Primary
Succession begins with bare rock exposed by geologic activity .
First to appear on the bare rock are lichens and algae.These secrete acids which begin to extract nutrients from the rock and which form tiny cracks which are widened by freezing and thawing. As the cracks widen, they trap enough organic material and moisture for mosses to take hold. Larger cracks have enough soil to support grasses and small shrubs.
First to appear on the bare rock are lichens and algae.These secrete acids which begin to extract nutrients from the rock and which form tiny cracks which are widened by freezing and thawing. As the cracks widen, they trap enough organic material and moisture for mosses to take hold. Larger cracks have enough soil to support grasses and small shrubs.
Secondary
Succession after a disturbance that destroys the community without destroying the soil.
A common succession in the savanna of Central Kalahari are the high frequency of seasonal fires that burn down many of the trees and lots of the grass. Some species on the plains have developed certain adaptations to make them fireproof. Seeds from outside the affected area blow in and establish themselves in the soil. Over time, larger and larger plants grow and this later supports a variety of animals.
A common succession in the savanna of Central Kalahari are the high frequency of seasonal fires that burn down many of the trees and lots of the grass. Some species on the plains have developed certain adaptations to make them fireproof. Seeds from outside the affected area blow in and establish themselves in the soil. Over time, larger and larger plants grow and this later supports a variety of animals.