Soil Organic Carbon Monitoring Project

The Soil Organic Carbon Monitoring (SOC-M) Project is a landmark national initiative designed to quantify decadal changes in soil organic carbon (SOC) stocks across Australia’s agricultural landscapes. Building on the Soil Carbon Research Program (SCaRP, 2009–2012), SOC-M resampled 308 sites representing 7.4% of the 4,180 paddocks surveyed under SCaRP between 2022 and 2025 using a hybrid, model-based site-selection framework. This approach ensured broad environmental and land-management representativeness while accommodating practical constraints, including landholder access.

The project implemented rigorous, standardised field and laboratory protocols aligned with the Australian Government’s ‘2021 Estimating SOC sequestration using measurement and ,models’ method, which is used to generate and issue Australian Carbon Credit Units. These protocols enabled robust measurement of SOC stocks and key SOC fractions, including particulate organic carbon (POC), humus organic carbon (HOC), and resistant organic carbon (ROC). Advanced analytical techniques were employed to characterise SOC composition and enhance predictive capability, notably solid-state ¹³C nuclear magnetic resonance (NMR) spectroscopy and infrared spectroscopy coupled with chemometric modelling. In parallel, SOC-M collated comprehensive land-management datasets, yielding up to two decades of management information for the majority of resampled sites.

Beyond resampling, SOC-M advances open-access benchmark SOC datasets to support cost-effective measurement strategies, improves low-cost sensing and analytical workflows, and strengthens the FullCAM modelling framework used in Australia’s national greenhouse-gas inventory.

This repository contains Version 1 of the SOC-M dataset, together with the associated metadata.