Critical Zone Observatories

The Australian CZO network

Australian Government funding is enabling research into Australia’s critical zone—Earth’s outer skin, from treetop to bedrock, where water, atmosphere, ecosystems, soil and rock interact—to better understand and manage the availability of its life-sustaining resources.

$1.2M of Australian Government funding to a consortium of Australian universities has helped the creation of a network of Critical Zone Observatories (CZO) across Australia.

The funding—part of the Australian Research Council’s Large Infrastructure, Equipment and Facilities scheme (ARC LIEF)—has created a new network of five core and five satellite monitoring sites in five states, sampling a diversity of Australia’s geologies, biomes, land uses and climates.

State-of-the-art, automated monitoring infrastructure at the sites records stocks and flows of carbon, water, energy and mass across the Critical Zone—the vertical span from plant canopies to fresh bedrock.

Collaboration and co-location

The Australian CZO network (OzCZO) is being collaboratively developed and managed by a team of researchers from the University of Western Australia, the University of Adelaide, the University of the Sunshine Coast, James Cook University, and the University of New South Wales. Generous co-contributions to the ARC LIEF funding from these six universities make the project possible.

The NCRIS-funded national research infrastructure projects of TERN and AuScope and parts of the former Groundwater project are also playing leading roles in building and operating the network’s monitoring infrastructure.  TERN is not only associated with six of the ten CZO sites and data but will also make OZCZO data openly available via the TERN data portal.

The initiative adds critical monitoring capabilities missing from existing observation networks, like NCRIS-enabled TERN and the SmartSat CRC’s Earth Monitoring Capability, including soil dynamics, root zones and hydro- and biomantles; and integrated processes between the above- and below-ground components of the Critical Zone.

The critical zone stretches vertically from bedrock to the atmospheric boundary and comprises bedrock, weathered/saprolitic rock, aquifers, soil, the rhizosphere and microbiome in the regolith, habitats, canopies and the nearsurface atmosphere. The CZ provides numerous life-supporting services. OZCZO will enable the integration of understanding across CZ zones, by measuring dynamics relating to water (blue), energy (red), mass (brown), and biotic processes (green).

Filling essential knowledge gaps

The information collected will fill essential knowledge gaps about interactions of under- and above-ground environmental processes and their responses to disturbance and change.  

For example, studies using the OzCZO are expected to provide new insights on ecosystem dependency to below-ground processes and demonstrate how changes to the land surface propagate underground.  OzCZO will also generate new insights into urgent questions such as the fate and stability of carbon in deep soils, how sensitive groundwater recharge and streamflow are to changing vegetation and climate.

These interactions determine the sustainability of food, clean water, mineral resources and Australian ecosystems, and cannot be studied with existing environmental infrastructure.

Australian Government funding will also support the development of a robust, long-term strategy for more effective and collaborative Critical Zone science, helping catalyse Critical Zone science in Australia and joining a burgeoning international movement.

Illustration of OZCZO below-ground and terrestrial CZ observational instrumentation. The mix of pre-existing and new instrumentation shown here is applicable to the OZCZO core sites that are also TERN sites.