Securing Topsoil for Rehabilitation Using Fly Ash in Open-Cast Coal Mines: Effects of Fly Ash on Plant Growth

Rehabilitation is an important stage in mining operations for environmental conservation. However, the shortage of topsoil makesit difficult to achieve rehabilitation open-cast coal mines. Securing by mixing soil with fly ash (FA), which treated asan industrial waste, expected solve this issue While FA makes it possible secure topsoiland treat waste simultaneously, high alkalinity and dissolution heavy metals from may inhibit plantgrowth. This study investigated effects on plant growth via vegetation tests simulated mixedwith using Acacia mangium, a species flowering tree: ratios were set 0%, 20%, 40%, 60%, 100%. Thegrowth mangium was inhibited increasing ratio, especially 60% 80%. rate ofAcacia ratio 100% nearly comparable that 40%. Furthermore, there wereno physical characteristics pH conditions at any ratios; meanwhile,the accumulated concentration Al body increased significantly 60%–80%. suggeststhat accumulation Al, inhibits growth, including root its functions, thegrowth mangium. Therefore, most aspect terms concerning use securingtopsoil not but amount body.