Digital Commons Network^™

Seasonal Changes Of Mineral Elements In Yak Blood, Herbage And Soil Around Qinghai Lake, X. L. Luo, J. T. Xu, Y. P. Wei, Z. B. Tong, Y. H. Ma, S. M. Chen, Z. J. Ma

IGC Proceedings (1977-2023)

No abstract provided.

Snow-Albedo Feedback In Northern Alaska: How Vegetation Influences Snowmelt, Lucas C. Reckhaus

Theses and Dissertations

This paper investigates how the snow-albedo feedback mechanism of the arctic is changing in response to rising climate temperatures. Specifically, the interplay of vegetation and snowmelt, and how these two variables can be correlated. This has the potential to refine climate modelling of the spring transition season. Research was conducted at the ecoregion scale in northern Alaska from 2000 to 2020. Each ecoregion is defined by distinct topographic and ecological conditions, allowing for meaningful contrast between the patterns of spring albedo transition across surface conditions and vegetation types. The five most northerly ecoregions of Alaska are chosen as they encompass …

Development And Performance Assessment Of An Integrated Vermifiltration Based Treatment System For The Treatment Of Feedlot Runoff, Rajneesh Singh, Matteo D'Alessio, Yulie Meneses, Shannon L. Bartelt-Hunt, Brian Woodbury, Chittaranjan Ray

Nebraska Water Center: Faculty Publications

The objective of this study was to treat feedlot runoff by developing an ecologically sustainable, affordable, and resilient treatment system having a relatively long life span. Three horizontal flow soil biofilters were utilized in this study: 1) without earthworms and plants (Biofilter (BF)), 2) with earthworms only (Vermifilter (VF)), and 3) with earthworms and plants (Macrophyte Assisted Vermifilter (MAVF)). The experiments were conducted with a hydraulic retention time of four days using Lumbricus terestrris earthworms and Carex frankii wetland plants. The average COD removal from the BF, VF, and MAVF were 23.2–30.4%, 61.4–69.1%, and 68.3–78.1%, respectively. Average TN removal efficiencies …

Nitrous Oxide Emissions From Dairy Pasture Systems In New Zealand, Jiafa Luo, S. B. Lindsey, Sterwart F. Ledgard, W. Sun, M. Kear

IGC Proceedings (1977-2023)

No abstract provided.

Effects Of Liming And Nitrogen Application On The Cu, Mn, And Zn Concentrations In Herbage From Extensively Managed Pastures, Harald Laser

IGC Proceedings (1977-2023)

No abstract provided.

Using Climate To Explain And Predict West Nile Virus Risk In Nebraska, Kelly Helm Smith, Andrew J. Tyre, Jeff Hamik, Michael J. Hayes, Yuzhen Zhou, Li Dai

National Drought Mitigation Center: Faculty Publications

We used monthly precipitation and temperature data to give early warning of years with higher West Nile Virus (WNV) risk in Nebraska. We used generalized additive models with a negative binomial distribution and smoothing curves to identify combinations of extremes and timing that had the most influence, experimenting with all combinations of temperature and drought data, lagged by 12, 18, 24, 30, and 36 months. We fit models on data from 2002 through 2011, used Akaike's Information Criterion (AIC) to select the best‐fitting model, and used 2012 as out‐of‐sample data for prediction, and repeated this process for each successive year, …

Imidacloprid Movement Into Fungal Conidia Is Lethal To Mycophagous Beetles, Robin A. Choudhury, Andrew M. Sutherland, Matt J. Hengel, Michael P. Parrella, W. Douglass Gubler

School of Earth, Environmental, & Marine Sciences Faculty Publications

Applications of systemic pesticides can have unexpected direct and indirect effects on nontarget organisms, producing ecosystem-level impacts. We investigated whether a systemic insecticide (imidacloprid) could be absorbed by a plant pathogenic fungus infecting treated plants and whether the absorbed levels were high enough to have detrimental effects on the survival of a mycophagous beetle. Beetle larvae fed on these fungi were used to assess the survival effects of powdery mildew and imidacloprid in a factorial design. Fungal conidia were collected from treated and untreated plants and were tested for the presence and concentration of imidacloprid. The survival of beetles fed …

Collaborative Research: Constraining The Tempo And Dynamics Of Cambrian Earth Systems In Western Laurentia, Carol M. Dehler

Funded Research Records

No abstract provided.

Impacts Of Long‐Term Enclosure On Soil Microbes In Mountain‐Pasture In Bayinbuluke, Ping'an Jiang

IGC Proceedings (1977-2023)

No abstract provided.

Effects Of Phosphate Fertilizer On Regrowth Of Medicago Sativa After Defoliation, Huixin Jiang, Yixin Shen, Guiyu Zhai

IGC Proceedings (1977-2023)

No abstract provided.

Correction Of Sulphur Deficiency On Naturalized Pastures Of Western Patagonia (Chile), Christian Hepp

IGC Proceedings (1977-2023)

No abstract provided.

Variability And Temporal Trends Of Semivolatile Organic Compounds In Biological And Environmental Media, Kyunghoon Kim

Earth & Environmental Sciences Dissertations - Archive

Exposure to semivolatile organic compounds (SVOCs) in indoor environments and its potential impact on human health have been receiving increased public attention, because people in developed countries spend over 80% of their time indoors, SVOC levels are several orders of magnitude higher indoors than outdoors, and many SVOCs have various toxicities and endocrine disrupting potential. Concentrations of SVOCs in biological (e.g., human serum) and environmental (e.g., household dust, indoor air) media can help us better understand human exposure to SVOCs. For example, SVOC concentrations in biological media collected over several years may shed light on temporal trends of exposure due …

Paleoenvironment Reconstruction Of The Eocene Southeastern Tethys Using Geochemistry Of Sedimentary Rocks, Liliana CalderóN Convers

Theses, Dissertations and Culminating Projects

The Early Eocene hyperthermals are a series of transient global warming events that occurred between 54.09 and 52.63 Ma, and are considered as ancient analogues for future climate change. These hyperthermal events are well studied in the deep sea sites, but have not been investigated in the eastern Tethys Ocean. Here, we report new major and trace element geochemistry and stable carbon isotope data of the Early Eocene strata deposited in a shallow marine foreland basin prior to the main stage of India-Asian continent collision at Qumiba section in the Tingri County, southern Tibet. These geochemical data are used to …

Water Quality And Management Challenges In Urban New Jersey, Alessandra Rossi

Theses, Dissertations and Culminating Projects

Exacerbation of extreme weather events and increasing urbanization are facilitating the pathway of pollutants towards the waterbodies with freshwater ecosystems being impacted more than terrestrial and marine ecosystems by anthropogenic stressors. We addressed here the three major threats to freshwater ecosystems, pathogens, litter, and eutrophication, integrating scientific findings with management inputs at the watershed level. We evaluated the relationship between environmental variables measurements and Escherichia coli counts with the intent to develop equations capable of predicting near-real-time E. coli concentrations in two riverine ecosystems to help decision makers in assessments of recreational safety. Results showed that the cumulative rainfall for …

Nitrate Dynamics And Source Within Nested Watersheds Of An Agricultural Stream, Nebraska, Usa, Galen Richards

School of Natural Resources: Dissertations, Theses, and Student Research

Nitrate concentrations have been increasing throughout the globe, primarily due to heightened agricultural activity. Nitrate concentrations in Bazile Creek, located in Northeastern Nebraska, have been steadily rising since the early 2000s. Groundwater nitrate concentrations within the Bazile Creek watershed are high (> 10 mg/L nitrate-N), and there is strong connectivity between groundwater and surface water systems. This study aimed to better understand temporal nitrate concentration variability within the watershed through sampling tributaries and the main channel during baseflow conditions. Nitrate source was also investigated though the use of dual δ¹⁵N and δ¹⁸O nitrate isotopes, with samples …

Evaluating Particulate Matter 2.5 In The Yangtze River Delta, Muhammad Abdullah

Graduate Theses/Dissertations

Particulate Matter 2.5 (PM_2.5) is a growing concern in industrialized countries. In China, high concentrations of PM_2.5 are causing devastating health and environmental effects for the people living there. Coal-burning for domestic and industrial purposes is the main culprit for decreasing air quality in China. The focus of this paper is on the Yangtze River Delta (YRD) located on the eastern coast of China. Hourly PM_2.5 readings from March 2015 to June 2016 were obtained from 125 air quality monitoring stations (AQMS) in 23 cities in the YRD. In this study, PM_2.5 readings were examined …

Statistical Downscaling Techniques To Enhance The Spatial Resolution Of The Grace Satellite Data And To Fill Temporal Gaps, Hossein Sahour

Dissertations

The Gravity Recovery and Climate Experiment (GRACE) has been successfully used to monitor variations in terrestrial water storage (GRACE_TWS ) and groundwater storage (GRACE_GWS) across the globe, yet such applications are hindered on local scales by the limited spatial resolution of GRACE data. Using the Lower Peninsula of Michigan as a test site, I developed optimum procedures to downscale GRACE Release-06 monthly mascon solutions. A four-fold exercise is conducted. Cluster analysis is performed to identify the optimum number and distribution of clusters (areas) of contiguous pixels of similar geophysical signals (GRACE_TWS time series); three clusters are …

Using Terrestrial Laser Scanning To Characterize Peatland Microtopography And Assess Tree Growth Responses To Elevated Temperature And Co2, Jake D. Graham

Boise State University Theses and Dissertations

Northern peatlands are a major terrestrial carbon (C) store, with an annual sink of 0.1 Pg C yr^-1 and a total storage estimate of 547 Pg C. Northern peatlands are also major contributors of atmospheric methane, a potent greenhouse gas. The microtopography of peatlands helps modulate peatland carbon fluxes; however, there is a lack of quantitative characterizations of microtopography in the literature. The lack of formalized schemes to characterize microtopography makes comparisons between studies difficult. Further, many land surface models do not accurately simulate peatland C emissions, in part because they do not adequately represent peatland microtopography and hydrology. …

The Application Of Advanced Technologies For Agriculture And Rangeland Management, Matthew D. Kutugata

Theses and Dissertations

This project demonstrates two applications of remote sensing in agricultural and rangeland environments. In the first, an unmanned aerial system (UAS) equipped with a multi-spectral sensor was used to estimate canopy cover across four different cover crop trials at four time periods. In the second, a local database of stationary camera trap images of wildlife was used to train a convolutional neural network to automatically catalogue images by identifying the animal in those images. Both projects aimed to provide an example of how remote sensing platforms and machine learning techniques can facilitate the rapid collection and processing of large-scale field …

Climate Change And Market-Based Insurance Feedbacks, Eric R. Holley, Adam Liska, Cory Walters, Geoffrey C. Friesen, Michael Hayes, Max J. Rudolph, Donald A. Wilhite

Adam Liska Papers

Climatic events have accounted for 91% of $1.05 trillion in insured costs for global catastrophic events from 1980 to 2016. Costs are driven by socio-economic development and increased frequency and severity of climatic disasters driven by climate change. Government policies to reduce systemic risk (e.g., cap-and-trade, carbon tax) have been a predominant approach for mitigation and adaptation. Alternatively, market-based incentives for climate change adaptation and mitigation already operate via the insurance industry to lessen impacts on society. Insurance feedbacks include changes in 1) premiums and insurance policies, 2) non-coverage, and 3) policy making and litigation. Alongside government policies, insurance feedbacks …

Influence Of Landscape Factors On Wildlife Presence And Road Mitigation Structure Performance, Taylor M. Hopkins

Theses and Dissertations

There are roughly 80 ocelots (Leopardus pardalis) remaining in the United States, with the entire population constrained to south Texas, with roadkill being a predominant source of mortality. To prevent additional roadkill and maintain wildlife movement, Texas Department of Transportation constructed 11.9 kilometers of wildlife exclusion fencing, 5 wildlife crossing structures (WCS), and 18 wildlife guards on State Highway 100. This thesis focused on determining the effort required for a control-impact monitoring study, the influence of biotic and abiotic factors around the roadway on wildlife presence, and the performance of mitigation structures and the road mitigation corridor. This …

Boron In The Pariette Wetlands, Uinta Basin, Ut, Palak Vasudeva

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Boron is a naturally occurring mineral in shale and coal beds formed in marine environments, as found in the Uinta Basin. Mining activity and the application of excess irrigation water on agricultural lands in the Pariette watershed lead to mobilization of B via surface run off. Water quality monitoring records from 2006- 2009 reported violations of Utah B standard for irrigation water 43-100% of the time, for water flowing through the Pariette Wetlands. This study aims to determine B distribution in abiotic (water, sediments) and biotic samples (macroinvertebrates, aquatic vegetation, fish, bird eggs), and to establish correlations between B concentrations …

Effect Of Plant Derived Tannins On Nitrogen And Carbon Cycling In Pasture Soils, Kathryn A. Slebodnik

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Pasture-finished beef has become increasingly popular, but nitrogen losses from these pastures are of concern. Legumes containing condensed tannins such as birdsfoot trefoil (Lotus corniculatus) and sainfoin (Onobrychis viciifolia) may serve as environmentally and economically viable alternative forages in pasture finishing systems while reducing soil nitrogen loss. The goal of this project was to understand how tannin type and concentration affects soil nitrogen cycling both in the lab and the field. This thesis: 1) compared the physical, chemical, and biological characteristics of soil samples obtained from grazed grass and tannin and non-tannin containing legume pastures, 2) …

Paleoenvironmental Reconstruction Of Quaternary Saltville, Virginia, Using Ostracode Autecology, Austin Gause

Electronic Theses and Dissertations

The Saltville valley in southwestern Virginia is home to Quaternary localities containing paleontological and archaeological remains. Historically the valley has been mined for salt and the small lakes, ponds and springs along the valley floor have a brackish signature. A preliminary report on the site’s ostracode fauna suggested that the site’s water was not always saline. This study analyzed modern and Quaternary ostracodes to understand the valley’s hydrologic and chemical evolution. Sediments contained primarily freshwater species, including the environmentally sensitive Candona crogmaniana. The presence of Pelocypris tuberculatum and a new Fabaeformiscandona species throughout a vertical section spanning the latest Pleistocene …

Soil Health Assessment On Arid Rangeland Soils Impacted By Oil And Gas Exploration, Development, And Extraction, Justin Allred

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Oil and gas well pad reclamation in arid environments such as in the Uinta Basin of Utah, presents unique challenges, including remote locations, limited water, and elevated soil salinity and sodicity. Successfully reclaimed Plugged and Abandoned (P&A) well pads should resemble the surrounding rangeland once fully reclaimed. Revegetation of native species is the primary indicator of successful reclamation, but the lack of water makes it challenging to re-seed native plants, while trying to prevent the encroachment of invasive plant species such as Bromus tectorum (cheatgrass), Salsola tragus (Russian thistle), and Halogeton glomeratus (halogeton). Could successful reclamation be reflective of good …

Nitrogen Cycling In Intensively Grazed Pastures And Practices To Reduce Whole‐Farm Nitrogen Losses, Sterwart F. Ledgard, J. Luo

IGC Proceedings (1977-2023)

No abstract provided.

The Monitoring Of Ecological Effect Of Implement Of Sand Control Project In Sand Source Area Round Beijing And Tianjing, Jun Hong, Xujiang Yun, Jie Liu

IGC Proceedings (1977-2023)

No abstract provided.

Statement Of World Aquatic Scientific Societies On The Need To Take Urgent Action Against Human-Caused Climate Change, Based On Scientific Evidence [Dear Colleague Letter], Scott A. Bonar, Brian R. Murphy, Leanne H. Roulson, Jesse T. Trushenski, Douglas J. Austen, Michael Edward Douglas

United States Fish and Wildlife Service: Publications

Dear Colleague Letter from the American Fisheries Society to fellow scientific societies, July 25, 2020, about the urgent need for responsive collective action to mitigate impending radical climate change. Includes the Statement of World Aquatic Scientific Societies on the Need to Take Urgent Action Against Human-Caused Climate Change, Based on Scientific Evidence, emphasizing the importance of aquatic ecosystems. Includes extensive citations and notes.

"Water is the most important natural resource on Earth as it is vital for life. Aquatic ecosystems, freshwater or marine, provide multiple benefits to human society, such as provisioning of oxygen, food, drinking water, genetic resources; regulation …

Geological Factors Impacted Cadmium Availability And Use As An Alternative Cofactor For Zinc In The Carbon Fixation Pathways Of Marine Diatoms, Naman Srivastava, Stephanie J. Spielman, Shaunna M. Morrison, Eli K. Moore

School of Earth & Environment Departmental Research

Transition metal cofactors are crucial for many biological processes. Despite being primarily considered to be toxic, the transition metal cadmium (Cd) was discovered to be a substitute for zinc (Zn) in photosynthetic carbon fixation pathways in marine diatoms. However, it is not known how conditions in the geosphere impacted Cd availability and its incorporation as an alternative metal cofactor for phytoplankton. We employed mineral chemistry network analysis to investigate which geochemical factors may have influenced the availability of Cd and Zn during the putative time period that alternative Cd-based pathway evolved. Our results show that Zn minerals are more chemically …

Effect Of Nitrogen Application On Forage Yield In Alpine Rangeland, Q. P. Zhou, K. J. De, C. T. Xu, Y. J. Ji

IGC Proceedings (1977-2023)

No abstract provided.