Directions: Read the following articles below about primary and secondary succession, then answer the questions that appear at the bottom of this page.  This information will form the background of what we will discuss in class about succession.  First, however, look at the definitions below:

Definitions

1. Ecological Succession: The progressive replacement of one dominant type of species or community by another in an ecosystem until a stable climax community is established. (http://www.biology-online.org/dictionary/Ecological_succession)
2. Primary Succession: An ecological succession that occurs following an opening of uninhabited, barren habitat or that occurs on an environment that is devoid of vegetation and usually lacking topsoil.  (An example of primary succession is the initial development of plant or animal communities in an area where no soil initially exists (such as caused by a lava flow following volcanic eruption or severe landslide that covered the land). The primary succession is important in pioneering the area to create conditions favorable for the growth of other forms of plants and animals.) (http://www.biology-online.org/dictionary/Primary_succession)
3. Secondary Succession: The ecological succession that occurs on a preexisting soil after the primary succession has been disrupted or destroyed due to a disturbance that reduced the population of the initial inhabitants.  (An example of secondary succession is the development of new inhabitants to replace the previous community of plants and animals that has been disrupted or disturbed by an event (e.g. forest fire, flood, harvesting, epidemic disease, pest attack, etc.).) (http://www.biology-online.org/dictionary/Secondary_succession)

Articles

1. General Succession Info: http://www.physicalgeography.net/fundamentals/9i.html
2. Sand Dune Primary Succession (England): http://www.countrysideinfo.co.uk/successn/primary2.htm
3. Secondary Succession (England): http://www.countrysideinfo.co.uk/successn/second.htm

Questions

1. Distinguish between primary and secondary succession.  Include two specific examples for each in your answer.
2. Outline the changes in species diversity and ecosystem productivity during primary succession.
3. Explain the effects of living organisms on the abiotic environment, with reference to the changes during primary succession.
4. Using an example, discuss the importance of human impact on secondary succession.