1. Bright blue marble floating in space Chapter 52
Intro to Ecology
We are, for all intents and purposes, on a spaceship. We get inputs of energy from the sun and some donation of material from asteroids, but most material needs to be recycled w/ in our planet.

2. What is ecology? Ecology These interactions
Is the scientific study of the interactions between organisms and the environment
These interactions
Determine both the distribution of organisms and their abundance
Where organisms are found and how many of them there are.
Study of interactions between organisms - interdependence of nature and energy transfer. Other themes we can think of?

3. What is ecology? Ecology Ecological time
Both observational/descriptive and experimental
Observing what’s there and seeing how it changes.
Rigorous - mathematical modeling of populations and ecosystems.
Ecological time
Minute-to-minute interactions.
Compare to evolutionary time.

4. Heirarchy Organism/Individual
Population: group of individuals of same species living in a particular geographic area
Community: group of populations of different species in an area
Ecosystem: community of organisms + physical (abiotic) factors
Landscape: mosaic of connected ecosystems
Biosphere: global ecosystem

6. Environmental factors
Abiotic factors
non-living chemical & physical factors
Temperature
Light
Wind
Water, including salinity
Soil and rocks
Dissolved oxygen!
Biotic factors
living components
Abiotic factors - also includes pH, soil quality (though this is biotic and abiotic), seasonal changes, etc.

7. Environmental Factors
Affect the distribution and abundance of organisms
Kangaroos/km2
> 20
10–20
5–10
1–5
0.1–1
< 0.1
Limits of distribution
Climate in northern Australia
is hot and wet, with seasonal
drought.
Red kangaroos
occur in most
semiarid and arid
regions of the
interior, where
precipitation is
relatively low and
variable from
year to year.
Southeastern Australia
has a wet, cool climate.
Southern Australia has
cool, moist winters and
warm, dry summers.
Tasmania

8. prefer a hot dry climate. don’t like saltwater.
The figure below (Figure 52.5 in the textbook) shows the distribution of red kangaroos in Australia. From this figure, you can predict that kangaroos:
eat plants.
prefer a hot dry climate.
don’t like saltwater.
prefer to live in areas where people don’t live.
are more abundant in some years than in other years.
Kangaroos/km2
> 20
10–20
5–10
1–5
0.1–1
< 0.1
Limits of distribution
Climate in northern Australia
is hot and wet, with seasonal
drought.
Red kangaroos
occur in most
semiarid and arid
regions of the
interior, where
precipitation is
relatively low and
variable from
year to year.
Southeastern Australia
has a wet, cool climate.
Southern Australia has
cool, moist winters and
warm, dry summers.
Tasmania

9. Dispersal
Dispersal - the movement of individuals away from their area of origin or from centers of high population density.
Natural range expansion
Early humans “out of Africa”
Different from migration.
Species transplants
Potential vs. actual ranges
Where organisms could be versus where they are.
Invasive/introduced species.

10. Earth’s biomes
Terrestrial biomes - we’ll be looking at marine and aquatic biomes later.

11. Environmental factors
Climate - Long-term prevailing weather in a particular area.
Macroclimate - Patterns on a global, regional and local level.
Microclimate - Patterns on a smaller scale.
Ex: A community living under a log.
Abiotic factors - also includes pH, soil quality (though this is biotic and abiotic), seasonal changes, etc.
Lichen
Rotting Logs
Tide Pools

12. Why do we have weather?
Latitudinal variation in sunlight intensity.

13. Seasonal variation in sunlight intensity.
Why do we have weather?
Seasonal variation in sunlight intensity.

14. Why do we have weather?
Global air circulation and precipitation patterns.

15. Why do we have weather? Global wind patterns.
Currents and other bodies of water.

16. Why do we have weather?
Mountains and elevation.

17. Biomes: major types of ecosystems that occupy very broad geographic regions

18. Climate and elevation determine biomes
Figure 34.7C
Figure 34.12

19. Climograph: plot of temperature & precipitation in a particular region

20. Marine/Aquatic Biomes
coral reef
benthos
intertidal

21. Marine/Aquatic Biomes
Tropic of Cancer
Equator
30S
Continental shelf
Lakes
Coral reefs
Rivers
Oceanic pelagic zone
Estuaries
Intertidal zone
Abyssal zone (below oceanic pelagic zone)
Key
Tropic of
Capricorn
coral reef
benthos
intertidal

22. Aquatic/Marine Biomes
Account for the largest part of the biosphere in terms of area
Can contain fresh (aquatic), brackish, or salt (marine) water
Oceans
Cover about 75% of Earth’s surface
Have an enormous impact on the biosphere

23. Zonation
Are stratified into zones or layers defined by light penetration, temperature, and depth
Thermoclines - Narrow vertical zone of abrupt temperature change.
Marine zonation. Like lakes, the marine environment is generally classified on the basis of light penetration (photic and aphotic zones), distance from shore and water depth (intertidal, neritic, and oceanic zones), and whether it is open water (pelagic zone) or bottom (benthic and abyssal zones).
Zonation in a lake. Based on light penetration, distance from short and water depth, and open water or bottom.
(a)
Littoral zone
Limnetic zone
Photic zone
Benthic zone
Aphotic zone
Pelagic zone
Intertidal zone
Neritic zone
Oceanic zone
200 m
Continental shelf
Pelagic
zone
2,500–6,000 m
Abyssal zone (deepest regions of ocean floor)
(b)

24. Nutrient turnover
Lakes and other marine/aquatic biomes experience turnover. (*Remember from chemistry….water is most 4 degrees C and least dense at 1 degree)
In spring, as the sun melts the ice, the surface water warms to 4°C
and sinks below the cooler layers immediately below, eliminating the
thermal stratification. Spring winds mix the water to great depth,
bringing oxygen (O2) to the bottom waters (see graphs) and
nutrients to the surface. 2
In winter, the coldest water in the lake (0°C) lies just
below the surface ice; water is progressively warmer at
deeper levels of the lake, typically 4–5°C at the bottom. 1
In autumn, as surface water cools rapidly, it sinks below the
underlying layers, remixing the water until the surface begins
to freeze and the winter temperature profile is reestablished. 4
In summer, the lake regains a distinctive thermal profile, with warm surface water separated from cold bottom water by a narrow
vertical zone of rapid temperature change, called a thermocline. 3
Winter
Spring
High
Medium
Low
O2 concentration
O2 (mg/L)
Lake depth (m) 8 12 16 24
Autumn
Summer
4C 4 2 0 6 8
18
20
22 5
Thermocline

25. Wetlands Inundated with water at least periodically
Okefenokee National Wetland Reserve in Georgia
Inundated with water at least periodically
Plants adapted to water-saturated soil
Highly productive
Important filters and breeding grounds
Birds, carnivores, crustaceans, plants, reptiles.

26. Lakes Oligotrophic - nutrient poor, oxygen rich
Eutrophic - nutrient rich, oxygen poor
Periodic oxygen depletion; large amount of decomposition
Biota - fish, invertebrates depending on O2 levels, phyto- and zooplankton.
Human impact- Fertilized land runoff and dumping wastes-algae blooms
An oligotrophic lake in Grand Teton, Wyoming
A eutrophic lake in Okavango delta, Botswana
LAKES

27. Streams and Rivers Current with lots of aeration
Figure 50.17
A headwater stream in the Great Smoky Mountains
The Mississippi River far form its headwaters
Current with lots of aeration
Great diversity of fish and invertebrates
Aquatic plants and phytoplankton, fish, invertebrates, etc.
Ex. Potomac; Mississippi
Human impact- pollution

28. Estuaries Transition between rivers and sea
Variable salinity depending on temperature, depth, and tides.
Abundant worms, oysters, crabs, fish, etc.
Many marine invertebrates breed here
Crucial feeding areas for waterfowl and some marine mammals
Human impact: disruption by pollution from upstream
Figure 50.17
An estuary in a low coastal plain of Georgia
ESTUARIES
Chesapeake bay oyster reefs and restoration efforts.

29. Rocky intertidal zone on the Oregon coast
Intertidal Zones
Figure 50.17
INTERTIDAL ZONES
Rocky intertidal zone on the Oregon coast
Marine shores periodically submerged and exposed by tides.
Physical environment varies vertically (may be rocky or sandy), so species range varies vertically.
Oxygen and nutrients renewed tidally.
Sea grass, algae, worms, crustaceans, crabs, etc.
Human impact: oil spills

30. Open ocean off the island of Hawaii
Oceanic Pelagic Biome
Figure 50.17
Open ocean off the island of Hawaii
OCEANIC PELAGIC BIOME
Open ocean, particularly deep water.
Driven by currents - lots of light and oxygen. Large photic zone.
Experience nutrient turn over - depends on temperature.
70 percent of world’s surface
Phytoplankton and photosynthetic bacteria - makes our oxygen!
Zooplankton, fish, cephalopods, marine mammals, etc.
Human impact- overfishing

31. A coral reef in the Red Sea
Coral Reefs
Formed from coral calcium carbonate “skeletons”
Photic zone – ‘shallow’ species need light for photosynthesis; sensitive to change in temperature
Unicellular algae, coral animals, fish and invertebrate diversity. Rivals tropical rainforest for diversity
Human impact- collecting coral skeletons; overfishing
Figure 50.17
A coral reef in the Red Sea
CORAL REEFS

32. A deep-sea hydrothermal vent community
Marine Benthic Zone
Ocean floor
Deep benthic = abyssal zone; deep sea vents with chemoautotrophs.
Shallow benthic - oxygen from algae and seaweed.
Chemo- or photoautotrophs; worms, arthropods, echinoderms, etc.
Human impact- overfishing; dumping organic wastes
A deep-sea hydrothermal vent community
MARINE BENTHIC ZONE

33. Tropical rainforest distribution: equatorial precipitation: very wet
temperature: always warm
characteristics: many plants & animals (diverse!), ‘thin’ soil

34. Savanna distribution: equatorial
precipitation: seasonal, dry season/wet season
temperature: always warm
characteristics: fire-adapted, drought tolerant plants; herbivores; fertile soil

35. Desert distribution: 30°N & S latitude band precipitation: almost
temperature: variable daily & seasonally, hot & cold
characteristics: sparse vegetation & animals, cacti, succulents, (CAM plants), reptiles, insects, rodents, birds

36. Temperate Grassland distribution: mid-latitudes, mid-continents
precipitation: seasonal, dry season/wet season
temperature: cold winters/hot summers
characteristics: prairie grasses, fire-adapted, drought tolerant plants; many herbivores; deep, fertile soil

37. Temperate Deciduous Forest
distribution: mid-latitude, northern hemisphere
precipitation: adequate, summer rains, winter snow
temperature: moderate warm summer/cool winter (seasons)
characteristics: many mammals, insects, birds, etc.; deciduous trees; fertile soils

38. Coniferous Forest (Taiga)
distribution: high-latitude, northern hemisphere
precipitation: adequate to dry (temperate rain forest on coast)
temperature: cool year round
characteristics: conifers; diverse mammals, birds, insects, etc.

39. Arctic Tundra distribution: arctic, high-latitude, northern hemisphere
precipitation: dry
temperature: cold year round
characteristics: permafrost, lichens & mosses, migrating animals & resident herbivores

40. Alpine Tundra distribution: high elevation at all latitudes
precipitation: dry
temperature: cold year round
characteristics: permafrost, lichens, mosses, grasses; migrating animals & resident herbivores