Rehabilitation of open cut coal mine with Paper Mulberry (Broussonetia papyrifera) in Indonesia

Most of the coal is produced from open cut mining in Indonesia. In recent years, Indonesian coal companies are increasing coal production and developing new coal mines in order to accommodate the heavy demand for coal all over the world. However, mining operation of open cut mines gives serious impacts on surrounding environment. Therefore, an appropriate rehabilitation program has to be taken into consideration when the mine plan is designed. The basic concept of rehabilitation in open cut mines is the creation of a stable and self-sustaining land surface in post mine surface involved the creation of conditions suitable for the establishment and permanent development of a dense cover of vegetation. Additionally, the utilization of these lands as other potential economic and use options become to be considered recently. It can be thought that Paper Mulberry is one of efficient species to plant rehabilitation area. This species is a fast growing tree and can grow under warm temperature, subtropical and tropical regions, and various soil conditions. There are a lot of usages in paper mulberry such as making paper, clothing items, and medicine. In this study, application of Paper Mulberry which has two characteristics, fast growing tree and productive use in the disturbed area, was discussed by means of several laboratory and field tests. It was found that 1) hot-water treatment in 80°C for 10 seconds is most effective treatment to improve germination rate (more than 80%), 2) Paper Mulberry can grow up under the rehabilitation area in Indonesian open cut mine and the management term of seedlings in Nursery can be simplified by transplant to the field early though the competition with cover crop has to be taken into consideration, 3) appropriate management of soil texture in the field can promote the growth rate of this species in terms of fiber resources.