Rattan Lal: briefing notes for Copenhagen: The Potential for Soil Carbon Sequestration
WIN-WIN: “Soil carbon sequestration is a win”win strategy. It mitigates climate change by offsetting anthropogenic emissions; improves the environment, especially the quality of natural waters; enhances soil quality; improves agronomic productivity; and advances food security. It is a low-hanging fruit and a bridge to the future, until carbon-neutral fuel sources and low-carbon economy take effect.”
Agriculture and climate change are inextricably linked, and thus, agriculture must be on the Copenhagen agenda. Indeed, it must be on the agenda of negotiators well before COP15. The International Food Policy Research Institute”™s (IFPRI) 2020 Vision Initiative approached leading experts around the world to share their views on the key negotiating outcomes that must be pursued now in order to effectively put agriculture on the climate change agenda. Their perspectives are compiled in a set of policy briefs on “œAgriculture and Climate Change: An Agenda for Negotiation in Copenhagen”, which is available at http://www.ifpri.org/2020/focus/focus16.asp.
The world’s leading soil carbon scholar, has written a briefing paper for the Copenhagen round of negotiations for The International Food Policy Research Institute. In it he has laid down some basic precepts that should inform the debate and lift the level of discussion.
PHOTOSYNTHESIS CAN BALANCE THE CARBON BUDGET: “The natural rate of photosynthesis in the global biosphere is about 120 billion mt of carbon per year. Fossil fuel combustion emits about 8 billion mt of carbon annually, and deforestation and land-use conversion emit another 1.6 billion to 2 billion mt of carbon per year, for a total of 9.6 to 10.8 billion mt of carbon emissions per year. Thus, if roughly 8 percent of the carbon being photosynthesized by the biosphere is retained within the soil and biotic pools, the global carbon budget would be balanced.”
50 YEARS: “The technical potential of carbon sequestration in world soils may be 2 billion to 3 billion mt per year for the next 50 years. Thus, the potential of carbon sequestration in soils and vegetation together is equivalent to a draw-down of about 50 parts per million of atmospheric CO2 by 2100.”
CARBON JUST LIKE ANY OTHER PRODUCE: “One way to think of soil carbon is as a commodity. It can be produced and, if carbon markets exist, traded like any other farm produce. Additional income can be an important incentive for the resource poor farmers in developing countries to invest in soil restoration and adopt RMPs. The economic potential may be as much as 60 percent of the technical potential, or 1.2 to 2.0 billion mt of carbon per year. Furthermore, measuring and monitoring protocols of change in carbon pools at the landscape, farm, and regional scales are available to facilitate carbon trading.”
DEGRADED SOILS HAVE HE MOST POTENTIAL: “The greatest potential for sequestration is in the soils of those regions that have lost the most soil carbon. These are the regions where soils are severely degraded and have been used with extractive farming practices for a long time…”
ONE TONNE CARBON PER HECTARE PER YEAR: “Most soils have a technical or maximum sink capacity of 20 to 50 mt of carbon per hectare that can be sequestered over a 20-to-50-year period.”
COPENHAGEN GOALS: “Suggested negotiating outcomes:
Carbon sequestration in soils and plants is the only strategy that can remove carbon from the atmosphere and, over time, reduce atmospheric concentration of CO2.
Initiatives to support reduced emissions from deforestation (REDD) are well underway.
Funds for soil carbon mitigation should also be made available. Support should be provided for:
“¢ crop mixes to include more plants that are perennial or have deep-root systems in order to increase the amount of carbon stored in the soil;
“¢ cultivation systems that leave residues;
* cultivation systems that reduce tillage, especially deep tillage, in order to encourage the buildup of soil carbon;
“¢ shifting land use from annual crops to perennial crops, pasture, and agroforestry in order to increase both above- and belowground carbon stocks; and
“¢ activities that restore degraded and desertified soils and ecosystems, especially those affected by accelerated erosion, salinization, and nutrient depletion.”
LOW-COST MONITORING: “Carbon offset payments should be allowed for carbon sequestered in soils where low-cost monitoring is available. Funds for the development of these monitoring systems should be part of any outcome.”
Rattan Lal (email@example.com) is Director of the Ohio State University”™s Carbon Management and Sequestration Center and Professor of Soil Science in the School of Environment and Natural Resources.