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Acidic soil Soil with a pH of less than 7.
Aeolian deposit Material deposited by the wind.
Alluvial soils Soils developed in recent river, estuary or marine deposits.
Alluvium Material deposited by flowing water.
Available water capacity In soil, the portion of water that can be readily absorbed by plant roots.
Basin peat Poorly drained lowland soils with an organic surface layer more than 50 cm thick. Basin peat generally forms at low levels in distinct depressions.
Blanket peat Poorly drained upland soil with an organic surface layer more than 50 cm thick. It is unconfined and "blankets" the landscape.
Brown soil Moderately acid soils with brown mineral topsoils and brown or yellowish subsoils.
Bulk density The weight of dry soil divided by its volume.
Calcareous soils Relatively thick soils, rich in calcium carbonate.

A chemical element with the symbol C. It is found in all known life.

Carbon dioxide

The most abundant greenhouse gas. It occurs naturally, but the concentration in the atmosphere has increased rapidly since the industrial revolution. Chemical formula is CO2.

Citizen science Scientific work carried out by the general public, often in collaboration with, or under the direction of, professional scientists and scientific institutions.
Clay Clay particles are small particles of soil less than 2 micrometers in diameter. It is also the name of a soil texture.
Climate / climate change Climate is the average weather taken over a long period of time - usually 30 years. Climate change is the change in this average.
Colluvium Material which collects at the foot of a slope.
Compaction When the soil particles move closer together as a result of the weight on top of them. The spaces between the soil particles decrease.
Complex A map unit where soils occur in such a complicated pattern that it is impossible to divide them into individual soil types at the scale of the map survey.
Contamination The addition of contaminants to the soil.
Cryogenic material Material created by the action of freeze and thaw processes.
Cultivated Soil prepared and used for growing plants.
Deficiency Lacking in something important e.g. essential nutrients.
Diffuse pollution Pollution caused by a number of often minor sources of potential pollutants coming together, resulting in environmental damage.
Ecosystem services The benefits the environment produces for people, such as clean air, water, food and materials.
Ecosystems All of the living things (plants, animals, organisms and people) in a given area that interact with each other and their wider environment.
Erosion The movement of material by wind or water.
Fluvioglacial Sediments deposited by meltwater from glaciers.
Food security When all people, at all times, have physical and economic access to sufficient,safe and nutritious food to meet their dietary needs and food preferences (FAO definition).
Gleys Soils that are periodically or permanently waterlogged. They are typically greyish with greenish or blueish tinges and often have a blotchy appearance.
Greenhouse gas (GHG) A gas that traps heat.
Gully A channel cut in the land by water removing the soil. Gullies can vary from 10 cm to more than 1 m deep.
Habitat A particular environment in which specific plants and animals live, depending on the climate, geography, and what plants grow there.
Horizon A distinct layer of soil which runs roughly parallel to the soil surface.
Leaching The loss of soluble materials from the soil, usually caused by water filtering through it.
Legislation A law or set of laws suggested by a government and made official by a parliament.
Lithosols Shallow soils with rock less than 10 cm from the surface.
Magnesian soils Soils with a high magnesium content.
Map unit The basic unit of a soil map. Soils are grouped into map units for display purposes. The map unit is a collection of areas defined and named in terms of their soil components or properties.
Moraine Rocks and sediments transported by a glacier then left behind when the glacier melts often forming ridges or mounds.
National Soil Inventory of Scotland (NSIS) (1978 -1988) The National Soil Inventory of Scotland dataset was collected between 1978 - 88 from locations aranged on a 10 km grid across the country.

A chemical element with the symbol N. It is an essential nutrient for plant growth and protein building.

Nitrous oxide

A greenhouse gas nearly 300 times more powerful than carbon dioxide. It also reacts with oxone in the stratosphere contributing to thinning of the ozone layer. Chemical formula is N2O.

Nutrients Elements or compounds that are essential for all living things.
Parent material The material from which a soil is formed.
Peat An accumulation of partially decomposed organic material, usually formed in waterlogged conditions. Peat soils have an organic layer more than 50 cm deep from the soil surface which has an organic matter conent of more than 60 %.
Pedotransfer function A function that uses information we have, for example soil properties measured from soil surveys, to estimate other soil properties that are more difficult or expensive to measure.
Podzols Acid soils with a grey, leached layer just below the surface and bright orangey-brown coloured subsoils and / or dark brown to black organic rich subsoil.
Policy A statement of intent - a set of ideas or required outcomes and guidance on how to achieve them.
Prime agricultural land Land in Land Capability for Agriculture Classes 1, 2 and 3.1
Profile A vertical section of the soil that show its horizons.
QMUNIT The map unit of the National soil map of Scotland. The QMUNIT is a number identifying a unique combination of parent material, component soil types and associated landforms.
Raised beach A former beach now lying above the shore line.
Rankers Shallow soils more than 10 cm thick with rock near the surface.
Regosols Well drained, poorly developed soils, often with a mineral topsoil and no distinct layering in the subsoil.
Redzinas shallow calcareous soils (rich in calcium carbonate) developed on limestone and more than 10 cm thick.
Saline Soils with a high salt content from sea water.
Scree An accumulation of loose stones or rocky debris lying on a slope or at the base of a cliff.
Semi-confined peat Poorly drained, partly confined soils with an organic surface layer more than 50 cm thick. It is generally formed in valleys, on terraces or between ridges.
Series A soil series is made up of soils with a similar type and arrangement of horizons (layers) which are developed on a similar parent material. The map unit of the Soil map of Scotland (partial cover).
Soil association A grouping of soils developed on similar parent materials.
Soil biodiversity The life within the soil.
Soil classification The arrangement of soils into groups based on their key characteristics.
Soil functions The benefits that soils provide, such as growing food, filtering water and storing carbon.
Soil organic carbon The carbon derived from living and dead plants and animals. It is the principal component of soil organic matter.
Soil organic matter Living and dead plant and animal material in soil.
Soil phase A subdivision of soil series.
Soil sealing The permanent covering of the soil surface with a water-tight material like concrete.
Soil structure The arrangement of soil particles into larger aggregates or clumps.
Soil texture The relative proportions of sand, silt and clay particles.
Thematic maps Any map designed to show a specific theme or subject area

Sediment deposited directly by glaciers usually containing a mixture of materials of different shapes and sizes; because of this is it sometimed called boulder clay.


The upper most layer of the soil.

Water-modified till

A till that has been sorted by the movement of water after it has been deposited.