Biogeochemical Cycles Flashcards
Biogeochemical cycles
a cycle that traces the pathway taken by chemicals through the biotic and abiotic components of the biosphere.
What reactions allow for carbon and oxygen to be incorporated in living things?
Photosynthesis and cellular respiration
Decomposition
The process of breaking down dead organic matter and releasing the organic nutrients to the soil for reuse
Detritus
Left over remains of organisms (ex: carcass, excreted waste, other organic fragments)
Fossil fuels
formed when detritus is placed under intense heat and pressure, for a longggg time resulting in fossilized organic remains (coal, oil, natural gas)
The greenhouse effect
A phenomenon where infrared (heat) radiation coming from the earth’s surface is trapped by greenhouse gases and cannot escape. As a result, this warms up the atmosphere
What do greenhouse gases include?
water (H2O), carbon dioxide (CO2), methane (CH4), nitrous oxide (NO2), ozone (O3) and
chlorofluorocarbons (CFC’s).
What bacteria is involved in converting nitrogen?
Decomposers, nitrogen fixing, nitrifying bacteria, denitrifying bacteria
Why is phosphorus needed?
To make nucleic acids and ATP, and required for healthy bones and teeth
Which is the only biogeochemical cycle that doesn’t have an atmospheric phase?
Phosphorous cycle
Eutrophication
When decomposers consume a great deal of the water’s dissolved oxygen, making the lake inhabitable for aquatic life
Algal Blooms
Excess phosphate runoff from fertilizers into waterways causes overgrowth of algae.
How do plants get sulfur?
Through the soil
What do decomposing bacteria do in the nitrogen cycle?
break down detritus and release ammonium (NH4+) into the soil
What do Nitrogen fixing bacteria do in the nitrogen cycle?
Bacteria that live in nodules help to grab free nitrogen from the atmosphere and lock it into the soil
The role of nitrifying bacteria in the nitrogen cycle
Convert ammonium (harmful waste) into nitrate or nitrite (good nutrients)
The role of denitrifying bacteria in the nitrogen cycle
Convert nitrite or nitrate back into atmospheric nitrogen (N2)
Why is nitrogen important?
nitrogen is an important component in proteins and nucleic acids
How do humans get nitrogen?
We get nitrogen from plants who get nitrogen from the soil
The hydrological cycle is driven by….?
the sun’s energy
How does runoff in the hydrological cycle help other cycles?
Runoff helps move elements from terrestrial to aquatic ecosystems
Which human activities increase atmospheric CO2 and affect Earth’s climate and oceans?
Burning of fossil fuels and deforestation
Rapid and slow cycling in the carbon cycle
Rapid: carbon exchange among living organisms
Slow: carbon cycling through geologic processes
