World Natural Vegetation & Biomes

The Earth’s land surface is covered by a remarkable variety of plant life, from the dense, towering rainforests of the Amazon to the sparse mosses of the Arctic tundra. This pattern of vegetation is not random. It is a direct response to climate, particularly temperature and rainfall.

NDA tests this chapter through grassland name-country matching, vegetation-biome identification, specific plant characteristics, and the relationship between climate and vegetation type. The grassland names and their countries are among the most reliably tested facts in all of World Geography.

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The Relationship Between Climate and Vegetation

Vegetation in any region is determined primarily by: Temperature | Rainfall and moisture | Season length | Soil (itself partly a product of vegetation and climate).

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Biomes from Equator to Pole

Moving from the equator toward the poles, you pass through biomes that mirror the change in climate:

Tropical Rainforest → Tropical Grassland (Savanna) → Hot Desert → Mediterranean Scrubland → Temperate Grassland → Temperate Deciduous Forest → Boreal Forest (Taiga) → Tundra → Ice Desert

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Tropical Rainforest (Selvas)

Location: Equatorial zone: Amazon Basin (South America), Congo Basin (Africa), Southeast Asian islands (Borneo, Sumatra, New Guinea).

Climate: Hot and humid throughout the year. Heavy convectional rainfall almost every afternoon. Extends between 10°N and 10°S.

Characteristics: Dense, multi-layered forest (emergent trees 50–60 m; canopy 25–35 m; understory below) | Evergreen: no dry season to trigger leaf-shedding | Highest biodiversity on Earth.

The name Selvas refers specifically to the Amazon Basin tropical rainforest of South America. [NDA 2012-I]

Characteristic vegetation: Selvas = Epiphytes: [NDA 2014-I | 2015-I]

Epiphytes: plants that grow on other plants for physical support but are not parasitic: orchids, bromeliads, and ferns clinging to tree branches. Lianas: woody climbing vines. Buttress roots: wide flaring roots to provide support in thin tropical soil.

Why tropical rainforests are luxuriant: [NDA 2015-I]

The luxuriant growth is due to (1) hot and wet climate throughout the year and (2) intense sunlight for photosynthesis. Fertile soil is NOT a reason. Tropical rainforest soil is actually nutrient-poor; most nutrients are locked in the living vegetation. When the forest is cleared, soil becomes infertile quickly. Seasonal change is also NOT a reason. There are no seasons in the equatorial zone. [NDA 2015-I]

Maximum biodiversity is in the tropical zone. [NDA 2010-I]

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Tropical Savanna (Tropical Grassland)

Location: Between equatorial rainforest and tropical deserts, approximately 5°–20° latitude in Africa, South America, and Australia.

Climate: Hot throughout the year with distinct wet and dry seasons.

Characteristics: Tall grasses (1–3 metres) with scattered flat-topped trees (acacia in Africa) | fires common in dry season | lies between tropical rainforest and tropical steppes.

Savanna = Grasses and trees. [NDA 2014-I | NDA 2015-I]

Tropophytes: plants in monsoon and savanna regions that adapt to alternating wet and dry seasons. They shed leaves in the dry season and grow them back when rain returns. Monsoon lands = Tropophytes. [NDA 2014-I]

Tropical Grassland Names

Name	Region	Country	NDA Tag
Savanna	Africa	Sub-Saharan Africa	—
Llanos	South America	Venezuela and Colombia	[NDA 2010-II]
Campos (Campo Cerrado)	South America	Brazil	[NDA 2006-I
Gran Chaco	South America	Argentina, Paraguay, Bolivia	—

Campos and Llanos tropical savanna grasslands are found in South America. [NDA 2019-I]

Campo grasslands are in Brazil. [NDA 2006-I]

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Hot Desert Vegetation

Location: Subtropical desert zones: Sahara, Arabian Desert, Thar, Atacama, Australian Desert.

Characteristic vegetation: Xerophytes: plants adapted to survive in extreme drought. Xerophytes thrive in hot and arid conditions. [NDA 2010-I]

Xerophyte adaptations: Deep roots to reach underground water | thick, waxy leaves to reduce water loss | leaves modified into thorns/spines | stem stores water (succulents like cacti) | seeds dormant for years.

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Mediterranean Scrubland

Location: Mediterranean climate zones: Mediterranean basin, California, central Chile, southwestern Australia, southwestern South Africa.

Characteristic vegetation: Sclerophyll: plants with hard, waxy, drought-resistant leaves adapted to hot dry summers and mild wet winters.

Regional names: Maquis/Garrigue (Mediterranean Europe) | Chaparral (California) | Mallee (southwestern Australia) | Fynbos (southwestern South Africa) | Matorral (central Chile).

Cities with sclerophyll natural vegetation: Valparaiso, Cape Town, Lisbon, Perth, Los Angeles, Adelaide.

Cities WITHOUT sclerophyll: Las Vegas (desert) and Queensland (tropical): these are NOT Mediterranean climate zones.

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Temperate Grasslands

Location: Mid-latitude continental interiors: too dry for forests, enough for grasses.

Characteristics: Short to tall grasses; no trees except along rivers | Very fertile soils (chernozem / black earth) | Large seasonal temperature range | Major agricultural regions.

★ IMPORTANT This grassland match list is one of the most repeatedly tested fact sets in NDA World Geography. Memorise all five. [NDA 2010-II | NDA 2012-II | NDA 2019-I]

Name	Region	Country	NDA Tag
Prairies	North America	USA and Canada	[NDA 2010-II]
Steppes	Central Asia / Eastern Europe	Russia, Ukraine, Kazakhstan	—
Pampas	South America	Argentina (and Uruguay)	[NDA 2010-II]
Veld (Veldt)	Southern Africa	South Africa	[NDA 2010-II
Downs	Australia	Southeastern Australia	[NDA 2010-II]
Canterbury Plains	New Zealand	New Zealand	—

NDA 2010-II: Pampas = Argentina | Veld = South Africa | Downs = Australia | Llanos = Venezuela. Answer: A-4, B-3, C-2, D-1.

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Temperate Deciduous Forest

Location: Eastern USA, Western and Central Europe, northeastern China, Japan, southeastern Australia.

Characteristics: Broad-leaved trees that shed leaves in autumn (deciduous) | four distinct seasons | moderate year-round rainfall | rich, fertile soils from leaf litter.

Trees: oak, beech, maple, elm, birch, hickory.

NDA 2024-I identification: High rainfall + temperatures varying cold to mild + deciduous trees (maple, oak, hickory, beechwood) + raccoons, opossums, bats, squirrels = Temperate forest. [NDA 2024-I]

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Boreal Forest (Taiga)

Location: Sub-Arctic belt across Canada, Alaska, Scandinavia, and Russia, the largest land biome on Earth.

Characteristics: Dominated by coniferous trees (cone-bearing, evergreen, needle-leaved) | very short summer (<4 months above 10°C) | long bitterly cold winter | thin acidic soils (podsols) | very little undergrowth.

Trees: Spruce, fir, pine, larch, cedar, deodar. Spruce and Cedar are tree varieties of temperate coniferous forest. [NDA 2016-I]

Taiga = Conifers. [NDA 2015-I]

Growing period = 50–100 days. Very little undergrowth is a characteristic. Coniferous trees are NOT deciduous. They do not shed leaves in autumn.

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Tundra

Location: Arctic regions of Canada, Alaska, Siberia, and Scandinavia, and at high altitude (alpine tundra).

Characteristics: Treeless: the most defining characteristic | Vegetation: mosses, lichens, sedges, low shrubs, dwarf willows | Very short growing season (<2 months) | Permafrost (permanently frozen subsoil) | Low precipitation.

Tundra = Mosses and Lichens. [NDA 2014-I | NDA 2015-I]

Why are there no trees in the tundra? Frozen ice beneath the surface soil (permafrost) restricts root growth. Trees cannot develop deep roots because the frozen subsoil prevents penetration. Cold temperature alone is not the primary cause. [NDA 2011-I]

Belarus does NOT have tundra vegetation. It has temperate forests. Russia, USA (Alaska), and Canada all have tundra.

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Mountain Vegetation

As altitude increases on a mountain, vegetation changes just as it does moving from equator to poles, from forest at the base to tundra-like conditions near the summit. This is called altitudinal zonation or vertical zonation.

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Vegetation Terms: The Key Vocabulary

Term	Definition	Climate / Biome	NDA Tag
Epiphyte	Grows on other plant for support (NOT parasitic)	Tropical rainforest (Selvas)	[NDA 2014-I
Tropophyte	Adapts to wet AND dry seasons; sheds leaves in dry season	Monsoon and Savanna	[NDA 2014-I]
Xerophyte	Adapted to drought; hot and arid conditions	Hot Desert	[NDA 2010-I]
Sclerophyll	Hard, waxy drought-resistant leaves	Mediterranean
Orophyte	Grows only in mountainous environment	Mountain	[NDA 2013-II]
Geophyte	Stores nutrients in bulbs/tubers/rhizomes underground	Temperate zones	—
Bryophyte	Non-vascular plants: mosses and liverworts	Tundra and others	—

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