ARS | Publication request: Hydrologic Research in a Pinyon and Juniper Encroached Watershed

Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: March 1, 2012
Publication Date: N/A

Technical Abstract: Pinyon and Juniper (P-J) woodlands have been expanding into areas formerly dominated by sagebrush steppe vegetation. This can produce changes in understory vegetation, fire regimes, erosion potential and hydrology. Thereby, treatments to reduce the cover of P-J are expected to have effects on these same variables, although these responses, particularly the hydrologic responses, can be difficult and/or time consuming to measure. Porter Canyon was a unique opportunity for agencies, university researchers and private landowners to work together to understand the effects of P-J expansion and treatment techniques on watershed hydrology, plant water-use, erosion potential and how these processes interact with vegetation community composition and structure. The goal at Porter Canyon is to have a fully instrumented watershed to measure the effect of cutting treatments on hydrologic and vegetation responses. The watershed is instrumented with vegetation transects to monitor changes in plant community, sapflux sensors to measure tree water use, soil moisture probes, NRCS scan weather station, a network of groundwater monitoring pressure transducers, spring boxes and detailed vegetation transects. Additionally, we have process-based experimental data. Results will be presented on: the amount of rainfall redistribution that occurs due to the presence of pinyon and juniper canopy area; the source and amount of water used by pinyon and juniper trees in both meadow and upland habitats during the summer growing season; and the effects of a specific cutting treatment on soil sediment production within two levels of understory vegetation cover.