What are the consequences of elevated Carbon Dioxide on soil organic carbon pools?
Soil organic carbon is the largest reservoir of organic carbon in the terrestrial biosphere. Change in atmospheric CO2 could affect soil carbon storage through changes in plant and microbial activities.
High amounts of plant-based carbon are kept in tundra environments. The photosynthesis can increase based on increased temperature but past a certain point the temperature with optimize photosynthesis and the respiration of the organic matter can increase so rather than have soil organic matter increase the respiration or decay is more and the soil organic reserve decreases.
Thawing of tundra permafrost could lead to release of significant amounts of soil organic matter reserves to atmospheric greenhouse gas. If permafrost areas would convert into forests the dynamic might reduce the GHG because of increase hard biomass and increased soil organic.
The thawing of frozen lakes in many areas is liberating significant amounts of methane also.
Under our present scenario fossil fuels are driving greenhouse gases principally but our human activities can also lead to soil organic matter accumulation and afforestation or grassland expansion which can all work to counteract our present excess of greenhouse gases.
Organic carbon sequestered in soil aggregate contributes significantly to the carbon preservation on the earth’s surface. However, the turnover of soil aggregate in high latitudes and cold zones is strongly affected by the frequency of freeze–thaw cycles and may be disturbed by climate change. Although the effects of recurrent freeze–thaw cycles on...
A great effort in global change research has recently been directed towards assessing the potential of soil as a C sink under future CO2 scenarios. Considerable attention has been focused on the impact of elevated CO2 on mycorrhizae, particularly arbuscular mycorrhizae (AM), assuming that stimulation of mycorrhizae by e...