Transcript in Guadiana river basin

Diversification to adapt to
climate change
(in Guadiana river basin)
 Saskia Werners, Wageningen University & Research Centre, NL
 F. Incerti, M. Bindi, M. Moriondo, University of Florence, IT
 Francesc Cots, Universitat Autonoma de Barcelona, ES
Conclusion: Adaptation is inevitable. The climate is inherently
uncertain. Adaptation requires a risk management approach.
Diversification of activities (here: crops) can reduce climate
related risks.
Presentation
• Why this study: How to live with change and reduce
climate related risks
• Where: The Guadiana river basin, Spain/Portugal
• How: Crop modelling, regional climate scenarios and
risk assessment
• What: Results
• Now what: Conclusions & future work
Background: the ADAM project
•
ADaptation And Mitigation Strategies: Supporting climate policy
•
www.adamproject.eu
•
Supported by the European Commission, 6th Framework program of
the Research Directorate
•
25 partners in Europe & outside, incl Chinese Academy of Sciences
•
Research on Mitigation, Adaptation, scenarios and policy appraisal
•
Three regional case studies: Guadiana river in Spain/Portugal-EU,
Alxa region in Inner Mongolia-China & Tisza river, Hungary-EU
•
A first workshop and fieldtrip to the Alxa region will be held later this
week. Please contact me if you want to exchange info.
Why this study?
Goal:
•
How to adapt to an uncertain climate?
This study: Find land use/crop patterns that reduce climate risks
•
Diversification suggested in various fields as a means to become
resilient, cope with shocks (agriculture, ecology, economics)
•
Study diversification (here: combining different agricultural crops) as
adaptation strategy (here: to stabilise farmer income)
•
Here we define: risk = variance in farmers’ income
(less variance -> better adapted)
•
Future: To extend this example to other land and water uses
Why: Gaudiana river
Where: Gaudiana
Water
Waterecosystem
ecosystem
Industry
Tourism
One of largest basins of Iberian Peninsula, transboundary Portugal - Spain
Water consumption is polarised by farming needs (60%), industrial activities (24%) and
domestic water supply. Spain (81%), Portugal (19%)
Semi arid climate , Strong seasonal variations and periods of drought
Main sources of pollution: agricultural, industrial activities and urbanisation.
Salinisation problems. River heavily regulated. Alqueva dam and lake.
Richness of natural and cultural heritage, incl traditional ‘dehesa’ landscape
Where: Gaudiana
Mertola
Alqueva lake
How: crop model, climate model, risk
Simulate crop yields (barley, sunflower, durum wheat, sorghum, maize)
with CropSyst (Cropping Systems Simulation Model) specifying a.o.
soil properties, fertilizer, irrigation, CO2 concentrat.
Simulate for climate scenario baseline years 1961-1990;
Future climate scenario: A2 2071-2100. Daily data regional climate
model HIRHAM, 12.5km grid resolution (PRUDENCE project)
Crop revenue: Mean annual revenue earned from the crops over a 30 year
simulation period (gross revenue: price times yield per acre)
Risk: variance of revenue of cropping pattern (mix of crops) in area (grid
cell) over 30 years (1961-90 or 2071-2100)
Aim: find cropping pattern with lowest risk or best revenue risk ratio
(similar to portfolio management in investing)
Results: crop revenue
Average crop revenue ± standard deviation of cropping patterns with
different shares of sunflower versus barley
Revenue Sunflower Barley
[euro/ha]
Cropping
Best revenue-risk
pattern MinVar cropping pattern*
Base:
1961-1990
227 ± 113
276 ± 122 231 ± 90 (share
sunflower 0.78)
246 ± 96 (share
sunflower 0.53)
A2:
2071-2100
236 ± 101
278 ± 108 245 ± 90 (share
sunflower 0.71)
262 ± 96 (share
sunflower 0.36)
Correlation: sunflower-barley: 0.57 (1961-1990) -> 0.71 (2071-2100)
*) the optimal combination of risky investments (or Tangent Portfolio in
Modern Portfolio Theory)
Cartoon: mixing two crops in Gaudiana basin
Scenario baseline years 1961-1990;
Climate scenario A2 2071-2100
Share barley for lowest risk (variance) in total crop revenue
Share barley for best revenue – risk (var.) ratio for total crop revenue
Lessons & Conclusions
•
Word of caution: Analysis & previous figure do NOT include all
relevant crops + land uses. Assessment crop revenue very simple; e.g.
subsidies not included. Crop selection not only for adaptation.
•
Risk is not (only) snapshot. For adaptation you have to take into
account a range of climate conditions and how these conditions
impact your activities.
•
Diversification can reduce risk depending on local situation. Given
your activities and the climate conditions, there is an upper limit to
diversification beyond which risks cannot be ‘diversified away’.
•
Climate change modifies (co)variance of crops (less yields). Reevaluation of cropping patterns can provide higher risk security.
Thanks! & Discussion
Grasses in Antarctica
Crops in Ethiopia
Contact: [email protected]
Info: www.adamproject.eu
Now what?
•
Check crop yields (model, against statistics)
•
Check climate scenarios & how typical time period is (ADAM S)
•
Improve methodology
•
Include other crops & other land uses
•
Test in other regions
•
Reconstruct &compare to historic/spatial profile of diversification
•
Discuss what determines current land use & land use change
Portfolio management
•
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