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32ПЛОДОРОДИЕ ПОЧВ
IRSTI 68.05.05.29: 68.05.35
DOI: 10.51886/1999-740Х_2022_4_5
T. Turaev1*, O. Jabbarov1, N. Samatov1 DYNAMICS OF SOIL COVER CHANGE UNDER THE IMPACT OF IRRIGATION AND
MELIORATION
1Soil composition and repository, quality analysis center SUE, 100097, Tashkent, st. Choponota, quarter "C", Uzbekistan, e-mail: soil-uz@mail.ru Abstract. A study has been conducted to determine how modern agriculture impacted the structure and reclomative state of light serazem soils 77 years after land development. In the first place, when analyzing soil survey materials, a change in the structure of the soil cover of light serazems is revealed. Long-term irrigation of light serazem soils causes grassing, which causes groundwater levels to rise. Due to these changes, serazem soils under the conditions of the new soil moisture regime acquired new features and properties that allow them to be assigned to another genetic group which is called the group of semi-hydromorphic serazem-meadow soils. As a result of irrigation, leaching, there are significant changes in the chemical, physico-chemical and agrotechnical properties of soils. This provision can be supplemented with materials that testify to the processes of salinization and desalinization of soils. Long-term irrigation and unregulated water intake in weakly soddy conditions leads to an increase in the level of groundwater, which causes a high intensity of the solonchak process and causes secondary soil salinization.
Key words: light serazems, semi-hydromorphic soils, soil reclamation, solonchak soils, saline soils, humus content, grassing, drainage, irrigation, desalinization, solonchak, drained.
INTRODUCTION The agriculture of the Kashkadarya region is developing in accordance with the tasks and direction of the agriculture of the republic. The total area is 2856.799 thousand hectares, which is 7 % of the total area of Uzbekistan. Agricultural development depends primarily on the structure and quality of land and their rational use. Lack of water is a constraining factor in the development of Kashkadarya's productive forces. A majority of the total area of agricultural land is pastureland, which occupies 79 % of the total area of land. Approximately 65 % of them are located in desert areas where sheep are grazed primarily [1].
Irrigation Basics. Along with the resolution of the water problem, the Kashkadarya region also has large reserves for the development of new lands.
Research object is the serazem-meadow soils of the Kashkadarya region.
Research subject is agrophysical, ag-rochemical and water-physical properties and nutrient content.
Scientific novelty of the research lies in certain changes in the agrophysical, ag-rochemical water-physical properties of soils.
Aim of the research is to determine the agrophysical, agrochemical water-physical properties of solonchak soils and to offer characteristics about the state of soil fertility and their effective use in the future.
MATERIALS AND METHODS
The object of research is serazem-meadow soils of the Kashkadarya region. The studies were carried out according to the standard methods generally accepted in soil science in field, laboratory and cameral conditions. Chemical analyzes were carried out in the laboratory with ISO international certification in the field of soil science, in particular, soil sampling, storage and laboratory experiments were carried out on the basis of the GOST:
17.4.3.01-83 Interstate Standard. The study of the properties of soils with a degraded topsoil based on the GOST:
17.4.2.02-83 Interstate Standard. The con-
tent of calcium and magnesium in soils analyzed based on the GOST 26428-85 Interstate standard. Water extract determination was carried out according to GOST 26423-85 Interstate standard. The humus content analysis performed according to GOST 26213-91 Interstate standard. The mechanical and granulometric composition of the soil is determined on the basis of the O'zDSt 817-97 [2-5].
RESULTS AND DISCUSSION The study is to examine how land development has changed soil structure and the reclamation state of soils over the past 77 years and how modern agriculture has contributed to these changes. The soils of the Kashkadarya region are presented according to the genetic groups of soils of the serazem belt. As a result of analyzing soil survey materials, it is possible to determine, first, the changes in the structure of the soil cover over the past 77 years. Observations of weeding over time have shown a rise in groundwater levels in the presence of irrigation. Accordingly, the Chi-rakchi region's groundwater level rose from 8-10 metres to 2-3 metres, and even
up to 1 metre in some places, over the course of 77 years. The cause of this occurrence is incompatibility between the existing collector-drainage network and the necessary drainage of drainage water under difficult groundwater drainage conditions. Therefore, serozem soils under the new soil moisture regime acquired new features and properties that enable them to be assigned to another genetic group, the semi-hydromorphic serozem-meadow soil group. Hence, irrigation began at the stage of semi-hydromorphic regime of moistening, resulting in intensification of grassing and transition of soils to meadows. The opposite phenomenon is also observed in areas of intensive reclamation, a reduction in the areas of bog-meadow soils.
During irrigation and leaching, soil properties are affected significantly in terms of chemistry, physics, and agrophysics. The following data can be supplemented with materials indicating the processes of salinization and desalini-zation of soils (table 1).
Table 1 - Salinization dynamics for 1936-2013 summer period for the soil area
1936 year
By salinity
total area non saline and weakly saline thousand/ha moderately and heavily saline thousand/ha soloncaks, thousand/ha solonetzic, thousand/ha
463,3 372,6 80,5 8,2 0,5
1966 year
By salinity
total area non saline and weakly saline thousand/ha moderately and heavily saline thousand/ha soloncaks, thousand/ha solonetzic, thousand/ha
463,3 357,9 38,5 4,7 36,0
2013 year
By salinity
total area non saline and weakly saline thousand/ha moderately and heavily saline thousand/ha soloncaks, thousand/ha solonetzic, thousand/ha
460.12 378.9 81.13 - -
Based on the final salinity figures for thousand hectares, and the area of moder-1936-2013, it is evident that the area of ately and strongly saline soils has in-slightly saline soils has increased by 6.3 creased by 0.6 thousand hectares. A signif-
icant amount of solonchaks has also been developed - about 3.5 thousand hectares. These lands have now been classified as weakly and moderately saline meadow soils.
During the period 1936-1966 and 1966 to 2013, solonchaks and solonetzic soils of 8.7 thousand hectares of land moved into the category of medium and strongly saline soils. It can be seen from these data that desalinization has occurred on an area of 70.3 thousand hectares, and salinization of soils have occurred on an area of 49.4 thousand hectares (1966) (table 1). In general, the state of reclama-
tion of the lands has improved, although in some areas the opposite has occurred. Accordingly, in Shakhrisabz, Yakkabag and Chirakchi districts, on an area of 14.2 thousand ha, as well as in Karshi district, on an area of 15.3 thousand ha, the area of saline lands has increased. (1966) The solonchak process is intensified by long-term irrigation and unregulated water intake in poorly drained conditions, causing groundwa-ter levels to rise, resulting in secondary salinization. Changes in soil and reclamation conditions in the context of the administrative districts of the region (shown in table 2).
Table 2 Changes in soil and reclamation conditions in the context of the administrative districts of the region.
1936 year
Number of Depth, in cm Alkalinity Moderately
cuttings НСО-3 % НСО-3 mg/eq
0-30 0,054 0,060 0,057
1 30-50 0,053 0,041 0,047
50-70 0,059 0,037 0,048
70-100 0,054 0,032 0,043
0-30 0,032 0,042 0,038
2 30-50 0,034 0,035 0,037
50-70 0,28 0,024 0,035
70-100 0,038 0,040 0,039
1966 year
Number of Depth, in cm Alkalinity Moderately
cuttings НСО-3 % НСО-3 mg/eq
0-30 0,041 0,053 0,046
3 30-50 0,037 0,059 0,048
50-70 0,032 0,054 0,043
70-100 0,034 0,045 0,038
0-30 0,049 0,051 0,050
4 30-50 0,047 0,050 0,048
50-70 0,043 0,047 0,045
70-100 0,031 0,045 0,038
2013 year
Number of Depth, in cm Alkalinity Moderately
cuttings НСО-3 % НСО-3 mg/eq
0-30 0,038 0,62 0,33
5 30-50 0,037 0,60 0,32
50-70 0,039 0,64 0,34
70-100 0,031 0,50 0,27
0-30 0,034 0,56 0,30
6 30-50 0,041 0,68 0,36
50-70 0,032 0,52 0,29
70-100 0,026 0,42 0,22
CONCLUSION Consequently, the data showed that long-term irrigation causes grassing and groundwater rise.
As a result, serozem soils under the conditions of the new soil moisture regime acquired new features and properties that allow them to be assigned to another genetic group, the group of semi-hydromorphic serozem-meadow soils.
Under the influence of irrigation and leaching significant changes occur in the chemical, physico-chemical and agrophysical properties of soils.
Long-term irrigation and unregulated water intake in poorly drained conditions leads to an increase in the level
of groundwater, which causes a high intensity of the solonchak process and causes secondary salinization of lands.
The correct tillage system with the introduction of crop rotation is of great importance in increasing the yield of agricultural crops. The irrigation regime must be built depending on the depth of groundwater. Land reclamation measures on soils are determined by the need to improve the operation of the collector and drainage network. Drains must be cleaned and deepened to the extent that ground-water can be kept during the growing season at a depth of 2.5-3.0 m from the soil surface.
REFERENCES
1 Kashkadaryo viloyati tumanlaridagi mavzhud fermer huzhaliklari va boshka yerdan fojdalanuvchilari sugoriladigan yer majdonlarining tuprok haritasini tuzish va tuprok sifatini baholash ishlariga tushuntirish hati. "Tuprok tarkibi va repozitorijsi, sifati tahlil markazi" DUK. - Toshkent, 2012.
2 MetodyN agrohimicheskih, agrofizicheskih i mikrobiologicheskih issledovanij v polivny'h ihlopkovy'h rajonah (SOYuZNIHI) - Tashkent, 1963. - 439 s.
3 Mezhgosudarstvenny'j standart GOST: 17.4.3.01-83, izuchenie svojstv pochv s degradirovavshim verhnim sloem pochvyN na osnove Mezhgosudarstvennogo standarta GOST: 17.4.2.02-83.
4 Soderzhanie kalciya i magniya v pochvah na osnove Mezhgosudarstvennogo standarta GOST 26428-85.
5 ENkspress-metod soderzhaniya vodnoj vy'tyazhki, soderzhanie gumusa po GOST 26213-91.
TYËIH
Т. Тураев1*, О. Жaббаров1, Н. Саматов1 СУАРУ МЕН МЕЛИОРАЦИЯНЫН, ЭСЕР1НЕН ЖЕР ЖАМЬ^ЫСЫНЫН, 0ЗГЕРУ
ДИНАМИКАСЫ
1МУК «Топырак,тыц сапасын, курамын жэне репозиторишн талдау орталыгы», 100097, Ташкент, Чопонот к-ci, "Ц" кварталы, взбекстан,
e-mail-uz@mail.ru
Ма;алада к;аз1рп замангы епншыжтщ жер жамылгысыныц курылымыныц 63repyiHe жэне жердi игеруден кешнп 77 жыл iшiнде жецы сур топырактыц мелиорациялы; жагдайына ;андаи эсер eтeтiндiгi аны;талады. Топыра;ты зерттеу материалдарын талдау кeзiндe, ец алдымен, жецы сур топырак;тыц жер жамылгысыныц курылымындагы eзгeрiстeр аны;талады. Ашы; сур топыра;ты уза; уа;ыт суару нэтижесшде шегу баи;алады, ягни жер асты суларыныц децгеш кeтeрiлeдi. Нэтижeсiндe, топыра;тыц ылгалдануыныц жаца рeжимi жагдайында сур топыра;тар оларды бас;а генетикалы; топ;а - жартылаи гидроморфты сур-шалгынды топыра;тарга жат;ызуга мYмкiндiк бeрeтiн жаца белплер мен ;асиеттерге ие болды. Суарудыц, шаюдыц эсeрiнeн
топырактыц химиялы;, физика-химиялы; жэне агротехникалы; ;асиеттершде айтарлы^тай 63repicTep болады. Бул позицияны топырактыц туздануы мен туздану процестерiн кeрсететiн материалдармен толыщтыруга болады. ¥за; уа;ыт суару жэне нашар кургатылган жагдаида реттелмеген су алу жер асты суларыныц децгешнщ жогарылауына экеледi, бул туздану YPДiсiнщ жогары ;ар;ында жYPуiн тудырады жэне топыра;тыц ;аиталама туздануына акеледi.
TYüiHdi свздер: жещл сур топырактар, жартылай гидроморфты топырактар, топыракты мелиорациялау, тузды топырактар, гумустьщ курамы, шегу, дренаж, суару, туздану, сортац, кургатылган.
РЕЗЮМЕ
Т. Тураев !*, О. Жаббаров1, Н. Саматов1 ДИНАМИКА ИЗМЕНЕНИЯ ПОЧВЕННОГО ПОКРОВА ПОД ВЛИЯНИЕМ ОРОШЕНИЯ И
МЕЛИОРАЦИИ
1 ГУП «Аналитический центр качества, состава и репозиторий почв», 100097, Ташкент, Чопонотаул., «Ц» квартиль, Узбекистан, e-mail: soil-uz@mail.ru
В статье выяснено какое влияние оказывает современное земледелие на изменение структуры почвенного покрова и мелиоративное состояние светло-сероземных почв за истекшие 77 лет после освоения земель. При анализе материалов почвеннои съемки, прежде всего, выявлено изменение структуры почвенного покрова светлых сероземов. В результате длительного орошения светло-сероземных почв наблюдается залужение, т.е. подъем уровня грунтовых вод. В результате этого сероземные почвы в условиях нового режима грунтового увлажнения приобрели новые признаки и своиства, позволяющие отнести их к другои генетическои группе - полугидроморфных сероземно-луговых почв. Под влиянием орошения, промывных поливов, происходят существенные изменения химических, физико-химических и агротехнических своиств почв. Это положение можно дополнить, материалами, свидетельствующими о процессах засоления и рассоления почв. Длительное орошение и неурегулированным водозабор в слабодренированных условиях приводит к повышению уровня грунтовых вод, что обусловливает высокую напряженность солончакового процесса и вызывает вторичное засоление почв.
Ключевые слова: светлые сероземы, полугидроморфные почвы, мелиорация почв, солончаковые почвы, засоленные почвы, содержание гумуса, залужение, дренаж, орошение, рассоление, солончак, дренированныи.
INFORMATION ABOUT AUTHORS
1 Turaev Toziboy - Scientific Supervisor, candidate of agricultural sciences, e-mail: sitoraboltayeva98@gmail.com.
2 l Zhabbarov Odil - General Director, Doctor of Philosophy in Agricultural Sciences (PhD), e-mail: soil-uz@mail.ru.
3 Samatov Nuriddin - International relations specialist, e-mail: nuriddinsama-tov99@gamil.com.
