Substrate is the earthy material that forms or collects at the bottom of an aquatic habitat. It is made of
sediments
Sediment is a solid material that is transported to a new location where it is deposited. It occurs naturally and, through the processes of weathering and erosion, is broken down and subsequently sediment transport, transported by the action of ...
that may consist of:
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Silt
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 (chemistry), suspension with water. Silt usually ...
– A loose, granular material with mineral particles 0.5 mm or less in diameter.
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Clay
Clay is a type of fine-grained natural soil material containing clay minerals (hydrous aluminium phyllosilicates, e.g. kaolinite, ). Most pure clay minerals are white or light-coloured, but natural clays show a variety of colours from impuriti ...
– A smooth, fine-grained material made of fine particles of
hydrous aluminium
Aluminium (or aluminum in North American English) is a chemical element; it has chemical symbol, symbol Al and atomic number 13. It has a density lower than that of other common metals, about one-third that of steel. Aluminium has ...
phyllosilicate minerals (such as
kaolinite
Kaolinite ( ; also called kaolin) is a clay mineral, with the chemical composition Al2 Si2 O5( OH)4. It is a layered silicate mineral, with one tetrahedral sheet of silica () linked through oxygen atoms to one octahedral sheet of alumina () ...
).
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Mud
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 cal ...
– A mixture of water with silt, clay, or
loam
Loam (in geology and soil science) is soil composed mostly of sand (particle size > ), silt (particle size > ), and a smaller amount of clay (particle size < ). By weight, its mineral composition is about 40–40–20% concentration of sand–si ...
.
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Sand
Sand is a granular material composed of finely divided mineral particles. Sand has various compositions but is usually defined by its grain size. Sand grains are smaller than gravel and coarser than silt. Sand can also refer to a textural ...
– Mineral particles between 0.06 and 2 mm in diameter.
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Granule – Between 2 and 4 mm in diameter.
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Pebble
A pebble is a clastic rocks, clast of rock (geology), rock with a grain size, particle size of based on the Particle size (grain size), Udden-Wentworth scale of sedimentology. Pebbles are generally considered larger than Granule (geology), gra ...
– Between 4 – 64 mm in diameter.
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Cobble – between 6.4 and 25.6 cm in diameter
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Boulder
In geology, a boulder (or rarely bowlder) is a rock fragment with size greater than in diameter. Smaller pieces are called cobbles and pebbles. While a boulder may be small enough to move or roll manually, others are extremely massive. In ...
– more than 25.6 cm in diameter.
*Other, assorted organic matter,
detritus
In biology, detritus ( or ) is organic matter made up of the decomposition, decomposing remains of organisms and plants, and also of feces. Detritus usually hosts communities of microorganisms that colonize and decomposition, decompose (Reminera ...
.
Stream substrate can affect the life found within the stream habitat. Muddy streams generally have more sediment in the water, reducing clarity. Clarity is one guide to stream health.
Marine substrate can be classified geologically as well. See Green et al., 1999 for a reference.
Mollusks and clams that live in areas with substrate, and need them to survive, use their silky byssal threads to cling to it. See Cteniodes Ales for reference.
See also
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Grain size
Grain size (or particle size) is the diameter of individual grains of sediment, or the lithified particles in clastic rocks. The term may also be applied to other granular materials. This is different from the crystallite size, which ...
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Substrate (biology)
In biology, a substrate is the surface on which an organism (such as a plant, fungus, or animal) lives. A substrate can include biotic or abiotic materials and animals. For example, encrusting algae that lives on a rock (its substrate) can be it ...
References
Bibliography
*Gordon, McMahon, Finlayson, Gippel and Nathan. "Substrate". Stream Hydrology: An Introduction for Ecologists. 2nd Ed. John Wiley and Sons. 2004. p
13& 14.
*Baker, Ffolliott, DeBano and Neary (eds). "Stream Substrate". Riparian Areas of the Southwestern United States: Hydrology, Ecology, and Management. Lewis Publishers. 2004. Taylor and Francis e-Library. 2005. p
285& 286.
*"Stream Substrate Particle Size". Eldorado and Tahoe National Forests (N.F.), Range Standards & Guidelines to Amend the Land & Resource Management Plans of the Eldorado and Tahoe National Forests. Draft Environmental Impact Statement. July 1999. Pag
A-6
{{DEFAULTSORT:Substrate (Marine Biology)
Aquatic ecology
Marine biology