Knowledge Base
 

Identification code

PP00082

Project titleof

Study of water-salt regime and indicators of rice irrigation systems irrigation-reclamation network operation

Project location:

The Republic of Karakalpakstan, Chimbay district, "Oktyabr" state farm

Rubric

70.03.21

Rubric (SIC ICWC)

01.20.01.15

Project duration

1971 1975

Project Manager

A.R. Ramazanov, SPA SANIIRI

The Republic of Uzbekistan, 700187, Tashkent, Karasu-4/11

Summary

Investigations on improvement of water use and soil water-salt regime management, irrigated lands productivity increase were carried out in the rice sowing zone of Amudarya low reaches. Territory is located in the North of AmuDarya delta and presented mostly by strongly saline meadow-desert soils. Soils made of clay, loam, clayey sand and sand. Climate is sharply continental. Before rice irrigation systems construction the ground waters with mineralization 0.3-30 g/l were at a depth of 3 -10 m. Experimental Production Plot area is 45 ha. Land use efficiency is 0.71 - 0.83. Over the plot territory the gauging stations, observation wells and piezometers are installed. Instrumental survey of canals and distribution network and salt survey were conducted. After 4-years rice irrigation the salt content in thickness 0 - 3m was 0.23 - 0.42 % and 0.02 -0.07 % - on chlorine-ion. Salt balance of aeration zone was of desalination type. Under basic mineralization of ground water 18.6 - 44,6 g/l after second year of irrigation

it decreased to 7 - 22.8 g/l. At the end of vegetation after 4-year rice cultivation the ground water mineralization was within 7.2 -11.2 g/l. Significant salt quantity from rice irrigation systems territory is removed by drainage outflow. Minimum value of drainage water mineralization (0.76 - 3.22 g/l) was noted in the period of water release from rice fields (June-September). After water release from rice fields at the end of vegetation the salt content in drainage outflow increases (9.49 -11.89 g/l) that is due its formation by inflow from distribution network and saline ground water. Moisture content in thickness 0 - 40 cm before rice sowing was 15,65 % (first year); 14,4 % (fifth year); in thickness 40 -100cm - 22,4 and 24,1 % from soil weight accordingly. After rice harvest it was 25,0 -23,8 (0 -40 cm) and 27,3 -24.1 % (40 -100 cm). In the thickness 100 -150cm soil moisture was 22,8 -24,0 % (spring) and 27,5 -26,5 % (autumn).

Key words

rice hydromodule; rice flood irrigation technology; soil desalination; water- salt regime; water-salt balance; salt removal by drainage outflow.

Bibliography

1. Authors: A.R.Ramazanov, A.R. Kurbanbayev, Kh.I. YakubovTitle: Some issues of Amudarya low uppers reclamation Nukus, "Karakalpakstan", 1978

Monograph includes main results of ecologic-reclamation process research under different crops irrigation development and presents technical and technological recommendations on their management.