primary production

ecology

autrotrophs

• produces own organic food molecules from simple inorganic substances using light or chem energy

• photoautotrophs- use sunlight, h2o, co2> glucose thru photosyn

• chemoautotrophs- derive energy from inorganic chem rxns thru chemosynthesis instead of sunlight

heterotrophs

• cant make own food, so they eat or absorb it

• consumers- all animals, fungi protists/bacteria

compensation point

for plants the eq point at which photosyn=respiration

gross primary production

GPP

total energy captured by plants thru photosyn

primary production/ NPP

actual growth & storage of organic matter available to ecosystem

limiting factorf

• freshwater- Phosphorous concentration, less P=clearer water in lakes

• terrestrial- depends on solar radiation, temp, moisture, N & P limiting nutrients

• aquatic- depth that light penetrates in lake/ocean is critical in defining zone of primary prod in aqautic

• marine- limited by light, nutrient (N, Iron, silica)

heterotrophic respiration

carbon released by decomposition & consumer respiration

co2 returned to atmosphere

autotrophic respiration

carbon used by plants for growth & maintenance

co2 returned to atmosphere

energy flow

• flows 1 way

• decomposers gain energy from all other trophic levels

• producers> primary> secondary> tertiary consumers> decomposers

steady state

• plant growth changes among season

• accepts temporal & spatial variations as normal aspect of dynamics

equilibrium

• largely closed system dominated by internal recycling of elements

• self regulation & deterministic dynamics

• stable end points or cycle

• absence of disturbance