12-14 September, 2011, Lucknow - Earth Science India

National Conference on Science of Climate Change and Earth’s Sustainability: Issues and Challenges ‘A Scientist-People Partnership’
12-14 September, 2011, Lucknow
SOIL: A NATURAL RESOURCE AS WELL AS AN
IMPORTANT TOOL OF CARBON SEQUESTRATION
M.K. Gupta
Forest Soil & Land Reclamation Division, Forest Research Institute, P.O. New Forest,
Dehradun 248 006.
email: guptamk@icfre.org
Soil is a natural resource and cannot be assumed as a high quality permanent
source of sustainable nutrition for plants. Proper management and utilization of this
natural resources are very important and should be given due priority. Our natural
resources are under tremendous pressure. Our forests are suffering from great pressure
to cater the need of fuel, fodder, timber etc to the large population of the country.
Large-scale deforestation is one of the major causes for increasing CO 2 in the
atmosphere on one hand and depleting nutrients in soil on the other hand. Trees have
the potential to store the carbon for the long time in the wood and thus halting the
depletion of ozone layer. Concentration of atmospheric CO 2 can be lowered either by
reducing emissions or by taking CO 2 out from the atmosphere and stored in the
terrestrial, oceanic or aquatic ecosystems. Soil organic matter contains the largest
terrestrial reservoir of carbon in the biological global carbon cycle. As such, it plays a
major role in the control of carbon dioxide levels in the atmosphere. Soils store 2.5 to
3.0 times as much carbon that stored in plants and two to three times more than the
atmospheric as CO 2. . Soil carbon has much longer residence mean times than the carbon
in the vegetation that the soils support. Changes in forest type, productivity, decay rates
and disturbances can effectively modify the carbon contents of forest soils. Some
reports indicate, up to 87 % decrease in soil organic carbon due to deforestation.
Plantations are consequential to diverting pressure from natural forests by providing
fuel, fodder and timber to the growing population. Soils and vegetation, therefore,
represent potential sinks for this additional carbon and several authors have suggested
afforestation as a possible means of mitigating global climate change. The carbon store
in forest land is the highest followed by agroforestry, agricultural lands and barren
lands. The effect of land use change on soil carbon stock is of concern in the context of
international policy agenda on GHG emission mitigation. Trees enrich the soil through
adding organic matter, nutrient cycling, provide shade to conserve moisture, promote
microbial activities and improve soil physicochemical behaviour. Deforestation results
in increased air movement and facilitates oxidation of organic matter thus emitting CO 2 .
Increase in atmospheric temperature due to climate change is also enhancing the
decomposition of organic matter and release of CO 2 in the atmosphere. Soil organic
carbon is sensitive to impact of anthropogenic activities. There is a major potential for
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