The Critical Zone Lab (CZL) at Virginia Tech focuses on quantifying and scaling interactions between water, soil, and plant communities. This includes a combination of field work, laboratory analysis, and development of modeling frameworks. We foster active collaboration across disciplines, working on topics which span ecology, engineering, agriculture, and urban systems.
In the CZL we utilize three main approaches: concepts derived from fundamental principles, observations employing novel techniques, and synthesis combining analytical quantification with numerical experiments.
Current and Future Research Projects

Linking Dynamic Soil Physical Properties with Hydrological Processes
Infiltration studies
Overland flow thresholds
Infiltration studies
Overland flow thresholds
- Urban hydrology
- Stable water isotope fate and transport
- Post-mining soil reclamation and recovery
- Soil-water vapor interactions

Management Effects on Soil Health
Demonstrate and quantify the effect of management practices on soil physical properties
Link biological indicators of soil "health" with physical soil characteristics
Quantify nutrient cycling and loss under these three management practices
Develop new methods to measure soil structure and soil respiration/GHG emissions
Evaluate management strategies that can enhance agro-ecological functioning
Demonstrate for farmers the effects of different management practices on soil properties
Demonstrate and quantify the effect of management practices on soil physical properties
Link biological indicators of soil "health" with physical soil characteristics
Quantify nutrient cycling and loss under these three management practices
Develop new methods to measure soil structure and soil respiration/GHG emissions
Evaluate management strategies that can enhance agro-ecological functioning
Demonstrate for farmers the effects of different management practices on soil properties

Preferential Flow through Structural Pathways
- Characterize structural pathways caused by plants and soil aggregation
- Describe preferential flow using parsimonious models
- Predict nutrient and pollutant transport
- Develop new soil parameters to use in infiltration and runoff modeling
- Create numerical models to better understand processes

Hydrological Processes in Clayey Shrink-Swell Soils
Quantify time-dependence of swelling
Identify and understand non-linear threshold behaviors in runoff and infiltration
Measure and model changing hydraulic conductivity of soil matrix due to swelling and shrinking
Develop scaling relationships for hydrologic processes in shrink-swell clay soils
Develop models to quantify and predict soil shrinkage and swelling properties
Quantify time-dependence of swelling
Identify and understand non-linear threshold behaviors in runoff and infiltration
Measure and model changing hydraulic conductivity of soil matrix due to swelling and shrinking
Develop scaling relationships for hydrologic processes in shrink-swell clay soils
Develop models to quantify and predict soil shrinkage and swelling properties

Fire Effects on Hydrology and Soils
Incidence and persistence of soil water repellency after fire
Wildfire effects on rainfall-runoff partitioning
Water quality and quantity before and after prescribed fire
Fire effects on soil aggregate stability
Incidence and persistence of soil water repellency after fire
Wildfire effects on rainfall-runoff partitioning
Water quality and quantity before and after prescribed fire
Fire effects on soil aggregate stability

Development of Novel Instruments and Methods
Develop new "resonating" raingauge
Innovate methods to consistently quantify soil aggregate stability
Design new device to measure plot-scale runoff
Incorporate accelerometers into monitoring of environmental processes
Apply Arduino-based sensors for increasing spatial and temporal resolution in measurements
Develop new "resonating" raingauge
Innovate methods to consistently quantify soil aggregate stability
Design new device to measure plot-scale runoff
Incorporate accelerometers into monitoring of environmental processes
Apply Arduino-based sensors for increasing spatial and temporal resolution in measurements