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Identification code |
PP00081 |
Project title |
Strongly saline soils water-salt regime study in Karshi
Steppe Charachyl sink |
Project location: |
The Republic of Uzbekistan, Kashkadarya oblast (Karshi Steppe), state farm ¹
11 |
Rubric |
70.03.21 |
Rubric
(SIC ICWC) |
01.20.01.15 |
Project duration |
1974 - 1976 |
Project Manager |
Gulchekhra Khasankhanova, Uzmeliovodkhoz (Sredazgiprovodkhlopok) |
Summary |
Investigations, directed on improvement of water-salt
regime management of irrigated saline soils, were carried
out on basis of moisture availability assessment criteria
improvement for soils of different mechanical composition.
Climate is characterized by high temperatures all year
around Soils are meadow-desert, meadow-takir, etc. Setting
up water and salt regime field studies, capillary-sorption
potential of soil moisture, mineralization of soils and
ground waters were implemented on 2 plots with area 25 ha.
Plots were equipped by registration and observation means.Estimations of summarized potential of soil moisture
show that during all period of study it is found in easily
available form in root layer shortly only during irrigations.
During 3 – 10 days moisture remains at a depth of 25-75
m medium-available, then, in process of dehydration, turns
into category of hardly available and non-available form
for plants. Actually, irrigation intervals of 20-30 days are overestimated.
They should be reduced down to 10, maximum 15 days. Observed irrigation depths (800 -2300 m3/ha)
under annual irrigation norm during vegetation about 4000-5000
m3/ha are insufficient. Existing ground water
regime (below 2.0 -2.5 m) allows water supply increase
for desalination speed by 1.5-2 times. Data analysis allowed
to conclude that the conditions formed in root layer (characterized
by soil moisture potential values) are very dynamic and
vary in a greater degree than moisture both during of non-irrigations
period and during the year.
Analysis of field and laboratory study allows to determine
bounding empiric relations between salt composition and
osmotic pressure of soil solution as well as distinguished
graphs of capillary-sorption pressure from moisture for
soils of different mechanical composition, that allows to
carry out the assessment of soil moisture availability through
data of usual analysis of soil extract and soil structure. |
Key words |
irrigation regime; salt regime; soil salinization;
soil moisture |
Bibliography |
1. Authors: A.N.Morozov, A.I. Artyukhova, V.N. IgnatikovTitle: Estimation of soil solution osmotic pressure
on specific electric conductivity of soil extract. The collection
of works of "Sredazgiprovodkhlopok" Institute
and SANIIRI, Tashkent, 1978Comparison of specific conductance values and easily
soluble salts in soil extracts is given in 1:5, 1:1 and
soil solutions extracted under "soil-water" ratio
of 1:0,4 - 0,3 that enable to find the dependence, allowing
by chemical analysis data to estimate specific conductance
of soil solutions and their osmotic pressure.2. Authors - M. Kh. Kondrakov, F.V. Serebrennikov,
A.N. MorozovTitle: Research studies under development of projects
on irrigation and new lands reclamation. The collection
of works of "Sredazgiprovodkhlopok" Institute
and SANIIRI, Tashkent, 1979
The achievements of "Sredazgiprovodkhlopok"
Institute were represented for the last years in the field
of research studies and their role in irrigation system
improvement on large reclamation objects- Golodnaya, Karshi
Steppes, etc. Materials on developments efficiency in the
field of irrigation regimes, drainage, irrigations technology
and saline lands are given. |
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