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- Our country 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 as ferns, algae and fungi. India also has approximately 90,000 species of animals as well as a rich variety of fish in its fresh and marine waters.
Natural vegetation refers to a plant community which has grown naturally without human aid and has been left undisturbed by humans for a long time. This is termed as a virgin vegetation. Thus, cultivated crops and fruits, orchards form part of vegetation but not natural vegetation.
- Flora = Plants
- Fauna = Animals
DIVERSITY OF PLANTS & ANIMALS
The huge diversity of Plants & Animals is due to the following factors:
- Relief | Land: Land affects the natural vegetation directly and indirectly. The nature of land influences the type of vegetation. The fertile level is generally devoted to agriculture. The undulating and rough terrains are areas where grassland and woodlands develop and give shelter to a variety of wild life.
- Soil: Different types of soils provide basis for different types of vegetation. e.g.: Sandy Soils (Desert) – Cactus & thorny bush, Deltaic Soils – Mangroves & Deltaic vegetation.
- Temperature: The character and extent of vegetation are mainly determined by temperature along with humidity in the air, precipitation and soil.
- Photoperiod: The variation in duration of sunlight at different places is due to differences in latitude, altitude, season and duration of the day. Due to longer duration of sunlight, trees grow faster in summer.
- Precipitation: Areas of heavy rainfall have more dense vegetation as compared to other areas of less rainfall.
TYPES OF VEGETATION
Tropical Evergreen Forests
- Heavy Rainfall (>200cm)
- Western Ghats, Tamil Nadu coast, Lakshadweep & Andaman and Nicobar Islands, North-East India.
- Flora: ebony, mahogany, rosewood, rubber and cinchona.
- Fauna: Elephants, monkey, lemur, deer, rhinoceros etc
Tropical Deciduous Forests (Moist + Dry)
- Most Widespread forests in India
- also called ‘Monsoon Forests’
- Moderate Rainfall (70-100 cm)
- Further divided into:
- Moist Deciduous: 100-200 cm rainfall. Teak is the most dominant species of this forest. Bamboos, sal, shisham, sandalwood, khair, kusum, arjun, mulberry are other commercially important species.
- Dry Deciduous: 70-100 cm rainfall. Teak, Sal, Peepal, Neem grow in these forests.
- The common animals found are lion, tiger, pig, deer and elephant.
The Thorn Forests & Scrubs
- Rainfall is less than 70 cm
- Vegetation consists of mainly thorny trees and bushes
- Acacias, palms, euphorbias and cacti are the main plant species.
- Trees are scattered and have long roots penetrating deep into the soil in order to get moisture.
- The stems are succulent to conserve water.
- Leaves are mostly thick and small to minimize evaporation.
- Common animals are rats, mice, rabbits, fox, wolf, tiger, lion, wild ass, horses and camels.
Montane Forests (Mountain Region)
- The wet temperate type of forests are found between a height of 1000 and 2000 metres. Evergreen broad-leaf trees such as oaks and chestnuts predominate.
- Between 1500 and 3000 metres, temperate forests containing coniferous trees like pine, deodar, silver fir, spruce and cedar, are found
- At high altitudes, generally more than 3,600 metres above sea-level, temperate forests and grasslands give way to the Alpine vegetation. Silver fir, junipers, pines and birches are the common trees of these forests.
- These are used extensively for grazing by nomadic tribes like the Gujjars and the Bakarwals.
- At higher altitudes, mosses and lichens form part of tundra vegetation.
- Common animals here are Kashmir stag, spotted dear, wild sheep, j ack rabbit, Tibetan antelope, yak, snow leopard, squirrels, Shaggy horn wild ibex, bear and rare red panda, sheep and goats with thick hair.
- The mangrove tidal forests are found in the areas of coasts influenced by tides.
- Dense mangroves are the common varieties with roots of the plants submerged under water.
- The deltas of the Ganga, the Mahanadi, the Krishna, the Godavari and the Kaveri are covered by such vegetation.
- In the Ganga- Brahamaputra delta, sundari trees are found, which provide durable hard timber. Palm, coconut, keora, agar, also grow in some parts of the delta.
- Royal Bengal Tiger is the famous animal in these forests. Turtles, crocodiles, gharials and snakes are also found in these forests.
- India has approximately 90,000 animal species and about 2,000 species of birds.
- They constitute 13% of the world’s total.
- Some animals and their habitats:
- Elephants: hot wet forests of Assam, Karnataka and Kerala.
- One-horned Rhinoceros: swampy and marshy lands of Assam and West Bengal.
- Wild Ass: Rann of Kachh
- Camels: Thar Desert
- India is the only country in the world that has both tigers and lions.
- Lions: Gir Forest, Gujarat
- Tigers: Different locations in India (50 Tiger Reserves)
- Yak: Ladakh
- Himalayan Animals: Shaggy horned wild ox weighing around one tonne, the Tibetan antelope, the bharal (blue sheep), wild sheep, and the kiang (T ibetan wild ass). Furhter more, the ibex, bear, snow-leopard and very rare red panda are found in certain pockets.
- India has a total of 18 Biosphere Reserves, 103 National Parks & 543 Wildlife Sanctuaries.
LIST OF BIOSPHERE RESERVES
- Gulf of Mannar
- The Nilgiris
- Nanda Devi
- Great Nicobar
- Dibru Saikhowa
- Great Rann of Kachh
- Cold Desert
- Sechalam Hills