BIOMES (06:23 PM)

• Any Biome is a collection of close and natural ecosystems. Each biome has one climax community.
• Biomes are divisions of the earth's land surfaces and this division is based on vegetation types.
Example- Equatorial forest, Savannah Biome
• Biomes classification
• a) Forest Biomes
• b) Grassland biomes
• c) Desert Biomes - Hot desert, Cold desert, Tundra region, etc
• Biomes of the Earth's surface- Terrestrial Biomes
• Equatorial Forest biomes (0-10 degrees in each hemisphere)
• Three-layered vegetation- Lowermost strata of vegetation, this is made of shrubs. Medium-height
trees constitute the middle layer of vegetation. Tall trees whose height is rising of medium height
trees.
• Canopy- Branches and leaves covering the ground.

• The upper 1/3rd is called as Emergent layer- Leaves are broad, hardwood. Emergent trees have
maximum life forms.
• Maximum Animal life in the equatorial forest biome is part of the tall trees on the top with a lot of
birds and bats.
• The next most abundant region for animal life is the ground-level vegetation with a lot of ground-
level birds and mammals and Million of insects living in the soil and on the ground.
• Index plants- They indicate the type of plant.
• Index plants of the equatorial biome- Rosewood, Natural Rubber, Mahogany, Ebony.
• Distinct characters- Liana Forest and Epiphytes.
• Region- Amazon River basin.
• Note- This biome has the maximum species diversity both in animal and plant life. Examples-
Amazon River Basin, Congo River Basin, South East Asia Equatorial region, West Central Africa-
Lenin, Ghana, Togo, etc.
• Tropical rainforest biome (20-30 degrees N/S)
• This biome has all the characteristics of the equatorial biome.
• Difference from Equatorial biome- Epiphytes are less, Lianas are less, Lesser species diversity,
Higher latitude.
• Index plants- Mahogany, Ebony, Natural Rubber, etc
• Region- Eastern edge of Brazil, Eastern Edge of Madagascar, All islands of West Indies, Windward
region of Western Ghat, Andaman & Nicobar, West coast of Myanmar (Arakan coast), South East
Asia outside the Equatorial Belt (Thailand, Cambodia, Vietnam), Eastern Edge of Australia.
• Temperate Evergreen Forest biome
• Climate- China type of climate (Warm to hot summers and cool winters) (25-40 degree latitude),
Rainfall is heavy in summer

New Section 3 Page 1

 Rainfall is heavy in summer
• It is like a rainforest in the middle Latitudes
• Biome characteristics- Lower lever vegetation is too layered i.e. Ground-level vegetation is well
developed, Tall trees may be softwood and hardwood
• Hardwoods are Hickory, chestnut, etc whereas Softwoods are represented by Oak, Pine, Spruce,
Fir, etc.
• Ephiphytes and Lianas are there but they are in the form of Mosses and Lichens growing from tree
trunks.
•
Mosses Lichens
Low-level plants that can do photosynthesis The symbiotic relationship between
Algae and Fungi
Soft, non-woody stem, Leaves are present Algae provide food and Fungi
provide protection
They are not vascular i.e. no xylem and phloem Fungi can not carry photosynthesis
Height is dwarf. [3-4 inches from ground] They are also non-vascular
They are Cryptograms i.e. they can not reproduce with Height is also small
seeds. They reproduce with spores.
They belong to Bryophytes They can grow on bare rocks
• Region- Southeastern China, Southeastern Australia i.e. Sydney, Southeastern Brazil (Rio de
Janeiro, Sao Paulo), Southeastern USA i.e. Florida, etc

TEMPERATE DECIDUOUS FOREST BIOME (07:27 PM)

• When the trees drop their all the leaves in dry season= Deciduous
• Climate- The Laurentian type climate/ Manchurian type of climate (35-55 degrees N/S), It also
includes the British type of climate.
• Characteristics- Very cold winter, Summers are warm, Rain is in the summer season
• Index plants- Softwoods- Spruce, Birch, Oak, Fir, and climax Hardwoods- Maple, Beech, Juglang
(Walnut)
• Biome Characteristics- The lower layer is very weakly developed.

• Region- Northeastern China, Northeastern USA, Laurentia region of Canada, New Zealand,
Western Europe, Rain-shadow regions of the Western part of North America (Leeward side of the
mountains), etc
TROPICAL DECIDUOUS FOREST BIOME (07:37 PM)

New Section 3 Page 2

TROPICAL DECIDUOUS FOREST BIOME (07:37 PM)
• It is also called a Monsoon forest biome.
• Climate- Monsoon climate i.e. Hot summer, Heavy Rain in summer, cool to warm winter.
• Characteristics- Open growth of trees i.e. Trees and then open ground, Trees are having very thick
trunks, the Width of the trunk is massive, the Barks are very thick, and these are Hardwoods.
• Leaves are broad but they are habituated in deciduous settings i.e. they lose the leaves in the dry
season. These are characterized by Huge areas covered with Bamboo.
• Species diversity- Lot of species diversity.
• Index plants- Sal and Teak.
• Biome characteristics- The lower layer of vegetation is very well developed.

• Region- Asia region, Peninsular South East Asia, South Asia- India, Pakistan, Bangladesh, North
Australia, Southern China.
MEDITERRANEAN FOREST BIOME (07:44 PM)
• It is part of the Mediterranean climate.
• Characteristics- No rain in summer, Westerlies come onshore on the edges of the landmass,
Summers are dry (Influence of Sub-tropical high-pressure belt).
• Biome characteristics- Vegetation is evergreen despite the dry season.
• [* Why the vegetation is evergreen?- Forest biome is developed at the edges of the continent which
is exposed to the ocean. As they are exposed to the ocean thus moisture availability is there. In the
dry season, the forest biome is getting its water supply from underground water.]
• [* Adaptation by trees to withstand dryness- Leaves are waxy to prevent transpiration loss, Roots
go deep, and Trees are shrubs to minimize the surface area]
• Index plant- Olive, Oak, Cork, etc
• In this biome, a lot of deforestation happened so there are Secondary succession created forests.

TAIGA FOREST BIOME (07:52 PM)

• Climate- A Siberian type of climate
• Climate characteristics- Winter temperature goes around -65 degrees, Very short summer of 3
months, Very short cool summer, Rainfall is very little, and that too in summer, evaporation and
Transpiration is very less and thus evergreen forests are found.
• Adaptation by trees- Leaves are needle-shaped and trees are coniferous.
• 1000s of hectares of one species is found which is called "Pure Strand". These are softwood.
• Index species- Spruce, Pine, Fir, and Larch.
• Region- Siberia, Northern Canada, Northern Part of Europe (Norway, Finland), Alaska.

New Section 3 Page 3

 • Boreal Forest- Taiga forest in the Northern part of the USA and Russia (Siberia) and western
Europe is called the Boreal forest.
• Eastern Siberia's boreal forest is Larch dominated Whereas Western Siberia, Central Siberia,
and the Rest of other Boreal forest is Spruce, pine, and Fir dominated.

• Ground-level vegetation is very weak. Leaves are very waxy and they can't decompose easily as the
soil bacteria are very few.
• [* If the leaves are broken down then it would have released non-organic compounds and it would
have supported the ground-level vegetation. But here the decomposition is not happening]
TUNDRA FOREST BIOME (08:01 PM)
• Arctic Tundra- Polar regions
• Alpine Tundra- The same type of climate in the high altitude of Tall Mountains. For Example-
Mount Kilimanjaro at the equator has a tundra type of climate at the higher slopes.
• Vegetation- Mosses and Lichens only. These do not have true plants.
• Primary producers= Mosses and Algae part of Lichen.
• Herbivores- Lemmings, Musk oxen, Caribou, Reindeer.
• Higher Animals- Arctic foxes, wolves, Humans, and Polar bears.
• In Alpine Tundra, At 2900-3500 meters coniferous forests are found in the Himalayas, At 4500-
meter heights the Alpine tundra are found (Mosses and Lichens).
GRASSLAND BIOMES (08:09 PM)
• Tropical Grassland- These are part of the Savanah setting (10-20 degrees N/S).
• Savanah Forest Biome (10-20 Degrees )
• Climate characteristics- Rainfall in Summer, Warm Winters, Hot summers, Alternate Wet and Dry
season.
• Biome characteristics- A lot of grass is present along with Shrubs as trees. The grass is dominant
and the trees are less.
• Trees- Acacia species, Wild date.
• Grass- Grass is very tall (Elephant Grass), Coarse grass is not eatable by livestock.
• Region- Australia, Africa, South America (Llanos in Venezuela & Colombia and Campos in Brazil
and Argentina)

New Section 3 Page 4

• Tropical Grassland Biome
• Grassland biome- Coarse, Thorny, and Shrubs are trees
• This is also called Parkland, Bushveld as trees are few and scattered and Grass is more.

• Climax/ Index species- Acacia.

• African Savannah- It has special trees called Baobabs. It stores water in its Trunk.

• Temperate Grassland Biome (Sub-tropical to Middle latitude) (25-30 N/S)

• Characteristics- Cool winters, Warm Summer with Sub humid to semi-arid rain-like conditions
• No trees at all, Grass is soft and edible by livestock, Grass is evergreen, Grass is dominant
• Examples- Steppes grassland (Kazakhstan and Russia), Prairies of North America, Pampas in
Argentina and Uruguay, Velds in South Africa, and Downs in Australia (Basin of Murray and
Darling).
• Climax vegetation- Grass
• Index grass- Herb (Non -woody, soft stem, some are flowering), Forb (Broader leaves, Non-
woody, Flowering, Soft stems), Grass (Non-woody, Leaves grow directly from the stem and not
from the branches of the stem, they curl around the stem).
• Grass is of two species i.e. Alpha-Alpha, and Lucerne.

New Section 3 Page 5