Ecosystems are geographic regions that hold specific environments and inhabitants.
An ecosystem is made up of plants, animals, and their surrounding physical environment.
Ecosystems are made up of biotic (living) and abiotic (non-living) parts that have important interrelationships.
Found at 60 degrees North of the equator
Extremely cold winter temperatures
Trees have thick bark to protect them from the cold
Needle leaves reduce transpiration
Shallow root systems because of shallow soil
Areas within the Arctic circle
Extremely cold temperatures
Only short grasses can survive
Very poor surface drainage
Factors that Control Ecosystems:
Climate decides the temperatures and rainfall for ecosystems and is the most important factor in the distribution and characteristics of ecosystems.
Latitude influences the amount of sunlight a region receives.
Altitude influences vegetation and temperature. As altitude gets higher, temperatures drop, soils become thinner, and there is less organic matter.
Ocean currents can affect surface temperatures and rainfall. Warm ocean currents bring warmer temperatures and cold ocean currents can sometimes bring arid conditions.
Ecosystems are extremely intricate and interdependant; a small change in an ecosystem can affect the entire system.
When an ecosystem is balanced it is in equilibrium.
When grey wolves were reintroduced into Yellowstone National Park, elk populations dropped by 50%.
This meant that grasslands could recover and more trees started to grow.
This stabilised river banks and lead to more woody debris in the rivers creating pools.
This increased the trout population.
More available food increased the grizzly bear population.