The amount of carbon working behind the scenes in your ground can benefit soil quality, crop health and ultimately, plant performance.
Like nitrogen, carbon also has a natural cycle at work in our environment, which is why it is central to so many actions we take in agriculture. When we’re measuring the organic matter in our soil, that’s carbon. When we’re trying to cut back on erosion, that’s often a carbon issue. When our corn is taking up all that we put down and growing in leaps and bounds – carbon is working in that process as well.
Holding onto more carbon in the soil (and less being lost to the atmosphere as CO2) means that you’re increasing your soil’s organic carbon and overall organic matter, which is the main source of energy for soil microorganisms that help improve biological activity in your soil. That’s why carbon is also one of the most important indicators of soil quality.
There is a direct relationship between carbon and nitrogen, a C to N ratio at which living things break down and decompose, which indicates how “busy” (i.e. healthy and active) your soils are. As carbon begins to settle into the soil, improved soil structure is one of the first big benefits you’ll see.
As organic matter increases, so does a soil’s water and nutrient holding capacity. Improving in water infiltration is also a significant combatant to erosion and soil crusting. Increased organic matter can also help improve overall crop health through the increased diversity and fertility in the soil biome, while binding pesticides and helping slow the spread of disease in the crop.
Soil carbon helps improve water quality as well – as decreased runoff means less sediment in the water system. Improved air quality is another a plus. Better soil gives dust and other particulates that are often carried by wind a place to settle.
So, how can you better manage carbon alongside nitrogen, and make good use of the carbon cycle for your crops? Here are a few of the current practices.
By reducing disturbance – through no till and reduced tillage practices – we can keep carbon in the soil, instead of gassing off or washing away.
By taking advantage of high residue and high biomass crops, we increase the amount of organic matter in the soil profile, giving the available carbon more to hold on to.
Cover crops can play a key role in this process as well. After each year’s crop is removed, cover crops continue the biological process of securing carbon, while reducing erosion and improving the soil structure.
By replanting or reforesting land that is no longer in use, we can turn land that sits bare into a flourishing space that keeps air, water, and the carbon process grounded.
Most of our crops have a one-year turnaround, which limits the amount of time they have to secure carbon while increasing the time a field might lay empty. Employing a perennial cropping system where possible on certain acreage over an annual cropping system could help provide more soil carbon for the next crop planted on that ground.