Biogeochemical Cycles

what 4 organic compounds is carbon found in?

Carbs, DNA, fats & protein

how much of co2 accounts for tropospheric gases?

.083%

how does c02 contribute to the earth's thermostat?

if there is too much co2, the earth will warm and if the carbon cycle takes too much away, it will cool.

two processes that have the greatest influence on tropospheric concentrations of CO2 on a monthly or yearly basis?

diffusion of co2 in the atmosphere into the ocean and burning of fossil fuels.

what are the 2 largest sinks for carbon?

continental rocks & ocean sediments

how do oceans play a role in regulating co2 levels?

-Some of atmosphere's CO2 dissolves in ocean and some photosynthesizing producers of ocean remove some. Also ocean water can put the CO2 back into the atmosphere by warming the waters.

Describe the two major anthropogenic interventions in the carbon cycle.

1. humans deplete trees faster than they can reproduce.

2. add co2 through burning fossil fuels & wood

What 2 organic compounds is nitrogen found in?

Nucleic & amino acids

what are 2 ways that nitrogen is fixed?

biological fixation & lightning

Nitrogen Fixation

specialized bacteria in soil and aquatic environments convert gaseous nitrogen→ ammonia→ ammonium ions that is used by plants. N2→ NH3→ NH4+

Nitrification

this happens to ammonia that is not taken up by plants. 2 step process: specialized soil bacteria convert most of NH3 & NH4+ in the soil to nitrite ions which are toxic to nitrate ions which are beneficial for these plants and edible for animals.

Ammonification

groups of specialized decomposer bacteria convert the organic substance to simpler substance containing nitrogen inorganic compounds (NH3 & NH4+).

Denitrification

This nitrogen is converted from NH3 to NH4+ and then into nitrogen gas (N2) and the process begins again.

Describe two anthropogenic interventions in the nitrogen cycle

1. we add nitric acid into the atmosphere--> acid rain

2. we add nitrous oxide into the atmosphere through livestock--> depletion of the ozone in the stratosphere

Which organic compound is sulfur found in?

SO42-, H2S, and SO2

two largest storage areas for sulfur

minerals, ocean sediments & underground in rocks

2 major human activities for sulfur

1. burn sulfur-containing coal and oil to produce electric power

2. ppl convert sulfur into copper, lead & zinc

Which organic compound is phosphorus found in?

DNA and ATP

Explain why phosphorus does not circulate in the troposphere to a great extent

Due to soil conditions not allowing bacteria to convert chemical forms of phosphorous into gaseous forms

Identify the largest sinks for phosphorus

Ocean sediments & terrestrial rocks

Phosphorus is typically found in what ionic form?

Phosphorus is found in PO43-.