Influence of Land-Use Type on Black Soil Features in Indonesia Based on Soil Survey Data

Black soils refer to soils with black, thick upper layers containing 0.6% or more soil organic carbon in the tropical region. This high organic carbon content makes these soils essential for climate change control and food production. In Indonesia, black soils are found under forests, shrublands, and grasslands in tropical monsoon and savannah climates. Land clearing for agricultural uses will change black soil properties; however, knowledge of change (level, direction, and sensitivity) is limited. Meanwhile, soil surveying records land-use types and collects soil samples, resulting in voluminous legacy soil data. This study aimed to compare the mean difference in soil properties between two land-cover/use types. We used 142 black soil datasets containing legacy data on particle size distribution (sand, silt, clay), pH, soil organic carbon (SOC), total nitrogen (TN), available P 2 O 5 (AP), and exchangeable cations (Ca, Mg, K, Na). We calculated the Hedges’s g-index for effect size assessment and performed a Welch’s t -test for significant differences. The results show that, compared to the forest, the agricultural dryland and monoculture home gardens have a large effect size and trigger changes in many soil properties. In contrast, mixed home gardens and paddy fields have a small effect size. In decreasing order, the black soil properties sensitive to change are TN > SOC = exchangeable K > exchangeable Mg = available phosphorus = pH = exchangeable Na > sand = silt = clay > exchangeable Ca. The results suggest that a combination of home gardens and paddy fields better supports food security and mitigates climate change in black soils. In addition, the legacy soil data can be used to monitor soil property changes.