nature of ecosystems Flashcards
energy flows
between all organisms in an ecosystem
enter via photosynthesis
gross primary productivity
total amount of energy that producers get from photosynthesis
why is gpp lower than expected
plants will use some energy for respiration
what percentage of radiation do plants absorb from the sun
2-3%
net primary productivity equation
gpp - respiratory loss
what is npp
the energy available for growth stored in the plants dry organic biomass
food chains and webs 3 trophic levels
autotrophs - producers
herbivores - primary consumers
carnivores - secondary consumers
what happens when you go up trophic levels
biomass decreases
90% lost averagely at each level
which level has the greatest retention of biomass
consumer to consumer
- consume more organic biomass than from a small plant
why is biomass lost at each trophic level
respiratory loss
sweating
unconsumable parts of an organism (bones)
homeostasis
movement
types of nutrient recycling
carbon fixation
nitrogen fixation
nitrogen fixation
atmospheric nitrogen converted into nitrogen containing organic compounds by nitrogen fixing bacteria - forms NH4+ ions which can be used by the plant (symbiosis)
carbon fixation
in photosynthesis
assimilating atmospheric inorganic carbon into organic compounds to be used by the plant
characteristics that affect terrestrial ecosystems
climate
soil
topography
climate characteristic
precipitation –> vegitation type
temperature –> plant species
majorly impacts npp
