Ch 52 - Introduction to Ecology & the Biosphere Flashcards
1
Q
Describe the levels of ecological organization.
A
- Population - ex: population of bison
- Community - interactions between populations (ex: between wolves & bison)
- Ecosystem - all populations in community (grass, wolves, bison) and abiotic factors (pH, etc)
- Biome - climatically and geographically defined as contiguous areas with similar climatic conditions
- Biosphere - the global sum of all ecosystems.
2
Q
Describe global climate patterns.
A
- Latitudinal Variation in Sunlight Intensity - sunlight hits the tropics most directly so more heat is delivered there; comparatively at higher latitudes the sunlight hits at a low angle and heat is more diffuse.
- Seasonality - the Earth rotates on a tilted axis around the sun; results in changes in day length, light intensity, and temperature - most pronounced in mid-high latitudes.
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Air circulation & precipitation patterns:
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Warm, wet air flows from tropics to poles:
- At equator & 60°: Warm air rises, cools, & loses moisture. Results in: tropical rain, temperate forests.
- At 30° & poles: Cool dry air sinks, reheats, & sucks up moisture. Results in: desert zones, dry tundra.
- Global wind patterns: cooling eastern tradewinds, warm westerlies.
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Warm, wet air flows from tropics to poles:
3
Q
Describe regional/local climate patterns.
A
- proximity to water: coastal areas usually wetter, large bodies of water buffer temperature on land nearby, but does not necessarily cool coastal areas.
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mountains:
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warm, water-laden air cools as rises over mountains:
- condenses as rain/snow on windward side
- cool dry air warms as travels down leewaerd side
- this dry air creates rain shadow as absorbs moisture from ground
- changes in altitude on mountain is similar to changes in latitutde
- as altitude increases so does temperature
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warm, water-laden air cools as rises over mountains:
- ravines & valleys: at night, cold air descends downhill into valleys, in morning air warms and flows uphill.
4
Q
Describe what is required for life.
A
- Nutrients to build tissue
- Energy to power all functions
- Water for metabolism
- Suitable temperature for metabolism
5
Q
Describe limiting requirements for life in aquatic and terrestiral environments.
A
Terrestrial: temperature & rainfall
Aquatic: energy & nutrients
6
Q
Describe the tropical forest biome.
A
- Equatorial & subequatorial
- Lots of competition for light
- Highly stratified (layered)
- Highest animal diversity
- Human population growth threatens tropical forests due to agriculture & development
7
Q
Describe the desert biodome.
A
- 30˚ N & S latitudes & in interior of continents
- Low precipitation
- Lots of variation in temperature
- Cold or hot
- Long-distance transport of water/deep water wells have allowed humans to urbanize and develop agriculture in desert environments reducing bio-diversity.
8
Q
Describe the **savanna **biodome.
A
- Equatorial & subequatorial
- More seasonal variation than tropical forests
- Inhabitants include plants adapted to drought/fire, large grazing mammals, lots of insects
- Cattle ranching, over hunting, and too frequent fires set by humans threaten biome
9
Q
Describe the chaparral biome.
A
- Mid-latitude coastal regions.
- Fire & drought resistant plants
- Insects, browsers, reptiles, small animals.
- Highly seasonal: cold, rainy winters & hot, dry summers
- Conversion to agriculture and urbanization, and human made fires are a threat to this biome.
10
Q
Describe the temperate grassland biome.
A
- Mid-latitude on many continents; interiors
- Cold, dry winters; hot, wet summers; periodic drought
- Large grazers, burrorwers, insects
- Conversion to farmland is a major threat to this biome
11
Q
Describe the northern coniferous forest.
A
- Largest terrestrial biome
- Long, cold winters; warm to hot summers
- PNW coast range is exception to precipitation rule and gets exceptionally more rain
- Logging is a threat to this biome
12
Q
Describe the temperate broadleaf forest.
A
- Mid-latitudes in northern hemishphere and parts of New Zealand and Austrailia
- Year-round precipitation
- Long, cold winters; hot, humid summers
- Very diverse wildlife and plants have distinct vertical layers
- Logging and land clearing for urbanization are threatening this biome
13
Q
Describe the tundra biome.
A
- Long, cold winters
- Short, cool summers
- Arctic tundra gets less rain than apline tundra
- Has a layer of perma frost resulting in mostly herbaceous vegetation
- Large grazing mammals and their predators, migratory birds, soil arthropods
- Oil and mineral extraction threatens this biome.
14
Q
Describe the lake biome.
A
- Standing bodies of water
- Shallow, well-lit littoral zone with rooted & floating aquatic plants
- Deeper, farther limnetic zone with microorganisms
- Profundal (deep) zone fed by detritus (waste)
- Can be eutrophic: nutrient rich, oxygen poor; high primary productivity
- Can be oligiotrophic: nutrient poor, oxygen rich; limited primary productivity & lots of fish
- Agriculture runoff and dumping of waste by humans leads to nutrient enrichment which casuses algae blooms, oxygen depletion, and death of fish
15
Q
Describe the streams & rivers biome.
A
- Streams are cold, clear, swift, narrow with rocky bottoms
- Rivers are warmer, turbid, wider with silty bottoms
- Salt & nutrients increase from headwaters to mouth
- Human pollution degrade water quality and kill microorganisms, damming and flood control impair natural functioning as well as threaten migratory animals.
