Peat Deposits Research Articles

Recent Gray Birch (Betula populifolia) Encroachment in Temperate Peatlands of Eastern North America

Numerous peatlands in eastern North America are currently experiencing an accelerated process of tree encroachment. Deciduous species, particularly gray birch, can sometimes form large, dense stands. Our objectives were to document the periods during which gray birch established in temperate peatlands of southern Quebec (Canada), and examine the factors that may have contributed to such massive establishment. We hypothesized that the abundant presence of gray birch is a relatively recent phenomenon associated with human activities that are creating conditions favorable to the establishment of this species. We analyzed dendrochronological, plant-macrofossil, aerial photographs and climatic data for 10 sites. All of the peatlands recently experienced a major increase in forest cover. The first sign of gray birch establishment dates back to the 1950s, although at over half of sites, establishment took place after 1980. Abundant macroremains of the species were found only in the upper portion of peat deposits. Birch encroachment most often occurred after a fire had spread through the peatland. Increasing agricultural and draining activities on the periphery of the peatlands, that coincides with drier climatic conditions, likely induced a drying out of the peat, thereby creating conditions propitious for fire and subsequent germination and growth of birch seeds.

Indicators of peat soil degradation in the Biebrza valley, Poland

Abstract Peat mineralisation leads to net loss of CO2 to the atmosphere, as well as to release of other elements from the decomposed soil organic matter (SOM) to groundwater. This results in the degradation of peat soils and the ecosystems they support. Here we evaluated the practical indicatory suitability of the existing and proposed new indices for the assessment of peat soil degradation in the Biebrza river valley encompassing, unique on European scale, peatland ecosystems. We studied relationships between soil organic carbon (SOC) and total nitrogen (Ntot), dissolved organic carbon (DOC) and dissolved organic nitrogen (DON) in a series of degraded peat soils in the Biebrza valley. Samples were taken from soils developed on peat deposits that varied in thickness and the degree of peat decomposition, from undegraded to highly mineralised peats. The relationships between changes in the SOC content and changes in the values of the remaining variables (SOM, Ntot, DOC, DON, C/N ratio), were statistically tested. Linear and non-linear regressions were used to establish the relationships amongst the variables examined. The losses of soil C and N occur independently and differ between stages of peat soil mineralisation. From our study, it results that the peat mineralisation intensity may be estimated based on the loss of SOC. We found that 1% loss of SOC corresponded to 1.028% loss of SOM, regardless of the degree of peat soil mineralisation, whereas SOM solubility, measured by the content of DOC, varied based on the intensity of peat soil mineralisation. The content of DOC decreased with the decrease in the SOC content, whereas the DOC/ SOC ratio increased depending on the intensity of peat decomposition. The C/N ratio is not a reliable indicator of peat mineralisation, because its values are driven not only by the nitrogen natively present in peat soils but also by nitrogen from external sources. The contents of SOC and Ntot did not decrease uniformly during peat decomposition because C and N show various mobility in the processes of SOM mineralisation. We found that the DOC/SOC ratio was most indicative of peat soil mineralisation intensity. © IOŚ-PIB

Mechanisms of accumulation of chemical elements in the peat deposit in east part of the Vasyugan Swamp (the Western Siberia)

The results of mineralogical-geochemical studies of the oligotrophic pine-fruticulose-sphagnum segment of the Vasyugan Swamp (West Siberia) in the winter of 2017 are presented. A mathematical model is developed for the depth distribution of chemical elements in water and acid extracts of peats, organo-mineral sediments, and inorganic soil. It is shown that two complex geochemical barriers related to the changes in filtration properties of soils and contributing to the formation and/or accumulation of Fe compounds and other chemical elements function in the peat deposit. The first (oxidizing, reduction, sulfide, and adsorption hydroxide) barrier is found approximately at a depth of 0.40-1.25 m; the second (alkaline carbonate and hydrolytic, adsorption hydroxide, clayey, and carbonate) barrier lies in the lower layer of the peat deposit (a depth of 2.25-2.50 m). The result obtained is important for understanding the production-destruction methane cycle.

Studying the dynamics of cosmic dust flux on the earth’s surface from peat deposits

Peat cores sampled from different climatic zones are studied. The petromagnetic and microprobe methods are used to find peat layers enriched with cosmic dust. It is established that the behavior of saturation isothermal remanent magnetization (SIRM) of peat deposits from the zones where the aeolian transfer of terrigenous particles is negligible can be used for studying the dynamics of the fall of cosmic matter on the Earth’s surface. The cosmic dust flux can be conditionally divided into the background and burst components. Here, the background flux of cosmic dust varies cyclically. The characteristic times of these cycles are about 100 years. The cyclicity in the background flux of cosmic material most clearly manifested itself in the interval of 1200 to 500 years ago. The most significant burst in the influx of cosmic material (by an order of magnitude above the background) is revealed in the layer that was formed about 5000 years ago. The microprobe studies established that the mineralogical content of cosmic dust differs between the background and burst fluxes.

Mechanisms of Accumulation of Chemical Elements in a Peat Deposit in the Eastern Part of Vasyugan Swamp (West Siberia)

The results of mineralogical–geochemical studies of the oligotrophic pine–fruticulose–sphagnum segment of Vasyugan Swamp (West Siberia) in the winter of 2017 are presented. A mathematical model is developed for the depth distribution of chemical elements in water and acid extracts of peats, organo-mineral sediments, and inorganic soil. It is shown that two complex geochemical barriers related to the changes in filtration properties of soils and contributing to the formation and/or accumulation of Fe compounds and other chemical elements function in the peat deposit. The first (oxidizing, reduction, sulfide, and adsorption hydroxide) barrier is found approximately at a depth of 0.40–1.25 m; the second (alkaline carbonate and hydrolytic, adsorption hydroxide, clayey, and carbonate) barrier lies in the lower layer of the peat deposit (a depth of 2.25–2.50 m). The result obtained is important for understanding the production–destruction methane cycle.

Studying the Dynamics of Cosmic Dust Flux on the Earth’s Surface from Peat Deposits

Peat cores sampled from different climatic zones are studied. The petromagnetic and microprobe methods are used to find peat layers enriched with cosmic dust. It is established that the behavior of saturation isothermal remanent magnetization (SIRM) of peat deposits from the zones where the aeolian transfer of terrigenous particles is negligible can be used for studying the dynamics of the fall of cosmic matter on the Earth’s surface. The cosmic dust flux can be conditionally divided into the background and burst components. Here, the background flux of cosmic dust varies cyclically. The characteristic times of these cycles are about 100 years. The cyclicity in the background flux of cosmic material most clearly manifested itself in the interval of 1200 to 500 years ago. The most significant burst in the influx of cosmic material (by an order of magnitude above the background) is revealed in the layer that was formed about 5000 years ago. The microprobe studies established that the mineralogical content of cosmic dust differs between the background and burst fluxes.

Reconstruction of the Holocene Dynamics of Forest Fires in the Central Part of Meshcherskaya Lowlands According to Antracological Analysis

This paper presents a reconstruction of the Holocene dynamics of forest fires and their influence on vegetation in the central part of Meshcherskaya Lowland. The studies are based on macrocharcoal and pollen analyses and radiocarbon dating of peat deposits from the Studencheskoe peatland. According to the results, changes in the structure of the plant cover were largely determined by the fire regime during the Holocene. In the period of high forest-fire intensity (∼9200–6400 calendar years BP), the study area was occupied by birch-pine forests. The role of spruce and broad-leaved species in forest stands was increased in the period with a low frequency of forest fires (∼6400–1400 calendar years BP). The influence of fires on vegetation increased after 1400 calendar years BP due to human impact. The results show that periods of increased fire frequencies occurred before the human occupation of the area and were determined by climatic causes.

Ocena tempa osiadania odwodnionego torfowiska oraz weryfikacja równań empirycznych opisujących ten proces

The papers presents the soil surface subsidence rate of drained (1967–1971) peat deposit in 1978–2015 years. The very high differences of the rate was observed on relatively small area (15 ha). The subsidence rate was observed in the range from 0.06 to 1.56 cm·year–1. The percentage loss of the peat deposit thickness in the years 1978– –2015 in the analyzed area was varied and did not depend on the initial thickness of the peat deposit. It oscillated between 2 and approx. 44%. The obtained measured data were able to perform the verification of selected published in the literature empirical equations to predict the subsidence rate of soil surface of drained many years ago lowland peatlands.

The sequence at Carihuela Cave and its potential for research into Neanderthal ecology and the Mousterian in southern Spain

Hitherto unpublished 14C and 230Th234U determinations from Carihuela Cave (Granada province, Andalusia, Spain) raise a possibility of late survival here of Neanderthals and their Mousterian technocomplex into an advanced stage of the Late Pleistocene (MIS-3), when anatomically-modern humans with Upper Palaeolithic toolkits were penetrating the region, and when also several carnivore taxa competed for access to the cave. Previous palaeopalynological studies are reinforced by new pollen analyses of samples extracted from coprolites. The palaeoecological and sedimentological records bear comparison with new data from the Padul peat deposits in the Sierra Nevada, and are in line with the view that there was late persistence of the Mousterian in Granada. There is a pressing need for renewed international multidisciplinary research at Carihuela Cave, with up-to-date lithostratigraphical and dating techniques that can expand on results obtained from fieldwork undertaken by a previous generation of researchers. Carihuela Cave continues to hold out great promise for analysing Neanderthal palaeoecology during the Late Pleistocene up to the appearance in southeastern Iberian Peninsula of anatomically-modern Upper Palaeolithic people, particularly with regard to the earlier phases of the Middle Palaeolithic at the cave which await intensive excavation but apparently extend back in time to the last interglacial period.

Extending the applicability of the REVEALS model for pollen-based vegetation reconstructions to coastal lagoons

Quantitative reconstruction of past plant abundance from fossil pollen data is still a challenging task for palynologists. During the last decades, mechanistic methods have been developed to convert pollen assemblages from peat and lake deposits into vegetation abundance at regional and local scale. Coastal areas are particularly sensitive to climate and environmental hazards. Thus, quantitative estimates of past vegetation are important to better understand their history and address potential effects of future environmental changes. However, assumptions of the mechanistic models of pollen dispersal and deposition originally designed for near-circular lakes and bogs located inland are violated when applied to coastal sites because of different basin shape and wind direction distribution. This study investigates how to adapt a model of pollen dispersal and deposition developed for lakes to coastal lagoons. A new geometry is defined, and it is demonstrated how some of the major formulas from previous models can be used without any modification in this singular context.

FEATURES OF LIPID COMPOSITION OF SPHAGNUM AND TRUE MOSSES FROM VARIOUS NATURAL CLI-MATIC ZONES

A composition of 16 lipid samples of sphagnum and true mosses (Bryales) growing at an average annual temperature ranging from -9.1 °C to 1.5 °C is investigated by gas chromatography-mass spectrometry. The individual composition and content of n-alkanes, fatty n-acids and their esters, n-alkane-2-ones, aldehydes, farnesylfuranes, polycyclic aromatic hydrocarbons (PAHs), tocopherols, squalene, steroids, sesqui-, di- and triterpenoids of these mosses are determined. True mosses differ from sphagnum mosses in their lower content of n-alkanes, n-alkan-2-ones, n-aldehydes, tocopherols and cyclic terpenoids, and a higher content of PAHs. Campesterol prevails among steroids of true mosses, while stigmasterol and sitosterol dominate in sphagnum mosses. Sitosterol prevails in sphagnum mosses growing in areas with a negative average annual temperature. An increase in the temperature of the habitat results in a decrease in the relative content of n-alkanes with odd number of carbon atoms in the molecule in true mosses, and a slight decrease in their average chain length in sphagnum mosses. It is shown that terpenoids are the most dependent on natural habitat conditions of mosses. This is indicated by the content of squalene, sesqui- and diterpenoids, the ratio of hydrocarbons to oxygen-containing structures of cyclic triterpenoids, and that of compounds from series of perhydropicene and cyclopentapeperhydrochryzene. The increased humidity of habitat of a moss eliminates the effect of temperature. The stability of composition of n-alkanes and n-alkan-2-ones of sphagnum mosses developing under various conditions makes it possible to consider these compounds as potential chemotaxonomic markers of sphagnum mosses in peat deposits.

ANTIOXIDANTS IN LIPIDS OF PEATS AND PEAT-FORMING PLANTS

The paper presents the results of a study of antioxidant activity of lipids isolated from bioproducer plants and peats sampled from a deposit on spurs of the Vasyugan Swamp. Analysis of antioxidants (AOs) is performed via the gasometric method using a model reaction initiated by cymene oxidation. It is found out that oxidation inhibitors of two types differing in reactivity and antioxidant content are present in peat lipids. In fuscum peats of the same type, the amount of AOs changes insignificantly with an increase in the depth of occurrence. A decrease in AOs of the second type is observed for peats with a high degree of decay. 
 The experiments on plant humification in a peat deposit conducted during 2 years confirm the neoplasm of AOs of the second type, which is the result of microbiological activity. The content of lipids in plants after 2 years of humification is slightly increased, while the increase in AOs amount exceeding their content in peat lipids of the upper horizon is also observed. The depth of occurrence and the type of peat affect the content of AOs and the O/C ratio, as evidenced by the linear correlation dependence. The relationship between the antioxidant activity of lipids and the C/N ratio is not established.

Spatial-temporal changes in the peat resources of Ukraine

Information on peat stocks in the world as a whole is presented. The spatial and temporal changes in peat reserves in Ukraine are analyzed. The quantitative characterization of the distribution of peat deposits and peat reserves by types will be considered over a long period of research time. In the use of agriculture there are 7722 km2 of peat deposits, 2806 km2 of which are represented by depleted agricultural land, while the rest of the area is occupied by unproductive hayflowers, pastures, swamps and shrubs. In the use of forestry enterprises there are 1536 km2 of peat deposits, most of which are also drained. At present, the main reserves of peat are in the following oblasts: Volyn (21%), Rivne (18%), Chernihiv (12%), Kyiv (11%), Lviv (6%), Khmelnytsky (6%), Sumy (5%), Zhytomyr (4%), other regions — 4%. The number of fields, their areas are gradually decreasing, for each decade they decrease by 3–20%, depending on the rate of use and other factors. Rapid pace of transformation of drained peatlands, specificity of soil formation, peculiar microclimate, greenhouse effect of swamps, radioactive contamination, high adsorption capacity for pollutants, coagulation of soil colloids, wind and hydrothermal erosion, degradation and formation of badlands, re-waterlogging, cascade of piles on drained lands, untimely reclamation, pyrogenic threat, illegal extraction of minerals, natural radioactivity and radon emissions, methane emissions, greenhouse gas deposition, creation and peat meadows, forests, hunting areas, protection of wetlands and peatlands — is one of the main issues to be addressed by introducing a set of measures based on science-based concepts. The peatlands, besides the unique phyto-, zoo-, and landscape manifolds, carry out serious soil protection, hydroforming functions, provide greenhouse gas absorption, are peat deposits as conditionally regenerating organogenic fuels, fertilizers and chemical raw materials; these are important reserves of berries, medicinal herbs, peat deposits of valuable value. for paleoecological research. The necessity of development of drained peatlands of Ukraine for effective agricultural management as an indicator of environmental changes is determined. Depleted and spent peatlands require rehabilitation and reclamation. The main questions to be solved by introducing the complex of the most urgent measures on the basis of a scientifically grounded concept — the creation of cascades of reservoirs from fish breeding, cultivating bioenergetic crops (willow, miscanthus, etc.), laying berries (high boletus, cranberries of largeleafed), etc. are given.

Holocene paleoenvironmental changes reflected in peat and lake sediment records of Western Siberia: Geochemical and plant macrofossil proxies

This paper presents the first result of a study of two long-term natural archives in the southwestern part of the Western Siberian Plain. Bchron age models based on 17 AMS dates allowed us to determine a chronology of changes in properties of lake and peat deposits. Significant changes in the Holocene were identified according to geochemical indices, accumulation rates, and compositions of the plant macrofossils of sediment cores in Lake Kyrtyma and Oshukovskoe peat bog. Sediments with a low content of organic matter and maximum weathering accumulated in the Late Glacial, below the border of the Holocene. The transition to the Holocene manifested as a black organic gyttja with ostracods and marked warming ∼12–11.2 ka BP. At about 11.2–10.1 ka BP it was replaced by the Preboreal oscillation. Subsequent changes in lake sedimentation were associated with general warming and an unstable hydrological regime. An increase in humidification ∼8.2 ka BP was reflected by lake level rise and contributed to swamping of the watersheds. The aridest Holocene phase at ∼7.1–5.5 ka BP was reliably recorded by geochemical data, but poorly reflected in the stratigraphy of both profiles. Subsequent cooling and the resulting decrease in evaporation began at ∼5.5–4.9 ka BP. A pronounced cardinal shift in sedimentation conditions due to a gradual increase in precipitation was recorded at ∼4.9–2.8 ka BP, though short-term fluctuations towards dryness were also marked at ∼3.5–3.3 ka BP. The most significant increase in humidification and cooling began at 2.8 ka BP. Geochemical indices in the lacustrine sediments are climate sensitive and allowing us to obtain enough reliable data associated with changes in sedimentation environments. The stratigraphy of peat reflected the nuances of climatic changes less clearly and primarily demonstrated the stages of bog self-development; however, sphagnum peat provided a better-resolution record.

Water Management Planning for Swamp Buffalo in Sub-District Rambutan, Banyuasin Regency

The swamp is a water storage with a water resources contained, constantly or seasonally inundated, naturally formed in relatively flat or concave land with mineral or peat deposits, and overgrown with vegetation, which is an ecosystem [1]. Utilization of swamp land in Rambutan, Banyuasin district has not been optimal, in the study site has been a lot of research on buffalo that said the need for a water management system in the dry season. This study aims to analyze the water availability for buffalo, analyze the water requirements for buffaloes, plan the water management system for swamp buffalo of Rambutan Sub-District at South Sumatra, so during the dry season the water demands for feed and buffalo habitat are fulfilled as well. In this study water management planning scenarios for swamp buffalo cattle include: analyzing the minimum discharge for water availability, analyzing the water requirements for livestock and ponds, planning drainage ditches and ponds as water demands for swamp buffaloes. The lowest water level was at -0.508 MSL. With a river discharge of 14.64 m3 / sec, the highest water requirement occurred in July of 541,559.8 m3 and the lowest in August of 437714.3 m3, the channel can overcome the fulfillment of water buffalo at the location of research..

Comparative yield of some variety varieties on the background (Vaccinium L.) of introduction of mineral and microbial fertilizers at the performed peat deposits

Comparative yield of some variety varieties on the background (Vaccinium L.) of introduction of mineral and microbial fertilizers at the performed peat deposits

Holocene paleoecological changes and agro-pastoral impact on the La Narce du Béage mire (Massif Central, France)

A paleoecological study (macrofossils, pollen, cryptogam spores, non-pollen palynomorphs) was performed to investigate environmental changes recorded on the peat deposits of the La Narce du Béage mire (Massif Central, France). We reconstructed the development of a limnogenous mire ecosystem during the Holocene, consequently to the infilling of a small Late Glacial lake. Successions from aquatic flora ( Isoëtes, Nitella opaca/ syncarpa, Botryococcus, Alisma plantago-aquatica, Potamogeton, Sparganium) to mire plant species ( Alnus glutinosa, Betula nana, Betula pubescens, Cyperaceae, Ericaceae, Sphagnum) underlined a gradual eutrophication and acidification during the lowering of the water table. We demonstrated a clear link between these local hydro-ecological changes and the early Holocene climatic warming. Also dealing with archeology, we provided key issues for the identification of human-induced environmental changes. Three phases of ecological disturbances with clearings of the mixed-oak forest and agro-pastoral activities were evidenced at 7700–7300, 6800–6420, and 5500–4250 cal. BP. Our results confirmed early Neolithic (Cardial influences), middle Neolithic (Chassean), and late Neolithic (Ferrières group) frequentations of the Béage Plateau, probably included in large-scale socio-cultural changes (SE France, NW Mediterranean Basin). Later, forest clearings (beech and fir), cultivation, and pastoralism were outlined since the Iron Age (after 2300 cal. BP, that is, 350 BC). Increasing human pressure was especially recorded during the last 1700 years, with rye ( Secale cereale) cultivation and extensive livestock grazing around and on the mire, which is nowadays a protected ‘Natura 2000’ area.

Позднеголоценовая динамика растительного покрова и увлажнённости климата юго-восточного сектора Западно-Сибирской равнины по данным палинологического и ризоподного исследований торфяных отложений

Позднеголоценовая динамика растительного покрова и увлажнённости климата юго-восточного сектора Западно-Сибирской равнины по данным палинологического и ризоподного исследований торфяных отложений

Температурный режим торфяных олиготрофных почв лесостепи Западной Сибири (на примере Николаевского ряма)

Температурный режим торфяных олиготрофных почв лесостепи Западной Сибири (на примере Николаевского ряма)

A grain size and n-alkanes record of Holocene environmental evolution from a groundwater recharge lake in Badain Jaran Desert, Northwestern China

Vertical water transport plays an important role in the development and maintenance of lakes in arid zones. However, previous study of this phenomenon has focused mainly on the effects of regional precipitation, rather than effects of groundwater recharge, on arid-zone environmental change. We selected a sedimentary profile from a seasonal lake basin located in the hinterland of the Badain Jaran Desert, northwestern China, to assess the Holocene environmental evolution of this region and its response to climate change. Our results show that peat deposition from 11 to 10 ka indicates humidification after Younger Dryas (YD) event; the lake sediment and lower EM2 and lower principal component analysis (PCA)-1 scores indicate relative more humid environment from 10 to 7.8 ka; the lake sediment and higher EM2 and higher PCA-1 scores indicate most humid environment from 7.8 to 5.8 ka; the transition from lacustrine facies to limnetic facies and increasing salinity indicate drying trend from 5.8 to 2.5 ka; the aeolian sand sediment and lowest EM2 and lowest PCA-1 scores indicate driest environment from 2.5 to 0.8 ka; and lacustrine facies and finest grain size indicate relative humid environment during the ‘Little Ice Age’ period. The environment was relative humid in early Holocene, most Humid in mid-Holocene, and dry in mid-late Holocene. The moisture pattern in the hinterland of the Badain Jaran Desert was synchronous with that in the northeastern of Tibetan Plateau, which implies that the groundwater recharge lake was dominated by the intensity of groundwater recharge from monsoon margin area, especially the northeastern of Tibetan Plateau. As a record from groundwater recharge lake without runoff, our study provides the groundwater output quantity record from northeastern of Tibetan Plateau and would benefit the environment change research and regional water resources allocation around the Tibetan Plateau.