Food security in a changing climate starts with managing soil water repellency

Abstract

Soil water repellency (SWR) is caused by hydrophobic organic compounds and is exacerbated during warmer temperatures and dry periods. SWR can have various detrimental effects, including limited wetting capabilities, reduced soil infiltration and hydraulic conductivity, and decreased plant available water, ultimately affecting crop yield. Conventional on-farm practices and soil health management strategies are implemented to cultivate healthy, productive lands. However, these practices and strategies impact SWR differently. Considering these strategies and the current understanding of factors contributing to SWR and climate change predictions, there is a strong potential that SWR occurrence and severity will increase in the future, which will impact food security. Current climate change models used to predict crop yields do not account for climate change induced SWR or how management practices and strategies influence SWR. To address this issue, this article reviews the impact of conventional on-farm practices and soil health management strategies on SWR and crop productivity, particularly in the context of predicted increasing temperatures and extreme precipitation events due to climate change. Building a robust climate change predictive model for crop yield will require understanding sub-critical SWR and adapting modern biomarking spectral and chemometric analyses to determine the repellency potential of inputs (amendments and plants), not just the soil. Once determined, this information can be used to assist farmers in making management decisions that will increase agroecosystem and livelihood sustainability and subsequently reduce food insecurity.

Keywords

• Soil water repellency
• Soil health
• Climate change
• Soil management
• Food security