Physical Sciences and Mathematics Commons^™

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 …

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 …

A Survey Of Dairy-Goat Keeping In Zanzibar, Tiffanie Stone, Charles A. Francis, L. O. Eik

Department of Agronomy and Horticulture: Faculty Publications

Dairy goats with improved genetics for milk production were recently introduced onto small-scale farms in Zanzibar through governmental and non-governmental projects. These projects were meant to support small-scale farmers by improving both income and household nutrition through milk production. No follow up had been conducted to understand what effects dairy goat keeping had on these small-scale farms, or how they could be improved. A survey of 193 dairy goat farmers in Zanzibar was conducted, including 30% and 60% of all dairy goat farmers on Unguja and Pemba, the two largest islands, respectively. The objective was to understand the impact keeping …

Transformative Education In Agroecology: Student, Teacher, And Client Involvement In Co-Learning, Charles A. Francis, Anna Marie Nicolaysen, Geir Lieblein, Tor Arvid Breland

Department of Agronomy and Horticulture: Faculty Publications

Educational methods have evolved rapidly in agroecology, which is a complex and holistic field without a long history or the formal tradition of any single academic discipline. Definitions of agroecology have evolved from its initial conception as a marriage of agriculture with ecology, to an aggregation of different paths including science, practices, and movements, and recently as a broad appreciation of the ecology of food systems. In contrast with traditional courses that begin with a history of the discipline and review the contributions of early leaders, we have embraced phenomenology to firmly establish roots in students’ learning through their experiences …

Urban Food Sovereignty: Urgent Need For Agroecology And Systems Thinking In A Post-Covid-19 Future, Ali Loker, Charles A. Francis

Department of Agronomy and Horticulture: Faculty Publications

The current COVID-19 pandemic has brought attention to challenges associated with our dominant industrial food system in the U.S. The general public now has more appreciation for farm workers and meatpacking employees, as well as those in grocery stores and in food transportation who are suddenly recognized as essential frontline workers. It apparently takes a crisis for us to focus clearly on the fragility of this system and the lives of people on whom we depend. In this commentary we discuss the definition of food sovereignty, how it manifests in urban areas, and how the COVID-19 pandemic can trigger viable …

Organic Agriculture Teaching And Learning In 2025: Transforming The Future Learning Landscape, Randa Jabbour, Charles A. Francis, Mary Barbercheck, Katharina S. Ullman

Department of Agronomy and Horticulture: Faculty Publications

University instructors are compelled to anticipate future changes in farming and food systems that will impact their students. Sixteen educators met in 2018 to envision the future of organic agriculture courses needed by 2025. Likely future global issues include food access, especially for people of limited economic means; climate change; and fossil fuel costs. Changes that will impact education are increasing demand for quality food, more organic production, and globalization of food systems due to consolidation. Probable course content changes are increasing focus on whole farm systems; designing for resilience in changing physical, economic, environmental, and political climates; and increasing …

Building Resilience In Social-Ecological Food Systems In Vermont, Kristine Lien Skog, Stine Elisabeth Eriksen, Christy Anderson Brekken, Charles A. Francis

Department of Agronomy and Horticulture: Faculty Publications

There is an expanding interest in Local Food Systems (LFSs) in Vermont, United States, along with a growing effort to create adaptive governance to facilitate action. In this case study, we investigate how adaptive governance of LFS can provide ideas and act as a catalyst for creating resilience in other social-ecological systems (SESs). By participating in meetings and interviewing stakeholders inside and outside the Vermont LFS network, we found that consumers were highly motivated to participate by supporting environmental issues, the local economy, and interactive communities, as well as building social relationships. Farmers experienced better income and increased respect in …

Effects Of Post Eviction Resettlement On Land-Use And Cover Change In Uganda’S Oil Exploration Areas, Joseph Ssekandi, John Mburu, Oliver Wasonga, Laban Macopiyo, Charles A. Francis

Department of Agronomy and Horticulture: Faculty Publications

Evaluation of the changes in land use and land cover change (LULCC) in respect to oil exploration across the Albertine region in Uganda has been focused around the exploration areas and protected areas, with no attention to the potential impacts of evictees’ activities on resettled areas. This study used LANDSAT images to analyze the land use and land cover changes (LULCC) among the period before eviction (2002 and 2005) at the climax of eviction and resettlements (2005-2011), and during the post-resettlement period (2011-2015) to quantify the impacts of resettlements on the environment. LANDSAT images were processed using ERDAS IMAGINE software …

Evaluating A Satellite-Based Seasonal Evapotranspiration Product And Identifying Its Relationship With Other Satellite-Derived Products And Crop Yield: A Case Study For Ethiopia, Tsegaye Tadesse, Gabriel B. Senay, Getachew Berhan, Teshome Regassa, Shimelis Beyene

Department of Agronomy and Horticulture: Faculty Publications

Satellite-derived evapotranspiration anomalies and normalized difference vegetation index (NDVI) products from Moderate Resolution Imaging Spectroradiometer (MODIS) data are currently used for African agricultural drought monitoring and food security status assessment. In this study, a process to evaluate satellite-derived evapotranspiration (ETa) products with a geospatial statistical exploratory technique that uses NDVI, satellite-derived rainfall estimate (RFE), and crop yield data has been developed. The main goal of this study was to evaluate the ETa using the NDVI and RFE, and identify a relationship between the ETa and Ethiopia’s cereal crop (i.e., teff, sorghum, corn/maize, barley, and wheat) yields during the main rainy …

Cover Crops And Ecosystem Services: Insights From Studies In Temperate Soils, Humberto Blanco-Canqui, Tim M. Shaver, John L. Lindquist, Charles A. Shapiro, Roger Wesley Elmore, Charles A. Francis, Gary W. Hergert

Department of Agronomy and Horticulture: Faculty Publications

Cover crops (CCs) can provide multiple soil, agricultural production, and environmental benefits. However, a better understanding of such potential ecosystem services is needed. We summarized the current state of knowledge of CC effects on soil C stocks, soil erosion, physical properties, soil water, nutrients, microbial properties, weed control, crop yields, expanded uses, and economics and highlighted research needs. Our review indicates that CCs are multifunctional. Cover crops increase soil organic C stocks (0.1–1 Mg ha^–1 yr^–1) with the magnitude depending on biomass amount, years in CCs, and initial soil C level. Runoff loss can decrease by up …

Food Webs And Food Sovereignty: Research Agenda For Sustainability, Charles A. Francis, Michelle Miller, Molly Anderson, Nancy Creamer, Michelle Wander, Jacob Park, Thomas Green, Brent Mccown

Department of Agronomy and Horticulture: Faculty Publications

Future food production will be constrained by the scarcity of fossil fuel and fresh water as well as increasing intensity and unpredictability of weather events and climate changes. The assurance of food security and equity for many consumers is complicated by concentration of ownership of land and other production resources, as well as a global corporate food systems model that is driven by profit at the expense of people and the environment. To assess potential alternatives to the contemporary global food chain, well focused research is needed on local food production and food webs where small- and midscale family farms …

The Essentials Of Economic Sustainability By John Ikerd [Book Review], Charles A. Francis

Department of Agronomy and Horticulture: Faculty Publications

Essentials of Economic Sustainability is the latest challenging statement on innovative economic philosophy from an alternative opinion leader John Ikerd, retired agricultural economist from University of Missouri, Columbia (Columbia, Missouri, United States). His perspective is that accelerating changes surrounding us require more than small adaptations, but rather a thoughtful reconsideration of basic principles about how the world works and our role in this dynamic reality. Ikerd paraphrases the challenge of the 1988 Brundtland Report of the United Nations that we must design strategies ‘to meet the economic needs of the present without diminishing economic opportunities for the future’ (page 1). …

Critical Research Needs For Successful Food Systems Adaptation To Climate Change, Michelle Miller, Molly Anderson, Charles A. Francis, Chad Kruger, Carol Barford, Jacob Park, Brent H. Mccown

Department of Agronomy and Horticulture: Faculty Publications

There is a growing sense of the fragility of agricultural production in the Global North and South and of increasing risks to food security, as scientific observations confirm significant changes in the Gulf Stream, polar ice, atmospheric CO₂, methane release, and other measures of climate change. This sense is heightened as each of us experiences extreme weather, such as the increasing frequency of droughts, floods, unseasonal temperatures, and erratic seasonality. The central research challenge before us is how global, national, regional, and local food systems may adapt to accelerating climate change stresses and uncertainties to ensure the availability, …

Cover Crop Mixtures For The Western Corn Belt: Opportunities For Increased Productivity And Stability, Samuel E. Wortman, Charles A. Francis, John L. Lindquist

Department of Agronomy and Horticulture: Faculty Publications

Achieving agronomic and environmental benefits associated with cover crops oft en depends on reliable establishment of a highly productive cover crop community. The objective of this study was to determine if cover crop mixtures can increase productivity and stability compared to single species cover crops, and to identify those components most active in contributing to or detracting from mixture productivity. A rainfed field experiment was conducted near Mead, Nebraska, United States, in 2010 and 2011. Eight individual cover crop species (in either the Brassicaceae [mustard] or Fabaceae [legume] family) and four mixtures of these species (two, four, six, and eight …

Effectiveness Of Grass Filters In Reducing Phosphorus And Sediment Runoff, Ahmed Al-Wadaey, Charles S. Wortmann, Thomas G. Franti, Charles A. Shapiro, Dean E. Eisenhauer

Department of Agronomy and Horticulture: Faculty Publications

Surface water contamination can often be reduced by passing runoff water through perennial grass filters. Research was conducted in 2006 to 2008 to evaluate the size of cool season grass filters consisting primarily of tall fescue (Festuca arundinacea Schreb) with some orchard grass (Dactylis glomerata L.) relative to drainage area size in reducing runoff sediment and phosphorus (P). The soil was Pohocco silt loam Typic Eutrochrepts with a median slope of 5.5%. The grass filters occupying 1.1 and 4.3% of the plot area were compared with no filter with four replications. The filters were planted in the V-shaped …

Agriculture And Food In Crisis: Conflict, Resistance, And Renewal [Book Review], Charles A. Francis

Department of Agronomy and Horticulture: Faculty Publications

Edited by Fred Magdoff and Brian Tokar. 2010. Monthly Review Press, New York, New York, United States. 348 p. Paperback, cloth US$ 75.00, paper US$ 18.95, ISBN-13 978-1-58367-226-6.

That doubling of food production over the next four decades will be needed to adequately nourish our human population is not news, but the incredible steps essential to achieve that goal and their political and social implications are less well reported. In this series of 16 essays edited by Fred Magdoff and Brian Tokar, several thoughtful specialists in global food issues explore the historical, biological, economic, energy, political and social dimensions of …

Cultivating A Movement: Excerpts From An Oral History Of Organic Farming And Sustainable Agriculture On California’S Central Coast [Book Review], Charles A. Francis

Department of Agronomy and Horticulture: Faculty Publications

Edited by I. Reti and S. Rabkin, 2011. University of California, Santa Cruz, Library, Santa Cruz, California, United States. 299 p., US$19.95, ISBN 9-780972-33431, paper.

Often the most compelling evidence for success of organic farming comes from the personal stories of farmers. Coupled with reports on the application of science in organics, the practical knowledge of people in the field provides a rich foundation for the ongoing growth of this intriguing sector of the food system. This collection of interviews by the staff of the Regional History Project is one unique activity of the University of California, Santa Cruz library, …

Increased Weed Diversity, Density And Above-Ground Biomass In Long-Term Organic Crop Rotations, Samuel E. Wortman, John L. Lindquist, Milton J. Haar, Charles A. Francis

Department of Agronomy and Horticulture: Faculty Publications

While weed management is consistently a top priority among farmers, there is also growing concern for the conservation of biodiversity. Maintaining diverse weed communities below bioeconomic thresholds may provide ecosystem services for the crop and the surrounding ecosystem. This study was conducted to determine if weed diversity, density and biomass differ within and among organic and conventional crop rotations. In 2007 and 2008, we sampled weed communities in four long-term crop rotations near Mead, Nebraska, United States using seedbank analyses (elutriation and greenhouse emergence) and above-ground biomass sampling. Two conventional crop rotations consisted of a corn (Zea mays) …

‘Food For Life’: Looking Beyond The Horizon, Charles A. Francis, John W. Doran

Department of Agronomy and Horticulture: Faculty Publications

Our real challenge appears to be anticipating what the major challenges and constraints will be to food production and distribution a decade or more into the future. This could be called ‘Beyond the Horizon’ thinking. Today there is little disagreement over the massive depletion on a global scale of two essential inputs to agriculture: fossil fuels and fresh water. We also recognize that phosphorus is found in concentrated form in only a few deposits in nature, and that agriculture is rapidly using this limited resource and dispersing it through harvested products and soil loss from fields in forms that make …

Farmers And Nature Conservation: What Is Known About Attitudes, Context Factors And Actions Affecting Conservation?, Johan Ahnström, Jenny Höckert, Hanna L. Bergea, Charles A. Francis, Peter Skelton, Lars Hallgren

Department of Agronomy and Horticulture: Faculty Publications

Farmers’ attitudes towards viability of specific conservation practices or actions strongly impact their decisions on adoption and change. This review of ‘attitude’ information reveals a wide range of perceptions about what conservation means and what the impacts of adoption will mean in economic and environmental terms. Farmers operate in a tight financial situation, and in parts of the world they are highly dependent on government subsidies, and cannot afford to risk losing that support. Use of conservation practices is most effective when these are understood in the context of the individual farm, and decisions are rooted in land and resource …

Does The Corn/Soybean Farmer Have Time For Alternative Crops? [Abstract], Lori A. Hoagland, Laurie Hodges, Glenn A. Helmers, James R. Brandle, Charles A. Francis

Department of Agronomy and Horticulture: Faculty Publications

Diversification of traditional row-crop farming in the Corn Belt is seen as advantageous in providing a wider economic base, decreasing economic risk associated with the link between commodity grain and cattle, increasing net farm income, and increasing biodiversity in the region. As farm size has increased to provide sufficient farm income, farm operations during the critical planting and harvesting windows are seen as limits to additional on-farm enterprises.

Agricultural Systems: Agroecology And Rural Innovations For Development [Book Review], Charles A. Francis

Department of Agronomy and Horticulture: Faculty Publications

To welcome yet another book on sustainable development, a reviewer must look for what is unique and what adds value to the volumes already published. In Agricultural Systems, editors Sieglinde Snapp and Barry Pound have assembled a collection of chapters that goes beyond the usual praise and criticism of the green revolution and the focus on economic development. Their book provides a first-hand story by people with lengthy experiences in the field, especially in Africa, who have developed and tested grassroots, participatory development approaches. The result is a valuable set of principles, strategies and case studies that paint a new …

Farming Systems Research/Extension And The Concepts Of Sustainability, Charles A. Francis, Peter E. Hildebrand

Department of Agronomy and Horticulture: Faculty Publications

Farming Systems Research and Extension (FSR/E) has strongly influenced the direction of agricultural development over the past two decades. Involving farmers, change agents and researchers, this participatory approach to technological improvement has evolved as an efficient means to develop individual components and more integrated systems that are uniquely suited to specific biophysical and socioeconomic conditions. Farmers with similar conditions and for whom specific recommendations are appropriate are grouped, in FSR/E, into identifiable Recommendation Domains. The technologies recommended conform with the biophysical and socioeconomic constraints that create environments within the domains, based on the philosophy that new technologies must conform with …

Microorganisms And Soil Structure, T. M. Mccalla, F. A. Haskins

Department of Agronomy and Horticulture: Faculty Publications

SUMMARY

Good stable soil structure is valuable for promoting the growth of plants and micro-organisms by permitting enhanced aeration and water penetration and by decreasing erosion under some conditions.

Micro-organisms influence water percolation through the soil. They may plug up soil pores with byproducts of growth and reduce water percolation. On the other hand, if a soil containing a large amount of microbial products is stirred and allowed to dry, then the percolation may be high.

Micro-organisms are involved in stabilizing soil structure by their products of decomposition and their cellular binding material, such as mycelia. Microorganisms differ greatly in …

Influence Of Various Factors On Aggregation Of Peorian Loess By Microorganisms, T. M. Mccalla, Francis A. Haskins, E. F. Frolik

Department of Agronomy and Horticulture: Faculty Publications

Soil structure is important in the attainment of adequate aeration for the aerobic microorganisms whose activities maintain such higher plant nutrients as sulfur, phosphorus, and nitrogen in a highly oxidized and thus readily available state. Good soil structure is also necessary for soil and water conservation, Under Nebraska conditions microorganisms and their decomposition products constitute a major source of soil-aggregating agents. The decomposition of crop residues and plant roots is important in the nutrition of these aggregating microorganisms. Other microorganisms, however, also utilize crop residues and plant roots, and they may decompose the aggregating agents as well, so that the …

Microorganisms And Soil Structure, T. M. Mccalla

Department of Agronomy and Horticulture: Faculty Publications

SUMMARY

Laboratory tests were made to determine the effectiveness of different compounds and microbial groups in increasing the stability of Peorian loess lumps against the action of falling water drops. The influence of these on percolation tests in the laboratory was also determined.

Many organic substances-dextrose, sucrose, starch, peptone, cullulose, and gum arabic-did not themselves contribute directly to soil-structure stability, though these substances do furnish energy material for soil microorganisms, which can convert them readily into either microbial tissue or decomposition products that increase soil-structure stability. Lignin, proteins, oils, fats, waxes, resin, and paraffin increased the stability of lumps of …