ABSTRACT
To supplement water supplies, there has been considerable interest in using vegetation management (brush control) to increase stream flow and water yields (runoff þ deep percolation) from watersheds. One option on rangelands[1,2] is to replace deep-rooted woody brush species, which may intercept a substantial amount of precipitation and have high whole-plant transpiration rates due to high leaf areas, with shallow-rooted herbaceous vegetation that usually intercepts less precipitation and has less leaf area. The amount of increased stream flow and/or water yield, if any, on treated watersheds depends on several factors, including the pre-and post-treatment vegetation types or land use,[3] treatment method or soil,[4]
climate,[5] and time since treatment imposition.[6]
Wilcox[7] presents a perspective on the mechanisms of how brush clearing could affect streamflow. Several field and modeling studies in Texas have shown water yield increases associated with brush removal (Table 1). Based, in part, on these studies, a study was conducted to use a hydrologic simulation model to evaluate changes in stream flow and water yield associated with brush removal on several watersheds.[11] This report uses results from that work to present a case study of how brush clearing can influence rangeland water yield.
CASE STUDY
