Unit Test — Unit test Answers

How has human use of salt marshes changed over time?a.Humans have come to value salt marshes and now seek to preserve and restore them.b.Humans now use drained salt marshes exclusively for agriculture.c.Humans have begun to use salt marshes for landfills.d.Humans have begun to use marsh land for housing and commercial development.

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Why are coral reefs overexploited?a.Coral is an important food resource.b.Coral and its organisms are valuable commodities in the aquarium industry.c.Coral reefs inhibit recreational activities.d.All of the above

Brackish water is common in freshwater wetlands.

Which of the following does not explain the importance of mangrove forests?a.They provide shelter to organisms on high energy coasts.b.They help prevent erosion along coasts.c.They increase surface runoff and flooding.d.They filter and process pollutants out of the environment.

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The main difference between stream pools and ponds is that stream pools _______.a.have an observable currentb.are located inlandc.have no access to rivers or streamsd.are usually larger than ponds

Where is light penetration in a river or stream likely to be lowest?a.the sourceb.the mouth c.the middle portiond.none of the above

The negative impacts of nonnative species generally outweigh the positive impacts.

Which of the following is true concerning hull fouling from commercial shipping and recreational boating?a.It constitutes less than half of all nonnative species introductions.b.The revenue brought in from these industries is relatively small.c.It is difficult to prevent since ship hulls begin, conduct, and end voyages in water.d.It is best combated by chemical treatments.

Wetlands occurring in areas with a large amount of trees are most likely _______.a.swampsb.bogsc.marshesd.none of the above

Streams have a detectable current, while rivers do not.

Legislation has been ineffective at preserving coral reefs.

Eutrophication disrupts the balance of ecosystems.

The principle difference between where salt marshes and mangrove forests grow is the salinity of the water.