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Carbon Storage And Sequestration By Trees In Urban And Community Areas Of The United States, David J. Nowak, Eric J. Greenfield, Robert E. Hoehn, Elizabeth Lapoint 2013 United States Department of Agriculture, Forest Service

Carbon Storage And Sequestration By Trees In Urban And Community Areas Of The United States, David J. Nowak, Eric J. Greenfield, Robert E. Hoehn, Elizabeth Lapoint

United States Department of Agriculture, Forest Service / University of Nebraska-Lincoln: Faculty Publications

Carbon storage and sequestration by urban trees in the United States was quantified to assess the magnitude and role of urban forests in relation to climate change. Urban tree field data from 28 cities and 6 states were used to determine the average carbon density per unit of tree cover. These data were applied to statewide urban tree cover measurements to determine total urban forest carbon storage and annual sequestration by state and nationally. Urban whole tree carbon storage densities average 7.69 kg C m‒2 of tree cover and sequestration densities average 0.28 kg C m‒2 of tree …


Mutation From Arginine To Lysine At The Position 189 Of Hemagglutinin Contributes To The Antigenic Drift In H3n2 Swine Influenza Viruses, Jianqiang Ye, Yifei Xu, Jillian Harris, Hailiang Sun, Andrew S. Bowman, Fred L. Cunningham, Carol Cardona, Kyoungjin J. Yoon, Richard D. Slemons, Xiu-Feng Wan 2013 Mississippi State University

Mutation From Arginine To Lysine At The Position 189 Of Hemagglutinin Contributes To The Antigenic Drift In H3n2 Swine Influenza Viruses, Jianqiang Ye, Yifei Xu, Jillian Harris, Hailiang Sun, Andrew S. Bowman, Fred L. Cunningham, Carol Cardona, Kyoungjin J. Yoon, Richard D. Slemons, Xiu-Feng Wan

United States Department of Agriculture Wildlife Services: Staff Publications

Two distinct antigenic clusters were previously identified among the H3N2 swine influenza A viruses (IAVs) and were designated H3N2SIV-alpha and H3N2SIV-beta (Feng et al., 2013. Journal of Virology 87(13), 7655–7667). A consistent mutation was observed at the position 189 of hemagglutinin (R189K) between H3N2SIV-alpha and H3N2SIV-beta fair isolates. To evaluate the contribution of R189K mutation to the antigenic drift from H3N2SIV-alpha to H3N2SIV-beta, four reassortant viruses with189R or189K were generated. The antigenic cartography demonstrated that the R189K mutation in the hemagglutinin of H3N2IAV contributed to the antigenicdrift, separating these viruses into H3N2SIV-alpha to H3N2SIV- beta. This R189K mutation was also …


The Floodplain Food Web Mosaic: A Study Of Its Importance To Salmon And Steelhead With Implications For Their Recovery, J. Ryan Bellmore, Colden V. Baxter, Kyle Martens, Patrick J. Connolly 2013 U.S. Geological Survey

The Floodplain Food Web Mosaic: A Study Of Its Importance To Salmon And Steelhead With Implications For Their Recovery, J. Ryan Bellmore, Colden V. Baxter, Kyle Martens, Patrick J. Connolly

United States Geological Survey: Staff Publications

Although numerous studies have attempted to place species of interest within the context of food webs, such efforts have generally occurred at small scales or disregard potentially important spatial heterogeneity. If food web approaches are to be employed to manage species, studies are needed that evaluate the multiple habitats and associated webs of interactions in which these species participate. Here, we quantify the food webs that sustain rearing salmon and steelhead within a floodplain landscape of the Methow River, Washington, USA, a location where restoration has been proposed to restore side channels in an attempt to recover anadromous fishes. We …


Predictive Models For Escherichia Coli Concentrations At Inland Lake Beaches And Relationship Of Model Variables To Pathogen Detection, Donna S. Francy, Erin A. Stelzer, Joseph W. Duris, Amie M. G. Brady, John H. Harrison, Heather E. Johnson, Michael W. Ware 2013 U.S. Geological Survey

Predictive Models For Escherichia Coli Concentrations At Inland Lake Beaches And Relationship Of Model Variables To Pathogen Detection, Donna S. Francy, Erin A. Stelzer, Joseph W. Duris, Amie M. G. Brady, John H. Harrison, Heather E. Johnson, Michael W. Ware

United States Geological Survey: Staff Publications

Predictive models, based on environmental and water quality variables, have been used to improve the timeliness and accuracy of recreational water quality assessments, but their effectiveness has not been studied in inland waters. Sampling at eight inland recreational lakes in Ohio was done in order to investigate using predictive models for Escherichia coli and to understand the links between E. coli concentrations, predictive variables, and pathogens. Based upon results from 21 beach sites, models were developed for 13 sites, and the most predictive variables were rainfall, wind direction and speed, turbidity, and water temperature. Models were not developed at sites …


The Malthusian–Darwinian Dynamic And The Trajectory Of Civilization, Jeffrey C. Nekola, Craig D. Allen, James H. Brown, Joseph R. Burger, Ana D. Davidson, Trevor S. Fristoe, Marcus J. Hamilton, Sean T. Hammond, Astrid Kodric-Brown, Norman Mercado-Silva, Jordan G. Okie 2013 University of New Mexico - Main Campus

The Malthusian–Darwinian Dynamic And The Trajectory Of Civilization, Jeffrey C. Nekola, Craig D. Allen, James H. Brown, Joseph R. Burger, Ana D. Davidson, Trevor S. Fristoe, Marcus J. Hamilton, Sean T. Hammond, Astrid Kodric-Brown, Norman Mercado-Silva, Jordan G. Okie

United States Geological Survey: Staff Publications

Two interacting forces influence all populations: the Malthusian dynamic of exponential growth until resource limits are reached, and the Darwinian dynamic of innovation and adaptation to circumvent these limits through biological and/or cultural evolution. The specific manifestations of these forces in modern human society provide an important context for determining how humans can establish a sustainable relationship with the finite Earth.


Reproductive Health Of Yellow Perch Perca Flavescens In Selected Tributaries Of The Chesapeake Bay, Vicki S. Blazer, Alfred E. Pinkney, Jill A. Jenkins, Luke R. Iwanowicz, Steven Minkkinen, Rassa O. Draugelis-Dale, James H. Uphoff 2013 U.S. Geological Survey

Reproductive Health Of Yellow Perch Perca Flavescens In Selected Tributaries Of The Chesapeake Bay, Vicki S. Blazer, Alfred E. Pinkney, Jill A. Jenkins, Luke R. Iwanowicz, Steven Minkkinen, Rassa O. Draugelis-Dale, James H. Uphoff

United States Geological Survey: Staff Publications

Reduced recruitment of yellow perch has been noted for a number of years in certain urbanized watersheds (South and Severn Rivers) of the Chesapeake Bay. Other rapidly developing watersheds such as Mattawoman Creek are more recently showing evidence of reduced recruitment of anadromous fishes. In this study, we used a battery of biomarkers to better document the reproductive health of adult yellow perch collected during spring spawning in 2007–2009. Perch were collected in the South and Severn Rivers, Mattawoman Creek and the less developed Choptank and Allen's Fresh watersheds for comparison. Gonadosomatic indices, plasma reproductive hormone concentrations, plasma vitellogenin concentrations …


Performance Of Human Fecal Anaerobe-Associated Pcr-Based Assays In A Multi-Laboratory Method Evaluation Study, Blythe A. Layton, Yiping Cao, Darcy L. Ebentier, Kaitlyn Hanley, Elisenda Balleste, Joao Brandao, Muruleedhara Byappanahalli, Reagan Converse, Andreas H. Farnleitner, Jennifer Gentry-Shields, Maribeth L. Gidley, Michele Gourmelon, Chang Soo Lee, Jiyoung Lee, Solen Lozach, Tania Madi, Wim G. Meijer, Rachel Noble, Lindsay Peed, Georg H. Reischer, Raquel Rodrigues, Joan B. Rose, Alexander Schriewer, Chris Sinigalliano, Sangeetha Srinivasan, Jill Stewart, Laurie C. Van De Werfhorst, Dan Wang, Richard Whitman, Stefan Wuertz, Jenny Jay, Patricia A. Holden, Alexandria B. Boehm, Orin Shanks, John F. Griffith 2013 Southern California Coastal Water Research Project

Performance Of Human Fecal Anaerobe-Associated Pcr-Based Assays In A Multi-Laboratory Method Evaluation Study, Blythe A. Layton, Yiping Cao, Darcy L. Ebentier, Kaitlyn Hanley, Elisenda Balleste, Joao Brandao, Muruleedhara Byappanahalli, Reagan Converse, Andreas H. Farnleitner, Jennifer Gentry-Shields, Maribeth L. Gidley, Michele Gourmelon, Chang Soo Lee, Jiyoung Lee, Solen Lozach, Tania Madi, Wim G. Meijer, Rachel Noble, Lindsay Peed, Georg H. Reischer, Raquel Rodrigues, Joan B. Rose, Alexander Schriewer, Chris Sinigalliano, Sangeetha Srinivasan, Jill Stewart, Laurie C. Van De Werfhorst, Dan Wang, Richard Whitman, Stefan Wuertz, Jenny Jay, Patricia A. Holden, Alexandria B. Boehm, Orin Shanks, John F. Griffith

United States Geological Survey: Staff Publications

A number of PCR-based methods for detecting human fecal material in environmental waters have been developed over the past decade, but these methods have rarely received independent comparative testing in large multi-laboratory studies. Here, we evaluated ten of these methods (BacH, BacHum-UCD, Bacteroides thetaiotaomicron (BtH), BsteriF1, gyrB, HF183 endpoint, HF183 SYBR, HF183 Taqman®, HumM2, and Methanobrevibacter smithii nifH (Mnif)) using 64 blind samples prepared in one laboratory. The blind samples contained either one or two fecal sources from human, wastewater or non-human sources. The assay results were assessed for presence/absence of the human markers and also quantitatively while …


Human-Caused Mortality Influences Spatial Population Dynamics: Pumas In Landscapes With Varying Mortality Risks, Jesse R. Newby, L. Scott Mills, Toni K. Ruth, Daniel H. Pletscher, Michael S. Mitchell, Howard B. Quigley, Kerry M. Murphy, Rich DeSimone 2013 University of Montana - Missoula

Human-Caused Mortality Influences Spatial Population Dynamics: Pumas In Landscapes With Varying Mortality Risks, Jesse R. Newby, L. Scott Mills, Toni K. Ruth, Daniel H. Pletscher, Michael S. Mitchell, Howard B. Quigley, Kerry M. Murphy, Rich Desimone

United States Geological Survey: Staff Publications

An understanding of how stressors affect dispersal attributes and the contribution of local populations to multi-population dynamics are of immediate value to basic and applied ecology. Puma (Puma concolor) populations are expected to be influenced by inter-population movements and susceptible to human induced source–sink dynamics. Using long-term datasets we quantified the contribution of two puma populations to operationally define them as sources or sinks. The puma population in the Northern Greater Yellowstone Ecosystem (NGYE) was largely insulated from human-induced mortality by Yellowstone National Park. Pumas in the western Montana Garnet Mountain system were exposed to greater human-induced mortality, …


A Causal Examination Of The Effects Of Confounding Factors On Multimetric Indices, Donald R. Schoolmaster Jr., James B. Grace, E. William Schweiger, Brian R. Mitchell, Glenn R. Guntenspergen 2013 Five Rivers Services

A Causal Examination Of The Effects Of Confounding Factors On Multimetric Indices, Donald R. Schoolmaster Jr., James B. Grace, E. William Schweiger, Brian R. Mitchell, Glenn R. Guntenspergen

United States Geological Survey: Staff Publications

The development of multimetric indices (MMIs) as a means of providing integrative measures of ecosystem condition is becoming widespread. An increasingly recognized problem for the interpretability of MMIs is controlling for the potentially confounding influences of environmental covariates. Most common approaches to handling covariates are based on simple notions of statistical control, leaving the causal implications of covariates and their adjustment unstated. In this paper, we use graphical models to examine some of the potential impacts of environmental covariates on the observed signals between human disturbance and potential response metrics. Using simulations based on various causal networks, we show how …


An Algorithmic And Information-Theoretic Approach To Multimetric Index Construction, Donald R. Schoolmaster Jr., James B. Grace, E. William Schweiger, Glenn R. Guntenspergen, Brian R. Mitchell, Kathryn M. Miller, Amanda M. Little 2013 Five Rivers Services

An Algorithmic And Information-Theoretic Approach To Multimetric Index Construction, Donald R. Schoolmaster Jr., James B. Grace, E. William Schweiger, Glenn R. Guntenspergen, Brian R. Mitchell, Kathryn M. Miller, Amanda M. Little

United States Geological Survey: Staff Publications

The use of multimetric indices (MMIs), such as the widely used index of biological integrity (IBI), to measure, track, summarize and infer the overall impact of human disturbance on biological communities has been steadily growing in recent years. Initially, MMIs were developed for aquatic communities using preselected biological metrics as indicators of system integrity. As interest in these bioassessment tools has grown, so have the types of biological systems to which they are applied. For many ecosystem types the appropriate biological metrics to use as measures of biological integrity are not known a priori. As a result, a variety of …


Extending Airborne Electromagnetic Surveys For Regional Active Layer And Permafrost Mapping With Remote Sensing And Ancillary Data, Yukon Flats Ecoregion, Central Alaska, Neal J. Pastick, M. Torre Jorgenson, Bruce K. Wylie, Burke J. Minsley, Lei Ji, Michelle A. Walvoord, Bruce D. Smith, Jared D. Abraham, Joshua R. Rose 2013 Stinger Ghaffarian Technologies, Inc.

Extending Airborne Electromagnetic Surveys For Regional Active Layer And Permafrost Mapping With Remote Sensing And Ancillary Data, Yukon Flats Ecoregion, Central Alaska, Neal J. Pastick, M. Torre Jorgenson, Bruce K. Wylie, Burke J. Minsley, Lei Ji, Michelle A. Walvoord, Bruce D. Smith, Jared D. Abraham, Joshua R. Rose

United States Geological Survey: Staff Publications

Machine-learning regression tree models were used to extrapolate airborne electromagnetic resistivity data collected along flight lines in the Yukon Flats Ecoregion, central Alaska, for regional mapping of permafrost. This method of extrapolation (r = 0.86) used subsurface resistivity, Landsat Thematic Mapper (TM) at-sensor reflectance, thermal, TM-derived spectral indices, digital elevation models and other relevant spatial data to estimate near-surface (0–2.6-m depth) resistivity at 30-m resolution. A piecewise regression model (r = 0.82) and a presence/absence decision tree classification (accuracy of 87%) were used to estimate active-layer thickness (ALT) (< 101 cm) and the probability of near-surface (up to 123-cm depth) permafrost occurrence from field data, modelled near-surface (0–2.6m) resistivity, and other relevant remote sensing and map data. At site scale, the predicted ALTs were similar to those previously observed for different vegetation types. At the landscape scale, the predicted ALTs tended to be thinner on higher-elevation loess deposits than on low-lying alluvial and sand sheet deposits of the Yukon Flats. The ALT and permafrost maps provide a baseline for future permafrost monitoring, serve as inputs for modelling hydrological and carbon cycles at local to regional scales, and offer insight into the ALT response to fire and thaw processes. Published 2013. This article is a U.S. Government work and is in the public domain in the USA.


A Review Of Environmental Impacts Of Salts From Produced Waters On Aquatic Resources, Aida M. Farag, David D. Harper 2013 U.S. Geological Survey

A Review Of Environmental Impacts Of Salts From Produced Waters On Aquatic Resources, Aida M. Farag, David D. Harper

United States Geological Survey: Staff Publications

Salts are frequently amajor constituent ofwastewaters produced during oil and gas production. These produced waters or brines must be treated and/or disposed and provide a daily challenge for operators and resourcemanagers. Some elements of salts are regulated with water quality criteria established for the protection of aquatic wildlife, e.g. chloride (Cl), which has an acute standard of 860 mg/L and a chronic standard of 230 mg/L. However, data for establishing such standards has only recently been studied for other components of produced water, such as bicarbonate (HCO3 ), which has acute median lethal concentrations (LC50s) ranging from …


Loess Origin, Transport, And Deposition Over The Past 10,000 Years, Wrangell-St. Elias National Park, Alaska, Daniel R. Muhs, James R. Budahn, John P. McGeehin, E. Arthur Bettis III, Gary Skipp, James B. Paces, Elisabeth A. Wheeler 2013 U.S. Geological Survey

Loess Origin, Transport, And Deposition Over The Past 10,000 Years, Wrangell-St. Elias National Park, Alaska, Daniel R. Muhs, James R. Budahn, John P. Mcgeehin, E. Arthur Bettis Iii, Gary Skipp, James B. Paces, Elisabeth A. Wheeler

United States Geological Survey: Staff Publications

Contemporary glaciogenic dust has not received much attention, because most research has been on glaciogenic dust of the last glacial period or non-glaciogenic dust of the present interglacial period. Nevertheless, dust from modern glaciogenic sources may be important for Fe inputs to primary producers in the ocean. Adjacent to the subarctic Pacific Ocean, we studied a loess section near Chitina, Alaska along the Copper River in Wrangell-St. Elias National Park, where dust has been accumulating over the past ~10,000 years. Mass accumulation rates for the fine-grained (<20 >µm) fraction of this loess section are among the highest reported for the …


Chronology And Provenance Of Last-Glacial (Peoria) Loess In Western Iowa And Paleoclimatic Implications, Daniel R. Muhs, E. Arthur Bettis III, Helen M. Roberts, Stephen S. Harlan, James B. Paces, Richard L. Reynolds 2013 U.S. Geological Survey

Chronology And Provenance Of Last-Glacial (Peoria) Loess In Western Iowa And Paleoclimatic Implications, Daniel R. Muhs, E. Arthur Bettis Iii, Helen M. Roberts, Stephen S. Harlan, James B. Paces, Richard L. Reynolds

United States Geological Survey: Staff Publications

Geologic archives show that the Earth was dustier during the last glacial period. One model suggests that increased gustiness (stronger, more frequent winds) enhanced dustiness. We tested this at Loveland, Iowa, one of the thickest deposits of last-glacial-age (Peoria) loess in the world. Based on K/Rb and Ba/Rb, loess was derived not only from glaciogenic sources of the Missouri River, but also distal loess from non-glacial sources in Nebraska. Optically stimulated luminescence (OSL) ages provide the first detailed chronology of Peoria Loess at Loveland. Deposition began after ~27 ka and continued until ~17 ka. OSL ages also indicate that mass …


Origin Of The Sinai-Negev Erg, Egypt And Israel: Mineralogical And Geochemical Evidence For The Importance Of The Nile And Sea Level History, Daniel R. Muhs, Joel Roskin, Haim Tsoar, Gary Skipp, James Budahn, Amihai Sneh, Naomi Porat, Jean-Daniel Stanley, Itzhak Katra, Dan G. Blumberg 2013 U.S. Geological Survey

Origin Of The Sinai-Negev Erg, Egypt And Israel: Mineralogical And Geochemical Evidence For The Importance Of The Nile And Sea Level History, Daniel R. Muhs, Joel Roskin, Haim Tsoar, Gary Skipp, James Budahn, Amihai Sneh, Naomi Porat, Jean-Daniel Stanley, Itzhak Katra, Dan G. Blumberg

United States Geological Survey: Staff Publications

The Sinai-Negev erg occupies an area of 13,000 km2 in the deserts of Egypt and Israel. Aeolian sand of this erg has been proposed to be derived from the Nile Delta, but empirical data supporting this view are lacking. An alternative source sediment is sand from the large Wadi El Arish drainage system in central and northern Sinai. Mineralogy of the Negev and Sinai dunes shows that they are high in quartz, with much smaller amounts of K-feldspar and plagioclase. Both Nile Delta sands and Sinai wadi sands, upstream of the dunes, also have high amounts of quartz relative …


Toxic Exposure Of Songbirds To Lead In The Southeast Missouri Lead Mining District, W. Nelson Beyer, J. Christian Franson, John B. French, Thomas May, Barnett A. Rattner, Valerie I. Shearn-Bochsler, Sarah E. Warner, John Weber, David Mosby 2013 USGS Patuxent Wildlife Research Center

Toxic Exposure Of Songbirds To Lead In The Southeast Missouri Lead Mining District, W. Nelson Beyer, J. Christian Franson, John B. French, Thomas May, Barnett A. Rattner, Valerie I. Shearn-Bochsler, Sarah E. Warner, John Weber, David Mosby

United States Geological Survey: Staff Publications

Mining and smelting in the Southeast Missouri Lead Mining District has caused widespread contamination of soils with lead (Pb) and other metals. Soils from three study sites sampled in the district contained from approximately 1,000–3,200 mg Pb/kg. Analyses of earthworms [33–4,600 mg Pb/kg dry weight (dw)] collected in the district showed likely high Pb exposure of songbirds preying on soil organisms. Mean tissue Pb concentrations in songbirds collected from the contaminated sites were greater (p < 0.05) than those in songbirds from reference sites by factors of 8 in blood, 13 in liver, and 23 in kidney. Ranges of Pb concentrations in livers (mg Pb/kg dw) were as follows: northern cardinal (Cardinalis cardinalis) = 0.11–3.0 (reference) and 1.3–30 (contaminated) and American robin (Turdus migratorius) = 0.43–8.5 (reference) and 7.6–72 (contaminated). Of 34 …


Comparative Embryotoxicity Of A Pentabrominated Diphenyl Ether Mixture To Common Terns (Sterna Hirundo) And American Kestrels (Falco Sparverius), Barnett A. Rattner, Rebecca S. Lazarus, Gary H. Heinz, Natalie K. Karouna-Renier, Sandra L. Schultz, Robert C. Hale 2013 United States Geological Survey

Comparative Embryotoxicity Of A Pentabrominated Diphenyl Ether Mixture To Common Terns (Sterna Hirundo) And American Kestrels (Falco Sparverius), Barnett A. Rattner, Rebecca S. Lazarus, Gary H. Heinz, Natalie K. Karouna-Renier, Sandra L. Schultz, Robert C. Hale

United States Geological Survey: Staff Publications

Concentrations of polybrominated diphenyl ethers (PBDEs) in Forster’s tern (Sterna forsteri) eggs from San Francisco Bay have been reported to range up to 63 µg g-1 lipid weight. This value exceeds the lowest-observed-adverse-effect level (1.8 µg g-1 egg wet weight; ~32 µg g-1 lipid weight) reported in an embryotoxicity study with American kestrels (Falco sparverius). As a surrogate for Forster’s terns, common tern (Sterna hirundo) eggs were treated by air cell injection with corn oil vehicle (control) or a commercial penta-BDE formulation (DE-71) at nominal concentrations of 0.2, 2, and 20 µg g …


A Global Standard For Monitoring Coastal Wetland Vulnerability To Accelerated Sea-Level Rise, Edward L. Webb, Daniel A. Friess, Ken W. Krauss, Donald R. Cahoon, Glenn R. Guntenspergen, Jacob Phelps 2013 National University of Singapore

A Global Standard For Monitoring Coastal Wetland Vulnerability To Accelerated Sea-Level Rise, Edward L. Webb, Daniel A. Friess, Ken W. Krauss, Donald R. Cahoon, Glenn R. Guntenspergen, Jacob Phelps

United States Geological Survey: Staff Publications

Sea-level rise threatens coastal salt-marshes and mangrove forests around the world, and a key determinant of coastal wetland vulnerability is whether its surface elevation can keep pace with rising sea level. Globally, a large data gap exists because wetland surface and shallow subsurface processes remain unaccounted for by traditional vulnerability assessments using tide gauges. Moreover, those processes vary substantially across wetlands, so modelling platforms require relevant local data. The low-cost, simple, high-precision rod surface-elevation table–marker horizon (RSET-MH) method fills this critical data gap, can be paired with spatial data sets and modelling and is financially and technically accessible to every …


Use Of Nmr Logging To Obtain Estimates Of Hydraulic Conductivity In The High Plains Aquifer, Nebraska, Usa, Katherine Dlubac, Rosemary Knight, Yi-Qiao Song, Nate Bachman, Ben Grau, Jim Cannia, John Williams 2013 Stanford University

Use Of Nmr Logging To Obtain Estimates Of Hydraulic Conductivity In The High Plains Aquifer, Nebraska, Usa, Katherine Dlubac, Rosemary Knight, Yi-Qiao Song, Nate Bachman, Ben Grau, Jim Cannia, John Williams

United States Geological Survey: Staff Publications

Hydraulic conductivity (K) is one of the most important parameters of interest in groundwater applications because it quantifies the ease with which water can flow through an aquifer material. Hydraulic conductivity is typically measured by conducting aquifer tests or wellbore flow (WBF) logging. Of interest in our research is the use of proton nuclear magnetic resonance (NMR) logging to obtain information about water-filled porosity and pore space geometry, the combination of which can be used to estimate K. In this study, we acquired a suite of advanced geophysical logs, aquifer tests, WBF logs, and sidewall cores at the …


Spatially Explicit Models For Inference About Density In Unmarked Or Partially Marked Populations, Richard B. Chandler, J. Andrew Royle 2013 USGS Patuxent Wildlife Research Center & the North American Breeding Bird Survey Program

Spatially Explicit Models For Inference About Density In Unmarked Or Partially Marked Populations, Richard B. Chandler, J. Andrew Royle

United States Geological Survey: Staff Publications

Recently developed spatial capture-recapture (SCR) models represent a major advance over traditional capture-recapture (CR) models because they yield explicit estimates of animal density instead of population size within an unknown area. Furthermore, unlike non-spatial CR methods, SCR models account for heterogeneity in capture probability arising from the juxtaposition of animal activity centers and sample locations. Although the utility of SCR methods is gaining recognition, the requirement that all individuals can be uniquely identified excludes their use in many contexts. In this paper, we develop models for situations in which individual recognition is not possible, thereby allowing SCR concepts to be …


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