1 in field rainwater harvesting for improved maize production (synthesis results – lessons &...
TRANSCRIPT
1
In field In field Rainwater Harvesting for Rainwater Harvesting for Improved Maize Production Improved Maize Production
(Synthesis Results – Lessons & Challenges)(Synthesis Results – Lessons & Challenges)
By
Mário Chilundo & Paiva MunguambeMário Chilundo & Paiva Munguambe
UEM-FAEF
Final Scientific Workshop
JHB, 15-18th June 2009
2
Main Objective of the trialsMain Objective of the trials
Increase water availability for crop growth
though in field water harvesting technique
Semi-Arid region
October to March: rainy season with 75 % of the annual rain;April to September: dry season with 25 % of the annual rain.
Chókwè’s average annual rainfall: 582.0 mm
Introduction…Introduction…Introduction…Introduction…
6
Balanço hídrico(Pr-ETc)
Water balance (Pr-ETc)Water balance (Pr-ETc)Water balance (Pr-ETc)Water balance (Pr-ETc)
MethodologyMethodology
• On station trials (EAC)
• Design: RCBD
• Crop: Maize (Matuba: 120 days; Potential yield: 5-6 ton/ha)
• Seasons (2006/07; 2007/08 and 2008/9)
• Mulch: 20 ton/ha (vegetable residues)
• Rain gauge: Precipitation
• Parameters: plant height and grain yield
RWT principle RWT principle • RWT: Catchment area covered by PVC plastic
• Ratio: control S80 (80*30 cm; 1:1); S160 (160*30 cm; 1:2) and
S240 (240*30 cm; 1:3) – 8 rows/plot (6 effectives+ 2 border)
Cropping Area (CA)
80X30 cm
Catchment Area (CTA)
160X30 cm
Ratio (CTA/CA) = 2:1
Plastic cover
Maize grain yield (ton/ha)Maize grain yield (ton/ha)
11
a
a
B
A b
C
2007/08
Total of 392 mm
2008/09
Total of 471.1 mm
Estimated Costs (500 mEstimated Costs (500 m22 plot) plot)
13
Quantity Costs (USD)
Activity Unity Control (1:1) T2 (2:1) T3 (3:1) Control
(1:1) T2 (2:1) T3 (3:1)
PVC Plastic m - 204 156 - 306 312
Seeds kg 2 0.5 0.3 2 0.5 0.3
Sowing Unity 1 1 1 15 10 5
Weeding Unity 3 1 1 45 15 15
Total 62.0 331.5 332.3
14
Ratios 1:2 (S160) and 1:3 (S240) increased water availability for
the crop, resulting in higher grain yields per plant and thus
increase WUE;
Climate change vs rainfall patterns vs sowing dates need to be
addressed because they will have impact on the yields;
Need to test other “local” material as alternative due to high
investments costs (plastic) ;
Need to consider IPDM and fertilizers to increase water
productivity and yields
Final remarks/challengesFinal remarks/challengesFinal remarks/challengesFinal remarks/challenges