Long Answer Questions - Natural Vegetation and Wildlife

Q.1. Describe the major vegetation types found in the Himalayas.
 OR
 Why does mountain vegetation change with altitude ? Explain with example .  (CBSE 2010)

Ans: In mountainous regions, temperature, rainfall and soil change with altitude, so vegetation changes in a definite pattern from the foothills to the snowline. This results in a vertical succession of plant types. The major vegetation zones in the Himalayas may be described as follows:

• Foothills and lower slopes (up to about 1,000 metres). Here vegetation depends on rainfall: in very wet areas tropical evergreen trees such as rosewood, ebony and ironwood occur; in less wet areas tropical moist and dry deciduous trees like sal, teak, palas and bamboo are common.
• Wet temperate forests (about 1,000-2,000 metres). These forests have evergreen broad-leaved trees such as oaks and chestnut. They are dense and support a rich undergrowth.
• Temperate coniferous forests (about 1,500-3,000 metres). Softwood trees such as pine, deodar, silver fir, spruce and cedar dominate. These trees are well adapted to cooler conditions.
• Subalpine and alpine zone (above about 3,000-3,600 metres). Temperate forests give way to alpine vegetation: stunted trees (junipers, birches), shrubs and alpine grasslands. Trees become progressively low and stunted as the snowline is approached.
• Tundra type vegetation (near and above the snowline). Only hardy mosses, lichens and small shrubs survive in shaded or exposed sites close to permanent snow and ice.

Example: On one mountain slope you may find tropical deciduous trees in the lower foothills, oak forests higher up, pine and deodar in still higher belts, and alpine meadows and lichens close to the snowline. This change with height is mainly due to falling temperature and changing moisture and soil conditions with altitude.

Q.2. Describe how rainfall and relief influence the vegetation of an area.

Ans: Rainfall and relief are two important physical factors that determine the type, density and distribution of natural vegetation.

Rainfall :

• Amount and distribution of rainfall decide whether an area will have dense forests, grassland or scrub. Areas with heavy rainfall support dense forests; arid and semi-arid areas support thorny and scrub vegetation.
• Typical relations between rainfall and vegetation: more than 200 cm - tropical evergreen rainforests; 100-200 cm - tropical moist deciduous forests; 70-100 cm - tropical dry deciduous forests; less than 70 cm - thorny trees and bushes.

Relief :

• The shape of the land affects soil, drainage and microclimate and so influences vegetation. Fertile flat plains are often converted to agriculture, reducing natural vegetation.
• Hilly and undulating terrain often retains grasslands and woodlands because it is less suited to intensive farming.
• In mountainous areas vegetation changes with altitude - for example, different forest types occur on different heights of the Himalayas.

Combined effect (example): The windward slopes of the Western Ghats receive heavy rainfall and are covered with thick forests, while the leeward (eastern) slopes get less rain and have much sparser vegetation.

Q.3. Give a brief account about the wildlife of India.

Ans: India has a rich and varied wildlife. The country is home to about 89,000 animal species, some 1,200 species of birds and 2,500 species of marine and freshwater fish. India also contains 5-8 per cent of the world's amphibians, reptiles and mammals.

The main types of wildlife and representative examples are:

• Large carnivores: Tigers occur in many national parks and sanctuaries (for example in Madhya Pradesh, the Sunderbans and parts of the Himalaya).
• Big cats and lions: The Asiatic lion survives in the Gir forest of Gujarat - India is the only country with both lions and tigers.
• Elephants and rhinoceroses: Large Asian elephants are found in Assam, Karnataka and Kerala; the one-horned rhinoceros occurs in the swampy lands of Assam and West Bengal.
• Arid and high-altitude species: The Indian wild ass lives in the Rann of Kachchh and camels in the Thar desert. In Ladakh and high Himalaya live yak, bharal (blue sheep), ibex, snow leopard and the rare red panda in some areas.
• Ungulates and primates: Indian bison, nilgai, chousingha (four-horned antelope), gazelles, several deer species and many monkeys occur across different habitats.
• Birds and reptiles: A large variety of birds, including the peacock (national bird), are found in India. Turtles, crocodiles, gharials and many snake species live in rivers, lakes, coasts and forests.

Together these animals form rich ecosystems across India's forests, grasslands, wetlands and coastal areas.

Q.4. Why are some of the animals and plants endangered in India? How can they be protected? (Important)
 OR
 What steps have been taken by the government to protect flora and fauna of the country. (CBSE 2010)

OR
 Write three measures to protect wildlife.  (CBSE 2010)

OR
 Write any three measures to conserve ecosystem. (CBSE 2010)

Ans: Endangered species are those at risk of extinction. In India about 1,300 plant species are considered endangered, and several animals - for example the one-horned rhino, tiger, Indian wild ass, blackbuck, red panda, Asiatic elephant and the great Indian bustard - are threatened.

Main causes of endangerment :

• Hunting and poaching for illegal trade in tusks, horns, skins and other body parts.
• Destruction of natural habitats by clearing forests for cultivation, settlements and industries.
• Pollution from industrial and agricultural waste and acid deposition, which harm plants and animals.
• Introduction of alien species which compete with or prey upon native species.

Measures to protect flora and fauna :

• Protected areas: Establishment of national parks, wildlife sanctuaries, botanical gardens and protected forests - India has many such areas to conserve species in their natural habitats.
• Biosphere reserves: Fourteen biosphere reserves have been set up to conserve biodiversity and promote sustainable development.
• Conservation projects: Special projects such as Project Tiger, Project Rhino and programmes for the great Indian bustard target the protection and recovery of endangered species.
• Legal protection: Wildlife Protection Acts and strict laws against poaching and illegal trade help safeguard species.
• Community and awareness measures: Afforestation, public awareness campaigns, eco-development and involvement of local communities help reduce pressure on ecosystems.

Together these measures aim to reduce risks and promote long-term recovery of endangered plants and animals.

Q.5. Write a note on the formation and distribution of mangrove forests in India. (Important)
 OR
 Mention two regions in India where you will find mangrove forests. What are the features of the mangrove forests? (CBSE 2010)

Ans: Mangrove (tidal) forests develop in coastal and deltaic areas where riverine silt, tidal water and saline conditions create a special habitat. These forests are common where clayey soils and regular tidal inundation occur.

Features and adaptations:

• Mangrove plants are adapted to alternating fresh and saline water and to soft, waterlogged mud.
• They often have breathing roots or pneumatophores that project above water to take in air, and stilt-like roots that support the trunk in soft soil.
• Many species tolerate high salt content and unstable soils; these forests are dense and provide durable timber in some parts.

Typical species: Sundari (after which the Sunderbans are named), keora, agar, and palms and coconut in some areas.

Distribution in India :

• The Ganga-Brahmaputra delta - the Sunderbans are the largest mangrove tract and are dominated by sundari trees.
• Deltaic regions on the east coast - deltas of the Mahanadi, Godavari, Krishna and Kaveri rivers also support mangrove forests.

Mangroves are important for coastal protection, fisheries and biodiversity and need careful conservation.

Q.6. Write a note on the importance of biosphere reserve. What are its objectives?

Ans: Biosphere reserves are protected areas established to conserve biological diversity while promoting sustainable use and scientific research. They form part of a national and global network intended to demonstrate compatible links between conservation and development.

Importance:

• They help maintain ecological balance by protecting representative ecosystems of a region.
• They conserve a wide range of plant and animal species and their habitats, including endangered species.
• They provide sites for scientific research, education and monitoring of environmental changes.

Main objectives :

• To protect and conserve biological diversity, preserving plants and animals in their natural forms.
• To prevent over-exploitation of resources and protect flora and fauna from unsustainable use.
• To promote research, experimentation and training in forestry, ecology and conservation methods.
• To save endangered species and reduce the risk of extinction of valuable species.

India currently has fourteen biosphere reserves that combine conservation with local livelihoods and research activities.

Q.7. Give the main causes for depletion of biodiversity in India. (CBSE 2010)

Ans: Although India supports rich natural vegetation and wildlife because of its varied climate and landforms, only about 23 per cent of the land is currently under forests, which is below the 33 per cent target of the National Forest Policy. The main causes for the depletion of biodiversity are:

• Deforestation. Large tracts of forest have been cleared to meet the growing demand for farmland, for industrial sites and for human settlements.
• Shifting cultivation. Practised in certain hilly areas of the north-east and central India, this destroys forest cover when fallow periods are insufficient.
• Mining and construction. Mining operations clear vegetation, while dams and reservoirs submerge forests and alter habitats.
• Natural hazards and disasters. Forest fires, landslides, cyclones and events such as the 2004 tsunami have damaged vegetation in affected regions.
• Overgrazing and habitat loss. Excessive grazing by livestock and conversion of forests to other uses reduce plant diversity and fragment habitats.
• Local extinctions. Valuable rainforests in places such as the Andaman and Nicobar Islands have been severely reduced by human activities.

These human and natural factors together accelerate the loss of species and habitats in India.

Q.8. What type of dangers does the wildlife sanctuaries of India face? How can they be protected better? Write a brief note on each.

Ans: India has established 492 wildlife sanctuaries to protect its fauna, but these areas face several dangers that reduce their effectiveness. The main threats and measures to improve protection are:

Dangers:

• Poaching and illegal trade. Animals are hunted for their hides, tusks, horns and other parts for black market sale.
• Hunting for sport. Illegal hunting reduces populations of vulnerable species.
• Human-wildlife conflict. During floods or crop damage, animals may move into inhabited areas and are sometimes killed by villagers.
• Lack of trained staff and funds. Shortage of skilled personnel and inadequate funding lead to poor management and neglect of sick or injured animals.
• Encroachment and habitat loss. Illegal settlement, grazing and resource extraction inside sanctuaries degrade habitats.

Measures to improve protection:

• Strict vigilance and law enforcement. Regular patrolling, use of modern surveillance and strict punishment for poaching and encroachment reduce illegal activities.
• Clear boundaries and better management. Well-marked protected boundaries, adequate funding and trained staff improve sanctuary management.
• Community involvement and awareness. Educating local people, compensating for crop or livestock losses and involving communities in conservation reduce conflict.
• Capacity building and resources. Training wardens and staff, and providing veterinary care and sufficient funds, helps maintain healthy wildlife populations.
• Habitat restoration and coordination. Restoring degraded areas, creating buffer zones and coordinating with nearby protected areas improve long-term conservation.

Combining strict protection with community participation and adequate resources makes sanctuaries more effective in conserving India's wildlife.