Converting Chaparral to Grass to Increase Streamflow
Affiliation
Rocky Mountain Forest and Range Experiment StationIssue Date
1972-05-06Keywords
Hydrology -- Arizona.Water resources development -- Arizona.
Hydrology -- Southwestern states.
Water resources development -- Southwestern states.
Chaparral
Grasses
Streamflow
Water supply
Water harvesting
Surface waters
Watershed management
Forest management
Rainfall-runoff relationships
Treatments
Arizona
Arid lands
Metadata
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Copyright ©, where appropriate, is held by the author.Collection Information
This article is part of the Hydrology and Water Resources in Arizona and the Southwest collections. Digital access to this material is made possible by the Arizona-Nevada Academy of Science and the University of Arizona Libraries. For more information about items in this collection, contact anashydrology@gmail.com.Publisher
Arizona-Nevada Academy of ScienceAbstract
Chaparral covers 4 million acres in Arizona. There is interest in determining how much these lands contribute to surface water supply, and how this contribution could be changed by conversion of chaparral cover to grass or grass forb. Results from treatment in the Whitespar watersheds are interpreted. Live oak and true mountain mahogany dominate the study area, which averages 22.7 inches of annual precipitation. Whitespar B watershed was converted to grasses in 1967, and litter was not disturbed. The 246 acre watershed produced more streamflow than the untreated, 303-acre control which tended to remain intermittent. Prior to treatment, streamflow in both watersheds was quite well synchronized. Watershed b has since had continual flow. Winter flows contribute about 77 percent of the increased streamflow volume. The degree of effect is still under study, but a new rainfall-runoff relationship for the treated watershed is necessitated.ISSN
0272-6106Related items
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