1. CHAPTER 34 The Biosphere: An Introduction to Earth's Diverse Environments
Modules 34.1 – 34.6

2. A Mysterious Giant of the Deep
Ecology is the scientific study of the interactions of organisms with their environment
The ocean is Earth’s largest and least explored ecosystem
Recent explorations of the deep sea have brought previously unknown species to light, such as this “mystery squid”

3. Deep-sea submersibles like Alvin allow the exploration of the deep sea
It can accommodate a pilot and two other people
It is equipped with instruments to view and sample the ocean at depths of up to 2,500m

4. Scientists have found seafloor life whose ultimate energy source is not sunlight, but energy that comes from the interior of the planet
This energy is emitted from hydrothermal vents near the edges of Earth’s crustal plates

5. Many animals thrive in the extreme environment around hydrothermal vents
Tube worms were unknown to science until hydrothermal vents were explored
They live on energy extracted from chemicals by bacteria

6. 34.1 Ecologists study how organisms interact with their environment at several levels
Ecologists study environmental interactions at the organism, population, community, and ecosystem levels
These clams that live near an ocean vent constitute a population
Figure 34.1

7. Hierarchy Review
Organism level – individual organisms interact with aspects of immediate surroundings
Population level – focus on functioning among all the members of an interbreeding group and its environment
Communities – focus on all the organisms of all species and their interactions within one particular area

8. Ecosystem level – adds nonliving factors (abiotic components) to the the relationship among living factors (biotic components)

9. Organisms are affected by their environment
Ecosystem interactions involve living (biotic) communities and nonliving (abiotic) components
Abiotic components include energy, nutrients, gases, and water
Organisms are affected by their environment
But their presence and activities often change the environment they inhabit

10. 34.2 The biosphere is the total of all of Earth's ecosystems
The global ecosystem is called the biosphere
It is the sum of all the Earth's ecosystems
The biosphere is the most complex level in ecology
Figure 34.2A

11. Biosphere includes atmosphere to an altitude of a few kilometers, the land to a soil depth of a few meters, all lakes and streams, and the ocean to a depth of several kilometers
Biosphere is isolated by space

12. The biosphere is self-contained
except for energy obtained from the sun and heat lost to space
Patchiness characterizes the biosphere
Patchiness occurs in the distribution of deserts, grasslands, forests, and lakes
At each level patchiness is is a result of habitats (places where organisms live)
Each habitat has a unique community of species
Figure 34.2B

13. 34.3 Connection: Environmental problems reveal the limits of the biosphere
Human activities affect all parts of the biosphere
Effects of technology: chemicals for agriculture (fertilizer/pesticides) major environmental impacts
Rachel Carson – DDT  bald eagles
** Carson data from Rosalie Edge (plug for Rosenberg’s aunt’s book – “Hawk of Mercy”
Environmental degradation, famine, species endangerment, and extinction all tied to human activities, including land misuse, expanding human population, incursions into natural habitats, and poisoning of soil and water by toxic wastes

14. Rachel Carson was one of the first to perceive the global dangers of pesticide abuse
Carson documented her concerns in the 1962 book Silent Spring
This book played a key role in the awakening of environmental awareness
Figure 34.3

15. Biosphere Influences

16. 34.4 Physical and chemical factors influence life in the biosphere
The most important abiotic factors that determine the biosphere's structure and dynamics include
Solar energy – powers terrestrial and shallow water ecosystems
Exception are the chemoautotrophs
Availability of light is critical factor affecting distribution of photosynthetic organisms and their dependents
Water – essential to all life
In aquatic environments, water balance must be maintained in diverse ionic concentrations.
In terrestrial environments, water must be conserved.

17. Temperature – affects rate of metabolism and the functioning of enzymes
Metabolism typically between 0’ C and 50’ C
Soil structure, pH, nutrient content are important factors for plants.
Oxygen not limiting for terrestrial, but typically for aquatic
Fire and other catastrophes are infrequent and unpredictable in most ecosystems
Fire’s importance for the grasslands
Wind – brings nutrients to some organisms, but causes damage, increases evaporation and lowers effective temperatures.

18. Disturbances such as fires, hurricanes, and volcanic eruptions are also abiotic factors
Figure 34.4

19. Natural selection adapts organisms to abiotic and biotic factors
34.5 Organisms are adapted to abiotic and biotic factors by natural selection
The presence and success of a species in a particular place depends upon its ability to adapt
Natural selection adapts organisms to abiotic and biotic factors
Biotic factors include predation and competition
Figure 34.5

20. Evolution and Ecology Species exist due to evolution or dispersion
Unique adaptations to environment allow survival
Pronghorn designed for conditions on the plains of North America. Move to forests, will not survive
Abiotic conditions
Daily/seasonal temperature fluctuations
Aridity
Wind
Pronghorn with coat of hollow hairs and gets water from diet
Biotic conditions
Diet – coarse grasses/woody shrubs
Predators – Wolves, coyotes, cougars
Adaptive teeth for chewing and ruminant digestive system and speed/endurance, camouflaged, good eye sight, live in herds

21. 34.6 Regional climate influences the distribution of biological communities
Climate often determines the distribution of communities
Earth's global climate patterns are largely determined by the input of solar energy and the planet's movement in space

22. Most climatic variations are due to the uneven heating of Earth's surface
This is a result of the variation in solar radiation at different latitudes
North Pole
60º N
Low angle of incoming sunlight
30º N
Tropic of Cancer
Sunlight directly overhead
0º (equator)
Tropic of Capricorn
30º S
Low angle of incoming sunlight
60º S
Atmosphere
South Pole
Figure 34.6A

23. The seasons of the year result from the permanent tilt of the plant on its axis as it orbits the sun
MARCH EQUINOX (equator faces sun directly)
JUNE SOLSTICE (Northern Hemisphere tilts toward sun)
DECEMBER SOLSTICE (Northern Hemisphere tilts away from sun)
SEPTEMBER EQUINOX
Figure 34.6B

24. The tropics experience the greatest annual input and least seasonal variation in solar radiation
The direct intense solar radiation near the equator has an impact on the global patterns of rainfall and winds

25. moist air releases moisture
Ascending
moist air releases moisture
Descending dry air absorbs moisture
Descending dry air absorbs moisture
Trade winds
Trade winds
Doldrums 0º
23.5º
23.5º
30º
30º
TROPICS
TEMPERATE ZONE
TEMPERATE ZONE
Figure 34.6C

26. Warm, moist air at the equator rises
As the air rises, it cools and releases much of its water content
This results in the abundant precipitation typical of most tropical regions
After losing their moisture over equatorial zones, high altitude air masses spread away from the equator

27. They cool and descend again at latitudes of about 30° north and south
This explains the locations of the world's great deserts
As the dry air descends, some of it spreads back toward the equator
This creates the cooling trade winds that dominate the tropics

28. Temperate zones are located between the tropics and the Arctic Circle in the north and the Antarctic Circle in the south
They have seasonal variations in climate
The temperatures are more moderate than in the tropic or polar regions

29. Prevailing winds result from the combined effects of the rising and falling of air masses and Earth's rotation
In the tropics, Earth's rapidly moving surface deflects vertically circulating air, making the winds blow from east to west
In temperate zones, the slower-moving surface produces the westerlies, winds that blow from west to east
Figure 34.6D

30. Ocean currents have a profound effect on regional climates by warming or cooling coastal areas
They are created by winds, planet rotation, unequal heating of surface waters, and the locations and shapes of continents

31. Local high temperatures for August 6, 2000, in Southern California
Fresno 100º
40 miles
Death Valley 119º
Bakersfield 100º
Pacific Ocean
Burbank 90º
Santa Barbara 73º
San Bernardino 100º
Key
Riverside 96º
Los Angeles (Airport) 75º
70s (ºF)
Santa Ana 84º
Palm Springs 106º
80s
90s
100s
110s
San Diego 72º
Figure 34.6E

32. Landforms, such as mountains, can affect local climate
East
Wind direction
Pacific Ocean
Cascade Range
Coast Range
Figure 34.6F