The drive was carried out near mines in Yercaud, Salem and Coimbatore
Afforestation initiatives in mine spoils in Salem and Coimbatore districts carried out by the Institute of Forest Genetics and Tree Breeding (IFGTB) during the period 2002-06 has been lauded by the National Afforestation and Eco-Development Board under the Union Ministry of Environment and Forests in a documentary film.
The Director of IFGTB, N. Krishna Kumar, said that reclamation of mine spoil land, rehabilitation and restoration of de-graded areas has come in for appreciation. IFGTB carried out the drive in one hectare in areas closer to bauxite mine near Yercaud, in two hectares near magnesite mine in Salem and another two hectares near the lime stone mine in Coimbatore.
Mine spoils is a mixture of minerals, metals, rock fragments, and sub-soils that result from surface mining operations. Dumping of mine spoils had always been a problem for health and environment. To ameliorate the mine spoils, top spoil is spread over it before planting saplings, because top soil has good structure, water holding capacity and beneficial microbes which are very essential for plant growth.
Suitable tree species such as Acacia Auriculformis, Casuarina equisetfolie and Gmelina were inoculated with culture beneficial microbes such as Arbuscular mycorrhizal fungi, Rhizobium Phospobacterium and Azospirillum and then grown in collected mine spoils as potting media.
Seedlings grown in mine spoils with these bio-fertilisers have been improved in terms of growth and biomass. Thus, quality improved seedlings with bio-fertilisers were directly transplanted at the sites.
After this, growth and survival rate are monitored on an annual basis. Seedlings inoculated with beneficial microbes had higher growth and survival rate.
Method of using beneficial microbes for afforestation in mine spoils is cost effective and environment friendly. The reclaimed and rehabilitated sites are fast restoring, increasing the bio-diversity by attracting host of insects, butterflies and birds.
Ecological engineering using soil microbes is a sure way to restore the degraded areas in which public participation is essential, Mr.Krishna Kumar added. Now, IFGTB has specialised teams in the area of mine spoil restoration.