Water and nutrient cycles in the rainforest ecosystem

Rainforest nutrient and water cycle

The rainforest ecosystem has a distinctive water and nutrient cycle due to:

• high convectional rainfall
• high levels of humidity
• abundant vegetation
• nutrient-rich but shallow soil

Rainforest water cycle

The roots of trees, plants and shrubs take up water from the soil. The rain is intercepted by trees as it falls. As the temperature in the rainforest increases during the day, it causes the water to evaporate into the atmosphere.

This water vapour cools, condenses and forms clouds to make the next day's rain. This is known as convectional rainfall. The whole process is repeated daily and the cycle continues.

Rainforest nutrient cycle

The warm, damp conditions on the forest floor and the abundance of insects enables the rapid breakdown of dead leaves and plant material. This humus provides nutrients that are easily absorbed by plant roots. Because of the abundance of rainforest vegetation, nutrients are used up quickly.

This cycle is continuous as long as deforestation does not occur. Unfortunately, if the protective canopy (umbrella) of vegetation is removed, the soil quickly becomes infertile as nutrients are leached out of the soil, and the topsoil is easily washed away into rivers by heavy rainfall.