Ecology, Environment and Conservation Paper

MENACES IN THE PLANTED TREE SPECIES ON COAL OVERBUDEN DUMP

Kumar Nikhil

Abstract

Opencast mining severely disturbs land in and around mining areas. The share of opencast mining is progressively increasing in India's coal production. The coal production from opencast mining progressively increased from 14Mt (20% of the total) at the time of coal mine nationalization in 1971-72 to 250Mt (70% of total) by 2000 A.D. All surface mining methods produce dramatic changes in the landscape due to large-scale excavation. It results in the formation of large overburden dumps and huge voids in the mining sites. The country has today thousand hectares of such barren land. Estimation revealed that a total of 1100 hectares of land is being covered by coal overburden dump and by 2000 A.D, 500/vIm of overburden had been handled from coal mines only. The overburden dumps contains overlying soil and rock debris. Further in our country keeping soil layer separately is not in practice. OB Dumps are devoid of required essential plant nutrients, soil micro-flora and fauna. They are prone to leaching of heavy metals and silt erosion during runoff in rainy season. Tree plantation is being practiced and only tool for overburden bio-restoration as they have the ability to restore fertility, accelerates microclimatic conditions and with an economical benefits. During one bio-reclamation experimentation it has been noticed that the tree planted on overburden dump has more foliage content over soil and found 575%, 206.25%, 266.67% and 210% increase in Dalbergia sissoo, Acacia nilotica, Leucaena leucocephala and Azadirachta indica respectively. This implies that plant growth pattern has been changed due to the deviation of physico-chemical and biological characteristics of overburden dump material from normal soil. The increase in the foliage content of planted tree species on overburden dump over soil after two years indicates an alarming situation for timber species planted on overburden dump as the. less height, more number of branching will reduce the economic value. In this paper the factor affecting the change in foliage content of planted species were briefly discussed. The remedial actions were being suggested through experience.