Soil Respiration in CRUI Land Use Project at Harvard Forest 1997

Soil properties and processes were evaluated on three types of colonial agricultural land-use - plowing, pasturing, and selective tree removal in a woodlot that ceased in the mid to late 1800s. Plowing, the most intensive type of agricultural disturbance, mixes soil to a depth of approximately 15cm, homogenizing the soil resources and likely reducing diversity in microenvironments. Removing trees and replacing them with grasses for pasture decreases the organic matter amount and types of inputs to the system, decreasing resource diversity. Woodlots, altered by selective and chronic tree removal, would have more limited decreases in resources and microenvironments. This study examined soil surface (at 10cm above the soil surface) CO2 concentrations and soil respiration at the land use sites. Soil respiration and surface CO2 concentrations were highest in the woodlot sites and lowest in the formerly plowed sites.