Sustainable fuel wood production and wood ash recycling on acidic forest soils

Vincent Boulanger (1) , Christine Deleuze (1) , Gwénaëlle Gibaud (1) , Noémie Pousse (1) , Claudine Richter (1) , Alain Berthelot (2) , Isabelle Bertrand (3) , Jacques Ranger (4) , Laurent Saint-André (4)

1 Département R&D
2 Délégation territoriale Nord-Est
3 FARE - Fractionnement des AgroRessources et Environnement
4 BEF - Unité de recherche Biogéochimie des Ecosystèmes Forestiers

Fuel wood is a critical component of the sustainable French energy development plan. To anticipate the demand, foresters have to consider innovative silvicultures that ensure an increased and sustainable biomass supply. On fertile agricultural soils, biomass-dedicated plantations proved efficient. Their transposition on more acidic forest soils requires studies targeting soil chemical and physical fertility management, adapted tree species selection, silvicultural developments adaptation along with assessments of both technical feasibility, economic efficiency and short- to long-term ecosystem impacts. These developments suppose focused experiments on planting techniques (soil preparation and liming), a prerequisite for enhancing productivity. An 11 ha experiment was initiated in the French Ardennes by a partnership between FCBA, INRA and ONF. It compares the effects of various soil mechanical preparation and fertility management techniques on the productivity of biomass-dedicated (hardwood) and semi-dedicated (coniferous) silvicultures. More specifically, we tested the use of wood ash from heating plants for soil protective liming, one option for a closed-loop and sustainable forest soil fertility management. In order to establish a baseline for long-term ecosystem monitoring, just after tree plantation (in 2013) soil from the 48 experimental plots was sampled and measured for chemical properties, and ground flora was surveyed on a subset of 30 experimental plots, crossing soil-preparation technique (deep or superficial soil decompaction), liming type (none, commercial or wood ash/dolomite mixture) and two tree species (1 coniferous, 1 hardwood). A few months after soil liming, wood ash/dolomite mixture supply increased soil exchangeable cations contents similarly to commercial liming and soil preparation technique interacted with liming type. Both liming types impacted similarly plant community composition, but the type of soil preparation technique had no effect.

Domaines: Biologie végétale; Environnement et Société

Vincent Boulanger, Christine Deleuze, Gwénaëlle Gibaud, Noémie Pousse, Claudine Richter, et al.. Sustainable fuel wood production and wood ash recycling on acidic forest soils. ExpeER International Conference, Sep 2014, Paris, France. ⟨hal-01269159⟩