Measuring soil microbes

There is increasing recognition amongst farmers and scientists alike that soil biology is an important component in crop and pasture production and ecosystem health. However, measuring soil biology can be confounding and analysing the data even more so.

Scientific advances have resulted in new ways to measure the diversity, abundance and function of soil microbiota. Landholders wish to better understand how they can use this information to manage the soil biology for better ‘soil health’ for example by minimising chemical inputs, changing cropping practices, or sequestering carbon.

This project will apply a range of soil biology metrics that have been proposed as indicators of soil health, and assess their relevance to agronomic or environmental outcomes, such as crop yield, soil structure and nutrient availability.

Samples will be taken from diverse regional areas, across seasons to determine whether relationships between indicators and functions can be generalised, or whether they are site or seasonally specific. This will improve knowledge of the soil microbial indicators that drive agronomic decision-making to increase agricultural productivity and resilience to environmental stresses such as drought.

Soil CRC projects have established field experiments evaluating systems-based management practices and use of amendments for addressing soil constraints. This project will value-add to these projects by clarifying which soil microbial indicators consistently provide relevant indices of ‘soil health’ across time and space.

Indicators will be classified and ranked in terms of their relationships to specific, farmer-identified production and ecosystem target outcomes. Farmers will be able to use soil microbial indicators to benchmark and monitor changes to soil health over time which will inform management decisions, resulting in more cost and time efficient practices.