Field decomposition of leaf litters: earthworm–microorganism interactions —the ploughing-in effect

摘要: Abstract We describe a new decomposition model including the consequences of earthworm mechanical activity, especially ploughing-in effect. In an experiment we tested this effect on disappearance leaf litter from four tree species (sessile oak, Quercus petraea L., holm ilex sweet chestnut, Castanea sativa Mill and beech, Fagus sylvatica L.) during two 2 y exposure at site Anduze which contained highest biomass. Our experiment, carried out with placed in litterbags allowing (0.5 cm mesh size) or preventing (0.1 cm access earthworms, confirms (1) rates observed first (2) important earthworms (from 20.5% to 30.2% depending litter). The breakdown different litters by soil fauna varied 24.2% 40.6% after field rate was increased mean factor about 5.2. technique for detecting contamination attributed casts. This is based change total weight loss (TWL)-to-litter C (TCL) ratios 0.652 0.915 presence were close 1 0.952 0.995) absence earthworms. assumed that large these indicated mineral due casting. hypothesis confirmed ash contents varying 2.6% 9.6% 1.3% 2.1% without only. These results point ecological importance casts decomposition.