Editor’s note: This commentary is by Ron Krupp, of South Burlington, who is the author of “The Woodchuck’s Guide to Gardening” and “The Woodchuck Returns to Gardening.” and is working on his third Vermont garden book called, “The Woodchuck’s Guide to Landscape Plants and Ornamentals.”
It may come as a surprise that over 95% of “life on land” resides in soil, and that most of the energy for the world beneath our feet is derived from plant carbon. Living roots are the most energy-rich of these carbon sources. Other than the oceans and fossil fuel deposits, soils are the largest reservoirs of carbon on the planet, holding approximately two times the amount in the atmosphere and vegetation combined. The dark color of fertile soil comes from the presence of organic carbon compounds
Microbes in the vicinity of plant roots and microbes linked to plants via networks of beneficial fungi — increase the availability of the minerals and trace elements required to maintain the health and vitality of their plant hosts. Microbial activity also drives the process of aggregation, which enhances soil structural stability, aeration, infiltration, and water-holding capacity. All living things — above and below ground — benefit when the plant-microbe bridge is functioning effectively.
Soil restoration begins with photosynthesis. Imagine there was a process that could remove carbon dioxide from the atmosphere, replace it with life-giving oxygen, support a robust soil microbiome, regenerate topsoil, enhance the nutrient density of food, restore water balance to the landscape, and increase the profitability of agriculture. It’s called photosynthesis.
In the miracle of photosynthesis, which takes place in the chloroplasts of green leaves, carbon dioxide from the air and water from the soil are combined to capture light energy and transform it into biochemical energy in the form of simple sugars. These simple sugars are the building blocks of life. Plants transform sugar into a great diversity of other carbon compounds, including starches, proteins, organic acids, cellulose, lignin, waxes, and oils. Fruits, vegetables, nuts, seeds, and grains are packaged sunlight derived from photosynthesis. Significantly, many of the carbon compounds derived from the simple sugars formed during photosynthesis are also essential to the creation of well-structured topsoil. Without photosynthesis there would be no soil. Weathered rock minerals, yes … but no fertile topsoil.
Soil restoration is our ally in the fight against global warming. By capturing carbon and reversing desertification caused by severe drought, soil restoration enhances regional cooling, strengthens resilience against droughts and floods. As noted above, restoring soil ameliorates desertification, a factor that can destabilize already volatile regions. Take the unprecedented drought that precipitated civil unrest in Syria before the outbreak of civil war there. The drought was exacerbated by global warming just as were the wildfires in the western U.S. these past summers.
In a 2014 white paper, the Rodale Institute showed that regenerative organic farming could capture carbon dioxide in quantities exceeding global emissions. I was surprised to read this. The institute compared organic fields with chemical fields and found much more microbiological activity in the organic fields which led to greater carbon sequestration. In a Swiss study – comparing biodynamics with organic, there was even more microbiological activity using biodynamics methods. (The Rodale Institute supports research into organic farming. The institute was founded in 1947 by entrepreneur J.I. Rodale in Emmaus, Pennsylvania. When J.I. Rodale died in 1971, his son Robert purchased 333 acres and moved the farm to its current site in Kutztown, Pennsylvania.)
Sadly, many of today’s farming methods have severely compromised soil microbial communities, significantly reducing the amount of carbon transferred to and stabilized in soil. Over the last 150 years, many of the world’s prime agricultural soils have lost between 30% and 75% of their carbon, adding billions of tons of CO2 to the atmosphere. And over the last 70 years, the level of nutrients in almost every kind of food has diminished.
On the other hand, soil carbon can increase when farmers and gardeners maintain constant ground cover, add compost, increase microbe populations, encourage biological diversity, reduce the use of agricultural chemicals, and avoid tillage. So look no further than the ground beneath your feet for a healthy world.