Oil palm plantation in ex-coal mined site: A case study in East Kalimantan, Indonesia

Abstract

The oil palm plantation in the ex-coal area is new hope for renewable energy. Oil palm is also known as an important source of raw material for many products and the plantation area is expanding. Mine reclamation area may be suitable for oil palm but there are challenges for its development. This study aims to determine the land suitability of the ex-coal mined site for oil palm and evaluate the growth and yield compared to the plantation in commercial cultivation from the previous studies. The study in a coal mine company in Indonesia used soil quality, rainfall, vegetation growth and yield production data in 4, 5, 6 and 7-year-old-plantations. The result showed that the ex-coal mined site referred to S2 or suitable with limited factors in the 7-year-old-plantation area, while S3 or marginal soil in other areas. The soil mostly had low nitrogen content and cation exchange capacity as if the initial condition before mining and required additional manure and nitrogen fertilizer. Water management was required due to the sandy loam texture in the 4-year-old-plantation area to protect water availability by the silt pit or cover crops, especially in the dry season. The plant height showed a positive correlation to the land suitability, although the plant height was far lower than in commercial cultivation. The yield production also confirmed a rapid increase after castration in 2019 for 4, 5 and 7-year-old-plantation areas. The findings are useful for considering potential plant species of choice in the ex-coal area.