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Stable and high water levels are crucial for wetland ecosystems, impacting their state, vegetation and conservation. To make informed conservation decisions, it is essential to consider the full range of ecosystem‐level threats associated with artificially lowered water levels. This becomes particularly challenging when dealing with diffuse and indirect impacts, such as ombrotrophic bogs near underground mining activities that extract groundwater. In this study, we monitored water tables using automatic pressure loggers over an 11‐year period in a protected hemiboreal bog and in drained peatland surrounding it in northeastern Estonia. The bog is located within the groundwater cone of depression caused by an adjacent oil‐shale mine, approximately 60–70 m deep. By comparing monitoring points along the bog‐drained forest gradient and analysing time series data, we were able to distinguish the influences of climate and mining activities on water levels in the bog. Our findings indicate that mining activities have clear effects on deeper bedrock aquifers and the bog itself, exacerbating the impacts of recent drought events. The dynamics of the hydraulic heads at different monitoring points reveal local infiltration 'windows' within the bog, likely resulting from underlying fracture zones in the bedrock. Considering the escalating intensity of climate change, mires' vulnerability to these combined impacts is expected to increase. Therefore, adopting a precautionary and forward‐thinking conservation strategy is crucial when addressing ongoing or future drainage and mining activities near protected wetlands. [ABSTRACT FROM AUTHOR]

The dynamics of water and solutes were investigated in two northern bog ponds using sensor networks and discrete water samples. Embedded sensors monitored water level (S), precipitation (P), evaporation (E), water temperature (T) and specific conductivity (SC) in the peatlands and encircled ponds at 30 min time intervals from 2009 to 2015. Pond water chemistry was monitored seasonally from 2000 to 2020. Daily hydrographs and water budgets indicated that both bogs are ombrotrophic systems, perched above the local water table. Although the predominant flowpath for liquid water was precipitation → pond → peatland → underlying glacial deposits, evaporation accounted for 70% to 90% of water losses. High dissolved organic matter (DOM) in the ponds resulted from transient reversals of flowpath and from molecular diffusion across the peatland/pond interface (a tea bag effect). DOM of peatland origin dominated pond water chemistry, regulating the concentration of important metals, major nutrients and the acid–base status of both bog ponds. Elevated concentrations of Fe, Hg and MeHg in the ponds reflected ligand binding by DOM. The formation of DOM‐Fe‐PO4 complexes likely accounted for >3‐fold higher P concentration relative to nearby clearwater lakes. Linear regression of dissolved organic carbon (DOC) against the anion deficit indicated that DOM contributed up to 6.6 mEq of strong acid per gramme carbon in pond waters. Winter maxima in the seasonal cycles of DOC, Ca, Mg, N, P, Hg and MeHg in both bog ponds were attributable, in large part, to salting out during ice formation. We conclude that multiple methods are needed to understand the dynamics of water and solutes in bog ecosystems. [ABSTRACT FROM AUTHOR]

Long‐term carbon and nitrogen dynamics in peatlands are affected by both vegetation production and decomposition processes. Here, we examined the carbon accumulation rate (CAR), nitrogen accumulation rate (NAR) and δ13C, δ15N of plant residuals in a peat core dated back to ~8500 cal year BP in a temperate peatland in Northeast China. Impacted by the tephra during 1160 and 789 cal year BP and climate change, the peatland changed from a fen dominated by vascular plants to a bog dominated by Sphagnum mosses. We used the Clymo model to quantify peat addition rate and decay constant for acrotelm and catotelm layers during both bog and fen phases. Our studied peatland was dominated by Sphagnum fuscum during the bog phase (789 to −59 cal year BP) and lower accumulation rates in the acrotelm layer was found during this phase, suggesting the dominant role of volcanic eruption in the CAR of the peat core. Both mean CAR and NAR were higher during the bog phase than during the fen phase in our study, consistent with the results of the only one similar study in the literature. Because the input rate of organic matter was considered to be lower during the bog phase, the decomposition process must have been much lower during the bog phase than during the fen phase and potentially controlled CAR and NAR. During the fen phase, CAR was also lower under higher temperature and summer insolation, conditions beneficial for decomposition. δ15N of Sphagnum hinted that nitrogen fixation had a positive effect on nitrogen accumulation, particular in recent decades. Our study suggested that decomposition is more important for carbon and nitrogen sequestration than production in peatlands in most conditions and if future climate changes or human disturbance increase decomposition rate, carbon sequestration in peatlands will be jeopardized. [ABSTRACT FROM AUTHOR]

Peatlands store approximately one-half of terrestrial soil carbon and one-tenth of non-glacial freshwater. Some of these important ecosystems are located near heavy metal emitting smelters. To improve the understanding of smelter impacts and potential recovery after initial pollution controls in the 1970s (roughly 50 years of potential recovery), we sampled peatlands along a distance gradient of 134 km from a smelter in Sudbury, Ontario, Canada, an area with over a century of nickel (Ni) and copper (Cu) mining activity. This work is aimed at evaluating potential shifts in bacterial and archaeal community structures in Sphagnum moss and its underlying peat within smelter-impacted poor fens. In peat, total Ni and Cu concentrations were higher (0.062–0.067 and 0.110–0.208 mg/g, respectively) at sites close to the smelter and exponentially dropped with distance from the smelter. This exponential decrease in Ni concentrations was also observed in Sphagnum. 16S rDNA amplicon sequencing showed that peat and Sphagnum moss host distinct microbiomes with peat accommodating a more diverse community structure. The microbiomes of Sphagnum were dominated by Proteobacteria (62.5%), followed by Acidobacteria (11.9%), with no observable trends with distance from the smelter. Dominance of Acidobacteria (32.4%) and Proteobacteria (29.6%) in peat was reported across all sites. No drift in taxonomy was seen across the distance gradient or from the reference sites, suggesting a potential microbiome recovery toward that of the reference peatlands microbiomes after decades of pollution controls. These results advance the understanding of peat and Sphagnum moss microbiomes, as well as depict the sensitivities and the resilience of peatland ecosystems. [ABSTRACT FROM AUTHOR]

Peat soils of the taiga zone of Western Siberia are historically relatively poorly studied. In the diagnostics of peat soils, the question of the belonging of the sphagnum litter horizon to the soil profile, as well as the identification of its lower boundary, remains unresolved. In the WRB system, as well as in the Russian soil classification system, sphagnum litter is considered as a vegetation cover, while in the Soviet classification it is considered an integral part of the soil profile. The latter point of view is shared by the majority of Russian researchers. Using the materials obtained in the study of peat soils in the basin of the Kazym River (right tributary of the Ob River, northern taiga subzone, Western Siberia), a comparative characteristic of the sphagnum litter horizon (0–20 cm) and the underlying peat horizon (20–50 cm) was carried out with respect to three parameters: the botanical composition of peat, the degree of peat decomposition, and the color of peat soil. All soils are differentiated into the litter horizon and the peat horizon by at least one parameter (5% of the profiles) but, in 71% of cases, by all the three parameters at once. The degree of profile differentiation into the moss litter and proper peat horizons tends to increase in the soil sequence from oligotrophic pine–shrub–sphagnum bogs to oligotrophic complex ridge–hollow bogs and to mesotrophic bogs. In the overwhelming majority of oligotrophic peat soils, the transition from the litter horizon to the peat horizon is gradual, which does not allow a reproducible assessment of the position of the boundary of litter layer in the soil profile. It is proposed to set a fixed lower boundary of sphagnum litter as a depth of 20 cm from the bog surface and to consider sphagnum litter as the surface horizon of peat soils. [ABSTRACT FROM AUTHOR]

Farmland soil pollution is a serious problem worldwide threatening environment and human health. Microbial communities plays a key role in soil function. The purpose of this study was to analyze the relationship between microbial structure and soil physicochemical properties under different heavy metal pollution levels, find out heavy metal tolerant species under different environmental conditions, then provide useful reference for the bioremediation of contaminated farmland. In this study, 16s rRNA high-throughput sequencing technology was used, multiple comparisons and correlation analyses of the data were performed using R software. The results showed that study area A was contaminated by heavy metal Cd, and study area A, B and C were contaminated by heavy metal Hg. From the analysis of the community structure of the samples, it can be seen that the dominant bacterial phyla were Proteobacteria, Acidobacteriota, Chloroflexi, Actinobacteria, and 10 others. Correlation and RDA analysis of samples showed that the heavy metals Hg and As in peat were related to dominant bacteria phyla, and the physicochemical properties of soil potential of hydrogen (pH), total nitrogen (TN), available nitrogen (AN), available phosphorus (AP), available potassium (AK), and soil organic matter (SOM) were significantly positively correlated with the bacteria (Acidobacterta and Chloroflexi). Moreover, Chloroflexi was more tolerant to the heavy metals Hg and As. There was a significant correlation between bacterial community abundance and diversity in the four study areas. Soil heavy metal concentration and soil physicochemical properties affected the main phyla, bacterial community abundance and bacterial diversity of peat soil. These results indicate that some microorganisms have strong tolerance to heavy metal pollution and certain heavy metal digestion ability, which can create a good environment for farmland soil remediation. This manuscript is the first study on a new crop—Sphagnum in China. It mainly discusses the reaction of soil bacteria and microorganisms of Sphagnum in farmland to heavy metals and soil physical-chemical properties. [ABSTRACT FROM AUTHOR]

The paper describes a dataset, comprising 236 surface moss samples and 143 testate amoeba taxa. The samples were collected in 11 Sphagnum-dominated bogs during frost-free seasons of 2004, 2007, 2009, 2017, and 2022. For the whole dataset, the sampling effort was sufficient in terms of observed species richness (143 species in total), though a regional species pool is deemed to be discovered incompletely (143 species is its lower 95 % confidence limit using Chao's estimator). The local community composition demonstrated high heterogeneity in a reduced ordination space. It supports the opinion that the high versatility of bog ecosystems should be taken into account during ecological studies. Dataset:  https://doi.org/10.15468/mnapsy. Dataset License: CC-BY 4.0 [ABSTRACT FROM AUTHOR]

In the liquefied natural gas (LNG) terminal, during the compression process of boil-off gas (BOG), dropping liquid or heavy components condense on the filter screen of the BOG low-pressure compressor inlet, resulting in increased pressure differential and even compressor tripping. The poor load matching between the low-pressure and high-pressure compressors in series operation can easily lead to frequent compressor trips. To address the above issues, taking a certain LNG terminal as an example, a method combining theoretical and simulated calculations with field operation experience was employed to optimize the design of the low-pressure compressor suction knock-out drum and the series operation process of the low-pressure and high-pressure compressors from the process design aspect. The process optimization of the suction knock-out drum design improve the separation efficiency of liquid droplets or heavy components carried in the BOG, avoiding high-pressure differential alarms or compressor tripping caused by the accumulation of liquid droplets or heavy components on the filter element. The addition of a BOG buffer drum between the series-connected low-pressure and high-pressure compressors, with a certain buffering time, effectively balances gas load fluctuations, reduces the difficulty of operating the two compressors in series, and decreases frequent tripping caused by load mismatch. After optimization, the BOG treatment system of this LNG terminal has been running smoothly for a long time. [ABSTRACT FROM AUTHOR]

Electron transfer to peat particulate organic matter (POM) as terminal electron acceptor (TEA) in anaerobic respiration has been hypothesized to lower methane emissions from peatlands by competitively suppressing methanogenesis and/or allowing for anaerobic oxidation of methane. We herein provide evidence for two critical aspects of this hypothesis: (a) peat POM is present in a reduced state in situ in the anoxic peat subsurface, and (b) reduced POM at the oxic‐anoxic interface in peat soils can be oxidized by dissolved oxygen (DO), restoring its TEA capacity. We reacted reduced POM from three ombrotrophic bogs in Sweden with DO in soil‐packed column‐breakthrough experiments (CBEs), mimicking oxidation reactions at the oxic‐anoxic interface. Breakthrough of DO was substantially retarded relative to the inert tracer bromide, consistent with DO reduction by POM. Control experiments confirmed abiotic DO reduction and excluded DO consumption through aerobic respiration. Modeling DO breakthrough revealed fast and slowly reacting POM moieties with reaction times spanning minutes to days. Complementary push‐pull tests (PPTs) in the anoxic subsurface of one bog confirmed results from laboratory CBEs: lower recoveries of injected DO compared with bromide supported DO reduction by reduced POM. Rates of reduction of injected DO decreased with increasing number of injections, consistent with continuous oxidation of reduced POM. Electron‐donating capacities of POM to DO in CBEs and PPTs were comparable at 40–130 μmol e−/g dry POM. Our results substantiate that POM is a regenerable TEA at oxic‐anoxic interfaces in peat soils and, thereby, may substantially lower CH4 emissions from peatlands. Plain Language Summary: Northern peatland soils contain large amounts of carbon stored as peat particulate organic matter (POM). Understanding how microorganisms turn over this carbon is important because turnover can release not only carbon dioxide but also methane, a more potent warming gas. Recent literature proposes that microorganisms in oxygen‐free parts of peat soils can turn over carbon substrate molecules by oxidation to carbon dioxide coupled to transferring electrons liberated in this process to POM. This newly proposed pathway is expected to substantially lower methane formation and emissions but relies on POM's ability to accept electrons. However, continuous electron transfer to POM in oxygen‐free soil parts would eventually consume the capacity of POM to accept electrons, at which point methane formation would set in. In our work, we show that the electrons stored in POM under anoxic conditions can be transferred to dissolved oxygen (DO) which periodically enters the peat soils by various means. Reaction with DO thus restores POM's capacity to accept electrons in subsequent oxygen‐free periods and thus its potential to suppress methane emissions. Our findings will help to better understand the role of POM in peatland carbon turnover to carbon dioxide and methane. Key Points: Peat particulate organic matter (POM) in the anoxic subsurface of three Swedish ombrotrophic bogs is present in reduced statesPeat POM transfers 40–130 μmol e− per g to dissolved oxygen with reaction times spanning from minutes to daysPOM acts as regenerable terminal electron acceptor in anaerobic respiration at oxic‐anoxic interfaces in peat soils [ABSTRACT FROM AUTHOR]

Tracked vehicles are widely deployed for heavy lifting and transportation on inaccessible terrains such as swamps, bogs, and peatlands. The stability of a tracked vehicle is traditionally assessed only under uniaxial loading conditions and the impact of combined loading from different directions is ignored. This makes the conventional design framework somewhat unreliable. The failure envelope approach has been widely employed to assess the load-carrying capacity of shallow foundations. However, the failure envelopes available in public domain mainly focused on single isolated foundations, ignoring the interference effect between the tracks due to the rigid connection of the vehicle. This paper aims to develop an integrated framework to assess the stability of a tracked vehicle on a soft soil under fully three-dimensional loading conditions. The finite element method is adopted to simulate the soil–vehicle interactions, with the tracks idealised as two shallow foundations in parallel. The stability of the foundation system is described in terms of failure envelopes considering various track configurations and load combinations. Failure envelopes are represented by expressions and ultimately integrated into a multiple-nested function to determine the overall stability factor. The framework is demonstrated by a case study of designing a tracked vehicle under combined loading conditions. [ABSTRACT FROM AUTHOR]

The paper presents new data and reviews previously obtained results on the late glacial to Holocene history of peatlands in the southern part of the Baikal region under conditions of regional climate changes. To better understand climate signals, we have combined vegetation and geochemical variation data in 4.6 m thick peat deposits in the Vydrino bog located on the Tankhoi piedmont plain south of Lake Baikal. The territory has been swamped since 13.1 cal ka BP when the peatland started developing as a fen upon a sedimentary substrate. The 13.1–9.5 cal kyr climate record included two events of warming separated by an excursion of dry cold climate. Warming continued till 9.0 cal ka BP and eutrophic peat formation occurred in favorable temperature and moisture conditions. Another warming episode between 9.0 and 8.4 cal ka BP ended up with the Holocene climate optimum while the bog became mesotrophic. About 7.3–6.5 cal ka BP, the temperature and moisture inputs were no longer optimal for fir and spruce forests in the Vydrino area, which led to dramatic changes in landscape and vegetation. The wet and warm climate gradually became drier and colder from 6.5 to 2.3 cal ka BP, with a brief warm excursion about 5.5–5.3 cal ka BP. The peat deposition was interrupted in a cold climate from ∼2.3 cal ka BP to ∼0.7 cal ka BP, and the bog became oligotrophic afterwards. The newly obtained data allowed us to compare the paleoclimatic indicators available for the south Baikal region to determine their compatibility and inconsistency. In addition, we provide a general view to the quality of the climate and environmental reconstructions in the Baikal region by comparison of the data on its peatland study. [ABSTRACT FROM AUTHOR]

Hereby, we report the new experimental data of plant biomass and biological productivity (net primary production, NPP) of wetland/peatland plant communities of oligotrophic bogs located on the same latitude, but at a distance of 1300 km west-east in the forest–steppe region of Western Siberia. The data were collected by implementing direct in situ measurements based on a unique methodology developed by authors. The study revealed that the values of net primary production (NPP) are basically constrained by the live fraction of plant biomass (or phytomass). It also revealed that the dead fraction of plant biomass (mortmass), along with the live fraction of biomass (phytomass) and net primary production (NPP), all major components of the carbon cycle, differ significantly at the two study sites. The values of dead biomass (mortmass), live biomass (phytomass) and net primary production (NPP) were found at significantly higher values in bog ecosystems studied in western regions than in those of the eastern regions. [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 timespans on 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- 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 categorise current process-based modelling uses in peatlands in order to investigate the applicability and appropriateness of eco- and/or hydrological models for northern peatland restoration. Two literature searches were conducted using the Web of Science entire database in September 2022 and August 2023. Of the final 211 papers included in the review, models and their applications were categorised according to this review's research interests in 7 distinct categories aggregating the papers' research themes and model outputs. Restoration site context was added by identifying 234 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 experiencing snow. Over one in five models from the full database of papers was unnamed and likely single-use. The top three most-used of these models, based on the frequency of their use on distinct site locations, were LPJ, ecosys, and DigiBog, in that order. Key themes emerging from topics covered by papers in the database included: modelling restoration development from a bog growth perspective; the prioritisation of modelling 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 emerging prevalence of remote sensing and machine learning techniques to predict restoration progress with little physical site intervention. 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]

Land use changes in temperate peat soils significantly impact topsoil organic carbon (SOC) content and soil pH, with implications for ecosystem functioning and carbon storage. Therefore, assessing soil organic carbon (SOC) and pH is instructive for reducing global carbon emissions. In this study, peat soil samples were collected from 0-10 cm and 10-20 cm depths in Co-Offaly, Ireland, to examine the SOC and soil pH across various peatland use types, including grassland (improved and unimproved), forestry, industrial cutaway, and cutover bog. The results indicate that among the peatland use types, intensive grassland exhibited the lowest SOC content, likely due to intensive management practices such as grazing, fertilizer application, and ploughing. Additionally, the land use change significantly impacts the soil pH, with a trend in soil pH across the different land use types observed as improved grassland > unimproved grassland > industrial cutaway > forestry > cutover. A strong negative correlation was observed between SOC content and soil pH, indicating that increased soil pH levels are associated with decreased SOC in temperate peatlands. This research contributes valuable insights into the intricate interplay between land use, SOC, and soil pH, offering pertinent knowledge for strategies aimed at enhancing global carbon management efforts. [ABSTRACT FROM AUTHOR]

Climate warming and projected increase in summer droughts puts northern peatlands under pressure by subjecting them to a combination of gradual drying and extreme weather events. The combined effect of those on peatland functions is poorly known. Here, we studied the impact of long‐term water level drawdown (WLD) and contrasting weather conditions on leaf phenology and biomass production of ground level vegetation in boreal peatlands. Data were collected during two contrasting growing seasons from a WLD experiment including a rich and a poor fen and an ombrotrophic bog. Results showed that WLD had a strong effect on both leaf area development and biomass production, and these responses differed between peatland types. In the poor fen and the bog, WLD increased plant growth, while in the rich fen, WLD reduced the growth of ground level vegetation. Plant groups differed in their response, as WLD reduced the growth of graminoids, while shrubs and tree seedlings benefited from it. In addition, the vegetation adjusted to the lower WTs, was more responsive to short‐term climatic variations. The warmer summer resulted in a greater maximum and earlier peaking of leaf area index, and greater biomass production by vascular plants and Sphagnum mosses at WLD sites. In particular, graminoids benefitted from the warmer conditions. The change towards greater production in the WLD sites in general and during the warmer weather in particular, was related to the observed transition in plant functional type composition towards arboreal vegetation. [ABSTRACT FROM AUTHOR]

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Seismic lines are the dominant anthropogenic disturbance in the boreal forest of the Canadian province of Alberta, fragmenting over 1900 km2 of peatland areas and accounting for more than 80% of all anthropogenic disturbance in this region. The goal of this study is to determine whether the wildland fires that burn across seismic lines in peatlands result in the regeneration of woody vegetation within the ecotonal areas adjacent to seismic lines. We use a combination of seismic line and vegetation structural characteristics derived from multi-spectral airborne lidar across a post-fire peatland chronosequence. We found an increasing encroachment of shrubs and trees into seismic lines after many years since a fire, especially in fens, relative to unburned peatlands. Fens typically had shorter woody vegetation regeneration (average = 3.3 m ± 0.9 m, standard deviation) adjacent to seismic lines compared to bogs (average = 3.8 m ± 1.0 m, standard deviation), despite enhanced shrubification closer to seismic lines. The incoming solar radiation and seismic line age since the establishment of seismic line(s) were the factors most strongly correlated with enhanced shrubification, suggesting that the increased light and time since a disturbance are driving these vegetation changes. Shrub encroachment closer to seismic lines tends to occur within fens, indicating that these may be more sensitive to drying conditions and vegetation regeneration after several years post-fire/post-seismic line disturbance. [ABSTRACT FROM AUTHOR]

Fires in forested raised bogs occur both as a result of natural processes and as a result of human activity. Although there is a generally accepted opinion that their impact on ecosystems is significant, there is still a lack of scientifically reliable research on how individual components of damaged ecosystems change and recover under the influence of fires. The purpose of our study was to assess whether and how these fires affect the chemical composition of the peat layers. This study is based on a geochemical analysis of surface peat layers in areas after a controlled fire and in adjacent areas which were untouched by the fire in a raised bog of Čepkeliai. This study showed a low concentration of potentially toxic elements in the peat layers. In this respect, it is clear that there is no risk of environmental contamination in this natural raised bog. Furthermore, the research revealed other important insights on the combination of potentially toxic elements that can be used as a tracer for the identification of fire events that occurred in the past. Multiple analyses on various combinations of potentially toxic elements revealed the optimal combination (Cu-Zr-Pb-Se-Fe) for distinguishing between the burnt and non-burnt areas. Based on the results of our research, it can be stated that the low-temperature, controlled burning of the peat layers of raised bog forests can be successfully carried out to achieve the environmental and ecological goals of forest management. [ABSTRACT FROM AUTHOR]

The permafrost properties and cryostructure of Holocene peatlands and underlying the Pre-Holocene deposits within Pur-Taz interfluve in the Northern West Siberia were studied. The cryolithological description, particle size, botanical compositions based on plant macro-fossils, and radiocarbon age from 8500 ± 240 cal BC to 1810 ± 150 cal AD were defined. The polygonal peatlands were formed in lacustrine-bog basins. The "arboreal" horizon at the bottom of the peat, which is characteristic of Northern West Siberia, was identified. This "arboreal" horizon dates to the Boreal and Atlantic periods of the Holocene – 8500 ± 240 cal BC and 7390 ± 210 cal BC, which explains the occurrence of forest tundra in the area of typical modern tundra during the Holocene Climatic Optimum. The vegetation composition of peat-forming plants, the ash content, and the decomposition degree of organic matter were controlled by changing natural conditions and dynamics of peat accumulation during the Holocene: flooding and burial of woody vegetation, overgrowing and eutrophication of water bodies, the gradual accumulation of peat and syngenetic ice-wedge polygon formation, peat accumulation slowing caused by drainage of drained lake basin surface. Organic frost boils on the peatland surface indicate modern deepening of the permafrost Table and are related to an increase of the microorganism activity in the thawed, poorly decomposed peat. The peat accumulation rate was about 1 mm per year. A 2-m peat layer containing ground ice has accumulated over 2500 years. The purpose of the present work is study of the history of the vegetation on the northern limits of treeline. Examination of the peat, macrofossil, decomposition degree, and ash content history of a peat sections on the Pur-Taz Interfluve in North-Western Siberia, provides a long-term view of vegetation dynamics, peatland change, and climate history during the Holocene at the Arctic treeline. [Display omitted] [ABSTRACT FROM AUTHOR]

Dating young peatlands using the 210Pb dating procedure is a challenging task. The traditional 210Pb age models assume an exponential decline in radioactivity in line with depth in the peat profile. Lead exhibits considerable migratory capacity in Arctic peatlands; hence, to perform precise peat dating, existing models should be enhanced to remove the effects of migration. Independent isotope chronometers, such as 137Cs, can verify this. The Monte Carlo method and IP-CRS were utilised, together with several CA, CF/CS, PF, and CF models, to analyse the peat core samples acquired in the Arkhangelsk region. Data analysis revealed that the height partitioning of 137Cs and 210Pb is associated with physical characteristics, like the peat ash and the bulk density of the bog. Comparison between the natural activity of 210Pb in the peat and the radioactivity of 137Cs measured at depths of 19–21 cm in relation to the global fallout in 1963 indicated that the CF/CS, CF, and IP-CRS models (1965, 1962 and 1964, respectively) gave the closest age to the reference point given. IP-CRS was found to be the preferred model of these three options, as it gave a rather closer correlation with the 137Cs activity specific to the reference layer, allowing the error. The core dating of 210Pb showed an age of 1963 for a depth of 17–19 cm, which was in agreement with the reference horizon 137Cs and ash content, thus validating the accuracy and sufficiency of the selected model turf profile chronology. The maximum content of man-made radioisotopes in the peatlands corresponded to the formulation of the Partial Test Ban Treaty of 1963. The rates of accumulation of peat and atmospheric flux of 210Pb are in good agreement with the values available for the bogs of Northern Europe and those previously estimated by the authors in the subarctic region of European Russia. Although the problems of the complex migration-related distribution of 210Pb in the peat layer were considered, the dating methods used were effective in our study and can be adapted in following studies to perform the age determination of different peat deposits. [ABSTRACT FROM AUTHOR]

We present a reliable and robust open dynamic chamber for measuring greenhouse gas exchange in peatlands with minimal disturbance of the ground. This chamber, called the "skirt chamber", is based on a transparent plastic film placed above an open frame made of sparse interwoven wires and expanded around the base of the chamber below a steel chain that ensures contact to the ground, avoiding damage, trenching, and cutting vegetation. Gas exchange is determined using a portable gas analyzer from a mass balance in which the imperfect sealing of the chamber to the ground is quantified through the injection of a methane pulse. The method was tested on a pristine peatland dominated by Sphagnum magellanicum located on Navarino Island in the subantarctic Magellanic ecoregion in Chile. Our results indicate that the skirt chamber allowed the determination of methane fluxes and ecosystem respiration in about 20 min, with a limit of detection of 0.185 mg CH 4 m -2 h -1 and 173 mg CO 2 m -2 h -1 , respectively. We conclude that the skirt chamber is a minimally intrusive, fast, portable, and inexpensive method that allows the quantification of greenhouse gas emissions with high spatial resolution in remote locations and without delay. [ABSTRACT FROM AUTHOR]

• A BOG buffer tank and a control strategy is proposed to optimize the liquefaction process and can maintain the stability of the system. • The inlet gas volume increases by 12.2% and system specific energy consumption is reduced by 5.7% compared with the reference process. • The results of the simulation data provide an identifiable scale demarcation for the control strategy. • The optimal intake ratio exists which can be more responsively adjusted and adapted to process fluctuations in actual operation. The re-liquefaction of BOG is a necessary part of the safety and security of LNG cargo ships. And the volatility of BOG will fluctuate with the sea conditions of ship transportation, so how to deal with the fluctuation of the re-liquefaction system and improve the liquefaction capacity is a problem that cannot be ignored in the operation of the liquefaction system; In this paper, a BOG buffer tank is added to the Reverse Brayton Process. Moreover, a control strategy is proposed to optimize the liquefaction process. The proposed four possible operating conditions' efficiency,the specific energy consumption (SEC), liquefaction rate and main heat exchanger parameters were simulated and analyzed by using Aspen HYSYS software. According to the results, the specific energy consumption of the basic re-liquefaction process is 1.329 kWh/kg LNG , which is 5.7% less than that of the reference process; In the study of flow fluctuation, after adopting the control strategy, the specific energy consumption of the whole process is 1.29 kWh/kg LNG , with 15.6% efficiency and 99.5% liquefaction rate. The whole system can be maintained at a low specific energy consumption level when the feed gas volume is fluctuating. The analyses of various BOG composition and the parameters of the main heat exchanger show that the regulation of the inlet gas volume can make the primary re-liquefaction process flexible and maintain the heat exchanger in a good working condition; Even if the system is in a worse working condition, the inlet gas volume can be improved by 12.2% compared with the reference process. [ABSTRACT FROM AUTHOR]

In Germany, the systematics of humus forms has been developed, which is mainly based on morphological characteristics and has been proven via detailed long-term observation. The humus form systematics presented here is an update based on a new approach, clarifying the hierarchical structure into divisions, classes, types, and subtypes. New diagnostic horizons and transition horizons are introduced, uniquely characterising types and subtypes. This paper holds that the humus form is not only a product of decomposition, humification, and bioturbation but also serves as habitat for soil organisms. The processes and the habitat are shaped by soil-forming factors with the main factor being soil water conditions. Thus, on the first level of systematics, aeromorphic and aerohydromorphic as well as hydromorphic humus forms are differentiated. Many different features of the organic layers and the mineral topsoil can be observed in forests, open grasslands, the mountain zone above the tree line, and natural fens and bogs, as well as degraded peatlands. Features shaping the humus form, such as the proportion of organic fine material and packing of the organic matter as well as the structure of the mineral soil, have now been unambiguously described. However, site-specific soil-forming factors result in typical organic matter characteristics of individual horizons and typical combinations of different horizons. This relationship is illustrated using descriptions of distinct humus forms. [ABSTRACT FROM AUTHOR]

A CO2 boiled off gas (CO2 BOG) reliquefaction system using liquid ammonia cold energy is designed to solve the problems of fuel cold energy waste and the large power consumption of the compressor in the process of CO2 BOG reliquefaction on an ammonia-powered CO2 carrier. Aspen HYSYS is used to simulate the calculation, and it is found that the system has lower power consumption than the existing reliquefaction method. The temperature of the heat exchanger heater-1 heat flow outlet node (node C-4) is optimised, and it is found that, with the increase of the node C-4 temperature, the power consumption of the compressor gradually increases, and the liquefaction fraction of CO2 BOG gradually decreases. Under 85% conditions, when the ambient temperature is 0°C and the temperature of node C-4 is -9°C, the liquid fraction of CO2 BOG reaches the maximum, which is 74.46%, and the power of Compressor-1 is the minimum, which is 40.90 kW. According to this, the optimum temperature of node C-4 under various working conditions is determined. The exergy efficiency model is established, in an 85% ship working condition with the ambient temperature of 40°C, and the exergy efficiency of the system is the maximum, reaching 59.58%. Therefore, the CO2 BOG reliquefaction system proposed in this study could realise effective utilisation of liquid ammonia cold energy. [ABSTRACT FROM AUTHOR]

Detailed information on amphibian assemblages associated with high-elevation (>1000 m above sea level) bogs in southwest Virginia's Balsam Mountains is lacking in the literature, with few historic surveys focused on these habitats. We compared amphibian diversity at two such bogs in Grayson Highlands State Park during 2021 and 2022, finding 11 total amphibian species and 172 total individuals. Amphibians at both sites were restricted to salamanders typically associated with headwater stream and seep communities and adjacent forests, with no anurans or poolbreeding salamanders observed. Assemblages also varied between sites, which were similar in wetland character but located within differing upland contexts. Desmognathine salamanders dominated encounters at a bog nested within heavily-disturbed, cleared bald habitat, with a more diverse assemblage containing several species adapted to high-elevation forests found at a nearby site nested within northern hardwood and spruce-fir forests. We additionally uncovered several Weller's Salamanders (P. welleri) at the latter site, confirming the species' presence in Grayson Highlands State Park and expanding its habitat associations to sphagnum substrate within highelevation bogs. Our dataset provides a preliminary inventory of amphibians from this understudied habitat type and a foundation for more detailed investigation into habitat associations of individual species of concern. [ABSTRACT FROM AUTHOR]

During more than five centuries of human colonization, 50% of original peatlands in Azores have been destroyed or degraded, mainly due to pasture use, resulting in landscape changes and a loss of ecosystem biodiversity and services. This study aims to identify the most effective measures in the recovery and to detect initial responses (2 years). These are the first restoration experiments, carried out in a background of complete absence of strategies adapted for Azores pastured peatlands. In a post‐pastured peatland, 24 experiments were implemented, repeated in more degraded (northern) and more natural (southern) areas. The experiments were combinations of restoration measures, with the introduction of Juniperus brevifolia, Calluna vulgaris, and Sphagnum palustre and the use of management techniques to control herbaceous cover (alien‐rich herbaceous cover competing with Sphagnum or peatland natural shrubs): intensive and extensive grazing and grass cutting. Principal response curves and redundancy analyses were used to assess changes in the flora and the physicochemical parameters. Globally there was an increase in Sphagnum cover and a decrease in herbaceous species. This was accompanied by an increase in organic matter and a decrease in nitrogen. In more natural parcels (large artificially divided areas where different experiments were implemented), the most positive tendencies were associated with the combination of J. brevifolia planting and grass cutting. In more degraded areas, treatments had a lower impact, as the results tended to be similar to the control, pointing to an important natural regenerative succession dynamic that overlapped the response to the implemented treatments. [ABSTRACT FROM AUTHOR]

In fire‐prone ecosystems, knowledge of vegetation–fire–climate relationships and the history of fire suppression and Indigenous cultural burning can inform discussions of how to use fire as a management tool, particularly as climate continues to change rapidly. On Wiisaakodewan‐minis/Stockton Island in the Apostle Islands National Lakeshore of Wisconsin, USA, structural changes in a pine‐dominated natural area containing a globally rare barrens community occurred after the cessation of cultural burning by the Indigenous Ojibwe people and the imposition of fire‐suppression policies, leading to questions about the historical role of fire in this culturally and ecologically important area. To help understand better the ecological context needed to steward these pine forest and barrens communities, we developed palaeoecological records of vegetation, fire, and hydrological change using pollen, charcoal, and testate amoebae preserved in peat and sediment cores collected from bog and lagoon sediments within the pine‐dominated landscape. Results indicated that fire has been an integral part of Stockton Island ecology for at least 6000 years. Logging in the early 1900s led to persistent changes in island vegetation, and post‐logging fires of the 1920s and 1930s were anomalous in the context of the past millennium, likely reflecting more severe and/or extensive burning than in the past. Before that, the composition and structure of pine forest and barrens had changed little, perhaps due to regular low‐severity surface fires, which may have occurred with a frequency consistent with Indigenous oral histories (~4–8 years). Higher severity fire episodes, indicated by large charcoal peaks above background levels in the records, occurred predominantly during droughts, suggesting that more frequent or more intense droughts in the future may increase fire frequency and severity. The persistence of pine forest and barrens vegetation through past periods of climatic change indicates considerable ecological resistance and resilience. Future persistence in the face of climate changes outside this historical range of variability may depend in part on returning fire to these systems. [ABSTRACT FROM AUTHOR]

The names Lubainis and Vanaenia recorded in inscriptions from Namur have long been proposed to preserve evidence that supports the reconstruction of the stem of the Germanic weak class-III verbs as originally featuring a diphthong *-ai-. Cognates of the Gothic weak class-III verb weihan ›to consecrate‹ have similarly been widely held to be preserved in two inscriptions rescued over a century ago from the Danish votive bogs. The attested forms wiju and wija suggest the development of a first-person singular present indicative ending -jǣ, much as would be expected of a weak class-III verb in Northwest Germanic. Gothic weihan ›to consecrate‹ is a factitive, however, and wiju and wija appear to have developed in a manner contrary to that assumed in recent accounts of the morphological origin of the weak class-III verbs. [ABSTRACT FROM AUTHOR]

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Rationale: Land‐use changes, e.g., forestry drainage, modify the characteristics of peatland soil and affect the peatland carbon (C) balance. Peat soil nutrient status, related mainly to the original peatland type, also has an impact on the C balance after drainage, as observed earlier at the ecosystem scale for two forestry‐drained sites in Southern Finland. Here the aim was to compare the soil CO2 fluxes from the two sites, nutrient‐poor and nutirent‐rich forestry‐drained peatlands, and study the effect of plant photosynthates on the decomposition of peat C. Therefore, the respiration rates and priming effect (PE) of peat soils with variable nutrient status were examined in the laboratory. Methods: Half of the samples were labelled with 13C‐glucose to study the effect of fresh C addition on the soil decomposition. The 13CO2‐samples were analysed with isotope ratio mass spectrometry. A two‐pool mixing model was applied to separate the soil‐ and sugar‐derived respirations and to determine the PE. Results: The nutrient‐rich peat soil respired generally more than the nutrient‐poor peat. A negative PE was observed in both peat soils, suggesting that the addition of fresh C did not increase the soil decomposition, but on the contrary decreased it. The negative PE was significantly more pronounced in nutrient‐poor peat soil than in the nutrient‐rich peat treatments, suggesting that the higher nutrient availability suppresses the negative PE. Conclusions: These results imply that microbes prefer utilizing fresh C instead of old C in the short term and that the peat decomposition is suppressed in the presence of fresh C inputs from vegetation at forestry‐drained peatlands. These effects are even stronger in peat soils with less nutrients available. Ecosystem scale and soil process models could be improved with the help of these results. [ABSTRACT FROM AUTHOR]

Peatlands store disproportionally large amounts of carbon per unit area, a function that is dependent on maintaining high and stable water tables. Climate change is likely to negatively impact carbon storage in peatlands, in part due to increases in vapour pressure deficit (VPD) driving higher evaporation (E) rates. However, the response of E to increasing VPD depends on the dominant vegetation type within peatlands. In this study, we used multiple years of eddy covariance (EC) measurements to compare E regimes at two peatlands with contrasting vegetation types – Kopuatai bog in Aotearoa New Zealand, dominated by the vascular jointed wire rush Empodisma robustum , and Mer Bleue bog in Canada, a 'typical' shrub and moss-dominated Northern Hemisphere peatland. We examined seasonal variability in E and equilibrium E (E eq), energy balance partitioning, and the response of E, evaporative fraction (EF), and canopy conductance (g c) to VPD. Mean annual E was 45 % lower than mean annual E eq at Kopuatai, but only 16 % lower at Mer Bleue, demonstrating much greater limitations on E at Kopuatai. In addition, the mean midday (10:00–14:30) dry canopy Bowen ratio (β) at Kopuatai was 1.96, compared to 0.77 at Mer Bleue; therefore, the sensible heat flux (H) dominated over the latent heat flux (LE) at Kopuatai, and vice versa at Mer Bleue. The responses of E , EF, and g c to increasing VPD at Kopuatai differed from those at Mer Bleue in a way that resulted in stronger limitations on E above ~0.7 kPa at the former bog. The observed limitations at Kopuatai were attributed to strong stomatal control by E. robustum due to the rapid decrease in g c with increasing VPD, however surface E could also be limited by its dense standing litter. At Mer Bleue, however, E was only weakly limited at VPD > 2 kPa, likely due to weak stomatal control over transpiration by the sparse shrub canopy and relatively large surface E from Sphagnum carpets. As such, the results of this study suggest that E. robustum drives a greater "hydrological resistance" to increasing VPD than the vegetation at Mer Bleue, leading to greater water retention at Kopuatai. This may enable greater resilience of the carbon sink function at Kopuatai to climatic warming and drying than at Mer Bleue. [ABSTRACT FROM AUTHOR]

This paper explores the source of boil off gas (BOG) at liquefied natural gas (LNG) receiving station and calculates the amount of BOG required to be treated. It is obtained that the amount of BOG required to be treated under unloading and non-unloading conditions is 15.837 t/h and 2.863 t/h, respectively. The composition of the BOG treatment system and the recondensation process are studied. Optimize the recondensation process and BOG treatment system by improving heat transfer efficiency of the recondenser, directly exporting low-pressure BOG, and controlling tank pressure. The parameters such as the amount of LNG required for BOG entering the recondenser, the liquid level of the recondenser and the pressure at the top and bottom of the recondenser are analyzed. The flow of LNG into the recondenser is adjusted by the regulator. The bottom pressure of the recondenser is controlled by adjusting the PV02A/B opening. The load of the BOG compressor is adjusted to adjust the liquid level of the recondenser to achieve the optimization of the liquid level control. [ABSTRACT FROM AUTHOR]

To understand the variability of methane (CH4) fluxes between a temperate mid-altitude Sphagnum-dominated peatland and the atmosphere, we monitored simultaneously eddy covariance, hydrometeorological and physical parameters between April 2019 and December 2021. The site was a CH4 source for the atmosphere, with a cumulative emission of 23.9 ± 0.6 g C m−2 year−1. At the interannual scale, deeper water table during vegetation growth periods resulted in lower CH4 fluxes (FCH4), and reciprocally. Furthermore, the seasonal temperature variation in the anaerobic peat layer was a good predictor for FCH4. However, while the lowest temperatures occurred between December and February, the lowest FCH4 were observed between March and May, with around 30% of negative FCH4. Indeed, the fastest increase in temperature of the aerobic layer likely stimulated methanotrophy at the expense of methanogenesis. Negative FCH4, systematically observed at midday, were concurrent with high photon flux densities, latent heat fluxes and net negative ecosystem CO2 exchanges, suggesting the control of photosynthesis over CH4 oxidation. Moreover, our results highlighted marked diurnal cycles with FCH4 maximal at night and minimal at midday for all seasons. This diurnal cyclicity is in opposition to what is typically known for peatlands dominated by vascular plants. Physical parameters, such as soil surface temperature and sensible heat fluxes, likely contribute to this diurnal FCH4 cyclicity and require further investigation. Our study thus demonstrates that diurnal variations in FCH4 must be considered before upscaling to seasonal or annual cycles, along with the effect of vegetation on CH4 transfer and oxidation processes. [ABSTRACT FROM AUTHOR]

Peatland degradation through drainage and peat extraction have detrimental environmental and societal consequences. Rewetting is an option to restore lost ecosystem functions, such as carbon storage, biodiversity and nutrient sequestration. Peat mosses (Sphagnum) are the most important peat‐forming species in bogs. Most Sphagnum species occur in nutrient‐poor habitats; however, high growth rates have been reported in artificial nutrient‐rich conditions with optimal water supply.Here, we demonstrate the differences in nutrient dynamics of 12 Sphagnum species during their establishment in a 1‐year field experiment at a Sphagnum paludiculture area in Germany. The 12 species are categorized into three groups (slower‐, medium‐ and fast‐growing). Establishment of peat mosses is facilitated by constant supply of nutrient‐rich, low pH, and low alkalinity surface water.Our study shows that slower‐growing species (S. papillosum, S. magellancium, S. fuscum, S. rubellum, S. austinii; often forming hummocks) displayed signs of nutrient imbalance. These species accumulated higher amounts of N, P, K and Ca in their capitula, and had an elevated stem N:K quotient (>3). Additionally, this group sequestered less C and K per m2 than the fast and medium‐growing species (S. denticulatum, S. fallax, S. riparium, S. fimbriatum, S. squarrosum, S. palustre, S. centrale). Lower lawn thickness may have amplified negative effects of flooding in the slower‐growing species.We conclude that nutrient dynamics and carbon/nutrient sequestration rates are species‐specific. For bog restoration, generating ecosystem services or choosing suitable donor material for Sphagnum paludiculture, it is crucial to consider their compatibility with prevailing environmental conditions. [ABSTRACT FROM AUTHOR]

The Drentsche Aa valley system in the glacial sandy landscape of the north-eastern Netherlands, is one of the many regional drainage systems in the north-western to central European Lowlands. Following deep incision in the Weichselian, ca 7 m of eutrophic peat has accumulated in the lower to middle reaches of the valley system in the Holocene, completely filling the Weichselian incision. We reconstructed the rate of water-level rise controlling peat growth at three locations in the valley system (representing the upper, middle and lower reaches), using 14C peat dates from compaction-free sampling sites on the sloping valley margin where the peat directly overlies the sandy Pleistocene subsurface. The 14C dates enabled the construction of curves showing the water-level evolution at each location. Our results show variable rates of Holocene peat growth in the valley system in response to different drivers of hydrological change: a strong increase in annual precipitation (onset Holocene), a decrease in evapotranspiration (10,000–8000 cal. years BP) and relative sea-level rise (after ~4500 cal. years BP). Because the identified hydrological controls on peat growth are regional, they probably ruled Holocene peat growth in many peat-filled valley systems in the north-western to central European Lowlands. Currently, there is growing attention for these valley systems in the context of European nature restoration efforts and climate change adaptation and mitigation measures. The present study underscores that large-scale hydrological measures outside the valley system are needed for restoration of degraded valley peatlands. [ABSTRACT FROM AUTHOR]

The purpose of the study was to estimate invasion levels of alien plants in various natural and anthropogenic habitats of the Middle Urals in two urbanization manifestation variants: (1) within the boundaries of a large city; and (2) in suburban areas. In total, 965 geobotanical relevés produced in natural (bogs, floodplains, petrophytic areas, meadows, and forests) and anthropogenic (wastelands, public gardens, and residential areas) habitats were analyzed. Natural habitats were surveyed within the boundaries of a large city and in its suburban zone (at distances of 30–40 km from the city). Invasion levels were determined based on the number and proportion of alien (adventitious) species in the description. Both in suburban and urban conditions, the lowest numbers of alien species were recorded in bog habitats (on average, 0–0.6 species per description); while the largest numbers, in anthropogenic habitats (on average, 9.8–17.6 species per description). Outside the city, average numbers of alien species in natural habitats (except for bogs) varied in the range of 1.0–2.8 species per description; within the city, 3.8–6.2 species per description. In natural habitats (except for bogs), average shares of alien species varied in the range of 1.8–5.6% outside the city and in the range of 8.1–16.2% within the city; in anthropogenic habitats, they varied in the range of 22.8–32.8%. Suburban and urban wastelands did not differ in numbers and proportions of alien species (10.3 and 12.9 species per description and 25.3 and 30.2%, respectively). Invasion levels identified in suburban areas are consistent with those recorded in Europe. [ABSTRACT FROM AUTHOR]

There are limited data for greenhouse gas (GHG) emissions from smallholder agricultural systems in tropical peatlands, with data for non‐CO2 emissions from human‐influenced tropical peatlands particularly scarce. The aim of this study was to quantify soil CH4 and N2O fluxes from smallholder agricultural systems on tropical peatlands in Southeast Asia and assess their environmental controls. The study was carried out in four regions in Malaysia and Indonesia. CH4 and N2O fluxes and environmental parameters were measured in cropland, oil palm plantation, tree plantation and forest. Annual CH4 emissions (in kg CH4 ha−1 year−1) were: 70.7 ± 29.5, 2.1 ± 1.2, 2.1 ± 0.6 and 6.2 ± 1.9 at the forest, tree plantation, oil palm and cropland land‐use classes, respectively. Annual N2O emissions (in kg N2O ha−1 year−1) were: 6.5 ± 2.8, 3.2 ± 1.2, 21.9 ± 11.4 and 33.6 ± 7.3 in the same order as above, respectively. Annual CH4 emissions were strongly determined by water table depth (WTD) and increased exponentially when annual WTD was above −25 cm. In contrast, annual N2O emissions were strongly correlated with mean total dissolved nitrogen (TDN) in soil water, following a sigmoidal relationship, up to an apparent threshold of 10 mg N L−1 beyond which TDN seemingly ceased to be limiting for N2O production. The new emissions data for CH4 and N2O presented here should help to develop more robust country level 'emission factors' for the quantification of national GHG inventory reporting. The impact of TDN on N2O emissions suggests that soil nutrient status strongly impacts emissions, and therefore, policies which reduce N‐fertilisation inputs might contribute to emissions mitigation from agricultural peat landscapes. However, the most important policy intervention for reducing emissions is one that reduces the conversion of peat swamp forest to agriculture on peatlands in the first place. [ABSTRACT FROM AUTHOR]

Uncertainty remains over local‐scale responses of ecotonal Amazonian forests to middle Holocene drying due to the scarcity, and coarse spatial resolution, of lacustrine pollen records. This paper examines the palaeoecological potential of soil phytoliths, stable carbon isotopes and charcoal for capturing local‐scale ecotonal responses of different types of Bolivian Amazonian forest to middle Holocene climate change. Soil pits 1 m deep were dug at ecotones between rainforest, dry forest, Chaco woodland and savannah, and sampled at 5–10 cm resolution. Both phytolith and stable carbon isotope records indicate stability of dry forest–savannah ecotones over the last ca. 6000 years, despite middle Holocene drought, revealing the dominance of edaphic factors over climate in controlling this type of ecotone. In contrast, δ13C data reveal that rainforest–savannah ecotones were more responsive to climate change, with rainforest likely replaced by drought‐tolerant dry forest or savannah vegetation during the mid‐Holocene, consistent with regional‐scale lacustrine pollen records. However, such shifts are not apparent in most of our phytolith records due to insufficient taxonomic resolution in differentiating rainforest from dry forest. Charcoal data show that ecotonal dry forests experienced greater fire activity than rainforests and that recent high fire activity at all forest sites is unprecedented since at least the middle Holocene. [ABSTRACT FROM AUTHOR]

Active evaporite karst processes in the Baltic states are associated with a few relatively small regions where gypsum rocks can be found close to the Earth's surface. One of these areas lies in the vicinity of the Pandu bog. However, such a possibly active karst region, which is covered by peat and in which the mapping of karst formations is complex, has not been previously investigated. In this study, we present a buried and peat‐filled karst cover‐collapse sinkhole mapping approach that involves a combination of ground‐penetrating radar (GPR), electrical resistivity tomography (ERT) and conventional boreholes. A detailed map of the bog's substratum topography was constructed from a geophysical surveying dataset. It reveals 15 distinctly expressed sinkholes with diameters of several tens of metres. Overall, 140 potential sinkholes were also mapped using remote sensing data in the vicinity of the bog. Higher electrical resistivity anomalies were identified inside the peat; they coincide with scatter‐free zones in GPR data and water layers in boreholes. Highly disturbed internal peat layering was also detected in these sinkholes. It is suggested that these water layers and disturbed peat layering may have formed due to the subsidence of the lower peat layers, and thus they represent relatively younger sinkholes. This is also supported by evidence from orthophoto maps, which showed the formation and disappearance of surficial lakes and depressions on the bog surface. Our results revealed the presence of active and widespread karst processes under the bog that have not been previously noticed despite the fact that they have implications for the assessment of geohazards in this area. [ABSTRACT FROM AUTHOR]

Understanding the landscape evolution and human-environmental interaction within it is one of the key tasks of early Holocene research. As mobile hunter–gatherers leave few traces of structural organization, understanding their habitats is relevant for comprehending these people. Rarely does the spatial distribution of artifacts correspond to the real pattern of past human activity, but rather shows the pattern of identified artifacts. Geophysical investigations try to fill this gap and have been applied increasingly in archaeological prospection delivering landscape reconstruction, which are verified and fine-tuned using corings and excavations. Despite promising 3D models, a tool to predict the location of undiscovered former human presence and the conditions which influenced people to move across the landscape is not well developed. The primary goal of this paper is to present a methodology for connecting spatial patterns of past human activity based on archaeological and geophysical data. We discuss different GPR (ground-penetrating radar) facies classified at the shoreline of the former Lake Duvensee and geomorphological variables, which leads to the possibility of understanding where and why people chose preferred areas to settle on former islands. We also demonstrate that Mesolithic hunter–gatherer groups preferred dry areas with access to open water for short-term campsites and flatter and more protected areas for specialized and repeatedly occupied campsites. The cardinal orientation of a campsite seems to be secondary to the local peat over-growing process and access to water. [ABSTRACT FROM AUTHOR]

Sustainable peatland management is a global environmental governance challenge given peat's carbon storage. Peatlands worldwide are sites of contested demands between stakeholders with distinct management priorities. In the United Kingdom, peatland management is a focus of political interest for nature-based solutions (NBS), causing tensions with land managers who feel their traditional knowledge is undervalued. Using Q-method (a semi-quantitative method for clarifying distinct viewpoints) with estate managers, gamekeepers, farmers, and employees of land-owning organisations, we explored perceptions around changing upland management in the Yorkshire Dales. Land managers hold strong values of ownership, aesthetics, and stewardship. The prospect of changing management causes fears of losing these relational values alongside instrumental values. Yorkshire Dales stakeholders agreed on NBS aims (reducing flooding, limiting wildfires, protecting wild birds), but disagreed on methods to achieve these. Our research supports engaging local stakeholders at all stages of peatland protection schemes to minimise resentment towards top-down management. [ABSTRACT FROM AUTHOR]

This study discusses the timing and maximum flood level of the Nedre Glomsjø outburst flood, Norway, based on sediment records retrieved from 15 bog and lake basins located close to the purported maximum flooded level. The sediment records in 12 of the basins consist of a distinct light‐coloured silty bed that is correlated to the outburst‐flood‐deposited 'Romerike Silt Bed' identified elsewhere in the region. The silt bed is recorded in basins up to a certain elevation and is absent above this level. The new maximum flood level inferred from the basin sediment records exceeds the established landform‐induced palaeostage indicators by 5–10 m. The data indicate a higher maximum flood level and larger inundation area than previously suggested and highlight the importance of acquiring a wide range of geological data when reconstructing palaeofloods. Radiocarbon dates of terrestrial macrofossils found stratigraphically above and below the Romerike Silt Bed suggest that the glacial lake Nedre Glomsjø outburst flood occurred between 10.5 and 10.3 cal. ka BP. The new and well‐constrained timing of the outburst flood is beneficial for reconstructing regional deglaciation and provides a precise age for the Romerike Silt Bed chronostratigraphical marker, which is of value for studies in SE Norway and adjacent regions. [ABSTRACT FROM AUTHOR]

Northern peatlands store approximately one-third of terrestrial soil carbon. Climate warming is expected to stimulate the microbially mediated degradation of peat soil organic matter (SOM), leading to increasing greenhouse gas (GHG; carbon dioxide, CO2; methane, CH4) production and emission. Porewater dissolved organic matter (DOM) plays a key role in SOM decomposition; however, the mechanisms controlling SOM decomposition and its response to warming remain unclear. The temperature dependence of GHG production and microbial community dynamics were investigated in anoxic peat from a Sphagnum -dominated peatland. In this study, peat decomposition, which was quantified by GHG production and carbon substrate utilization is limited by terminal electron acceptors (TEA) and DOM, and these controls of microbially mediated SOM degradation are temperature-dependent. Elevated temperature led to a slight decrease in microbial diversity, and stimulated the growth of specific methanotrophic and syntrophic taxa. These results confirm that DOM is a major driver of decomposition in peatland soils contains inhibitory compounds, but the inhibitory effect is alleviated by warming. [ABSTRACT FROM AUTHOR]

Comprehensive study of the lagoon terrace section at the apex of Amur Bay has made it possible to identify sharp short-term cooling events at 4450, 2870–2510, 1740–1200, and 680–150 cal BP that are compared to cold events in many regions around the world. The reconstructions are based on the results of diatom, botanical, and palynological analyses. The age–depth model is generated by the Bacon program using radiocarbon dating and tephrostratigraphy. Tephra B-Tm from the caldera-forming eruption of Baitoushan volcano was found in the section. The section selected as a natural archive has its own specifics. In contrast to the mountainous areas and river basins, where the climate became dry 3320–3050 years ago due to a sharp decrease in the intensity of the summer monsoon, coastal lacustrine–boggy sequences developed in constantly waterlogged conditions. This made it possible to identify short-term dry events that correlate well with the global climatic rhythm caused by the decrease in solar radiation. The decrease in moisture was closely related to the influence of the ocean: the intensity of tropical cyclogenesis. The shallowing of the lagoon during the decline of the low-amplitude transgression, intensified by the weakening of the summer monsoon, led to a change from terrigenous to organogenic sedimentation at about 3460 years ago. The cooling event 2870–2510 years ago had the most complex structure with sharp changes in moisture. Change in the course of bog-forming processes around 1740 years ago associated with the activation of floods, which caused periodic flooding of the peat deposits in the vast estuary zone of the Razdolnaya River, led to the disappearance of the tree layer and the development of a grass bog. In general, the regional conditions were dry until the Medieval Warm Period. The response of the landscapes to cooling is identified: the role of broadleaved species in the forest vegetation of the low mountains decreased, and the participation of plants preferring less inundated habitats in the development of local landscapes increased. The Little Ice Age is the exception of the cold events, which was wet and characterized by frequent floods. The meridional transport of moist air masses from the ocean to the continent became more active during that time. [ABSTRACT FROM AUTHOR]

At present, the known populations of Lycaena helle from Romania are found at a lower altitude than those from Western and Central Europe. Besides land-use changes, climate warming severely threatens this specie that prefer humid and cool habitats. Withdrawal to higher altitudes is also restricted by the species' low dispersal ability. Therefore, the future of the Romanian population is uncertain. While implementing a peatlands restoration project in the northeastern part of the country, we investigated the local invertebrate fauna around a bog woodland from Dornelor Depression (Suceava County). Here we found a mosaic of wet habitats sheltering a violet copper population. This population was mentioned long ago, representing the first recorded instance of this species in present-day Romania. The violet copper butterfly has not been spotted in the area since the initial record was published in 1897, and current literature only refers to it as historical data from the Dorna Depression. We describe the habitat occupied by this population, bring up to date the specie's distribution, and prompt for the designation of a special area of conservation for this European protected species. [ABSTRACT FROM AUTHOR]

The composition of the biota is dynamic and changes for many reasons, making biodiversity research relevant. Studies of rare species that are most vulnerable to anthropogenic pressures are of particular importance. Although the Mozh River flows through the central part of the Kharkiv Region, its valley remains understudied, especially the pine forests and their rare plants. The results of the current study include data from our field research, revision of the Herbarium of V.N. Karazin Kharkiv National University (CWU), and literature sources from the second half of the 20th century to the present. This paper contains an annotated list of 35 species of vascular plants. Each species is provided with the data on its geographical range, distribution in Ukraine, population status and its study history in the Kharkiv Region, conservation status, and the state of its population in the studied forests. We found the localities of two species included in Appendix I of the Bern Convention (Salvinia natans (L.) All. and Jurinea cyanoides (L.) Rchb. and six species included in the Red Data Book of Ukraine (Botrychium lunaria (L.) Sw., Pulsatilla pratensis (L.) Mill., Iris pineticola Klok., Neottia nidus-avis (L.) Rich., Neottia ovata (L.) Hartm., Tulipa quercetorum Klok. & Zoz). We also found 19 species rare in the Kharkiv Region (Lycopodium clavatum L., Athyrium filix-femina (L.) Roth, Ophioglossum vulgatum L., Campanula persicifolia L., Chimaphila umbellata (L.) W.P.C. Barton, Comarum palustre L., Hottonia palustris L., Rubus saxatilis L., Carex pseudocyperus L., etc.). Nine regionally rare plant species have the boreal range type; they occur at the southern limit of their distribution range which indicates the specificity of ecological and climatic conditions formed in the pine forests in the Mozh River valley. In addition, we found five species without conservation status, but they are rare in the region (Caltha palustris L., Catolobus pendulus (L.) Al-Shehbaz, Gratiola officinalis L., Lythrum hyssopifolia L., Rubus polonicus Barr. ex Weston), and, therefore, they are recommended to be included in the next edition of the Official List of the Regionally Rare Plants of the Kharkiv Region. Three species (Buglossoides czernjajevii (Klokov & Des.-Shost.) Czerep., Jacobaea andrzejowskyi (Tzvelev) B.Nord. & Greuter, Sedum album L.) were identified as understudied in the Kharkiv region due to the lack of or insufficient information on their distribution in the study area. [ABSTRACT FROM AUTHOR]

A comprehensive investigation of small mammal populations was conducted at the ecological research station situated in Khonin Nuga, located in the upper reaches of the Eroo River within the West Khentey Mountains, spanning a duration of 14 years, from 2000 to 2013. The methodology employed encompassed both pitfall trapping and markrecapture live trapping techniques. The findings documented the presence of seven distinct species, comprising six soricids and one Crocidura. Noteworthy among the soricids were Sorex caecutiens, Sorex daphaenodon, and Sorex isodon, which exhibited the highest levels of abundance, with Sorex roboratus also being frequently captured. Conversely, species such as Sorex minutissimus, Sorex tundrensis, and Crocidura shantungensis were comparatively less abundant, with sporadic or singular occurrences. Estimates of species diversity, derived through the rarefaction method, revealed a species richness of 7, aligning closely with the empirical data amassed throughout the survey period. The analysis further revealed that three predominant shrew species were consistently observed across all major habitats under scrutiny. Specifically, S. caecutiens, S. daphaenodon, and S. isodon exhibited heightened capture rates within the floodplain meadows and both dark and light coniferous forest plots, respectively. Among the less common species, discernible habitat preferences emerged; for instance, S. roboratus demonstrated a propensity for open grass bog plots, while S. minutissimus exhibited a preference for rocky slopes. Additionally, Crocidura shantungensis displayed a predilection for southern steppe slopes. Sparse instances of S. tundrensis were documented within the confines of small floodplain meadows along tributaries of the Eroo River. [ABSTRACT FROM AUTHOR]

Background and Aims Sphagnum (peatmoss) comprises a moss (Bryophyta) clade with ~300–500 species. The genus has unparalleled ecological importance because Sphagnum -dominated peatlands store almost a third of the terrestrial carbon pool and peatmosses engineer the formation and microtopography of peatlands. Genomic resources for Sphagnum are being actively expanded, but many aspects of their biology are still poorly known. Among these are the degree to which Sphagnum species reproduce asexually, and the relative frequencies of male and female gametophytes in these haploid-dominant plants. We assess clonality and gametophyte sex ratios and test hypotheses about the local-scale distribution of clones and sexes in four North American species of the S. magellanicum complex. These four species are difficult to distinguish morphologically and are very closely related. We also assess microbial communities associated with Sphagnum host plant clones and sexes at two sites. Methods Four hundred and five samples of the four species, representing 57 populations, were subjected to restriction site-associated DNA sequencing (RADseq). Analyses of population structure and clonality based on the molecular data utilized both phylogenetic and phenetic approaches. Multi-locus genotypes (genets) were identified using the RADseq data. Sexes of sampled ramets were determined using a molecular approach that utilized coverage of loci on the sex chromosomes after the method was validated using a sample of plants that expressed sex phenotypically. Sex ratios were estimated for each species, and populations within species. Difference in fitness between genets was estimated as the numbers of ramets each genet comprised. Degrees of clonality [numbers of genets/numbers of ramets (samples)] within species, among sites, and between gametophyte sexes were estimated. Sex ratios were estimated for each species, and populations within species. Sphagnum -associated microbial communities were assessed at two sites in relation to Sphagnum clonality and sex. Key Results All four species appear to engage in a mixture of sexual and asexual (clonal) reproduction. A single ramet represents most genets but two to eight ramets were dsumbers ansd text etected for some genets. Only one genet is represented by ramets in multiple populations; all other genets are restricted to a single population. Within populations ramets of individual genets are spatially clustered, suggesting limited dispersal even within peatlands. Sex ratios are male-biased in S. diabolicum but female-biased in the other three species, although significantly so only in S. divinum. Neither species nor males/females differ in levels of clonal propagation. At St Regis Lake (NY) and Franklin Bog (VT), microbial community composition is strongly differentiated between the sites, but differences between species, genets and sexes were not detected. Within S. divinum , however, female gametophytes harboured two to three times the number of microbial taxa as males. Conclusions These four Sphagnum species all exhibit similar reproductive patterns that result from a mixture of sexual and asexual reproduction. The spatial patterns of clonally replicated ramets of genets suggest that these species fall between the so-called phalanx patterns, where genets abut one another but do not extensively mix because of limited ramet fragmentation, and the guerrilla patterns, where extensive genet fragmentation and dispersal result in greater mixing of different genets. Although sex ratios in bryophytes are most often female-biased, both male and female biases occur in this complex of closely related species. The association of far greater microbial diversity for female gametophytes in S. divinum , which has a female-biased sex ratio, suggests additional research to determine if levels of microbial diversity are consistently correlated with differing patterns of sex ratio biases. [ABSTRACT FROM AUTHOR]

Availability of reactive nitrogen (N r) is a key control on carbon (C) sequestration in wetlands. To complement the metabolic demands of Sphagnum in pristine rain-fed bogs, diazotrophs supply additional N r via biological nitrogen fixation (BNF). As breaking the triple bond of atmospheric N 2 is energy-intensive, it is reasonable to assume that increasing inputs of pollutant N r will lead to BNF downregulation. However, recent studies have also documented measurable BNF rates in Sphagnum-dominated bogs in polluted regions, indicating the adaptation of N 2 fixers to changing N deposition. Our aim was to quantify BNF in high-elevation peatlands located in industrialized central Europe. A 15 N 2 -tracer experiment was combined with a natural-abundance N-isotope study at three Sphagnum-dominated peat bogs in the northern Czech Republic in an attempt to assess the roles of individual BNF drivers. High short-term BNF rates (8.2 ± 4.6 g N m 2 d -1) were observed at Malé mechové jezírko, which receives ∼ 17 kg N r ha -1 yr -1. The remaining two peat bogs, whose recent atmospheric N r inputs differed from Malé mechové jezírko by only 1–2 kg ha -1 yr -1 (Uhlí r̆ská and Brumiště), showed zero BNF. The following parameters were investigated to elucidate the BNF difference: the NH 4+ -N / NO 3- -N ratio, temperature, wetness, Sphagnum species, organic-N availability, possible P limitation, possible molybdenum (Mo) limitation, SO 42- deposition, and pH. At Malé mechové jezírko and Uhlí r̆ská, the same moss species (S. girgensohnii) was used for the 15 N 2 experiment; therefore, the host identity could not explain the difference in BNF at these sites. Temperature and moisture were also identical in all incubations and could not explain the between-site differences in BNF. The N : P stoichiometry in peat and bog water indicated that Brumiště may have lacked BNF due to P limitation, whereas non-detectable BNF at Uhlí r̆ská may have been related to the 70-fold higher SO 42- concentration in bog water. Across the sites, the mean natural-abundance δ15 N values increased in the following order: atmospheric deposition (- 5.3 ± 0.3 ‰) < Sphagnum (- 4.3 ± 0.1 ‰) < bog water (- 3.9 ± 0.4 ‰) < atmospheric N 2 (0.0 ‰). Only at Brumiště was N in Sphagnum significantly isotopically heavier than in atmospheric deposition, possibly indicating a longer-term BNF effect. Collectively, our data highlight spatial heterogeneity in BNF rates under high N r inputs as well as the importance of environmental parameters other than atmospheric N r pollution in regulating BNF. [ABSTRACT FROM AUTHOR]

Fifty per cent of European peatlands are in a damaged state. While intact peatlands are natural carbon sinks, degraded sites release important amounts of greenhouse gases into the atmosphere, contributing to global warming. Restoration of the hydrological functionality of peatlands has proved to be an efficient tool to avoid these emissions. In France, Tuffnell & Bignon's ministerial report (2019) emphasized the need for peatlands 'integration into the National Low Carbon Strategy, targeting carbon neutrality by 2050. However, current knowledge regarding French peatlands' distribution and carbon stocks is insufficient and does not allow decision makers and managers to prioritize areas for restoration. The most complete database to date is the 1949 Atlas, an inventory of exploitable peat deposits that was conducted during WWII for peat exploitation as fuel. Until its digitalization, the latter database was archived and never used in a scientific study. It provides detailed information about peatland surfaces, peat thicknesses and carbon contents at that time. We estimated peat carbon stocks from French peatlands to be 111 Mt C in 1949 for 63,290 ha identified as peaty sites, the equivalent of 3% of the organic carbon contained in the upper 30 centimetres of French soils. 34% of this stock was held in Lower Normandy (37.7 Mt C) and 12% in the Picardy's region (13.0 Mt C), in large lowland peatlands. However, not all peatlands were prospected in the 1949 inventory and the characteristics of the prospected peatlands may have changed with anthropic disturbances of the last decades, such as draining or climate change. These first results highlight the need for a recent inventory of French peatlands and carbon stocks based on local data aggregation. Data from the 1949 Atlas could help constituting this new inventory but should be validated before being used to describe the present. [ABSTRACT FROM AUTHOR]