Enhancing soil fertility, inorganic fertilizer efficiency, and oil palm productivity through bio-compost application in oxium biodegradable sacks on former mining land-podzols: Insights from a field study in Indonesia

Sandy podzolic soils, prevalent on former mining lands, present significant agricultural challenges due to their coarse texture, depth, acidity, and low fertility. This study evaluated the impact of bio-compost fertilizer, delivered in biodegradable oxium sacks, on soil quality and oil palm productivity in these soils. Conducted over 12 months in a 4-year-old oil palm plantation in East Belitung Regency, Indonesia, the research compared various combinations of bio-compost and inorganic fertilizers with a control group. The findings revealed that the integration of bio-compost with reduced doses of inorganic fertilizers markedly improved soil quality and decreased dependence on chemical inputs. Specifically, applying 50 kg or 75 kg of bio-compost per palm along with 50% or 75% of the standard inorganic fertilizer dose was particularly effective. This approach increased oil palm productivity to 14.50–15.87 tons per hectare per year. The method provides a sustainable solution for the palm oil industry and small farmers, improving soil fertility and productivity in degraded podzolic soils. The use of oxium biodegradable sacks allowed for a gradual release of nutrients. Future research should further explore the potential of bio-compost as a soil conditioner and its long-term environmental impacts across various soil types.