Organizations and technical staff involved: |
Supervisor/project coordinator: Duynov Ivan
Organization: KyrgNIIRI
Address: 4a, Dushanbe str., Bishkek, Kyrgyz Republic
Other counterparts: Gossu Liya, KyrgNIIRI
|
Summary of research project: |
Objective and technical fields:
Perfection of typical technologies of soil water-salt regime regulation depending on soil salinization and sodification rate and type, groundwater salinity, desalinization schemes and reclamation process tendency with regard to salinity and sodification influence on yield.
Objectives: To develop typical technologies of automated regulation of soil water-salt and nutrient regime on salinizated lands. Technical field – irrigation, drainage, fertilisation.
Scientific and technical approach:
Basement for development was the program “Improvement of reclamated lands efficiency and water resources use in reclamation”. For this it was necessary to create a pilot plot, mount equipment, study the elements of water, salt, heat balance and nutrient regime dynamics, collect and process data and insert it into computer data base. Study importance is that at first time interrelations of sprinkler irrigation on the background of conjunctive operation of vertical and horizontal drainage with fertilisation and their influence on crops yield were investigated.
Environment characteristics:
State farm “Chaldovar” 1 rotation field 3 located 7 km to the east from the central settlement. Hydrological and engineer-geological conditions were studied during specialized survey scale 1:50000 in 1965-1966, soil survey scale 1:10000 in 1968.
Climate is continental. Average annual air temperature is 9.4 oC, average minimum in January –5.8 oC, average maximum in July 23.0 oC. Sum of positive temperatures 3600 oC. Annual precipitation is 382.4 mm, relative air humidity is 64.2 %. Geomorphologically the pilot plot is positioned on proluvial plain which is constituted by quaternary sediments overlaid by loam with thickness of 14-16 m.
Groundwater level is shallow (0-5 m). Artesian water is exposed on depth 16-18, 34-36 and 52-55 m. Artesian head either is equal to groundwater level or is higher than land surface. Hydraulic gradient is 0.004 to the north-east.
Groundwater salinity is 3-30 g/l, chemical composition is sulfate-sodium. Lithologically there is mostly loam with strata of sandy loam and sandy-gravel. Soils are medow, grey-medow and medow-bog. Soil salinity varies within a broad range from slightly to very strongly salinizated. Salinity type is sulfate-sodium-calcium.
Parameters of Pilot Projects and Technical Solutions:
Pilot plot has dimensions 760x860 m and is located within 4 fields of 1-st rotation. Field area is 60 ha from which 48 ha were under sprinkler irrigation by DM-Fregat machine (13 units), 3.5 ha (north-eastern corner) by DU Rosa 3 (10 units) and 8.5 ha (rest 3 corners) by furrow. Field slope is 0.003-0.005. field borders are: irrigation pipelines from the east and west, open collector from the north and electric wire line from the south. Irrigation network is represented by 3 asbestos-cement tubes with distance between them 400 m, diameter 19-45 cm and depth 14-17 cm. Drainage network is represented by close drain of ceramic tubes with diameters 150-200 mm and length 600 cm. Drainage density is 12.5 m/ha, depth is 3.5 m. There are two vertical drainage wells on the eastern and western borders of the plot with distance between them 800 m and 400 m from horizontal drain. Well depth is 105, screen length is 10 m, tube diameter 500 mm, discharge is 30 l/sec.
Water supply to DM Fregat machine was performed from closest pipeline through accumulation reservoir. Management was executed automatically.
Crop pattern in 1982-1988 was represented by alfalfa, corn for silage, sugar beet for seeds, winter rape, wheat and corn for silage.
Irrigation regime corresponded to crops planted. Alfalfa 5-6 years old was irrigated 11-13 times by irrigation norm 5600-7250 cu.m/ha and alfalfa 7 years old – 2 times by norm 250 cu.m/ha; corn for silage – 11 irrigation by norm 3020-6830 cu.m/ha; sugar beet for seeds – 6-7 times by norm 2250-3490 cu.m/ha; winter rape and the first vegetation wheat – 4 times by norm 2270 cu.m/ha and the second vegetation wheat in spring – 2 times by norm 975 cu.m/ha.
Methodology:
Field investigation included the following types of observations: soil water-salt regime dynamics; soil nutrient regime dynamics; soil salinity and sodification; vertical drains operation; horizontal drain outflow; plants growth and crops yield accounting.
Soil moisture and salinization dynamics was observed within 10 horizons (each 20 cm to 1 m, each 50 cm to 3 m and to groundwater level); groundwater level and salinity in 16 wells, located to the east and west from the horizontal drain on a distance of 50, 150 and 350 m in spring and autumn.
The scheme of tests to study soil nutrient stock, water stock, soil salinity, groundwater salinity under 3-rd and more years old alfalfa and sprinkler irrigation was as follows: field size was 4x40 m, 4 times repetition.
As fertiliser ammophos and urea were applied in different options: N60; P30; N60P30. Fertilisation was executed by hand.
Soil sampling for full chemical analysis to the depth of 1 m on 32 fields within 5 horizons in spring and autumn; for moisture on 12 fields within the same horizons 5 times during growing period; mobile nitrogen, mobile P2O5, K2O within 2 horizons - 5 times during growing period; soil sampling within 3 horizons for definition of NPK on 3 sites in spring and autumn. Irrigation and drainage water sampling for full chemical analysis during all vegetation and groundwater in spring and autumn; drainage outflow was observed on horizontal drain by weirs at the beginning and the end of site; vertical drains discharge – by volumetric method every 10 days during all growing period; sprinkler irrigation norm – during all growing period; crops yield – on 32 field according to commonly accepted methodology.
Results:
By investigations of water and nutrient regimes on grey-medow soils of sulfate salinity was found the following:
- It is possible to implement technology of soil water-salt and nutrient regimes regulation with assistance of sprinkler technique DM Fregat and DA Rosa 3 on the background of horizontal drainage together with vertical one;
- Under alfalfa irrigation by DM Fregat unit with irrigation norm 4930-6000 cu.m/ha 1 m-layer soil is wetted thoroughly and soil salinity does not change significantly; hay yield was 13.2-14.6 tn/ha;
- Under alfalfa sprinkler irrigation by DA Rosa 3 unit with irrigation depth 6980-7060 cu.m/ha and autumn irrigations with norm 1400-2100 cu.m/ha not only 1 m-layer is wetted thoroughly but toxic salts are washed out which decreased 2.9 times from 0.463 to 0.161 % within 1 m-layer. Hay yield was 17.3-18.9 t/ha;
- Groundwater level depth depends on vertical drains’ pumping duration; in order to keep it at 2 m-level is necessary to pump water within 100 days during the growing period;
- Optimal diapason of moisture before irrigation is 72-90 % FFMC;
- Under corn for silage irrigation by DM Fregat unit fertilisation by urea was performed in amount of N30 kg/ha for one irrigation; irrigation norm was 6250 cu.m/ha under 10 irrigations; control yield under N60P120 was 32 t/ha; under two fertilisations N120P120 – 37.8 t/ha; under three fertilisations N150P120 – 40 t/ha;
- Sulfate salinizated soils have high stock potassium and need only nitrogen and phosphorus fertilisers;
- Fertilisation by boron-magnesium in amount of 20 kg/ha increases sugar beet seeds germination from 64 to 75 %; sugar beet yield in the first year was 1,14 t/ha;
- Soil salinization assessment by statistic methods for 78 years period under sprinkler irrigation on the background of conjunctive operation of vertical and horizontal drainage showed that toxic salts content significantly decreased within 1 m-layer; within the layers 0-20 and 0-60 cm strongly salinizated soils did not remain; similar changes occured within 100-200 cm layer; groundwater salinity did not change significantly and was within the limits of 2.4-26.9 g/l; drainage water salinity varied from 9.1 to 11.7 g/l, in vertical drains – 0.26-0.37 g/l;
- Actual economic efficiency for alfalfa and corn for silage was 315 rouble/ha.
|
Most recent publications: |
(1) Authors: I.Duyunov, L.Gossu, B.Kharitonov
Title: Groundwater regime under vertical drainage operation and sprinkler irrigation by DM Fregat unit on the pilot plot of the state farm “Chaldovar”
Publication details: Statistic assessment of groundwater level dynamics under conjunctive influence of natural and man-made factors and, in the first turn, sprinkler irrigation and vertical drainage is given. It is shown that these conditions provide groundwater stable regime eliminating 1 m-soil layer salinization
Year of publication: 1985
(2) Authors: I.Duyunov, L.Gossu, V.Sirokha
Title: Grey-medow soils’ water-salt and nutrient regime regulation under sprinkler irrigation by DM Fregat and Rosa 3 on the background of conjunctive operation of vertical and horizontal drainage.
Publication details: This allows to improve water-salt balance and increase hay yield 2.5-3.0 times. Urea fertilisation with water allows to increase corn for silage yield on 25 %. Actual economic efficiency was 250-390 rouble/ha.
Year of publication: 1986
(3) Authors: I.Duyunov, L.Gossu, V.Sirokha
Title: DM Fregat irrigation efficiency on grey-medow salinizated lands of Chu province
Publication details: Field investigations results on the state farm “Chaldovar” pilot plot in 1983-1988 for alfalfa, corn for silage, sugar beet for seeds, winter rape for fodder cultivating under DM Fregat sprinkler irrigation are shown
Year of publication: 1990
|
