Abstract

The present article is based on the results of a pilot project implemented to improve the physico chemical characteristics of bauxite residue (red mud) in order to make it suitable for rehabilitation through afforestation activities. Prior to interventions, extensive experimentation on various reclamation trials involving combinations of soil amenders along with bacteria and mycorrhizae and selection of suitable tree and grass species was undertaken at the nursery stage for one year. During this period, five tree species and four grass/legume species were selected for afforestation program. Of the selected five tree species, Prosopis juliflora, Acacia nilotica and Pongamia pinnata responded well in combination with 55% red mud +25% FYM + 15% gypsum + 5% vegetative dry dust + bacteria + mycorrihzae, while other two species, Melia azedarach and Acacia tortilis did not survive and thus were replaced by Albizia lebbek and Leucaena leucocephala during pilot implementation in 1.08 ha research plot of red mud of Hindustan Aluminium Company Limited (HINDALCO) at Belgaum, Karnataka, South India. Among the grass and legume species, all the selected four species namely: Brachiaria mutica, Brachiaria decumbens, Stylosanthes scabra and Sesbania sesban responded well at the nursery stage and thus were experimented at the research plot along with the tree plantation. Continuous monitoring on growth pattern of tree and grass species, and soil characteristics revealed remarkable changes in the physico chemical properties of red mud. Apart, toxicity of the planted species and other naturally grown herbaceous flora on the research plot of red mud was also tested for their edibility properties and the results were found encouraging.

Key words: Red mud, bacteria, mycorrhizae, tree species.