Chapter 36: Ecosystems Flashcards
Community
- collection of all the organisms living in the same place
- lives in a habitat
Ecosystem
- sum of community and habitat
Producers
- use sun’s energy to make food
Autotrophs
- capture energy from sunlight of chemicals and use that energy to produce food (they are producers)
- Photosynthesis: plants
- Chemosynthesis: bacteria
Consumers
- get their energy directly or indirectly from producers (primary eats plants, secondary eats plant-eating animals)
Heterotrophs
- organisms that cannot make their own food and must rely on other organisms for nutrients and energy
- ex. herbivores, omnivores, carnivores
- Detritivores: feed on plants and animal remains (ex. mites, earthworm, snails)
- Decomposers: break down organic matter (ex. bacteria, fungi)
Food chain v. food web
Food chain: transfer of energy by eating and being eaten
Food web: describes complex relationships and links together all food chains in an ecosystem
Trophic level
- each step of an organism eating another organism
Energy pyramid
- shows relative amounts of energy contained within each trophic level
- only 5-20% of each moves on to next trophic level, lots is lost at each step
6 steps of water cycle
- Precipitation
- Evaporation
- Transpiration
- Condensation
- Percolation
- Runoff
Precipitation
- falling products of condensation in atmosphere
- rain, hail, sleet, snow
Condensation
- water vapor liquifies to form clouds or fog
Evaporation
- changing from a liquid to a gas (water vapor)
Transpiration
- passage of water from plant leaf to atmosphere
Infiltration
- seepage of water into rock or soil
- how water gets back into the ground
Runoff
- surface water that flows into streams when soil is already fully infiltrated
Carbon cycle
- carbon is 4th most abundant element
- all organisms need carbon
- not including water, people are about 1/2 carbon
3 ways carbon is moved through an ecosystem
- Photosynthesis
- Respiration
- Combustion (burning)
Nitrogen cycle
- 78% of air is nitrogen
- all organisms need nitrogen for structure and function but this form of nitrogen is not useable
- Organisms get nitrogen they need by: assimulation, nitrogen fixation, denitrification
Assimulation
- process of absorbing new material (i.e. minerals)
Nitrogen fixation
Process where bacteria can make nitrogen available to plants
- Bacteria found in plant root nodules
- Fertilizers (nitrates, nitrites, ammonia, ammonium)
- Lightning
Denitrification
Releasing nitrogen into the atmosphere
- bacteria in soil
Effect of latitude on climate
- annual orbit and daily rotation
- climate at latitude is relatively constant
- tilt of Earth’s axis causes seasons
- 6 major atmospheric air masses control weather
Rain shadow effect
- when a moving body of air encounters a mountain
- rains heavily on the side it approaches (if coming from ocean), other side is dry
3 main types of ocean ecosystems
- Shallow waters
- Open-sea surface
- Deep-sea waters
3 zones of ponds and lakes
- Littoral zone (shoreline meets water, slopes down)
- Limnetic zone (top center)
- Profundal zone (deep)
Categories of lakes
- Oligotrophic: nutrients and minerals scarce
- Eutrophic: rich in nutrients and minerals
Biome
- terrestrial ecosystem
- ex. tropical rain forest, savanna, desert, temperate grasslands (prairies), temperate deciduous forest, taiga, tundra, chapparal, polar ice, tropical monsoon (upland) forest
