Tropical Rainforests and Mangroves

Vocabulary flashcards covering key terms on the distribution, characteristics, and adaptations of tropical rainforests and mangroves.

Tropical Climate

Climate within the tropics, marked by consistently high temperatures and heavy year-round rainfall (about 2,000–4,500 mm).

Tropical Rainforest

Dense, evergreen forest found near the Equator that thrives under high heat and rainfall.

Mangroves

Salt-tolerant plant community growing in coastal, sheltered, tropical zones.

Natural Vegetation

Plant life that develops without human interference in a particular area.

Evergreen

Plants that retain green leaves throughout the year, replacing them continuously.

Vertical Structure

The layered arrangement of plants in a rainforest: emergent, canopy, and undergrowth layers.

Emergent Layer

Topmost rainforest layer formed by trees over ~30 m tall rising above the canopy.

Canopy Layer

Thick, near-continuous layer of interlocking tree crowns (~20–30 m) that blocks most sunlight.

Undergrowth Layer

Lowest rainforest layer of shade-tolerant shrubs and seedlings receiving little sunlight.

Broad Leaves

Large-surface-area leaves that maximise sunlight absorption for photosynthesis.

Waxy Leaves

Leaves coated with a glossy layer to reduce water loss in hot, humid conditions.

Drip Tips

Narrow, downward-pointing leaf ends that shed rain quickly, preventing fungal growth.

Buttress Roots

Large above-ground roots that support tall rainforest trees on shallow, nutrient-rich soil.

Salinity

The amount of dissolved salt in water; higher in coastal mangrove environments.

Horizontal Zonation

Side-to-side banding of mangrove species according to tidal flooding and salinity levels.

Salt-secreting Leaves

Mangrove adaptation where excess salt is excreted onto leaf surfaces and washed away.

Salt-excluding Roots

Roots that block salt uptake, allowing mangroves like Bruguiera to take in fresher water.

Aerial Roots

Roots that project above the soil or water to absorb oxygen and stabilise the plant.

Pencil Roots

Slender, vertical aerial roots of Avicennia that rise ~20 cm above the mud for air.

Cone Roots

Thick, conical aerial roots of Sonneratia that can reach 1.5 m, aiding gas exchange.

Prop Roots

Curved roots from Rhizophora trunks/branches that brace the tree and help it breathe.

Knee-bend Roots

Bruguiera roots that arch above the surface before re-entering the soil, aiding aeration.

Adaptations

Special features evolved by plants to survive and reproduce in specific environments.

Mean Annual Temperature

Average of a location’s monthly temperatures over a year; high in tropical climates (~26–28 °C).

High Annual Rainfall

Total yearly precipitation typical of the tropics, often exceeding 2,000 mm.

Equator

0° latitude line encircling Earth; regions nearby host most tropical rainforests.

Tropic of Cancer

23.5° N latitude; northern boundary of the tropics.

Tropic of Capricorn

23.5° S latitude; southern boundary of the tropics.

Sheltered Environments

Calm coastal areas (e.g., river mouths, behind islands) where mangroves establish.

Competition for Sunlight

Struggle among rainforest plants to access light, driving tall growth and layered structure.