Date of Award

Winter 2017

Project Type


Program or Major

Natural Resources and Environmental Studies

Degree Name

Master of Science

First Advisor

Serita D Frey

Second Advisor

Gopal K Mulukutla

Third Advisor

William H McDowell


Soil moisture is an important component in the interaction of terrestrial and aquatic systems, as it may play a role in regulating streamflow and the delivery of nutrients from soils to streams. There are few studies that collect in situ soil moisture and stream discharge data simultaneously at the same location across different land uses at a fine enough temporal resolution to understand processes at sub-daily timescales. I examined the relationship between soil moisture and streamflow over varying timescales using concurrent, high temporal frequency (one hour) in situ measurements of soil volumetric water content and stream discharge at five headwater catchments with different land use characteristics. I found that soil moisture and streamflow appear to be coupled, and that antecedent moisture conditions and seasonal change in temperature and precipitation regulated this coupling. Furthermore, each site/land use had a different coupling relationship and the antecedent requirements to induce coupling differed by site. I also found that depth in the soil profile, timescale, and site specific characteristics all played a role in streamflow coupling. Simultaneous measurement of streamflow and soil moisture across different spatial and temporal scales is key to understanding the actual physical connectivity between terrestrial and aquatic systems. Strategic placement of in situ sensor networks will allow us to better understand the interactions among atmosphere, land, and water that couple soils and surface waters.