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Here, we report on an archaeobotanical study of charred wood remains from eight iron spearhead sockets from a sacrificial aquatic site at Nidajno/Czaszkowo 1, Mazurian Lakeland, NE Poland (c. second–fifth c. CE), in search of botanical evidence for the selection of wood for manufacture of wooden shafts used with iron spearheads. The samples were analysed using a Nicon Eclipse ME600 metallographic microscope. The results show significant botanical data for Fraxinus excelsior L. and Tillia sp.The results of this research illustrate the material standard of the finds from a unique sacrificial site of the Scandinavian ‘sacrificial bog’ type, such as the sacrificial site at Nidajno/Czaszkowo 1—one of the most scientifically prospective in the entire zone of the North European Barbaricum. They also reveal a clear preference in the way spears and javelins were made, linked to the use of ash wood for this purpose. This choice is rational, justified by the technological and operational properties of this type of wood, but it also has connotations from the world of symbolic religious imagery. [ABSTRACT FROM AUTHOR]

The rising global temperature makes understanding the impact of warming on plant physiology in critical ecosystems essential, as changes in plant physiology can either help mitigate or intensify climate change. The northern peatlands belong to the most important parts of the global carbon cycle. Therefore, knowledge of the ongoing and future climate change impacts on peatland vegetation photosynthesis is crucial for further refinement of peatland or global carbon cycle and vegetation models. As peat moss (Sphagnum spp.) and bog cranberry (Vaccinium oxycoccos L.) represent some of the most common plant functional groups of peatland vegetation, we examined the impact of experimental warming on the status of their photosynthetic apparatus during the early vegetation season. We also studied the differences in the winter to early spring transition of peat moss and bog cranberry photosynthetic activity. We have shown that peat moss starts photosynthetic activity earlier because it relies on light-dependent energy dissipation through the winter. However, bog cranberry needs a period of warmer temperature to reach full activity due to the sustained, non-regulated, heat dissipation during winter, as suggested by the doubling of photosystem II efficiency and 36% decrease in sustained heat dissipation between the mid-March and beginning of May. The experimental warming further enhanced the performance of photosystem II, indicated by a significant increase in the photosystem II performance index on an absorption basis due to warming. Therefore, our results suggest that bog cranberry can benefit more from early spring warming, as its activity is sped up more compared to peat moss. This will probably result in faster shrub encroachment of the peatlands in the warmer future. The vegetation and carbon models should take into account the results of this research to predict the peatland functions under changing climate conditions. [ABSTRACT FROM AUTHOR]

Land-use changes and anthropogenic disturbances are major threats to biodiversity, affecting ecosystem function and recovery. In boreal Alberta, Canada, petroleum development has led to extensive landscape fragmentation, notably through linear clearings created for seismic exploration that remove surface vegetation and microtopography. Despite partial recovery on forested seismic lines, peatland recovery is often arrested, impacting wildlife and carbon dynamics. Restoration efforts employ silviculture techniques to create microtopography and foster tree growth, but the efficacy of restoration treatments in restoring peatland plant diversity remains uncertain. We compared taxonomic, phylogenetic, and functional diversity of understory plant communities across treated and untreated seismic lines, alongside reference sites in treed bogs and fens. Treated lines generally had a twofold increase in plant height, leaf dry matter content, and foliar nitrogen and phosphorus contents compared to reference sites. In bogs, treated lines differed from reference conditions driven by increases in herbaceous taxa, while fens displayed disparities mainly in taxonomic and phylogenetic diversity. Differential responses of bogs and fens underline the necessity for tailored management strategies. Changes in plant diversity away from restoration targets have implications for ecosystem recovery, emphasizing the importance of long-term monitoring to evaluate the effectiveness of silviculture techniques in restoring boreal peatland plant communities. [ABSTRACT FROM AUTHOR]

Soil respiration (SR) is one of the largest fluxes in the global carbon cycle, exceeding anthropogenic CO2 emission by more than an order of magnitude. Estimation of the heterotrophic component of SR is necessary to assess the carbon balance on the ecosystem and on the regional, national, and global scales. Within the framework of the most important national innovation project "Development of a System of Ground-based and Remote Monitoring of Carbon Pools and Greenhouse Gas Fluxes on the Territory of the Russian Federation," the first Russian national network is organized to monitor CO2 emission from soils and other linked parameters. The SR values and the relationship with the temperature of the upper 5- to 10-cm layer of soil (TS) are analyzed for the first time on the territory of Russia based on methodologically identical field measurements conducted simultaneously in the summer period (June–August 2023) at 75 monitoring sites in the different ecosystems in the main Russian bioclimatic zones from the tundra to the semidesert. The positive effect of soil temperature on the mean summer SR rate and the maximum monthly SR values is observed in the interval of mean TS from 10 to 20°C. Among the ecosystems studied, the lowest SR values are recorded in tundra and bog ecosystems, while the highest values are in the forest–steppe. Amongst the forest ecosystems, the lowest SR rates are characteristic of larch forests, while the highest SR values are observed in broadleaved forests of the forest–steppe zone. To clarify the regularities obtained, it is necessary to expand studies in all bioclimatic zones, but mainly in agrocenoses, tundra, and steppe ecosystems. [ABSTRACT FROM AUTHOR]

Summary: This paper reconstructs the population dynamics within the Hyllie Mosse region (Scania, Sweden) from 2400 to 1600 BC. South‐western Scania is particularly well‐known thanks to extensive archaeological work in the past decades, making it one of the most thoroughly investigated areas in Sweden. The Late Neolithic and Early Bronze Age periods are of paramount importance in understanding the socio‐cultural transformations within the Baltic region. By integrating a comprehensive database of longhouses from Scania with the available archaeological data from the Hyllie Mosse area, this study provides absolute demographic estimates through a transparent and replicable methodology. It highlights that the region experienced a significant peak in human occupation between 2000 and 1800 BC, followed by a decline. In prehistoric times, the area was covered by a relatively large bog, and was therefore not uniformly settled. At its peak, it is estimated that the region, approximately 9.7 km2 in size – 4 km2 of which have been archaeologically investigated – could have supported 75 to 150 inhabitants. [ABSTRACT FROM AUTHOR]

Bog and lake ecosystems of the boreal region are recognized as important parts of the global biogeochemical carbon cycle. At the same time, many aspects of the gas regime dynamics of bog lakes remain understudied. The paper presents data on the seasonal dynamics of dissolved CH4 and CO2 concentrations in the bog lake located in the ridge-lake complex of the Ilassky bog, a typical raised bog in the northern taiga of northwestern Russia, and results of analysis of the seasonal vertical distribution of greenhouse gases in the water column and the dynamics of surface concentrations with increased time resolution. The reasons for and patterns of their variability are considered, including those in relation to the characteristics of the bottom sediments. Concentrations of CH4 and CO2 in the water column vary during the year within wide ranges: from 4 to 652 µg/L and from 0.19 to 19 mg/L, respectively. CH4 concentrations in the surface layer are at approximately the same level from May through August, with values measured in the water (5.9 to 11 µg/L) more than one hundred times higher than the concentrations in equilibrium with the atmosphere (0.04 to 0.05 µg/L), indicating a methane flux to the atmosphere. The CO2 concentrations decrease throughout the open water period and become lower than the equilibrium concentrations with the atmosphere by the end of August, indicating a change in the flux direction and uptake of CO2 from the atmosphere. The results showed that, depending on the season, a bog lake can be not only a source but also a sink for atmospheric carbon, 90–99% of which is CO2 according to literature data. [ABSTRACT FROM AUTHOR]

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Direct sewage discharge may enhance soil nitrous oxide (N2O) emissions, worsening the greenhouse effect. However, the effects of sewage discharge into bogs on N2O flux, drivers and influencing mechanisms remain unclear. Additionally, investigating the impact of reclaimed water on N2O flux is important for bog replenishment and water shortage alleviation. This study simulated sewage from different sources into a bog and analyzed N2O fluxes, soil (organic carbon, total nitrogen, ammonium nitrogen, nitrate nitrogen, total phosphorus, available phosphorus, pH and electrical conductivity), plant (species richness and biomass) and microorganisms (ammonia-oxidizing archaea, napA , nirS , nirK and nosZ genes). Results showed that the reclaimed water did not significantly change N2O flux, while 50% tap water mixed with 50% domestic sewage and domestic sewage significantly increased the N2O flux. Among soil factors, available nitrogen and pH were key in influencing N2O flux. Among plant parameters, species richness was the primary factor affecting N2O flux. Nitrogen transformation functional genes contributed the most to the increase in the N2O fluxes, with an increase in domestic sewage input leading to a higher abundance of these genes and subsequent N2O emissions. Therefore, domestic sewage should be considered, as it significantly increases N2O emissions by affecting the soil, plants and microorganisms, thereby increasing the global warming potential. This study's findings suggest that using treated reclaimed water for bog replenishment could be an environmentally friendly approach to wetland management. [ABSTRACT FROM AUTHOR]

The main objective of the study was to evaluate the population characteristics of Betula nana under different anthropogenic influences. The study was conducted in the vicinity of the exploited Šepeta peatland (northeastern Lithuania). The population status of B. nana was determined by comparing the ramet density and morphology (height, branching, and leaf size), the age structure, the number of generative ramets, and their flowering characteristics in four study areas at different distances from the exploited peatlands and in different habitats. Around 20 environmental factors were included in the analysis, covering water levels, peat, and vegetation characteristics. Shading, drainage and increased amounts of nitrogen in the habitats are the main factors contributing to the differences and structure of B. nana cenopopulations. Although taller ramets with larger leaves are observed under the changed conditions as an adaptation to shading, the negative anthropogenic effects in the most affected habitats are reflected in a reduction in the number of flowering ramets, lower vegetative regeneration, and an increase in the number of dead twigs on mature ramets. [ABSTRACT FROM AUTHOR]

Peat particulate organic matter (POM) in the anoxic subsurface of peatlands is increasingly recognized as an important terminal electron acceptor (TEA) in anaerobic respiration. While POM reduction has been demonstrated in laboratory peat‐soil incubations and (electro‐) chemical reduction assays, direct demonstration of POM reduction in peat soils under in situ, field conditions involving quantification of transferred electrons remain missing. Herein, we demonstrate that deployment of an oxidized reference POM in the anoxic, methanogenic subsurface of three ombrotrophic bogs, followed by one year incubation, resulted in the transfer of approximately 150–170 μmol of electrons per gram POM to the deployed reference POM. The capacity of this reduced POM to accept electrons was partially restored upon subsequent exposure to dissolved oxygen. These findings provide direct evidence for POM acting as regenerable and sustainable TEA for anaerobic respiration in temporarily anoxic parts of peat soils. Based on the number of electrons transferred to POM and thermodynamic considerations, we estimate that anaerobic respiration to POM may largely suppress methanogenesis in peat soils, particularly close to the oxic‐anoxic interface across which POM is expected to undergo redox cycling. Plain Language Summary: In oxygen‐depleted peat soil, microbes slowly break down peat material to CO2 in a series of processes summarized under the term anaerobic respiration. These processes have in common that they require a chemical substance to which microbes can transfer electrons liberated in anaerobic respiration. Previous studies provided evidence that peat particulate organic matter (POM), the organic material primarily making up peat soils, can act as this electron acceptor. In this work, we buried a reference POM, placed in small mesh bags, in three Swedish peat soils. After 1 year, analysis of the recollected POM indeed showed that it had taken up electrons. Some of these electrons could be subsequently removed from the POM by bringing it in contact with dissolved oxygen. Taken together, our study supports that POM in peatlands accepts electrons, temporarily stores them, and then transfers them to oxygen when it becomes available. In this role of electron acceptor, POM may significantly decrease the formation of large amounts of methane, a gas that, when released from peatlands, largely contributes to warming of the atmosphere. Electron transfer to POM in peatland soils thus may play an important and desirable role in lowering natural methane release from peatland ecosystems. Key Points: Oxidized reference peat particulate organic matter (POM) was reduced in the anoxic subsurface of three ombrotrophic bogs over 1 yearOn average, 160 μmol electrons were transferred per gram reference POM across the three bogsThe reduced POM was partially re‐oxidized by dissolved oxygen, supporting that POM is a sustainable terminal electron acceptor [ABSTRACT FROM AUTHOR]

The environmental filtering hypothesis predicts that abiotic factors restrict communities by selecting species capable of survival and persistence under specific conditions, resulting in variations in beta diversity, phylogenetic clustering, and niche differentiation among communities when studying environmental gradients. Cushion bogs and high-altitude wetlands along the Andes display homogeneous flora contrasting with zonal vegetation. Despite being influenced by microclimatic conditions, these ecosystems are subject to diverse environmental effects. Here, we test the environmental filtering hypothesis on the structure of cushion bog communities along a broad-scale latitudinal gradient from 15° S to 42° S. We analyzed 421 bogs and 293 species across three macroclimatic regions with distinct summer, winter, and transitional arid rainfall regimes. Using variance partitioning and membership-based regionalization models, we examined the impacts of climatic, edaphic, and spatial variables on beta diversity. We also assessed species' niche overlap and the influence of environmental filters on the communities' phylogenetic diversity. Results show that species turnover and niche overlap vary with macroclimatic differences, delineating three distinct regions. Notably, phylogenetic clustering in the driest part of the gradient (23° S–24° S) highlights the impact of environmental filtering. Aridity and temperature variations at a broad scale serve as environmental filters shaping the composition of bog communities across southern South America. [ABSTRACT FROM AUTHOR]

The studies were carried out on the territory of the Kindasovo forest-bog research station of the Karelian Research Center, Russian Academy of Sciences, located in the middle taiga subzone (61°48′ N and 33°35′ E). The experiments were carried out in the Nenazvannoe natural mesoeutrophic bog of the aapa type in seven permanent bog areas located in different ecological and coenotic conditions. The paper presents long-term results (from 10 to 38 years) of studies of the dynamics of annual growth of 11 widespread hygro- and hydrophilic species of sphagnum mosses. Based on fluctuations in the average annual growth data during the years of study, the largest increases were observed for Sphagnum riparium (140 mm) and S. obtusum (93 mm), growing in heavily watered bog areas and not withstanding drying out; medium growths of S. fallax (65 mm), S. subsecundum (57 mm), S. majus (42 mm), S. balticum (36 mm), and S. warnstorfii (28 mm) are found in low-flow watered bogs, hollows, and on carpets; the lowest growth was shown for S. divinum (17 mm), S. centrale (15 mm), S. papillosum (12 mm), and S. fuscum (8 mm), growing on ridges, low hummocks, and carpets under conditions of sharply variable conditions hydration. A correlation analysis to study the influence of precipitation and average temperature on the annual growth of sphagnum mosses did not show any significant dependence of moss growth on temperature during the growing season. For S. fuscum, S. obtusum, and S. warnstorfii, negative dependences on the temperature of individual months are observed in different months of the growing season. Precipitation during the growing season is the main factor determining the dependence of the annual growth of sphagnum mosses. A significant dependence of annual growth on precipitation during the growing season was shown for species S. obtusum, S. papillosum, S. centrale, S. fallax, and S. subsecundum, while the significance was weak for S. divinum, S. fuscum, and S. majus. [ABSTRACT FROM AUTHOR]

Restorations of former cranberry farms ("bogs") aim to re-establish native wetland vegetation, promote cold water habitat, and attenuate nitrogen (N) delivery to coastal waters. It is unclear, though, how elements of restoration design such as microtopography, groundwater interception, and plant communities affect N removal via denitrification. In a recently restored riparian cranberry bog with created microtopography, we compared denitrification potential, nitrous oxide (N2O) yield of denitrification (ratio of N2O:N2O + N2 gases), in situ N2O fluxes, soil chemistry, and plant communities at the highest and lowest elevations within 20 plots and at four side-channel groundwater seeps. Denitrification potential was > 2 × greater at low elevations, which had plant communities distinct from high elevations, and was positively correlated with plant species richness (Spearman's rho = 0.43). Despite detecting high N2O yield (0.86 ± 0.16) from low elevation soils, we observed small N2O emissions in situ, suggesting minimal incomplete denitrification even in saturated depressions. Groundwater seeps had an order of magnitude higher denitrification potentials and 100–300 × greater soil NO3− concentrations than the typically saturated low elevation soils. Groundwater seeps also had high N2O yield (1.05 ± 0.15) and higher, but spatially variable, in situ N2O emissions. Our results indicate that N removal is concentrated where soils interact with NO3–rich groundwater, but other factors such as low soil carbon (C) also limit denitrification. Designing restoration features to increase groundwater residence time, particularly in low lying, species rich areas, may promote more N attenuation in restored cranberry bogs and other herbaceous riparian wetlands. [ABSTRACT FROM AUTHOR]

Odonates are widely considered to be bioindicators of freshwater habitat quality. Somatochlora arctica (Corduliidae) is commonly found across Eurasia, predominantly in North and Central Europe, but in the UK, it has a restricted range and is listed as near threatened despite a large, potential habitat availability. Across their range, larvae are found in Sphagnum-filled bog pools near coniferous woodlands, but detailed data on their habitat requirements are limited and often overlooked in favour of adult surveys which inhibits conservation efforts. This study surveyed three areas across Scotland: Abernethy & Loch Garten National Nature Reserve (NNR), Beinn Eighe NNR and Flanders Moss NNR, to evaluate how different environmental factors per pool (e.g. water depth and chemistry, Sphagnum coverage, woodland distance, etc.) affect the presence of S. arctica larvae. We found a higher occurrence of S. arctica larvae when pools were located close to woodlands (i.e. 0–10 m), and had high coverage of Sphagnum (> 90%). Environmental variables in pools surveyed (i.e. conductivity, water depth, pH and water temperature) had no significant effects on S. arctica presence. Implications for insect conservation: Our results highlight and discuss the importance of nearby woodlands and Sphagnum cover for S. arctica larvae. Future conservation projects should consider the proximity of woodland to current and restored S. arctica sites or promoting expansion of surrounding natural woodland patches to benefit S. arctica and potentially other odonates sharing similar ecological preferences. [ABSTRACT FROM AUTHOR]

The harvesting of living peat moss (Sphagnum spec.) for various industrial applications has become increasingly prevalent. The harvesting process involves manual or mechanical extraction of Sphagnum fragments with minor to significant alterations of the habitats. This study investigates the impact of Sphagnum harvesting on arthropod fauna and vegetation structure at two donor sites with small-scale Sphagnum harvest in northwestern Germany. In the first year after the harvest, comparative surveys were carried out between harvested and unharvested reference areas. Arthropods living in and on the upper Sphagnum layer were studied by manually extracting quadrat samples. Vegetation surveys focused on the vascular plant composition and Sphagnum layer thickness as key habitat parameters. Results indicate no substantial effects on the total numbers for most arthropod orders. In contrast, the frequency of ant workers and the number of ant nests were considerably lower in harvested areas compared to reference areas. Vegetation analysis revealed that the shortening of the Sphagnum hummocks led to a homogenization of the vegetation structure and alterations in species composition in favor of moisture-loving species. Although no significant effects on total beetle populations were observed, the abundance of bog generalists and specialists was significantly reduced in harvest areas. Certain species displayed preferences for harvested or reference areas. Future harvesting practices should consider preserving vulnerable arthropod species and restricting harvesting to a small scale to mitigate adverse effects on bog ecosystems. [ABSTRACT FROM AUTHOR]

Peatlands, constituting over half of terrestrial wetland ecosystems across the globe, hold critical ecological significance and are large stores of carbon (C). Irish oceanic raised bogs are a rare peatland ecosystem offering numerous ecosystem services, including C storage, biodiversity support and water regulation. However, they have been degraded over the centuries due to artificial drainage, followed by peat extraction, afforestation and agriculture. This has an overall negative impact on the functioning of peatlands, shifting them from a moderate C sink to a large C source. Recognizing the importance of these ecosystems, efforts are underway for conservation (rewetting and rehabilitation), while accurately accounting for C stock and greenhouse gas (GHG) emissions. However, the implementation of these efforts requires accurate identification and mapping of artificial drainage ditches. This study utilized very high‐resolution (25 cm) aerial imagery, and a deep learning (U‐Net) approach to map the visible artificial drainage (unobstructed by vegetation or infill) in raised bogs at a national scale. The results show that artificial drainage is widespread, with ~20 000 km of drains mapped. The overall accuracy of the model was 80% on an independent testing dataset. The data were also used to derive the Fracditch which was 0.03 (fraction of artificial drainage on industrial peat extraction sites). This is lower than IPCC Tier 1 Fracditch and can aid in IPCC Tier 2 reporting for Ireland. This is the first study to map drains with diverse sizes and patterns on Irish‐raised bogs using optical aerial imagery and deep learning methods. The map will serve as an important baseline dataset for evaluating the artificial drainage ditch conditions. It will prove useful for sustainable management, conservation and refined estimations of GHG emissions. The model's capacity for generalization implies its potential in mapping artificial drains in peatlands at a regional and global scale, thereby enhancing the comprehension of the global effects of artificial drainage ditches on peatlands. [ABSTRACT FROM AUTHOR]

Peatlands in the Canadian boreal forest are being negatively impacted by anthropogenic climate change, the effects of which are expected to worsen. Peatland types and sub‐classes vary in their ecohydrological characteristics and are expected to have different responses to climate change. Large‐scale modelling frameworks such as the Canadian Model for Peatlands, the Canadian Fire Behaviour Prediction System and the Canadian Land Data Assimilation System require peatland maps including information on sub‐types and vegetation as critical inputs. Additionally, peatland class and vegetation height are critical variables for wildlife habitat management and are related to the carbon cycle and wildfire fuel loading. This research aimed to create a map of peatland sub‐classes (bog, poor fen, rich fen permafrost peat complex) for the Canadian boreal forest and create an inventory of peatland vegetation height characteristics using ICESat‐2. A three‐stage hierarchical classification framework was developed to map peatland sub‐classes within the Canadian boreal forest circa 2020. Training and validation data consisted of peatland locations derived from various sources (field data, aerial photo interpretation, measurements documented in literature). A combination of multispectral data, L‐band SAR backscatter and C‐Band interferometric SAR coherence, forest structure and ancillary variables was used as model predictors. Ancillary data were used to mask agricultural areas and urban regions and account for regions that may exhibit permafrost. In the first stage of the classification, wetlands, uplands and water were classified with 86.5% accuracy. In the second stage, within the wetland areas only, peatland and mineral wetlands were differentiated with 93.3% accuracy. In the third stage, constrained to only the peatland areas, bogs, rich fens, poor fens and permafrost peat complexes were classified with 71.5% accuracy. Then, ICESat‐2 ATL08 spaceborne lidar data were used to describe regional variations in peatland vegetation height characteristics and regional and class‐wise variations based on a boreal forest wide sample. This research introduced a comprehensive large‐scale peatland sub‐class mapping framework for the Canadian boreal forest, presenting the first moderate resolution map of its kind. [ABSTRACT FROM AUTHOR]

"The History of Climate Change: Reflections on History of Climate Change: From the Earth's Origins to the Anthropocene" by Antonello Provenzale provides a comprehensive account of Earth's climate over the past 4.5 billion years. The book explores the roles of atmospheric and oceanic warming and cooling, the impact of greenhouse gases and glaciations, and the emergence of life. Provenzale's expertise sheds light on the ecological conditions that have allowed for adaptation and resilience throughout Earth's history. The book also discusses the collapse of the Conger ice shelf in East Antarctica in 2022 and emphasizes the unprecedented acceleration and global scale of current climate change. It concludes by urging for collective action to address the devastating consequences of climate change. [Extracted from the article]

Permafrost thaw in northern peatlands causes collapse of permafrost peat plateaus and thermokarst bog development, with potential impacts on atmospheric greenhouse gas exchange. Here, we measured methane and carbon dioxide fluxes over 3 years (including winters) using static chambers along two permafrost thaw transects in northwestern Canada, spanning young (~30 years since thaw), intermediate and mature thermokarst bogs (~200 years since thaw). Young bogs were wetter, warmer and had more hydrophilic vegetation than mature bogs. Methane emissions increased with wetness and soil temperature (40 cm depth) and modelled annual estimates were greatest in the young bog during the warmest year and lowest in the mature bog during the coolest year (21 and 7 g C‐CH4 m−2 year−1, respectively). The dominant control on net ecosystem exchange (NEE) in the mature bog (between +20 and −54 g C‐CO2 m−2 year−1) was soil temperature (5 cm), causing net CO2 loss due to higher ecosystem respiration (ER) in warmer years. In contrast, wetness controlled NEE in the young and intermediate bogs (between +55 and −95 g C‐CO2 m−2 year−1), where years with periodic inundation at the beginning of the growing season caused greater reduction in gross primary productivity than in ER leading to CO2 loss. Winter fluxes (November–April) represented 16% of annual ER and 38% of annual CH4 emissions. Our study found NEE of thermokarst bogs to be close to neutral and rules out large CO2 losses under current conditions. However, high CH4 emissions after thaw caused a positive net radiative forcing effect. While wet conditions favouring high CH4 emissions only persist for the initial young bog period, we showed that continued climate warming with increased ER, and thus, CO2 losses from the mature bog can cause net positive radiative forcing which would last for centuries after permafrost thaw. [ABSTRACT FROM AUTHOR]

International Atomic Energy Agency (IAEA) is the leading international organization in the field of nuclear energy and nuclear non-proliferation. This paper examines the most important policy body of the Agency, the Board of Governors (BoG). The legal foundation of the BoG will be discussed in light of its constitutional documents, most notably the Statute of the IAEA and the Rules of Procedure of the BoG. The research question will be approached from the theoretical angle of functionalism. The paper suggests that in fact, the practical role of the BoG is even more important than could be concluded on the basis of the legal documents whence the powers of the BoG derive. Over the years, the normative framework of the IAEA has enabled the BoG to adapt to rapidly changing decision-making environments and political situations. Furthermore, this has made it possible for the BoG to contribute in a relatively effective manner to the development of substantive international nuclear policy and law. [ABSTRACT FROM AUTHOR]

Northern peatlands are a globally significant source of methane (CH4), and emissions are projected to increase due to warming and permafrost loss. Understanding the microbial mechanisms behind patterns in CH4 production in peatlands will be key to predicting annual emissions changes, with stable carbon isotopes (δ13C‐CH4) being a powerful tool for characterizing these drivers. Given that δ13C‐CH4 is used in top‐down atmospheric inversion models to partition sources, our ability to model CH4 production pathways and associated δ13C‐CH4 values is critical. We sought to characterize the role of environmental conditions, including hydrologic and vegetation patterns associated with permafrost thaw, on δ13C‐CH4 values from high‐latitude peatlands. We measured porewater and emitted CH4 stable isotopes, pH, and vegetation composition from five boreal‐Arctic peatlands. Porewater δ13C‐CH4 was strongly associated with peatland type, with δ13C enriched values obtained from more minerotrophic fens (−61.2 ± 9.1‰) compared to permafrost‐free bogs (−74.1 ± 9.4‰) and raised permafrost bogs (−81.6 ± 11.5‰). Variation in porewater δ13C‐CH4 was best explained by sedge cover, CH4 concentration, and the interactive effect of peatland type and pH (r2 = 0.50, p < 0.001). Emitted δ13C‐CH4 varied greatly but was positively correlated with porewater δ13C‐CH4. We calculated a mixed atmospheric δ13C‐CH4 value for northern peatlands of −65.3 ± 7‰ and show that this value is more sensitive to landscape drying than wetting under permafrost thaw scenarios. Our results suggest northern peatland δ13C‐CH4 values are likely to shift in the future which has important implications for source partitioning in atmospheric inversion models. Plain Language Summary: Peatlands are abundant across the boreal‐Arctic landscape and are important sources of methane, a powerful greenhouse gas. The amount of methane emitted into the atmosphere depends on multiple factors including the organic material being decomposed and the microbial processes ("pathways") that produce methane. The different pathways of methane production leave distinct fingerprints ("stable carbon isotopes") on methane that provide information on how that methane was formed and help to trace methane in the atmosphere back to its ground source. We looked at how stable carbon isotopes change across five northern peatland locations and wanted to know what controls those changes. We found that stable carbon isotopes differ between bogs and fens and are further controlled by soil pH and the abundance of sedge vegetation present. We used this information to test how stable carbon isotopes from northern peatlands might change as the landscape becomes wetter or drier due to the impacts of climate change. We found that peatland stable carbon isotopes are most sensitive to potential landscape drying opposed to wetting which has important implications for improving methane emission models. Key Points: Porewater δ13C‐CH4 values of northern bogs and fens differ from each other and correlate with emitted δ13C‐CH4 valuesIn addition to peatland type, vascular plant cover, pH, and CH4 concentration help explain variation in porewater δ13C‐CH4 valuesThe δ13C‐CH4 value for northern peatlands is more sensitive to landscape drying than wetting under permafrost thaw scenarios [ABSTRACT FROM AUTHOR]

Specific yield affects how much the water table rises and falls in response to rainfall, to evaporation and to seepage gains and losses. It also affects the aeration of the soil above the water table. Although widely measured in peat soils, the effect of wetting history on its value has not been investigated. Specific yield has been estimated in many studies by cutting peat cores into layers, and measuring how much water drains from the individual layers after they have been wetted. Specific yield, however, is a phenomenon of the soil profile and not subsections, so this method may not provide a reliable estimate of its value. Few studies have reported on the effect of botanical composition on specific yield, or at least have not controlled for the effect by keeping other peat properties like degree of humification constant. We addressed these questions by measuring specific yield in intact cores of peat in a series of laboratory experiments. Two common but contrasting types of Sphagnum peat were investigated that had similar degrees of humification: Sphagnum medium peat and Sphagnum pulchrum peat. We found that specific yield was highly variable, ranging between 0.16 and 0.62. Specific yield was not affected by wetting history, but was significantly different between the peat types, being on average 0.21 higher in the S. pulchrum cores. Specific yield did not vary with depth in the S. medium cores but declined linearly with depth at a rate of 0.018 per cm in the Sphagnum pulchrum cores. Finally, we found that drainage from the peat profile above the zone through which the water table falls is an important component of specific yield, contributing more than 66%–91% of its value in the S. pulchrum peat. Our results show that wetting history probably does not need to be accounted for when estimating specific yield, although further work on this potential effect is recommended. Our work highlights the importance of measuring specific yield using intact cores (field methods may also be appropriate) and suggests that many previous peatland studies may have underestimated its value. [ABSTRACT FROM AUTHOR]

The endangered bog turtle (Glyptemys muhlenbergii) exemplifies issues related to rare species conservation; presence surveys have low detection and variables used in habitat models can lack relevance to established biological relationships of the species to its environment. The species' use of groundwater saturated soils and stream networks as core habitat and dispersal corridors has been documented. Less is known about the landscape factors that promote the formation and persistence of wetlands used for core habitat.A GIS‐based resource selection function was developed to predict bog turtle habitat use. Trained on 1 ha plots centred on occupied sites and pseudo‐absent plots constrained to areas within 56.4 m to stream network centrelines, the model tested the capacity of a topographic wetness index (TWI), stream order and soil, wetland and land cover type to predict the presence of suitable habitat and turtle occupancy. Landscape variables were sampled at 10 m resolution, but variable selection and model performance were analysed at 100 m resolution to maintain a biologically relevant 1 ha habitat scale and accommodate the resolution of other variables.Suitable habitat and turtle presence were best predicted by intermediate to high values of TWI, land cover with low vegetation height and wetlands, second‐ and third‐order streams and the occurrence of mapped National Wetland Inventory polygons and hydric soils. Very high values of TWI were negatively associated with habitat suitability. The area under the curve of the best model was 0.833.Suitable habitat was found on 88% of 55 independent sites selected using the model and nine new occupied sites were confirmed. Model error is discussed with consideration of human‐altered drainage networks on the agricultural landscape. [ABSTRACT FROM AUTHOR]

Peatland restoration and rehabilitation action has become more widely acknowledged as a necessary response to mitigating climate change risks and improving global carbon storage. Peatland ecosystems require restoration time spans of the order of decades and, thus, cannot be dependent upon the shorter-term monitoring often carried out in research projects. Hydrological assessments using geospatial tools provide the basis for planning restoration works as well as analysing associated environmental influences. "Restoration" encompasses applications to pre-restoration and post-restoration scenarios for both bogs and fens, across a range of environmental impact fields. The aim of this scoping review is to identify, describe, and categorize current process-based modelling uses in peatlands in order to investigate the applicability and appropriateness of ecohydrological and/or hydrological models for northern peatland restoration. Two literature searches were conducted using the entire Web of Science database in September 2022 and August 2023. Of the final 211 papers included in the review, models and their applications were categorized according to this review's research interests in seven distinct categories aggregating the papers' research themes and model outputs. Restoration site context was added by identifying 229 unique study site locations from the full database, which were catalogued and analysed against raster data for the Köppen–Geiger climate classification scheme. A majority of northern peatland sites were in temperate oceanic zones or humid continental zones that experienced snow. Over one in five models from the full database of papers were unnamed and likely intended for single use. Key themes emerging from topics covered by papers in the database included the following: modelling restoration development from a bog growth perspective, the prioritization of modelling greenhouse gas (GHG) emissions dynamics as a part of policymaking, the importance of spatial connectivity within or alongside process-based models to represent heterogeneous systems, and the increased prevalence of remote sensing and machine learning techniques to predict restoration progress with little physical site intervention. Models are presented according to their application to peatlands or broader ecosystem and organized from most to least complex. This review provides valuable context for the application of ecohydrological models in determining strategies for peatland restoration and evaluating post-intervention development over time. [ABSTRACT FROM AUTHOR]

Raised bogs (peat moss-dominated wetlands) are under environmental pressure but valued for their specific biodiversity and climate-mitigating potential. Strong efforts to restore these unique ecosystems contrast with a limited focus on cultural heritage management in bogs, putting their exceptional cultural heritage at risk. We take a new perspective on cultural heritage management in bog remnants and make recommendations for measures synergetic to their natural and cultural heritage. We focus on tangible cultural remains on the surface of bog remnants and surrounding former bog areas in the Netherlands, where bogs have long been under exceptional use and environmental pressure. To reach this objective, we first (1) explore the range and diversity of tangible cultural remains on the land surface through analysis of three case studies, (2) conduct a systematic inventory of how such cultural remains are currently incorporated in land management in and around 17 bog remnants, and (3) based on that develop a range of recommendations for improved integral management. We illustrate how preserving and displaying cultural remains can be aligned with the achievement of ecological goals in bog nature reserves. [ABSTRACT FROM AUTHOR]

This present article is an account of the sense of place in the poetry of Seamus Heaney and John Montague. Each poet is approached through poems representative of a rural imaginary of boglands, potato drills, and bodies of water. The line of argument is sensitive to the numinous meanings Heaney and Montague imbue their natural worlds with, and the analysis focuses upon their rootedness and reliance on place for poetic inspiration. In Heaney's account, this is demonstrated with a nuanced and deliberative approach to poems that excavate the historical layerings of the bog while also tying this back to agricultural labor. This yields the source of Heaney's craft of writing, just as Montague constructs a sort of ars poetica through images of water. This is a brief and comprehensive analysis of both poets and the importance of regionalism in late twentieth-century Irish or Northern Irish poetry. [ABSTRACT FROM AUTHOR]

The results of a study on the productivity of plant communities after a crown fire in a drained oligotrophic bog in the southern taiga of Western Siberia are presented. A quantitative assessment of biological productivity in areas with varying degrees of pyrogenic disturbance is given. The reserves of the grass-shrub and moss layers in the most disturbed area in the second year of restoration amounted to 1220 g/m2, production was 324 g/m2 per year; in the third year, reserves increased to 1635 g/m2 and production increased to 1038 g/m2 per year due to the growth of blueberries, while the production in the control site with high reserves of living phytomass (2200 g/m2) amounted to 745 g/m2 per year. There was a change in the structure of the phytomass, compaction of the deposit by 34%, and an increase in the mortmass of vascular plants by three times. The living mass of roots in the disturbed area concentrated in the upper layer of 0–10 cm, while it was distributed in the control area in the layer of 10–30 cm. It was found that the roots of dead pines retain the morphological characteristics of living ones during the first two years and pass into the fraction of dead roots on the third year of pyrogenic succession. Carbon losses during burning of the top layer of tow up to 20 cm amounted to 3016 g C/m2, 500 g/m2 of which can be buried as a layer of coal in peat. [ABSTRACT FROM AUTHOR]

Steve Lentini is founder and CEO of Positive Intelligence, an executive coaching service that helps CEOs and other C‐suite executives get the best out of their teams. In this article, he discusses how to navigate potential conflicts between boards of directors and executive management teams, who can often have opposing goals. [ABSTRACT FROM AUTHOR]

Ombrotrophic suboceanic bogs are distinguished by a high diversity of complex microlandscapes within the bog massif. Each complex microlandscape is a separate intrabog ecosystem with a specific set of parameters and relationships. This study aims to assess the specifics of the characteristics and parameters of the complex microlandscapes as part of an ombrotrophic suboceanic Sphagnum bog and as stages of bog morphogenesis, and to establish the internal relationships and their relationship with external environmental factors. A comprehensive multidisciplinary approach was used to assess the functioning of the complex microlandscapes. It was found that the relationship with the air temperature is closer than with the bog water table dynamics. It was shown that the morphometric parameters of perennial dwarf shrubs can serve as indicators of the stages of development of bogs. The processes of the self-regulation of complex microlandscapes are weakened with the age of the complex microlandscape, as evidenced by an increase in the amplitude of temperature fluctuations and the level of bog waters, as well as the key physicochemical parameters of the peat deposit. This leads to a gradual, slow reorientation of the physicochemical processes occurring in the deposit, from the deposition of organic matter to the decomposition of peat biomass. [ABSTRACT FROM AUTHOR]

The Sphagnum habitat is a "miniature forest" to the mites, of which the layers offer different microenvironmental conditions. We studied the vertical distribution of the Oribatida, Mesostigmata, and Prostigmata groups in four layers (0–5 cm, 5–10 cm, 10–15 cm, and 15–20 cm) of a forest bog on Neshalvøya, Norway, to improve the knowledge of the ecology of these mites. The sampled bog was grazed by farm animals; thus, another aim was to investigate the vertical distribution of the oribatid species, which are intermediate hosts of tapeworms. The selected study site is known for its valuable yet increasingly endangered nature, so our aim was also to contribute to the knowledge on its diversity. We collected Sphagnum samples in four replicates and extracted them in the laboratory in modified Berlese funnels. In total, 16.880 mites were studied, including 16.384 Oribatida, 466 Mesostigmata, and 30 Prostigmata. The total abundance of mites, the Oribatida and Mesostigmata groups, was the highest in the upper layer of Sphagnum and decreased with depth, while the abundance of the Prostigmata did not follow any pattern. Among the Oribatida, at deeper layers, significant declines in abundance were observed in adults, but not in juveniles. Most oribatid species, e.g., Nothrus pratensis, preferred the upper layer of Sphagnum, whereas some preferred deeper layers. For example, Suctobelbella acutidens and Carabodes femoralis preferred the 5–10 cm layer, Quadroppia maritalis the 10–15 cm layer, and Ceratozetes gracilis and Eulohmannia ribagai preferred the deepest layer of Sphagnum. Adults and juveniles of the same species showed a preference for the same layer. In total, 62 species of the Oribatida were recorded, including 11 species that are known to be intermediate hosts of tapeworms. Most of them occurred in the upper layer of Sphagnum. Over 20% of the species were found exclusively in deeper layers, so sampling these layers is important for a better evaluation of the mites' diversity. Studying the vertical distribution of the mites in bogs helps us to understand their ecology, including their role as intermediate hosts of tapeworms, as well as their diversity. [ABSTRACT FROM AUTHOR]

Many continental paleoclimate archives originate from wetland sedimentary sequences. While several studies have investigated biomarkers derived from peat-generating vegetation typical of temperate/boreal bogs (e.g., Sphagnum), only scant information is available on emergent plants predominant in temperate/subtropical coastal marshlands, peri-lacustrine and fen environments. Here, we address this gap, focusing on two wetlands in the Mediterranean (Nisí fen and Tenaghi Philippon, Greece). We examined the concentration, homologue distribution, and hydrogen stable isotopic composition (δ[sup 2]H) of leaf wax n-alkanes in 13 fen plant species, their surrounding soil, and surface water during the wet growing season (spring) and the declining water table period (summer). Our findings indicate that local graminoid species primarily contribute to the soil n-alkane signal, with a lesser influence from forbs, likely owing to differences in morphology and vegetation structure. The δ[sup 2]H values of surface and soil water align with local average annual precipitation δ[sup 2]H, reflecting winter-spring precipitation. Consistently, the average δ[sup 2]H of local surface, soil, and lower stem water showed negligible evaporative enrichment, confirming minimal [sup 2]H-fractionation during water uptake. We find that δ[sup 2]H values of source water for wax compound synthesis in local fen plants accurately mirror local annual precipitation. Furthermore, despite differences between leaves and lower stems in n-alkane production rates, their δ[sup 2]H values exhibit remarkable similarity, indicating a shared metabolic substrate, likely originating in leaves. Our net [sup 2]H-fractionation values (i.e., precipitation to leaf n-alkanes) align with those in Chinese highlands and other similar environments, suggesting consistency across diverse climatic zones. Notably, our data reveal a seasonal decrease in the carbon preference index (CPI) in plant samples, indicating wax lipid synthesis changes associated with increased aridity. Additionally, we introduce a new parity isotopic difference index (PID) based on the consistent δ[sup 2]H difference between odd and even n-alkane homologues. The PID demonstrates a strong anticorrelation with plant CPI, suggesting a potential avenue to trace long-term aridity shifts through δ[sup 2]H analysis of odd and even n-alkane homologues in sedimentary archives. While further development of the PID is necessary for broad application, these findings highlight the intricate interplay between plant physiology, environmental parameters, and sedimentary n-alkanes in unravelling past climatic conditions. [ABSTRACT FROM AUTHOR]

Integrating hydrogen (H 2) production systems within natural gas (NG) supply chains can support smoothening transition to cleaner energy resources by utilizing existing infrastructures. This work investigates the dynamic conversion of boil-off gas (BOG) using steam methane reforming (SMR) to produce H 2 within liquified natural gas (LNG) process. The study extends beyond technical considerations to encompass a socio-economic approach, exploring optimal H 2 allocation to different monetization techniques (e.g., ammonia and methanol) subject to final market price and demand data. Dynamic simulation showed an excellent ability to address the variations in BOG flow, change in LNG temperature and pressure drop within the LNG supply chain, highlighting the need for adaptive flowrate and process setpoints. The H 2 productivity and yield are dependent on steam flow rates, steam to carbon ration (S/C) and energy input to the system. Optimizing the reformer temperature is the best practice to enhanced the conversion of BOG to H 2. Allocating approximately 74% of the produced H 2 to CO 2 -free ammonia production, and the remainder to methanol via CO 2 hydrogenation, achieves an annual profitability of $1.36 billion. However, when considering variable demand and price data over ten years, the model proposes flexible annual H 2 allocation to both monetization routes, resulting in an average yearly profitability of $6.84 billion. These findings underscore the importance of integrating interactive simulation approaches to address exogenous and endogenous uncertainties, providing a robust strategy against risks. The comprehensive approach presented in this study contributes to the understanding and strategic planning of H 2 production within LNG supply chains, emphasizing adaptability and economic viability in the dynamic landscape of the energy transition. • Integrating hydrogen generation into LNG supply networks helps move to cleaner energy. • Economic/technical feasibility of SMR for H 2 production from BOG was presented. • Aspen HYSYS model was developed to ensure reliable, safe, and optimal H 2 production. • Implementing flexible H 2 allocation strategies in response to market conditions generates significant economic gains. • Annual allocation flexibility for economic performance increased profitability by 80% ($6.84B). [ABSTRACT FROM AUTHOR]

Encroachment of vascular plants (VP) in temperate raised bogs, as a consequence of altered hydrological conditions and nutrient input, is widely observed. Effects of such vegetation shift on water and carbon cycles are, however, largely unknown and identification of responsible plant physiological traits is challenging. Process-based modelling offers the opportunity of gaining insights into ecosystem functioning beyond observations, and to infer decisive trait shifts of plant functional groups. We adapted the Soil–Vegetation–Atmosphere Transfer model pyAPES to a temperate raised bog site by calibration against measured peat temperature, water table and surface CO2 fluxes. We identified the most important traits determining CO2 fluxes by conducting Morris sensitivity analysis (MSA) under changing conditions throughout the year and simulated VP encroachment. We further investigated transferability of results to other sites by extending MSA to parameter ranges derived from literature review. We found highly variable intra-annual plant traits importance determining ecosystem CO2 fluxes, but only a partial shift of importance of photosynthetic processes from moss to VP during encroachment. Ecosystem respiration was dominated by peat respiration. Overall, carboxylation rate, base respiration rate and temperature sensitivity (Q10) were most important for determining bog CO2 balance and parameter ranking was robust even under the extended MSA. [ABSTRACT FROM AUTHOR]

The change in the content and composition of polycyclic aromatic hydrocarbons (PAHs) was studied in organic horizons of soils of the boreal zone subjected to combustion under oxygen deficiency conditions. Organic soil horizons from the oligotrophic bog and two types of forest ecosystems (lichen pine and green moss spruce forest) were analyzed. It was found that combustion conditions, the composition of burned organic material, and its flammability influence significantly the content and composition of PAHs. Polyarenes are formed, for the most part, at 300°C. As compared to original samples, their content increases from 2.7 to 9.7 times. The maximum content of PAHs in the samples is reached at 300°C, whereas it falls by 5.8–33.0 times at 500°C. An abrupt decrease in the PAHs content is probably due to the decomposition to simpler substances. The experimentally obtained ratio of low-molecular weight to high-molecular weight polyarenes, which exceeds one, may indicate the pyrogenic origin of PAHs. [ABSTRACT FROM AUTHOR]

The high-resolution pollen record retrieved from dated sediments of the Khanka Depression has made it possible for the first time to reconstruct evolution of vegetation in the south of the Russian Far East that occurred during one of the coldest phase of MIS 2 – the Younger Dryas. The results of the spore-pollen analysis have shown that worsening of climate conditions between 18 200 and 15 500 cal yr BP that occurred after the first, slight warming during MIS 2, caused boreal flora plants, dominating in the south of Russian Far East, to spread again in the drier and colder climate comparable to the Gydan Stage of the Sartan Glaciation. Their distribution areas in the cold climate that differed significantly from the modern ones again started to shift to the south due to increasing cooling. The spruce and small-leaved forests, sparse larch and dwarf birch, alder and dwarf pine forests, and also sphagnum bogs dominated in the ecosystems of the region. [ABSTRACT FROM AUTHOR]

The Andean swamp rat Neotomys ebriosus is a sigmodontine rodent restricted to the Central Andes of South America. A distribution map of the species in Peru have been previously drawn based on few of the localities where the species has been captured and collected. I update the distribution of the species in Peru based on new records from three different areas surveyed by the author, specimens at Museum collections in the United States and France from VertNet webpage, localities from the collection at the Natural History Museum of Universidad Nacional Mayor de San Marcos, and localities from the collection at the Natural History Museum of the Universidad Nacional San Agustín. The northern limit of the species distribution is increased based on new localities with collected individuals. Habitat used by N. ebriosus is mainly high Andean bogs; most individuals caught adjacent to the borders of Andean bogs and along streams near the bogs. Collected individuals leave unclear subspecies division and identity. [ABSTRACT FROM AUTHOR]

Premise: Shared geographical patterns of population genetic variation among related species is a powerful means to identify the historical events that drive diversification. The Sphagnum capillifolium complex is a group of closely related peat mosses within the Sphagnum subgenus Acutifolia and contains several circumboreal species whose ranges encompass both glaciated and unglaciated regions across the northern hemisphere. In this paper, we (1) inferred the phylogeny of subg. Acutifolia and (2) investigated patterns of population structure and genetic diversity among five circumboreal species within the S. capillifolium complex. Methods: We generated RAD sequencing data from most species of the subg. Acutifolia and samples from across the distribution ranges of circumboreal species within the S. capillifolium complex. Results: We resolved at least 14 phylogenetic clusters within the S. capillifolium complex. Five circumboreal species show some common patterns: One population system comprises plants in eastern North America and Europe, and another comprises plants in the Pacific Northwest or around the Beringian and Arctic regions. Alaska appears to be a hotspot for genetic admixture, genetic diversity, and sometimes endemic subclades. Conclusions: Our results support the hypothesis that populations of five circumboreal species within the S. capillifolium complex survived in multiple refugia during the last glacial maximum. Long‐distance dispersal out of refugia, population bottlenecks, and possible adaptations to conditions unique to each refugium could have contributed to current geographic patterns. These results indicate the important role of historical events in shaping the complex population structure of plants with broad distribution ranges. [ABSTRACT FROM AUTHOR]

Premise: We assessed changes in traits associated with water economy across climatic gradients in the ecologically similar peat mosses Sphagnum cuspidatum and Sphagnum lindbergii. These species have parapatric distributions in Europe and have similar niches in bogs. Sphagnum species of bogs are closely related, with a large degree of microhabitat niche overlap between many species that can be functionally very similar. Despite this, ecologically similar species do have different distributional ranges along climatic gradients that partly overlap. These gradients may favor particular Sphagnum traits, especially in relation to water economy, which can be hypothesized to drive species divergence by character displacement. Methods: We investigated traits relevant for water economy of two parapatric bryophytes (Sphagnum cuspidatum and S. lindbergii) across the border of their distributional limits. We included both shoot traits and canopy traits, i.e., collective traits of the moss surface, quantified by photogrammetry. Results: The two species are ecologically similar and occur at similar positions along the hydrological gradient in bogs. The biggest differences between the species were expressed in the variations of their canopy surfaces, particularly surface roughness and in the responses of important traits such as capitulum mass to climate. We did not find support for character displacement, because traits were not more dissimilar in sympatric than in allopatric populations. Conclusions: Our results suggest that parapatry within Sphagnum can be understood from just a few climatic variables and that climatic factors are stronger drivers than competition behind trait variation within these species of Sphagnum. [ABSTRACT FROM AUTHOR]

Northern peatlands have been a persistent net sink of atmospheric carbon (C) due to the greater rates of gross primary production (GPP) compared to ecosystem respiration (ER). Global warming has raised concerns about the C sink strength of northern environments. In the vast peatlands of the Hudson Bay Lowlands (HBL) region of Canada, warming‐induced changes in sea ice dynamics over the Bay have altered its advective influence on the adjacent lowlands. Despite our knowledge of the short‐term C exchange in these peatlands, there remain uncertainties in the long‐term combined response of GPP and ER to climate change. In this study, the satellite‐data‐driven Vegetation Photosynthesis and Respiration Model was employed to investigate the response of peatland GPP, ER, and net ecosystem exchange to temperature and moisture changes. The results show contrasting net CO2 exchange at the two peatland sites over the last 20 years, with the fen acting as a net C source (+24 g C m−2) to the atmosphere and the bog serving as a net C sink (−130 g C m−2). There is ample evidence that a warmer and wetter climate enhanced GPP more than ER, while cooler temperatures weakened the peatland net C sink, regardless of the moisture conditions. Additionally, the advective influence of Hudson Bay on the lowlands produced markedly different C dynamics between offshore and onshore winds, with higher respiration rates (12%–26%) during offshore winds. We discuss the implications for peatland C balance under more frequent onshore winds in the region. Plain Language Summary: Peatlands in northern environments play a vital role in the climate system by storing large amounts of carbon and helping to mitigate climate change. Understanding how peatlands respond to climatic changes is essential for accurate climate projections and informing climate policy decisions. In the vast peatlands of the HBL region of Canada, global warming and changes in sea ice over the Bay have affected the surrounding lowlands. We used satellite data to study how temperature and moisture changes impact carbon exchange in these peatlands. Over the past 20 years, we found that one peatland site released carbon into the atmosphere while another absorbed carbon. Warmer and wetter conditions increased plants' carbon uptake more than carbon release by respiration. In contrast, cooler temperatures weakened the peatland's ability to store carbon, regardless of soil moisture levels. The Hudson Bay's influence on the lowlands led to different carbon dynamics depending on wind direction, with higher respiration rates during offshore (land) winds than winds blowing from the Bay. Our findings have implications for understanding carbon balance in peatlands under changing climate conditions, especially considering the potential for more frequent onshore winds in the region. Key Points: Fen and bog sites in the Hudson Bay Lowlands (HBL) showed contrasting net CO2 exchange over the last 20 yearsPeatland carbon exchange varies with climate anomalies, with warmer and wetter conditions increasing photosynthesis more than respirationHigher frequency of onshore winds may strengthen CO2 uptake in the HBL due to the advective influence of the adjacent Bay [ABSTRACT FROM AUTHOR]

Scholars have radically turned away from the notion of 'natural borders' dictated by nature and now broadly agree that all borders are 'artificial' human constructs. However, there is a need to revisit environmental determinism in its nuances. We analyse the relation between distinct natural features and historical border development, using the notion of affordances and the example of raised bogs in the medieval and modern-period eastern Low Countries. For humans, bog landscapes in these periods functioned as both barriers and passageways through the spatiotemporal variability of these opposite affordances. At the scale of local settlement territories, large bog landscapes had the coercive agency to function as borderlands separating adjacent communities. Such coercion was absent on the larger spatial scale of princedoms. The growing economic importance of peat was a crucial driver for border demarcation at both scales from the late Middle Ages. Diplomatic risk calculation and path dependency explain the spatial concurrence and long persistence respectively of bog boundaries between successive polities. [ABSTRACT FROM AUTHOR]

Myrsine cirrhosa Lorence & K.R.Wood (Primulaceae), a new single-island endemic shrub species from Kaua'i, Hawaiian Islands, is described and illustrated. Notes on its distribution, ecology and conservation status are included. The new species is known from an area with ca. 45 individuals, where it is restricted to the remote central windward region of Kaua'i in open bogs and along open windy ridges. Suggested IUCN Red List status is CR (Critically Endangered). It differs from its Kaua'i congeners by its longer petals and narrowly elliptic leaves with strongly undulate margins and tendril-like apex. Phylogenetic analysis using RADseq data supports the recognition of this new species. [ABSTRACT FROM AUTHOR]

Mercury (Hg) is a pollutant that bioaccumulates in the food web, leading to health issues in humans and other fauna. Although anthropogenic Hg deposition has decreased over the past 20 years, our watersheds continue to be sources of Hg to downstream communities. Wetlands, especially peatlands in the Boreal Region of the globe, play a vital role in the formation of bioaccumulative methylmercury (MeHg). Few studies have assessed how increases in temperatures such as those that have already occurred and those predicted will influence the hydrologic transport of Hg to downstream communities or the net fluxes of gaseous Hg. The results indicate that peatland pore water concentrations of MeHg are increasing with ecosystem warming, and to some degree with elevated carbon dioxide (eCO2) in the Spruce and Peatland Responses Under Changing Environments (SPRUCE) experiment at the Marcell Experimental Forest (MEF) in northern Minnesota, USA. Similar to SPRUCE, in the Biological Response to A Changing Environment (BRACE) experiment in Canada, mesocosm pore water MeHg concentrations increased with soil warming. However, long-term peatland watershed streamflow fluxes of MeHg at the MEF indicate that the competing effects of climate warming and decreased atmospheric deposition have led to overall decreases in watershed MeHg transport. Mesocosm studies in the PEATCOSM experiment in Upper Michigan, USA, indicate that simulated fluctuating water tables led to higher concentrations of MeHg in peatland pore water that is available for downstream transport when water tables rise and the next runoff event occurs. Results from a winter peatland soil freeze/thaw simulation from large mesocosm cores from Jennie's Bog at the MEF indicate higher total Hg (THg) upon soil thawing but lower MeHg, likely a result of cold temperatures limiting methylation during thawing. Although there are lower MeHg concentrations after thawing, more THg is available for methylation once soils warm. Results from PEATCOSM and the literature also suggest that plant community changes that result in higher densities of sedges also lead to elevated MeHg in pore water. From a climate warming perspective, it appears that two complementary mechanisms, both related to decomposition, are at play that lead to increased pore water MeHg concentrations with warming. First, warming increases decomposition rates, leading to a higher availability of many ions, including Hg (and sulfur) species. Higher decomposition rates also lead to increases in soluble carbon which complexes with Hg species and assists in downstream hydrologic transport. However, if streamflow is decreasing with climate change as a result of landscape-level changes in evapotranspiration as suggested at MEF, the combination of less direct watershed Hg deposition and lower streamflow results in decreases in the watershed transport of MeHg. Given changes already occurring in extreme events and the rewetting and restoration of hydrology during peatland restoration, it is likely that methylation and pore water MeHg concentrations will increase. However, the landscape-level hydrologic cycle will be key to understanding the connection to downstream aquatic communities. Finally, gaseous Hg fluxes increase with warming and lead to decreases in peatland pools of Hg that may influence future availability for downstream transport. [ABSTRACT FROM AUTHOR]

How the resource use by consumers vary in different environments and time scales is one of the fundamental ecological questions. Replicated field studies are rare, however; so the extent to which nutrient use varies and why is uncertain. We studied an endangered tyrphobiotic species, the black bog ant (Formica picea), and its feeding preferences in temperate peatlands. We conducted a baiting experiment at three different sites with high nest densities, repeated over three years and three periods of growing season. Preferences for three main macronutrients (carbohydrates, proteins and lipids) were assessed. We hypothesised that if nutrient limitation plays a role, ants will have an increased need for proteins and lipids in early seasons when brood is raised, while carbohydrates use will increase in late seasons. We also expected that site identity would influence nutrient preferences, but not year. Our results supported the nutrient limitation hypothesis for proteins that were consumed more in the early season. In contrast, preference for carbohydrates was rather high and did not increase consistently through season. Although the occupancy of lipid baits was low overall, it increased at colder temperatures, in contrast to carbohydrate and protein baits. Nutrient preferences varied more among sites than years, with the lowest nutrient use observed in a diverse fen-meadow, consistent with the nutrient limitation hypothesis. Year affected ant abundance, but not bait occupancy. Our results suggest that black bog ants flexibly adapt their diet to environmental conditions and that an interplay between nutrient limitation and climate determines their feeding behaviour. [ABSTRACT FROM AUTHOR]

The use of species as a concept is an important metric for assessing biological diversity and ecosystem function. However, delimiting species based on morphological characters can be difficult, especially in aquatic plants that exhibit high levels of variation and overlap. The Sphagnum cuspidatum complex, which includes plants that dominate peatland hollows, provides an example of challenges in species delimitation. Microscopic characters that have been used to define taxa and the possibility that these characters may simply be phenoplastic responses to variation in water availability make species delimitation in this group especially difficult. In particular, the use of leaf shape and serration, which have been used to separate species in the complex, have resulted in divergent taxonomic treatments. Using a combination of high-resolution population genomic data (RADseq) and a robust morphological assessment of plants representing the focal species, we provide evidence to evaluate putative species in this complex. Our data support the recognition of S. cuspidatum , S. fitzgeraldii , S. mississippiense , and S. trinitense as genetically distinct species that can be separated morphologically. These results indicate that S. viride does not differ genetically from S. cuspidatum. Our results are broadly relevant to other aquatic groups where leaf shape and marginal teeth are used to distinguish species. [ABSTRACT FROM AUTHOR]

The response of soil respiration (Rsoil) to drought was studied for six typical oligotrophic mire biotopes in the middle taiga of Western Siberia: hollows with a dominance of Eriophorum vaginatum (hollow E) and Scheuchzeria palustris (hollow Sh), sphagnum bog with sparse low pine trees (open bog), and forested oligotrophic bogs (ryams) covered with dwarf shrub–pine–sphagnum vegetation (tall ryam and ryam). For this purpose, a regression model linking Rsoil with the level of bog water was constructed. Cumulative soil respiration (Rsoil(cum)) was measured in June–August 2021 and 2022. In the dry summer of 2022, Rsoil(cum) values increased from waterlogged (hollow E) to better drained (tall ryam and ryam) biotopes and comprised 135 ± 2.3, 139 ± 2.4, 275 ± 7.8, 279 ± 7.5, 466 ± 16.4, 510 ± 18.5 g C/(m2 season) for the considered sequence, respectively (mean ± standard deviation). An extremely low precipitation in July 2022 (6 mm) led to a sharp decrease in the water table level in August and an increase in the thickness of aerated zone with a corresponding increase in soil respiration. The Rsoil(cum) values in summer 2022 were 29 to 54% higher than those in the same period in 2021. The most active growth of Rsoil with a decrease in the water table level was observed at the periphery of the mire massif (tall ryam, ryam, and open bog biotopes) in contrast to its central parts. [ABSTRACT FROM AUTHOR]

Northern fens, that host unique biota and form a remarkable carbon stock, are sensitive to changes in the moisture balance and, therefore, may be strongly affected by climatic fluctuations. However, long‐term monitoring and palaeoecological studies of fens are relatively rare and, as a result, their responses to past and current climatic fluctuations are poorly known. In this study, we examined the recent vegetation change as well as changes in testate amoeba communities in the mire margin of a subarctic fen in Finnish Lapland with four peat profiles. Testate amoebae were used as indicators of past fluctuations in water table depth. The vegetation showed a drastic shift from sedge‐dominated fen to Sphagnum‐dominated communities during the late 20th and the early 21st centuries. This shift was accompanied by a turnover in the testate amoeba community. Testate amoeba‐based water table reconstructions indicated recent drying. This may be due to the lowering of the water table either from accelerated Sphagnum increment or enhanced evaporation. The observed hummock establishment concurs with the documented hemisphere‐wide expansion trend of hummock communities in fens. This change may strengthen the carbon sink and storage capacity of these peatlands, which could be viewed as a welcome negative feedback process to the ongoing climate warming. However, the change also poses a threat to biodiversity since fens are not only species‐rich habitats but are also endangered ecosystems. [ABSTRACT FROM AUTHOR]