Assessment of the effects of soil and the site environment on collembolan community structure in deciduous forest and coniferous plantations using soil monolith transfer

- Soil effects were observed in different collembolan communities or the two types of vegetation.
- The species composition could be partly explained by the 'soil type' factor.
- Soil effects changed depending on the differences in species composition between two vegetation.

Previous studies have reported differences in collembolan community structure between coniferous plantations and deciduous forests. The reasons for the differences include both soil characteristics and the site environment other than soil. We compared the importance of soil effects on collembolan community structure in coniferous (Japanese cedar) plantation and deciduous forest sites by transferring soil monoliths among them. The soil monoliths included the litter layer, and they were incubated in the field fresh or after defaunation by freezing. They were collected 1 week, 1 month, 10 months, and 13 months after setting.The significant effects of the 'site type' factor on species composition were observed. Effects of the 'soil type' factor on species composition were also observed during the early phase of the experiment. However, only a small portion of the variation in the species composition among monoliths could be explained by the 'soil type' factor. An analysis of species traits revealed that species with spherical body forms were associated with both the sites and soil of cedar plantations (Megalothorax minimus and Neelides minutus) and that species with simple post-antennal organs were associated with both the site and soil of broad-leaved forests (Folsomina onychiurina, Folsomia octoculata, and Dagamaea morei). The percentage of species that preferred the site and soil of broad-leaved forests was significantly lower than the percentage that preferred the sites and soil of cedar plantations. These results suggested that the importance of the 'soil type' factor changed depending on the species composition between cedar plantations and broad-leaved forests.