Soil organic carbon is a complex and varied mixture of materials and makes up a small but vital part of all soils.
The first nationally coordinated program of soil carbon research has gathered a wealth of information on soil carbon stocks that will underpin Australia’s greenhouse gas accounting, carbon farming and sustainable agriculture.
CSIRO scientist, Dr Jeff Baldock and his team have identified four biologically significant types or fractions of soil organic carbon:
crop residues – shoot and root residues less than 2 mm found in the soil and on the soil surface
particulate organic carbon – individual pieces of plant debris that are smaller than 2 mm but larger than 0.053 mm
humus – decomposed materials less than 0.053 mm that are dominated by molecules stuck to soil minerals
recalcitrant organic carbon – this is biologically stable; typically in the form of charcoal.
The Soil Carbon Research Program (SCaRP) was a nationally coordinated program of soil carbon research bringing together researchers from the CSIRO, universities and state government agencies. Funding was provided by the Australian Government’s Climate Change Research Program as well as the Grains Research and Development Corporation (GRDC). The project commenced in April 2009 and concluded in June 2012 and coordinated 13 soil carbon research projects that together establish a strong science basis for soil carbon measurement and accounting and for soil carbon enhancement (sequestration) opportunities.
The SCaRP has been the largest and most extensive soil sampling and analysis program undertaken in Australia to measure stocks of soil carbon. More than 20,000 samples were taken from a wide range of soil types and farming operations across more than 4000 different locations in selected farming regions.
Results from SCaRP are contained in a summary report and reports for each of the 13 national, state or region-based projects.
SCaRP developed a nationally consistent approach to assessing soil carbon stocks for some of the major landuse and soil type combinations used for agricultural production.
The Program realised rapid and cost-effective ways of assessing the total soil carbon, the amount of various forms of soil carbon and soil bulk density.
Land-uses and management strategies with higher soil carbon stocks or potential for enhancing soil carbon were identified at regional level.
Quantification of the inputs of carbon to soils under agricultural systems based on perennial vegetation.
Data for further development of FullCAM, Australia’s national carbon accounting tool, was gathered through the Program.
The Program was established as part of the Australian Government’s Climate Change Research Program within the Australia’s Farming Future initiative. The Department of Agriculture, Fisheries and Forestry and the Grains Research and Development Corporation funded the Program with in-kind contributions from project partners
Project partners were:
Australian Government Department of Agriculture, Fisheries and Forestry
Grains Research and Development Corporation
University of New England
New South Wales Department of Primary Industries
New South Wales Government Office of Environment and Heritage
Victorian Department of Primary Industries
New South Wales Government Murray Catchment Management Authority
Australian Government Caring for Our Country
University of Western Australia
Department of Agriculture and Food of Western Australia
Tasmanian Institute of Agricultural Research
The University of Tasmania and
Department of Environment, Water and Natural Resources of South Australia.