An extensive three-week field sampling program for sequestered carbon was successfully completed at DeGrey Station in the Pilbara during May.
As a comprehensive benchmark study, it aims to provide pre-trial data on sequestered carbon stocks so that the effect of the changed management can be assessed in the future on the upcoming grazing trial (more on that next month).
Rangelands NRM Senior Rangeland Scientist Dr Peter Russell said the work will also enable land system ‘characterisation’ to be undertaken in regard to the distribution and density of above-ground (plant biomass) carbon.
Biomass sampling was undertaken by a team of 13 people on 58 sites distributed across the trial area and adjacent non-trial (or control) area over a combined area of approximately 100,000 hectares. Plant measurements were made and samples were collected for laboratory analysis, at an average rate of five plots per day.
Each plot is temporary and consists of a 625m2 area (25m x 25m), demarcated with survey tapes, within which most of the work is done.
“Everyone worked exceedingly well as a team to get the immense amount of work done very expediently,” Dr Russell said.
The biomass samples have now been delivered to the laboratory and field data compilation and statistical analysis has commenced. The below-ground (soil-hosted) carbon will be sampled in August.
During the sampling period, a Field Demonstration Day was also held, on 16 May.
“Interested visitors were given a briefing on the Carbon Awareness Programme, some results of previous work and an explanation of the DeGrey Project, and then, in the field, watched a plot being set up and sampled,” Dr Russell said.
All members of the field team contributed to explanations of the ‘how’ and ‘why’ samples and measurements were taken.
“Of course there were field challenges including localised heavy rain producing soft ground conditions on the alluvial plains and a severe storm threat, triggering temporary evacuation as a precaution from our otherwise idyllic camp by Bibberene Lake,” Dr Russell said.
The carbon work at DeGrey is funded by Royalties for Regions and is a continuation of our Carbon Awareness Programme under which similar work has been undertaken at Meka and Yoweragabbie Stations in the Murchison region in 2013.
This programme is collecting fundamentally important information essential for those considering carbon credit projects in the future, and will eventually be used in the calibration of remotely-sensed carbon estimates. Remote-sensing should dramatically reduce the cost of estimating carbon stocks.
“This is an exciting, producer-driven, commercial-scale trial of several new technologies integrated with an ecological-approach to stock management,” Dr Russell said.
Results from this trial and from smaller satellite trials on other stations will have application throughout the DeGrey River catchment and broader Pilbara region.
Learnings will be distributed through the DeGrey LCDC Producer Group.
Image: George Woolston undertaking Soil Surface Condition assessment at DeGrey Station (©P Russell)