Mites (Acari, Mesostigmata) in boreal Scots pine forest floors: effect of distance to stumps

Abstract

Coarse woody debris (CWD) is a basic component of forest ecosystems and it plays a crucial role in species-poor boreal forests. Generally, previous studies have focused on differences between the forest floor and decaying logs of various tree species. The impact of distance to CWD has been investigated mainly for forest-floor snails and some groups of macrofauna, but not yet for mesostigmatid mites communities. We hypothesized that the effect of CWD decreases with increasing distance from CWD. To test this hypothesis we conducted a study in relatively species-poor Finnish boreal forest (at ca. 100 km northwest of Helsinki). In total, 81 samples were collected in 2007 from nine Scots pine (Pinus sylvestris) stumps, three microhabitats (CWD, soil/litter at 0.5 m from a stump and soil/litter at 1.5 m from a stump) and in three main directions (9 stumps × 3 microhabitats × 3 directions). Overall, 1965 mesostigmatid mites were collected representing 24 species. The mean number of mite species collected was significantly different between decaying stumps and forest litter; however, there was no significant difference between the litter samples at 0.5 and 1.5 m distance. The evenness index was significantly lower for samples collected from stumps than for litter in close (0.5 m) or far (1.5 m) distance. The most frequently encountered mite species were Veigaia nemorensis, Parazercon radiatus and Zercon zelawaiensis.

To what extent do pine and oak clear-cut stumps support mite (Acari: Mesostigmata) communities in temperate forests?

“…Therefore, stumps can play a role as an ecological island for mites. This is in agreement with our studies conducted in boreal forest (Kamczyc et al, 2014). These results are similar to those published by Jabin et al (2004), who reported higher densities of Chilopoda and Pseudoscorpionida in close distance (<10 cm from logs) to moderately decayed logs in a managed oak-beech forest and those published by Castro and Wise (2010), who found a higher density of forest-floor spiders in the litter immediately adjacent to CWD.…”

“…In contrast to logs, stumps are the least explored form of CWD. In an environment of litter, they form an ecological island (Kamczyc et al, 2014) and are characterized by a higher species richness than logs (Skubała and Marzec, 2013). Research conducted on stumps of different species pointed to differences between species, but the study was carried out in poor, boreal old-growth forests and did not include distance measurements (Huhta et al, 2012).…”

“…Research conducted on stumps of different species pointed to differences between species, but the study was carried out in poor, boreal old-growth forests and did not include distance measurements (Huhta et al, 2012). The role of stumps as ecological islands, together with their impact on the surrounding litter, was determined only for boreal pine forests (Kamczyc et al, 2014). The impact of Collembola, Nematoda Setälä and Marshall, 1994;Setälä et al, 1995.…”

Edaphic characteristics and environmental impact of rubber tree plantations on soil mite (Acari) communities

“…Probably, the soil cores were taken away from the stumps. In fact, with increasing distance to stumps, the total number of mite species in the soil/litter matrix decreases (Kamczyc et al 2014). Similarly, a consistent pattern of lower diversity indices and evenness in the secondary forests than in the rubber plantations was observed.…”

Stump harvesting for bioenergy: A review of climatic and environmental impacts in northern Europe and America

“…In another study from BC, Setälä and Marshall (1994) and Setälä, Marshall, and Trofymow (1995) showed that decaying stumps of Douglasfir harbored a species-rich (72 species) and abundant community of Collembola. In southern Finland, many mesostigmatid mites were common to both stumps and soil, but some species were exclusively found in stumps (Kamczyk, Gwiazdowicz, Teodorowicz, & Strzymi nska, 2014).…”