Long term research into soil carbon on the Monaro continues
21 Sep 2021
A long running research project looking at soil carbon levels across the Monaro has found that seasonal conditions have the biggest influence on the increase or decrease of the level of carbon stored in the soil under perennial pastures.
Key points:
- Soil carbon levels can vary based on soil type, climate conditions and management practices
- For a given soil type, our research going back to 2009 has shown that seasonal conditions by far have the biggest influence on soil carbon stocks in perennial pasture systems
- Producers should consider managing soil fertility as plant nutrition is a major driver of soil carbon accumulation and has pasture production benefits
“Back in 2009, when we started this project, we had limited knowledge about soil organic carbon and to what degree soil and pasture type, along with farmers’ management decisions influenced its decline or increase.” said Local Land Services senior agriculture advisor Jo Powells.
“The ongoing sampling and analysis have shown that seasonal conditions have the biggest influence on any increase or decrease in the level or carbon stored in the soil.
“We have captured two significant drought periods during this monitoring and the effects on soil carbon have been significant”.
Soil carbon is an important component of soil health and drives many of the soil functions that our production systems rely upon. Soil carbon levels can also be influenced by above-ground vegetation and agricultural management practices as well as seasonal conditions.
“Soil fertility and the supply of soil nutrients such as sulphur, nitrogen and phosphorus have also been found to greatly influence soil carbon sequestration.
“This information is very useful for producers as we can see how the sensible addition of these nutrients can also result in in higher groundcover as well as increased pasture production for livestock so it’s a win-win.”
Thirty one sites across the Monaro have been monitored for changes in soil organic carbon every three years since 2009. The monitoring has included a focus on the influence of local geology (basalt vs granite-derived soils) and pasture systems (native and introduced) on soil carbon levels.
Dr. Susan Orgill, researcher with NSW Department of Primary Industries and the Graham Centre for Agricultural Innovation at Charles Sturt University, started her PhD back in 2008 investigating what influenced the Monaro’s soil carbon.
“The purpose of this work has been to identify the major drivers of soil carbon accumulation in the Monaro region and investigate strategies for producers to increase carbon sequestration under pastures” Dr. Orgill said.
“This year’s sampling will enable us to track changes in soil carbon under better seasonal conditions and identify sensible targets for soil carbon.”
“To date, these sites have provided a unique insight into how nutrients influence carbon accumulation to depth and soil microbial functions”.
The sampling this year will continue to make these sites one of only a handful of continuously monitored field sites under pastures in Australia and demonstrates support for evidence-based decision making at a regional level.
This project is supported by South East Local Land Services through funding from the Australian Government’s National Landcare Program, The Graham Centre for Agricultural Innovation and NSW Department of Primary Industries.
ENDS
Media contact: Jo Powells, South East Local Land Services, 0429 785 986.