1. Chapter 52- An Introduction of Ecology and the Biosphere

2. Ecology
Ecology is the scientific study of the interactions between organisms and the environment
These interactions determine distribution of organisms and their abundance

3. Organism
Population
Community
Ecosystem
Landscape
Global

4. Ecology and Distribution
We can use Ecology to find out WHY an organism is dispersed a certain way.
Distribution of red kangaroos in Australia.
What biotic/abiotic factors are affecting the kangaroo population?

5. What can you infer from this picture?
What kind of environments are found in different regions in Australia?

6. Another example?

7. Concept 52.2: Interactions between organisms and the environment limit the distribution of species
Biogeography- ?
Ecologists study two factors that limit distribution
Biotic
living factors (examples??)
Abiotic
nonliving factors (examples??)

8. Possible Factors Affecting Distribution
Dispersal
Behavior/Habitat Selection
Biotic Factors-
Abiotic Factors-
Climate-

9. Dispersal and Distribution
Dispersal -movement of individuals away from centers of high population density / area of origin

10. Natural Range
Current
1970
1960
1966
1965
Natural Range expansions show how dispersal affects distribution (usually move b/c of people)
1961
1958
1943
1951
1937
1956
1970

11. Species Transplants
organisms that are intentionally or accidentally relocated from their original distribution
can disrupt the communities or ecosystems to which they have been introduced
Why??

12. Behavior and Habitat Selection
Some organisms do not occupy all of their potential range because of habitat selection behavior
Examples? Think of any animal

13. Biotic Factors Interactions with other species Predation Competition
AKA

14. August 1982 February 1983 August 1983 February 1984
Fig. 52-8
RESULTS
100
Both limpets and urchins
removed 80
Sea urchin
Only urchins
removed 60
Seaweed cover (%)
Limpet 40
Only limpets removed 20
Control (both urchins
and limpets present)
August
1982
February
1983
August
1983
February
1984

15. Abiotic Factors
Abiotic factors affecting distribution of organisms include:
Temperature
Water
Sunlight
Wind
Rocks and soil

16. Special on Temperature
Temperature affects biological processes:
Cells may freeze and rupture below 0°C, while most proteins denature above 45°C
Mammals and birds expend energy to regulate their internal temperature

17. Water Desert organisms exhibit adaptations for water conservation
Salt concentration affects water balance of organisms through osmosis; few land organisms adapted for high salt

18. Salinity
Salt concentration affects water balance of organisms through osmosis; few land organisms adapted for high salt

19. Sunlight Light intensity and quality affect
_____________________
In aquatic environments most photosynthesis occurs
____________________
In deserts, high light levels increase temperature
(we know!)

20. Rocks and Soil
Soil physical structure, pH and Mineral composition affect distribution

21. Fig. 52-9

22. Climate Four major abiotic components:
temperature
water
sunlight
wind
AKA long-term prevailing weather conditions

23. Global Climate Patterns
Determined mostly by solar energy and Earth’s position relative to the sun
Ex.

24. Low angle of incoming sunlight
Fig b
90ºN (North Pole)
60ºN
Low angle of incoming sunlight
30ºN
23.5ºN (Tropic of
Cancer)
Sun directly overhead at equinoxes
0º (equator)
23.5ºS (Tropic of
Capricorn)
30ºS
Low angle of incoming sunlight
60ºS
90ºS (South Pole)
Atmosphere

25. WHY do we have Seasons??
Please be smarter than some recent Harvard grads!

26. 60ºN 30ºN March equinox 0º (equator) June solstice 30ºS
Fig c
60ºN
30ºN
March equinox
0º (equator)
June solstice
30ºS
December solstice
Constant tilt
of 23.5º
September equinox

27. Air Circulation
Air circulation, Wind Patterns are predictable b/c why?
Warm wet air flows from the tropics toward the poles

28. Arid zone Tropics Arid zone
Fig e
60ºN
Descending
dry air
absorbs
moisture
Descending
dry air
absorbs
moisture
30ºN 0º
(equator)
Ascending
moist air
releases
moisture
30ºS
60ºS
30º
23.5º 0º
23.5º
30º
Arid
zone
Tropics
Arid
zone

29. Bodies of water and Mountains
Water affects Climate
The Gulf Stream carries warm water from to
Oceans and their currents and large lakes moderate the climate of nearby terrestrial environments- example??

30. Warm air over land rises.
Fig
Air cools at
high elevation. 2
Cooler
air sinks
over water. 3
Warm air
over land rises. 1
Cool air over water
moves inland, replacing
rising warm air over land. 4

31. Fig
Labrador
current
Gulf
stream
Equator
water
Warm
Cold water

32. More water daily patterns
During the day, air rises over warm land and draws a cool breeze from the water across the land
As the land cools at night,

33. Mtns
Affect:
Rising air releases moisture on the windward side of a peak and creates a “rain shadow” as it absorbs moisture on the leeward side

34. Wind direction Mountain range
Fig
Leeward side
of mountain
Wind
direction
Mountain
range
Ocean

35. Flowchart of Factors Fig. 52-6
Why is species X absent
from an area?
Yes
Area inaccessible
or insufficient time
Yes
Does dispersal
limit its
distribution?
Habitat selection
Yes
Predation, parasitism,
competition, disease
Does behavior
limit its
distribution?
Chemical
factors No
Do biotic factors
(other species)
limit its
distribution?
Water
Oxygen
Salinity pH
Soil nutrients, etc. No
Do abiotic factors
limit its
distribution? No
Temperature
Light
Soil structure
Fire
Moisture, etc.
Physical
factors
Figure 52.6 Flowchart of factors limiting geographic distribution

36. Long-term climate change?
Comments, questions?

37. Global climate change will profoundly affect the biosphere
One way to predict future global climate change is to study previous changes
As glaciers began retreating 16,000 years ago, tree distribution patterns changed
As climate changes, species that have difficulty dispersing may have smaller ranges or could become extinct

38. Current range Predicted range Overlap (a) 4.5ºC warming over
Fig
Current
range
Predicted
range
Overlap
(a) 4.5ºC warming over
next century
(b) 6.5ºC warming over
next century

39. Tropic of Cancer Equator Tropic of Capricorn
Fig
Lakes
Coral reefs
Rivers
Oceanic
pelagic and
benthic zones
Estuaries
30ºN
Intertidal zones
Tropic of
Cancer
Equator
Tropic of
Capricorn
30ºS

40. Stratification of Aquatic Biomes
Stratifiwhonow?
Divided based on light penetration, temperature and depth

41. 52.4: The structure and distribution of terrestrial biomes are controlled by climate and disturbance
Climate is very important in determining why terrestrial biomes are found in certain areas
Biome patterns can be modified by disturbance such as a storm, fire, or human activity

42. Climograph Desert Temperate grassland Tropical forest 30 Temperate
Fig
Climograph
Desert
Temperate grassland
Tropical forest 30
Temperate
broadleaf
forest 15
Annual mean temperature (ºC)
Northern
coniferous
forest
Arctic and
alpine
tundra
–15
100
200
300
400
Annual mean precipitation (cm)

43. Ecotone
The transition from one type of habitat (or ecosystem) to another
Usually there is no clear cut and dried boundary btwn habs/ecos

44. Major Terrestrial Biomes
Tropical forest
Savanna
Desert
Chaparral
Temperate
grassland
Temperate
broadleaf forest
Northern
coniferous forest
Tundra
High mountains
Polar ice

45. Terr. Biome facts to KNOW
Warmer Biomes usually have greater diversity (think rainforest)
Species that thrive in harsh biomes have specific adaptations
Desert species adapt to low water environments
High Salt, low light, low temperature all have adaptations
Layers are important:
Forests have a canopy, low tree, understory, ground/herbaceous plants, root layers.
Tundra has Permafrost then unfrozen underneath

46. Let’s Talk about Tropical forest Savanna Desert Chaparral
Temperate Grassland
Temperate Broadleaf Forest
Northern Coniferous forest
Tundra
High Mountain
Polar Ice

47. What conclusion would you make from the following data?

48. 100 Mean height (cm) 50 3,000 Altitude (m) 2,000 Sierra Nevada
Fig. 52-UN2
100
Mean height (cm) 50
3,000
Altitude (m)
2,000
Sierra Nevada
1,000
Great Basin
Plateau
Seed collection sites