NMSU Student Receives NM WRRI Student Water Research Grant to Study Soil Water Loss and Capillary Forces
By Marcus Gay, NM WRRI Student Program Coordinator
Soil can lose water through evaporation, percolation, and transpiration. Evaporation meaning water vapor lost to the atmosphere, percolation meaning the drainage/downward movement of water, and transpiration meaning water lost through the stomata of plant leaves. In arid and semi-arid regions, there can be even more soil water loss due to high temperatures and sandy soils.
Ryan Zowada, a Chemical Engineering student at New Mexico State University, was awarded an NM WRRI 2020-2021 Student Water Research Grant to explore how to decrease soil water loss by increasing capillary forces in the soil. The project entitled, Biodegradable Porous Hydrogel Water Retaining Additives Designed to Improve Irrigation Efficiency in Arid Climates, aims to add a biodegradable porous hydrogel to soil to act as a water reservoir. The hydrogel would absorb water during irrigation and desorb water during plant water uptake.
According to Zowada, hydrogels have shown they can improve water holding capacity and crop yields in inferior soil; however, the current cost required to apply an adequate amount of super-absorbent polymers in the soil isn’t very economical. One of the objectives of this project is to make the hydrogel porous, which would reduce the cost proportional to the porosity. The water holding capacity is not sacrificed by using porous hydrogels because capillary forces in porous structures increase water uptake and ease plant access to water. The porous hydrogels will also be biodegradable, which resolves the concerns about current super-absorbent polymers that eventually lose water holding capacity and build up in the soil over reapplication.
When asked about the expected results of the project and their significance, Zowada explained, “We expect to see an increase in water holding content for soils with either non-porous or porous hydrogel additives; however, we expect to see a higher increase in plant available water for the porous additive. We expect to see and evaluate a major increase in capillary action when the porous hydrogel is added to the soil compared to both non-porous sample and control soil. Finally, we expect to see a reduction in economic cost of hydrogel implementation by making 30 to 80 percent of the hydrogel volume air and thus improving its candidacy for agricultural practices.”
Zowada is conducting this research project under the guidance of his faculty advisor, Dr. Reza Foudazi, and plans on graduating in Spring 2021 with a PhD in Chemical Engineering. Zowada has a Bachelor of Science degree in Chemical Engineering from NMSU, and has experience conducting research on heavy metal removal from drinking water. After he graduates, Zowada plans on continuing his research as a post-doctoral fellow with a focus on water applications.