forest resources

1. Lecture
on
Forest Resources
By
Ravi Gedela M.Tech IITG, (PhD IITG)
Assistant professor
Department of Bio-Sciences
RGUKT -SKLM
Rajiv Gandhi University of Knowledge
Technologies

2. Forest Resources
• Statute:
• India’s forests are currently governed by the National
Forest Policy, 1988 which has environmental balance and
livelihood at its centre.
• Forestry Report:
• According to India State of Forest Report, 2019, tree and
forest cover together made up 24.56% (8,07,276 sq km) of
India's area.
• The country is pursuing a long-term goal of having 33
percent of its land under forest cover.

5. Based on Average Annual Rainfall
• In India, the Forests, on the basis of average annual rainfall,
can be categorised broadly into five categories:
1. Tropical Evergreen Forests
2. Tropical Deciduous Forests (Monsoon Forests)
3. Thorn Forests
4. Montane Forests
5. Littoral/Swamp Forests

6. Indian Scenario
• In India forest cover Overall, 21.02% of the country's
geographical area is now under green cover
(as per 2009* data) The total forest cover in India is 6,90,899
km2
• Forest cover in India is defined as all lands, more than one
hectare in area with a tree canopy density of more than 10%.

7. 1.Tropical Evergreen Forests
• Moist Evergreen Forests:
• Region: Found in southern India along the Western Ghats, Andaman
and Nicobar Islands and north-eastern region.
• Climatic Conditions: Found in warm and humid areas with an annual
precipitation of over 200 cm and mean annual temperature above
22°C.
• Trees: In these forests, trees reach great heights up to 60 m or above.
• There is no definite time for trees to shed their leaves, flowering
and fruition; these forests appear green all the year round.
• Species found in these forests include Rosewood, Mahogany, Aini,
Ebony, etc.
• The more common trees that are found here are the jackfruit,
betel nut palm, jamun, mango…

8. • Semi Evergreen Forests:
• Region: Found in the less rainy parts of the regions where moist
evergreen forests are found; Western Ghats, Andaman and Nicobar
Islands, and the Eastern Himalayas.
• Trees: Such forests have a mixture of moist evergreen and moist
deciduous trees.
• The under growing climbers provide an evergreen character to
these forests.
• Main species are white cedar, hollock and kail.

9. • Dry evergreen:
• Region: Found in the Shivalik Hills and foothills of the Himalayas up
to a height of 1000 metres in the north.
• Found along Andhra Pradesh and Karnataka coast in the south.
• Climatic Conditions: Usually have a prolonged hot and dry season and
a cold winter.
• Trees: Have mainly hard-leaved evergreen trees with fragrant flowers,
along with a few deciduous trees.
• Trees have a varnished look.
• Some of the more common ones are the pomegranate, olive, and
oleander.

10. 2.Tropical Deciduous Forests (Monsoon
Forests)
• Moist Deciduous Forests:
• Region: These forests are found in the north-eastern states along
the foothills of Himalayas, eastern slopes of the Western
Ghats and Odisha.
• Rainfall: Found in the regions which record rainfall between 100-200
cm.
• Trees: Tall trees with broad, branched trunks.
• Some of the taller trees shed their leaves in the dry season.

11. • Dry Deciduous Forests:
• Region: Found throughout the northern part of the country except in
the north-east.
• Also found in Madhya Pradesh, Gujarat, Andhra Pradesh,
Karnataka, and Tamil Nadu.
• Rainfall: Covers vast areas of the country, where rainfall ranges
between 70 -100 cm.
• On the wetter margins, it has a transition to the moist deciduous,
while on the drier margins to thorn forests.
• Trees: As the dry season begins, the trees shed their leaves completely
and the forest appears like a vast grassland with naked trees all
around.

12. 3.Thorn Forests
• Rainfall: The forests occur in the areas that receive annual rainfall less
than 50cm.
• Regions: This type is found in areas with black soil: North, West, Central,
and South India.
• Includes semi-arid areas of south west Punjab, Haryana, Rajasthan,
Gujarat, Madhya Pradesh and Uttar Pradesh.
• Trees: The trees do not grow beyond 10 metres and consist of a variety of
grasses and shrubs. Spurge, caper, and cactus are typically found in this
region.
• The plants remain leafless for most part of the year.
• Babul, Acacia, Kokko, Khair, Khajuri, Ber, Neem, Khejri, Palas, etc.are
common species of the forests.

13. 4. Montane Forests
• Montane Wet Temperate Forests:
• Region: Occur in the northern and southern India.
• In the North, it is found in the region to the east of Nepal into
Arunachal Pradesh, at a height of 1800–3000 metres, receiving
a minimum rainfall of 200 cm.
• In the South, it is found in parts of the Nilgiri Hills, the higher
reaches of Kerala.
• Trees: The forests in the northern region are denser than in the South.
• This is because over time the original trees have been replaced by
fast-growing varieties such as the eucalyptus.
• Rhododendrons, Champa and a variety of ground flora can be
found here.

14. • Montane Subtropical Forests:
• Climatic Conditions: Found in the region where average rainfall is 100-
200 cm and temperature varies between 15°C to 22°C.
• Region: Found in north-western Himalayas (except Ladakh and
Kashmir), Himachal Pradesh, Uttarakhand, Sikkim and Arunachal
Pradesh.
• Trees: Chir (Pine) is the main tree but Oak, Jamun and Rhododendron
are also found in these forests.

15. • Himalayan Forests:
• Himalayan Moist Forests:
• Region: Found in Jammu & Kashmir, Himachal Pradesh,
Uttarakhand and northern hilly parts of Bengal.
• Elevation: Found in the belt where altitude varies between 1000-
2000 m.
• Trees: Oak, chestnut, chir, sal, shrubs and nutritious grasses.
• Himalayan Dry Temperate:
• Region: J&K, Chamba, Lahaul & Kinnaur districts (Himachal
Pradesh) and Sikkim.
• Trees: Mainly coniferous; deodar, oak, chilgoza, maple, olive,
mulberry and willow.

16. • Alpine and Subalpine Forests:
• Elevation: In the higher reaches, there is a transition to Alpine forests
and pastures occurring at altitudes of 2,500-4,000 m.
• Sub alpine forests extend from Kashmir to Arunachal Pradesh
between 2900 to 3500 metres.
• Trees: In the Western Himalayas, the vegetation consists mainly of
juniper, rhododendron, willow, and black currant.
• In the eastern parts, red fir, black juniper, birch, and larch are the
common trees.

17. 5.Littoral/Swamp Forests
• Region: Found along the Andaman and Nicobar Islands and the delta area
of the Ganga and the Brahmaputra.
• Other areas of significance are the Mahanadi, the Godavari and the
Krishna deltas.
• Trees: Some of these forests are dense and impenetrable. Only a limited
number of plants are found in these evergreen forests.
• They have roots that consist of soft tissue so that the plant can
breathe in the water.
• It consists mainly of whistling pines, mangrove dates, palms, and
bulletwood.
• Mangroves in India: In India, the mangrove forests spread over 6,740 sq.
km which is 7% of the world’s mangrove forests.
• The forests stabilise the shoreline and protect the coastal areas from
erosion.

18. Functions of Forests
• The functions of forest may broadly classified into following categories
• Protective Function
• Productive Function
• Regulative Function
• Accessory Function

19. Protective Functions
• Forest Provide protection against Soil erosion, Droughts, floods, noise,
radiations
Soil erosion Floods
Soil erosion Droughts

20. Productive Functions
• Forest Provide various products like, gum resins, medicines, honey,
pulp, bamboo, timber, and fruits

21. Accessory Function
• Forest provides aesthetics, habitat to various flora and fauna besides that
it also has an recreational value.

22. Ecological Importance or uses of Forests
• Regulation of global climate and temperature
• Forest play a crucial role in regulation of global climate and temperature
as forest cover absorb the solar radiations that would otherwise be
reflected back into the atmosphere by bare surface of the earth.
• Transpiration of plants increases the atmosphere humidity which affects
the rainfall, cools the atmosphere and thus regulate the hydrological cycle

23. Reduction of Global Warming
• The main green house gas co2 is used by forests for photosynthesis
process the forest act as a sink for co2 there by reducing the green
house effect due to co2

24. • Plants take carbon dioxide and water from their
environment.
• They use the energy they capture from the sun to carry on
a process known as photosynthesis which converts the
atoms in the carbon dioxide and water into sugar (glucose)
and oxygen.
• 6CO2 + 6H2O + energy → C6H12O6 + 6O2

25. Production of Oxygen
• During Photosynthesis process forest releases oxygen a very
important gas for human survival thereby are called as lungs of
earth.

26. Absorption of Noise
• Forest cover absorbs the noise and helps in preventing noise
pollution

27. Absorption of air pollutants
• Forest absorbs many toxic gasses and air pollutants and can
help in keeping air pure.

28. Economical Importance of Forest
• Timber: Wood used for commercial purposes like for
making furniture and other items like boats, bridges
and other day to day uses.
• Fuel Wood: The wood is used as fuel for cooking and
other purposes by poor people.
• Raw material for wood based industries: forest
provide raw material for various wood based
industries like paper and pulp, sports goods,
furniture, match boxes etc.

29. • Food: Fruits, roots, leaves of plants and trees along with the meat
of forest animals provide the food to the tribal people.
• Miscellaneous Products: Miscellaneous products like, resin, gums,
oils, medicines, honey are provided by forests

30. Deforestation
• Forest are exploited since early times for humans to meet human
demand
• The permanent destruction of forest is called deforestation

31. Causes of Deforestation
• Population explosion: Population
explosion is the root cause of all the
environmental problems, vast area of
forests are cleared for human
settlement.
• Shifting Cultivation: It is a traditional
agroforestry system widely practiced in
north eastern region of country in
which felling and burning of forests
followed by cultivation of crop for few
years and abandon of cultivation allow
forests for re-growth cause extreme
damage to forest.

32. • Growing food demand: To meet the food
demand of rapidly growing population more
and more forests are cleared off for
agricultural purpose.
• Fire wood: Increasing demand of wood for
fuel increases pressure on forests.
• Raw material for wood based industry:
Increasing demand of wood for making furniture,
plywood, match box etc results into tremendous
pressure on forests.

33. • Infrastructure development: Massive
destruction of forest occurs for various
infrastructure development like, big
dams, highways projects etc.
• Forest fires: Forest fires may be natural
or man made cause a huge loss of forest
• Over grazing: Overgrazing of land by
cattle result into soil erosion,
desertification.
• Natural forces: Floods, storms, heavy
winds, snow, lightening are some of the
natural forces

34. Effects of Deforestation
• Deforestation adversely affects and
damages the environment
• The adverse effect of deforestation are
discussed below:
• Soil erosion: The soil gets washed away
with rain water on sloppy areas in the
absence of trees leading to soil erosion.
• Expansion of deserts: Due to strong
winds laden by rock dust, land mass
gradually gets converted in atmosphere.

35. • Decrease in rainfall : In the absence of
forest, rainfall declines considerably
because forest bring rains due to high rate
of transpiration. It maintains humidity in
atmosphere
• Loss of fertile land: Less rainfall results into
loss of fertile land owing to less natural
vegetation growth.
• Effect on climate: Deforestation induces
global climate change. Climate becomes
warmer due to lack of humidity in
deforested areas, also pattern of rainfall
changes

36. • Lowering of Water table: Lack of recharging
of underground reservoir, results into
lowering of water table
• Economic Losses: Deforestation will cause
loss of industrial timber and non timber
products
• Loss of biodiversity: Loss of flora and fauna
result into loss of bio-diversity leading to
disturbance in ecological balance world wide.
• Environmental changes: It will lead to
increase in carbon dioxide concentration and
other pollutants which results in Global
warming.

37. Afforestation
• The conservation measure against the
deforestation is afforestation. The
development of forest by planting trees
on waste land is called a forestation
The main objective of a forestation
• To control the deforestation
• To prevent soil erosion
• To regulate rainfall and maintain
temperature

38. • To control atmospheric condition by keeping it clean
• To promote planned uses of wasteland
• To Protect forest ecosystem and to get benefits of forest
products.

39. Forest Degradation in India
• At the beginning of 20th century about 30 % of land in India
was covered with forests but by the end of 20th century the
forest cover was reduced to 19.4%
• As a result of exploitation, the tropical forest cover in India, is
now only reduced to coastal western Ghats and northern
India
• We have a huge population size and a very low precipitate
forest area 0.075 Ha per capita as compared to 0.64 ha/
capita of world forest area

40. • The National forest policy has recommended 33 % forest area for
plains and 67 % for hills
• The deforestation rate per unit population in India is lowest among
the major tropical countries
• For effective forest management of country we have to take the
confidence of tribal who have been living in forest.

41. Thank you