Presented by Dr. Randall Ritzema (IWMI) at the Nile BDC Symposium on Modeling in the Blue Nile Basin, Addis Ababa, 12 November 2012

1. Integrating Biophysical and
Socioeconomic Model Outputs
Dr. Randall Ritzema
IWMI
Nile BDC Symposium on Modeling in the Blue Nile Basin
Addis Ababa, 12 November 2012

2. Background
• Goal of Nile Basin Development Challenge Project 4 (N4) is to
assess potential impacts- both biophysical and
socioeconomic- at the basin scale resulting from
implementation of Rainwater Management Strategies
• To assess impacts, need to link biophysical and socioeconomic
processes
• Modeling has proceeded along disciplinary lines, and at
differing scales:
– Hydrologic: SWAT, APEX
– Water resource management: WEAP
– Economic: ECOSAUT
– Crop: CropWat, AquaCrop
– Livestock: ILRI livestock water productivity model
• This presentation: initial ideas on model integration

3. Basin-level BP/SE integration frameworks
Sectoral Linkage Explicit Integration
To link and extrapolate BP and SE processes
Resource Management Typology

4. Resource Management Typology
• Delineate population segment which manages BP resources in
target catchment
• Partition population segment into RM units
– Assumption: Economic decisions made at HH level
– Livelihood Profiles suggest different HH production systems w/i
Livelihood Zones
– HH’s can therefore be aggregated into RMUs based on BP and SE
attribute similarities
– Assumption: Access/benefit/cost is equitably distributed within RMU
• Water/Land “management” mapping- establish BP resource
flows from/to RMUs

5. Resource Management
Typology
• FEWSNET/LIU
Livelihood
Zones/Profiles:
natural RMU
definitions
• Ethiopian Rural
Economic Atlas:
population/HH
distributions
• Full spatial /
economic coverage:
satisfies need for
extrapolation

6. Sectoral Linkage Approach: BP-initiated
BP Tools
N3 Feasibility
SWAT AquaCROP
Mapping
HDM via
RMUs
Flows ( ECOSAUT)
(unimpaired)
Considerations:
•Potential of fragmented WEAP
linkages
•Use of MCA to understand
interactions
•Feedbacks?
Flows SE Impact
Sediment
(impaired) Indicators

7. Sectoral Linkage Approach: SE initiated
Verification of
assumptions?
Expected yield &
BP Tools
water use
Other econ inputs
Apex-
verified AquaCROP
SWAT
RMU HDM: RMU Land SISM
charac- (modified DDM use to (modified
terization ECOSAUT) HRU’s Flows Irrigation HDM)
(unimpaired) Demand
Carry-over water
availability
WEAP
Considerations:
•Use of N3 mapping to constrain RMU
decision-making SE Impact
Flows
•One “optimal” decision set per set of imposed Sediment
(impaired) Indicators
conditions
•Feedbacks?

8. Explicit Integration Approach
N3 Feasibility
Mapping
Systems Dynamics integrated model
Apex- Flow/sediment response
verified module characterization
SWAT (subcatchment)
RMU
charac-
terization
Crop response / irrigation
AquaCROP demand module
characterization
Considerations:
•Feedbacks embedded; addresses fragmented linkages
•Potential to assess many scenarios, uncertainty
SE Impact
•Depends upon effective modules Sediment Flows
Indicators