Regenerant wastewater irrigation and ion uptake in five turfgrass species

Abstract

Abstract The effects of wastewater and high concentrations of chloride (Cl), magnesium (Mg2+), calcium (Ca2+), and potassium (K+) on ion uptake and growth of turfgrass species were studied. Simulated water softener regenerated wastewater was prepared based on 1.8 kg KC1 regeneration rate to attain ion concentrations of 30 mM of K+, 100 mM of Ca2+, 100 mM of Mg2+, and 420 mM of Cl‐. It was diluted to 1/5, 1/10, and 1/20 concentrations with tap water for the irrigation studies. Wastewater irrigation did not affect the growth rates of the turfgrass. No significant increase of Ca2+, K+, and Mg2+ uptake was detected under the wastewater irrigation treatment. However, the Cl‐uptake was significantly different between irrigation treatments. It was found that in the spring, in the turf plots irrigated by 1/20 concentration wastewater, an amount equivalent to 60% of the applied Cl‐ was taken up and removed in the Kentucky bluegrass and perennial ryegrass clippings, and more than 80% was taken up by tall fescue, be...