Five Biomes of Alaska
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Tundra
Boreal Forest
Temperate Rain Forest
Wetlands
Ocean
Vocabulary
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Biome: A large community of plants and animals that occupies a distinct region.
Terrestrial biomes, typically defined by their climate and dominant vegetation, include grassland,
tundra, desert, tropical rainforest, and deciduous and coniferous forests. There are two basic
aquatic biomes, freshwater and marine, which are sometimes further broken down into categories
such as lakes and rivers or pelagic, benthic, and intertidal zones.
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Biotic: Consisting of living organisms. An ecosystem is made up of a biotic community
(all of the naturally occurring organisms within the system) together with the physical
environment.
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Abiotic: Not associated with or derived from living organisms. Abiotic factors in an
environment include such items as sunlight, temperature, wind patterns, and precipitation.
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Ecosystem: A community of organisms together with their physical environment,
viewed as a system of interacting and interdependent relationships and including such processes
as the flow of energy through trophic levels and the cycling of chemical elements and
compounds through living and nonliving components of the system.
Tundra
Characteristics of tundra include: Characteristics of
tundra include:
1. Extremely cold climate
2. Low biotic diversity
3. Simple vegetation structure
4. Limitation of drainage
5. Short season of growth and reproduction
6. Energy and nutrients in the form of dead
organic material
7. Large population oscillations
Boreal
Forest
Characteristics of the Boreal Forest
1. Temperatures are very low.
2. Precipitation is primarily in the form of snow, 40-100 cm
annually.
3. Soil is thin, nutrient-poor, and acidic.
4. Canopy permits low light penetration, and as a result,
understory is limited.
5. Flora consist mostly of cold-tolerant evergreen conifers
with needle-like leaves, such as pine, fir, and spruce.
6. Fauna include woodpeckers, hawks, moose, bear,
weasel, lynx, fox, wolf, deer, hares, chipmunks, shrews,
and bats.
Temperate Rainforest
Characteristics of the Temperate Rainforest
1. Temperature varies from -30° C to 30° C.
2. Precipitation (75-150 cm) is distributed evenly throughout the
year.
3. Soil is fertile, enriched with decaying litter.
4. Canopy is moderately dense and allows light to penetrate,
resulting in well-developed and richly diversified understory
vegetation and stratification of animals.
5. Flora is characterized by 3-4 tree species per square kilometer.
Trees are distinguished by broad leaves that are lost annually and
include such species as oak, hickory, beech, hemlock, maple,
basswood, cottonwood, elm, willow, and spring-flowering herbs.
6. Fauna is represented by squirrels, rabbits, skunks, birds, deer,
mountain lion, bobcat, timber wolf, fox, and black bear.
Wetlands
Characteristics of Wetlands:
1. Wetlands are areas of standing water that support aquatic plants.
Marshes, swamps, and bogs are all considered wetlands.
2. Plant species adapted to the very moist and humid conditions are
called hydrophytes. These include pond lilies, cattails, sedges, tamarack,
and black spruce. Marsh flora also include such species as cypress and
gum.
3. Wetlands have the highest species diversity of all ecosystems. Many
species of amphibians, reptiles, birds (such as ducks and waders), and
furbearers can be found in the wetlands.
4. Wetlands are not considered freshwater ecosystems as there are some,
such as salt marshes, that have high salt concentrations — these
support different species of animals, such as shrimp, shellfish, and
various grasses.
Ocean
Characteristics of the Ocean:
1.
2.
3.
The largest of all the ecosystems, oceans are very
large bodies of water that dominate the Earth's
surface.
The ocean regions are separated into separate zones:
intertidal, pelagic, abyssal, and benthic. All four
zones have a great diversity of species.
Some say that the ocean contains the richest diversity
of species even though it contains fewer species than
there are on land.
Alaska’s Biomes!
A rich diverse
home to a
plethora of
organisms.