Fellow 2020-21

Kaiyu Guan

Natural Resources & Environmental Sciences

guan imageEnsuring Co-Sustainability of Food Production and Environmental Quality in the US Midwest Agroecosystems

Over the past two centuries, the US Midwest has transformed from natural prairie/wetlands to fertile croplands that currently produce about one-third of global corn and soybeans. Such landscape transformation by human activities through extensively subsurface "tiling" (drainage piping) and intensified uses of fertilizer and other inputs has also created significant concerns in environmental sustainability. With further stress from climate change, could the US Midwest remain the global food basket in the next 100 years? How can we ensure co-sustainability of food production and environmental quality in this landscape? Carbon (e.g. crop productivity), hydrology (both water quantity and quality), and nutrient cycles are closely intertwined in this landscape from the field/headwater scale to the whole river network and continental scales (greater Mississippi river basin). Thus, a "system" analysis of the complex feedbacks and interactions is required to assess potential adaptations in the US Midwest agroecosystem. This project adopts a “system” view to holistically model and quantify the coupled “food-water-nutrient nexus” for the US Midwest agroecosystems.

Specifically, the project will develop a coupled land-river model, and integrate field-level collected data and remote sensing measurements to constrain the model. This model will be applied to farmlands for the three I-states (Illinois, Iowa, and Indiana) in the US Midwest. In particular, tile drainage extent and drainage strength will be estimated in a spatially explicit manner at the regional scale for the study domain, by a new model-data fusion approach based on ecohydrological processes. The project will develop a coupled land-river network model (ecosys-THREW) to quantify feedbacks/interactions among the water cycle, nitrogen cycle, and crop production across spatial scales in this agroecosystem, as well as to assess the potential of promising human management practices to allow co-sustainability of food production and environment quality in the US Midwest.