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Disagreements on how fens and bogs are defined warrants an evaluation of how researchers classify these habitats. Ongoing work with a new typology for ecosystems creates an urgency to understand the classification in the field. The aim of this meta-study was to assess authors' naming of fen and bogs habitats, with regards to pH and indicator species and their correspondence to existing classification systems across geographic and research divisions. Even if the terms fen and bog were widely used and understood, application in practice was lacking. Despite tests yielding significant differences and a stratification in the groups bog, poor fen and rich fen according to their pH values, we still note discrepancies and overlaps in definitions of these habitats that steered from our reference values. Different pH-reference intervals can give varying classifications. Moreover, the use of indicator species, beyond some separation between a few North American studies and the rest, showed how the same species were often used for different habitats. The agreement of research practice with our reference definitions should be looked at deeper with the remaining studies of the database. For now, the findings should emphasize the need for a more consistent use of peatland terms in the field.

As they are not only the home of many threatened species, but also one of the main actors in the global carbon cycle, peatlands are highly valuable ecosystems. Human disturbance, in particular drainage for forestry and agriculture, has substantially changed the state of the world’s peatlands and will continue to do so. Lowering the water table by drainage has many hydrological and biological effects, including an increased growth of trees and shrubs as well as reduced growth of the key peat moss genus Sphagnum, leading to peat degradation and release of carbon dioxide. The effects of drainage are sometimes used as predictions for how peatlands will respond to climate change, and undrained mires are thus expected to become more like drained ones in the future. The accuracy of that assumption has, to my knowledge, not been tested on a large scale. Here, I use data from two Swedish national monitoring programs to analyze how the vegetation on drained and undrained mires has changed in recent decades. The results showed an increased tree growth but a decreased establishment of new trees on both drained and undrained mires, implying that contrary to common belief there is no current large-scale afforestation of open mires in Sweden. Sphagnum had, surprisingly, increased on both drained and undrained mires, while other functional groups showed varying results. The tree growth rate was faster on drained mires, but in most other analyses the response to time did not differ depending on drainage regime. Thereby, this study found limited support for the hypothesis that undrained mires are becoming more like drained mires with climate change.

As a consequence to climate change and resulting severe weather events such as prolonged hot and dry periods, wildfire frequency increases globally. Progressively, these effects are noticeable in high latitude countries such as Sweden where a megafire burned 13 100 ha of managed coniferous forest in 2014. While the effect of fire on species communities has been much studied, species surveys often only collect data opportunistically after a wildfire, making inferences about the fire effect uncertain. In this study my aim was to examine the response of peatland dwelling beetles (Coleoptera) to fire by comparing beetle communities of burned drained Swedish peatlands and adjacent non-burned (reference) areas. The first beetle survey took place in 2009, the second was carried out in 2020, 6 years after the fire occurred. Both surveys used pitfall traps in a burned and un-burned area, which were divided into two types of mires, fen and bog, respectively. As a result of the post-fire recovery, dead wood accumulated in the burned area and shrubs and young trees replaced the original vegetation. The reference area did not show significant changes in vegetation. Over all 188 species were found in 2009 and 256 in 2020. In 2009 most species were found in the pre-fire area while in 2020 most species were found in the reference area. Further, two red-listed species (conservation category NT) were found in the fire area as well as two new species for Västmanland country. As expected, the fire had a large impact on the beetle community, where once dominant species declines and got replaced by more dispersive or more moisture striving species. In contrast to my expectations, not only the fire area showed notable changes in the beetle community regarding diversity and composition, also the reference area showed changes in species dominance and a high species turnover. Although the before-after-control-impact study design illustrates the independence of the fire impact to the changes