Initial response of evapotranspiration from tallgrass prairie vegetation to CO2 at subambient to elevated concentrations

Authors

H. W. Polley, USDA-ARS Grassland, Soil and Water Research LaboratoryFollow
H. B. Johnson, USDA-ARS Grassland, Soil and Water Research Laboratory
P. A. Fay, USDA-ARS Grassland, Soil and Water Research LaboratoryFollow
J. Sanabria, Texas Agricultural Experiment Station

Date of this Version

2008

Comments

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

Abstract

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 (ET_soil) and per unit of leaf area (ET_la) depended on variation in leaf area index (LAI) and diurnal changes in environmental variables during the initial 6 weeks of CO₂ treatment.