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Cal Poly Pomona


Tropical Rainforest

In the rainforest, it rains, throughout the year. Tropical rainforests don’t hold the world records for amounts of rainfall, but they make up for it in consistency. In these lowland forests, there may be seasonal variation, but it always rains.


Tropical Dry Forest

Unlike the rainforest, tropical dry forests have definite wet and dry seasons. During the wet season, a dry forest may be as wet as a rain forest, but during the dry season, it can be as dry as a desert. In these forests, plants and animals must have adaptations to deal with these seasonal changes in precipitation.


Cloud Forest

Cloud forests are found on the sides of tropical mountains, literally where the clouds hit the mountain. Even though there may not be as much rainfall as a rainforest, the trees trap the moisture of the clouds (they look like fog when you are in them), which drops to the ground. Cloud forests are “self-watering”. Some cloud forest species are found in the rainforest, or have close relatives there, but others are found nowhere else on earth.


Human Impacts

Tropical forests are as much shaped by their vegetation as by their climate, so removing the vegetation to grow crops or mine for minerals often changes the forest forever: The plants, which contain most of the nutrients, are removed or burned, and the shallow, nutrient-poor soils are easily eroded. Without the daily transpiration of millions of gallons of water by the original plants of the forest, the area becomes more arid. In some cases, after only a decade the land is no longer useful for agriculture (having lost its topsoil and fertility), and it reverts to a weedy tropical scrub. Much of the land in the tropics consists of these human-degraded landscapes.