ORGANIC CARBON CONTENT OF SOIL AT A NO-TILL FARM IN THE FINGER LAKES REGION, NEW YORK

Organic carbon content is an important indicator of soil health and overall possible crop yield because it can help to reduce water runoff and increase water retention, aggregation, and cation exchange capacity. It has been shown that no-till farming practices can increase the organic carbon content of the soil in addition to reducing erosion. The goal of this study was to determine the organic carbon content of the soil at a no-till farm under different crop rotations. The selected farm is located between Seneca and Cayuga lakes in Lodi, NY. The farm has been practicing no-till land management for three decades. We selected five sites on the farm: two wheat and two corn fields, and a forested area. The forest has not been harvested for over 100 years, it represents a second-growth forest in the area, and serves as a control in our study. At each site, we collected three intact core samples and a composite sample of the top 10 cm. We separated the core samples into 0-5, 5-10, and 10+ cm sections. The soil samples were dried and then sieved to separate the less than 2 mm fraction for further analysis. Electrical conductivity, pH, color, and texture were determined using standard methods. Soil organic matter content was estimated based on loss on ignition using a muffle furnace, then organic carbon content was calculated using the assumption that organic matter contains about 58% carbon. The forest soil is the most acidic (pH of 5.5) and the croplands’ pH is about one pH unit higher. As expected, the top 5 cm layer of the soil has the highest carbon content in all samples and it decreases by depth. The forest soil also has the highest carbon content overall (5.3%), the second highest is in the corn field (4.8%), and the lowest is in the wheat field (4.2%). These values indicate that no-till farming has a positive impact on the carbon recovery of managed soil, but it takes a long time to reach the natural carbon values of the landscape.