unit 4 carbon

• what % of planets biomass is made of carbon?

  almost 50%
• what % of the body is made of carbon?

  18%
• what is the atmosphere?

  found in atmosphere as carbon dioxide

  travel from atmosphere to earth and living organisms
• what is the hydrosphere?

  carbon stored in oceans/reservoirs and absorbs carbon (carbon sink)
• what is the lithosphere?

  most carbon stored in rocks and sediments
• what are the 2 main gases in atmosphere that contain carbon?

  carbon dioxide and methane
• why has the amount of carbon in atmosphere increased by 36% during last 100 years?

  emissions from vehicles

  power stations burning fossil fuels

  deforestation
• in biosphere, what process creates carbohydrates?

  photosynthesis
• how many metric tons are stored in the biosphere?

  560 billion
• what % of all planets carbon is stored in the biosphere?

  0.0012%
• which global ecosystem has most carbon?

  rainforest and temperate forests
• how many metric tons of carbon is there in atmosphere?

  750 billion
• what % of all planets carbon is stored in atmosphere?

  0.0017%
• what are 2 gases in atmosphere that contain carbon?

  carbon dioxide and methane
• why has the amount of carbon in atmosphere increased by 36% in last 100 years?

  emissions from vehicles

  power stations burning fossil fuels

  deforestation
• what is the pedosphere?

  soils and peats
• what % of planets carbon does pedosphere store?

  0.031%
• what % of peat is carbon?

  60%
• what % of global carbon is stored in hydrosphere?

  38,000 billion

  0.038%
• as part of lithosphere, where is over 99.9% of worlds carbon stored?

  limestone
• what time period does slow carbon cycle operate over?

  100-200 billion years
• what are the key processes of slow carbon cycle?

  chemical weathering of rock

  carbon storage (sequestration) on ocean floor

  tectonic processes and volcanic activity
• where do carbonic acids form?

  acidic rainwater reacts with minerals in rock

  combines co2 and water vapour = carbonic acid
• why is rainfall naturally acidic?

  due to co2 in the air and from industry
• what happens to rocks containing calcium carbonate when coming into contact with acidic solutions?

  acid reacts with stone and wears it away
• what is the process of chemical weathering of rock in slow cycle?

  natural precipitation is slightly acidic at ph 5.6 as volcanic eruptions release co2 into the atmosphere, it combines with water vapour to crate carbonic acid, human activities such as burning fossil fuels increases co2 making precipitation more acidic known as carbonation
• what is 2nd part of chemical weathering in slow cycle?

  upon contact with rocks containing calcium carbonate, limestone, acid rain falls and calcium carbonate is converted into calcium bicarbonate which is soluble and transported into oceans by run off and percolation
• what is the effect of carbonation weathering on a landscape?

  karst landscape - limestone pavements
• what happens to calcium bicarbonate when transported to oceans?

  at bottom of oceans, dissolved inorganic carbon accumulate (sequestration) to form carbonate sediments

  carbonate is used by marine organisms to make their shells
• why do ocean carbonate rich sediments accumulate?

  over millions of years, sediments compact to form rocks (lithification) that make up the upper layer of oceanic crust
• what happens to carbon stored on floor in slow carbon cycle?

  in subduction zones, some of carbon is converted into magma may result in volcanic eruptions emitting co2 back into atmosphere

  each year around 200 million tonnes of carbon is released by volcanos
• how much carbon can move through the fast carbon cycle each year?

  1000-100,000 million metric tons
• what are the key processes of fast carbon cycle?

  diffusion of co2 between atmosphere and ocean

  photosynthesis, respiration and decomposition

  combustion
• how much of carbon in ocean is dissolved?

  7% compared to other 93% is within the organisms that live there
• what is the diffusion part of fast carbon cycle?

  water can absorb co2 and follow pathways of either-

  physical inorganic pump

  biological organic pump
• what is the physical inorganic pump in fast carbon cycle?

  movement of dissolved co2 by thermohaline ocean currents form due to variations in ocean temp and salt content

  carbon can be transferred from surface to deep ocean cold dense waters sink

  or can be transferred from deep ocean to surface known as upwelling
• what is the biological organic pump in fast carbon cycle?

  diffusion of co2 to ocean surface, phytoplankton photosynthesise and use diffused co2 storing it in biomass

  phytoplankton are eaten by zooplankton eaten by other organisms passing carbon in carbs, when organisms respire they release co2

  marine organisms die and sink to floor adding carbon rich sediment to floor which over years can form fossil fuels
• what is photosynthesis?

  biochemical process operating in plants which converts co2 and water into carbs and oxygen
• how does rate of photosynthesis vary?

  during winter, less sunlight, less photosynthesis, less co2 absorbed so co2 remains in atmosphere

  during summer, more sunlight, more photosynthesis, more co2 absorbed so less co2 in atmosphere
• what is respiration?

  chemical reaction that happens in all living cells

  energy his released from glucose so processes for life can happen

  co2 is released back into atmosphere as by product