Evaluation of electrochemically precipitated struvite as a fertilizer‐phosphorus source in flood‐irrigated rice

Abstract

AbstractPhosphorus (P) is a major contaminant in many wastewater sources and has gained interest due to the role P has in eutrophication of receiving waters. Recycling P from wastewater as the mineral struvite (MgNH4PO4 · 6H2O) could be a promising option to reduce P discharge into receiving waters and could potentially provide an alternative fertilizer‐P source for crop production. The objective of this study was to evaluate the effects of two struvite materials (i.e., electrochemically precipitated struvite [ECST] and chemically precipitated struvite [CPST]) relative to several other common fertilizer‐P sources (i.e., triple super phosphate [TSP], monoammonium phosphate [MAP], diammonium phosphate [DAP], and rock phosphate [RP]) on the response of a pureline rice (Oryza sativa L.) cultivar grown under flood‐irrigation in a P‐deficient, silt‐loam soil (Typic Glossaqualfs) in eastern Arkansas. In 2019, rice grain yield did not differ (P > .05) among fertilizer‐P sources, whereas in 2020, rice grain yield was greater from TSP (13.1 Mg ha−1) than that from ESCT (11.0 Mg ha−1) or CPST (12.7 Mg ha−1). Rice aboveground dry matter, aboveground and belowground tissue and grain P and N concentrations, aboveground and grain tissue P uptake, and aboveground tissue N concentration from ECST and CPST did not differ (P > .05) from those from TSP, MAP, DAP, RP, or an unamended control. The similarities in rice responses compared with other commonly used, commercially available fertilizer‐P sources suggest that struvite materials have the potential to be an alternative fertilizer‐P source option for flood‐irrigated rice production.