Models of farms and their application

Daniel Rodriguez

A complex system

Rodriguez and Sadras, 2011

Household surveys and typologies, interviews, and discussion groups

Uncertainties (unknowns)

Understanding vulnerabilities: identifying priorities and options

Human dimensions

Strategic: Sensitivity and scenario analyses, use of downscaled GCMs

Increased preparedness, increased resilience and profitability

Risks (known unknowns)

Household ModellingFor the sustainable intensification of agriculture

Tactical: What if? Improved risk management through the relevant use of forecasting tools

Diagnosis and evaluation

Social desirability

Ex-ante understanding, impacts, performances & trade offs

Sup

port

ing

impl

emen

tatio

n Describe, current production systems and

their problems

Explain, current farmer’s decision on resource allocation and their

consequences

Explore, options for agro-technological

improvement in face of possible future scenarios

Design, new management systems

that contribute to increasing resilience and profitability in agriculture

Participatory whole farm modelling

Dynamic

Variable environment

Representing complex systems

Acceptance Functional

State contingent

EmpiricalStatic

Deterministic Stochastic

OptimisationLinear

programing

Evolutionary approaches

Expert knowledge

What if? questions

Scenario and sensitivity analyses

Data availability / level of ignorance

“…In my judgment, farmers' decisions made in this ad hoc way are usually very good. They are not perfect (farmers

are human!) but they are usually near enough…” David Pannell

How optimum is optimum enough?

So, what is the fuss about optimization?

Objective 1

Objective 2

Trade-offs

• Practices• Tillage & ground cover• Moisture seeking

• Tactics• Planting rules• Soil water thresholds• Crop sequences & intensity• Long fallowing• Forage conservation

• Strategies• Crop selection (winter / summer)• Water allocations• Land allocations• Cropping / grazing mix

• Farmers’ preference• Risk preference & its trade offs• Plastic vs rigid

Alternative farming systems

Less of 2

More of 1 More of both

Thanks