The Amazon rainforest is considered to be one of the most complex and species-rich ecosystems on Earth.
The remarks above show that some of the complexity and diversity results from the locational diversity.
This biodiversity has developed on mostly nutrient-poor and acidic soil, upon which humus layers developed as a refuge for decomposers.
Very high ecosystem productivity is achieved by the formation of almost self-contained, internal nutrient cycles, internal a large number of organisms.
This depends on the maintenance of the geochemical cycles. Disruption to these cycles can have catastrophic consequences that can only be balanced out over extremely long periods.
For a long time it was assumed that this diversity was the result of a process of adaptation that had been going on for millions of years.
However this, idea has been revised in recent years, because the climate was not constant and there were repeated local or regional disasters.
For example, during the Ice Age the climate was colder in the Tropics as well; occasional fire and floods led to temporary, locally limited destruction of the forests.
However, these phenomena did not destroy the flora and fauna, as the Ice Ages did in Europe or North America; through the destruction they led to an increase in biodiversity.
The entire system is by no means uniform. Differences in the soil precipitation, floods and geochemical inputs, linked to differing dry periods, caused evolution that varied greatly from place to place.
All of this means that the Amazon basin is a colorful mosaic of the most varied ecotopes with living communities in a varying stage of succession, but which has hardly been researched to date in terms of its multifaceted strictures and functions.
Biological Diversity in the Amazon basin
