2015 GSA Annual Meeting in Baltimore, Maryland, USA (1-4 November 2015)

Paper No. 210-26
Presentation Time: 9:00 AM-6:30 PM


FORTNER, Sarah K., Geology, Wittenberg University, Springfield, OH 45501 and BARTELL, Catherine, Department of Geology, Wittenberg University, PO Box 720, Springfield, OH 45501, bartellc@wittenberg.edu

Carbon is stored in soil from decaying material from once-living organisms such as plant and animal tissues and provides structure and nutrition to plants. Bioavailable nitrogen is important to plant health because it is essential for plant growth and stability. This study examines soil organic carbon (SOC) and summer nitrate availability at depths of 0 cm, 8 cm, 14 cm, and 22 cm at two land management types in The Antioch Farm in Yellow Springs, Ohio. Samples were collected in June 2014 and analyzed using loss on ignition and extraction and ion chromatography for SOC and nitrate respectively. Land management types examined include: 1) a plot of land that had been heavily disturbed and compacted by construction and then established as an annual agricultural plot in 2011 and 2) a permaculture garden known as the Food Forest. The sampled southern end of the annual agricultural plot was sub-soiled and tilled in 2011, when the farm was started, and is tilled as needed by a walk behind tiller. This plot has been heavily amended through compost and manure. Soil in the Food Forest has never been tilled at as far back as records are kept (10+ years). Management includes hand weeding and establishing new perennials that increase biodiversity and improve symbiotic plant relationships. At both sites, the greatest nutrient concentrations were found in the soil surface. However, heavy amendments promoted greater concentrations of SOC and nitrate in the annual garden at the surface of the annual garden. For example, SOC was more than twice as high at 10.2% and nitrate was three times higher at 30.6 mg/L. This soil also had as much as twice as much SOC as a no-till corn crop at another Ohio site. Results reflect the important role of compost and amendments to local-scale soil solutions.