Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons

Open Access. Powered by Scholars. Published by Universities.®

Agriculture

Environmental Indicators and Impact Assessment

Institution
Publication Year
Publication
Publication Type

Articles 1 - 30 of 43

Full-Text Articles in Physical Sciences and Mathematics

The Last Drought Frontier: Building A Drought Index For The State Of Alaska, Olivia Campbell May 2023

The Last Drought Frontier: Building A Drought Index For The State Of Alaska, Olivia Campbell

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

Drought is characterized by periods of below average precipitation. There are five major types of drought recognized in the literature: meteorological, hydrological, agricultural, socioeconomic, and ecological. A relatively new concept in the drought literature is “snow drought.” A key part of the definition of drought is that it is not always accompanied by extreme heat. This means drought can occur even in cold climates, cold seasons, and higher latitudes and altitudes, like Alaska. Drought is a natural part of climate variability, but Alaska’s climate is changing faster than any other state in the United States. Alaska is no stranger to …


Identifying Key Stream Restoration Variables In An Agriculturally Impaired Chesapeake Bay Watershed, Julia Portmann May 2022

Identifying Key Stream Restoration Variables In An Agriculturally Impaired Chesapeake Bay Watershed, Julia Portmann

Masters Theses, 2020-current

The Chesapeake Bay watershed spans several states, supports diverse ecosystems, and is crucial to local economies. However, agricultural practices in this region impair water quality. The Smith Creek watershed, within the Shenandoah Valley, was designated a showcase watershed in 2010 by the United States Department of Agriculture to demonstrate the efficacy of implementing restoration projects. We sampled fifteen farms ranging from unrestored to thirty-six years since restoration. At each site, we conducted a kick-net survey for macroinvertebrates, measured canopy cover, algal density, substrate size, and bank height and angle. We identified macroinvertebrates to family and calculated the Chesapeake Basin-wide Index …


Multi-Criteria Evaluation Model For Classifying Marginal Cropland In Nebraska Using Historical Crop Yield And Biophysical Characteristics, Andrew Laws May 2022

Multi-Criteria Evaluation Model For Classifying Marginal Cropland In Nebraska Using Historical Crop Yield And Biophysical Characteristics, Andrew Laws

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

Marginal cropland is suboptimal due to historically low and variable productivity and limiting biophysical characteristics. To support future agricultural management and policy decisions in Nebraska, U.S.A, it is important to understand where cropland is marginal for its two most economically important crops: corn (Zea mays) and soybean (Glycine max). As corn and soybean are frequently planted in a crop rotation, it is important to consider if there is a relationship with cropland marginality. Based on the current literature, there exists a need for a flexible yet robust methodology for identifying marginal land at different scales, which …


Los Impactos Del Cambio Climático En Las Comunidades Aymaras En Putre, El Valle De Azapa Y Arica, Lindsey Kaufman Apr 2022

Los Impactos Del Cambio Climático En Las Comunidades Aymaras En Putre, El Valle De Azapa Y Arica, Lindsey Kaufman

Independent Study Project (ISP) Collection

Research Question: How is climate change affecting Aymara communities in Putre, the valley of Azapa, and Putre?

Objectives: To understand the effects of climate on communities by 1) describing which environmental problems exist and their impact on agriculture and ranching, 2) understanding the patterns of migration away from the ancestral land, 3) exploring the connections to the social determinants of health that exist with these change, and 4) analyzing the significance of these changes in the agriculture for the communities’ traditions and connection to the land.

Background: Aymara communities have historically inhabited agricultural and ranching lands in …


Cover Crop Effects On Infiltration, Aggregate Stability, And Water Retention On Loessial And Alluvial Soils Of The Lower Mississippi River Valley, Shelby G. Lebeau Dec 2021

Cover Crop Effects On Infiltration, Aggregate Stability, And Water Retention On Loessial And Alluvial Soils Of The Lower Mississippi River Valley, Shelby G. Lebeau

Graduate Theses and Dissertations

Cover crops are a widely considered practice to improve soil health in the form of erosion control, organic matter additions, and improving water-holding capacity. Despite the well-documented benefits, little is known about the effect of cover crops on soils in the Lower Mississippi River Valley (LMRV), an area historically dominated by intensive cultivated agriculture, with soils prone to erosion, and unsustainable aquifer withdrawals for irrigation. The main objective of this study was to evaluate the effects of cover crops [with cover crops (CC) and without cover crops (NCC)] on near-surface soil physical/chemical- and infiltration-related properties, aggregate stability, and water retention. …


A Biological Assessment Of Water Quality In El Placer, Ecuador: The Effect Of Agriculture On Stream Health And The Quality Of Historical Versus Current Drinking Water Sources, Danielle Kleinberg Oct 2021

A Biological Assessment Of Water Quality In El Placer, Ecuador: The Effect Of Agriculture On Stream Health And The Quality Of Historical Versus Current Drinking Water Sources, Danielle Kleinberg

Independent Study Project (ISP) Collection

Although fresh water is one of Ecuador’s most abundant resources, high quality drinking water for its inhabitants is scarce (Wingfield et al., 2021). The most prevalent sources of water pollution in Ecuador are domestic waste, silver and gold mining, oil production, and agricultural chemicals (Buckalew et al., 1997). El Placer, a village located in Tungurahua, Ecuador, is highly dependent on agriculture as a source of income. The first objective of this study was to determine the effect of agriculture on the El Placer’s Tía Anita Stream through comparing the water quality at three sites with varying agricultural influence. The second …


Investigating The Impact Of Land Use On Avian Diversity And Abundance In Areas Surrounding Mabamba Swamp, Uganda, Sydney Marie Jones Oct 2021

Investigating The Impact Of Land Use On Avian Diversity And Abundance In Areas Surrounding Mabamba Swamp, Uganda, Sydney Marie Jones

Independent Study Project (ISP) Collection

The primary objective of this study was to investigate the impact of wetland-adjacent land use on avian species richness and abundance areas surrounding Mabamba Swamp, Uganda. Four types of land use were investigated: Eucalyptus plantations, wetland-edge agricultural fields, residential areas, and mature secondary forests. A total of 40-morning point counts were conducted for ten days in late November and late December of 2021. One-way ANOVA tests and Tukey’s HSD tests revealed significant differences in mean avian richness and abundance between all sites except residential areas and Nkima Forest. Additionally, Nkima Forest was found to contain the most number of specialist …


Solutions Human Centered Approach To Conservation, Illustration Department, History, Philosophy, + The Social Sciences Department Mar 2021

Solutions Human Centered Approach To Conservation, Illustration Department, History, Philosophy, + The Social Sciences Department

Illustration Course Work & Materials

"These essays were were written and illustrated by students at the Rhode Island school of Design in February, 2021. Their perspectives are entirely personal and reflect their efforts within a 5.5-week fused studio/seminar course that was centered on the Sixth Mass Extinction and how biodiversity is changing because of humans. Discovering that science communication is more than delivering just the facts, students were invited to research a topic of personal interest that is relevant to human impacts on biodiversity. Through analysis of data and other scientific information, each sought to synthesize their research and opinions on their topic through a …


Condition And Function Of Red River Valley Streams Receiving Nutrients From Human Activities In Manitoba, Canada, Kristin J. Painter Oct 2020

Condition And Function Of Red River Valley Streams Receiving Nutrients From Human Activities In Manitoba, Canada, Kristin J. Painter

Electronic Thesis and Dissertation Repository

Small tributary streams are conduits between the landscape and larger waterbodies and provide important ecosystem services including assimilation of nutrients from human activities which may be protective of downstream waterbodies. In the Red River Valley (RRV), Manitoba, numerous nutrient sources including agricultural runoff, livestock manure, and municipal wastewater effluent, have been attributed to the eutrophication of Lake Winnipeg and thus require targeted management to prevent loss of nutrients from land to lake. However, linkages between land-based nutrient-producing human activities in the RRV and the ecological status of the tributaries remain poorly understood. Furthermore, the proportional contribution of each source of …


Trend Of Thornthwaite's Aridity Index (Ai) At Atakpame (Togo), Komlan Koudahe Aug 2020

Trend Of Thornthwaite's Aridity Index (Ai) At Atakpame (Togo), Komlan Koudahe

English Language Institute

Drought can severely affect agricultural production potential, destroying the local economy and creating famine. Data were collected (1990 to 2014) from the Meteorological Department of Togo. Reference evapotranspiration (ETo) varied with two peaks obtained on March 28 (5.84mm) and on November 17 (4.87mm). There was water deficit in all years except 2005 and 2007. Also, there was non-significant increasing trend of aridity index (AI). Specific actions should target efficient water management in Atakpame.


What’S Going To Happen To My Pancakes? The Impacts Of Climate Change Upon Blueberries And Sugar Maple, Ashley Kayser May 2020

What’S Going To Happen To My Pancakes? The Impacts Of Climate Change Upon Blueberries And Sugar Maple, Ashley Kayser

Honors College

The United Nations believes that the foremost challenge of the future will be climate change. Because of human use of fossil fuels, greenhouse gases have been released into the atmosphere at unsustainable rates, which have resulted in an altered climate that will impact weather patterns around the globe. There have already been measurable shifts in precipitation and temperature in many regions; in the state of Maine the general trend has been toward higher temperatures and increased precipitation. This is resulting in impacts to agriculture throughout the state. Blueberries and sugar maple are two culturally and economically valuable crops which will …


Comprehensive And Agricultural Greenhouse Gas Emissions Inventories For Nebraska And The Midwest As Baselines For Climate Change Mitigation, Eric R. Holley Apr 2020

Comprehensive And Agricultural Greenhouse Gas Emissions Inventories For Nebraska And The Midwest As Baselines For Climate Change Mitigation, Eric R. Holley

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

Climate change is the paramount challenge of today for a sustainable future. Mitigation of greenhouse gas (GHG) emissions is necessary to reduce the associated risks and impacts on society. Using the EPA’s SIT and literature review, comprehensive GHG-emissions inventories were developed for the state of Nebraska over 25 years (1990-2015) and agricultural GHG emissions inventories were developed for the Midwest U.S for one year (2016). Nebraska’s net emissions increased from 56.2 million metric tons of carbon dioxide equivalent (MMtCO2e) in 1990 to 87.4 MMtCO2e in 2016. Agriculture was found to be the sector with the most …


Sustainability Of Industrialized Agriculture, Fall/Winter 2002, Issue 5 Sep 2019

Sustainability Of Industrialized Agriculture, Fall/Winter 2002, Issue 5

Sustain Magazine

No abstract provided.


Local Foods, Fall/Winter 2013, Issue 27 Sep 2019

Local Foods, Fall/Winter 2013, Issue 27

Sustain Magazine

No abstract provided.


A Framework For Tracing Social–Ecological Trajectories And Traps In Intensive Agricultural Landscapes, Daniel R. Uden, Craig R. Allen, Francisco Munoz-Arriola, Gengxin Ou, Nancy Shank Jan 2018

A Framework For Tracing Social–Ecological Trajectories And Traps In Intensive Agricultural Landscapes, Daniel R. Uden, Craig R. Allen, Francisco Munoz-Arriola, Gengxin Ou, Nancy Shank

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Charting trajectories toward sustainable agricultural development is an important goal at the food–energy–water–ecosystem services (FEWES) nexus of agricultural landscapes. Social–ecological adaptation and transformation are two broad strategies for adjusting and resetting the trajectories of productive FEWES nexuses toward sustainable futures. In some cases, financial incentives, technological innovations, and/or subsidies associated with the short-term optimization of a small number of resources create and strengthen unsustainable feedbacks between social and ecological entities at the FEWES nexus. These feedbacks form the basis of rigidity traps, which impede adaptation and transformation by locking FEWES nexuses into unsustainable trajectories characterized by control, stability, and efficiency, …


Understanding The Food Water Nexus: Characterizing The Impact Of Climatological Anomalies On Agrosystems, Patrick M. Wurster Jr. Jan 2018

Understanding The Food Water Nexus: Characterizing The Impact Of Climatological Anomalies On Agrosystems, Patrick M. Wurster Jr.

Graduate Student Theses, Dissertations, & Professional Papers

Climate variability at global and regional scales is escalating with increased atmospheric carbon and is expected to magnify the intensity and duration of meteorological extremes, especially droughts. From the many environmental stresses that diminish crop production (e.g., soil salinity, frost, soil erosion) drought is one of the most prevalent. This study focuses on the sensitivity of three key crops produced in the northwestern United States to climatological anomalies, while controlling for attribution using anomalies in price. The study differs from similar studies in that we focus on variability in production which captures both yield (tonnes/ha) and cropping area (ha), as …


Nutrient Contamination From Non-Point Sources: Dissolved Nitrate And Ammonium In Surface And Subsurface Waters At Eku Meadowbrook Farm, Madison County, Kentucky, Reid E. Buskirk, Hunter R. Evans, Walter S. Borowski, Jonathan M. Malzone Nov 2017

Nutrient Contamination From Non-Point Sources: Dissolved Nitrate And Ammonium In Surface And Subsurface Waters At Eku Meadowbrook Farm, Madison County, Kentucky, Reid E. Buskirk, Hunter R. Evans, Walter S. Borowski, Jonathan M. Malzone

EKU Faculty and Staff Scholarship

Agricultural activities often contaminate watersheds with excess nutrients leading to poor water quality and eutrophication. We assayed dissolved nutrient levels in surface and subsurface waters of Eastern Kentucky University’s Meadowbrook Farm in order to assess levels of dissolved nutrients leaving its farmland and draining into the Muddy Creek watershed. The Farm raises both crops and livestock so that nutrient sources include fertilizer and manure. We sampled springs, runoff, and subsurface pipe drainage as well as Muddy Creek on six days from May to August 2016 under a variety of weather conditions. Using established, standard colorimetric methods, we measured nitrate (NO …


Nutrient Contamination From Non-Point Sources: Dissolved Phosphate In Surface And Subsurface Waters At Eku Meadowbrook Farm, Madison County, Kentucky, Hunter R. Evans, Reid E. Buskirk, Walter S. Borowski, Jonathan M. Malzone Nov 2017

Nutrient Contamination From Non-Point Sources: Dissolved Phosphate In Surface And Subsurface Waters At Eku Meadowbrook Farm, Madison County, Kentucky, Hunter R. Evans, Reid E. Buskirk, Walter S. Borowski, Jonathan M. Malzone

EKU Faculty and Staff Scholarship

Farms are non-point sources for nutrient contaminants that drain into watersheds and contribute to eutrophication and other environmental problems. Eastern Kentucky University’s Meadowbrook Farm raises both crops and livestock, causing dissolved phosphorus in the form of orthophosphate (PO43-) from fertilizer and animal manure to enter surface and subsurface waters, eventually flowing into Muddy Creek, a tributary of the Kentucky River.

We sampled surface water, springs, and water from French drains that emanate from the farm, and also sampled Muddy Creek waters from May through August 2016. Typically, 1 to 2 days after sampling, we colorimetrically measured dissolved …


Determining Effects Of Heat Stress On Illinois Soybeans, Ava Alford, Charles Burroughs, Lisa Ainsworth Jul 2017

Determining Effects Of Heat Stress On Illinois Soybeans, Ava Alford, Charles Burroughs, Lisa Ainsworth

PRECS student projects

Rising global temperatures affect our food supply. Heat stress could negatively affect photosynthesis, plant development, and flower and pod production. The research summarized in this poster aims to better understand which physiological processes in soybeans are negatively affected by heat stress in order to identify targets for future soybean production. Using infrared heat arrays, two different cultivars of Illinois soybeans are continually heated. Throughout the experiment, data is collected on photosynthesis, leaf area index, and overall productivity of the plant. At the end of the growing season, all of the soybean plants will be harvested and their biomass will be …


Financial Assessment Of Agricultural Lands At Risk To Coastal Salt Marsh Migration In Relation To Climate Change Induced Sea Level Rise In Dorchester County, Maryland, Jewell Porter May 2017

Financial Assessment Of Agricultural Lands At Risk To Coastal Salt Marsh Migration In Relation To Climate Change Induced Sea Level Rise In Dorchester County, Maryland, Jewell Porter

International Development, Community and Environment (IDCE)

The increasing rate and effects of sea level rise is a major environmental concern in the Chesapeake Bay. This paper evaluates the impacts of rising sea level on coastal salt marshes and the surrounding agricultural lands at risk in Dorchester County, Maryland to build off existing environmental monitoring work performed by NOAA’s Sentinel Site Program. The results of the spatial analysis were used to estimate monetary benefits to incentivize farmers to protect these marshes by making their land available for marsh migration to occur. Looking at three scenarios of sea level rise and marsh migration, grain crops (corn, soybeans, and …


Nutrient Contamination From Non-Point Sources: Dissolved Phosphate In Surface And Subsurface Waters At Eku Meadowbrook Farm, Madison County, Kentucky, Hunter R. Evans, Reid E. Buskirk, Walter S. Borowski, Jonathan M. Malzone Mar 2017

Nutrient Contamination From Non-Point Sources: Dissolved Phosphate In Surface And Subsurface Waters At Eku Meadowbrook Farm, Madison County, Kentucky, Hunter R. Evans, Reid E. Buskirk, Walter S. Borowski, Jonathan M. Malzone

EKU Faculty and Staff Scholarship

Farms are non-point sources for nutrient contaminants that drain into watersheds and contribute to eutrophication and other environmental problems. Eastern Kentucky University’s Meadowbrook Farm raises both crops and livestock, causing dissolved phosphorus in the form of orthophosphate (PO43-) from fertilizer and animal manure to enter surface and subsurface waters, eventually flowing into Muddy Creek, a tributary of the Kentucky River.

We sampled surface water, springs, and water from French drains that emanate from the farm, and also sampled Muddy Creek waters from May through August 2016. Typically, 1 to 2 days after sampling, we colorimetrically measured dissolved …


Agricultural Trade Publications And The 2012 Midwestern U.S. Drought: A Missed Opportunity For Climate Risk Communication, Sarah P. Church, Tonya Haigh, Melissa Widhalm, Silvestre Garcia De Jalon, Nicholas Babin, J. Stuart Carlton, Michael Dunn, Katie Fagan, Cody L. Knutson, Linda Stalker Prokopy Jan 2017

Agricultural Trade Publications And The 2012 Midwestern U.S. Drought: A Missed Opportunity For Climate Risk Communication, Sarah P. Church, Tonya Haigh, Melissa Widhalm, Silvestre Garcia De Jalon, Nicholas Babin, J. Stuart Carlton, Michael Dunn, Katie Fagan, Cody L. Knutson, Linda Stalker Prokopy

Drought Mitigation Center: Faculty Publications

The Midwestern United States experienced a devastating drought in 2012, leading to reduced corn and soybean yields and increased instances of pests and disease. Climate change induced weather variability and extremes are expected to increase in the future, and have and will continue to impact the agricultural sector. This study investigated how agricultural trade publications portrayed the 2012 U.S. Midwestern drought, whether climate change was associated with drought, and whether these publications laid out transformative adaptation measures farmers could undertake in order to increase their adaptive capacity for future climate uncertainty. We performed a content analysis of 1000 media reports …


Dispersion Of Ammonia From Concentrated Animal Feeding Operations, Austin D. Wardall Oct 2016

Dispersion Of Ammonia From Concentrated Animal Feeding Operations, Austin D. Wardall

Masters Theses & Specialist Projects

The purpose of this research is to investigate the dispersion of ammonia (NH3) from three Concentrated Animal Feeding Operations (CAFOs) in western Kentucky, as well as to investigate the Weather Research and Forecasting – Chemistry (WRF-Chem) model’s sensitivity response to initial NH3 concentrations under both wet conditions (significant precipitation) and dry conditions (no precipitation). As expected, pollutant concentrations generally were significantly higher near their points of origin and generally declined away from the sources. Contrary to expectations, ammonia tended to rise through the planetary boundary layer (PBL) regardless of atmospheric conditions. Results showed modeled NH3 pollution levels at the surface …


The Measure Of Nematode Diversity In Response To Varying Management Practices And Features In Restored And Remnant Prairie Ecosystems, Heaven A. Hulshizer Apr 2016

The Measure Of Nematode Diversity In Response To Varying Management Practices And Features In Restored And Remnant Prairie Ecosystems, Heaven A. Hulshizer

UCARE Research Products

"Tallgrass prairies are the most endangered ecosystem in North America” (Helen et al 2013). “Surveys suggest that since European settlement, declines in area of native prairie range as high as 99.9%”(Sampson, Fred and Fritz Knopf 1994). Prairie ecosystem services are abundant and range from mitigating floods to promoting biodiversity. (USDA Forest Service).Given these benefits, restoring prairies and maintaining native areas should be an important conservation priority. Nematodes, the most abundant animal species on earth, have been used as bio-indicators of soil quality (Neher; Todd). To better understand the dynamics of nematode diversity in native and restored prairies we examines whether …


Assessing The Evolution Of Soil Moisture And Vegetation Conditions During The 2012 United States Flash Drought, Jason A. Otkin, Martha C. Anderson, Christopher R. Hain, Mark D. Svoboda, David K. Johnson, Richard Mueller, Tsegaye Tadesse, Brian D. Wardlow, Jesslyn Brown Jan 2016

Assessing The Evolution Of Soil Moisture And Vegetation Conditions During The 2012 United States Flash Drought, Jason A. Otkin, Martha C. Anderson, Christopher R. Hain, Mark D. Svoboda, David K. Johnson, Richard Mueller, Tsegaye Tadesse, Brian D. Wardlow, Jesslyn Brown

Drought Mitigation Center: Faculty Publications

This study examines the evolution of several model-based and satellite-derived drought metrics sensitive to soil moisture and vegetation conditions during the extreme flash drought event that impacted major agricultural areas across the central U.S. during 2012. Standardized anomalies from the remote sensing based Evaporative Stress Index (ESI) and Vegetation Drought Response Index (VegDRI) and soil moisture anomalies from the North American Land Data Assimilation System (NLDAS) are compared to the United States Drought Monitor (USDM), surface meteorological conditions, and crop and soil moisture data compiled by the National Agricultural Statistics Service (NASS).

Overall, the results show that rapid decreases in …


Towards Measuring Interventions In Rainfed Areas, Hippu Salk Kristle Nathan, Rajendra, Srijit Mishra Jan 2015

Towards Measuring Interventions In Rainfed Areas, Hippu Salk Kristle Nathan, Rajendra, Srijit Mishra

Srijit Mishra

This paper underlines the process through which we have arrived at the indicators for various thematic nodes to measure and evaluate interventions or comprehensive pilots in rainfed areas. We conceptualize a simple four stage process, i.e., ‘objective or goal formulation’, 'means finding', 'targets settings' and 'indicator identification', which we refer to as OMTI (Objective-Means-Target-Indicators) framework. In indicator literature, this kind of framework can be categorized under "thematic framework" or "goal oriented framework". The operationalization of OMTI framework highlights its nuances and brings forth its limitations. In order to overcome some of these limitations, we validate the OMTI framework using the …


A Historical Perspective On Nebraska’S Variable And Changing Climate, Martha Shulski, William Baule, Crystal J. Stiles, Natalie A. Umphlett Jan 2015

A Historical Perspective On Nebraska’S Variable And Changing Climate, Martha Shulski, William Baule, Crystal J. Stiles, Natalie A. Umphlett

HPRCC Personnel Publications

Nebraska is situated at the intersection of the northern and southern Great Plains, exhibiting a dramatic longitudinal gradient for precipitation and humidity, and benefiting from groundwater resources. The continental climate is highly variable temporally both for temperature and precipitation. Our assessment of long-term meteorological observations shows that over the last century the annual average temperature in Nebraska has warmed approximately 0.6°C, which is similar to the increase in the global average temperature over the same time period. Furthermore, we found minimum temperatures have warmed more than maximum temperatures, and winter and spring show the strongest warming. We found no significant …


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 …


Determining The Association Between The Structure Of Stream Benthic Macroinvertebrate Communities And Agricultural Best Management Practices, Roger Holmes Sep 2014

Determining The Association Between The Structure Of Stream Benthic Macroinvertebrate Communities And Agricultural Best Management Practices, Roger Holmes

Electronic Thesis and Dissertation Repository

Farmers have been encouraged to adopt more sustainable farming practices (BMPs) that mitigate adverse agricultural effects on the natural environment. However, the ability of BMPs to protect or restore riverine systems continues to be questioned due to limited evidence directly linking BMP use with improved ecological conditions. The exclusion of hydrological pathways in previous field studies may explain why a direct link has not yet been established. The goal of this study was to assess the association between benthic macroinvertebrate community structure and the number and location of agricultural BMPs. Macroinvertebrates and water chemistry were sampled in 30 headwater catchments …


Soil Organic Carbon Dynamics In Agriculture: Model Development And Application From Daily To Decadal Timescales, Matthew P. Pelton May 2013

Soil Organic Carbon Dynamics In Agriculture: Model Development And Application From Daily To Decadal Timescales, Matthew P. Pelton

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

Soil carbon (C) is the largest terrestrial C pool globally, containing more C than the atmosphere and biosphere. Soil organic carbon (SOC) is a source and sink of CO2 emissions to and from the atmosphere, thus influencing future climate change. Understanding SOC dynamics is also important for maintaining C stocks to sustain and improve crop yields. An existing model to estimate changes in SOC due to respiration was modified to operate in three computational platforms: MS Excel, MS Excel with Visual Basic for Applications, and supercomputing. This model was validated against CO2 flux data from a 9-year field …