It will take decades, even a century for the soil and vegetation to recover in former gold mining pits in Surinam's tropical forest. There are ways to accelerate recuperation, but the best solution is making local communities aware that gold mining is harmful to their own environment.
During the past ten years small-scale gold mining has been practiced within Brownsberg Nature Park, 120 kilometres south of Surinam's capital Paramaribo. Often this practice was illegal. Reason for the manager of the nature park, Stichting Natuurbehoud Suriname (Stinasu) to study the gold mining in order to get the local communities which are involved in this practice to look for alternatives.
Alterra studied the consequences of the mining on the forest vegetation. According to Eric Arets of Alterra, the gold mining is small scale, but it has profound impact on the soil and vegetation. 'First they remove the vegetation and the top soil. Then they flush the deeper gold-bearing soil with high pressure water jets. This forms slurry, which is treated with mercury in order to precipitate the gold.'
Arets and his colleagues found that the vegetation on the spots of the mining pits was utterly destroyed. 'Recovery of the original vegetation would take decades, maybe hundred years.' Initially the only plants that grow on the former mining pits are blanket forming lianas as Bubinia guiansensis and Machærium myrianthum and invasive weeds as Senna alana. And these plants slow down the development of other woody vegetation.
It is possible to accelerate the recovery of the forest. First, the researchers recommend reinstalling the top soil that is removed by the gold mining, in order to provide a fertile environment for recovery. Second, the lianas can be removed in order to give other plant species a chance. And third, it is possible to plant indigenous plants.
On the long term the best solution for the nature park is that people from local communities stop with gold mining. This means that other, more sustainable, livelihood opportunities need to be developed for people depending on gold mining. According to Arets the profit is minimal and the damage for the park quite extensive.
It is also a matter of creating awareness, says Arets, because gold mining threatens the health of the people who are mining. The researchers found that the mercury did not form a threat to the gold mining pits. 'But other studies show that the mercury concentrations in the nearby Brokopondo Lake have increased, contaminating food chains in that ecosystem.'
Alterra report 1359: Arets, E.J.M.M., P.J. van der Meer, N.W. van den Brink, K. Tjon, V.P. Atmopawiro and P.E. Ouboter; Assessment of the impacts of gold mining on soil and vegetation in Brownsberg Nature Park, Suriname.