Post Bauxite Mining Land Soil Characteristics and Its Effects on the Growth of Falcataria moluccana (Miq.)‎ Barneby & J. W. Grimes and Albizia saman (Jacq.)‎ Merr.

Abstract EN

The remediation of opencast bauxite mines in the natural forests of Indonesia is difficult.

We have investigated and contrasted the chemical characteristics of soils from natural forests and mining sites and their effects on plant growth.

The soil pH, total carbon (C), nitrogen (N) and available phosphorus (P) concentrations, cation exchange capacity, C/N ratio, and exchangeable K, Na, Mg, Ca, Fe, and Ni concentrations were determined.

Falcataria moluccana and Albizia saman were then grown in these soils for 15 weeks, and their shoot heights, shoot dry weights, and root dry weights determined.

The post bauxite mining soils’ N, C, and available P concentrations and exchangeable Ca, Mg, and Na concentrations decreased by 75, 75.7, 15.7, 92, 100, and 52%, respectively, in comparison with the natural forest soils.

The shoot and root dry weights of F.

moluccana when grown in the post bauxite mining soils were also lower than those from the natural forest soils.

However, there was no difference in the shoot and root dry weights of A.

saman when grown in the two soil types.

The results suggest that opencast mining decreases the soil fertility, which in turn inhibits the initial growth of tree seedlings, and reduces the carbon stock in the land.