Modeling Capillary Rise in Clinoptilolite Zeolite and Riparian Soils to Sustain Vegetation in Water-Scarce Areas

Abstract

Clinoptilolite zeolite (CZ) is being considered as a wicking material for revegetation of riparian regions in arid environments where depth to groundwater is less than 3 m. Simulation of water fluxes and water contents in boreholes filled with CZ and in situ unamended riparian soil (RS) for the purpose of riparian revegetation was modeled using Hydrus-1D and compared to water content measurements. A review of the literature shows that Hydrus-1D model has never been used for the simulation of water fluxes in CZ. Water content, depth to groundwater, and climate data collected in 2012 and 2013 during a field experiment in the Rio Grande flood plain, New Mexico, were used to calibrate and validate the Hydrus-1D model. Predicted borehole water content agreed well with measurements taken at 15, 30, and 90 cm depths when the groundwater levels were nearly stable (coefficient of determination [R2] of 0.83 and root-mean square error (RMSE) of 0.023 cm3/cm3 for CZ; R2=0.90 and RMSE=0.015 cm3/cm3 for RS). Results show that Darcian nodal velocities slowed down (∼0 cm/day) within the top 60 cm of the CZ profile therefore limiting evaporation losses. However, this phenomenon can be a disadvantage for growing shallow-rooted plants.