apes 1.5 Flashcards
the nitrogen cycle includes the movement of molecules that contain?
nitrogen between sources, sinks, and reservoirs
when sources release nitrogen into atmosphere, what happens?
sinks take nitrogen out of the atmosphere in increasing amounts
How long do nitrogen reservoirs hold nitrogen?
reservoirs hold nitrogen for relatively short periods of time compared to carbon cycle
What is the main nitrogen reservoir?
the atmosphere
Why is nitrogen a critical plant and animal nutrient?
all living things need nitrogen for DNA and amino acids to make proteins
nitrogen fixation
process of N2 gas being converted into biologically available (usable by plants) NH3 or NO3
bacterial fixation
certain bacteria that live in the soil or in symbiotic relationships with plant root plant root nodules convert N2 into ammonia (NH3)
synthetic fixation
humans combust fossil fuels to convert N2 gas into nitrate (NO3)
assimilation
plants and animals taking in nitrogen and incorporating into their body
-plants take in from soil, animals must eat it
ammonification
soil bacteria, microbes and and decomposes converting waste and dead biomass back into NH3 and returning it to soil
nitrification
conversion of NH4 into nitrite (NO2) and then nitrite (NO3) by soil bacteria
Denitrification
conversion of soil nitrogen (NO3) into nitrous oxide (N2O) gas which returns to atmosphere
List 3 Human Impacts
Climate, Ammonia, Leaching or Eutrophication
Human Impact: Climate
N2O (nitrous oxide) = greenhouse which warms earth’s climate
Human Impact: Ammonia Volatilization
excess fertilizer can lead to NH3 gas entering atmosphere
