The chemical properties of pH, CEC, Ca2+, and Mg2+ were determined. Soil pH was determined using a pH electrode (Seven Excellence S479-uMix, Mettler-Toledo, Switzerland) in a 1:2.5 soil:water suspension. Ca2+ and Mg2+ contents were measured by using inductively coupled plasma‒optical emission spectrometry69 (link). CEC was determined by using a microplate reader (Synergy 2, BioTek, USA) following extraction using [Co(NH3)6]Cl3 (ref. 70 (link)).
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