The Effect of Succession on Plant Diversity and Composition in Post-Gold Mining Land in Monterado Subdistrict
Gold mining activities in forest areas are one of the disturbances to forests. Gold mining activities can have an impact on environmental conditions both physically, chemically and biologically. Physically, it can be seen from the opening of a large area of land and changing into a barren land in the form of a desert containing tailing. Chemically, it is known from water, soil and vegetation pollution due to the use of hazardous substances such as mercury. Biologically, it can be seen from the loss of vegetation and organism associations.
Over time, post-gold mining land will undergo succession. The initial condition of the land that was just abandoned by the miners in the form of open and barren land will gradually be overgrown with pioneer species that are tolerant to the conditions of post-gold mining land that are poor in nutrients. The results of Roberto's (2012) study on pioneer plant studies on post-gold mining land in Mandor Nature Reserve showed varying levels of regeneration and understory plants, both in number and type, on post-mining land aged 1-3 years, 4-5 years, 6-10 years, and 11-15 years. Likewise, gold mining activities carried out in Monterado have resulted in damage that has a negative impact on environmental conditions including stand composition.
The initial condition of the land that was just abandoned changed over time to form a new ecosystem gradually. This can be seen from the presence of vegetation types that grow on post-mining land from several age ranges. On land that has just been abandoned, it is still in the form of barren land, on land that is about one year old there are grass species, and on land more than 10 years old the types of vegetation that grow are more diverse. In the post-gold mining area in Monterado, there is no information about its natural succession. What types of plants have successfully grown in the area, what types dominate, the diversity of plant species that exist, whether their growth is complete or not, and differences in vegetation composition types in the area are part of this research problem. Information on natural vegetation succession on post-gold mining land is needed as a basis for further handling. Based on preliminary surveys on post-gold mining land in Monterado Subdistrict, there are four different tailing age levels namely 10 years. Therefore, research on succession of post-gold mining land in Monterado needs to be done. This study aims to obtain information about the levels of natural vegetation succession that occur on post-gold mining land in Monterado.
This research was conducted using survey method through vegetation analysis by double plot size 20 m x 20 m. Placement of plots deliberately based on the tailing period of post-gold mining which were: 10 years. The results showed that kinds of shrubs were found at all age levels of post-gold mining areas. The type of woody plants at the seedling level was found in all periods of post-gold mining areas, whereas saplings , poles and trees were only found in post-gold mining areas at age levels > 10 years. Based on vegetation analysis , it showed that Ischaemum rugosum and Melastoma malabathricum L. dominated at all age levels of post-gold mining. Seedlings in post-gold mining areas at all age levels were dominated by Dillenia suffruticus . The species diversity index showed that it was still low on post-gold mining areas in Monterado.Until the tailing age > 10 years , succession was still at the level of competition , so it was concluded to be slow . To accelerate succession , revegetation , land restoration , and people awareness should be undertaken.