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Agricultural Soil Erosion and Carbon Cycle Observations in Iowa: Gaps Threaten Climate Mitigating Policies

IA

University of Iowa/NASA Science Mission Directorate

In Iowa and most of the Midwest, increased variability between climate extremes (e.g., floods and droughts) coupled with intense agricultural activities to support our food and fuel needs are significantly shaping the carbon budget in the region. Most large-scale carbon budgets suggest that the Midwest can be a significant carbon sink, if the right management is practiced, but the full extent of this potential is unknown. The implications of agriculture management (till vs. no-

till) on carbon fluxes are not well understood. Also, the role of tiles on carbon losses remains open. This work addresses this specific issue. In addition, it provides some unique data for calibrating NASA’s global models for intensively managed eco -systems. These data are lacking. To our knowledge this is one of the few projects that systematically examines the collective role of runoff and tillage induced erosion on SOC redistribution and CO2 fluxes using different scaling approaches (bottom up and top down) combined with direct in-situ flux and biogeochemical observations. To help address these needs, our NASA EPSCoR team is investigating the impact of land-use change and associated agricultural practices on soil organic carbon (SOC) sequestration potential to provide better estimates of future CO2 trends within the region. In collaboration with NASA and USDA researchers, our team has developed a twopronged approach (bottom-up, top-down). The bottom-up approach explores the relationship between land-use change and CO2 so we can model better the effects of soil erosion on the SOC movement across the landscape and improve carbon budgets in Iowa. The top-down approach lets us look at the carbon cycle at multiple scales to see how sensitive the larger, regional scale carbon observations and predictions are to the carbon emissions from different land management practices under variable climate conditions. The comparison between the bottomup and top-down model will lead to a more holistic approach allowing us to identify areas of improvement for the larger scale models. To complete this work, we are incorporating information from the NSFsupported Intensively Managed Landscape Critical Zone Observatory, the recently installed NOAA tall tower observatory in West Branch, IA, and the long-term, field observations at USDA sites. NASA benefits from this EPSCoR research program are ample as we are providing improved understanding of how soil and atmospheric measurements taken at local and regional scale can be used to improve the biogeochemical models critical to NASA’s forecasts of atmospheric composition, land cover, and climate at decade-to-century time scales. Thanos Papanicolaou, Science PI, formerly of University of Iowa, now at University of Tennessee

www.nasa.gov/epscor/stimuli

NASA Technical Monitor: Ransook C. Evanina, Glenn Research Center

NASA EPSCoR Stimuli 2014-15

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EPSCoR Stimuli 2014-15  

NASA Office of Education’s Aerospace Research & Career Development (ARCD) is pleased to release NASA EPSCoR Stimuli, a collection of univers...

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