Critical Zone Measurements: Development of Novel Experimental Deployments to Further Our Understanding of Hydrological Processes

Session: Advancing Science through Long-Term Monitoring, Observation, and Experimentation in Catchment, Critical Zone, and Ecosystem Studies


Brandon Forsythe(1) , Jeremy Harper(1) , Susan Brantley(2) , John M Regan(3) , Caitlin Anne Hodges(4) , Jason P Kaye(5) and Andrew Nyblade(6) , (1)Pennsylvania State University Main Campus, University Park, PA, United States, (2)Pennsylvania State University, Earth and Environmental Systems Institute, University Park, PA, United States, (3)Pennsylvania State University, Environmental Engineering, University Park, PA, United States, (4)University of Georgia, Athens, GA, United States, (5)Department of Ecosystem Science and Management, State College, PA, United States, (6)Pennsylvania State University Main Campus, Department of Geosciences, University Park, PA, United States

Abstract Text:

Since 2013 Susquehanna Shale Hills Critical Zone Observatory (SSHCZO) has been monitoring using a Ground Hydrological Observation System (GroundHOG) design consisting of various sensor types in the Shavers Creek watershed in central Pennsylvania. The GroundHOG design was established to study interactions between hydrological systems (surface and groundwater), soils, and ecosystems along catenas. We currently have three GroundHOG sites with differing land uses and geology: one located in a pristine shale watershed, another in a pristine sandstone watershed, and the third in an agricultural setting with mixed lithology. Each catena has three pits set up to compare hill slope position and one additional pit to compare north versus south aspect. Each pit is equipped with both automated and manual sensors that measure soil moisture and soil gas at varying depths. The GroundHOG deployment is accompanied by precipitation gauges, surface water monitoring gauges, and groundwater monitoring wells at all sites. In 2019 we built on the shale site to include weekly electrical resistivity measurements and seismometry near the GroundHOG. Specifically, we designed and installed an innovative chronoamperometric system that can respond to real-time redox reactions that change in response to changes in soil moisture, temperature, and saturation. These experimental sensors are co-located with the GroundHOG sites where soil gas measurements take place and can be coupled to understand the connection of hydrological processes to microbial communities. This presentation will emphasize the design of the GroundHOG and how the new measurements are made and compared in the shale GroundHOG site.