Intellectual Merit: NSF supported researcher Roger Bales and colleagues have developed a prototype instrument cluster for the study of mountain hydrology, biogeochemistry and ecology. Instrument-cluster measurements and resulting data enable research to understand basin-scale water cycles, how those cycles respond to climate and land-cover perturbations, water-biogeochemical cycle links, vegetation-water-nutrient cycle feedbacks, and feedbacks between water, geochemical weathering and landscape evolution. Data from strategically placed instrument clusters, designed to compliment satellite remote sensing information, are also being used tin advanced hydrologic modeling tools, influence quantitative hydrologic forecasting and provide insight for infrastructure planning.

Broader Impacts: Development of a water-balance instrument cluster in the Southern Sierra Nevada provides data and information that enhances the science of multiple individuals and research groups. This infrastructure provides for the design and evaluation of a much-needed prototype, that is being replicated across the landscape as the science community works to build large-scale environmental observatories. It also provides a template for design of new information systems for water and forest management, and is being adapted for operational use.

Research objectives:− Develop measurement strategies for accurate estimation

of snowpack amount, soil moisture, snowmelt and partitioning of snowmelt/rain into runoff versus infiltration and evapotranspiration (ET) in mountain basins.

− Demonstrate the applicability of an integrated satellite and ground-based measurement strategy through deployment of a prototype system employing emerging technologies.

− Provide measurements needed to accurately estimate mountain water fluxes, reservoirs and related biogeochemical cycles, in a representative southern Sierra Nevada, mountain basin.

Conceptual design and deployment of instrument clusters in a mountain basin.

View from eddy-covariance flux tower, a central component of the instrument cluster

Cluster component instrumentation includes snow depth, radiation, sap flow and soil moisture sensors.

Development of water-balance instrument cluster for mountain hydrology, biogeochemistry and ecology

Location: The site for the instrument cluster is in the Kings River Experimental Watersheds (KREW), part of the Sierra National Forest (37.0665oN, 119.1940oW, 1,750-2,000 m elevation). KREW is a watershed-level, integrated ecosystem project for long-term research on headwater streams in California’s Southern Sierra Nevada. KREW is also the site of the NSF-supported Southern Sierra Nevada Critical Zone Observatory (EAR-0725097). Spatially distributed, high-frequency measurements of water and geochemical processes across multiple nested catchments are the foundation for research in the Southern Sierra CZO.

Principal investigator: Roger Bales, Professor, University of California Merced, rbales@ucmerced.eduFor more information: http://snri.ucmerced.edu/CZOCredit: Dr. Roger Bales, permission granted Award: EAR-0619947