For example, if a tree falls in a forest, the light gap formed creates new niches for new species to invade. You also needed to explain that at high frequencies of disturbance, species simply can't get established before they are wiped out by another disturbance, hence low species diversity. And, at low frequency of disturbance, species diversity is low because there are few available niches. Communities, under low disturbance, tend to reach a successional stage where a few species dominate and use up most of the resources. So there just aren't resources and niches available for other species to invade, hence species diversity is low.
Warm air rises, moves away from the equator, cools and sinks back towards earth.
As the warm air rises, it expands and loses heat, so it can hold less water, so it rains where the air is rising. By the time the air is starting to sink, it is very dry. Discuss the relationship of the Iron Hypothesis to global Carbon cycles. The algae are limited by the availability of iron. For any two different biomes, explain how these biomes differ and explain what is driving these differences.