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
Temperate deciduous forests are the dominant forests of where in the United States?
Southern Missouri and most of the eastern United States
What does deciduous mean?
A land plant that sheds its leaves annually
How much of temperate rain forests are left?
1% left as the rest converted to chaparral or managed tree farms
Where are temperate rain forests found?
Only in northwest North America such as North California, Oregon, Washington, and British Columbia, Canada
Temperate rain forests were destroyed extensively by what and what most of the forests outside of which two spots are gone?
Destroyed extensively by logging companies & shipped overseas which has led to most of the forests outside of parks and reserves being gone.
12 hours of sunlight, weather that is always warm, a lot of rainfall, and generally nutrient pour soil are characteristics of what ecosystem?
Tropical rain forests
The most rapidly disappearing ecosystem on Earth is?
The tropical rain forest
Tropical rain forests are home to what percentage of species on Earth?
80%
How many species are undiscovered and how many go extinct in tropical rain forests?
Millions are undiscovered and hundreds go extinct every day
Why are soils generally nutrient poor in tropical rain forests?
Recycling by fungi is so efficient and nothing gathers long enough to become a soil nutrient
How many inches of rain does Costa Rica get and what ecosystem is it?
Tropical rain forest and 400 inches
Tropical rain forests are also known as what?
The world’s largest pharmacy
What are the five layers of a tropical rain forest?
Emergent layer, canopy, understory, shrub layer, and forest floor
Where are tropical rain forests found?
28 degrees north and south of the equator
Permafrost prevents what in tundras?
Tree species from surviving
Harsh, long, cold winters, short summers, low rainfall, cold and dark most of the year, and incapable of supporting any plant life with roots over 6 inches are characteristics of what ecosystem?
Tundras
In the tundra, below 6 inches, even during summer it is permanently what and what do you hit at 3 inches?
Permanently frozen below 6 inches and ice at 3 inches
Where are tundras found?
Frozen soils of the far north and south
What plants grow in tundras?
Low-growing shrubs, lichen, mosses, and grasses
What are the nine terrestrial ecosystems?
Tundras, temperate rain forests, tropical rain forests, savannas, coniferous forests, grasslands, deserts, temperate deciduous forests, and chaparral.
What are the four aquatic ecosystems?
Lakes, estuaries, rivers, and oceans and seas
What are lakes?
Bodies of freshwater characterized by how much mineral nutrient is allowed to wash inside of them as it affects their lifespan
More nutrients in lakes leads to more rapidly tiny what that proliferate which ultimately leads to what and what?
Algea, dying, and filling the lake
Low nutrient lakes are also called what and are blank lived?
Oligotrophic and long
High nutrient lakes are also called what and are blank lived?
Eutrophic and short lived
What are examples of things washed into short living lakes?
Fertilizers washed in from farms, golf courses, yards, and etc.
Jacomo and Longview must be periodically what?
Dredged
Eutrophication means?
Process in which a body of water receives a large input of nutrients in a relatively short period of time.
What is an estuary?
A partially enclosed body of coastal marine water where periodic additions of freshwaters from streams comes in. (Part of an ocean where fresh water and salt water meet and mix)
Most oceanic animals breed where?
In estuaries
The health of the oceans’ wildlife depends on the health of the what?
Estuaries
What are examples of estuaries?
Mangrove swamps, mudflats, coastal bays, fjords, rocky shores, marshes, wetlands, and some lagoons
What are rivers?
Natural watercourse, usually freshwater, flowing towards an ocean, lake, sea, or another river.
The ocean is a major body of what water and covers what percentage of the Earth’s surface?
Saline and approximately 71%
The ocean is often divided into what?
Several principle oceans and smaller seas
What is a sea?
It is usually located where ocean and land meet and typically seas are partially enclosed by land
About what % of the oceans are over 9,800 feet deep?
50%
The average salinity of the ocean is what?
Approximately 3.5%
Nearly all seawater has a salinity range of what to what.
3-3.8%
Approximately how many marine animals are known and that number could actually be how many times higher?
230,000 and up to x10 higher
What type of water is a mixture of fresh and salt water?
Brackish water
