AeroHydro Culture: An Integrated Approach to Improve Crop Yield and Ecological Restoration Through Root–Microbe Symbiosis in Tropical Peatlands

Tropical peatlands in Indonesia are increasingly degraded by conventional oil palm practices involving drainage and chemical fertilizers. This study evaluates AeroHydro Culture (AHC), a method applying microbe-enriched organic media aboveground, as a sustainable alternative that maintains high groundwater levels while supporting plant productivity. Field trials were conducted at two sites: a managed plantation in Siak and a degraded, abandoned plantation in Pulang Pisau. Ten months after treatment, AHC plots showed development of aerial-like lateral roots, improved chlorophyll levels, and increased arbuscular mycorrhizae colonization (from 0–46% to 22–73% in Siak, and 1.7–20% to 16–60% in Pulang Pisau). In Siak, AHC significantly increased IAA-producing and proteolytic bacteria in the 0–25 cm soil layer and raised oil palm yield by 36% over controls. This yield benefit was sustained in 2025, five years after the initial application. In Pulang Pisau, AHC also enhanced microbial abundance and promoted growth in the native species Shorea balangeran, suggesting its potential for reforestation. Drone imagery confirmed visible long-term differences in canopy color, supporting lasting physiological improvement. These results demonstrate that AHC promotes plant–microbe symbiosis, enhances nutrient acquisition, and sustains oil palm yield under saturated conditions. AHC offers a promising strategy for peatland rehabilitation where ecological recovery and agricultural productivity must be achieved in parallel.