Siliceous microfossils in a Holocene, High Arctic peat deposit (Nordvestø, northwestern Greenland)

1994 ◽  
Vol 72 (2) ◽  
pp. 208-216 ◽  
Author(s):  
Kimberley M. Brown ◽  
Marianne S. V. Douglas ◽  
John P. Smol
Keyword(s):  
Environmental Variables ◽  
Testate Amoebae ◽  
High Arctic ◽  
Peat Deposit ◽  
Taxon Richness ◽  
Peat Deposits ◽  
Important Region ◽  
Geochemical Analyses ◽  
Microfossil Assemblage ◽  
Fine Tune

Siliceous microfossils (diatom valves, chrysophyte stomatocysts, and testate amoebae plates) were examined from a 2.6-m thick peat deposit from Nordvestø, northwestern Greenland (76°44′N, 73° 13′W). The moss, predominantly Aplodon wormskioldii (Hornem.) R.Br., began to accumulate approximately 6500 years ago and persisted for about 2000 years. Siliceous microfossils were generally well preserved in the peat, although taxon richness was low (i.e., only 19 diatom taxa, 16 chrysophyte cyst morphotypes, and 4 testate amoebae genera). Despite the paucity of taxa, marked shifts in species composition were recorded. Geochemical analyses and biogenic silica determination on the peat did not show any significant trends. To our knowledge, this study represents the first such combined analysis of a High Arctic peat, so our interpretations should be considered tentative. Environmental variables were not stable during the 2000 years of peat accumulation, as suggested by microfossil assemblage changes. For example, about 5000 years BP, diatoms reached their maximum relative abundance with taxa indicative of wetter habitats. We hypothesize that an influx of meltwater to the peat may have occurred at this time, perhaps because of wetter conditions or larger accumulations of snow during winter. These preliminary data indicate that siliceous microfossil analyses from arctic peat cores may eventually fine-tune paleoecological inferences for this climatically important region, once the environmental variables determining species distributions in peat deposits are determined. Key words: peat deposits, Greenland, diatoms, chrysophyte cysts, protozoan plates, paleoecology.

scholarly journals Characterization of peat deposit using ground penetrating radar: Survey experiments and data interpretation

2021 ◽  
Vol 928 (1) ◽  
pp. 012011
Author(s):  
A A Sinyutkina
Keyword(s):  
Accumulation Rate ◽  
Spatial Differentiation ◽  
Data Interpretation ◽  
Peat Deposit ◽  
Swamp Forest ◽  
Peat Accumulation ◽  
Raised Bogs ◽  
Peat Deposits ◽  
Zone Of Influence ◽  
Ground Penetrating

Abstract The paper deals with the possibilities of different wave frequency antennae applications for estimation of the depth of peat deposits and detection of peat layers with different physical characteristics. We employed a GPR system “OKO-2” (“Logical systems”, Russia) with 250 MHz, 700 MHz, and 1700 MHz shielded antennae. The surveys were conducted in 2017–2019 within the pristine and drained raised bogs and swamp forest in the south taiga subzone of Western Siberia to assess the spatial differentiation of the peat deposit and the modern peat accumulation rate within drained bogs. The peculiarities of field surveying, GPR data processing and interpretation are shown. Based on GPR data analysis the influence zone of Bakchar bog and modern peat accumulation within drained bogs were assessed. We noted that the Bakchar bog has a vast zone of influence reaching 700 m from the bog border where peat accumulation is observed. The modern peat accumulation is observed within Bakchar the bog. Drained sites of Ust-Bakchar bog are characterised by the absent peat accumulation or degradation of the peat deposits.

scholarly journals The Flooded Peat Deposit Characteristic and Assessment of its Impact upon Water Quality in the Boguchansk Reservoir

2012 ◽  
pp. 80-90
Author(s):  
Keyword(s):  
Water Quality ◽  
Organic Matter ◽  
Chemical Properties ◽  
Peat Deposit ◽  
Physical Chemical ◽  
Peat Deposits

Assessment of the flooded peat deposit in the Boguchansk Reservoir floor impact on the water quality has been performed. Characteristic of the flooded bogs and peat deposits has been given; their physical/chemical properties have been described. Reserves of organic matter, nitrogen and microelements in the peat deposit forecasted for floating have been calculated, their influence on water quality in the reservoir to be designed has been considered. A conclusion on the necessity of monitoring of the flooded in the process of the reservoir exploiting hydromorphic ecosystems has been made.

scholarly journals Assessment of applying VLF geophysical method to determine the peat deposit thickness

2020 ◽  
Vol 5 (3) ◽  
pp. 224-234
Author(s):  
T. B. Yakonovskaya ◽  
A. I. Zhigulskaya ◽  
P. A. Yakonovsky
Keyword(s):  
Global Climate ◽  
Wetland Management ◽  
Low Frequency ◽  
Data Interpretation ◽  
Peat Deposit ◽  
Geophysical Method ◽  
Commercial Activity ◽  
Peat Deposits ◽  
Natural Density ◽  
High Degree

Peat deposits accumulate large reserves of carbon and play an important role in formation of global climate, biosphere, and hydrological conditions. High degree of knowledge of peat reserves is one of the prerequisites for scientifically based and economically viable wetland management. For economically efficient commercial activity, an enterprise developing a peat deposit must be confident in the availability of sufficient and high quality commercial peat reserves. Therefore, the topic of studying the thickness of peat deposits is quite relevant. The paper analyzes the experience of using the geophysical method called VLF ("very low frequency") to study the thickness of peat deposits. The method consisted of using a VLF receiver to measure the properties of VLF emitted by the peat deposit and the underlying mineral ground. The study was carried out at the Beloe Lake peat deposit in the Tukayevsky district of Tatarstan, at three peat areas of different depths: deep-lying (over 3 m), intermediate (1.5 – 3 m), and shallow (up to 1.5 m). The depth was confirmed by direct measurements in the wells. Low-frequency (VLF) measurements were carried out along the geophysical paths at each area of the peat deposit. The data were processed using the NAMEMD (Noise Empirical Decomposition) method and converted to resistivity and depth values using the specialized software. The study showed that the resistivity differs significantly between the areas of deep-lying and shallow peat. The resistivity varies depending on the peat thickness and the thickness of the buried wood horizons. In the horizons of deep-lying peat, the resistivity is strongly influenced by the degree of peat decomposition, its natural density and moisture. The presence of peaks and their height on the data interpretation plots characterizes the number and thickness of the horizons of buried wood in the peat deposit. With increasing depth of peat occurrence, the resistivity increases significantly. However, in the shallow areas, it does not show differences, being characteristic for the deep-lying peat area. This proves that the VLF method works correctly in peat layers and is capable to indicate the peat thickness, the number and thickness of the buried wood horizons.

scholarly journals Investigating peat deposits with ground-penetrating radar – a case study of drained bogs in Western Siberia, Russia

2021 ◽  
Vol 258 ◽  
pp. 12007
Author(s):  
Anna Sinyutkina
Keyword(s):  
Ground Penetrating Radar ◽  
Spatial Differentiation ◽  
Displacement Sensor ◽  
Peat Deposit ◽  
Taiga Zone ◽  
Peat Accumulation ◽  
Raised Bogs ◽  
Peat Deposits ◽  
Key Sites ◽  
Ground Penetrating

This paper deals with the assessment of the peat deposit transformation of two drained raised bogs (the Bakchar bog drained for forestry and the Ust-Bakchar bog drained for peat extraction) within the Western Siberian taiga zone. Specifically, the objectives of this study were to: 1) characterise the peat deposits of key sites with the use of ground-penetrating radar (GPR) and manual data; 2) estimate the spatial differentiation of modern peat accumulation rates at the microhabitat level. We used the GPR system “OKO-2” with 250, 700, and 1700 MHz shielded antennas and a displacement sensor. We concluded that the use of this GPR complex allowed the assessment of the total depth of the peat deposit, the depth of the fibric peat layer, and the thickness of the layer formed after drainage. We paid attention to defining the patterns of layers formed at depth after drainage within hummocks or hollow microhabitats. The peat accumulation after drainage was not continual throughout all mire surface, which was most typical for plots of the Ust-Bakchar bog. The modern peat accumulation increased 1.3–2.2 times from hollows to hummocks and it was 2–4 times higher within the Bakchar bog than in the Ust-Bakchar bog.

scholarly journals Petrography, Palynology, and Organic Geochemistry of Neogene Paralic Coal, Mukah,Sarawak, Malaysia: Implications For Paleomires, and Peat-Forming Conditions

2021 ◽  
Author(s):  
Nor Syazwani Zainal Abidin ◽  
Khairul Azlan Mustapha ◽  
Wan Hasiah Abdullah ◽  
Zainey Konjing
Keyword(s):  
Organic Geochemistry ◽  
Coal Seams ◽  
Lowland Forest ◽  
Sequence Stratigraphic ◽  
Peat Deposits ◽  
Biomass Loss ◽  
The Rich ◽  
Wet Climate ◽  
Geochemical Analyses ◽  
Water Saturated

Abstract The eight coal seams of Neogene paralic coals from Mukah coalfield, Sarawak, Malaysia, were investigated using petrographical, palynological, and organic geochemical analyses to describe coal-forming vegetation, conditions during peat development and precursor mires, and their associations in a sequence-stratigraphic context. The petrographic data of the coals implies the existence of oxygen-deficient and water-saturated conditions in the precursor mires. The condition of low mire oxidation was followed by biomass loss from the mires. The Mukah coals are suggested to be deposited in freshwater peat swamps, and the rich preservation of angiosperm pollens indicates that the organic matter in dense and lowland forest vegetation was mostly terrigenous. The overwhelming presence of Casuarina and Calamus types, suggesting the paleomires were closely linked to Kerapah/Kerangas peat forest and marginally bordered by rattan and supported by the biomarker data. Rheotrophic–ombrotrophic mires were temporarily formed because of water table fluctuations, which strongly depend on ever-wet climate changes and syn-depositional tectonic during the Neogene, resulting in balanced to high peat accumulation and preservation. A maximum thickness of 35m of peat deposits that formed between 10,000 and 175,000 years ago is suggested. The coals are proposed to be influenced by transgressive to initial highstand cycles within the paralic setting.

Comparison of bog phytocenosis ecotopes parameters and peat deposit depths of the Beloe bog (Perm region, Russia)

2021 ◽  
Vol 7 (1) ◽  
pp. 48-64
Author(s):  
I.F. Abdulmanova ◽  
◽  
E.A. Igosheva ◽  
Keyword(s):  
Peat Deposit ◽  
Ecological Scales ◽  
Peat Deposits ◽  
Perm Krai ◽  
Ecological Parameters ◽  
Time Required ◽  
Relationship Of ◽  
The Relationship ◽  
Group Species

It is known that phytoindication of the nature and depth of peat deposits is possible only when, among other factors, the geographical and geomorphological position of the bog systems is taken into account. The aim of this study is to determine whether or not there is a relationship between peat deposit thickness, phytocenosis composition and ecological parameters of plant habitats, using the example of the Beloe Bog located in the Sylvensko-Irenskaya lowland in the south-east of Perm Krai. Measure ments of the depth of the peat deposit were carried out using a peat probe, followed by the determination of the volumes of the peat bog in the GIS (ArcGIS (ESRI)). The diversity of peatland plant com-munities is described, their ecological-cenotic analysis and phytoindication analysis of ecotopes is carried out using Ellenberg and Landolt ecological scales using EcoScaleWin software. The results allow to update the stock data of geological exploration 1969. Ecological-cenotic and phytoindication analyzes revealed differences between pine-dwarf shrub-sphagnum and birch-menyanthes-sphagnum communities. A Spearman correlation coefficient demonstrated a relationship between peat deposit depths and the proportion of Water-Swamp ecological-cenotic group species in the communities, as well as with a number of ecological parameters of the ecotopes. The use of two different ecological scales revealed inconsistency between them. The article substantiates the chosen spatial tactics for measuring the peatland depth of a small irregularly shaped bog and also calculates the time required to measure the thickness of a conven-tional peat deposit of 1000 hectares. The relationship of this work to ongoing palaeoecological research in Perm Krai is highlighted. A comparison is made between the available data on the Beloe Bog and the results of phytoindication studies of the peatland thickness of Western Siberia known to the authors. The limitations and prospects of a series of similar studies in Perm Krai, which will reveal regional and zonal patterns in the spatial structure of bog communities and their relation to the thickness of peat deposits, are considered.

The mesostigmatid mite (Acari: Parasitiformes) fauna of Svalbard: a revised inventory of a high Arctic archipelago

Zootaxa ◽  
2011 ◽  
Vol 3091 (1) ◽  
pp. 33 ◽  
Author(s):  
MARÍA LUISA ÁVILA-JIMÉNEZ ◽  
DARIUSZ J. GWIAZDOWICZ ◽  
STEPHEN JAMES COULSON
Keyword(s):  
Current Knowledge ◽  
High Arctic ◽  
Invertebrate Fauna ◽  
Svalbard Archipelago ◽  
Species Ranges ◽  
Fresh Material ◽  
Important Region ◽  
Island Group ◽  
Slide Material

The need for comprehensive studies of the invertebrate fauna in the high Arctic is increasingly acknowledged in order to more fully understand ecosystem functioning, resilience and to project future changes in the biodiversity and species ranges. Information on the mesostigmatid fauna in the high Arctic is scarce and scattered. Large regions of the high Arctic archipelago of Svalbard, including most of the areas in the east of the island group, have never been surveyed for the mesostigmatid fauna. Furthermore, most of the current knowledge on the mesostigmatid fauna of this important region in the European high Arctic originates from studies in the early 20 th century. Much of the associated slide material no longer exists, either being mislaid or deliberately destroyed, resulting in an ambiguous and potentially misleading mesostigmatid fauna checklist in which identifications and potential synonyms cannot be reliably assessed. Determination of fresh material sampled between 2007–2010 may be an ideal procedure to resolve the great number of uncertainties about the mesostigmatid fauna of the Svalbard archipelago. Twelve out of the 27 species recorded from the Svalbard archipelago were found in the new samples collected from a large number of localities and microhabitats. No new species were identified in the current campaign, and most of the non-observed species are considered to be past missidentifications or potential synonyms. Combining this study with recent publications provides a total mesostigmatid mite diversity for Svalbard of 22 species. This represents the most accurate checklist of the mesostigmatid mite fauna of the archipelago to date.

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