Asia: Climate and Natural Vegetation | ICSE Class 8 Geography Notes

This note covers Asia’s climatic contrasts, controls of temperature and rainfall, monsoon winds, equatorial forests, deciduous and thorn vegetation, temperate regions, taiga and tundra, mountain vegetation, wildlife, and the contrasting environments of Ladakh and the Ganga-Brahmaputra basin.

What links Asia’s climate and natural vegetation?

Weather, climate and plant communities

Weather is the condition of the atmosphere at a particular time. The atmosphere is the layer of air surrounding Earth. Climate describes average weather conditions over a longer period. A rainy afternoon describes weather; a recurring pattern of wet summers and dry winters describes climate.

Natural vegetation is a plant community that has remained undisturbed for a long time, allowing its species to adjust to local climate and soil. A species is a particular kind of organism. Planted orchards and cultivated fields must therefore be distinguished from natural plant communities.

Definition: Precipitation is water falling from the atmosphere, including rain and snow. Humidity refers to water vapour, or water in its gaseous form, present in the air.

Asia is the world’s largest continent. Its natural environments include hot, wet regions, seasonally rainy regions, dry interiors, high mountains and very cold northern lands. These contrasts help explain why one continent contains dense forests, open grasslands and low-growing vegetation.

Reading the relationship

Temperature, the degree of hotness or coldness, and available moisture help determine what can grow. Warm conditions with abundant rainfall support different vegetation from conditions with severe cold or very little rainfall. Soil conditions also matter, so rainfall alone does not explain every local difference.

Vegetation names describe different features. Evergreen forests retain a green appearance throughout the year because their trees do not all shed leaves at one fixed time. Deciduous trees shed their leaves seasonally. Coniferous trees are cone-bearing trees, including pine and fir.

Wildlife means animals living in their natural surroundings. To study a region clearly, connect its location with its temperature, rainfall, plants and animals. Keep natural vegetation separate from crops: both respond to environmental conditions, but crops are deliberately cultivated by people.

Which factors explain the climatic contrasts across Asia?

Latitude and altitude

Latitude is angular distance north or south of the Equator. The Equator is the imaginary line halfway between the poles. Equatorial means near the Equator. Asia includes equatorial environments as well as cold northern regions. Moving between these regions means moving between very different temperature conditions.

Altitude means height above sea level. Temperature decreases with increasing height, so mountain places can be much cooler than nearby lowlands. Latitude and altitude are different controls: a mountain can have cold conditions without being close to the northern polar region.

The Himalayas illustrate the importance of relief, meaning the shape and height of the land surface. They act as a climatic divide, shielding the Indian subcontinent from cold northern winds and forcing moisture-bearing monsoon winds to release rainfall within the subcontinent.

Distance from the sea and mountain barriers

Water heats and cools more slowly than land. Coastal areas consequently experience the sea’s moderating influence, which reduces temperature extremes. Interiors far from the sea can have stronger seasonal contrasts. Mumbai and the Konkan coast contrast in this respect with inland Delhi, Kanpur and Amritsar.

A mountain barrier also affects rainfall. Its windward side faces the incoming wind; its leeward side lies away from that wind. Moist air forced up a mountain cools and releases rain, leaving less moisture available on the other side.

These controls operate together. Ladakh’s cold, dry environment, for example, involves both high altitude and shelter from rain-bearing winds. Explaining a climate therefore requires more than identifying whether a place lies in northern or southern Asia.

How do winds and mountains influence rainfall?

Seasonal winds

Air pressure is the force exerted by the weight of air per unit area. Differences in pressure help produce winds. Land and sea heat and cool at different rates, creating seasonal pressure differences around the Indian subcontinent.

Monsoon refers to the seasonal reversal in wind direction and the climate associated with it. Tropical refers to the warm region between the Tropic of Cancer and the Tropic of Capricorn. The hot monsoonal climate is prevalent in south and southeast Asia. Heavy rainfall in tropical monsoon climates occurs mostly in summer, while winter is dry.

This broad pattern does not remove regional differences. Most parts of India receive rainfall during June to September, but coastal Tamil Nadu receives rain at the beginning of winter. A seasonal wind pattern therefore does not mean identical rainfall timing in every locality.

Note: Different heating of land and sea helps explain seasonal wind changes. No single theory fully explains the monsoon, so this basic relationship should not be treated as a complete explanation of every monsoon feature.

Relief rainfall and the rain shadow

Relief rainfall, also called orographic rainfall, results when a mountain forces moist air upwards. Condensation is the change of water vapour into liquid water. The steps below explain how mountain slopes can receive different amounts of rain.

1. Moist air meets a mountain barrier and is forced to rise on the windward slope.
2. As the rising air expands, its temperature falls and its water vapour condenses.
3. Rain falls on the windward slope, removing some of the moisture carried by the air.
4. Air descends on the leeward side and warms, increasing its capacity to hold moisture and producing drier conditions.

The drier leeward area is called a rain shadow. This explains why two sides of a mountain range need not support equally dense vegetation. Ladakh lies in the Himalayan rain shadow, while windward areas elsewhere can receive much more rainfall.

The link is therefore a chain: relief affects air movement; air movement affects rainfall; rainfall affects the water available for vegetation. Temperature and soil must still be considered alongside that chain.

What characterises the equatorial climate and evergreen forests?

Warmth and rainfall throughout the year

Equatorial climate is the hot, wet climate found near the Equator. In Asia, tropical wet conditions occur in the islands known as the East Indies, the island region of Southeast Asia. Significant rainfall occurs in every month, as afternoon thunder showers.

Temperatures remain uniformly high, and the annual temperature range, the difference between the warmest and coldest monthly mean temperatures, is negligible. A mean is an average. A tropical wet region therefore has much less seasonal temperature variation than a cold continental interior.

Abundant moisture and warmth support tropical evergreen forests. These forests have a dense canopy, the upper cover formed by leaves and branches. They also have large biodiversity, meaning a wide variety of living organisms. Forest structure and climatic conditions must be considered together.

Layers and examples

In India, tropical evergreen forests occur on the western slopes of the Western Ghats, in northeastern hills, and in the Andaman and Nicobar Islands. Their warm, humid environments receive annual precipitation exceeding 200 centimetres. A centimetre, written cm, is a unit of length used to express rainfall depth.

The mean annual temperature in these forest regions is above 22 degrees Celsius. °C means degrees Celsius, the unit used here for temperature. These are conditions for the Indian evergreen forests described here, not a claim that every Asian rainforest has identical measurements.

The vegetation forms layers: shrubs and climbing plants grow nearer the ground, with shorter trees and taller trees above. Some trees reach 60 metres or more. A metre, written m, is a unit of length used here for height.

Rosewood, ebony and mahogany are examples of trees in these forests. There is no fixed time when all trees shed their leaves, flower or bear fruit. The green appearance throughout the year does not mean that individual leaves never fall.

Less rainy parts of these Indian regions have semi-evergreen forests, containing a mixture of evergreen and moist deciduous trees. This transition shows how vegetation changes with moisture conditions even within a broadly warm environment.

How do monsoon climates support tropical deciduous forests?

A seasonal supply of moisture

Tropical deciduous forests are also called monsoon forests. They are the most widespread forests in India. Their setting differs from that of evergreen forests because the availability of water changes more strongly with the seasons.

In dry deciduous forests, trees shed their leaves as the dry season begins. The forest can then appear as open grassland with bare trees. This seasonal appearance should not be confused with permanent absence of trees or with the sparse vegetation of a desert.

On the basis of available water, tropical deciduous forests are divided into moist deciduous and dry deciduous forests. Moist deciduous forests occur in wetter areas, while dry deciduous forests grade towards thorn vegetation at their drier margins.

Rainfall and forest comparisons

The table gives rainfall conditions for Indian forest types. Annual rainfall means rainfall received over a year; all values below are rainfall depths in centimetres. The boundaries describe the stated forest categories and should not be turned into universal limits for every location in Asia.

Moist deciduous forests occur along Himalayan foothills in northeastern states, on eastern slopes of the Western Ghats and in Odisha. Their trees include teak, sal and shisham. Dry deciduous forests occur in rainier peninsular areas and the plains of Uttar Pradesh and Bihar.

The Ganga-Brahmaputra plains provide a regional example of tropical deciduous vegetation. Teak, sal and peepal occur there, while thick bamboo groves are common in the Brahmaputra plain. A monsoon region can therefore contain varied vegetation rather than one uniform forest.

Why are some Asian regions deserts or grasslands?

Dryness is the essential distinction

A desert is a very dry region with scarce vegetation and extreme temperatures, which may be high or low. Deserts are not defined by heat alone. Ladakh is an Asian cold desert, demonstrating why dryness and temperature must be considered separately.

In middle latitudes, dry climates occur in continental interiors where moisture-bearing sea winds do not reach. Such areas are often surrounded by mountains. Distance from the sea and mountain barriers can therefore work together to restrict the supply of moisture.

Semi-arid means partly dry. Subtropical means adjoining the tropical zone. A steppe is an open grassland associated with semi-arid conditions. Subtropical steppe regions receive slightly more rainfall than deserts, enough to support sparse grassland. This is a relative difference, not a statement that steppes have abundant water.

Thorn vegetation and regional contrasts

Indian tropical thorn forests occur where annual rainfall is below 50 cm. They include grasses and shrubs in semi-arid parts of Punjab, Haryana, Rajasthan, Gujarat, Madhya Pradesh and Uttar Pradesh. A shrub is a woody plant smaller than a tree, commonly branching near the ground.

Plants remain leafless for most of the year, giving the vegetation a scrub-like appearance. Trees and shrubs include babool, ber, khair, neem and khejri. Low rainfall helps explain this vegetation, but grazing can also affect how much plant cover remains.

Do not transfer every thorn-forest feature to a cold desert. Ladakh has scanty patches of grasses and shrubs, with willows and poplars in valleys. Its cold, high-altitude setting is different from that of tropical thorn vegetation.

The comparison also clarifies why grassland and desert should not be treated as identical. Both can be relatively dry, but the amount of moisture available supports different degrees of plant growth. Describing a region requires its rainfall conditions, temperature setting and actual vegetation.

How do Asia’s temperate climates differ from one another?

Eastern and interior regions

Temperate climates occur in middle latitudes, between tropical and polar regions. Warm temperate climates generally have warm summers and mild winters. The word “temperate” therefore describes a broad group, not one rainfall pattern shared by every region.

The north Indian plains and the interior plains of southern China include a humid subtropical type with dry winters and hot summers. Subtropical means adjoining the tropical zone. Southern and eastern China and southern Japan also include humid subtropical areas with rainfall throughout the year.

In those latter regions, summer thunderstorms and winter rainfall occur. Their seasonal rainfall pattern differs from a strongly winter-dry monsoon pattern. Locating a place in eastern Asia is therefore only a starting point; the timing and amount of rain still need examination.

Mediterranean and colder continental patterns

Mediterranean climate occurs around the Mediterranean Sea and has hot, dry summers with mild, rainy winters. Its rainfall rhythm differs from tropical monsoon regions, where heavy rain falls mostly in summer. The season of rainfall matters as much as the annual total.

The following figures describe the humid subtropical climate without a dry season, found in southern and eastern China and southern Japan among other world regions. They are regional climate characteristics, not readings from an individual weather station.

Farther into the cold continental climates of northeastern Asia, winters become much more severe. Many locations experience temperatures below freezing for up to seven months in a year. Freezing point is the temperature at which water freezes, 0°C under ordinary conditions.

These contrasts prevent an important error: mild winter conditions in one temperate type cannot be applied to the whole of northern or eastern Asia. A useful comparison includes summer temperature, winter severity and the season when precipitation occurs.

What distinguishes taiga from tundra in northern Asia?

The northern forest belt

Taiga is the broad belt of coniferous forest in northern Asia. It belongs to a cold environment but remains a forest. Cone-bearing trees such as pine, spruce and fir are associated with this vegetation, unlike the low-growing plants characteristic of tundra.

Cold snow-forest climates occupy large continental areas of the Northern Hemisphere, including Asia. The Northern Hemisphere is the half of Earth north of the Equator. Winter severity increases towards higher northern latitudes, and the period suitable for plant growth becomes more restricted.

Northeastern Asia includes a cold climate with dry winters. Precipitation occurs in summer, while winter temperatures become extremely low towards the pole. This seasonal pattern differs from the warm, moist conditions supporting equatorial evergreen forests.

Low-growing vegetation of tundra

Tundra is the cold-region vegetation of low-growing mosses, lichens and flowering plants. Mosses are small, non-flowering plants. Lichens are small, plant-like growths often seen on rocks or bark. These organisms form low vegetation rather than a tall forest canopy.

Permafrost is permanently frozen ground beneath the surface. In tundra regions, the short growing season and waterlogging support only low-growing plants. Waterlogging means that the ground is saturated with water. Very long daylight during summer does not remove these restrictions on growth.

Both regions are cold, but calling them the same vegetation type would hide their central difference. Taiga has forest trees; tundra has low plant growth. Similarly, tundra is not identical to a permanent ice cap, where conditions are still more severe.

Low-growing tundra vegetation also occurs at high mountain altitudes. This provides a second connection between temperature and vegetation: increasing height can produce some vegetation changes comparable to those encountered towards colder northern regions.

How does vegetation change with altitude in the Himalayas?

From foothills to higher slopes

Montane vegetation means vegetation associated with mountains. As altitude increases, falling temperature produces a corresponding change in plant communities. The Himalayas show a succession from tropical vegetation towards tundra vegetation at higher levels.

Deciduous forests occur in the foothills. Higher slopes support temperate forests, including broad-leaved trees such as oak and chestnut. Broad-leaved trees have wide leaves, in contrast with the narrow needle-like leaves of many coniferous trees.

Pine forests also develop at some elevations, while deodar grows mainly in the western Himalayan region. Still higher areas include forests and pastures of the alpine zone, the high mountain belt. A pasture is land with vegetation on which animals graze.

Silver fir, juniper, pine, birch and rhododendron occur at high elevations. At higher altitudes, mosses and lichens form part of the tundra vegetation. The sequence should be understood as a response to changing conditions, not as one tree species replacing another at every identical height.

Slope and moisture also matter

The southern Himalayan slopes have thicker vegetation because they receive relatively higher precipitation than the drier north-facing slopes. This means altitude alone cannot explain every vegetation difference. The direction a slope faces and its exposure to moisture-bearing winds also matter.

Compare two questions: “How high is the slope?” and “How much moisture reaches it?” The first concerns the temperature change with altitude. The second concerns the supply of water. Together they help explain why mountain vegetation is varied rather than uniform.

The Ganga-Brahmaputra basin includes coniferous trees such as pine, deodar and fir in parts of Uttarakhand, Sikkim and Arunachal Pradesh, where slopes are steep and climate is cool. Within one large basin, plains and mountain slopes can therefore support very different vegetation.

Mountain vegetation provides a useful connection between the chapter’s main ideas. Relief influences temperature and rainfall; these conditions influence plants; and the vegetation forms part of the environment available to wildlife and grazing animals.

Case study: why is Ladakh a cold desert?

Height, shelter and dryness

Ladakh is a cold desert in the Great Himalayas. The Karakoram Range lies to its north and the Zanskar mountains to its south. Several rivers cross the region, with the Indus the most important among them.

Its altitude varies from about 3,000 m at Kargil to more than 8,000 m in the Karakoram. High altitude explains the extremely cold conditions. Its position in the Himalayan rain shadow explains why the region receives little rainfall, as low as 10 cm annually.

The environment combines cold, dry air with intense sunlight. The term aridity means dryness caused by a shortage of moisture. Aridity restricts vegetation even where sunshine is strong; sunlight alone cannot provide the water plants need.

The map labels the Ladakh Range and shows rivers in blue, including the Indus and Shyok, with the Siachen Glacier. Kargil, Leh and Zoji La are labelled, and a north arrow indicates direction.

See Fig. 7.4 in your NCERT textbook

Vegetation and wildlife

Vegetation is sparse because of high aridity. Scanty patches of grasses and shrubs provide grazing, while groves of willows and poplars occur in valleys. These valley trees do not mean that dense forest covers the whole region.

Ladakh’s animals include wild goats, wild sheep and yak. Birds include robins, redstarts, Tibetan snowcock, raven and hoopoe; some are migratory. Migratory birds move between regions seasonally. The qualification matters: it does not describe every bird listed.

The case study demonstrates the difference between heat and dryness. A region can be a desert even when it is very cold. It also shows why a climate explanation needs several factors: altitude contributes to cold, while mountain shelter contributes to low rainfall.

When connecting climate and vegetation here, retain the local exceptions. Sparse plant cover is the broad pattern, but valleys support trees. The correct description includes both the general dryness and the specific places where more vegetation occurs.

Case study: how does the Ganga-Brahmaputra basin show environmental variety?

A monsoon region with contrasting landforms

A river basin is the area drained by a river and its tributaries. Tributaries are smaller rivers joining a larger river. The Ganga-Brahmaputra basin includes plains, Himalayan mountains and foothills, and the Sundarbans delta.

A delta is a depositional landform near a river’s mouth, where sediment carried by the river accumulates. A river’s mouth is where it enters another body of water. These low-lying environments differ from steep mountain slopes within the same basin.

The basin has a monsoon climate, with rains from mid-June to mid-September. Summers are hot and winters cool. Its vegetation varies with landforms, so one climate label does not fully describe the plant cover of every part.

The map shades the basin and shows the Ganga, Brahmaputra and tributary rivers in blue. It labels the Ganga and Brahmaputra rivers, Nepal, Bhutan, Bangladesh and the Bay of Bengal, and marks the Tropic of Cancer, with a north arrow and a distance scale.

See Fig. 6.8 in your NCERT textbook

Vegetation and animal distribution

The plains have tropical deciduous trees, including teak, sal and peepal. Thick bamboo groves are common in the Brahmaputra plain. The delta supports mangrove forests, meaning forests adapted to tidal coastal environments.

Cooler mountain areas in parts of Uttarakhand, Sikkim and Arunachal Pradesh have coniferous trees such as pine, deodar and fir. Thus, deciduous forest, bamboo, mangroves and conifers belong to different settings within the basin rather than one identical vegetation cover.

Elephants, tigers, deer and monkeys are common in the basin. The one-horned rhinoceros occurs in the Brahmaputra plain. Bengal tigers and crocodiles occur in the delta area. These examples link wildlife with particular regional environments.

Compared with Ladakh, this basin demonstrates a wetter monsoon environment with varied vegetation. The comparison does not require treating every part of the basin as equally wet or equally forested. Climate supplies the broad pattern, while relief and local water conditions help explain the differences within it.

Glossary

• Climate — The average pattern of weather conditions in an area over a longer period of time.
• Natural vegetation — A plant community left undisturbed long enough for its species to adjust to local climate and soil.
• Precipitation — Water falling from the atmosphere to the ground, including rain and snow.
• Latitude — The angular distance of a place north or south of the Equator.
• Altitude — The height of a place above sea level, affecting its temperature.
• Relief — The shape and height of the land surface, including mountains and lowlands.
• Monsoon — The seasonal reversal in wind direction and the climate associated with this reversal.
• Rain shadow — The drier area on the leeward side of a mountain barrier.
• Evergreen forest — A forest appearing green throughout the year because trees do not all shed leaves at one fixed time.
• Deciduous forest — A forest characterised by trees that shed their leaves during a particular season.
• Steppe — An open grassland associated with semi-arid conditions and limited moisture availability.
• Taiga — The broad belt of cold-region coniferous forest extending across northern Asia.
• Tundra — Low-growing vegetation of cold regions, including mosses, lichens and flowering plants.
• Permafrost — Permanently frozen ground beneath the surface, characteristic of tundra environments.
• River basin — The area drained by a river together with its tributary rivers.

Common errors and misconceptions

• Misconception: Asia has one climate because it is one continent. Correct: Its climate varies with latitude, altitude, distance from the sea, winds and relief. Equatorial warmth, monsoon seasonality and northern cold cannot be treated as the same environment.
• Misconception: Every desert must be hot. Correct: Deserts have very low rainfall and scarce vegetation, but they can be hot or cold. Ladakh is a cold desert with high altitude and a Himalayan rain-shadow location.
• Misconception: Monsoon means continuous summer rain everywhere. Correct: It refers to seasonal wind reversal. Heavy rain occurs mostly in summer in tropical monsoon climates, but regional variations exist, including winter-season rainfall along coastal Tamil Nadu.
• Misconception: Evergreen trees never lose leaves. Correct: Evergreen forests remain green because their trees do not all shed leaves at one fixed time. A year-round green appearance does not imply that individual leaves remain permanently attached.
• Misconception: Taiga and tundra are interchangeable names. Correct: Taiga is coniferous forest, while tundra has low-growing mosses, lichens and flowering plants. Severe cold is shared, but the vegetation structure is different.
• Misconception: Latitude explains every cold place. Correct: Altitude also matters. Mountain temperatures fall with increasing height, helping explain cold conditions in Ladakh and changes in vegetation up Himalayan slopes.
• Misconception: One rainfall number determines vegetation everywhere. Correct: Temperature, seasonal moisture availability, soil and relief also matter. Rainfall bands describing Indian forests must not be treated as universal boundaries for every Asian location.

Exam-style questions with model answers

Q1. Weather means atmospheric conditions at a particular time; climate means average weather over a longer period. Classify a rainy afternoon and a recurring pattern of wet summers with dry winters, giving a reason for each. [2 marks]

1. A rainy afternoon describes weather because it concerns atmospheric conditions during a particular short period.
2. Recurring wet summers and dry winters describe climate because they form a longer-term seasonal weather pattern.

Q2. Water heats and cools more slowly than land, the sea moderates coastal temperatures, and inland areas experience stronger seasonal contrasts. Using these facts, explain the temperature contrast between a coast and an inland area in three points. [3 marks]

1. Water changes temperature more slowly than land, so the sea does not heat or cool as quickly as the neighbouring land surface.
2. A coastal area experiences the moderating influence of the sea, which reduces the extremes of temperature affecting that area.
3. An inland area is farther from this influence and can therefore experience stronger contrasts between the temperatures of different seasons.

Q3. Moist air rises over a mountain, expands and cools, releases rain on the windward side, then descends and warms on the leeward side. Explain the formation of a rain shadow in four stages using this information. [4 marks]

1. The mountain blocks the movement of moist air and forces it to rise along the slope facing the incoming wind.
2. During ascent, the air expands and cools, allowing water vapour to condense rather than remain entirely in gaseous form.
3. Rain falls on the windward slope, removing some of the moisture that the incoming air had been carrying.
4. On the leeward side, descending air warms and can hold more moisture, producing the drier conditions called a rain shadow.

Q4. Indian evergreen forests receive over 200 cm annual precipitation, remain green and have dense vegetation; deciduous forests receive 70 to 200 cm; moist deciduous forests receive 100 to 200 cm; dry deciduous forests receive 70 to 100 cm and shed leaves as the dry season begins; thorn forests receive less than 50 cm and contain grasses and shrubs. Write five comparisons linking each forest category to its moisture or vegetation feature. [5 marks]

1. Evergreen forests occupy the highest rainfall category, receiving over 200 cm annually and maintaining a green appearance throughout the year.
2. Tropical deciduous forests occupy the broader rainfall band from 70 to 200 cm, which contains both the moist and dry deciduous categories.
3. Moist deciduous forests occupy the wetter part of the deciduous range, receiving 100 to 200 cm of rainfall in a year.
4. Dry deciduous forests receive 70 to 100 cm annually, and their trees shed leaves when the dry season begins, changing the forest’s appearance.
5. Thorn forests occupy the driest category, below 50 cm annually, and their vegetation includes grasses and shrubs rather than the dense evergreen structure.

Q5. Taiga is coniferous forest with pine, spruce and fir. Tundra has mosses, lichens and low flowering plants; its subsoil is permanently frozen, and its short growing season and waterlogging restrict growth. Distinguish the two regions and explain tundra’s low vegetation in four points. [4 marks]

1. Taiga is a forest environment with cone-bearing trees, represented by pine, spruce and fir.
2. Tundra has low-growing plant cover, represented by mosses, lichens and flowering plants, rather than the forest trees of taiga.
3. Permanently frozen subsoil is a feature of the tundra environment and forms part of the severe conditions in which its plants grow.
4. The short growing season and waterlogging restrict growth, explaining why tundra supports low plants rather than a tall forest canopy.

Q6. Temperature decreases with height, and a rain shadow is sheltered from much rain-bearing moisture. Ladakh has very high altitude, lies in the Himalayan rain shadow, receives rainfall as low as 10 cm annually, has sparse grasses and shrubs, and supports willow and poplar groves in valleys. Explain its cold-desert environment in five points using only these facts. [5 marks]

1. Very high altitude helps explain Ladakh’s cold conditions, since temperature falls with increasing height and high mountain places are colder than lower places.
2. Its location in the Himalayan rain shadow places it in an area sheltered from much of the moisture carried by rain-bearing winds.
3. Rainfall can be as low as 10 cm annually, so Ladakh suffers a severe shortage of moisture as well as cold conditions.
4. Sparse grasses and shrubs reflect the restricted plant cover of this dry environment; the vegetation is not described as a continuous dense forest.
5. Willow and poplar groves in valleys show local variation within the cold desert, so the broad description of sparse vegetation does not mean complete absence of trees.

Q7. The Ganga-Brahmaputra plains have deciduous teak, sal and peepal; the delta at the river mouth has mangroves; cool, steep mountain areas have coniferous pine, deodar and fir. Explain three links between landforms and vegetation using these examples. [3 marks]

1. The plains support tropical deciduous trees, with teak, sal and peepal showing the vegetation associated with the lower plain environment.
2. The delta supports mangrove forests, identifying a different plant community in the river-mouth environment rather than the same trees throughout the basin.
3. The cool, steep mountain areas support coniferous trees such as pine, deodar and fir, demonstrating vegetation differences between the plains and higher slopes.

Q8. Tropical monsoon climates receive heavy rain mostly in summer and have dry winters, whereas Mediterranean climates have hot, dry summers and mild, rainy winters. State two contrasts in the timing of rainfall. [2 marks]

1. Tropical monsoon climates receive their heavy rainfall mostly in summer, while Mediterranean summers are dry.
2. Tropical monsoon winters are dry, whereas Mediterranean winters are rainy.

Key takeaways

• Asia’s climatic variety reflects latitude, altitude, distance from the sea, seasonal winds and the effects of mountain barriers.
• Natural vegetation responds to temperature, available moisture and soil; cultivated crops and planted orchards are a separate category.
• Equatorial climates support dense evergreen forests, while seasonal moisture patterns help distinguish monsoon forests from wetter evergreen regions.
• Relief rainfall makes windward slopes wetter and produces drier rain-shadow conditions on the leeward side of mountain barriers.
• Deserts can be cold as well as hot; Ladakh combines high altitude with low rainfall in the Himalayan rain shadow.
• Taiga is coniferous forest, whereas tundra has low-growing plants restricted by a short growing season, frozen subsoil and waterlogging.
• Himalayan vegetation changes with altitude, but slope exposure and rainfall also affect the density and type of plant cover.
• The Ganga-Brahmaputra basin contains varied vegetation and wildlife because its plains, mountains and delta provide different environmental settings.

Test yourself

What is the difference between weather and climate?

Weather describes atmospheric conditions at a particular time; climate describes the average weather pattern over a longer period.

Why does a coastal location tend to have smaller temperature extremes?

The sea moderates nearby temperatures because water heats and cools more slowly than land.

Which mountain slope faces the incoming wind?

The windward slope faces the incoming wind; the leeward slope lies on the other side.

Does an evergreen forest keep every individual leaf permanently?

No. It remains green because its trees do not all shed leaves at one fixed time.

How does steppe rainfall compare with desert rainfall?

Subtropical steppes receive slightly more rainfall than deserts, enough to support sparse grasslands.

What distinguishes taiga vegetation from tundra vegetation?

Taiga has coniferous forest trees, while tundra supports low-growing mosses, lichens and flowering plants.

Which two factors explain Ladakh’s cold and dry setting?

High altitude helps explain its cold; its Himalayan rain-shadow position helps explain its dryness.

Where is the one-horned rhinoceros found within the Ganga-Brahmaputra basin?

It occurs in the Brahmaputra plain, while Bengal tigers and crocodiles occur in the delta area.