Natural vegetation refers to a plant communitywhich has grown naturally withouthuman aid and has been left undisturbed byhumans for a long time. This is termedas virgin vegetation. Thus, cultivated crops andfruits, form part a of vegetation but not naturalvegetation.Virgin vegetation -The virgin vegetation, whichare purely Indian are known asendemic or indigenous species but those whichhave come from outside India aretermed as exotic plants
Photoperiod (Sunlight)The variation in duration of sunlight at different places isdue to differences inlatitude, altitude, season and duration of the day. Dueto longer duration of sunlight,trees grow faster in summer.PrecipitationIn India almost the entire rainfall is brought in by theadvancing southwest monsoon(June to September) and retreating northeastmonsoons. Areas of heavy rainfallhave more dense vegetation as compared to other areasof less rainfall.
TEMPERATURE•Warmer water temperatures will cause population decline for trout,salmon and many other species that require cold water to survive.•Rising ocean temperatures have already caused massive coralbleaching, leading to the collapse of these ecosystems which sustainhuge numbers of fish.WATER•Larger floods are expected to increase erosion levels, reducingwater quality and degrading aquatic habitat.FOOD•Climate change has altered food availability for migratory species;birds arrive on schedule to find their food sources--insects, seeds,flowering plants--have hatched or bloomed too early or not at all.
The following major types of vegetation may beidentified in our country(i) Tropical Rain Forests(ii) Tropical Deciduous Forests(iii) Tropical Thorn Forests and Scrubs(iv) Montane Forests(v) Mangrove ForestsLike its flora, India is also rich in its fauna. It has morethan 89,000 of animal species. The country has morethan 1200 species of birds. They constitute 13% of theworld’s total. There are 2500 species of fish, whichaccount for nearly 12% of the world’s stock. It alsoshares between 5 and 8 per cent of the world’samphibians, reptiles and mammals.
To protect the flora and fauna of the country, the government has taken manysteps.(i) Fourteen biosphere reserves have been set up in the country to protect flora andfauna. Four out of these, the Sunder bans in the West Bengal, Nanda Devi inUttaranchal, the Gulf of Mannar in Tamil Nadu and the Nilgiris (Kerala, Karnatakaand Tamil Nadu) have been included in the world network of Biosphere reserves.(ii) Financial and technical assistance is provided to many Botanical Gardens by thegovernment since 1992.(iii) Project Tiger, Project Rhino, Project Great Indian Bustard and many otherecodevelopmental projects have been introduced.(iv) 89 National Parks, 49 Wildlife sanctuaries and Zoological gardens are set up totake care of Natural heritage.