Development of Direct Seeding Implementation for Post Mining Rehabilitation PT Tunas Inti Abadi South Kalimantan Province

Abstract

The method of direct seeding is developed in post mining land in order to give the opportunity to seeds to early adapt with extreem condition in post mining land. This method is implemented in impermanent reclamation land by small mining enterprises caused of its cheap operational cost. The objective of this research is to find out the efficiency of direct seeding method and the suitability of four species; trembesi (Samanea saman), sengon (Falcataria moluccana), sengon buto (Enterolobium cyclocarpum), and randu (Ceiba pentandra) in reclaiming post mining land. The research was conducted implementating three experiments: Experiment I implemented Seeds Physical and Physiological Quality Testing, Experiment II is Forest Species Seeds Adaptation in Post Mining Land, and Experiment III is Effect of Manure Addition in Seed Germination and Growth of Direct Seeding Results. Seed physical quality testing with 1000 grain weight method used the seeds which are classified into small size seeds (sengon and randu) and medium size seeds (trembesi and sengon buto). Based on physiological quality testing, the result of experiment I is 66.67% - 86.67%, Experiment II is 11.2% - 31.6%, and Experiment III is 7.2%-13.2%. Manure addition has significantly influenced the height and diameter growth in Experiment III, but not to the survival rate of plantation. In Experiment II, at the age of twelve weeks, the height of randu plantation was 9.6 cm; trembesi 7.9 cm; and sengon 3.6 cm. The diameter of sengon buto was 4.35 mm; randu 2.12 mm; trembesi 1.91 mm; and sengon 0.98 mm. The result of Experiment III is that average height of sengon buto was 41.5 cm; trembesi 15.4 cm; randu 12.4 cm; and sengon 7.4 cm. The diameter of sengon buto was 5.46 mm; trembesi 2.47 mm; randu 2.42 mm; and sengon 1.12 mm. The survival rate based on the plantation hole in Experiment II was the survival rate of randu and sengon was 66%; trembesi 58%; and sengon bruto 52%. In Experiment III, the higest survival rate was trembesi 72% followed by randu 40%, sengon 38% and sengon buto 28%. From the result of these four species used in the experiment, all of the species are highly adaptive with extreme condition in post mining land and suitable to implement with direct seeding method. It is also identified that size of seed highly influenced the successfulness of direct seeding. Small size seeds are the most suitable one in competition with weed. Direct seeding is more economic with plantation cost of 2 million rupiahs per hectare compared with conventional seeding method with cost of 4.487.500 rupiah per ha.