HR: 1330h
AN: B52A-1027    [PDF]
TI: Rainfall Simulation Study of a Hillslope Covered in Dense Juniper
AU: * Porter, S
EM: s-porter@tamu.edu
AF: Department of Biological and Agricultural Engineering, 201 Scoates Hall MS 2117, College Station, TX 77843 United States
AU: Munster, C
EM: c-munster@tamu.edu
AF: Department of Biological and Agricultural Engineering, 201 Scoates Hall MS 2117, College Station, TX 77843 United States
AU: Wilcox, B
EM: bwilcox@tamu.edu
AF: Department of Rangeland Ecology and Management, 225 Animal Industries MS 2126, College Station, TX 77843 United States
AU: Owens, K
EM: m-owens@tamu.edu
AF: Texas Agricultural Experiment Station, 1618 Garner Field Road, Uvalde, TX 78801 United States
AU: Mohanty, B
EM: bmohanty@tamu.edu
AF: Department of Biological and Agricultural Engineering, 201 Scoates Hall MS 2117, College Station, TX 77843 United States
AB: Over the last hundred years, the semi-arid region of Southwestern United States has undergone a considerable change in landscape. The region that was once primarily covered by native grass has been invaded with brushy species, such as ash juniper (cedar) and mesquite. This brush encroachment has resulted in a major effect on the hydrologic cycle. With new brush species dominating the once grass-covered landscape, new trees are believed to transpire more water on an annual basis. In addition, the tree canopy traps more water through interception, which makes the water more susceptible to evaporation. It is thought that these processes limit water infiltration into the saturated zone, which results in less groundwater recharge. An alternative belief is that these new trees promote infiltration and groundwater recharge by creating preferential flow paths via extensive deep roots, which channel water through the vadose zone to the groundwater. A current research project examines the hydrologic interactions of water and brush as a means of quantifying the amount of available water for recharge to the aquifer. This project on the Texas Parks \& Wildlife Department's Honey Creek State Natural Area lies within the drainage area of the Edwards Aquifer. By using the Texas A\&M above-canopy rainfall simulator, rainfall events were applied to a 7 m by 14 m plot dominated by cedar species. The research plot was instrumented to record surface runoff, lateral subsurface flow, soil moisture, canopy interception, juniper transpiration, stem flow, and through fall. To monitor lateral subsurface flow, a 2 meter deep trench was excavated at the base of the plot. Initial rainfall simulation results will be presented.
DE: 0600 ELECTROMAGNETICS
DE: 1884 Water supply
SC: Biogeosciences [B]
MN: 2003 Fall Meeting