DOI: 10.5061/dryad.wh70rxwjr
title: Data from: Environmental conditions alter successional trajectories on an ephemeral resource: a field experiment with beetles in dead wood

description: Successional processes can be observed for many organisms and resources,
 but most studies of succession have focused on plants. A general framework
 has been proposed, advocating that successional patterns in species
 turnover are predominantly driven by competition, dispersal or abiotic
 limitation, and that the patterning of species accumulation over time
 gives clues to which process is most influential in a given system. We
 applied this framework to succession in communities of wood-living
 beetles, utilizing ephemeral resources in the form of 60 experimentally
 created dead aspen high stumps. High stumps were created at sun-exposed
 sites (high ambient temperature; favorable abiotic conditions) and shaded
 sites (low ambient temperature; abiotically limiting conditions). The
 sites were intermixed, ensuring similar dispersal opportunities. Beetle
 species richness and abundance were monitored with flight interception
 traps over four consecutive years. Consistent with predictions from the
 tested framework, several beetle functional groups accumulated species
 more slowly at the unfavorable shaded sites than at the favorable exposed
 sites. Species richness at the exposed sites increased rapidly to a
 plateau, consistent with a limiting effect of competition on community
 development. Similar results were obtained for beetle abundance and
 community structure. Part of the variance in beetle community structure
 was jointly explained by habitat and fungal community composition,
 suggesting that differences in the composition and developmental rate of
 fungal communities in the two habitats contributed to the observed
 patterns. Targeted experimental studies are now required to decisively
 establish what processes underlie the contrasting successional
 trajectories in the two environments.
description: Data collection: The
 dataset consists of counts of saproxylic beetles sampled in managed forest
 in the southern boreal vegetation zone in Southern Norway. The forest was
 dominated by spruce (<em>Picea abies</em>), with Scots pine
 (<em>Pinus sylvestris</em>), birch (<em>Betula
 pubescens</em>) and aspen (<em>Populus tremula</em>) as
 subdominants. Beetle sampling was conducted by means of large (40cm x
 60cm) trunk-mounted window traps. The traps were mounted on a total of 60
 aspen trees. The traps faced south and were mounted with the lower edge of
 the window pane 1 m above ground. In the late fall of 2001, all trees were
 cut approximately 4 m above ground using detonating chord, in order to
 create standing high stumps. The resulting logs were left in place at the
 base of the high stump. The beetle trapping commenced in 2002-2005,
 operating from mid-May to mid-August in all years. The tress were
 distributed among two landscapes (Nordmarka and Østmarka), with 30 trees
 in each landscape. Within each landscape, 15 trees were located in
 sun-exposed clearings and 15 trees were located in shaded closed forest.
 Refer to the associated journal article for further details about study
 design and sampling. Data processing: All trapped
 beetles were identified to species level. All non-saproxylic species and
 saproxylic species not associated with aspen were excluded from the
 dataset. The remaining species were categorized according to host tree
 affinity, namely aspen specialists (species mainly associated with aspen)
 and aspen generalists (species associated with aspen and other three
 species). The species were also grouped into trophic guilds, namely
 fungivores which feed on fungus or fungus-infested wood, wood-feeders
 which feed on dead wood, predators that attack other wood-living
 invertebrates, and omnivorous or saprophagous species that did not fit
 into the other categories. Refer to the associated journal article for
 further details about data processing.
description: The variables in the dataset are explained in the associated
 ReadMe file.