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Indicators of the quality of the physical property of soil - SP1611

Description
Soil provides society with vital goods and services (e.g. supply of food, fodder and fibre; storage of rainwater, nutrients and carbon; shelter to diverse living organisms; and protection of our buried cultural heritage). The capacity of soil to perform these functions is often expressed as ‘soil quality’, which is determined by biological, chemical and physical soil properties. As these properties vary in space and time, so soil quality varies. Little is known of these variations, especially at the national scale and under increasing external pressures such as changes in weather patterns and land use. This is why monitoring of the soil properties that affect soil quality (known as ‘soil quality indicators’ or ‘SQIs’) is important. This information is essential if we are to value soil as a non-renewable resource which supports human health and well-being, and ultimately the country’s economic status. Soil monitoring also demonstrates how damage to soil properties by degradation processes (e.g. erosion, loss of organic carbon, compaction, surface sealing and contamination) affects soil quality.

The aim of this project is to provide evidence to support the implementation of a meaningful soil monitoring programme in England and Wales. So far, the development of such a programme has been hindered by the limited number of suitable physical SQIs that have been identified. Previous work has examined a number of physical soil properties and judged their suitability as soil quality indicators (SQIs) against very specific ‘challenge’ or selection criteria. The latest report found only one property, soil bulk density, met these criteria. Despite ‘qualifying’ as a suitable SQI, this property alone does not capture the overall quality of soil. For example, bulk density is not a good indicator of the water transport function of soil, which affects important services such as flood control, crop growth and mitigation of nutrient losses to watercourses. The paucity of physical SQIs represents a significant limitation of current soil monitoring in characterising soil quality. Acknowledging previous work, this project seeks to identify physical SQIs to add to the current limited suite, taking into account:
- Recent advances in scientific evidence
- Improvements in soil measurement, sampling, modelling and statistical techniques, including their cost-effectiveness (e.g. analysis of existing datasets such as the Countryside Survey and National Soil Inventory)
- Developments in soil policy since 2006 (e.g. Soil Strategy for England; Welsh Soils Action Plan; draft EU Soil Framework Directive)

For the same reasons, the challenge criteria previously used to identify which soil properties qualify as meaningful SQIs will also need modification. Using revised challenge criteria may allow some soil properties previously deemed ‘unsuitable’ to now qualify as SQIs; at the same time, current SQIs may no longer meet the revised challenge criteria.

In summary, given advances in research and developments in policy drivers, we will revisit and revise the selection of suitable physical soil properties that characterise soils’ capacity to deliver ecosystem goods and services. These properties will be justified as robust, cost-effective indicators of soil quality that can be used in future soil monitoring programmes.
Objective
The general aim of this project is to develop physical indicators of soil quality to add to the current proposed
suite of indicators for any future national soil monitoring. We aim to identify soil physical properties that indicate
the soil’s capacity to deliver ecosystem goods and services. As such, these soil properties are sound indicators
of soil quality. These indicators are needed for the successful implementation of a meaningful soil monitoring
programme in England and Wales.
This will be achieved by the contractor and sub-contractor by carrying out the following specific evidence
objectives:
Objective 1.1: Collation and review of previous scientific evidence, reports, data, SQI selection criteria and
approach, sampling techniques and monitoring methodologies aimed at identifying salient physical SQIs (by
the end of Project Month 3), in the light of recent scientific advances and developments in soil policy.
Objective 1.2: Identify candidate soil physical properties which meet the specifications required to ‘qualify’ as
meaningful physical SQIs (by the end of Project Month 3).
Objective 2.1: Evaluation of new scientific evidence, reports, data, SQI selection criteria, sampling techniques
and monitoring methodologies aimed at identifying salient physical SQIs (by the end of Project Month 8)
Objective 2.2: Identification of suitable physical SQIs from the findings of Objectives 1.1 and 2.1 above, based
on agreed selection criteria, sound science, statistical robustness and feasible data collection methods (by the
end of Project Month 9)
Objective 3.1: Consideration of the policy relevance of the candidate physical SQIs identified in Work Package
2 (by the middle of Project Month 10)
Objective 3.2: Consideration of the cost:effectiveness of the candidate physical SQIs identified in Work
Package 2 (by the middle of Project Month 10)
Objective 3.3. Hold a workshop for the soil science and soil policy community to find agreement on the salient
physical SQIs identified in Objectives 1 – 3 (by the end of Project Month 10)
Objective 3.4: Selection of suitable physical soil quality indicators (SQIs) to be used for soil monitoring in
England and Wales (by end of Project Month 11).
Objective 4.1: Provide DEFRA Project Manager with monthly updates
Objective 4.2: Preparation & submission of Interim Report on project progress (by the end of Project Month 6)
Objective 4.3: Preparation and submission of Final Report on the findings of Work Packages 1, 2 and 3 (by the
end of Project Month 12)
Objective 4.4: Ensure agreed objectives and specification of the project are met, to time and to budget
Project Documents
• FRP - Final Report : SP1611 final report   (1698k)
• ANX - Annex : SP1611 WP1 report   (612k)
• ANX - Annex : SP1611 WP2 report   (2571k)
• ANX - Annex : SP1611 WP3 report   (308k)
Time-Scale and Cost
From: 2011

To: 2012

Cost: £96,025
Contractor / Funded Organisations
Cranfield University
Keywords
Soil