2/1/20161 Soil Carbon Sequestration Methods and Tools for Measurement, Monitoring and Verification Charles W. Rice University Distinguished Professor Department of Agronomy K-State Research and Extension Global economic mitigation potential for different sectors at different carbon prices IPCC, 2007 Non-OECD ET OECD World Total Energy Supply Transport Buildings Industry Agriculture Forestry Waste US$/CO 2 -eq 1 Gt CO 2 -eq Agriculture A large proportion of the mitigation potential of agriculture (excluding bioenergy) arises from soil C sequestration, which has strong synergies with sustainable agriculture and generally reduces vulnerability to climate change. Agricultural practices collectively can make a significant contribution at low cost By increasing soil carbon sinks, By reducing GHG emissions, By contributing biomass feedstocks for energy use IPCC Fourth Assessment Report, Working Group III, 2007 Agricultural management plays a major role in greenhouse gas emissions and offers many opportunities for mitigation Cropland Reduced tillage Rotations Reduced bare fallow Increased intensity Cover crops Fertility management Water management Grasslands Grazing management Fire management Fertilization Measurement, Monitoring and Verification Detecting soil C changes Difficult on short time scales Amount of change small compared to total C Methods for detecting and projecting soil C changes Direct methods Field measurements 6 2/1/20166 Estimating Changes in Soil Organic Carbon Issues Choice of baseline Comparison to current practice Start and end time points Measure C sequestration or avoided C loss Uncertainty and cost in estimating soil C Measure and report mean and variation Seasonality Soil sampling Depths Roots Carbonates Rocks 7 Sampling strategies: account for variable landscapes 8 Spatial variability influences estimates of soil organic C n 100 samples to detect 2-3% change in SOC n 16 samples to detect % change in SOC Garten and Wullschleger (1999) Ogle et al. (2003) 10 2/1/201610 11 12 Geo-reference microsites n Microsites reduces spatial variability n Simple and inexpensive n Used to improve models n Used to adopt new technology n Soil C changes detected in 3 yr 0.71 Mg C ha -1 semiarid 1.25 Mg C ha -1 subhumid Ellert et al. (2001) Soil C sequestration No-till continuous corn, started in 1990 14 Monitoring and Verification LevelResolutionCost Practiced Based Individual Fields 15 Measurement, Monitoring and Verification Methods for detecting and projecting soil C changes Direct methods Field measurements Indirect methods Accounting -Stratified accounting -Remote sensing -Models Post et al. (2001) 16 Methods to Extrapolate Measurements and Model Predictions from Sites to Regional Scales n Models CENTURY Comet VR EPIC RothC Other models are also being developed n Spatial aggregation of soil carbon distribution Remote sensing and climatic data Indices: Productivity Practice monitoring 17 Resources Available for National-level Assessments NRCS/STATSGO soil data Daily Climate data from NOAA 1997 NRI area weights NRCS/ERS Cropping Practices Survey NRCS/National Soils Laboratory Pedon Database 18 Crop identification for spatial modeling. Courtesy: P Doraiswamy, USDA-ARS, Beltsville, MD Remote Sensing and Carbon Sequestration n Remote sensing cannot be used to measure soil C directly unless soil is bare n Remote sensing useful for assessing Vegetation Type Cover Productivity Water, soil temperature Tillage intensity? In Situ Measurements of Soil Carbon with Advanced Technologies R.C. Izaurralde, M.H. Ebinger, J.B. Reeves, C.W. Rice, L. Wielopolski, B.A. Francis, R.D. Harris, S. Mitra, A.M. Thomson 20 Mid-Infrared Reflectance Spectroscopy: MIRS McCarty et al. (2002) Soil Sci. Soc. Am. J. 66: Laser Induced Breakdown Spectroscopy: LIBS Cremers et al. (2001) J. Environ. Qual. 30: Portable Non-destructive method measurement of C in soils In Situ Measurements of Soil Carbon with Advanced Technologies 21 New Technologies Laser Induced Breakdown Spectroscopy: LIBS Mid-Infrared Reflectance Spectroscopy: MIRS 22 Conclusions n By using principles of soil science Minimize spatial variability Reduce number of samples Decrease costs Increase efficiency Increase sensitivity for detecting change Allow adoption of new technology n Extrapolation Modeling Remote sensing 23 n WebsitesK-State Research and Extension Chuck Rice Phone: Cell: