Beyond Carbon Neutral Seminar Series: John Field, Colorado State University
Title: What can ecosystem models tell us about carbon-negative bioenergy?
After years of slow progress on achieving greenhouse gas emissions reductions, most climate stabilization scenarios now assume significant future ability to capture and store ambient atmospheric CO2, usually via photosynthesis and carbon sequestration in vegetation, soils, or geological storage. However, there is much controversy around the ability of bioenergy technologies to achieve net climate mitigation once changes in ecosystem carbon storage within and outside of the bioenergy supply chain are considered. While bioenergy sustainability has traditionally been studied through an engineering lifecycle assessment lens, fully addressing these emergent critical sustainability challenges requires broad interdisciplinary collaboration between engineers, ecologists, and economists.
In this seminar we will explore what ecosystem modeling might contribute to understanding bioenergy system productivity and net climate mitigation value, providing a key intermediary link between plot-level field observations and broader supply chain assessments. We will consider two case studies:
- Switchgrass production around a cellulosic biorefinery in a mixed-use Great Plains landscape, including soil carbon and nitrous oxide emission impacts
- Harvesting mountain pine beetle-killed trees in the Rocky Mountains for co-production of biofuels and biochar, including feedbacks to landscape-scale carbon storage
The seminar will emphasize ecosystem model calibration and validation with experimental data, extrapolation to biorefinery-relevant scales across heterogeneous landscapes, and use of model outputs for integrated environmental-economic assessments grounded in likely landowner practices.
John Field is a research scientist at the Colorado State University Natural Resource Ecology Laboratory. He studies the climate mitigation potential of bioenergy systems at the intersection of ecosystem process modeling, lifecycle assessment, and sustainable land use planning. He has contributed to research projects on switchgrass cultivation in the Great Plains, biochar production in the Colorado Front Range, gasification of agricultural wastes in Southeast Asia, and identification of marginal lands across the US. He is also the project manager for the Bioenergy Alliance Network of the Rockies (BANR), a USDA-NIFA CAP consortium studying the viability and sustainability of utilizing beetle-killed wood as a feedstock for carbon-negative bioenergy production. He received his BSc from Case Western Reserve University, and worked in the private sector doing R&D on small-scale solid oxide fuel cell power systems prior to pursing a PhD through the CSU Department of Mechanical Engineering as a fellow in the Multidisciplinary Approaches to Sustainable Bioenergy NSF IGERT program. When John isn’t writing or coding, he likes to be hiking or skiing up in the mountains of Colorado.