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Articles 1951 - 1980 of 4562

Full-Text Articles in Oceanography and Atmospheric Sciences and Meteorology

Effects Of Temperature, Irradiance And Pco2 On The Growth And Nitrogen Utilization Of Prorocentrum Donghaiense, Zhangxi Hu, Margaret R. Mulholland, Ning Xu, Shunshan Duan Jan 2016

Effects Of Temperature, Irradiance And Pco2 On The Growth And Nitrogen Utilization Of Prorocentrum Donghaiense, Zhangxi Hu, Margaret R. Mulholland, Ning Xu, Shunshan Duan

OES Faculty Publications

Environmental factors such as temp erature, irradiance, and nitrogen (N) supply affect the growth of Prorocentrum donghaiense, but the interactive effects of these physical factors and the effects of atmospheric CO2 (pCO2) on growth and N uptake have not been examined. We compared growth kinetics of P. donghaiense grown on 4 different N substrates (nitrate [NO3 -], ammonium [NH4 +], urea, and glutamic acid [glu]) with respect to temperature, irradiance, and pCO2. Temperature (15 to 30°C) had a positive effect on growth (max. growth rates: 0.17 to 0.65 d …


Sea Level Acceleration In The China Seas, Yongcun Cheng, Tal Ezer, Benjamin D. Hamlington Jan 2016

Sea Level Acceleration In The China Seas, Yongcun Cheng, Tal Ezer, Benjamin D. Hamlington

CCPO Publications

While global mean sea level rise (SLR) and acceleration (SLA) are indicators of climate change and are informative regarding the current state of the climate, assessments of regional and local SLR are essential for policy makers responding to, and preparing for, changes in sea level. In this work, three acceleration detection techniques are used to demonstrate the robust SLA in the China Seas. Interannual to multidecadal sea level variations (periods >2 years), which are mainly related to natural internal climate variability and significantly affect estimation of sea level acceleration, are removed with empirical mode decomposition (EMD) analysis prior to the …


Gross And Microscopic Lesions In Corals From Micronesia, T. M. Work, G. S. Aeby, K. A. Hughen Jan 2016

Gross And Microscopic Lesions In Corals From Micronesia, T. M. Work, G. S. Aeby, K. A. Hughen

United States Geological Survey: Staff Publications

The authors documented gross and microscopic morphology of lesions in corals on 7 islands spanning western, southern, and eastern Micronesia, sampling 76 colonies comprising 30 species of corals among 18 genera, with Acropora, Porites, and Montipora dominating. Tissue loss comprised the majority of gross lesions sampled (41%), followed by discoloration (30%) and growth anomaly (29%). Of 31 cases of tissue loss, most lesions were subacute (48%), followed by acute and chronic (26% each). Of 23 samples with discoloration, most were dark discoloration (40%), with bleaching and other discoloration each constituting 30%. Of 22 growth anomalies, umbonate growth anomalies composed …


Bioaccessibility Tests Accurately Estimate Bioavailability Of Lead To Quail, W. Nelson Beyer, Nicholas T. Basta, Rufus L. Chaney, Paula F.P. Henry, David E. Mosby, Barnett A. Rattner, Kirk G. Scheckel, Daniel T. Sprague, John S. Weber Jan 2016

Bioaccessibility Tests Accurately Estimate Bioavailability Of Lead To Quail, W. Nelson Beyer, Nicholas T. Basta, Rufus L. Chaney, Paula F.P. Henry, David E. Mosby, Barnett A. Rattner, Kirk G. Scheckel, Daniel T. Sprague, John S. Weber

United States Geological Survey: Staff Publications

Hazards of soil-borne lead (Pb) to wild birds may be more accurately quantified if the bioavailability of that Pb is known. To better understand the bioavailability of Pb to birds, the authors measured blood Pb concentrations in Japanese quail (Coturnix japonica) fed diets containing Pb-contaminated soils. Relative bioavailabilities were expressed by comparison with blood Pb concentrations in quail fed a Pb acetate reference diet. Diets containing soil from 5 Pb-contaminated Superfund sites had relative bioavailabilities from 33% to 63%, with a mean of approximately 50%. Treatment of 2 of the soils with phosphorus (P) significantly reduced the bioavailability …


A Personal Perspective On Searching For The Ivory-Billed Woodpecker: A 41-Year Quest, Paul W. Sykes Jr. Jan 2016

A Personal Perspective On Searching For The Ivory-Billed Woodpecker: A 41-Year Quest, Paul W. Sykes Jr.

United States Geological Survey: Staff Publications

I first learned about the Patuxent Wildlife Research Center (Patuxent) in Laurel, MD, while attending high school in the mid-1950s. Patuxent wildlife biologists Brooke Meanley, Chandler (Chan) S. Robbins, and Robert (Bob) E. Stewart, Sr., visited me at my parents’ home in Norfolk, VA. I was the compiler of the Norfolk County Christmas Bird Count (which included the eastern portion of the Virginia sector of the Dismal Swamp). As part of that count, we had for several years been estimating populations of red-winged blackbirds (Agelaius phoeniceus) and common grackles (Quiscalus quiscula) in the millions. Patuxent was …


Patuxent’S Role In The Development Of The North American Breeding Bird Survey, John R. Sauer Jan 2016

Patuxent’S Role In The Development Of The North American Breeding Bird Survey, John R. Sauer

United States Geological Survey: Staff Publications

The North American Breeding Bird Survey (BBS) is a roadside survey of the breeding birds of North America. The BBS provides data from the contiguous United States, Alaska, southern and central Canada, and northern Mexico. Begun in 1966 by Chandler (Chan) S. Robbins at the U.S. Geological Survey (USGS) Patuxent Wildlife Research Center (Patuxent), and now jointly managed by Patuxent, the Canadian Wildlife Service, and the Mexican Commission for the Knowledge and Use of Biodiversity, the survey is conducted primarily in June along more than 5,000 roadside survey routes that are surveyed once each year. Volunteer observers drive the 39.4-kilometer …


Patuxent’S Long-Term Research On Wolves, David L. Mech Jan 2016

Patuxent’S Long-Term Research On Wolves, David L. Mech

United States Geological Survey: Staff Publications

The gray wolf (Canis lupus) was one of the first species placed on the Endangered Species List in 1967. The Endangered Species Act of 1973 legally protected the wolf along with other listed species. Patuxent Wildlife Research Center (Patuxent) in Laurel, MD, began its Endangered Wildlife Program in 1966, and U.S. Fish and Wildlife Service (USFWS) biologist Ray Erickson was assigned to lead it. In 1973, I was transferred to the program from Region 3 of the USFWS, having been employed there since 1969 to study wolves in Minnesota. Endangered Species Act protection of the wolf fostered its …


A Spatio-Temporal Comparison Of Avian Migration Phenology Using Citizen Science Data, Ali Arab, Jason R. Courter, Jessica Zelt Jan 2016

A Spatio-Temporal Comparison Of Avian Migration Phenology Using Citizen Science Data, Ali Arab, Jason R. Courter, Jessica Zelt

United States Geological Survey: Staff Publications

The effects of climate change have wide-ranging impacts on wildlife species and recent studies indicate that birds’ spring arrival dates are advancing in response to changes in global climates. In this paper, we propose a spatio-temporal approach for comparing avian first arrival data for multiple species. As an example, we analyze spring arrival data for two long-distance migrants (Rubythroated Hummingbird Archilochus colubris; and Purple Martin Progne subis) in eastern North America from 2001–2010 using Citizen Science data. The proposed approach provides researchers with a tool to compare mean arrival dates while accounting for spatial and temporal variability. Our results show …


Phosphorus Retention In A Lowland Neotropical Stream Following An Eight-Year Enrichment Experiment, Gaston E. Small, Marcelo Ardón, John H. Duff, Alan P. Jackman, Alonso Ramírez, Frank J. Triska, Catherine M. Pringle Jan 2016

Phosphorus Retention In A Lowland Neotropical Stream Following An Eight-Year Enrichment Experiment, Gaston E. Small, Marcelo Ardón, John H. Duff, Alan P. Jackman, Alonso Ramírez, Frank J. Triska, Catherine M. Pringle

United States Geological Survey: Staff Publications

Human alteration of the global P cycle has led to widespread P loading in freshwater ecosystems. Much research has been devoted to the capacity of wetlands and lakes to serve as long-term sinks for P inputs from the watershed, but we know much less about the potential of headwater streams to serve in this role. We assessed storage and retention of P in biotic and abiotic compartments after an 8-y experimental P addition to a 1st-order stream in a Neotropical wet forest. Sediment P extractions indicated that nearly all P storage was in the form of Fe- and Al-bound P …


Droughtscape, Winter 2016, Kelly Smith Jan 2016

Droughtscape, Winter 2016, Kelly Smith

DroughtScape: Quarterly Newsletter of the National Drought Mitigation Center (2007–2023)

Contents

Director’s column

California drought FAQ

October-December 2015 drought

October-December 2015 impacts

2015 drought impacts in review

NDMC hiring geospatial analyst

CA drought exposes social vulnerability

UA helps Arizona ranchers, Forest Service work together

NDMC and partners help southern Plains ranchers manage drought

Chickasaw ranching workshop


A Step In The Right Direction: Streambank Restoration Efforts At The Botanical Garden Of The Ozarks, Dylan S. Milholen, Madison Brown, Steven Thao, Lisa S. Wood Jan 2016

A Step In The Right Direction: Streambank Restoration Efforts At The Botanical Garden Of The Ozarks, Dylan S. Milholen, Madison Brown, Steven Thao, Lisa S. Wood

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

The Botanical Garden of the Ozarks (BGO) is a unique destination in Northwest Arkansas that draws more than 80,000 visitors a year. While the BGO manages low-input practices, run-off from pesticide application and synthetic fertilizers containing phosphorus and nitrogen are of concern to water quality, habitat, and overall ecological interactions of the BGO streambanks and adjacent Hilton Creek, which flows directly into Lake Fayetteville. One way to reduce pollution to waterbodies is through the use of riparian buffers. This project sought to establish a riparian buffer immediately adjacent to a portion of Hilton Creek in an effort to improve ecological …


Changing Winds And Rising Tides On Beach Renourishment In Florida: Short-Term Alternatives And Long-Term Sustainable Solutions Using Law And Policy From Florida And Nearby States, Lewis Van Alstyne Iii Jan 2016

Changing Winds And Rising Tides On Beach Renourishment In Florida: Short-Term Alternatives And Long-Term Sustainable Solutions Using Law And Policy From Florida And Nearby States, Lewis Van Alstyne Iii

Florida A & M University Law Review

Sandy beaches make up 825 miles of Florida's 1,260 total miles of coastline around the Sunshine State's peninsula. These beaches are changing over time due to the natural erosional forces of wind and water. Coastal engineering attempts to halt natural forces with man-made structures such as buildings, piers, groins, jetties, breakwaters, sea walls, ports, inlets, and in some cases, it creates new sandy beaches and world-class cities where none existed. In an effort to protect the new real estate from the erosion that has always existed, engineers created beach nourishment. This Article focuses on building up beaches through beach nourishment. …


River Report. State Of The Lower St. Johns River Basin, Florida: Water Quality, Fisheries, Aquatic Life, Contaminants, 2016, Environmental Protection Board, City Of Jacksonville, University Of North Florida, Jacksonville University, Gerry Pinto, Nisse Goldberg, Radha Pyati, Peter Bacopoulos, Anthony Ouellette, Gretchen Bielmyer-Fraser, An-Phong Le, Ray Oldakowski Jan 2016

River Report. State Of The Lower St. Johns River Basin, Florida: Water Quality, Fisheries, Aquatic Life, Contaminants, 2016, Environmental Protection Board, City Of Jacksonville, University Of North Florida, Jacksonville University, Gerry Pinto, Nisse Goldberg, Radha Pyati, Peter Bacopoulos, Anthony Ouellette, Gretchen Bielmyer-Fraser, An-Phong Le, Ray Oldakowski

State of the River Report

No abstract provided.


Upper Tropospheric Water Vapour Variability At High Latitudes- Part 1: Influence Of The Annular Modes, Christopher E. Sioris, Jason Zou, David A. Plummer, Chris D. Boone, C. Thomas Mcelroy, Patrick E. Sheese, Omid Moeini, Peter F. Bernath Jan 2016

Upper Tropospheric Water Vapour Variability At High Latitudes- Part 1: Influence Of The Annular Modes, Christopher E. Sioris, Jason Zou, David A. Plummer, Chris D. Boone, C. Thomas Mcelroy, Patrick E. Sheese, Omid Moeini, Peter F. Bernath

Chemistry & Biochemistry Faculty Publications

Seasonal and monthly zonal medians of water vapour in the upper troposphere and lower stratosphere (UTLS) are calculated for both Atmospheric Chemistry Experiment (ACE) instruments for the northern and southern high-latitude regions (60-90° N and 60-90°S). Chosen for the purpose of observing high-latitude processes, the ACE orbit provides sampling of both regions in 8 of 12 months of the year, with coverage in all seasons. The ACE water vapour sensors, namely MAESTRO (Measurements of Aerosol Extinction in the Stratosphere and Troposphere Retrieved by Occultation) and the Fourier Transform Spectrometer (ACE-FTS) are currently the only satellite instruments that can probe from …


Geospatial Approaches To Support Pelagic Conservation Planning And Adaptive Management, L. M. Wedding, Sara M. Maxwell, D. Hyrenbach, D. C. Dunn, J. J. Roberts, D. Briscoe, E. Hines, P. N. Halpin Jan 2016

Geospatial Approaches To Support Pelagic Conservation Planning And Adaptive Management, L. M. Wedding, Sara M. Maxwell, D. Hyrenbach, D. C. Dunn, J. J. Roberts, D. Briscoe, E. Hines, P. N. Halpin

Biological Sciences Faculty Publications

Place-based management in the open ocean faces unique challenges in delineating boundaries around temporally and spatially dynamic systems that span broad geographic scales and multiple management jurisdictions, especially in the 'high seas'. Geospatial technologies are critical for the successful design of pelagic conservation areas, because they provide information on the spatially and temporally dynamic oceanographic features responsible for driving species distribution and abundance in the open ocean, the movements of protected species, and the spatial patterns of distribution of potential threats. Nevertheless, there are major challenges to implementing these geospatial approaches in the open ocean. This Theme Section seeks to …


Assessing The Evolution Of Soil Moisture And Vegetation Conditions During The 2012 United States Flash Drought, Jason A. Otkin, Martha C. Anderson, Christopher R. Hain, Mark D. Svoboda, David K. Johnson, Richard Mueller, Tsegaye Tadesse, Brian D. Wardlow, Jesslyn Brown Jan 2016

Assessing The Evolution Of Soil Moisture And Vegetation Conditions During The 2012 United States Flash Drought, Jason A. Otkin, Martha C. Anderson, Christopher R. Hain, Mark D. Svoboda, David K. Johnson, Richard Mueller, Tsegaye Tadesse, Brian D. Wardlow, Jesslyn Brown

National Drought Mitigation Center: Faculty Publications

This study examines the evolution of several model-based and satellite-derived drought metrics sensitive to soil moisture and vegetation conditions during the extreme flash drought event that impacted major agricultural areas across the central U.S. during 2012. Standardized anomalies from the remote sensing based Evaporative Stress Index (ESI) and Vegetation Drought Response Index (VegDRI) and soil moisture anomalies from the North American Land Data Assimilation System (NLDAS) are compared to the United States Drought Monitor (USDM), surface meteorological conditions, and crop and soil moisture data compiled by the National Agricultural Statistics Service (NASS).

Overall, the results show that rapid decreases in …


The Implications Of Climate Change For Nebraska: Summary Report Of Sector-Based Roundtable Discussions, Donald A. Wilhite, Kimberly Morrow Jan 2016

The Implications Of Climate Change For Nebraska: Summary Report Of Sector-Based Roundtable Discussions, Donald A. Wilhite, Kimberly Morrow

National Drought Mitigation Center: Faculty Publications

This report is the result of the work of many individuals that contributed to the success of the series of eight sector-based roundtable events that were held in September and October of 2015. First and foremost, we would like to thank the organizers and the organizations they represent for their leadership in bringing together a diverse set of key stakeholders to discuss the implications of climate change on their sector. It was such a pleasure to work with such a dedicated group of individuals. Second, we would like to thank the more than 350 people who participated in these discussions …


New Tools For Assessing Drought Conditions For Rangeland Management, Cody Knutson, Brian Fuchs Jan 2016

New Tools For Assessing Drought Conditions For Rangeland Management, Cody Knutson, Brian Fuchs

National Drought Mitigation Center: Faculty Publications

Historical drought assessment and ongoingmonitoring is essential for understanding past drought occurrence, the relationships between past drought and its impacts, and for triggering action during current drought events. • A variety of new products have recently been developed to better monitor drought conditions and assess past occurrences at the local scale. • A growing number of resources are available to assist rangeland managers to develop a monitoring system and incorporate it into a drought management plan.


Predicting The Water Quality Of Shallow Arctic Ponds Using Remote Sensing, Gabriela Tarin Jan 2016

Predicting The Water Quality Of Shallow Arctic Ponds Using Remote Sensing, Gabriela Tarin

Open Access Theses & Dissertations

Barrow, Alaska is in a region dominated by Arctic tundra of which a substantial part is covered by lakes and ponds. Despite their dominance in the landscape, freshwater ecosystems in the Arctic have been insufficiently studied. It is clear that furthering understanding of how Arctic water bodies are responding to warming will depend on the analysis of changes in the concentration of organic and inorganic constituents in the water; however, scientists are faced with the task of sampling many remote sites in a relatively hostile environment. Thus, the exploration and incorporation of remote methods for monitoring changes in water quality. …


Study Of No2 Photolysis Rate Coefficients For The Paso Del Norte Region, Pema Wangchuk Jan 2016

Study Of No2 Photolysis Rate Coefficients For The Paso Del Norte Region, Pema Wangchuk

Open Access Theses & Dissertations

The photolysis of nitrogen dioxide is one of the most influential chemical processes in the formation of photochemical air pollution. In this study, we compared simulated and measured nitrogen dioxide photolysis rate coefficients (J_(NO_2 )) for the Paso Del Norte (PdN) region. The Tropospheric Ultraviolet-Visible (TUV) radiation transfer model was used to calculate J_(NO_2 ) values. The measurements of hemi-spherically integrated, spectrally resolved solar photon flux between the wavelengths 400 and 700 nm were used to obtain the photolysis rate coefficients for ã??NOã??_2. Results are presented for a selected episode on July, 2015. The work investigated the use of measured …


Relocation Based On Slow-Onset Climate-Induced Environmental Change In Keta, Ghana, Abdul-Moomin Ansong Salifu Jan 2016

Relocation Based On Slow-Onset Climate-Induced Environmental Change In Keta, Ghana, Abdul-Moomin Ansong Salifu

Walden Dissertations and Doctoral Studies

Coastal indigenous communities in Keta, Ghana, are experiencing resettlement as a result of slow-onset, climate-induced flooding and erosion. Previous researchers have documented the risk of relocation from rapid-onset events, but little is known about the effectiveness of policies developed in response to slow-onset changes. This phenomenological study investigated the ongoing lived experiences of adult household members in Keta who were relocated by the government. Jun's critical theory provided a constructionist interpretive framework to determine whether Ghana's national policy on climate change resettlement adequately meets Rawls's criteria for distributive social justice. Policy documents and transcriptions of interviews with a purposeful sample …


Statistical Analysis Of The Effectiveness Of Seawalls And Coastal Forests In Mitigating Tsunami Impacts In Iwate And Miyagi Prefectures, Roshanak Nateghi, Jeremy D. Bricker, Seth D. Guikema, Akane Bessho Jan 2016

Statistical Analysis Of The Effectiveness Of Seawalls And Coastal Forests In Mitigating Tsunami Impacts In Iwate And Miyagi Prefectures, Roshanak Nateghi, Jeremy D. Bricker, Seth D. Guikema, Akane Bessho

School of Industrial Engineering Faculty Publications

The Pacific coast of the Tohoku region of Japan experiences repeated tsunamis, with the most recent events having occurred in 1896, 1933, 1960, and 2011. These events have caused large loss of life and damage throughout the coastal region. There is uncertainty about the degree to which seawalls reduce deaths and building damage during tsunamis in Japan. On the one hand they provide physical protection against tsunamis as long as they are not overtopped and do not fail. On the other hand, the presence of a seawall may induce a false sense of security, encouraging additional development behind the seawall …


Building Resiliency In Response To Sea Level Rise And Recurrent Flooding: Comprehensive Planning In Hampton Roads, Joshua G. Behr, Rafael Diaz, Molly Mitchell Jan 2016

Building Resiliency In Response To Sea Level Rise And Recurrent Flooding: Comprehensive Planning In Hampton Roads, Joshua G. Behr, Rafael Diaz, Molly Mitchell

VMASC Publications

[Introduction]

Over the past few decades, the Hampton Roads region, with its extensive coastline, has been experiencing more frequent flooding from surges and precipitation caused by tropical storms, nor’easters and heavy thunderstorms (Figure 1). Recurrent flooding is “flooding that occurs repeatedly in the same area over time due to precipitation events, high tides or storm surge.”1 The recurrence of tidal/surge flooding in Hampton Roads has increased from 1.7 days of “nuisance” flooding per year in 1960 to 7.3 days per year in 2014.2 Although there is no definitive region-wide data to document the increases in precipitation-induced flooding, there …


Coherent Late-Holocene Climate-Driven Shifts In The Structure Of Three Rocky Mountain Lakes, Jeffrey R. Stone, Jasmine E. Saros, Gregory T. Pederson Jan 2016

Coherent Late-Holocene Climate-Driven Shifts In The Structure Of Three Rocky Mountain Lakes, Jeffrey R. Stone, Jasmine E. Saros, Gregory T. Pederson

United States Geological Survey: Staff Publications

Large-scale atmospheric pressure centers, such as the Aleutian and Icelandic Low, have a demonstrated relationship with physical lake characteristics in contemporary monitoring studies, but the responses to these phenomena are rarely observed in lake records. We observe coherent changes in the stratification patterns of three deep (>30 m) lakes inferred from fossil diatom assemblages as a response to shifts in the location and intensity of the Aleutian Low and compare these changes with similar long-term changes observed in the 18O record from the Yukon. Specifically, these records indicate that between 3.2 and 1.4 ka, the Aleutian Low shifted …


Using Satellite Vegetation And Compound Topographic Indices To Maphighly Erodible Cropland Buffers For Cellulosic Biofuel Cropdevelopments In Eastern Nebraska, Usa, Yingxin Gu, Bruce K. Wylie Jan 2016

Using Satellite Vegetation And Compound Topographic Indices To Maphighly Erodible Cropland Buffers For Cellulosic Biofuel Cropdevelopments In Eastern Nebraska, Usa, Yingxin Gu, Bruce K. Wylie

United States Geological Survey: Staff Publications

Cultivating annual row crops in high topographic relief waterway buffers has negative environmental effects and can be environmentally unsustainable. Growing perennial grasses such as switchgrass(Panicum virgatum L.) for biomass (e.g., cellulosic biofuel feedstocks) instead of annual row crops in these high relief waterway buffers can improve local environmental conditions (e.g., reduce soil erosion and improve water quality through lower use of fertilizers and pesticides) and ecosystem services (e.g.,minimize drought and flood impacts on production; improve wildlife habitat, plant vigor, and nitro-gen retention due to post-senescence harvest for cellulosic biofuels; and serve as carbon sinks). The main objectives of this …


Deep Subsurface Drip Irrigation Using Coal-Bed Sodic Water: Part Ii. Geochemistry, Carleton R. Bern, George N. Breit, Richard W. Healy, John W. Zupancic Jan 2016

Deep Subsurface Drip Irrigation Using Coal-Bed Sodic Water: Part Ii. Geochemistry, Carleton R. Bern, George N. Breit, Richard W. Healy, John W. Zupancic

United States Geological Survey: Staff Publications

Waters with low salinity and high sodium adsorption ratios (SARs) present a challenge to irrigation because they degrade soil structure and infiltration capacity. In the Powder River Basin of Wyoming, such low salinity (electrical conductivity, EC 2.1 mS cm−1) and high-SAR (54) waters are co-produced with coal-bed methane and some are used for subsurface drip irrigation (SDI). The SDI system studied mixes sulfuric acid with irrigation water and applies water year-round via drip tubing buried 92 cm deep. After six years of irrigation, SAR values between 0 and 30 cm depth (0.5–1.2) are only slightly increased over non-irrigated …


Geochemical Evidence For Seasonal Controls On The Transportation Of Holocene Loess, Matanuska Valley, Southern Alaska, Usa, Daniel R. Muhs, James R. Budahn, Gary Skipp, John P. Mcgeehin Jan 2016

Geochemical Evidence For Seasonal Controls On The Transportation Of Holocene Loess, Matanuska Valley, Southern Alaska, Usa, Daniel R. Muhs, James R. Budahn, Gary Skipp, John P. Mcgeehin

United States Geological Survey: Staff Publications

Loess is a widespread Quaternary deposit in Alaska and loess accretion occurs today in some regions, such as the Matanuska Valley. The source of loess in the Matanuska Valley has been debated for more than seven decades, with the Knik River and the Matanuska River, both to the east, being the leading candidates and the Susitna River, to the west, as a less favorable source. We report here new stratigraphic, mineralogic, and geochemical data that test the competing hypotheses of these river sources. Loess thickness data are consistent with previous studies that show that a source or sources lay to …


Retrospective: Adjusting Contaminant Concentrations In Bird Eggs To Account For Moisture And Lipid Loss During Their Incubation, Barnett A. Rattner, Stanley N. Wiemeyer, Lawrence J. Blus Jan 2016

Retrospective: Adjusting Contaminant Concentrations In Bird Eggs To Account For Moisture And Lipid Loss During Their Incubation, Barnett A. Rattner, Stanley N. Wiemeyer, Lawrence J. Blus

United States Geological Survey: Staff Publications

By the 1960s, research and monitoring efforts on chlorinated

pesticide residues in tissues of wildlife were well

underway in North America and Europe. Conservationists

and natural resource managers were attempting to resolve

whether pesticide exposure and accumulated residues were

related to population declines in several species of predatory

and scavenging birds (e.g., bald eagle Haliaeetus

leucocephalus, peregrine falcon Falco peregrinus, brown

pelican Pelecanus occidentalis and osprey Pandion haliaetus).

The avian egg was a favored sampling matrix even

before the realization that eggshell thinning was linked to

population declines (Ratcliffe 1967; Hickey and Anderson

1968) and that the …


Component Greenhouse Gas Fluxes And Radiative Balance From Two Deltaic Marshes In Louisiana: Pairing Chamber Techniques And Eddy Covariance, Ken W. Krauss, Guerry O. Holm Jr., Brian C. Perez, David E. Mcwhorter, Nicole Cormier, Rebecca F. Moss, Darren J. Johnson, Scott C. Neubauer, Richard C. Raynie Jan 2016

Component Greenhouse Gas Fluxes And Radiative Balance From Two Deltaic Marshes In Louisiana: Pairing Chamber Techniques And Eddy Covariance, Ken W. Krauss, Guerry O. Holm Jr., Brian C. Perez, David E. Mcwhorter, Nicole Cormier, Rebecca F. Moss, Darren J. Johnson, Scott C. Neubauer, Richard C. Raynie

United States Geological Survey: Staff Publications

Coastal marshes take up atmospheric CO2 while emitting CO2, CH4, and N2O. This ability to sequester carbon (C) is much greater for wetlands on a per area basis than from most ecosystems, facilitating scientific, political, and economic interest in their value as greenhouse gas sinks. However, the greenhouse gas balance of Gulf of Mexico wetlands is particularly understudied. We describe the net ecosystem exchange (NEEc) of CO2 and CH4 using eddy covariance (EC) in comparison with fluxes of CO2, CH4, and N2O using …


Mapping Marginal Croplands Suitable For Cellulosic Feedstock Crops In The Great Plains, United States, Yingxin Gu, Bruce K. Wylie Jan 2016

Mapping Marginal Croplands Suitable For Cellulosic Feedstock Crops In The Great Plains, United States, Yingxin Gu, Bruce K. Wylie

United States Geological Survey: Staff Publications

Growing cellulosic feedstock crops (e.g., switchgrass) for biofuel is more environmentally sustainable than cornbased ethanol. Specifically, this practice can reduce soil erosion and water quality impairment from pesticides and fertilizer, improve ecosystem services and sustainability (e.g., serve as carbon sinks), and minimize impacts on global food supplies. The main goal of this study was to identify high-risk marginal croplands that are potentially suitable for growing cellulosic feedstock crops (e.g., switchgrass) in the US Great Plains (GP). Satellitederived growing season Normalized Difference Vegetation Index, a switchgrass biomass productivity map obtained from a previous study, US Geological Survey (USGS) irrigation and crop …