Ecosystem Succession Paper

When people look at nature or the outdoors today, most people are astonished by the beauty being seen. Yet most do not know that what is seen today is not the picture of yesterday. The changes that happen in the environment are the changes that impact how communities evolve. Because of environmental changes, many societies, communities and species have formed, changed, grown and some gone extinct. According to the text, Environment, succession is the process of community development over time, which involves species in one stage being replaced by different species (pg. 67). This process can take tens, hundreds or thousands of years. Succession is an extremely important characteristic of nature and the environment. This is the process that forms the many different habitats that help nature change and evolve.

There are two kinds of succession which are dependant on the circumstances around the habitat: primary and secondary succession. According to Dictionary.com, primary succession is the development of biotic communities in a previously uninhabited and barren habitat with little or no soil (2008). Such a habitat may be formed by volcanic activity, glacial activity, or strip-mining; thus, it initially lacks soil. Examples of such habitats would include newly exposed or deposited surfaces, such as landslips, volcanic lava and debris, elevated sand banks and dunes, quarried rock faces.

A study of Glacier Bay, AL, figure 4-4, showed that following retreat of the glacier, the ground was first colonized by mosses and lichens. Lichens are often the most important element in the initial community that develops during this stage. Lichens secrete acids that help break the rock apart, which aids in the beginning process of soil formation. As soil begins to accumulate plant evolution takes place. In figure 4-4, we start with lichens, then dwarf willows, then alders, then Sitka spruce. After about 200 years, a stable spruce-hemlock forest resulted. Figure 4-4 accurately reflects the process of primary succession.

Secondary succession occurs when an existing community is completely or partially destroyed. Though, compelling as it may seem, not all is lost. Destruction or disturbance of an area of land eventually improves the area after the completion of succession. While people may find the destruction of land due to fire, volcanoes or other natural disasters, a tragedy, in actuality the destruction brings new life to the affected area. This regeneration by surviving plants and seeds is supplemented by an aggressive invasion of plant seeds from elsewhere. In secondary succession, the soil still retains much of its former character, including previous biological