A model to evaluate the sustainability of mixed crop-

livestock systemsCGIAR Systemwide Livestock Programme

‘Mind the Gaps’ Meeting

Naivasha, Kenya27-29 April 2011

Chantal Hendriks

Mixed systems

Bachelor thesis from Chantal HendriksSupervisor: 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 Netherlands2 International Potato Centre, P.O. Box 25171, 00603 Nairobi, Kenya3 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

PPU

SPU

RU

EXT

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