The heterogeneity of humus profiles and earthworm communities in a virgin beech forest

Influence of ground cover on earthworm communities in an unmanaged beech forest: linear gradient studies

“…It is probable that at the time of the present study (July) some species such as Aporrectodea longa retreated deep in their burrows and were in a phase of quiescence [43] but all other species previously found on the site [35,36] were retrieved, indicating that aestivation did not affect the studied site to a great extent. [38] rather than by some heterogeneity in the fall of litter, given the small size (13 m) of this single-tree gap, compared to 40 m for the height of adult beech at this location [29].…”

“…following abandon of pasture during the 16 th century then of sylviculture during the 17 th century. Geomorphological features are at the origin of a wide variety of soil conditions [35].…”

“…The thickness of the blown sand varies from 30 cm to 230 cm or more [36]. Access to lime by earthworms and trees determines a variety of humus forms from eumull to dysmoder [35]. Ground vegetation is acidophilic to neutrophilic according to enrichment in calcium of upper soil horizons by beech litter and deep-burrowing earthworms [36].…”

“…All variables were then subjected to reweighting and focusing, i.e. their mean and variance were fixed to 20 and 1 respectively [35].…”

“…The appearance of gaps in the canopy following single or multiple windthrows or windbreaks is at the origin of the local development of a successional process that ensures the renewal of the forest ecosystem [21]. Earthworms play a part in the regeneration of late-successional trees such as spruce and beech, the forest patchwork being composed of refuge (mature, senescent phase) and depopulation (pole phase) units [3,35].…”