Transcript Temperate Forest

Introduction to Ecology
Ecology
• Study of “Homes”
• Interaction of living or
Biotic and non-living or
Abiotic
Areas of Study
Ecological Levels
• Biome: are the major habitats types found on Earth
• Ecosystem: The relationships of a smaller group of organisms with each
other and their environment.
• Community The relationships between groups of different species. For
example, the desert communities consist of rabbits, coyotes, snakes, birds,
mice and such plants as saguaro cactus (Carnegia gigantea), Ocotillo,
creosote bush, etc..
• Populations: Groups of individuals of the same species in a limited
geographic area. This can be as simple as a field of flowers, which is
separated from another field by a hill or other area where none of these
flowers occur.
• Species: Groups of similar individuals who tend to mate and produce
viable, fertile offspring. We often find species described not by their
reproduction (a biological species) but rather by their form (anatomical or
form species).
Ecosystems
• Defined as all the abiotic and biotic communities that
are found in an area
• Associations largely determined by climate and soils
• These determine plant communities
• Plant communities determine animal communities
that can live in an area
• Some are defined by geological units
• Different levels of ecosystems
• Some variation depending on source
Biomes
• Biomes are the major habitats (ecosystem)
types found on Earth
• They are defined by both abiotic (non living)
and biotic (living) components
• Ecosystems include all living organisms in an
area as well as its physical environment
(including plants, animals,
fungi,microorganisms, soil, rocks, minerals,
atmosphere, water source and climate)
functioning together as a unit.
Abiotic Factors – Light Intensity
Abiotic Factors- Rainfall
Abiotic Factors
• Rainfall and
temperature over time
determine climate
• Climate determines
which plant
communities can live in
terrestrial biomes
• This in turn determines
animal communities
• Soil, wind, light and
other physical factors
are also important
Tropical Rain Forest
Tropical Forest
• latitudes 23.5 degrees N and 23.5 degrees S.
• Temperature - 20-25° C varies little
• Precipitation is evenly distributed throughout the year,
annual rainfall exceeding 2000 mm.
• Soil is nutrient-poor and acidic. Decomposition is rapid
and soils are subject to heavy leaching.
• Canopy is multilayered
allowing little light
penetration.
• Flora is highly diverse:
as many as 100 different
tree species per km
• orchids, bromeliads,
vines, ferns,
• numerous birds, bats,
small mammals, and
insects.
Tropical Rain Forest (Example)
Tropical Rain Forest
-canopy trees up to 55 m tall
-soils are generally unfertile
-largest biome, on an area
basis
-nutrients and carbon stored
in plant biomass, not soils
Tropical Savanna/Seasonal Forest
Tropical Savanna/Seasonal Forest
• Grass with scattered trees
• found in the tropics (but > 10° latitude)
Africa, India , South America, Australia
• Wet and dry season
• 50-127 cm per year
• pronounced dry season with <5 cm rainfall in some
months
• Grazing mammals, large and small predators; many birds
insects, reptiles
Tropical Savanna/Seasonal Forest
Tropical Savanna/Seasonal Forest
-scattered trees and grass
-fire & grazing by animals
also contribute to
predominance of grasses
Temperate Forest
Temperate Forest
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Temperature varies from -30° C to 30° C.
Precipitation (75-150 cm) even throughout year.
distinct winter season, frost a defining feature
summer season usually moist with precipitation > evapotranspiration
Soil is fertile, enriched with decaying litter.
Canopy allows light to penetrate, richly diversified understory
vegetation
• Flora is characterized by trees with broad leaves that are lost annually
• Fauna - squirrels, rabbits, skunks, birds, deer, mountain lion, bobcat,
timber wolf, fox, and black bear.
Temperate Forest
Temperate Forest
-relatively large tree biomass
-also called the deciduous forest,
but contains evergreen needle trees as well
Temperate Grassland/Shrubland
Temperate Grasslands
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Prairies – Large areas of N and S America and S Africa (tall grass)
Steppes of Russia (short grass; very cold winters
Mostly grass; few trees and shrubs except along waterways
Similar to tropical savanna’s but with more variation in temperature
from summer to winter
potential evapotranspiration > precipitation during summer months
Fires important to diversity
Wildflowers abundant
Grazers and their predators
Temperate Grassland/Shrubland
Temperate Grassland/Shrubland
-scattered trees and shrubs
-trees are short statured
-fire & grazing by animals
also contribute to
predominance of grasses,
but that depends on climate
Desert
Deserts
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Rainfall less than 50 cm
May be hot and dry, semiarid, cold, or chaparral (coastal)
Few mammals and few large animals
Plants adapted to lack of water – cacti and succulents
Cool at night due to reflection of sand so has wide swings in
temperature
• Coarse sandy or rocky soils
Deserts
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Hot and Dry
Semi arid- dry summers and little rainfall in winter
Cold deserts
Coastal deserts or chaparrel
Rainfall < 50cm
Plants and animals specialized for low water
Soils have abundant nutrients and little organic matter
Desert
Desert
-thorny plants
-other adaptations to conserve water
Chapparal
Chapparal
-mild winters
-seasonal rainfall, winter rain, summer drought
-maritime influence:
cold ocean currents
continental winds
Chapparal
Chapparal
-sclerophyllous plants
-adaptations to fire
Boreal Forest (Taiga)
Boreal Forest (Taiga)
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50-60 degees N; > 4 month growing season
Temperatures very low.
Precipitation primarily in the form of snow, 40-100 cm
Soil is thin, nutrient-poor, and acidic.
Flora cold-tolerant evergreen conifers with needle-like leaves
Fauna - woodpeckers, hawks, moose, bear, weasel, lynx, fox, wolf,
deer, hares, chipmunks, shrews, and bats.
Boreal Forest
Boreal Forest
-10-20 m trees
evergreen needle
and deciduous
-second largest biome,
on an area basis
-fire dominated, but on longer
timescale than grassland
-more nutrients and carbon
stored in soils than plants
Tundra
Tundra
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High latitudes or altitude
< 2 month growing season
Very cold; Precipitation 15-25cm
Very shallow soil and permafrost
Low plants and lichens
Animals adapted to cold; many hibernate
Reptiles and amphibians rare
Tundra – Mountain Tops and Arctic
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Extremely cold climate and winds
Low biotic diversity
Simple vegetation structure low shrubs, mosses, and lichens
Limitation of drainage
Short season of growth and reproduction
Energy and nutrients in the form of dead organic material
Large population oscillations
Tundra
Tundra
- no trees
- sedges, low shrubs, & mosses
- permafrost present