Identification code

PP00072

Project title

Development of technologies for reclamation state regulation using drainage and leaching of soils under backwater conditions created by Kayrakkum reservoir

Project site

Republic of Tadjikistan, Leninabad province, Khudjand rayon, collective farms located in Chkalov scheme

Rubric

70.03.21; 70.21.39; 38.61.27

Rubric (SIC ICWC)

01.20.01.15; 01.45

Project duration

1973-1978

Project manager

I.S.AliyevResearch Institute for Soil Science

Rudaky avenue, 21a, Dushanbe, Republic of Tadjikistan

Summary:

The research dealt with salinity control and land productivity rise on the basis of increased drainability and leaching under ground water dam, as well as with an optimal management by soil water-salt regime through the development of reclamation-environmental regimes for land productivity and farm profitability raise. The scheme is located in West Fergana and joins to the south-west bank of the Kayrakkum reservoir. The climate is dry continental. Relief - submountain plain. Lithology of the profile is characterized by pebble sediments with sandy loam and loam interlayers.Ground waters are bedded at a depth of 1,5-3,5 m with toxic salts content equal to 1,0-2,5 g/l; chemical composition is chloride-sulphate. Soils are sierozem and meadow. Area of the scheme, comprised by 4 farms, is 6000 ha.Irrigation network is laid in earthen channel. Efficiency of the network is 0,55-0,6. Specific extent of drainage network is 36 linear meter/ha, while its depth is 1,5-2,5 m. 50% of drainage network is in unsatisfactory conditionIn south frontier of the scheme a line of vertical drainage wells was constructed to catch deep release from Arkin scheme (Kyrgyz Republic).

Obtained results allow one to form negative soil water-salt balance, to manage the efficiency of leaching and irrigation in salinized soils, to determine and regulate depths and salinity of ground waters. Ways to reduce toxicity of residual salinity by fertilizing are found. Reclamation-agronomic characteristics of soils were determined. These assist to develop optimization measures as well as soil salt regimes under different leaching degree. Possibilities of saline drainage water use for irrigation are studied. Character of reclamation-environmental processes within the scheme is determined. Role of ground water inflow from the mountainous side of irrigated lands and ground water dam, created by the Kayrakkum reservoir, is determined. Applicability of systems approach for analysis of reclamation regimes is studied.

Key words

Soils, water-salt regime, water-salt balance, leaching, drainage flow

Bibliography

Author(s): Kh. Yuldashev, A.G. VaksmanTitle: Soil salt regime regulation within the zone of backwaters created by Kayrakkum reservoir

Publication details: Materials of studies on identification of methods for determination and development of optimal soil-environmental state of irrigated lands within the zone of backwaters created by Kayrakkum reservoir are given. Factors of water-salt regime formation in Chkalov scheme, the methods and results of field studies, accountings, experiments, and additional materials used for the balance are considered.