Hydrogel banding improves plant growth, survival, and water use efficiency in two calcareous soils

Abstract

Improving water use efficiency in the agricultural sector, particularly in arid regions, is becoming increasingly important in response to increasing global population and concomitant demand for food, water, and land. The authors performed experiments to determine whether the use of super-absorbent polymers, also known as hydrogels, can increase plant survival, plant growth, and plant water use efficiency. The effect of hydrogel application proportions and application methods on plant survival and growth in clay and sandy clay loam (SCL) soils was investigated. Two pot experiments using Zea mays and Pinus pinea as model plants were performed. The hydrogel was applied at concentrations of 0, 1, 2, 3, and 4 g kg−1 soil in one of two methods: Banding or mixing. Hydrogel effects on water retention in the two soil types were recorded. The results suggest that hydrogel banding at 0.4% application in SCL improves corn's fresh and dry above-ground biomass by 25%, and prolongs survival time of pine seedlings by 90%. Evapotranspiration was greater in soils banded with hydrogel at 0.4% and water use efficiency increased by 10–13% in both soils. Additionally, hydrogel increased water retention of SCL by up to 33% at 100 kPa, but had negligible effects when applied in clay soils. Accordingly, the efficacy of hydrogels in agriculture water conservation depends on using appropriate application methods and quantities. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim