Ecosystems & Biomes Flashcards
Ecosystem
The living and non-living things in an environment
EX: a neighborhood
2 Starting Points of Energy
- the sun
2. earth’s core
Photosynthesis
Opposite of cellular respiration
Anabolic (small molecules combined)
Energonic (stores energy)
Only in producers
Cellular Respiration
Opposite of photosynthesis
Catabolic (molecules broken)
Exergonic (releases energy)
For plants & animals
Autotrophs
Trap energy from sunlight and use it to synthesis starch / glucose in process called photosynthesis
Producers
Chemosynthesis
Used by “special producers”
Get energy from earth’s core
Make food via chemical reactions
EX: extremophiles
Consumers
Heterotrophs must obtain nutrients from plants & other animals
Herbivores
Only eats plants
EX: cows, rabbits
Carnivores
Only eat meat
EX: snakes, lions, owls
Omnivores
Eat both plants and animals
EX: humans, bears
Scavengers
Eats scraps, do not hunt
EX: gulls, vulture
Detritivores
Breaks down decaying plant / animal material through chemical
EX: bacteria, fungus
Prey
An animal that is hunted by another for food
EX: salmon
Key feauture is eyes on side of their face to watch their environment
Predator
Organism that primarily obtains food by killing & consuming other organisms
EX: grizzly bears
Key feature is front facing eyes to narrow in on prey
Gaia Hypothesis
Living organisms interact with their inorganic surrundings on Earth to form a self-regulating complex system that helps to maintain and perpetuate the conditions for life on the planet
- life maintains conditions suitable for its own survival
Trophic Levels
Position that organism occupies in food chain / position group of organisms in community occupy in food chains
Trophic Level 1
Producer
Trophic Level 2
Herbivore
primary consumers
Trophic Level 3
Carnivore / Omnivore
secondary consumer
Trophic Level 4
Carnivore
tertiary consumer
Food Web
Chain that is interconnected with other organisms
Pyramid of Biomass
Relationship of the mass (amount) of organisms
Pyramid of Numbers
Records number of individuals at each trophic level
Energy Pyramid / Pyramid of Productivity
Shows flow of energy throughout each trophic level
First layer (autotrophs) have the most energy
Only 10% of energy in one trophic level is transferred to the next due to loss in heat & metabolism
Zonation
How an ecosystem changes over an environmental gradient
Niches
Change with
- altitude
- temperature
- precipitation
- solar insolation
- soil type
- species interactions (including humans)
Bioaccumulation
Build up of persistent or non-biodegradable pollutants within an organism
Biomagnification
Patterns of toxic buildup as trophic levels increase because they cannot be broken down
- can disrupt flow of energy in ecosystem and lead to collapse
Primary Succession
Occurs on bare abiotic surfaces (no soil) Stages: Bare land 1. Colonization - Pioneer Organisms 2. Establishment 3. Competition 4. Stabilization 5. Climax Community
Secondary Succession
Occurs when an established ecosystem is destroyed (soil still developed and present)
EX: fire, flood, human activity
Stages:
1. Seeds blow in & cover ground
2. Smalll shrubs start to colonize
3. Eventually trees establish resulting in mature soil & climax community
Biome
Collection of ecosystems sharing similar climactic conditions
5 Major Biomes
- Aquatic (freshwater & marine)
- Forest (tropical, deciduous, coniferous)
- Grassland (savanna, temperate)
- Desert
- Tundra (arctic & alpine)
Why Biomes Form There
- Altitude: higher you rise from sea level, colder the temperaure
- Ocean & wind currents: distributes heat energy from equator back into poles
- Precipitation to Evaporation ratio: when the same, P/E ratio is about 1, soil is rich and fertile
Tropical Rainforest
Location: - near equator Abiotic factors: - little variation in temperatures - no distinct seasonal changes - high biodiversity & biomass - hot & moist - about 100 in/yr of rainfall Biotic factors - plants grow in layers - animals are specialists - many symbiotic relationships Threats: - logging, cattle ranching - civilizations of people without homes Promote sustainable use of rainforests' products
Savannas / Grasslands
Location: - tropics Abiotic Factors: - amount of precipitation supports tall grasses but only occasional trees - rainy & dry season - fire plays large role in plants resistance to drought - plants w thorns & sharp leaves against predation - animals migrate to follow scarce food Threats: - invasive species - changes in fire management - rises in sea level (global warming)
Desert
Location: - depends Abiotic Factors: - little to no topsoil due to high winds - minerals not deep in soil - too dry for decay - cannot support grass - hot days & cold nights Biotic Factors: - vegetation (cacti) waxy coating & shallow roots - animals (camel, cobras, lizards) (many nocturnal to avoid light) Threats: - residential development - offroad recreational activities - some plants removed by collectors
Steppe / Prairies
Location: - Russia, Ukraine, US - dry, cold, grasslands Abiotic Factors: - low precipitation, high winds - mountains Biotic Factors: - plants grow in bunches to preserve water - many migrate, hibernate, burrow during extremes in temp & precipitation Threats: - overgrazing - infastructure development - unmanaged hunting & poaching
Chaparral
Location: - coastal areas w Mediterranean climate Abiotic Factors: - climate = hot, dry summers mild, wet winters - slight variations in seasonal temperatures Biotic Factors: - camouflage to avoid predation - animals change diet as season changes Threats: - human development
Temperate / Deciduous Forest
Location: - temperate zone - much of human population lives here Abiotic Factors: - deep soil layers, rich in nutrients - precipitation (snow, rain, hail, fog, etc) - abundance of deciduous trees - 4 seasons Biotic Factors: - more ground dwelling plants (more sun) - animals adapt to seasons (shed coat, hibernate, etc) Threats: - deforestation Careful use of resources
Taiga: Coniferous / Boreal Forest
Location: - northern hemisphere Abiotic Factors: - winters long & cold - soil poor in nutrients & very acidic - short growing season Biotic Factors: - plants have needles (conifer trees) - animals have thick coats and hibernate during extreme cold Threats: - mining operations - pollution
Tundra: Ice Caps
Location: - north of Arctic Circle Abiotic Factors: - temp rarely higher than 10º C - permafrost layer - short growing season Biotic Factors: - plants with shallow roots - short trees - animals wth small ears, insulation, thick coat Threats: - one of most fragile biomes - oil drilling
Freshwater Ecosystems
Abitoic Factors: - low / no salinity - lakes are deepest of fresh water system, fed by underground aquifer / streams - ponds fed by rainwater & may be seasonal Biotic Factors: - plants are floating (algae) - animals live in / by water Threats: - pollution
Marshes and Swamps
Abiotic Factors: - water recharge areas, removing pollutants - watertypes = brackish, freshwater - found on flat, poorly drained land - often near streams - very shallow w land occasionally exposed Biotic Factors: - large trees / shrubs - adapted to muddy soils Threats: - backfilling / clearing for farmland
Rivers
Abiotic Factors:
- cold & highly oxygenated
- as it flows it will broaden out, warm up
Biotic Factors:
- unique life at dif points bc of water depth & temperature
Threats:
- disposing of waste products
- runoff from homes = changes in acidity, pollution
- dams alter water flow
Estuaries
- where fresh & saltwater meet
Threats: - pollution from ports
- humans
Coral Reefs
Abiotic Factors: - close to equator - consistent water temp Biotic Factors: - most diverse aquatic ecosystem Threats: - temp is essential, not too hot, not too cold - human intrusion (scuba diving) - pollution
Oceans
Abiotic Factors:
- open ocean = one of least productive areas on earth
- covers nearly 3/4 of earth’s surface
Biotic Factors:
- organisms vastly different depending on zone
