Question

The biodiversity in a coral reef ecosystem can be changed by both natural and human activities. What is a natural factor that would most likely decrease the ecosystem biodiversity

Answer 1

The source of sunlight is the main source of energy and if there will be more sea weed trapping sunlight then there will be a competition between seaweed and coral reef. So, the natural reason for the decreased biodiversity is an overgrowth of the seaweed population which prevents the light from reaching the reef.