What is the quality of soil in the tropical rainforest?

Answer 1

Soil quality includes several parameters, but it is likely that you are asking about the fertility of tropical rainforest soils, because many other aspects of soil quality are unrelated to the soil's position on the globe.

Soil fertility in tropical rainforest soils is low. This is because of the warm climate and the availability of water, both of which increase microbial activity, chemical reaction times, and the leaching of soluble soil constituents.

The warm, moist environment causes the rapid breakdown of minerals and additions of organic matter (dead leaves and other plant parts, etc.) and then the removal of these breakdown products by living plants and rainwater. Plant nutrients are often locked up as part of soil minerals and soil organic matter. The rainforest environment decomposes these more complex, insoluble substances, and the rapidly growing plants of the rainforest take these nutrients up. Any nutrients not taken up by the plants are then easily washed out of the soil (this is called leaching of nutrients).

The nutrients in a rainforest ecosystem are contained within the plants, rather than the soils. If the plants are harvested and removed, the nutrients go with them.