ABSTRACT Under water‐scarce conditions, amendments such as superabsorbents and biochar can improve soil water‐holding capacity, but their effects on chemical properties require investigation. This study evaluated AquaSorb superabsorbent (S0, S1, S2: 0, 5, 10 g kg −1 ) and walnut shell biochar (B0, B1, B2: 0, 10, 20 g kg −1 ) on clay loam and sandy loam soils in a completely randomized design. Exchangeable Ca, Na, K, Mg; available P; SAR; CEC; pH; EC e ; and OM were measured after one and six irrigations. In sandy loam, S2 increased K (from 61.1 to 246.1 mg kg −1 ), Mg (2.1 to 3.8), P (7.7 to 9.7), CEC (7.7 to 9.6 meq 100 g −1 ) and pH (7.5 to 8.5). In clay loam, S2 reduced SAR (0.22 to 0.15) while increasing K (from 79.0 to 202.1 mg kg −1 ), pH (7.1 to 7.7) and OM (0.65% to 1.55%). Biochar (B2) in sandy loam raised Mg (2.1 to 3.5 mg kg −1 ), P (7.7 to 12.8) and pH (7.5 to 8.3); in clay loam, it enhanced K (79.0 to 140.6 mg kg −1 ), pH (7.1 to 8.0) and OM (0.65% to 1.9%). Biochar showed greater improvement in soil chemical properties than superabsorbent, suggesting its higher potential for enhancing soil quality under semiarid regions.
Jovzi et al. (Fri,) studied this question.