Dr. Ryan Stewart

School of Plant and Environmental Sciences

Dr. Stewart received his bachelor’s degree in mechanical engineering from California Polytechnic State University, and a master’s degree and doctoral degree in water resource engineering Oregon State University. His research 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.
His Critical Zone Research Lab fosters active collaboration across disciplines, working on topics that span ecology, engineering, agriculture, and urban systems. The lab utilizes three main approaches: concepts derived from fundamental principles, observations employing novel techniques, and synthesis combining analytical quantification with numerical experiments.


Lab Website


Recent Relevant Publications

Stewart, R. D., Z. Liu, D. E. Rupp, C. W. Higgins and J. S. Selker. 2015. A new instrument to measure plot-scale runoff. Geoscientific Instrumentation, Methods and Data Systems. 4: 57-64. doi:10.5194/gi-4-57-2015.

Stewart, R. D., D. Moreno, and J. S. Selker. 2014. Quantification and scaling of infiltration from a constructed infiltration wetland. Journal of Hydrologic Engineering. 04015007. doi: 10.1061/(ASCE)HE.1943-5584.0001164.

Stewart, R. D., M. R. Abou Najm, D. E. Rupp, J. W. Lane, H. C. Uribe, J. L. Arumí, and J. S. Selker. 2015. Hillslope runoff thresholds in shrink-swell clay soils. Hydrological Processes. 29(4): 557-571. doi: 10.1002/hyp.10165.

Stewart, R. D., M. R. Abou Najm, D. E. Rupp, and J. S. Selker. 2014. Non-destructive quantification of macropore volume using shear-thinning fluid. Soil Science Society of America Journal. doi: 10.2136/sssaj2013.08.0346.

Uribe, H. C., D. E. Rupp, J. L. Arumí, R. D. Stewart, and J. S. Selker. 2014. Assessment of current and potential yield of hand-dug wells in a semi-arid zone in south-central Chile using an analytical methodology. Chilean Journal of Agricultural Research. doi:10.4067/S0718.

Petrides, A. C., R. D. Stewart, R. Bower, R. Henry, and R. H. Cuenca. 2014. Scaling recharge rates from pilot projects of managed artificial aquifer recharge. Journal of Hydrologic Engineering.

Stewart, R. D., D. E. Rupp, M. R. Abou Najm, and J. S. Selker. 2013. Modeling effect of initial soil moisture on sorptivity and infiltration. Water Resources Research. DOI: 10.1002/wrcr.20508.

Stewart, R. D., R. W. Hut, D. E. Rupp, H. Gupta, and J. S. Selker. 2012. A resonating rainfall and evaporation recorder. Water Resources Research. 48(8):W08601. DOI: 10.1029/2011WR011529.

Stewart, R. D., M. R. Abou Najm, D. E. Rupp, and J. S. Selker. 2012. An image-based method for determining bulk density and the soil shrinkage curve. Soil Science Society of America Journal. 76(4):1217-1221. DOI:10.2136/sssaj2011.0276n.

Stewart, R. D., M. R. Abou Najm, D. E. Rupp, and J. S. Selker. 2012. Measurement tool for dynamics of soil cracks. Vadose Zone Journal. 11(2). DOI:10.2136/vzj2011.0048