1. Successful afforestation in Mine spoils
Afforestation in mine spoils with beneficial microbes and suitable tree species
Dr. A. Karthikeyan
Scientist E
Institute of Forest Genetics and Tree Breeding
(Indian Council of Forestry Research and Education)
Coimbatore – , Tamilnadu, India
Mine Spoils
In India, more than 0.9 million hectares of land is under mining and mining activities on these lands have created wide spread environmental damage that severely affect not only the landscape but also the social well being. Moreover, ecological problems found at mining sites pose health hazards to nearby residents like high incidence of asthma, silicosis, and stomach ailments due to the mining dust and contamination of water. Mining also has led to discharge of millions of tons of waste rock soil called mine spoils which have been dumped over millions of hectares as wastelands. Afforestation of these mine spoils is very essential to over come the health hazards and ecological problems. But, afforestation of mine spoils has been difficult because it has low water holding capacity, lacks topsoil, deficient in Nitrogen and Phosphorus. Using conventional restoration techniques of grading, re -soiling and fertilizing of mine spoils, the cost may go in millions. However planting of trees on mine spoils is an excellent alternative method for Bio remediation. To deliver it’s full potential for improved plant growth it must retain the biological properties. Therefore, it is essential to introduce the beneficial microbes in mine spoils along with the suitable trees for the better afforestation, Instiute of Forest Genetis and Tree Breeding (IFGTB), Coimbatore brought out a technology for successful afforetation in mine spoils using beneficial microbes.
Technology
Mine spoils lacks beneficial microbes as the top soil was removed during mining. Instead of using top soil for planting activities the top soil properties such as beneficial microbes (bacteria and fungi) were used in afforestaton of mine spoils. The sieved mine spoils of bauxite, magnesite and lime stone were collected and used as potting media for the selected tree seedlings under nursery conditions the beneficial microbes particularly Arbuscular mycorrhizal fungi, Plant Growth Promoting Rhizobacterias and Nitrogen fixing bacteria were isolated and inoculated to the selected tree seedlings of Acacia auriculiformis, Casuarina equisetifolia and Eucalyptus camaldulensis and transplanted at Bauxite. Magnesite and lime stone mine spoils.
Bauxite Mine spoils
Beneficial microbes
AM Fungi
Seedlings inoculated with beneficial microbes
Frankia
Phoshpho bacteria
Rhizobium
Successful afforestation in Mine spoils
IFGTB has done successful afforestation in bauxite, magnestie and lime stone mine
Spoils of Tamilnadu using the beneficial microbes.
IV year after planting
III year after planting
Bauxite Mine spoils
II year after planting
I year after planting various tree species with beneficial microbes
V year after planting
Suitable tree species and microbial combinations for afforestation in mine spoils
Conclusion
This technology reduced the cost of top soil, manures and fertilizers. As the beneficial microbes associated with tree seedlings and there is no additional requirement for chemical fertilizers and manures. Successful plantation with this technology in this study results improvement of soil and environment and this technology could save the cost of top soil and chemical fertilizers.
Tree species
Microbial combinations
Acacia auriculiformis
AM fungi+ Rhizobium
Casuarina equisetifolia
Frankia
Eucalyptus camaldulensis
AM fungi+ Phosphobacterium
E. tereticornis
Afforestation in Magenesite mine spoils
Afforestation lime stone mine spoils