Benoît Courbaud (CEMAGREF Grenoble, Mountain ecosystems)
Thomas Cordonnier (CEMAGREF Grenoble, Mountain ecosystems)
Ongoing and past projects
PhD thesis (2010-2013), CEMAGREF Grenoble - Joseph Fourier University:
Production-biodiversity and silviculture compromises of heterogeneous mountain populations:
Analysis of forestry itineraries using simulations
Global changes and developments in the current socio-economic environment reinforce expectations for multi-functional forest management, combining production and protection of biodiversity. Mountain forest populations benefit from a long tradition of silviculture for irregular populations, specifically in relation to beech-fir-spruce plantations. New requirements to "produce more while preserving better" nevertheless require scientific justification and a renewal of silvicultural itineraries. Forest managers are clearly willing to “intensify forestry” (diminishing growing stock, diminishing exploitable diameters, reduced thinning to improve populations). It is necessary to evaluate in what way these developments are compatible with sustainable forest management, ensuring production and preserving biodiversity over the long term. The context of global climate change makes predictions more difficult and means that climate and seasonal changes must be taken into account during this analysis.
It is difficult to anticipate the long-term influence of new forestry strategies based only on an analysis of past management techniques. Simulation work already carried out with bitmap models of forest dynamics have provided initial results that are less bound by the past than direct observation. However, the structure of these models limits the types of forestry that can be tested. The use of individually centred spatial models such as those developed in the Research Unit will enable the effects of forestry and seasons on the sustainability of forest functions to be explored much more fluidly. Exploitation of these more complex usage models still requires the implementation of a complete range of simulation and analysis experiments.
The aim of this thesis is to define the conditions for sustainable forestry of heterogeneous populations of beech, fir, spruce and associated species while responding to production and biodiversity preservation constraints. Work will focus on two general hypotheses: (1) that an intermediate intensity of forestry would allow sustainable compromise between biodiversity; (2) that biodiversity facilitates the forestry of heterogeneous populations by enhancing their resistance and resilience when faced with upheaval (anthropic or natural).
Work will be based on the use of the Samsara2 simulation model developed by CEMAGREF for mountain fir-spruce groves and a new version that includes more species and integrates the effects of climate and season. The proposed experimental methodology includes phases for model evaluation, definition of control and response variables, sensitivity and response surface analysis, results summaries and relevant method selection to carry out field experiments. The concept of ecosystem vulnerability and resilience will be further studied to propose indicators allowing the sustainability of the production-biodiversity compromise to be evaluated based on the temporal variation of responses studied.
The thesis will run within a larger project developed as a partnership between CEMAGREF (Mountain Ecosystems RU and Forest Ecosystems RU) and the French National Forest Office (Technical Department and Jura TU). The project, titled “Producing more while better preserving biodiversity: which multifunctional management method for heterogeneous forest populations?”, will be funded by the MEEDDM (Ministry of Ecology, Energy, Sustainable Development and the Sea) and MAAP (Ministry of Food, Agriculture and Fishing) Biodiversity, Forest Management and Public Policy programmes
Lafond, V., Cordonnier, T., de Coligny, F., and Courbaud, B. (2011) Reconstructing harvesting diameter distribution from aggregate data. Annals of Forest Science. In Press, online first on december 2011.
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