Question

Explain how nutrients become available in the soil by answering the following questions: Why would the soils in tropical rain forests generally be depleted of their nutrients more rapidly compared to the nutrients in temperate forest soils? Why is the organic horizon (the O Horizon) absent from desert soils?

Answer 1

A rainforest depending upon the heat and humidity to move on the microbial organisms, as well as fungi to decompose faunal/ floral remains. This decomposition releases nutrients and minerals back into the soils. This is a part of the nitrogen cycle. Due to climate/ weather change, these microbes and fungi aren't thriving as well as they once did. Rainforest soil is also very acidic and this generally inhibiting the release of viable nutrients.
Increased rain actually causes leaching of nutrients from soil.

as there is no plant are present in the desert,this is very rare,only in the oasis.as there is very less plant present in desert no organic material are growing in the soil.so the organic horizon absent from the desert soils.