Science Forum 2013 (www.scienceforum13.org) Breakout Session 9: Farm Size, Urbanization and the Links from Agriculture to Nutrition and Health Ken Giller

1. Farming Systems and Agronomic Perspectives
on Changes in Farm Size
How small is beautiful?
Ken Giller, Linus Franke, Huib Hengsdijk, Leonard
Rusinamhodzi, Greta van den Brand and others
Plant Production Systems, Wageningen University, The Netherlands
Mark van Wijk
ILRI, Nairobi, Kenya
Bernard Vanlauwe
IITA, Nairobi, Kenya
Humid Tropics
A ‘‘‘‘uniquely’’’’ African green revolution
Kofi Annan called for ‘a uniquely African green revolution in the
21st Century’
Recognising:
• the rich diversity of Africa’s people, soils and farming
practices
• the urgent need to increase agricultural productivity
But how do we target technologies to the huge diversity and
heterogeneity of African farming systems?
Gradients of soil fertility
• Broodtekst corps 18 News Gothic regular
Poverty leads to soil degradation - western Kenya
Resource-rich farm
Resource-poor
farm
Photo: Pablo Tittonell
Farmers’ management decisions
MKT CSH
CNS
HOME
LVSTK
OE
WOOD
Cash
Labour
Nutrients
Resource allocation patterns
To different
activities
To different
fields
Tittonell, Vanlauwe, Leffelaar, Shepherd & Giller (2005)
Ag. Ecosyst. Environ. 110, 166-184.
AfricaNUANCES
Typology of farms
Family
composition
Resource
endowment
Production
orientation
Site-specific
factors
Resource
allocation
strategies
Tittonell, Vanlauwe, Leffelaar, Rowe & Giller (2005)
Ag. Ecosyst. Environ. 110, 149-165.
Resources
Time (life cycle)
Expanding
family &
resources
Sub-dividing
land
Establishm
entandgrowth
Declineanddissolution
Maturity
Maintaining &
reproducing
resources;
production
may exceed
consumption
The farm development cycle
Chayanov (1925)
AfricaNUANCES

2. NPK
NPK
NPK
Options
NUANCES-FARMSIM: farm-scale modelling approach
Tittonell et al. (2007) Fld Crops Res. 100, 348-368; Rufino et al. (2007) Livestock Sci. 112, 273-287; Chikowo et al. (2008) Ag. Syst. 97, 151-
166; Tittonell et al. (2009) Ag. Syst. 101, 1-19; van Wijk et al. (2009) Ag. Syst. 102, 89-101; Tittonell et al. (2010) E. J Agron. 32, 10-21.
Tittonell et al. 2009 Agric. Syst. 101, 1-19
Smallholder livestock farms in western Kenya
Farm Type 2
0
10
20
30
40
1 4 7 10 13 16 19
Farm Type 1
0
10
20
30
40
1 4 7 10 13 16 19
Farm Type 3
0
10
20
30
40
1 4 7 10 13 16 19
Farm Type 4
0
10
20
30
40
1 4 7 10 13 16 19
On-farm production
Household requirement
Number of growing seasons
Caloricenergy(MJfarm-1season-1)
NUANCES-FARMSIM – impacts on household food security
Tittonell et al. 2009 Agric. Syst. 101, 1-19
Putting nitrogen fixation to work for smallholder farmers in Africa
How to increase inputs from N2-fixation
• Increase the area of land cropped with legumes
(targeting of technologies)
• Increase legume productivity – agronomy and P
fertilizer
• Select better legume varieties
• Select better rhizobium strains and inoculate
• Link to markets and create new enterprises to
increase demand for legumes

3. control +Pfert +ino +Pfert+ino
Soybean response to P and inoculation in Nigeria
N2Africa demonstration trial results in Nigeria 2010
0
1000
2000
3000
4000
5000
0 1000 2000 3000 4000 5000
SoybeangrainyieldwithPand/orI(kg/ha)
Soybean grain yield in control plot (kg/ha)
SSP, no I
No SSP, I
SSP + I
Soybean response to P and inoculation in
Ghana and Nigeria
0,0
0,5
1,0
1,5
2,0
2,5
3,0
3,5
0,0 0,5 1,0 1,5 2,0 2,5 3,0 3,5
Yield in controltreatment (t/ha)
With P
With I
With P + I
Ghana Nigeria
N2Africa demonstration trial results in Ghana and Nigeria 2010
0,0
0,5
1,0
1,5
2,0
2,5
3,0
3,5
0,0 0,5 1,0 1,5 2,0 2,5 3,0 3,5
YieldintreatmentswithPand/orI(t/ha)
Yield in controltreatment (t/ha)
With P
With I
With P + I
Non-responsive soils
Prospective- Mg - P
- micronutrients control
Putting nitrogen fixation to work for smallholder farmers in Africa
Yield gaps are poverty traps!
1. A poverty trap is "any self-reinforcing mechanism
which causes poverty to persist”
2. Non-responsive soils are widespread poverty traps
3. Nutrient inputs are needed to restore productivity
4. Mineral fertilizer alone is not enough – need to
(re)build soil organic matter
5. Animal manure is a scarce resource – not available
to the poor
Tittonell, P. and Giller, K. E. (2013) When yield gaps are poverty traps: The paradigm of
ecological intensification in African smallholder agriculture. Field Crops Research 143, 76–90
.

4. Putting nitrogen fixation to work for smallholder farmers in Africa
0,0
0,5
1,0
1,5
2,0
2,5
3,0
3,5
Availablefarmland(ha)perhouseholdmember
Numberoffarms
Resource endowment
FT4 FT3
FT1 & FT2
FT5
Land area per household member
ISPC foresight study on urbanization & farm size
process | summary of results | data and methods
Data and methods behind our conclusions
Source: Adapted from Giller (2013)
Numberoffarms
Resource endowment per farm
Expansion of relatively
big farms
Increasing number of
the smallest farms
Stylized changes for
Kenya 1997-2010 and
Rwanda 1990-2000
Expanding the biggest farms usually implies
shrinking land available for the smallest
Farm size distribution is like a balloon:
Typical distribution of farm sizes (e.g. lognormal)
0
5
10
15
20
25
30
35
40
45
50
< = 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 > 1
% farms
farm area/capita(ha/pers)
Mozambique
Ghana
Zimbabwe
Malawi
Nigeria
Kenya
DRC
Rwanda
Land availability distribution in N2Africa target areas
N2Africa Baseline 2010
0
10
20
30
40
50
60
< = 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 > 1
% farms
farm area/capita(ha/person)
Vihiga (HH)
Migori (HL)
Bondo (LH)
South Gem (LL)
Land availability distribution in four regions of Kenya
N2Africa Baseline 2010
Food self sufficiency and land surplus or shortage?
Farm land gaps
Zooming in, where will value chains work?
Potential financial returns of soya cultivation on surplus land

5. Potential financial returns of maize and soya intensification Closing yield gaps for maize and legumes with inoculant
Value chains and safety nets…?
Vorley, del Pozo-Vergnes, Barnett, 2012. Small producer agency in the
globalised market: Making choices in a changing world, London.
Seville, Buxton, Vorley, 2011. Under what conditions are value chains effective
tools for pro-poor development? IIED/Sustainable Food Lab, London.
Climbing beans in DRC
No manure
With manure
Long rains season 2010 in Sud Kivu, DRC
maize following maize maize following climbing beans
Pigeonpea-maize intercropping in southern Africa
Legume residues removed from the field

6. Residual effects of pigeonpea intercrops and sole crops on maize
Rusinamhodzi, Corbeels, Nyamangara, Giller 2012 Field Crop Res 136, 12-22
Nutrition Impact Study in Northern Ghana
• Diet of N2Africa subjects is more nutrient adequate
• Subjects <2 years of female N2Africa farmers have a higher
IDDS compared with male N2Africa farmers
Individual dietary diversity
N2Africa subjects and non-N2Africa subjects
Non-N2Africa
villages
(n=202)
N2Africa
villages
(n=129)
Characteristic Mean (SD) Mean (SD)
IDDS (14 food groups, 0 to 14) 5.1 (1.8) 5.5 (1.9)*
*P<0.05 (Mann-Whitney U test)
Ilse de Jager, Abizari Razak and Inge Brouwer, 2013
Putting nitrogen fixation to work for smallholder farmers in Africa
Conclusions
1. Small farm size and poor soil fertility present
double poverty traps
2. Ex ante analysis can assist in advising policy
and development agencies
3. Market-led value chain approaches do not
serve the poor(er) households – safety nets?
4. Legumes nitrogen fixation can increase
yields and dietary diversification for nutrition
5. Small is beautiful – but how small?
Putting nitrogen fixation to work for smallholder farmers in Africa
For updates see
www.N2Africa.org
Lots of video resource materials
N2Africa Podcaster - Monthly Newsletter
Giller et al. (2011) Agricultural Systems, 104, 191-203.
Humid Tropics CRP