Boreal Mire Research Articles

New bryological data from relict mires in the Gran Sasso-Laga National Park (Central Apennines) and their interpretation according to the EUNIS classification and Habitats Directive

During a phytosociological field-work campaign aimed at studying some relict Scheuchzerio-Caricetea boreal mires of the montane and subalpine belts of the Laga Mountains, the highest and largest siliceous massif of the Apennine range, several bryophyte taxa of particular biogeographic interest were collected. Among these taxa, Schljakovia kunzeana and Ptychostomum cernuum were found to be new records for the whole Apennine range while Hamatocaulis vernicosus (taxon included in annex II of Habitats Directive) and Scorpidium cossonii as new for the Central-Southern Apennines. Two further species, Bryum canariense, Plagiomnium cuspidatum, were found to be confirmations of old records for the Central Apennines dating back to the early 1900s. At the national and regional level, nine, out of the forty-four bryophyte taxa identified in this study, were found to be new for the Lazio administrative Region, and one taxon as new for the Abruzzo Region. The majority of these new records belong to the boreal chorotype, the Laga Mountains being one of the most important conservation sites for the relict circumboreal and arctic-alpine flora in the whole Mediterranean area. According to both the EUNIS Habitat classification and the EU Habitats Directive Annex I, several, out of the 44 bryophytes identified in this study, act as diagnostic species for European Community Habitats. Nevertheless, a complete correspondence between bryophyte taxon and habitat type was not found upon comparing these two environmental policy systems.

Methane Producing and Oxidizing Microorganisms Display a High Resilience to Drought in a Swedish Hemi‐Boreal Mire

AbstractAn increased frequency of droughts due to anthropogenic climate change can lead to considerable stress for soil microorganisms and their functioning within northern peatlands. A better understanding of the diversity and relative abundance of methane producing and oxidizing taxa, and their functional genes, can help predict the functional potential of peatlands and how the microorganisms respond to disturbances such as drought. To address knowledge gaps in the understanding of how functional genetic diversity shifts under drought conditions, we investigated a hemi boreal mire in Southern Sweden. Environmental parameters, including soil and air temperature, precipitation, and water table depth, as well as methane flux data were collected during the summer of 2017 under typical growing conditions, and in 2018 during a drought. In addition, the diversity and composition of genes encoding for methane metabolism were determined using the captured metagenomics technique. During drought we observed a substantial increase in air and soil temperature, reduced precipitation, and a lower water table depth. Taxonomic and functional gene composition significantly changed during the drought, while diversity indices, such as alpha and beta diversity, remained similar. These results indicate that methane producing and oxidizing microbial communities, and their functional genes, displayed a resilience to drought with specific genera having the ability to outcompete others under stress. Furthermore, our results show that although methane emissions are substantially reduced during drought, we can expect to see a shift toward more resilient methanogens and methanotrophs under future climate conditions.

Catchment characteristics control boreal mire nutrient regime and vegetation patterns over ~5000 years of landscape development

Vegetation holds the key to many properties that make natural mires unique, such as surface microtopography, high biodiversity values, effective carbon sequestration and regulation of water and nutrient fluxes across the landscape. Despite this, landscape controls behind mire vegetation patterns have previously been poorly described at large spatial scales, which limits the understanding of basic drivers underpinning mire ecosystem services. We studied catchment controls on mire nutrient regimes and vegetation patterns using a geographically constrained natural mire chronosequence along the isostatically rising coastline in Northern Sweden. By comparing mires of different ages, we can partition vegetation patterns caused by long-term mire succession (<5000 years) and present-day vegetation responses to catchment eco-hydrological settings. We used the remote sensing based normalized difference vegetation index (NDVI) to describe mire vegetation and combined peat physicochemical measures with catchment properties to identify the most important factors that determine mire NDVI. We found strong evidence that mire NDVI depends on nutrient inputs from the catchment area or underlying mineral soil, especially concerning phosphorus and potassium concentrations. Steep mire and catchment slopes, dry conditions and large catchment areas relative to mire areas were associated with higher NDVI. We also found long-term successional patterns, with lower NDVI in older mires. Importantly, the NDVI should be used to describe mire vegetation patterns in open mires if the focus is on surface vegetation, since the canopy cover in tree-covered mires completely dominated the NDVI signal. With our study approach, we can quantitatively describe the connection between landscape properties and mire nutrient regime. Our results confirm that mire vegetation responds to the upslope catchment area, but importantly, also suggest that mire and catchment aging can override the role of catchment influence. This effect was clear across mires of all ages, but was strongest in younger mires.

Using Spectral Indices Derived from Remote Sensing Imagery to Represent Arthropod Biodiversity Gradients in a European Sphagnum Peat Bog

Monitoring of peatlands is an important conservation issue. We investigated communities of soil mites (Acari: Oribatida, Mesostigmata) inhabiting a relatively undisturbed European boreal mire characterized by a mosaic of oligotrophic and meso-eutrophic areas. We assess the potential of using remote sensing approach as a mapping and predictive tool for monitoring productivity and arthropod biodiversity in a peat bog. In georeferenced plots, Acari biodiversity, water table level, water pH and plot productivity class on the oligotrophic-eutrophic gradient were recorded. Data from the Landsat 8 OLI sensor were used to calculate several spectral indices known to represent productivity and surface moisture gradients in terrestrial ecosystems. We then explored the relationship between spectral indices, environmental gradients and biodiversity of mites. We found that several spectral indices were significantly and consistently correlated with local environmental variables and biodiversity of soil mites. The Excess Green Index performed best as a predictor of plot trophic class on the oligotrophic-eutrophic gradient and showed significant relationship with Oribatida diversity in 2016. However, following hot summer in 2019, there was no significant relationship between abundance and species richness of Oribatida and remotely sensed data; there was a weak correlation between abundance of Mesostigmata and spectral indices which represent surface moisture gradient (e.g., Normalised Difference Moisture Index). We discuss advantages and challenges of using spectral indices derived from remote sensing imagery to map biodiversity gradients in a peatland.

Topology, Vegetation and Stratigraphy of Far Eastern Aapa Mires (Khabarovsk Region, Russia)

Aapa mires (string-flark fens) are one of the main types of mires in northern Eurasia. It has an almost continuous distribution from Scandinavia to Kamchatka, disappearing in continental climate areas and becoming one of the dominant types in more oceanic zones. This article first presents the topological features of string-flark aapa, their vegetation and peat stratigraphy related to different elements of microrelief at the southernmost borders of boreal mires of cryolithozone (51–52 N), in the Lower Amur region (Russia). String-flark fens are very similar to the aapa mires originally reported for the European North. The waterlogged minerotrophic central fen, with a ribbed surface pattern, is surrounded by oligotrophic bogs. The mosaic structure of the vegetation cover in the fens is determined by microtopography: mesooligotrophic dwarf shrub–herb–sphagnum strings, mesoeutrophic herb–sphagnum lawns, and sparse herb cover in water flarks. The flora, for the most part, corresponds with the European aapa, and has some characteristics of eastern features. We relate the localized evolution of string-flark complexes with water basin hydrology changes. The formation of string-flark complexes in pre-existing fens was preceded by the cessation of river flood waters over the surface of the mires. The further decline of erosion has led to the development of dwarf shrub–sphagnum communities containing microrelief. The immature strings of the aapa mires attest to the ongoing active change processes of the mires.

Ant colonization increased total mercury but reduced methylmercury contents in boreal mires, Northeast China

Soil macroinvertebrates as ecosystem engineers play significant, but largely ignored, roles in affecting mercury (Hg) cycle by altering soil physical-chemical properties. Ant is likely expanded into boreal mires with climate warming, however, its impacts on Hg cycle remained poorly understood. We compared total Hg (THg) and methylmercury (MeHg) contents in soils from antmounds (Lasius flavus) and the nearby ambient in a boreal mire in Northeast China. The present work seeks to unravel factors that controlling MeHg levels in case of ant appearance or absence. The average THg was 179 µg/kg in the ant mound and was 106.1 µg/kg in nearby soils, respectively. The average MeHg was 10.9 µg/kg in the ant mound and was 12.9 µg/kg in nearby soils, respectively. The ratios of MeHg to THg (%MeHg) were 7.61% in ant mounds and 16.75% in nearby soils, respectively. Ant colonization caused THg enrichment and MeHg depletion, and this change was obvious in the 10-20 cm depth soil layer where ants mainly inhabited. Spectrometry characteristics of soil dissolved organic matter (DOM) exert a stronger control than microorganisms on MeHg variation in soils. A structural equation model revealed that the molecular weight of DOM inhibited MeHg irrespective of ant presence or absence, while humification conducive to MeHg significantly in ant mound soils. Microorganisms mainly affected Hg methylation by altering the molecular weight and humification of DOM. We propose that the effects of ant colonization on MeHg rested on DOM feature variations caused by microorganisms in boreal mires.

Biodiversity of a boreal mire, including its hydrographic network (Shichengskoe mire, north-western Russia).

BackgroundThe paper is based on the dataset whose purpose was to deliver, in the form of GBIF-mediated data, diverse materials on the biodiversity of a large mire, Shichengskoe mire (Vologda Region, north-western Russia), including its various mire sites and intra-mire water bodies. The dataset was based on our materials collected for two decades (from 2000 to 2021) in different parts and biotopes of the Shichengskoe mire and complemented by scarce data obtained previously by other researchers. The data contain materials on the diversity of Animalia (2886 occurrences), Bacteria (22), Chromista (256), Fungi (111), Plantae (2463) and Protozoa (131). Within the study period, the most detailed and long-term biodiversity studies were carried out for higher plants and invertebrates. On the other hand, the data on the composition of lichens, protozoa, algae, basidiomycetes, some groups of invertebrates and, to a lesser extent, lichens and vertebrates are far less comprehensive and require further substantial research efforts. The list includes occurrences from both the peatland (mire sites and mire margins different in typology) and the objects of the mire hydrographic network. In a standardised form, this article summarises both already published (mainly in Russian) and unpublished materials.New informationThe paper summarises the results of long-term research on the biodiversity of a boreal mire, including its hydrographic network. A total of 5869 occurrences were included in the dataset published in the Global Biodiversity Information Facility (GBIF, gbif.org) for the first time. According to the GBIF taxonomic backbone, the dataset covers 1358 taxa, including 1250 lower-rank taxa (species, subspecies, varieties, forms) and 108 taxa identified to the genus level. Several species found in the Shichengskoe mire, mainly belonging to Bacteria, Chromista and Protozoa, have never been listed in GBIF for the territory of Russia before. The overwhelming majority of occurrences and identified species came from the territory of Shichengskiy Landscape Reserve. Due to our work, this Reserve is now the most studied regional reserve in the Vologda Region with respect to biodiversity. By the number of revealed species, it is close to two federal protected areas: Darwinskiy State Nature Biospheric Reserve and National Park "Russkiy Sever".

Carbon balance of a Finnish bog: temporal variability and limiting factors based on 6 years of eddy-covariance data

Abstract. Pristine boreal mires are known as substantial sinks of carbon dioxide (CO2) and net emitters of methane (CH4). Bogs constitute a major fraction of pristine boreal mires. However, the bog CO2 and CH4 balances are poorly known, having been largely estimated based on discrete and short-term measurements by manual chambers and seldom using the eddy-covariance (EC) technique. Eddy-covariance (EC) measurements of CO2 and CH4 exchange were conducted in the Siikaneva mire complex in southern Finland in 2011–2016. The site is a patterned bog having a moss–sedge–shrub vegetation typical of southern Eurasian taiga, with several ponds near the EC tower. The study presents a complete series of CO2 and CH4 EC flux (FCH4) measurements and identifies the environmental factors controlling the ecosystem–atmosphere CO2 and CH4 exchange. A 6-year average growing season (May–September) cumulative CO2 exchange of −61 ± 24 g C m−2 was observed, which partitions into mean total respiration (Re) of 167 ± 33 (interannual range 146–197) g C m−2 and mean gross primary production (GPP) of 228 ± 46 (interannual range 193–257) g C m−2, while the corresponding FCH4 amounts to 7.1 ± 0.7 (interannual range 6.4–8.4) g C m−2. The contribution of October–December CO2 and CH4 fluxes to the cumulative sums was not negligible based on the measurements during one winter. GPP, Re and FCH4 increased with temperature. GPP and FCH4 did not show any significant decline even after a substantial water table drawdown in 2011. Instead, GPP, Re and FCH4 were limited in the cool, cloudy and wet growing season of 2012. May–September cumulative net ecosystem exchange (NEE) of 2013–2016 averaged at about −73 g C m−2, in contrast with the hot and dry year 2011 and the wet and cool year 2012. Suboptimal weather likely reduced the net sink by about 25 g C m−2 in 2011 due to elevated Re, and by about 40 g C m−2 in 2012 due to limited GPP. The cumulative growing season sums of GPP and CH4 emission showed a strong positive relationship. The EC source area was found to be comprised of eight distinct surface types. However, footprint analyses revealed that contributions of different surface types varied only within 10 %–20 % with respect to wind direction and stability conditions. Consequently, no clear link between CO2 and CH4 fluxes and the EC footprint composition was found despite the apparent variation in fluxes with wind direction.

Quantifying trade-offs between ecological gains, economic costs, and landowners\u2019 preferences in boreal mire protection

Private land often encompasses biodiversity features of high conservation value, but its protection is not straightforward. Commonly, landowners’ perspectives are rightfully allowed to influence conservation actions. This unlikely comes without consequences on biodiversity or other aspects such as economic considerations, but these consequences are rarely quantitatively considered in decision-making. In the context of boreal mire protection in Finland, we report how acknowledging landowners’ resistance to protection changes the combination of mires selected to conservation compared to ignoring landowners’ opinions. Using spatial prioritization, we quantify trade-offs arising between the amount of landowners’ resistance, protected biodiversity, and financial costs in different conservation scenarios. Results show that the trade-offs cannot be fully avoided. Nevertheless, we show that the systematic examination of the trade-offs opens up options to alleviate them. This can promote the evaluation of different conservation policy outcomes, enabling better-informed conservation decisions and more effective and socially sustainable allocation of conservation resources.

Strong long-term interactive effects of warming and enhanced nitrogen and sulphur deposition on the abundance of active methanogens in a boreal oligotrophic mire

Peatlands play a key role in the carbon cycle by being a considerable source of atmospheric methane. Thus, an understanding of the microbial production of methane is important in relation to enviro ...

Some Aspects of the Systematics and Diagnostics of Peat Soils of Boreal Mires

On the basis of the review of available literature sources, the approaches to the systematics of peat soils in different soil classifications systems (Russian, German, FAO-UNESCO, WRB, and Soil Taxonomy) are discussed and compared with the landscape-based classifications of boreal mires. Among the diagnostic criteria, the most important in the systematics of peat soils and peatlands are the peat thickness, trophic status as the availability of nutrients and as a botanical concept, and acidity (pH) of peat and peat waters. The following suggestions are made: (a) to establish the peat thickness ≥30 cm as a criterion for peat soils, (b) to exclude the contents of nutrients in the peat from the diagnostic scheme for peat soils, and (c) to develop this scheme on the basis of geobotanical indicators. The latter may include active peat-forming plants, as well as plant species settling on the regressive mires under conditions of a cessation or drastic slowdown of peat accumulation. It is also recommended that the type of mesotrophic peat soils should be added to the Russian soil classification system and that the subtype of wet regressive soils should be distinguished within the oligotrophic type of peat soils along with the existing subtype of destructive soils.

Parameterisation of an integrated groundwater-surface water model for hydrological analysis of boreal aapa mire wetlands

Hydrological connections between aquifers and boreal mires need to be better understood for protection of this type of wetland. Three-dimensional (3D) models have so far been sparsely used for such systems. This study investigated the effect of parameterisation with global sensitivity analysis on groundwater-surface water (GW-SW) interactions in a boreal esker-aapa mire system. Sensitivity analysis by the elementary effect (Morris) method was applied to a 3D steady-state hydrological model built with the fully-integrated HydroGeoSphere code. Parameter sensitivity with respect to various model outputs was explored, providing comprehensive insights into the most hydrologically relevant parameters. The results indicated that depending on model outputs the most influential model parameters varied. They also revealed existence of feedback in terms of interdependence of parameters between the esker aquifer and surrounding aapa mires. The properties of the mire (or peatland) landscape affected groundwater levels in the unconfined aquifer and, conversely, esker-mire interactions depended on esker hydraulic characteristics. This implies that accurate representation of both systems is required and that reliable determination of GW-SW interactions may be impeded by parameter interactions. In this study, the van Genuchten functions were used to represent hydraulic properties of unsaturated flow domain and the results revealed that formal sensitivity analysis methods based on random sampling might not be appropriate for evaluating parametric sensitivity. If the van Genuchten parameters ranges are large, randomly sampled values may not always produce physically realistic water retention characteristics. Overall, our results demonstrate that the computationally efficient elementary effect method is a suitable tool for investigating the parametric sensitivity of integrated models, enhancing modelling of boreal groundwater-dependent ecosystems.

Predicting hotspots for threatened plant species in boreal peatlands

Understanding the spatial patterns of species distribution and predicting suitable habitats for threatened species are central themes in land use management and planning. In this study, we examined the geographic distribution of threatened mire plant species and identified their national hotspots, i.e. areas with high amounts of suitable habitats for threatened mire plant species. We also determined the main environmental correlates related to the distribution patterns of these species. The specific aims were to: (1) identify the environmental variables that control the distribution of threatened peatland species in a boreal aapa mire zone, Finland; and (2) to identify the richness patterns and hotspots of threatened species. Our results showed that the combination of individual species models offers a useful tool for identifying landscape-scale richness patterns for threatened plant species. The modeling performance was high across the modelled species, and the richness patterns generated by single models coincide with the expected richness pattern based on expert knowledge. The method is therefore a powerful tool for basic biodiversity applications. In cases where reliable models for species occurrences and hotspots can be produced, these models can play a significant role in land-use planning and help managers to meet different conservation challenges.

A Novel Approach for High-Frequency in-situ Quantification of Methane Oxidation in Peatlands

Methane (CH4) oxidation is an important process for regulating CH4 emissions from peatlands as it oxidizes CH4 to carbon dioxide (CO2). Our current knowledge about its temporal dynamics and contribution to ecosystem CO2 fluxes is, however, limited due to methodological constraints. Here, we present the first results from a novel method for quantifying in-situ CH4 oxidation at high temporal resolution. Using an automated chamber system, we measured the isotopic signature of heterotrophic respiration (CO2 emissions from vegetation-free plots) at a boreal mire in northern Sweden. Based on these data we calculated CH4 oxidation rates using a two-source isotope mixing model. During the measurement campaign, 74% of potential CH4 fluxes from vegetation-free plots were oxidized to CO2, and CH4 oxidation contributed 20 ± 2.5% to heterotrophic respiration corresponding to 10 ± 0.5% of ecosystem respiration. Furthermore, the contribution of CH4 oxidation to heterotrophic respiration showed a distinct diurnal cycle being negligible during nighttime while contributing up to 35 ± 3.0% during the daytime. Our results show that CH4 oxidation may represent an important component of the peatland ecosystem respiration and highlight the value of our method for measuring in-situ CH4 oxidation to better understand carbon dynamics in peatlands.

Changes in dissolved organic matter and microbial activity in runoff waters of boreal mires after restoration

A considerable proportion of boreal mires have been drained for soil amelioration purposes. In response to drainage-induced degradation, restoration practices have been implemented in recent decades. Restoration by raising the water level is often followed by changes in the quality of runoff waters, especially in concentrations of dissolved organic carbon (DOC), nitrogen (N) and phosphorus (total P, PO4-P). We studied how mire restoration affected bacterial production (BP), bacterial growth efficiency (BGE%) and respiration (R) in mire runoff waters from spruce swamps and Sphagnum pine bogs in south-central Finland. The quality of runoff water was monitored for 8 years (2008–2015) and bacterial activity was measured during 3 years (2010–2012) at runoff weir sites, including two pristine controls, one drained control and four treatment sites. The concentrations of DOC, N and P increased for 3–5 years after restoration. The increased availability of nutrients was followed by doubled BP (from ca. 0.34 to 0.88 µmol C L−1 d−1, averages of restored sites) and BGE% (from ca. 2.7 to 9.2%), whereas microbial respiration was only slightly increased. However, bacterial activity in mire waters was low compared with those generally measured in river and lake waters. This was presumably related to the recalcitrant quality of the mire-originated DOC, which was not clearly influenced by restoration. Dissolved organic matter (DOM) of low bioavailability contributes to browning of headwaters. As our study was focused only on short-term (1–5 years) effects, more research is needed for evaluating long-term impacts of peatland origin DOM on carbon fluxes, microbial activity and food webs of recipient aquatic ecosystems.

Selected properties of organic soils under boreal mire spruce forest in the Romincka Forest, NE Poland

Abstract The paper presents selected properties of the organic soils developed in boreal mire spruce forests (Sphagno girensohnii-Piceetum) in the Romincka Forest (NE Poland). Additionally, the relationship between soil fertility and forest stand productivity was investigated. Data from 12 soil profiles, differing in terms of peatland ecological type (raised bog, transitional bog and fen) was used. The significance of the differences in soil properties among peatland types was assessed with the Kruskal-Wallis test. Soil fertility was described using soil trophic index (SIGo), whereas stand productivity according to site index (SI) value. The properties of the analysed soils varied significantly in terms of peatland type. Soils from fens were more fertile (SIGo 25–31), less acidic (pH &gt; 5.7), with lower total potential acidity (36–40 cmol(+)·kg−1), higher base saturation (77–79%), Ca2+ content (116–136 cmol(+)·kg−1) and base exchange capacity (123–145 cmol(+)·kg−1) than soils from transition or raised bogs. No significant effect of soil fertility on the site index of stands growing on analysed soils was observed (r = 0.385, p = 0.216).

Relationship between aerodynamic roughness length and bulk sedge leaf area index in a mixed‐species boreal mire complex

AbstractLeaf area index (LAI) is an important parameter in natural ecosystems, representing the seasonal development of vegetation and photosynthetic potential. However, direct measurement techniques require labor‐intensive field campaigns that are usually limited in time, while remote sensing approaches often do not yield reliable estimates. Here we propose that the bulk LAI of sedges (LAIs) can be estimated alternatively from a micrometeorological parameter, the aerodynamic roughness length for momentum (z0). z0 can be readily calculated from high‐response turbulence and other meteorological data, typically measured continuously and routinely available at ecosystem research sites. The regressions of LAI versus z0 were obtained using the data from two Finnish natural sites representative of boreal fen and bog ecosystems. LAIs was found to be well correlated with z0 and sedge canopy height. Superior method performance was demonstrated in the fen ecosystem where the sedges make a bigger contribution to overall surface roughness than in bogs.

Simulated global warming increases usnic acid but reduces perlatolic acid in the mat-forming terricolous lichenCladonia stellaris

AbstractLichens as sessile and slow-growing symbiotic associations have evolved various carbon-based secondary compounds (CBSCs) to mitigate the effects of some stressors in the extreme environments in which they often grow. The mat-forming lichenCladonia stellaris, an important fodder for reindeer, produces usnic acid in the outermost layer and perlatolic acid in the medulla. Here, we studied effects of simulated global warming on these CBSCs inC. stellariscultivated in climate chambers with: 1) ambient conditions as control or 2) ambient conditions +4°C. The chambers simulated, at an hourly resolution, an averaged 10-year growing season dynamic from a long-term monitored boreal mire in northern Sweden. After two months of acclimation, +4°C warming in one simulated growing season increased the concentration of usnic acid by 31% compared with ambient conditions, whereas the warming decreased the concentration of perlatolic acid by 14%. Since lichen CBSCs play important roles in ecosystem processes such as lichenivory and decomposition, these changes may profoundly affect lichen-dominated ecosystems.

Effects of warming and increased nitrogen and sulfur deposition on boreal mire geochemistry

Boreal mire ecosystems are predicted to experience warmer air temperatures as well as changed deposition loads of nitrogen and sulfur during the coming century. In this study, we hypothesized that vegetation changes that accompany these new environmental conditions alter the chemical composition of peat. To test this hypothesis, we quantified changes in peat geochemistry (Al, Ca, Fe, Mg, Na, P, Pb, and Zn) that have occurred in field manipulation plots exposed to 12 years of warming and nitrogen and sulfur additions in a nutrient-poor boreal mire. In contrast to non-nutrients with a mainly atmospheric origin (i.e. Pb), Al-normalized inventories of micronutrients (Zn and Fe) and macronutrients (P and Ca) were significantly (P < 0.05) higher as a result of warming. For P and Ca, enrichments were also induced by nitrogen additions alone. These results suggest that mires evolving under increasing temperatures and availability of nitrogen are around two times more effective in storing nutrients in the accumulating peat. Our study provides the first empirical evidence that predicted changes in climate and nitrogen deposition scenarios will increase the retention of Ca, Fe, P, and Zn in surface peat of boreal mires in the near future, which may cause a depletion of nutrients released to inland waters dependent on mire inputs.

Rapid recovery of invertebrate communities after ecological restoration of boreal mires

Mire degradation due to drainage for forestry results in the loss of mire specialist species. To halt the loss in biodiversity, ecological restoration is needed and already implemented. However, a major challenge in ecological restoration is whether actions taken have the desired outcome. Key abiotic and biotic conditions for the successful restoration of invertebrate communities can be identified by testing the “Field of Dreams” hypothesis, which postulates that if a habitat is successfully restored, species will return. This study was conducted in nine boreal mires located in Eastern Finland, 1–3 years after restoration. Parts of each mire were drained for forestry during the 1960s and 1970s, and restored in 2003–2006. Two 250 m transects were established in each of three treatments (pristine, drained, restored) per mire. We used pitfall trapping to sample carabid beetles and spiders, sweep netting to sample micromoths and crane flies and counts along the transects to sample macromoths. Vegetation cover, water table level, and climatic variables were measured along all transects. Mire specialist species and invertebrate communities responded positively to restoration and negatively to drainage, whereas generalists showed varied responses. In addition, mire specialists were associated with high cover of Sphagnum mosses and with low numbers of tall trees (&gt;3 m). Therefore, to successfully restore populations and communities of mire specialist invertebrates, maintaining environmental conditions that favor the growth of Sphagnum mosses, rewetting the sites and removing larger trees are necessary measures.