Holt Carbon Project

Holt Carbon Project is a soil carbon sequestration project located approximately 15km southwest of Murray Bridge in the Murraylands region of South Australia. Registered in June 2021, the project covers roughly 202 hectares of agricultural land. The project is situated within the Rural City of Murray Bridge local government area, a region characterized by mixed farming operations, including livestock grazing and cereal cropping.

The project operates under the Measurement of Soil Carbon Sequestration in Agricultural Systems methodology. This method requires landholders to establish a baseline of soil organic carbon through physical soil sampling. To generate Australian Carbon Credit Units (ACCUs), the proponent must demonstrate a measured increase in soil carbon levels over time compared to this baseline. This differs from modeled methods, as credits are only issued based on empirical data verified by subsequent sampling rounds, typically occurring every one to five years.

Environmental conditions in the Murraylands are typically semi-arid. Data from the nearby Murray Bridge weather station indicates a mean annual rainfall of approximately 350mm. The soils in this region are diverse but frequently consist of sandy loams, calcareous earths, and shallow brown loams known as Mallee soils, which can be fragile and prone to erosion if not carefully managed.

To achieve carbon sequestration, the Holt Carbon Project has implemented a suite of management activities. These include altering stocking rates to improve ground cover, retaining crop stubble to protect soil structure, converting to reduced or no-tillage practices to minimize disturbance, and applying synthetic or non-synthetic fertilizers to address nutrient deficiencies. These activities are designed to increase biomass production and improve soil health, thereby driving the accumulation of organic carbon in the soil profile.