Conditions affecting ant nesting in stumps in a temperate coniferous planted forest

Tanaka M., Baek S., Tochigi K., Naganuma T., Inagaki A., Dewi B. & Koike S.
Forest Ecology and Management
537: E1yx8
Url: 120976_x000D_10.1016/j.foreco.2023.120976
Dead trees are an important component of forest ecosystems as they play various roles in these ecosystems and their biodiversity. The use of dead trees as a habitat and foraging resource by various organisms affects the decomposition of the trees. Ants use dead trees as nests and slow their decomposition by weakening the function of decomposers, such as fungi and termites, through interspecific interactions. However, our understanding of the characteristics of dead trees in which ants nest and the environmental conditions under which they exist is limited. In planted forests, stumps left after harvesting account for the largest biomass of deadwood. In the present study, the characteristics of such stumps, their location, and the relationship between these factors were determined in relation to ant nesting in a warm temperate conifer planted forest (a university forest with clear past history located in central Japan). In total, 85 stands consisting of Cryptomeria japonica or Chamaecyparis obtusa were surveyed, and various environmental conditions as well as the presence or absence of ant nests in stumps logged by forestry operations were recorded. In total, 1551 stumps were surveyed, of which 113 stumps contained ant nests with 16 different ant species. Modeling and Akaike information criterion evaluation results revealed that both large and small ant species tended to nest in old stumps located in areas with an open canopy, large species tended to nest in stumps with moss or lichen cover, and small species tended to nest in stumps with bark cover. Older stumps are typically softer owing to more decomposition, and solar heat can facilitate tem-perature control inside the nest, which may explain why ants tended to nest under the observed conditions. Based on these findings, long-term continuous thinning rather than clearcutting, which results in excessively large canopy openings and uniformly sized stumps, is the preferred management practice for promoting ant nesting in stumps in planted forests. ant nest, conifer plantation, dead tree, formicidae, thinning, coarse woody debris, black bears, dead wood, soil, hymenoptera, succession, ecology, boreal, size
Wednesday, 17 May 2023 10:58