Page 1 of 8Most carbon in the soil is lost as greenhouse gas (carbon dioxide, CO2) into the atmosphere if natural ecosystems are converted to agricultural land. Soils contain 3.3 times more carbon than the atmosphere and 4.5 times more than plants and animals on earth (1). This makes soils an important source of greenhouse gases but also a potential sink if right management is applied. The use of crop residues for bio-energy production reduces the carbon stocks in cropland. Further the dedication of cropland to bio-fuel production increases the area of cultivated land and thus carbon loss from soils and vegetation.
Pyrolysis of waste biomass can generate fuels and biochar recalcitrant against decomposition. If biochar is returned to agricultural land it can increase the soil’s carbon content permanently and would establish a carbon sink for atmospheric CO2. In this case the use of crop residues as a potential energy source may improve soil quality and reduce greenhouse gas emissions in a complementary not competing way. Biochar is proposed as a soil amendment in environments with low carbon sequestration capacity and previously depleted soils (especially in the Tropics). From previous studies it is known that soil biochar amendments increase and maintain soil fertility (2) and the human-made Terra Preta soils in the Ama-zon prove that infertile soils can be transformed into fertile soils and long term carbon enrichment is feasible even in environments with low carbon sequestration capacity (3).
Read more about the global carbon cycle, climate change, soil organic carbon and our options and prospects to mange this carbon pool by biochar carbon sequestration.
The Greenhouse Effect and Climate Change
Climate change and global warming are two terms used for the predicted and observed increase in temperature. While the current temperature increase is caused by human influence on the earth’s carbon cycle, the greenhouse effect is a naturally occurring process. In fact, without this process life on planet Earth would be rather unlikely. Short-waved radiation from the sun is able to permeate the atmosphere (about 55%). The reflected radiation from Earth’s surface has a longer wave length (infrared). The majority of this outgoing radiation is absorbed by the so called greenhouse gases (such as carbon dioxide, water vapor, methane, and nitrous oxide) in the atmosphere (Figure 1).
This process changes the energy balance of the planet just as the glass roof of a greenhouse. This natural process rises the Earth’s temperature by 33° Celsius to an average of 15° Celsius. The amount of heat energy retained by the atmosphere is controlled by the concentration of greenhouse gases and they are balanced by the action of life. Without life the composition of the Earth’s atmosphere would be different.
Read more about The Carbon Cycle
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