Even the smallest habitat patch matters: on the fauna of peat bogs

Abstract

Peat bogs are highly endangered and very sensitive habitats in Central Europe. Their high water table, acidity and characteristic climate determine their specialized flora and fauna with numerous rare species. Peat bogs are threatened by soil erosion and nutrient infiltration due to forestry management or grazing. Several small, natural peat bogs exist in the Carpathians, mainly covered with birch and pine forests. Here we assessed the effect of geological location, peat bog size and tree species on the spider fauna. We collected spiders with pitfall traps in eight peat bogs in Eastern Transylvania. We identified several species of high nature conservation value, regarded to be rare in the Central-European fauna. We found higher species richness, abundance and diversity in birch forests than in pine forests. The open canopy of birch forests may allow open habitat specialists to occur in high densities in these forests. Species composition was affected by geological location, indicating that the regional fauna of peat bogs in different mountain ranges are isolated. However, we found no significant effect of habitat area on spider assemblages, the valuable tyrphophilic spider fauna was present even in the smallest peat bog. Peat bog spider fauna requires specific habitat conditions, we suggest that preserving hydrological properties and water quality even in the smallest bogs would conserve the specialized fauna.

Tree species and microhabitat affect forest bog spider fauna

“…This is in line with several studies of the spider fauna Eastern Carpathian peat bogs emphasizing the unique nature conservation value of peat bogs (e.g. Urák 2002, 2006;Gallé et al 2019, Samu andUrák 2014). Our results show that the patchy microhabitat structure further increases the spider diversity of bog forests.…”

“…Peat bogs are relatively common and widespread worldwide. Although their overall surface area is small, cca 3%, they have a key role in carbon storage (Joosten and Clarke 2002;Urák et al 2017) and harbour a disproportionately high number of specialist species (Gajdos et al 2016;Gallé et al 2019). This distinct arthropod community of bog forests have numerous, mainly cold-adapted arthropod species that significantly contribute to the regional species richness (Sławska et al 2017).…”

“…The cold-adapted species with restricted ranges are vulnerable to climate change, and bogs may serve as important micro-refugia for them (Ohlemüller et al 2008;Gallé et al 2019). Central European bogs are highly threatened by anthropogenic activities, such as drainage, peat extraction, and eutrophication (Haase and Balckenhol 2015).…”

Effect of Herbage Density, Height and Age on Nutrient and Invertebrate Generalist Predator Abundance in Permanent and Temporary Pastures

“…Local versus landscape arguments about what matters for these beneficial invertebrates, many of which are capable of dispersing over large distances, with the ability to rapidly colonise new areas, remain incompletely understood [36]. The findings in our study here indicate that, as has been found by other authors, small scale patches may be important, notwithstanding ongoing processes at much larger scales [37]. Furthermore, the life cycle of lycosids and carabids are not the same.…”

Long-term microclimate study of a peatland in Central Europe to understand microrefugia

“…Such locations are referred to as microrefugia (Ashcroft and Gollan 2013;Gubler et al 2018;Rull 2009). Numerous studies analyzing different temporal and spatial microhabitat characteristics have indicated that the heterogeneity of habitats (Gallé et al 2019), including their microclimates (Bramer et al 2018), is underestimated. Free-air measurements obtained in standard meteorological stations at a height of 1.5-2.0 m over short grass or natural soil, in accordance with the guidelines of the World Meteorological Organization (WMO) (De Frenne et al 2019;WMO 2018), provide general data about the macroclimate of an ecosystem.…”