Carbon sequestration possibility in Nepal

Carbon sequestration is defined as 'The process of removing carbon from the atmosphere and depositing it in a reservoir'.It may also be a geoengineering technique for long-term storage of carbon dioxide or other forms of carbon to mitigate global warming. It has been proposed as a way to mitigate accumulation of greenhouse gases in the atmosphere, which are released by burning fossil fuels.

Carbon dioxide is usually captured from the atmosphere through biological, chemical or physical processes.CO2 may be captured as a pure by-product in processes related to petroleum refining or from flue gases from power generation. CO2 sequestration can then be synonymous with the storage part of carbon capture and storage, which refers to large-scale, permanent artificial capture and sequestration of industrially produced CO2 using subsurface saline aquifers, reservoirs, ocean water, aging oil fields, or other carbon sinks.

Sequestration techniques do not provide instantaneous results; the fact that they will take a long time to make a difference in CO2 levels must be taken into consideration. These levels are expected by the IPCC to be higher than today's.

Biosequestration or carbon sequestration through biological processes has had a huge effect on the Global carbon cycle.[citation needed] Major climatic fluctuations have been driven by these processes in the past, such as at the Azolla event, which created the current Arctic climate.[citation needed] Such processes created fossil fuels, as well as clathrate or limestone. By using certain techniques to manipulate such processes, geoengineers seek to enhance sequestration. Methods such as ocean iron fertilization are examples of such geoengineering techniques.

Iron fertilization of the ocean to encourage phytoplankton growth, which removes carbon from the atmosphere on a temporary, or arguably permanent basis.This technique is controversial due to difficulties of predicting its effect on the marine ecosystem,and the potential for side effects or large deviations from expected efficacy. Such effects potentially include release of nitrogen oxides, and disruption to the nutrient balance in the ocean. Iron fertilization is a natural process, and the enhancement of this process is the geoengineering technique.

Reforestation is the replanting of trees on marginal crop and pasture lands to transfer CO2 from the atmosphere to new biomass.For this process to be successful it is essential to ensure that the carbon does not return to the atmosphere from burning or rotting when the trees die. To this end, it would be important to either manage such forests in perpetuity or use the wood from them for biochar, bio-energy with carbon storage (BECS) or landfill.

Globally, soils are estimated to contain approximately 1,500 gigatons of organic carbon, more than the total of carbon in vegetation and the atmosphere.Modification of agricultural practices is a recognized method of carbon sequestration as soil can act as an effective carbon sink offsetting as much as 20% of carbon dioxide emissions annually.[citation needed]. Carbon emission reduction methods in agriculture can be grouped into two categories: reducing and/or displacing emissions and enhancing carbon removal. Some of these reductions involve generally increasing the efficiency of farm operations (i.e. more fuel-efficient equipment) while some involve interruptions in the natural carbon cycle. While a wide variety of carbon control techniques are possible within agriculture, not all have the same degree of effectiveness, and the degree of effectiveness can also vary considerably when the normal variations in farming such as location, climate, weather, plant varieties, etc. are considered. Also, some effective carbon sequestering techniques (such as the elimination of stubble burning) can negatively impact other areas of environmental concern (increased use of chemicals to control weeds not destroyed by burning).

Many of the carbon reduction techniques used in other industries are also applicable to agriculture. Also, any increases in the efficiency of farming methods that result in higher yields will generally result in reduced emissions as well, since more food is being produced for the same or less effort. This includes more accurate use of fertilizers, better irrigation, and the use of higher yield crop strains such as those bred for locally beneficial traits and those selected for increased yields.

Replacement of more energy intensive farming operations with less energy intensive versions that accomplish the same task can also reduce emissions. Reduced or no-till farming requires less machine tillage and correspondingly less fuel burned per acre of production. However, increased use of weed-control chemicals are usually required for no-till farming operations and the extra residue left on the soil surface is more likely to release its CO2 to the atmosphere as it decays, reducing the net carbon reduction.In practice, most farming operations that incorporate post-harvest crop residues, wastes and byproducts back into the soil will provide a carbon storage benefit.[citation needed] This is particularly the case for practices such as field burning of stubble - rather than releasing almost all of the stored CO2 to the atmosphere, tillage incorporates the biomass back into the soil where it can be absorbed and a portion of it stored permanently.

Hope work on carbon sequstration will be further more enhanced in Nepal also.

For details please visit: http://en.wikipedia.org/wiki/Carbon_sequestration