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| Class 9th Chapters | ||
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| 1. India – Size And Location | 2. Physical Features Of India | 3. Drainage |
| 4. Climate | 5. Natural Vegetation And Wildlife | 6. Population |
Chapter 5 Natural Vegetation And Wildlife
India is a country with immense **biodiversity**. Observing the plant and animal life even within a local area like a school's surroundings can reveal variations. Given India's vast geographical size and varied climate and terrain, the types of bio-forms found across the country are incredibly diverse.
India is recognised as one of the **12 mega bio-diversity countries** globally. It ranks tenth worldwide and fourth in Asia in terms of plant diversity, with approximately 47,000 plant species. Among these, about 15,000 are flowering plants, accounting for 6% of the world's total flowering plant species. India also hosts many non-flowering plants (ferns, algae, fungi) and boasts around 90,000 species of animals, including a rich variety of fish in its freshwater and marine environments.
**Natural vegetation** refers to a community of plants that has grown spontaneously without human intervention and has remained undisturbed by humans for a considerable period. This is called **virgin vegetation**. Cultivated crops, fruits, and orchards are part of vegetation but are not considered natural vegetation.
**Endemic or indigenous species** are those plant species that are native and found purely in India. **Exotic plants** are those that have originated from outside India.
The term **flora** is used to denote all the plants of a particular region or geological period, while **fauna** refers to all the animal species of a specific region or time.
Types Of Vegetation
Based on climatic conditions, particularly rainfall and temperature, India's natural vegetation can be classified into five major types (Figure 5.4):
- Tropical Evergreen Forests
- Tropical Deciduous Forests
- Tropical Thorn Forests and Scrubs
- Montane Forests
- Mangrove Forests
Figure 5.4 is a map illustrating the geographical distribution of the different types of natural vegetation found in India. The map uses different colours or patterns to show where Tropical Evergreen, Tropical Deciduous, Thorn Forests, Montane, and Mangrove forests are located across the country, correlating with climatic zones.
Tropical Evergreen Forests
These forests are found in areas receiving **heavy rainfall** (more than 200 cm annually) with a short dry season. They are predominantly located in the Western Ghats (receiving high rainfall), the island groups of Lakshadweep and Andaman and Nicobar, the upper parts of Assam, and the Tamil Nadu coast (receiving rain from the retreating monsoon).
Characteristics of Tropical Evergreen Forests:
- Trees reach great heights, up to 60 metres or more.
- The region's warm and wet climate throughout the year supports **luxuriant vegetation** with trees, shrubs, and creepers, creating a **multilayered structure**.
- Trees do not shed their leaves simultaneously at a particular time. This is why these forests remain **green throughout the year**.
Figure 5.1 is a photo illustrating a Tropical Evergreen Forest, known for its dense, multi-layered vegetation and the fact that trees remain green throughout the year, characteristic of regions with heavy rainfall and no distinct dry season.
Commercially important trees found in these forests include **ebony, mahogany, rosewood, rubber, and cinchona**. Animals commonly found are elephants, monkeys, lemurs, and deer. One-horned rhinoceroses inhabit the marshy jungles of Assam and West Bengal. These forests also host numerous birds, bats, sloths, scorpions, and snails.
Tropical Deciduous Forests
These are the **most widespread forests in India** and are also known as **monsoon forests**. They are found in regions receiving rainfall between **200 cm and 70 cm**. Trees in these forests shed their leaves for about six to eight weeks during the dry summer season.
Based on water availability, Tropical Deciduous Forests are divided into two types:
- **Moist Deciduous Forests:** Found in areas with rainfall between 200 and 100 cm. They are primarily located in the eastern parts of the country: northeastern states, along the Himalayan foothills, Jharkhand, West Odisha, Chhattisgarh, and the eastern slopes of the Western Ghats. **Teak** is the most dominant tree species. Other commercially important species include bamboos, sal, shisham, sandalwood, khair, kusum, arjun, and mulberry.
- **Dry Deciduous Forests:** Found in areas with rainfall between 100 cm and 70 cm. These forests occur in the rainier parts of the Peninsular plateau and the plains of Bihar and Uttar Pradesh. They are characterised by open stretches with trees like teak, sal, peepal, and neem. A significant portion of these forests has been cleared for cultivation or is used for grazing.
Figure 5.2 is a photo illustrating a Tropical Deciduous Forest, which sheds its leaves during the dry season, giving it a less dense appearance compared to evergreen forests. These are the most common type of forests in India, adapted to monsoon climate with a dry period.
Common animals found in these forests include lions, tigers, pigs, deer, and elephants. A wide variety of birds, lizards, snakes, and tortoises are also present.
The Thorn Forests And Scrubs
In regions receiving **less than 70 cm of rainfall**, the natural vegetation consists primarily of **thorny trees and bushes**. This type of vegetation is found in the **north-western parts of the country**, including the semi-arid areas of Gujarat, Rajasthan, Madhya Pradesh, Chhattisgarh, Uttar Pradesh, and Haryana.
Main plant species include **acacias, palms, euphorbias, and cacti**. Trees are scattered, and plants in these arid regions have adaptations to conserve water:
- **Long roots** that penetrate deep into the soil to access moisture.
- **Succulent stems** that store water.
- **Thick and small leaves** (or thorns) to minimise water loss through evaporation.
Figure 5.3 shows a photo illustrating Thorn Forests and Scrubs, typical vegetation in low-rainfall areas. These plants are characterised by thorns, small leaves, and scattered growth, adaptations for survival in arid conditions.
Common animals found in these forests include rats, mice, rabbits, foxes, wolves, tigers, lions, wild asses, horses, and camels.
Montane Forests
**Montane Forests** are found in **mountainous areas**. The decrease in temperature with increasing altitude leads to changes in natural vegetation, creating distinct belts of vegetation as one ascends a mountain, similar to the changes observed from tropical to tundra regions with increasing latitude.
Different vegetation belts are found at various altitudes:
- **Wet Temperate Forests (1000-2000 metres):** Predominated by evergreen broad-leaf trees like oaks and chestnuts.
- **Temperate Forests (1500-3000 metres):** Contain coniferous trees like pine, deodar, silver fir, spruce, and cedar. These forests cover southern Himalayan slopes and high-altitude areas in southern and northeastern India. Temperate grasslands are also common at higher elevations within this range.
- **Alpine Vegetation (Above 3600 metres):** Temperate forests and grasslands give way to Alpine vegetation. Trees like silver fir, junipers, pines, and birches are found, but they become progressively stunted towards the snow-line. They eventually merge into Alpine grasslands, used for grazing by nomadic tribes like the Gujjars and Bakarwals. At very high altitudes, mosses and lichens form part of the tundra vegetation.
Figure 5.5 is a photo illustrating Montane Forests, showing vegetation belts that change with increasing altitude, typically featuring coniferous trees at higher elevations, adapting to cooler temperatures and distinct rainfall patterns in mountainous regions.
Animals found in Montane forests include Kashmir stag, spotted deer, wild sheep, jack rabbits, Tibetan antelopes, yaks, snow leopards, squirrels, Shaggy horn wild ibex, bears, rare red pandas, and sheep and goats with thick hair adapted to cold climates.
Mangrove Forests
**Mangrove tidal forests** are found in coastal areas that are influenced by **tides**, where mud and silt accumulate. Dense mangrove trees are the characteristic vegetation, with their roots submerged under water. These forests are typically found in the deltas formed by major rivers like the **Ganga, Mahanadi, Krishna, Godavari, and Kaveri**.
In the Ganga-Brahmaputra delta, the **sundari trees** are common, providing durable hard timber. Other trees like palm, coconut, keora, and agar also grow in parts of the delta. The **Royal Bengal Tiger** is a famous animal species inhabiting these forests, along with turtles, crocodiles, gharials, and snakes.
Figure 5.6 shows a photo illustrating Mangrove Forests, characterised by trees with roots adapted to saline, tidal conditions and submerged under water, typically found in river deltas and coastal areas influenced by tides.
Plants and animals are essential for the ecosystem and human survival. Biodiversity is necessary for maintaining ecological balance and providing resources, hence conservation is vital. The loss of biodiversity due to human activities like exploitation and habitat destruction can lead to ecological imbalances.
Identifying the type of forest in a picture would involve looking for characteristics like tree density, leaf type (broadleaf, coniferous), shedding pattern (evergreen, deciduous), and ground vegetation, then comparing it to the descriptions of different forest types to determine similarities and dissimilarities with vegetation in one's own region.
India has a rich tradition of using herbs and spices for medicinal purposes. Ayurveda describes numerous plants with medicinal properties. Many of these plants are still in regular use today, although some are threatened or endangered.
Examples of commonly used medicinal plants in India include Sarpagandha (for blood pressure), Jamun (for digestion, diabetes), Arjun (for earache, blood pressure), Babool (for eye sores, tonic), Neem (antibiotic, antibacterial), Tulsi (for cough/cold), and Kachnar (for asthma, ulcers, digestive problems). Identifying medicinal plants in one's local area involves observing native flora and learning from local knowledge about their uses.
Source: Medicinal Plants by Dr. S.K. Jain provides a reference for studying medicinal plants.
Wildlife
India's fauna is as diverse as its flora, hosting approximately 90,000 animal species. This includes about 2,000 bird species (13% of the world's total), 2,546 fish species (nearly 12% of the world's stock), and between 5% and 8% of the world's amphibians, reptiles, and mammals.
Significant wildlife species in India include:
- **Elephants:** Found in the hot wet forests of Assam, Karnataka, and Kerala, known for their majestic presence.
- **One-horned rhinoceroses:** Inhabit swampy and marshy lands of Assam and West Bengal.
- **Wild ass and camels:** Adapted to the arid areas of the Rann of Kachchh and the Thar Desert.
- Other mammals: Indian bison, nilgai (blue bull), chousingha (four-horned antelope), gazelles, and various species of deer and monkeys.
- **Lions and tigers:** India is unique in having both. The natural habitat of the Indian lion is the **Gir Forest in Gujarat** (the last remaining habitat of the Asiatic lion). Tigers are found in forests of Madhya Pradesh, the Sundarbans of West Bengal, and the Himalayan region. Leopards are also members of the cat family and important predators.
- Aquatic life: Turtles, crocodiles, and gharials (the only living representative of a specific crocodile variety) are found in rivers, lakes, and coastal areas.
- Birdlife: Colourful and varied, including peacocks, pheasants, ducks, parakeets, cranes, and pigeons, found in forests and wetlands.
The Himalayas are home to animals adapted to extreme cold, such as the yak, Tibetan antelope, bharal (blue sheep), wild sheep, kiang (Tibetan wild ass), ibex, bear, snow-leopard, and red panda in specific high-altitude pockets.
Human activities have heavily exploited plant and animal resources, disrupting the ecosystem. Causes for the major threat to nature and biodiversity include:
- **Hunting by greedy hunters** for commercial purposes (poaching).
- **Pollution** from chemical and industrial waste, acid deposits.
- Introduction of **alien species** that outcompete native ones.
- Reckless **cutting of forests** for cultivation and habitation (habitat destruction).
As a result, many plant species (around 1,300) are endangered, and some (20) are extinct. Numerous animal species are also endangered or have become extinct.
The **Wildlife Protection Act was implemented in India in 1972** to protect flora and fauna.
To protect the country's flora and fauna, the government has taken several steps:
- **Biosphere Reserves:** Eighteen biosphere reserves have been established to protect ecosystems and genetic diversity. Twelve of these (Sundarbans, Nanda Devi, Gulf of Mannar, Nilgiri, Nokrek, Great Nicobar, Simlipal, Pachmarhi, Achanakmar-Amarkantak, Agasthyamalai, Kangchendzonga, Panna) are included in the World Network of Biosphere Reserves.
- **Botanical Gardens:** Financial and technical assistance is provided to many botanical gardens since 1992 to support plant conservation.
- **Eco-developmental Projects:** Projects like Project Tiger, Project Rhino, and Project Great Indian Bustard have been introduced to protect specific endangered species and their habitats.
- **National Parks, Wildlife Sanctuaries, and Zoological Gardens:** 106 National Parks, 573 Wildlife Sanctuaries, and Zoological gardens have been set up as protected areas to conserve natural heritage (as per Wildlife Institute of India data).
Figure 5.7 is a map illustrating the location of various Wildlife Reserves in India, including National Parks, Wildlife Sanctuaries, and Bird Sanctuaries. These protected areas are crucial for the conservation of India's diverse flora and fauna.
**Migratory birds**, like the Siberian Crane, visit some Indian wetlands (e.g., Rann of Kachchh) during winter. The Rann of Kachchh, where desert meets sea, is known for flamingos nesting in large numbers, an extraordinary sight and part of India's natural heritage.
The value of biodiversity is immense, providing edible and medicinal plants, domesticated animals for milk, transport, meat, and eggs, fish for food, and insects crucial for pollination and biological control in ecosystems. Every species plays a role in the ecosystem's balance, making conservation essential.
It is crucial to recognise the importance of the natural ecosystem for human survival and immediately stop the indiscriminate destruction of the natural environment. All citizens must realise this and contribute to conservation efforts.
**Bio-reserves:** Areas set aside to protect ecological integrity and demonstrate the relationship between conservation and development, linked through a global network. Examples: Nilgiri Biosphere Reserve, Nanda Devi Biosphere Reserve.
**Animals in Tropical Vegetation:** Elephant, tiger, lion, monkey, deer, rhinoceros. **Animals in Montane Vegetation:** Snow leopard, yak, wild sheep, bear, red panda, Kashmir stag.
**Flora:** All plants of a region or period. **Fauna:** All animals of a region or period.
**Tropical Evergreen:** Found in high rainfall areas (Western Ghats, islands), dense, multi-layered, green year-round as trees shed leaves at different times. **Deciduous forests:** Most widespread, found in monsoon areas (70-200cm rain), shed leaves in dry summer, divided into moist and dry deciduous.
Different types of vegetation in India: Tropical Evergreen, Tropical Deciduous (Moist and Dry), Tropical Thorn Forests & Scrubs, Montane, Mangrove. Vegetation of high altitudes (Montane) changes with altitude: Wet Temperate (oaks, chestnuts), Temperate (coniferous like pine, fir), Alpine (silver fir, junipers, pines, birches progressively stunted), Tundra (mosses, lichens) at highest altitudes.
Many species are endangered due to habitat destruction (deforestation, clearing for agriculture/habitation, pollution), over-exploitation/hunting (poaching), introduction of alien species, and environmental degradation (industrial waste, acid deposits).
India has a rich heritage of flora and fauna due to its diverse **climate and physiography**. The varied physical features (mountains, plains, deserts, plateaus, coasts, islands) create a wide range of habitats. The distinct climatic zones (tropical, subtropical, arid, alpine) support different types of vegetation and animal life, resulting in high biodiversity.