The Kings River Experimental Watersheds: resolving processes in Sierra Nevada headwaters since 2002

The Kings River Experimental Watersheds were established in 2002 to expand our knowledge of catchment physical, chemical, and biological processes in Sierra Nevada headwater forests and the implications of forest management activities on these processes. Two elevation strata were selected and four catchments in each elevation range were identified and instrumented for continuous measurements of meteorology, streamflow, atmospheric and stream chemistry, suspended sediment concentration, turbidity, and bedload sediment delivery. Soil chemical and physical properties, channel morphology, hillslope sediment production, vegetation, and aquatic organisms were systematically sampled before and after the first treatments of thinning and prescribed burning, which were implemented between 2012 and 2016. Post-treatment data collection continues at a reduced scope today as we explore opportunities for the second round of possible treatments. The investment in critical research infrastructure and long-term baseline data collection has been instrumental in building partnerships with downstream stakeholders, non-governmental organizations, academic researchers, and national research programs including the Southern Sierra Critical Zone Observatory and the National Ecological Observatory Network. Contributions to date include fundamental understanding of magnitude and variability of nutrient deposition; carbon, nutrient, and major ion dynamics; macroinvertebrate populations; vegetation composition and structure; and streamflow responses to precipitation in the two elevation bands. Data from the experimental watersheds also support calibration and validation of diverse hydrologic models and water resources planning. Key findings will be presented.