Impact of conditioners added to soil of different bulk density on saturated water content and water holding capacity over a six-day manipulative experiment

Abstract Artificial superabsorbents specifically influence the water absorption capacity of soils. The article compares four commercially available synthetic superabsorbents mixed with soil of different bulk density. Soils at each of nine study sites were sampled at five spots minimally to get site-representative soil samples. The soils were mixed with hydrophilic substances such as acrylamide, polyacrylic acid, cross-linked polymers and potassium polyacrylate. Both amended and non-amended soil was then put into sampling rings, which open bottoms were exposed to water through a filter paper to be soaked via capillary action to the saturated water content of the soil (θ S ). Then the samples were drained by passive capillary drainage through another piece of 4-layer filter paper. Periodical weighing of the samples enabled us to determine and calculate water-holding attributes. Following the 114 hours of the experiment, the samples were oven-dried at 105 °C to determine their bulk density. The passive capillary drainage showed higher loss of water from the amended treatments though they kept a larger volume of water than the control treatments over the period of experiment. Keeping recommended concentrations of the substances by the producers led to different efficiencies especially in soils with higher bulk densities.