The Vital Role of Soil Health for Drought Resilience in Midwest Crops
Keeping the soil healthy is one way Midwest farmers can mitigate the risks of droughts as climate change heats up. Drought hits the Midwest economy hard, impacting crops grown for ethanol production and animal feed in addition to human food. Scientists have warned that climate change will lead to more summer droughts and warmer winters in the Midwest in the years to come, altering crop growth cycles and necessitating innovative agriculture and soil management practices.
As a supplier of specialty fertilizer products, my team has the privilege of speaking with farmers about traditional and inventive soil health solutions. Confronted with the difficulties of a drier environment, one thing they agree on is that healthy soil handles drought better.
Healthy Soil Bolsters Drought Tolerance
According to the Midwest Row Crop Collaborative and the University of Notre Dame's Environmental Change Initiative, improving soil health through regenerative farming practices can strengthen climate resilience across the agricultural system, including resistance to drought conditions. Let’s take a closer look at how healthy soil promotes better drought performance in row crops.
Soil Water-Holding Capacity
Healthy soils with good structure and high organic matter content have a greater ability to absorb and retain moisture, serving as a buffer against drought. Soil organic matter acts like a sponge, soaking up and holding water during wet periods and slowly releasing it during dry spells. Both qualities help row crop plants access moisture more consistently, reducing stress and yield losses during drought periods.
Soil Structure and Infiltration
So, what defines good soil structure? Healthy soils have a well-developed, balanced composition of mineral and organic elements with stable aggregates and pore spaces that facilitate water infiltration and movement. This structure allows rainwater to penetrate the soil more effectively, reducing surface runoff and increasing the amount of water available for plant uptake. In contrast, compacted or degraded soils with poor structure can lead to increased surface runoff and decreased water infiltration, exacerbating the effects of drought.
Decreased Compaction and Increased Aeration
Compacted soils restrict root growth, water infiltration and air exchange, making plants more susceptible to drought stress. Practices like no-till or reduced tillage, cover cropping and incorporating organic matter can alleviate compaction and improve soil structure.
Improved aeration in healthy soils allows roots to grow deeper, accessing moisture reserves in the subsoil during dry periods. The Sustainable Farming Association's Midwest Soil Health Summit highlighted how Minnesota farmers have experienced these benefits.
Organic Matter and Nutrient Availability
Soils rich in organic matter improve water-holding capacity and enhance nutrient availability and cycling. During drought conditions, plants with access to sufficient nutrients are better equipped to withstand stress and maintain growth and productivity. Healthy soils with abundant organic matter can steadily supply nutrients, even when water is limited, supporting plant growth.
Microbial Activity and Soil Biology
Healthy soils harbor a diverse community of microorganisms, including bacteria, fungi and other soil biota. These microorganisms play crucial roles in nutrient cycling, soil aggregation and plant-soil interactions. During drought periods, an active and diverse soil microbial ecosystem helps thirsty plants access water and nutrients more efficiently, enhancing their ability to cope with water stress.
Ag Industry Perspectives
The importance of soil health for drought resilience is widely recognized by farmers, investors and scholars. For example, the Chicago Federal Reserve Bank's analysis of climate change risks to Midwest agriculture acknowledges the potential for improved soil management practices to mitigate the adverse impacts of climate change on productivity.
Healthy soils with good structure, high organic matter content and active microbial communities are essential for enhancing drought resilience in row crop farming, particularly in the Midwestern U.S. By improving water-holding capacity, infiltration, nutrient availability and soil biology, healthy soils can temper the impacts of drought and support sustainable productivity in the face of changing climate conditions.
