Application of coconut shell charcoal and NPK fertilizer toward Acacia mangium growth on the soil of ex-limestone mining in Bogor, Indonesia

Limestone mining is an activity that can cause damage and negative impact on the environment. Revegetation is needed to be done so that the damaged land condition can be returned in accordance with its designation. Acacia mangium is one of the species that can be used in revegetation of mining area. This study aims to increase the A. mangium growth response at the limestone mining land that can be used as a tool for consideration in revegetation activities. The design used in this experiment was a complete randomized design (CRD) factorial with 2 factors. The first factor was the application of coconut shell charcoal and the second factor was the application of NPK fertilizer. The results showed that the addition of coconut shell charcoal could give effect to the number of nodules with the best dose of 90 g and NPK fertilizer was able to give effect to the growth of diameter and the number of root nodules with the best dose of 15 g