Soil faunal activity as measured by the bait-lamina test in monocultures of 14 tree species in the Siemianice common-garden experiment, Poland

In 1970–1971, 53 tree monoculture study plots were established (20 m × 20 m) in Siemianice (SW Poland) by clearcutting of an 81-year-old pine forest. The following 14 tree species were planted there with 3 or 6 replicates: Abies alba, Acer pseudoplatanus, Acer platanoides, Betula pendula, Carpinus betulus, Fagus sylvatica, Larix decidua, Picea abies, Pinus sylvestris, Quercus robur, Tilia cordata, Pinus nigra, Quercus rubra and Pseudotsuga menziesii. During 34 years of monitoring the soil chemistry, ground floral composition and litter decomposition rates differed strongly between some tree species. The aim of this study was to determine whether tree species also influenced soil faunal activity.In June and October 2006, 50 bait-laminas were distributed in the center of each study plot and exposed for 42 and 33 days, respectively. The soil faunal activity levels in plots of the same tree species were similar but differed between monocultures, being particularly high in monocultures of L. decidua and P. abies. These differences cannot be directly attributed to the soil chemical characteristics. Soil faunal activity was significantly higher in summer than in autumn, although soil moisture was lower in summer (12% at the beginning and 4% at the end of the period) than in autumn (10% and 12%, respectively). The main factor affecting seasonal differences in soil faunal activity seems to be soil temperature, which was significantly higher in summer (mean 19.3 °C) than in autumn (mean 10.1 °C). Faunal activity differed also along the soil profile, with maximum at 0–4 cm depth.