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2013

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Articles 481 - 510 of 541

Full-Text Articles in Oceanography and Atmospheric Sciences and Meteorology

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

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 …

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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 Jan 2013

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 …

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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 Jan 2013

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 …

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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 Jan 2013

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 …

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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 Jan 2013

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 …

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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 Jan 2013

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 …

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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 Jan 2013

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 …

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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 Jan 2013

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 …

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Spatially Explicit Models For Inference About Density In Unmarked Or Partially Marked Populations, Richard B. Chandler, J. Andrew Royle Jan 2013

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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The Geologic Records Of Dust In The Quaternary, Daniel R. Muhs Jan 2013

The Geologic Records Of Dust In The Quaternary, Daniel R. Muhs

United States Geological Survey: Staff Publications

Study of geologic records of dust composition, sources and deposition rates is important for understanding the role of dust in the overall planetary radiation balance, fertilization of organisms in the world’s oceans, nutrient additions to the terrestrial biosphere and soils, and for paleoclimatic reconstructions. Both glacial and non-glacial processes produce fine-grained particles that can be transported by the wind. Geologic records of dust flux occur in a number of depositional archives for sediments: (1) loess deposits; (2) lake sediments; (3) soils; (4) deep-ocean basins; and (5) ice sheets and smaller glaciers. These archives have several characteristics that make them highly …

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Analyzing Experimental Data And Model Parameters: Implications For Predictions Of Soa Using Chemical Transport Models, Kelley Barsanti, Annmarie G. Carlton, Serena H. Chung Jan 2013

Analyzing Experimental Data And Model Parameters: Implications For Predictions Of Soa Using Chemical Transport Models, Kelley Barsanti, Annmarie G. Carlton, Serena H. Chung

Civil and Environmental Engineering Faculty Publications and Presentations

Despite critical importance for air quality and climate predictions, accurate representation of secondary organic aerosol (SOA) formation remains elusive. An essential addition to the ongoing discussion of improving model predictions is an acknowledgement of the linkages between experimental conditions, parameter optimization and model output, as well as the linkage between empirically-derived partitioning parameters and the physicochemical properties of SOA they represent in models. In this work, a "best available" set of SOA modeling parameters is selected by comparing predicted SOA yields and mass concentrations with observed yields and mass concentrations from a comprehensive list of published smog chamber studies. Evaluated …

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Satellite-Based Estimates Of Antarctic Surface Meltwater Fluxes, Luke D. Trusel, Karen E. Frey, Sarah B. Das, Peter Kuipers Munneke, Michiel R. Van Den Broeke Jan 2013

Satellite-Based Estimates Of Antarctic Surface Meltwater Fluxes, Luke D. Trusel, Karen E. Frey, Sarah B. Das, Peter Kuipers Munneke, Michiel R. Van Den Broeke

Geography

This study generates novel satellite-derived estimates of Antarctic-wide annual (1999-2009) surface meltwater production using an empirical relationship between radar backscatter from the QuikSCAT (QSCAT) satellite and melt calculated from in situ energy balance observations. The resulting QSCAT-derived melt fluxes significantly agree with output from the regional climate model RACMO2.1 and with independent ground-based observations. The high-resolution (4.45 km) QSCAT-based melt fluxes uniquely detect interannually persistent and intense melt (>400 mm water equivalent (w.e.) year-1) on interior Larsen C Ice Shelf that is not simulated by RACMO2.1. This supports a growing understanding of the importance of a föhn effect in …

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Ice Sheet Record Of Recent Sea-Ice Behavior And Polynya Variability In The Amundsen Sea, West Antarctica, Alison S. Criscitiello, Sarah B. Das, Matthew J. Evans, Karen E. Frey, Howard Conway, Ian Joughin, Brooke Medley, Eric J. Steig Jan 2013

Ice Sheet Record Of Recent Sea-Ice Behavior And Polynya Variability In The Amundsen Sea, West Antarctica, Alison S. Criscitiello, Sarah B. Das, Matthew J. Evans, Karen E. Frey, Howard Conway, Ian Joughin, Brooke Medley, Eric J. Steig

Geography

[1] Our understanding of past sea-ice variability is limited by the short length of satellite and instrumental records. Proxy records can extend these observations but require further development and validation. We compare methanesulfonic acid (MSA) and chloride (Cl-) concentrations from a new firn core from coastal West Antarctica with satellite-derived observations of regional sea-ice concentration (SIC) in the Amundsen Sea (AS) to evaluate spatial and temporal correlations from 2002-2010. The high accumulation rate (∼39 g·cm-2·yr-1) provides monthly resolved records of MSA and Cl-, allowing detailed investigation of how regional SIC is recorded in the ice-sheet stratigraphy. Over the period 2002-2010 …

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Turbulent Collision-Coalescence In Maritime Shallow Convection, A. A. Wyszogrodzki, W.W. Grabowski, L. P. Wang, Orlando Ayala Jan 2013

Turbulent Collision-Coalescence In Maritime Shallow Convection, A. A. Wyszogrodzki, W.W. Grabowski, L. P. Wang, Orlando Ayala

Engineering Technology Faculty Publications

This paper discusses cloud simulations aiming at quantitative assessment of the effects of cloud turbulence on rain development in shallow ice-free convective clouds. Cloud fields from large-eddy simulations (LES) applying bin microphysics with the collection kernel enhanced by cloud turbulence are compared to those with the standard gravitational collection kernel. Simulations for a range of cloud condensation nuclei (CCN) concentrations are contrasted. Details on how the parameterized turbulent collection kernel is used in LES simulations are presented. Because of the disparity in spatial scales between the bottom-up numerical studies guiding the turbulent kernel development and the top-down LES simulations of …

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Terpene And Terpenoid Emissions And Secondary Organic Aerosol Production, Rosa M. Flores Jan 2013

Terpene And Terpenoid Emissions And Secondary Organic Aerosol Production, Rosa M. Flores

Dissertations, Master's Theses and Master's Reports - Open

Approximately 90% of fine aerosol in the Midwestern United States has a regional component with a sizable fraction attributed to secondary production of organic aerosol (SOA). The Ozark Forest is an important source of biogenic SOA precursors like isoprene (> 150 mg m-2 d-1), monoterpenes (10-40 mg m-2 d-1), and sesquiterpenes (10-40 mg m-2d-1). Anthropogenic sources include secondary sulfate and nitrate and biomass burning (51-60%), vehicle emissions (17-26%), and industrial emissions (16-18%). Vehicle emissions are an important source of volatile and vapor-phase, semivolatile aliphatic and aromatic hydrocarbons that are important …

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Investigations Of Cloud Microphysical Response To Mixing Using Digital Holography, Matthew Jacob Beals Jan 2013

Investigations Of Cloud Microphysical Response To Mixing Using Digital Holography, Matthew Jacob Beals

Dissertations, Master's Theses and Master's Reports - Open

Cloud edge mixing plays an important role in the life cycle and development of clouds. Entrainment of subsaturated air affects the cloud at the microscale, altering the number density and size distribution of its droplets. The resulting effect is determined by two timescales: the time required for the mixing event to complete, and the time required for the droplets to adjust to their new environment. If mixing is rapid, evaporation of droplets is uniform and said to be homogeneous in nature. In contrast, slow mixing (compared to the adjustment timescale) results in the droplets adjusting to the transient state of …

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Metr 200: Weather And Climate—A Peer Review Of Teaching Project Benchmark Portfolio, Matthew S. Van Den Broeke Jan 2013

Metr 200: Weather And Climate—A Peer Review Of Teaching Project Benchmark Portfolio, Matthew S. Van Den Broeke

UNL Faculty Course Portfolios

This benchmark portfolio is meant to be an assessment of how well the objectives of METR 200 (Weather and Climate) are being attained by students in several classifications of academic major. Students from a wide range of backgrounds enroll in this course as a general science elective, and for many, it will be the only science course taken in college. Thus, it is important that course material be sufficiently accessible for all students, while providing meaningful information which will be applicable by students of all backgrounds once they leave the course. In this portfolio, an analysis will be presented showing …

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Metr 323: Physical Meteorology—A Peer Review Of Teaching Project Benchmark Portfolio, Jun Wang Jan 2013

Metr 323: Physical Meteorology—A Peer Review Of Teaching Project Benchmark Portfolio, Jun Wang

UNL Faculty Course Portfolios

Hands-on out-door activities are added into a course that is designed to teach students atmospheric physics ranging form solar light transfer to cloud and precipitation formation in the atmosphere. Statistical analysis and anonymous survey are conducted to benchmark the improvement in students' learning. Results show that these hands-on activities increase the student's interest and understanding in the course materials, and also improve the overall students' satisfaction for the course.

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The Educational Training Of Storm Chasers And Storm Spotters In Relation To Geographical Dispersion Across The United States, Paul R. Zunkel Jan 2013

The Educational Training Of Storm Chasers And Storm Spotters In Relation To Geographical Dispersion Across The United States, Paul R. Zunkel

All Graduate Theses, Dissertations, and Other Capstone Projects

When severe weather strikes, storm chasers and storm spotters confirm that what forecasters and meteorologists are seeing on a radar screen is actually occurring in the field. While some documenters are classically trained (i.e. they have a background in atmospheric science and or meteorology attained from a 4 year university) many others are not. There are currently two organizations available for the weather enthusiast to be a part of, SKYWARN and SpotterNetwork. These organizations give weather enthusiasts a background knowledge into severe weather; however, many weather enthusiasts are not classically trained and most have not taken any formal education in …

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Uncertainties In Modelling Heterogeneous Chemistry And Arctic Ozone Depletion In The Winter 2009/2010, I. Wohltmann, T. Wegner, R. Müller, R. Lehmann, M. Rex, G. L. Manney, M. L. Santee, P. Bernath, O. Suminska-Ebersoldt Jan 2013

Uncertainties In Modelling Heterogeneous Chemistry And Arctic Ozone Depletion In The Winter 2009/2010, I. Wohltmann, T. Wegner, R. Müller, R. Lehmann, M. Rex, G. L. Manney, M. L. Santee, P. Bernath, O. Suminska-Ebersoldt

Chemistry & Biochemistry Faculty Publications

Stratospheric chemistry and denitrification are simulated for the Arctic winter 2009/2010 with the Lagrangian Chemistry and Transport Model ATLAS. A number of sensitivity runs is used to explore the impact of uncertainties in chlorine activation and denitrification on the model results. In particular, the efficiency of chlorine activation on different types of liquid aerosol versus activation on nitric acid trihydrate clouds is examined. Additionally, the impact of changes in reaction rate coefficients, in the particle number density of polar stratospheric clouds, in supersaturation, temperature or the extent of denitrification is investigated. Results are compared to satellite measurements of MLS and …

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Depositional History Of The Trinity-Tiger Shoals Region : A Transgressed Delta Complex Of The Middle Holocene Mississippi Delta, Clint Hoyt Edrington Jan 2013

Depositional History Of The Trinity-Tiger Shoals Region : A Transgressed Delta Complex Of The Middle Holocene Mississippi Delta, Clint Hoyt Edrington

LSU Doctoral Dissertations

The Holocene Mississippi River Delta is arguably the world’s most thoroughly researched deltaic system. However, much of this research has occurred predominantly within the present-day subaerial delta, whereas comparatively little research has been attempted downdip within the offshore, more difficult-to-reach parts. This study advances our understanding of the Holocene delta by examining deltaic sediments within the Trinity-Tiger Shoals Complex region, located ~ 30 – 40 km offshore of central Louisiana. Specifically, this study addresses two questions. Which delta complex prograded into this offshore region? Do the overlying transgressive deposits reflect that predicted by the prevailing transgressive depositional systems model? To …

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Reef Fish Demographics On Louisiana Artificial Reefs : The Effects Of Reef Size On Biomass Distribution And Foraging Dynamics, Kirsten A. Simonsen Jan 2013

Reef Fish Demographics On Louisiana Artificial Reefs : The Effects Of Reef Size On Biomass Distribution And Foraging Dynamics, Kirsten A. Simonsen

LSU Doctoral Dissertations

Understanding the role that habitat plays in the life history of reef-associated fishes is particularly significant given the dramatic increase in the number of artificial reefs deployed in coastal ecosystems over the past 50 years. In the Gulf of Mexico, the oil and gas industry has added a significant amount of structure to the Louisiana continental shelf, creating the largest de facto artificial reef deployment area in the world. Noting their usefulness as fish habitat, the Louisiana Artificial Reef Program was established to convert decommissioned platforms into artificial reefs. However, very little quantitative information exists on how these habitats affect …

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A History Of Place: Using Phytolith Analysis To Discern Holocene Vegetation Change On Sanak Island, Western Gulf Of Alaska, Cricket C. Wilbur Jan 2013

A History Of Place: Using Phytolith Analysis To Discern Holocene Vegetation Change On Sanak Island, Western Gulf Of Alaska, Cricket C. Wilbur

Antioch University Dissertations & Theses

This study investigated a terrestrial climate proxy, phytoliths, as a complimentary approach to documenting the dynamics of present and past vegetation on Sanak Island, the largest island in a small island group in the eastern Aleutian archipelago, and as a new basis by which to interpret Holocene environmental variability in Alaska. A phytolith reference collection was established from 59 selected plant species of maritime tundra belonging to 27 families. The grass species and a sedge species produced abundant phytolith forms whereas the majority of dicotyledons in this study were trace producers of phytoliths. A paleoenvironmental reconstruction from fossil phytoliths recovered …

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Combining Angular And Spatial Information From Multibeam Backscatter Data For Improved Unsupervised Acoustic Seabed Segmentation, Alexandre C. Schimel, Yuri Rzhanov, Luciano E. Fonseca, M Mayer, Dirk Immenga Jan 2013

Combining Angular And Spatial Information From Multibeam Backscatter Data For Improved Unsupervised Acoustic Seabed Segmentation, Alexandre C. Schimel, Yuri Rzhanov, Luciano E. Fonseca, M Mayer, Dirk Immenga

Center for Coastal and Ocean Mapping

No abstract provided.

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Seabed Classification For Trawlability Determined With A Multibeam Echo Sounder On Snakehead Bank In The Gulf Of Alaska, Thomas C. Weber, Chris Rooper, John L. Butler, Darin Jones, Chris Wilson Jan 2013

Seabed Classification For Trawlability Determined With A Multibeam Echo Sounder On Snakehead Bank In The Gulf Of Alaska, Thomas C. Weber, Chris Rooper, John L. Butler, Darin Jones, Chris Wilson

Center for Coastal and Ocean Mapping

—Rockfishes (Sebastes spp.) tend to aggregate near rocky, cobble, or generally rugged areas that are difficult to survey with bottom trawls, and evidence indicates that assemblages of rockfish species may differ between areas accessible to trawling and those areas that are not. Consequently, it is important to determine grounds that are trawlable or untrawlable so that the areas where trawl survey results should be applied are accurately identified. To this end, we used multibeam echosounder data to generate metrics that describe the seafloor: backscatter strength at normal and oblique incidence angles, the variation of the angle-dependent backscatter strength within 10° …

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A Procedure For Developing An Acceptance Test For Airborne Bathymetric Lidar Data Application To Noaa Charts In Shallow Waters, Gretchen Imahori, Jeffrey Ferguson, Toshi Wozumi, Dave Scharff, Shachak Pe'eri, Christopher Parrish, Stephen A. White, Inseong Jeong, Jon Sellars, Michael Aslaksen Jan 2013

A Procedure For Developing An Acceptance Test For Airborne Bathymetric Lidar Data Application To Noaa Charts In Shallow Waters, Gretchen Imahori, Jeffrey Ferguson, Toshi Wozumi, Dave Scharff, Shachak Pe'eri, Christopher Parrish, Stephen A. White, Inseong Jeong, Jon Sellars, Michael Aslaksen

Center for Coastal and Ocean Mapping

National Oceanic and Atmospheric Administration (NOAA) hydrographic data is typically acquired using sonar systems, with a small percent acquired via airborne lidar bathymetry for near‐shore areas. This study investigated an integrated approach for meeting NOAA’s hydrographic survey requirements for near‐shore areas of NOAA charts, using the existing topographic‐bathymetric lidar data from USACE’s National Coastal Mapping Program (NCMP). Because these existing NCMP bathymetric lidar datasets were not collected to NOAA hydrographic surveying standards, it is unclear if, and under what circumstances, they might aid in meeting certain hydrographic surveying requirements. The NCMP’s bathymetric lidar data are evaluated through a comparison to …

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Ricamar2013: Rilievi Per La Caratterizzazione Dell'ambiente Marino Nel Golfo Di Pozzuoli. Rapporto Sull'attivita 13 - 31 Maggio 2013, C. Carmisciano, M. Grassi, L. Cocchi, Giuseppe Masetti, M. Filippone, E. Ricci, M. Pratellesi, Roberta Ivaldi, Giovanni Iannaccone, Giovanna Berrino, Guiseppe De Natale, Giovanni Chiodini, Sefano Caliro, Lorenzo Dialti, Matteo Guideri, F. Muccini, Paolo Stefanelli, Giovanni Orsi, Valerio Iafolla, Francesco Italiano, Fabrizia Buongiorno, Salvatore Stramondo, Christian Bignami, Marco Polcari, Malvina Silvestri Jan 2013

Ricamar2013: Rilievi Per La Caratterizzazione Dell'ambiente Marino Nel Golfo Di Pozzuoli. Rapporto Sull'attivita 13 - 31 Maggio 2013, C. Carmisciano, M. Grassi, L. Cocchi, Giuseppe Masetti, M. Filippone, E. Ricci, M. Pratellesi, Roberta Ivaldi, Giovanni Iannaccone, Giovanna Berrino, Guiseppe De Natale, Giovanni Chiodini, Sefano Caliro, Lorenzo Dialti, Matteo Guideri, F. Muccini, Paolo Stefanelli, Giovanni Orsi, Valerio Iafolla, Francesco Italiano, Fabrizia Buongiorno, Salvatore Stramondo, Christian Bignami, Marco Polcari, Malvina Silvestri

Center for Coastal and Ocean Mapping

No abstract provided.

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Spatial Structure And Dynamics Of The Plant Communities In A Pro-Grading River Delta : Wax Lake Delta, Atchafalaya Bay, Louisiana, Melissa Carle Jan 2013

Spatial Structure And Dynamics Of The Plant Communities In A Pro-Grading River Delta : Wax Lake Delta, Atchafalaya Bay, Louisiana, Melissa Carle

LSU Doctoral Dissertations

River deltas are dynamic depositional environments that are controlled to varying degrees by coastal and fluvial forces. Plant communities in deltas respond to many of the same allogenic forces that shape delta geomorphology. This study examines the factors that influence plant community development, productivity, and species distributions in the Wax Lake delta, a young, actively pro-grading river delta in coastal Louisiana, USA. A species distribution map created using high-resolution 8-band WorldView-2 imagery was found to have an overall accuracy of 75 percent. Classification tree analysis suggested that most of the observed variation in plant species distributions within the delta can …

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A Multi-Scale Investigation Of Nutrient Dynamics In The Lake Pontchartrain Estuary And Basin, Eric Daniel Roy Jan 2013

A Multi-Scale Investigation Of Nutrient Dynamics In The Lake Pontchartrain Estuary And Basin, Eric Daniel Roy

LSU Doctoral Dissertations

Humans are responsible for global-scale alteration of nitrogen (N) and phosphorus (P) biogeochemical cycles to support food production. Increases in N and P inputs into soils and waste-streams has resulted in excessive nutrient loading to surface waters, including the Mississippi River, leading to eutrophication. Here I investigated N and P dynamics occurring in the Lake Pontchartrain Estuary and Basin. I measured two biogeochemical processes using intact sediment core incubations and quantified their importance in the context of nutrient-rich Mississippi River flood diversions through the Bonnet Carré Spillway. I show that diffusion of nitrate-N into sediments accounts for a substantial magnitude …

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Decade-Scale Nutrient Enrichment Effects On Wetland Plant Community Structure, Function, And Stability, Sean A. Graham Jan 2013

Decade-Scale Nutrient Enrichment Effects On Wetland Plant Community Structure, Function, And Stability, Sean A. Graham

LSU Doctoral Dissertations

Human activities have increased the supply of nitrogen (N) and phosphorus (P) to coastal waters worldwide, threatening coastal wetlands with excess nutrient loading and subsequent eutrophication. In this dissertation, I present results from two decade-scale fertilization experiments in a Sagittaria lancifolia dominated oligohaline marsh that examined the species-, community-, and ecosystem-level effects of nutrient enrichment. My objectives were to determine (1) which nutrient limits primary production, (2) how increased supply of the limiting nutrient affects plant community structure and function, both above- and belowground, and (3) whether nutrient over-enrichment compromises ecosystem stability. Overall, significant changes in plant growth occurred with …

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