Sources and sinks

Any livestock enterprise will have activities that emit greenhouse gases, for example, methane produced during animal digestion of feed. There may also be activities that lock up or sequester greenhouse gases out of the atmosphere. These include the sequestration of carbon through the growth of trees or through practices that increase the amount of carbon in soil, such as improved pasture growth. Activities that emit greenhouse gases are called “sources” and activities that sequester greenhouse gases are called “sinks”.

This Quick Start Carbon Calculator will estimate your “sources” of greenhouse gases. It will also estimate any greenhouse gases your enterprise is sequestering through on-farm tree growth (“sink”). The Quick Start Carbon Calculator assumes that at average pasture growth, the carbon sequestered by the pasture and the carbon metabolised by soil organisms are at equilibrium. Therefore, no sequestration of soil carbon is assumed.  

Once you have entered your data for “sources” and “sinks”, there will be a net emissions estimate produced for your enterprise, simply “sources” minus “sinks”. The Quick Start Carbon Calculator will also estimate how much extra pasture growth (to enhance soil carbon) or how many more trees would need to be added to your enterprise to balance out “sources” with these “sinks”. Balancing sources of greenhouse gases with sinks of greenhouse gases within the farm is called insetting.

If you already have more “sinks” than “sources”, the Quick Start Carbon Calculator will let you know.

Data checklist

This Quick Start Carbon Calculator is designed to minimise the amount of data that you will need to get a reliable estimate of your on-farm emissions, but you will need some data to get a fairly accurate idea. Like with most data, the better the quality of the input, the more informative the output can be. However, if you lack accuracy in your data, choose an average that best describes your farming business. You will be able to select from drop-down lists in most instances. Please use the checklist below to ensure you have enough data to enter in the next section on “Farm Information”.