Primary succession occurs on bare, lifeless substrate, such as rocks, or in open water, where organisms gradually move into an area and change its nature. It is a very slow process and takes a few hundreds of years. In the pioneer stages of primary succession, bare rock becomes covered with lichens and mosses. The a field grows, which causes shrubs and small trees to take over that area. The next stages are made up of seeds of trees being carried by wind and growing into pine, birch. and aspen trees. The trees dominate the fields. The final stages of primary succession have the other types of trees thrive and grow, and a coniferous forest is then "complete".

Secondary succession occurs in areas where an existing community has been disturbed but the soil still remains. Secondary succession typically follow fires, recession of glaciers, and changes in stream channels. In the result of a fire (because lighting fires are natural) it releases nutrients in the leaf litter of coniferous needles which enriches the soil. The fires releases seeds by causing cones to burst open. Although you would expect it to take a while for the plants to grow in the burned area, it grows and sprouts fast. Plants go through the approximately the same stages as primary succession's later stages. Plant secondary succession is also evident following the melting of permafrost and resulting distribution of the ground surface.


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