| |
Communication at the NABS Annual meeting, Keystone, 2000
(169) ESTIMATING WATER DEPLETION FOR A RIVER REACH IN A REGION WITH A SEMI-ARID
CLIMATE.
C.N. Dahm, M.C. Molles, Jr., J.R. Cleverly, J.R. Thibault, and C.S. Crawford. Department of Biology, University of New Mexico, Albuquerque, NM 87131-1091, USA
Nowhere are anthropogenic impacts on river and riparian ecosystems greater than in arid and semi-arid regions of the world. Water is the lifeblood of these regions that constitute about 33% of the land surface worldwide. Ever increasing human demand for fresh water in these regions leads to the inevitable conflict between the use of water for human needs and the requirements for water by native ecosystems. A growing concern about effectively managing the needs for water by humans and river/riparian ecosystems has generated a careful recent reexamination of the water budget of the Middle Rio Grande (~320 km) in New Mexico, USA. Highlights of this water budget based on averages for 1972-1997 will be presented as an example of annual variability, measurement uncertainty, and conflicting demands on water resources in a semi-arid region. The major sources of average annual depletion within the Middle Rio Grande in order of estimated importance are open-water evaporation (~32%), riparian plant transpiration (~24%), irrigated agriculture (~20%), urban consumption (~13%), and net aquifer recharge (~11%). Many of these depletions vary substantially year-to-year and estimates of many of these terms come with large measurement uncertainties. The budget, the variability, and the uncertainty will be presented and discussed.
Presented at 4:45 PM on Tuesday, May 30, 2000 in Hydrologic Alterations
|
|
