Fundamental bases of biological soil resilience

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Soils underpin our civilisation, since we rely on them to provide a wide range of goods and services such as food production, water storage and purification, nutrient cycling, support for biodiversity and a platform on which we reside. However, they are constantly subjected to stresses and pressures which may compromise their ability to deliver these functions. Such pressures are increasing as a result of the accelerating demands placed on soils, compounded by climate change. Healthy soils can be defined as those that are able to deliver the range of desired functions, withstand such pressures applied to them, and recover from such challenges - in other words, soils need to be resilient. We know little of what actually makes soils more or less resilient, and what the mechanisms are which govern such behaviour. We think it may be related to a combination of their inherent properties (i.e. what they comprise), and external factors (such as their position in the landscape and the way they have been managed). We propose to identify which are the key properties of soils that relate to their resilience. Our approach will be to consider a particular soil function related to the biological activity of soils, which is indicative of many of the more general functions that soils carry out. We propose to take soil samples from a wide spread across England so that we have a big range in basic properties and circumstances, and determine their resilience in the laboratory using a technique which measures biological activity following perturbation arising from drying and wetting cycles. Knowing both the soil properties and the associated resilience, we can then explore the relationships between the two. We think that it is unlikely that resilience is due to one particular soil characteristic, but a combination of factors. In order to elucidate such relationships we will develop and apply a combination of mathematical and statistical approaches which are suited to such tasks. The results will let us then establish both what it is that underpins soil resilience, and also the extent to which we may be able to impart resilience onto soils, for example by how we manage them. We will also use the data to produce a prototype map of soil resilience for England, which will be informative in terms of identifying which soils are more or less robust and therefore may need particular approaches to ensure the maintenance of their health. This proposal addresses the Living with Environmental Change initiative by developing understanding of the ways in which soils may be managed to resist environmental change.