ARS | Publication request: SPATIAL VARIATION OF ENERGY BALANCE AND CARBON DIOXIDE EXCHANGE IN CORN AND SOYBEAN FIELDS OF CENTRAL IOWA

Submitted to: ASA-CSSA-SSSA Annual Meeting Abstracts
Publication Type: Abstract
Publication Acceptance Date: November 4, 2004
Publication Date: November 4, 2004
Citation: Hatfield, J.L., Prueger, J.H., Kustas, W.P. 2004. Spatial variation of energy balance and carbon dioxide exchange in corn and soybean fields of central Iowa [CD-ROM]. ASA-CSSA-SSSA Annual Meeting Abstracts. Madison, Wisconsin.

Technical Abstract: Spatial variation in components of the energy balance has been assumed to vary with crop and landscape position; however, there are few measurements to actually document the amount of variation present. As part of a large energy balance experiment conducted in Central Iowa during 2002, sensible, latent, and CO2 fluxes along with net radiation and soil heat flux were measured over a 5,100 ha watershed in corn (Zea mays L.) and soybean (Glycine max. (L.) Merr.) fields. The largest variation among and within crops was found during the vegetative period when the crops were rapidly growing. Variation in sensible heat was largest for soybean canopies and greater variation in latent heat was observed among the corn canopies. The spatial patterns of sensible, latent, and CO2 fluxes were dependent upon growth stage and soil water availability. Understanding these patterns will help develop improved regional scale models of the energy balance components.