Other Environmental Sciences Commons^™

Carbon–Temperature–Water Change Analysis For Peanut Production Under Climate Change: A Prototype For The Agmip Coordinated Climate-Crop Modeling Project (C3mp), Alex Ruane, Sonali Mcdermid, Cynthia Rosenzweig, Guillermo Baigorria, James W. Jones, Consuelo Romero, L. Dewayne Cecil

School of Natural Resources: Faculty Publications

Climate change is projected to push the limits of cropping systems and has the potential to disrupt the agricultural sector from local to global scales. This article introduces the Coordinated Climate-Crop Modeling Project (C3MP), an initiative of the Agricultural Model Intercomparison and Improvement Project (AgMIP) to engage a global network of crop modelers to explore the impacts of climate change via an investigation of crop responses to changes in carbon dioxide concentration ([CO2]), temperature, and water. As a demonstration of the C3MP protocols and enabled analyses, we apply the Decision Support System for Agrotechnology Transfer (DSSAT) CROPGRO-Peanut crop model for …

Assessing Risk Of Disease Transmission: Direct Implications For An Indirect Science, Michael Lavelle, Justin Fischer, Gregory Phillips, Tyler Campbell, Kurt C. Vercauteren, Aaron Hildreth, David Hewiltt, Scott Hygnstrom

School of Natural Resources: Faculty Publications

By definition, contact denotes the ;unction of at least two objects. In the context of disease transmission, contact implies interaction with potential to spread disease. Mischaracterization of contacts may res"lt in inaccurate estimates of transmission rates. To collect more-accurate contact data among white-tailed deer (Odocoileus virginianus), "'e built a deer-borne contact detection system (DCDS) consisting of a camera and a proximity logger installed on a GPS (Global Positioning System) collar. We outfitted 26 adult male deer with DCDSs to record GPS locations, proximity of equipped deer to other equipped deer, and video of deer interactions in southern Texas during arltUmn …

A Tallgrass Prairie Forb In A Landscape Shaped By Patch Burn Grazing, Stephen L. Winter

School of Natural Resources: Faculty Publications

Our research indicated that Indian plantain is a tallgrass prairie forb that experiences a temporary period of competitive release as a result of the fire‐grazing interaction found in patch burn grazing systems. Additional research is needed to determine what other species of perennial forbs exhibit this phenomena and in what other locations. Conservationists are especially interested in whether this is the case for what are termed “conservative” species of forbs, species that aren’t typically found in locations that have a long history of heavy grazing or other type of land use that produces vegetation characterized by only the hardiest species. …

Landsat-8: Science And Product Vision For Terrestrial Global Change Research, David P. Roy, M. A. Wulder, T. R. Loveland, C. E. Woodcock, R. G. Allen, M. C. Anderson, D. Helder, J. R. Irons, D. M. Johnson, R. Kennedy, T. A. Scambos, C. B. Schaaf, J. R. Schott, Y. Sheng, E. F. Vermote, A. S. Belward, R. Bindschadler, W. B. Cohen, F. Gao, J. D. Hipple, P. Hostert, Desert Research Institute, Reno, Nv, C. O. Justice, Ayse Kilic, V. Kovalskyy, Z. P. Lee, L. Lymburner, J. G. Masek, J. Mccorkel, Y. Shuai, R. Trezza, J. Vogelmann, R. H. Wynne, Z. Zhu

School of Natural Resources: Faculty Publications

Landsat 8, a NASA and USGS collaboration, acquires global moderate-resolution measurements of the Earth's terrestrial and polar regions in the visible, near-infrared, short wave, and thermal infrared. Landsat 8 extends the remarkable 40 year Landsat record and has enhanced capabilities including new spectral bands in the blue and cirrus cloud-detection portion of the spectrum, two thermal bands, improved sensor signal-to-noise performance and associated improvements in radiometric resolution, and an improved duty cycle that allows collection of a significantly greater number of images per day. This paper introduces the current (2012–2017) Landsat Science Team's efforts to establish an initial understanding of …

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 …