Scott Mackay

In this work a novel integrated hydrodynamic model was developed to aid in understanding the environmental flows needed to conserve riparian cottonwoods. In semi-arid regions riparian woodlands depend heavily on stream discharge to provide lateral water inputs to the floodplain to sustain trees through droughts. Climate dynamics are increasing the likelihood of reduced snow accumulation that sustains these river systems through dry periods, and future warm droughts coupled with increased water diversion risk substantial woodland loss. The model presented in this work, ParFlow-TREES, combines a three-dimensional groundwater hydrology model with a plant physiology model that simulates water stress using measures such as percent loss of hydraulic conductance (PLK). The graphic above depicts increasing PLK with distance from the stream and reduced PLK with increasing stream discharge. The work was published in Water Resources Research (Tai et al., 2018) and featured on the cover of the July 2018 issue of the journal.

Tai, X., D.S. Mackay, J.S. Sperry, P. Brooks, W.R.L. Anderegg, L.B. Flanagan, S.B. Rood, and C. Hopkinson. 2018. Distributed plant hydraulic and hydrological modeling to understand the susceptibility of riparian woodland trees to drought-induced mortality. Water Resources Research, 54, 4901-4915, doi:10.1002/2018WR022801.