Agronomy and Crop Sciences Commons^™

Plas 439: Organic Farming And Food Systems Faculty-Led Inquiry Into Reflective Scholarly Teaching Benchmark Portfolio, Christian Stephenson

UNL Faculty Course Portfolios

Organic Farming and Food Systems is a senior and graduate level course for students in the Department of Agronomy and Horticulture. This course was previously offered but has been significantly modified as I have taken on responsibility for the course. Goals for the course include student comprehension of the methods of organic and regenerative farming and the impacts of those methods on economic, environmental, and social sustainability. An additional goal is to build student competency in the evaluation of primary, secondary, and tertiary information resources and critical thinking surrounding issues in food production. Assessment for the course was through diverse …

Predicting The Potential Distribution Of Pseudococcus Longispinus (Targioni-Tozzetti) (Hemiptera: Pseudococcidae) In South Korea Using A Climex Model, Su Bin Kim, Soo-Jung Suh

Insecta Mundi

Pseudococcus longispinus (Targioni-Tozzetti) (Hemiptera: Pseudococcidae) is a widely-distributed pest that feeds on many economically important hosts, particularly tropical fruits and ornamentals. The potential distribution of this mealybug pest in South Korea remains a primary concern because of its high incidence of interceptions screened during inspection. Hence, this species prompted a modelling effort to assess its potential risk of introduction. Potential risk maps were developed for this pest with a CLIMEX model based on occurrence records under environmental data. The potential distribution of these pests in South Korea in the 2020s, 2050s and 2090s was projected based on the RCP 8.5 …

Will Saf Turbocharge The Corn Ethanol Market?, Richard Perrin, Lilyan Fulginiti, Felipe Miranda De Souza Almeida

Cornhusker Economics

The long-run outlook for the corn ethanol industry is questionable, due to a transition to electric and hybrid vehicles. One source of hope for the long run is the potential demand for producing Sustainable Aviation Fuel (SAF). SAF is a key component in the United States Aviation Climate Action Plan, a path to net-zero greenhouse gas (GHG) emissions in the aviation industry by 2050. Demand for ethanol for SAF offers hope to the ethanol industry, but it depends a great deal on policy decisions that are being made now. Here we sketch out this story.

Based on the information available …

Pollinator Communities And Their Ecosystem Services At Conservation Grasslands And Adjacent Croplands, Araceli Gomez Villegas

Department of Entomology: Dissertations, Theses, and Student Research

Pollinators are intrinsically linked to the success of unmanaged and managed ecosystems by providing pollination services that aid in the reproduction of wildflowers and many crops. Land use change, habitat loss, fragmentation, and related landscape-level phenomena (for example, increased pesticide exposure) threaten pollinators and have been associated with population declines. In the Midwestern region of the United States, land conversion of native prairies and grasslands to row-crop agriculture has been one of the largest contributors to pollinator habitat loss. Conservation programs, such as the Conservation Reserve Program, have worked towards removing environmentally sensitive lands from agriculture production and enrolling them …

Field Research Report: Results From The Enreec Vri Field For The 2021, 2022, And 2023 Crop Seasons, Derek M. Heeren, Ali T. Mohammed, Eric Wilkening, Christopher M. U. Neale, Alan L. Boldt, Ankit Chandra, Precious Nneka Amori, Ivo Z. Goncalves, Yeyin Shi, Guillermo R. Balboa

Department of Biological Systems Engineering: Conference Presentations and White Papers

Long-term irrigation management research has been conducted from 2014 to 2023 for corn and soybean at the Eastern Nebraska Research, Extension, and Education Center (ENREEC) Variable Rate Irrigation (VRI) Field located in subhumid east-central Nebraska (in the Lower Platte North Natural Resources District). The objective of this report was to present the overall results from the VRI Field for 2021 to 2023. Across the three growing seasons, there were the following irrigation treatments: Best Management Practice (BMP), 50% BMP, 125% BMP, rainfed, Spatial ET Modeling Interface (SETMI), SDD1, SDD2, machine-learning-based Cyber-Physical System (CPS), a student team recommended rate, and industry …

Perennializing Marginal Croplands: Going Back To The Future To Mitigate Climate Change With Resilient Biobased Feedstocks, Salvador Ramirez Ii, Marty R. Schmer, Virginia L. Jin, Robert B. Mitchell, Catherine E. Stewart, Jay Parsons, Daren D. Redfearn, John J. Quinn, Gary E. Varvel, Kenneth P. Vogel, Ronald F. Follett

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Managing annual row crops on marginally productive croplands can be environmentally unsustainable and result in variable economic returns. Incorporating perennial bioenergy feedstocks into marginally productive cropland can engender ecosystem services and enhance climate resiliency while also diversifying farm incomes. We use one of the oldest bioenergy-specific field experiments in North America to evaluate economically and environmentally sustainable management practices for growing perennial grasses on marginal cropland. This long-term field trial called 9804 was established in 1998 in eastern Nebraska and compared the productivity and sustainability of corn (Zea mays L.)—both corn grain and corn stover—and switchgrass (Panicum virgatum …

Life Cycle Greenhouse Gas Emissions In Maize No-Till Agroecosystems In Southern Brazil Based On A Long-Term Experiment, Guilherme Rosa Da Silva, Adam J. Liska, Cimelio Bayer

Department of Biological Systems Engineering: Papers and Publications

Brazilian agriculture is constantly questioned concerning its environmental impacts, particularly greenhouse gas (GHG) emissions. This research study used data from a 34-year field experiment to estimate the life cycle GHG emissions intensity of maize production for grain in farming systems under no-tillage (NT) and conventional tillage (CT) combined with Gramineae (oat) and legume (vetch) cover crops in southern Brazil. We applied the Feedstock Carbon Intensity Calculator for modeling the “field-to-farm gate” emissions with measured annual soil N₂O and CH₄ emissions data. For net CO₂ emissions, increases in soil organic C (SOC) were applied as a proxy, …

Assessing The Morphological And Physiological Traits Of Smooth Brome Pastures Under Long Term Grazing And Nutrient Enrichment In Eastern Nebraska, Hassan Shehab

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

Climate change together with the increase in demands for food, feed, fuel, and fiber are becoming a threat to sustainability and resilience of agriculture and pasture lands. Bromus inermis (smooth bromegrass) dominates pastures for cattle grazing in Eastern Nebraska, US, where it is planted in monocultures, and is considered high quality forage because of its palatability and high nutritional value for cattle, especially under intensive management practices. Sustainable management of these pastures is key to long-term resilience. This study aims to assess the performance of smooth bromegrass pastures to the combined effects of long-term management practices (since 2005) of fertilization …

Portugal To New Mexico: Investigating The Applicability Of Syntropic Agriculture To A Semi-Arid Continental Climate, Arielle Nathan

Independent Study Project (ISP) Collection

Conventional industrial agriculture has numerous detrimental effects on the environment including high carbon emissions, pollution and overconsumption of water, soil degradation, and reduction of biodiversity (FAO, 2018). Large-scale alternatives are needed to combat these negative consequences and provide climate solutions. Syntropic Agriculture is a promising farming alternative especially in arid systems subject to degraded soils and desertification. New Mexico is a semi-arid continental climate in a prolonged period of drought and predicted to experience worsening agricultural conditions due to desertification, wildfire intensification, and exacerbated water scarcity. In an area with similar agricultural challenges, a project in Mértola, Portugal (Terra Sintrópica) …

The Truth Behind Avocado Expansion In The Algarve: A Synthesis Of Public, Environmental Associations, And Government Perspectives And Response, Mandy Ausman

Independent Study Project (ISP) Collection

Avocado expansion has exponentially increased in the Algarve region of southern Portugal in recent years. The surge in expansion has provoked contention and discrepancy in the media regarding how and if avocado production can persist in the water-scarce region due to worsening drought conditions related to climate change coupled with the fruit’s significant water footprint. This paper aims to synthesize the arguments and response of the public, environmental associations, and government agencies to the expansion of avocado production in the water- scarce region of the Algarve, highlight the region’s current challenges of avocado expansion and water management regulation, and analyze …

Assessing The Performance Of Agricultural Systems In The Inland And Coastal Regions Of Northern Portugal Using Indicators: Establishing The Foundation Towards Better Agricultural Practices, Genevieve Gehlken

Independent Study Project (ISP) Collection

This study conducts a comprehensive evaluation of agricultural systems in the distinct coastal and inland regions of Northern Portugal. Employing key indicators, including soil erosion, nitrogen surplus, irrigation practices, Agricultural Gross Domestic Product (GDP), and crop yield, the analysis reveals statistically significant disparities and unique challenges in each region. The coastal areas, marked by higher agricultural GDP, exhibit distinct economic dependencies on agriculture, while the inland regions face challenges related to water scarcity, soil erosion, and rural isolation. The looming threat of climate change adds complexity to these dynamics, further highlighting the need for region-specific, sustainable agricultural practices. In the …

Deficit Irrigation Management For Irrigated Corn In Nebraska: Economically Viable?, Lia Nogueira, Cory Walters, Emily O'Donnell, Wesley Peterson, Suat Irmak

Cornhusker Economics

In this study we determine the economic value of deficit irrigation management using both technological and methodological advancements. The use of soil moisture probes represents the technological improvement. We provide improvements in the methodology as follows. Regarding data, we employ a field-size study, instead of plots, where the irrigation decision is determined by the moisture level in the soil measured through a soil moisture probe. Regarding the understanding of the yield response to water, although we examine the commonly used quadratic function, we improve upon this specification by also examining an alternative response function, the linear response stochastic plateau. Our …

Carbon Farming: A Preliminary Economic Analysis Of Carbon Credits For No-Till And Cover Crops, Drew Havens, Richard K. Perrin, Lilyan E. Fulginiti

Cornhusker Economics

Summary Based on experimental data about the amount of carbon sequestered and estimated implementation costs, our preliminary results show that the average cost of sequestering carbon via no-till (about $22 per ton of CO₂e) appears to be much lower than the $51 per ton social value of sequestering that ton. In contrast, our preliminary results show that the average costs of sequestration via adoption of cover crops is much higher, about $60 per ton. Depending on how accurate soil carbon models are in predicting sequestration on individual fields to qualify them for enrollment, reimbursement costs for planting cover …

Teaching Agroecology: Preparing Students For Navigating Uncharted Territory, Charles A. Francis, Steve Gliessman

Department of Agronomy and Horticulture: Faculty Publications

Agroecologists understand that farming and food systems are more complex than the aggregation of their components. This realization drives our choices of learning strategies and activities that will prepare students for complexity and uncertainty. Our quest for a just, sustainable, and nutritious food system adequate to equitably serve everyone on the planet today and into the future is an enormous challenge. An undertaking of this magnitude will be met only with major adjustments informed by thoughtful teaching and practicing problem solving skills through a new educational lens. The principles of agroecology help us focus this lens on the wicked problems …

An Analysis Of Decolonization Efforts In Urban Agriculture: A Pathway To Indigenous Food Sovereignty And Cultural Revitalization, Sarah Fisher

Environment and Sustainability Summer Fellows

My research focuses on applications of urban agriculture, relationships between Indigenous peoples and community-based agriculture projects, and decolonizing food systems. I provide insight on colonialist tendencies, or ways in which the marginalization of Indigenous peoples is deeply entrenched within government, educational, and other leadership settings, as a way to evaluate and restructure urban agriculture projects to serve, represent and heal Native communities. Conventional urban agriculture has many known benefits, including its capacity for food production; however, the extent to which Indigenous communities participate in and benefit from urban agriculture has not been widely studied. Ongoing exclusion of Indigenous peoples from …

Whole Farm Net Zero: Approaches To Quantification Of Climate Regulation Ecosystem Services At The Whole Farm Scale. Vermont Payment For Ecosystem Services Technical Report #7, Christopher Bonasia, Lindsey Ruhl, Benjamin Timothy Dube, Alissa C. White, Heather M. Darby

UVM Extension Faculty Publications

In this report, approaches to the quantification of climate mitigation ecosystem services at the whole farm scale are reviewed and summarized for easy comparison. Eight quantification tools, and three case studies demonstrating possible tool applications, are summarized to fulfill the requirements of the Technical Services Contract—Task 7. Information from a combination of literature review and expert interviews served to document the inputs, outputs, strengths, weaknesses, opportunities, and threats for each quantification tool. This research was conducted in service to the Vermont Soil Health and Payment for Ecosystem Services (PES) Working Group (VT PES working group). It is our hope that …

Valuation Of Soil Health Ecosystem Services. Vermont Payment For Ecosystem Services Technical Research Report #5, Benjamin Timothy Dube, Alissa C. White, Taylor H. Ricketts, Heather M. Darby

UVM Extension Faculty Publications

In this report, we present estimates for ecosystem services from soil health using two approaches for four different services. One approach generates estimates based on soil-health practices, and the other approach is based on improvements in soil-health indicators. For soil- health practices, such as adopting best-management practices on annual corn, we utilize a set of off-the shelf empirical models widely used to estimate ecological functions on farm landscapes. For soil-health indicators, we make estimates by linking these tools with soil data and statistical models describing how soil-health parameters influence the interaction of soils with water and their environment. We provide …

Results Of The 2022 Vermont Farmer Conservation & Payment For Ecosystem Services Survey. Vermont Payment For Ecosystem Services Technical Research Report #3a, Alissa C. White

Reports and Policy Briefs

This survey was commissioned by the Vermont Soil Health and Payment for Ecosystem Services Working Group (VT PES Working Group) to gather farmer input on the development of payment for ecosystem services (PES) in Vermont for agriculture. In particular, the survey was intended to help set appropriate levels of compensation for participation in a soil health PES program, although additional information was gathered in the survey to inform the development of a new incentive program. The VT PES Working Group has explored the potential for a performance-based soil health PES program that would compensate farmers on the basis of environmental …

Field Scale Soil Health Scenarios. Vermont Payment For Ecosystem Services Technical Report #2, Alissa C. White, Heather M. Darby, Lindsey C. Ruhl, Bryony Sands, Sara Ziegler,, Juan P. Alvez, Sarah Brickman

UVM Extension Faculty Publications

This report illustrates how changes in management on Vermont farms can influence soil health metrics at the field scale. We’ve used regionally relevant science-based scenarios to demonstrate how selected soil health metrics that are associated with ecosystem services could change on farms in response to management practices at the field scale. These field scale management scenarios demonstrate that many practices in use by farmers in Vermont can have positive impacts on the soil health indicators of interest to the Vermont Soil Health & Payment for Ecosystem Services Working Group. The scenarios document potential for tradeoffs among soil health properties. Specifically, …

Soil Carbon Storage And Sequestration In Vermont Agriculture, Alissa C. White, Heather M. Darby, Donald Ross

UVM Extension Faculty Publications

In 2021, The State of Soil Health (SOSH) project measured indicators of soil health on 221 farm fields across the state of Vermont through a collaborative effort among many organizations. Soil carbon stocks to 30 cm depth were assessed on 191 of those fields. In this brief we share a summary of this new soil carbon stock data alongside data from a national assessment of soil carbon stocks performed by the NRCS from 2010 and highlight its relevance to current policy conversations within the state of Vermont.

Key Ideas

• The protection of existing soil carbon stocks and support for increased …

Effects Of Foliar Application Of Zno Nanoparticles On Lentil Production, Stress Level And Nutritional Seed Quality Under Field Conditions, Marek Kolenčík, Dávid Ernst, Matej Komár, Martin Urík, Martin Šebesta, Ľuba Ďurišová, Marek Bujdoš, Ivan Černý, Juraj Chlpík, Martin Juriga, Ramakanth Illa, Yu Qian, Huan Feng, Gabriela Kratošová, Karla Čech Barabaszová, Ladislav Ducsay, Elena Aydın

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Nanotechnology offers new opportunities for the development of novel materials and strategies that improve technology and industry. This applies especially to agriculture, and our previous field studies have indicated that zinc oxide nanoparticles provide promising nano-fertilizer dispersion in sustainable agriculture. However, little is known about the precise ZnO-NP effects on legumes. Herein, 1 mg·L⁻¹ ZnO-NP spray was dispersed on lentil plants to establish the direct NP effects on lentil production, seed nutritional quality, and stress response under field conditions. Although ZnO-NP exposure positively affected yield, thousand-seed weight and the number of pods per plant, there was no statistically significant …

Regenerating Agroecosystems By Overcoming Human Exceptionalism In Designing For Increased Equity Of Benefits From Ecoservices, Ali Loker, Charles A. Francis

Department of Agronomy and Horticulture: Faculty Publications

Our commentary explores three critical issues related to ecosystem services. First is how ecoservices are currently designed and implemented primarily for human benefit without concern for how these impact other species. We conclude that awareness of this imbalance is the first step toward meaningful change. Second we observe that human exceptionalism guides most decisions, and ask whether we can overcome this mind-set to embrace ecoregeneration and design of resilient and mutually beneficial agroecosystems. Our attitude toward the challenge and moving toward greater humility about human roles that guide management decisions in the ecosystem is a requisite for change. Third we …

Gaia Contributions To Agroecology By James Lovelock (1919-2022), Steve Gliessman, Charles A. Francis

Department of Agronomy and Horticulture: Faculty Publications

In writing about the history of agroecology we too often ignore the valuable contributions of British scientist James Lovelock who recently died on his 103rd birthday. A prolific inventor and influential theorist, Lovelock is best known for the Gaia hypothesis first proposed during his innovative work in the 1960s with the United States National Aeronautics and Space Administration. He suggested that ‘the biosphere has a regulatory effect on the Earth’s environment that acts to sustain life’ as written in Gaia: A New Look at Life on Earth (Lovelock 1979). Lovelock further proposed that humans have strongly impacted the planet’s capacity …

American Burying Beetle, Plant Richness, And Soil Property Responses To Collapse Of Juniperus Virginiana Woodlands With Fire, Alison Ludwig

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Grasslands are declining in the Great Plains due to land use changes, woody plant encroachment, and loss of historic fire cycles. Prescribed burn associations have utilized prescribed fire to collapse invading woodlands and allow the restoration of grasslands. This fire is considered “extreme” because it is capable of changing the structure and function of an ecosystem. Our study site is the Loess Canyons Experimental Landscape, a long-term, ecoregion-scale experiment to apply prescribed fire across the region to restore grasslands. The Nebraska Natural Legacy Project established the Loess Canyons ecoregion as a Biologically-Unique Landscape in 2005 with the state’s wildlife action …

Evaluation Of Harvesting Time For Industrial Hemp (Cannabis Sativa L,) Pilot Project Varieties Grown In South Florida, Jordan W. Prats

FIU Electronic Theses and Dissertations

A field study was conducted to observe the natural development of cannabinoids in three daylength sensitive industrial hemp varieties Bubba Kush (BK), Emerald Flower (EF), and Golden Sunset (GS). Plants were configured in a randomized block design with 3 replications. Once 50% of the plants within a variety reached reproductive growth, plants were sampled weekly until senescence and analyzed through a HPLC-UV/DAD. The results from the study indicate that all three varieties of industrial hemp tested in field study reached reproductive growth within the first week of transplanting. This is due to a 12-hour day-length at the time and the …

Production And Characterization Of Twelve Different Biochars And Evaluating Their Effects On Soil Health And Plant Growth, Shagufta Gaffar

FIU Electronic Theses and Dissertations

Biochar has been a topic of growing interest in the scientific community. It is a product derived from carbon rich organic materials through the process of pyrolysis. It has received wide attention as a means to improve soil fertility and crop productivity, absorb pollutants in soil, and sequester carbon to mitigate climate change. Recent research on biochar explores its impacts on the environment with particular focus on use as a soil amendment in agriculture. Biochar produced from different biomass and under different production process effects the environmental and agronomic impacts of its application in different ways. This means biochar can …

Hu Aquaponics Monitoring And Control System : European Annual Edunet Conference 2020, Rachel L. Fogle, Glenn P. Williams, Josh R. Krug

Presidential Research Grants

The functional purpose of the HU Aquaponics Monitoring and Control System Project is to develop an environmental and plant monitoring and control system for the HU Aquaponics Lab, located in the Student Union. The project involves the design and implementation of technology that will regularly take measurements from the environment (e.g., air temperature, water temperature, pH, dissolved oxygen, etc). PLCnext Technology will systematically collect, store, and web-publish the measurement data for HU researchers and the public to use for scientific research.

Projected Surface Water For Fruit And Vegetable Irrigation Under A Changing Climate In The Us, Marty Matlock, Greg Thoma, Kieu Ngoc Le, Eric Cummings, Zach Morgan, Andrew Shaw

Water Systems

Increasing greenhouse gas concentrations in the atmosphere, resulting in climate impacts, are raising concerns over the hydrologic cycle and its effects upon agricultural productivity. If rainfall patterns change, meeting an increased demand for fruits and vegetables will pose a challenge for domestic production regions in the United States (U.S.). Information on potential water supply scarcity in the current production regions provides decision makers with critical information for risk mitigation for future production. We used a hydrologic balance-based model of historic and future water availability to evaluate risk of available irrigation water to support major fruit and vegetable production the US. …

Impact Of Agricultural Land Use On Stream Nitrate, Phosphorus, And Sediment Concentrations At The Watershed And Field Scale, Brittany A. Kirsch

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Water quality is directly impacted by the landscape through which it travels. As such, land use, including summer annual and winter annual/perennial agriculture, has dramatic influence on the water quality of downstream aquatic and terrestrial ecosystems. I examined the impact of agricultural land use on water quality through two projects, one at a watershed scale and one at a field scale. In my first project, I investigated the impact of agricultural land use and climate on water quality in 13 HUC10 watersheds across Nebraska using public data from US Geological Survey (USGS), US Department of Agriculture National Agricultural Statistics Service …

Remediation Strategies To Reduce Heavy Metal Uptake In Lettuce Grown In Contaminated Urban Soil, Ryley Thomas

UCARE Research Products

Urban soils are increasingly used to produce food for local consumption, which requires at the same time management strategies that prevent the plant uptake of potentially present contaminants. This study was conducted to test different soil amendments for their ability to retain lead (Pb) and arsenic (As) within the soil matrix. The analyzed soil was taken from a potential community garden lot near a railroad in Lincoln, NE where elevated concentrations in Pb and As had been detected. Ponderosa pine biochar and spent coffee grounds were used as soil additives because of their documented chemical reactivity towards soil cations or …