Over the last millennium peatlands have accumulated significant carbon stores. Drainage for agricultural use has been widespread and has altered the functioning of these mires: shifting them towards carbon release. Recently, in recognition of the range of ecosystem services derived from these landscapes peatland restoration projects have been initiated. Carbon storage is often cited amongst the aims of these projects, especially since the inclusion of rewetting wetlands in the Kyoto Protocol. However, little is known about the effects of ditch blocking on CO2 fluxes, particularly in Molinia caerulea dominated peatlands, a species common on degraded peatlands which tolerates a range of water table depths. This thesis aims firstly to quantify CO2 fluxes from a drained Molinia caerulea dominated blanket bog and to improve understanding of the temporal and spatial controls on these fluxes and secondly, to quantify the immediate effects of ditch blocking. Closed chamber measurements of net ecosystem exchange and partitioned below-ground respiration from control-restored paired sites were collected over the growing seasons immediately pre- (2012) and post-restoration (2013/2014). These flux data were coupled with remotely sensed data quantifying vegetation phenology and structure with a fine resolution (daily/cm) over large extents (annual/catchment). Although temporal variation in water table depth was not related to CO2 fluxes, the seasonal average related to vegetation composition suggesting raising water tables may promote a change in vegetation composition within these species-poor ecosystems. The distribution of water table depths, vegetation composition and CO2 fluxes did not vary with proximity to drainage ditches despite their prominence. An empirical model suggests in a drained state these peatlands are CO2 sources, indicating carbon previously accumulated is gradually being lost. Data suggest restoration does not always significantly affect water tables and consequently CO2 fluxes in the short-term. Where shallower water tables were maintained during dry conditions photosynthesis decreased and heterotrophic respiration increased: enhancing carbon release. Research undertaken during atypical weather has been unable to determine if restoration will be able to raise water tables sufficiently to protect the existing peat store and promote the vegetation change required to reinstate CO2 sequestration in the longer-term.

Svenska våtmarker har under flera hundra år dikats ut till förmån för odling av grödor och virkesproduktion. Idag ser verkligheten annorlunda ut och till förmån för klimatet satsar svenska staten nu pengar på att plugga igen diken och återställa dessa numera uttorkade våtmarker. Att huvudsyftet är minskade utsläpp av växthusgaser hindrar dock varken flora eller fauna från att utnyttja dessa nya habitat. Då hotet mot biodiversiteten i världen enligt forskningen är lika allvarligt som klimatförändringarna är det av intresse att veta hur åtgärder för att minska utsläpp av växthusgaser även påverkar artrikedomen lokalt och regionalt. Detta är en studie som utvärderar insektsfaunan på återställda våtmarker och om det går att urskilja några naturvärden baserat på vilka arter som hittats. Mellan 8 augusti och 8 september 2022 användes tre inventeringsmetoder på fyra skogslokaler och tre återställda våtmarker. Lokalerna som stod klara år 2021 är Skogsstyrelsens pilotprojekt för återvätningar. Resultatet visade att även om inga naturvårdsarter hittades, bidrar klimatgynnande återvätning av skogsmark till en ökad biodiversitet redan på kort sikt. Totalt inventerades individer av 35 olika arter och 71% fler arter hittades i våtmarkerna än i skogarna. Sex fynd var arter som specifikt föredrar våtmarker och hittades i lokalerna med öppen vattenspegel, övriga arter i våtmarkerna var generalister. Då många faktorer kan påverka olika arters migration är långsiktig övervakning eftersträvansvärt. Den här studien ger en chans för framtida uppföljning av våtmarkernas utveckling och arters etablering. Vidare en möjlighet att anpassa framtida återvätningar för att minimera utsläpp av växthusgaser och samtidigt maximera biodiversiteten. / Swedish wetlands have been drained by ditching for several hundreds of years in favour for forestry and agriculture. Today, the reality looks different, and due to the climate change the Swedish government is now investing money to plug ditches and restore these now dried-up wetlands. The main purpose is to reduce greenhouse gas emissions, but neither flora nor fauna are prevented from utilizing these new habitats. According to research, the threat to global biodiversity is as serious as climate change, it is of interest to know how measures to reduce greenhouse gas emssions also affect local and regional species richness. This is a study that evaluates the insect fauna in restored wetlands and wether any natural values can be discerned based on the species found. Between August 8 and September 8 2022, three sampling methods were used in four forest locations and three restored wetlands. The wetlands which were completed in 2021 are the Swedish Forest Agency´s pilot projects for rewetting. The results showed that even if no conservation species were found, climate-beneficial rewetting of forest land contributes to increased biodiversity in the short term. In total, individuals from 35 different species were surveyed and 71% more species were found in the wetlands than in the forests. Six findings were species that specifically prefer wetlands and were found in locations with open water surfaces, all other species were generalists. As many factors can influence the migration of different species, long-term monitoring is desirable. This study provides an opportunity for future follow-up of the development of wetlands and the establishment of species. Furthermore, an opportunity to adapt future rewetting to both minimize greenhouse gas emissions and at the same time maximize biodiversity.