Tree regeneration and plant species diversity responses to vegetation control following a major windthrow in mixed broadleaved stands
Résumé
By increasing resource availability, canopy opening enhances tree recruitment as well as the development of neighbouring vegetation. The proliferation of early successional and highly competitive vegetation may have dramatic consequences on seedling establishment. However, differences in competitive abilities have been shown among the plant growth forms commonly encountered in forests. We may thus expect that vegetation management leading to control of different plant growth forms would have different consequences on tree seedling growth and development. To test this hypothesis, we analysed the effects of an intensity gradient of four vegetation control treatments (untreated, coppice control, coppice and non-tree plant control, and coppice, non-tree and pioneer (tree) plant control) on plant species richness and natural tree regeneration in three post-storm sites. Higher plant species richness and a better natural tree regeneration were observed in the more intensive treatments that significantly improved the balance of the relative abundance of tree species. Suppressing the more competitive vegetation, mainly Rubus fruticosus and graminoids, led to the recruitment and growth of tree species sensitive to competition and good tree species diversity. Practical recommendations in terms of vegetation control relative to tree regeneration and plant species richness are given.
Mots clés
VEGETATION CONTROL INTENSITY PLANT SPECIES RICHNESS
NATURAL TREE REGENERATION
COMPETING VEGETATION
CANOPY OPENING
FOREST VEGETATION MANAGEMENT
BEECH FOREST
UNDERSTOREY VEGETATION
SOIL COMPACTION
COMPETITION
MANAGEMENT
DYNAMICS
LIGHT
STORM
DISTURBANCE
PATTERNS
HETRE COMMUN
OUVERTURE DU COUVERT VEGETAL