Answers to Questions 1 – 5 Pg 67
1.
Q: Describe the differences between primary and secondary succession.
A: Primary succession involves the establishment of an ecosystem where there was no ecosystem previously. Secondary succession is the replacement of one community of biotic elements by another in an area where there had been an ecosystem previously.
2.
Q: Explain to an adult what might happen to a vacant lot in your community if it were left alone for the next 25 years.
A: A vacant lot will change and include more plant and animal life as it is left alone. Grasses and weeds will be replaced by larger plants and possibly shrubs or small trees, and as the plant community changes, more and different animals will also begin to inhabit the area.
3.
Q: List four different events that could change a climax community. For each one, suggest what the area might look like two years after the event.
A: Some examples are,
- Forest Fire: the area will have small shrubs and some small trees starting to grow.
- Avalanche: the area will have some small plants, shrubs, and possibly the beginnings of some new trees.
- Development: the area would have little or no evidence of the climax community and would be developed for
human use.
- Tornado: the area will have some smaller plants and shrubs, and possibly the beginnings of some new trees.
4.
Q: How does your knowledge of ecosystems help you understand the process of succession?
A: An ecosystem is a place where biotic and abiotic elements have a variety of interactions and where the elements are always changing. Succession is a process in which ecosystems are changing as a result of interactions between biotic and abiotic elements.
5.
Q: Explain how the following events could be important in the formation of a new community of living things.
a) Fish-eating birds land on rocky island; b) a coconut is washed up on a beach; c) an especially high tide washes seaweed onto a sandy beach.
A: a) By consuming the fish on the rocks, the wastes birds eliminate will begin to add some nutrients to the island. Over time this may lead to some soil that could have enough nutrients for small plants to start growing.
b) The coconut could sprout roots that anchor the coconut to the beach as well as anchor some of the beach itself (stop it from eroding). The coconut could start to grow into a palm tree.
c) The seaweed could provide habitat for small animals. It could eventually break down, adding nutrients to the soil that would support some plant growth on the beach.