Class 9 Social Science Notes Chapter 5 (Natural vegetation and wild life) – Contemporary India Book

Alright class, let's delve into Chapter 5: Natural Vegetation and Wildlife. This is a crucial chapter, not just for understanding India's geography but also because questions frequently appear from this section in various government examinations. Pay close attention to the details, especially the distribution of flora and fauna, and the conservation efforts.

India's Biodiversity:

• India is one of the world's 12 mega biodiversity countries.
• It has about 47,000 plant species (making it 10th in the world and 4th in Asia in plant diversity).
  • This includes about 15,000 flowering plants (6% of the world's total).
  • Also includes non-flowering plants like ferns, algae, and fungi.
• India also has approximately 90,000 species of animals, including a rich variety of fish in its fresh and marine waters.
• Natural Vegetation (Virgin Vegetation): Refers to a plant community that has grown naturally without human aid and has been left undisturbed by humans for a long time.
  • Endemic Species: Plant species that are purely Indian in origin.
  • Exotic Species: Plants that have come from outside India.
• Flora: Term used to denote plants of a particular region or period.
• Fauna: Term used for species of animals.

Factors Affecting Flora and Fauna:

The huge diversity in flora and fauna kingdom is due to the following factors:

1. Relief:

   • Land: Affects natural vegetation directly and indirectly. Fertile land is generally devoted to agriculture, while undulating and rough terrains often have grasslands and woodlands, providing shelter to various wildlife.
   • Soil: Different types of soils support different types of vegetation. Sandy soils (desert) support cactus and thorny bushes, while wet, marshy, deltaic soils support mangroves and deltaic vegetation. Hill slopes with depth of soil have conical trees.

2. Climate:

   • Temperature: The character and extent of vegetation are mainly determined by temperature along with humidity, precipitation, and soil. On slopes of the Himalayas and hills of the Peninsula above 915m, the fall in temperature affects the types of vegetation and its growth (changes from tropical to subtropical, temperate, and alpine).
   • Photoperiod (Sunlight): Variation in duration of sunlight at different places is due to differences in latitude, altitude, season, and duration of the day. Longer sunlight duration aids faster growth (e.g., trees grow faster in summer).
   • Precipitation (Rainfall): Areas of heavy rainfall have denser vegetation compared to areas of less rainfall. The annual precipitation, including snowfall, largely determines the type of forest. The southwest monsoon (advancing monsoon, June to September) and northeast monsoon (retreating monsoon) bring most of the rain.

Importance of Forests (Ecosystem):

• Forests are renewable resources and play a major role in enhancing the quality of the environment.
• They modify local climate, control soil erosion, regulate stream flow.
• Support various industries (timber, paper, lac, medicinal plants).
• Provide livelihood for many communities.
• Offer panoramic or scenic views for recreation.
• Control wind force and temperature, causing rainfall.
• Provide humus to the soil and shelter to wildlife.
• India's natural vegetation has undergone significant changes due to demand for cultivated land, industrial development, urbanization, and overgrazing. The vegetation cover of India is no longer 'natural' in many parts, except inaccessible regions like the Himalayas, hilly region of central India, and the Marusthali (Thar desert).

Types of Vegetation in India:

Based on climatic conditions (especially rainfall), India's vegetation can be classified into the following major types:

1. Tropical Evergreen Forests (Tropical Rainforests):

   • Rainfall: Heavy rainfall areas (> 200 cm) with a short dry season.
   • Regions: Western Ghats (windward side), island groups of Lakshadweep, Andaman & Nicobar, upper parts of Assam, and Tamil Nadu coast.
   • Characteristics: Trees reach great heights (up to 60 m or above). Lush, multi-layered structure. No definite time for trees to shed leaves, so forests appear green all year round.
   • Flora: Ebony, mahogany, rosewood, rubber, cinchona.
   • Fauna: Elephants, monkeys, lemurs, deer, one-horned rhinoceros (Assam, West Bengal jungles), plenty of birds, bats, sloths, scorpions, snails.

2. Tropical Deciduous Forests (Monsoon Forests):

   • Characteristics: Most widespread forests in India. Trees shed their leaves for about six to eight weeks in the dry summer.
   • Rainfall: Between 70 cm and 200 cm.
   • Sub-types:
     • Moist Deciduous:
       • Rainfall: 100 cm to 200 cm.
       • Regions: Eastern parts of the country – northeastern states, along the foothills of the Himalayas, Jharkhand, West Odisha, Chhattisgarh, and eastern slopes of the Western Ghats.
       • Flora: Teak (most dominant), bamboos, sal, shisham, sandalwood, khair, kusum, arjun, mulberry.
     • Dry Deciduous:
       • Rainfall: 70 cm to 100 cm.
       • Regions: Rainier parts of the Peninsular plateau and the plains of Bihar and Uttar Pradesh. Large parts cleared for cultivation/grazing.
       • Flora: Teak, sal, peepal, neem.
   • Fauna (Common to both): Lion, tiger, pig, deer, elephant. Huge variety of birds, lizards, snakes, tortoises also found.

3. Tropical Thorn Forests and Scrubs:

   • Rainfall: Less than 70 cm.
   • Regions: North-western parts including semi-arid areas of Gujarat, Rajasthan, Madhya Pradesh, Chhattisgarh, Uttar Pradesh, and Haryana. Also found in interior, drier parts of the Deccan plateau.
   • Characteristics: Vegetation consists of thorny trees and bushes. Plants have long roots penetrating deep into the soil for moisture, thick and small leaves to minimize evaporation, and thorns.
   • Flora: Acacias, palms, euphorbias, cacti.
   • Fauna: Rats, mice, rabbits, fox, wolf, tiger, lion, wild ass, horses, camels.

4. Montane Forests (Mountain Forests):

   • Characteristics: Vegetation changes according to altitude due to decreasing temperature. Succession of natural vegetation belts similar to tropical to tundra region.
   • Altitudinal Zones:
     • Wet Temperate Type (1000-2000 m): Evergreen broad-leaf trees like oaks and chestnuts predominate. Found in higher hills of Northeast India and Southern India (Nilgiris, Anaimalai, Palani hills - called 'Sholas' here).
     • Temperate Forests (1500-3000 m): Coniferous trees like pine, deodar, silver fir, spruce, cedar. Found on southern slopes of Himalayas, high-altitude areas of southern and north-east India.
     • Alpine Vegetation (> 3600 m): Temperate forests and grasslands give way to Alpine vegetation. Silver fir, junipers, pines, birches are common. Progressively stunted growth as they approach the snow-line. Ultimately merge into Alpine grasslands used for grazing by nomadic tribes (Gujjars, Bakarwals). At higher altitudes, mosses and lichens form part of tundra vegetation.
   • Fauna: Kashmir stag (Hangul), spotted deer, wild sheep, jackrabbit, Tibetan antelope, yak, snow leopard, squirrels, shaggy horn wild ibex, bear, rare red panda, sheep and goats with thick hair.

5. Mangrove Forests (Tidal Forests):

   • Regions: Coasts influenced by tides. Mud and silt get accumulated. Found in deltas of Ganga, Mahanadi, Krishna, Godavari, Kaveri. Ganga-Brahmaputra delta has the largest extent, known as Sunderbans (named after Sundari tree). Also found in Andaman & Nicobar Islands and some other coastal areas.
   • Characteristics: Dense mangroves with roots submerged under water. Roots are adapted for survival in saline, waterlogged conditions (pneumatophores).
   • Flora: Sundari trees (provide durable hard timber), Palm, coconut, keora, agar.
   • Fauna: Royal Bengal Tiger (famous), turtles, crocodiles, gharials, various snakes.

Wildlife of India:

• Rich fauna with approx. 90,000 animal species, 2,000+ species of birds (13% of world's total), 2,546 species of fish (nearly 12% of world's stock). Also shares 5-8% of world's amphibians, reptiles, and mammals.
• Elephants: Found in hot wet forests of Assam, Karnataka, Kerala.
• One-horned Rhinoceroses: Live in swampy and marshy lands of Assam and West Bengal.
• Wild Ass and Camels: Found in arid areas of Rann of Kachchh (Gujarat) and Thar Desert (Rajasthan) respectively.
• Indian Bison (Gaur), Nilgai (Blue Bull), Chousingha (Four-horned antelope), Gazel, various species of Deer are other animals found. Several species of monkeys.
• India is the only country with both Tigers and Lions.
  • Gir Forest in Gujarat is the last remaining natural habitat of the Asiatic Lion.
  • Tigers are found in forests of Madhya Pradesh, the Sunderbans of West Bengal, and the Himalayan region.
• Leopards are also members of the cat family.
• Himalayan Region: Hardy animals adapted to extreme cold like Yak, shaggy-horned wild ox, Tibetan antelope (Bharal - blue sheep), wild sheep, Kiang (Tibetan wild ass). Ibex, bear, snow-leopard, rare red panda.
• Rivers, Lakes, Coastal areas: Turtles, crocodiles, gharials (only representative found in India).
• Birds: Peacocks, pheasants, ducks, parakeets, cranes, pigeons etc.

Conservation of Flora and Fauna:

• Threats: Hunting by greedy hunters for commercial purposes, pollution (chemical, industrial waste, acid deposits), introduction of alien species, reckless cutting of forests for cultivation and habitation (habitat destruction), overgrazing.
• Government Steps:
  1. Wildlife Protection Act: Implemented in 1972. Provides a legal framework for the protection of wild animals, birds, and plants.
  2. Biosphere Reserves: 18 biosphere reserves have been set up for conserving biodiversity. (Key ones mentioned in NCERT: Sunderbans (WB), Nanda Devi (Uttarakhand), Gulf of Mannar (TN), Nilgiris (TN, Kerala, Karnataka), Nokrek (Meghalaya), Great Nicobar, Manas (Assam), Simlipal (Odisha), Dihang-Dibang (Arunachal Pradesh), Dibru Saikhowa (Assam), Agasthyamalai (Kerala, TN), Kanchenjunga (Sikkim), Pachmarhi (MP), Achanakmar-Amarkantak (MP, Chhattisgarh), Kachchh (Gujarat - Largest), Cold Desert (HP), Seshachalam Hills (AP), Panna (MP)). Memorize this list and locations for exams.
  3. Financial and Technical Assistance: Provided to many Botanical Gardens since 1992.
  4. Project Tiger, Project Rhino, Project Great Indian Bustard and many other eco-developmental projects introduced.
  5. Establishment of 103 National Parks, 535 Wildlife Sanctuaries, and Zoological gardens to take care of natural heritage.
• Awareness: Crucial for conservation. Programs like Van Mahotsav encourage tree planting.

Remember, every species has a role to play in the ecosystem. Conservation is essential for maintaining ecological balance and preserving our rich natural heritage.

Multiple Choice Questions (MCQs):

1. Which type of forest is most widespread in India?
   a) Tropical Evergreen Forests
   b) Tropical Deciduous Forests
   c) Montane Forests
   d) Mangrove Forests

2. Ebony, Mahogany, and Rosewood trees are typically found in which type of vegetation zone?
   a) Tropical Thorn Forests and Scrubs
   b) Tropical Evergreen Forests
   c) Montane Forests
   d) Tropical Deciduous Forests

3. The Gir Forest in Gujarat is the last remaining habitat for which animal?
   a) Royal Bengal Tiger
   b) One-horned Rhinoceros
   c) Asiatic Lion
   d) Snow Leopard

4. In which state is the Simlipal Biosphere Reserve located?
   a) West Bengal
   b) Assam
   c) Odisha
   d) Meghalaya

5. Which of the following factors is LEAST influential on vegetation type at a specific location in India?
   a) Annual Rainfall
   b) Temperature Range
   c) Longitude
   d) Soil Type

6. Mangrove vegetation in India is predominantly found in:
   a) Himalayan foothills
   b) Arid regions of Rajasthan
   c) Deltas of major rivers
   d) Western Ghats slopes

7. The Wildlife Protection Act was implemented in India in which year?
   a) 1962
   b) 1972
   c) 1982
   d) 1992

8. Alpine vegetation, including mosses and lichens (Tundra type), is found in India at altitudes above:
   a) 1000 meters
   b) 2000 meters
   c) 3600 meters
   d) 5000 meters

9. Which tree species is characteristic of Mangrove forests and lends its name to the Sunderbans delta?
   a) Teak
   b) Sal
   c) Sundari
   d) Deodar

10. Which of the following is NOT a major threat to biodiversity in India?
    a) Afforestation drives
    b) Habitat destruction
    c) Poaching
    d) Introduction of alien species

Answer Key for MCQs:

1. b) Tropical Deciduous Forests
2. b) Tropical Evergreen Forests
3. c) Asiatic Lion
4. c) Odisha
5. c) Longitude (Latitude, Altitude, Climate factors like Rainfall/Temp, and Soil are more direct influences)
6. c) Deltas of major rivers
7. b) 1972
8. c) 3600 meters
9. c) Sundari
10. a) Afforestation drives (Afforestation is planting trees, which helps biodiversity)

Study these notes thoroughly. Focus on the distribution maps in your textbook, the names of species associated with each vegetation type, and the conservation measures, especially the Biosphere Reserves. Good luck with your preparation!