Edaphology (from Greek , ''edaphos'' 'ground' + , ''

-logia ''-logy'' is a suffix in the English language, used with words originally adapted from Ancient Greek ending in ('). The earliest English examples were anglicizations of the French '' -logie'', which was in turn inherited from the Latin '' -lo ...

'') is concerned with the influence of

soil Soil, also commonly referred to as earth, is a mixture of organic matter, minerals, gases, water, and organisms that together support the life of plants and soil organisms. Some scientific definitions distinguish dirt from ''soil'' by re ...

s on living beings, particularly plants. It is one of two main divisions of

soil science Soil science is the study of soil as a natural resource on the surface of the Earth including soil formation, soil classification, classification and Soil survey, mapping; Soil physics, physical, Soil chemistry, chemical, Soil biology, biologica ...

, the other being pedology. Edaphology includes the study of how soil influences humankind's use of land for plant growth as well as people's overall use of the land. General subfields within edaphology are

agricultural soil science Agricultural soil science is a branch of soil science that deals with the study of edaphology, edaphic conditions as they relate to the food production, production of food and fiber. In this context, it is also a constituent of the field of agro ...

(known by the term agrology in some regions) and environmental soil science. Pedology deals with pedogenesis, soil morphology, and soil classification.

History

The history of edaphology is not simple, as the two main alternative terms for soil science—pedology and edaphology—were initially poorly distinguished. Friedrich Albert Fallou originally conceived pedology in the 19th century as a fundamental science separate from the applied science of agrology, a predecessor term for edaphology, a distinction retained in the current understanding of edaphology. During the 20th century, the term edaphology was "driven out of edology-centricsoil science" but remained in use to address edaphic problems in other disciplines. In the case of Russian soil scientists, edaphology was used as an equivalent term to pedology, and in Spain, soil scientists adopted edaphology in preference to the term pedology. In the 21st century, edaphology is recognized by soil scientists as a branch of soil science necessary and complementary to the pedology branch.

Xenophon Xenophon of Athens (; ; 355/354 BC) was a Greek military leader, philosopher, and historian. At the age of 30, he was elected as one of the leaders of the retreating Ancient Greek mercenaries, Greek mercenaries, the Ten Thousand, who had been ...

(431–355 BC), and Cato (234–149 BC), were early edaphologists. Xenophon noted the beneficial effect of turning a cover crop into the earth. Cato wrote De Agri Cultura ("On Farming"), which recommended

tillage Tillage is the agriculture, agricultural preparation of soil by mechanical wikt:agitation#Noun, agitation of various types, such as digging, stirring, and overturning. Examples of manual labour, human-powered tilling methods using hand tools inc ...

crop rotation Crop rotation is the practice of growing a series of different types of crops in the same area across a sequence of growing seasons. This practice reduces the reliance of crops on one set of nutrients, pest and weed pressure, along with the pro ...

, and the use of legumes in the rotation to build soil nitrogen. He also devised the first soil capability classification for specific crops.

Jan Baptist van Helmont Jan Baptist van Helmont ( , ; 12 January 1580 – 30 December 1644) was a chemist, physiologist, and physician from Brussels. He worked during the years just after Paracelsus and the rise of iatrochemistry, and is sometimes considered to be ...

(1577–1644) performed a famous experiment, growing a willow tree in a pot of soil and supplying only rainwater for five years. The weight gained by the tree was greater than the weight loss of the soil. He concluded that the willow was made of water. Although only partly correct, his experiment reignited interest in edaphology.

Areas of study

Agricultural soil science

Agricultural soil science is the application of soil chemistry, physics, and biology dealing with the production of crops. In terms of

soil chemistry Soil chemistry is the study of the Chemistry, chemical characteristics of soil. Soil chemistry is affected by mineral composition, organic matter and Environment (biophysical), environmental factors. In the early 1870s a consulting chemist to the R ...

, it places particular emphasis on plant nutrients of importance to

farming Agriculture encompasses crop and livestock production, aquaculture, and forestry for food and non-food products. Agriculture was a key factor in the rise of sedentary human civilization, whereby farming of domesticated species created ...

and

horticulture Horticulture (from ) is the art and science of growing fruits, vegetables, flowers, trees, shrubs and ornamental plants. Horticulture is commonly associated with the more professional and technical aspects of plant cultivation on a smaller and mo ...

, especially with regard to soil fertility and

fertilizer A fertilizer or fertiliser is any material of natural or synthetic origin that is applied to soil or to plant tissues to supply plant nutrients. Fertilizers may be distinct from liming materials or other non-nutrient soil amendments. Man ...

components. Physical edaphology is strongly associated with crop

irrigation Irrigation (also referred to as watering of plants) is the practice of applying controlled amounts of water to land to help grow crops, landscape plants, and lawns. Irrigation has been a key aspect of agriculture for over 5,000 years and has bee ...

and

drainage Drainage is the natural or artificial removal of a surface's water and sub-surface water from an area with excess water. The internal drainage of most agricultural soils can prevent severe waterlogging (anaerobic conditions that harm root gro ...

. Soil husbandry is a strong tradition within agricultural soil science. Beyond preventing

soil erosion Soil erosion is the denudation or wearing away of the Topsoil, upper layer of soil. It is a form of soil degradation. This natural process is caused by the dynamic activity of erosive agents, that is, water, ice (glaciers), snow, Atmosphere of Ea ...

and degradation in cropland, soil husbandry seeks to sustain the agricultural soil resource though the use of soil conditioners and cover crops.

Environmental soil science

Environmental soil science studies our interaction with the

pedosphere The pedosphere () is the Earth's crust, outermost layer of the Earth that is composed of soil and subject to soil formation processes. It exists at the interface of the lithosphere, Atmosphere of Earth, atmosphere, hydrosphere and biosphere. The ...

on beyond crop production. Fundamental and applied aspects of the field address

vadose zone The vadose zone (from the Latin word for "shallow"), also termed the unsaturated zone, is the part of Earth between the land surface and the top of the phreatic zone, the position at which the groundwater (the water in the soil's pores) is at ...

functions, septic drain field site assessment and function, land treatment of

wastewater Wastewater (or waste water) is water generated after the use of freshwater, raw water, drinking water or saline water in a variety of deliberate applications or processes. Another definition of wastewater is "Used water from any combination of do ...

, stormwater,

erosion Erosion is the action of surface processes (such as Surface runoff, water flow or wind) that removes soil, Rock (geology), rock, or dissolved material from one location on the Earth's crust#Crust, Earth's crust and then sediment transport, tran ...

control,

soil contamination Soil contamination, soil pollution, or land pollution as a part of land degradation is caused by the presence of xenobiotic (human-made) chemicals or other alteration in the natural soil environment. It is typically caused by industrial activit ...

with metals and pesticides, remediation of contaminated soils, restoration of

wetlands A wetland is a distinct semi-aquatic ecosystem whose groundcovers are flooded or saturated in water, either permanently, for years or decades, or only seasonally. Flooding results in oxygen-poor ( anoxic) processes taking place, especially ...

soil degradation Soil retrogression and degradation are two regressive evolution processes associated with the loss of equilibrium of a soil health, stable soil. Retrogression is primarily due to soil erosion and corresponds to a phenomenon where succession revert ...

, and environmental nutrient management. It also studies soil in the context of

land-use planning Land use planning or ''Land-use regulation'' is the process of regulating the use of land by a central authority. Usually, this is done to promote more desirable social and environmental outcomes as well as a more efficient use of resources. ...

global warming Present-day climate change includes both global warming—the ongoing increase in global average temperature—and its wider effects on Earth's climate system. Climate change in a broader sense also includes previous long-term changes ...

, and

acid rain Acid rain is rain or any other form of Precipitation (meteorology), precipitation that is unusually acidic, meaning that it has elevated levels of hydrogen ions (low pH). Most water, including drinking water, has a neutral pH that exists b ...

Industrialization and edaphology

Industrialization Industrialisation (British English, UK) American and British English spelling differences, or industrialization (American English, US) is the period of social and economic change that transforms a human group from an agrarian society into an i ...

has impacted the way that

interacts with

plants Plants are the eukaryotes that form the kingdom Plantae; they are predominantly photosynthetic. This means that they obtain their energy from sunlight, using chloroplasts derived from endosymbiosis with cyanobacteria to produce sugars f ...

in various ways. Increased mechanical production has led to higher amount of heavy metals within soils. These heavy metals have also been found in crops. While, the increased use of synthetic

and

pesticides Pesticides are substances that are used to pest control, control pest (organism), pests. They include herbicides, insecticides, nematicides, fungicides, and many others (see table). The most common of these are herbicides, which account for a ...

has decreased the nutrient availability of soils. Changes in agricultural practices, such as monocropping and tilling, as a result of industrialization have also impacted aspects of edaphology. Monocropping techniques are efficient for harvesting and business strategies but lead to a decrease in

biodiversity Biodiversity is the variability of life, life on Earth. It can be measured on various levels. There is for example genetic variability, species diversity, ecosystem diversity and Phylogenetics, phylogenetic diversity. Diversity is not distribut ...

. Decreased biodiversity is shown to decrease the nutrients available in soils. Furthermore, monocropping leads to an increased dependency on chemical fertilizer. While intensive tilling disturbs the community of microorganism that live with in soil. These microorganisms help maintain soil moisture and air circulation which are critical to plant growth.

Notes

References

European Environment Information and Observation Network (EIONET)
Url last accessed 2006-01-10 * SSS
Soil Science Glossary
Url last accessed 2016-01-10

External links

* {{Physical geography topics Soil science Physical geography