Revegetation of muck dumping sites in Indian Himalayan region

Eco-restoration of the muck dumping sites in command area of a hydro-electric power generation project is a matter of serious concern from ecological and social points of view. Realizing the importance of the technological interventions under such situation, CSIR-Institute of Himalayan Bioresource Technology (IHBT), Palampur took up revegetation of 10 closed dumping sites (DS) of National Hydroelectric Power Corporation's (NHPC) Parbati Hydroelectric Project Phase-II in Kullu district, Himachal Pradesh, India, in 2010. These DS are located at 1400 to 2220 m above mean sea level (msl) covering about 9 ha area. Owing to steep slope of DS, a network of retaining walls of stacked stone-filled gabions tied together with mild steel wire-net was made throughout the DS for their stabilization. Considering the agro-climatic conditions of the DS, 11 tree species were selected for plantation. Nursery raised plants of the tree species were planted in gunny bags placed in pits at the sites containing garden soil, organic manure and peat moss. The consortium of selected plant growth promoting rhizo-bacteria (PGPR) was applied at collar level to the tree saplings. After plantation, pelleted seeds of potential herbs and shrubs were also broadcasted. After 1 year the survival rate was 85%. R. pseudoacaciafollowed by Ailanthus excelsaperformed better than other planted tree species. Plant height was maximum in R. pseudoacaciaat all the planting sites. The shrubs and herbs species planted in the targeted sites survived very well and helped in binding the soil over the slopes leading to support to tree species in their establishment and growth.