Why do equatorial regions have fertile soils?
Answers
It’s not clear to me that equatorial regions have more fertile soils than other (e.g. temperate) regions of the planet. To be clear, the Earth’s Equator bisects many different terrestrial biomes from the mountains of the Andes, to the grasslands of the Serengeti, to the rainforests of the Amazon, Congo, and Indonesia. Some of soils of these regions are fertile, others are not.
Weathering and having washed most of the nutrients out of the soil.
Tropical soils are formed in areas with high annual temperature and rainfall and the soil lacks in fertility.
In dry season, more of the nutrients cannot stay.
Comparatively, less organic matter is present in the vegetation of the rainforest than that of temperate forests, because the warm humid conditions makes them decay faster and recycling of nutrients back into living forest.