Presentation by Mark T. van Wijk, Mariana C. Rufino and Lieven Claessens (WUR) to the:CGIAR Systemwide Livestock Programme Livestock Policy Group meeting, 1 December 2009
Modelling approaches to address crop-residue tradeoffs in mixed crop-livestock systems
1. Modelling approaches to address crop-residue tradeoffs in mixed crop-livestock systems Mark T. van Wijk, Mariana C. Rufino and Lieven Claessens Wageningen University, Plant Production Systems email: [email_address] CIP, Nairobi Presentation: CGIAR Systemwide Livestock Programme Livestock Policy Group, 1 December 2009
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4. Theory of intensification (from a NRM perspective) After: McIntyre et al. 1992, Fernández-Rivera et al. 2002
10. NUANCES-FARMSIM FIELD: dynamic, summary model of CROP and SOIL processes LIVSIM: individual based dynamic, summary model of livestock HEAPSIM: dynamic summary model of manure management and storage LABOURSIM and CASHSIM: summary models of socio-economic components and their interactions with production comp.
11. Trade off analysis N losses at farm scale [kg season -1 ] Farm scale maize yield [kg season -1 ] Tittonell, Van Wijk et al, 2007, Agricultural Systems 0 1000 2000 3000 4000 5000 6000 7000 8000 80 100 120 140 160 180 200
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13. Analysis with crop residues: results of a sensitivity analysis Van Wijk et al, 2009, Agricultural Systems
14. Degree of crop-livestock integration Stocks, flows and assets System state II + + Management intensity + + System state III System state I Household “Well-being” Stress Alleviation Tittonell, Van Wijk et al, 2009, Agricultural Systems
16. milk feed $ feed $ $ feed crop residues nutrients $ fertilisers On-farm Rented land manure Investment capacity Labour availability Access to credit Access to information
17. milk feed $ feed $ $ feed crop residues nutrients $ fertilisers On-farm feed crop residues nutrients $ fertilisers Where to invest How many cows? What type of feed? How much fodder produced on-farm? How long can this be sustained? manure Rented land
20. Dury, Rufino, Van Wijk, De Ridder, Zingore and Giller, 2009 AEE submitted
21. Analysis tools Parameters Input data Biophysical world Expert knowledge Experimentation Surveys Simulation models
22. Analysis tools Parameters Input data Biophysical world Expert knowledge Experimentation Surveys Decision world Preferences Opportunities + Interviews Surveys Simulation models Optimisation tools
23. Analysis tools Parameters Input data Biophysical world Expert knowledge Experimentation Surveys Decision world Preferences Opportunities + Interviews Surveys Preferences One decision maker (DM) Multiple DMs Influenced by the environment Opportunities Resources available Inputs prices Outputs prices Simulation models Optimisation tools
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Editor's Notes
Figure 11: Schematic conceptualisation of pathways towards intensification and their potential impact on household well-being. In this case, the impact of intensifying crop-livestock interactions (x-axis) on different aspects of household well-being (y-axis) such as food security or cash income follows a discontinuous trajectory in which input-intensification (quantitative) must be followed by qualitative changes in the productive structure of the farm to induce ‘jumps’ of the system towards higher states. Resource use efficiencies, the degree of complementarities between production activities, resource endowment and management intensity increase from system states I to III. Stressing factors (e.g. population density) and alleviation interventions may modify the slope of the trajectory towards higher levels of well-being for a certain degree of intensification.
At relatively low levels of intensification, we may find these elements in the dairy systems. To sustain milk production and cash flow, the soil productivity must be sustained. If there is investment capacity, fertilisers are used. But in the long term, attention needs to be paid to soil C. And therefore using crop residues and manure rationally may help to sustain the feed production on-farm.
Let’s imagine a more intensified farm, where the farmer is conscious of the need of keeping the soil productivity, increase herd size, and to supply feed to the cattle expand the cropping land, and the use of concentrates. Still has many decisions to make to allocate the resources.
Or may decide to purchase a piece of land and produce his own grass, for which investments are needed. This farm look much more complex in structure and in the type of decisions to be made than the first one.
Or may decide to purchase a piece of land and produce he own grass, for which investments are needed. This farm look much more complex in structure and in the type of decisions to be made than the first one.