Introduction

Forests Our Lifeline of Class 7

India is one of the twelve mega bio-diversity countries of the world. With about 47,000 plant species India occupies tenth place in the world and fourth in Asia in plant diversity. There are about 15,000 flowering plants in India which account for 6 per cent in the world's total number of flowering plants. The country has many non-flowering plants such ass ferns, algae and fungi. India also has 89,000 species of animals as well as rich variety of fish in its fresh and marine waters.

Nature has been very kind to man. Ever since its appearance on the earth’s surface man has been dependant on nature for his subsistence. He needed edible plants and animals.

In the initial stages of the history of economic development, man identified these natural gifts available around him and learnt to use them. Everything that comes from nature has some utility for man but its utilization is possible on the availability of appropriate technology. Although natural products exist over the earth’s surface even during pre-historic times, man had neither the tools nor the technology to use them. Land, sunshine, wind, forest and wildlife were present much before the appearance of man on the earth. With time he could learn to cultivate the land, grow crops by protecting different plants, and run the wind and water mills by using the wind and water energy. Similarly for centuries coal and mineral oil were present below the earth’s surface but he had no technology to utilize them. Hence these natural materials turned into resources only when they could be used. Diversity characterizes most living organisms and our earth supports something like 5 to 10 million species of plants and animals (IUCN, 1980) which have been the result of 3 billion years of evolution involving mutation, recombination and natural selection.

Natural Vegetation:

Refers to a plant community which has grown naturally without human aid and has been left undisturbed by hurnans for along time. This is termed a virgin vegetation. Thus, cultivated crops and fruits, orchards are a part of vegetation but not natural vegetation. India's natural vegetation has undergone many changes due to several factors such as the growing demand for cultivated land, development of industries and mining, urbanisation and over-grazing of pastures. The vegetation cover of india in large parts is no more natural in the real sense. Except in some inaccessible regions like the Himalayas, the hilly region of central India and the marusthali, the vegetation of most of the areas has been modified at some places, or replaced or degraded by human occupancy.