PIER : Protection, Ecological Engineering and Restoration

The PIER team's research concentrates on the sustainable management of hazard prevention measures. These measures relate to both natural hazards caused by gravitational movements (rockfalls, landslides and avalanches) and erosion hazards, against which vegetation and its adaptive management are able to provide effective and sustainable mitigation. The team's main objective is to support risk prevention policies in the context of global change and to ensure the sustainability of systems and territories. One of the main scientific challenges in this area is mobilizing the knowledge gained in order to model current and future risks, including those on a regional scale. Our research is driven by society's demand for improved natural hazard prevention, by taking better account of the functions offered by terrestrial ecosystems in strategies for sustainable territorial development.


The PIER team seeks to address three key research topics:

  • The generation of knowledge through the qualitative and quantitative assessment of interactions between terrestrial ecosystems and natural hazards (rockfalls, avalanches, landslides and erosion).
  • The formalization of this knowledge into models for characterizing the mechanical and ecological behavior of the various ecosystem components studied, at different organizational levels and geographic scales.
  • The development of management and assessment tools, both scientific and technical, for predicting 1) hazards (their creation and/or propagation), by integrating ecosystem responses, and 2) risks, by integrating human vulnerabilities. These tools should help guide strategic choices and intervention approaches, particularly in relation to the design of structures (guides), and the testing of various options for mitigating these risks using ecosystems, by integrating their natural or impacted dynamics (models).

Management applications

Researchers are working closely together, both domestically and internationally, with various public and private stakeholders (ministries, forestry services, research centers, industry associations, consultants, etc.), on the implementation of policies relating to natural risk prevention and/or management of terrestrial ecosystems. The recognition of the protective function performed by terrestrial ecosystems in territorial ecosystem planning and management documents is the primary framework for the operational application of our results. In addition to the composition of scientific and technical publications, our support and transfer activities are particularly relevant to:

  • The production of guidelines and practices for preventing torrential erosion by using bioengineering or management of forests for protection
  • Protective forest zoning
  • Transfer of our models for training purposes
  • The undertaking of assessments
  • Diagnosis to support mountain wood mobilization


Resources and techniques implemented

  • In situ and ex situ experiments to study and model the mechanical resistance of trees when struck by a rocky projectile and the spread of rockfalls (Vaujany experimental site)
  • In situ experiments to characterize the effect of various bioengineering works as means of preventing soil erosion (Draix, Durance Plan)
  • Monitoring of cable logging operations
  • Drone snapshots and image analysis
  • Establishment of forest monitoring sites (marteloscopes, reference plots for the analysis of LiDAR data, tree mapping and dendrometric inventories)
  • 2D and 3D modeling of the spread of rock projectiles with and/or without taking into account the effect of forest vegetation

Research areas

  • The use of dendrogeomorphology to determine the nature of previous spatio-temporal activity in landslides, avalanches and rockfalls
  • The integration of tree and forest stand actions and bioengineering works into simulation models of the propagation of natural risks
  • LiDAR Remote Sensing: Identification and characterization of forest stands and forest biomass
  • The development of a methodology and associated tools for the departmental spatial planning of forests as a protective measure
  • Sylvaccess: A model for automatically mapping the accessibility of mountain forests
  • EcorisQ: Having contributed to its creation in 2008, the team is a member of EcorisQ, the international association of experts in forest-based protection against rockfalls, avalanches and landslides. Its main objective is to promote forest engineering risk prevention and assessment models (RockforNET, Rockyfor3D)
  • Innovative use of ecological engineering works to control erosion and sedimentation

Ongoing projects

  • Durance Plan: Study on the innovative use of bioengineering to control erosion and sedimentation in the catchment areas of the Durance and Bouinenc rivers
  • AGéBio: The French bioengineering association for the control of soil erosion
  • Catars: Characterization of the architectural traits of plant root systems involved in soil stabilization processes
  • FORESEE: Characterization of forest resources for bioenergy (ANR Bioenergy 2010, 2010-2014)
  • SAMCO: Societal adaptation to mountain risks in a context of global change (ANR SOC&ENV 2012, 2013-2016)
  • ARANGE: Advanced multifunctional forest management in European mountain ranges (FP7-KBBE, 2011-2014)
  • NEWFOR (coordination): NEW technologies for a better mountain FORest timber mobilization (Interreg Espace Alpin, 2011-2014)
  • ASPIRE: Assessment of the success of engineering projects and environmental restoration

Recent projects

  • FORGECO: From diagnosis to action: towards an integrated and sustainable management of forest ecosystems within territories (ANR Systerra, 2010-2014)
  • IFP: Interreg Protective Forests project (Interreg F-Switzerland and F-Italy, 2007-2013)
  • MANFRED: Management Strategies to Adapt Alpine Space Forests to Climate Change Risks (Interreg Espace Alpin, 2007-2013).
  • PARAMOUNT: imProved Accessibility: Reliability and safety of Alpine transport infrastructure related to MOUNtainous hazards in a changing climate (Interreg Espace Alpin, 2007-2013).
  • Irstea-OFEV Agreement (Switzerland): Evaluation of the effect of alternative "minor works" strategies to protect against rockfalls by using forest residues. Measuring the length of regeneration gaps in rockfall areas. (OFEV - Switzerland, 2011-2014)
  • MO-sols : Biological activation of the soil by adding organic matter to areas subject to heavy erosion and climate constraints

Ongoing PhDs

  • Ignacio Olmedo-Manich (2015). Experimental and numerical study on the effectiveness of timber operations as a natural protection against rockfalls (supervisor Franck Bourrier)
  • David Toe (2015). Study of the influence of forest coppice plantations on the spread of boulders (supervisor Frédéric Berger).
  • Jean-Baptiste Barré (2016). Characterization of the mechanical biodegradation of a wooden rod as a component in ecological engineering works protecting against natural hazards (supervisor Freddy Rey).
  • Sylvain Dupire (2017) Establishing a balance between protection against rockfalls and resistance to fire in mountain forests: what vulnerability for mountain areas? (supervisor: Frédéric Berger)

Recent PhDs

  • Amandine Erktan (2013) The role of the functional composition of plant communities in ravine bed ecosystems undergoing ecological restoration (supervisor Freddy Rey).
  • Christophe Bigot (2014). Modeling the loss of mechanical resistance in forest residues based on the decomposition of woody biomass (supervisor Frédéric Berger).

Team composition

Organization Technicians, engineers, researchers

PhD students, post-doctoral researchers

Frédéric Berger (PhD)

Catherine Lukie

Geneviève Nouvellon

Nicole Sardat

Laurent Borgniet (PhD)
Franck Bourrier (PhD)
Jordan Fèvre
Renaud Jaunatre (PhD)
Jérôme Lopez-Saez (PhD)
Eric Mermin
Freddy Rey (PhD, HDR)
Rémy Rosamont
Pascal Tardif
Jean-Baptiste Barré
Ignacio Olmedo-Manich
David Toe