Assessing microbiome functional traits as indicators of soil health for sustainable agriculture

Soil is a multifunctional environment upon which our food security depends. The ability of soils to maintain particular functions which contribute to ecosystem services (such as food, fibre and energy production) is compromised by soil degradation. This degradation is primarily associated with unsustainable agricultural management practices developed over the past 70 years to maintain optimum productivity of food, fibre, or energy crops. Contrasting land management practices result in variation in soil nutrient availability and / or pH levels, over time this generates distinct microbiomes and functional properties in adjacent soil systems. Not all of these communities or functional properties will be desirable and what is desirable will be dependent on what the land is being used for. Understanding what a healthy and well-functioning soil community looks like in the context of specific land use is of great importance not only to sectors involved in land-based production but also to policy makers driving towards net zero carbon emissions and those wishing to restore degraded land.

The main aim of the project is to use crop rhizosphere microbiome datasets to address the impact of soil management processes on nutrient cycling. A trait-based framework will be used to assign life history strategies to microbiomes which can be used as indicators of soil health. The work will be based on existing rhizosphere microbiomes derived from several major UK crops which have been grown in rotation on soils exposed to contrasting management over several decades at SRUC's Craibstone Campus. Both archive and contemporary soil samples can be used for laboratory and/or glasshouse-based testing to determine actual functional output alongside genetic functional capacity.
The specific questions to be addressed are:
Have decades of contrasting agricultural management established microbiomes with differing nutrient cycling traits based on rhizosphere microbiome datasets?
Do soils have different functional abilities in terms of nutrient mineralisation having been under long-term contrasting management and are these correlated to traits found in the microbiome datasets?
Are there identifiable microbiome markers which can identify soils which will be successful in producing crops in low nutrient input scenarios?