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On Landslides, Ecosystems and
UNU-EHS, Bonn, 2010
On Landslides, Ecosystems and Livelihoods
Sudmeier-Rieux, K.
University of Lausanne,
- Institute of Geomatics and Risk Analysis
IUCN Commission on Ecosystem Management
Outline
(i) To review the latest scientific developments and working hypotheses with respect to ecosystems, ecosystem services and DRR
(ii) To review the latest tools and methods used for linking ecosystem management and DRR
(iii) What is the contribution of ecosystem services and their management towards vulnerability and disaster risk reduction and livelihood resilience enhancement? and livelihood resilience enhancement?
(iv) How could these services be measured (development of tools and methods) and how could this be translated for practitioners (or in user-friendly applications)?
(v) To identify key research gaps that remain to be addressed when addressing the role of ecosystem, ecosystem services and DRR
1. Science tools and methods 2. Ecosystem services 3. Measuring services 4. Gaps and conclusions
Landslide world trends
Hydro-meteorological hazards, ISDR, 2009
1. Science tools and methods 2. Ecosystem services 3. Measuring services 4. Gaps and conclusions
Landslide world trends
• Annual fatalities around
5000 per year
• Small shallow landslides
underreported >> livelihoods
•Small cumulative events
•Ridge to reef > siltation
Worldwide mid-sized events
Petley, 2005
•Ridge to reef > siltation
• More intense rainfall
patterns and esp. more
exposed pop’s >> increase in
landslides
• Most occur in SE Asia and
Central America
1. Science tools and methods 2. Ecosystem services 3. Measuring services 4. Gaps and conclusions
Types of landslides
Slides
Flows
Falls and topples
Subsidence
Rock avalanches or
failuresGlade and Crozier, 2005
1. Science tools and methods 2. Ecosystem services 3. Measuring services 4. Gaps and conclusions
Factors causing landslides
Preparatory factors:
•Rainfall > soil
moisture
•Deforestation
•Grazing
•Road construction
•Slash and burn
Triggering factors:
•Rainfall thresholds>
locally specific
•Earthquakes
•Road
construction/blasting
•Slash and burn
1. Science tools and methods 2. Ecosystem services 3. Measuring services 4. Gaps and conclusions
Shallow landslides < 1 meter deep
Rainfall triggered landslides in
New Zealand, 2004,
Crozier and Glade, 2005
Earthquake triggered landslides in
Kashmir, Pakistan, 2006,
Sudmeier-Rieux, 2006
1. Science tools and methods 2. Ecosystem services 3. Measuring services 4. Gaps and conclusions
Deep seated landslides > 1 meter deep
Rainfall-induced rockslide,
New Zealand, 2004
Crozier and Glade, 2005
Earthquake-induced rockslide,
Kashmir, Pakistan, 2006
Sudmeier-Rieux, 2006
1. Science tools and methods 2. Ecosystem services 3. Measuring services 4. Gaps and conclusions
Vegetation and landslide stability
1. Science tools and methods 2. Ecosystem services 3. Measuring services 4. Gaps and conclusions
Vegetation cover and landslides, Mexico
•Based on
remote sensing
study in Sierra
Norte
•Vegetation
changes 1989-
Alcantara-Ayala, 2006
1. Science tools and methods 2. Ecosystem services 3. Measuring services 4. Gaps and conclusions
changes 1989-
1999 (-70%)
•Heavy rainfall in
October 1999
•Massive
landslides on
barren soils
Vegetation cover and landslides, Pakistan
•100 landslides profiled
•17 km 2 surface area
•84 landslides on right
bank
•Vegetation cover
highly degraded highly degraded
•56% grazing, followed
by roads
•Similar geology and
slope gradient (50-55°)•Private ownership vs.
state regulated
•Remote sensing,
ground truthing
Ecosystems, livelihoods and landslides
• Livelihoods in mountain areas depend on delicate human-environment interactions
• Landslides both create favorable conditions for human activity and destroy them
• « Proper » terracing can • « Proper » terracing can stabilize slopes: rainfed agriculture vs. irrigated fields?
• Road building, excavation, deforestation can lead to slope destabilization
• Trade-offs between improved access and landslide risk
1. Science tools and methods 2. Ecosystem services 3. Measuring services 4. Gaps and conclusions
Contribution of ecosystems to DRR
Swiss Alps/ Dorren, 2007
1. Science tools and methods 2. Ecosystem services 3. Measuring services 4. Gaps and conclusions
Protection forests in Switzerland
• Forests are estimated to save between US$ 2–3.5 billion per year in disaster damage
• Cost effective slope stabilization stabilization
• Forests managed as multi-age stands
• Other benefits such as aesthetics and firewood
Andermatt, Switzerland
1. Science tools and methods 2. Ecosystem services 3. Measuring services 4. Gaps and conclusions
Locally adapted slope stabilization
French alps/ Dorren, 2007
1. Science tools and methods 2. Ecosystem services 3. Measuring services 4. Gaps and conclusions
Locally adapted slope stabilization
Pakistan/ Sudmeier-Rieux, 2006
1. Science tools and methods 2. Ecosystem services 3. Measuring services 4. Gaps and conclusions
Measuring ecosystem services & reducing risk
• Few economic valuation studies to measure value of vegetation cover for landslide risk reduction
• Landslide risk management is traditionally hazard- rather than vulnerability and risk focused
• Slope stabilization – from highly costly to locally adapted
• « Top-down » remote sensing using satellite images SAR • « Top-down » remote sensing using satellite images SAR (Synthetic Apeture Radar), GIS
• « Bottom-up » participatory risk mapping, 3D GIS methods
• Community based monitoring
• Community based risk/resilience index
• Risk Vulnerabilty Assessment Methods Project (RiVAMP) (UNEP)
1. Science tools and methods 2. Ecosystem services 3. Measuring services 4. Gaps and conclusions
Research gaps
• Vegetation and soil erosion link well documented BUT more on thresholds needed AND role of human impacts on landslides HOWEVER often locally specific
• Not many economic valuation studies that demonstrate the value of forests to DRR
(+ livelihood benefits?)
>>> policy implicationsNepal / Sudmeier-Rieux, 2009
1. Science tools and methods 2. Ecosystem services 3. Measuring services 4. Gaps and conclusions
Conclusions
• Methods usually include remote sensing, geological studies w. ground verification > pros and cons
• Reducing landslide risk depends on amount of risk a society is willing to accept and $ means available
• Locally-adapted methods for monitoring and landslide
• Locally-adapted methods for monitoring and landslide reduction through community based DRR
• Research – community -policy gap
• Multiple uses – landslide mitigation and livelihood support (e.g. bamboo) Nepal/ Sudmeier-Rieux, 2009
1. Science tools and methods 2. Ecosystem services 3. Measuring services 4. Gaps and conclusions
FEEDBACK WELCOME - THANK YOU !
Thank you:
University of Lausanne,
Institute of Geomatics
and Risk Analysis
International Union for
the Conservation of the Conservation of
Nature (IUCN)
Commission on
Ecosystem Management
Funding from:
Swiss National Science
Foundation 2009-2011
