HR: 0800h
AN: H51H-0867    [Abstracts]
TI: Recharge in Karst Shrublands of Central Texas: Monitoring Drip Rates in Shallow Caves
AU: * Bazan, R A
EM: bobbazan@tamu.edu
AF: Water Management and Hydrological Science - Texas A&M University, 2138 TAMU, College Station, TX 77843, United States
AU: Wilcox, B P
EM: bwilcox@tamu.edu
AF: Ecosystems Science and Management - Texas A&M University, 2138 TAMU, College Station, TX 77843, United States
AU: Munster, C L
EM: c-munster@tamu.edu
AF: Biological and Agricultural Engineering - Texas A&M University, 2117 TAMU, College Station, TX 77843, United States
AU: Owens, K
EM: keith.owens@okstate.edu
AF: Natural Resource Ecology and Management - Oklahoma State University, 008C Ag Hall, Stillwater, OK 74077, United States
AU: Shade, B
EM: bev@zaraenvironmental.com
AF: Private Contractor, 4811 Duval St., Austin, TX 78751, United States
AB: The exceedingly complex subsurface hydrology of karst landscapes presents formidable challenges to understanding recharge rates and the relationships between rainfall and recharge. In this study, we have established a network of drip collectors and monitoring stations in shallow caves in the Edwards Plateau to better understand the dynamics of recharge and eventually for determining the effect of woody plants on recharge rates. Understanding recharge rates has direct relevance for management of the Edwards Aquifer, which serves as the main source of fresh water for the city of San Antonio and surrounding communities, As population around San Antonio continues to grow so does the demand for water, in turn, a need to address the supply exists. We have instrumented two caves that lie within the Camp Bullis Training Facility north of San Antonio, Texas. Data collected at each site record precipitation on the surface and measure recharge inside the caves. Monitoring of natural rainfall events at these sites began in October 2004. To date, all monitoring and data collection has occurred with the juniper canopy in place. Results have shown that cave recharge is influenced by 1) rainfall intensity and duration, 2) antecedent soil moisture condition, 3) depth of soil, and 4) surface geology. We plan to remove the tree canopy in the summer of 2008 and continue monitoring cave recharge in response to natural and re-created rainfall events. Comparing data collected with and without juniper cover in place will allow us to determine if recharge may be increased by reducing tree cover.
DE: 1813 Eco-hydrology
SC: Hydrology [H]
MN: 2007 Fall Meeting