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Creators/Authors contains: "Konar, Megan"

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  1. Free, publicly-accessible full text available August 21, 2026
  2. Abstract Global agricultural trade, production, and harvested area have steadily increased between 1961 and 2021. In this paper, we construct, decompose, and compare various measures of global physical crop yield that rely on countries’ crop area, production, and trade weights that vary over time. We document how the composition of exports and imports irrespective of the particular drivers of globalization is skewed towards higher crop yields compared to the changing international patterns of countries’ production as evidenced by the distribution of harvested area and production. We also document how the physical yield of exporting countries has consistently surpassed that of importing countries, indicating as well how a globalized world in which countries can trade and alter the pattern of crop production offers a way to ensure that worldwide higher-yield crops are being consumed. As such, the increasingly globalized agricultural sector with its many drivers of trade substitutes for and/or complements efforts to close the yield gap by upgrading countries crop production methods. For the exercise, we use national-scale data for 60 years from the Food and Agricultural Organization of the United Nations. 
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    Free, publicly-accessible full text available July 25, 2026
  3. Free, publicly-accessible full text available April 1, 2026
  4. Abstract This analysis quantifies the network dynamics, geographic concentration, and disparities in perishable food supply networks for temperature-controlled food shipments in the United States. The United States forms the core of global food systems and produces more high-quality data for network analysis than most other countries. We use the 2017 US Census Commodity Flow Survey and other publicly available data to derive empirical results from the Food Flow Model for perishable meats and perishable prepared foods. We identify the top ten counties for perishable food distribution and find that the Los Angeles and Chicago regions support the greatest volumes of perishable food movements. States that largely exist outside national perishable food networks are Arizona, Michigan, Montana, North Dakota, Texas, and West Virginia. Our analysis of US data highlights the importance of certain counties, states, and regions in perishable food networks and suggests areas where interventions could improve systems’ functions by increasing access to markets for farmers and access to food for underserved communities, especially those in rural regions. 
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  5. Free, publicly-accessible full text available January 1, 2026
  6. Abstract Reducing wasted food has been identified as a key strategy to meet food security goals and attain human nutritional needs and food preferences in an equitable, sustainable, and resilient manner. Yet, mathematically modeling how reducing wasted food contributes to sustainability, equity, and resilience objectives, and the possible interactions and tradeoffs among these metrics, is limited by challenges to quantifying these characteristics. Using the process of convergent science, we develop a prototype wasted food model to evaluate how a set of common equity, sustainability, and resilience measures interact. We consider prevention (consumer education) and treatment (anaerobic digestion and composting) options for wasted food diversion from landfills. The model applies a convex nonlinear optimization to determine the allocation of wasted food to different management alternatives, optimizing for economic (net cost), sustainability (emissions reductions or energy savings), or equity (distribution of per-capita cost or emissions reduction impacts). The model developed in this research is available online as open-source code for others to replicate and build upon for future studies and analysis. Our findings illustrate that optimal wasted food management alternatives may vary when targeting different metrics and that strategies promoting cost-effectiveness may be in tension with sustainability or equity goals and vice versa. The implications of this study could be used by policy makers to evaluate how wasted food reduction measures will impact sustainability, equity, and resilience goals. 
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    Free, publicly-accessible full text available April 1, 2026
  7. This dataset provides estimates of total Irrigation Water Use (IWU) by crop, county, water source, and year for the Continental United States. Total irrigation from Surface Water Withdrawals (SWW), total Groundwater Withdrawals (GWW), and nonrenewable Groundwater Depletion (GWD) is provided for 20 crops and crop groups from 2008 to 2020 at the county spatial resolution. In total, there are nearly 2.5 million data points in this dataset (3,142 counties; 13 years; 3 water sources; and 20 crops). This dataset supports the paper by Ruess et al (2024) "Total irrigation by crop in the Continental United States from 2008 to 2020", Scientific Data, doi: 10.1038/s41597-024-03244-w When using, please cite as: Ruess, P.J., Konar, M., Wanders, N., and Bierkens, M.F.P. (2024) Total irrigation by crop in the Continental United States from 2008 to 2020, Scientific Data, doi: 10.1038/s41597-024-03244-w 
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  8. Abstract Global grain trade plays a key role in food security. Many nations rely on imported grain to meet their dietary requirements. Grain imports may be at risk due to weather shocks, economic crises, or international conflicts. Countries aim to balance import risk with the expected return of their grain supplies. This research brings these dual objectives together in an innovative modern portfolio theory framework. Modern portfolio theory provides a set of concepts to formulate the trade-off between risk and expected return in national grain imports. Using Markowitz’s mean-variance optimization model, we identify opportunities to reduce risk in existing national grain import accounts, without increasing costs under realistic supply mass constraints of trade partners. Several major grain importers may be able to reduce risk in their grain imports without increasing cost, such as wheat imports in Egypt, maize imports in Vietnam, and rice imports in Saudi Arabia. However, some countries would indeed have to pay more to achieve more stable grain supplies, such as wheat imports in Turkey. This study provides a framework to quantify the different costs, benefits, and levels of risk in grain trade that can inform future research and decision-making. 
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  9. Abstract We provide a dataset of irrigation water withdrawals by crop, county, year, and water source within the United States. We employ a framework we previously developed to establish a companion dataset to our original estimates. The main difference is that we now use the U.S. Geological Survey (USGS) variable ‘irrigation — total’ to partition PCR-GLOBWB 2 hydrology model estimates, instead of ‘irrigation — crop’ as used in previous estimates. Our findings for Surface Water Withdrawals (SWW), total Groundwater Withdrawals (GWW), and nonrenewable Groundwater Depletion (GWD) are similar to those of prior estimates but now have better spatial coverage, since several states are missing from the USGS ‘irrigation — crop’ variable that was originally used. Irrigation water use increases in this study, since more states are included and ‘irrigation — total’ includes more categories of irrigation than ‘irrigation — crop’. Notably, irrigation in the Mississippi Embayment Aquifer is now captured for rice and soy. We provide nearly 2.5 million data points with this paper (3,142 counties; 13 years; 3 water sources; and 20 crops). 
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  10. Abstract The United States and China are key nations in global agricultural and food trade. They share a complex bilateral agri-food trade network in which disruptions could have a global ripple effect. Yet, we do not understand the spatially resolved connections in the bilateral US–China agri-food trade. In this study, we estimate the bilateral agri-food trade between Chinese provinces and U.S. states and counties. First, we estimate bilateral imports and exports of agri-food commodities for provinces and states. Second, we model link-level connections between provinces and states/counties. To do this, we develop a novel algorithm that integrates a variety of national and international databases for the year 2017, including trade data from the US Census Bureau, the US Freight Analysis Framework database, and Multi-Regional Input-Output tables for China. We then adapt the food flow model for inter-county agri-food movements within the US to estimate bilateral trade through port counties. We estimate 2,954 and 162,922 link-level connections at the state-province and county-province resolution, respectively, and identify core nodes in the bilateral agri-food trade network. Our results provide a spatially detailed mapping of the US–China bilateral agri-food trade, which may enable future research and inform decision-makers. 
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