Exam 30: Earths Diverse Ecosystems

Explain, in ecological terms, why cattle ranchers and conservationists have battled one another over cattle- grazing practices in the western shortgrass prairie biome of the American West. How has grazing changed the habitat?

On the basis of nutrient content, a mountain lake with little sediment or nutrients is classified as a(n) lake.

Why are mountaintops colder than valley bottoms?

In the open- water region of freshwater lakes, the zone lacks sufficient light for photosynthetic organisms.

The zone of an open- water lake receives enough light to support photosynthesis.

On the basis of nutrient content, a lake that has received large amounts of runoff from farms, feedlots, or sewage is classified as a(n) _ lake.

Coral reefs have formed as the result of

One consequence of global warming is the melting of the glaciers and the resulting rise in sea levels. What will likely be the direct effect of this increase in sea levels on coral reefs?

-What biome would you expect to find at 60° N latitude and elevations of 3,500 meters?

Earth's ozone layer is extremely important because it

Seasonal variations in temperature are due to the tilt of Earth on its axis.

Permafrost is associated with which of these biomes?

Thick, water- storing leaves and stems and shallow, spreading roots are adaptations to

are flat lands surrounding rivers that are covered with nutrient- rich sediments when water overflows the banks.

The destruction of the layer increases the amount of damaging UV light that reaches Earth's surface.

Estuaries have very low bioproductivity and diversity.

Why is the human- caused damage to coral reefs of particular concern?

Oligotrophic lakes

Why do plants dominate and define communities on land?

The greatest diversity of plants and animals is found in