HR: 14:25h
AN: B53B-04    [Abstracts]
TI: Pecos River Ecosystem Project: What are the Hydrologic Effects of Large-Scale Saltcedar Control?
AU: * McDonald, A K
EM: akmcdonald@ag.tamuedu
AF: Texas A&M University, MS 2126, College Station, TX 77843 United States
AU: Sheng, Z
EM: ZSheng@ag.tamu.edu
AF: Texas Agricultural Experiment Station, 1380 A&M Circle, El Paso, TX 79927-5020 United States
AU: Wilcox, B P
EM: BPWilcox@ag.tamu.edu
AF: Texas A&M University, MS 2126, College Station, TX 77843 United States
AU: Hart, C R
EM: CHart@ag.tamu.edu
AF: Texas Cooperative Extension, P.O. Box 1298, Fort Stockton, TX 79735-1298 United States
AB: Control of saltcedar ( Tamarix spp.) to reduce evapotranspiration (ET) and provide additional streamflow is not a new concept. However, previous studies failed to attribute a measurable increase in streamflow to a reduction in saltcedar. Why? Based on the water budget paradigm, a reduction in output (ET) generates an increase in another component of the water budget. However, it may be too simplistic to assume that phreatophyte control will increase streamflow. Does vegetation management induce a measurable change to the water budget? At what scale can we expect to measure this difference? The answers to these questions come by understanding hydrologic processes. In 2000 a saltcedar control program was implemented to improve irrigation delivery efficiency along the Upper Pecos River in Texas. Since then, saltcedar along 270 miles has been treated. A monitoring well network was established at two sites to estimate changes in water budgets of one treated and one untreated segment. Analysis of hourly water level data revealed reduced water loss (ET) along the treated segment. Although differences in water budget can be measured at these points, can those differences be detected at a larger scale? This study aims at gaining a better understanding of the interaction between the river and the shallow aquifer through inflow-outflow measurements and analysis of subsurface flow using monitored water levels. It is anticipated that the predicted response of the system to different management options can be determined.
DE: 0481 Restoration
DE: 0744 Rivers (0483, 1856)
SC: Biogeosciences [B]
MN: Fall Meeting 2005