U.S. Department of Agriculture: Agricultural Research Service, Lincoln, Nebraska


Date of this Version



Published in Functional Ecology 2008, 22, 163–171.


A series of weighing lysimeters in which tallgrass prairie species had been planted were exposed to a subambient to elevated gradient in CO2 in a field chamber. Lysimeters with intact monoliths of three soil types were represented along the CO2 gradient. We used regression analysis to determine how CO2 effects on evapotranspiration per unit of soil surface area (ETsoil) and per unit of leaf area (ETla) depended on variation in leaf area index (LAI) and diurnal changes in environmental variables during the initial 6 weeks of CO2 treatment.