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Laguncularia Racemosa Top-Layer Sediment Microorganism Makeup In Relation To Differing Levels Of Perceived Anthropogenic Impact In Bocas Del Drago, Bocas Del Toro, Panama, Gabrielle Glendening Oct 2022

Laguncularia Racemosa Top-Layer Sediment Microorganism Makeup In Relation To Differing Levels Of Perceived Anthropogenic Impact In Bocas Del Drago, Bocas Del Toro, Panama, Gabrielle Glendening

Independent Study Project (ISP) Collection

As mangrove forests are destroyed by human factors across the earth, many crucial ecological processes that take place in these systems of trees are obstructed. One of the most important roles played by mangroves is their ability to sequester carbon in the sediment, as this storage of carbon helps diminish atmospheric warming. Many sediment microorganisms help in this process of carbon sequestration and play various other vital roles in mangrove ecosystems. Microorganisms in marine sediments can be used to assess the health of the surrounding environment. Past research has found significant differences in sediment microorganism composition, abundance, and diversity in …

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Intact Polar Brgdgts In Arctic Lake Catchments: Implications For Lipid Sources And Paleoclimate Applications, Jonathan H. Raberg, Edgart Flores, Sarah E. Crump, Greg De Wet, Nadia Dildar, Gifford H. Miller, Áslaug Geirsdóttir, Julio Sepúlveda Oct 2022

Intact Polar Brgdgts In Arctic Lake Catchments: Implications For Lipid Sources And Paleoclimate Applications, Jonathan H. Raberg, Edgart Flores, Sarah E. Crump, Greg De Wet, Nadia Dildar, Gifford H. Miller, Áslaug Geirsdóttir, Julio Sepúlveda

Geosciences: Faculty Publications

Paleotemperature histories derived from lake sediment archives provide valuable context for modern and future climate changes. Branched glycerol dialkyl glycerol tetraether (brGDGT) lipids are a valuable tool in such pursuits due to their empirical correlation with temperature and near ubiquity in nature. However, the relative contributions of terrestrial and lacustrine sources of brGDGTs to lake sediments is site-dependent and difficult to constrain. Here, we explored the potential for intact brGDGTs—the complete lipids with polar head groups (HGs) still attached—to provide insight into the sources of brGDGTs on the landscape and their contributions to the sedimentary record in a set of …

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Evaluating The Impact Of Submarine Groundwater Discharge On Nutrients And Trace Elements In Coastal Systems: The Examples Of The Tuckean Swamp (Australia) And The Mississippi Sound (Usa), Amy Moody Oct 2022

Evaluating The Impact Of Submarine Groundwater Discharge On Nutrients And Trace Elements In Coastal Systems: The Examples Of The Tuckean Swamp (Australia) And The Mississippi Sound (Usa), Amy Moody

Dissertations

Submarine groundwater discharge (SGD) is the advective flow of both fresh terrestrial groundwater and recirculating seawater through aquifer sediments, which is released into the coastal ocean. In this dissertation, I evaluated the impact of SGD on the distributions and input of trace metals and nutrients. In the Tuckean Swamp, an estuary in Australia dominated by coastal acid sulfate soils, I determined the impact of groundwater on Ba and U during the flood season, when the local aquifer is flushed out after a rapid increase in water table elevation. For Ba and U, groundwater contributed up to 18 and 66 % …

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Permafrost And Climate Change: Carbon Cycle Feedbacks From The Warming Arctic, Edward A. G. Schuur, Benjamin W. Abbott, Roisin Commane, Jessica G. Ernakovich, Eugenie Euskirchen, Gustaf Hugelius, Guido Grosse, Miriam Jones, Charlie Koven, Victor Leshyk, David Lawrence, Michael M. Loranty, Marguerite Mauritz, David Olefeldt, Susan Natali, Heidi Rodenhizer, Verity Salmon, Christina Schadel, Jens Strauss, Claire C. Treat, Merritt Turetsky Oct 2022

Permafrost And Climate Change: Carbon Cycle Feedbacks From The Warming Arctic, Edward A. G. Schuur, Benjamin W. Abbott, Roisin Commane, Jessica G. Ernakovich, Eugenie Euskirchen, Gustaf Hugelius, Guido Grosse, Miriam Jones, Charlie Koven, Victor Leshyk, David Lawrence, Michael M. Loranty, Marguerite Mauritz, David Olefeldt, Susan Natali, Heidi Rodenhizer, Verity Salmon, Christina Schadel, Jens Strauss, Claire C. Treat, Merritt Turetsky

Faculty Publications

Rapid Arctic environmental change affects the entire Earth system as thawing permafrost ecosystems release greenhouse gases to the atmosphere. Understanding how much permafrost carbon will be released, over what time frame, and what the relative emissions of carbon dioxide and methane will be is key for understanding the impact on global climate. In addition, the response of vegetation in a warming climate has the potential to offset at least some of the accelerating feedback to the climate from permafrost carbon. Temperature, organic carbon, and ground ice are key regulators for determining the impact of permafrost ecosystems on the global carbon …

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Evaluation Of Enzymatic Activity During Growth Of Pleurotus Hk 37 On Saba Comorensis Exocarp, Isse I. Molobele, Rose J. Masalu, Prosper R. Mosha, Cyprian B. Mpinda Sep 2022

Evaluation Of Enzymatic Activity During Growth Of Pleurotus Hk 37 On Saba Comorensis Exocarp, Isse I. Molobele, Rose J. Masalu, Prosper R. Mosha, Cyprian B. Mpinda

Tanzania Journal of Science

Mushrooms degrade lignocellulosic biomass by releasing lignolytic and hydrolytic enzymes which convert lignocellulosic material into soluble and low molecular weight compounds which are then absorbed as nutrients. In the present study, enzymatic activities of Pleurotus HK 37 during growth on Saba comorensis exocarps were evaluated. It was observed that, Pleurotus HK 37 has ability to produce lignolytic enzyme (Laccase) and hydrolytic enzymes (Carboxymethyl cellulase, xylanase and filterpaperase). Maximum laccase activity of 3.33 ± 0 UmL-1 was observed during colonization period and the activity dropped during fruitification phase. Similar to hydrolytic enzymes, the activity was observed during colonization period and decreased …

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Urinary Schistosomiasis And Its Potential For Cancer And Hepato-Renal Function Alterations Among The Residents Of Asejire Dam, South-Western Nigeria, Omowumi O. Adewale, Monsurat O. Odebode, Maryam O. Mustapha, Oluwatosin A. Adetuyi, Monsuru A. Adeleke Sep 2022

Urinary Schistosomiasis And Its Potential For Cancer And Hepato-Renal Function Alterations Among The Residents Of Asejire Dam, South-Western Nigeria, Omowumi O. Adewale, Monsurat O. Odebode, Maryam O. Mustapha, Oluwatosin A. Adetuyi, Monsuru A. Adeleke

Tanzania Journal of Science

Urinary schistosomiasis is of public health significance in sub-Saharan Africa with its prevalence being linked to carcinogenesis. However, there is a paucity of data to support this relationship. This study explored the prevalence and intensity of Schistosoma haematobium infections and its associations with cancer and hepatorenal function alterations in villages along the Asejire dam in the State of Osun, Nigeria. Urine samples from 152 consented participants (aged 18–75 years) from four communities were collected and examined for Schistosoma haematobium using the microscopy method. The blood serum of randomly selected infected and non-infected individuals (10 per group) was screened for tumor, …

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Effects Of Small-Scale Mining Activities On Fisheries And Livelihoods In The Birim River In Atiwa District, Eastern Region Of Ghana, Elliot Haruna Alhassan, Samuel Opoku Dandi, Sandra Akugpoka Atindana Sep 2022

Effects Of Small-Scale Mining Activities On Fisheries And Livelihoods In The Birim River In Atiwa District, Eastern Region Of Ghana, Elliot Haruna Alhassan, Samuel Opoku Dandi, Sandra Akugpoka Atindana

Tanzania Journal of Science

The socioeconomic importance of small-scale mining in Ghana is of great interest to the country. It provides employment, supports the livelihood of poor rural areas, and also contributes to national income. Despite all these importance, it has a great influence on the surroundings, with surface and groundwater bodies being the most affected. The study was conducted to determine the effects of small-scale mining activities on fisheries and livelihoods along the Birim River in Atiwa District of Ghana, and also, to ascertain the nature of mining in the catchment and the current status of fisheries in the river. Data were collected …

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Drivers Of Pb, Sb And As Release From Spent Gunshot In Wetlands: Enhancement By Organic Matter And Native Microorganisms, Anna Potysz, Łukasz J. Binkowski, Jakub Kierczak, Barnett A. Rattner Sep 2022

Drivers Of Pb, Sb And As Release From Spent Gunshot In Wetlands: Enhancement By Organic Matter And Native Microorganisms, Anna Potysz, Łukasz J. Binkowski, Jakub Kierczak, Barnett A. Rattner

United States Geological Survey: Staff Publications

In many countries the use of lead-based ammunition is prevalent, and results in exposure and poisoning of waterfowl and other species of birds. In waterfowl hunting areas large quantities of spent shot may be deposited in wetland and terrestrial habitats. These pellets can undergo transformations, which are influenced by various abiotic and biotic factors. In addition to lead (Pb), other elements like antimony (Sb) and arsenic (As) can be leached from Pb shot into the environment. In vitro simulations that included organic matter and microorganisms were utilized to examine elemental leaching from gunshot. We found that leaching efficiency was the …

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Very High Middle Miocene Surface Productivity On The U.S. Mid-Atlantic Shelf Amid Glacioeustatic Sea Level Variability, Marci M. Robinson, Harry J. Dowsett, Timothy D. Herbert Sep 2022

Very High Middle Miocene Surface Productivity On The U.S. Mid-Atlantic Shelf Amid Glacioeustatic Sea Level Variability, Marci M. Robinson, Harry J. Dowsett, Timothy D. Herbert

United States Geological Survey: Staff Publications

The Miocene Climatic Optimum (MCO) provides important insights into how the climate system operates under elevated temperatures and atmospheric CO2 levels. Few western North Atlantic paleotemperature or paleoecological records exist from the MCO, despite their importance for understanding both regional and global climate dynamics. Here we present quantitative MCO paleoecological data from the western North Atlantic, specifically from the Baltimore Gas & Electric (BG&E) marine sediment core from southern Maryland, USA. We examine alkenones and planktic foraminifera and document the first sea surface temperature (SST) and productivity estimates for the MCO and the Middle Miocene Climate Transition (MMCT) from …

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Establishment Of Invasive Black Carp (Mylopharyngodon Piceus) In The Mississippi River Basin: Identifying Sources And Year Classes Contributing To Recruitment, Gregory W. Whitledge, Patrick T. Kroboth, Duane C. Chapman, Quinton E. Phelps, Wes Sleeper, Jennifer Bailey, Jill A. Jenkins Sep 2022

Establishment Of Invasive Black Carp (Mylopharyngodon Piceus) In The Mississippi River Basin: Identifying Sources And Year Classes Contributing To Recruitment, Gregory W. Whitledge, Patrick T. Kroboth, Duane C. Chapman, Quinton E. Phelps, Wes Sleeper, Jennifer Bailey, Jill A. Jenkins

United States Geological Survey: Staff Publications

Black Carp (Mylopharyngodon piceus) was imported to the USA to control aquaculture pond snails. This species has escaped captivity and occurs in parts of the Mississippi River, several tributaries, and floodplain lakes, which is concerning due to potential competition with native fishes and predation on native mussels, many of which are imperiled. However, Black Carp captures have primarily been incidental by commercial fishers, and evidence of reproduction in the wild is limited. The objectives of this study were to assess relative abundance of aquaculture- origin and wild Black Carp using ploidy and otolith stable isotope analysis, identify spatial …

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Multi-Omics Responses In Tree Swallow (Tachycineta Bicolor) Nestlings From The Maumee Area Of Concern, Maumee River, Ohio, Chi Yen Tseng, Christine M. Custer, Thomas W. Custer, Paul M. Dummer, Natalie Karouna-Renier, Cole W. Matson Sep 2022

Multi-Omics Responses In Tree Swallow (Tachycineta Bicolor) Nestlings From The Maumee Area Of Concern, Maumee River, Ohio, Chi Yen Tseng, Christine M. Custer, Thomas W. Custer, Paul M. Dummer, Natalie Karouna-Renier, Cole W. Matson

United States Geological Survey: Staff Publications

A multi-omics approach was utilized to identify altered biological responses and functions, and to prioritize contaminants to assess the risks of chemical mixtures in the Maumee Area of Concern (AOC), Maumee River, OH, USA. The Maumee AOC is designated by the United States Environmental Protection Agency as having significant beneficial use impairments, including degradation of fish and wildlife populations, bird or animal deformities or reproduction problems, and loss of fish and wildlife habitat. Tree swallow (Tachycineta bicolor) nestlings were collected at five sites along the Maumee River, which included wastewater treatment plants (WWTPs) and industrial land-use sites. Polychlorinated …

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A Systematic Review And Meta-Analysis Of The Direct Effects Of Nutrients On Corals, Eileen M. Nalley, Lillian J. Tuttle, Emily E. Conklin, Alexandria L. Barkman, Devynn M. Wulstein, Madeline C. Schmidbauer, Megan J. Donahue Sep 2022

A Systematic Review And Meta-Analysis Of The Direct Effects Of Nutrients On Corals, Eileen M. Nalley, Lillian J. Tuttle, Emily E. Conklin, Alexandria L. Barkman, Devynn M. Wulstein, Madeline C. Schmidbauer, Megan J. Donahue

United States Geological Survey: Staff Publications

Chronic exposure of coral reefs to elevated nutrient conditions can modify the performance of the coral holobiont and shift the competitive interactions of reef organisms. Many studies have nowquantified the links between nutrients and coral performance, but fewhave translated these studies to directly address coastal water quality standards. To address this management need, we conducted a systematic review of peer-reviewed studies, public reports, and gray literature that examined the impacts of dissolved inorganic nitrogen (DIN: nitrate, nitrite, and ammonium) and dissolved inorganic phosphorus (DIP: phosphate) on scleractinian corals. The systematic review resulted in 47 studies with comparable data on coral …

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Transcriptome Signatures Of Wastewater Effluent Exposure In Larval Zebrafish Vary With Seasonal Mixture Composition In An Effluent-Dominated Stream, Emma B. Meade, Luke R. Iwanowicz, Nicklaus Neureuther, Gregory H. Lefevre, Dana W. Kolpin, Hui Zhi, Shannon M. Meppelink, Rachael F. Lane, Angela Schmoldt, Aurash Mohaimani, Olaf Mueller, Rebecca D. Klaper Sep 2022

Transcriptome Signatures Of Wastewater Effluent Exposure In Larval Zebrafish Vary With Seasonal Mixture Composition In An Effluent-Dominated Stream, Emma B. Meade, Luke R. Iwanowicz, Nicklaus Neureuther, Gregory H. Lefevre, Dana W. Kolpin, Hui Zhi, Shannon M. Meppelink, Rachael F. Lane, Angela Schmoldt, Aurash Mohaimani, Olaf Mueller, Rebecca D. Klaper

United States Geological Survey: Staff Publications

Wastewater treatment plant (WWTP) effluent-dominated streams provide critical habitat for aquatic and terrestrial organisms but also continually expose them to complex mixtures of pharmaceuticals that can potentially impair growth, behavior, and reproduction. Currently, few biomarkers are available that relate to pharmaceutical-specific mechanisms of action. In the experiment reported in this paper, zebrafish (Danio rerio) embryos at two developmental stages were exposed to water samples from three sampling sites (0.1 km upstream of the outfall, at the effluent outfall, and 0.1 km below the outfall) during base-flow conditions from two months (January and May) of a temperate-region effluent-dominated stream …

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Speleothems In Sandstone Crevice And Boulder Caves Of The Elbe River Canyon, Czech Republic, Jiří Adamovič, Jaroslav Kukla, Michal Filippi, Roman Skála, Noemi Mészárosová Sep 2022

Speleothems In Sandstone Crevice And Boulder Caves Of The Elbe River Canyon, Czech Republic, Jiří Adamovič, Jaroslav Kukla, Michal Filippi, Roman Skála, Noemi Mészárosová

International Journal of Speleology

A variety of speleothems are present in crevice and boulder caves developed in Cretaceous sandstones of the Elbe River Canyon in northern Czech Republic. A set of complementary instrumental mineralogical methods was applied to characterize the speleothems and cave dripwaters, including X-ray powder diffraction, scanning electron microscopy and microanalysis, Raman spectroscopy and optical emission spectrometry. Four morphological types were distinguished and characterized in terms of their mineral and chemical composition: 1, rusty brown mud-dominated coatings with micro-gours, composed of a mixture of clay minerals; 2, white “chalky” coatings (moonmilk) composed of calcite with minor gypsum; 3, cauliflower-shaped coralloids composed of …

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Using Whole-Brain Diffusion Tensor Analysis To Evaluate White Matter Structural Correlates Of Delayed Visuospatial Memory And One-Week Motor Skill Retention In Nondemented Older Adults: A Preliminary Study, Jennapher Lingo Vangilder, Maurizio Bergamino, Andrew Hooyman, Megan C. Fitzhugh, Corianne Rogalsky, Jill C. Stewart, Scott C. Beeman, Sydney Y. Schaefer Sep 2022

Using Whole-Brain Diffusion Tensor Analysis To Evaluate White Matter Structural Correlates Of Delayed Visuospatial Memory And One-Week Motor Skill Retention In Nondemented Older Adults: A Preliminary Study, Jennapher Lingo Vangilder, Maurizio Bergamino, Andrew Hooyman, Megan C. Fitzhugh, Corianne Rogalsky, Jill C. Stewart, Scott C. Beeman, Sydney Y. Schaefer

Faculty Publications

Skill retention is important for motor rehabilitation outcomes. Recent work has demonstrated that delayed visuospatial memory performance may predict motor skill retention in older and neuropathological populations. White matter integrity between parietal and frontal cortices may explain variance in upper-extremity motor learning tasks and visuospatial processes. We performed a whole-brain analysis to determine the white matter correlates of delayed visuospatial memory and one-week motor skill retention in nondemented older adults. We hypothesized that better frontoparietal tract integrity would be positively related to better behavioral performance. Nineteen participants (age>58) completed diffusion-weighted imaging, then a clinical test of delayed visuospatial memory …

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Enrofloxacin And Sulfamethoxazole Sorption On Carbonized Leonardite: Kinetics, Isotherms, Influential Effects, And Antibacterial Activity Toward S. Aureus Atcc 25923, Chanat Chokejaroenrat, Chainarong Sakulthaew, Khomson Satchasataporn, Daniel D. Snow, Tarik E. Ali, Mohammed A. Assiri, Apichon Watcharenwong, Saksit Imman, Nopparat Suriyachai, Torpong Kreetachat Sep 2022

Enrofloxacin And Sulfamethoxazole Sorption On Carbonized Leonardite: Kinetics, Isotherms, Influential Effects, And Antibacterial Activity Toward S. Aureus Atcc 25923, Chanat Chokejaroenrat, Chainarong Sakulthaew, Khomson Satchasataporn, Daniel D. Snow, Tarik E. Ali, Mohammed A. Assiri, Apichon Watcharenwong, Saksit Imman, Nopparat Suriyachai, Torpong Kreetachat

Nebraska Water Center: Faculty Publications

Excessive antibiotic use in veterinary applications has resulted in water contamination and potentially poses a serious threat to aquatic environments and human health. The objective of the current study was to quantify carbonized leonardite (cLND) adsorption capabilities to remove sulfamethoxazole (SMX)- and enrofloxacin (ENR)-contaminated water and to determine the microbial activity of ENR residuals on cLND following adsorption. The cLND samples prepared at 450oC and 850oC (cLND450 and cLND550, respectively) were evaluated for structural and physical characteristics and adsorption capabilities based on adsorption kinetics and isotherm studies. The low pyrolysis temperature of cLND resulted in a …

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The Effects Of Estradiol-17Β On The Sex Reversal, Survival, And Growth Of Green Sunfish Lepomis Cyanellus, Chad N. Teal, Daniel J. Schill, Susan B. Fogelson, Colby M. Roberts, Kevin Fitzsimmons, Javan M. Bauder, William T. Stewart, Scott A. Bonar Sep 2022

The Effects Of Estradiol-17Β On The Sex Reversal, Survival, And Growth Of Green Sunfish Lepomis Cyanellus, Chad N. Teal, Daniel J. Schill, Susan B. Fogelson, Colby M. Roberts, Kevin Fitzsimmons, Javan M. Bauder, William T. Stewart, Scott A. Bonar

United States Geological Survey: Staff Publications

The feminization of green sunfish Lepomis cyanellus could expand their utility as a game fish or aquacultured species by preventing overcrowding and precocious reproduction in stocked systems. Feminization of green sunfish could also help elucidate information on their sex determination system. We report the feminization of green sunfish cohorts via oral administration of estradiol-17β (E2) during early development. A low-dose (100 E2 mg per kg of diet) and a high-dose (150 E2 mg per kg of diet) experimental E2 treatment were fed to juvenile green sunfish from 30 to 90 days post-hatch. Fish were subsequently evaluated for any treatment effect …

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Climate Change Alters Aging Patterns Of Reservoir Aquatic Habitats, Leandro E. Miranda, Nicky M. Faucheux Sep 2022

Climate Change Alters Aging Patterns Of Reservoir Aquatic Habitats, Leandro E. Miranda, Nicky M. Faucheux

United States Geological Survey: Staff Publications

Two slow-moving developments are threatening reservoir aquatic habitats globally: aging and climate change. These events are projected to transform reservoir aquatic habitats in various and often unpredictable ways. Aging affects in-lake habitats directly, whereas climate change affects both in-lake and off-lake conditions. Climate change is expected to accelerate and, in some instances, possibly decelerate aging. Aging can be indexed as functional age, an index that signals the position of a reservoir along its lifespan relying on inlake descriptors of aquatic habitat. Using existing habitat datasets and climate projections, we developed semi-quantitative predictions about the effect of climate change on reservoir …

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Recovery Of Soil Microbial Diversity And Functions Along A Tropical Montane Forest Disturbance Gradient, Renee Sniegocki, Jessica B. Moon, Abigail L. Rutrough, Jude Gireneus, Jaya Seelan Sathiya Seelan, Michael C. Farmer, David C. Weindorf, Kusum Naithani Sep 2022

Recovery Of Soil Microbial Diversity And Functions Along A Tropical Montane Forest Disturbance Gradient, Renee Sniegocki, Jessica B. Moon, Abigail L. Rutrough, Jude Gireneus, Jaya Seelan Sathiya Seelan, Michael C. Farmer, David C. Weindorf, Kusum Naithani

Biological Sciences Faculty Publications and Presentations

Logging and forest conversion are occurring at alarming rates in tropical forests. These disturbances alter soil microbial community structure and functions. While direct links between changes in soil properties, such as pH and microbial community structure are well established, the indirect effects of logging and forest conversion on soil microbial community structure and functions are poorly understood. We used a space-for-time substitution to investigate the changes in soil microbial diversity and functions across a forest recovery gradient in the tropical montane forests of northern Borneo. We used surface (top 5 cm) soil to assess soil physicochemical and microbial (next-generation DNA …

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Permafrost Landscape History Shapes Fluvial Chemistry, Ecosystem Carbon Balance, And Potential Trajectories Of Future Change, Scott Zolkos, Suzanne E. Tank, Steven V. Kokelj, Robert G. Striegl, Sarah Shakil, Carolina Voigt, Oliver Sonnentag, William L. Quinton, Edward A.G. Schuur, Donatella Zona, Peter M. Lafleur, Ryan C. Sullivan, Masahito Ueyama, David Billesbach, David Cook, Elyn R. Humphreys, Philip Marsh Sep 2022

Permafrost Landscape History Shapes Fluvial Chemistry, Ecosystem Carbon Balance, And Potential Trajectories Of Future Change, Scott Zolkos, Suzanne E. Tank, Steven V. Kokelj, Robert G. Striegl, Sarah Shakil, Carolina Voigt, Oliver Sonnentag, William L. Quinton, Edward A.G. Schuur, Donatella Zona, Peter M. Lafleur, Ryan C. Sullivan, Masahito Ueyama, David Billesbach, David Cook, Elyn R. Humphreys, Philip Marsh

Daugherty Water for Food Global Institute: Faculty Publications

Intensifying permafrost thaw alters carbon cycling by mobilizing large amounts of terrestrial substrate into aquatic ecosystems. Yet, few studies have measured aquatic carbon fluxes and constrained drivers of ecosystem carbon balance across heterogeneous Arctic landscapes. Here, we characterized hydrochemical and landscape controls on fluvial carbon cycling, quantified fluvial carbon fluxes, and estimated fluvial contributions to ecosystem carbon balance across 33 watersheds in four ecoregions in the continuous permafrost zone of the western Canadian Arctic: unglaciated uplands, ice-rich moraine, and organic-rich lowlands and till plains. Major ions, stable isotopes, and carbon speciation and fluxes revealed patterns in carbon cycling across ecoregions …

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Vermicompost Versus Traditional Compost Amendments Leads To Different Soil Health Outcomes In A Mediterranean Vineyard, Elizabeth L. Luck Sep 2022

Vermicompost Versus Traditional Compost Amendments Leads To Different Soil Health Outcomes In A Mediterranean Vineyard, Elizabeth L. Luck

Master of Science in Environmental Sciences and Management Projects

Compost application has become a common practice in vineyard management to increase soil and crop health, however, the environmental externalities such as greenhouse gas emissions (GHG) from cropping systems that utilize organic fertilizers, such as compost, is uncertain. Vermicompost, which is compost created through the digestion of organic matter by earthworms, and its related ‘extract’ are commonly thought to provide more benefits for soil and crop health compared to standard compost. However, organic fertilizers such as vermicompost, vermicompost extract, and compost have not been compared in their effects on soil health in Mediterranean vineyards. In this two-year study, I assessed …

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Airborne Snowsar Data At X And Ku Bands Over Boreal Forest, Alpine And Tundra Snow Cover, Hans-Peter Marshall Sep 2022

Airborne Snowsar Data At X And Ku Bands Over Boreal Forest, Alpine And Tundra Snow Cover, Hans-Peter Marshall

Geosciences Faculty Publications and Presentations

The European Space Agency SnowSAR instrument is a side-looking, dual-polarised (VV/VH), X/Ku band synthetic aperture radar (SAR), operable from various sizes of aircraft. Between 2010 and 2013, the instrument was deployed at several sites in Northern Finland, Austrian Alps and northern Canada. The purpose of the airborne campaigns was to measure the backscattering properties of snow-covered terrain to support the development of snow water equivalent retrieval techniques using SAR. SnowSAR was deployed in Sodankylä, Northern Finland, for a single flight mission in March 2011 and 12 missions at two sites (tundra and boreal forest) in the winter of 2011–2012. Over …

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Nsf Supported Socio-Environmental Research: How Do Crosscutting Programs Affect Research Funding, Publication, And Citation Patterns?, Kendra E. Kaiser, Anna E. Braswell, Megan L. Fork Sep 2022

Nsf Supported Socio-Environmental Research: How Do Crosscutting Programs Affect Research Funding, Publication, And Citation Patterns?, Kendra E. Kaiser, Anna E. Braswell, Megan L. Fork

Geosciences Faculty Publications and Presentations

Recognizing the continued human domination of landscapes across the globe, social-ecological systems (SES) research has proliferated, necessitating interdisciplinary collaborations. Although interdisciplinary research started gaining traction in academic settings close to 50 years ago, formal frameworks for SES research did not develop until the late 1990s. The first National Science Foundation (NSF) funding mechanism specifically for interdisciplinary SES research began in 2001 and the SES-specific Coupled Natural Human (CNH) Systems program began in 2007. We used data on funded NSF projects from 2000 to 2015 to examine how SES research was funded, where the research is published, and the scholarly impact …

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Nutrient Dynamics And Ecosystem Development Of Urban Forests, Gisselle A. Mejía Sep 2022

Nutrient Dynamics And Ecosystem Development Of Urban Forests, Gisselle A. Mejía

Dissertations, Theses, and Capstone Projects

Urban growth and expansion are a major component of global environmental change, with impacts on climate, air and water quality, biodiversity, and human well-being. Forests embedded in urban landscapes are critical in mitigating these impacts at local, regional, and continental scales. However, assessing urban forests is difficult because cities are heterogenous in physical, chemical, biological, and social dimensions. This heterogeneity has constrained how urban forests are defined, and therefore, how they are studied. The objective of this dissertation is to determine how these biophysical and social factors drive ecological processes in urban forests and will address three outstanding challenges in …

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Elucidating Thermochemical Pretreatment Effectiveness Of Different Particle-Size Switchgrass For Cellulosic Ethanol Production, Jikai Zhao, Yang Yang, Meng Zhang, Charles W. Rice, Donghai Wang Sep 2022

Elucidating Thermochemical Pretreatment Effectiveness Of Different Particle-Size Switchgrass For Cellulosic Ethanol Production, Jikai Zhao, Yang Yang, Meng Zhang, Charles W. Rice, Donghai Wang

School of Earth, Environmental, & Marine Sciences Faculty Publications

Effects of switchgrass particle sizes (pretreatments were investigated. As particle size increased, glucan, xylan, and lignin contents in raw switchgrass augmented from 30.32% to 32.02%, 18.44% to 19.03%, and 14.78% to 15.33%, respectively. Glucan and xylan (58.54–60.94% and 18.55–20.01%) contents in NaOH pretreated switchgrass and their recoveries (91.95–94.69% and 47.91–52.31%) increased. The highest glucan content (55.76%) and recovery (79.72%) in H2SO4 pretreated switchgrass were reached by middle particle size. The lowest (59.39% for H2SO4 and 58.99% for NaOH) and highest (65.23% for H2SO4 and 66.15% for NaOH) CrI values were obtained from middle and small particle sizes, respectively. …

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Low Soil Nitrogen And Moisture Limit The Expansion Of The Invasive Grass, Megathyrsus Maximus (Guinea Grass) In Semi-Arid Soils, E. Penelope Holland, Vanessa Thomas, Pushpa G. Soti Sep 2022

Low Soil Nitrogen And Moisture Limit The Expansion Of The Invasive Grass, Megathyrsus Maximus (Guinea Grass) In Semi-Arid Soils, E. Penelope Holland, Vanessa Thomas, Pushpa G. Soti

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

The goal of this study was to predict the range expansion potential of an invasive forage grass, Guinea grass (Megathyrsus maximus). We collected rhizosphere soil samples of M. maximus and coexisting species from 150 different locations and analysed them for soil properties. We estimated the probability of M. maximus presence as a function of soil moisture, organic matter, pH, salinity, total N, and CN ratio using logistic regression. Presence of M. maximus was associated with higher soil moisture, higher organic matter, pH, and nitrogen, but lower salinity and CN ratio. Soil nitrogen and moisture …

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Acid Mine Drainage In The Shamokin Creek Watershed: A Spatial Analysis Of Economic And Environmental Consequences Of Coal Mining, Ben Shimer Sep 2022

Acid Mine Drainage In The Shamokin Creek Watershed: A Spatial Analysis Of Economic And Environmental Consequences Of Coal Mining, Ben Shimer

Student Project Reports

No abstract provided.

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Why New Zealand’S Indigenous Reconciliation Process Has Failed To Empower Māori Fishers: Distributional, Procedural, And Recognition-Based Injustices, Hekia Bodwitch, Andrew M. Song, Owen Temby, John Reid, Megan Bailey, Gordon M. Hickey Sep 2022

Why New Zealand’S Indigenous Reconciliation Process Has Failed To Empower Māori Fishers: Distributional, Procedural, And Recognition-Based Injustices, Hekia Bodwitch, Andrew M. Song, Owen Temby, John Reid, Megan Bailey, Gordon M. Hickey

School of Earth, Environmental, & Marine Sciences Faculty Publications

How is it that the New Zealand government’s process for re-establishing Indigenous fishing rights has failed to deliver thriving Māori fisheries? This paper examines why, at Te Waihora, a coastal lake, and site of one of the nation’s longest running and best-funded state-Māori co-governance agreements, Māori fishers have been unable to use their rights to support their fishery. As of 2018, the lake’s culturally and ecologically significant eel population was no longer commercially viable, a decline fishers have attributed to rampant dairy industry expansion upstream. Drawing on environmental justice literatures, we deploy a multi-dimensional framework to identify factors shaping possibilities …

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Irrigation Decisions In Response To Groundwater Salinity In Kansas, Juhee Lee, Nathan P. Hendricks Sep 2022

Irrigation Decisions In Response To Groundwater Salinity In Kansas, Juhee Lee, Nathan P. Hendricks

School of Earth, Environmental, & Marine Sciences Faculty Publications

Understanding the interaction between groundwater salinity and irrigation decision making has important implications for groundwater management. Econometrics models were estimated using observed farmer behavior in response to different groundwater salinity levels in a region of Kansas. Estimation results demonstrate that farmers in the face of groundwater salinity change their irrigation decisions on irrigated acreage (i.e., extensive margin), crop choice (i.e., indirect intensive margin), and water application depth (i.e., direct intensive margin). The empirical results indicate an overall decrease in water use due to higher salinity, primarily through a decrease at the extensive margin.

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Production Of Distilled Spirits Using Grain Sorghum Through Liquid Fermentation, Thomas Weiss, Jikai Zhao, Ruijia Hu, Meicen Liu, Yonghui Li, Yi Zheng, Gordon Smith, Donghai Wang Sep 2022

Production Of Distilled Spirits Using Grain Sorghum Through Liquid Fermentation, Thomas Weiss, Jikai Zhao, Ruijia Hu, Meicen Liu, Yonghui Li, Yi Zheng, Gordon Smith, Donghai Wang

School of Earth, Environmental, & Marine Sciences Faculty Publications

The objectives of this research were to investigate the fermentation performance of US sorghum varieties for the production of distilled spirits as well as their associated coproducts and to study the formation of volatile compounds that are related to the flavor quality of the spirits. Three US sorghum varieties (red, white, and waxy sorghums) and four yeast strains (DADY, Ethanol Red, GR-2, and 71B) were used for distilled spirit production. Both sorghum variety and type of yeast strains had effects on alcohol concentration and alcohol yield. The alcohol concentration varied from 10.26 to 11.34% (v/v) while alcohol yield varied from …

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