The use of stable isotopes for the assessment and optimisation of conservation agriculture

FAO is engaged in the development of methodologies and tools to analyse win-win options for small farmers aiming at preventing land degradation, enhancing soil fertility, land productivity and carbon sequestration, which contribute to mitigating atmospheric CO2 levels. The conversion from conventional tillage to no-tillage (zero tillage)/conservation agriculture has been suggested as one possible win-win option. Nuclear techniques in particular stable isotopes are extremely useful in the analysis and assessment of the nutrient, water and carbon, inflows and outflows of such complex farming systems. With international networks of experienced scientists and the capacity to train and develop further expertise, the FAO/IAEA is in a unique position to coordinate a global research programme to assess and optimise conservation agriculture systems. A preliminary SWOT analysis was done to explore the issues of undertaking a CRP in this area. The Soils Unit in the FAO/IAEA Laboratory, Seibersdorf, has a range of backup services to offer the CRP, including, quality assurance, isotope analysis and training. In addition the Unit has over 30 years institutional experience of conducting isotope experiments in developing countries. The Unit has conducted extensive research in the areas of: inorganic fertilizer usage, biological nitrogen fixation, measurement of plant N uptake from organic residues, measurement of soil water, and more recently in the areas of: below ground N, carbon cycling, using of the isotopes of water. A number of methods and techniques, which could potentially be used to study conservation agriculture practices will be presented