Participants of LANDMARK team not only come from different countries, speaking different languages, but also reflect quite different scientific disciplines and professional arenas. While definitely a merit in its own right, these differences can also create confusion as far as the terminology is concerned. This glossary intends to establish common ground for the LANDMARK project and will also been used by other projects and European Commission initiatives.  The glossary might be reshaped during the project, we therefore welcome all your comments and proposals

Please find below the INTERACTIVE GLOSSARY or click on the green button in order to download the pdf version in your language (full deliverable here):







  • E horizon

    Albic horizon, which is an eluvial horizon with evidences of losing soil components; it is usually a light-coloured subsurface horizon from which clay and free iron and aluminium have been removed to the extent that the colour of the horizon is determined by the colour of the sand and silt particles rather than by coatings on these particles.

  • Ecosystem service

    Benefits (provisioning, regulating, supporting and cultural services) that people obtain from ecosystems, including attributes and processes through which natural and managed ecosystems can sustain ecosystem functions (

  • Edaphon

    The community of soil organisms (microbes, fungi, nematodes, worms, insects, protozoa, etc.)

  • Effective rainfall

    (1) The rainfall useful for meeting plant water requirements. This does not include water percolating down to aquifers, or surface runoff of water (cf. definition (2)!)
    (2) The difference between precipitation and evapotranspiration, i.e. the water percolating to aquifers or surface runoff (cf. definition (1)!).
    (3) The amount of rainfall after subtracting the fraction that has been directly evaporated from the canopy surface without reaching the soil surface (as in coniferous forests).

  • Effective rooting depth

    The soil depth from which a fully grown plant can easily extract most of the water needed for transpiration. It can be limited by physical (e.g. cemented pan) or chemical (e.g. saline horizon) properties.

  • Electrical Conductivity (EC)

    Measure of a material’s ability to accommodate the transport of an electric charge and used as a measure of the salinity of the soil, and to estimate practical consequences for crops. EC of a soil suspension at a given soil to water ratio (usually 1:5 or saturated extract as a proxy to soil solution), expressed as Siemen per m.

  • Environmental Zones (EnZs)

    Climatic Zones or Environmental Zones (EnZs, following Metzger et al., 2005)


  • Erosion

    The wearing away of the land surface by water, wind, ice, gravity or other natural or anthropogenic agents that abrade, detach and remove soil particles or rock material from one point on the earth’s surface, for deposition elsewhere, including gravitational creep and so-called tillage erosion.

  • Eutrophication

    Process through which a waterbody, such as a lake or a soil solution, becomes enriched with dissolved nutrients. This can be natural, but is often due to pollution. Eutrophication may result in algal blooms which finally promote anaerobic conditions which may harm fish life.

  • Evaporation

    The rate of water loss from liquid to vapour (gaseous) state from an open water, wet soil or plant surface, usually expressed in mm day–¹.

  • Evapotranspiration

    The process by which water passes from a liquid to a vapour (gaseous) state through transpiration from vegetation, and evaporation from soil and plant surfaces. The rate of evapotranspiration is usually expressed in mm day-¹; a distinction can be made between the potential evapotranspiration under unlimited availability of water and the actual evapotranspiration under limited availability.

  • Exhaustion

    The gradual depletion of reserves of nutrients and organic matter in soils.

  • Exposure

    Compass orientation of a slope.

  • Extensification

    The process of decreasing the use of capital and inputs (e.g. fertilizers, pesticides, machinery, energy) relative to land area. Due to a decrease in inputs per land area the pressure on the environment may be decreased. A decrease in pesticides used, for instance, is likely to decrease the risk of pesticide run-off in surface and groundwater (‘loss per unit area’). However, the actual effect of a decrease in the use of inputs on the environment does not only depend on the amount of inputs used but also on how they are applied and the extent to which decreased inputs lead to lower production (‘loss per unit produce’). Therefore, extensification does not necessarily lead to an environmentally more benign situation.



  • Green manure

    Non-harvested crop grown in between two main crop seasons, intended to improve the soil fertility, generally not growing under N limitation due to the use of fertilizers and manures, or the ability to fix atmospheric N.

  • Ground Cover (GC)

    The most widely used agronomic practice in Conservation Agriculture (CA), whereby the soil surface between rows of annual or perennial crops remains protected against erosion. With this technique, at least 30% of the soil is protected either by sown cover crops, spontaneous vegetation or inert covers, such as pruning residues or tree leaves. For the establishment of sown cover crops and the spread of inert covers, farmers must use methods in coherence with CA principle of minimum soil disturbance.

  • Groundwater

    Freshwater found beneath the earth’s surface that fills the cavities of the earth’s crust (pores, crevices, etc. in soil, sand and rock) contiguously, – and that supplies wells and springs, excluding the water in the vadose (unsaturated) zone. The definition applies to all permanent and temporary water deposits, formed both artificially and naturally, of sufficient quality for at least seasonal use. Groundwater supplies are replenished, or recharged, by rain and melting snow, depending on climate conditions. They can usually be recovered from, or via, an underground formation.

  • Growing season

    The portion of the year when soil and air temperature allow biological activity; this period can be approximated by the number of frost-free days.



  • Immobilisation

    Conversion of water-soluble elements into organic compounds by soil biota.

  • Indicator

    An instrument (measurement, dataset, model, expert elicitation system) for quantifying an attribute, providing quantitative information of the system. For instance, the protocol for soil sampling and pH (KCL) measurement is an indicator for the ‘soil pH’, and the extraction, counting, identification of nematodes and calculation of the maturity index is an indicator for the ‘nematode community in the soil system’. Note that this definition differs from the daily practice where, for example, the pH or the nematode community as such, and not the protocol, is seen as the indicator.

  • Infestation

    Accumulation of agents able to promote biological stress and subsequent loss of yield such as nematodes, weeds, microorganisms, mice, etcetera, favoured by, for instance, a too narrow crop rotation.

  • Infiltration

    The movement of water passing the soil surface into the soil (as contrasted with percolation, which is movement of water through soil layers moving down to the aquifers, or out to rivers).

  • Infiltration capacity

    The maximum rate at which water can infiltrate into a soil under a given set of conditions.

  • Infiltration rate

    The speed at which water can pass into the soil, being typically lower in wet clay than in dry sand (unless sand has become hydrophobic).

  • Inorganic fertilizers

    Mineral, synthetic, industrial, artificial or manufactured fertilizers.

  • Intensification

    The process of increasing the use of inputs (labour, information, energy, fertilizers, pesticides, machinery) relative to land area, to increase agricultural production per unit area. Intensification may increase the pressure on the environment, if it is comprised of an indiscriminate increase of the use of inputs without an associated increase in managerial input. A higher use of fertilizers and pesticides, for instance, may increase the risk of nutrient and pesticide run-off into surface and groundwater (‘loss per unit area’). However, the actual effect of the use of inputs on the environment does not only depend on the amount of inputs used but also on how they are applied and the extent to which they contribute to production increases (‘loss per unit produce’). Therefore, intensification does not necessarily need to lead to environmental degradation.

  • Intercrop

    A crop grown amidst a main crop or in between the planting rows of that main crop and intended to be harvested or to be supportive to the harvest of the main crop.

  • Irrigation

    Application of water to soils to assist in production of crops.


  • Land cover

    The observed (bio)physical cover of the Earth’s surface. The main classes in the LUCAS land cover nomenclature are as follows (

    Classes Nomenclature
    A00 Artificial land
    B00 Cropland
    C00 Woodland
     D00 Shrubland
     E00 Grassland
     F00 Bareland
     G00 Water
     H00 Wetland
  • Land take

    Increase of settlement areas over time. This process includes the development of scattered settlements in rural areas, the expansion of urban areas around an urban nucleus (including urban sprawl), and the conversion of land within an urban area (densification).

  • Land use

    The socio-economic purpose of the land. The main classes in the LUCAS land use nomenclature ( are as follows:

    Classes Nomenclature
    U110 Agriculture
     U120 Forestry
     U130 Fishing
     U140 Mining and quarrying
     U150 Hunting
     U210 Energy production
     U220 Industry and manufacturing
     U310 Transport, communication networks, storage and protective works
     U320 Water and waste treatment
     U330 Construction
     U340 Commerce, finance and business
     U350 Community services
     U360 Recreational, leisure and sport
     U370 Residential
     U400 Unused

    Note: Within the framework of the LANDMARK project only Agriculture (U110) and Forestry (U120) will be considered

  • Leaching

    Removal of soluble materials from one zone in soil to another via water downward movement in the profile.

  • Livestock Unit (L(S)U)

    A reference unit which facilitates the aggregation of livestock from various species and age as per convention, via the use of specific coefficients established initially on the basis of the nutritional or feed requirement of each type of animal (see table below for an overview of the most commonly used coefficients).
    The reference unit used for the calculation of livestock units (=1 LSU) is the grazing equivalent of one adult dairy cow producing 3 000 kg of milk annually, without additional concentrated foodstuffs.
    LU’s as derived from the LUCAS land use nomenclature (

    Bovine animals
    Under 1 year old 0,400
     1 but less than 2 years old  0,700
    Male, 2 years old and over 1,000
    Heifers, 2 years old and over 0,800
    Dairy cows 1,000
    Other cows, 2 years old and over 0,800
    Sheep and goats 0,100
    Equidae 0,800
    Pigs Piglets having a live weight of under 20kg 0,027
    Breeding sows weighing 50kg and over 0,500
    Other pigs 0,300
    Poultry Broilers 0,007
    Laying hens 0,014
    Ostriches 0,350
    Other poultry 0,030
    Rabbits, breeding feemales 0,020





  • Natural capital

    Refers to both the living (e.g. fish stocks, forests) and non-living (e.g. minerals, energy resources) aspects of nature which produce value to people, both directly and indirectly. It is this capital that underpins all other capital in our economy and society. Natural capital can often be confused with ecosystem services. However, whilst similar concepts, they are fundamentally different. Natural capital refers to the actual stock (living and non-living parts) that provides value whereas ecosystem services refer to the flow of benefits that this stock provides. Essentially, natural capital is about nature’s assets, whilst ecosystem services relate to the goods and services derived from those assets (

  • Nestedness

    This is a specific feature of LANDMARK deliverables from WP3 (i.e. the harmonization of proxy indicator systems among different spatial and temporal scales). One of the means to realize this is to collect indicators, and/or proxies, which have overlap for use at different spatial/temporal scales. For instance, land use as proxy should be useful for the EU/national and at the regional scale, while crop rotation should be useful for the regional and farm scale.

  • Nitrification

    Conversion of ammonium-N into nitrite-N and nitrate-N by soil biota.

  • Nitrogen (N)

    NO3      N x 4.43 = NO3

    NH4      N x 1,29 = NH4

  • No tillage (NT)

    An agronomic practice in Conservation Agriculture (CA) for annual crops, and is defined as a way to farm without disturbing the soil through tillage. NT must leave at least 30% of area covered by plant residues right after crop establishment, and crops are sown using machinery which is able to place seeds through plant residues from previous crops. The agronomic practice that best characterizes CA for annual crops is NT, which has the highest degree of soil conservation in annual crops, since the mechanical tillage of the ground is completely suppressed. Also, in arid climates it enhance water retention in soils through decreasing evaporation losses from the soil surface which is usually enhanced by tillage involving soil invert.

  • Nurse crop

    Main crop under which an undersowing is established which accompanies the main crop during at least a part of its growing season.

  • Nutrient Cycling

    The capacity of a soil to receive nutrients in the form of by-products, to provide nutrients from intrinsic resources or to support the acquisition of nutrients from air or water, and to effectively carry over these nutrients into harvested crops.

  • Nutrient recovery

    Fraction of plant-available nutrients from fertilizers and manures taken up by the crop in harvestable fraction(s) and above ground residues, usually excluding roots and stubbles.


  • O horizon

    A surface horizon, or a subsurface horizon occurring at any depth if it has been buried, that consists of poorly aerated organic material. It is usually undecomposed or partially decomposed organic matter (litter such as leaves, needles, twigs, moss, and lichens) (WRB, 2006). Often referred as the histic horizon (from Greek histos, tissue).

  • Organic farming

    Agricultural production which typically places a higher emphasis on environmental and wildlife protection and, with regard to livestock production, on measures that are supposedly animal welfare friendly. Organic production aims at more holistic production management systems for crops and livestock, emphasizing on-farm management practices over off-farm inputs. This involves avoiding, or largely reducing, the use of synthetic chemicals such as inorganic fertilizers, pesticides, medicinal products, replacing them, wherever possible, with cultural, biological and mechanical methods. Organic producers explicitly aim to develop an allegedly healthier, fertile soil by growing and rotating a mixture of crops and using leguminous crops to fix nitrogen from the atmosphere. The production of genetically-modified (GM) crops and their use in animal feed is banned. In the context of European Union (EU) statistics, farming is considered to be organic if it complies with Regulation 834/2007 of 28 June 2007 on organic production and labelling of organic products. The detailed rules for the implementation of this Regulation are laid down in Regulation 889/2008.

  • Organic fertilizers

    Livestock manures, digestates, green manures, compost, sewage sludge, (agro)industrial organic waste.

  • Organic Matter

    Plant and animal residue in the soil in various stages of decomposition.

  • Organic matter loss

    Decline of organic matter content in one or more soil layers when the annual loss of organic matter (e.g. due to oxidation or erosion) is insufficiently compensated for by the annual gain of organic matter, resulting from crop residues, composts and manures.

  • Overland flow

    Excess water leaving a field horizontally across the soil surface because it cannot infiltrate into the soil, eventually ending up in a ditch or stream (= surface runoff).

  • Oxidation

    The addition of oxygen, removal of hydrogen, or the removal of electrons from an element or compound. In the environment, organic matter is oxidized to more stable substances. Oxidation is the opposite of ‘reduction’. Oxidation of organic matter is termed ‘burning’, and that of iron ‘rusting’.


  • Parent material

    The solid or unconsolidated mineral material in or on which soil forms.

  • Ped

    An individual natural soil aggregate, in contrast to a clod caused by disturbance, or a concretion caused by cementation. Described as a range of shapes: platy (laminated), prismatic (vertical axis of aggregates longer than horizontal), columnar (prisms with rounded tops), blocky (angular or subangular) and granular.

  • Pedon

    The smallest volume that can be called “a soil.” A pedon is three dimensional and large enough to permit study of all horizons. Its area ranges from about 1 to 10 m2, depending on the variability of the soil.

  • Percolation

    The movement of water through the soil.

  • Permeability

    The quality of the soil that enables water to move downward through the profile. Permeability is measured as the distance per unit time that water moves downward through the saturated soil.

    Terms describing permeability are:
    Very slow: 0.15 cm/hr
    Slow: 0.15-0.5 cm/hr
    Moderately slow 0.5-1.5 cm/hr
    Moderate 1.5-5 cm/hr
    Moderately rapid 5.00-15.00 cm/hr
    Rapid 15-50 cm/hr
    Very rapid >50 cm/hr

  • Pesticides

    Synthetic biocide directed at destroying insects, nematodes, molluscs, mammals, plants, fungi or bacteria.

  • pH

    Measure of acidity, measured from 1 (acid) through 7 (neutral) to 14 (alkaline) expressed on a logarithmic scale. Most soils have a pH 3 to 9.

  • Phosphorous (P)

    P2O5      P x 2.29 = P2O5

  • Plastic mulch

    Plastic sheet covering the soil surface to increase the temperature, reduce evaporation or suppress weeds.

  • Pores

    The space in-between particles or aggregates of soil that can become filled with air or water.

  • Porosity

    Volume of water and air that can be held in a soil; ratio of the volume of voids to the total volume of the soil.

  • Potash (K)

    K2O K x 1,20 = K2O

  • Precipitation

    Water reaching the ground from rainfall, snow and hail.

    Nr Environmental Zone Main locations and characteristics
    1 Alpine North (ALN) Scandinavian mountains
    2 Alpine South (ALS) The high mountains of central and southern Europe
    3 Atlantic North (ATN) NW Europe; under influence of the Atlantic ocean and the North sea
    4 Atlantic Central (ATC)  Western Europe, moderate climate
    5 Boreal (BOR)  The lowlands of Scandinavia
    6 Continental (CON)  Central Europe; warm summers and cold winters
    7 Lusitanean (LUS)  The southern Atlantic area; warm summers and mild winters
    8 Mediterranean North (MDN)  Mediterranean north, with Cork Oak, fruit plantations and Olive groves
    9 Mediterranean Mountains (MDM) Mediterranean mountains, influenced by Mediterranean and mountains
    10 Mediterranean South (MDS)  Typical Mediterranean climate; mild winter and hot, dry summers
    11 Nemoral (NEM)  Southern Scandinavia, Baltic states and Belarus
    12 Pannonian (PAN)  Part of Europe with steppes; cold winters and dry hot summers.
    13 Anatolian (ANA)  The steppes of Turkey, a Mediterranean environment with steppes
  • Preferential flow

    Water flow through macro-pores (e.g., cracks, root channels) in the unsaturated/ vadose zone.

  • Profile

    A column of soil extending through all its horizons and into the parent material and large enough to be used to characterise the soil condition at a particular place.

  • Proxy

    A measure linking information from an indicator to a non-concrete (immaterial) end-point (‘soil function’ in the case of LANDMARK). However, a proxy only contributes to a soil function and cannot be held responsible to full quantification (see proxy indicator system).

  • Proxy indicator system

    A combined set of indicators, weighting factors and algorithms for quantification of a soil function based on the quantification of an agreed set of attributes. A proxy indicator system aims at the assemblage of a wide-ranging set of information from indicators (in fact: all required proxies) and provides a quantification protocol of a specific soil function, being as such a compromise between ease of measurement / data availability, whilst providing sufficient, if minimal, information on the attribute (set). Different proxy indicator systems may arise for one soil function, depending on requirements for a) specific spatial/temporal scale, b) agricultural objective, soil texture and climate conditions, and c) the required performance (reduction of uncertainty) and available budgets to harness the proxy indicator system with reliable data and models. It is the objective of LANDMARK to produce proxy indicator systems which are at least partially overlapping (see ‘nestedness’).


  • R horizon

    Hard, consolidated bedrock beneath the soil. The bedrock commonly underlies a C horizon but can be directly below an A or a B horizon.

  • Reduced tillage

    A tillage without inversion at a reduced depth (about 30% crop residues remaining on the surface), with specific machines (often with grubber/cultivator), more than once a year.

  • Reduction

    The addition of hydrogen, removal of oxygen, or the addition of electrons to an element or compound. Under anaerobic conditions (where there is no dissolved oxygen present) such as in ‘gley’ soils, sulphur compounds are reduced to odour-producing hydrogen sulphide (H2S) and other compounds. Reduction is the opposite of oxidation.

  • Relay intercrop

    see Intercrop

  • Relief

    The elevations or inequalities of a land surface, considered collectively.

  • Residue

    Any organic product generated during the production, processing or consumption of crops, ranging from roots, stubbles, straw and leaves, to industrial and urban ‘wastes’.

  • Resilience

    The ability of an ecosystem to maintain diversity, integrity and ecological processes following disturbance (i.e. by returning to its initial state after stress).

  • Resistance

    The ability of an ecosystem to withstand a stress or perturbation without adverse changes to its structure or function, thereby maintaining an equilibrium state.

  • Root zone

    The part of the soil that can be penetrated by plant roots.

  • Runoff

    The precipitation discharged into stream channels from an area. The water that flows off the surface of the land without sinking into the soil is called surface runoff. Water that enters the soil before reaching surface streams is called groundwater runoff or seepage flow from groundwater.


  • S x E x M

    Expression used to indicate that there are intricate interactions between soil properties i.e. diagnostic features (intrinsic and dynamic ones), environment (climate, weather, slope, etc.) and management (the analogue from crop production is G (genotype) x E x M), acknowledging that soil functions are never uniquely determined by just one of these three factors.

  • Salinization

    Accumulation of soluble salts (more soluble than gypsum) in the upper soil layers (saline soil = soil containing enough soluble salts to negatively affect most crop plants, commonly 4000 μS m-1).

  • Sand

    Soil particles being 0.06 (0.051) -2.0 mm in diameter OR a soil textural class with 65% or more sand and less than 8% clay.

  • Saturated zone

    Subsurface area below unsaturated/ vadose zone that is permanently water-saturated.

  • Seepage

    The movement of water through the soil.

  • Silt

    Soil particles being 0.002-0.06 (0.051) mm.

  • Slacking

    Sealing of the (upper few cm) soil by the destruction of soil aggregates after wetting, causing a fine crust to occur, which reduces permeability of the soil and hamper seedling emergence.

  • Slope

    The inclination of the land surface from the horizontal. Percentage of slope is the vertical distance divided by horizontal distance, multiplied by 100. Thus, a slope of 20 percent is a drop of 20 m in 100 m of horizontal distance.

  • Slurry

    A liquid mixture of livestock urine and faeces, with or without some water and or bedding material.

  • Sodification

    Increase in the amount of exchangeable Na of a soil (sodic soil = soil containing enough Na to negatively affect most crop plants by changing the physical soil properties).

  • Soil

    A combination of four constituents: mineral material (sand, silt, clay and rock particles), organic material, air and water, forming a natural, three-dimensional body at the earth’s surface. It is capable of supporting plant growth and has properties resulting from the integrated effect of climate and living matter acting on parent material, as conditioned by relief over periods of time.

  • Soil compaction

    Changing the nature of the soil such that there is a decrease in the volume of voids between soil particles or aggregates; it is manifested as an increase in bulk density and a severely compacted soil can become significantly less permeable and less aerated. Manmade compaction is caused by poaching (trampling of animal hooves repeatedly) or by the passage of heavy machinery. Other typical examples are “plough pans” (plough sole or traffic pan) which can be formed due to tillage and which can negatively affect root development and drainage.

  • Soil contamination

    Accumulation of nutrients, metals or organic compounds leading to a reduction of the capacity of soils to deliver soil functions. Contamination may have a direct toxic effect on the plants, animals or humans living in, on, or from that soil, or have an indirect toxic effect due to accumulation in the whole trophic chain.

  • Soil cover

    The extent to which a soil is covered (in space and/or time) by a vegetation, including crops, or dead crop residues on the surface of the soil, directed at reducing soil erosion and the loss of particulate pollutants (i.e. those attached to soil) including nutrients, plant protection products and fecal microbes. Measures directed at increasing the soil cover may also increase soil organic matter.

  • Soil depth

    Depth of soil profile from the top to parent material or bedrock or to the layer below root penetration is not (or no longer) possible. It differs significantly for different soil types. It is one of basic criterions used in soil classification. Soils can be very shallow (less than 25 cm), shallow (25 cm-50 cm), moderately deep (50 cm-90 cm), deep (90cm-150 cm) and very deep (more than 150 cm).

  • Soil fertility

    The ability of the soil to supply essential plant nutrients and soil water in adequate amounts and proportions for plant growth and reproduction in the absence of toxic substances which may inhibit plant growth.

  • Soil functions

    Soil based ecosystem services: an overarching concept referring to one (out of five, following Schulte et al., 2014) elemental aspect of the soil system that contributes to the generation of goods and services.

    The contemporary principal soil functions pertaining to agricultural land use (U110) and forestry (U120) include: (1) primary productivity, (2) water purification and regulation, (3) carbon sequestration and other aspects of climate regulation, (4) provision of a habitat for functional and intrinsic biodiversity and (5) nutrient cycling and provision, with:

    SFi,j = F (soil features, environmental variables, management options)

    where SFi,j is soil function i for agricultural objective j.


    More info here

  • Soil productivity

    The capacity of a soil to produce plant biomass for human use, providing food, feed, fibre and fuel within natural or managed ecosystem boundaries.

  • Soil quality

    The degree to which a soil can perform its soil functions. A soil with ‘high soil quality’ can deliver the desired functions to meet demands, whereas a soil with ‘low soil quality’ delivers functions at sub-optimal rates.

  • Soil sealing

    The process of covering of a soil by buildings, or types of artificial material which may be very slowly permeable to water (e.g. asphalt or concrete). Soil sealing can cause rapid overland flow after precipitation where water cannot soak away leading to potential flooding. A soil is unable to function effectively when sealed.

  • Solum

    Topsoil and subsoil layers that have undergone the same soil forming conditions. The base of the solum (plural, sola) is the relatively unweathered parent material. Solum and soils are not synonymous. Some soils include layers that are not affected by soil formation.

  • Specific Heat Capacity

    The amount of heat which is required in order to increase its temperature. Measured in ‘joules per kilogram per kelvin degree’, or J/kg/oK , it is specifically the amount of heat energy in joules needed to increase the temperature of one kilogram of the substance by one Kelvin degree.

  • Sprinkler irrigation

    Application of water to the field by a sprinkler system which mimics a high intensity rainfall, can be mobile of fixed.

  • Stones

    Soil particles more than 2 mm in diameter.

  • Strip cropping

    Growing crops in a systematic arrangement of strips or bands which provide vegetative barriers to wind and water erosion.

  • Strip tillage

    The process in which only a narrow strip of land needed for the crop row is tilled.

  • Structure

    The aggregation of primary soil particles into units separated from each other by surfaces of weakness, ‘architecture’ of soil – how it is constructed and made up.

  • Subsoil

    Technically, soil horizons below plough depth; usually B horizons.

  • Surface irrigation

    Application of water to the field that flows over the land surface or in narrow channels (e.g.furrow or basin sprinkler).

  • Surface water

    Water bodies flowing over or resting on the surface of a land mass, natural waterway (rivers, streams, brooks and lakes) or artificial waterway, including irrigation, industrial and navigation canals, drainage systems and artificial reservoirs.

  • Sustainable intensification

    Policies and practices directed at increasing the productivity (‘yield per unit area’) without increasing the environmental impact (‘impact per unit area and produce’) (Garnett et al., 2013).


  • Texture

    The relative proportions of sand, silt, and clay particles in a mass of soil. Texture can be coarse (sand particles predominate), medium (equal parts of sand, silt and clay), or fine (clay particles predominate). The basic textural classes, in order of increasing proportion of fine particles, are; sand, loamy sand, sandy loam, loam, silt loam, silt, sandy clay loam, clay loam, silty clay loam, sandy clay, silty clay, and clay. The sand, loamy sand, and sandy loam classes may be further divided by specifying “coarse,” “fine”, or “very fine’.

    See texture triangle.

  • Texture triangle

    Diagram allotting names to soils with specific portions of sand, silt and clay (, consult Figure:


  • Tillage

    The mechanical cultivation of a soil profile for any purpose. Tillage can be performed to accomplish a number of tasks including: breaking compactions, incorporation of crop residues, manures, fertilizers or weeds, seedbed preparation, weed control.

  • Topsoil

    The surface soil horizon (A) which is modified when cultivated, and designated Ap.

  • Trafficability

    The capacity of soil to carry machinery without significant damage to the soil or the vegetation growing on it.

  • Transpiration

    The process whereby plants lose water by evaporation of liquid water at the surface of the stomatal cells, the water vapour diffusing out through the leaf via the stomata openings.



  • Vadose zone

    The aerated region of soil above the groundwater table. The unsaturated zone is characterized by a downward movement of leachate.


  • Water deficit

    Amount of water (mm) needed to return moisture conditions of a soil back to field capacity.

  • Water holding capacity

    The capacity of soils to hold water that is available for use by most plants. It is commonly defined as the difference between the amount of soil water at field moisture capacity and the amount at wilting point. It is commonly expressed as mm of water per m of soil.

  • Water purification

    The capacity of a soil to remove harmful compounds from the water that it holds.

  • Water regulation

    The capacity of a soil to receive, store and conduct water for subsequent use and the reduction of consequences of prolonged droughts and risks of flooding and erosion .

  • Water table

    The upper surface of groundwater or that level in the ground where the water is at atmospheric pressure. Different horizons can be recognized, such as the highest and lowest average height of the groundwater level in summer or winter.

  • Weathering

    The process by which materials in rocks or other deposits are broken down into smaller parts and ultimately their constituents. An example is ‘freeze thaw’ expansion and cracking. There are physical, chemical and biological weathering processes.

  • Wilting point

    Soil moisture content where the rate of absorption of water by plant roots is too slow to maintain plant turgidity and permanent wilting occurs. The average moisture tension at the outside surface of the moisture film around soil particles when permanent wilting occurs is 1500 kPa.


  • Zero tillage

    An agronomic practice in Conservation Agriculture (CA) for annual crops, and is defined as a way to farm without disturbing the soil through tillage. Zero tillage must leave at least 30% of area covered by plant residues right after crop establishment, and crops are sown using machinery which is able to place seeds through plant residues from previous crops. The agronomic practice that best characterizes CA for annual crops is Zero Tillage, which has the highest degree of soil conservation in annual crops, since the mechanical tillage of the ground is completely suppressed. Also, in arid climates it enhance water retention in soils through decreasing evaporation losses from the soil surface which is usually enhanced by tillage involving soil invert.