Major Ecosystems of the Biosphere Flashcards
The thirteen large terrestrial and aquatic ecosystem distributed throughout Earth’s surfaces are according to what?
Climate
What is a ecosystem?
A very large naturally occurring community of living species occupying a major habitat associated with nonliving aspects like moisture content and temperature
Temperatures may vary greatly between deserts, stark changes in temperature in night and day, very little rainfall (less than 25 cm annually), and the winds lack moisture are characteristics of what ecosystem?
Deserts
The world’s deserts are growing due to what?
Deserification
What is desertification?
When arid climates dry-out adjacent moisture climates and desert plants and habitat spread
In biblical times, Sahara was less than what percent of current size?
10%
What are the four deserts in the United States?
Great Basin Desert, Mojave Desert, Chihuahuan Desert, and Sonoran Desert
The continent of Africa is how many times larger than the United States?
Four times
What is the main cause of desertification?
Overgrazing and felling of trees and brushwood for fuel
How much of Africa faces becoming a desert?
One-third
Dry shrubland and insufficient rain prevents succulent plant growth of taller trees are characteristics of what ecosystem?
Chaparral
Where are chaparrals found?
South California, Wyoming, Utah, and western United States
The characteristics of cold winters, plants in dormancy, fairly low rainfall, well adapted to a changing climate, and prevents spreading of trees with less than 5% of tree coverage are to what ecosystem?
Grasslands
What decides if a grass prairie is short, tall, or mixed?
The amount of rainfall, where more rainfall = taller grass
What are examples of short grass prairies?
Kansas and Nebraska
What are examples of tall grass prairies?
Missouri
What are examples of mixed grass prairies?
South Dakota and Saskatchwan
In the United States, grasslands were mainly found where?
The midwest
What is a savannah?
Grasslands with trees sparsely dotting the landscape.
The rainfalls of Africa cause what to occur occasionally and what thrives?
Trees occur occasionally but grass thrives
Native people of Missouri maintained savannas by burning what forests every few years?
Oak-hickory
Fire-intolerant species were killed so what could dominate?
Grasses
Are there any savannas found in the US?
No, no savannas are found in the US
Long, cold, snowy winters with warm and humid summers where evergreen species dominate. Low water availability makes these species able to compete in northern subarctic regions, tiny leaves lose very little water, photosynthesize even during coldest time of year, absorb water through snow (not much rain), and 50% of trees on Earth are characteristics of what ecosystem?
Coniferous forests
What are three examples of evergreen species?
Pines, firs, and spruces
Leaf loss in autumn prevents excessive water loss during cold winter months when water is frozen, well-defined seasons, and moderate climate with relatively high rainfall are characteristics of what ecosystem?
Temperate deciduous forests