Effects of different polymer hydrogels on moisture capacity of sandy soil

Abstract

In arid and semi-arid regions, efficient utilization of available water necessitates the adaptation of appropriate water management practices. One such approach is through soil conditioners like polymer hydrogels. The application of polymer hydrogels aids efficient management of water in agricultural production by increasing water holding capacity and improving water conservation of sandy soils. This has led to practical applications of these materials particularly in arid regions and countries, where water is the limiting factor for plant production. Therefore, the ultimate objective of this study was to address the impacts of different polymer hydrogels such as potassium polyacrylate (PH1), starch-acrylonitrile (PH2), starch-acrylic-acid (PH3) and polyacrylic acid (PH4) on the moisture capacity of sandy soils from sand dune. The sandy soils contained >95% sand. Maximum rate of water absorption of polymers (PH1, PH2, PH3 and PH4) were 174, 38.75, 21.7 and 201.1 times their weight respectively. Four polymer hydrogels with three treatments (0.25:0.75, 0.5:0.5 and 0.75:0.25; v/v) were used in the experiment with four replication. With respect to the untreated soil, addition of polymer hydrogels increased significantly full moisture capacity (FMC) and smallest moisture capacity (SMC) for for all polymer: sand mixtures. PH1 recorded highest FMC and SMC than all four polymers. The results suggest that addition of a potassium polyacrylate to sandy soils is more effective polymer hydrogel at increasing moisture capacity in sandy soils.