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What Climate Change Means For Nebraska May 2024

What Climate Change Means For Nebraska

United States Environmental Protection Agency: Staff Publications

Nebraska’s climate is changing. In the past century, most of the state has warmed by at least one degree (F). The soil is becoming drier, and rainstorms are becoming more intense. In the coming decades, flooding is likely to increase, yet summers are likely to become increasingly hot and dry, which would reduce yields of some crops, require farmers to use more water, and amplify some risks to human health.

Our climate is changing because the earth is warming. People have increased the amount of carbon dioxide in the air by 40 percent since the late 1700s. Other heat-trapping greenhouse …


The Natural History And Ecology Of Melanism In Red Wolf And Coyote Populations Of The Southeastern United States – Evidence For Gloger’S Rule, Joseph W. Hinton, Kyla M. West, Daniel J. Sullivan, Jacqueline L. Frair, Michael J. Chamberlain Jun 2022

The Natural History And Ecology Of Melanism In Red Wolf And Coyote Populations Of The Southeastern United States – Evidence For Gloger’S Rule, Joseph W. Hinton, Kyla M. West, Daniel J. Sullivan, Jacqueline L. Frair, Michael J. Chamberlain

United States Environmental Protection Agency: Staff Publications

Background: Gloger’s rule postulates that animals should be darker colored in warm and humid regions where dense vegetation and dark environments are common. Although rare in Canis populations, melanism in wolves is more common in North America than other regions globally and is believed to follow Gloger’s rule. In the temperate forests of the southeastern United States, historical records of red wolf (Canis rufus) and coyote (Canis latrans) populations document a consistent presence of melanism. Today, the melanistic phenotype is extinct in red wolves while occurring in coyotes and red wolf-coyote hybrids who occupy the …


Integrating Lidar Data And Multi-Temporal Aerial Imagery To Map Wetland Inundation Dynamics Using Google Earth Engine, Qiusheng Wu, Charles B. Lane, Xuecao Li, Kaiguang Zhao, Yuyu Zhou, Nicholas Clinton, Ben Devries, Heather E. Golden, Megan W. Lang Dec 2019

Integrating Lidar Data And Multi-Temporal Aerial Imagery To Map Wetland Inundation Dynamics Using Google Earth Engine, Qiusheng Wu, Charles B. Lane, Xuecao Li, Kaiguang Zhao, Yuyu Zhou, Nicholas Clinton, Ben Devries, Heather E. Golden, Megan W. Lang

United States Environmental Protection Agency: Staff Publications

The Prairie Pothole Region of North America is characterized by millions of depressional wetlands, which provide critical habitats for globally significant populations of migratory waterfowl and other wildlife species. Due to their relatively small size and shallow depth, these wetlands are highly sensitive to climate variability and anthropogenic changes, exhibiting inter- and intra-annual inundation dynamics. Moderate-resolution satellite imagery (e.g., Landsat, Sentinel) alone cannot be used to effectively delineate these small depressional wetlands. By integrating fine spatial resolution Light Detection and Ranging (LiDAR) data and multi-temporal (2009–2017) aerial images, we developed a fully automated approach to delineate wetland inundation extent at …


The Effects Of Combinations Of Limited Ration And Diazinon Exposure On Acetylcholinesterase Activity, Growth And Reproduction In Oryzias Latipes, The Japanese Medaka, Kevin Flynn, Rodney Johnson, Doug Lothenbach, Joe Swintek, Frank Whiteman, Matthew Etterson Oct 2019

The Effects Of Combinations Of Limited Ration And Diazinon Exposure On Acetylcholinesterase Activity, Growth And Reproduction In Oryzias Latipes, The Japanese Medaka, Kevin Flynn, Rodney Johnson, Doug Lothenbach, Joe Swintek, Frank Whiteman, Matthew Etterson

United States Environmental Protection Agency: Staff Publications

Environmental contamination can negatively impact fish populations. In addition to acute toxicity leading to death, toxicants can reduce fish growth and lower reproduction. The potential for adverse population level effects of environmental contaminants are estimated to conduct risk assessments from laboratory toxicity tests that most often measure apical endpoints related to growth, survival and reproduction. The relationships between these effect endpoints are being evaluated to predict shifts in fish population demography better after exposure to environmental toxicants. Environmental contaminants can also affect fish populations indirectly by reducing prey biomass. However, estimating the magnitude of the combined effects of prey reduction …


Seasonality Of Nitrogen Balances In A Mediterranean Climate Watershed, Oregon, Us, Jiajia Lin, Jana E. Compton, Scott G. Leibowitz, George Mueller-Warrant, William Matthews, Stephen H. Schoenholtz, Daniel M. Evans, Rob A. Coulombe Dec 2018

Seasonality Of Nitrogen Balances In A Mediterranean Climate Watershed, Oregon, Us, Jiajia Lin, Jana E. Compton, Scott G. Leibowitz, George Mueller-Warrant, William Matthews, Stephen H. Schoenholtz, Daniel M. Evans, Rob A. Coulombe

United States Environmental Protection Agency: Staff Publications

We constructed a seasonal nitrogen (N) budget for the year 2008 in the Calapooia River Watershed (CRW), an agriculturally dominated tributary of the Willamette River (Oregon, U.S.) under Mediterranean climate. Synthetic fertilizer application to agricultural land (dominated by grass seed crops) was the source of 90% of total N input to the CRW. Over 70% of the stream N export occurred during the wet winter, the primary time of fertilization and precipitation, and the lowest export occurred in the dry summer. Averaging across all 58 tributary subwatersheds, 19% of annual N inputs were exported by streams, and 41% by crop …


Preface: Workshop On Pesticide Exposure Assessment Paradigm For Non-Apis Bees, Richard Bireley, Shannon Borges, Karina Cham, David Epstein, Kristina Garber, Connie Hart, Wayne Hou, Alessio Ippolito, Jens Pistorius, Veronique Poulsen, Keith Sappington, Thomas Steeger Dec 2018

Preface: Workshop On Pesticide Exposure Assessment Paradigm For Non-Apis Bees, Richard Bireley, Shannon Borges, Karina Cham, David Epstein, Kristina Garber, Connie Hart, Wayne Hou, Alessio Ippolito, Jens Pistorius, Veronique Poulsen, Keith Sappington, Thomas Steeger

United States Environmental Protection Agency: Staff Publications

Since the mid-2000s, increased annual losses of honey bee (Apis mellifera L., Hymenoptera: Apidae) colonies and declines in some species of non-Apis bees have been reported (Biesmeijer et al. 2006, NRC 2007). These losses, particularly with respect to honey bees, have been associated with multiple factors including pesticides, pathogens (viruses, fungi, bacteria), pests (primarily the parasitic mite Varroa destructor Anderson and Trueman [Arachnida: Parasitiformes: Varroidae]), poor nutrition, and bee management practices acting in combination (vanEngelsdorp et al. 2008, 2009; Ratnieks et al. 2010). Because of the role that bees play in providing pollination services to natural and agricultural-based ecosystems, …


The Effects Of Continuous Diazinon Exposure On Growth And Reproduction In Japanese Medaka Using A Modified Medaka Extended One Generation Reproduction Test (Meogrt), Kevin Flynn, Doug Lothenbach, Frank Whiteman, Dean Hammermeister, Joe Swintek, Matthew Etterson, Rodney Johnson Jul 2018

The Effects Of Continuous Diazinon Exposure On Growth And Reproduction In Japanese Medaka Using A Modified Medaka Extended One Generation Reproduction Test (Meogrt), Kevin Flynn, Doug Lothenbach, Frank Whiteman, Dean Hammermeister, Joe Swintek, Matthew Etterson, Rodney Johnson

United States Environmental Protection Agency: Staff Publications

The Medaka Extended One Generation Reproduction Test (MEOGRT) is a Tier 2 test within U.S. Environmental Protection Agency's (USEPA) Endocrine Disruptor Screening Program (EDSP), designed to characterize the potential adverse effects to fish of exposure to chemical that can cause disruption of the endocrine system. The MEOGRT focuses primarily on adverse effects to reproduction while collecting information regarding effects on growth, survival, and endocrine-related endpoints. However, the risk assessment process for fish, as mandated by legislation such as the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) or the Toxic Substances Control Act (TSCA), could benefit from a more detailed assessment …


Coupling Toxicokinetic–Toxicodynamic And Population Models For Assessing Aquatic Ecological Risks To Time-Varying Pesticide Exposures, Glen Thursby, Keith Sappington, Matthew Etterson Jul 2018

Coupling Toxicokinetic–Toxicodynamic And Population Models For Assessing Aquatic Ecological Risks To Time-Varying Pesticide Exposures, Glen Thursby, Keith Sappington, Matthew Etterson

United States Environmental Protection Agency: Staff Publications

Population modeling evaluations of pesticide exposure time series were compared with aspects of a currently used risk assessment process. The US Environmental Protection Agency’s Office of Pesticide Programs models daily aquatic 30-yr pesticide exposure distributions in its risk assessments, but does not routinely make full use of the information in such time series.We used mysid shrimp Americamysis bahia toxicity and demographic data to demonstrate the value of a toxicokinetic– toxicodynamic model coupled with a series of matrix population models in risk assessment refinements. This species is a small epibenthic marine crustacean routinely used in regulatory toxicity tests. We demonstrate how …


Sensitivity Analyses For Simulating Pesticide Impacts On Honey Bee Colonies, A. Carmen Kuan, Gloria Degrandi-Hoffman, Robert J. Curry, Kristina V. Garber, Andrew R. Kanarek, Marcia N. Snyder, Kurt L. Wolfe, S. Thomas Purucker Mar 2018

Sensitivity Analyses For Simulating Pesticide Impacts On Honey Bee Colonies, A. Carmen Kuan, Gloria Degrandi-Hoffman, Robert J. Curry, Kristina V. Garber, Andrew R. Kanarek, Marcia N. Snyder, Kurt L. Wolfe, S. Thomas Purucker

United States Environmental Protection Agency: Staff Publications

We employ Monte Carlo simulation and sensitivity analysis techniques to describe the population dynamics of pesticide exposure to a honey bee colony using the VarroaPop+Pesticide model. Simulations are performed of hive population trajectories with and without pesticide exposure to determine the effects of weather, queen strength, foraging activity, colony resources, and Varroa populations on colony growth and survival. The daily resolution of the model allows us to conditionally identify sensitivity metrics. Simulations indicate queen strength and forager lifespan are consistent, critical inputs for colony dynamics in both the control and exposed conditions. Adult contact toxicity, application rate and nectar load …


Reproductive Success And Contaminant Associations In Tree Swallows (Tachycineta Bicolor) Used To Assess A Beneficial Use Impairment In U.S. And Binational Great Lakes’ Areas Of Concern, Christine M. Custer, Thomas W. Custer, Matthew A. Etterson, Paul M. Dummer, Diana Goldberg, J. Christian Franson Mar 2018

Reproductive Success And Contaminant Associations In Tree Swallows (Tachycineta Bicolor) Used To Assess A Beneficial Use Impairment In U.S. And Binational Great Lakes’ Areas Of Concern, Christine M. Custer, Thomas W. Custer, Matthew A. Etterson, Paul M. Dummer, Diana Goldberg, J. Christian Franson

United States Environmental Protection Agency: Staff Publications

During 2010-2014, tree swallow (Tachycineta bicolor) reproductive success was monitored at 68 sites across all 5 Great Lakes, including 58 sites located within Great Lakes Areas of Concern (AOCs) and 10 non-AOCs. Sample eggs were collected from tree swallow clutches and analyzed for contaminants including polychlorinated biphenyls (PCBs), dioxins and furans, polybrominated diphenyl ethers, and 34 other organic compounds. Contaminant data were available for 360 of the clutches monitored. Markov chain multistate modeling was used to assess the importance of 5 ecological variables and 11 of the dominant contaminants in explaining the pattern of egg and nestling failure …


Estimates Of Present And Future Flood Risk In The Conterminous United States, Oliver E.J. Wing, Paul D. Bates, Andrew M. Smith, Christopher C. Sampson, Kris A. Johnson, Joseph Fargione, Philip Morefield Feb 2018

Estimates Of Present And Future Flood Risk In The Conterminous United States, Oliver E.J. Wing, Paul D. Bates, Andrew M. Smith, Christopher C. Sampson, Kris A. Johnson, Joseph Fargione, Philip Morefield

United States Environmental Protection Agency: Staff Publications

Past attempts to estimate rainfall-driven flood risk across the US either have incomplete coverage, coarse resolution or use overly simplified models of the flooding process. In this paper, we use a new 30m resolution model of the entire conterminous US with a 2D representation of flood physics to produce estimates of flood hazard, which match to within 90% accuracy the skill of local models built with detailed data. These flood depths are combined with exposure datasets of commensurate resolution to calculate current and future flood risk. Our data show that the total US population exposed to serious flooding is 2.6–3.1 …


A Framework For Linking Population Model Development With Ecological Risk Assessment Objectives, Sandy Raimondo, Matthew Etterson, Nathan Pollesch, Kristina Garber, Andrew Kanarek, Wade Lehmann, Jill Awkerman Dec 2017

A Framework For Linking Population Model Development With Ecological Risk Assessment Objectives, Sandy Raimondo, Matthew Etterson, Nathan Pollesch, Kristina Garber, Andrew Kanarek, Wade Lehmann, Jill Awkerman

United States Environmental Protection Agency: Staff Publications

The value of models that link organism-level impacts to the responses of a population in ecological risk assessments (ERAs) has been demonstrated extensively over the past few decades. There is little debate about the utility of these models to translate multiple organism-level endpoints into a holistic interpretation of effect to the population; however, there continues to be a struggle for actual application of these models as a common practice in ERA. Although general frameworks for developing models for ERA have been proposed, there is limited guidance on when models should be used, in what form, and how to interpret model …


Factors Associated With Bat Mortality At Wind Energy Facilities In The United States, Maureen Thompson, Julie A. Beston, Matthew Etterson, Jay E. Diffendorfer, Scott R. Loss Sep 2017

Factors Associated With Bat Mortality At Wind Energy Facilities In The United States, Maureen Thompson, Julie A. Beston, Matthew Etterson, Jay E. Diffendorfer, Scott R. Loss

United States Environmental Protection Agency: Staff Publications

Hundreds of thousands of bats are killed annually by colliding with wind turbines in the U.S., yet little is known about factors causing variation in mortality across wind energy facilities. We conducted a quantitative synthesis of bat collision mortality with wind turbines by reviewing 218 North American studies representing 100 wind energy facilities. This data set, the largest compiled for bats to date, provides further evidence that collision mortality is greatest for migratory tree-roosting species (Hoary Bat [Lasiurus cinereus], Eastern Red Bat [Lasiurus borealis], Silver-haired Bat [Lasionycteris noctivagans]) and from July to October. Based …


Model Application Niche Analysis: Assessing The Transferability And Generalizability Of Ecological Models, Jessica B. Moon, Theodore H. Dewitt, Melissa N. Errend, Randall J. F. Bruins, Mary E. Kentula, Sarah J. Chamberlain, M. Siobhan Fennessy, Kusum J. Naithani Aug 2017

Model Application Niche Analysis: Assessing The Transferability And Generalizability Of Ecological Models, Jessica B. Moon, Theodore H. Dewitt, Melissa N. Errend, Randall J. F. Bruins, Mary E. Kentula, Sarah J. Chamberlain, M. Siobhan Fennessy, Kusum J. Naithani

United States Environmental Protection Agency: Staff Publications

The use of models by ecologists and environmental managers, to inform environmental management and decision-making, has grown exponentially in the past 50 yr. Due to logistical, economical, and theoretical benefits, model users frequently transfer preexisting models to new sites where data are scarce. Modelers have made significant progress in understanding how to improve model generalizability during model development. However, models are always imperfect representations of systems and are constrained by the contextual frameworks used during their development. Thus, model users need better ways to evaluate the possibility of unintentional misapplication when transferring models to new sites. We propose a method …


Mechanistic Modeling Of Insecticide Risks To Breeding Birds In North American Agroecosystems, Matthew Etterson, Kristina Garber, Edward Odenkirchen May 2017

Mechanistic Modeling Of Insecticide Risks To Breeding Birds In North American Agroecosystems, Matthew Etterson, Kristina Garber, Edward Odenkirchen

United States Environmental Protection Agency: Staff Publications

Insecticide usage in the United States is ubiquitous in urban, suburban, and rural environments. There is accumulating evidence that insecticides adversely affect non-target wildlife species, including birds, causing mortality, reproductive impairment, and indirect effects through loss of prey base, and the type and magnitude of such effects differs by chemical class, or mode of action. In evaluating data for an insecticide registration application and for registration review, scientists at the United States Environmental Protection Agency (USEPA) assess the fate of the insecticide and the risk the insecticide poses to the environment and non-target wildlife. Current USEPA risk assessments for pesticides …


Factors That Influence Vital Rates Of Seaside And Saltmarsh Sparrows In Coastal New Jersey, Usa, Samuel G. Roberts, Rebecca A. Longenecker, Matthew A. Etterson, Katharine J. Ruskin, Chris S. Elphick, Brian J. Olsen, W. Gregory Shriver Mar 2017

Factors That Influence Vital Rates Of Seaside And Saltmarsh Sparrows In Coastal New Jersey, Usa, Samuel G. Roberts, Rebecca A. Longenecker, Matthew A. Etterson, Katharine J. Ruskin, Chris S. Elphick, Brian J. Olsen, W. Gregory Shriver

United States Environmental Protection Agency: Staff Publications

As saltmarsh habitat continues to disappear, understanding the factors that influence the population dynamics of saltmarsh breeding birds is an important step in the conservation of these declining species. Using 5 yrs (2011–2015) of demographic data, we evaluated and compared apparent adult survival and nest survival of Seaside (Ammodramus maritimus) and Saltmarsh (A. caudacutus) sparrows at the Edwin B. Forsythe National Wildlife Refuge in New Jersey, USA. We determined the effect of site management history (unditched vs. ditched marshes) on adult and nest survival to aid in prioritizing future management or restoration actions. Apparent adult …


Statistical Survey Of Persistent Organic Pollutants: Risk Estimations To Humans And Wildlife Through Consumption Of Fish From U.S. Rivers, Angela L. Batt, John B. Wathen, James M. Lazorchak, Anthony R. Olsen, Thomas M. Kincaid Jan 2017

Statistical Survey Of Persistent Organic Pollutants: Risk Estimations To Humans And Wildlife Through Consumption Of Fish From U.S. Rivers, Angela L. Batt, John B. Wathen, James M. Lazorchak, Anthony R. Olsen, Thomas M. Kincaid

United States Environmental Protection Agency: Staff Publications

U.S. EPA conducted a national statistical survey of fish tissue contamination at 540 river sites (representing 82 954 river km) in 2008−2009, and analyzed samples for 50 persistent organic pollutants (POPs), including 21 PCB congeners, 8 PBDE congeners, and 21 organochlorine pesticides. The survey results were used to provide national estimates of contamination for these POPs. PCBs were the most abundant, being measured in 93.5% of samples. Summed concentrations of the 21 PCB congeners had a national weighted mean of 32.7 μg/kg and a maximum concentration of 857 μg/kg, and exceeded the human health cancer screening value of 12 μg/kg …


A Photosynthesis-Based Two-Leaf Canopy Stomatal Conductance Model For Meteorology And Air Quality Modeling With Wrf/Cmaq Px Lsm, Limei Ran, Jonathan Pleim, Conghe Song, Larry Band, John T. Walker, Francis S. Binkowski Jan 2017

A Photosynthesis-Based Two-Leaf Canopy Stomatal Conductance Model For Meteorology And Air Quality Modeling With Wrf/Cmaq Px Lsm, Limei Ran, Jonathan Pleim, Conghe Song, Larry Band, John T. Walker, Francis S. Binkowski

United States Environmental Protection Agency: Staff Publications

A coupled photosynthesis-stomatal conductance model with single-layer sunlit and shaded leaf canopy scaling is implemented and evaluated in a diagnostic box model with the Pleim-Xiu land surface model (PX LSM) and ozone deposition model components taken directly from the meteorology and air quality modeling system—WRF/CMAQ (Weather Research and Forecast model and Community Multiscale Air Quality model). The photosynthesis-based model for PX LSM (PX PSN) is evaluated at a FLUXNET site for implementation against different parameterizations and the current PX LSM approach with a simple Jarvis function (PX Jarvis). Latent heat flux (LH) from PX PSN is further evaluated at five …


Atp Binding Cassette Sub-Family Member 2 (Abcg2) And Xenobiotic Exposure During Early Mouse Embryonic Stem Cell Differentiation, Mitchell B. Rosen, Susan C. Jeffay, Harriette P. Nichols, Maria R. Hoopes, E. Sidney Hunter Iii Jan 2017

Atp Binding Cassette Sub-Family Member 2 (Abcg2) And Xenobiotic Exposure During Early Mouse Embryonic Stem Cell Differentiation, Mitchell B. Rosen, Susan C. Jeffay, Harriette P. Nichols, Maria R. Hoopes, E. Sidney Hunter Iii

United States Environmental Protection Agency: Staff Publications

Background: ATP binding cassette sub-family member 2 (ABCG2) is a welldefined efflux transporter found in a variety of tissues. The role of ABCG2 during early embryonic development, however, is not established. Previous work which compared data from the ToxCast screening program with that from in-house studies suggested an association exists between exposure to xenobiotics that regulate Abcg2 transcription and differentiation of mouse embryonic stem cells (mESC), a relationship potentially related to redox homeostasis.

Methods: mESC were grown for up to 9 days. Pharmacological inhibitors were used to assess transporter function with and without xenobiotic exposure. Proliferation and differentiation were …


Weight Of Evidence Evaluation Of A Network Of Adverse Outcome Pathways Linking Activation Of The Nicotinic Acetylcholine Receptor In Honey Bees To Colony Death, Carlie A. Lalone, Daniel L. Villeneuve, Judy Wu-Smart, Rebecca Y. Milsk, Keith Sappington, Kristina V. Garber, Justin Housenger, Gerald T. Ankley Jan 2017

Weight Of Evidence Evaluation Of A Network Of Adverse Outcome Pathways Linking Activation Of The Nicotinic Acetylcholine Receptor In Honey Bees To Colony Death, Carlie A. Lalone, Daniel L. Villeneuve, Judy Wu-Smart, Rebecca Y. Milsk, Keith Sappington, Kristina V. Garber, Justin Housenger, Gerald T. Ankley

United States Environmental Protection Agency: Staff Publications

Ongoing honey bee (Apis mellifera) colony losses are of significant international concern because of the essential role these insects play in pollinating crops. Both chemical and non-chemical stressors have been implicated as possible contributors to colony failure; however, the potential role(s) of commonly-used neonicotinoid insecticides has emerged as particularly concerning. Neonicotinoids act on the nicotinic acetylcholine receptors (nAChRs) in the central nervous system to eliminate pest insects. However, mounting evidence indicates that neonicotinoids also may adversely affect beneficial pollinators, such as the honey bee, via impairments on learning and memory, and ultimately foraging success. The specificmechanisms linking activation …


Seasonal Fecundity Is Not Related To Geographic Position Across A Species’ Global Range Despite A Central Peak In Abundance, Katharine J. Ruskin, Matthew A. Etterson, Thomas P. Hodgman, Alyssa C. Borowske, Jonathan B. Cohen, Chris S. Elphick, Christopher R. Field, Rebecca A. Kern, Erin King, Alison R. Kocek, Adrienne I. Kovach, Kathleen M. O’Brien, Nancy Pau, W. Gregory Shriver, Jennifer Walsh, Brian J. Olsen Oct 2016

Seasonal Fecundity Is Not Related To Geographic Position Across A Species’ Global Range Despite A Central Peak In Abundance, Katharine J. Ruskin, Matthew A. Etterson, Thomas P. Hodgman, Alyssa C. Borowske, Jonathan B. Cohen, Chris S. Elphick, Christopher R. Field, Rebecca A. Kern, Erin King, Alison R. Kocek, Adrienne I. Kovach, Kathleen M. O’Brien, Nancy Pau, W. Gregory Shriver, Jennifer Walsh, Brian J. Olsen

United States Environmental Protection Agency: Staff Publications

The range of a species is determined by the balance of its demographic rates across space. Population growth rates are widely hypothesized to be greatest at the geographic center of the species range, but indirect empirical support for this pattern using abundance as a proxy has been mixed, and demographic rates are rarely quantified on a large spatial scale. Therefore, the texture of how demographic rates of a species vary over its range remains an open question. We quantified seasonal fecundity of populations spanning the majority of the global range of a single species, the saltmarsh sparrow (Ammodramus caudacutus …


Using Ecological Production Functions To Link Ecological Processes To Ecosystem Services, Randall Jf Bruins, Timothy J. Canfield, Clifford Duke, Larry Kapustka, Amanda M. Nahlik, Ralf B. Schäfer Aug 2016

Using Ecological Production Functions To Link Ecological Processes To Ecosystem Services, Randall Jf Bruins, Timothy J. Canfield, Clifford Duke, Larry Kapustka, Amanda M. Nahlik, Ralf B. Schäfer

United States Environmental Protection Agency: Staff Publications

Ecological production functions (EPFs) link ecosystems, stressors, and management actions to ecosystem services (ES) production. Although EPFs are acknowledged as being essential to improve environmental management, their use in ecological risk assessment has received relatively little attention. Ecological production functions may be defined as usable expressions (i.e., models) of the processes by which ecosystems produce ES, often including external influences on those processes. We identify key attributes of EPFs and discuss both actual and idealized examples of their use to inform decision making. Whenever possible, EPFs should estimate final, rather than intermediate, ES. Although various types of EPFs have been …


Influence Of Resource Availability On Juniperus Virginiana Expansion In A Forest–Prairie Ecotone, A. C. Ganguli, D. M. Engle, P. M. Mayer, L. F. Salo Aug 2016

Influence Of Resource Availability On Juniperus Virginiana Expansion In A Forest–Prairie Ecotone, A. C. Ganguli, D. M. Engle, P. M. Mayer, L. F. Salo

United States Environmental Protection Agency: Staff Publications

Woody plant expansion into grasslands and savannas is a global concern. Rapid expansion of Juniperus virginiana, a tree native to North America, has profound ecological consequences. We used transplanted J. virginiana seedlings to investigate the role of resource availability on J. virginiana expansion following the removal of fire, the factor historically limiting range expansion of this fire-intolerant species. We evaluated J. virginiana seedling survival and seedling growth, two important phases in woody plant expansion, relative to two below ground resource factors, plant-available soil water (soil clay content, an index of plant-available soil water) and plant-available nitrogen (PAN), and an above …


A Comparison Between 2010 And 2006 Air Quality And Meteorological Conditions, And Emissions And Boundary Conditions Used In Simulations Of The Aqmeii-2 North American Domain, Till E. Stoeckenius, Christian Hogrefe, Justin Zagunis, Timonthy M. Sturtz, Benjamin Wells, Tanarit Sakulyanontvittaya Jan 2016

A Comparison Between 2010 And 2006 Air Quality And Meteorological Conditions, And Emissions And Boundary Conditions Used In Simulations Of The Aqmeii-2 North American Domain, Till E. Stoeckenius, Christian Hogrefe, Justin Zagunis, Timonthy M. Sturtz, Benjamin Wells, Tanarit Sakulyanontvittaya

United States Environmental Protection Agency: Staff Publications

Several participants in Phase 2 of the Air Quality Model Evaluation International Initiative (AQMEII-2) who are applying coupled models to the North American domain are comparing model results for two years, 2006 and 2010, with the goal of performing dynamic model evaluation. From a modeling perspective, the differences of interest are the large reductions in domain total emissions of NOx (21%) and SO2 (37%) from 2006 to 2010 and significant differences in meteorological conditions between these two years. The emission reductions occurred mostly in the eastern U.S, with some reduction in emissions from western wildfires in 2010. Differences …


Seasonality Of Coliform Bacteria Detection Rates In New Jersey Domestic Wells, Thomas B. Atherholt, Nicholas A. Procopio, Sandra M. Goodrow Jan 2016

Seasonality Of Coliform Bacteria Detection Rates In New Jersey Domestic Wells, Thomas B. Atherholt, Nicholas A. Procopio, Sandra M. Goodrow

United States Environmental Protection Agency: Staff Publications

It is important that indicators of fecal pollution are reliable. Coliform bacteria are a commonly used indicator of fecal pollution. As other investigators have reported elsewhere, we observed a seasonal pattern of coliform bacteria detections in domestic wells in New Jersey. Examination of a statewide database of 10 years of water quality data from 93,447 samples, from 78,207 wells, generated during real estate transactions, revealed that coliform bacteria were detected in a higher proportion of wells during warm weather months. Further examination of the seasonal pattern of other data, including well water pH, precipitation, ground and surface water temperatures, surface …


Alpha-Lipoic Acid Supplementation Protects Enzymes From Damage By Nitrosative And Oxidative Stress, Sylvia Hiller, Robert Dekroon, Eric D. Hamlett, Longquan Xu, Cristina Osorio, Jennifer Robinette, Witold Winnik, Stephen Simington, Nobuyo Maeda, Oscar Alzate, Xianwen Yi Jan 2016

Alpha-Lipoic Acid Supplementation Protects Enzymes From Damage By Nitrosative And Oxidative Stress, Sylvia Hiller, Robert Dekroon, Eric D. Hamlett, Longquan Xu, Cristina Osorio, Jennifer Robinette, Witold Winnik, Stephen Simington, Nobuyo Maeda, Oscar Alzate, Xianwen Yi

United States Environmental Protection Agency: Staff Publications

Background: S-nitrosylation of mitochondrial enzymes involved in energy transfer under nitrosative stress may result in ATP deficiency. We investigated whether α-lipoic acid, a powerful antioxidant, could alleviate nitrosative stress by regulating S-nitrosylation,which could result in retaining themitochondrial enzyme activity.

Methods: In this study, we have identified the S-nitrosylated forms of subunit 1 of dihydrolipoyllysine succinyltransferase (complex III), and subunit 2 of the α-ketoglutarate dehydrogenase complex by implementing a fluorescence-based differential quantitative proteomics method.

Results: We found that the activities of these two mitochondrial enzymes were partially but reversibly inhibited by S-nitrosylation in cultured endothelial cells, and that their activities …


Estimating Ozone And Secondary Pm2.5 Impacts From Hypothetical Single Source Emissions In The Central And Eastern United States, Kirk R. Baker, Robert A. Kotchenruther, Rynda C. Hudman Jan 2016

Estimating Ozone And Secondary Pm2.5 Impacts From Hypothetical Single Source Emissions In The Central And Eastern United States, Kirk R. Baker, Robert A. Kotchenruther, Rynda C. Hudman

United States Environmental Protection Agency: Staff Publications

Secondary pollutant impacts from emissions of single sources may need to be assessed to satisfy a variety of regulatory requirements including the Clean Air Act New Source Review and Prevention of Significant Deterioration programs and the National Environmental Policy Act. In this work, single source impacts on O3 and secondary PM2.5 are estimated with annual 2011 photochemical grid model simulations where new hypothetical sources are added to the central and eastern United States with varying precursor emission rates and emission release heights. Impacts from these hypothetical sources are tracked with photochemical grid model source apportionment. Single source impacts …


Temporal Trends In The Spatial Distribution Of Impervious Cover Relative To Stream Location, J. Wickham, A. Neale, M. Mehaffey, T. Jarnagin, D. Norton Jan 2016

Temporal Trends In The Spatial Distribution Of Impervious Cover Relative To Stream Location, J. Wickham, A. Neale, M. Mehaffey, T. Jarnagin, D. Norton

United States Environmental Protection Agency: Staff Publications

Use of impervious cover is transitioning from an indicator of surface water condition to one that also guides and informs watershed planning and management, including Clean Water Act (33 U.S.C. §1251 et seq.) reporting. Whether it is for understanding surface water condition or planning and management, impervious cover is most commonly expressed as summary measurement (e.g., percentage watershed in impervious cover). We use the National Land Cover Database to estimate impervious cover in the vicinity of surface waters for three time periods (2001, 2006, 2011). We also compare impervious cover in the vicinity of surface waters to watershed summary estimates …


Carbon Storage In Us Wetlands, A. M. Nahlik, M. S. Fennessy Jan 2016

Carbon Storage In Us Wetlands, A. M. Nahlik, M. S. Fennessy

United States Environmental Protection Agency: Staff Publications

Wetland soils contain some of the highest stores of soil carbon in the biosphere. However, there is little understanding of the quantity and distribution of carbon stored in our remaining wetlands or of the potential effects of human disturbance on these stocks. Here we use field data from the 2011 National Wetland Condition Assessment to provide unbiased estimates of soil carbon stocks for wetlands at regional and national scales. We find that wetlands in the conterminous United States store a total of 11.52 PgC, much of which is within soils deeper than 30 cm. Freshwater inland wetlands, in part due …


Water Consumption Estimates Of The Biodiesel Process In The Us, Qingshi Tu, Mingming Lu, Y. Jeffrey Yang, Don Scott Jan 2016

Water Consumption Estimates Of The Biodiesel Process In The Us, Qingshi Tu, Mingming Lu, Y. Jeffrey Yang, Don Scott

United States Environmental Protection Agency: Staff Publications

As a renewable alternative to petroleum diesel, biodiesel has been widely used in the US and the world. However, its potential impact on water resources has not been much evaluated. This study investigates water consumption from the biodiesel process, which includes three stages: soybean irrigation, soybean-to-soybean oil processing, and biodiesel manufacturing, at both national and state levels. Mass-based allocation is performed and water consumption at the three stages is obtained on the basis of million gallons per year and gallon water per gallon biodiesel (gal/gal). The normalized water consumption (water intensity) of the irrigation, oil processing, and biodiesel production stages …