Exam 34: The Biosphere: an Introduction to Earths Diverse Environments

Why is the runoff from fertilized agricultural fields,even if free of pesticides,often harmful to the ecosystems of temperate lakes?

Rachel Carson's book,Silent Spring,deals with the

Chaparral vegetation occurs around much of the central valley of central and southern California.This biome is very similar to that found

Usually,a river _ at its source compared to farther downstream.

Which of the following could be a topic for a community- level study of a hydrothermal vent ecosystem?

The immediate results of the widespread use of pesticides and fertilizers included ,but long- term results included _.

What is the primary reason that a hot spring will kill a fish placed in it,but encourage the growth of certain bacteria?

Under the conditions known as El Niño,the mineral nutrient content of the seawater off the coast of Peru declines to very low levels.What effect will this likely have on marine life in the area?

Except near hydrothermal vents,the communities of the oceanic aphotic zone get their energy mainly from