Terrestrial Ecosystems

Terrestrial ecosystems are exclusively land-based

ecosystems.
There are different types of terrestrial ecosystems
distributed around various geological zones.
They are as follows:
1. Forest Ecosystems
2. Grassland Ecosystems
3. Tundra Ecosystems
4. Desert Ecosystem Instagram
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Tundra Biome
• Tundra is the coldest of all the biomes.
• Tundra comes from the Finnish word tunturia, meaning treeless plain.
• It is noted for its frost-molded landscapes, extremely low
temperatures, little precipitation, poor nutrients, and short growing
seasons.

• Dead organic material functions as a nutrient pool.

• The two major nutrients are nitrogen and phosphorus. Nitrogen is
created by biological fixation, and phosphorus is created by
precipitation.

• Tundra is separated into two types:

• arctic tundra and
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• alpine tundra. @tireless.study
Characteristics of Tundra
1. Extremely cold climate
2. Low biotic diversity
3. Simple vegetation structure
4. Limitation of drainage
5. Short season of growth and reproduction
6. Energy and nutrients in the form of dead organic
material
7. Large population oscillations
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Artic Tundra
• Arctic tundra is located in the northern hemisphere,
encircling the north pole and extending south to the
coniferous forests of the taiga.
• The arctic is known for its cold, desert-like conditions.
• The growing season ranges from 50 to 60 days.
• The average winter temperature is -34° C (-30° F), but
the average summer temperature is 3-12° C (37-54° F)
which enables this biome to sustain life.
• Rainfall may vary in different regions of the arctic.
• Yearly precipitation, including melting snow, is 15 to 25
cm (6 to 10 inches). Soil is formed slowly. Instagram
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• A layer of permanently frozen subsoil
called permafrost exists, consisting mostly of gravel
and finer material.
• When water saturates the upper surface, bogs and
ponds may form, providing moisture for plants.
• There are no deep root systems in the vegetation of
the arctic tundra, however, there are still a wide
variety of plants that are able to resist the cold
climate.
• There are about 1,700 kinds of plants in the arctic
and subarctic, and these include shrubs, sedges,
reindeer mosses, liverworts, and grasses, 400
varieties of flowers, crustose and foliose lichen.
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• All of the plants are adapted to sweeping
winds and disturbances of the soil.
• Plants are short and group together to resist
the cold temperatures and are protected by the
snow during the winter.
• They can carry out photosynthesis at low
temperatures and low light intensities.
• The growing seasons are short and most
plants reproduce by budding and division
rather than sexually by flowering.
• The fauna in the arctic is also diverse: Instagram
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1. Herbivorous mammals: lemmings, voles, caribou, arctic hares and
squirrels

2. Carnivorous mammals: arctic foxes, wolves, and polar bears

3. Migratory birds: ravens, snow buntings, falcons, loons, ravens,

sandpipers, terns, snow birds, and various species of gulls

4. Insects: mosquitoes, flies, moths, grasshoppers, blackflies and arctic

bumble bees

5. Fish: cod, flatfish, salmon, and trout

Animals are adapted to handle long, cold winters and to breed and raise
young quickly in the summer. Animals such as mammals and birds also have
additional insulation from fat. Many animals hibernate during the winter
because food is not abundant. Another alternative is to migrate south in the
winter, like birds do. Reptiles and amphibians are few or absent because of
the extremely cold temperatures. Because of constant immigration and
emigration, the population continually oscillates.
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Alpine Instagram
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Alpine tundra is located on mountains throughout the world

at high altitude where trees cannot grow. The growing
season is approximately 180 days.
The nighttime temperature is usually below freezing. Unlike
the arctic tundra, the soil in the alpine is well drained. The
plants are very similar to those of the arctic ones and
include:
1. Tussock grasses, dwarf trees, small-leafed shrubs, and
heaths
2. Mammals: pikas, marmots, mountain goats, sheep, elk
3. Birds: grouselike birds
4. Insects: springtails, beetles, grasshoppers, butterflies
Salient Features of Tundra
• The tundra region derives its name from the Finnish word “tunturia,” which
means treeless plain.

• The tundra is characterized by a harsh, frost-laden landscape, minus-zero

temperatures, lack of precipitation, nutrients, and extremely short seasons.

• Divided into two major categories, the artic tundra and alpine tundra, the
tundra environment is characterized by a distinct climate, flora and fauna.

• The artic is renowned for its cold, desert-like conditions. Winter and summer
are its two main seasons, with spring lasting for a short duration between
winter and summer.

• Rainfall varies in different artic regions, and yearly precipitation including

melting snow, is around 6 to 10 inches.

• Summer temperatures in the artic tundra range between 37 to 54 degrees

Fahrenheit, and winter temperatures average around minus-29 degrees
Fahrenheit.
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 Instagram
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Characterized by low-nutrient soil with sparse vegetation, the artic

tundra is home to around 1,700 different species of shrubs, sedges,
mosses, lichens, grasses and 400 varieties of flowers.

Plants are adapted to sweeping winds and soil disturbances, growing

short and grouping together to resist the cold temperatures. The growing
season lasts for around 50 to 60 days. With the exception of birch trees
in the lower latitudes, no other trees inhabit the artic tundra.

Since the ground is always frozen beneath the soil’s top layer, trees
cannot send roots down. Willows grow in some tundra regions, but only
as low carpets around 3 inches high.

Tundra animal life is restricted to the challenging environment, and

reptiles and amphibians do not exist in this habitat. According to the
Physical Geography web site, the caribou, musk ox, arctic hare, voles
and lemmings are the principal herbivores, which enable a few
carnivores like the arctic fox, snow owl, polar bear, and wolf to survive.
Global Warming & Tundra Climate
• Large swaths of the Arctic tundra will be warm enough
to support lush vegetation and trees by 2050.
• Higher temperatures will lessen snow cover, which, in
turn, will decrease the sunlight reflected back into the
atmosphere and increase warming.
• About half the areas will see vegetation change, and
areas currently populated by shrubs may find woody
trees taking their place.
• One can substitute the snowy surface with the darker
surface of a coniferous tree for example, and the darker
surface of the tree will store more heat.
• It is going to exacerbate warming. Instagram
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Oil Drilling in Tundra
• The oil and gas industry wants access to areas both on land (the Arctic
Wildlife Refuge) and in the Arctic Ocean (the Chukchi and Beaufort seas),
even though oil and gas development would carve up the Arctic Refuge
with roads and industrial infrastructure, fragmenting otherwise pristine
habitat and exposing the fragile tundra and wildlife to toxic chemicals and
oil spills.

• Currently, oil and gas companies, including Shell, are attempting to begin
drilling operations in the Arctic Ocean.

• Offshore drilling threatens the sensitive coasts of both the Arctic Refuge
and the Western Arctic Reserve.

• With the oil and gas industry lacking technology to safely operate or
recover spilled oil in one of the harshest environments on Earth, these
proposals are dangerous.

• Despite what oil companies say, oil spills are part of drilling.
• In the Chukchi alone, the government has predicted a 40 percentInstagram
chance
of a significant oil spill. @tireless.study
• The Chukchi and Beaufort seas are home to
polar bears, several species of seals and whales,
millions of birds and 90 percent of the entire
Pacific walrus population.
• An oil spill could devastate critical feeding
grounds for these animals, and put them in direct
danger of exposure to oil through oil spills.
• Arctic ecosystems are less likely to recover from
spills than those in more temperate climates.
• Oil breaks down slower in cold weather, while
shorter growth and reproduction seasons means
that negative impacts persist longer.
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Forest Ecosystem

• A forest ecosystem consists of several plants, animals and

microorganisms that live in coordination with the abiotic factors of
the environment.

• Forests help in maintaining the temperature of the earth and are

the major carbon sink.

• The forest ecosystems are classified into three major types viz.,
tropical forest, temperate forest, and coniferous forest.

• These forests are distributed around the earth generally on a

gradient, from latitudes north to south, or from low altitudes to high
altitudes.

• Forests can also be evergreen and deciduous based on the season

in which the trees shed their leaves.

• On the basis of types of leaves, they can be distinguished into

broad-leafed or needle-leafed forests. Instagram
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Tropical Rain Forests Instagram
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• These are found close to the equator where the temperature and humidity remain
high throughout the year.

• They are found in areas where the annual rainfall exceeds 200 cm and is
distributed throughout the year.

• Tropical rainforests are among the richest ecosystems in terms of biodiversity.

They have very high floral and faunal diversity

• An important feature of the flora here is that it is vertically stratified. The forests
have very tall trees with a dense canopy at the top. The trees are often covered
with vines, creepers, lianas, epiphytic orchids, and bromeliads. The layer below it
consists of shrub variety trees like ferns and palm.

• The soils in tropical rainforests are known as red latosols or lateritic soils. They are
very thick. They have undergone high rates of leaching which makes them
unsuited for agriculture. However, if left undisturbed without high precipitation,
they experience fast recycling of nutrients from the decomposing litter and can
regain their lost nutrient value.

• These forests do not have a dense undergrowth due to lack of adequate sunlight
at the bottom. The dense canopy of these forests blocks most of the sunlight from
reaching the bottom layer.
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• These are broad-leaf evergreen forests found in the

regions of high rainfall with a low annual range of
temperatures.

• The biodiversity in these forests is similar to that found in

the tropical rainforests. Epiphytes are common here.

Tropical Seasonal Forests

• Also known as the monsoon forests, they are found in

regions where the annual rainfall is high but is
concentrated in a few months of the year and there are
distinct wet and dry seasons.

• These forests are found in India, South-east Asia,

northern Australia, central and South America, western
Africa, and the tropical islands of the western Pacific.
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• These are found in temperate latitudes which exhibit a marked

seasonality with respect to rainfall and temperature.

• These forests experience dense fog and high rainfall. Fog is

considered to be a more important water source than rainfall.

• Biodiversity of these forests is higher than other temperate forests but

not as high as tropical rainforests.

Temperate Evergreen Forests

• These forests are found in regions with a Mediterranean type of

climate. The summers are warm and dry, and the winters are cool and
moist.

• The region supports the growth of short, broad-leaved evergreen trees.

• Dry summers make this region prone to forest fires. However, the
plants here have adapted themselves to forest fires which enables
them to regenerate quickly even after getting burnt.
Temperate Deciduous Forests
• These are found in regions with a moderate climate.
• The trees are broad-leaved which shed their leaves
in autumn in order to save water during the dry
season by reducing transpiration losses.
• The forest appears bare in winters but new foliage
starts to appear in the spring.
• The rainfall is uniformly distributed throughout the
year.
• These forests contain podzolic soils and are
sufficiently deep.
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Coniferous Forests
• These are also known as boreal forests.
• These are found in regions with long and cold winters and
short and cool summers. They are found in the northern
latitudes close to the Arctic circle.

• The trees are of evergreen variety with prominent plant species

such as pine, spruce, fir etc.

• They harbour unique faunal species such as red fox, lynx,

arctic wolf, squirrel, amphibians such as Hyla, Rana (both are
frogs) etc.

• The soils of coniferous forests are thin podzols which are

rather poor in nutrient content. This is because the weathering
of rocks and the decomposition of ground litter proceeds
slowly in the cold climate. Microbial activity on the dead
organic matter is slow under cold conditions. Instagram
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• The soils are also acidic in nature.
• This is because of the movement of water through the soil in
large quantities without any significant counter-movement
upwards due to slow evaporation.

• Essential soluble nutrients such as calcium, nitrogen, potassium

are leached from the soil even beyond the reach of the roots.

• Since there are no alkaline cations which can neutralize the

accumulating organic acids from the litter, the soils become
acidic.

• They are also mineral deficient.

• The productivity of a coniferous forest is much less than a
tropical or a temperate forest due to insufficient solar radiation.

• These forests have a low level of community stability as against

other forest types due to lower biodiversity.
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• Climate, soil and topography are the major
factors that influence Natural Vegetation of a
place.
• The main climatic factors are rainfall and
temperature. The amount of annual rainfall has
a great bearing on the type of vegetation.

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• Temperature is the major factor in Himalayas and
other hilly regions with an elevation of more than
900 metres.
• As the temperature falls with altitude in the
Himalayan region the vegetal cover changes with
altitude from tropical to sub-tropical, temperate
and finally alpine.
• Soil is an equally determining factor in few
regions. Mangrove forests, swamp forests are
some of the examples where soil is the major
factor.
• Topography is responsible for certain minor types
e.g. alpine flora, tidal forests, etc..
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 Indian Forest Types
• India has a diverse range of forest from the rainforest
of Kerala in the south to Alpine pastures of Ladakh in
the north, from the deserts of Rajasthan in the west to
the evergreen forests in the north east.

• Climate, soil type, Topography, and elevation are the

main factors that determine the type of Forest.

• Forests varied according to their nature and

composition, the type of climate in which they thrive,
and its relationship with the surrounding environment

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Champion & Seth Classification of Natural Vegetation
of India

• Classification of Natural Vegetation of India is primarily

based on spatial and annual variations in rainfall.

• Temperature, soil and topography are also considered.

• India’s vegetation can be divided into 5 main types
and 16 sub-types as given below.

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A. Moist Tropical Forests C. Montane Sub-tropical Forests

• Tropical Wet Evergreen • Sub-tropical broad leaved hill

• Tropical Semi-Evergreen • Sub-tropical moist hill (pine)
• Tropical Moist Deciduous • Sub-tropical dry evergreen
• Littoral and Swamp
B. Dry Tropical Forests

• Tropical Dry Evergreen

• Tropical Dry Deciduous
• Tropical Thorn

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D. Montane Temperate Forests E. Alpine Forests

• Montane Wet Temperate • Sub-Alpine

• Himalayan Moist Temperate • Moist Alpine scrub
• Himalayan Dry Temperate • Dry Alpine scrub

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 Moist Tropical Forests
Tropical Wet Evergreen Forests or Rain Forests
Climatic Conditions
• Annual rainfall exceeds 250 cm
• The annual temperature is about 25°-27°C
• The average annual humidity exceeds 77 per
cent and
• The dry season is distinctly short.

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Characteristics
• Evergreen: Due to high heat and high humidity, the trees of
these forests do not shed their leaves together.

• Mesosphytic: Plants adopted to neither too dry nor too wet type
climate.

• Lofty: The trees often reach 45 – 60 metres in height.

• Thick Canopy: From the air, the tropical rain forest appears like
a thick canopy of foliage, broken only where it is crossed by
large rivers or cleared for cultivation.

• All plants struggle upwards (most ephiphytes) for sunlight

resulting in a peculiar layer arrangement. The entire morphology
looks like a green carpet when viewed from above.

• Less undergrowth: The sun light cannot reach the ground due
to thick canopy. The undergrowth is formed mainly of bamboos,
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epiphytes

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Distribution

• Western side of the Western Ghats (500 to 1370 metres above

sea level).

• Some regions in the Purvanchal hills.

• In the Andaman and Nicobar Islands.
Timber

• Hardwood: The timber of these forests is fine-grained, hard and

durable.

• It has high commercial value but it is highly challenging to exploit

due to dense undergrowth, absence of pure stands and lack
of transport facilities [Read previous posts on Climatic regions
to understand how lumbering industry works in Equatorial
Rainforests (hardwood) and Taiga Climatic (softwood) conditions].

• The important species of these forests are mahogany, mesua,

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Tropical Semi-Evergreen Forests

• They are transitional forests between tropical wet

evergreen forests and tropical deciduous forests.

• They are comparatively drier areas compared to

tropical wet evergreen forests.
Climatic Conditions

• Annual rainfall is 200-250 cm

• Mean annual temperature varies from 24°C to 27°C
• The relative humidity is about 75 per cent
• The dry season is not short like in tropical evergreen
forests. Instagram
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Distribution
• Western coast
• Assam
• Lower slopes of the Eastern Himalayas
• Odisha and
• Andamans.

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Characteristics

• The semi-evergreen forests are less dense.

• They are more gregarious [living in flocks or colonies – more
pure stands] than the wet evergreen forests.

• These forests are characterized by many species.

• Trees usually have buttressed trunks with abundant
epiphytes.

• The important species are laurel, rosewood, mesua, thorny

bamboo – Western Ghats, white cedar, Indian chestnut,
champa, mango, etc. – Himalayan region.
Timber
• Hardwood: Similar to that in tropical evergreen forests except that
these forests are less dense with more pure stands (timber
industry here is better than in evergreen forests). Instagram
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 Instagram
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Tropical Moist Deciduous Forests
Climatic Conditions
• Annual rainfall 100 to 200 cm.
• Mean annual temperature of about 27°C
• The average annual relative humidity of 60
to 75 per cent.
• Spring (between winter and summer) and
summer are dry.

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Characteristics
• The trees drop their leaves during the spring and
early summer when sufficient moisture is not
available.
• The general appearance is bare in extreme summers
(April-May).
• Tropical moist deciduous forests present irregular
top storey [25 to 60 m].
• Heavily buttressed trees and fairly complete
undergrowth.
• These forests occupy a much larger area than the
evergreen forests but large tracts under these
forests have been cleared for cultivation. Instagram
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Distribution

• Belt running along the Western Ghats surrounding the belt

of evergreen forests.

• A strip along the Shiwalik range including terai and bhabar

from 77° E to 88° E.

• Manipur and Mizoram.

• Hills of eastern Madhya Pradesh and Chhattisgarh.
• Chota Nagpur Plateau.
• Most of Odisha.
• Parts of West Bengal and
• Andaman and Nicobar islands.
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Timber
• These provide valuable timer like Teak.
• The main species found in these forests are teak,
sal, laurel, rosewood, amla, jamun, bamboo, etc.
• It is comparatively easy to exploit these forests
due to their high degree of gregariousness (more
pure stands).

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Littoral and Swamp Forests

• They can survive and grow both in fresh as well as

brackish water (The mixture of seawater and fresh
water in estuaries is called brackish water and its
salinity can range from 0.5 to 35 ppt).

• Occur in and around the deltas, estuaries and creeks

prone to tidal influences (delta or tidal forests).

• Littoral (relating to or on the shore of the sea or a lake)

forests occur at several places along the coast.

• Swamp forests are confined to the deltas of the Ganga,

the Mahanadi, the Godavari, the Krishna and the
Cauvery.
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• Dense mangroves occur all along the coastline in
sheltered estuaries, tidal creeks, backwaters, salt
marshes and mudflats. It provides useful fuel wood.
• The most pronounced and the densest is the
Sunderban in the Ganga delta where the
predominant species is Sundri (Heriteera).
Timber
• It provides hard and durable timber which is used for
construction, building purposes and making boats.
• The important species found in these forests are
Sundri, agar, rhizophora, screw pines, canes and
palms, etc.
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 Dry Tropical Forests
Tropical Dry Evergreen Forests
Distribution

• Along the coasts of Tamil Nadu.

Climatic Conditions

• Annual rainfall of 100 cm [mostly from the north-east monsoon winds

in October – December].

• Mean annual temperature is about 28°C.

• The mean humidity is about 75 per cent.
• The growth of evergreen forests in areas of such low rainfall is a bit
strange.

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Characteristics
• Short statured trees, up to 12 m high,
with complete canopy.
• Bamboos and grasses not conspicuous.
• The important species are jamun,
tamarind, neem, etc.
• Most of the land under these forests has
been cleared for agriculture or casuarina
plantations.

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Casuarina plantation
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 Casuarina plantation
• It resembles feathery conifer in general appearance.
• They are rapid-growing, carefree species for sites and
climates as varied as coastal sand dunes, high
mountain slopes, hot humid tropics, and semi-arid
regions.

• They have the ability to fix atmospheric nitrogen. It

grows 15 to 25 metres in height on an average.

Distribution
Casuarina is the most popular farm forestry in the states
of Andhra Pradesh, Tamil Nadu, West Bengal, Odisha,
Maharashtra, Gujarat, and Karnataka.
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 Benefits

• Reduces damage in the event of natural calamities.

• Line planting in the coastal areas helps in controlling
the wind force.
• It is also used for tourism promotion in view of its
ornamental appearance.
• It provides top quality firewood.
• The wood is suitable for paper pulp and useful raw
material for the manufacture of paper for writing,
printing, and wrapping.
• It is got some serious medicinal values as well.
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Wasteland development

• The characteristics which make it a suitable

species for wasteland development include
adaptability to wide range of habitats, fast
growth, salt tolerant, drought resistant, ability to
reclaim land and stabilize sand dunes.
• Intercrops such as groundnut, cucumber,
watermelons, sesamum, and pulses can also be
raised along with the plantation.

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Tropical Dry Deciduous Forests
Climatic Conditions

• Annual rainfall is 100-150 cm.

Characteristics

• These are similar to moist deciduous forests and shed their leaves in dry season.
• The major difference is that they can grow in areas of comparatively less rainfall.
• They represent a transitional type – moist deciduous on the wetter side and thorn
forests on the drier side.

• They have closed but uneven canopy.

• The forests are composed of a mixture of a few species of deciduous trees rising
up to a height of 20 metres.

• Undergrowth: Enough light reaches the ground to permit the growth of grass and
climbers.
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Distribution
• They occur in an irregular wide strip running from the
foot of the Himalayas to Kanniyakumari except in
Rajasthan, Western Ghats and West Bengal.
• The important species are teak, axlewood, rosewood,
common bamboo, red sanders, laurel, satinwood,
etc.
• Large tracts of this forest have been cleared for
agricultural purposes.
• These forests have suffer from over grazing, fire, etc.

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Tropical Thorn Forests
Climatic Conditions

• Annual rainfall less than 75 cm.

• Humidity is less than 50 per cent.
• Mean temperature is 25°-30°C.
Characteristics

• The trees are low (6 to 10 metres maximum) and widely scattered.

• Acacias and Euphorbias are very prominent.
• The Indian wild date is common. Some grasses also grow in the rainy
season.

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Distribution
• Rajasthan, south-western Punjab, western
Haryana, Kachchh and neighbouring parts of
Saurashtra.
• Here they degenerate into desert type in the Th
desert.
• Such forests also grow on the leeside of the
Western Ghats covering large areas of
Maharashtra, Karnataka, Telangana, Andhra
Pradesh and Tamil Nadu.
• The important species are neem, babul, cactii,
etc. Instagram
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 Montane Sub-Tropical Forests
Sub-tropical Broad-leaved Hill Forests
Climatic conditions
• Mean annual rainfall is 75 cm to 125 cm.
• Average annual temperature is 18°-21°C.
• Humidity is 80 per cent.
Distribution
• Eastern Himalayas to the east of 88°E longitude
at altitudes varying from 1000 to 2000 m.

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Characteristics
• Forests of evergreen species.
• Commonly found species are evergreen oaks, chestnuts, ash,
beech, sals and pines.

• Climbers and epiphytes [a plant that grows non-parasitically on a

tree or other plant] are common.

• These forests are not so distinct in the southern parts of the

country. They occur only in the Nilgiri and Palni hills at 1070-1525
metres above sea level.

• It is a “stunted rain-forest” and is not so luxuriant as the true

tropical evergreen.

• The higher parts of the Western Ghats such as Mahabaleshwar, the

summits of the Satpura and the Maikal Range, highlands of Bastar
and Mt. Abu in the Aravali Range carry sub-types of these forests.
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Sub-tropical Moist Pine Forests Instagram
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Distribution

• Western Himalayas between 73°E and 88°E longitudes

at elevations between 1000 to 2000 metres above sea
level.

• Some hilly regions of Arunachal Pradesh, Manipur,

Naga Hills and Khasi Hills.

Timber

• Chir or Chil is the most dominant tree which forms

pure stands.

• It provides valuable timber for furniture, boxes and

buildings.

• It is also used for producing resin and turpentine.

Sub-tropical Dry Evergreen Forests
Distribution

• Found in the Bhabar, the Shiwaliks and the western Himalayas

up to about 1000 metres above sea level.

Climatic Conditions

• Annual rainfall is 50-100 cm (15 to 25 cm in December-March).

• The summers are sufficiently hot and winters are very cold.
Characteristics

• Low scrub forest with small evergreen stunted trees and shrubs.
• Olive, acacia modesta and pistacia are the most predominant
species.
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 Montane Temperate Forests
Montane Wet Temperate Forests
Climatic Conditions

• Grows at a height of 1800 to 3000 m above sea level

• Mean annual rainfall is 150 cm to 300 cm
• Mean annual temperature is about 11°C to 14°C and
the

• Average relative humidity is over 80 per cent.

Distribution

• Higher hills of Tamil Nadu and Kerala, in the Eastern

Himalayan region. Instagram
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Characteristics
• These are closed evergreen forests. Trunks
have large girth.
• Branches are clothed with mosses, ferns and
other epiphytes.
• The trees rarely achieve a height of more than
6 metres.
• Deodar, Chilauni, Indian chestnut, birch,
plum, machilus, cinnamomum, litsea,
magnolia, blue pine, oak, hemlock, etc. are
important species.
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Himalayan Moist Temperate Forests
Climatic Conditions
• Annual rainfall varies from 150 cm to 250 cm
Distribution
• Occurs in the temperate zone of the
Himalayas between 1500 and 3300 metres.
• Cover the entire length of this mountain
range in Kashmir, Himachal Pradesh,
Uttarakhand, Darjeeling and Sikkim.
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Characteristics

• Mainly composed of coniferous species.

• Species occur in mostly pure strands.
• Trees are 30 to 50 m high.
• Pines, cedars, silver firs, spruce, etc. are most important
trees.

• They form high but fairly open forest with shrubby

undergrowth including oaks, rhododendrons and some
bamboos.

Timber

• It provides fine wood which is of much use for construction,

timber and railway sleepers.
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Himalayan Dry Temperate Forests

Climatic Conditions

• Precipitation is below 100 cm and is mostly in the form of

snow.

Characteristics

• Coniferous forests with xerophytic shrubs in which

deodar, oak, ash, olive, etc are the main trees.

Distribution

• Such forests are found in the inner dry ranges of the

Himalayas where south-west monsoon is very feeble.

• Such areas are in Ladakh, Lahul, Chamba, Kinnaur,

Garhwal and Sikkim. Instagram
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 Alpine Forests
• Altitudes ranging between 2,900 to 3,500.

• These forests can be divided into:

• (1) sub-alpine;

• (2) moist alpine scrub and

• (3) dry alpine scrub.

Sub Alpine Forests

These extend from Kashmir to Arunachal Pradesh between 2900 to 3500
meters.

In the Western Himalayas, the vegetation consists mainly of Juniper,

Rhododendron, Willow, and Black Currant.

In the eastern and high humidity the timberline in this part is higher than that in
the West.
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• These are found all along the Himalayas and on the

higher hills near the Myanmar border.
• It has a low scrub, dense evergreen forest,
consisting mainly of rhododendron and birch.
• Mosses and ferns cover the ground in patches. This
region receives heavy snowfall.
Dry alpines
• These are found from about 3000 meters to about
4900 meters.
• Dwarf plants predominate, mainly the black juniper,
the drooping juniper, honeysuckle, and willow.
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 Deforestation
Indiscriminate felling of trees at a result of
urbanisation, industrialisation, mining operations,
the use of wood for domestic and other purposes,
have caused heavy depletion of Forests.

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Causes
Shifting Cultivation
• In this Practice a Patch of Land is Cleared
vegetation is Burned and the Ash is Mixed with the
Soil and Adding Nutrients to the Soil.
• The Patch of Land is Cleared for Using the Crops
and two or three years is Modest.
• All that is Required is the Method of the Cultivation
is a Set of the Simple tools and not required a High
Level Mechanism.

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Development Project

The Human Population is Increased So with Requirements. Many

of the Project Immerse Deforestation.

Fuel Requirements

The Increasing Demands of the Firewood with the Growing

Population increases with the Greater Pressure on the Forests.

Raw Materials

Wood is used for the Various Industries for Making the Paper,
Plywood and the Match Sticks.

Other Causes

Deforestation also Causes the Overgrazing and Agriculture, mining

and Urbanization, Pest Disease, Communication Activities.
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 Grassland Ecosystem
Grassland ecosystem is found to occur in regions where the annual
rainfall ranges between 25-75 cm which is more than the precipitation in
a desert but not enough to support the growth of a forest.

Grasslands are typically a vegetative formation which is found in

temperate climates. In India, the grasslands are a mix of tropical
savanna and temperate steppe variety.

In the high altitudes of the Himalayas, temperate grasslands are found.

In India, steppe formations are found to occur in western Rajasthan

where the climate is semi-arid with a dry season of 10-11 months, and
the average annual rainfall is less than 20 cm. They occupy large areas
of sandy and saline soil.

The soil here is always exposed, sometimes rocky but often sandy with
fixed or mobile sand-dunes. Forage is found only during the brief wet
season. The layer of grass is sparse and mainly consists of annual grass
species. Instagram
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In eastern and central parts of Rajasthan, dry savanna
type of grasslands has developed.
The region experiences an annual rainfall of around
500mm with a dry season of 6 to 8 months.
The rainfall supports the growth of a sparse
population of trees like Khetri (Prosopis Cineraria)
whose light shade favours the growth of the grasses.
A major difference between savannas and steppes is
that savanna forage is largely from grasses that not
only grow during the wet season but also from the
small amount of regrowth in the dry season whereas
in the steppes all the forage is provided only during
the brief wet season.
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Types of Grasslands
Four major types of grasslands found to occur in different regions
of the Indian subcontinent based on climatic conditions.

Semi-Arid Zone
• The grassland here is of the Sehima-dichanthium type.
• It is found in the northern portion of Gujarat, Rajasthan
(excluding Aravalis), western Uttar Pradesh, Delhi, and
Punjab.

• The region's topography consists of hills spurs and sand

dunes.

• The vegetative species found here include Calotropis

gigantic, Cassia auriculata, Prosopis cineraria, Salvadora
oloides and zizyphus Nummularia which make the grassland
look like a scrub. Instagram
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Dry sub-Humid Zone

• This climatic zone covers the whole of peninsular India,

except the Nilgiris.

• The grassland found here is of the Dichanthium cenchrus-

lasitrrus type which covers the maximum area among all
the grassland types found in India.

• The vegetative species here include thorny bushes such

as Acacia catechu, Mimosa Zizyphus (ber) and sometimes
fleshy Euphorbia, along with short tree varieties such as
Anogeissus latifola, Soymida febrifuga and other
deciduous species

• Dichanthium grass is found on level soils and covers up to

80 percent of the ground. Sehima grass is found on the
gravel and coverage is around 27 percent.
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Moist sub-Humid Zone

• This climatic zone covers the alluvial plains of Ganga in northern

India.

• The grassland found here is of the Phragmities-sacchrum-

imperata type.

• The topography of the region is flat, low lying, and poorly

drained soils.

• The grasses found here include Bothriochloa pertusa, Cynodon

dactylon, and Dichanthium annulatum which grow in the
transition zones.

• The common vegetative species found here include Acacia

arabica, Anogeissus latifolia, Butea monosperma, Phoenix
sylvestris and Zizyphus nummularia. However, some of these
species are replaced by Borassus species in the palm savannas
particularly in the ones near Sunderbans. Instagram
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Humid Montane Zone
• The grassland found here is of the Themeda -
Arundinella type.
• This climatic zone covers the humid montane and
moist sub-humid areas of Jammu and Kashmir,
Himachal Pradesh, Punjab, Uttar Pradesh, West
Bengal, Assam, and Manipur.
• The grasslands here are formed as a result of
shifting cultivation and sheep grazing.

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The economic importance of grasslands Instagram
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• India supports a huge livestock population of all varieties. According to

19th Livestock Census, 2012 India's total livestock population is over 512
million.

• Livestock plays a crucial rule in the rural economy. It's a major source of
food, nutrition, draught power, fuel, and raw material for cottage industries
in the village. They also supplement the income of farmers dependent on
crop cultivation.

• The livestock needs fodder for survival and growth but there is a dearth of
it in India. Only around 13 million hectares are classified as permanent
grazing lands. Large portions of these lands are categorized as degraded
lands.

• Hence it is essential to preserve and revive the grassland ecosystems, not

only to sustain the livestock population but also to support the biodiversity
associated with the region.

• In order to promote research in the development of grassland ecosystems

the government has created two institutions viz., Indian Grasslands and
Fodder Research Institute, Jhansi; and Central Arid Zone Research
Institute, Jodhpur.
Impact of Grazing on Grasslands Instagram
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• Excessive grazing by livestock has resulted in the deterioration of

grassland ecosystems. The mulch cover on the soil reduces which
makes the microclimate of the region dry facilitating the invasion by
xerophytic plants.

• Due to the removal of humus cover, the soil surface gets trampled
upon heavily. This reduces the infiltration capacity of the soil and
accelerates soil runoff during the rains. This also makes the region
vulnerable to drought.

• These changes disrupt the energy flow in the ecosystem and affect
the stratification and periodicity of primary producers. This can lead
to a breakdown of the biogeochemical cycles of nitrogen, water,
and carbon.

• Intensive grazing of grasslands opens up the bare soil which

facilitates the growth of populations of burrowing animals such
mice, jack-rabbits, prairie dogs, gophers etc. The new habitat for
these animals can render large areas of forage lands sterile.
Role of Fire
• Fire is known to play an important role in the
management of grassland ecosystem.
• In moist conditions, fire favours grass over trees
whereas in dry conditions fire often protects the
grasslands against the invasion of alien species
such as desert shrubs.
• The forage yields also increase after a cycle of
burning and regrowth. E.g., Cynodon dactylon.

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 Desert Ecosystem Instagram
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A desert is a geographical region in which the annual rainfall is less than

25 cm. Sometimes, in hot regions even if the rainfall exceeds 25 cm in a
year, deserts can form if the rainfall is concentrated only for a few days.

In the sub-tropics, a desert is formed due to the presence of high-

pressure belt which restricts cloud formation and rainfall.

In the temperate latitudes, a desert is formed in the rain shadow region

such as an inter-montane plateau where high mountains block moisture-
laden winds blow from the sea.

The type of desert, particularly its climate, is defined by latitude and

altitude.

In the tropics, close to the mean sea level hot deserts are formed (e.g.,
Thar desert), whereas at high altitudes cold deserts can be found (e.g.,
Ladakh).

As the distance from the equator increases, cold deserts are found to
occur particularly in the continental interiors (e.g., Gobi desert in China).
The common plant species which are found in deserts include the
creosote bush, cactus, Ferocactus etc. In shallow depression with
salt deposits Sarcobatus, geesewood, seepwood and salt grasses
are the common vegetative species.

Water is the dominant limiting factor which determines the

productivity of a desert ecosystem.

If the soils are suitable, irrigation can convert the region into a
productive agricultural land (e.g., parts of Rajasthan irrigated by the
Indira Gandhi canal).

The productivity of a desert ecosystem is mainly dependent on

how the biogeochemical cycles and energy flow of the region are
managed by man because of artificial irrigation.

As the rate of irrigation increases, salts are left behind on desert

soils, due to capillary action combined with excessive evaporation,
which can limit their productivity in the long run. Instagram
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Adaptation by plants in a desert
• Leaves are modified into thorns to reduce water
loss. The leaves and the stem are succulent and
water-storing.
• In some plants, the stem contains chlorophyll to
facilitate photosynthesis in the absence of leaves.
• They have an extensively developed root system
to absorb water from greater distances and
depths.
• The seeds only germinate during the short rainy
season. Similarly, the plants reproduce and bloom
only when the water is available.
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Hot Desert in India
• It is known by the name, Thar desert.
• The climate of the region is characterized by continuous drought with
rainfall being irregular and scanty. The monsoon winds do not bring
any significant rainfall to this region since the adjoining Aravallis lie
parallel to the rain-bearing winds. The winter rains of north India,
brought by Western disturbances, do not penetrate into this region.

• The cold weather (winter) season begins from the middle of

November and continues up to the middle of March. This season is
characterized by extreme variations in temperatures. The
temperatures often drop below the freezing point at nights.

• The rest of the year experiences hot weather. During April to June, the
heat becomes intense with scorching winds prevailing over the
region. These winds have a desiccating effect, removing all the
moisture from the surrounding atmosphere. The relative humidity in
the region is always low. Such hostile climate necessitates that the
flora and fauna which survive in the region possess certain special
adaptations. Instagram
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• The adaptations of desert species are mainly for two reasons - to enable them to
obtain water, and to retain the water thus obtained.

• Most of the desert vegetation consists of scrub variety species including

perennial herbs and shrubs which are capable of resisting and surviving drought
for a long period. There a few species of trees which can be found. These are
usually stunted and thorny, adaptations which are necessary to survive the dry
weather and to protect themselves from herbivores.

• The desert vegetation is mainly of two types viz., the one which is directly
dependent on rains, and the other which is dependent on subterranean water.

• The plant species which are directly dependent on rain are subdivided into two
types - ephemerals and rain perennials. The ephemerals are delicate species
without any special (xerophilous) adaptations. They have slender stems, root-
systems and also large flowers. They appear soon after the rains, grow and
bloom with flowers and fruits for a very short period. They die out as soon as the
soil moisture dries up. The rain perennials have an elaborate underground root
system. Only during the rainy season, they become visible above the ground.

• The second variety of plant species is dependent on subsurface water. Most of

these plants are capable of absorbing water from deep below the ground with the
help of a well-developed root system. The main part of the root system is usually
a slender, woody tap root of great length. Instagram
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• Various other xerophilous adaptations by the plants in this
region include reduced leaves, succulence, coatings of wax,
thick hairy growth, protected stomata, thick cuticle etc. All of
these become necessary to reduce water loss due to
transpiration.

• Some endemic floral species of the Thar desert include

Calligonum Polygonoides, Tecomella undulate, Prosopis
cineraria, Sueda fruticosa, and Cenchrus biflorus etc.

• The important mammal species of the desert include

chinkara, blackbuck, desert fox, wild ass, caracal,
sandgrouse etc. These are found in the grasslands, open
plains and also near saline depressions. the desert
ecosystem and its grasslands are home to the Great Indian
Bustard, India's largest flying bird. The Great Rann of Gujarat
is known for the nesting grounds of flamingoes and the only
known population of Asiatic wild ass. The Great Rann is
along the way of migration of many cranes and flamingoes.
Cold Desert or Temperate Desert
The cold desert in India covers the areas of Ladakh, Leh,
and Kargil in Jammu and Kashmir; Spiti Valley of Himachal
Pradesh; parts of Uttarakhand and Sikkim. These areas
remain arid because they do not come under the influence
of monsoon winds over India. They lie in the rain shadow
areas of the Himalayas.
The weather in this region is severe with extremely cold
conditions during winters. The terrain is denuded of soil
which can support the growth of plants, due to prolonged
dry spells and fast blowing winds. Scattered and isolated
shrubs can be found here but they are overgrazed. The
grazing period is short, less than 4 months in duration.
Important floral species such as oak, pine, birch, deodar,
and rhododendron are found at the edges of the desert.
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Yaks, goats, and dwarf cows are the prominent animals
found in this region. Other important species include the
highly adaptative, rare and endangered fauna such as
Asiatic Ibex, Tibetan Argali, Tibetan Antelope (chiru),
Tibetan Gazelle, Snow Leopard, Brown Bear, Tibetan
Wild Ass (Kiang), Ladakh Uriyal, Bharal, Tibetan Wolf,
Wild Dog etc.
Prolonged dry spells characterize the region with mean
annual precipitation being less than 40 cm. Much of it
occurs as snowfall during the months of November
through March. The temperatures remain close to the
freezing point throughout the year and drop as low as
-50 degrees Celsius in winters. The soils are sandy to
loamy with neutral to alkaline in character. They are poor
in organic content, have a low water retention capacity
and prone to severe wind erosion. Instagram
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 Desertification
Desertification is a process in which there is a gradual
destruction of the biological potential of land which
ultimately results in desert-like conditions.
In semi-arid and arid areas, the ecosystem is fragile. The
process of restoration of the disturbed ecosystem in
these areas is very slow.
Human interventions like deforestation, mining etc.
further hasten the process of desertification in these
areas.
In India, the problem of desertification is severe in the
states of Rajasthan, Gujarat, Haryana, and Punjab which
contain areas adjoining the desert (Thar).
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The most important cause of desertification is human
intervention.
Natural factors such as changes in climate, drought etc
get worsened by growing population pressures and lack of
alternative employment opportunities in these areas.
This forces the people in areas surrounding the Thar to fall
back on animal rearing which often leads to excessive
grazing of pastures.
Thus the main reasons for desertification can be identified
as population pressure, the spread of agriculture,
deforestation, increase in cattle population, other
developmental activities.
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Status of Desertification in India
According to the Desertification and Land
Degradation Atlas of India, 2016 (released by
ISRO), 96 million hectares or close to 29 percent
of India's area is undergoing degradation.
However, the good news is that the extent of
desertification is slowed down due to efforts
such as land reclamation.
According to the Desertification Atlas of 2007,
the extent of degraded lands in India is over 105
million hectares or about 32 percent of India's
areas. Instagram
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Control Measures taken by India
India became a signatory to the United Nations Convention to Combat Desertification (UNCCD)
and has submitted several National Reports to UNCCD, including the data of Desertification
Atlas, detailing the steps taken to combat desertification. In 2001, a National Action Programme
to combat desertification was prepared. Other major programmes to address the issues of
desertification and land degradation include:

• Desert Development Programme.

• Integrated Watershed Management Programme which is now subsumed under Pradhan

Mantri Krishi Sinchai Yojana.

• National Mission on Green India which is a part of National Action Plan on Climate Change.

• National Afforestation Programme.

• Soil Conservation in the Catchment of River Valley Projects and Flood Prone Rivers.

• National Watershed Development Project for Rainfed Areas.

• Fooder and Feed Development Scheme - a component of Grassland Development

including Grass Reserves

• Command Area Development and Management Programme. Instagram

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Afforestation
The desert and its adjoining areas in the states of Rajasthan, Gujarat,
Haryana, Punjab, and the Trans-Himalayan region contain scarce
vegetation which accelerates the problem of desertification.

Population pressures such as consumption of wood for fuel (firewood),

timber, fodder, grazing of pastures etc., increase the susceptibility of the
region to soil erosion by wind and water.

Presence of vegetative cover reduces the effect of forces of soil erosion

and also modifies the micro-climate in a hostile region. Thus,
afforestation is a major tool to combat desertification and also to meet
the livelihood needs of the population living in and around the desert
areas.

However, afforestation measures have to address the challenges of a

hostile climate, a poor nutrient content of the soil and its lack of
moisture retaining capacity, excessive grazing by cattle, erosion due to
wind and water etc.
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 India State of Forest Report (ISFR) 2019
Context : The Ministry for Environment, Forests and
Climate Change has released the India State of Forest
Report (ISFR), 2019.
ISFR is a biennial publication of Forest Survey of India (FSI),
an organization under the Ministry of Environment Forest &
Climate Change.
The ISFR assesses the forest and tree cover, bamboo
resources, carbon stock and forest fires.
The 2019 report for the first time has assessed the
qualitative nature of the forest cover, including listing its
biodiversity and the type of plants and trees found.
It also created a national forest inventory for the first time
on produce from forests. Instagram
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Key Findings

Forest Cover

Forest Cover (Area-wise) : Madhya Pradesh> Arunachal Pradesh> Chhattisgarh>

Odisha> Maharashtra.

Forest Cover (Percentage): Mizoram (85.4%)> Arunachal Pradesh (79.63%)>

Meghalaya (76.33%)

Increase in Forest Cover

The country’s forest cover includes all patches of land with a tree canopy density
of more than 10% and more than 1 hectare in area, irrespective of land use,
ownership and species of trees.

The total forest cover of the country is 7,12,249 sq km which is 21.67% of the
geographical area of the country.

The top five states to have shown an increase in forest cover include Karnataka
(1,025 sq km) > Andhra Pradesh (990 sq km) > Kerala (823 sq km) > J&K (371 sq
km) > Himachal Pradesh (334 sq km).
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Decline of Forest Cover in North Eastern Region

Total forest cover in the North Eastern region is 1,70,541 sq km, which
is 65.05% of its geographical area.

There has been a decrease of forest cover to the extent of 765 sq km

(0.45%) in the region. Except Assam and Tripura, all the States in the
region show decrease in forest cover.

Forest Cover in Tribal Districts

The total forest cover in the tribal districts is 4,22,351 sq km, which is
37.54% of the geographical area of these districts.

There has been a decrease of 741 sq km of forest cover within the

Recorded Forest Area/ Green Wash (RFA/GW) in the tribal districts and
an increase of 1,922 sq km outside.

There has been a decline in tree cover inside forests due to tribal
populations getting “land titles” (patta) and there has been a rise in
trees outside the forest area due to an increase in tree plantation and
afforestation activities. Instagram
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Increase in the tree cover Instagram
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Tree cover comprises of tree patches of size less than 1 hectare occurring outside
the recorded forest area.

The tree cover of the country is estimated as 95,027 sq km which is 2.89% of the
geographical area.

Maharashtra has had the highest increase in tree cover and a large part of that is
due to horticulture.

In comparison to 2017
The 2019 survey has found an increase of 5,188 sq km in total forest and tree
cover in the country.

Tree and forest cover together made up 24.56% (8,07,276 sq km) of India's area.
In the last assessment it was 24.39%.

The nation’s tree and forest cover has largely hovered from 21-25% and is short of
the National Forest Policy, 1988, which envisages 33% to be under such cover.

Mangrove cover in the country has increased by 54 sq km (1.10%) as compared to

the previous assessment.
Carbon Stock Instagram
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The total carbon stock of the country was estimated at 7124 million tons,
which is an increase of 42.6 million tons from the last assessment.

It implies that India is on the right track to achieve its Paris Agreement
commitment of 2.5 -3 billion carbon sinks.

Wetlands
The total number of wetlands located within the RFA/GW is 8.13%.

Amongst the States, Gujarat has the largest area of wetlands within RFA in the
country followed by West Bengal.

Forest Produce

Dependence of fuelwood on forests is the highest in the State of Maharashtra,

whereas, for fodder, small timber and bamboo, dependence is highest in
Madhya Pradesh.

The analysis reveals that 21.40% of the forest cover of the country is highly to
extremely fire prone.
 National Forest Policy, 1988
▪ The policy aims at maintaining of environmental
stability.
▪ It looks at conserving the natural heritage of the
country by preserving the remaining natural
forests.
▪ Increasing forest/tree cover in the country through
massive afforestation and social forestry
programmes.
▪ Creating a massive people’s movement for
achieving these objectives and to minimise
pressure on existing forests.
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