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Full-Text Articles in Physical Sciences and Mathematics

An Analysis Of Pollution In Liverpool, Uk, Luke W. Lawson Apr 2024

An Analysis Of Pollution In Liverpool, Uk, Luke W. Lawson

Honors Theses

Within this experiment the different levels of pollution in areas around Liverpool were tested. These areas were Stanley Park, Lunt Meadows, and Woolton Road. At Stanley Park one of two transects had a geochemical analysis as well as magnetic measurements run to investigate source attribution within the urban environment resulting in data showing high variability in soil properties among the transect. With data supporting evidence of diamagnetic, paramagnetic, and ferromagnetic properties in soil along the same transect. At Lunt Meadows, through the use of XRF for soil samples and nitrate and phosphate testing for water samples, it was found that …


Fire Effects On Soil Organic Matter In The Creek Fire, Gracie E. Doolin Sep 2023

Fire Effects On Soil Organic Matter In The Creek Fire, Gracie E. Doolin

Master of Science in Environmental Sciences and Management Projects

Wildfires have increased in frequency and severity over the past few decades due to the increased concertation of CO2 emissions from anthropogenic influence. Soil carbon (C) sequestration has been identified as a climate change mitigation strategy; however, the influx of large-scale wildfires has accelerated landscape processes such as erosion, reducing soil aggradation, and soil C and nitrogen (N) protection. This trend is highlighted by the Creek Fire that occurred in September 2020 and burned 379,895 acres in the Sierra National Forest. This research is designed to close the knowledge gap regarding the impact of burn severity on soil organic matter …


Impacts Of Preferential Flow On Tc-99and Np-237 Vadose Transport In Soils At The Savannah River Site, Josh Parris May 2023

Impacts Of Preferential Flow On Tc-99and Np-237 Vadose Transport In Soils At The Savannah River Site, Josh Parris

All Theses

Since the 1950s, the United States has produced approximately 90,000 metric tons of spent nuclear fuel (SNF) (Office of Nuclear Energy, 2022); however, no long-term storage solutions are available. Technecium-99 and neptunium-237, two fission products found in SNF, readily form highly mobile species in oxidizing conditions (Hu, 2008; Bondietti, 1979) and have respective half-lives of 2.13 x 105 and 2.14 x106 years (Hu, 2010). Considering these characteristics, 99Tc and 237Np are two risk-driving isotopes found in SNF storage. The process of macropore-facilitated preferential flow, transport through cracks within a soil matrix, has been recognized to increase …


Impact Of Cover Crop Species Diversity On Soil Nutrient Availability And Crop Productivity, Amanda Kramer May 2023

Impact Of Cover Crop Species Diversity On Soil Nutrient Availability And Crop Productivity, Amanda Kramer

Masters Theses

Cover crops provide multiple environmental benefits that improve both soil and water quality; however, farmers only utilize them on approximately 5% of harvested U.S. cropland. Low adoption rates are attributed to yield impact concerns, seed and planting costs, and lack of advocacy. This study, which began in October 2019, assessed the effects of nitrogen rate and cover crop diversity on weed biomass, soil coverage, in-situ residue decomposition, soil nitrogen and phosphorus availability, and cash crop yield to better understand the costs and benefits of cover crop adoption at two locations in Tennessee (Milan and Spring Hill). Treatments were replicated 4 …


The Characterization Of Dynamic Soil Properties And Their Relation To Soil Organic Carbon In East Tennessee Soils, Shannon Marissa Newell Aug 2022

The Characterization Of Dynamic Soil Properties And Their Relation To Soil Organic Carbon In East Tennessee Soils, Shannon Marissa Newell

Masters Theses

Quantifying how dynamic soil properties (DSPs) are affected by different management regimes is essential for understanding how these vital resources can be better managed. The Dewey soil series is a critical soil series in East Tennessee. For this study, the University of Tennessee, Knoxville (UTK) worked alongside the National Cooperative Soil Survey (NCSS) in an effort to better understand the dynamics of the Dewey soil series through a wide range of DSP data. To accomplish this, Dewey soil was collected from five sites which are considered representative of five management regimes: well-managed cropland (WMC), poorly-managed cropland (PMC), well-managed pasture (WMP), …


Spatial Geochemical Changes In Central And East Texas Soils Over Time Resulting From Human Decomposition, Isabela Marisol Overturf Jan 2022

Spatial Geochemical Changes In Central And East Texas Soils Over Time Resulting From Human Decomposition, Isabela Marisol Overturf

CMC Senior Theses

Human decomposition is studied to aid forensic investigations and better understand the impact of cemeteries on urban resources like soil and groundwater. The purpose of this study was to identify changes in soil geochemistry at and around a human grave to search for lateral nutrient movement and possibly identify new patterns in elemental concentrations that could be used in estimating post-mortem intervals (PMIs). At the Forensic Anthropology Research Facility (FARF) at Texas State San Marcos, soil samples were collected from a shallow grave over the course of 54 days to conduct analysis for organic matter content, texture, pH, and bulk …


Sediment Production From Forest Roads In Areas Affected By The August Complex Fire In Northern California, Zachary J. Gigone Jan 2022

Sediment Production From Forest Roads In Areas Affected By The August Complex Fire In Northern California, Zachary J. Gigone

Cal Poly Humboldt theses and projects

Wildfire activity is increasing in California and is an important factor affecting erosion rates. Landscapes recently affected by wildfire, areas that have been salvage logged after a fire, and unpaved forest roads are all major sources of sediment which can impair water quality and negatively impact many aquatic species. Therefore, this study was conducted to quantify erosion rates from native and gravel surfaced forest road segments after the August Complex fire, evaluate the impact of salvage logging activities on sediment production from roads, and understand the effect of soil burn severity on sediment production from these road segments. Finally, this …


Evaluation Of Nitrous Oxide Emissions From Furrow-Irrigated Rice On A Silt-Loam Soil In Arkansas, Jordan M. Slayden Dec 2021

Evaluation Of Nitrous Oxide Emissions From Furrow-Irrigated Rice On A Silt-Loam Soil In Arkansas, Jordan M. Slayden

Graduate Theses and Dissertations

As the number one rice (Oryza sativa)-producing state in the United States, Arkansas also ranks fourth as the largest user of groundwater. Recently, due to the development of drought- resistant hybrid cultivars, the furrow-irrigated rice production system has become an increasingly popular alternative to traditional flood-irrigated production with respect to conserving groundwater and maintaining yield. However, other environmental parameters, like greenhouse gas emissions, specifically nitrous oxide (N2O), have yet to be evaluated under furrow-irrigated rice. The objectives of this study were to i) evaluate the effects of site position (i.e., up-, mid-, and down-slope) and tillage treatment [i.e., conventional tillage …


Cover Crop Effects On Near-Surface Soil Aggregate Stability In The Southern Mississippi Valley Loess (Mlra 134), Chandler M. Arel Dec 2021

Cover Crop Effects On Near-Surface Soil Aggregate Stability In The Southern Mississippi Valley Loess (Mlra 134), Chandler M. Arel

Crop, Soil and Environmental Sciences Undergraduate Honors Theses

Intensive agricultural cultivation within major land resource area (MLRA) 134, the Southern Mississippi Valley Loess, has led to soil erosion, soil compaction, and the overall destabilization of near-surface soil aggregates. The use of cover crops during the agricultural offseason has been shown to help alleviate soil compaction and provide stabilizing effects against soil erosion, which are particularly important as the silty soils of MLRA 134 have a large erosion potential. This study evaluated the effects of cover crop and no-cover crop treatment on silt-loam soils within MLRA 134. Treatments were implemented during Fall 2018 and Fall 2019 and consisted of …


Characterization Of Problematic Red Clay Soils In Arkansas For The Purpose Of Onsite Wastewater System Placement, Bailey Darnell May 2021

Characterization Of Problematic Red Clay Soils In Arkansas For The Purpose Of Onsite Wastewater System Placement, Bailey Darnell

Graduate Theses and Dissertations

Distinguishing between red-clay soils that are non-expansive and can reduce and red-clay soils developing in problematic red parent material, which are expansive, but also non-reducing, is key for proper on-site wastewater system placement. The Arkansas Department of Health allows for the placement of on-site wastewater systems in certain red-clay soils that have the potential to reduce, but only in the Ozark Highlands [Major Land Resource Area (MLRA) 116A], which is referred to as the red-soil exception. There is currently little scientific data to support the geographic restriction of the red-soil exception. The objectives of this study were to: i) confirm …


Shaping Soil: Examining Relationships Between Agriculture And Climate Change, Lindsay Barbieri Jan 2021

Shaping Soil: Examining Relationships Between Agriculture And Climate Change, Lindsay Barbieri

Graduate College Dissertations and Theses

As the ripple-effects of a changing climate shape our planet, understanding relationships between agriculture and climate change is critical. With agricultural practices shaping soils on over a third of the earth’s land surface, the soils and lands where food is produced are integral grounds for examining these relationships. While not all humans practice agriculture in similar or damaging ways, nevertheless, dominant agricultural practices are displacing beings and ecosystems and perturbing global nutrient cycles across the planet. These entwined imbalances of dominance and nutrients result in flows of excess nitrogen, phosphorus, and carbon that are responsible for nearly three-fourths of the …


Trace Metal Contamination In Urban Soils: A Field To Laboratory Methodological Framework For Characterization And Education, Sandra Leighanne Walser Jan 2021

Trace Metal Contamination In Urban Soils: A Field To Laboratory Methodological Framework For Characterization And Education, Sandra Leighanne Walser

Graduate College Dissertations and Theses

Urban soils around the world have been found to possess elevated concentrations of toxic trace metals such as As, Cd, Cu, Pb, Mn, Hg, Zn known to pose human health risks. Tightening environmental legislation and further elucidation of the detrimental health impacts from trace metals has necessitated more efficient means of contamination assessment, as well as greater public awareness. Within this thesis, I sought to develop an array of tools to holistically approach the socially relevant environmental challenges derived from heavy metal soil contamination. These tools consist in providing means to simplify Pb, Zn and Cu analysis in-situ, develop strategies …


Investigating Spatial And Temporal Variability Of Environmental And Biological Controls On Riparian Soil Denitrification, Brittany Victoria Lancellotti Jan 2021

Investigating Spatial And Temporal Variability Of Environmental And Biological Controls On Riparian Soil Denitrification, Brittany Victoria Lancellotti

Graduate College Dissertations and Theses

Soil denitrification is a critical component of nitrogen (N) cycling on Earth. It is a microbially-mediated process that removes N from soils by reducing nitrate (NO3-), a highly bioavailable molecule and significant contributor to eutrophication, to gaseous forms of N (N2 or N2O). Riparian areas, which are located at the interface between terrestrial and aquatic ecosystems, are areas of elevated denitrification rates, as they frequently exhibit favorable conditions for this process. Denitrification provides a critical ecosystem service by reducing N inputs to streams and rivers. However, this process is highly variable in time and space, making it difficult to predict …


Correlations Between Soil Redness And Soil Properties That Affect Non-Native Annual Plant Distribution In Chaparral And California Sage Scrub, Madeline Blua Sep 2020

Correlations Between Soil Redness And Soil Properties That Affect Non-Native Annual Plant Distribution In Chaparral And California Sage Scrub, Madeline Blua

Electronic Theses, Projects, and Dissertations

Non-native annual plant species have degraded California Sage Scrub and chaparral and present obstacles to shrubland restoration. Red soil patches in chaparral and California Sage Scrub of San Bernardino and Riverside counties appear to support fewer non-native annual plants than non-red soils. The purpose of this study was to confirm differences in vegetation cover between red and non-red soils in shrublands and to use soil analyses to determine possible causes. During vegetation surveys conducted in April of 2018, it was confirmed that red soil sites had lower cover of non-native plants and higher cover of native plant species than the …


Nematode Populations As Affected By Residue And Water Management In A Long-Term Wheat-Soybean Double Crop In Eastern Arkansas, Lucia Emperatriz Escalante Ortiz Dec 2019

Nematode Populations As Affected By Residue And Water Management In A Long-Term Wheat-Soybean Double Crop In Eastern Arkansas, Lucia Emperatriz Escalante Ortiz

Graduate Theses and Dissertations

Soybeans (Glycine max) are one of the major row crops in the United States, particularly in Arkansas. Soybean cyst nematode (SCN, Heterodera glycines) and southern root-knot nematode (RKN, Meloidogyne incognita) are two of the most damaging pests that cause major economic losses in soybeans. Little is known concerning the effects of common and alternative agronomic practices on nematodes in fields with nematode population densities below threshold levels. Therefore, the objective of this study was to evaluate the effects of the combination of tillage (conventional tillage and no-tillage), irrigation (irrigated and non-irrigated), wheat (Triticum aestivum) residue burning (burned and no burned), …


Environmental Assessment Of Arsenic And Mercury Levels At The Garfield Mill Site, Calico, California, Steven Gregory Thorp Sep 2019

Environmental Assessment Of Arsenic And Mercury Levels At The Garfield Mill Site, Calico, California, Steven Gregory Thorp

Electronic Theses, Projects, and Dissertations

Environmental impacts of mining at Calico, California, are poorly understood in comparison to the details of its history of silver production. Human health risks associated with arsenic from the lode rock, as well as mercury from the silver milling process, include central nervous system damage, organ failure, and death. To quantify the potential human health risk and manage remediation of this site, tailings from the Garfield Mill site were digitally mapped and chemically analyzed by portable x-ray fluorescence, which permitted volumetric estimates of total mill tailings and the arsenic and mercury budget, as well as identification of anomalies in the …


Landuse And Soil Property Effects On Infiltration And Soil Aggregate Stability In The Lower Mississippi River Valley, Rebecca Lynn Anderson May 2019

Landuse And Soil Property Effects On Infiltration And Soil Aggregate Stability In The Lower Mississippi River Valley, Rebecca Lynn Anderson

Graduate Theses and Dissertations

Following European settlement of the Lower Mississippi River Valley (LMRV), agricultural expansion and unsustainable, agriculturally related practices have caused groundwater depletion, soil erosion, and surface water contamination by eroded sediments and sediment-bound nutrients to become major environmental threats to the region. The objective of this study was to evaluate the effects of common landuses [i.e., native prairie, deciduous forest, coniferous forest, Conservation Reserve Program (CRP) grassland, and conventional-tillage (CT) and no-tillage (NT) agriculture] on surface water infiltration and aggregate-stability-related properties [i.e., water-stable macroaggregate (WSA) size distribution, total water-stable macroaggregate (TWSA) concentration, and mean weight diameter (MWD)]. The overall infiltration rate …


A Quantitative Assessment Of Trace Metals In Subsurface Soils And Groundwater In Agricultural Fields Of El Paso, Texas, Emmanuel Sosa Jan 2019

A Quantitative Assessment Of Trace Metals In Subsurface Soils And Groundwater In Agricultural Fields Of El Paso, Texas, Emmanuel Sosa

Open Access Theses & Dissertations

Intensive agricultural practices such as irrigation, application of pesticides and the use of fertilizers, as well as contamination from urban settings and industrial activities contribute to the input of trace metals onto soils and groundwater. Consequentially, biological uptake and accumulation concentrate these toxic metals in fruits, vegetables, and grains that will be used for human consumption. In southern New Mexico and western Texas, cropland is developed along the Rio Grande valley. These farmers are concerned about the quality of their irrigation water and soils in order to produce adequate crops and maintain healthy soils to maximize revenue. To evaluate loading …


Asian Jumping Worm (Megascolecidae) Impacts On Physical And Biological Characteristics Of Turfgrass Ecosystems, Ella L. Maddi Jan 2019

Asian Jumping Worm (Megascolecidae) Impacts On Physical And Biological Characteristics Of Turfgrass Ecosystems, Ella L. Maddi

Honors Theses

Asian Jumping worms (Megascolecid spp) were introduced to North America in the early 1900s and have been altering soils in forest ecosystems as they spread throughout the continent. The worms differ from other introduced earthworms in their ability to consume large densities of organic material and potentially alter nutrient cycling in the ecosystems that they invade (Greiner et al. 2012). This study examined if and how Asian jumping worms alter turfgrass systems by changing the biological or physical properties of soil. To do this we conducted a mesocosm experiment and observational field study. For the mesocosm study we inoculated boxes …


Seasonal Soil Carbon Fluxes In Transitioning Agricultural Soils In Central Washington State: Relations To Land-Use, Environmental Factors And Soil Carbon-Nitrogen Characteristics, Brandon Kautzman Jan 2019

Seasonal Soil Carbon Fluxes In Transitioning Agricultural Soils In Central Washington State: Relations To Land-Use, Environmental Factors And Soil Carbon-Nitrogen Characteristics, Brandon Kautzman

All Master's Theses

Changing agricultural land-use practices to increase soil carbon sequestration contributes to climate change mitigation and improved food security by moving CO2 from the atmosphere into soil as soil organic carbon (SOC). In 2016, a farm in Thorp, Washington, Spoon Full Farm, began converting land historically farmed using conventional methods of tillage and synthetic fertilizers to conservation farming methods with direct seeding and organic soil amendments with a goal of sequestering carbon in the soil. This project evaluates relationships of soil CO2 respiration and net ecological exchange (NEE) with land-use types, seasonal environmental factors (air temperature, relative humidity, soil …


Everyone Can Grow! Winter Programming Using An Indoor Horticulture Environmental Education Program To Benefit Military Veterans, Rachel Elam Jan 2019

Everyone Can Grow! Winter Programming Using An Indoor Horticulture Environmental Education Program To Benefit Military Veterans, Rachel Elam

WWU Graduate School Collection

Working with plants has numerous physical, mental health and well-being benefits for people, and military veteran farming programs have been started to provide these benefits. However, these programs lack activities outside of the Washington State growing season which is approximately May to October. Since these programs are largely meant as ways for veterans to engage in community and peer support, the gap over winter is unacceptable for the purposes of supporting mental health. This project produced a winter environmental education curriculum for military vets, titled Everyone can Grow! (ECG!), and is designed to provide peer support and psychological …


Column Tests Of Nitrate Breakthrough Behavior In Subsurface Sediments To Understand Transport In The Root-Zone, Rebecca Sally Haworth, Emma Rose Goodwin Jun 2018

Column Tests Of Nitrate Breakthrough Behavior In Subsurface Sediments To Understand Transport In The Root-Zone, Rebecca Sally Haworth, Emma Rose Goodwin

Natural Resources Management and Environmental Sciences

Nitrate has become an increasingly ubiquitous pollutant in surface and groundwater, posing a threat to hu- man health and ecosystems. Nitrogen is a necessary nutrient for plant growth and is limiting in many soils. As a result, farmers often add nitrogen to soil in a usable form such as nitrate, nitrite, or ammonia through the addition of fertilizer.


Exposure Of Kidney Bean (Phaseolus Vulgaris) Plants To Coated And Uncoated Zinc Oxide Nanomaterials Under Different Soil Conditions: Effects On Plant Growth And Seed Quality, Illya Aidee Medina Velo Jan 2018

Exposure Of Kidney Bean (Phaseolus Vulgaris) Plants To Coated And Uncoated Zinc Oxide Nanomaterials Under Different Soil Conditions: Effects On Plant Growth And Seed Quality, Illya Aidee Medina Velo

Open Access Theses & Dissertations

Soil exposure to engineered nanomaterials (NMs) occurs through the intentional use of nano-agrochemicals, incidental contamination from industrial-waste release, irrigation with wastewater and gray water, or amendment with NM-loaded sludge. Although there are several reports about the effects of NMs in terrestrial plants, there is still a lack of knowledge about the effects of NMs in crop plants and their edible portions.

Among the large list of produced NMs, it is estimated that 34,000 tons of ZnO NMs are produced yearly. Due to their growing applications in cosmetics and personal care products, there is a high possibility that the ZnO NMs …


Soil Science Lesson Plan For The Cal Poly Learn By Doing Lab, Kelsey Ormonde May 2017

Soil Science Lesson Plan For The Cal Poly Learn By Doing Lab, Kelsey Ormonde

Natural Resources Management and Environmental Sciences

To increase interest in soil science and other related sciences, educational materials need to be tailored to appeal to younger students. The purpose of this project was to create a soil science lesson plan that could be utilized by the Cal Poly Learn By Doing Lab. Information from several articles, textbooks, lesson plans, and websites was reviewed to create a soil science lesson plan for students in 5-8th grade. The lesson plan focused on the three sub-disciplines of soil science; physical, chemical, and biological. Activities were created to correspond to the three sub-disciplines. Alternate activities were created to allow …


Assessment And Characterization Of Microbial Communities In Salt Affected Soils On Galveston Island, Elaine Fowler May 2017

Assessment And Characterization Of Microbial Communities In Salt Affected Soils On Galveston Island, Elaine Fowler

Electronic Theses and Dissertations

After Hurricane Ike in 2008, Galveston Island was flooded with sea water that left the soil and groundwater of the island with elevated sodium concentrations. As part of a long-term study that aims to restore plant life to the island, various soil amelioration techniques are being evaluated. Samples from bedded and non- bedded plots treated with gypsum, mulch, or both were assessed for microbial populations. Samples collected in July and October 2016 were cultured on Tryptic Soy Agar (bacteria enumeration), Pseudomonas Agar, Actinomycete Agar, and Rose Bengal Agar (fungi enumeration). Bacteria populations ranged from 4.07 to 5.12 log CFU/gram and …


Effects Of Silvopasture Establishment On Aqueous And Gaseous Soil N Losses At The University Of New Hampshire Organic Dairy Research Farm, Kathryn Ann Slebodnik Jan 2017

Effects Of Silvopasture Establishment On Aqueous And Gaseous Soil N Losses At The University Of New Hampshire Organic Dairy Research Farm, Kathryn Ann Slebodnik

Honors Theses and Capstones

The expansion of local agriculture in the New England region is putting increased pressure on farmers to expand their arable land base. While clear-cutting is a traditional method of converting forested land to agriculture, it is known for having adverse ecological impacts. To minimize these impacts, farmers can create a silvopasture which incorporates a portion of the original forest canopy into pastures or crop fields. This study evaluates the impact of land-use changes for agriculture on soil nitrogen (N) retention. In particular, this study investigates the differences in soil N turnover, gaseous loss, and aqueous loss among an established forest, …


Cycling Of Gypsiferous White Sands Aerosols In The Shallow Critical Zone At White Mountain, New Mexico, Patrick Richard Rea Jan 2017

Cycling Of Gypsiferous White Sands Aerosols In The Shallow Critical Zone At White Mountain, New Mexico, Patrick Richard Rea

Open Access Theses & Dissertations

Dry deposition significantly affects evolution of the critical zone by nutrient supply and contributing to soil genesis. Dust influx and cycling in soils are difficult to quantify because dust sources can be chemically similar to local soils. White Sands, New Mexico, emits gypsum dust with a unique chemical and isotopic signature, providing an opportunity to investigate dust deposition and its movement in soils. This study evaluated the mobility of White Sands dust particles in the critical zone at White Mountain, New Mexico, a highland 100 km downwind. Four soil profiles were collected over limestone, igneous, mixed limestone and dolostone, and …


Quantifying Soil Greenhouse Gas Emissions And Soil Carbon Storage To Determine Best Management Practices In Agroecosystems, Tyler Goeschel Jan 2016

Quantifying Soil Greenhouse Gas Emissions And Soil Carbon Storage To Determine Best Management Practices In Agroecosystems, Tyler Goeschel

Graduate College Dissertations and Theses

Intensive agriculture, coupled with an increase in nitrogen fertilizer use, has contributed significantly to the elevation of atmospheric greenhouse gases (GHGs), including carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O). Rising GHG emissions usually mean a decrease in soil carbon. Currently, soil C is twice that of all standing crop biomass, making it an extremely important player in the C cycle. Fortunately, agricultural management practices have the potential to reduce agricultural GHG emissions whilst increasing soil C. Management practices that impact GHG emissions and soil C include various tillage practices, different N fertilization amounts and treatments (synthetic N, cattle …


Long-Term Impacts Of Conservation Management Practices On Soil Carbon Storage, Stability, And Utilization Under Cotton Production In West Tennessee, Candace Brooke Wilson Dec 2015

Long-Term Impacts Of Conservation Management Practices On Soil Carbon Storage, Stability, And Utilization Under Cotton Production In West Tennessee, Candace Brooke Wilson

Masters Theses

Biogeochemical cycling of soil carbon (C) is heavily influenced by conservation agricultural (CA) practices. This study examined SOC stability under three CA practices: reduced nitrogen (N) fertilizer application rate, cover cropping, and zero-tillage implemented for 31 years. Respiration rates measured from a 602-day incubation period were fitted to a double-pool first order exponential model of SOC decomposition. The active [respired] SOC pool showed distinct differences between applications of reduced (34N kg ha-1 [-1]) and high fertilization rates (101N kg ha-1) combined with tillage, and suggest that high fertilizer applications with conventional tillage allocated more C into a …


Response Of Soil Nitrification To The Veterinary Pharmaceuticals Monensin, Ivermectin And Zinc Bacitracin, Magda A. Konopka Dec 2014

Response Of Soil Nitrification To The Veterinary Pharmaceuticals Monensin, Ivermectin And Zinc Bacitracin, Magda A. Konopka

Electronic Thesis and Dissertation Repository

Pharmaceutical residues can reach agricultural land through amendment with animal or human waste. Since 2010, a series of replicated plots received annual applications of ivermectin, monensin and zinc bacitracin, either singly or in a mixture, at 0.1 mg/kg and 10 mg/kg concentrations. I collected soil samples before and after the fourth annual application of pharmaceuticals and assayed them for functional changes and amoA gene abundance, a gene needed for ammonia oxidation. In 2013, I exposed the soils to 100 mg/kg in a laboratory experiment which resulted in acceleration of nitrification. Under 10 mg/kg treatments in the field the abundance of …