A review of the study of Oinonen (1956) on ants on rocks and their contribution to forest regeneration in Southern Finland
Abstract:The classical and still valid study of Oinonen (1956) on the species distribution and nesting habits of ants on rocks and their contribution to forest regeneration and tree growth on rocks was reviewed. Oinonen searched ant colonies in 103 sample plots situated on rocks in southern Finland. The plots were classified into three categories according to their vegetation succession stage. The locations of origin, ages, heights and height increment of seedlings were determined. The results indicated that the number of ant species decreased from sites with >50% lichen cover to sites with >50% moss cover and to sites with <50% lichen cover. Lasius flavus was the most common species (5.14 nests per 100 m2), followed by Lasius niger (0.72), Myrmica lobicornis (0.57), Formica fusca (0.38) and Myrmica scabrinodis (0.36). Ant nests were favourable sites for tree establishment, growth and survival. The height growth of 3-14-year-old seedlings averaged 39% higher in ant nests than elsewhere. Ants form favourable microsites for seedlings by collecting organic material and fine mineral soil in their mounds, and thus significantly contribute to forest regeneration on rocks with thin soil cover. The role of ants in postfire forest regeneration on mineral soils was also discussed.
Document Type: Research Article
Affiliations: 1: Finnish Forest Research Institute, Joensuu Research Unit, Joensuu, Finland 2: Section of Biodiversity and Environmental Science, Department of Biology, Finland 3: Department of Forest Ecology, Faculty of Agriculture and Forestry, Finland
Publication date: 2011-02-01