Transcript Adapting agriculture in Africa to climate change

Adapting agriculture in Africa to climate
change
by
Jens B. Aune
Department of International Environment and Development
Studies
Noragric
Norwegian University of Life Sciences
Soil organic matter - a key to adaptation to climate change
• Increase soil water holding
capacity
• Improves infiltration of water
• Reduce soil temperatures
• Improves soils ability to store
nutrients
• Aeration
• Provides media for soil microorgansims
Message from World Congress of Conservation
Agriculture (2009) in India:
• 2,5 tonn of organic matter should
be recycled every year
Why is it difficult to recycle enough
organic materials?
• Biomass production is low, often below 1 t/ha
• The biomass production is used for other
purposes (fodder, builing materials). Low
recycling of soil organic matter.
• Plouging reduces the soil organic matter
How to increase biomass production?
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early sowing
good quality seeds
correct spacing
appropriate varieties
water harvesting/irrigation
Integrated plant protection
Integrated Plant Nutrition Management
Trees on farm land
Seed priming:
• Soaking of seed for 8
hours in water
• Facilitates crop
establishment
• Yield increase 20-30
%
• Feasible in pearl
millet, sorghum,
cowpea, groundnuts,
maize and sesam
Effect of seed priming and micro-dosing on sorghum yields and
economic return
Average for 53 farmers in Kordofan State, Sudan (Dryland Coordination
Group)
Control
Priming
Priming +
fertilizer (0.3g)
Yields kg/ha
328
435
556
Gross margin (US$/ha)
28.4
57.3
80.0
-
-
6.15
Value Cost Ratio
Seed priming and micro-dosing in Mali.
Non -primed
Primed
Primed + micro-fertilsation
Photo A. Coulibaly
Effect of crop residues and fertiliser on pearl millet grain yields
Average of 9 years experiment, Niamey, ICRISAT
Treatment
Yield kg/ha
Control
320
Crop residues
700
N + P fertilizer
900
Crop residues + N P fertilizer
1510
Yamoha , Bationo 2002
Effect of crop residues and fertiliser on millet grain and straw yields
Average of 9 years experiment, Niamey, ICRISAT
Treatment
Yield kg/ha
Straw yield
Control
320
1390
Crop residues
700
2560
N + P fertilizer
900
3060
Crop residues + N P
fertilizer
1510
5400
Yamoha , Bationo 2002
Effect on fertilisation and crop residue management on pearl millet yield,
Niamey, 13 years experiment Source: Bationo and Buerkert 2002
Changes in soil organic carbon in top-soil after 13
years of different soil management
Treatment
Organic matter g/kg
Control
1,7
Crop residues
2,1
N + P fertilizer
2,0
Crop residues + N P
fertilizer
3,3
Breaking the vicisous cercle low yield and
decling soil organic matter content
• Ensure good agronomy
• Use micro-dosing of fertiliser and seed
priming
• Use mulch, particularly in drought prone areas
• Minimise ploughing
Permanent soil cover in
conservation
agriculture
How to retain mulch in dryland is a
challenge
• Increase biomass
• Increase fodder production
• Demonstrate Integrated Plant Nutrition
Management and conservation agriculture
• Development of other types of renewable
energy
• Improved grazing management
• Build local institution for land-use
management
Integration of trees into the farmland
Source: Chris Reij
‘Hypothesis of Hope’ Schematic Framework. ICRISAT 2009
Average Crop Yields
Current Climate Yield Gap
Yield Gap 2
Yield Gap 1
Low input
Practices
+
Current
Climate
1
Low input
Practices
+
Climate
Change
Improved
Practices
+
Climate
Change
Improved
practices
+
Adapted
germplasm
+
Climate
change
2
3
4
Management and Climate Scenarios
Improved
practices
+
Improved
germplasm
+
Current
climate
5