What are plinthic soils?

Plinthosols are soils with ‘plinthite’ – a firm but soft, iron‐rich, red‐mottled clay, made up of a humus‐poor mixture of kaolinite, quartz and other constituents that irreversibly hardens to petroplinthite when exposed to repeated wetting and drying.

What is plinthic?

Plinthite (Gr. plinthos, brick) is an iron-rich, humus-poor mixture of clay with quartz and other highly weathered minerals. It commonly occurs as reddish redox concentrations in a layer that has a polygonal (irregular), platy (lenticular), or reticulate (blocky) pattern.

What is Fragipan soil?

In Soil Taxonomy (Soil Survey Staff, 2010) a fragipan (from the Latin fragilis, meaning “brittle”) is defined as a layer that is 15 cm or more thick, contains a very coarse prismatic, columnar, or blocky structure (or is massive), has a firm or firmer rupture-resistance class (brittle) in more than 60% of its volume.

How is Plinthite formed?

Plinthite formation occurs in conjunction with Btx horizon degradation and in a zone of Fe-accumulation having a firm to very firm consistency. PLINTHITE is an iron-rich, humus-poor mixture of clay with fine quartz.

Which physical properties are taken care of when classifying soil detail them?

Pore size, texture, structure and the presence of impervious layers such as clay pan determines the permeability of a soil.

What is the meaning of vertisols?

Vertisols (from Latin verto, “turn”) are clay-rich soils that shrink and swell with changes in moisture content. During dry periods, the soil volume shrinks and deep wide cracks form.

What type of soil is caliche?

Caliche is a whitish-gray or cream-colored soil layer that has been cemented by carbonates of calcium and magnesium. Caliche may occur as a soft, thin soil horizon (layer); a hard, thick bed; or a layer exposed to the surface by erosion (SSSA, 2001).

What makes a soil hydric?

The definition of a hydric soil is a soil that formed under conditions of saturation, flooding or ponding long enough during the growing season to develop anaerobic conditions in the upper part.

What is soil texture?

Soil texture (such as loam, sandy loam or clay) refers to the proportion of sand, silt and clay sized particles that make up the mineral fraction of the soil. For example, light soil refers to a soil high in sand relative to clay, while heavy soils are made up largely of clay. the amount of water the soil can hold.

What are the 5 properties of soil?

All soils contain mineral particles, organic matter, water and air. The combinations of these determine the soil’s properties – its texture, structure, porosity, chemistry and colour.

What are the 6 types of soil?

There are six main types of soil: loamy, chalky, peaty, silty, sandy, and clay. Each of these types has different properties that you need to understand to get the most from your garden.

What kind of soil is a plinthite made of?

Plinthite is a redoximorphic feature in highly weathered soil. The product of pedogenesis, it commonly occurs as dark red redox concretions that usually form platy, polygonal, or reticulate patterns.

What makes a plinthite hard in a field?

Plinthite is firm or very firm when the soil moisture content is near field capacity and hard when the moisture content is below the permanent wilting point. Plinthite concretions are coherent enough to be separated readily from the surrounding soil. Plinthite commonly occurs within and above reticulately mottled horizons.

Where does the iron in plinthite come from?

Generally, plinthite forms in a soil horizon that is saturated with water for some time during the year. Initially, iron is normally segregated in the form of soft, more or less clayey, red or dark red redox concretions.

How are plinthic soils used in palaeoenvironmental reconstruction?

Fossil plinthic soils are potential proxies for palaeoenvironmental reconstruction. Measures used in the management of plinthic soils include mechanically breaking the hardpans and the use of organic and inorganic amendments to modify the structure and chemistry of the soils.