World Biomes

Tropical deciduous forest

Introduction

• Tropical deciduous forests are like tropical rain forests, but have a pronounced dry season which causes the trees to lose their leaves.  This type of forest is found on the fringes of the tropical rain forests. As the climate gets drier, tropical deciduous forests grade into savanna, and, eventually, grasslands.

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Distribution

Tropical deciduous forests grow in seasonally dry areas of the tropics. These forests occur mainly in India, the Myanmar-Vietnam-southern coastal China region, eastern Brazil, smaller areas in South and Central America north of the Equator, the West Indies, south-eastern Africa, and northern Australia.

Distribution

Dry Wet

Warm desertTropical grassland

SavannaTropical

deciduousforest

Tropical rainforest

Climate

• Well defined dry (winter) and wet (summer) season

• Rainfall of 700-3000mm

• Like in the tropical rainforest climate, temperatures remain high all year

Soil

Soil is richer in nutrients than in tropical rainforest because trees drop down leaves and the trees grow more sparsely.

Moist deciduous forests

• Moist deciduous forests are found in tropical regions where both rainy and dry seasons occur during the year. These forests are different from tropical rain forests in that the trees are not as tall and have rather thick bark. In the first month of the dry season, the leaves fall. New leaves sprout just before the rainy season begins.

Dry deciduous forests

• Dry tropical deciduous forests occur in regions that have long, severe dry seasons, such as the savannas (grasslands) of Africa. The tallest trees are shorter and more twisted than those in a temperate forest, and the bark is thicker. Some trees may store water in their trunks. During the dry season, the trees lose their leaves, and many produce flowers. Some, such as wattle trees in Australia, have adapted by producing thorns instead of many leaves.

Plants

• The trees here are typically not as close together as in the tropical rainforests, so more light can reach the forest floor, especially when the deciduous species have dropped their leaves. The availability of sunlight on the forest floor results in dense undergrowth, which makes walking extremely difficult.

Animals

• Many animals live on trees

• Life on forest floor is more diverse

• Animals are adapted to dry season

People

• Dry tropical forests share many of the problems of the rainforest, in terms of pressures for agricultural development as a consequence of human population pressure. Recovery of these forests after disturbance can take even longer than that of rainforest.

• Monsoon forests are now largely logged out in SE Asia. Dry tropical forests also heavily logged, nearly vanished in Indonesia.