Nematoda of a Danish Beech Forest. I. Methods and General Analysis

Samples were collected monthly from 85-year-old Hestehave beech forest. Litter, 0-3 cm and 3-6 cm soil strata were extracted separately using the tray method; 25 replicates were used. Total nematode numbers and biomass /m2 are given for each month November 1969-October 1970; mean number was 1,092,695/m2 and biomass 0.282 g/m2. Over 75 nematode species were found. Variation in the monthly abundance of total nematodes, biomass, gravid females, moulting and male nematodes are discussed. Average dry weight of nematodes was 58.5 per cent of the live weight calculated by the Andrassy method. The calorific value of nematode material from mass cultures on agar plates was 4.285 cals/mg ashfree substrate. The mean monthly calorific value of the nematode fauna corrected for extraction efficiency and the unsampled part of the fauna was 796.2 cal/m2. The calorific value of the annual oxygen consumption is 10.1 kcal/m2.