Soil
Soils in the built environment
Introduction
Drivers, functions, definitions
Introduction
Defra is working with partners to achieve the sustainable use and protection of soils in the built environment. The built environment is anywhere where development and construction has occurred (or is planned) and applies to both urban and rural areas.
Drivers
The role of built environment soils and their sustainable use and protection are only now starting to be considered. The rationale for this new focus includes drivers that are:
- Raising the profile of soil protection and use
- Increasing the pressures on built environment soils.
These drivers include:
- EU Thematic Strategy for Soil Protection
- First Soil Action Plan for England: 2004-2006
- Defra Strategic Priority: Protecting Natural Resources
- UK Climate Change Programme
- Sustainable Communities and the review of the planning system.
Soils in the built environment are present in the form of:
- Gardens/allotments
- Open spaces/parks
- Derelict/brownfield land
- Road verges
- School playing fields
- Cemeteries.
They are a spatially complex mixture of natural, imported and man-made (anthrosoils) soils. They have their own classification; contain different materials; and have different properties to natural soil systems.
Function of soils in the built environment
Soils in the built environment will carry out various functions and services for society and need to be protected and managed to optimise these functions.
They will provide all of the six functions to a greater or lesser degree (compared to natural soil systems) depending on their condition.
Most soils will be carrying out more than one function at any one point in time.
They also have a large social function and play an important part in how people live.
Definitions
Natural soils
Natural soils are those that have been formed and developed in place. They may include materials that have been brought in from other areas by natural processes of erosion (water and wind) and deposition.
A natural soil is not necessarily unmanaged or unaltered by man.
Imported soils
Imported soils are soils where the topsoil (and possibly subsoil) is imported from a different location. They are used to supplement or replace the existing soils in an area.
Soils may be imported into the built environment to:
- Replace contaminated soil
- Provide good quality soil for landscaping and gardening.
Man-made soils
Surplus soil is not always available in the quantities and qualities needed for new projects. Or where it is available it may be in the wrong place. The transport of large quantities of soil over long distances is not an economically viable option.
One solution is the creation of man-made soils (anthrosoils). Minerals of different sizes (sands and clays) are mixed with organic matter and fertiliser to form soil.
One example of a project making use of anthrosoils is the Eden Project in Cornwall.
- Eden Project website
Page last modified: 25 July 2006
Page published 1 September
2005