Infodoc : Sciences, Techniques et Culture

The purpose of this work is to assess the risks deriving from current forestry practices on the sustainability of soil function and ecosystems. The relationship between the production function and the soil conservation function translates as a certain conflict between these two options. Stresses on the chemical fertility of the soil were analysed from the least intensive to the most intensive treatments, i.e. from forest reserves to very short rotation, treated lignocellulosic crops. Under the extensive systems, high grade biological recycling is sustainable if logging is confined to trunks alone. Dressings can correct the slow but inevitable acidification of soils. When treatments are intensive, the natural fertility of forest soils cannot sustain production; only soils with suitable[...]

The purpose of this work is to assess the risks deriving from current forestry practices on the sustainability of soil function and ecosystems. The relationship between the production function and the soil conservation function translates as a certain conflict between these two options. Stresses on the chemical fertility of the soil were analysed from the least intensive to the most intensive treatments, i.e. from forest reserves to very short rotation, treated lignocellulosic crops. Under the extensive systems, high grade biological recycling is sustainable if logging is confined to trunks alone. Dressings can correct the slow but inevitable acidification of soils. When treatments are intensive, the natural fertility of forest soils cannot sustain production; only soils with suitable physical qualities combined with application of appropriate inputs enable sustained high levels of output to be achieved, in particular under the short rotation systems.
Ce travail tente d’évaluer les risques que font peser les pratiques forestières actuelles sur la durabilité des fonctions des sols et des écosystèmes. La relation entre fonction de production et fonction de conservation des sols traduit une certaine antinomie entre ces deux options. Les contraintes pour la fertilité chimique du sol sont analysées pour les traitements des moins aux plus intensifs, c’est-à-dire des réserves forestières aux cultures lignocellulosiques traitées à très courte révolution. Dans les systèmes extensifs, le recyclage biologique performant est durable si les exploitations se cantonnent aux seuls troncs. Les amendements permettent de corriger l’acidification lente et inéluctable des sols. Dans les traitements intensifs, la fertilité naturelle des sols forestiers ne peut soutenir la production ; seuls les sols de qualité physique convenable et avec apports d’intrants peuvent conduire à des productions élevées et soutenues, en particulier dans les systèmes à courte révolution.