Ecology Ch.1 S.4

Plant’s characteristics are important for survival
A plant’s overall shape and form help it to survive in its environment.
*e.x. - thick green stems and spines are to reduce water loss, perform photosynthesis, protect plant from herbivores.

Regions of Earth are classified into biomes.
Biomes are large regions of the world with similar plants, animals and other living things that are adapted to the climate and other conditions.

There are six major land biomes on Earth.


Taiga & Tundra Northernmost regions
They are characterized by long cold winters and short cool summers.
Temperature of the Arctic tundra: -50˚C to 18˚C
Temperature of the taiga: -40˚C to 20˚C

Tundra In the very cold places of the world, survival isn't
easy. The soil is frozen, its top surface thawing
only during summer, and no trees can grow.

Less than 25cm of precipitation each year.

The area is wet because cold temperatures keep the water from evaporating.

Permafrost is the term given to frozen soil. During the winter months, permafrost reaches the surface of the tundra. Very few animals are active in these harsh conditions.


Tundra
Plants: mosses, grasses and woody shrubs
Organisms and ecosystems: lichens, rodents, caribou, musk oxen,
Grizzly bears, white fox and snowy owls.

Taiga Temperatures are similar to those of the tundra
More precipitation (30-60cm a year.)
Evergreen trees (Coniferous) with needlelike leaves that produce food all year long.
Taiga ecosystems support deer, elk, snowshoe hares, and beavers. Predators include lynx, owls, bears, and wolves.

Desert & Grassland
Found toward the middle latitudes.
Not enough precipitation to support trees.

Desert
Some are cold and some are hot but they all have dry soil with less than 25cm of precipitation each year.

Grassland
* There is enough rain to support grasses, but not enough rain to support forest.
* Periodic wildfires & droughts
* Summer is warm and winters are cold.

Temperate Forest & Tropical Forest
Across the middle latitudes: short winter (75-150cm of precipitation each year) Near the equator: No winter. Tropical forests grow (200-450cm rain each year)

Temperate Forest A broadleaf (Deciduous)

Temperate Forest Pacific Northwest - supports coniferous

Tropical rainforest
* Located near the equator.
* Warm weather all year around.
* Trees tend to have leaves year round.
* The wettest land biome.
* The soil is poor in nutrients. High temp. cause materials to break down quickly, but there are so many plants the nutrients get used up just as quickly.



Water covers three quarter of Earth’s surface.
Freshwater biomes
Saltwater biomes

The food chains of deepwater ecosystems depend on tiny photosynthetic microorganisms called phytoplankton.


Freshwater Biomes
* Includes the still water of lakes, the running water of rivers, and estuaries where fresh and salt waters mix.
* An Estuary is the lower end of a river that feeds into the ocean.


Marine Biomes
* Saltwater biomes:
1. Coastal ocean (beach)
Organisms: crabs & clams
2. Open ocean
Receives less sunlight than costal
ocean and colder.
No plants but many types of fish
and other marine animals live.
3. Deep ocean
Much colder, the animals either
feed on each other or on material
that falls down from upper levels of the ocean