Land use changes affect hydrological ecosystem services in Madagascar. Researchers studied the impacts of different land uses - closed canopy forest, reforested tree fallow, shrub savoka (shrub fallow), and degraded land - on streamflow. They found infiltration rates were lowest and surface runoff highest on degraded land. Reforestation increased infiltration and decreased runoff. The researchers engaged with local communities and policymakers to communicate these findings and promote sustainable land use decisions that protect livelihoods.

1. The impacts of land uses change on
hydrological ecosystem services:
communicating facts for sustainable
land use
Maafaka Ravelona

2. Presented by:
Maafaka Ravelona
mr667@cam.ac.uk
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Co‐authors:
Chandra Prasad Ghimire Bob W. Zwartendijk
Ilja van Meerveld Jaona Lahitiana
Julia Jones Herintsitohaina Razakamanarivo

3. Presentation Overview
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1. p4ges project
2. Context in Madagascar
3. Hydrological research
4. Engaging the community & policy makers
5. Conclusion

4. P4ges seeks poverty alleviation
through ecosystem services
Biophysical integrated data
collection:
 Closed canopy forest
 Tree savoka (Tree fallow)
 Shrub savoka (Shrurb fallow)
 Tany maty (degraded land)
 (Reforestation)
CC RF SA TM
 Hydrology
 Biodiversity
 Carbon

5. Streamflow affects our daily lives
low flow periods
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irrigation
Hydropower
fishingDomestic water use

6. Streamflow affects our daily lives
flooding
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7. Local and regional water resources: Our daily reality
▪ Too much water – flooding and loss of crops
▪ Too little water – not enough water for irrigation and rice production
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8. Land use affects local and regional water
resources
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What happens here…
…affects what happens
here

9. P4GES Hydrological Research: Objective
▪ To determine hydrological impacts of land‐use changes on dry
season flows

10. Hydrological research: Hypotheses
1. Land degradation leads to more surface runoff, higher peak
flows and lower dry season flows
2. Reforestation can reverse this trend

11. Landscape scale measurements
▪ Soil properties: texture & structure
▪ Soil infiltration rates (at 3 depths)
▪ Preferential flow pathways

12. CC
RF
SA
TM
Infiltration results
DLSS/TS

13. Blue dye experiment
to determine how water flows into the soil
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14. Dye experiments
Reforestation
Degraded land

15. Plot scale measurements
Three plots (forest, tree fallow and degraded land):
▪ Hydrological fluxes (precipitation, interception,
transpiration, surface runoff)
▪ Changes in soil moisture and groundwater

16. Weather stations
Determine evaporation and precipitation rates
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Rain gauges
Temperature and
relative humidity
Solar panel
Radiation
Data logger

17. Runoff plots
Determine how much water flows over the surface
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18. Surface runoff 1 year period:
Oct 2014‐Sep 2015
degraded closed canopy forestreforested tree fallow
1650 mm 1630 mm 1750 mm
180 mm 35 mm 25 mm
11% 2.1% 2%

19. Additional measurements in forest
Rainfall measurements under the forest canopy
Measurements of tree water use
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66‐collectors3‐gutters

20. Throughfall: Nov 2014‐May 2015
degraded closed canopy forestreforested tree fallow
1650mm 1337mm 1270mm
100% 82.3% 73%
1650 mm 1630 mm 1750 mm
102 mm
6.3 %
1235 mm
76 %
30 mm
2 %
1240 mm
71 %

21. Fieldwork summary
Results suggests that
▪ Infiltration rates are lowest under degraded land and increase
after reforestation or natural regeneration to tree fallow
▪ Surface runoff is highest for degraded land and lower for
reforestation and forest sites
▪ Differences in interception losses between forest and
reforestation sites are small

22. Researcher and local workers
explaining their observations
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23. Engaging the community
‐ Strong partnership with Mitsinjo
Association (facilitated work on 2 field
sites owned by the Association)
‐ Capacity building, including training and
in field experience
‐ Strong cooperation with local workers
‐ Local project ownership, participation,
discussion and feedback on results and
impacts on livelihoods
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24. Engaging the local community
▪ How can we help them make good decisions around land use?
▪ First step: communicating and explaining the project results
▪ Understanding how results impact their daily life and supporting
communication between neighbours
▪ Same language
▪ Same perception
▪ Same status
▪ Encourage feedback to P4ges
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25. Engaging
policy makers
▪ Events (including field visits) to showcase the measurements
and the results
▪ Facilitated national /regional media opportunities
▪ Asked for impressions, feedback and likely land use change
scenarios.
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“This work is extremely interesting and it is so good to visit it and see the equipment
in the field. If you just watch a presentation you don’t get the full understanding”
Dimby Razafimpahanana ‐ Rebioma
“…our wish is that the final report of this project won’t just fill the scientific shelves
but will be communicated to the local people and have a real sustainable impact on
their livelihood, indeed for poverty alleviation”.
Former President of Mitsinjo Association.

26. ▪ A better understanding of the result stimulates local
solutions and empowers communities to make decisions
that affect their livelihoods.
▪ Beyond local communities, we need to communicate the
research results to policy makers.
▪ Next step: December 2015 ‐ Restitution led by the local
workers to:
‐ further showcase the results
‐ share knowledge to promote understanding of the
effects of land use decision.
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In conclusion

27. ACKNOWLEDGMENTS
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