Seasonal Variations in Evaporation for Three Plant Communities in the Great Basin using Eddy Covariance Measurements
Location
Space Dynamics Laboratory
Event Website
http://water.usu.edu/
Start Date
3-25-2004 12:00 PM
End Date
3-25-2004 12:05 PM
Description
Eddy covariance measurements were used to determine seasonal changes of water vapor flux in juniper (Juniperus osteosperma), sagebrush (Artemisia tridentata) and crested wheatgrass (Agropyron desertorum) communities in the Great Basin over the entire growing seasons of 2002 and 2003. In both years there was variation in water vapor fluxes between the sites and across seasons. Sagebrush and juniper were able to continue to use water over the entire growing season, while crested wheatgrass became senescent and stopped transpiration early in the summer. Total LE values for the spring period of 2002 were very similar at all sites. Precipitation was lower during the spring of 2003 which resulted in significantly higher water fluxes from juniper and sage compared to crested wheatgrass, presumably due to better access to deep water by sagebrush and juniper compared to crested wheat grass. Evapo-transpiration fluxes decreased during the summer at all sites. However, the juniper and sagebrush communities remained physiologically active throughout the summer and into fall while crested wheatgrass senesced. The water vapor fluxes responded to intermittent rain events in the summer. The length of the responses was longer for juniper and sage, since they were physiologically active. Juniper and sage were able to respond to rain events in the fall. Although the general seasonal changes of evapo-transpiration showed some similarity at each site, the timing and details of water use varied among species.
Seasonal Variations in Evaporation for Three Plant Communities in the Great Basin using Eddy Covariance Measurements
Space Dynamics Laboratory
Eddy covariance measurements were used to determine seasonal changes of water vapor flux in juniper (Juniperus osteosperma), sagebrush (Artemisia tridentata) and crested wheatgrass (Agropyron desertorum) communities in the Great Basin over the entire growing seasons of 2002 and 2003. In both years there was variation in water vapor fluxes between the sites and across seasons. Sagebrush and juniper were able to continue to use water over the entire growing season, while crested wheatgrass became senescent and stopped transpiration early in the summer. Total LE values for the spring period of 2002 were very similar at all sites. Precipitation was lower during the spring of 2003 which resulted in significantly higher water fluxes from juniper and sage compared to crested wheatgrass, presumably due to better access to deep water by sagebrush and juniper compared to crested wheat grass. Evapo-transpiration fluxes decreased during the summer at all sites. However, the juniper and sagebrush communities remained physiologically active throughout the summer and into fall while crested wheatgrass senesced. The water vapor fluxes responded to intermittent rain events in the summer. The length of the responses was longer for juniper and sage, since they were physiologically active. Juniper and sage were able to respond to rain events in the fall. Although the general seasonal changes of evapo-transpiration showed some similarity at each site, the timing and details of water use varied among species.
https://digitalcommons.usu.edu/runoff/2004/AllPosters/2