Cellulose decomposition rates and soil arthropod community in a Pinus halepensis Mill. forest of Greece after a wildfire

Decomposition rate and composition of the soil arthropod community were studied in a severely and a less severely burned patch of a Mediterranean Aleppo pine forest burned by a large scale summer wildfire. Decomposition rates were estimated from the dry mass loss of pure cellulose enclosed in coarse (7 mm) and fine (0.9 mm) mesh bags. The composition of the soil arthropod community was investigated by collecting samples of the burned organic horizon and extracting the animals. The decomposition of cellulose followed the same pattern in both burned patches and mesh bag treatments indicated a similar pattern of decomposer biota activity. Twenty-one arthropod taxa were collected in the less-severely burned patch and sixteen taxa in the severely burned patch; the annual density of their populations was 571.8 and 382.0 ind.m(-2), respectively. Season, post-fire age and fire severity were the determinants for the composition of soil arthropod community. Under the conditions studied, the role of soil arthropods in the decomposition process seems to be less critical as decomposition was successfully accomplished despite both the low number and density of soil arthropod taxa. (C) 2000 Editions scientifiques et medicales Elsevier SAS.