* Unified Soil Classification System, a soil classification system used in engineering and geology

* Soil Science – study of soil as a natural resource on the surface of the earth including soil formation, classification and mapping ; physical, chemical, biological, and fertility properties of soils ; and these properties in relation to the use and management of soils.

* Soil classification systems cannot be based entirely on perceptions of genesis, however, because genetic processes are seldom observed and because pedogenic processes change over time.

Soil science is the study of soil as a natural resource on the surface of the earth including soil formation, classification and mapping ; physical, chemical, biological, and fertility properties of soils ; and these properties in relation to the use and management of soils.

As of 2006, the World Reference Base for Soil Resources, via its Land & Water Development division, is the pre-eminent soil classification system.

** Soil classification

The Food and Agriculture Organization of the United Nations ( FAO ) developed a supra-national classification, also called World Soil Classification, which offers useful generalizations about soils pedogenesis in relation to the interactions with the main soil-forming factors.

Originally developed as a legend to the Soil Map of the World, the classification was applied by United Nations sponsored projects.

* Soil classification systems

* Soil classification

* Soil classification

USDA Soil Taxonomy developed by United States Department of Agriculture and the National Cooperative Soil Survey provides an elaborate classification of soil types according to several parameters ( most commonly their properties ) and in several levels: Order, Suborder, Great Group, Subgroup, Family, and Series.

* Soil classification

* Soil classification

C1. 4 Soil classification.

Soil classification deals with the systematic categorization of soils based on distinguishing characteristics as well as criteria that dictate choices in use.

Soil classification is a dynamic subject, from the structure of the system itself, to the definitions of classes, and finally in the application in the field.

The most common engineering classification system for soils in North America is the Unified Soil Classification System ( USCS ).

Other engineering soil classification systems in the States include the AASHTO Soil Classification System and the Modified Burmister ( See biographical sketch of Prof. Donald Burmister ).

Soil texture triangle showing the USDA classification system based on grain size

Natural system approaches to soil classification, such as the French Soil Reference System ( Référentiel pédologique français ) are based on presumed soil genesis.

Soil taxonomy based soil map units are additionally sorted into classes based on technical classification systems.

* Soil texture classification

Soil type, drainage, or degree of slope can make the difference between good crops and poor ones.

Soil biology and chemistry can be seriously damaged by acid rain.

Soil chemistry can be dramatically changed when base cations, such as calcium and magnesium, are leached by acid rain thereby affecting sensitive species, such as sugar maple ( Acer saccharum ).

Soil moisture can be measured in various ways ; by capacitance probe, time domain reflectometer or Tensiometer.

The Climate, Soil, and Sea provide everything that can be expected from them.

Soil fertility can sometimes be mitigated by applying the appropriate lime and organic fertilizers.

According to the Soil Association, the total copper that can be applied to organic land is 6 kg / ha / year.

Soil forms a structure filled with pore spaces and can be thought of as a mixture of solids, water, and air ( gas ).

Soil factors such as density, depth, chemistry, pH, temperature and moisture greatly affect the type of plants that can grow in a given location.

Soil building and pest population management benefits can be further utilized with different complexities of crop rotation.

Soil salinity can be reduced by leaching soluble salts out of soil with excess irrigation water.

From the FAO / UNESCO Soil Map of the World the following salinised areas can be derived.

Soil of the Town is generally clay loam and somewhat difficult to cultivate, but heavy crops of wheat can be grown on the land, thus giving the Town its name-Wheatfield.

* Soil analysis, such as determining pH, can help to confirm the presence of physiological disorders.

Soil steaming can be used as an ecological alternative to chemicals for soil sterilization.

Soil failure can also occur due to earthquake-induced landslides in steep terrain.

Much of this is oriented towards the use of herbicides, the majority of which may not be acceptable to the organic producer ( apart from non-synthetic substances like sulphur, which in some circumstances are accepted within Soil Association standards ) but in most cases there are manual techniques that can be used such as digging out the roots, mulching out or carefully timed cutting before seeds are able to spread.

Soil that are high in calcium minerals, for example, can be given green manure to generate a higher phosphate content in the soil, which in turn acts as a fertilizer.

Soil erosion is a process that can irreparably reduce the productive capacity of an agroecosystem.

Soil failure can occur on a slope, a slope failure or landslide, or in a flat area due to liquefaction of water-saturated sand and / or mud.

In May 2005, McKeith was given the Best Organic Businesses 2005 Consumer Education Award by the Soil Association, a British charity promoting organic food, in recognition of her work in " tackling obesity, championing healthier eating and promoting the contribution that organic fruit, vegetables and other products can make to sound nutrition.

A number of Borsodi's texts can be found in the Social Criticism section of the Soil and Health Online Library.

Soil and sand carried through a culvert can wear away the galvanizing of a steel culvert, allowing it to corrode and eventually collapse, disrupting the road or railway above it.

Soil in good tilth is loamy, nutrient-rich soil that can also be said to be friable because optimal soil has a mixture of sand, clay and organic matter that prevents severe compaction.