Primary Succession

Primary Succession Primary Succession is an ecological succession process that occurs in an environment with no prior inhabitants. Primary succession is the changes in species composition over time in a previously uninhabited environment. When primary succession begins no soil exist; rock surfaces like volcanic lava and glacier scraped rock surfaces are the platform on which primary succession begins. In figure 4.4 of the text Primary succession is happening on glacier moraine after the glacier has deposited rocks, gravel and sand. Pioneer Community is the initial community that develops during the primary succession process. Lichens are the most important element of the pioneer community.
The lichens helps breakdown of the rocks by secreting acid on the rocks to break them apart and thus starts the soil formation process. After sometime, mosses and drought-resistant ferns replaces the lichen community, followed by tough grass and herbs. Plant life like dwarf trees and shrubs will later appear. The ecological process of primary
Secondary succession is the changes in species composition which occurs after a disturbance that destroys the existing vegetation and soil. Secondary succession can be caused by fire or the abandonment of non-cultivated farm lands. Biologists report that secondary succession takes more than 100 years to occur at a particular site once the soil is disturbed. In figure 4.5, secondary succession is happening due to the abandonment of the farm land. Abandon farm lands not cultivated for a time usually develop weeds such as crabgrass which is considered a dominant species, and further on other weeds like horseweeds begin to grow. Horseweeds are not a dominant species and therefore, the roots decay after the plant has gone through its life cycle giving way to other plant life such as brooms-edge and other