Introduction to Ecology

1
Introduction to Ecology

• Chapter 50

2
Ecology

• Study of interactions between organisms and the
  environment
• Interactions ?determine the abundance and
  distribution of organisms
• Since prehistoric times humans are interested in
  this dist. abund.? WHY???

3
Ecology

• Changing? was a descriptive science, now is
  becoming more of an experimental science
• Provides a scientific context for evaluation of
  environmental issues
• Is very closely related to evolutionary biology

4
Environment

• Affects the distribution of organisms
• Is made up of
• Abiotic? no living components
• Biotic? living components

5
Abiotic Factors

• Light
• Water
• Temperature
• Soil
• O2/CO2
• Periodic disturbances in all these leads to
  species diversity

6
Biotic Factors

• Individual organisms
• Populations
• Communities
• Ecosystems
• Biosphere? global ecosystem
• All living organisms of the earth ?portion that
  can sustain life

7
Distribution of Organisms

• Distinct global and regional patterns in the
  distribution of organisms
• Biogeography is the study of past and present
  distributions of individual species
• Ecologists? what limits the geographical
  distribution of any species

8
Factors that Affect Distribution

• Species dispersal
• Behavior and Habitat Selection
• Biotic factors
• Abiotic

9
(No Transcript)
10
Species dispersal

• Transplanted species
• Successful ?potential range of the species is
  larger than the actual range.
• Unsuccessful, ?distribution is limited by other
  species or abiotic factors

11
Problems with Introduced Species

• Transplanted species? explode
• Ex African honeybee Zebramussel

12
Behavior and Habitat Selection

• organisms select particular habitats
• Insects ? oviposition, breeding areas
• Chemical signaling between plants and pollinators
• Evolution does not produce the perfect organism?
  populations do not evolve overnight, even natural
  selection may not be

13
Biotic Factors

• Predators limit distribution of prey species

14
Abiotic Factors

• Temperature
• Water
• Sunlight
• Wind
• Rocks and soil

15
Temperature and Water

• Climate is the prevailing weather conditions in
  an area
• major components? Temperature, water, light, and
  wind
• Climate determines the makeup of Biomes

16
Climate and Biomes
17
Temperature and Water

• Global Climate Patterns ?Sunlight Planets
  movement

18
Temperature and Water contd

• Local and seasonal effects on climate
• Microclimate
• Long-term climate change
• Effect of mountains on rainfall

19
Biomes

• A distinct ecological community of plants and
  animals living together in a particular climate
• Biomes often run into each other
• Major types
• Aquatic
• Terrestrial

20
Aquatic Biomes

• Vertical stratification of aquatic biomes
• The photic zone
• The aphotic zone
• Thermocline
• The benthic zone

21
Freshwater biomes

• The littoral zone is shallow and close to shore.
• The limnetic zone is the open surface water.
• The profundal zone consists of the deep, aphotic
  regions.

22
Lakes

• Oligotrophic

23
Lakes

• Eutrophic

24
Streams and Rivers
25
Wetlands
26
Estuaries
27
Zones in Marine Communities
28
Coral Reefs
29
Terrestrial Biomes

• Tropical Rain forest
• Savanna
• Desert
• Chaparal
• Temperate grasslands
• Temperate deciduous forest
• Coniferous forest
• Tundra

30
The Spatial Scale of Distributions

• Different factors may determine the distribution
  of a species on different scales
• Most species have small geographic ranges