Soil Physical Quality as a Basis for Sustainable and Climate-Resilient Land Use in Suboptimal Drylands of Aceh Besar, Indonesia

Abstract

The productivity of tropical dryland soils is constrained not only by limited water availability and low soil fertility but also by unfavorable soil physical properties, which are critical for achieving sustainable and climate-resilient agriculture. This study identified the characteristics and physical constraints of soils under several land use types (LUTs) in dryland areas of Aceh Besar Regency, Indonesia. Undisturbed and disturbed soil samples for physical analysis were collected using sample rings at a depth of 0–20 cm. Each LUT consisted of 5–8 sample plots (20 m × 20 m), with five soil samples taken from each plot. The results showed that soil physical properties in suboptimal drylands vary across land uses. Soil texture, bulk density, porosity, permeability, aggregate stability index, and water holding capacity (WHC) under forest vegetation, cultivated forests, and dryland agricultural systems were relatively better than those in uncultivated areas. In contrast, uncultivated lands exhibited several physical constraints, including coarse texture, high bulk density (1.51±0.01 Mg m −3 ), low porosity (49.13±5.21%), moderately rapid permeability (21.48±3.12 cm h −1 ), unstable soil aggregates (0.43±0.0021), and low WHC. Improving soil physical quality is essential for enhancing productivity and strengthening climate resilience in dryland systems. This can be achieved through the application of organic amendments such as biochar, compost, manure, and mulch (cover crops), which contribute to sustainable soil management and improved ecosystem functioning.