carbon cycle Flashcards
what are the linkages in the inorganic carbon cycle?
- volcanism
- solubility pump
- chemical weathering
- subduction
what are the reservoirs in the inorganic carbon cycle?
- oceans
- atmosphere
- rocks
what is volcanism?
melting rocks as a result of intense heat from the interior of the planet that rise towards the surface, reach the crust and emerging into the atmosphere
how is volcanism a part of the carbon cycle?
- carbonate rocks release CO2 when broken down
- CO2 gas is released along with heat and melted minerals during volcanic activity
what is the solubility pump?
the direct exchange of carbon between the atmosphere and the ocean
what happens when CO2 enters the ocean?
- CO2 dissolves in water
- reacts with water to create carbonic acid
- carbonic acid can turn into bicarbonate
- bicarbonate can turn into carbonate
- all these reactions are reversible
what are the steps in chemical weathering?
- CO2 reacts with H2O in the atmosphere -> carbonic acid
- carbonic acid falls with rainwater
- reacts with exposed sedimentary rock
- results in the production of calcium ions and bicarbonate ions
- rainfall washes bicarbonate/calcium ions into the ocean
- calcium ions and carbonate ions combine in solution to form calcium carbonate
- calcium carbonate is used by shell-producing life forms
- calcium carbonate settles on the ocean floor
- forms mineral deposits of calcium carbonate
what is subduction?
when one tectonic plate is pushed under another -> the plate being subducted eventually melts as a result of the heat in the interior of the planet
how does subduction contribute to the carbon cycle?
carbonate rocks from the ocean deposits melt during subduction and convert to CO2 gasses
what are the linkages in the organic carbon cycle?
- photosynthesis
- decomposition
- cellular respiration
- fossil fuels
- biological pump
- anthropocentric linkages
what is humus?
the organic component of the soil composed of partially decomposed organic molecules
what are fossil fuels?
reservoirs of concentrated carbon formed in the ancient geological past from the remains of plant and animal life that did not fully decompose
what are the steps to fossil fuel formation?
- dead organic matter buried by sedimentation before it can be fully decomposed
- increasing build up of sediments
- increasing weight compressing organic matter moving it deeper in the crust
- increasing compression and heat which removes trapped water and gases and transforms larger carbon molecules to smaller ones
- concentrated carbon remains
what happens in the biological pump?
photosynthesis, cellular respiration, decomposition and fossil fuel formation in the marine habitats
how do calcium carbonate deposits get back on land?
through tectonic plate movement
why are there seasonal fluctuations in the carbon cycle?
because photosynthetic rates increase in the spring/summer, taking up carbon diozide and then plant growth slows down in fall/winter so cellular respiration becomes the primary process involving carbon dioxide
what are the three major anthropogenic linkages in the carbon cycle?
- burning of fossil fuels for energy
- changing land use
- creating concrete from limestone
what is the concequence of ocean acidification on shell formation?
- the increasing H+ ions in the ocean bind with the available carbonate making bicarbonate
- this removes the reservoir of dissolved carbonate for the formation of calcium carbonate
- because H+ has higher affinity to carbonate than calcium, existing molecules of calcium carbonate can break appart and shells can dissolve at a low pH
what is the Greening Hypothesis?
carbon dioxide is a fertilizer and when increased, it will stimulate greater plant productivity and expand forests
what is a FACE system?
Free Air Carbon Dioxide Enrichment system
- large scale experimental exposure of plants in real world conditions to elevated atmospheric carbon dioxide levels
what are the results of the FACE experiment?
plants love the CO2 at first exposure and then eventually they run into other limitations
- there are other climatic stressors from climate change that dramatically modify the relationship between increase CO2 and plant growth (like drought and nutrient deficiencies)
what is the Junk Food Effect?
increased sugar production in plants results in decrease in production of other organic molecules and reduction in mineral uptake
- cells only have a finite amount of space!
