Effect of struvite (Crystal Green) fertilization on soil element content determined by different methods under soybean cultivation

Abstract

Struvite is regarded as a promising phosphorus fertilizer alternative to mineral fertilizers; however before fertilizing, soil tests should be undertaken to determine fertilizer recommendations. In May 2022, soil was sampled from a pot experiment with the application of phosphorus set up at the Wroclaw University and Environmental and Life Sciences. Chemical analysis of the soil included total and available phosphorus, potassium, magnesium determined by the Egner–Riehm, Mehlich 3 and Yanai methods. The purpose of the article is to compare soil element extraction by three different methods under struvite fertilization and its use in soybean cultivation. The application of these methods indicated an unambiguous increase in soil Mg content after struvite application. Broadcast soybean fertilization affected the phosphorus content of the soil. The results of the study indicated that different extraction methods presented different contents of P from soil. The content of available phosphorus was circa 122–156 mg kg−1 dm, 35.4–67.5 mg kg−1 dm and 100–159 mg kg−1 dm according to the Mehlich, Yanai and Egner–Riehm methods, respectively. A positive correlation was found between the content of Mg and K in soil determined by the Mehlich 3 and Yanai methods, which may suggest that the Yanai method could be introduced into standard soil chemical analysis in Poland. Such a correlation was not found for phosphorus, which is a difficult element to determine due to the multitude of factors affecting its availability.

Struvite and biodiversity to improve phosphorus use in agricultural fields

“…This is especially useful for plants that need a timely fertiliser input for less mobile nutrients such as P (Nkebiwe et al, 2016). Placed struvite has only been sporadically tested but could be advantageous for some plant species such as maize (Jama-Rodzeńska et al, 2023;Talboys et al, 2016).…”

“…spring wheat but not soybean) (Jama-Rodzeńska et al, 2023;Nkebiwe et al, 2016;Talboys et al, 2016). One counterargument could be the high density of struvite particles within the zone where struvite is banded as this may be detrimental to its dissolution.…”