Bio unit 4: ecological systems and population ecology

ecology

study of how organisms interact with each other and the environment

biocenosis

the community of organisms interacting within a particular habitat

organism level

individual organism and its environment

population level

group of individuals of the same species that live in a particular location

community level

populations of different species that occur together in a location and interact with one another form a community

ecosystem level

ecosystems include all the biotic and abiotic interactions within a geographic area

biosphere level

all of earth’s terrestrial and aquatic landscapes make up the biosphere

weather

atmospheric observations down to the minute

climate

weather stats over a period of time

what causes seasonal climate variation?

earth’s axis tilt at 23.5 degrees and earth’s orbit around the sun 

hadley cells

warm air rises at equator and cools air that moves north and south

what influences direction of prevailing winds?

earth’s rotation

upwelling

deep currents returning to the ocean surface with nutrients 

downwelling

colder temperatures and higher salinity causes surface water to sink which forms deep currents and brings oxygen deeper

biome

large community of vegetation and wildlife adapted to a specific climate

convergent evolution

unrelated/distantly related species independently evolve similar traits, often due to adapting to similar environments

factors that influence the current distribution and abundance of organisms 

evolutionary history, geologic history, humans and convergent evolution

2nd law of thermodynamics

when energy is transformed, the quality of energy remains the same but its ability to do work diminishes over time 

photosynthesis 

producers use solar energy to convert co2 and water to glucose (chemical energy) and oxygen (waste) 

producers/autotrophs

organisms that can use solar energy to produce usable forms of energy via photosynthesis

Gross primary productivity (GPP)

total amount of energy produced through photosynthesis

Net primary productivity (NPP)

amount of energy that is usable by other organisms 

NPP calculation 

NPP = GPP - R (respiration) 

ecological efficiency

energy is lost at each trophic level, only 10% is available for consumers at the next level

food chain

simple flow of energy from one level to next

food web

multiple flows of energy connect organisms more realistically 

omnivores

eats animal and plant material

scavengers

eat dead carcasses

detritivores

eat plant detritus

decomposers

eat detritus and organisms like fungus or bacterial communities 

regions with highest productivity have…

higher temperatures and precipitation rates (near the equator)

how does light limit productivity in aquatic ecosystems?

photosynthesis is restricted to surface waters

how do nutrients limit productivity in aquatic ecosystems?

nutrients are limited already in the ocean because organisms like phytoplankton takes it up quickly

pools

reservoirs that store elements (amounts)

fluxes

transfer of energy and materials between pools (rate of movement)

hydrologic cycle fluxes

evaporation, condensation, precipitation, surface runoff

hydrologic cycle pools

lakes, rivers, oceans, clouds, ice, glaciers, etc.

water footprint

the volume of freshwater needed to produce goods and services consumed by an individual, community or other entity 

forms of nitrogen readily used by plants and algae

ammonia and nitrate

how can nitrogen be fixed

lightning strikes, bacteria fixing N2 into ammonia, and human developed method called Haber-Bosch process

human effects on nitrogen cycle

burning fossil fuels, nitrogen fertilizers, farm runoff, all lead to eutrophication

consequences of global warming 

melting of ice caps, sea ice, glaciers, sea level rise, heat waves, weather and climate disasters, and phenology shifts