Study of ESP-SAR in ex-gold mining soil ameliorated with geo-biomaterial

Abstract Implementing amelioration technology on agricultural land needs consideration of salinity and alkalinity issues. Salts, such as Na + , can cause soil particles to disperse. The variability of ESP-SAR (exchangeable sodium percentage - sodium adsorption ratio) in ex-gold mining soil (ex-GMS) ameliorated with geo-biomaterial based on sub-bituminous coal (SC), sub-bituminous coal activated with NaOH (SC-NaOH), and young coconut waste biochar (B-YCW). This research has used a completely randomized design (CRD) with ten treatments and three replicates, namely: (A) control; (B) 100% SC; (C) 100% SC-NaOH; (D) 100% B-YCW; (E) formulation of SC + B-YCW: (1) 75% + 25%; (2) 50% + 50% and (3) 25% + 75%; (F) formulation of SC-NaOH + B-YCW: (1) 75% + 25%; (2) 50% + 50% and (3) 25% + 75%. The effect of 100% B-YCW and SC-NaOH was significant on ESP-SAR in ex-GMS has increased by 8.59% and 0.57 meq L −1 ; 8.46% and 0.36 meq L −1 ,respectively, compared to the control. The correlation between ESP and SAR was a significant relationship (r = 0.768**) and could be predicted using a linear equation ESP = 15.067(SAR) + 4.9741; R 2 = 0.5878 in ex-GMS ameliorated with geo-biomaterial. The ESP-SAR was significantly related to the pH (r = 0.394* and 0.605**) and Na-exch (r = 0.590** and 0.653**) of ex-GMS ameliorated with geo-biomaterial. The implementation of amelioration technology should also consider the sodicity (ESP-SAR) prediction model through geo-biomaterials in improving the quality of polluted soil.