This project was funded by the Australian Federal Government Carbon Farming Initiative (CFI) Action on The Ground program which aimed to assist landholders in trialing new technologies and practices to improve soil and reduce greenhouse gas emissions. Laboratory and field plot research indicated that ploughing nutrients into the soil with crop residues/stubble increased the amount of soil carbon stored. This project tested if this was possible using farm equipment. Carbon sequestration methods were tested in 14 fields in different bioregions. Soil variability was estimated using two electromagnetic surveying instruments. Randomized block experiments were established in fields after areas of similar soil were identified by geostatistics and finite mixture models.

While the field experiments failed to reproduce the high sequestration rates of the earlier more controlled research. We describe one experiment in this paper and propose reasons for this failure to sequester carbon. The hybrid demonstration/research approach is applicable in many other situations where agricultural policy or practice change are to be tested at farm scale.

The data are changes in soil carbon over two or three years and at all 14 experimental sites.