1. 6.2 Biodiversity 6.3 Change & Response
Living Environment
Key Ideas 6.2 & 6.3

2. Living Environment Biodiversity
6.2 Explain the importance of preserving diversity of species and habitats.
6.3 Explain how the living and nonliving environments change over time and respond to disturbances.
Living Environment Biodiversity

3. Ecosystems & Biodiversity
Ecosystems tend to go through dynamic change time until a stable system (climax community) is attained.
Type of ecosystem depends upon climatic limitations of a particular geographic area.
Biodiversity is the diversity of species in an area due to evolutionary processes.
It increases the stability of an ecosystem.
It insures a large variety of genetic material.
Living Environment Biodiversity

4. Living Environment Biodiversity
Changes in Succession
Changes over time
1. Ecological Succession: changes in a community from a pioneer to climax community.
Flora (plant species) Fauna (animal species)
rock: lichens (algae & fungi)
Grass mice, rabbits
brush
tag alders
gray birch
pines
hardwoods
Plants determine the types of animals present
Living Environment Biodiversity

5. Living Environment Biodiversity
Lake Succession
Lake to Forest Succession
new lake
organisms grow and accumulate
sediment from organisms and surrounding areas accumulate in the lake bottom
becomes a mature lake community
continues to fill in
bog
trees and plants
Living Environment Biodiversity

6. Living Environment Biodiversity
Other Terms
Other terms:
Dominant species: The few important species of plants and animals that are found in a new succession area.
Climax Community: The mature, stable community at the end of succession.
Remains until there is a catastrophic event such as fire, flood, removal of topsoil, or volcanic eruption.
Primary succession: When succession occurs in an area that has no existing life.
Secondary succession: Occurs in an existing community that has been partially destroyed or balance has been upset. Ex. Forest fire.
Living Environment Biodiversity

7. Change Through Competition
Competition occurs when different species of organisms living in the same environment (habitat) utilize the same limited resources, such as food, space, water, light, oxygen, and minerals.
The more similar the requirements of the organisms involved the more intense the competition.
May be between the same or different species.
Niche is the role the species plays in its environment.
Usually one species per niche in a community.
Living Environment Biodiversity

8. Living Environment Biodiversity
Biomes
A. Biomes: large ecosystems occurring in major land areas.
similar biomes have similar plants and animals.
change with latitude
Terrestrial (dry) or aquatic (wet)
B. Types of Land Biomes:
1. Desert:
extremely dry, less than 25 cm of rain per year
cactus, shrubs, succulent plants
lizards, snakes, kangaroo rats
Living Environment Biodiversity

9. Living Environment Biodiversity
Land Biomes (cont)
2. Tropical Rainforest:
200 cm or more of rain per year
broad leafed plants, evergreens, palms
canopy over the forest from the tree
bats, snakes, lizards, monkeys, insects
3. Grasslands (steppes in Africa):
25 cm - 75 cm of rain per year
sub humid, temperatures from hot to cold
grasses, few trees
buffaloes, wolves, antelopes, prairie dogs
Living Environment Biodiversity

10. Living Environment Biodiversity
Land Biomes (cont)
4.Temperate Deciduous Forest:
75 cm or more of rain
moist cold winters, warm summers
deciduous trees, elms, maples, oaks, etc...
deer, squirrels, rabbits, turkeys
5. Taiga (coniferous forests)
50 cm or more of rain
cool and moist
conifers, evergreens, pines
bears, mountain lions, wolves, elk, moose
Living Environment Biodiversity

11. Living Environment Biodiversity
Land Biomes (cont)
6. Tundra:
20 cm of rain
cold and dry year round
permafrost
lichens, shrubs, grasses
arctic foxes, polar bears, caribou
Living Environment Biodiversity

12. Living Environment Biodiversity
World Biome Map
Living Environment Biodiversity

13. Living Environment Biodiversity
Life Zones
Living Environment Biodiversity

14. Living Environment Biodiversity
Aquatic Biomes
Aquatic biomes represent the largest ecosystems on Earth.
Over 70% of Earth’s surface covered with water.
Most of Earth’s life is found here.
Typically more stable than terrestrial biomes due to the high specific heat of water. Less temperature fluctuations.
Types of organisms found depend upon factors such as:
Amount of oxygen, carbon dioxide, light, dissolved minerals, and temperature.
Aquatic organisms are well suited for removing oxygen and controlling water balance.
Photosynthesis occurs only in about the first 100 ft.
Living Environment Biodiversity

15. Living Environment Biodiversity
Marine Biomes
Marine biomes (oceans):
Provides the most stable aquatic environment.
Absorbs and holds large quantities of solar heat and helps to stabilize the Earth’s atmosphere.
Contains a relatively constant supply of nutrient materials and dissolved salts.
Serves as a habitat for a large number of diverse organisms.
The greatest amount of food production occurs along the edges of land masses where water is less shallow.
Living Environment Biodiversity

16. Living Environment Biodiversity
Fresh Water Biome
Fresh water biomes include ponds, lakes, and rivers.
They may show great variation in:
Size
Current velocity
Concentration of dissolved gases
Suspended particles
Rate of succession- ponds and small lakes fill in quicker from dying vegetation and erosion.
Living Environment Biodiversity