Ecosystems
A group of organisms interacting
with each other and their
environment through a flow of
energy and the cycling of matter.
• An ecosystem is a natural system
consisting of all plants, animals and
microorganisms (biotic factors) in an area
functioning together with all the non-living
physical (abiotic) factors of the
environment.
Biotic Factors
• All living things in an ecosystem.
• Examples=
• Animals, plants, insects, fish
Abiotic
• All non-living physical factors of the
environment
• Examples
• Water, Air, Dirt, Rocks
Biomes
• Large geographic areas that have similar
climates and ecosystems.
• Seven common types of biomes
• 1. Desert, 2. Grassland, 3. Tropical
Rainforest, 4. Temperate rainforest, 5.
deciduous forest, 6. Taiga, 7. Tundra.
Desert
• Driest biome
• Less than an inch of rain a year
• Does not support large plant and animal
populations
Grassland
• Grasslands are characterized as lands
dominated by grasses rather than large
shrubs or trees.
Tropical Rainforest
• Tropical forests are characterized by the
greatest diversity of species. They occur
near the equator. One of the major
characteristics of tropical forests is their
distinct seasonality: winter is absent, and
only two seasons are present (rainy and
dry). The length of daylight is 12 hours and
varies little.
Deciduous Forest
• forests occur in eastern North America,
northeastern Asia, and western and
central Europe. Well-defined seasons with
a distinct winter characterize this forest
biome.
Taiga
• Boreal forests, or taiga, represent the
largest terrestial biome in the world
Tundra
• Tundra is the coldest of all the biomes.
Tundra comes from the Finnish word
tunturi, meaning treeless plain. It is noted
for its frost-molded landscapes, extremely
low temperatures, little precipitation, poor
nutrients, and short growing seasons.
Aquatic Ecosystems
• Freshwater is defined as having a low salt
concentration — usually less than 1%.
Plants and animals in freshwater regions
are adjusted to the low salt content and
would not be able to survive in areas of
high salt concentration (i.e., ocean). There
are different types of freshwater regions:
• Ponds and lakes
• Streams and rivers
Marine
• Marine regions cover about three-fourths of the
Earth's surface and include oceans, coral reefs,
and estuaries. Marine algae supply much of the
world's oxygen supply and take in a huge
amount of atmospheric carbon dioxide. The
evaporation of the seawater provides rainwater
for the land.
• Oceans
• Coral reefs
• Estuaries
Succession
• Ecological succession, a fundamental
concept in ecology, refers to more-or-less
predictable and orderly changes in the
composition or structure of an ecological
community. Succession may be initiated
either by formation of new, unoccupied
habitat (e.g., a lava flow or a severe
landslide) or by some form of disturbance
(e.g. fire, severe windthrow, logging) of an
existing community.
Ecological Succession