lec 13 carbon cycle pt 2 (last on MT 1)

bodies of living organisms are reservoirs of

carbon

photosynthesis

fixation of inorganic carbon into carbon-hydrogen bonds which store energy for plant and other life forms

cellular respiration

conversion of sugar to ATP releasing gaseous CO2 as a byproduct

decomposition

complex organic molecules broken down into simple compounds, with some carbon deposited as humus

humus composition

partially decomposed organic molecules based on carbon and other elements

fossil fuels

reservoirs of concentrated carbon formed in the ancient geological past from plant and animal remains that didn't fully decompose

fossil fuel formation

sedimentation of dead organic matter, increasing weight moves it to deeper hotter layers, removing trapped water and gases and concentrating the carbon

combustion

any chemical reaction where bonding with oxygen results in the release of energy, producing heat

forest fire cycles

balance carbon lost to combusion with carbon sequestered from photosynthesis of regrowth

peatlands prone to fires because

they are high in carbon, so ground itself is a source of fuel

calcium carbonate deposits in ocean come from

shell-forming marine life

biological pump

same cycle but taking place in the marine habitats

photosynthetic marine life

animals that use CO2 to produce sugars, start the food chain

marine animals release

CO2 during cellular respiration and decompose to possibly form fossil fuels

carbon moves between surface to deep waters through

upwelling and downwelling of dissolved CO2, movement of organisms

cyclical changes in atmospheric CO2

impact of plant life growing in the summer vs dormancy in the winter

anthro linkages

modifying rates of photosynthesis, respiration, combustion, and decomposition

ocean acidification

ocean has increased in acidity by 30%, sink for atmospheric CO2

as number of protons in solution increases

CO₃^2- has a greater affinity for them than Ca²⁺, so this removes the reservoir of dissolved CO₂^2- for calcium carbonate formation

at high enough H+ concentrations

existing calcium carbonate can break down

greening hypothesis

atmospheric CO2 acting as a fertilizer to enhance plant growth

greening reality

initial increase in plant growth, but then a decline over time when other climatic stressors are considered