Large Scale Carbon Capture Farming to Rebuild Soils
USGS, California and UC Davis begin large-scale Delta “carbon farm” Project will study best ways to capture atmospheric CO2, reverse island subsidence
The U.S. Geological Survey (USGS), the California Department of Water Resources (DWR) and the University of California, Davis plan to make it happen.
DWR has awarded USGS and UC Davis a three-year, $12.3 million research grant to take the concept of carbon-capture farming to full-scale in a scientifically and environmentally sound way.
Long-standing farming practices in the Delta expose fragile peat soils to wind, rain and cultivation, emit carbon dioxide (CO2) and cause land subsidence. To capture or contain the carbon, farmers would “grow” wetlands. In doing so, they would begin to rebuild the Delta’s unique peat soils, take CO2 out of the atmosphere, ease pressure on the Delta’s aging levees and infuse the region with new economic potential.
Carbon-capture farming works as CO2 is taken out of the air by plants such as tules and cattails. As the plants die and decompose, they create new peat soil, building the land surface over time.
Construction on the new wetlands, covering up to 400 acres on Twitchell Island, is scheduled to start in the spring of 2009.
Throughout the Delta, oxidation of the soils from farming practices has resulted in land-surface subsidence – a steady loss of elevation. As a result, most of the farmed Delta islands are more than 20 feet below the surrounding waterways and are permanently protected by levees.
The falling land surface threatens the stability of the region’s levees, which in turn protect the Delta’s rich agricultural lands and the conveyance of much of California’s water supplies. Water flowing through the Delta’s levee-protected farmland provides fresh water to more than 25 million Californians and millions of acres of farmland in the Central Valley.