A geographic area with an altitude of 400 metres has the following characteristics: [Temperature and rainfall data showing ~31°C max, ~21°C min, and 51-198mm rainfall throughout year] If this geographic area were to have a natural forest, which one of the following would it most likely be?

Answer: (d) Tropical rainforest

Warm all year (21–31 °C), small range and rain in every month (even the driest has ~5 cm) at low altitude = tropical rainforest.

The idea

To read a climate table, ask two questions in order. First: is it warm all year? If the coolest month is above about 18°C, the place is tropical. Second: is there a dry season? If every month has good rain, the forest is evergreen rainforest; if some months are dry, it is monsoon forest or savannah.

Lowest temperature about 21°C → tropical → Driest month still gets about 5 cm → no dry season → Altitude only 400 m → not a mountain forest → Tropical rainforest

Why the others are wrong

(a) Temperate conifers need cold winters; here the minimum stays above 20 °C.

(b) At 400 m it is too low for montane forest.

(c) Temperate forests have cold winters.

The trap

Read the driest month. If even it gets rain, there is no dry season — so it is not monsoon or deciduous forest.

Also know

Tropical rainforests occur in the Amazon basin, Congo basin and parts of Southeast Asia. In India, examples occur in the Western Ghats, North-East and Andaman and Nicobar Islands. Epiphytes, such as many orchids, grow on trees for support without taking food from them. Lianas are woody climbers that reach sunlight through the canopy.