Soil Carbon Management: Communicating Science to Policy Makers.
John Kimble1, Carlos E. P. Cerri2, Carlos C. Cerri2, Brent E. Clothier3, H. H. Janzen4, and Pedro Sanchez5. (1) USDA-NRCS-NCSS retired, 151 East Hill Church Road, Addison, NY 14801, (2) Univ de São Paulo, Centro de Energia Nuclear na Agricultura - CENA/USP, Laboratório de Biogeoquímica Ambiental, P.O. Box 96., Piracicaba,, 13400-970, Brazil, (3) HortResearch, Tennent Drive, Palmerston North, 5301, New Zealand, (4) Agriculture & Agri-Food Canada, Box 3000; 5403 1st Ave, Lethbridge, AB T1J4B1, Canada, (5) Columbia Univ, 61 Route 9W, P. O. Box 1000, Palisades, NY 10964
Since the late 1800's fossil fuel use, expansion of cultivated agriculture, and forest clearing have led to an increase in atmospheric CO2 from 260 ppm to current levels >370 ppm (IPCC, 2001). Most of the recent increase in CO2 has been attributed to combustion of fossil fuels for energy and transportation. This increase in atmospheric CO2 potentially impacts climate, as it is a greenhouse gas. Recent models of land use suggest terrestrial systems can mitigate the increase of atmospheric CO2 by sequestering C into vegetation and soils. The estimated amount of C stored in world soils is about 1100 to 1600 Pg, more than twice the C in living vegetation (560 Pg) or in the atmosphere (750 Pg). Hence, even relatively small changes in soil C storage per unit area could have a significant impact on the global C balance. The amount of carbon soils can retain is dependent on several factors. Inherent factors include climate variables (temperature and rainfall) and clay content. Economic analysis suggest that soil carbon sequestration is among the most beneficial and cost effective options available for reducing greenhouse gases, particularly over the next 30 years. Managing soils for C provides additional benefits. The benefits of increasing soil organic C include increased plant productivity and enhanced soil, water, and air quality. In addition, management practices that increase soil C also tend to reduce soil erosion, reduce energy inputs into the soil, and improve soil resources. Because of these and other benefits associated with soil carbon, the opportunity exists to translate soil science to policy makers. However in communicating science the first step is to identify the end users and stake holders of the information. The second step is to determine the kind of information that is needed by the users. Finally the information from scientific study needs to be tailored for the end use needs. Examples will be shared how soil carbon management has been translated to policy makers.