Rothamsted Research - Sustainable Soils and Grassland Systems

Climate Change and Carbon Cycling Research Group

 

Dr. Saran Sohi

Saran joined Rothamsted in 1995 as part of a small team researching soil carbon and nitrogen dynamics. His work defined a procedure for the fractionation of organic matter in soil that could be directly linked to a new simulation model, and led to a PhD by Imperial College in 2001. The unique fractionation-modelling approach has since been implemented as a tool to analyse mineralization pathways in a range of unusual soils. As part of this research Saran spent 2005 at Cornell University, working with colleagues in the Crop and Soil Sciences Department as part of an ongoing, collaborative project exploring the dynamics of black carbon.

Research topics:

Areas of expertise:

  • Developing new models to elucidate processes of C and N turnover in soil
  • Linking fractionation to modelling of soil organic matter dynamics
  • Soil organic matter fractionation techniques
  • Interpreting the composition and reactivity of soil organic matter fractions
  • Evaluating the impact of resource quality on the status of soil fractions
  • Use of soil organic matter fractions as indicators of soil organic matter status

Active collaborations:

Publications:

Papers in refereed journals and books

  • Sohi SP, Mahieu N, Powlson DS, Madari B, Smittenberg R and Gaunt JL. 2005. An investigation of the chemical characteristics of soil organic matter fractions suitable for modelling. Soil Science Society of America Journal 69: 1248 1255
  • Poirier N, Sohi SP, Gaunt JL, Mahieu N, Randall EW, Powlson DS, Evershed RP. 2005. The chemical composition of measurable soil organic matter pools. Organic Geochemistry 36: 1174 89
  • Lopez-Capel E, Sohi SP, Gaunt JL and Manning DAC. 2005. Use of Thermogravimetry–Differential Scanning Calorimetry to characterize modelable soil organic matter fractions Soil Science Society of America Journal 69: 136 140
  • Machado PLOA, Sohi SP and Gaunt JL. 2003. The effect of no-tillage on the turnover of organic matter in a Rhodic Ferralsol. Soil Use and Management 19: 250 256
  • Sohi SP, Mahieu N, Arah JRM, Madari B and Gaunt JL. 2001. A procedure for isolating soil organic matter fractions suitable for modeling. Soil Science Society of America Journal 65: 1121 1128
  • Sohi SP. Dynamic modelling of soil organic matter using physically defined fractions, PhD Thesis, University of London, 254 pp
  • Gaunt JL, Sohi SP, Yang H, Mahieu N and Arah JRM. 2001. A procedure for isolating soil organic matter fractions suitable for modelling. In: R.M. Rees, B.C. Ball, C.D. Campbell, C.A. Watson (Eds), Sustainable Management of Soil Organic Matter, CAB International, Wallingford, pp 90-95
  • Gaunt JL, Sohi SP, Arah JRM, Mahieu N, Yang H. and Powlson DS 1999. A physical soil fractionation scheme to obtain organic matter fractions suitable for modelling. In: G.J.D. Kirk, D.S. Olk (Eds.), Carbon and Nitrogen Dynamics in Flooded Soils, IRRI, Los Banos, pp 89-99
Information products Conference presentations
  • Lehmann L and Sohi SP, Bio-char (black carbon) stability and stabilization in soil. 18th World Congress of Soil Science, Philadelphia, USA, 9-15th July 2006
  • Sohi SP, Yates HC, Liang B, Gaunt JL and Lehmann J. Evaluating C dynamics in terra preta. 18th World Congress of Soil Science, Philadelphia, USA, 9-15 July 2006 (poster presentation)
  • Powlson DS, Sohi SP and Gaunt JL. Managing soil organic matter – possibilities and limitations. Proceedings of the National Tillage Conference, 26th January 2006. Teagasc, Carlow, Ireland, pp 22-3
  • Sohi SP, Gaunt JL, Lopez-Capel E, Yates HC and Lehmann J. Accounting for black C in the modelling of soil organic matter turnover. USDA Symposium on greenhouse gas sources and sinks, Baltimore, USA, 22-24th March 2005 (Oral presentation)
  • Sohi SP, Brett C, Verheijen F, Yaron G, Yates HC, Powlson DS, Kibblewhite M and Gaunt JL. Quantifying the benefits to farmers of managing soil organic matter. ESRC meeting on sustainable farming, Silsoe, UK, 20th April 2004 (Oral presentation)
  • Yates HC, Sohi SP and Gaunt JL. Can an active fraction be used to predict change in total soil carbon in farmers' fields? Workshop on soil organic matter, Rothamsted, December 2004 (Poster presentation)
  • Sohi SP, Arah JRM and Gaunt JL. Can new SOM models further our understanding of organic matter transformation in soil? ASA-CSSA-SSSA Annual meeting, Denver, USA, 1-6th November 2003 (Oral presentation)
  • Sohi SP. Evaluating SOM stabilisation fluxes using the SOMA model. Mechanisms and regulation of organic matter stabilisation in soils. Munich, Germany, 5-8th October 2003 (Oral presentation)
  • Gaunt JL, Sohi SP, Falloon P and Powlson DS. The potential role of dissolved organic matter (DOM) in carbon sequestration. DOM 2001, Bayreuth, Germany 9-12th October 2001 (Oral presentation)
  • Sohi SP, Arah JRM, Yates HC, Macdonald AJ and Gaunt JL. Parameterisation of a soil organic matter model based on measurable fractions. 11th N Workshop, Reims, France, 9-12th September 2001 (Poster presentation)
  • Gaunt JL, Sohi SP, Arah JRM, Mahieu N, Smittenberg R, Ishaque M and Panaullah G. Is all soil organic matter the same? Implications for modelling SOM turnover. Proceedings of BRRI/IRRI workshop on long term soil fertility experiments. BRRI, Gazipur, Bangladesh, 8th-11th March 1999 (Oral presentation)
  • Sohi SP, Mahieu N and Gaunt JL. 13C NMR to verify modelable soil organic matter fractions defined by physical location. 16th World Soils Congress, Montpellier, France, 20-26th August 1998 (Poster presentation)
  • Sohi SP and Gaunt JL. A standardised protocol for the fractionation of soil organic matter. Poster presentation, 9th Nitrogen Workshop, Braunschweig, Germany, 9-12th September 1996 (Poster presentation)