Example 1: Storage Volume for Climate Conditions in Bangalore (India)

Table 14.1: Calculation of the storage volume for collecting rainwater for irrigation in Bangalore (India). Precipitation Pre (Muller 1996); Monthly storable precipita­tion STPm with (14.5) and EVpond = 0; ET0 see Fig. 13.1;

CWRm = ET0 X kc(1 + h) x AqMg X dm

For tomato, mean kC = 1.1; (1 + (;) = 1.05; ACr/AG = 0.9

kc(1 + (i) x Acr/AG = 1.04;

CWRm = 1.04 x ET0 x dm From Table 14.1 can be seen:

STPy = Epos STPm = 164.9 l/m2 year Defy = Eneg STPm = 371.2 l/m2 year

Table 14.1 Data for the calculation of the storage volume in Bangalore (India)

Month

Pre l/m2 month

CV l/m2 month

dm

ET0 l/m2 day

CWRm l/m2 month

STPm l/m2 month

STPm

accumulated

Jan

5

4.5

31

2.38

76.7

-72.2

+23.1

Feb

8

7.2

28

2.8

81.4

-74.2

-51.1

Mar

10

9

31

3.35

108

-99

-150.1

Apr

41

37

30

3.3

103

-66

-216.1

May

107

96.3

31

3.3

106.3

-10

-226.1

Jun

74

66.6

30

3.3

103

-36.4

-262.5

Jul

99

89.1

31

3.26

105.1

-16

-278.5

Aug

127

114.3

31

2.9

93.5

+20.8

+ 20.8

Sep

170

153

30

2.34

73

+80

+ 100.8

Oct

150

135

31

2.2

70.9

+64.1

+165.2

Nov

69

62.1

30

2.13

66.5

-4.4

+ 160.8

Dec

10

9

31

2.3

74.2

-65.2

+95.6

Case 2(a): Storage volume per m2 greenhouse area VST = STPy = 165(l/m2) The storage is empty from February until July.

Looking at the accumulated sum of STPm, starting in August, the crop water requirement can be covered for 6 months from August to January by rainwater with a storage volume of 0.165 m3 per m2 greenhouse area.

Updated: June 30, 2015 — 4:25 am