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Section 11. Agricultural sciences
DOI: http://dx.doi.org/10.20534/ESR-17-1.2-174-177
Amanov Bahodir Tuhtasinovich, senior scientific researcher of the Department of "Irrigation and hydraulic structures" of Andijan Agricultural Institute E-mail: [email protected]
Substantiation of the order of the calculations and specifications crop irrigation Currently
Abstract: The article presents the demonstration calculations to refine the methods of crop irrigation regimes adaptation FAO international methodology on materials perennial local research showed them that opportunity, that is, transition to a single for irrigated areas all over the world.
Keywords: Landscape, agrolandscape, irrigation norms, the growing season, the way of irrigation, fluid and electrolyte balance, FAO, CROPWAT, soil.
In Uzbekistan, there are 4.27 million hectares of irrigated areas, and are currently in the design of irrigation systems for their timely and in the right amount of irrigation and watering clarification about the documents used alone, and in the operation of irrigation systems in the basin administrations of irrigation systems — Other documents [1; 2; 3].
Applicable regulations are based on field studies conducted 30-40 years ago. To date, mineralization of irrigation water increased by 2-3 times, changed the soil and hydrogeological conditions, the earth underwent artificial drainage, and they have different fertility [4]. There are a number of recommendations for the calculation of the order of irrigation of agricultural crops [5; 6; 7 et al.], However, these recommendations do not fully take into account the above changes.
Figure 1. The general sequence of order of priority irrigation of agricultural crops and rationale specifications water needs
Substantiation of the order of the calculations and specifications crop irrigation Currently
Here: ETo — standard évapotranspiration [mm day-1], Rn — net radiation on the upper surface [MJ m-2 day-1], G — intensity soil heat flux [MJ m-2 day-1], T — the average air temperature at a height of 2 m [° C], u2 — wind speed at a height of 2 m [m-1], es — saturation vapor pressure [kPa], ea — actual vapor pressure [kPa] (es- eS) — vapor pressure deficit of the air [kPa], delta — pressure curve slope pair [kPa ° C-1], y — psychrometric constant [kPa ° C-1]
Temperature, humidity, duration of wind and sunlight in areas where no observations were made on the balance of Radiation calculated according to the information [9]. Evapotranpiration crop flow is designed according to the following formula:
ET = K ■ ET0 (2)
here: Kc — coefficient accounting water consumption sowing.
Based on many years of experience ISMITI (formerly SANII-RI) PSUEAITI (formerly UzPITI), Research Institute of grain and leguminous crops on irrigated land, and other research institutions, in view of ripening, resistant to salinity and drought varieties, refined AR for the calculation of the water consumption of local crops.
Table 1. - The coefficients of the phases of development of agricultural plants, calculated on the FAO methodology
autumnal wheat
Indicators groundwater level, m The phases of development of crops
1 2 3 4
19.11-20.01 21.01-26.02 27.02-30.04 1.05-20.06
1 2 3 4 5 6
Kc no $AO 0,35 0,75 1,15 0,20
Kc 2004-2005 y. y. 1,5 0,40 0,72 1,19 0,49
Kc 2006-2007 y. y. 0,64 0,73 1,24 0,35
Kc. average 0,46 0,73 1,20 0,42
Kc 2004-2005 y. y. 2 0,38 0,68 1,19 0,49
Kc 2006-2007 y. y. 0,62 0,73 1,23 0,34
Kc average 0,50 0,71 1,21 0,42
Kc 2004-2005 y. y. 2,5 0,37 0,68 1,19 0,49
Kc 2006-2007 y. y. 0,62 0,73 1,23 0,34
Kc. average 0,49 0,71 1,21 0,41
Kc 2004-2005 y. y. 3 0,37 0,68 1,19 0,49
Kc 2006-2007 y. y. 0,62 0,73 1,23 0,34
Kc. average 0,49 0,71 1,21 0,41
Corn
Indicators groundwater level, m The phases of development of crops
1 2 3 4
2.07-11.07 12.07-13.08 14.08-02.09 03.09-30.09
Kc $AO 0,4 0,8 1,15 1,10
Kc 2005-y. 1,5 0,67 0,91 0,96 0,9
Kc 2005-y. 2 0,61 0,73 0,94 0,89
Kc 2005-y. 2,5 0,59 0,71 0,91 0,82
Kc 2005-y. 3 0,56 0,69 0,91 0,81
Cotton
Indicators groundwater level, m The phases of development of crops
1 2 3 4
14.05-31.05 1.06-21.07 22.07-30.08 1.09-30.09
Kc by $AO 0,4 0,75 1,15 0,7
Kc 2006-y. 1,5 0,38 0,71 1,16 0,91
Kc 2006-y. 2 0,32 0,62 1,05 0,68
Kc 2006-y. 2,5 0,29 0,59 1,02 0,63
Kc 2006-y. 3 0,28 0,57 1,01 0,63
Therefore, this article put forward recommendations for the transition to a single method of FAO for the irrigated areas of the world, as well as in the Republic it is necessary to make appropriate adjustments Change, and on the subject based on the results of years of research and developed recommendations.
The general sequence of the order of priority irrigation of agricultural crops and justification specifications need for water is shown in Figure № 1.
When approaching the order of irrigation for crops FAO methodology, data weather station is widely used, is located close to the object, on the calculation formula Penman-montain.
Under the standard of the water needs of crops (UTB) means "water flow size used for evapotranspiration, allowing disease-free growing on a large field to the plant, without limitation, using fertility and soil moisture to reach the full potential for fertility."
0.408AR -G) + Y^00°73ui(es -ea) ETo =--T + 273
A + /(1 + 0.34u2)
1 2 3 4 5 6
peas
Indicators groundwater level, m The phases of development of crops
1 2 3 4
17.11.05-1.03.06 2.03.06-24.04.06 25.04.06-17.05.06.
Kc by $AO 0,3 0,7 1,0
Kc 2005-2006 y. y. 1,5 0,47 0,66 0,90
Kc 2005-2006 y. y. 2 0,42 0,63 0,87
Kc 2005-2006 y. y. 2,5 0,39 0,63 0,84
Kc 2005-2006 y. y. 3 0,38 0,63 0,83
Note: Kc-achieved indicators in lysimeteres during field studies (for the main agricultural crops and repeated)
To determine the size of the capillary humidified groundwater root soil analyzed local lysimeter studies (Katz D. M., Kiseleva S. P., Rahimboev F. M., Amanov H. A., Krilov M. M., Bespalov N. F., Ry-zhov S. N., Ikramov R.K et al.). The FAO manual studied the em-
pirical relationship between the. level of groundwater with different mechanical structure, located below the root layer of capillary moisture and speed up, and taken three typical profiles (easy, medium and hard) soil ground (2 table).
Table 2. - FAO listed in the manual approximation equation empirical relationship between the level of groundwater with different mechanical structure, located below the root layer of capillary moisture and speed up
Name of soil profiles Empirical equations of approximating Correlation coefficient
1 eHruA G = 6.1264 e-0,043H R2 = 0,9899
2 ypTa G = 16,675e-0'028H R2 = 0,9218
3 OFup G = 18,348e-0'042H R2 = 0,9145
For their practical use at the Institute of Soil Sciences zoning maps for the profiles of three typical soils selected from kartagramm «soil quality assessment» will be developed, designed for the active layer of 2 m above the aeration zone.
The procedure for watering crops and standards requirements in a biological water will be identified by the following equation:
B = W - W - P - G + ET
(3)
Here: We — spare soil moisture at the end of the month, mm; Wb — soil moisture reserve in the beginning of the month, mm; Pe — precipitation, mm; Ge — Receipt of underground water, mm/Coon
In determining irrigation norms during vegitatsii in the root layer can increase the need for water for flushing the second salinity.
The rate required for one irrigation is revealed by the following formula:
d = (p•Sa) • D / Ea (4)
Here: p — The share of the available soil moisture; Sa- available soil moisture, mm; D — The depth of the root system, m; Ea — irrigation efficiency;
The formula determining the time between waterings:
i = (p • Sa) • D (5)
Construction of field irrigation schedule for each type of plant is calculated by months, the water balance is calculated by the following formula: (root layer?)
W = W, + G + P - ET
(6)
In determining the order and irrigation standards specified in the manual FAO efficiency for cotton adopted as 0.65. In our conditions in the fields of literature, the efficiency is given as 0.55 - 0.75. As IMIS can be taken as 0.669 - 0.729 [10; 11]. When watering the crops and the use of water saving technologies (laser land leveling, irrigation furrow to furrow film pulling or mulching with straw, instead of the main ditch the use of portable chutes et al., Which can raise the efficiency of up to 0.95.
Currently, necessary comprehensively examine the depth of groundwater, soil salinity and mineralization ofwater provided for irrigation, the total drainage ofland, irrigated regimes expressing general
and special water-salt balance and harmonize the relationship of order and irrigation norms "vegitatsionny" and "nevegitatsionny "period. This is done using a method developed in ISMITI [12].
To substantiate the aeration zone of irrigated land and the best water-salt balance of the upper layer of groundwater can use a computer program «WASTER»:
dw d dt dx
K (W ) ^ dx
- e (w, x ),
y = -K (W ) dH dx
d(wc) d (d» dc ^ d(vc)
dt dx I dx I dx
(7)
(8)
(9)
Here:
H — generalized potential soil moisture, m;
H = P (w)-x (10)
P (W) — capillary potential (pressure) m; x — the vertical coordinate (x = 0 on the surface of the soil, a positive direction down), m; W — volumetric moisture, m3/m3; By (W) — hydraulic conductivity coefficient; e (w, x) — function selection of moisture by plant roots; V — moisture transfer speed, m/day; C — the salt concentration in the pore solution, g/l; D * — factor of convective diffusion of salts; t — time, day.
With the help of the above differential mathematical models can calculate the drainage of land (the value to be confirmed by the calculation of the total and private water and salt balance), and to determine crop irrigation schedule.
The above FAO manual method of determining the washing of salts based on the leaching of salts from the soil like a "piston", which gives extremely high standards of salt leaching. However, in our region, water shortage is difficult to achieve. Therefore, according to the recommendations ISMITI advisable to define standards "novegitation" watering.
For the accumulation of moisture glaze made in the second half of February and beginning of March, in conditions not salty and a little salty automorphic soils (groundwater level below 3 m) up to
Land meliorative status in irrigated lands of Syrdarya province
2000 m 3/ha of water. On hydromorphic lands (groundwater level 1,5 + 2 m) and with a shallow layer of soil (0.5 + 1m) should not sand and pebble artificial soil moisture accumulation ratios exceed 1000 + 1500 m3/ha. In our conditions, to determine the salt leaching standards V. R. Volobuev expedient to use the formula.
N = 10000 • h • lg(5n /Sd)a (11)
Here: N — leaching rates, m3/ha; h = capacity of the washed soil-ground layer, m; Sn — salt content in the layer is washed prior to washing (% of dry weight soil-ground); Sd — allowable salt content (% dry weight of soil-ground); a — salting rate determined according to experimental industrial washings. Significance soleotdachi depends on water-physical properties of soils and their changes for a variety of loam within the following limits:
- For light mechanical composition depending on the composition of salt — 0.62 (chloride — Cl = 40-60%) — 0.82 (sodium sulfate);
- For the loamy soils of the inhomogeneous structure corresponds a = 0.92 (chloride type of salinity) — 1.12 (sodium sulfate-type);
- For clay or loam with low salting a = 1.22 (chloride type of salinity) — 1.42 (sodium sulfate), etc.
The formula for the calculation of V. R. Volobuev less salting land reduces the rate of salt leaching, thus it is advisable to salt leaching standards equate to the above regulations moisture accumulation.
In our conditions, the main method of combating soil salinity is to build on fields year-round washing mode.
Kp --^P+N1^-WW (12)
ETC
CP is the coefficient of leaching regime of irrigation land is based on many years of advanced materials, on the recommendation should be K = 1.1-1.2.
p
In justifying modes and agricultural irrigation standards must take into account a variety of weather conditions and crop technology. To account for the changing weather conditions by way of watering crops as the main option, you must take the totality of precipitation in vegitation period. Calculation of one-time and seasonal irrigation standards for FAO methodology and program SROPWAT to evaluate the efficiency of water use in irrigation systems, water saving in the current and future level of development, water use criteria with a decrease in water supply, determine the exact water needs and water management features.
To determine the norms washing salinity V. R. Volobuev expedient to use the formula. In view of the above, the calculation of one-off and seasonal irrigation standards the same for all irrigated areas of FAO method and program CROPWAT should be used in the Republic of Uzbekistan respectively, adapting and making adjustments.
References:
Schroeder V. R., Safonov V. F., Vasiliev I. K., Parenchik R. I., Riftin A. R. Calculated values of irrigation norms of agricultural crops in the basins of the Amu Darya and Syr Darya rivers. - Tashkent. - 1970. - P. - 292.
Bespalov N. F., Malabaev N. I., Mambetnazarov B. S., Kuchkarov D. K. Irrigation of crops of cotton crop rotation (hydromodule zoning and modes of crop irrigation by regions of the Republic of Uzbekistan). - Tashkent. - 1992. - P. 191.
Schroeder V.R, Vasiliev I. K., Trunov T. A. Hydromodule zoning and calculation of irrigation norms for cotton in the arid zone//Prob-lems of design and efficiency of the irrigation systems in Central Asia collection of scientific papers, - Issue 8, - 1977, - P. 28-41. Ikramov R. K. Clarification of irrigation scheduling of crops and hydro-zoning of irrigated land - the actual problem//O'zbekiston rçishlorç hyzhaligi, - No. 3, - 2015. - P. 32 b.
5. Kostyakov A. N. Fundamentals of reclamation, - M.: Sel'khozgiz, - 1951. - P. 652.
6. Hachenko S. I. Water regime management on reclaimed land in the non-black soil zone (hydrological aspects). - A.: Gidrometeoizdat, - 1987. - P. 239.
7. Kwan R. A., Vyshpolsky F. F., Zhdanov G. N. Irrigation norms of crops in Kazakhstan (recommendations). - Zhambyl, - 1990. - P. 75.
8. FAO materials on Irrigation and Drainage 24. "Water consumption selhozkultur" Scientific Information Centre of the Interstate Coordination Water Commission (SIC). - Tashkent. - 2000. - P. 127.
9. Publications FAO Irrigation and Drainage 56 "Evapotranspiration plants" Scientific Information Center of Interstate Coordination Water Commission (SIC). - Tashkent. - 2001. - P. 296.
10. SNIP 08/02/03 85 Drainage systems and facilities/USSR State Building. - M.: TSITP USSR State Committee. - 1986.
11. Laktan N. T. Watering cotton - M. Kolos, - 1978. - P. 175.
12. IkramovR.K. Principles of management of water-salt regime of irrigated lands of Central Asia in the conditions of water scarcity/Tr. SANIIRI. - Tashkent: GIDROINGEO, - 2001. - P. 191.
13. Ramazanov A., Yakubov H. washings and recharge irrigation. - T.: Mehnat, - 1988. - P. 192.
DOI: http://dx.doi.org/10.20534/ESR-17-1.2-177-181
Begmatov Ilkhom Abduraimovich, Tashkent Institute of Irrigation and Melioration, Uzbekistan.
E-mail: [email protected]
Land meliorative status in irrigated lands of Syrdarya province
Abstract: Article describes the assessment results of land meliorative status in new improved complex approach in districts of Syrdarya province. Research was mostly conducted in the districts. Moreover, the recommendations for improvement of each district is presented.
Keywords:vegetation period, groundwater mineralization, soil salinization, irrigated lands, cadastre, land meliorative status, water supply, wells, closed horizontal drainage.
