1. Ecology
the scientific study of the interactions between organisms and the environment

2. Organisms and the Environment
Abiotic factors
nonliving components
Biotic factors
living components
collectively called the biota
Biosphere
global ecosystem
sum of all the planet’s ecosystems

3. LE 50-7
New areas
occupied
Year
1996
1989
1974

4. Biotic Factors
Biotic factors that affect the distribution of organisms may include:
Interactions with other species
Predation
Competition

5. August 1982 February 1983 August 1983 February 1984
LE 50-8
100
Sea
urchin
Both limpets
and urchins
removed 80
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

6. Abiotic Factors Abiotic factors affecting distribution of organisms:
Temperature
Water
Sunlight
Intensity
Photoperiod
Wind
Rocks and soil
Mineral composition pH

7. Climate Four major abiotic components of climate:
Temperature
Water
Sunlight
Wind
Climate = prevailing weather in an area

8. Low angle of incoming sunlight
LE 50-10a
North Pole
60°N
Low angle of incoming sunlight
30°N
Tropic of
Cancer
Sunlight directly overhead at equinoxes
0° (equator)
Tropic of
Capricorn
30°S
Low angle of incoming sunlight
60°S
South Pole
Atmosphere

9. Seasonal variations of light and temperature increase steadily toward the poles

10. LE 50-10b
March equinox: Equator faces sun directly; neither pole tilts toward sun; all regions on Earth experience 12 hours of daylight and 12 hours of darkness.
60°N
30°N
June solstice: Northern Hemisphere tilts toward sun; summer begins in Northern Hemisphere; winter begins in Southern Hemisphere.
0° (equator)
30°S
December solstice: Northern Hemisphere tilts away from sun; winter begins in Northern Hemisphere; summer begins in Southern Hemisphere.
Constant tilt
of 23.5°
September equinox: Equator faces sun directly; neither pole tilts toward sun; all regions on Earth experience 12 hours of daylight and 12 hours of darkness.

11. Global air circulation and wind patterns play major roles in determining climate patterns

12. LE 50-10c 60°N 30°N 0° (equator) 30°S 60°S Descending dry air absorbs
moisture
Descending
dry air
absorbs
moisture
0° (equator)
Ascending
moist air
releases
moisture
30°S
60°S
30°
23.5° 0°
23.5°
30°
Arid
zone
Tropics
Arid
zone

13. Arctic Circle 60°N Westerlies 30°N Northeast trades Doldrums 0°
LE 50-10d
Arctic
Circle
60°N
Westerlies
30°N
Northeast trades
Doldrums 0°
(equator)
Southeast trades
30°S
Westerlies
60°S
Antarctic
Circle

14. Wind direction East Pacific Ocean Sierra Nevada Coast Range
LE 50-12
Wind
direction
East
Pacific
Ocean
Sierra
Nevada
Coast
Range

15. Long-Term Climate Change
One way to predict future global climate change is to study previous changes

16. Current range Predicted range Overlap 4.5°C warming over
LE 50-14
Current
range
Predicted
range
Overlap
4.5°C warming over
next century
6.5°C warming over
next century

17. Aquatic biomes account for the largest part of the biosphere in terms of area
They can contain fresh water or salt water
Oceans cover about 75% of Earth’s surface and have an enormous impact on the biosphere

18. LE 50-15 30°N Tropic of Cancer Equator Continental shelf Tropic of
Capricorn
30°S
Key
Lakes
Rivers
Estuaries
Abyssal zone
(below oceanic
pelagic zone)
Coral
reefs
Oceanic
pelagic zone
Intertidal
zone

19. Many aquatic biomes are stratified into zones or layers defined by light penetration, temperature, and depth

20. Littoral zone Limnetic zone Photic zone Pelagic zone Benthic zone
LE 50-16a
Littoral
zone
Limnetic
zone
Photic
zone
Pelagic
zone
Benthic
zone
Aphotic
zone
Zonation in a lake

21. (deepest regions of ocean floor)
LE 50-16b
Intertidal zone
Neritic zone
Oceanic zone
Photic zone
200 m
Continental
shelf
Pelagic
zone
Benthic
zone
Aphotic
zone
2,500–6,000 m
Abyssal zone
(deepest regions of ocean floor)
Marine zonation

22. Major aquatic biomes: Lakes Wetlands Streams and rivers Estuaries
Intertidal zones
Oceanic pelagic biome
Coral reefs
Marine benthic zone

23. Lakes

24. Wetlands

26. Rivers & Streams

29. Intertidal Zones

30. Oceanic

31. Coral Reefs

32. Marine Benthic Zone

33. Annual mean temperature (°C)
LE 50-18
Desert
Temperate grassland
Tropical forest 30
Temperate
broadleaf
forest 15
Annual mean temperature (°C)
Coniferous
forest
Arctic and
alpine
tundra
–15
100
200
300
400
Annual mean precipitation (cm)

34. LE 50-19
30°N
Tropic of
Cancer
Equator
Tropic of
Capricorn
30°S
Chaparral
Key
Tundra
Temperate grassland
High mountains
Tropical forest
Temperate broadleaf forest
Polar ice
Savanna
Coniferous forest
Desert

35. Terrestrial Biomes
often named for major physical or climatic factors and for vegetation

36. Major terrestrial biomes:
Tropical forest
Desert
Savanna
Chaparral
Temperate grassland
Coniferous forest
Temperate broadleaf forest
Tundra

37. Tropical Forest

38. Desert

39. Savannah

40. Chaparral

41. Temperate Grassland

42. Coniferous Forest (Boreal Forest or Taiga)

43. Temperate Broadleaf (Deciduous) Forest

44. Tundra