Other Environmental Sciences Commons^™

Estimation Of Crop Gross Primary Production (Gpp): FaparChl Versus Mod15a2 Fpar, Qingyuan Zhang, Yen-Ben Cheng, A. I. Lyapustin, Yujie Wang, Feng Gao, Andrew E. Suyker, Shashi B. Verma, Elizabeth M. Middleton

School of Natural Resources: Faculty Publications

Photosynthesis (PSN) is a pigment level process in which antenna pigments (predominately chlorophylls) in chloroplasts absorb photosynthetically active radiation (PAR) for the photochemical process. PAR absorbed by foliar non-photosynthetic components is not used for PSN. The fraction of PAR absorbed (fAPAR) by a canopy/vegetation (i.e., fAPAR_canopy) derived from the Moderate Resolution Imaging Spectroradiometer (MODIS) images, referred to as MOD15A2 FPAR, has been used to compute absorbed PAR (APAR) for PSN (APAR_PSN) which is utilized to produce the standard MODIS gross primary production (GPP) product, referred to as MOD17A2 GPP. In this study, the fraction of PAR …

You Are Not Always What We Think You Eat: Selective Assimilation Across Multiple Whole-Stream Isotopic Tracer Studies, W. K. Dodds, S. M. Collins, S. K. Hamilton, J. L. Tank, S. Johnson, J. R. Webster, K. S. Simon, M. R. Whiles, H. M. Rantala, W. H. Mcdowell, S. D. Peterson, T. Riis, C. L. Crenshaw, S. A. Thomas, P. B. Kristensen, B. M. Cheever, A. S. Flecker, N. A. Griffiths, T. Crowl, E. J. Rosi-Marshall, R. El-Sabaawi, E. Marti

School of Natural Resources: Faculty Publications

Analyses of 21 ¹⁵N stable isotope tracer experiments, designed to examine food web dynamics in streams around the world, indicated that the isotopic composition of food resources assimilated by primary consumers (mostly invertebrates) poorly reflected the presumed food sources. Modeling indicated that consumers assimilated only 33–50% of the N available in sampled food sources such as decomposing leaves, epilithon, and fine particulate detritus over feeding periods of weeks or more. Thus, common methods of sampling food sources consumed by animals in streams do not sufficiently reflect the pool of N they assimilate. Isotope tracer studies, combined with modeling and …

Estimation Of Crop Gross Primary Production (Gpp): I. Impact Of Modisobservation Footprint And Impact Of Vegetation Brdf Characteristics, Qingyuan Zhang, Yen-Ben Cheng, Alexei I. Lyapustin, Yujie Wang, Xiangming Xiao, Andrew E. Suyker, Shashi Verma, Bin Tan, Elizabeth M. Middleton

School of Natural Resources: Faculty Publications

Accurate estimation of gross primary production (GPP) is essential for carbon cycle and climate change studies. Three AmeriFlux crop sites of maize and soybean were selected for this study. Two of the sites were irrigated and the other one was rainfed. The normalized difference vegetation index (NDVI), the enhanced vegetation index (EVI), the green band chlorophyll index (CI_green), and the green band wide dynamic range vegetation index (WDRVI_green) were computed from the moderate resolution imaging spectroradiometer (MODIS) surface reflectance data. We examined the impacts of the MODIS observation footprint and the vegetation bidirectional reflectance distribution function …

2014 Interior Least Tern And Piping Plover Monitoring, Research, Management, And Outreach Report For The Lower Platte River, Nebraska, Mary Bomberger Brown, Joel G. Jorgensen, Lauren R. Dinan

School of Natural Resources: Faculty Publications

This document reports on our monitoring, research, management, and outreach activities during the past 12 months (2013–2014). We prepared it to inform our partners, cooperating agencies, funding sources, and other interested parties of our activities and to provide a preliminary summary of our results.

The lower Platte River and its major tributaries provide important nesting and migratory stopover habitat for two bird species of special conservation concern: the state and federally endangered Interior Least Tern (Sternula antillarum athalassos) and threatened Piping Plover (Charadrius melodus). The Tern and Plover Conservation Partnership (TPCP), based at the University of …

Spatial Accuracy Of Climate Networks: A Case Study In Nebraska, Andrea J. Coop, Kenneth Hubbard, Martha Shulski, Jinsheng You, David B. Marx

School of Natural Resources: Faculty Publications

Climate data are increasingly scrutinized for accuracy because of the need for reliable input for climaterelated decision making and assessments of climate change. Over the last 30 years, vast improvements to U.S. instrumentation, data collection, and station siting have created more accurate data. This study explores the spatial accuracy of daily maximum and minimum air temperature data in Nebraska networks, including the U.S. Historical Climatology Network (HCN), the Automated Weather Data Network (AWDN), and the more recent U.S. Climate Reference Network (CRN). The spatial structure of temperature variations at the earth’s surface is compared for timeframes 2005–09 for CRN and …

Iron Clad Wetlands: Soil Iron-Sulfur Buffering Determines Coastal Wetland Response To Salt Water Incursion, Valerie Anne Schoepfer, Emily S. Bernhardt, Amy J. Burgin

School of Natural Resources: Faculty Publications

Coastal freshwater wetland chemistry is rapidly changing due to increased frequency of salt water incursion, a consequence of global change. Seasonal salt water incursion introduces sulfate, which microbially reduces to sulfide. Sulfide binds with reduced iron, producing iron sulfide (FeS), recognizable in wetland soils by its characteristic black color. The objective of this study is to document iron and sulfate reduction rates, as well as product formation (acid volatile sulfide (AVS) and chromium reducible sulfide (CRS)) in a coastal freshwater wetland undergoing seasonal salt water incursion. Understanding iron and sulfur cycling, as well as their reduction products, allows us to …

Coupled Heat And Vapor Transport: The Thermostat Effect Of A Freely Evaporating Land Surface, Jozsef Szilagyi, Aaron Schepers

School of Natural Resources: Faculty Publications

Analytical solutions of the 2-D heat and vapor transport equations for a surface moisture jump are often based on a constant streamwise temperature (T_ws) assumption over the wet vegetated surface. By analyzing 90 thermal infrared images taken over center-pivot irrigated areas in Nebraska, it has been demonstrated for the first time that such an assumption is realistic. Average temperature difference between the perimeter and core of the irrigated full or half circles stayed between -0.11 and 0.09°C (standard deviation of 0.25–0.41°C). It was further demonstrated that wet-bulb temperatures (a proxy of T_ws) remain near constant during …

Analysis And Mapping Of Climate Change Risk And Vulnerability In Central Rift Valley Of Ethiopia, L. Gizachew, A. Shiferaw

School of Natural Resources: Faculty Publications

No abstract provided.

Piping Plovers Charadrius Melodus And Dogs: Compliance With And Attitudes Toward A Leash Law On Public Beaches At Lake Mcconaughy, Nebraska, Usa, Joel G. Jorgensen, Mary Bomberger Brown

School of Natural Resources: Faculty Publications

Humans often recreate with their dogs Canis familiaris on public beaches; beaches that may also be used as breeding habitat by imperiled shorebirds. The Piping Plover Charadrius melodus is one such shorebird and is protected by the Endangered Species Act 1973 (ESA) in the United States. Dogs, especially dogs that are not restrained and allowed access to breeding areas because their owners choose not abide by “leash laws,” will sometimes negatively impact Piping Plovers. We evaluated leash-law compliance and recreationists’ awareness of and attitudes toward leash laws at Lake McConaughy, Nebraska, USA, during 2013–2014. Leash-law compliance was chronically low (< 25% of all dogs observed) during all days and time periods we evaluated, even though 78.1% of recreationists with dogs were aware of the leash-law requirements. All 487 individuals surveyed possessed favorable attitudes towards Piping Plovers and continued dog access to the beach, while having generally unfavorable attitudes toward unleashed dogs. It appears the potential exists at Lake McConaughy to improve leash-law compliance through a comprehensive program that uses education, enforcement and reinforcement of social norms.

How Mangrove Forests Adjust To Rising Sea Level, Ken W. Krauss, Karen L. Mckee, Catherine E. Lovelock, Donald R. Cahoon, Neil Saintilan, Ruth Reef, Luzhen Chen

United States Geological Survey: Staff Publications

Mangroves are among the most well described and widely studied wetland communities in the world. The greatest threats to mangrove persistence are deforestation and other anthropogenic disturbances that can compromise habitat stability and resilience to sea-level rise. To persist, mangrove ecosystems must adjust to rising sea level by building vertically or become submerged. Mangroves may directly or indirectly influence soil accretion processes through the production and accumulation of organic matter, as well as the trapping and retention of mineral sediment. In this review, we provide a general overview of research on mangrove elevation dynamics, emphasizing the role of the vegetation …

Conservation Of Energy: An Analytical Tool For Student Accounts Of Carbon-Transforming Processes, J. Dauer, H. Miller, C. W. Anderson

School of Natural Resources: Faculty Publications

No abstract provided.

Measured And Modeled Soil Moisture Compared With Cosmic-Ray Neutron Probe Estimates In A Mixed Forest, L. Ling, T. Franz, D. Robinson, S. Jones

School of Natural Resources: Faculty Publications

No abstract provided.

Eastern Wild Turkey Reproductive Ecology In Longleaf Pine Forests, Andrew R. Little, Mary M. Streich, Michael J. Chamberlain, L. Mike Conner, Robert J. Warren, Joseph W. Jones

School of Natural Resources: Faculty Publications

No abstract provided.

Esterification Pretreatment Of Free Fatty Acid In Biodiesel Production, From Laboratory To Industry, Ming Chai, Qingshi Tu, Jeffrey Y. Yang, Mingming Lu

United States Environmental Protection Agency: Publications

In the United States, biodiesel producers usually follow the 19.8:1 methanol-to-FFA molar ratio for free fatty acid (FFA) esterification, as suggested by the National Renewable Energy Laboratory (NREL) without optimization studies. In this paper, both laboratory studies and industrial practices of the esterification process were compared, and an optimization study of a used vegetable oil with 5% FFA was conducted. The optimal conditions of this oil, i.e., methanol-to-FFA molar ratio of 40:1, and sulfuric acid usage of 10%, fell out of the suggested range of 19.8:1. The activation energy of the esterification reaction is 20.7 kJ/mol at the optimized condition …

Bringing Resilience To Wildlife Management And Biodiversity Protection, Melinda Harm Benson, Matthew E. Hopton

United States Environmental Protection Agency: Publications

Biological diversity can be considered both temporally (Le., evolutionary time) and/or spatially and reflects the number, variety, and variability of organisms. It includes diversity within species (Le., genetic and morphological), between species (Le., alpha and beta), and among ecosystems (Le., beta and gamma). Over the past few hundred years, human activities have increased species extinction rates by as much as 1,000 times above the background rates that were typical over Earth's history (Figure 2.1) (Millennium Ecosystem Assessment 2005; but see He and Hubbell 2011). In the United States, there are approximately 1,900 species listed as threatened or endangered, with potentially …

The Inky Story Of The Dinky Oak Gall, Ken Sulak

United States Geological Survey: Staff Publications

Maybe you have noticed these little spheres before – but did not give them much thought. Or maybe, you puzzled: What are these wooden pearls? How did they get there? Well, a tiny wasp, called the pea galler wasp or gallfly, Belonocnema treatae, is the culprit. The diminutive female gallfly (one of nearly a thousand species in the gall wasp family Cynipidae), about the size of a fire ant, lays eggs on a freshly budded live oak leaf in spring. When the larva hatches, it produces a chemical that induces the oak to enclose it in a protective and …

Integrating Land Cover Modeling And Adaptive Management To Conserve Endangered Species And Reduce Catastrophic Fire Risk, David Breininger, Brean Duncan, Mitchell J. Eaton, Fred Johnson, James Nichols

United States Geological Survey: Staff Publications

Land cover modeling is used to inform land management, but most often via a two-step process, where science informs how management alternatives can influence resources, and then, decision makers can use this information to make decisions. A more efficient process is to directly integrate science and decision-making, where science allows us to learn in order to better accomplish management objectives and is developed to address specific decisions. Co-development of management and science is especially productive when decisions are complicated by multiple objectives and impeded by uncertainty. Multiple objectives can be met by the specification of tradeoffs, and relevant uncertainty can …

Coastal Tectonics On The Eastern Margin Of The Pacific Rim: Late Quaternary Sea-Level History And Uplift Rates, Channel Islands National Park, California, Usa, Daniel R. Muhs, Kathleen R. Simmons, R. Randall Schumann, Lindsey T. Groves, Stephen B. Devogel, Scott A. Minor, Deanna Laurel

United States Geological Survey: Staff Publications

The Pacific Rim is a region where tectonic processes play a significant role in coastal landscape evolution. Coastal California, on the eastern margin of the Pacific Rim, is very active tectonically and geomorphic expressions of this include uplifted marine terraces. There have been, however, conflicting estimates of the rate of late Quaternary uplift of marine terraces in coastal California, particularly for the northern Channel Islands. In the present study, the terraces on San Miguel Island and Santa Rosa Island were mapped and new age estimates were generated using uranium-series dating of fossil corals and amino acid geochronology of fossil mollusks. …

Exposure And Food Web Transfer Of Pharmaceuticals In Ospreys (Pandion Haliaetus): Predictive Model And Empirical Data, Rebecca S. Lazarus, Barnett A. Rattner, Bryan W. Brooks, Bowen Du, Peter C. Mcgowan, Vicki S. Blazer, Mary Ann Ottinger

United States Geological Survey: Staff Publications

The osprey (Pandion haliaetus) is a well‐known sentinel of environmental contamination, yet no studies have traced pharmaceuticals through the water–fish–osprey food web. A screening‐level exposure assessment was used to evaluate the bioaccumulation potential of 113 pharmaceuticals and metabolites, and an artificial sweetener in this food web. Hypothetical concentrations in water reflecting “wastewater effluent dominated” or “dilution dominated” scenarios were combined with pH‐specific bioconcentration factors (BCFs) to predict uptake in fish. Residues in fish and osprey food intake rate were used to calculate the daily intake (DI) of compounds by an adult female osprey. Fourteen pharmaceuticals and a drug …

Development And Evaluation Of High Resolution Simulation Tools To Improve Fire Weather Forecasts, Brian K. Lamb, Jason M. Forthofer, Peter R. Robichaud

Joint Fire Science Program Research Project Reports

Fire weather forecasts rely on numerical weather simulations where the grid size is 4 km x 4 km or larger. In areas of complex terrain, this model resolution will not capture the details of wind flows associated with complicated topography. Wind channeling in valleys, wind speed-up over mountains and ridges, and enhanced turbulence associated with rough terrain and tall forest canopies are poorly represented in current weather model applications. A number of numerical wind flow models have been developed for simulating winds at high resolution; however, there are limited observational data available at the spatial scales appropriate for evaluating these …

Exploring How Deliberation On Scientific Information Shapes Stakeholder Perceptions Of Forest Management And Climate Change, Troy E. Hall, Jarod J. Blades

Joint Fire Science Program Research Project Reports

Climate change has resulted in rapid biophysical changes in forests of the western U.S. and has prompted the need for an increased understanding of potential impacts and adaption measures. Land managers, policy makers, and community officials lack locally relevant climate change science and are urgently calling for research to inform management decisions. Nevertheless, a substantial disconnect remains between emerging scientific information and its application in management decisions. Effective action depends on understanding regional and local implications of climate change and open, reasoned discussions about current research and potential mitigation actions among researchers, land managers, and other stakeholders. Boundary objects have …

Fire Effects On Seedling Establishment Success Across Treeline: Implications For Future Tree Migration And Flammability In A Changing Climate, F. S. Chapin Iii, Teresa N. Hollingsworth, Rebecca E. Hewitt

Joint Fire Science Program Research Project Reports

Understanding the complex mechanisms controlling treeline advance or retreat in the arctic and subarctic has important implications for projecting ecosystem response to changes in climate. Changes in landcover due to a treeline biome shift would alter climate feedbacks (carbon storage and energy exchange), ecosystem services such as wildlife and berry habitat, and landscape flammability. Wildfire frequency and extent has increased in the last half-century in the boreal forest and tundra in response to warmer weather and lower precipitation. Invasion of tundra by trees may be facilitated by wildfire disturbance, which exposes new seedbeds, increases nutrient availability immediately post-fire, and creates …

Annual Patterns And Budget Of Co2 Flux In An Arctic Tussock Tundra Ecosystem, Walter C. Oechel, Cheryl A. Laskowski, George Burba, Beniamino Gioli, Aram A. M. Kalhori

School of Natural Resources: Faculty Publications

The functioning of Arctic ecosystems is not only critically affected by climate change, but it also has the potential for major positive feedback on climate. There is, however, relatively little information on the role, patterns, and vulnerabilities of CO₂ fluxes during the nonsummer seasons in Arctic ecosystems. Presented here is a year-round study of CO₂ fluxes in an Alaskan Arctic tussock tundra ecosystem, and key environmental controls on these fluxes. Important controls on fluxes vary by season. This paper also presents a new empirical quantification of seasons in the Arctic based on net radiation. The fluxes were computed …

Land Cover Changes And Their Biogeophysical Effects On Climate, Rezaul Mahmood, Roger A. Pielke Sr., Kenneth Hubbard, Dev Niyogi, Paul Dirmeyer, Clive Mcalpine, Andrew Carleton, Robert Hale, Samuel Gameda, Adriana Beltran-Przekurat, Bruce Baker, Richard Mcnider, David R. Legates, Marshall Shepherd, Jinyang Du, Peter D. Blanken, Oliver W. Frauenfeld, U. S. Nair, Souleymane Fall

School of Natural Resources: Faculty Publications

Land cover changes (LCCs) play an important role in the climate system. Research over recent decades highlights the impacts of these changes on atmospheric temperature, humidity, cloud cover, circulation, and precipitation. These impacts range from the local- and regional-scale to sub-continental and global-scale. It has been found that the impacts of regional-scale LCC in one area may also be manifested in other parts of the world as a climatic teleconnection. In light of these findings, this article provides an overview and synthesis of some of the most notable types of LCC and their impacts on climate. These LCC types include …

Sampling For Effective Ex Situ Plant Conservation, Edward O. Guerrant Jr., Kayri Havens, Pati Vitt

Environmental Science and Management Faculty Publications and Presentations

Sampling a whole flora or any significant subset for ex situ conservation purposes is a complex, long-term proposition. Thus, it is important to consider what constitutes an adequate sample not only for all taxa as a whole but also for each taxon individually as well as how to strategically schedule collection over time. There are five basic sampling questions: from which species to collect, from how many and which populations, from how many and which individuals, how many and what kind of propagules to collect, and, finally, at what point is the desired sample size too great for a population …

Droughtscape, Winter 2014, Kelly Smith

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

Contents

Director’s report

Outlook & quarterly review . 2

Drought in 2013 review.

Quarterly impacts review . 5

Impacts in 2013 review.

Belmont Forum research0

USDM change maps 11

Central Asia drought planning

Kansas RC&D planning

Publication compares plans

Drought for planners webinar

Soil moisture networks

Kansas farm and ranch planning

$500 to develop leadership

Kids seek solutions

Plains symposium April 1-4

Plant Community Composition And Structure Monitoring For Agate Fossil Beds National Monument, 2013 Annual Report, Isabel W. Ashton, Michael Prowatzke

United States National Park Service: Publications

Introduction

During the last century, much of the prairie within the Northern Great Plains has been plowed for cropland, planted with non-natives to maximize livestock production, or otherwise developed, making it one of the most threatened ecosystems in the United States. Within Nebraska, greater than 77% of the area of native mixed-grass prairie has been lost since European settlement (Samson and Knopf 1994). The National Park Service (NPS) plays an important role in preserving and restoring some of the last pieces of intact prairies within its boundaries. The stewardship goal of the NPS is to “preserve ecological integrity and cultural …

The Effect Of Azo Textile Dyes On Gross Primary Production And Community Respiration In An Artificial Environment, Theresa L. Petzoldt

Honors Theses

Azo dyes are the largest category of textile dyes in production today, with over 100,000 tons of dye produced yearly in the United States. Ten to fifty percent of this dye is not fixed to the fabric during the textile production process, and is therefore discarded as effluent. Because dye waste is difficult to process in wastewater treatment facilities, it is important to understand how this waste affects aquatic systems using a whole ecosystem approach. This study used an artificial stream to model the effects of four azo dyes on benthic biofilm production and respiration. Dyes were found to have …

The Impact Of Dams On Nitrogen Cycling In The Messalonskee Stream, Rebecca K. Forgrave

Honors Theses

The Messalonskee Stream in central Maine has five hydroelectric dams on 16.6km. Each dam drastically changes the flow regime of the stream, dividing it into segments with different patterns of sediment settling and organic matter retention. I investigated how these disruptions impact nitrogen cycling, specifically nitrification rates above and below each dam. I expected higher nitrification rates above the dams, where levels of organic matter are higher, and lower rates below the dam where scouring removes organic matter and fine sediment from the streambed. I measured sediment nitrification rates with a nitrapyrin-inhibition assay and potential drivers of nitrification including sediment …

Closing The Knowing-Doing Gap In Invasive Plant Management: Accessibility And Interdisciplinarity Of Scientific Research, Virginia Matzek, Justin Covino, Jennifer L. Funk, Martin Saunders

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Like many conservation disciplines, invasion biology may suffer from a knowing-doing gap, where scientific research fails to inform management actions. We surveyed California resource managers to evaluate engagement with scientific research and to identify research priorities. We examined managers' access to information, judgment of the usefulness of existing research, ability to generate scientific information, and priorities for future research. We found that practitioners rely on their own experience, and largely do not read the peer-reviewed literature, which they regard as only moderately useful. Less than half of managers who do research carry out experiments conforming to the norms of hypothesis …