349 MBCB  Challenge Questions  Chapter 5  Shallow-Water Subtidal Benthic Associations

Research and answer the following questions in complete sentences and paragraphs.

1.                  What factors tend to allow for the high productivity of the shallow-water regions?  What influences does this have on animal production?

2.                  What is the Petersen grab sampler?  Why was it invented?  What does it do?

3.                  What is a keystone species?  What is a keystone predator?  Name some keystone species and or predators in terrestrial ecosystems and in aquatic ecosystems.

4.                  Compare the productivity of kelps and seagrasses.

5.                  What is a sea pen?  To what phylum does it belong?  How does it feed?  What is unusual about large sea pen communities?  Discuss.

6.                  Of what importance are sediment stabilizers to the benthos?  Discuss

7.                  Of what importance are sediment destabilizers to the benthos?  Discuss.

8.                  Summarize and discuss how sea urchins are important to the kelp beds.

9.                  How might seagrass provide a refuge for bivalves from predatory gastropods?  Discuss.

10.              Explain how seagrass beds are nursery grounds for numerous species.