A model to evaluate the
sustainability of mixed crop-
livestock systems
CGIAR Systemwide Livestock Programme
‘Mind the Gaps’ Meeting
Naivasha, Kenya
27-29 April 2011
Chantal Hendriks

Mixed systems
Bachelor thesis from Chantal Hendriks
Supervisor: Jetse Stoorvogel

Article
The assessment of sustainability indicators for mixed
crop-livestock systems in sub-Saharan Africa.
J.J. Stoorvogel1,*, C.M.J. Hendriks1, L. Claessens1,2, and M.
Herrero3
1 Land Dynamics Group, Wageningen University, P.O. Box 47,
6700 AA Wageningen, The Netherlands
2 International Potato Centre, P.O. Box 25171, 00603 Nairobi,
Kenya
3 International Livestock Research Centre, P.O. Box 30709,
Nairobi, Kenya

Contents
• Introduction
• Crop-livestock systems
• The model
• Discussion

Introduction
• Chantal Hendriks, student soil sciens at
Wageningen University
• Research started with a bachelor thesis
• Model to evaluate the sustainability of mixed
systems
– Soil sustainability
– Efficiency of dry matter fluxes

Mixed crop-livestock systems
• Returns of OM to field often low
• High variability (classification needed):
- dominantly livestock grazing on communal land
- cultivation on cropland and livestock is grazing on
own pastures
- cultivation on cropland and livestock in stables
- dominantly cultivation on cropland

Research purpose
• Give a good estimation of:
– Carbon stock
– Carbon balance
– Livestock efficiency
– Livestock intensity

The model
• FSU: Farm section unit (farm characteristics)
• PPU: primary production units (cropland and
grassland)
• SPU: secondary production units (animals)
• RU: redistribution unit
• HH: household
• EXT: extern (e.g. market)

Assumptions
• Single PPU, all plots together
• Take mean slope and slope length of all plots
• Often not all residues are measured. Model
calculates residues with HI
• Animals eat till feed requirement
• Feed – feed requirement = grass intake
• Manure calculated by food efficiency
• Erosion measured by USLE equation

The model
EXT
RU
PPU
SPU
EXT
EXT

The model

The model

Discussion
• Model designed for estimation of
sustainability
• Decision making and scenarios can be based
on this model
• Accuracy of assumptions  sensitivity
analyses