the carbon cycle Flashcards
define sere
a succession that is related to a specific environment
define climatic climax
the final stage of a sere which is reached when the stage of environmental equilibrium is achieved in response to the climate.
describe the local carbon cycle
- in the first seral stage the rock is exposed for the first time due to glacial retreat meaning it is vulnerable to chemical weathering
- weathering slowly breaks the rock down and carbon may be released.
- time allows lichen and moss to establish on the bare rock and photosynthesis and respiration occur as a form of carbon exchange
- organic matter is added to the broken rock due to the decomposition of the lichen and moss. this means a thin soil develops
- small plants will form and the process of the carbon exchange will continues. the decomposition of these plants increases soil depths
- a large species of plants, such as shade intolerant trees, will establish until the ecosystem reaches equilibrium
outline the process of combustion
the process where carbon is burned in the presence of oxygen and converted to energy, carbon dioxide and water.
combustion trasnfers carbon from the biosphere to the atmopshere
wildfires and volcanic activity are natural combustion
buring fossil fuels is human combustion
outline the process of combustion
the process where carbon is burned in the presence of oxygen and converted to energy, carbon dioxide and water.
combustion trasnfers carbon from the biosphere to the atmopshere
wildfires and volcanic activity are natural combustion
buring fossil fuels is human combustion
outline the process of respiration
oxygen in the air and glucose produced through photosynthesis undergoes a chemical process to produce carbon dioxide, water and energy
outline the process of decomposition
the process where carbon from the bodies of dead organisms is transferred from the biospere to the atmospher. decomposition involves physical, chemical and biological mechanisms that break down organic matter. decomposers break down the dead organisms into the substances which the plants need for growth
outline the process of photosynthesis in the carbon cycle
- plants absorb carbon dioxide from the atmosphere
- the carbon dioxide reacts with the chlorophyll in the plants to produce glucose, which is stored as starch
- the plant then emits oxygen as a product of photosynthesis which maintains the balance between oxygen and carbon in the atmosphere
how much carbon in petagrams is stored in each store?
marine sediment and sedimentary rock - 100 000 oceans - 38 000 fossil fuels - 4000 soil - 1500 atmosphere - 750 plants - 560
how does wildfires change the carbon cycle?
- natural wildfires occur in regions which experience hot and arid climates due to increased evaporation rates drawing moisture from the soils, for example along the coastal US state of California where an average of over 8,000 wildfires are experienced annually.
- Wildfires transfer carbon from the biosphere into the atmosphere with 11,6 petagrams of CO2 being released during their combustion. this not only directly increases the levels of atmospheric carbon, it leads to the degrading the quality of the soils below, turning the ground from a carbon sink to a carbon source as the future absorption of carbon is limited. This impacts the overall equilibrium of the carbon cycle as it promotes a positive feedback loop.
how is deforestation impacting the carbon cycle?
- deforestation occurs on a global scale, accounting for approx 20 percent of global greenhouse gas emissions however is particularly concentrated along the tropics in Indonesia.
- the slash and burn technique is utilised in lesser developed countries and results in the addition of 11.6 petagrams of carbon being transferred from the biosphere to the atmosphere
how is urbanisation impacting the carbon cycle?
- as urbanisation experiences a rapid increase over the recent decade due to a rising population of people living in urban areas, there is a rising demand for space. This space is provided through the removal of forest cover through deforestation.
- To power urban expansion, industrial activities are required with urban areas accounting for 97 percent of all anthropogenic CO2 emissions
- urbanisation means more roads and infrastructure are required for the increased amount of transportation. this involves cement production which produces C02 by the use of machinery. cement production accounts for 2.4 percent of global emissions
how is farming practices impacting the carbon cycle?
- fertilisers are used to speed up the growth of crops as well as improve the quality and size of crops however fertilisers have been recorded to account for 60 percent of total emissions at Shimpling Park Farm in Suffolk
- livestock farming has increased due to a higher dependence on meat and dairy products however cattle in the USA emmits 5.5 million tonnes of methane per year. Researchers at the University of Oxford found that cutting meat and dairy products from your diet could reduce an individual’s carbon footprint from food by up to 73 per cent.
what are the inter-relationships between the processes in the water cycle and the carbon cycle?
-carbon can be dissolved in precipitation as rain falls to the earth’s surface as the atmospheric carbon dioxide reacts with the water molecules and forms carbon acid rain.
what is the milankovitch cycle and how does it impact the carbon cycle ?
The MIlankovitch cycles cause regular changes of orbital eccentricity, which varies the amount of solar radiation that heats up the earth as a result of the distance between the Earth and the sun. During periods of eccentricity when the orbit of the sun is undergoing circular rotation, the earth would experience a hotter and more arid climate due to a 20 to 30 percent greater amount of insolation than during a highly elliptical orbit.
