Carbon Dioxide Exchange in Maize and Soybeans

Andrew E. Suyker, Shashi B. Verma

Research output: Contribution to conferencePaperpeer-review


The gross primary productivity (GPP), and ecosystem respiration (R eco) of carbon dioxide was examined in irrigated maize and irrigated soybean fields grown in eastern Nebraska. In both fields, seasonal changes in GPP (during clear skies) closely followed a hyperbolic relationship with green LAI during the vegetative and early reproductive growth stages. The nighttime R eco displayed an exponential relationship with air temperature with Q 10 between 1.5 and 2.0 for a given range of green LAI. For constant air temperatures during the season, the nighttime R eco also showed a strong influence of the green LAI for both crops. The GPP of the maize ecosystem, integrated over the growing season, was substantially larger (1715 g C m -2) as compared to that of the soybean canopy (980 g C m -2) even though peak green LAI was comparable. The seasonally integrated ecosystem respiration however, was more comparable (about 1120 and 855 g C m -2 in the maize and soybean, respectively).

Original languageEnglish (US)
Number of pages1
StatePublished - 2004
Externally publishedYes
Event26th Conference on Agricultural and Forest Meteorology - Vancouver, BC, Canada
Duration: Aug 23 2004Aug 26 2004


Conference26th Conference on Agricultural and Forest Meteorology
CityVancouver, BC

ASJC Scopus subject areas

  • General Engineering


Dive into the research topics of 'Carbon Dioxide Exchange in Maize and Soybeans'. Together they form a unique fingerprint.

Cite this