Soil

thumb|upright=1.25|Surface-water-Gley soil|gley developed in [[glacial till in Northern Ireland]]

thumb|upright=1.35|A pair of muddy Wellington boot|Wellington boots thumb|Gamo mud volcano in Tokamachi, Japan Mud (, or Middle Dutch) is loam, silt or clay mixed with water. Mud is usually formed after rainfall or near water sources. Ancient mud deposits hardened over geological time to form sedimentary rock such as shale or mudstone (generally called lutites). When geological deposits of mud are formed in estuaries, the resultant layers are termed bay muds. Mud has also been used for centuries as a construction resource for mostly houses and also used as a binder. An Old English word for it

thumb|upright=1.3|Community-level composting in a rural area in Germany

thumb|upright=1.35|A natural arch produced by erosion of differentially weathered rock in Jebel Kharaz ([[Jordan)]]

thumb|Windrow of windblown silt, Northwest Territories, Canada|right Silt is granular material of a size between sand and clay and composed mostly of broken grains of quartz. Silt may occur as a soil (often mixed with sand or clay) or as sediment mixed in suspension with water. Silt usually has a floury feel when dry, and lacks plasticity when wet. Silt can also be felt by the tongue as granular when placed on the front teeth (even when mixed with clay particles).

thumb|Soil types by clay, silt and sand composition as used by the United States Department of Agriculture

thumb|Soil and water being splashed by a raindrop

actions to limit climate change in order to reduce the risks of global warming

thumb|Ibyuk pingo near Tuktoyaktuk, northern Canada thumb|View from top of a pingo towards another, within a partly drained lake, the Arctic Ocean in the background (near Tuktoyaktuk). July 20, 1975.

type of coastal ecosystem, land outside the dikes that is not flooded with seawater with average high tide

Geosmin ( ) is an irregular sesquiterpenoid with a distinct earthy or musty odor, which most people can easily smell. The geosmin odor detection threshold in humans is very low, ranging from 0.006 to 0.01 micrograms per liter in water. Geosmin, along with 2-methylisoborneol, are the major biological causes of taste and odor outbreaks in drinking water worldwide and in farmed fish. Geosmin is also responsible for the earthy taste of beetroots and a contributor to the strong scent, known as petrichor, that occurs when rain falls after a spell of dry weather or when soil is disturbed.

thumb|upright=1.3|Avaste Nature Reserve|Avaste Fen, Estonia. Sedges dominate the landscape. Woody shrubs and trees are sparse. thumb|upright=1.3|Wicken Fen, England. Grasses in the foreground are typical of a fen.

soft diatomite variety

type of pollution caused by agriculture

thumb|300px|Residents and volunteers work to fill sandbags during the Great Flood of 1993|Mississippi and Missouri river floods of 1993. thumb|300px|Members of the Georgia National Guard filling sandbags in preparation for floods.

arrangement of a soil's particles and pore spaces

preservation of soil nutrients

In soil science, agriculture and gardening, hardpan or soil pan is a dense layer of soil, usually found below the uppermost topsoil layer. There are different types of hardpan, all sharing the general characteristic of being a distinct soil layer that is largely impervious to water. Some hardpans are formed by deposits in the soil that fuse and bind the soil particles. These deposits can range from dissolved silica to matrices formed from iron oxides and calcium carbonate. Others are man-made, such as hardpan formed by compaction from repeated plowing, particularly with moldboard plows, or by

thumb|Surface runoff of topsoil from a field in Iowa during a rainstorm

2015 UN theme year

medium in which to grow plants

finely grained regolith on the Moon

thumb|right|A downslope view of part of the erosion|eroding rill network from [[County Tyrone, Northern Ireland. See below for a close-up view of a single rill]] In hillslope geomorphology, a rill is a shallow channel (no more than a few inches/centimeters deep) cut into soil by the erosive action of flowing surface water. Similar but smaller incised channels are known as microrills; larger incised channels are known as gullies.

natural occurence

fermentation process for food waste and similar organic matter

loss of soil nutrients in agriculture

water content of the soil

Imogolite is an aluminium silicate clay mineral with the chemical formula . It occurs in soils formed from volcanic ash and was first described in 1962 for an occurrence in Uemura, Kumamoto prefecture, Kyushu Region, Japan. Its name originates from the Japanese word , which refers to the brownish yellow soil derived from volcanic ash. It occurs together with allophane, quartz, cristobalite, gibbsite, vermiculite and limonite.

short distance movement of coherent earth down a slope

ecosystem associated with a thin basic soil

soil -exchange of gases between plant roots and the atmosphere

A bioeffector is a viable microorganism or active natural compound which directly or indirectly affects plant performance (biofertilizer), and thus has the potential to reduce fertilizer and pesticide use in crop production.

fine-grained, silt-sized particles of rock

layer of topsoil above permafrost

method of farming which involves cultivating a field partitioned into long, narrow strips which are alternated in a crop rotation system

Bioclogging or biological clogging refers to the blockage of pore space in soil by microbial biomass, including active cells and their byproducts such as extracellular polymeric substance (EPS). The microbial biomass obstructs pore spaces, creating an impermeable layer in the soil and significantly reducing water infiltration rates.

Lessivage, or argilluviation, refers to the movement of fine clay minerals from the upper part of a soil to the lower part of a soil, via the downward movement of water through the soil matrix. Lessivage is the primary mechanism in the formation of the diagnostic, clay-enriched argic, or Bt horizon (Canadian System of Soil Classification) of Luvisolic soils.

hydrological property of soil

humus form

Duricrust is a hard layer on or near the surface of soil. Duricrusts can range in thickness from a few millimeters or centimeters to several meters.

a state of soil, meeting ecosystem functions

instrument

very fine powder commonly found in deserts

thumb|upright=1.12|Silcrete (siliceous paleosol) in the Waddens Cove Formation (formed during the Pennsylvanian), Sydney Basin, [[Nova Scotia]] Silcrete is an indurated (resists crumbling or powdering) soil duricrust formed when surface soil, sand, and gravel are cemented by dissolved silica. The formation of silcrete is similar to that of calcrete, formed by calcium carbonate, and ferricrete, formed by iron oxide. It is a hard and resistant material, and though different in origin and nature, appears similar to quartzite. As a duricrust, there is potential for preservation of root structures

controlling the problem of soil salinity

confinement system used in construction and geotechnical engineering

geological feature in Thurston County, Washington state, United States of America

degree of variation of life forms associated with soil

solid carbon stored in global soils