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Sand: definition and meaning

Sand: definition and meaning


SAND

Sand is an incoherent sedimentary rock that derives from the disintegration of pre-existing rocks.
For plant cultivation we basically consider three types of sand:
  • quarry sand: derived from atmospheric decomposition especially of silica rocks. In fact, the sand is composed of 95% silicon oxide (SiO2) and the rest of quartz (not used by plants);
  • river sand: it is the sand that we find on the banks of rivers. This sand, in order to be used, must be sterilized well as it contains numerous nematodes (worms from a few millimeters to a few decimetres, parasites or free-living, which are found in fresh water, marine or damp soil) that would damage the plant;
  • sea ​​sand: it is the sand that we find by the sea. This sand cannot be used as it is for the cultivation of plants as it contains very high concentrations of mineral salts (sodium chloride) which are harmful to the plants unless repeated washing is carried out to desalinate it (operation not easy to carry out in a domestic environment. ).
In plant cultivation the best sand is therefore quarry sand, especially the crystalline one, very light yellow in color formed by very small particles as the coarse one would not blend well with the other components of the substrate.
Its function is to be added to the various cultivation substrates to improve their permeability to air and water as it has a poor holding power of water and nutrients.
It is important not to exceed with its use because it would cause the washing out of the nutritional elements and of the water itself.

Botanical dictionary from A to Z.


or sabatico, adj. [pl. m. -ci] only in the loc. sabbatical year, the one, recurring every seven years, in which the cessation of work in the fields and the general remission of debts were prescribed among the ancient Jews | in the Anglo-Saxon university organization (now accepted in various countries), a year of paid leave to which teachers are periodically entitled to devote themselves to study or scientific research. & nbsp

s.f. in locomotives and tractors, tank, placed near the wheels, containing sand which, in an emergency, is spread over the rails to prevent slippage. & nbsp


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