Thursday, 25 May 2006: 2:00 PM
Rousseau Suite (Catamaran Resort Hotel)
Fluxes of CO2, water vapor and energy are being measured year-round in maize-soybean agroecosystems in eastern Nebraska employing tower eddy covariance instrumentation. CO2 flux data are used to calculate ecosystem respiration at two study sites: rainfed maize-soybean rotation and irrigated maize-soybean rotation. Ecosystem respiration from the maize and soybean crops varied from about 800 to 1200 g C m-2 annually. A detailed discussion of the magnitudes of ecosystem respiration in these cropping systems during the growing season and non-growing season periods will be presented. Results will be compared with data from other ecosystems. An examination of key biophysical controlling factors will also be presented.
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