Conserving soil carbon resources while transitioning to a C negative ‘bioenergy with carbon capture and storage’ (BECCS) economy is necessary for meeting global climate targets, but can have unintentional effects on other ecosystem services including biodiversity. We must understand interactions among food, water, energy, biodiversity, and social systems (FWEBS) at regional scales as we seek to meet global climate imperatives. The FWEBS nexus has changed rapidly in agricultural ecosystems, sometimes to the benefit of climate services. For example, parts of the Canadian Prairie Provinces have cooled by up to 2 °C during summer since the 1970s. This cooling is due in part to a reduction in the practice of keeping fields fallow during summer (hereafter ‘summerfallow’) on atmospheric boundary layer processes: summerfallow has declined by some 23 Mha from the 1970s until the present across the U.S. and Canada. In addition to climate impacts, replacing summerfallow with no-till cropping systems usually results in soil carbon and economic benefits, a ‘win-win-win’ scenario. However, trends away from conservation reserve program (CRP) lands have hindered biodiversity protection. FWEBS interactions in the northern North American Great Plains remain poorly quantified, which limits our ability to forecast coupled human/natural system dynamics.
Here, we use eddy covariance measurements to demonstrate that summerfallow results in carbon losses during the growing season of the same magnitude as carbon uptake by winter and spring wheat, on the order of 100 – 200 g C m-2 per growing season. We use eddy covariance energy flux measurements to model atmospheric boundary layer and lifted condensation level heights and convective precipitation, and demonstrate that regional increases in atmospheric moisture have made convective precipitation more likely. As a consequence, differences in modeled convective precipitation dynamics over native grasslands and crops is minor, suggesting that biodiversity conservation can play a beneficial role in the regional climate system, noting excess recent precipitation across parts of the Great Plains. We finish by discussing scenarios that incorporate bioenergy crops in a BECCS framework in the U.S. Upper Missouri River Basin and resulting FWEBS consequences to better manage Earth system and ecosystem services in a rapidly changing climate.