Download AP Biology, Chapter 50 An Introduction to Ecology and the

AP Biology, Chapter 50
An Introduction to Ecology and the Biosphere
Discovering Ecology
52.1 Earth’s climate varies by latitude and season and is changing rapidly
Intro
1. How do scientists define climate?
Long-term, prevailing weather conditions
Factors: T, precip, sunlight, and wind
Scales
Macroclimate: global to landscape
Microclimate: very fine, localized
Global Climate Patterns
2. Describe how the process of global air circulation maintains latitudinal climatic zones.
Sun's energy is strongest at the equator
Tropical air rises, cools, rains out
Air is drawn to the equator at the surface
Dry air flows away from the equator aloft
3. How does the Earth’s rotation affect global climate patterns?
Once heated air is in motion, rotation acts on it
Air and water form vortexes
Regional and Local Effects on Climate
Intro
4. How are climate patterns affected by seasonality, bodies of water, and
mountain ranges?
Seasonality
Earth’s tilt and revolution varies solar input over the year
Bodies of Water
Coastal currents deliver cold or warm water that moderate climate
Water’s high heat capacity dampens changes
Mountains
Mountain ranges block circulation
Rising moist air rains out; leeward areas are drier
Microclimate
5. Describe examples of factors that affect microclimates.
Forests lessen temperature changes
Low-lying ground is wetter
Rotting logs provide shelter and nutrients for unique communities
6. Distinguish between the abiotic and biotic components of the environment.
Abiotic: non-living; pH, chemical nutrients, humidity, temperature
Biotic: living; competition, predation, parasitism
Global Climate Change
7. Describe evidence for global climate change.
Atmospheric CO2 is increasing
Earth’s surface is warming
Historical description
Glaciers began retreating 16,000 years ago
Tree distributions moved north
8. What limits the ability of species to survive shifts in global climate?
Trees with winged seeds may be able to disperse and survive
Those without may not, like the eastern hemlock
Ex: beech trees
Possible range shifting 8 km/yr
Tree populations move 0.2 km/yr
52.2 The structure and distribution of terrestrial biomes are controlled by climate and distrurbance
Intro
9. How are biomes defined differently in terrestrial and aquatic environments?
Terrestrial: by vegetation type like tropical rain forest
Aquatic: by physical environment like the photic zone
Climate and Terrestrial Biomes
10. How are climographs used to predict predict terrestrial biomes?
Axes: annual mean temperature vs. precipitation
Known biomes form areas within
Overlaps result other factors
Topography, soil, altitude
Pattern of T and precip through the year
General Features of Terrestrial Biomes
11. Describe the characteristics of the major terrestrial biomes: tropical forest,
savanna, desert, chaparral, temperate grassland, temperate forest, taiga, and
tundra.
Tropical forest
Equatorial: consistent high temperature and rainfall
Consistent conditions allow more specialization
Desert
Driest and warmest
Plants adapted for saving water; nocturnal, burrowing animals
Savanna
= tropical grassland; seasonal dryness and fire
Many large grazers
Chaparral
Dry with dense, spiny evergreen shrubs
Periodic fires
Temperate grassland
Seasonally too dry for trees
Periodic fires
Northern coniferous forest or Taiga
Coniferous forest; conical trees shed heavy snow
North or higher than temperate forest
Temperate broadleaf forest
Dominated by deciduous trees; many adaptations for seasonal survival
Vertically layered
Tundra
Cold and dry; swampy in warm season
Permafrost limits tree root penetration
Disturbance and Terrestrial Biomes
12. How does disturbance contribute to the dynamic nature of biomes?
Fires and storms prevent complete succession
Many species are adapted for disturbed areas within biomes
Dominant plants may depend on periodic fires
52.3 Aquatic biomes are diverse and dynamic systems that cover most of Earth
Intro
Zonation in Aquatic Biomes
13. Distinguish among the vertical layers found in aquatic biomes.
Photic: light for autotrophs
Aphotic: no light, no living autotrophs
Thermocline: sharp boundary between warm upper and cold lower
Benthic: entire bottom supplied with detritus
14. How does seasonal turnover maintain diversity in freshwater biomes?
In winter and summer lakes are stratified
Turnover
Spring: warming surface water mixes downward
Fall: cooling sends surface waters downward
Mixing sends oxygen down, nutrients up
15. Define and compare the prominent freshwater biomes.
Littoral: freshwater shore with rooted plants
Stream
Adaptations for the current
Energy from shore plants and detritus
Lake/pond
Oligotrophic: deep, clear, nutrient-poor
Eutrophic: shallow, murky, nutrient-rich
16. Differentiate wetlands and estuaries.
Wetland has little open water; mainly covered with aquatic plants
Estuaries are where freshwater enters saltwater; surrounded by wetlands
17. Define and compare the prominent marine biomes.
Intertidal
Alternately exposed and submerged; subject to wave action
Very stratified on rocky substrates
Coral reef
Warm tropical clear water
Autotrophs: encrusting and symbiotic algae
Oceanic pelagic
Lower nutrients farther from shore
In temperate zones, upwelling brings nutrients
Phytoplankton are the major autotrophs
Deep sea vent
Vents release very hot water with H2S
Chemoautotrophs form the base of food chains
52.4 Interactions between organisms and the environment limit the distribution of species
Intro
18. Order the factors limiting the geographic distribution of species.
Dispersal and Distribution
Intro
Inaccessible or insufficient time to disperse
Inability: flying species disperse more readily
Natural Range Expansion and Adaptive Radiation
Species Transplants
Behavior and Habitat Selection
Habitat selection  least understood
Transplant experiments show dispersal is not the limiting factor
Biotic Factors
Predation, competition, presence of pollinators, etc.
Exotic (invasive) species dramatically show this
Abiotic Factors
Intro
Chemical: water, salinity, pH, nutrients
Physical: light, temperature, soil structure
Temperature
Water and Oxygen
Salinity
Sunlight
Rocks and Soil