1.1.3 - The Carbon Cycle Flashcards
Define carbon.
Carbon is a basic chemical element that, along with nitrogen, phosphorus and sulphur, is needed by all plants and animals in order to survive. The recycling of carbon is essential for life on Earth. It enables food to be provided for plants and animals and energy sources to be created to fuel industrial development. In recent years there has been much concern about the increasing levels of carbon dioxide in the atmosphere and the impact this is having on climate change.
Define ‘organic matter’
Matter derived from living things, both plant and animal residue.
Define ‘inorganic matter’
Compounds that derive from non-living matter (rocks, gases, fossil fuels)
Define ‘carbon sink’
A store that absorbs more carbon than it releases
Define ‘carbon source’
A store that releases more carbon than it absorbs
Define ‘pedosphere’
The ‘skin layer of the earth, where soils are specified separately from lithosphere
Define ‘sequestration’
The process being captured and held in sedimentary rocks or as fossil duels after millions of years of compacted organic matter falling on the ocean floor
Define ‘hydrocarbon’
An organic chemical compound or hydrogen and carbon that forms the basic of crude oil, natural gas and coal and other important energy sources
Define ‘anthropogenic CO2’
Carbon dioxide generated by human activity
Give 4 facts about the lithosphere
- Over 99.9% of the carbon on earth is stored as sedimentary rocks like limestone or concentrated in fossilised organic remains.
- 0.004% carbon as fossil fuels (coal and natural gas).
- This store has taken thousands-millions of years to accumulate carbon via processes like compaction and sequestration into the geological column.
- Marine sediment and sedimentary rocks contain up to 100 million giga tonnes carbon.
Give 6 facts about the hydrosphere.
- Living organic matter (fish, plankton, bacteria) amounts to 30 giga tonnes. Also stored in organisms such as coral reefs and shelly marine life.
- Organic carbon total = 40,000 giga tonnes carbon.
- Much is on the sea floor compacted into organic-rich sediment like shales.
- CO2 is dissolved in rivers lakes and oceans.
- Covering 71% of the earths surface, accounts for 0.04% carbon.
- Carbon on the ocean surface can be exchanged into the atmosphere (euphotic zone) via photosynthesis from creatures like phytoplankton.
Give 6 facts about the biosphere.
- Peat is the accumulation of partially decayed organic matter like plant litter, and forms in permanently waterlogged conditions.
- Terrestrial biosphere stores about 3,170 giga tonnes carbon.
- Carbon is stored in tissues of living organisms. It is transferred into soil during decomposition and decay.
- 0.004% earth’s total carbon contained in biosphere.
- Deforestation can release CO2 from this carbon sink.
- Soil humus is a dark organic-rich substance originating from decomposition. It gets dispersed through the soil by organisms like earthworms.
Give 5 facts about the cryosphere.
- The tundra regions contains vast stores of carbon.
- Less than 0.01% of earths carbon is frozen.
- Majority of carbon in this store is in the soil of permanently frozen ground (permafrost)
- 1,700 giga tonnes carbon frozen.
- Store has changed over time, as part of a positive feedback loop of released CO2 from ice melt and increasing atmospheric temperatures.
Give 5 facts about the atmosphere.
- Contains just 0.001% of earth’s carbon.
- Mainly stored as CO2, also stored as methane (CH4) gas in smaller quantities.
- Atmospheric carbon estimated at 800 giga tonnes carbon.
- More recently, this store has increased due to industrial activity and vehicles resulting in fossil fuel combustion.
- Carbon reacts with water droplets in air, forming carbonic acid, and results in naturally acidic rainfall.
