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Characteristic of the humus




The humus is a type of the soils which are formed under steppe and forest-steppe vegetation of a suborealny belt. Are formed generally on carbonate maternal breeds - the loess, the lyossovidnykh clays and loams, sometimes on more ancient limestones, sandstones, marlaceous clays in the conditions of not washing or periodically washing water mode. For the humus accumulation of organic substances in the humic and accumulative horizon, the high maintenance in it of a humus, well expressed
lumpy -granular structure, high potential fertility are characteristic.

The first scientific regulations on an origin of the humus are available in M. V. Lomonosov's works (the middle of 18 century) who considered that these soils were created as a result of decomposition of vegetable and animal organisms. At the end of 18 - the beginning of 19 centuries P. Pallas, etc. made a hypothesis of a sea origin of the humus and considered it as the sea silt which remained after retreat of the Caspian and Black seas. This hypothesis has only historical value; it reflects the idea of the soil existing at that time as about geological education. Insolvent was also a hypothesis of a marsh origin of the humus

.

The grassy vegetation annually leaves in the soil a large number of an opad - the vegetable remains which 75 - 85% make roots. Hydrothermal conditions of steppe and forest-steppe zones favor to hymification process as a result of which difficult humic connections (generally humic acids) giving to a soil profile dark coloring are formed. The best conditions for process of hymification are created in the spring and at the beginning of summer. At this time in the soil a sufficient reserve of moisture from autumn and winter rainfall and snowmelt, favorable temperature condition. In the period of a summer siccation microbiological processes considerably weaken that protects humic substances from a fast mineralization. At decomposition of the vegetable remains rich with cindery elements and nitrogen, the bases (especially a lot of calcium) with which humic substances are sated are formed. It promotes their fixing in the soil in the form of humates and to preservation in the top horizons of the humus of reaction, neutral or close to it. Humus most intensively proceeds in a forest-steppe zone where the best moistening promotes more powerful development of grassy vegetation, active hymification of its remains. In a steppe zone insufficient moistening determines the smaller depth of penetration of roots, decrease in quantity of the opad coming to the soil and its fuller decomposition.

 

humus types

The humus is divided into two gradation: on the power of a humic layer and according to the maintenance of a humus.

On the power of a humic layer the humus is subdivided on:

• heavy-duty (power more than 120 cm);

• powerful (120 - 80 cm);

•so-so the powerful (80 - 40 cm);

• low-power (less than 40 cm).

According to the maintenance of a humus the humus can be divided on:

• corpulent (more than 9%) - coloring black;

• srednegumusny (6 - 9%) - coloring black;

• low-humus (6 - 4%) - coloring dark gray;

• slabogumusny (less than 4%) - coloring gray;

• microhumus (less than 2%) - coloring light gray.

On type chernozems happen:

• opodzolenny chernozems;

• lixivious chernozems;

• typical chernozems;

• ordinary chernozems;

• southern chernozems.

Allocate also mitselyarno-carbonate humus which are formed in areas with warm winter (the soil doesn't freeze through), and the humus developing in the conditions of winter frost penetration. Depending on salinity allocate usual, carbonate, solonetzic, solonetzic солончаковатые and others.

Application of the humus The humus is ideal for any kind of landing. He doesn't demand additional processing and use of organic and mineral fertilizers. In the conditions of good moisture content the humus is very fertile - it can be used for cultivation of grain, vegetable and forage crops, at cultivation of gardens and vineyards, in the ozelenitelnykh works in landscaping.

Most often the humus is used for formation of a certain reserve of fertility of the soil. Introduction of the humus even to the most exhausted soil conducts to its improvement, recovery of all its characteristics, first of all water penetration, enrichment by nutritious elements. Especially considerable effect is swept up at application of the humus on easy sandy and sandy soils.

Allocate also micellar-carbonate humus which are formed in areas with warm winter (the soil doesn't freeze through), and the humus developing in the conditions of winter frost penetration. Depending on salinity allocate usual, carbonate, saline soil and others.

 

 

Application of the humus

The humus is ideal for any kind of landing. He doesn't demand additional processing and use of organic and mineral fertilizers. In the conditions of good moisture content the humus is very fertile - it can be used for cultivation of grain, vegetable and forage crops, at cultivation of gardens and vineyards, in the works in landscaping.

Most often the humus is used for formation of a certain reserve of fertility of the soil. Introduction of the humus even to the most exhausted soil conducts to its improvement, recovery of all its characteristics, first of all water penetration, enrichment by nutritious elements. Especially considerable effect is swept up at application of the humus on easy sandy and sandy soils.

 


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