Dynamics of soil Collembola communities (Hexapoda: Collembola) along the mesoclimatic gradient in a deep karst valley

The two-year dynamics of soil collembolan communities were studied at five sites along the mesoclimatic gradient in a deep karst valley, from the karst plateau to the bottom of the deep karst gorge in the Zádiel Valley, Slovak Karst, Slovakia. Within the local gradient the annual soil temperature means ranged from +8.88 ± 6.72°C on the plateau (pasture) to +5.16 ± 6.24°C at the bottom of the gorge (maple-hornbeam wood). Repeated ANOVA confirmed a significant effect of site, year, month and combined factors (year x month, year x month x site) on Collembola abundance (P < 0.0001). The marked spring minimum in abundance dynamics and species richness of communities recorded in the gorge were not observed at the thermophilous sites. The collembolan abundance means at both sites in the gorge were extremely low and significantly different (P < 0.001) from those of the rest of the study period, delayed into the early summer as a direct effect of mesoclimatic inversion within the karst valley. During the drier year a more marked gradient was observed in the deep karst valley, leading to greater changes in the dynamics of dominant species Isotomiella minor and Parisotoma notabilis.