1. The Biosphere: An Introduction to Earth’s Diverse Environments
Chapter 34
The Biosphere: An Introduction to Earth’s Diverse Environments

2. A Mysterious Giant of the Deep
There are about 1,000 known species of squid
But until recently, no one had reported on this “mystery squid”

3. Deep-sea submersibles
Are allowing scientists to study uncharted depths of the ocean
Figure A

4. At depths of up to 2,500 meters
Scientists are observing new environments and a great variety of organisms
Figure B
Figure C

5. Ecology
Is the scientific study of the interactions of organisms with their environments

6. 34.1 Ecologists study how organisms interact with their environment at several levels
At the organismal level
Ecologists may examine how one kind of organism meets the challenges of its environment
Figure 34.1

7. At the population level
Ecologists might study factors that limit population size
At the community level
An ecologist might focus on interspecies interactions

8. Ecosystem interactions involve
Living (biotic) communities and nonliving (abiotic) physical and chemical factors

9. 34.2 The biosphere is the total of all of Earth’s ecosystems
Is the global ecosystem
Figure 34.2A

10. Patchiness of the environment Characterizes the biosphere
Figure 34.2B

11. 34.3 Environmental problems reveal the limits of the biosphere
CONNECTION
34.3 Environmental problems reveal the limits of the biosphere
Human activities, including the widespread use of chemicals
Affect all parts of the biosphere

12. Rachel Carson, a famous ecologist
Was one of the first people to perceive the global dangers of pesticide use
Figure 34.3

13. 34.4 Physical and chemical factors influence life in the biosphere
Abiotic factors determining the biosphere’s structure and dynamics include
Solar energy, water, temperature, wind, and disturbances
Figure 34.4

14. 34.5 Organisms are adapted to abiotic and biotic factors by natural selection
Unique adaptations
Allow the survival of organisms in particular habitats
Figure 34.5

15. Biotic factors, such as predation and competition
Can lead to the evolution of adaptations by natural selection

16. 34.6 Regional climate influences the distribution of biological communities
Most climatic variations
Are due to the uneven heating of Earth’s surface as it orbits the sun
Low angle of incoming sunlight
Sunlight strikes most directly
Low angle of incoming sunlight
Atmosphere
60ºS South Pole
Tropic of Capricorn 30ºS
0º (equator)
30ºN Tropic of Cancer
North Pole 60ºN
Figure 34.6A

17. The tilt of the Earth’s axis
Causes the changes of the seasons in the northern and southern hemispheres
March equinox (equator faces sun directly)
June solstice (Northern Hemisphere tilts toward sun)
Constant tilt of 23.5º
December solstice (Northern Hemisphere tilts away from sun)
September equinox
Figure 34.6B

18. Ascending moist air releases moisture
The uneven heating of the Earth
Also sets up patterns of precipitation and prevailing winds
Descending dry air absorbs moisture
Trade winds
Ascending moist air releases moisture
Doldrums
Temperate zone
Tropics
30º
23.5º 0º
60ºN
30ºN
30ºS
Figure 34.6C, D

19. Influence coastal climate
Ocean currents
Influence coastal climate
Fresno 104º
Paso Robles 93º
Bakersfield 106º
Death Valley 119º
Pacific Ocean
Santa Barbara 75º
Los Angeles (Airport) 74º
San Diego 75º
40 miles
San Bernardino 101º
Riverside 91º
Palm Springs 104º
Burbank 86º
Santa Ana 84º
Key
70s (ºF)
80s
90s
100s
110s
Figure 34.6E

20. Landforms such as mountains Affect rainfall
Pacific Ocean
Coast Range
Wind direction
Sierra Nevada
East
Figure 34.6F

21. 34.7 Oceans occupy most of Earth’s surface
AQUATIC BIOMES
34.7 Oceans occupy most of Earth’s surface
Several characteristics shape ocean communities
Light, distance from shore, and the availability of nutrients

22. The intertidal zone, an oceanic zone
Is the area of shore where the ocean meets the land
Figure 34.7A

23. Oceanic zones also include The pelagic and benthic zones
Intertidal zone
Photic zone
200 m
Continental shelf
2,500–6,000 m
Benthic zone (seafloor)
Pelagic zone
Aphotic zone
Figure 34.7B

24. Are found in warm waters above continental shelves
Coral reefs
Are found in warm waters above continental shelves
Figure 34.7C

25. Are productive areas where rivers flow into the ocean
Estuaries
Are productive areas where rivers flow into the ocean
Figure 34.7D

26. 34.8 Freshwater biomes include lakes, ponds, rivers, streams, and wetlands
Factors that shape lake and pond communities include
Light, temperature, and the availability of nutrients and dissolved oxygen

27. Abiotic factors change from the source of a river to its mouth
And communities vary accordingly
Figure 34.8A

28. Wetlands include
Marshes and swamps
Figure 34.8B

29. 34.9 Terrestrial biomes reflect regional variations in climate
Temperature and rainfall
Mainly determine the terrestrial biomes

30. Major terrestrial biomes
30ºN
Tropic of Cancer
Equator
Tropic of Capricorn
30ºS
Tropical forest
Savanna
Desert
Chaparral
Temperate grassland
Temperate broadleaf forest
Coniferous forest
Tundra
High mountains
Polar ice
Figure 34.9

31. 34.10 Tropical forests cluster near the equator
Tropical rain forests
Are the most diverse ecosystem
Figure 34.10

32. 34.11 Savannas are grasslands with scattered trees
Are dry and warm
Figure 34.11

33. 34.12 Deserts are defined by their dryness
Are the driest biomes
Figure 34.12

34. 34.13 Spiny shrubs dominate the chaparral
Is a shrubland with cool, rainy winters and dry, hot summers
Figure 34.13

35. 34.14 Temperate grasslands include the North American prairie
Are found where winters are cold
Figure 34.14

36. 34.15 Broadleaf trees dominate temperate forests
Temperate broadleaf forests grow throughout midlatitude regions
Where there is sufficient moisture to support the growth of large trees
Figure 34.15

37. 34.16 Coniferous forests are often dominated by a few species of trees
The northern coniferous forest, or taiga
Is found where there are short summers, and long, snowy winters
Figure 34.16

38. 34.17 Long, bitter-cold winters characterize the tundra
Arctic tundra
Is a treeless biome characterized by extreme cold, wind, and permafrost
Figure 34.17

39. Alpine tundra
Occurs above the treeline on high mountains

40. 34.18 Ecologist Ariel Lugo studies tropical forests in Puerto Rico
TALKING ABOUT SCIENCE
34.18 Ecologist Ariel Lugo studies tropical forests in Puerto Rico
The Luquillo Experimental Forest
Allows ecologists to study the effects of disruption on tropical forests
Figure 34.18A, B