The negative factors which since pre-independence to present period have contributed significantly to the fearful depletion of flora and fauna in India can be outlined as follows : (i) The expansion of railways, agriculture, commercial and scientific forestry and mining activities during the colonial period have inflicted greatest damage on Indian forests. (ii) ‘Enrichment plantation’ promoting a few favoured species and eliminating other species, e.g. teak monoculture in South India and chir pine plantation in Himalayan region, have damaged the natural forests. (iii) Even after independence, agricultural expansion to meet the food requirement of a huge and growing population continues to be one of the major causes for depletion of forests. (iv) Shifting cultivation or jhumming in the tribal belts especially in the north east and central India have led to deforestation or degradation of forests. (v) Large scale development projects like the river valley projects have contributed significantly to the loss of valuable forests. (vi) Mining causes deforestation and disturbs the natural habitats of many animals and block the migration route of several other species. (vii) Grazing and fuelwood collection lead to depletion of forests resoures according to many environmentalists. However, a substantial part of the fuel and fodder demand is met by lopping rather than felling of entire trees; thus they do not cause total deforestation. (viii) Habitat destruction and over-exploitation. (ix) Hunting and poaching. (x) Environmental pollution and water poisoning. (xi) Forest fires.