Hog‐Manure‐Recovered Struvite: Effects on Canola and Wheat Biomass Yield and Phosphorus Use Efficiencies

Abstract

Recovery of manure P as magnesium ammonium phosphate hexahydrate (MgNH 4 PO 4 •6H 2 O), commonly known as struvite, can mitigate the risk of P contamination of surface water bodies from hog operations. The slow release of P from struvite may help improve crop P use efficiency. This greenhouse bioassay evaluated the agronomic effectiveness of liquid hog manure recovered struvite. Struvite, monoammonium phosphate (MAP), and polymercoated MAP (CMAP) were evaluated for canola (Brassica napus L.) grown in rotation with spring wheat (Triticum aestivum L.) in two low soil test P (Olsen P < 6 mg kg −1 ) soils: a sandy Gleyed Regosol (Typic Haplaquent) and a clay loamy Orthic Black Chernozem (Udic Boroll). The fertilizers were applied either in the seed row or in a sideband at 1.1 and 2.2 g P m −2 rates. In both soils, struvite produced canola dry matter (DM) yield (DMY, 2.4 g kg −1 soil), P uptake (5.9 mg P kg −1 soil), P recovery efficiency (43%), and agronomic efficiency (0.15 g DM mg −1 P) that were similar to those of MAP and CMAP in the first crop phase. Moreover, at the 2.2 g P m −2 rate, struvite produced significantly greater canola DMY than MAP in the second crop phase and both MAP and CMAP in the third crop phase. Overall, wheat did not produce significant responses to P fertilization. These results indicate that struvite recovered from liquid hog manure can supply sufficient P to sustain yields and P use efficiency matching or exceeding those for MAP.Abbreviations: AE, agronomic efficiency; CMAP, polymer-coated monoammonium phosphate; DM, dry matter; DMY, dry matter yield; EC, electrical conductivity; ICP-OES, inductively coupled plasma optical emission spectrometry; MAP, monoammonium phosphate; PRE, phosphorus recovery efficiency; PU, phosphorus uptake; RO, reverse osmosis; STP, soil test phosphorus. Intensive hog production in western Canada generates manure at an estimated rate of >16 Tg annually (Hofmann, 2013). Manitoba, which has the third largest hog population (2.8 million as of January 2014) of all Canadian provinces (12.7 million hogs total), accounts for about 20% of Canada's daily hog manure output (Statistics Canada, 2014a).Manure from hog operations is typically applied on agricultural land as a source of nutrients for crops. Current regulations in many jurisdictions, including Manitoba, now require that manure be applied based on crop P needs. This is because the N/P ratios of hog manures (2:1-4:1) are typically lower than crop uptake ratios (4:1-7:1) (Nelson and Janke, 2007), with the result that repeated manure applications based on crop N needs can lead to excessive soil test P (STP) levels. Therefore, the amount of hog manure that can be applied on agricultural land without risking noncompliance with the increasingly stringent regulations is limited. Finding suitable land proximal to hog operations can be a daunting task, particularly where soils have received repeated manure applications. This Core Ideas: Yeukai Katanda• Struvite recovered from liquid hog manure is a slow-release P source....

Bioavailability of phosphorus from composts and struvite in acid soils

“…Some authors reported different rates of P released from struvite due to edaphic properties and crop characteristics, Table 3. Olsen P (mg kg -1 soil) of all treatments during the incubation time such as root exudates (González-Ponce et al, 2009;Ackerman et al, 2013;Katanda et al, 2016;Talboys et al, 2016). Ackerman et al (2013) found lower production of biomass per unit of P from struvite, compared with MAP and PCMAP, due to a lower initial solubility of struvite in the alkaline soil used.…”

Options for Improved Phosphorus Cycling and Use in Agriculture at the Field and Regional Scales

“…Further, Weissengruber et al (2018) concluded that potentially toxic element and persistent organic pollutant accumulations would be low to negligible even after 200 yr of struvite application (at 11 kg P ha −1 yr −1 ). In addition to recovery from municipal wastewater, recovery and use (as a fertilizer) of struvite from human urine, livestock urine and manure, and food processing wastes have received considerable attention (Antonini et al, 2012; Achat et al, 2014; Uysal et al, 2014; Katanda et al, 2016; Brown et al, 2018; Katanda et al, 2019; Muhmood et al, 2019). Struvite P recovery potential from municipal and agricultural wastewater ranges from 10 to 99%, depending in part on the process used and the source and P concentration of the waste product (Jordaan et al, 2010; Egle et al, 2016; Peng et al, 2018; Muhmood et al, 2019).…”

“…Struvite is generally considered a slow‐release fertilizer due to its low solubility in water and relatively slow dissolution in soil (Bridger et al, 1962; Cabeza et al, 2011; Achat et al, 2014; Talboys et al, 2016). The value of struvite as a crop fertilizer has been investigated in many recent studies (Gell et al, 2011; Katanda et al, 2016; Degryse et al, 2017; Katanda et al, 2019) and summarized in several thorough reviews (Liu et al, 2013; Rahman et al, 2014; Kataki et al, 2016; Ahmed et al, 2018; Möller et al, 2018; Peng et al, 2018) and one meta‐analysis (Huygens and Saveyn, 2018). …”

“…The dissolution dynamics and agronomic effectiveness of struvite can vary depending on the extraction process used during recovery (Antonini et al, 2012; Peng et al, 2018; Rech et al, 2019), granular form versus powdered (Degryse et al, 2017; Everaert et al, 2017), placement (Katanda et al, 2016; Degryse et al, 2017), crop species (Katanda et al, 2016; Talboys et al, 2016), and soil properties such as pH and P sorption capacity (Liu et al, 2016; Degryse et al, 2017; Everaert et al, 2017; do Nascimento et al, 2018). Nitrification and plant uptake of ammonium from struvite may contribute to P dissolution through soil acidification, especially when struvite particle size is small (Bridger et al, 1962; Vaneeckhaute et al, 2016).…”

4R Management of Phosphorus Fertilizer in the Northern Great Plains

“…Struvite is not nearly as soluble as MAP (Degryse et al, 2017), so the risk of salt toxicity to seedlings is much less for struvite (Katanda et al, 2019). Growth chamber experiments in Manitoba demonstrated that the P nutritional value of struvite derived from liquid manure was variable, being similar, slightly less, or slightly greater than that for MAP, depending on the soil and crop (Ackerman et al, 2013; Katanda et al, 2016). …”