measurements generally fall in the range of 8.1E-08 to 9.95E-06 m2/s and correspond to various scales of investigation. The analysis of acoustic and optical BHTV images …


The Agricultural Productivity Of Chaco Canyon And The Source(S) Of Pre-Hispanic Maize Found In Pueblo Bonito, Larry Benson, John Stein, Howard Taylor, Richard Friedman, Thomas C. Windes Jan 2006

The Agricultural Productivity Of Chaco Canyon And The Source(S) Of Pre-Hispanic Maize Found In Pueblo Bonito, Larry Benson, John Stein, Howard Taylor, Richard Friedman, Thomas C. Windes

United States Geological Survey: Staff Publications

Agricultural productivity estimates suggest that the core area of Chaco Canyon could have sustained only a few hundred individuals. Modern analogues of existing Pueblo populations and their domestic habitations with Chaco structures suggest that Chaco at times had a resident population exceeding 2000 people. These data suggest that maize would have had to be imported to feed permanent residents and those visiting Chaco during ritual–political gatherings and those who participated in the accelerated construction and modification of great houses between AD 1030 and 1130. Comparison of strontium-isotope and trace-element ratios of synthetic soil and natural waters from sites within the …


Natural Resource Management Issues In The Avon River Basin, Paul Galloway Jan 2006

Natural Resource Management Issues In The Avon River Basin, Paul Galloway

Resource management technical reports

Analyses the risk of soil, land and water degradation within the Avon River Basin of Western Australia. Information is based on the interpretation of the characteristics of soils and landscapes within the Avon River basin. This report deals with 15 natural resource management issues and describes the extent of each issue, the impacts that each issue will have, management options that can be used to deal with each issue, and the effectiveness of each management option in dealing with the issues.


Unraveling The Geologic History Of The Avalon Terrane In Ma, Erin Nevens Jan 2006

Unraveling The Geologic History Of The Avalon Terrane In Ma, Erin Nevens

Undergraduate Review

No abstract provided.


Field, Petrographic, And Geochemical Characteristics Of Price Creek, Russ Mccormack Jan 2006

Field, Petrographic, And Geochemical Characteristics Of Price Creek, Russ Mccormack

Undergraduate Review

No abstract provided.


Microstructural Analysis Of The Rhode Island Formation, Narragansett Basin, Ma, Elizabeth Connell Jan 2006

Microstructural Analysis Of The Rhode Island Formation, Narragansett Basin, Ma, Elizabeth Connell

Undergraduate Review

No abstract provided.