Tropical Rain Forests: Are Nutrients Really Critical?

The nutrient poor ecosystem is able to maintain its productivity under undisturbed conditions through a variety of nutrient conserving mechanisms, the most important of which are associated with the humus and root layer on top of the mineral soil.

Abstract

Nutrient poor forests are more common in the tropics than in the temperate regions, but most of the work on nutrient cycling in the tropics has been carried out on nutrient rich sites such as those in Puerto Rico and Costa Rica rather than nutrient poor sites such as those in central and eastern Amazonia. Consequently, there has been confusion as to whether nutrients are critical in tropical forests. Productivity and nutrient cycling in nutrient rich and nutrient poor forest ecosystems do not differ greatly as long as the ecosystems are undisturbed. However, when the forests are cleared for agricultural purposes, the nutrient poor systems quickly lose their productive potential, whereas the nutrient rich systems do not. The nutrient poor ecosystem is able to maintain its productivity under undisturbed conditions through a variety of nutrient conserving mechanisms, the most important of which are associated with the humus and root layer on top of the mineral soil. These mechanisms are destroyed when the nutrient poor forest is cleared for agricultural purposes.