Mechanical composition of the soil waters, climate, and soil has direct influence in forming of the saline soils. Or to be truer, the drier the climate, the more white clay in the mechanical structure of the soil, the salinization of soils would go more rapidly. It has been clear in the result of carrying out investigations that if level of the soil waters is 1.5-3 meters, in this case generation of saline soils is must.
Moreover, saline land can be formed with the help of artificial irrigation, too. Such saline soils are called "repeated saline soils». Forming of saline soils passes in nature in two ways:
1) Irrigation methods passes to soils and get into contact with soils waters an gathered on top layer of soil at result of high evaporation.
2) Salty irrigation waters accumulate gradually salts in soil and so form repeated saline soils in the result of evaporation.
Composition of the salts is very different in saline soils. From salts which have been spread most are:
Na Cl, Na2 SO4, Na2 CO3, Na H CO3, Mg Cl2, Mg SO4, Mg CO3, Ca Cl2, Ca CO3 and Ca SO4.
Accumulation of such salts in soil is foremost condition for forming of the saline soils. It is necessary to note that if some salts mentioned above are considered necessary for life of fauna some of them have harmful influence on development of plant. Particularly chloride salts have big obstacles in development of plant. It has been found in the result of researches that if amount of chloride and sulphate salts in soil is 0.1%, in such cases plants germinates very weakly. This percentage of these salts if are 0.3 05%, then plants perish completely.
Perishing of the plants comes as result of influence of some salts on plant roots as harmful matter. Soda (Na2 CO3) can be shown from matters being harmful for plants especially. It has been found in the result of experiments that if amount of Na2 CO3 in soil solution is more than 0. 005% the plant perishes in such case. As there are compounds of Na Cl Mg Cl2, Ca Cl Cl2 besides salts they are considered as harmful salts for plants, too. But Ca CO3 and Ca SO4 salts are harmless compounds for plants. Indicator of the salinity degree of soils is an amount of common salts. But amount of these salts in soils can raise 3-5% an sometimes 30-40%. Therefore, generally saline soils are divided to following types according to the degree of salinity: Weak saline, middle saline, strong saline and saline soils and they are distinguished from each other. Saline soils are divided into following types according to composition of the some salts, and ions of salts:
1) Chloride saline soils.
2) Sulphate saline soils.
3) Carbonate saline soils.
But for cations there are 3 more types Na saline, Mg and Ca saline. As a whole more of less some salts have morphological influences on salts. For these reasons saline soils are divided into 3 genetic types.
1) Soft saline soils.
2) Wet saline soils
3) Black saline soil
Soft saline soils: are spread in the drought regions in heights. Top layer of these soils is salty and dry. At simple motion of a man on saline soils their top may become dusty.
Forming of soft saline soils is connected with presence of much Na2SO4 salt in the soil.
Wet saline soils: These soils differ from saline soils with upper dusty layer. Contrarily top layer of wet saline soils is always dump and blackish. These forms salt crust of 2-4 cms of thickness on top layer of these soils at hottest weather. CaCl2 salts has spread most in structure of the wet saline soil. Essential feature of the salt is hygroscope of salts. That is it holds dampness in the damp air in itself and it always keeps the top layer of the soil) in the damp situation. Such soils are called as wet saline soils.
Black saline soils: it resembles much to wet soils according to outward appearance. But these top layers of this soil has blackish color. One of essential features of the black saline soil is much amount of Na2 CO3 salt compared to all another salts in structure.
Presence of sodium in these soils creates alkali reaction and it solves little organic matters being in the soil and gives blackish color to the top layer of soil. In general, as saline soils are not suitable for plants in most cases these soils remain unused.
Saline soils.
These soils are specified with presence of natrium cation in absorption complex. Moreover top layers of the saline soils are washed from soluble salts. In general saline soils are formed from washing of saline soils. In some circumstances in the result of influence of the waters of salty soils, salty soils can pass to saline soils. Therefore, depending on climate condition of the area, influence of the soil waters and nature of mother rock in some periods, at damp seasons the saline soils are washed off temporarily and turn to salty soils and in drought seasons contrarily salty soils turn to saline soils. Presence of Na cation in saline soils has influence on its chemical structure and physical property. Therefore, Na cation creates alkali reaction in the soils in the first place, truly speaking Na2 CO3 (soda) create the alkalescence reaction in saline soils that was noted.
Formation of sodium in saline soils can be explained with reaction noted below (to absorb) Na + Hs + COs 2 = (to absorb) H + NaHCOs 3
Presence of H + NaHCO 3 compound in salty soils lose the stabilities of colloid particles being in the soil and it causes their washing and soils lose its structure becomes being dusty. Organic matters of the soil are carried out to bottom layers in the result of alkali reaction being washed. If this reaction will last for a long time the upper layer of salty soils gets lightened in color.
By physical property some negative signs of the saline soils appear, too. While damp muddy top layer is formed in the damp circumstances it forms thin crust. Presence of much salt in illuvial soils this layer is divided to vertical cracks and forms column type structure becoming broken to pieces. It is considered as typical feature of salty soils.
But elluvial layer turns to grey ash color under influence of washing process. Sometimes the structure of this layer is not like that. As we noted above, upper layer of salty soils are completely washed off from salts but illuvial layer is enriched with salts. Saltiness degree of these soils is defined by amount of Na cation. Therefore, salty soils: strong saline, saline and weak saline, and they are differed each from other.
Malt soils.
"Malt soils" are said soils that formed at result of deeply changing in the natural condition inside of the saline soils. Academician Hedroits describes generating of malt soils as described below. In connection with presence of Na cation in saline soils alkali reaction arises. This alkalescence turns organic matters of soil to soluble condition and creates condition for washing of soils and gradually organic matters of saline soils get reduced. Moreover alkali reaction influences to colloid of the soil, too. Or to be more true under influence of Na cation "Hel" cations begin to change to «Zol" colloids and washed out from soil. Later absorption complex of salty soils absorbing complex of saline soils gets broken to parts under influence of the water because weak system (due to Na cation). Later after washing out of humat compounds of absorbing complex its gets broken to pieces in alimo silicate part. At result of this broken case silicate, iron hydrates and aluminium hydrate are formed. Iron and aluminium hydrates are washed to bottom layers in the result of influence of the water. But silicate compounds are accumulated in elluvial layer in the amorphous shape. So, saline soils either from morphological side or for chemical composition turn to completely other soil. As we noted above the process of turning of saline soils mentioned above to new soils type is called as «malting process" and soils formed in result are called s “malt soils” .
Malt soils have special morphological structure. Such soils have "A"layer of open grey color but (B) alluvial layer is of whitish color. İlluvial (C) layer have iron compounds in very seldom cases, too. From this point of view malt soils have similarity with podzol soils slightly. At last malt soils have one more features that is "H" cation in absorption n complex.
So, evolution scheme of the salty soils can be described as given below.
Salty soils were formed from washing of the saline soils, and malt soils formed from change of salty soils. All three soil types are stages of salty soils all of them have genetic interconnection.
Improvement methods of the salty and saline soils.
It is necessary to take definite measures in the farming for usage of the salty and saline soils. It is necessary to wash off saline soils with the help of the waters for its improving. Therefore, it is advised to wash saline soils in winter seasons. Moreover it is possible to improve saline soils with special engineering methods, too.
It is necessary to cut the influence of the waters of salty soils to prevent of its salinization in the first place. If influence of soil waters continues to the soil, salts are washed with the help of the same waters of irrigation temporarily but during drought these soils can again get salinized. Special “drainage” methods were offered to improve them during carrying out of engineering methods. At that special canals (drainages) are dug in the definite depth and distance in the area which turned saline and during irrigation these salty water gather in the canals being filtered from soils layer. Separate drainages are joined with main canal (collector) and salty soil and irrigation waters are taken to outside places with the help of the special diesels. After washing of saline soils few times like this, it is necessary to cultivate there perennial plants. Roots of these plants improve the structure of the soil, and it carries their physical property, or to be more true becoming aired, water-resistant and such other properties to normal state. It is necessary to carry out some chemical measures to improve the saline soils. As we know presence of Na cation in absorption complex of salty soils is specific feature of these soils namely Na cation causes salinization in soil. Therefore, salty soils are plastered with gypsum. Purpose of this action is to replace Na cation with calcium.
[absorption compl] Na + Cas SO4 = [absorption compl.] Ca + Na2s SO4
So, after replacing of absorption complex of salty soils with calcium first of the structure of these soils are improved it durability to water gets increased. Structure turns to receives small nut like shape and bio-chemical processes occurring there get normalized and soils are enriched with organic matters gradually. After such chemical measures soils can turn to cultural and productive soils.
Formation process of the laterit type soils.
Laterit, red and yellow soils
Laterit types of soils have occupied big areas in the Earth. These soils had taken its name from “later” word. In Greek it means "brick". The color of these soils in fact is red brick like color.
Laterit type of soils includes laterit, red and yellow soils. Tropical zone where laterit soils were spread has below mentioned climate. Rainfall here is 1500-2000 mms, average annual temperature reaches 25-30°. Atmosphere has also high dampness, too. The climate that we noted has direct influence on land formation. It creates first of all conditions for intensive becoming broken of organic matters. Almost no zone does split the organic matters like tropical zone in the Earth. Under influence of high temperature and dampness plant remainders completely get mineralized and at result CO2, nitrogen and sulphuric acid are formed. Insignificant part of plant remainders turns to humus. Strong erosion starts mineral compounds of soil at result of splitting of these organic matters. Sometimes this process continues so long that laterit soils become difficult to separate from mother. But plant cover consists of grassy plants from one side and constant green forest lands from other side in the tropical zone. Typical laterit soils have developed under forest plants. Regarding mother rock, silicate and alimo-silicate rich rocks were spread here. It includes particularly rocks like gneiss, granite, diabase, diorite and basalt. Process of lateritization and laterit soils have developed over sediments of weak sandy, mergel and sand soils with alimo-silicates. Relief of the tropical zone is rather uneven. Land formation process of laterit type soils passes under influence of splitting of organic and mineral matters. From chemical point of view upper layer of typical laterit type soils is rich with iron oxides but amount of SiO2 and Ca, Mg matters is few. In spite of majority of the plant remainders, humus matter is few in laterit soils. In average humus of laterit soils does not exceed 6-7%.
Iron compounds are visible in illuvial layers of laterit soils in a form of thin crust and congression. Rixtgofen shows that thickness of the laterit soils is in 10 meters. Therefore these soils are considered as ancient generated soils. Laterit soils, podzol soils are considered as from clayey unsaturated soils. Therefore hydrogen ion calcium, Mg is high in absorption complex. Reaction of the soil solution is acid.
Another kind of the laterit type soil is red soils. They sometimes are called as Terra-rossa". These soils differ from laterit soils with absence of iron compounds and with less thickness of soil layer. Such soils are found in the shores of Black Sea, in Hungary and Romania. According to chemical composition Mn compound is found mostly in these red soils.
These compounds give reddish color to soil. Likewise laterit soils the red soils are also considered as soils with unsaturated bases, and their reaction is also sour. Amount of humus in these soils does not exceed 2-3% in the soil. Sometimes one can meet the process of podzolling in red soils, too. Finally yellow soils make a passage between laterit and red soils. These soils are found widely in Transcaucasia, in Georgia and Azerbaijan. For chemical composition yellow soils are rich with iron oxides and they are characterized with less humus.
Yellow soils are undergone to podzolling process under influence of the high dampness. Therefore sometimes clear and sometimes hidden podzol layers are found in yellow soils. If we have looked through information that we gave about above laterit soils, it is possible to say that laterit type of soils are contrary profile of the podzol soils. If podzol soils gather one and half of compounds of oxide (Al2 O3, Fe2 O3) in the soils in bottom layers, but in laterit type soils these compounds have been gathered in the top layers mostly. For example SiO2 compounds relates to it. Despite of it, formation of laterit type soils passes under process of formation like podzol soils. Under influence of high dampness laterite soils turn to unsaturated condition by bases under influence of washing of organic matters, splitting of absorption complex and water like it happens in podzol soils and in podzolling process. Therefore land formation process in laterit type of soils happens similar to land formation process in podzol soils. From view point of farming worthiness laterit soils are considered as valuable soils.
Therefore citrus plants found suitable conditions for itself in these soils.
Soils of the upland countries located in the territory of the USSR.
Upland countries have occupied big territory in soils of the USSR. Special relief of the countries, condition of climate influence the land formation process and soil cover, which are different compared to plain regions. Vertical spreading is most characteristic feature for upland regions. Or to be more true by climbing up various soil zones replace each other gradually. Character and spreading in some upland regions of the soil types is very different. It is necessary that all upland regions in the territory of the USSR are divided to following areas: Caucasian, the Crimea, the Ural and Central Asia.
Caucasian: Land cover of the Caucasian is complex and different quite. Because this mountain region creates condition for passing of land formation process in various ways with climatic condition, plant cover and such natural conditions according to relief or geological system. Because there are more high mountains in the Caucasian, vertical zone law of the soil has been developed most of all here. It is possible to say that to find al types of lands in the territory of the USSR. Even change of some soils has been spread wider in the plain part of the territory of the USSR. For instance: Alps consisting of rich pastures here concerning to the plant cover compared to tundra zone, then zone of high upland forest, plain zone, desert-plain, subtropical zone can be found here. At result of researches carried out by professor Zakharov all Transcaucasia is divided into west, east and south land provinces.
Western Transcaucasia.
By climbing to high mountainous region from Black Sea shores following land zones are located in this area:
1) Bog podzol zone: This zone has been located in the Kolkhid plain mostly. Because climate of this zone is damp so bog, half bog and bog podzol soils has been developed here wider.
2) Podzol-red soil zone: It is located in the lower mountainous part of the western Transcaucasia and at foothills. It has humid moderate climate. Forest plants have been developed here. Regarding mother rocks limestone and deluvial sediments are found here mostly. Land cover consists of various red and podzolled red soils.
3) Mountain –forest zone: It occupies a wide area in 600-2000 meters height. It has very uneven relief, and the climate is humid moderate cold, too. Different crystalloid rocks have been developed here. Land cover consists of podzolled brown forest land, podzolled and rotten carbonate land.
4) Mountain- meadow and mountain-tundra zone: It occupies non-forest area in 2000 meters height. Here one can meet glaciers les or much. Its climate is cold, and plant cover is sub-alp meadow plants. Mainly land plants and peaty mountain–meadow soils are spread mostly here.
Eastern Transcaucasia (Azerbaijan)
Climatic condition of Eastern Transcaucasia is contrary of the western Transcaucasia. As climatic condition of this area compares from west Transcaucasia completely, so quite another soil zones are developed here.
1) Grey land zone: It occupies all Kur-Araz Lowland. Relief is plain, the climate is drought and continental. Amount of the rainfall is 200-300 mms. Average annual temperature is 13-15°. Mother rocks consist of ancient and modern alluvial sediments. Deluvial sediments can be met in the edge part of the Kur-Araz Lowland, too. Plant cover consists of Ephemera (short-term plant) and xerophytes plants. Land cover consists of different grey land. Salty and saline land has developed in the some sloping places, too. Finally weak bogged lands have been spread in the banks of Kura, too.
2) Chestnut and brown soil zone: This zone surrounds less parts of the foothills zone. For its climate Kur-Araz Lowland is relatively damp. Amount of the rainfall reaches 400 mms.
Plant cover consists of plain plants. Regarding mother rock, lös like clayed merkols and sandy parts may be noted here. From types of basic land chestnut and brown soils are spread here. As we noted above salty and saline soils were developed in the Kur-Araz Lowland in sloping places, too.
3) Black soil zone: This zone occupies upper part of chestnut brown soils and located between forest and desert plain zone. Black soil zone in Azerbaijan was developed in the upper part of Small Caucasus Mountains. Its climate has rather humid, very different and rich plant cover.
Formation of black soils in the eastern Transcaucasia is generated in the forest land tracts. While forest cover is perished by naturally or artificially by men gradually plain plants begin to cover this area. From influence of this plant cover old forest lands change deeply for morphological and chemical structure and turns to black soils. For this reason at the lower layers of black soils of Azerbaijan clayed layers inherited from forest soils are also found. For black soil zone spreading of carbonated black soils is characteristic, too.
4) Mountain-forest zone: This zone has been located between black soil zone and mountain-meadow zone in the 2000-2600 meters height. But amount of the rainfall is 500-1200 mms, temperature is 6°-12°. Plant cover consists of plants of very different forest. But land cover is on grey, brown soils and at skeleton forest soils in upper part of zone.
5) Mountain-meadow and mountain-tundra zone: It has been located in the 2800 meters heights of the eastern Transcaucasia. As it was in other zones climate of mountain–meadow zone has cold and short summer season in (the) another zones to (the) season (part) of very cold and short summer, too. Mountain-tundra zone occupies only high mountainous peaks in eastern Transcaucasia. Typical Alps and subalps plants have been developed. Depending on natural condition, process of land forming passes here very weakly. Therefore one can meet primitive soils, which have been weakly developed in the mountainous-meadow zone. Especially, it is possible to show soils characteristic to this zone like peaty and fatty mountainous-meadow soils. First one occupies upper part of the peaty zone and the second surrounds bottom part of the zone. As a whole, a characteristic sign for this land is being with skeleton, too.
Southern Transcaucasia (Armenia)
This zone surrounds the Armenian mountain plateau and middle valley of the Araz zone. Climate is continental, rainfall is less. Volcanic rocks have been spread from mother rocks mostly. Regarding plant cover it is constant without forest zone. Typical plain plants, subalp and alp plants in the heights of this zone and xerophytes plants in the southern part were spread. Land cover consists of mountain-meadow, black soils, and southern part consists of grey land.
Dagestan.
As natural condition of Dagestan is sharply different in the Caucasian the land cover here is rather different. As we know relief of the Dagestan is very difficult the mountain-meadow soils with skeleton developed weakly in mountain zones. Being specific for this zone sometimes naked precipice rocks and washed soils types can be found in this zone. Grey forest lands and rotten carbonated lands were spread in middle mountain parts of Dagestan. Mountain-forest zone passes directly to desert-plain zone but brown lands at foothills and grey lands have spread in plain zones. Spreading on grey lands of the salty and saline lands is considered from characteristic cases. At last, narrow sandy strips and sandy hills are met in the shore of the Caspian Sea.
The Urals.
The Ural Mountains has fewer heights comparatively, and it lies till 2500 kms. Therefore, vertical spreading laws of soils specific to mountainous countries are not met here clearly. In most cases land cover of this place consist of podzol type soils. North end of the Ural Mountains consist of mountain -tundra lands and it consists of peaty swamps. Stony, fatty meadow lands are developed in the tops of the some high mountains, forest zone. At last, black land and changed black soils have been developed in the bottom foothills of the Ural Mountains.
The Crimea.
In spite of the minority of the area of the Crimea, land formation process and land cover is very different there. Northern part of the Crimea consists of areas of typical plain. Chestnut lands developed under the plants. Plain zone and forest-meadow zone is located in the South side of the Crimea. Following soils were developed in upland zone:
I Subalp soilsr.
1) Subalp blackish mountain-meadow soils
2) Subalp dark colored forest soils
3) Brown forest soils
II Brown forest soils
1) Brown forest podzolled soils
2) Brown forest dark color soils
3) Brown forest carbonated soils.
III Mountain black soils
1) Washed black soils
2) Carbonated black soils.
IV Crimean Black sea shore red colored soils.
V Carbonated rotten soils.
Types of land that we noted above replace each other by turn while climbing to heights from bottom according to vertical spreading law. Subalp soils have been developed in the plateau of the Crimea. Blackish and mountain-meadow soils have been located here mostly. These soils have clear granular structure; an amount of humus is 16-20%. Mountain-meadow soils have been developed in the western part of the plateau. Brown forest soils are spread in upland part of the Crimea, too. These soils are located mostly under beech forests mostly. At last, when move to the east while drought of the climate increases in the east part of the plateau one can meet types of washed black land and changes of the carbonate black lands. At last, at southern edge of the Crimea red colored subtropical land is spread, too.
