topic 6.3.1: ecosystems Flashcards
how is energy lost between trophic levels
respiration and excretion
what is the equation for biomass efficiency
biomass transferred/ biomass intake x100
how is biomass measured
dry mass/ given area
how can humans manipulate transfer of biomass
-restricting movement
-higher energy food
-keeping warm
-removing competition/predators
N2
atmospheric nitrogen
NO2-
nitrite ions
NO3-
nitrate ions
NH2
amine group
NH3
ammonia gas
NH4+
ammonium ions
what are the 5 stages of the nitrogen cycle
fixation, nitrification, assimilation, ammonification, denitrification
fixation
N2 -> NH3
symbiotic relationship
anaerobic
rhizobium
fixes nitrogen inside root nodules
azotobacta
fixes nitrogen in soil
nitrification
NH3 -> NO2- -> NO3-
oxidation
nitrosomonas
ammonia to nitrites
nitrobacters
nitrite to nitrate
assimilation
NO3- -> NH2
ammonification
NH2 -> NH3
saphrobionts and detritivores
denitrification
NO3 -> N2
reduction, anaerobic
soil
carbon cycle- photosynthesis
fixed during calvin cycle (rubisco carboxylates rubp)
carbon cycle- sedimentation
dead plants form layers of sediment, storing carbon
carbon cycle- respiration
released from link and krebs, and fermentation
carbon cycle- decomposition
detritivores feed on dead matter
saprophytes decay dead matter
carbon released
what is succession
change in ecological community over time
3 stages of primary succession
pioneer comm, intermediate comm, climax comm
pioneer community
colonies bare rock or sand, adapted for harsh abiotic factors, forms humus, low range and short life cycle
intermediate community
mosses and smaller plants survive, increased nutrient content of soil
climax community
trees, larger range, longer life cycle, outcompetes previous species, most stable
deflected succession
human activity prevents climax community
