Relations entre la microtopographie, les caractéristiques de la couverture morte et la répartition des essences dans une érablière à Bouleau jaune

Abstract

Some effects of microtopography on forest floor, organic matter dynamics, and tree species distribution were studied in a northern hardwood stand near Québec. Forest floor thickness was 12.4 cm in pits while it was only 7.6 cm on mounds. These variations in thickness were attributed to a smaller litter accumulation (186 vs. 318 g m−2 year−1 in pits) and a more rapid decomposition on mounds (weight losses of wooden probes, 17.3 vs. 13.7% in pits). Over 43% of yellow birch stems (Betulaalleghaniensis Britton) were found on mounds in comparison with 20% for beech (Fagusgrandifolia Ehrh.). Sugar maple (Acersaccharum Marsh.) distribution was intermediate between those species. Thus, mounds seem more suitable for yellow birch installation, either because of their characteristics after their formation or because of the thinner forest floor formed on these microsites.