adapting agriculture in africa to climate change by

Adapting agriculture in Africa to climate change

by

Jens B. AuneDepartment of International Environment and Development

StudiesNoragric

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 micro-

organsims

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?

• 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

Control Priming Priming+

fertilizer (0.3g)

Yields kg/ha 328 435 556

Gross margin (US$/ha) 28.4 57.3 80.0

Value Cost Ratio - - 6.15

Effect of seed priming and micro-dosing on sorghum yields and economic returnAverage for 53 farmers in Kordofan State, Sudan (Dryland Coordination Group)

Seed priming and micro-dosing in Mali.

Non -primed PrimedPrimed + micro-fertilsation

Photo A. Coulibaly

Treatment Yield kg/ha

Control 320

Crop residues 700

N + P fertilizer 900

Crop residues + N P fertilizer 1510

Effect of crop residues and fertiliser on pearl millet grain yields Average of 9 years experiment, Niamey, ICRISAT

Yamoha , Bationo 2002

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

Effect of crop residues and fertiliser on millet grain and straw yields Average of 9 years experiment, Niamey, ICRISAT

Yamoha , Bationo 2002

Effect on fertilisation and crop residue management on pearl millet yield, Niamey, 13 years experiment Source: Bationo and Buerkert 2002

Treatment Organic matter g/kg

Control 1,7

Crop residues 2,1

N + P fertilizer 2,0

Crop residues + N P fertilizer

3,3

Changes in soil organic carbon in top-soil after 13 years of different soil management

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 2009A

vera

ge C

rop

Yiel

ds

Low input Practices

+Current Climate

Low input Practices

+ Climate Change

Improved Practices

+Climate Change

Improved practices

+Improved

germplasm+

Current climate

1 2 3 4 5Management and Climate Scenarios

Current Climate Yield Gap

Improved practices

+Adapted

germplasm+

Climate change

Yield Gap 1

Yield Gap 2