Agriculture Reference
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I = k t
n
(3)
D = k t
n
(4)
where: I = the infiltration rate at time t (mm/min), t = is the time that water is on the
surface of the soil (min), k = the intercept of the curve which represents the infiltra-
tion rate at unit time (instantaneous infiltration rate, mm/min), and n = the slope of
the curve which represent the relation between log I and log t; and D = accumulative
intake rate (mm/min), and Soil pH and EC were measured in 1:2.5 soil water suspen-
sions and in soil past extract, respectively, [43]. The CaCO
3
content, soluble Cations
and anions were measured by Scheibler calcimeter [75] as shown in Table 2. Ground
water was source of irrigation water. Irrigation water analysis is given in Table 3.
Grapevines farm three years old (Thomposon seedless variety) were used in the
present work. Grape yield was harvested in the last half of July (2003 and 2004). The
vines were grown at spacings of 2 × 3 (700-vine/fed). The plots devoted for low-head
bubbler, drip, and gated pipe irrigation 50 × 27 m (1350 m
2
), 50 × 27 m (1350 m
2
) and
50 × 54 m (2700 m
2
), respectively.
The meteorological data of the Central Laboratory for Agricultural Climate
(CLAC), for Shalaqan Weather Station were used to estimate irrigation requirements
as shown in Table 4.
TABLE 2
Chemical analysis of the soil.
Soil
sample
depths
(cm)
Cations (Meq/l)
Anions(Meq/l)
E.C
(dS/m)
pH
Ca
++
Mg
++
Na
+
K
+
CO
3
- -
HCO
3
-
Cl
-
SO
4
- -
0-15
15-30
30-45
45-60
0.40
0.46
0.57
0.48
0.48
0.35
0.55
0.66
0.41
0.51
0.62
0.67
0.19
0.18
0.20
0.16
0.00
0.00
0.00
0.00
0.63
0.76
0.79
0.86
0.49
0.51
0.75
0.66
0.30
0.24
0.40
0.46
7.7
7.6
7.4
7.2
0.26
0.23
0.25
0.27
TABLE 3
Chemical analysis of irrigation water.
Grow-
ing
Season
Cations (Meq/l)
Anions (Meq/l)
E.C
(dS/m)
pH
S.A.R
Ca
++
Mg
++
Na
+
K
+
CO
3
=
HCO
3
-
Cl
-
So
4
=
1st
2nd
2.73
2.81
1.4
1.3
2.19
2.16
0.21
0.23
0.0
0.0
2.4
2.3
2.5
2.7
1.0
1.0
7.3
7.4
0.37
0.35
1.52
1.50
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