This is the third lecture of the course 'Irrigation based Agro-ecosystems' conducted at the Faculty of Social Sciences and Humanities of the Rajarata University of Sri Lanka

1. Rajarata University of Sri Lanka
WRMG 2212
Theory 20 hrs Practical 20 hrs
P.B. Dharmasena
0777 613234, 0717 613234
dharmasenapb@ymail.com , dharmasenapb@gmail.com
https://independent.academia.edu/PunchiBandageDharmasena
https://www.researchgate.net/profile/Punchi_Bandage_Dharmasena/contributions
http://www.slideshare.net/DharmasenaPb

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5. Lesson-6

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Lesson-3

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Lesson-3

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14. Lesson-7
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17. uDÿ nEjqï
uo nEjqï
;rul
nEjqï
jeä nEjqï

20. uQÜgqq lkqj

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– Lesson-7

27. VARIATION OF RAINFALL AND IRRIGATION USE
WITH CULTIVATION TIME
0
200
400
600
800
1000
1200
OCTOBER NOVEMBER DECEMBER JANUARY
MONTH
WATERUSE(MM)
Irrigation requirement
Rainfall use