In what ecosystems is the nutrient cycle the fastest?...and then what ecosystems is it the slowest?

Question

In what ecosystems is the nutrient cycle the fastest?...and then what ecosystems is it the slowest?

Answer 1

Tropical rainforests cycle nutrients superfast.  The tropics are very nutrient poor, so when a leaf falls or a creature dies the nutrients are scavenged very quickly.  It is also warm and moist year round, which is perfect for microbial decomposition.  

The tundra cycles nutrients very slowly.  It is so cold up there for most of the year that there is only a small window in the summer where microbes are active to decompose things.