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Articles 631 - 660 of 1807
Full-Text Articles 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
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 …
Subspecies Status And Population Genetic Structure In Piping Plover (Charadrius Melodus), Mark P. Miller, Susan M. Haig, Cheri L. Gratto-Trevor, Thomas D. Mullins
Subspecies Status And Population Genetic Structure In Piping Plover (Charadrius Melodus), Mark P. Miller, Susan M. Haig, Cheri L. Gratto-Trevor, Thomas D. Mullins
United States Geological Survey: Staff Publications
Piping Plover (Charadrius melodus) is a migratory shorebird that is listed as endangered in Canada and the U.S. Great Lakes and as threatened throughout the rest of its breeding and winter range. We undertook a comprehensive molecular-genetic investigation to (1) address subspecific taxonomy, (2) characterize population genetic structure, and (3) infer past bottlenecks and demographic processes in this species. Analyses included individuals from 23 U.S. states and Canadian provinces and were based on mitochondrial DNA sequences (580 base pairs, n = 245) and 8 nuclear microsatellite loci (n = 229). Our findings provide support for separate Atlantic and …
The Cleaning Of Burned And Contaminated Archaeological Maize Prior To 87sr/86sr Analysis, L.V. Benson, H. E. Taylor, T. I. Plowman, D. A. Roth, R. C. Antweiler
The Cleaning Of Burned And Contaminated Archaeological Maize Prior To 87sr/86sr Analysis, L.V. Benson, H. E. Taylor, T. I. Plowman, D. A. Roth, R. C. Antweiler
United States Geological Survey: Staff Publications
Accurate trace-metal and strontium-isotope analyses of archaeological corn cobs require that metal contaminants be removed prior to chemical analysis. Archaeological cobs are often coated with construction debris, dust, or soilwhich contains mineral particles. In addition, most archaeological cobs are partially or completely burned and the burned parts incorporate mineral debris in their hardened residual structures. Unburned cobs are weak ion exchangers and most metals within a cob are not firmly bound to cob organic matter; therefore, immersing cobs in acids and rinsing them in deionized water to remove mineral contaminants may result in the undesirable loss of metals, including strontium, …
Tree-Ring Dates And Demographic Change In The Southern Colorado Plateau And Rio Grande Regions, Michael S. Berry, Larry Benson
Tree-Ring Dates And Demographic Change In The Southern Colorado Plateau And Rio Grande Regions, Michael S. Berry, Larry Benson
United States Geological Survey: Staff Publications
In this chapter, tree-ring dates from the southern Colorado Plateau, Mogollon Highlands, and Rio Grande areas (fig. 3-1) (hereafter referred to as the study area) are used to estimate regional-scale timber-harvesting and construction activities between AD 600 and 1600 (the Basketmaker III through Pueblo IV periods). Within that time span, we focus our attention particularly on the AD 1045-1300 period, a time when anomalously wet periods alternated with megadroughts (fig. 3.2). Treering- date distributions (histograms) for eight archaeological subregions within the study area have been created using a database of more than twenty-four thousand tree-ring dates from archaeological sites. These …
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
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
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 …
The Role Of African Dust In The Formation Of Quaternary Soils On Mallorca, Spain And Implications For The Genesis Of Red Mediterranean Soils, Daniel R. Muhs, James Budahn, Anna Avila, Gary Skipp, Joshua Freeman, Deanna Patterson
The Role Of African Dust In The Formation Of Quaternary Soils On Mallorca, Spain And Implications For The Genesis Of Red Mediterranean Soils, Daniel R. Muhs, James Budahn, Anna Avila, Gary Skipp, Joshua Freeman, Deanna Patterson
United States Geological Survey: Staff Publications
African dust additions explain the origin of terra rossa soils that are common on the carbonate-platform island of Mallorca, Spain. Mineralogical and geochemical analyses indicate that Quaternary carbonate eolianites on Mallorca have a very high purity, usually composed of more than 90% carbonate minerals (calcite, dolomite, and aragonite). In contrast, terra rossa soils developed on these eolianites have lower carbonate contents and contain higher concentrations of quartz and other silicates. Analyses of immobile trace elements indicate that the non-carbonate fractions of the eolianites have distinctive Zr/Hf, La/Yb, Cr/Sc and Th/Ta values that differ from the superjacent terra rossa soils. These …
Assessing The Potential For Luminescence Dating Of Basalts, S. Tsukamoto, G. A.T. Duller, A. G. Wintle, Daniel R. Muhs
Assessing The Potential For Luminescence Dating Of Basalts, S. Tsukamoto, G. A.T. Duller, A. G. Wintle, Daniel R. Muhs
United States Geological Survey: Staff Publications
The possibility of dating basalt using luminescence was tested on four samples with independent age control from Cima volcanic !eld, California, with the ultimate aim of assessing whether the technique could be used to date sediments on the surface of Mars. Previous analysis of these samples had demonstrated that the infrared stimulated luminescence (IRSL) signal is most suitable for dating as it showed the lowest fading rate among various luminescence signals. In this study, changes in equivalent dose as a function of preheat are described. The ages for the two youngest Cima samples agree with the independent ages based on …
Nebraska Grout Task Force In-Situ Study Of Grout Material 2001 - 2006 And 2007 Dye Tests, Susan Olafsen Lackey, Will F. Myers, Thomas C. Christopherson, Jeffrey J. Gottula
Nebraska Grout Task Force In-Situ Study Of Grout Material 2001 - 2006 And 2007 Dye Tests, Susan Olafsen Lackey, Will F. Myers, Thomas C. Christopherson, Jeffrey J. Gottula
Conservation and Survey Division: Faculty and Staff Publications
No abstract provided.
Biogeochemical Behavior Of Dissolved Arsenic And Uranium Concentrations In Public Water Supply Wells, Kevin J. Mcvey
Biogeochemical Behavior Of Dissolved Arsenic And Uranium Concentrations In Public Water Supply Wells, Kevin J. Mcvey
School of Natural Resources: Dissertations, Theses, and Student Research
Public water supply (PWS) wells currently contain dissolved uranium concentrations above the federally mandated maximum contaminant level (MCL) of 30 ppb (parts per billion) and dissolved arsenic concentrations above the 10 ppb MCL. Both uranium and arsenic are known to cause various forms of cancer in humans. Variations in total uranium concentrations in PWS wells in Nebraska indicate a relationship to the duration and rate of pumping in specific wells. Although total arsenic concentrations show some variability over time in specific wells, the relationship to pumping is not as clear. Previous studies show that iron and sulfur bacteria present in …
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
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 …
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
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
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 …
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
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
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 …
Agate Fossil Beds National Monument: Geologic Resources Inventory Report, John Graham
Agate Fossil Beds National Monument: Geologic Resources Inventory Report, John Graham
United States National Park Service: Publications
This report accompanies the digital geologic map for Agate Fossil Beds National Monument in Nebraska, which the Geologic Resources Division produced in collaboration with its partners. It contains information relevant to resource management and scientific research. This document incorporates preexisting geologic information and does not include new data or additional fieldwork.
Formerly a working ranch in sparsely populated northwestern Nebraska, Agate Fossil Beds National Monument is one of the most important paleontological sites in the world for studying Miocene-age mammals and the evolving Miocene world which existed around 20 million years ago. The main bonebeds at Carnegie Hill and University …
Toxicity Of Polybrominated Diphenyl Ethers (De-71) In Chicken (Gallus Gallus), Mallard (Anas Platyrhynchos), And American Kestrel (Falco Sparverius) Embryos And Hatchlings, Moira A. Mckernan, Barnett A. Rattner, Robert C. Hales, Mary Ann Ottinger
Toxicity Of Polybrominated Diphenyl Ethers (De-71) In Chicken (Gallus Gallus), Mallard (Anas Platyrhynchos), And American Kestrel (Falco Sparverius) Embryos And Hatchlings, Moira A. Mckernan, Barnett A. Rattner, Robert C. Hales, Mary Ann Ottinger
United States Geological Survey: Staff Publications
Embryonic survival, pipping and hatching success, and sublethal biochemical, endocrine, and histological endpoints were examined in hatchling chickens (Gallus gallus), mallards (Anas platyrhynchos), and American kestrels (Falco sparverius) following air cell administration of a pentabrominated diphenyl ether (penta-BDE; DE-71) mixture (0.01–20 µg/g egg) or polychlorinated biphenyl (PCB) congener 126 (3,3’,4,4’,5-pentachlorobiphenyl; 0.002 µg/g egg). The penta-BDE decreased pipping and hatching success at concentrations of 10 and 20 µg/g egg in kestrels but had no effect on survival endpoints in chickens or mallards. Sublethal effects in hatchling chickens included ethoxyresorufin-O-dealkylase (EROD) induction and histological …
Eastern Nebraska Water Resources Assessment (Enwra): Introduction To A Hydrogeological Study, Dana Divine, R. Matthew Joeckel, Jesse T. Korus, P.R. Hanson, Sue Olafsen Lackey
Eastern Nebraska Water Resources Assessment (Enwra): Introduction To A Hydrogeological Study, Dana Divine, R. Matthew Joeckel, Jesse T. Korus, P.R. Hanson, Sue Olafsen Lackey
Conservation and Survey Division: Faculty and Staff Publications
No abstract provided.
Evaluating Lake Response To Environmental And Climatic Change Using Lake Core Records And Modeling, Brandi Bracht-Flyr
Evaluating Lake Response To Environmental And Climatic Change Using Lake Core Records And Modeling, Brandi Bracht-Flyr
Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research
This dissertation evaluates how lakes respond to changes in their environmental and climatic settings. This dissertation consists of two lake modeling projects and the environmental and paleoclimatic reconstructions of four lakes in southwestern Montana. Lakes and their associated biological communities respond to environmental and climatic change on rapid timescales. Lake modeling and lake core stratigraphies are complementary tools for exploration of how lakes and their biota respond to environmental or climatic perturbations. In one modeling approach for exploring these issues, a simple hydro-climatological lake model was developed that classifies lake sensitivity to climatic perturbations based upon lake area, catchment area, …
Evolution Of The Cretaceous Calcareous Nanofossil Genus Eiffellithus And Its Biostratigraphic Significance, Jamie L. Shamrock, David K. Watkins
Evolution Of The Cretaceous Calcareous Nanofossil Genus Eiffellithus And Its Biostratigraphic Significance, Jamie L. Shamrock, David K. Watkins
Department of Earth and Atmospheric Sciences: Faculty Publications
The calcareous nanofossil genus Eiffellithus is an important taxon of mid- to Upper Cretaceous marine sediments in biostratigraphy and paleoceanography. The definition of species within Eiffellithus have been both broadly interpreted and variably applied by nanofossil workers. This is particularly true for the Eiffellithus eximius plexus. While the taxonomy of mid-Cretaceous Eiffellithus species has recently been well-defined, the remaining 35 m.y. history of the genus has not been closely examined. Our investigation of Cenomanian to Maastrichtian sediments from the Western Interior Seaway, Gulf of Mexico, and Western Atlantic gives rise to six new species of Eiffellithus that can be reliably …
Pilot Study: The Nature And Thickness Of The Unsaturated Zone And Delineation Of Confined Aquifers, Sue Olafsen Lackey, Les Howard
Pilot Study: The Nature And Thickness Of The Unsaturated Zone And Delineation Of Confined Aquifers, Sue Olafsen Lackey, Les Howard
Conservation and Survey Division: Faculty and Staff Publications
No abstract provided.
Nebraska Statewide Groundwater-Level Monitoring Report 2009, Jesse T. Korus Dr., Mark E. Burbach
Nebraska Statewide Groundwater-Level Monitoring Report 2009, Jesse T. Korus Dr., Mark E. Burbach
Conservation and Survey Division: Faculty and Staff Publications
No abstract provided.
Possible Sources Of Archaeological Maize Found In Chaco Canyon And Aztec Ruin, New Mexico, Larry Benson, J. R. Stein, H. E. Taylor
Possible Sources Of Archaeological Maize Found In Chaco Canyon And Aztec Ruin, New Mexico, Larry Benson, J. R. Stein, H. E. Taylor
United States Geological Survey: Staff Publications
Maize played a major role in Chaco’s interaction with outlying communities in the southern Colorado Plateau. This paper seeks to determine where archaeological corn cobs brought to Chaco Canyon were grown. Strontium-isotope and trace-metal ratios of 180 soil-water and 18 surface-water sites in the Southern Colorado Plateau have revealed possible source areas for some of 37 archaeological corn cobs from Chaco Canyon and 10 archaeological corn cobs from Aztec Ruin, New Mexico. The most probable source areas for cobs that predate the middle-12th-century drought include several Upper Rio Chaco sites (not including Chaco Canyon). There are many potential source areas …
A Robust, Multisite Holocene History Of Drift Ice Off Northern Iceland: Implications For North Atlantic Climate, John T. Andrews, Dennis Darby, Dennis Eberle, Anne E. Jennings, Matthias Moros, Astrid Ogilvie
A Robust, Multisite Holocene History Of Drift Ice Off Northern Iceland: Implications For North Atlantic Climate, John T. Andrews, Dennis Darby, Dennis Eberle, Anne E. Jennings, Matthias Moros, Astrid Ogilvie
United States Geological Survey: Staff Publications
An important indicator of Holocene climate change is provided by evidence for variations in the extent of drift ice. A proxy for drift ice in Iceland waters is provided by the presence of quartz. Quantitative xray diffraction analysis of the < 2 mm sediment fraction was undertaken on 16 cores from around Iceland. The quartz weight (wt.)% estimates from each core were integrated into 250-yr intervals between −0.05 and 11.7 cal. ka BP. Median quartz wt.% varied between 0.2 and 3.4 and maximum values ranged between 2.8 and 11.8 wt.%. High values were attained in the early Holocene and minimum values were reached 6–7 cal. ka BP. Quartz wt.% then rose steadily during the late Holocene. Our data exhibit no correlation with counts on haematite-stained quartz (HSQ) grains from VM129-191 west of Ireland casting doubt on the ice-transport origin. A pilot study on the provenance of Fe oxide grains in two cores that cover the last 1.3 and 6.1 cal. ka BP indicated a large fraction of the grains between 1 and 6 cal. ka BP were from either Icelandic or presently unsampled sources. However, there was a dramatic increase in Canadian and Russian sources from the Arctic Ocean ~1 cal. ka BP. These data may indicate the beginning of an Arctic Oscillation-like climate mode.
History Of Wildlife Toxicology, Barnett A. Rattner
History Of Wildlife Toxicology, Barnett A. Rattner
United States Geological Survey: Staff Publications
The field of wildlife toxicology can be traced to
the late nineteenth and early twentieth centuries. Initial
reports included unintentional poisoning of birds from
ingestion of spent lead shot and predator control agents,
alkali poisoning of waterbirds, and die-offs from maritime
oil spills. With the advent of synthetic pesticides in the
1930s and 1940s, effects of DDT and other pesticides were
investigated in free-ranging and captive wildlife. In
response to research findings in the US and UK, and the
publication of Silent Spring in 1962, public debate on the
hazards of pollutants arose and national contaminant
monitoring programs were initiated. …
Climate Trends Of The North American Prairie Pothole Region 1906–2000, Bruce Millett, W. Carter Johnson, Glenn Guntenspergen
Climate Trends Of The North American Prairie Pothole Region 1906–2000, Bruce Millett, W. Carter Johnson, Glenn Guntenspergen
United States Geological Survey: Staff Publications
The Prairie Pothole Region (PPR) is unique to North America. Its millions of wetlands and abundant ecosystem goods and services are highly sensitive to wide variations of temperature and precipitation in time and space characteristic of a strongly continental climate. Precipitation and temperature gradients across the PPR are orthogonal to each other. Precipitation nearly triples from west to east from approximately 300 mm/year to 900 mm/year, while mean annual temperature ranges from approximately 1°C in the north to nearly 10°C in the south. Twentieth-century weather records for 18 PPR weather stations representing 6 ecoregions revealed several trends. The climate generally …
Climate Trends Of The North American Prairie Pothole Region 1906–2000, Bruce Millett, W. Carter Johnson, Glenn R. Guntenspergen
Climate Trends Of The North American Prairie Pothole Region 1906–2000, Bruce Millett, W. Carter Johnson, Glenn R. Guntenspergen
United States Geological Survey: Staff Publications
The Prairie Pothole Region (PPR) is unique to North America. Its millions of wetlands and abundant ecosystem goods and services are highly sensitive to wide variations of temperature and precipitation in time and space characteristic of a strongly continental climate. Precipitation and temperature gradients across the PPR are orthogonal to each other. Precipitation nearly triples from west to east from approximately 300 mm/year to 900 mm/year, while mean annual temperature ranges from approximately 1◦C in the north to nearly 10◦C in the south. Twentieth-century weather records for 18 PPR weather stations representing 6 ecoregions revealed several trends. The climate generally …
California Drought, An Update April 2008, Baryohay Davidoff, Fawzi Karajeh, Dean Reynolds, Eric Senter, John Woodling
California Drought, An Update April 2008, Baryohay Davidoff, Fawzi Karajeh, Dean Reynolds, Eric Senter, John Woodling
United States Geological Survey: Staff Publications
TABLE OF CONTENTS
CHAPTER 1. RECENT HYDROLOGIC CONDITIONS AND IMPACTS
Introduction....................................................... 1
Water Year 2007 .................................................. 1
Drought in the Colorado River Basin ..................................................... 5
Drought and Dry Conditions in the Early 2000s .................................... 7
The 2001 Klamath Basin Drought Emergency ............................... 11
CHAPTER 2. PROGRAMMATIC AND INSTITUTIONAL UPDATES
The San Francisco Bay-Sacramento/San Joaquin River Delta.................................................................. 15
The Colorado River .................................................................... 16
State Financial Assistance to Local Agencies.................................... 17
Urban Water Management Planning ................................................... 20
Water Transfers .............................................................................. 20
Small Water Systems and Drought Preparedness ................................. 21
Pamphlet To Accompany Geologic Map Gmc-34: Geologic Map Of The O’Neill 1º X 2º Quadrangle, Nebraska, With Configuration Maps Of Surfaces Of Formations, Robert F. Diffendal Jr., Michael R. Voorhies, E. Jane Voorhies, H. E. Lagarry, C. L. Timperley, M. E. Perkins
Pamphlet To Accompany Geologic Map Gmc-34: Geologic Map Of The O’Neill 1º X 2º Quadrangle, Nebraska, With Configuration Maps Of Surfaces Of Formations, Robert F. Diffendal Jr., Michael R. Voorhies, E. Jane Voorhies, H. E. Lagarry, C. L. Timperley, M. E. Perkins
Robert F. Diffendal, Jr., Publications
This map is necessarily generalized. It is based primarily on data from 7.5’ surficial geologic quadrangle maps of the map area prepared by the authors principally from 1991 to 2000, from Voorhies (unpublished data, 1974), as well as data from test-hole drilling done across the quadrangle by the Conservation and Survey Division, University of Nebraska, and its cooperators over many years since the 1930s. For more detailed information, consult the geologic data files of the Conservation and Survey Division, School of Natural Resources, University of Nebraska-Lincoln. The quadrangle is mostly covered by vegetation and Holocene sediments. Limited good exposures of …
Introgression And Dispersal Among Spotted Owl (Strix Occidentalis) Subspecies, W. Chris Funk, Eric D. Forsman, Thomas D. Mullins, Susan M. Haig
Introgression And Dispersal Among Spotted Owl (Strix Occidentalis) Subspecies, W. Chris Funk, Eric D. Forsman, Thomas D. Mullins, Susan M. Haig
United States Geological Survey: Staff Publications
Population genetics plays an increasingly important role in the conservation and management of declining species, particularly for defining taxonomic units. Subspecies are recognized by several conservation organizations and countries and receive legal protection under the US Endangered Species Act (ESA). Two subspecies of spotted owls, northern (Strix occidentalis caurina) and Mexican (S. o. lucida) spotted owls, are ESA-listed as threatened, but the California (S. o. occidentalis) spotted owl is not listed. Thus, determining the boundaries of these subspecies is critical for effective enforcement of the ESA. We tested the validity of previously recognized spotted …