Natural Vegetation

Natural vegetation refers to the plant community which has grown naturally without any human assistance and has not been disturbed over a long time, so as to allow its individual species to adjust themselves fully to the climate and soil conditions.

(i) Evergreen forests are found in areas of high temperature, having high annual rainfall. Western Ghats receive more than 200 cms. of annual rainfall with an average annual temperature between 25°C and 27°C. Similarly, deciduous forests are found in areas with moderate rainfall and the eastern ghats receive annual rainfall between 100 cm and 200 cm with mean annual temperature range of 24°C and 27°C. Hence, the Western Ghats are covered with thick evergreen forests while the Eastern Ghats are coven by deciduous forests.

(ii) Tropical evergreen forests have tall trees as this region remains warm and wet throughout the year. Since the trees do not have a fixed time to shed their leaves, to flower or for fruition, the forest appears green all the year round.

(iii) Deciduous forests are commercially most exploited because besides providing valuable timber, they provide various other valuable products, like sandalwood, which are in great demand in India and abroad. Moreover, they are less dense which makes transport between these forests and markets easier and economical.

(i) Tropical rain forests are found on the western slopes of the Western Ghats.

(ii) Two main characteristics of tropical rain forests are-

1. Trees reach great heights of more than 60 m.
2. Since this region remains warm and wet throughout the year, it has a luxuriant vegetation of all kinds- trees, shrubs and creepers which give it a multi-layered structure.

The climatic conditions under which Tropical Evergreen Forests develop are-

1. Annual rainfall of more than 200 cm
2. Average annual temperature between 25°C and 27°C
3. Average annual humidity exceeds 77 percent

(i) Tropical Evergreen Forests are difficult to exploit for commercial purposes because of the tangled mass of canes, palms, bamboos, ferns and climbers along with the lack of means of transport.

(ii) Delta area of river Ganga is called Sunderbans because the forests in this area have sundari trees.

(iii) Forests are grown in and around the cities having Iron and Steel Industries, and Thermal Power Plants because the level of pollution is much higher in areas where industries are located and forests prevent pollution and act as a barrier for the dust and purify the air.

(i) The characteristic features of deciduous forests are-

1. The trees in these forests shed their leaves from six to eight weeks during spring and early summer.
2. A particular species can be found over a large area.
3. They are commercially most exploited.

(ii) The two types of deciduous forests are-

1. Moist Deciduous Forests
2. Dry Deciduous Forests

Tropical Desert Vegetation thrives in south-western Punjab, Haryana, Uttar Pradesh, central and eastern Rajasthan, Madhya Pradesh, Chhattisgarh, Gujarat, parts of Maharashtra, Karnataka and Andhra Pradesh.

These forests thrive in areas where temperature remains between 26°C to 29°C and the rainfall is not more than 200 cm.

(i) The forest area has greatly depleted in India as forests have been cleared for the purpose of cultivation. Timber has become an important commercial resource. Rapid industrialization, urbanisation and expansion of cities has also led to the destruction of forest cover in the country.

(ii) The Tropical Evergreen forests are found on the western slope of the Western Ghats because evergreen forests are found in areas of high temperature and high annual rainfall. Western Ghats receive more than 200 cms. of annual rainfall with an average annual temperature between 25°C and 27°C.

(iii) Acacia has long roots so that the roots can reach deep, ground water resources and therefore, survive drought like conditions.

(i) Two characteristic features of tropical desert vegetation are-

1. These forests have Xerophytic vegetation. Due to paucity of rainfall, the trees are stunted with large patches of coarse grasses.
2. Plants remain leafless for most part of the year and look like scrub vegetation.

Two typical trees found here are babool and date palm.

(ii) Tropical deserts have stunted trees due to paucity of rainfall.

Man has been overexploiting the forests to satisfy not only his needs but also his greed. This has led to a decline in the forest cover.

1. Due to rapid population growth and the demand for more food, forests have been cleared to convert them into agricultural land.
2. Forests have been converted into pasture land for expanding dairy farming and cattle ranching.
3. Overgrazing in the forests by animals in the tropical and sub-tropical regions has resulted into large-scale degradation of natural vegetation.
4. Ever increasing demand for timber for various purposes due to industrial expansion and urbanisation has added to the problem of deforestation.
5. Construction of multi-purpose river valley projects has led to submergence of land and destruction of forested riversides.

All these factors have led to the decline in forests.

A successful community-based conservation initiative in India focused on preserving natural vegetation is the Chipko Movement.

The Chipko Movement, which began in the 1970s in the Himalayan region of Uttarakhand, was a grassroots environmental movement aimed at preventing deforestation and promoting sustainable forest management. Local villagers, especially women, played a crucial role in this movement by hugging trees to prevent them from being cut down by logging companies. This initiative not only helped in conserving forests but also raised awareness about the importance of trees in maintaining ecological balance.

The movement's success led to a ban on tree-felling in the Himalayan region for 15 years and influenced future environmental policies in India.

The characteristic features of mangrove vegetation are as follows:

1. Salt-Tolerant: Mangroves are adapted to survive in saline conditions where freshwater and seawater mix. They are halophytic, meaning they can tolerate high salt concentrations.

2. Specialized Root System: Mangroves have unique root systems such as aerial roots (pneumatophores) that rise above the soil to get oxygen in waterlogged and anaerobic conditions. Some species also have buttress roots that provide stability in soft, muddy soil.

3. Adaptation to Waterlogging: The roots of mangroves are adapted to thrive in waterlogged, muddy soil, making them effective in holding the coastal soil together and preventing erosion.

4. Salt Excretion: Some mangrove species can excrete excess salt through their leaves, while others store it in their tissues to prevent damage.

6. Provides Habitat: Mangroves support a diverse ecosystem by providing habitat for a wide range of animals, including fish, crabs, mollusks, and birds, and act as breeding grounds for marine life.

7. Protects Coastlines: Mangroves act as a natural barrier against storm surges, tidal waves, and coastal erosion, protecting the coastal areas from the impact of storms and high waves.

Environment determines the natural vegetation of a place depending on variations in climatic conditions, soil types and relief features.

Tidal forests are one of the most specialised tropical natural vegetation types. India has a variety of wetlands habitats. These lands are between terrestrial and aquatic system where the water table is usually at or near the surface of land.

Two typical trees found here are Keora and Amur.

Tropical Evergreen forests are found in the western part of the Western Ghats. They are named so because they remain green throughout the year as they do not have any particular season to shed their leaves and also because they grow in the regions receiving annual rainfall of more than 200 cm.

(i) Forests constitute an important natural resource because trees provide us with products such as fruits, leaves, roots and tubers of plants. Wood is used for making furniture and as a source of energy. Wood and bamboo pulp is used to make paper. Forests also provide fibers, essential oils, edible plants etc.

(ii) Corridors are established between different reserved forests to allow the migration of wild animals. This will also help numerous species of animals to use these corridors for their dispersal and migration.

(iii) Tidal forests have profuse growth with tangle of climbers to survive in soft and shifting mud.

(i) Afforestation means planting trees on lands which are not previously covered with forest vegetation.

(ii) To conserve forests, we can use non-conventional or renewable sources of energy like solar energy, tidal energy, hydel energy etc.

Social forestry refers to the management and protection of forests and afforestation on barren lands with the purpose of helping in the environmental, social and rural development.

Three methods for the conservation and development of forests in India are-

1. Increasing the area under forests
2. Afforestation around industrial units
3. Using alternative sources of energy

Three objectives of agro-forestry are-

1. To reduce pressure on natural forests for obtaining timber as well as non-timber forest produce.
2. To check soil erosion and to maintain the natural fertility of the soil.
3. To maintain ecological balance along with proper utilisation of farm resources.

The vegetation in the Himalayas vary with altitude because in the mountain regions, temperature decreases with altitude.

Tropical Evergreen forests appear dark inside the forests because of the dense canopy of trees which do not allow enough sunlight to reach the ground.

(i) In mountain regions, temperature decreases with increase in altitude. This has a corresponding effect on the natural vegetation of the mountain region. Thus, vegetation in lower regions of Nilgiri is sub tropical and vegetation in upper regions of Nilgiri is temperate.

(ii) Sundari trees are used for boat making and construction purposes because these trees provide hard durable timber.

(iii) Littoral forest is also called tidal forest because they are found in tidal zone, an area that is above water at low tide and under water at high tide.

I would choose agro-forestry over traditional forestry because it aims to provide conservation of the land and its improvement in order to achieve a combined produce of forest and agricultural crops.

Tropical deciduous vegetation is found in north-eastern part of the peninsula and along the foothills of the Himalayas.

Since coniferous trees are found in cold regions, they are well adapted to the cold climate. Their leaves are conical in shape so that the snow slides off easily from the branches without causing any damage to them.

(i) Littoral forest vegetation has breathing roots because these root enable the plants to breathe during the waterlogged conditions which occur when high tide comes.

(ii) Forests are compared to human lungs as the trees which make up a forest act as the compartment of lungs which help in inhalation and exhalation of the air. But in lungs, Oxygen is taken in and Carbon dioxide is given out whereas in trees carbon dioxide is inhaled and oxygen is exhaled.

(iii) Van Mahotsav is celebrated in our country every year to create awareness about the importance of trees and encourage community participation in planting trees.

Farm forestry is the practice of growing trees on the farm land to produce saleable products like timber, tannin, charcoal, etc. and to provide shade and shelter for stock and crops.
Two advantages of farm forestry are-

1. It increases farm income.
2. It supports community development.

All of the above

Flora

Vegetation

All of the above.

Monsoon forests

A is false but R is true.

Explanation — The acacia or babool trees have developed long tap roots that can reach deep, ground water resources and therefore, can survive drought like conditions.

The Moist Deciduous forests

Xerophytic

All of the above

To adapt themselves to survive in soft and shifting mud in wet marshy areas and river deltas.

Littoral

Hard durable timber for construction purposes and boat making.

social forestry