Question

If a forest ecosystem is removed through clear-cutting, many species of organisms that lived in that ecosystem disappear. Their loss is due to what

Answer 1

Part of the ecosystem that they lived in was destroyed. Organisms like fungus and decomposers feed off dead leaves and bark, without decomposers, mice and other small carnivores won't have food, therefore whatever eats mice, has nothing to eat and a whole cycle is broken.

Answer 2

http://www.ecokids.ca/pub/eco_info/topics/forests/threats.cfm
^ this is a fun website that'll help you.