Potential of social-ecological modelling to
understand dynamics of pastoral land use
under processes of change
Birgit Müller, Gunnar Dressler, Felix John
ADRAS-Workshop ILRI, June 2015

Content
1. Junior Research Group POLISES
2. Methods: Social-ecological modelling
3. Study 1: Stylized modelling study: Side effects of rain-index
insurance on sustainable land use
Study 2: Polarisation between pastoralists
Study 3: Multi-agent model on pastoral land use of Borana
4. Further ideas for collaboration (Social networks, Board
game on nomadic land use)
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Junior Research Group POLISES:
„Global food security policies and their social-ecological
side effects in regions prone to global change”
Team: Head + 2 PhDs  Postdocs, foreign fellows
Duration: Aug 2014 – July 2018 (+ 1 year)
Funding: By German Ministry of Research (1.3 Mio €)
Objectives
• explore the impacts of global food security policies on local land use
strategies
• investigate the resulting social-ecological resilience of land users (in
particular pastoralists) in Africa
• focus on combined effects of different processes of global change
• advance the design of such policies to be appropriate for the most
vulnerable groups
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Global food security policies
Locally installed instruments to enhance food security
Environmental
instruments
Land policies
instruments
Instruments to
cope with risk
Combined effects of global change (e.g. climate change,
demographic change, environmental change)
Other land
user
Pastora-
list
Pastora-
list
Natural
resources
LocalSystem1Morocco,2Ethiopia/Kenya
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5/18
Methodological approach
• Social-ecological modelling
Agent-based modelling
• Modelling human decisions
• Social network analysis
1 POLISES| 2 METHODS | 3 THREE MODELLING STUDIES| 4 FURTHER IDEAS

Methodological approach:
Social-ecological modelling
1. Exploration of behaviour of social-ecological system
in time and space
2. Including the feedbacks between the social and
ecological components and understand mechanistic
functioning
3. Virtual lab: Systematic analysis of combined effects
of global change processes (turn processes on/off)
 Stylized model / “Toy model”
4. Behaviour of land users can be modelled more
realistically: adaptation, interaction, learning
Rule-based simulation models
Agent-based
model
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Our modelling strategy: Start with simple model and add
complexity step by step
Decision criteria /
strategy choice
Social-ecological system
Climate
Precipitation
Institutions
Insurances /
Access regimes / …
Technologies
Trucks /
Fodder supplements /…
Livestock
Sheep
Agents
Pastoralist households
Vegetation
Ecological Model
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Ecological submodel
Climate
Vegetation
precipitation
lognormal distribution
Livestock Sheep
green
biomass
reserve
biomass
growth
rain / grazing history
feeding reproduction
forage
grazing
currentrainfall
Ecological-economic study:
Role of resting in rainy years
• Natural insurance
• Investment in the future
Müller et al. 2007 Agricultural Systems
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Fair insurance
i - Payment of insurance
b - Insurance prime
p* - Strike level of insurance
z.B. wenn Regen unter 75%
des langjährigen Mittels fällt
Without insurance
With insurance
Optimalfractionofrestingαin%
strike-level of the insurance in % of MAP
Results:
1. The higher the strike level
… the less resting
… the lower the sustainability in the
long-term
Müller et al. 2011, Ecological Economics
2. If strike level low enough:
Unintended side-effects avoided
if
if
Study 1: (Side) effects of index-insurances
One agent, homogeneous pasture
Decision rules:
Expected utility
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Study 2 - Polarisation: Multi-agent model
• Inspired by Moroccan case
study
• Temporal structure: Discrete,
yearly time steps,
time horizon = 100 years
• Spatial structure: patch
network on a hexagonal grid
• Dynamic feedback between
ecological and economic
component
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Study 2 – Polarisation: Approach
Diploma Thesis: Falk Hoffmann
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Stepwise add types of heterogeneity
0. Homogeneous rainfall
1. Spatial heterogeneous rainfall
Agent heterogeneity:
2. High / low mobility agents
(low costs / high costs)
3. Plus different initial herd size
4. Plus different initial cash savings
D. Kreuer

Study 2 - Polarisation: Results & Next steps
Case 1: If vegetation resilient
Initial conditions of agents differ + different mobility
costs
No
polarisation
Polarisation
Case 2: If vegetation less resilient
Combined effect of heterogeneous mobility costs
+ Heterogeneous initial herd sizes
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Currently carried out: Systematic sensitivity analysis
Next step: Investigate measures against polarisation

Study 3: Multi-agent model on pastoral land
use of Borana – Pastoralists
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Central village patch
Permanent
remote patch
Dry season Rainy season
Herd movement
Once per season
(4 seasons per year)
Dry season, if
rain sufficient
Temporary
remote patch
In cooperation with Russell Toth

Study 3: Multi-agent model on pastoral
land use of Borana – Pastoralists
14/18
Model
reproduces
boom and bust
cycles of herd
sizes
1 POLISES| 2 METHODS | 3 THREE MODELLING STUDIES| 4 FURTHER IDEAS
First version of
index-insurance
implemented

Study 3: Research questions for Borana model
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1. Under what conditions is mobile pastoralism
sustainable, in the absence of insurance?
2. How does the uptake of insurance influence
livestock numbers and vegetation conditions
over the long term?
3. How does the design of the insurance
influence uptake, and therewith the livestock
numbers and vegetation conditions ?
4. What is the impact of change of weather
conditions ( climate change) on these
outcomes?
5. What is the impact of other institutional
changes – e.g., land use restrictions?
R. Toth

Further research topics for collaboration
1. Crowding out of social networks
by microinsurances
Abstract model: Use of social network analysis
coupled with multi-agent model of pastoral
system
2. Educational games:
Board game NomadSed
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NomadSed: A board game on sustainable land use
of mobile pastoralists under global change
1. Educational purposes
• Insights in coupling
environment & livelihood
• Challenges of nomadic life
2. Science-society interface
Use of the game:
In cooperation with Vétérinaires sans Frontières Germany
Project days in schools
„Long night of sciences“
Exhibition at museum
University education
(national & international)
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Key messages
Use of stylized models not for prediction
as tool for thinking, interdisciplinary communication and hypothesis testing:
• Rise awareness of unintended side effects
• Inspire discussions with policy makers, insurers, scientists and other
stakeholders
• Advice: If new policy instruments are designed – monitor impact on land use
strategies
Use of agent-based models:
• Include human-decision making in more realistic way than standard
economic approaches incorporation of social learning, diffusion of
innovations
• Explicit incorporation of feedbacks between socio-economic and ecological
system components
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Thanks for your attention
And to cooperation partners:
Russell Toth (University of Sydney)
Brigitte Kaufmann (German Institute for Tropical and Subtropical
Agriculture)
Mohamed Mahdi (École Nationale d‘ Agriculture Meknès,
Morocco)
More information: www.polises.de