Biochar for Reduction of Agricultural Water Strain

Abstract

Biochar, a carbon-rich charcoal substance made from pyrolyzed biomass, is emerging as a potential material for climate change mitigation and soil improvement. Historically used to improve soil fertility, it is now being looked to as a negative emissions technology with potential for widespread agricultural use. Biochar has been documented as improving soil nutrient retention, water holding capacity, and crop yield while also subverting greenhouse gas emissions that decomposing biomass would otherwise release. Using a probabilistic soil moisture model and aggregating data on soil water retention curves, this work builds on existing studies to model changes to the soil water balance. Two cases, reflecting California and the Midwestern United States, were considered for their important role in the agricultural industry and their unique climates and growing seasons. Although the results do not reveal significant reduction in agricultural water demand with biochar implementation, the work opens directions for future experimentation, and the model remains adaptable for case studies and incorporation of additional parameters. As agricultural demands increase and climate change threatens food security, this project can help inform decisions on biochar implementation.