Fundamentals of Ecology- week 3

how many types of ecosystems are there and what are they?

2. terrestrial and aquatic

primary consumers

feed on producers (rooted plants & phytoplankton). ex: zooplankton

secondary consumers

feed on primary consumers. ex: fish

tertiary consumers

feed on tertiary consumers. ex: turtle

heterotrophic

Organisms that obtain their nutrients or food from consuming other organisms.

competition in ecosystem

life in ecosystem is often about competition for limited resources

what are other critical factors influencing community dynamics that are both physical and geographic?

habitat's latitude. amount of rainfall. topography (elevation). available species

law of tolerance

existence, abundance, and distribution of species in an ecosystem are determined by whether levels of 1 or more physical/chemical factors fall within range tolerated by that species

species and tolerance range

may have wide range tolerance to some factors and narrow range to others

organisms and tolerance

each organism has tolerance in its physical and chemical environment

limiting factor principle

too much or little of any abiotic factor can limit or prevent growth of a population, even if al other factors are at near optimum range or tolerance

precipitation limiting factor

on land. often limiting factor. lack of H2O in desert limits plant growth

soil nutrients limiting factor

mostly phosphorus limiting and nitrogen to

limiting factors in aquatic ecosystems

temperature. sun. nutrient availability. dissolved oxygen

dissolved oxygen

amount of oxygen dissolved in given volume of H2O @ particular temp and psi

salinity limiting factor

amounts of various inorganic minerals or salts dissolved in given volume of H2O

earth's organisms either...

produce or consume food

producers (autotrophs)

make own food

heterotrophs or "other feeders"

relay on other organisms to get food

decomposers

mostly certain types of bacteria and fungi. specialized consumers that recycle organic matter in ecosystems

biodegrading

breaking down

process of decomposing

releases simpler inorganic compound into soil and H2O, producers can take them up as nutrients

ecosystem dynamics

changes in ecosystem structure caused by changes in environment (disturbances) or by internal forces

environmental disturbances and humans

impact of environmental disturbances caused by human activities is as important as changes brought by natural processes

equilibrium

steady state ecosystem where all organisms in balance w/environment and each other

resistance

ability ecosystem to remain @ equilibrium in spite of disturbances

resilience

speed @ which an ecosystem recovers equilibrium after being disturbed

human impact and resilience/resistance

nature of ecosystem may changes and it could lose resilience entirely. process may lead complete destruction or irreversible altering of an ecosystem

energy required by most...

complex metabolic pathways (often ATP) especially those responsible building large molecules from smaller molecules and life itself is energy driven process

what are the 3 ways energy is acquired by living things?

photosynthesis. chemosynthesis. consumption/digestion other living or previously living organisms by heterotrophs

each organism in ecosystem is...

assigned feeding level (trophic)

how is the flow of energy and matter traced?

through food webs

food chain

sequence organisms, each which is source of food from next. determines how energy and nutrients from 1 organisms to another through ecosystem

food web

complex interconnected through food chains. map of life's interdependence

1st trophic level

producers

2nd trophic level

primary consumers

3rd trophic level

secondary consumers

4th trophic level

tertiary consumers

detritivores

feed on plant and animal remains and other dead matter

energy flow pyramid

trophic or ecological pyramid. graphical representation of energy found within trophic levels of ecosystem

what is the bottom and largest level of the energy flow pyramid?

producers. contain largest amount of energy

trophic level and biomass

each trophic level contains certain amount of biomass, dry weight of all organic matter contained in its organisms

ecological efficiency

% of usable energy is degraded and lost to environment as low quality heat. in accordance w/2nd law of thermodynamics

different ecosystems use...

solar energy to produce and use biomass at different rates

gross primary productivity (GPP)

rate @ which an ecosystem's producers convert solar energy into chemical energy as biomass

net primary production (NPP)

rate @ which producers use photosynthesis to store energy minus the rate @ which they use some of this stored energy through aerobic respiration

what's determined by how fast producers can supply the energy found in biomass?

number of consumer organisms

matter is recycled within and between...

ecosystems (nutrient cycles act as nutrient supply systems) cycles occur between following reservoirs: gaseous, hydrological, sedimentary, & biological

biogeochemical cycle

cycles driven directly/indirectly by solar energy. key ones are: H2O, carbon, nitrogen, & phosphorus

reservoirs, nutrient cycles

nutrient cycles. biotic/abiotic storage for nutrient molecule

throughflow, nutrient cycles

nutrient cycles. transfer/flow nutrient through biotic/abiotic reservoir

input, nutrient cycles

nutrient cycles. point of entry nutrient molecule

output, nutrient cycles

nutrient cycles. point exit/transfer of nutrient molecule

residence time, nutrient cycles

nutrient cycles. average time that nutrient molecule remains in reservoir

rate of transfer, nutrient cycles

nutrient cycles. refers to movement into/out of reservoir

water or hydrological cycle

temp ranges within which H2O changes is narrow ---> allows water cycle to occur. high heat capacity, heats up slowly and cools down slowly ---> helps create stability in ecosystem and climate

water molecules in ice

less densely packed

water is general physiological solvent

most biological reactions take place w/solutes dissolved in H2O. plants absorb nutrients dissolved in H2O. most materials transported blood/sap dissolved in H2). oxygen dissolved H2O allows aquatic life

water continuously moves between

abiotic matter (oceans, atmosphere, and land). biotic matter (cycles within and between living organism)

what is water movement affected by?

solar radiation (drives evaporation/transpiration). gravitational energy (evaporated H2O rises atmosphere). kinetic energy (as falls to earth, flows back to sea)

precipitation, water cycle input

water cycle input. affected by global warming deforestation, urban heat islands

throughflow, water cycle input

water cycle input. transfer/flow nutrient through biotic/abiotic reservoir

interception, water cycle input

water cycle input. affected vegetation cover

infiltration, water cycle input

water cycle input. affected change in ground cover

percolation, water cycle input

water cycle input. absorption into soil

ground H2O flow, water cycle input

water cycle input. affected abstraction. artificial aquifer recharge

runoff, water cycle input

water cycle input. affected anything that changes interception and infiltration

evaporation, water cycle output

water cycle output. affected global climate change, reservoirs also impacted

transpiration, water cycle output

water cycle output. affected by changes in vegetation

river/lake channel discharge, water cycle output

water cycle output. affected by abstraction and flood drainage

water cycle reservoirs

oceans (97%). land ice (2%). groundwater (0.7%). lakes, rivers, soil moisture, atmosphere, and living organisms (0.03%)

carbon cycle

major component all organic compounds. only element form long chains atoms. able produce with variety of different compound

where does carbon dioxide occur?

atmosphere. ocean. land. underground

how is carbon returned to the atmosphere?

cellular respiration. geological activity (volcanic eruptions).

how is carbon removed from atmosphere?

photosynthesis. absorption/dissolving in oceans

atmosphere, carbon reservoirs

carbon reservoirs. mainly as CO2

H2O, carbon reservoirs

carbon reservoirs. dissolved CO2 and hydrogen carbonate

plants, animals, dead organic matter. carbon reservoirs

carbon reservoirs. carbs, lipids and proteins

sedimentary rocks, carbon reservoirs

carbon reservoirs. calcium carbonate

fossil fuels, carbon reservoirs

carbon reservoirs. carbon and hydrocarbons

photosynthesis, carbon in ecosystem

carbon in ecosystem. light captured via plant pigments ---> CO2 + H2O converted to carbs ---? oxygen by product

respiration, carbon in ecosystem

carbon in ecosystem. energy released from carbs ---> used drive metabolic processes

aerobic respiration, carbon in ecosystem

carbon in ecosystem. breaks down organic compounds to CO2. releases more energy than anaerobic

anaerobic respiration, carbon in ecosystem

carbon in ecosystem. allow organism survive and use food sources in oxygen deficient environment. releases as methane

food chains, carbon in ecosystem

carbon in ecosystem. passage organic compounds as food between organism

decomposition, carbon in ecosystem

carbon in ecosystem. breakdown dead organic matter by microorganisms, releasing gases under aerobic condition and methane under anaerobic

fossilization, carbon in ecosystem

carbon in ecosystem. incomplete decomposition dead organisms (anaerobic) ---> fossil fuel formation

sedimentation, carbon in ecosystem

carbon in ecosystem. some marine organisms absorb CO2 and store in skeletons ---> later deposited as sediments on seafloor

combustion, carbon in ecosystem

carbon in ecosystem. release CO2 into atmosphere by burning organic substances

volcanoes, carbon in ecosystem

carbon in ecosystem. release CO2 fossil fuels/sedimentary rocks underground

nitrogen cycle

all organisms require nitrogen to make proteins and nucleic acids

how much of the atmosphere is nitrogen gas?

78%

nitrogen fixation

bacteria convert nitrogen into forms (ammonia, nitrates, nitrites) that can be used by primary producers

denitrification

return nitrogen gas to atmosphere by bacteria

atmosphere, nitrogen reservoirs

nitrogen reservoirs. gaseous nitrogen, also some nitrogen oxides.

plants and animals, nitrogen reservoirs

nitrogen reservoirs. proteins

dead organic matter, nitrogen reservoirs

nitrogen reservoirs. proteins break down to release ammonium compounds

soil, nitrogen reservoirs

nitrogen reservoirs. nitrates, nitrites and ammonium compounds

H2O, nitrogen reservoirs

nitrogen reservoirs. dissolved nitrates and ammonium compounds

rocks, nitrogen reservoirs

nitrogen reservoirs. minerals containing nitrogen