The state of sustainable agriculture and agroecology research and impacts: A survey of U.S. scientists

A growing body of research suggests that although sustainable agriculture, particularly agroecology, can address challenges such as those related to climate change, ecosystem services, food insecurity, and farmer livelihoods, the transition to such systems remains limited. To gain insight into the state of U.S. sustainable agriculture and agroecology, we developed a 28-question mixed-method survey that was administered to scientists in these fields. Respondents (N=168) represented diverse locations, institutions, and career stages. They offered varied definitions of sustainable agriculture, with 40% considering economic and social well-being to be core components. Respondents identified the amount and duration of public research funding as important obstacles to conducting research on sus- tainable agriculture (85% and 61%, respectively). Further, most expressed challenges in communi- cating findings beyond academia, including to the media and policymakers, potentially limiting the impacts of such research. However, respondents expressed satisfaction in several areas, including relationships with community members (81%) and local producers (81%), and interest from students (80%) and research communities (73%), suggesting positive momentum in this field. Earlier versus later career scientists rated research on “human dimensions” as more important, expressed greater concerns over career stability, and were less satisfied with opportunities for policy engagement. Results imply that greater public investments, particularly fostering human dimensions, could support a transition to agroecology and its associated benefits

Investigation of Ligand Field Modifications on Lanthanide(III) Complexes: Structure, Magnetism and Optical Properties

Diese Arbeit befasst sich mit Lanthanoidkomplexen, ihrer Struktur, ihrem Magnetismus und ihren optischen Eigenschaften. Scandium, Yttrium und die Lanthanoide von Lanthan bis Lutetium sind die Elemente der Seltenen Erden. Sie weisen im Allgemeinen ähnliche chemische und physikalische Eigenschaften auf. Beginnend mit Cer und endend mit Lutetium werden die 4f-Orbitale nach und nach gefüllt. Diese Elemente nehmen im Allgemeinen eine stabile Oxidationsstufe von +3 an. Der erste Schwerpunkt dieser Arbeit liegt auf den molekularen Strukturen von Lanthanoidkomplexen. Es wurde ein Ligandensystem entworfen, das leicht modifiziert werden kann, um zu verstehen, wie sich Änderungen in der Struktur des Liganden auf die Geometrie der resultierenden Komplexe auswirken. Die Änderungen am Liganden wurden bewusst klein gehalten, um die Auswirkungen dieser Änderungen besser zu verstehen. Der zweite Schwerpunkt liegt auf den magnetischen Eigenschaften dieser Komplexe. Da Dy(III)-Ionen aufgrund ihrer Kombination aus einem starken uniaxialen magnetischen Moment und einem hohen mJ-Wert von ±15/2 am häufigsten für Lanthanoid-basierte Einzelmolekülmagnete (SMMs) verwendet werden, liegt der Schwerpunkt dieser Arbeit auf der Synthese von Dy(III)-Komplexe. Magnetische Untersuchungen von fünf zweikernigen Dy(III)-Verbindungen wurden an einem SQUID-Magnetometer durchgeführt und AC-Messungen wurden durchgeführt, um das SMM-Verhalten besser zu verstehen. Drei der vorgestellten Verbindungen zeigen schnelle Relaxationsprozesse und eine zeigt kein SMM-Verhalten. Andererseits erweist sich die Verbindung [Dy2(L2)2(CH3COO)4(CH3OH)2] (6) als ausgezeichnetes SMM. Der dritte Schwerpunkt liegt auf den optischen Eigenschaften solcher Lanthanoidkomplexe. Umfangreiche Messreihen wurden zum optischen Absorptionsverhalten des Liganden 2,6-(1-(2-(1H-Benzimidazol-2-yl)hydrazineyliden)ethyl)pyridin (HL7) und seiner Komplexe mit allen Lanthanoidionen durchgeführt

AGRO 204: Resource Efficient Crop Management

Resource Efficient Crop Management (Agro 204) is a high enrollment course taken by a diverse range of student majors across the College of Agricultural Sciences and Natural Resources (CASNR) at the University of Nebraska-Lincoln. Learning outcomes focus on teaching crop management principles and processes, systems-thinking, data analysis, synthesizing current information, and evidence-based decision-making. This benchmark portfolio critically assesses student learning toward these outcomes, with an emphasis on a particular assignment that required students to work with the farming simulation platform, APSIM. The Agricultural Production Systems sIMulator (APSIM) is a freely available computer program that is an internationally recognized simulator of agricultural systems. In five course periods throughout the semester as well as through online videos and materials, students were introduced to the APSIM platform. The assignment assessed in this portfolio required students to set up their own “experiment” with a hypothesis that could be performed and analyzed using the APSIM platform. Ninety-one percent of student responses in the assignment demonstrated that students were able to explain a process underpinning crop management (such as differences in crop water use with different crop rotations) which was a major goal of this assignment. In addition, a post-assignment survey found that 67% percent of students agreed with the statement that “The simulations helped me understand the interaction of controllable and uncontrollable factors that affect yield.” Based on the simulations, students reported how they discovered a range of new potential management understandings, from the impact of planting dates, soil types, climate change and crop rotations on various agronomic outcomes such as crop yield or nutrient loss. Many students further reported gaining awareness of the software and related platforms such that they could envision using such a platform to recommend crop management decisions to others or for use with their own farming operations. A pre- and post-assignment survey revealed that students gained confidence in hypothesis development, data analysis, and evidence-based decision-making from the course. Many students reported challenges with the computer program, and a number of improvements will be made in the future to facilitate student experiences and learning

Where do students do their shopping these days?

Abbot Pennings answers a question about student shopping habits, archived from the SNC website

Training future agriculture professionals in landowner–tenant conservation decision-making

The landowner–tenant relationship is important to the implementation of conservation on agricultural lands. Women own or co-own a significant portion of U.S. farmland yet are underrepresented in conservation research. The next generation of agriculture professionals can benefit from first-hand experience in assisting women landowners and their tenants in navigating the complexities of conservation decision-making. This article analyzes undergraduate student perceptions of landowner–tenant relationships in conservation management through their engagement in case studies with women landowner–tenant pairs in the Western Corn Belt. Student groups were asked to complete a management improvement plan that both incorporated the agronomic and conservation goals discussed by the landowners and tenants, following a field trip and interviews with the landowners, tenants, and other key stakeholders. Assessment data included a quantitative survey of career goals and conservation attitudes, qualitative reflections at start and end of course, and autoethnographic observations. The case studies presented students with new knowledge challenging previously held assumptions, leading some students to reconsider landowner–tenant relationships and conservation decision-making. However, students returned to existing gendered norms and production-oriented stereotypes when applying this knowledge in real-world farm management plans. Although students gained firsthand valuable experience from the case studies, a one-semester case study was insufficient to significantly shift student perceptions. We recommend that more curricular experiences incorporate the complexities of agricultural decision-making to better equip future agricultural professionals with skills to ensure environmental and social sustainability outcomes

Development of a process for producing ribbon shaped boron filaments

A ribbon-shaped boron filament with a tensile strength of 138 KN/sq cm (200 ksi) was investigated. The investigation was carried out using both carbon and tungsten as substrate materials. No satisfactory results were obtained utilizing uncoated, copper-plated or silicon carbide coated tungsten ribbon substrates. Carbon ribbon substrates were prepared by pyrolysis of stretched polyimide tape. A severe deposition gradient occurred in all dc reactor experiments due to convective cooling at the edge of the substrate that resulted in a weak, nonuniform filament. RF heating, however, completely eliminated this gradient problem and a 90 cm (35.5 in.) long boron ribbon was produced at .85 cm/sec (100 ft/hr) using a frequency of 40.68 megahertz. This boron ribbon, however, exhibited a light-bulb effect during deposition to 59 KN/sq cm (85.7 ksi) were obtained from this ribbon. Several silicon carbide ribbon shaped filaments were also produced during this investigation by decomposition of CH3SiHCl2 onto carbon substrates. Contrary to the boron work, silicon carbide ribbon was readily prepared in dc static reactors. A very uniform and smooth deposition was obtained with strengths up to 71.1 KN/sq cm (103.5 ksi)

Leveraging agroecology for solutions in food, energy, and water

Global agriculture is facing growing challenges at the nexus of interconnected food, energy and water systems, including but not limited to persistent food insecurity and diet-related diseases; growing demands for energy and consequences for climate change; and declining water resources, water pollution, floods and droughts. Further, soil degradation and biodiversity loss are both triggers for and consequences of these problems. In this commentary, we argue that expanding agroecological principles, tools, and technologies and enhancing biological diversity can address these challenges and achieve better socioeconomic outcomes. Agroecology is often described as multi- or transdiscplinary, and applies ecological principles to the design and management of agricultural systems through scientific research, practice and collective action. While agroecology has roots in the study of food systems, agricultural land use has many direct and indirect linkages to water and energy systems that could benefit from agroecological insights, including use of water resources and the development of bio-based energy products. Although opportunities from the science and the practice of agroecology transcend national boundaries, obstacles to widespread adoption vary. In this article, we therefore focus on the United States, where key barriers include a shortage of research funds, limited supporting infrastructure, and cultural obstacles. Nevertheless, simply scaling up current models of agricultural production and land use practices will not solve many of the issues specific to food related challenges nor would such an approach address related energy and water concerns. We conclude that a first critical step to discovering solutions at the food, energy, water nexus will be to move past yield as a sole measure of success in agricultural systems, and call for more holistic considerations of the co-benefits and tradeoffs of different agricultural management options, particularly as they relate to environmental and equity outcomes

SEABEM: An Artificial Intelligence Powered Web Application To Predict Cover Crop Biomass

SEABEM, the Stacked Ensemble Algorithms Biomass Estimator Model, is a web application with a stacked ensemble of Machine Learning (ML) algorithms running on the backend to predict cover crop biomass for locations in Sub-Saharan. The SEABEM model was developed using a previously developed database of crop growth and yield that included site characteristics such as latitude, longitude, soil texture (sand, silt, and clay percentages), temperature, and precipitation. The goal of SEABEM is to provide global farmers, mainly small-scale African farmers, the knowledge they need before practicing and benefiting from cover crops while avoiding the expensive and time-consuming operations that come with blind on-site experimentation. The results were derived from comparing ten different ML algorithms, demonstrating the dominance of ensemble models. The top-performing models - Gradient Boost Regressor, Extra Trees Regressor, and Random Forest Regressor - were stacked together into one model to power the SEABEM web application. As the project is open-sourced on a GitHub repository, the GitHub community is available for others to improve the project. The SEABEM web application is also accessible and valuable to anyone worldwide as its development came from global data