Saturday, August 25, 2018

Carbon Capture: Soil health

Topsoil across the land areas of the planet holds substantially more carbon than the entire atmosphere, and over the past several hundred years we have released at least 50 percent of the carbon formerly held by soils into the air. This is primarily because of tilling, which disturbs the deeper soils and kills the roots and fungi which reside there. Tilling is necessary for modern agricultural practices using fertilizer and insecticides, which can improve yields substantially until the soil has become substantially depleted of carbon and gradually less productive. Much farmland around the world now is stuck in a local maxima: stopping tilling and allowing the soil to recover would eventually result in improved yields, but only after a few years of very poor harvests.

It is estimated that regenerating depleted land can absorb two to five tons of CO2 per acre per year, for about ten years. Done at scale, regenerative agriculture could absorb tens of gigatons of CO2 per year. For perspective, current human emissions are approximately 36 gigatons per year. Improving soil health could offset a nontrivial fraction of current emissions or, in conjunction with other methods to reduce new emission, pull previously emitted carbon from the air.

Companies in this technology space

  • Regen Network provides tools to gather and analyze data for soil health in regenerative agriculture, silvopasturing, and other practices to improve ecological health. It also provides a trading platform to invest and fund these developments.
  • COMET-Farm at Colorado State University tracks data entered by farms to estimate the levels of carbon stored, plus other factors relating to soil health.