Nowadays a greater number of people live in cities than in earlier times. In Finland, the portion of urban dwellers has nearly doubled in last 50 years. The urbanization has had undisputable benefits for mankind but it has also had widespread negative effects on nature. As cities grow natural habitats are replaced by spreading infrastructure. Remaining mires, forests and other natural habitats are smaller and more isolated than their rural counterparts. These urban habitats are affected by increased pollution and nutrient loads, trampling and other detrimental effects caused by human activity. Alien invasive species may also spread into indigenous vegetation and more of these areas are affected by edge-effects. Ombrotrophic bogs are one of the most nutrient-poor habitats in the North and receive nutrients only by dry and wet deposition. They have been reported to suffer from increased nutrient deposition. Hydrology also has a vital part in function and form of ombrotrophic bogs. Spread of urban infrastructure may alter the way bogs receive water due to increased sealed surface in the catchment areas of these bogs. The effects of urbanization on ombrotrophic bogs in Finland has not been studied previously and the aim of this Master’s thesis is to examine the differences between vegetation in urban and rural bogs and the effects of the size of bog area, nearby population and total N content of surface peat on bog vegetation in different bog types: dwarf shrub pine bogs, low sedge bogs, Sphagnum fuscum pine bog and Sphagnum fuscum bog. Last two were studied together due to their similarities. According to this study the differences between urban and rural bogs in Southern Finland are small. The greatest differences were observed among dwarf shrubs typical for bogs but the effects varied between bog types. In dwarf shrub pine bogs, the amount of dwarf shrubs decreased while in low sedge bogs, the cover of Vaccinium oxyccocos, and in Sphagnum bogs, the occurrence of Empetrum nigrum increased. The bogs studied in urban sites were generally smaller and more isolated than rural bogs. Around urban bogs, there were also significantly higher number of residents than in rural areas, and one of the most distinct effects of urbanization on bog vegetation discovered was reduction of cover and appearance of species vulnerable to trampling. The increased nutrient loads usually reported in urban habitats was not visible in nitrogen content of surface peat. On the contrary, low sedge bogs seemed to have higher nitrogen content on rural bogs, which may be caused by intense agriculture in rural areas. The reason for not detecting increased urban nitrogen deposition based on peat samples may be caused by increased nitrogen uptake of Sphagnum mosses. Sphagnum mosses have been reported to benefit from increased nitrogen deposition until they reach nitrogen saturation point. After this the excess nitrogen enters peat soil. Low nitrogen deposits in Southern Finland can probably be used fully by Spaghnum mosses and thus no increase in nitrogen content was observed. The results of this study indicate that ombrotrophic peat bogs are at least partly resistant to the effects of urbanization. The level of urbanization in Finland is lower than in Central Europe, which may lead to lowered levels of detrimental effects caused by urbanization. Alien species are probably also unable to invade the acidic and nutrient poor urban bogs. The mire types studied here are also usually situated in the centre of ombrotrophic bogs and may have avoided most of the edge effects. However, if studied, the edges of the urban bogs might have shown large number of harmful effects caused by urbanization.

The monograph is a generalization based on the analysis and synthesis of the voluminous scope of data on the dynamics of palaeovegetation and its mapping, along with aspects of palaeogeography of the Kola Peninsula and Karelia. All the elements of past landscapes are considered against the background of the present state of environments: geology, geomorphology and vegetation. The interval under consideration embraces the Late Glacial Time (12 000-10 300 years BP) and the Holocene (from 10 300 years BP up to the present). The book discusses the methodical and theoretical treatments of the last decade. As a result, the dynamics of past landscapes are shown in the unity of all their components (i.e., relief, hydrology and vegetation), and in comparison with their present-day parameters. Cartographic and textual materials on geology and modern vegetation as well as palaeovegetation maps of model territories used in this book are entirely original. The model territories are rather evenly distributed throughout the Kola Peninsula and Karelia. Seven of them are represented in this work; for each of model territory, a series of maps (for 10 500, 9 500, 8 500, 5 500, 3 000, and 1 000 years BP) are provided, correlated with relief and present-day vegetation. The second stage of data generalization is a comparison of maps related to the same temporal sections. The sequence of the maps from ‘older’ to ‘younger’ characterizes the dynamics of chorological palaeovegetation units. These dynamics readily illustrate shifts of geographical zones in space and time.

Mires from pole to pole is a proceedings volume of the XII biennial International Mire Conservation Group symposium held in Finland 24.-27.7. 2006. The following topics are included in the volume: 1. Towards the understanding of the variety of mires and their conservation in different countries, 2. Patterns in polygon mires in north-eastern Yakutia, Siberia: The Role of Vegetation and Water, 3. Mires on the map of Russia, 4. Development of the large-scale hydrotopography of aapa mires on the land-uplift coastland in northern Finland, 5. The development of patterning on a succession series of aapa-mire systems on the land-uplift coast of northern Ostrobothnia, Finland, 6. The beginning of agriculture in Swedish Lapland, 7. Moss diversity in the mires of the Maanselkä water divide, 8. Vegetation studies and mapping in Juortanansalo mire reserve, eastern Finland, 9. Holocene vegetation dynamics and carbon accumulation of two mires in the Friendship Park, eastern Finland, 10. Vegetation dynamics of the Ileksa-Vodlozero aapa mires, 11. Vegetation of forested mires in the middle boreal subzone of Karelia, 12. Mire flora, vegetation and conservation in the Republic of Karelia, Russia, 13. Mire types of the southern part of Kenozero National Park, Arkhangelsk region, NW Russia, 14. Postdrainage vegetation dynamics in mesotrophic herb-Sphagnum mires of southern Karelia, Russia, 15. The Finnish peat mining paradox: political support to environmental calamity, 16. Nationally and regionally threatened mire mosses in Finland, 17. Assessment of threatened mire habitats in Finland, 18. Monitoring restored peatlands in Finnish nature reserves, 19. Species richness and abundance of butterflies in natural and drained mires in Finland, 20. Impacts of peatland restoration on nutrient leaching in western and southern Finland, 21. Role of protected areas in maintaining the diversity of peat mosses in the Karelian Isthmus and Gulf of Finland islands (Leningrad Region, northwest Russia), 22. Sphagnum cover surface shape variations during vegetation period, 23. Plant cover of natural mires and disturbed peatlands in Meschera National Park, Russia, 24. Management and monitoring of three Latvian raised bogs and a fen, 25. The Origin, Development, and Modern State of Karst Mires in the Tula Region of Russia, 26. Subsidence in bogs. Moving catchment boundaries, changing flow paths and slopes, self-sealing and effects on drying and natural rewetting, 27. The importance of gradual changes and landscape heterogeneity for aquatic macroinvertebrate diversity in mire restoration management, 28. Mires in Slovakia - present status and conservation, 29. Status and Protection of Heilongjiang Wetlands in North-eastern China, 30. Experimental grazing management on peatlands of the French Basque Land, 31. Hydrogeochemical Investigation of Peatlands and related Vegetation Complexes, 32. The invasive alien plant species of Kolkheti lowland, Georgia, 33. Spatial analysis and description of eastern peatlands of Tierra del Fuego, Argentina, 34. Mires Down Under – the Peatlands of Australasia.

Mires have a significant role in climate change mitigation due to their enormous carbon storage and due to the fluxes of greenhouse gases between ecosystem and the atmosphere. Global warming is predicted to affect mire vegetation indirectly through increased evapotranspiration leading to decreased water table levels down to 14–22 centimeters. Water level drawdown is likely to affect the vegetation composition and consequently the ecosystem functioning of mires. Previous studies covering the first years following water table level drawdown have shown that vascular plants benefit from a lower water table and hollow-specific Sphagnum species suffer. In addition to changes in plant abundances the diversity of plant communities decreases. The lawn and hollow communities of Sphagna and sedges are found to be the most sensitive plant groups BACI (before-after-control-impact) experimental approach was applied to study the responses of different functional mire plant groups to water level drawdown. There were 3 control plots and 3 treatment plots with moderate water level drawdown. In addition there were 3 plots drained for forestry 50 years ago as a reference. The plots were located in meso-, oligo- and ombrotrophic sites in Lakkasuo (Orivesi, Finland). The vegetation was surveyed and the water table (WT) was measured from permanent sampling points before ditching in 2000 and during the years 2001–2003 and 2009. The data was analyzed with multivariate methods such as TWINSPAN (PC-Ord), PRC and DCA (CANOCO). Overall results show that the control and treatment plots were similar before the treatment which is crucial in studies conducted with BACI- experimental design. The vegetation composition in the varied between the years also in the control plots following variation in weather conditions, i.e. growing season temperature and precipitation. The year 2003 stood out with lowest water table levels and with highest coverage of the evergreen vascular plants in all plots. By 2009 there was a dramatic decrease in sedge species cover. There seems to be more changes in bryophyte cover in mesotrophic sites than in ombrotrophic ones. The hummock-specific Sphagna seem to be resilient to WT drawdown. Especially lawn- and hollow-specific bryophytes responded to WT drawdown. Results show that all plant groups have a different short and long term response to water level drawdown. The first three years after ditching appeared to be a disturbance state. Only after that the vegetation started to adapt to the lowered water table conditions.