JoAnne Skelly: Backyard carbon sequestration
Atmospheric carbon dioxide (CO2) is the most significant greenhouse gas and it plays a major role in global warming and climate change. Organic carbon in the soil and plant biomass (plants and their debris) originates from atmospheric CO2. All plants use CO2 in the process of photosynthesis — utilizing it plus the energy from the sun, and water to produce the sugars needed to “feed” the plant. The photosynthetic process releases oxygen and carbon. As gardeners, we can help in carbon capture and storage (sequestration) and reduce CO2 emissions by our landscaping and gardening techniques. Actually, we gardeners act as carbon capturers without intending to every time we plant, particularly when planting trees. In general, trees store more carbon than grasslands, which store more than crops.
Although most of us have small properties, our actions can contribute to reducing the buildup of greenhouse gases. We can join our efforts together to make a difference. We can use organic rather than synthetic fertilizers, since organic ones enhance soil health. When we improve our soils, we reduce CO2. Soils hold more organic carbon than the amount in vegetation and the atmosphere. Putting organic matter (biomass) into the soil, particularly in the form of humus, helps sequester carbon and reduces the likelihood of it being released and converting back to CO2. Protecting the soil from the sun with mulch and cover crops conserves soil moisture and also captures carbon. Encouraging deep roots stabilizes soils and takes carbon deeper into the soil where it’s less likely to be released. Leaving grass clippings on the lawn sequesters carbon.
We can reduce our CO2 emission production by using equipment that’s either more fuel-efficient or that uses less to no fuel in the first place, such as an electric or push lawn mower. Think of how many gas-powered mowers, weed trimmers, edgers and blowers are used every day in home landscapes, each producing greenhouse gases. Using no-till soil and garden preparation methods not only avoids a roto tiller’s emissions, it also disturbs the soil less so that carbon stored in the soil isn’t released into the atmosphere.
Our actions can slow the build-up of CO2 in the atmosphere.
“For deep carbon sequestration, the basic requirements are: help plants maximize photosynthesis and tend the soil biology. Minimize plowing or tilling and digging. Grow multi-species polycultures. Don’t leave soil bare for extended periods. Don’t use pesticides or synthetic fertilizer,” from http://www.ecologicalgardening.net.
JoAnne Skelly is Associate Professor & Extension Educator, Emerita at University of Nevada Cooperative Extension. She can be reached at firstname.lastname@example.org.