Carbon Dioxide Evolution from the Floor of an Oak‐Hickory Forest

Carbon dioxide evolution from the floor of an oak‐hickory ( Quercus sp.) ( Carya sp.) forest was studied. The influence of soil temperature, soil moisture, and position on a west‐facing slope was evaluated on a seasonal basis. Highest evolution rates were observed during the summer and declined in the order of fall, spring, and winter. Maximum summer rates were 1.20 g/m 2 per hour while maximum winter rates were 0.18 g/m 2 per hour. Temperature was found to have its greatest limiting effect during the winter and spring while moisture was most limiting during the fall. Release of CO 2 at the lower slope position was 20% greater on a mean annual basis than at the middle and upper slope positions. Most of the CO 2 evolved from the forest floor is considered to be contributed by root respiration and associated microorganisms.