Studies on Soil Physical Quality of PT Coal Mine Reclamation Land, Sumber Bara Abadi, Kutai Kartanegara Regency, Indonesia

Evaluation of the physical quality of soil on coal mine reclaimed land is needed to monitor and evaluate reclamation activities aimed at restoring and improving soil quality. The results of the evaluation of the quality of the physical properties of the soil are presented as an index of the physical quality of the soil which can be used as input for taking further soil management actions. This research aims to determine the characteristics of the physical properties of the soil and assess the physical quality of the soil on coal mine reclaimed land as outlined in the soil physical quality index (IKFT). This research was carried out from August to November 2022 on the reclaimed coal mine land of PT. Sumber Bara Abadi, Sumber Sari Village, Sebulu District, Kutai Kartanegara Regency, East Kalimantan, Indonesia. The method used in this research was a survey. Determining the location of soil samples was carried out using a purposive method based on reclaimed land cover, reclamation age, and slope. Data analysis was carried out directly in the field and soil analysis in the soil laboratory of the Faculty of Agriculture, Mulawarman University. The assessment of the IKFT is carried out after the analysis of the physical characteristics of the soil has been determined. The IKFT is measured by following a three-step procedure, namely identification of indicator data sets, interpretation of indicators, and integration of all indicator scores into one overall IKFT value. The research results show that (1) the physical characteristics of the soil are: soil texture varies between clay, clay loam, and sandy clay loam; Soil porosity is classified as poor and good; stability of aggregate is classified as less stable aggregate to very stable; Soil permeability is relatively slow and moderate; bulk density is classified as medium and slightly dense; surface rocks are abundant; the depth of the solum is classified as shallow and medium; and (2) the physical quality of the soil on reclaimed coal mine land is classified as rather low and moderate with limiting factors including a large amount of surface rock, large bulk density, low solum depth, and low aggregate stability.