The Salmonid and The Subsurface: The Importance of Rock Type for Understanding and Sustaining Stream Ecosystems

How does the structure of the critical zone - especially below shallow soils and into saprolite and weathered rock - control water storage and release to California forests and streams? In this talk, I will address this question with a synthesis of observational and modeling results from three intensively studied California catchments. Findings reveal bottom-up, lithologic controls on weathering profiles, subsurface water storage capacity, and summer baseflow drainage from the critical zone. Results highlight how, in addition to plant physiology and climate, the subsurface is a key regulator of ecosystem productivity, stream temperature, water availability, and forest response to drought.

Speaker: David Dralle, CSU Sacramento