Acidification affects soil bicarbonate concentration, infiltration rate, and Kentucky bluegrass performance

Abstract Golf courses are increasingly reliant on suboptimal water sources, particularly in arid regions, many of which exhibit elevated levels of dissolved bicarbonate (HCO 3 − ). The assessment of bicarbonate levels in irrigation water, in conjunction with the examination of other ions, are believed to be primary contributors to soil physical issues, including diminished infiltration rates and restricted plant rooting. Bicarbonate and, to a lesser extent, carbonate (CO 3 2− ) are commonly present in high‐pH water. While their concentrations in irrigation water are variable, the primary concern lies in the imbalance of these ions with Na, Ca, and Mg. Such imbalances can lead to the precipitation of relatively insoluble Ca and Mg carbonates. The removal of soluble Ca and Mg through precipitation leaves Na in solution, promoting sodic conditions that deteriorate soil structure and potentially clog soil pores. While high levels of bicarbonate and sodium in irrigation water suggest that acidification is required, the question arises as to whether irrigation water acidification is necessary when ratios of Ca/Mg and HCO 3 /CO 3 are high but levels of sodium are low. The study was conducted at New Mexico State University and involved four irrigation water treatments, including N‐pHuric acid and WaterSOLV™ Curative, which are intended to decrease HCO 3 /CO 3 in irrigation water. After 2 years, Kentucky bluegrass irrigated with N‐pHuric acid‐amended water exhibited greater soil hydraulic conductivity compared to other treatments. During the first year, Kentucky bluegrass irrigated with N‐pHuric acid demonstrated the greatest visual quality and the greatest Dark Green Color Index; however, these results were not apparent in the second year.