Chapter 52: Ecology and the Biosphere Flashcards
Ecology (def.)
Science that studies the interactions among organisms and their environment
Relationship between ecology and evolution?
- Ecologists see products of interaction ver time
Compare/Contrast Evolutionary vs. Ecological Time
- Ecological time faster than evolutionary
- Interactions take place on ecological time scale
- Adaptation takes place on evolutionary time scale
How do ecologists study ecological questions?
- Observation based
- Use experiments
- Ask questions related to each of the three components of definition of ecology
Factors that influence distribution of individuals
- Dispersal
- Habitat selection
- Biotic factors
- Abiotic factors
Biotic factors (def.)
Living factors
Abiotic factors (def.)
Factors that are nonliving (temperature, water, sunlight)
Questions an ecologist might ask to understand what limits distribution?
- Where are they distributed over the region?
- Why are they distributed over the region that way?
What is the most important factor that limits an organism’s distribution?
Climate
Dispersal (def.)
- Organism’s ability to move may limit their distribution
Method to study what affects dispersal?
- Use of species transplants to determine dispersal limits
Habitat selection
- Species might choose to live in a particular area simply because of a preference
Biotic factor examples
Predation and competition
Abiotic factor examples
Temperature, water, sunlight, wind, salinity
Factors that determine climate
- Temperature
- Precipitation
- Sunlight
- Wind
Factors that determine global climate patterns?
- Latitudinal variation in intensity of sunlight
- Seasonal variation in intensity of sunlight
- Variation in sunlight causes patterns in air circulation and precipitation
How does air move?
- Warms and rises (can hold moisture)
- As air rises, pressure decrease, air cools
- Cool air loses moisture
Sunlight intensity over the globe and by season?
- Intensity at equator is highest
- Neither pole is tilted toward the sun
Seasonal variation is greatest at…?
- 90˚N and S latitude
Wind and ocean currents occur how?
- Air in motion plus Earth’s rotation creates global wind patterns
- Wind patterns create great ocean conveyor belt
Regional, local factors that affect climate?
- Oceans and large lakes moderate coastal climate
- Mountains
Large bodies regulate climate how?
- Water evaporates over land during day, at night returns to the ocean
How mountains affect climate?
- Sunlight
- Temperature
- Influence wind patterns, rain pattens
- Aspect (north vs. south facing)
Microclimate (def.)
Determined by fine-scale differences in the environment that affect light and wind patterns
Biome (def.)
Combination of species and climates determine the biome; major aquatic or terrestrial life zones on Earth
Main factors that determine biomes
- Precipitation vs. Temperature
Examples of biomes and their characteristics?
- Savanna: Grassland, some trees
- Desert: Restricted population
- Tundra: poorly productive areas, permafrost, small plants
- Chaparral: Mediterranean areas; just north of equator
What biome is Bozeman?
Northern coniferous forest
Ecotone (def.)
- Region of transition between two biological communities
