Ecology Exam Study Notes

Community Dynamics

Community Differences:
- Species Richness: Number of species.
- Relative Abundance: Number of individuals per species.
- Food Web:
- Nature of Interactions
- Physical Structure: Growth forms of plants.
Keystone Species:
- Has a disproportionate impact on the community relative to its abundance.
- Example: Mountain lions impacting deer and grasses.
Relative Species Richness and Abundance:
- Tropical Rainforest: High species richness and abundance.
- Desert: Low species richness and abundance.
Types of Feeders (Trophic Levels):
- Producers (Autotrophs): Organisms doing photosynthesis (plants/algae).
- CO2 + H2O \rightarrow Sugar + O_2
- Consumers (Heterotrophs): Eating organisms.
  - Primary Consumers: Herbivores.
  - Secondary Consumers: Carnivores.
  - Tertiary Consumers: Carnivores.
Trophic Levels (Example):
- 1°: Producers (plants)
- 2°: Primary Consumers (giraffe, insects)
- 3°: Secondary Consumers (bigger big cats, bigger birds, bigger coyote)

Terrestrial Biomes

Key Factors: Temperature and Precipitation.
Examples:
- Desert: High temperature, low precipitation.
- Tropical Rainforest: High temperature, high precipitation.
- Temperate Rainforest
- Tundra.
- Grasslands
Photosynthesis and Transpiration:
- Photosynthesis: CO2 + H2O \rightarrow Sugar + O_2
- Transpiration: Water evaporation through leaves.
Local Biomes (California Example):
- Coastal Sage Scrub
- Chaparral
- Riparian
- Oak Woodland

Hydrologic Cycle

Linked to aquatic biomes.
Key Processes:
- Evaporation: Liquid to gas.
- Condensation: Gas to liquid.
- Precipitation: Rain and snow.
- Percolation: Water soaks into the soil.
- Runoff: Water moving down a slope.
- Transpiration: Water evaporation through leaves.
- Groundwater: Water in the ground.

Aquatic Biomes

Lake: Inland depression full of water.
- Formation:
  - Glacial erosion
  - Natural dams
  - Animal dams
  - Volcanic craters
- Zonation:
  - Limnetic Zone: Open water to the depth of maximum light penetration.
  - Littoral Zone: Shallow water with many rooted plants.
  - Benthic Zone: Floor; decomposition occurs here.
  - Profundal Zone: From limnetic zone to the bottom.
- Nutrients: Based on surrounding landscape.
  - Eutrophication: Nutrient-rich aquatic systems.
  - Oligotrophication: Conditions poor in nutrients, little input from surrounding areas.
Flowing Water (Rivers/Runoff):
- Fast Moving:
  - Smooth rocks
  - High sediment flow (sawdust)
  - Animals are hydrodynamic (compressed to reduce drag); young animals tether.
- Slow Moving:
  - High vegetation
  - Animals are designed to move through vegetation without getting stuck.
Estuary:
- Area where saltwater and freshwater converge.
- High biodiversity; natal grounds for fish and birds.
- Sensitive to pollution, fertilizers, and changes in salinity.
- Anadromous: (e.g., salmon) Born in freshwater, later moves to saltwater.
- Catadromous: Born in saltwater, later moves to freshwater.
Ocean:
- Zonation:
  - Pelagic Zone: Open water.
    - Epipelagic Zone: Surface to 200m; huge changes in light, temperature, and salinity.
    - Mesopelagic Zone: 200m-1000m; very low light and low oxygen.
    - Bathypelagic Zone: 1000m-4000m; totally dark, cold, high pressure.
    - Abyssopelagic Zone: 4000m to sea floor.
    - Hadalpelagic Zone: Deep sea trenches.
Coral Reef:
- Fringing Reef: Grows towards the sea from rocky shores.
- Barrier Reef: Grows parallel to the shore; has a lagoon (calm water).
- Atoll: Circular reef around a sunken volcano.
Intertidal Zone (Tide Pools):
- Supratidal Zone: Transition from land to sea; mostly exposed.
- Littoral Zone: Areas covered and uncovered by tides.
- Subtidal Zone: Uncovered at the lowest of low tides.

Other Biomes

Grasslands
- Photosynthesis: CO2 + H2O \rightarrow Sugar + O_2
- Transpiration: Water evaporation through leaves.
Tundra
Local
- Salt marsh areas dictated by tides and salinity, creating diverse plant communities
- Freshwater wetlands:
  - Marsh: dominated by reeds, cattails, and grasses.
  - Swamp: flooded forest
  - Riparian: occasionally or seasonally flooded-lines rivers
  - Mine: wetlands that retain water by the accumulation of decayed trees
  - Bog: mire that gets its water by rain

Biology 259 - Study Guide for Exam #3 Key Terms

Species richness
Relative abundance
Biodiversity
Predation
Pioneer species
Climax species
Fragmentation
Corridors
Biome
Temperature
Precipitation
Competition
Symbiosis
Keystone species
Generalist
Specialist
Producer
Autotroph
Photosynthesis
Consumer
Heterotroph
Herbivore
Carnivore
Omnivore
Desert
Tundra
Grassland
Forest
Permafrost
Coastal sage scrub
Chaparral
Riparian
Estuary
Eutrophication
Oligotrophication
Rivers
Oceans
Pelagic zone
Epipelagic zone
Mesopelagic zone
Bathypelagic zone
Abyssopelagic zone
Coral Reef
Fringing reef
Barrier reef
Atoll
Intertidal zone
Supratidal zone
Subtidal zone
Ecotone
Trophic level
Food chain
Food web
Succession
Lakes
Zonation
Littoral zone
Primary succession
Secondary succession
Marsh
Swamp
Limnetic zone
Mire
Profundal zone
Benthic zone
Plankton
Bog

Study Guide Topics

Community Dynamics
- Food chains and food webs - trophic levels and how do each work?
- Succession primary vs. secondary, pioneer vs. climax species
Ecosystems
- Factors that affect global terrestrial and aquatic biomes
- Global terrestrial biomes - descriptions for each and adaptations for organisms living there
  - Deserts, tundra, forests, grasslands
- Local biomes - chaparral, coastal sage scrub, riparian
- Aquatic biomes
  - Lakes and ponds - formation and zonation
  - Flowing water - animal and plant/algae adaptations
  - Estuaries - description, problems organisms face here
  - Oceans - zonation, coral reefs, kelp forests
  - Intertidal zones - zones, problems organisms face here
- Freshwater wetlands - types and descriptions
  *Videos: Ocean Deep, Deserts, and Seasonal Forests