Inter-Annual Carbon, Evapotranspiration and Sensible Heat Flux Dynamics of Old World Bluestem in the Southern Great Plains.

Declining water resources is a major threat for agriculture around the globe. In the Southern Great Plains of the US, depletion of the Ogallala Aquifer is causing a shift from conventional cropping systems such as cotton (Gossypium hirsutum) and corn (Zea maize) to more water efficient cropping and pasture systems. Old World bluestem (Bothriochloa bladhii) “WW-B. Dahl” is a C4 perennial bunch grass (that has been introduced successfully in the southern Great Plains in the early 1990s.).  It is a bunchgrass with an upright growth habit and has better drought tolerance and water use efficiency than conventional cropping systems in the Southern Great Plains. The popularity of Old world bluestem in the Southern Great Plains as a high biomass pasture grass makes it important to study its impact on carbon, evapotranspiration and energy balance of this region. An eddy covariance flux tower was installed in the middle of a 78 acre WW-B. Dahl field to measure carbon and energy fluxes.  Results from this study will be presented at this meeting.