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Sample records for bogs

  1. Bog bodies

    DEFF Research Database (Denmark)

    Lynnerup, Niels

    2015-01-01

    In northern Europe during the Iron Age, many corpses were deposited in bogs. The cold, wet and anaerobic environment leads in many cases to the preservation of soft tissues, so that the bodies, when found and excavated several thousand years later, are remarkably intact. Since the 19th century...... the bog bodies have been studied using medical and natural scientific methods, and recently many bog bodies have been re-examined using especially modern, medical imaging techniques. Because of the preservation of soft tissue, especially the skin, it has been possible to determine lesions and trauma....... Conversely, the preservation of bones is less good, as the mineral component has been leached out by the acidic bog. Together with water-logging of collagenous tissue, this means that if the bog body is simply left to dry out when found, as was the case pre-19th century, the bones may literally warp...

  2. The changing landscape of Clara Bog: the history of an Irish raised bog

    NARCIS (Netherlands)

    Crushell, P.H.; Connolly, A.; Schouten, M.G.C.; Mitchell, F.J.G.

    2008-01-01

    Clara Bog is one of the few raised bogs that has not been fully exploited in the Irish midlands and is a reminder of how the landscape of this region once appeared. This paper describes how the Clara Bog landscape has been changing since the commencement of the Holocene 11,500 years ago. Initially

  3. Restoration of pitcher plant bogs in eastern Texas, USA

    Science.gov (United States)

    Ronald Mize; Robert E. Evans; Barbara R. MacRoberts; Michael H. MacRoberts; D. Craig Rudolph

    2005-01-01

    Pitcher plant bogs, also referred to as hillside seepages bogs or hillside bogs, are extremely restricted on the West Gulf Coastal Plain. the number and extent of extant bogs is in the low hundreds, comprising no more than a few thousand hectares of habitat. These bogs support a large number of plant species of significant conservation concern. threats to existing bogs...

  4. "Den lille havfrue" som digital pop op-bog

    DEFF Research Database (Denmark)

    Mygind, Sarah

    2017-01-01

    Anmeldelse af: DIGITAL POP OP-BOG H. C. ANDERSEN OG BOOKS & MAGIC DEN LILLE HAVFRUE Bog og App til iOS & Android 5......Anmeldelse af: DIGITAL POP OP-BOG H. C. ANDERSEN OG BOOKS & MAGIC DEN LILLE HAVFRUE Bog og App til iOS & Android 5...

  5. Establishing Sphagnum cultures on bog grassland, cut-over bogs, and floating mats: procedures, costs and area potential in Germany

    Directory of Open Access Journals (Sweden)

    S. Wichmann

    2017-04-01

    Full Text Available Sphagnum biomass is valued as a high-quality constituent of horticultural growing media. The cultivation of Sphagnum (peatmoss was tested successfully on peat soil and on artificial mats floating on acidic water bodies. But whether Sphagnum farming is economically feasible is unclear. Drawing on experience gained during four research projects in Germany we compared the procedures, costs and area potential for establishing large-scale Sphagnum cultures. Establishment costs were clearly lower for soil-based cultivation (€8.35 m-2 to €12.80 m 2 than for water-based cultivation (€17.34 m-2 to €21.43 m-2. Relating costs to the predicted dry mass yield over the total cultivation time resulted in values of €1,723 t-1 on cut-over bog, €2,646 t-1 on former bog grassland, €9,625 t -1 on floating mats without pre-cultivation and €11,833 t-1 on pre-cultivated Sphagnum mats. The high production costs of the mats (without pre-cultivation 54 % and with pre-cultivation 63 % of total costs resulted in the highest overall costs. In the case of soil-based Sphagnum cultures, the costs of purchasing Sphagnum diaspores were most influential (on bog grassland 46 % and on cut-over bog 71 % of total costs. The lowest costs relate to cut-over bog because of the smaller effort required for site preparation compared to taking off the topsoil of former bog grassland and the limited costs for the assumed irrigation system. In the case of former bog grassland, the high investment costs for the project-specific automatic water management boosted the establishment costs. Taking into account potential savings on the irrigation system and the high area potential, bog grassland emerges as the most promising land category for Sphagnum farming in Germany.

  6. Radioactive fallout nuclides in a peat-bog ecosystem

    International Nuclear Information System (INIS)

    Pausch, G.; Hofmann, W.; Steger, F.; Tuerk, R.

    1996-01-01

    The Province of Salzburg belongs to the regions with the highest contamination from the Chernobyl-fallout outside the former USSR. The peat-bog investigated in this study is situated in Koppl, east of Salzburg. A peat-bog is a special example of an ecosystem, which is generally not disturbed by human activities because it is under strict nature-conservation and whose soil structure is not affected by animal activities from moles and earthworms. Peat-bogs are characterized by acidic soils which are high in organic material and low in clay mineral content. A number of previous studies have demonstrated that especially in peat-bogs and especially in the Koppl-peat-bog very high amounts of radioactive fallout nuclides from the Chernobyl accident and from the bomb-testings could be found

  7. Geoinformatics meets education for a peat bog information system

    Science.gov (United States)

    Michel, Ulrich; Fiene, Christina; Plass, Christian

    2010-10-01

    Within the project "Expedition Bog: Young researchers are experimenting, exploring and discovering" a bog-information- system is developed by the Department of Geography (University of Education Heidelberg, Germany), the Institute for Geoinformatics and Remote Sensing (University of Osnabrueck, Germany; the NABU Umweltpyramide gGmbH. This information system will be available for schools and to the public. It is supplemented by teaching units on various topics around the bog via an online platform. The focus of the project, however, is the original encounter with the bog habitat. This is realized by a GPS scavenger hunt with small research tasks and observations, mapping and experiments. The project areas are the Huvenhoops bog and the Lauenbruecker bog in Rotenburg in Lower Saxony, Germany. Equipped with a researcher backpack, GPS device and a mobile bog book by means of a pocket PC, students can discover different learning stations in the project bogs. In our areas the students can learn more about different topics such as "the historical memory of the bog", "water", "peat moss and other plants" and "animals of the bog". Moreover small inquiry research projects can be executed. Experimenting on site helps students to develop important scientific findings and increases their curiosity and enthusiasm for nature. It also promotes a number of other basic skills such as literacy, language skills, social skills or fine motor skills. Moreover it also fosters the development of a positive attitude to science in general. The main objective of the project is to promote sustainable environmental education, as well as the development of environmental awareness. This will be accomplished through the imparting of knowledge but also through experiencing nature with all senses in the context of original encounters.

  8. Iron from Zealandic bog iron ore -

    DEFF Research Database (Denmark)

    Lyngstrøm, Henriette Syrach

    2011-01-01

    og geologiske materiale, metallurgiske analyser og eksperimentel arkæologiske forsøg - konturerne af en jernproduktion med udgangspunkt i den sjællandske myremalm. The frequent application by archaeologists of Werner Christensen’s distribution map for the occurrence of bog iron ore in Denmark (1966...... are sketched of iron production based on bog iron ore from Zealand....

  9. Field Simulation of Global Change: Transplanting Northern Bog Mesocosms Southward

    NARCIS (Netherlands)

    Breeuwer, A.J.G.; Heijmans, M.M.P.D.; Robroek, B.J.M.; Berendse, F.

    2010-01-01

    A large proportion of northern peatlands consists of Sphagnum-dominated ombrotrophic bogs. In these bogs, peat mosses (Sphagnum) and vascular plants occur in an apparent stable equilibrium, thereby sustaining the carbon sink function of the bog ecosystem. How global warming and increased nitrogen

  10. [Methanotrophic bacteria of acid sphagnum bogs].

    Science.gov (United States)

    Dedysh, S N

    2002-01-01

    Acid sphagnum bogs cover a considerable part of the territory of Russia and are an important natural source of biogenic methane, which is formed in their anaerobic layers. A considerable portion of this methane is consumed in the aerobic part of the bog profile by acidophilic methanotrophic bacteria, which comprise the methane filter of sphagnum bogs and decrease CH4 emission to the atmosphere. For a long time, these bacteria escaped isolation, which became possible only after the elucidation of the optimal conditions of their functioning in situ: pH 4.5 to 5.5; temperature, from 15 to 20 degrees C; and low salt concentration in the solution. Reproduction of these conditions and rejection of earlier used media with a high content of biogenic elements allowed methanotrophic bacteria of two new genera and species--Methylocella palustris and Methylocapsa acidophila--to be isolated from the peat of sphagnum bogs of the northern part of European Russia and West Siberia. These bacteria are well adapted to the conditions in cold, acid, oligotrophic sphagnum bogs. They grow in a pH range of 4.2-7.5 with an optimum at 5.0-5.5, prefer moderate temperatures (15-25 degrees C) and media with a low content of mineral salts (200-500 mg/l), and are capable of active nitrogen fixation. Design of fluorescently labeled 16S rRNA-targeted oligonucleotide probes for the detection of Methylocella palustris and Methylocapsa acidophila and their application to the analysis of sphagnum peat samples showed that these bacteria represent dominant populations of methanotrophs with a density of 10(5)-10(6) cells/g peat. In addition to Methylocella and Methylocapsa populations, one more abundant population of methanotrophs was revealed (10(6) cells/g peat), which were phylogenetically close to the genus Methylocystis.

  11. 137Cs in a raised bog in central Sweden

    International Nuclear Information System (INIS)

    Rosen, K.; Vinichuk, M.; Johanson, K.J.

    2009-01-01

    The vertical distribution of 137 Cs activity in peat soil profiles and 137 Cs activity concentration in plants of various species was studied in samples collected at two sites on a raised bog in central Sweden. One site (open bog) was in an area with no trees and only a few sparsely growing plant species, while the other (low pine) was less than 100 m from the open bog site and had slowly growing Scots pine, a field layer dominated by some ericaceous plants and ground well-covered by plants. The plant samples were collected in 2004-2007 and were compared with samples collected in 1989 from the same open bog and low pine sites. Ground deposition of 137 Cs in 2005 was similar at both sites, 23 000 Bq m -2 . In the open bog peat profile it seems to be an upward transport of caesium since a clear peak of 137 Cs activity was found in the uppermost 1-4 cm of Sphagnum layers, whereas at the low pine site 137 Cs was mainly found in deeper (10-12 cm) layers. The migration rate was 0.57 cm yr -1 at the open bog site and the migration centre of 137 Cs was at a depth of 10.7, while the rate at the low pine site was 0.78 cm yr -1 and the migration centre was at 14.9 cm. Heather (Calluna vulgaris) was the plant species with the highest 137 Cs activity concentrations at both sites, 43.5 k Bq -1 DM in 1989 decreasing to 20.4 in 2004-2007 on open bog and 22.3 k Bq kg -1 DM in 1989 decreasing to 11.2 k Bq -1 DM by the period 2004-2007 on the low pine site. 137 Cs transfer factors in plants varied between 0.88 and 1.35 on the open bog and between 0.48 and 0.69 m 2 kg -1 DM at the low pine site.

  12. RAISED BOGS ON THE NORTH-EAST OF EUROPE

    Directory of Open Access Journals (Sweden)

    T. K. YURKOVSKAYA

    2004-01-01

    Full Text Available In the Northeastern Europe 2 types of raised bogs are distinguished: coastal (Southern White Sea raised hogs and continental (Pechora-Onega raised bogs. They have been compared as to their flora, prevailing syntaxa, characteristics of their complexes, structure of mire massifs and composition of peat deposits.

  13. Revival of Dutch Sphagnum bogs: a reasonable perspective?

    NARCIS (Netherlands)

    Tomassen, H.B.M.

    2004-01-01

    In the Netherlands, the area of raised bogs has been virtually lost during two millennia of human impact. Much effort has been invested in rewetting these cut-over bogs, but the recovery of Sphagnum-dominated vegetation often failed. The work presented includes research on the role of hydrochemistry

  14. Communities of larger fungi of ombrotrophic bogs in West Siberia

    Directory of Open Access Journals (Sweden)

    N.V. Filippova

    2014-11-01

    Full Text Available Bogs are common ecosystems in the Taiga of West Siberia. Little is known about mycological diversity in these important ecosystems. This article summarises the results of a two-year study of the macrofungi in two bogs near the town of Khanty-Mansiysk. Sporocarps were collected in 20 plots (about 300 m2 established in Mukhrino Bog as well as during random walks in Mukhrino Bog and Chistoe Bog in the late summer–autumn of 2012 and 2013. The plots were established in two common bog habitats representing the Ledo-Sphagnetum fusci (LS and Scheuchzerio palustris-Sphagnetum cuspidati (SS plant community associations. A total of 59 distinct fungal taxa were collected from the two bogs, with the LS association having a higher species richness and diversity than the SS association (50 taxa vs. 16 taxa and 30–40 taxa per 1000 m2 vs. 6–10 taxa per 1000 m2, respectively. Each of the two plant community associations has its own characteristic fungal taxa, with the LS association having 13 characteristic taxa and the SS association having five. Nearly two thirds of the fungal taxa are saprotrophic, mainly of Sphagnum spp., while others are mycorrhizal, mainly with Pinus spp. Most taxa were collected fewer than ten times during the study period and, hence, are considered rare and may need to be recognised for conservation programmes in this region.

  15. Modeling of the carbon dioxide fluxes in European Russia peat bogs

    Energy Technology Data Exchange (ETDEWEB)

    Kurbatova, J; Tatarinov, F; Varlagin, A; Shalukhina, N; Olchev, A [A N Severtsov Institute of Ecology and Evolution of RAS, Leninsky Prospekt 33, Moscow 119071 (Russian Federation); Li, C, E-mail: kurbatova.j@gmail.co [Institute for the Study of Earth, Oceans and Space, University of New Hampshire, Durham, NH 03824 (United States)

    2009-10-15

    A process-based model (Forest-DNDC) was applied to describe the possible impacts of climate change on carbon dioxide (CO{sub 2}) fluxes from a peat bog in European Russia. In the first step, Forest-DNDC was tested against CO{sub 2} fluxes measured by the eddy covariance method on an oligotrophic bog in a representative region of the southern taiga (56 deg. N 33 deg. E). The results of model validations show that Forest-DNDC is capable of quantifying the CO{sub 2} fluxes from the bog ecosystem. In the second step, the validated model was used to estimate how the expected future changes of the air temperature and water table depth could affect the C dynamics in the bogs. It was shown that a decrease in the water table and an increase in temperature influence significantly the CO{sub 2} exchange between our bog ecosystem and the atmosphere. Under elevated temperature and deepened water table the bog ecosystems could become a significant source of atmospheric CO{sub 2}.

  16. Synanthropization of the Baltic-type raised bog “Roby” (NW Poland

    Directory of Open Access Journals (Sweden)

    Sotek Zofia

    2015-06-01

    Full Text Available Raised and transitional peat bogs, despite their considerable resistance to synanthropization, as a result of anthropogenic transformations are exposed to the colonisation by alien species. One of them is the peatland “Roby”, where, in the years 2007-2009 and 2014, floristic, phytosociological and soil studies were carried out in order to record the signs of ongoing synanthropization. Conducted observations and analyses indicated that the expansion of willows has taken place and at present they occupy a large part of the bog, encroaching into bog birch forest and successfully competing with Myrica gale. Progressive peat mineralisation and constructed surfaced roads within the bog, contributed to the appearance and wide distribution of synanthropic species, such as: Urtica dioica, Impatiens parviflora and Spiraea salicifolia. Raised bog communities and their characteristic species occur on a few fragments of the bog, in north-western part, where water regime is shaped mainly by precipitation and peat deposit is fairly well-preserved. At the same time, in the patches of these communities, a distinct unfavourable increase in the share of Molinia caerulea is observed.

  17. Radionuclides in peat bogs and energy peat

    International Nuclear Information System (INIS)

    Helariutta, K.; Rantavaara, A.; Lehtovaara, J.

    2000-06-01

    The study was aimed at improving the general view on radionuclides contents in energy peat produced in Finland. The annual harvest of fuel peat in 1994 was studied extensively. Also thirteen peat bogs used for peat production and one bog in natural condition were analysed for vertical distributions of several radionuclides. These distributions demonstrate the future change in radioactivity of energy peat. Both natural nuclides emitting gamma radiation ( 238 U, 235 U, 232 Th, 226 Ra, 40 K) and radiocaesium ( 137 Cs, 134 Cs) origin in fallout from a nuclear power plant accident (1986) and in atmospheric nuclear weapon tests were analysed. The beta and alpha active natural nuclides of lead and polonium ( 210 Pb, 210 Po) were determined on a set of peat samples. These nuclides potentially contribute to radiation exposure through inhalation when partially released to atmosphere during combustion of peat. The activity concentrations of natural radionuclides often increased towards the deepest peat bog layers whereas the radioactive caesium deposited from atmosphere was missing in the deep layers. In undisturbed surface layers of a natural bog and peat production bogs the contents of 210 Pb and 210 Po exceeded those of the deeper peat layers. The nuclides of the uranium series in the samples were generally not in radioactive equilibrium, as different environmental processes change their activity ratios in peat. Radiation exposure from handling and utilisation of peat ash was estimated with activity indices derived from the data for energy peat harvested in 1994. Intervention doses were exceeded in a minor selection of samples due to 137 Cs, whereas natural radionuclides contributed very little to the doses. (orig.)

  18. Rain increases methane production and methane oxidation in a boreal thermokarst bog

    Science.gov (United States)

    Neumann, R. B.; Moorberg, C.; Turner, J.; Wong, A.; Waldrop, M. P.; Euskirchen, E. S.; Edgar, C.; Turetsky, M. R.

    2017-12-01

    Bottom-up biogeochemical models of wetland methane emissions simulate the response of methane production, oxidation and transport to wetland conditions and environmental forcings. One reason for mismatches between bottom-up and top-down estimates of emissions is incomplete knowledge of factors and processes that control microbial rates and methane transport. To advance mechanistic understanding of wetland methane emissions, we conducted a multi-year field investigation and plant manipulation experiment in a thermokarst bog located near Fairbanks, Alaska. The edge of the bog is experiencing active permafrost thaw, while the center of the bog thawed 50 to 100 years ago. Our study, which captured both an average year and two of the wettest years on record, revealed how rain interacts with vascular vegetation and recently thawed permafrost to affect methane emissions. In the floating bog, rain water warmed and oxygenated the subsurface, but did not alter soil saturation. The warmer peat temperatures increased both microbial methane production and plant productivity at the edge of the bog near the actively thawing margin, but minimally altered microbial and plant activity in the center of the bog. These responses indicate processes at the edge of the bog were temperature limited while those in the center were not. The compounding effect of increased microbial activity and plant productivity at the edge of the bog doubled methane emissions from treatments with vascular vegetation during rainy years. In contrast, methane emissions from vegetated treatments in the center of the bog did not change with rain. The oxygenating influence of rain facilitated greater methane oxidation in treatments without vascular vegetation, which offset warming-induced increases in methane production at the edge of the bog and decreased methane emissions in the center of the bog. These results elucidate the complex and spatially variable response of methane production and oxidation in

  19. Prospects for Sphagnum bogs subject to high nitrogen deposition

    NARCIS (Netherlands)

    Limpens, J.

    2003-01-01

    S phagnum bogs harbour a wealth of rare vascular plant and bryophyte species, preserve an amazing pollen record and are long-term sinks for atmospheric carbon. Unfortunately, the relatively low production and decomposition rates, that make these bogs such important environments,

  20. Carbon dioxide emission from raised bog surface after peat extraction

    Directory of Open Access Journals (Sweden)

    Turbiak Janusz

    2017-12-01

    Full Text Available Research on CO2 emission from a raised bog after completion of peat extraction was performed in 2011–2013. CO2 emissions were determined by the chamber method. Twenty years after the termination of peat extraction, the bog surface was almost entirely devoid of plants. CO2 emission from the bog varied depending on temperature and water conditions and was 418 mg·m−2·h−1 on average during the research period. CO2 losses on the raised bog were on average 19.7 Mg·ha−1·year−1 during the research period which corresponded to a carbon loss of 5.37 Mg·ha−1·year−1 or mineralisation of 9.6 Mg·ha−1·year−1 of organic mass of 56% carbon content. It is possible to reduce organic mass losses and CO2 emission to the atmosphere from the bog surface after peat extraction has been terminated by reconstruction of initial water conditions, i.e. retaining a high ground water level and restoration of aquatic plant communities.

  1. Microform-related community patterns of methane-cycling microbes in boreal Sphagnum bogs are site specific.

    Science.gov (United States)

    Juottonen, Heli; Kotiaho, Mirkka; Robinson, Devin; Merilä, Päivi; Fritze, Hannu; Tuittila, Eeva-Stiina

    2015-09-01

    Vegetation and water table are important regulators of methane emission in peatlands. Microform variation encompasses these factors in small-scale topographic gradients of dry hummocks, intermediate lawns and wet hollows. We examined methane production and oxidization among microforms in four boreal bogs that showed more variation of vegetation within a bog with microform than between the bogs. Potential methane production was low and differed among bogs but not consistently with microform. Methane oxidation followed water table position with microform, showing higher rates closer to surface in lawns and hollows than in hummocks. Methanogen community, analysed by mcrA terminal restriction fragment length polymorphism and dominated by Methanoregulaceae or 'Methanoflorentaceae', varied strongly with bog. The extent of microform-related variation of methanogens depended on the bog. Methanotrophs identified as Methylocystis spp. in pmoA denaturing gradient gel electrophoresis similarly showed effect of bog, and microform patterns were stronger within individual bogs. Our results suggest that methane-cycling microbes in boreal Sphagnum bogs with seemingly uniform environmental conditions may show strong site-dependent variation. The bog-intrinsic factor may be related to carbon availability but contrary to expectations appears to be unrelated to current surface vegetation, calling attention to the origin of carbon substrates for microbes in bogs. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  2. {sup 137}Cs in a raised bog in central Sweden

    Energy Technology Data Exchange (ETDEWEB)

    Rosen, K. [Department of Soil and Environment, Swedish University of Agricultural Sciences, SLU, Ulls vag 17, Box 7014, SE-75007, Uppsala (Sweden)], E-mail: klas.rosen@mv.slu.se; Vinichuk, M. [Department of Soil and Environment, Swedish University of Agricultural Sciences, SLU, Ulls vag 17, Box 7014, SE-75007, Uppsala (Sweden); Department of Ecology, Zhytomyr State Technological University, 103 Cherniakhovsky Str., 10005 Zhytomyr (Ukraine); Johanson, K.J. [Department of Soil and Environment, Swedish University of Agricultural Sciences, SLU, Ulls vag 17, Box 7014, SE-75007, Uppsala (Sweden)

    2009-07-15

    The vertical distribution of {sup 137}Cs activity in peat soil profiles and {sup 137}Cs activity concentration in plants of various species was studied in samples collected at two sites on a raised bog in central Sweden. One site (open bog) was in an area with no trees and only a few sparsely growing plant species, while the other (low pine) was less than 100 m from the open bog site and had slowly growing Scots pine, a field layer dominated by some ericaceous plants and ground well-covered by plants. The plant samples were collected in 2004-2007 and were compared with samples collected in 1989 from the same open bog and low pine sites. Ground deposition of {sup 137}Cs in 2005 was similar at both sites, 23 000 Bq m{sup -2}. In the open bog peat profile it seems to be an upward transport of caesium since a clear peak of {sup 137}Cs activity was found in the uppermost 1-4 cm of Sphagnum layers, whereas at the low pine site {sup 137}Cs was mainly found in deeper (10-12 cm) layers. The migration rate was 0.57 cm yr{sup -1} at the open bog site and the migration centre of {sup 137}Cs was at a depth of 10.7, while the rate at the low pine site was 0.78 cm yr{sup -1} and the migration centre was at 14.9 cm. Heather (Calluna vulgaris) was the plant species with the highest {sup 137}Cs activity concentrations at both sites, 43.5 k Bq{sup -1} DM in 1989 decreasing to 20.4 in 2004-2007 on open bog and 22.3 k Bq kg{sup -1} DM in 1989 decreasing to 11.2 k Bq{sup -1} DM by the period 2004-2007 on the low pine site. {sup 137}Cs transfer factors in plants varied between 0.88 and 1.35 on the open bog and between 0.48 and 0.69 m{sup 2} kg{sup -1} DM at the low pine site.

  3. Exploring climatic controls on blanket bog litter decomposition across an altitudinal gradient

    Science.gov (United States)

    Bell, Michael; Ritson, Jonathan P.; Clark, Joanna M.; Verhoef, Anne; Brazier, Richard E.

    2016-04-01

    The hydrological and ecological functioning of blanket bogs is strongly coupled, involving multiple ecohydrological feedbacks which can affect carbon cycling. Cool and wet conditions inhibit decomposition, and favour the growth of Sphagnum mosses which produce highly recalcitrant litter. A small but persistent imbalance between production and decomposition has led to blanket bogs in the UK accumulating large amounts of carbon. Additionally, healthy bogs provide a suite of other ecosystems services including water regulation and drinking water provision. However, there is concern that climate change could increase rates of litter decomposition and disrupt this carbon sink. Furthermore, it has been argued that the response of these ecosystems in the warmer south west and west of the UK may provide an early analogue for later changes in the more extensive northern peatlands. In order to investigate the effects of climate change on blanket bog litter decomposition, we set-up a litter bag experiment across an altitudinal gradient spanning 200 m of elevation (including a transition from moorland to healthy blanket bog) on Dartmoor, an area of hitherto unstudied, climatically marginal blanket bog in the south west of the UK. At seven sites, water table depth and soil and surface temperature were recorded continuously. Litter bags filled with the litter of three vegetation species dominant on Dartmoor were incubated just below the bog surface and retrieved over a period of 12 months. We found significant differences in the rate of decomposition between species. At all sites, decomposition progressed in the order Calluna vulgaris (dwarf shrub) > Molinia caerulea (graminoid) > Sphagnum (bryophyte). However, while soil temperature did decrease along the altitudinal gradient, being warmer in the lower altitudes, a hypothesised accompanying decrease in decomposition rates did not occur. This could be explained by greater N deposition at the higher elevation sites (estimated

  4. Mobility of trace metals in pore waters of two Central European peat bogs

    International Nuclear Information System (INIS)

    Novak, Martin; Pacherova, Petra

    2008-01-01

    Vertical peat profiles can only be used as archives of past changes in pollution levels if atmogenic elements are immobile after their burial. For mobile elements, similar pore-water concentrations can be expected at different peat depths. Concentrations of Pb, Cu, Zn, Cr, Mn, Fe, Co and Cd were determined in surface bog water and bog pore water 40 cm below surface in two Sphagnum-dominated peat bogs in the Czech Republic. Velke jerabi jezero (VJJ) is an upland bog located in an industrial area, Cervene blato (CB) is a lowland bog located in a rural area. Metal concentrations were monitored seasonally over 3 years (2002-2005) at both sites. Higher concentrations of Pb, Cu, Zn, Cr and Cd and lower concentrations of Mn, Fe and Co were found at the less polluted CB compared to VJJ. No clear-cut seasonality was observed in metal concentrations in bog waters, despite seasonal differences in industrial emission rates of pollutants (more coal burning in winter than in summer). This contrasts with an earlier observation of distinct seasonality in sulfate concentration and isotope composition in these stagnating bog waters. Peat substrate 40 cm below current bog surface represented pre-industrial low-pollution environment, yet pore waters at such depths contained the same metal concentrations as surface waters. The only exception was Pb, whose concentration in water solutes increased with increasing depth. Lack of vertical stratification in pore-water contents of Cu, Zn, Cr, Mn, Fe and Co indicated vertical mobility of these metals

  5. Water exchange in raised bogs: revised views especially in relation to biogeochemistry

    Science.gov (United States)

    Sirin, Andrey; Kravchenko, Irina; Yurova, Alla; Markina, Anastasiya

    2017-04-01

    Raised bogs are one of the most common and exciting mire type within the boreal zone and appear in the other zones including mountain regions in the tropics. They receive water and nutrients from the atmosphere and pore water stored in their domes is spaced above the surrounding area (up to 10 m in height). Traditionally it is assumed that water flow occurs mainly in a peat layer near to the surface and water transport is negligible in deeper layers (lvanov, 1981; Ingram, 1982; etc.). The «acrotelm/catotelm» paradigm on active and inert horizons for the peat above and below the lowest water level is still widely spread in peatland hydrology. However, recent studies have shown that deep water movement is much more dynamic in raised bogs than was previously thought (Sirin et al., 1997, Reeve et al., 2000; etc.). Relying on isotope studies we conclude that all the mounded strata of the raised bogs have relatively active water exchange although water residence time changes with depth. The study included two raised bogs, representing different typical hydrological conditions (underlain by outwash sands and moraine clay) at the Zapadnaya Dvina Peatland Field Station of the Institute of Forest Science RAS located 400 km west of Moscow (56 N, 32 E). Peatlands, among which raised bogs dominate, constitute > 30% of the area, and maximum peat thickness exceeds 7 m. To evaluate water residence time in peat strata specially determined mathematical model which include the equations of water mass and tritium balance, imbedded in a conceptual framework of water dynamics within a raised bog peat body, have been developed and tested. The results from isotope studies (3H, 18O, 2H) were additionally supported by geochemical (pH, Eh, electrical conductivity) and temperature long term monitoring, as well as dissolved CO2 and CH4 monitoring within vertical profiles of the studied raised bogs (Sirin et al., 1998). Later it was also supported by microbiology data of methane cycle in the

  6. Problem of a radiocapacity in a system soil-plant for bog ecosystem

    International Nuclear Information System (INIS)

    Kutlakhmedova-Vyshnyakova, V.

    1998-01-01

    The factors of the various components of a pasture bog ecosystem were evaluated on the example of the Volynsk area. Soil and water were found to contribute appreciably to the accumulation of radionuclides in plants in the bog ecosystem. Evaluation of the integral distribution of radionuclides ( 137 Cs) and the radiocapacity factors of the bog ecosystem components lead to F(soil) = 0.5, F(water) = 0.1, F(plants) = 0.25, and F(root) = 0.15. The radiocapacity factor determines the fraction of radionuclides from a general reserve concentrated in a particular component of the ecosystem. The higher values transfer factors of accumulation for plants in the bog ecosystem in comparison with terrestrial ecosystems (Tf 1.5-18) are noteworthy. Thus the contribution of soil to the formation Tf is from 60 % to 80 %, the remaining pathway in plants being from the water phase. This may be related with the high radiocapacity of soil in the bog ecosystem and (as a corollary) the rather small concentration of radionuclides in water in comparison with soil

  7. Regulation of nitrogen removal and retention in sphagnum bogs and other peatlands

    International Nuclear Information System (INIS)

    Damman, A.W.H.

    1988-01-01

    Nitrogen concentrations range from 0.3-l.3% in ombrotrophic peat of raised bogs. Within ombrogenous bogs, the N concentration of the peat increases in oceanic regions, with the highest concentrations found in blanket bogs on Southern Hemisphere islands. In minerotrophic peat, N concentrations increase with age (depth) as in upland humus. In this paper, I propose that N immobilization is truncated at low levels in ombrotrophic peat because 1) microbial activity is reduced well below that determined by environmental conditions, and 2) N is not limiting decay, in spite of low N concentrations. Consequently, net mineralization of N occurs at C:N quotients 80 to over 100 in inland raised bogs. Nutrient deficiency, probably P deficiency, appears to limit microbial activity and N immobilization. The increased N immobilization in oceanic bogs is attributed to higher Mg inputs that stimulate the biochemical release of P by enzymatic catalysis, and hence increase microbial activity. In ombrotrophi bogs, peat formed during periods of slow accumulation and long residence in the acrotelm has the highest N concentrations but, paradoxically, has also lost more of its original N content than peat that accumulated rapidly. Irregular changes in the anaerobic peat reflect conditions of decay when the peat was in the acrotelm. In a dated profile, N losses were largest during the last 2000 yr. This indicates a change in environmental conditions in the surface peat. Presumably, during this period the bog reached its maximum elevation with respect to the water mound that can be maintained in the peat under the present climatic conditions, and N losses increased as peat accumulation decreased. (author)

  8. Interactions between Nitrogen Fixation and Methane Cycling in Northern Minnesota Peat Bogs

    Science.gov (United States)

    Warren, M. J.; Gaby, J. C.; Lin, X.; Morton, P. L.; Kostka, J. E.; Glass, J. B.

    2014-12-01

    Peatlands cover only 3% of the Earth's surface, yet store a third of soil carbon. Increasing global temperatures have the potential to change peatlands from a net sink to a net source of atmospheric carbon. N is a limiting nutrient in oligotrophic Sphagnum-dominated peatlands and biological N2 fixation likely supplies a significant but unknown fraction of N inputs. Moreover, environmental controls on diazotrophic community composition in N-limited peatlands are poorly constrained. Thus, improved understanding of feedbacks between the CH4 and N cycles is critical for predicting future changes to CH4 flux from peat bogs. We coupled measurements of N2 fixation activity measured by the acetylene (C2H2) reduction assay (ARA) with molecular analyses of expression and diversity of nifH genes encoding the molybdenum (Mo)-containing nitrogenase from two peat bogs in the Marcell Experimental Forest, Minnesota, USA. The top 10 cm of peat was sampled from the high CH4 flux S1 bog and the low CH4 flux Zim bog in April and June 2014. Despite similar N concentrations in the top 10 cm of both bogs (0.5-1.0 μM NO2-+NO3- and 2-3 μM NH4+), the S1 bog displayed variable ARA activity (1-100 nmol C2H4 h-1 g-1) whereas the Zim bog had consistently low ARA activity (Methylocella was the dominant diazotroph in the S1 bog based on high throughput next generation sequencing of nifH cDNA amplicons. Given previous reports of C2H2 inhibition of methanotrophy, we measured CH4 consumption in the presence or absence of 1% C2H2. Preliminary results suggest minimal effect of C2H2 on CH4 oxidation. Future measurements of 15N2 incorporation coupled to molecular analysis will elucidate whether methanotroph diazotrophy was suppressed by C2H2 in ARA incubations.

  9. Factors affecting the sorption of cesium in a nutrient-poor boreal bog

    International Nuclear Information System (INIS)

    Lusa, M.; Bomberg, M.; Virtanen, S.; Lempinen, J.; Aromaa, H.; Knuutinen, J.; Lehto, J.

    2015-01-01

    135 Cs is among the most important radionuclides in the long-term safety assessments of spent nuclear fuel, due to its long half-life of 2.3 My and large inventory in spent nuclear fuel. Batch sorption experiments were conducted to evaluate the sorption behavior of radiocesium ( 134 Cs) in the surface moss, peat, gyttja, and clay layers of 7-m-deep profiles taken from a nutrient-poor boreal bog. The batch distribution coefficient (K d ) values of radiocesium increased as a function of sampling depth. The highest K d values, with a geometric mean of 3200 L/kg dry weight (DW), were observed in the bottom clay layer and the lowest in the 0.5–1.0 m peat layer (50 L/kg DW). The maximum sorption in all studied layers was observed at a pH between 7 and 9.5. The in situ K d values of 133 Cs in surface Sphagnum moss, peat and gyttja samples were one order of magnitude higher than the K d values obtained using the batch method. The highest in situ K d values (9040 L/kg DW) were recorded for the surface moss layer. The sterilization of fresh surface moss, peat, gyttja and clay samples decreased the sorption of radiocesium by 38%, although the difference was not statistically significant. However, bacteria belonging to the genera Pseudomonas, Paenibacillus, Rhodococcus and Burkholderia isolated from the bog were found to remove radiocesium from the solution under laboratory conditions. The highest biosorption was observed for Paenibacillus sp. V0-1-LW and Pseudomonas sp. PS-0-L isolates. When isolated bacteria were added to sterilized bog samples, the removal of radiocesium from the solution increased by an average of 50% compared to the removal recorded for pure sterilized peat. Our results demonstrate that the sorption of radiocesium in the bog environment is dependent on pH and the type of the bog layer and that common environmental bacteria prevailing in the bog can remove cesium from the solution phase. - Highlights: • pH and the type of the bog layer affect

  10. CO2 and CH4 fluxes of contrasting pristine bogs in southern Patagonia (Tierra del Fuego, Argentina)

    Science.gov (United States)

    Münchberger, Wiebke; Blodau, Christian; Kleinebecker, Till; Pancotto, Veronica

    2015-04-01

    South Patagonian peatlands cover a wide range of the southern terrestrial area and thus are an important component of the terrestrial global carbon cycle. These extremely southern ecosystems have been accumulating organic material since the last glaciation up to now and are - in contrast to northern hemisphere bogs - virtually unaffected by human activities. So far, little attention has been given to these pristine ecosystems and great carbon reservoirs which will potentially be affected by climate change. We aim to fill the knowledge gap in the quantity of carbon released from these bogs and in what controls their fluxes. We study the temporal and spatial variability of carbon fluxes in two contrasting bog ecosystems in southern Patagonia, Tierra del Fuego. Sphagnum-dominated bog ecosystems in Tierra del Fuego are similar to the ones on the northern hemisphere, while cushion plant-dominated bogs can almost exclusively be found in southern Patagonia. These unique cushion plant-dominated bogs are found close to the coast and their occurrence changes gradually to Sphagnum-dominated bogs with increasing distance from the coast. We conduct closed chamber measurements and record relevant environmental variables for CO2 and CH4 fluxes during two austral vegetation periods from December to April. Chamber measurements are performed on microforms representing the main vegetation units of the studied bogs. Gas concentrations are measured with a fast analyzer (Los Gatos Ultraportable Greenhouse Gas Analyzer) allowing to accurately record CH4 fluxes in the ppm range. We present preliminary results of the carbon flux variability from south Patagonian peat bogs and give insights into their environmental controls. Carbon fluxes of these two bog types appear to be highly different. In contrast to Sphagnum-dominated bogs, cushion plant-dominated bogs release almost no CH4 while their CO2 flux in both, photosynthesis and respiration, can be twice as high as for Sphagnum

  11. The hydrological and geochemical isolation of a freshwater bog within a saline fen in north-eastern Alberta

    Directory of Open Access Journals (Sweden)

    S.J. Scarlett

    2013-10-01

    Full Text Available In the oil sands development region near Fort McMurray, Alberta, wetlands cover ~62 % of the landscape, and ~95 % of these wetlands are peatlands. A saline fen was studied as a reference site for peatland reclamation. Despite highly saline conditions, a freshwater bog was observed in the path of local saline groundwater flow. The purpose of this study was to identify the hydrological controls that have allowed the development and persistence of a bog in this setting. The presence of bog vegetation and its dilute water chemistry suggest that saline groundwater from the fen rarely enters the bog, which functions predominantly as a groundwater recharge system. Chloride (Cl– and sodium (Na+ were the dominant ions in fen water, with concentrations averaging 5394 and 2307 mg L-1, respectively, while the concentrations in bog water were 5 and 4 mg L-1, respectively. These concentrations were reflected by salinity and electrical conductivity measurements, which in the fen averaged 9.3 ppt, and 15.8 mS cm-1, respectively, and in the bog averaged 0.1 ppt and 0.3 mS cm-1, respectively. A small ridge in the mineral substratum was found at the fen–bog margin, which created a persistent groundwater mound. Under the dry conditions experienced in early summer, groundwater flow was directed away from the bog at a rate of 14.6 mm day-1. The convex water table at the fen-bog margin impeded flow of saline water into the bog and instead directed it around the bog margin. However, the groundwater mound was eliminated during flooding in autumn, when the horizontal hydraulic gradient across the margin became negligible, suggesting the possibility of saline water ingress into the bog under these conditions.

  12. Temperature-Induced Increase in Methane Release from Peat Bogs: A Mesocosm Experiment

    NARCIS (Netherlands)

    van Winden, J.F.; Reichart, G.J.; McNamara, N.P.; Benthien, A.; Sinninghe Damsté, J.S.

    2012-01-01

    Peat bogs are primarily situated at mid to high latitudes and future climatic change projections indicate that these areas may become increasingly wetter and warmer. Methane emissions from peat bogs are reduced by symbiotic methane oxidizing bacteria (methanotrophs). Higher temperatures and

  13. Temperature-induced increase in methane release from peat bogs: A mesocosm experiment

    NARCIS (Netherlands)

    Winden, J.F. van; Reichart, G.-J.; McNamara, N.P.; Benthien, A.; Sinninghe Damsté, J.S.

    2012-01-01

    Peat bogs are primarily situated at mid to high latitudes and future climatic change projections indicate that these areas may become increasingly wetter and warmer. Methane emissions from peat bogs are reduced by symbiotic methane oxidizing bacteria (methanotrophs). Higher temperatures and

  14. Correlation between the morphogenetic types of litter and their properties in bog birch forests

    Science.gov (United States)

    Efremova, T. T.; Efremov, S. P.; Avrova, A. F.

    2010-08-01

    A formalized arrangement of morphogenetic types of litter according to the physicochemical parameters provided their significant grouping in three genetic associations. The litter group (highly decomposed + moderately decomposed) is confined to the tall-grass group of bog birch forests. The rhizomatous (roughly decomposed) litter is formed in the sedge-reed grass bog birch forests. The litter group (peaty + peatified + peat) is associated with the bog-herbaceous-moss group of forest types. The genetic associations of the litters (a) reliably characterize the edaphic conditions of bog birch forests and (b)correspond to formation of the peat of certain ecological groups. We found highly informative the acid-base parameters, the exchangeable cations (Ca2+ + Mg2+) and the total potential acidity, which differentiated the genetic associations of litter practically with 100% probability. The expediency of studying litters under groups of forest types rather than under separate types of bog birch forests was demonstrated.

  15. Species identification of archaeological skin objects from Danish bogs

    DEFF Research Database (Denmark)

    Brandt, Luise Ørsted; Schmidt, Anne Lisbeth; Mannering, Ulla

    2014-01-01

    environment of peat bogs leading to morphological and molecular degradation within the samples. We compared species assignment results of twelve archaeological skin samples from Danish bogs using Mass Spectrometry (MS)-based peptide sequencing, against results obtained using light and scanning electron...... microscopy. While it was difficult to obtain reliable results using microscopy, MS enabled the identification of several species-diagnostic peptides, mostly from collagen and keratins, allowing confident species discrimination even among taxonomically close organisms, such as sheep and goat. Unlike previous...

  16. Regional patterns and controlling factors in plant species composition and diversity in Canadian lowland coastal bogs and laggs

    Directory of Open Access Journals (Sweden)

    S.A. Howie

    2016-11-01

    Full Text Available Inventories of natural assemblages of plant species are critical when planning ecological restoration of bogs. However, little is known about the regional variation in plant communities at the margins (laggs of bogs, even though they are an integral element of raised bog ecosystems. Therefore, we investigated the regional patterns in the plant communities of bogs and laggs, and the factors that control them, for thirteen bogs in coastal British Columbia, Canada. Species richness was significantly higher in the bogs and laggs of the cooler, wetter Pacific Oceanic wetland region. Beta Diversity analyses showed that bogs in the Pacific Oceanic wetland region often shared species with their respective laggs, whereas half of the laggs in the warmer, drier Pacific Temperate wetland region had no species in common with the adjacent bogs and were thus more ecologically distinct from the bog. Primary climatic variables, such as mean annual precipitation, mean annual temperature and latitude, as well as climate-influenced variables, such as pH, peat depth, and Na+ concentrations were the main correlates of plant species composition in the studied bogs. Site-specific factors, particularly depth to water table, and fraction of inorganic material in peat samples, were as strongly related to lagg plant communities as climate, while hydrochemistry appeared to have less influence.

  17. Age estimation by 3D CT-scans of the Borremose Woman, a Danish bog body

    DEFF Research Database (Denmark)

    Villa, Chiara; Møller Rasmussen, Maria; Lynnerup, Niels

    2011-01-01

    Non-invasive estimation of age at death has been carried out by using 3D CT scanning of a bog body discovered in 1948 in a peat bog in Borremose (Denmark). The bog body has been dated to the 8th century BC, in the last part of the Bronze Age. The skeletal structures useful for age estimation have...

  18. The spider fauna of Scragh Bog in Co Westmeath, Ireland (Arachnida: Araneae)

    NARCIS (Netherlands)

    Helsdingen, van P.J.

    1998-01-01

    The spider fauna of Scragh Bog, a quacking bog in Co Westmeath, Ireland, was investigated for the first time. The presence of 53 species could be established, two of which are new to Ireland (Carorita limnaea (Crosby & Bishop), Porrhomma oblitum (O.P.-Cambridge)), while 30 represent new county

  19. Stable strontium isotopic ratios from archaeological organic remains from the Thorsberg peat bog

    DEFF Research Database (Denmark)

    Nosch, Marie-Louise Bech; von Carnap-Bornheim, Claus; Grupe, Gisela

    2007-01-01

    Pilot study analysing stable strontium isotopic ratios from Iron Age textile and leather finds from the Thorsberg peat bog.......Pilot study analysing stable strontium isotopic ratios from Iron Age textile and leather finds from the Thorsberg peat bog....

  20. AHP 40: SOCIALIZING WITH GODS IN THE MONGGHUL BOG RITUAL

    OpenAIRE

    Limusishiden (Li Dechun); Gerald Roche

    2016-01-01

    This article introduces a communal ritual, known as Bog, as practiced among the Mongghul, a linguistically and culturally distinct group of people of the northeast Tibetan Plateau. The main activity of the Bog ritual involves deities and ancestral souls being invited to a sumptuous "banquet" where religious practitioners, called fashi, chant scriptures, sing, dance, joke, and burn incense to delight the "guests." This essay provides a thick description of the ritual. To provide context for th...

  1. Sphagnum bogs of Kelantan, Peninsular Malaysia

    NARCIS (Netherlands)

    Yao, T.L.; Kamarudin, S.; Chew, M.Y.; Kiew, R.

    2009-01-01

    Sphagnum bog, a unique plant community for Peninsular Malaysia was encountered on Padang Ragut, Kelantan. Its topographical features and flora are described, and compared with padang and upper montane floras. It is postulated that the community is derived from upper montane forest and is the result

  2. 137Cs deposition in peat profiles on a raised bog in central Sweden

    International Nuclear Information System (INIS)

    Rosen, K.; Vinichuk, M.; Galan, P.R.; Johanson, K.J.

    2009-01-01

    Distribution of 137 Cs depositions within peat profiles in open bog and nearby (low pine) sites in raised bog are shown and discussed. A possible involvement of Sphagnum moss in radionuclide binding and retention in such nutrient poor ecosystem is suggested. (au)

  3. Subfossil bog-pine horizons document climate and ecosystem changes during the Mid-Holocene

    NARCIS (Netherlands)

    Eckstein, J.; Leuschner, H.H.; Bauerochse, A.; Sass-Klaassen, U.

    2009-01-01

    Extended dendrochronological investigations were performed on subfossil pine entombed in peat layers of former raised bogs in Lower Saxony (NW Germany). The aim was to study of dynamics in bog development in response to local environmental conditions and regional changes in climate throughout the

  4. Effects of elevated CO2 and vascular plants on evapotranspiration in bog vegetation

    NARCIS (Netherlands)

    Heijmans, M.M.P.D.; Arp, W.J.; Berendse, F.

    2001-01-01

    We determined evapotranspiration in three experiments designed to study the effects of elevated CO2 and increased N deposition on ombrotrophic bog vegetation. Two experiments used peat monoliths with intact bog vegetation in containers, with one experiment outdoors and the other in a greenhouse. A

  5. Enhanced sensitivity of a mountain bog to climate change as a delayed effect of road construction

    Directory of Open Access Journals (Sweden)

    P. von Sengbusch

    2015-01-01

    Full Text Available Trees of Pinus rotundata (bog pine characterise many bogs in the mid-altitude mountains of central Europe (Switzerland, East and South Germany, Czech Republic. The research described here focuses on recent changes in the growth of bog pine on the Ennersbacher Moor, a mountain mire in the Black Forest (south-west Germany. An increase in the cover of bog pine is usually caused by drainage and subsequent drawdown of the water table. However, this bog has not been drained or directly disturbed in any other way. One possible explanation is that a road constructed in 1983 along one margin of the bog has diverted part of its water supply. Even though the road was designed to conduct potentially salt-contaminated drainage water away from the bog, its construction did not cause an immediate vegetation response in the 1980s and 1990s. Therefore, I hypothesise that it enhanced the sensitivity of the bog to climatic stress, predisposing it to a succession that was eventually triggered by a series of drought years in 2009–2011. Data collected near the centre of the bog over the period 1998–2014 indicate not only a distinct change in the relationship between height and trunk circumference of the trees, but also an increase of dwarf shrub cover and changes in the composition of Sphagnum communities. Although the pH of near-surface water may have increased slightly over this period, pH and EC values remain within typical ranges for raised bogs in the Black Forest. Examination of peat profiles reveals that the peat is more highly humified now than it was in 2002, and water table records from 2012–2014 show a greater amplitude of fluctuation than water table data collected in 1998–2001. Even though its mean level is only 105 mm below the ground surface, the water table is now observed to fall rapidly to depths of at least 350 mm during both wet and dry summers. Mapping surface (mesotopography and flow lines from the adjacent slope shows that the

  6. Increased tree establishment in Lithuanian peat bogs--insights from field and remotely sensed approaches.

    Science.gov (United States)

    Edvardsson, Johannes; Šimanauskienė, Rasa; Taminskas, Julius; Baužienė, Ieva; Stoffel, Markus

    2015-02-01

    Over the past century an ongoing establishment of Scots pine (Pinus sylvestris L.), sometimes at accelerating rates, is noted at three studied Lithuanian peat bogs, namely Kerėplis, Rėkyva and Aukštumala, all representing different degrees of tree coverage and geographic settings. Present establishment rates seem to depend on tree density on the bog surface and are most significant at sparsely covered sites where about three-fourth of the trees have established since the mid-1990s, whereas the initial establishment in general was during the early to mid-19th century. Three methods were used to detect, compare and describe tree establishment: (1) tree counts in small plots, (2) dendrochronological dating of bog pine trees, and (3) interpretation of aerial photographs and historical maps of the study areas. In combination, the different approaches provide complimentary information but also weigh up each other's drawbacks. Tree counts in plots provided a reasonable overview of age class distributions and enabled capturing of the most recently established trees with ages less than 50 years. The dendrochronological analysis yielded accurate tree ages and a good temporal resolution of long-term changes. Tree establishment and spread interpreted from aerial photographs and historical maps provided a good overview of tree spread and total affected area. It also helped to verify the results obtained with the other methods and an upscaling of findings to the entire peat bogs. The ongoing spread of trees in predominantly undisturbed peat bogs is related to warmer and/or drier climatic conditions, and to a minor degree to land-use changes. Our results therefore provide valuable insights into vegetation changes in peat bogs, also with respect to bog response to ongoing and future climatic changes. Copyright © 2014 Elsevier B.V. All rights reserved.

  7. BOG: R-package for Bacterium and virus analysis of Orthologous Groups

    Directory of Open Access Journals (Sweden)

    Jincheol Park

    2015-01-01

    Full Text Available BOG (Bacterium and virus analysis of Orthologous Groups is a package for identifying groups of differentially regulated genes in the light of gene functions for various virus and bacteria genomes. It is designed to identify Clusters of Orthologous Groups (COGs that are enriched among genes that have gone through significant changes under different conditions. This would contribute to the detection of pathogens, an important scientific research area of relevance in uncovering bioterrorism, among others. Particular statistical analyses include hypergeometric, Mann–Whitney rank sum, and gene set enrichment. Results from the analyses are organized and presented in tabular and graphical forms for ease of understanding and dissemination of results. BOG is implemented as an R-package, which is available from CRAN or can be downloaded from http://www.stat.osu.edu/~statgen/SOFTWARE/BOG/.

  8. Impact of raized bogs on export of carbon and river water chemical composition in Western Siberia

    Science.gov (United States)

    Voistinova, Elena

    2010-05-01

    Bogs play an important role in functioning of the biosphere. Specific geochemical environment of the bogs results in formation of the special biogeochemical cycle of the elements. Processes of decay and transformation of organic material define the reductive conditions of bog water, form and migratory mobility of the chemical elements. Particular interest in recent years is aroused by the question of content and dynamics of the carbon in bog and river water according to indicated natural and climatic changes on the territory. The most important parts of the carbon balance in bog ecosystems together with processes of exhalation from deposit surface in the form of CO2 is its export with river water. The results of research carried out in scientific station "Vasyugansky" in south taiga subzone of Western Siberia showed that chemical composition of raised bog water includes high amounts of total iron (2,13 mg/l), ammonium ions (5,33 mg/l), humic and fulvic acids (5,21 mg/l and 45,8 mg/l), dissolved organic carbon (69,1 mg/l), COD (236,93 mgO/l), there are low mineralization and indicators of pH. Carbon comes in bog water in organic compounds: carboxylic acids, phenols, aromatic and paraffin hydrocarbons, organic phosphates, phthalates and other compounds. Formation of river waters composition in the Western Siberia takes place in the following context: high level of bogged river catchments (sometimes up to 70%), excess humidification and low heat provision. Basing on the results of study of hydrochemical runoff in small and medium rivers with different levels of bogged in river catchments (Chaya, Bakchar, Klyuch, Gavrilovka) it was noted that raised bog influence on river waters chemical composition shows in ion runoff decrease, organic substances runoff increase, increase of amounts of total iron, ammonium irons and water pH indicators decrease. Study of humic matters migration is very important in the context of formation of flexible complexes of humic and fulvic

  9. Nutrient availability at Mer Bleue bog measured by PRSTM probes

    Science.gov (United States)

    Wang, M.; Moore, T. R.; Talbot, J.

    2015-12-01

    Bogs, covering ~0.7 million km2 in Canada, store a large amount of C and N. As nutrient deficient ecosystems, it's critical to examine the nutrient availabilities and seasonal dynamics. We used Plant Root Simulators (PRSTM) at Mer Bleue bog to provide some baseline data on nutrient availability and its variability. In particular, we focused on ammonium, nitrate, phosphate, calcium, magnesium and potassium, iron, sulphate and aluminum. We placed PRS probes at a depth of 5 - 15 cm in pristine plots and plots with long term N, P and K fertilization for 4 weeks and determined the availability of these nutrients, from spring through to fall. Probes were also placed beneath the water table in hummock and hollow microtopography and along a transect including part of the bog which had been drained through the creation of a ditch 80 years ago. The result showed that there was limited available ammonium, nitrate and phosphate in the bog, the seasonal variation of nutrient availabilities probably due to mineralization, an increase in the availability of some nutrients between different water table depths or as a result of drainage, and the relative availability of nutrients compared to the input from fertilization. We suggest that PRS probes could be a useful tool to examine nutrient availability and dynamics in wetlands, with careful consideration of installing condition, for example, proper exposure period, depth relative to water table etc.

  10. The fungal consortium of Andromeda polifolia in bog habitats

    Directory of Open Access Journals (Sweden)

    N.V. Filippova

    2015-09-01

    Full Text Available (1 Andromeda polifolia (bog rosemary is a common plant species in northern circumboreal peatlands. While not a major peat-forming species in most peatlands, it is characterised by a substantial woody below-ground biomass component that contributes directly to the accumulation of organic matter below the moss surface, as well as sclerophyllous leaf litter that contributes to the accumulation of organic matter above the moss surface. Rather little is known about the fungal communities associated with this plant species. Hence, we investigated the fungal consortium of A. polifolia in three distinct vegetation communities of ombrotrophic bogs near Khanty-Mansiysk, West Siberia, Russia, in 2012 and 2013. These vegetation communities were forested bog (Tr = treed, Sphagnum-dominated lawn (Ln, and Eriophorum-Sphagnum-dominated hummock (Er. (2 In total, 37 fungal taxa, belonging to five classes and 16 families, were identified and described morphologically. Seven fungal species were previously known from Andromeda as host. Others are reported for the first time, thus considerably expanding the fungal consortium of this dwarf shrub. Most taxa were saprobic on fallen leaves of A. polifolia found amongst Sphagnum in the bog. Two taxa were parasitic on living plant tissues and one taxon was saprobic on dead twigs. Three taxa, recorded only on A. polifolia leaves and on no other plant species or materials, may be host-specific to this dwarf shrub. (3 A quantitative analysis of the frequency of occurrence of all taxa showed that one taxon (Coccomyces duplicarioides was very abundant, 64 % of the taxa occurred frequently, and 32 % of the taxa occurred infrequently. The mean Shannon diversity index of the community was 2.4. (4 There were no statistical differences in the fungal community composition of A. polifolia in the three vegetation communities investigated in this study. Redundancy analysis suggested that some fungal taxa were positively, and others

  11. Towards sustainable ecological networks of peat bogs in central Russia; development of local environmental action program (LEAP) as a practical tool for protection and restoration of peat bogs in Egorievsk sub region

    NARCIS (Netherlands)

    Butovsky, R.O.; Reijnen, R.; Bondartchuk, E.A.; Otchagov, D.M.; Melik-Bagdasarov, E.M.

    2001-01-01

    In central and northern Meshera the habitats for many characteristic peat bog species now show a very fragmented pattern. As a result, the potential for viable populations of characteristic peat bog species has decreased considerably. Peat-mining and other human influences are the most important

  12. Some results on the isotope studies of water exchange in boreal raised bogs

    International Nuclear Information System (INIS)

    Sirin, A.A.; Vlasova, L.S.; Polyakov, V.A.; Trofimova, A.E.

    2002-01-01

    Raised bogs are rather common and one of the most exciting mire types of the boreal zone. They receive water and nutrients from precipitation and pore water stored in their domes (up to 10 m in height) is spaced above levels of regional ground water or streams draining them. Peatland hydrologists have long assumed that fluid flow occurs mainly in a peat layer near to the surface and water transport is negligible in deeper layers. The 'acrotelm/catotelm' paradigm on active and inert horizons for the peat above and below the lowest water level is still widely spread in peatland hydrology. However, recent studies have shown that deep water movement is much more dynamic in raised bogs than was previously thought. Based on geochemical studies and numerical simulations even temporal reverse of the vertical direction of water fluid flow through the peat as connected to climate fluctuations was assumed. Relying on isotope studies we consider only the mounded strata of the raised bogs to have relatively active water exchange. The study included two raised bogs, representing different local hydrological conditions (underlain by outwash sands and moraine clay) at the Zapadnaya Dvina Peatland Field Station of the Forest Research Institute located 400 km west of Moscow. Peatlands, among which raised bogs dominate, constitute >30% of the area, and maximum peat thickness exceeds 7 m

  13. Origins of mineral matter in peat marsh and peat bog deposits, Spain

    Energy Technology Data Exchange (ETDEWEB)

    Lopez-Buendia, A.M. [Unidad Tecnica del Marmol, AIDICO, Cami de Castella, 4, 03660 Novelda, Alicante (Spain); Whateley, M.K.G. [Rio Tinto Technical Services, Castlemead, Lower Castlemead, BS99 7YR Bristol (United Kingdom); Bastida, J.; Urquiola, M.M. [Dpto. Geologia, Univ. Valencia, Dr. Moliner 50. 46100 Burjasot, Valencia (Spain)

    2007-07-02

    The mineralogy of three back-barrier peat marshes (Torreblanca, Benicasim and Moncofar marshes) from Eastern Spain and one peat bog (Orihuela del Tremedal bog) from central east Spain have been investigated, using X-ray diffraction (XRD) and scanning electronic microscope (SEM) techniques. A combination of XRD methods was used to quantify the mineralogy of dried bulk peat samples. The water source in the peat marshes is both continental and marine. Water is highly mineralised. Water flow is both low and slow (accumulative system). The water source in the peat bog is continental, draining from the hill. The higher concentration of ions in the water of the back-barrier peat marshes leads to a higher concentration of authigenic minerals in the peat marshes compared to the peat bog. Three main mineral origins have been recognized, namely: detrital, syngenetic-epigenetic and biogenic. The more important contribution comes from the detrital system. Biogenic and bio-influenced minerals are the main non-detrital minerals in the peatlands. This paper discusses the biogenic origin of halite (and other minor halides and sulphates, such as, sylvite, carnalite, epsomite, glauberite, mirabilite and anhydrite?) from halophytic plants, as well as amorphous silica (opal-A) from sponge spicules and phytoliths of several plants. Pyrite in the peat bog has both syngenetic and epigenetic origins from plant decomposition and sulphur release. In the peat marsh the pyrite has a syngenetic origin from sulphate reduction (S{sub sulphate} {yields} S{sub pyritic}), and an epigenetic origin in the older peat, from plant decomposition (S{sub organic} {yields} S{sub pyritic}). (author)

  14. Radionuclides in peat bogs and energy peat; Turvesoiden ja polttoturpeen radionuklidit

    Energy Technology Data Exchange (ETDEWEB)

    Helariutta, K.; Rantavaara, A. [Radiation and Nuclear Safety Authority, Helsinki (Finland); Lehtovaara, J. [Vapo Oy, Jyvaeskylae (Finland)

    2000-06-01

    The study was aimed at improving the general view on radionuclides contents in energy peat produced in Finland. The annual harvest of fuel peat in 1994 was studied extensively. Also thirteen peat bogs used for peat production and one bog in natural condition were analysed for vertical distributions of several radionuclides. These distributions demonstrate the future change in radioactivity of energy peat. Both natural nuclides emitting gamma radiation ({sup 238}U, {sup 235}U, {sup 232}Th, {sup 226}Ra, {sup 40}K) and radiocaesium ({sup 137}Cs, {sup 134}Cs) origin in fallout from a nuclear power plant accident (1986) and in atmospheric nuclear weapon tests were analysed. The beta and alpha active natural nuclides of lead and polonium ({sup 210}Pb, {sup 210}Po) were determined on a set of peat samples. These nuclides potentially contribute to radiation exposure through inhalation when partially released to atmosphere during combustion of peat. The activity concentrations of natural radionuclides often increased towards the deepest peat bog layers whereas the radioactive caesium deposited from atmosphere was missing in the deep layers. In undisturbed surface layers of a natural bog and peat production bogs the contents of {sup 210}Pb and {sup 210}Po exceeded those of the deeper peat layers. The nuclides of the uranium series in the samples were generally not in radioactive equilibrium, as different environmental processes change their activity ratios in peat. Radiation exposure from handling and utilisation of peat ash was estimated with activity indices derived from the data for energy peat harvested in 1994. Intervention doses were exceeded in a minor selection of samples due to {sup 137}Cs, whereas natural radionuclides contributed very little to the doses. (orig.)

  15. The importance of groundwater-derived carbon dioxide in the restoration of small Sphagnum bogs

    NARCIS (Netherlands)

    Patberg, Wouter; Baaijens, Gert Jan; Smolders, Alfons J. P.; Grootjans, Ab P.; Elzenga, J. Theo M.

    Essential for successful bog restoration is the reestablishment of Sphagnum mosses. High carbon dioxide availability has been shown to be of great importance for the growth of Sphagnum mosses. In well-developed Sphagnum bogs large amounts of carbon dioxide are produced by (an)aerobic decomposition

  16. The spider fauna of Scragh Bog in Co Westmeath, Ireland (Arachnida: Araneae)

    OpenAIRE

    Helsdingen, van, P.J.

    1998-01-01

    The spider fauna of Scragh Bog, a quacking bog in Co Westmeath, Ireland, was investigated for the first time. The presence of 53 species could be established, two of which are new to Ireland (Carorita limnaea (Crosby & Bishop), Porrhomma oblitum (O.P.-Cambridge)), while 30 represent new county records [Philodromus aureolus (Clerck), Tibellus maritimus (Meigen), Misumena vatia (Clerck), Oxyptila trux (Blackwall), Neon reticulatus (Blackwall), Sitticus caricis (Westring), Pirata hygrophilus Tho...

  17. Measuring restoration progress using pore- and surface-water chemistry across a chronosequence of formerly afforested blanket bogs.

    Science.gov (United States)

    Gaffney, Paul P J; Hancock, Mark H; Taggart, Mark A; Andersen, Roxane

    2018-08-01

    During the restoration of degraded bogs and other peatlands, both habitat and functional recovery can be closely linked with nutrient cycling, which is reflected in pore- and surface-water chemistry. Several peatland restoration studies have shown that the time required for recovery of target conditions is slow (>10 years); for heavily-impacted, drained and afforested peatlands of northern Scotland, recovery time is unknown. We monitored pore- and surface-water chemistry across a chronosequence of formerly drained, afforested bog restoration sites spanning 0-17 years, using a space-for-time substitution, and compared them with open blanket bog control sites. Our aims were to measure rate of recovery towards bog conditions and to identify the best suite of water chemistry variables to indicate recovery. Our results show progress in recovery towards bog conditions over a 0-17 year period post-restoration. Elements scavenged by trees (Mg, Na, S) completely recovered within that period. Many water chemistry variables were affected by the restoration process itself, but recovered within 11 years, except ammonium (NH 4 + ), Zn and dissolved organic carbon (DOC) which remained elevated (when compared to control bogs) 17 years post restoration. Other variables did not completely recover (water table depth (WTD), pH), exhibiting what we term "legacy" effects of drainage and afforestation. Excess N and a lowered WTD are likely to slow the recovery of bog vegetation including key bog plants such as Sphagnum mosses. Over 17 years, we measured near-complete recovery in the chemistry of surface-water and deep pore-water but limited progress in shallow pore-water. Our results suggest that at least >17 years are required for complete recovery of water chemistry to bog conditions. However, we expect that newer restoration methods including conifer harvesting (stem plus brash) and the blocking of plough furrows (to increase the WTD) are likely to accelerate the restoration process

  18. Geochemical characteristics of peat from two raised bogs of Germany

    Science.gov (United States)

    Mezhibor, A. M.

    2016-11-01

    Peat has a wide range of applications in different spheres of human activity, and this is a reason for a comprehensive study. This research represents the results of an ICP-MS study of moss and peat samples from two raised bogs of Germany. Because of the wide use of sphagnum moss and peat, determining their geochemical characteristics is an important issue. According to the results obtained, we can resume that the moss samples from Germany are rich in Cu, As, Y, Zr, Nb, and REE. The geochemical composition of the bogs reflects the regional environmental features and anthropogenic influence.

  19. Can restoration convert a degraded bog in southern Bavaria to a carbon sink and climate cooler?

    Science.gov (United States)

    Förster, Christoph; Drösler, Matthias

    2014-05-01

    The peatland area of Germany is about 14.000 km² (Succow & Joosten 2001) with 8% natural like bogs and 4% natural like fens (Höper 2006). All other peatland areas are more or less intensively used and thus, lost their sink function for carbon. If, theoretically, all German peatlands would be rewetted, this restoration would lead to a carbon mitigation of 9.5 Mio. t CO2-C equivalents (Freibauer et al. 2009). In test areas like the studied bog, the viability and potential of peatland restoration for climate mitigation can be proofed. The investigated bog is situated close to the Bavarian Alps; one part of this bog is extensively used and had been rewetted in 1993 except of a small stripe; management was stopped totally at another stripe. The second part of this bog had been drained without any further use. Here a Calluna heath established, accompanied by Pine trees. The restoration of this bog heath was done in two time steps; here a chronosequence of succession after restoration at different water table levels was investigated. To get to the greenhouse gas (GHG) balances of CO2 CH4 and N2O, gas flux measurements were done for two years using the chamber technique of Drösler (2005). At both areas, the degraded sites were sources for GHG (+203 to +736 g CO2-C-equiv m-2 a-1). Restoration reduced these emissions depending on water table and succession of bog species (-51 to +557 g CO2-C-equiv m-2 a-1). Depending on the vegetation's vitality GHG balances of already established natural like sites varied in between the years (-189 to +264 g CO2-C-equiv m-2 a-1) mainly driven by the oscillation of their water table. Stop of management and development of Sphagnum communities turned most of the sites into sinks for GHG (-216 to +7 g CO2-C-equiv m-2 a-1). Thus restoration turned degraded bogs efficiently to carbon sinks and climate coolers in dependence of a proper water table management, withdrawal of land use and vegetation succession. Key words: bog, greenhouse gases

  20. Expansion of Sphagnum fallax in bogs: striking the ballance between N and P availability

    NARCIS (Netherlands)

    Limpens, J.; Tomassen, H.B.M.; Berendse, F.

    2003-01-01

    Nitrogen deposition may cause shifts in the Sphagnum species composition of bogs, ultimately affecting the conservation value of these systems. We studied the effects of N and P on the expansion of S. fallax and S. flexuosum in bogs. We related historical census data of S. fallax, S. flexuosum, and

  1. Southern Hemisphere bog persists as a strong carbon sink during droughts

    Science.gov (United States)

    Goodrich, Jordan P.; Campbell, David I.; Schipper, Louis A.

    2017-10-01

    Peatland ecosystems have been important global carbon sinks throughout the Holocene. Most of the research on peatland carbon budgets and effects of variable weather conditions has been done in Northern Hemisphere Sphagnum-dominated systems. Given their importance in other geographic and climatic regions, a better understanding of peatland carbon dynamics is needed across the spectrum of global peatland types. In New Zealand, much of the historic peatland area has been drained for agriculture but little is known about rates of carbon exchange and storage in unaltered peatland remnants that are dominated by the jointed wire rush, Empodisma robustum. We used eddy covariance to measure ecosystem-scale CO2 and CH4 fluxes and a water balance approach to estimate the sub-surface flux of dissolved organic carbon from the largest remaining raised peat bog in New Zealand, Kopuatai bog. The net ecosystem carbon balance (NECB) was estimated over four years, which included two drought summers, a relatively wet summer, and a meteorologically average summer. In all measurement years, the bog was a substantial sink for carbon, ranging from 134.7 to 216.9 gC m-2 yr-1, owing to the large annual net ecosystem production (161.8 to 244.9 gCO2-C m-2 yr-1). Annual methane fluxes were large relative to most Northern Hemisphere peatlands (14.2 to 21.9 gCH4-C m-2 yr-1), although summer and autumn emissions were highly sensitive to dry conditions, leading to very predictable seasonality according to water table position. The annual flux of dissolved organic carbon was similar in magnitude to methane emissions but less variable, ranging from 11.7 to 12.8 gC m-2 yr-1. Dry conditions experienced during late summer droughts led to significant reductions in annual carbon storage, which resulted nearly equally from enhanced ecosystem respiration due to lowered water tables and increased temperatures, and from reduced gross primary production due to vapor pressure deficit-related stresses to the

  2. The microbial impact on the sorption behaviour of selenite in an acidic, nutrient-poor boreal bog

    International Nuclear Information System (INIS)

    Lusa, M.; Bomberg, M.; Aromaa, H.; Knuutinen, J.; Lehto, J.

    2015-01-01

    79 Se is among the most important long lived radionuclides in spent nuclear fuel and selenite, SeO 3 2− , is its typical form in intermediate redox potential. The sorption behaviour of selenite and the bacterial impact on the selenite sorption in a 7-m-deep profile of a nutrient-poor boreal bog was studied using batch sorption experiments. The batch distribution coefficient (K d ) values of selenite decreased as a function of sampling depth and highest K d values, 6600 L/kg dry weight (DW), were observed in the surface moss and the lowest in the bottom clay at 1700 L/kg DW. The overall maximum sorption was observed at pH between 3 and 4 and the K d values were significantly higher in unsterilized compared to sterilized samples. The removal of selenite from solution by Pseudomonas sp., Burkholderia sp., Rhodococcus sp. and Paenibacillus sp. strains isolated from the bog was affected by incubation temperature and time. In addition, the incubation of sterilized surface moss, subsurface peat and gyttja samples with added bacteria effectively removed selenite from the solution and on average 65% of selenite was removed when Pseudomonas sp. or Burkholderia sp. strains were used. Our results demonstrate the important role of bacteria for the removal of selenite from the solution phase in the bog environment, having a high organic matter content and a low pH. - Highlights: • Sterilization of bog samples inhibited the SeO 3 2− removal from simulated bog water. • Bacteria isolated from the bog samples removed selenite from the solution. • Bacteria affect the removal of SeO 3 2− from the solution in a nutrient-poor bog. • Selenite is reduced by the bacteria present in the bog both under oxic and anoxic conditions within the different microniches therein. • That is a prerequisite to read the record of the deformational history in metamorphic rocks

  3. Hounsfield Units ranges in CT-scans of bog bodies and mummies

    DEFF Research Database (Denmark)

    Villa, Chiara; Lynnerup, Niels

    2012-01-01

    Mummification processes, either artificial or natural, preserve the tissues from postmortem decay, but change them from their original state. In this study we provided the first comprehensive set of Hounsfield Unit (HU) ranges specific for tissues mummified under different environmental conditions...... (peat bog, cold-dry and hot-dry environment). We also analyzed the impact of different museal preservation techniques on the HU ranges, as e.g. in the Tollund Man and Grauballe Man, two bog bodies from Denmark. The HU results for mummies were compared with HU results from forensic cases, cremated...

  4. Decadal changes in peat carbon accrual rates in bogs in Northern Minnesota

    Science.gov (United States)

    Fissore, C.; Nater, E. A.; McFarlane, K. J.

    2017-12-01

    Throughout the Holocene, peatland ecosystems have accumulated substantial amounts of carbon (C) and currently store about one third of all soil organic carbon (SOC) worldwide. Large uncertainty still persists on whether peatland ecosystems located in northern latitudes will continue to act as C sinks, or if the effects of global warming will have greater effects on decomposition processes than on net ecosystem production. We investigated decadal C accrual rates of the top 25 cm of peats in three Sphagnum-rich peatlands located in Northern Minnesota (two ombrotrophic bogs and one fen). We used radiocarbon analysis of Sphagnum cellulose and model fitting to determine peat ages, and peat FTIR spectroscopy to determine humification indices and relative decomposition of peat samples with depth. We had the scope to detect whether recent warming has had an effect on peat decomposition and C accumulation rates. Modeled C accumulation rates in the three peatlands during the past five decades ranged between 78 and 107 g C m-2 yr-1 in the top 25 cm analyzed in this study, values that are higher than the 22 to 29 g C m-2 yr-1 obtained for long-term (millennial) accumulations for the entire bog profiles. Peat IR spectra and C:N ratios confirm low levels of decomposition across the bog sites, especially in the uppermost parts of the peat. The fen site showed very limited decomposition across the entire sampled profile. Higher rates of C accumulation, combined with low decomposition rates close to the surface provide a good estimate of net primary productivity. As substrate decomposition progresses over time, net rates of accumulation decrease. Peat decomposition was more pronounced in the lower depths of the sampled cores in the two ombrotrophic bogs than in the fen, likely an effect of larger temporal variation in water table depth in the bogs than in the fen. Some of the variation in C accumulation and decomposition observed in our bogs and fen suggests that future C

  5. Carbon and Oxygen Isotope Dendrochronology in Sub-Fossil Bog Oak Tree Rings - A Preliminary Study

    NARCIS (Netherlands)

    Sass, U.G.W.; Poole, I.; Wils, T.; Helle, G.; Schleser, G.H.; Bergen, van P.

    2005-01-01

    Isotope dendroclimatology is a relatively new field investigating environmental factors that control the radial growth of trees. Tree-ring series of sub-fossil bog oaks can be dated from sites across northwest Europe indicating that the environmental change(s) were regional rather than local. Bog

  6. Ecological networks and nature policy in central Russia : peat bogs in central and northern Meshera

    NARCIS (Netherlands)

    Butovsky, R.O.; Reijnen, R.; Otchagov, D.M.; Aleshenko, G.M.; Melik-Bagdasarov, E.

    2001-01-01

    In central and northern Meshera, Russia, the habitat of many characteristic peat bog species now show a very fragmented pattern. Peat mining and other human influences are the most important causes. As a result the potentials for viable populations ofcharacteristic peat bog species have decreased

  7. Bacterial Abundance and Activity across Sites within Two Northern Wisconsin Sphagnum Bogs.

    Science.gov (United States)

    Fisher; Graham; Graham

    1998-11-01

    Abstract Bacterial abundance, temperature, pH, and dissolved organic carbon (DOC) concentration were compared across surface sites within and between two northern Wisconsin Sphagnum peatlands over the summer seasons in 1995 and 1996. Sites of interest were the Sphagnum mat surface, the water-filled moat (lagg) at the bog margin, and the bog lake littoral zone. Significant differences in both bacterial populations and water chemistry were observed between sites. pH was highest in the lake and lowest in the mat at both bogs; the opposite was true for DOC. Large populations of bacteria were present in surface interstitial water from the mat; abundance in this site was consistently higher than in the moat or lake. Bacterial abundance also increased across sites of increasing DOC concentration and declining pH. Bacterial activities (rates of [3H]leucine incorporation) and growth in dilution cultures (with grazers removed) were also assessed in lake, moat, and mat sites. Results using these measures generally supported the trends observed in abundance, although high rates of [3H]leucine incorporation were recorded in the moat at one of the bogs. Our results indicate that bacterial populations in Sphagnum peatlands are not adversely affected by acidity, and that DOC may be more important than pH in determining bacterial abundance in these environments.

  8. Peat bogs and their organic soils: Archives of atmospheric change and global environmentalsignificance (Philippe Duchaufour Medal Lecture)

    Science.gov (United States)

    Shotyk, William

    2013-04-01

    A bog is much more than a waterlogged ecosystem where organic matter accumulates as peat. Peatlands such as bogs represent a critical link between the atmosphere, hydrosphere, and biosphere. Plants growing at the surface of ombrotrophic bogs receive nutrients exclusively from the atmosphere. Despite the variations in redox status caused by seasonal fluctuations in depth to water table, the low pHof the waters, and abundance of dissolved organic matter, bogs preserve a remarkably reproducible history of atmospheric pollution, climate change, landscape evolution and human history. For example, peat cores from bogs in Europe and North America have provided detailed reconstructions of the changing rates and sources of Ag, Cd, Hg, Pb, Sb, and Tl, providing new insights into the geochemical cycles of these elements, including the massive perturbations induced by human activities beginning many thousands of years ago. Despite the low pH, and perhaps because of the abundance of dissolved organic matter, bogs preserve many silicate and aluminosilicate minerals which renders them valuable archives of atmospheric dust deposition and the climate changes which drive them. In the deeper, basal peat layers of the bog, in the minerotrophic zone where pore waters are affected bymineral-water interactions in the underlying and surrounding soils and sediments, peat serves as animportant link to the hydrosphere, efficiently removing from the imbibed groundwaters such trace elements as As, Cu, Mo, Ni, Se, V, and U. These removal processes, while incompletely understood, are so effective that measuring the dissolved fraction of trace elements in the pore waters becomes a considerable challenge even for the most sophisticated analytical laboratories. While the trace elements listed above are removed from groundwaters (along with P and S), elements such as Fe and Mn are added to the waters because of reductive dissolution, an important first step in the formation of lacustrine Fe and Mn

  9. Behaviour of carbon dioxide and water vapour flux densities from a disturbed raised peat bog

    NARCIS (Netherlands)

    Nieveen, J.P.; Jacobs, A.F.G.

    2002-01-01

    Measurements of carbon dioxide and water vapour flux densities were carried out for a disturbed raised peat bog in the north of the Netherlands during an 18 month continuous experiment. Tussock grass (sp. Molinea caerulae) mainly dominated the vegetation of the bog area. The maximum leaf area index

  10. Dibasic Ammonium Phosphate Application Enhances Aromatic Compound Concentration in Bog Bilberry Syrup Wine

    Directory of Open Access Journals (Sweden)

    Shao-Yang Wang

    2016-12-01

    Full Text Available A nitrogen deficiency always causes bog bilberry syrup wine to have a poor sensory feature. This study investigated the effect of nitrogen source addition on volatile compounds during bog bilberry syrup wine fermentation. The syrup was supplemented with 60, 90, 120 or 150 mg/L dibasic ammonium phosphate (DAP before fermentation. Results showed that an increase of DAP amounts accelerated fermentation rate, increased alcohol content, and decreased sugar level. Total phenol and total flavonoid content were also enhanced with the increase of DAP amounts. A total of 91 volatile compounds were detected in the wine and their concentrations were significantly enhanced with the increase of DAP. Ethyl acetate, isoamyl acetate, phenethyl acetate, ethyl butanoate, ethyl hexanoate, ethyl octanoate, ethyl decanoate, isobutanol, isoamyl alcohol, levo-2,3-butanediol, 2-phenylethanol, meso-2,3-butanediol, isobutyric acid, hexanoic acid, and octanoic acid exhibited a significant increase of their odor activity value (OAV with the increase of DAP amounts. Bog bilberry syrup wine possessed fruity, fatty, and caramel flavors as its major aroma, whereas a balsamic note was the least present. The increase of DAP amounts significantly improved the global aroma attributes, thereby indicating that DAP supplementation could promote wine fermentation performance and enhance the sensory quality of bog bilberry syrup wine.

  11. Assessing the conservation potential of damaged peat bog networks in Central and Northern Meshera (Central Russia)

    NARCIS (Netherlands)

    Butovsky, R.O.; Reijnen, M.J.S.M.; Aleshenko, G.M.; Melik-Bagdasarov, E.M.; Otchagov, D.M.

    2004-01-01

    Peat bogs are one of the most characteristic ecosystems of Central Russian landscape. Because of peat mining and transformation of peat bogs into agricultural land after drainage, suitable habitats for several characteristic species now show a very fragmented pattern. The potentials for viable

  12. Numerical study of heat transfer characteristics in BOG heat exchanger

    Science.gov (United States)

    Yan, Yan; Pfotenhauer, John M.; Miller, Franklin; Ni, Zhonghua; Zhi, Xiaoqin

    2016-12-01

    In this study, a numerical study of turbulent flow and the heat transfer process in a boil-off liquefied natural gas (BOG) heat exchanger was performed. Finite volume computational fluid dynamics and the k - ω based shear stress transport model were applied to simulate thermal flow of BOG and ethylene glycol in a full-sized 3D tubular heat exchanger. The simulation model has been validated and compared with the engineering specification data from its supplier. In order to investigate thermal characteristics of the heat exchanger, velocity, temperature, heat flux and thermal response were studied under different mass flowrates in the shell-side. The shell-side flow pattern is mostly determined by viscous forces, which lead to a small velocity and low temperature buffer area in the bottom-right corner of the heat exchanger. Changing the shell-side mass flowrate could result in different distributions of the shell-side flow. However, the distribution in the BOG will remain in a relatively stable pattern. Heat flux increases along with the shell-side mass flowrate, but the increase is not linear. The ratio of increased heat flux to the mass flow interval is superior at lower mass flow conditions, and the threshold mass flow for stable working conditions is defined as greater than 0.41 kg/s.

  13. Association of postfire peat accumulation and microtopography in boreal bogs

    Energy Technology Data Exchange (ETDEWEB)

    Benscoter, B.W.; Vitt, D.H. [Southern Illinois Univ., Carbondale, IL (United States). Dept. of Plant Biology; Wieder, R.K. [Villanova Univ., Villanova, PA (United States). Dept. of Biology

    2005-09-01

    Fire impacts peatland species composition by differentially removing vegetation and resetting succession, which results in peat accumulation changes. A study of peat accumulation and microtopography in 2 burned bogs in Alberta was presented in this paper. Measurements of current and historic microtopography were made, and cores were collected along the gradient to identify the depth of peat accumulated since fires, as well as to assess its properties. It was observed that current microtopography was significant and correlated with the immediate post-fire surface relief. Differences in the magnitude of variability between sites suggested that differential rates of growth between features were exacerbated between sites and reflected in bog microtopography. Rates of organic matter accumulation ranged from 156 to 257 g/m{sup 2} per year, and were elevated but comparable to recent published rates. It was noted that organic matter content and accumulation rates were greater for hummocks than hollows at the Athabasca bog, but the difference between features diminished at Sinkhole Lake. It was concluded that the pattern and properties of peat accumulation and microtopography post-fire is topographical, and hence species dependent. Rates of change are dependent on fire severity and its effect on vegetation composition and succession. 33 refs., 4 figs.

  14. Extracting phosphoric iron under laboratorial conditions smelting bog iron ores

    International Nuclear Information System (INIS)

    Török, B; Thiele, A

    2013-01-01

    In recent years it has been indicated by archaeometric investigations that phosphoric-iron (P-iron, low carbon steel with 0,5-1,5wt% P), which is an unknown and unused kind of steel in the modern industry, was widely used in different parts of the world in medieval times. In this study we try to explore the role of phosphorus in the arhaeometallurgy of iron and answer some questions regarding the smelting bog iron ores with high P-content. XRF analyses were performed on bog iron ores collected in Somogy county. Smelting experiments were carried out on bog iron ores using a laboratory model built on the basis of previously conducted reconstructed smelting experiments in copies of excavated furnaces. The effect of technological parameters on P-content of the resulted iron bloom was studied. OM and SEM-EDS analyses were carried out on the extracted iron and slag samples. On the basis of the material analyses it can be stated that P-iron is usually extracted but the P-content is highly affected by technological parameters. Typical microstructures of P-iron and of slag could also be identified. It could also be established that arsenic usually solved in high content in iron as well

  15. DATING RECENT PEAT ACCUMULATION IN EUROPEAN OMBROTROPHIC BOGS

    NARCIS (Netherlands)

    van der Plicht, Johannes; Yeloff, Dan; van der Linden, Marjolein; van Geel, Bas; Brain, Sally; Chambers, Frank M.; Webb, Julia; Toms, Phillip; Hatté, C.; Jull, A.J.T.

    2013-01-01

    This study compares age estimates of recent peat deposits in 10 European ombrotrophic (precipitation-fed) bogs produced using the C-14 bomb peak, Pb-210, Cs-137, spheroidal carbonaceous particles (SCPs), and pollen. At 3 sites, the results of the different dating methods agree well. In 5 cores,

  16. Numerical simulation and experimental investigation on suction heating of a BOG compressor

    International Nuclear Information System (INIS)

    Jia, Xiaohan; Zhao, Bin; Feng, Jianmei; Zheng, Sulu; Peng, Xueyuan

    2016-01-01

    Highlights: • An investigation focusing on suction heating of a BOG compressor is carried out. • There is frost on the cylinder cover as the compressor at lower suction temperature. • The suction and discharge flow rate decrease with rising suction temperature. • The volumetric efficiency has a maximum value with increasing suction temperature. • The temperature coefficient increased with suction temperature or rotational speed. - Abstract: One of the key components of a liquefied natural gas (LNG) receiving terminal is the boil-off gas (BOG) compressor, which is used to pump out the BOG from the LNG storage tank to ensure safety in the transportation and receiving systems. Owing to the ultra-low suction temperature, the heat exchange between the intake gas and the cylinder, piston, and cylinder cover cannot be ignored as in normal conditions. This paper presents an investigation focusing on suction heating of the BOG compressor. A finite element model with dynamic mesh was established to simulate the suction process. At the same time, a performance test rig was built to study the characteristics of the BOG compressor under low suction temperature conditions and verify the numerical model. Consequently, the results of the simulation were in good agreement with experimental results. Both results implied that the temperature of cylinder surface increased starting from the cylinder cover to the crankcase. In addition, at lower suction temperature, the temperature difference between various points on the cylinder surface and cylinder cover was much larger than that at higher suction temperature. With increasing suction temperature, the temperature coefficient increased markedly, and the difference between gas temperatures at the beginning and end of the suction process, as well as the compressor flow rate, decreased significantly; however, the volumetric efficiency increased first and then decreased. Furthermore, the temperature coefficient clearly increased

  17. Aged anthropogenic iodine in a boreal peat bog

    International Nuclear Information System (INIS)

    Maillant, S.; Sheppard, M.I.; Denys, S.; Leclerc Cessac, E.

    2004-01-01

    Iodine-129 is a radionuclide of major concern in the international safety assessments for deep geological storage and disposal of nuclear waste because it migrates quickly through the geosphere to the biosphere and then from the soil to humans through the food-chain. However, in organic soils the 129 I may be immobilized over a long time period, and so these soils represent a potential accumulation point in the biosphere. Effects of long residence times of iodine in soils are scarce. The present paper gives some insight on the aging of stable iodine, under natural conditions. Stable iodine was introduced as KI in 1987 at the base of a small natural sphagnum bog to simulate arrival of iodine via a groundwater discharge from the geosphere. Previous data revealed the spread of the iodine outwards spatially from the basal spike and also recorded its rise towards the bog surface. Fifteen years later, the groundwater, the soil and the vegetation have been sampled and analyzed for iodine. The results we will present give insight on the mobility of 'aged' iodine with time, the retention properties of the peat, and provide iodine transfer factors for native boreal plant species. The data show iodine: - continues to slowly spread from the spike after 15 years, - is more strongly retained on the solid phase at the surface than at depth, - the chemical structure of the peat may influence the retention of iodine as shown by NMR analysis, - iodine retention has become greater with time, and - herbaceous species are the greatest accumulators. This study demonstrates bogs present good sinks for iodine and limit the transfer of iodine to some of the 'wildlife' food-chains. (author)

  18. What rules GHG-(greenhouse gas)-fluxes in a prealpine bog - management or watertable?

    Science.gov (United States)

    Förster, Christoph; Drösler, Matthias

    2010-05-01

    Being an important sink of carbon, the small stripe of bogs in the foreland of the Alps plays an important role for the carbon balance of Germany. A big part was drained for peat-use and to get agricultural land in the last centuries. Restoration of these degraded bogs can help to rebuild this function, whereas the watertable is an important co-factor for the amount of mitigation of greenhouse gases (CO2, CH4 and N2O). To estimate GHG-balances gas-flux measurements, using the chamber method developed by Drösler (2005) were done in 2007 and 2008 on a degraded bog-meadow, which was partly rewetted in 1993 and which is still managed in large areas. This mosaic of restored, drained and managed areas showed big differences in their carbon-balances from a high source (~ 500 g CO2-C m-2 a-1) to a moderate sink (~ -200 g CO2-C m-2 a-1). Where the management was stopped in 1993, some Sphagnum-communities developed which helped to turn these areas from moderate sources (47 g CO2-C m-2 a-1) or sinks (-58 g CO2-C m-2 a-1) to permanent sinks with uptakes between (-150 and -250 g CO2-C m-2 a-1). Key words: bog, carbon-balance, greenhouse gases, restoration, watertable

  19. Do plant traits explain tree seedling survival in bogs?

    NARCIS (Netherlands)

    Limpens, J.; van Egmond, E.; Li, Bingxi; Holmgren, M.

    2014-01-01

    Moss-dominated peat bogs store approximately 30% of global soil carbon. A climate induced-shift from current moss-dominated conditions to tree-dominated states is expected to strongly affect their functioning and carbon sequestration capacity. Consequently, unravelling the mechanisms that may

  20. Natural and artificial radionuclides in forest and bog soils: tracers for migration processes and soil development

    International Nuclear Information System (INIS)

    Schleich, N.; Degering, D.; Unterricker, S.

    2000-01-01

    Radionuclide distributions in undisturbed forest and bog soils, mostly situated in Saxony, Germany (Erzgebirge), were studied. Low concentrations of naturally-occurring U and Th decay series nuclides, including 210 Pb, and artificial radioisotopes ( 125 Sb, 134 Cs, 137 Cs, 241 Am) were determined using low-level γ-spectrometry. In addition, the activities of 238 Pu and 239,240 Pu were determined by radiochemical separation and α-spectrometry. 14 C and excess 210 Pb dating methods were used to date the sampled bog profiles. The different radionuclides show characteristic depth distributions in the forest and bog soil horizons, which were sub-sampled as thin slices. 125 Sb, 241 Am, 238 Pu and 239,240 Pu are strongly fixed in soil organic matter. In spruce forest soils, the influence of soil horizons with distinct properties dominates the vertical time-dependent distribution. In ombrotrophic bogs, the peak positions correlated with the year of maximum input of each nuclide. The Sb, Am and Pu ''time markers'' and the 14 C and 210 Pb dating results correspond very well. Although Cs seems to be relatively mobile in organic as well as mineral forest soil horizons, it is enriched in the organic material. In ombrotrophic bogs, Cs is very mobile in the peat deposit. In Sphagnum peat, Cs is translocated continuously towards the growing apices of the Sphagnum mosses, where it is accumulated. (orig.)

  1. Do plant traits explain tree seedling survival in bogs?

    NARCIS (Netherlands)

    Limpens, J.; Egmond, van E.; Li, B.; Holmgren, M.

    2014-01-01

    1.Moss-dominated peat bogs store approximately 30% of global soil carbon. A climate induced shift from current moss-dominated conditions to tree-dominated states is expected to strongly affect their functioning and carbon sequestration capacity. Consequently, unraveling the mechanisms that may

  2. Do plant traits explain tree seedling survival in bogs?

    NARCIS (Netherlands)

    Limpens, J.; Egmond, van E.; Li, B.; Holmgren, M.

    2013-01-01

    Moss-dominated peat bogs store approximately 30% of global soil carbon. A climate induced shift from current moss-dominated conditions to tree-dominated states is expected to strongly affect their functioning and carbon sequestration capacity. Consequently, unraveling the mechanisms that may explain

  3. Ground-penetrating radar study of the Rahivere peat bog, eastern Estonia

    Directory of Open Access Journals (Sweden)

    Jüri Plado

    2011-03-01

    Full Text Available The current case study presents results of the ground-penetrating radar (GPR profiling at one of the Saadjärve drumlin field interstitial troughs, the Rahivere bog, eastern Estonia. The study was conducted in order to identify the bog morphology, and the thickness and geometry of the peat body. The method was also used to describe the applicability of GPR in the evaluation of the peat deposit reserve as the Rahivere bog belongs among the officially registered peat reserves. Fourteen GPR profiles, ~ 100 m apart and oriented perpendicular to the long axis of the depression, covering the bog and its surrounding areas, were acquired. In order to verify the radar image interpretation as well as to evaluate the velocity of electromagnetic waves in peat, a common source configuration was utilized and thirteen boreholes were drilled on the GPR profiles. A mean value of 0.036 m ns–1 corresponding to relative dielectric permittivity of 69.7 was used for the time–depth conversion. Radar images reveal major reflection from the peat–soil interface up to a depth of about 4 m, whereas drillings showed a maximum thickness of 4.5 m of peat. Minor reflections appear from the upper peat and mineral soil. According to the borehole data, undecomposed peat is underlain by decomposed one, but identifying them by GPR is complicated. Mineral soil consists of glaciolimnic silty sand in the peripheral areas of the trough, overlain by limnic clay in the central part. The calculated peat volumes (1 200 000 m3 were found to exceed the earlier estimation (979 000 m3 that was based solely on drilling data. Ground-penetrating radar, as a method that allows mapping horizontal continuity of the sub-peat interface in a non-destructive way, was found to provide detailed information for evaluating peat depth and extent.

  4. Towards the identification of dyestuffs in Early Iron Age Scandinavian peat bog textiles

    DEFF Research Database (Denmark)

    Mannering, Ulla; Gleba, Margarita; Vanden Berghe, Ina

    2009-01-01

    A large systematic dye investigation of prehistoric Danish and Norwegian bog textiles was carried out using high performance liquid chromatography with photo diode array detection. After the selection of the most suitable protocol for dye extraction and HPLC analysis for this specific group of ar...... of biological dye sources in Early Iron Age Scandinavia. The results clearly indicate that most Scandinavian peat bog textiles originally were dyed and that already during the 1st millennium BC, the populations in Scandinavia were familiar with the dyeing technology....

  5. Bog bilberry phenolics, antioxidant capacity and nutrient profile

    Czech Academy of Sciences Publication Activity Database

    Colak, N.; Torun, H.; Grúz, Jiří; Strnad, Miroslav; Hermosín-Gutiérrez, I.; Hayirlioglu-Ayaz, S.; Ayaz, F. A.

    2016-01-01

    Roč. 201, JUN 15 (2016), s. 339-349 ISSN 0308-8146 R&D Projects: GA ČR GA14-34792S; GA MŠk(CZ) LO1204; GA MŠk LK21306 Institutional support: RVO:61389030 Keywords : Vaccinium uliginosum * Bog bilberry * Phenolic acid Subject RIV: EF - Botanics Impact factor: 4.529, year: 2016

  6. The new European Competence Centre for Moor and Climate - A European initiative for practical peat bog and climate protection

    Science.gov (United States)

    Smidt, Geerd; Tänzer, Detlef

    2013-04-01

    The new European Competence Centre for Moor and Climate (EFMK) is an initiative by different local communities, environmental protection NGOs, agricultural services, and partners from the peat and other industries in Lower Saxony (Germany). The Centre aims to integrate practical peat bog conservation with a focus on green house gas emission after drainage and after water logging activities. Together with our partners we want to break new ground to protect the remaining bogs in the region. Sphagnum mosses will be produced in paludiculture on-site in cooperation with the local peat industry to provide economic and ecologic alternatives for peat products used in horticulture business. Land-use changes are needed in the region and will be stimulated in cooperation with agricultural services via compensation money transfers from environmental protection funds. On a global scale the ideas of Carbon Credit System have to be discussed to protect the peat bogs for climate protection issues. Environmental education is an important pillar of the EFMK. The local society is invited to explore the unique ecosystem and to participate in peat bog protection activities. Future generations will be taught to understand that the health of our peat bogs is interrelated with the health of the local and global climate. Besides extracurricular classes for schools the centre will provide infrastructure for Master and PhD students, as well for senior researchers for applied research in the surrounding moor. International partners in the scientific and practical fields of peat bog ecology, renaturation, green house gas emissions from peat bogs, and environmental policy are invited to participate in the European Competence Center for Moor and Climate.

  7. Towards a conceptual model of hydrological change on an abandoned cutover bog, Quebec

    Science.gov (United States)

    van Seters, Tim E.; Price, Jonathan S.

    2002-07-01

    Cutover bogs do not return to functional peatland ecosystems after abandonment because re-establishment of peat-forming mosses is poor. This paper presents a conceptual model of bog disturbance caused by peat harvesting (1942-1972), and the hydrological evolution that occurred after abandonment (1973-1998). Two adjacent bogs of similar size and origin, one harvested and the other essentially undisturbed, provide the basis for understanding what changes occurred. The model is based on historical trends evident from previous surveys of land-use, bog ecology and resource mapping; and from recent hydrological and ecological data that characterize the current condition. Water balance data and historical information suggest that runoff increased and evapotranspiration decreased following drainage, but tended towards pre-disturbance levels following abandonment, as vegetation recolonized the surface and drainage became less efficient over time. Dewatering of soil pores after drainage caused shrinkage and oxidation of the peat and surface subsidence of approximately 80 cm over 57 years. Comparisons with a nearby natural bog suggest that bulk density in the upper 50 cm of cutover peat increased from 0·07 to 0·13 g cm-3, specific yield declined from 0·14 to 0·07, water table fluctuations were 67% greater, and mean saturated hydraulic conductivity declined from 4·1 × 10-5 to 1·3 × 10-5 cm s-1. More than 25 years after abandonment, Sphagnum mosses were distributed over broad areas but covered less than 15% of the surface. Areas with good Sphagnum regeneration (>10% cover) were strongly correlated with high water tables (mean -22 cm), especially in zones of seasonal groundwater discharge, artefacts of the extraction history. Forest cover expanded from 5 to 20% of the study area following abandonment. The effect of forest growth (transpiration and interception) and drainage on lowering water levels eventually will be countered by slower water movement through the

  8. Effects of environmental and anthropogenic determinants on changes in groundwater levels in selected peat bogs of Slowinski National Park, northern Poland

    Science.gov (United States)

    Chlost, Izabela; Cieśliński, Roman

    2018-03-01

    The present study focuses on two Baltic-type peat bogs in Slowinski National Park, namely that at Żarnowskie and at Kluki, located in the Lake Łebsko catchment and both characterised by a centrally located dome with a very marshy fringe area featuring an emerging marshy coniferous forest (Vaccinio uliginosi-Pinetum). The Żarnowskie bog is under active protection. A total of 24 flow barriers were installed in drainage ditches during the years 2006 and 2007. The purpose of these barriers was to put a halt to water outflow. In addition, 30 hectares of young pine forest were cleared in order to decrease loss of water via evapotranspiration. Kluki peat bog is only partially protected by Polish law. The lack of efforts to prevent outflow via the canal is due to the fact that the canal is utilised to drain meadows in the vicinity of the village of Łokciowe outside of the national park. Peat formation no longer occurs in this peat bog. The hydrological condition of the bog is catastrophic as a result of its main canal, referred to as Canal C9, which is 2.5 to 3.0 m deep and 10 m wide in places. Both peat bogs are monitored for fluctuations in groundwater. Research has shown that changes in water levels fluctuate based on season of the year and geographical location, which is illustrated quite well using the two studied peat bogs. The water retention rate of the Żarnowskie peat bog may be considered fairly high and is likely to improve due to protective measures enabled by Polish environmental laws. The water retention rate of the bog is consistently improving thanks to these measures, fluctuations in water level are small and the water level does not drop under 0.5 m below ground level even under extreme hydrometeorological conditions. This yields optimum conditions for renewed peat formation in this area. One potential threat is the Krakulice peat extraction facility, which is located in the southern part of the bog close to the boundary with the national park.

  9. Boil off gas (BOG) management in Spanish liquid natural gas (LNG) terminals

    Energy Technology Data Exchange (ETDEWEB)

    Querol, E.; Gonzalez-Regueral, B.; Garcia-Torrent, J.; Garcia-Martinez, M.J. [Departamento de Ingenieria Quimica y Combustibles, Escuela Tecnica Superior de Ingenieros de Minas, Universidad Politecnica de Madrid, c. Alenza 4, 28003 Madrid (Spain)

    2010-11-15

    Spain is a country with six LNG terminals in operation and three more scheduled for 2011. At the same time an increasing number of LNG tanks are under construction to compensate the Spanish lack of underground storage. A method for evaluating the daily boil off generated is presented in this paper. This method is applied to evaluate the increase of BOG to be handle by LNG terminals in 2016, studying the best commercially available solution to be installed. Finally, as a solution to tackle with the BOG a cogeneration plant is suggested. This option will reduce terminal's operational costs increasing its availability. (author)

  10. Indicative effects of climate change on groundwater levels in Estonian raised bogs over 50 years

    Directory of Open Access Journals (Sweden)

    E. Lode

    2017-08-01

    Full Text Available Analyses of 50-year (1962–2011 monthly air temperature and precipitation data indicated substantial climate change in the locations of two raised bogs (Linnusaare and Männikjärve in central-east Estonia. During recent years the cross-year winter air temperature increased by 1.7 ºC, while the cold-season precipitation increased by 4 mm. The fluctuation amplitude of temperature and precipitation values decreased. Snow depth proved to be the most sensitive variable to winter warming, followed by groundwater levels together with mean and maximum soil frosts. Long-term groundwater levels on the domes of the bogs and in the forested/treed lagg areas were 0.3−0.4 m and 0.4−0.8 m below the soil surface, respectively. Warming caused changes in groundwater level amplitude of 3−22 cm in the bog domes and 3−14 cm in the forested lagg zones. The lowest groundwater levels in ridge-pool ecotopes at Männikjärve rose by 6−10 cm (i.e. these ecotopes became wetter; but the incidence of low groundwater levels increased in most ecotopes, indicating a more general trend towards drier conditions in the bog.

  11. Tracing decadal environmental change in ombrotrophic bogs using diatoms from herbarium collections and transfer functions

    International Nuclear Information System (INIS)

    Poulíčková, Aloisie; Hájková, Petra; Kintrová, Kateřina; Bat'ková, Romana; Czudková, Markéta; Hájek, Michal

    2013-01-01

    Central European mountain bogs, among the most valuable and threatened of habitats, were exposed to intensive human impact during the 20th century. We reconstructed the subrecent water chemistry and water-table depths using diatom based transfer functions calibrated from modern sampling. Herbarium Sphagnum specimens collected during the period 1918–1998 were used as a source of historic diatom samples. We classified samples into hummocks and hollows according to the identity of dominant Sphagnum species, to reduce bias caused by uneven sampling of particular microhabitats. Our results provide clear evidence for bog pollution by grazing during the period 1918–1947 and by undocumented aerial liming in the early 90-ies. We advocate use of herbarized epibryon as a source of information on subrecent conditions in recently polluted mires. -- Highlights: •We reconstruct the subrecent ecological variables using transfer functions. •Calibration was based on long-term averages and modern diatom sampling. •Herbarized bryophytes were used as a source of historic diatom samples. •Bogs were influenced by grazing in the period 1918–1947. •We provide clear evidence of bog pollution by aerial liming in early 90-ies. -- We provide clear evidence that the recent pH/calcium gradient appeared ca 20 years ago owing to aerial liming of forests

  12. Sphagnum farming on cut-over bog in NW Germany: Long-term studies on Sphagnum growth

    OpenAIRE

    G. Gaudig; M. Krebs; H. Joosten

    2017-01-01

    Sphagnum farming allows sustainable and climate-friendly land use on bogs while producing a renewable substitute for peat in horticultural growing media. We studied Sphagnum productivity on an experimental Sphagnum culture established on a cut-over bog in Germany with strongly humified peat at the surface. Preparation of the site included levelling of the peat surface, construction of an irrigation system, spreading of Sphagnum papillosum fragments, covering them with straw, and finally rewet...

  13. Optimization of UA of heat exchangers and BOG compressor exit pressure of LNG boil-off gas reliquefaction system using exergy analysis

    Science.gov (United States)

    Kochunni, Sarun Kumar; Ghosh, Parthasarathi; Chowdhury, Kanchan

    2015-12-01

    Boil-off gas (BOG) generation and its handling are important issues in Liquefied natural gas (LNG) value chain because of economic, environment and safety reasons. Several variants of reliquefaction systems of BOG have been proposed by researchers. Thermodynamic analyses help to configure them and size their components for improving performance. In this paper, exergy analysis of reliquefaction system based on nitrogen-driven reverse Brayton cycle is carried out through simulation using Aspen Hysys 8.6®, a process simulator and the effects of heat exchanger size with and without related pressure drop and BOG compressor exit pressure are evaluated. Nondimensionalization of parameters with respect to the BOG load allows one to scale up or down the design. The process heat exchanger (PHX) requires much higher surface area than that of BOG condenser and it helps to reduce the quantity of methane vented out to atmosphere. As pressure drop destroys exergy, optimum UA of PHX decreases for highest system performance if pressure drop is taken into account. Again, for fixed sizes of heat exchangers, as there is a range of discharge pressures of BOG compressor at which the loss of methane in vent minimizes, the designer should consider choosing the pressure at lower value.

  14. Peat decomposition records in three pristine ombrotrophic bogs in southern Patagonia

    Directory of Open Access Journals (Sweden)

    T. Broder

    2012-04-01

    Full Text Available Ombrotrophic bogs in southern Patagonia have been examined with regard to paleoclimatic and geochemical research questions but knowledge about organic matter decomposition in these bogs is limited. Therefore, we examined peat humification with depth by Fourier Transformed Infrared (FTIR measurements of solid peat, C/N ratio, and δ13C and δ15N isotope measurements in three bog sites. Peat decomposition generally increased with depth but distinct small scale variation occurred, reflecting fluctuations in factors controlling decomposition. C/N ratios varied mostly between 40 and 120 and were significantly correlated (R2 > 0.55, p < 0.01 with FTIR-derived humification indices. The degree of decomposition was lowest at a site presently dominated by Sphagnum mosses. The peat was most strongly decomposed at the driest site, where currently peat-forming vegetation produced less refractory organic material, possibly due to fertilizing effects of high sea spray deposition. Decomposition of peat was also advanced near ash layers, suggesting a stimulation of decomposition by ash deposition. Values of δ13C were 26.5 ± 2‰ in the peat and partly related to decomposition indices, while δ15N in the peat varied around zero and did not consistently relate to any decomposition index. Concentrations of DOM partly related to C/N ratios, partly to FTIR derived indices. They were not conclusively linked to the decomposition degree of the peat. DOM was enriched in 13C and in 15N relative to the solid phase probably due to multiple microbial modifications and recycling of N in these N-poor environments. In summary, the depth profiles of C/N ratios, δ13C values, and FTIR spectra seemed to reflect changes in environmental conditions affecting decomposition, such as bog wetness, but were dominated by site specific factors, and are further influenced by ash

  15. Contribution to the development of peat-bog and history of landscape in the Havellaendische Luch

    International Nuclear Information System (INIS)

    Mundel, G.; Trettin, R.; Hiller, A.

    1983-01-01

    By means of the 14 C method a low-bog profile of the Havellaendische Luch measuring 200 cm in depth was dated systematically. The peat formation had started as early as at the end of the late-glacial. Approximately 6000 years ago a stagnation of bog growth had occured and then about 3700 years ago a stronger bog growth had begun again. The change in peat components and thereby in the geological structure is largely attributed to different ground water levels. According to the relatively low total thickness the annual mean rates of accumulation are small. In muddy soils, values between 0.2 and 1.2 mm were ascertained. In peat soils these values are still smaller. But here it is a question of remainders of the protogenic peat formation. As a result of former or recent mineralization the original peat substance has been diminished. (author)

  16. 76 FR 77814 - Cameron LNG, LLC; Notice of Intent To Prepare an Environmental Assessment for the Proposed BOG...

    Science.gov (United States)

    2011-12-14

    .... Summary of the Proposed Project Cameron LNG plans to construct and operate facilities necessary to liquefy boil-off gas (BOG) at its existing liquefied natural gas (LNG) terminal in Cameron Parish, Louisiana... sufficient LNG in each of the terminal's storage tanks. Currently, BOG is sent out via delivery into the...

  17. Greenhouse gas balance of an establishing Sphagnum culture on a former bog grassland in Germany

    OpenAIRE

    A. Günther; G. Jurasinski; K. Albrecht; G. Gaudig; M. Krebs; S. Glatzel

    2017-01-01

    The cultivation of Sphagnum mosses on re-wetted peat bogs for use in horticulture is a new land use strategy. We provide the first greenhouse gas balances for a field-scale Sphagnum farming experiment on former bog grassland, in its establishment phase. Over two years we used closed chambers to make measurements of GHG exchange on production strips of Sphagnum palustre L. and Sphagnum papillosum Lindb. and on irrigation ditches. Methane fluxes of both Sphagnum species showed a significant dec...

  18. High-resolution records of late-Holocene climate change and carbon accumulation in two north-west European ombrotrophic peat bogs

    NARCIS (Netherlands)

    Mauquoy, D; Engelkes, T; Groot, MHM; Markesteijn, F; Oudejans, MG; van der Plicht, J; van Geel, B

    2002-01-01

    The peat stratigraphy (plant macrofossils, colorimetric humification, pollen/non-pollen microfossils, carbon/nitrogen ratios) of three replicate cores from a raised peat bog in the UK (Walton Moss) and a single core from a raised peat bog in Denmark (Lille Vildmose) were examined in an attempt to

  19. AHP 40: SOCIALIZING WITH GODS IN THE MONGGHUL BOG RITUAL

    Directory of Open Access Journals (Sweden)

    Limusishiden (Li Dechun

    2016-02-01

    Full Text Available This article introduces a communal ritual, known as Bog, as practiced among the Mongghul, a linguistically and culturally distinct group of people of the northeast Tibetan Plateau. The main activity of the Bog ritual involves deities and ancestral souls being invited to a sumptuous "banquet" where religious practitioners, called fashi, chant scriptures, sing, dance, joke, and burn incense to delight the "guests." This essay provides a thick description of the ritual. To provide context for this description, we introduce the community on which our description focuses, and also discuss the role of fashi. A chronological account of the ritual follows that includes not only descriptions of the ritual activities, but also interpretations of the meaning of these events from the perspective of the ritual practitioners. We also provide an analysis of the performances given during the ritual and how they contribute to creating a spectacle that delights both human and non-human participants.

  20. Genesis of Spodic Material underneath Peat Bogs in a Danish Wetland

    DEFF Research Database (Denmark)

    Kristiansen, Søren Munch; Dalsgaard, Kristian; Thomsen, Ingrid Kaag

    2010-01-01

    illuviation under a fluctuating water table, or (ii) degradation of a former Fe-rich, well-drained spodic horizon. Methods included soil surveys, wet chemical analyses, micromorphology, pollen analysis, and radiocarbon dating of soil organic matter (OM) fractions. Aquods, and soil material with spodic...... features, were exclusively found in sandy material at the margins of or underneath sphagnum peat bogs, whereas Inceptisols were found on well-drained sandy deposits only. Aluminum content was very high and Fe low in spodic materials with ortstein properties. Solid-state 13C nuclear magnetic resonance (NMR....... Radiocarbon ages of bulk soil C in the spodic horizons had mean residence times of 4500 to 4400 yr. Accordingly, the spodic B horizon was probably formed by strong in situ illuviation of Al-OM complexes before the sphagnum peat bog formation. This suggests that spodic material formation and thus strong C...

  1. Dicranochaete quadriseta (Korš. Nov. and Pop. from an oligominerotrophic peat bog in Lower Silesia (South-Western Poland

    Directory of Open Access Journals (Sweden)

    Jan Matuła

    2011-01-01

    Full Text Available Dicranochaete quadriseta (Korš. Nov. and Pop. was collected during investigations of algae from mountain peat bogs of the Sudeten Mts (Poland. The paper describes the morphology, taxanomy, geographical distribution and ecological conditions of this species. This very rare species was found in an oligominerotrophic peat bog called "Topieliska-Zieleniec" near Duszniki (Orlickie Mts.

  2. Ecology of Coom Rigg Moss, Northumberland. II. The chemistry of peat profiles and the development of the bog system

    Energy Technology Data Exchange (ETDEWEB)

    Chapman, S B

    1964-01-01

    Chemical analyses of peat profiles are described. They demonstrate changes in peat composition at the different stages in the bog's development from the minerotrophic conditions under which fen peat was formed to ombrotrophic conditions under which sphagnum-eriophorum peat was formed. The peats of the eastern sector of the bog are shown to have been minerotrophic until a comparatively late stage in the bog's development due to the surrounding topography allowing phragmites to persist even till the present day. Increased silica and aluminum in the upper peat layers are discussed in terms of increased deposition brought about by the activities of man through deforestation and the production of open habitats.

  3. Ground-penetrating radar study of the Cena Bog, Latvia: linkage of reflections with peat moisture content

    Directory of Open Access Journals (Sweden)

    Karušs, J.

    2015-12-01

    Full Text Available Present work illustrates results of the ground-penetrating radar (GPR study of the Cena Bog, Latvia. Six sub-horizontal reflections that most probably correspond to boundaries between sediments with different electromagnetic properties were identified. One of the reflections corresponds to bog peat mineral bottom interface but the rest are linked to boundaries within the peat body. The radar profiles are incorporated with sediment cores and studies of peat moisture and ash content, and degree of decomposition. Most of the electromagnetic wave reflections are related to changes in peat moisture content. The obtained data show that peat moisture content changes of at least 3 % are required to cause GPR signal reflection. However, there exist reflections that do not correlate with peat moisture content. As a result, authors disagree with a dominant opinion that all reflections in bogs are solely due to changes in volumetric peat moisture content.

  4. Anmeldelse: Peter Gøtzsches nye bog: Big pharma = Big crime?

    DEFF Research Database (Denmark)

    Møller, Marianne

    2013-01-01

    Cochrane-lægen Peter Gøtzsche har udgivet en bog med stærk kritik af medicinalindustrien og systemet for godkendelse og kontrol af medicin. Bogen er ladet med eksempler fra mange terapeutiske områder og er - med sin usædvanligt hårde retorik - en oplagt debatskaber....

  5. Reintroduction of salt marsh vegetation and phosphorus fertilisation improve plant colonisation on seawater-contaminated cutover bogs

    Directory of Open Access Journals (Sweden)

    C. Emond

    2016-07-01

    Full Text Available Coastal bogs that are used for peat extraction are prone to contamination by seawater during storm events. Once contaminated, they remain mostly bare because of the combination of high salinity, low pH, high water table and low nutrient availability. The goal of this research was to investigate how plant colonisation at salt-contaminated bogs can be accelerated, in order to prevent erosion and fluvial export of the peat. At two seawater-contaminated bogs, we tested the application of rock phosphate and dolomitic lime in combination with five plant introduction treatments: transplantation of Carex paleacea; transplantation of Spartina pectinata; transfer of salt marsh diaspores in July; transfer of salt marsh diaspores in August; and no treatment (control. The effects of different doses of lime on the growth of C. paleacea and S. pectinata were also investigated in a greenhouse experiment. In the field, phosphorus fertilisation improved plant growth. Transplantation of C. paleacea resulted in the highest plant colonisation, whereas salt marsh diaspore transfer led to the highest species diversity. Lime applications did not improve plant establishment in either the field or the greenhouse. To promote revegetation of seawater-contaminated cutover bogs, adding P is an asset, Carex paleacea is a good species to transplant, and the transfer of salt marsh diaspores improves plant diversity.

  6. Iodine dispersion and effects on groundwater chemistry following a release to a peat bog, Manitoba, Canada

    International Nuclear Information System (INIS)

    Sheppard, M.I.; Thibault, D.H.; Smith, P.A.

    1989-01-01

    The migration and behaviour of I was investigated in a sphagnum bog on the precambrian Shield in eastern Manitoba, Canada. A 6 M solution of K1 was released at the base of the bog to simulate a pulse discharge of contaminated groundwater from a fracture in the granitic rock. A network of piezometer tubes was used to monitor the dispersion of the I and the groundwater chemistry over 1 year. Cores of peat were also taken for analysis to supplement the groundwater data and to investigate the sorption of I. The introduced I dispersed 2 m horizontally and 1 m vertically within a month. After this, the system stabilized and further migration was insignificant. The pattern of I dispersion indicated that the bog hydrology was very complex with flow directions changing substantially with depth. The groundwater concentrations of the major cations rose in response to the mass action effect of K displacing them from reaction sites in the peat. Humic materials in the groundwater decreased in size after the KI release and returned to their pre-release conformation one month later. The geometric mean soil distribution coefficient value, K d , for I in the bog was 1.361/kg, but it was strongly related to pore water concentration. Thus, a single K d value was insufficient for describing the system. (author)

  7. Ferricrete, manganocrete, and bog iron occurrences with selected sedge bogs and active iron bogs and springs in the upper Animas River watershed, San Juan County, Colorado

    Science.gov (United States)

    Yager, Douglas B.; Church, Stan E.; Verplanck, Philip L.; Wirt, Laurie

    2003-01-01

    During 1996 to 2000, the Bureau of Land Management, National Park Service, Environmental Protection Agency, United States Department of Agriculture (USDA) Forest Service, and the U.S. Geological Survey (USGS) developed a coordinated strategy to (1) study the environmental effects of historical mining on Federal lands, and (2) remediate contaminated sites that have the greatest impact on water quality and ecosystem health. This dataset provides information that contributes to these overall objectives and is part of the USGS Abandoned Mine Lands Initiative. Data presented here represent ferricrete occurrences and selected iron bogs and springs in the upper Animas River watershed in San Juan County near Silverton, Colorado. Ferricretes (stratified iron and manganese oxyhydroxide-cemented sedimentary deposits) are one indicator of the geochemical baseline conditions as well as the effect that weathering of mineralized rocks had on water quality in the Animas River watershed prior to mining. Logs and wood fragments preserved in several ferricretes in the upper Animas River watershed, collected primarily along streams, yield radiocarbon ages of modern to 9,580 years B.P. (P.L. Verplanck, D.B. Yager, and S.E. Church, work in progress). The presence of ferricrete deposits along the current stream courses indicates that climate and physiography of the Animas River watershed have been relatively constant throughout the Holocene and that weathering processes have been ongoing for thousands of years prior to historical mining activities. Thus, by knowing where ferricrete is preserved in the watershed today, land-management agencies have an indication of (1) where metal precipitation from weathering of altered rocks has occurred in the past, and (2) where this process is ongoing and may confound remediation efforts. These data are included as two coverages-a ferricrete coverage and a bogs and springs coverage. The coverages are included in ArcInfo shapefile and Arc

  8. Pattern of large raised bog formation in the South-Eastern Baltic Region during the Holocene: the case of Kaliningrad oblast

    Science.gov (United States)

    Napreenko-Dorokhova, T. V.; Napreenko, M. G.; Lisitzin, A. P.

    2017-08-01

    The results of complex investigations that have been carried out since 2007 in large bog ecosystems (Zehlau, Bolshoe Mokhovoe, and Koz'e) located in Kaliningrad oblast in two largest landscape areas, glaciolacustrine plains in the central part of the region and coastal lowlands of the southern coast of Curonian Lagoon and the delta of the Neman River, are presented. It is established that the intensive development of mires and their transition to the raised bog stage occurred in the territory of Kaliningrad oblast later than in most of the forest zone in European Russia, where this process was noted as early as during the Atlantic. On the glaciolacustrine flat plains in the central part of Kaliningrad oblast, where there were no deep depressions, the mire formation process was manifested weakly for a long time. A colder and more humid climate, which is a condition necessary for the raised bog peat accumulation and rapid expansion of bogs to the adjacent forest area, occurred only in the Subatlantic.

  9. Fra bog til film

    DEFF Research Database (Denmark)

    Schepelern, Peter

    2010-01-01

    Efter en historisk oversigt over samspillet mellem film og litteratur i dansk film, opstilles en råkke begreber, som filmatiseringer kan analyseres ud fra. Der ses pa det litteråre vårks status — evt. som klassiker eller bestseller. Der ses pa de centrale filmatiseringsproblemer, forhold som pråger...... adaptionsprocessen fra bog til film. De kan opdeles dels i forhold, der udspringer af filmsprogets specifikke sys- tem, dels forhold, der udspringer af filmens status som massemedium. Den färste kategori er pråget af, at filmsproget generelt fremstiller handling snarere end refleksion, noget konkret snarere end...... noget abstrakt, en scene snarere end et resume og det ydre snarere det indre. Den anden kategori kan forklare filmens tilbäjelighed til åndring af forlågget, til forkortelse, forenkling og modernisering. Eksemplerne er en råkke centrale danske film/romaner...

  10. Boreal bog plants: nitrogen sources and uptake of recently deposited nitrogen

    International Nuclear Information System (INIS)

    Nordbakken, J.F.; Ohlson, M.; Hoegberg, P.

    2003-01-01

    The main goals of this study were to determine the δ 15 N signature of quantitatively important boreal bog plants as basis for discussing their N sources, and to assess the effects of five different 3 year N treatments (i.e. 0, 5, 10, 20 and 40 kg N ha -1 year -1 ) on the bog plants and surface peat at different depths (i.e. 0, 5, 10, 20 and 40 cm) by using 15 N as tracer. Plants and peat were analyzed for N concentration, 15 N natural abundance and 15 N at.%. From the results we draw three main conclusions: First, the relative importance of different N sources is species-specific among bog plants. Second, an annual addition of 5 kg N ha -1 year -1 was sufficient to significantly increase the N concentration in Sphagnum mosses, liverworts and shallow rooted vascular plants, and an annual addition of 40 kg N ha -1 year -1 during 3 years was not sufficient to increase the N concentration in deep rooted plants, although the 15 N content increased continuously, indicating a possible longer term effect. Third, an annual addition of 40 kg N ha -1 year -1 during 3 years increased the N content in surface peat at depths of 5 and 10 cm, but not at depths of 20 and 40 cm, indicating the capacity of the living Sphagnum mosses and the surface peat to take up deposited N, and thereby function as a filter. - Living Sphagnum mosses and surface peat function as a filter for added nitrogen

  11. Distribution of 35 Elements in Peat Cores from Ombrotrophic Bogs Studied by Epithermal Neutron Activation Analysis

    CERN Document Server

    Frontasyeva, M V

    2004-01-01

    In ombrotrophic bogs the surface peat layer is supplied with chemical substances only from the atmosphere. Peat cores from these bogs therefore can be used to study temporal trends in atmospheric deposition of pollutants. In this work epithermal neutron activation analysis was applied for the first time to study the distribution of 35 elements in peat profiles from ombrotrophic bogs. The selected examples were from Finnmark county in northern Norway: one pristine site far from any local pollution source, and another strongly affected by long-term operation of Russian copper-nickel smelters located close to the border. The elements are classified with respect to their behavior in the uppermost 40 cm of the peat, and similarities and differences between the two profiles are discussed. As compared with other more commonly used analytical techniques based on acid decomposition of the sample ENAA has the advantage of providing the total concentrations of the elements.

  12. IMPACTS OF ECOTOURISM ON THE BOG OF SERRA NEGRA - BEZERROS/ PE

    Directory of Open Access Journals (Sweden)

    Carolina Florio Castro

    2005-05-01

    Full Text Available The “Brejo da Serra Negra” ( Bog of Serra Negra has become an area of interest of manysectors of society, among them tourism in its different forms. Ecotourism is one of thepropellers of tourism and defined by the Institute of Ecotourism of Brazil as : “the practice ofrecreational, sporting or educational tourism using, in a sustainable form, natural and culturalassets, encouraging conservation, promoting environmental awareness and assuring the wellbeing of the populations involved” (Instituto de Ecoturismo do Brasil, 1995. Within thisperspective some questions such as : how does ecotourism is developed in the concernedarea? What are the impacts caused on Brejo da Serra Negra ( Bog of Serra Negra? How isenvironmental awareness being addressed? should be answered.The Brejo da Serra Negra has been the constant aim of ecotourism because of its very uniquebeauty and the fact that it is a climatic sub-humid area in the hinterlands of Pernambuco andattraction to the so-called radical sports, ecologic tours, caverns exploring as well as camping.

  13. Methane fluxes during the cold season: distribution and mass transfer in the snow cover of bogs

    Science.gov (United States)

    Smagin, A. V.; Shnyrev, N. A.

    2015-08-01

    Fluxes and profile distribution of methane in the snow cover and different landscape elements of an oligotrophic West-Siberian bog (Mukhrino Research Station, Khanty-Mansiisk autonomous district) have been studied during a cold season. Simple models have been proposed for the description of methane distribution in the inert snow layer, which combine the transport of the gas and a source of constant intensity on the soil surface. The formation rates of stationary methane profiles in the snow cover have been estimated (characteristic time of 24 h). Theoretical equations have been derived for the calculation of small emission fluxes from bogs to the atmosphere on the basis of the stationary profile distribution parameters, the snow porosity, and the effective methane diffusion coefficient in the snow layer. The calculated values of methane emission significantly (by 2-3 to several tens of times) have exceeded the values measured under field conditions by the closed chamber method (0.008-0.25 mg C/(m2 h)), which indicates the possibility of underestimating the contribution of the cold period to the annual emission cycle of bog methane.

  14. Spatial and temporal performance of the miniface (free air CO2 enrichment) system on bog ecosystems in northern and central Europe

    NARCIS (Netherlands)

    Miglietta, F.; Hoosbeek, M.R.; Foot, J.; Gigon, F.; Hassinen, A.; Heijmans, M.; Peressotti, A.; Saarinen, T.; Breemen, van N.; Wallen, B.

    2001-01-01

    The Bog Ecosystem Research Initiative (BERI) project was initiated to investigate, at five climatically different sites across Europe, the effects of elevated CO2 and N deposition on the net exchange of CO2 and CH4 between bogs and the atmosphere, and to study the effects of elevated CO2 and N

  15. Biogeochemistry of carbon and related major and trace elements in peat bog soils of the middle taiga of Western Siberia (Russia).

    Science.gov (United States)

    Stepanova, V. A.; Mironycheva-Tokareva, N. P.; Pokrovsky, O. S.

    2012-04-01

    Global climate changes impact the status of wetland ecosystems shifting the balances of the carbon, macro-, and microelements cycles. This study aims to establish the features of accumulation and distribution of major- and trace elements in the organic layer of peat bog soils, belonging to different ecosystems of the oligotrophic bog complex located in the middle taiga of Western Siberia (Khanty-Mansiysk region, Russia). Key areas which are selected for this study include the following bog conjugate elementary ecosystems: higher ryam, lower ryam, ridge-hollow complex, and oligotrophic poor fen as characterized previously [1]. We have sampled various peat types along the entire length of the soil column (every 10 cm down to 3 m). Peat samples were analyzed for a wide range of macro- and microelements using an ICP-MS technique following full acid digestion in a microwave oven. These measurements allowed quantitative estimates of major- and trace elements in the peat deposits within the whole bog complex and individual elementary landscapes. Based on the data obtained, the lateral and radial geochemical structures of the bog landscapes were determined and clarified for the first time for middle taiga of the West Siberian plain. The similar regime of mineral nutrition during the complete bog landscape formation was detected for the peat deposits based on the measurements of some major- and trace elements (Ca, Fe, Mg, etc.). The vertical distribution of some major and some trace elements along the profile of peat column is rather uniform with relatively strong increase in the bottom organic layers. This strongly suggests the similarity of the processes of element accumulation in the peat and relatively weak post depositional redistribution of elements within the peat soil profile. Overall, obtained corroborate the existing view on chemical composition of peats being determined by botanical peat's components (which forms this peat deposit), atmospheric precipitation

  16. Annual greenhouse gas budget for a bog ecosystem undergoing restoration by rewetting

    Science.gov (United States)

    Lee, Sung-Ching; Christen, Andreas; Black, Andrew T.; Johnson, Mark S.; Jassal, Rachhpal S.; Ketler, Rick; Nesic, Zoran; Merkens, Markus

    2017-06-01

    Many peatlands have been drained and harvested for peat mining, agriculture, and other purposes, which has turned them from carbon (C) sinks into C emitters. Rewetting of disturbed peatlands facilitates their ecological recovery and may help them revert to carbon dioxide (CO2) sinks. However, rewetting may also cause substantial emissions of the more potent greenhouse gas (GHG) methane (CH4). Our knowledge of the exchange of CO2 and CH4 following rewetting during restoration of disturbed peatlands is currently limited. This study quantifies annual fluxes of CO2 and CH4 in a disturbed and rewetted area located in the Burns Bog Ecological Conservancy Area in Delta, BC, Canada. Burns Bog is recognized as the largest raised bog ecosystem on North America's west coast. Burns Bog was substantially reduced in size and degraded by peat mining and agriculture. Since 2005, the bog has been declared a conservancy area, with restoration efforts focusing on rewetting disturbed ecosystems to recover Sphagnum and suppress fires. Using the eddy covariance (EC) technique, we measured year-round (16 June 2015 to 15 June 2016) turbulent fluxes of CO2 and CH4 from a tower platform in an area rewetted for the last 8 years. The study area, dominated by sedges and Sphagnum, experienced a varying water table position that ranged between 7.7 (inundation) and -26.5 cm from the surface during the study year. The annual CO2 budget of the rewetted area was -179 ± 26.2 g CO2-C m-2 yr-1 (CO2 sink) and the annual CH4 budget was 17 ± 1.0 g CH4-C m-2 yr-1 (CH4 source). Gross ecosystem productivity (GEP) exceeded ecosystem respiration (Re) during summer months (June-August), causing a net CO2 uptake. In summer, high CH4 emissions (121 mg CH4-C m-2 day-1) were measured. In winter (December-February), while roughly equal magnitudes of GEP and Re made the study area CO2 neutral, very low CH4 emissions (9 mg CH4-C m-2 day-1) were observed. The key environmental factors controlling the seasonality of

  17. Greenhouse gas balance of an establishing Sphagnum culture on a former bog grassland in Germany

    Directory of Open Access Journals (Sweden)

    A. Günther

    2017-04-01

    Full Text Available The cultivation of Sphagnum mosses on re-wetted peat bogs for use in horticulture is a new land use strategy. We provide the first greenhouse gas balances for a field-scale Sphagnum farming experiment on former bog grassland, in its establishment phase. Over two years we used closed chambers to make measurements of GHG exchange on production strips of Sphagnum palustre L. and Sphagnum papillosum Lindb. and on irrigation ditches. Methane fluxes of both Sphagnum species showed a significant decrease over the study period. This trend was stronger for S. papillosum. In contrast, the estimated CO2 fluxes did not show a significant temporal trend over the study period. The production strips of both Sphagnum species were net GHG sinks of 5–9 t ha 1 a 1 (in CO2-equivalents during the establishment phase of the moss carpets. In comparison, the ditches were a CO2 source instead of a CO2 sink and emitted larger amounts of CH4, resulting in net GHG release of ~11 t ha 1 a 1 CO2-equivalents. We conclude that Sphagnum farming fields should be designed to minimise the area covered by irrigation ditches. Overall, Sphagnum farming on bogs has lower on-field GHG emissions than low-intensity agriculture.

  18. Preliminary stable isotope results from the Mohos peat bog, East-Carpathians

    Science.gov (United States)

    Túri, Marianna; Palcsu, László; Futó, István; Hubay, Katalin; Molnár, Mihály; Rinyu, László; Braun, Mihály

    2016-04-01

    This work provides preliminary results of an isotope investigation carried out on a peat core drilled in the ombrotrophic Mohos peat bog, Ciomadul Mountain, (46°8'3.60"N, 25°54'19.43"E, 1050 m.a.s.l.), East Carpathians, Romania. The Ciomadul is a single dacitic volcano with two craters: the younger Saint Ana and the older Mohos which is a peat bog, and surrounded by a number of individual lava domes as well as a narrow volcaniclastic ring plain volcano. A 10 m long peat core has been taken previously, and is available for stable oxygen and carbon isotope analysis. It is known from our previous work (Hubay et al., 2015) that it covers a period from 11.500 cal year B.P. to present. The peat bog is composed mainly of Sphagnum, which has a direct relationship with the environment, making it suitable for examine the changes in the surrounding circumstances. Isotopic analysis of the prepared cellulose from Sphagnum moss has the attribute to provide such high resolution quantitative estimates of the past climate and there is no such climate studies in this area where the past climate investigations based on oxygen isotope analysis of the Sphagnum. Oxygen and carbon stable isotope analysis were carried out on the hemicellulose samples, which were chemically prepared for 14C dating and taken from every 30 cm of the 10 m long peat core. The oxygen isotope composition of the precipitation can be revealed from the δ18O values of the prepared cellulose samples, since, while carbon isotope ratio tells more about the wet and dry periods of the past. Studying both oxygen and carbon isotope signatures, slight fluctuations can be seen during the Holocene like some of the six periods of significant climate changes can be seen in this resolution during the time periods of 9000-8000, 6000-5000, 4200-3800, 3500-2500, 1200-1000, and 600-150 cal yr B.P. Additionally, the late Pleistocene - early Holocene environmental changes can be clearly observed as Pleistocene peat samples have

  19. Some Late-Holocene pollen diagrams from the Peel raised bogs (Southern Netherlands)

    NARCIS (Netherlands)

    Janssen, C.R.; Hove, ten H.A.

    1971-01-01

    Three pollen diagrams from the Peel peatlands, a raised bog area in the southern part of The Netherlands reveal the post-Boreal vegetation history of that region. There are two or three land-occupation phases in the Neolithic and Bronze ages, that show but low values of terrestrial herbs. They are

  20. Metabolism of nonparticulate phosphorus in an acid bog lake

    International Nuclear Information System (INIS)

    Koenings, J.P.

    1977-01-01

    In North Gate Lake, an acid bog lake located on the northern Michigan-Wisconsin border, U.S.A., the algal nutrient inorganic phosphate (FRP) is not detectable by chemical means. Organic phosphorus (FUP) represents 100% of the detectable filterable phosphorus. The availability and cycling of this organic fraction are of considerable interest in regard to the primary productivity of this system. To clarify these relationships, the cycling of nonparticulate forms of phosphorus found in the epilimnion of this lake was studied

  1. Metabolism of nonparticulate phosphorus in an acid bog lake

    Energy Technology Data Exchange (ETDEWEB)

    Koenings, J. P.

    1977-01-01

    In North Gate Lake, an acid bog lake located on the northern Michigan-Wisconsin border, U.S.A., the algal nutrient inorganic phosphate (FRP) is not detectable by chemical means. Organic phosphorus (FUP) represents 100% of the detectable filterable phosphorus. The availability and cycling of this organic fraction are of considerable interest in regard to the primary productivity of this system. To clarify these relationships, the cycling of nonparticulate forms of phosphorus found in the epilimnion of this lake was studied.

  2. Biological N2 fixation mainly controlled by Sphagnum tissue N:P ratio in ombrotrophic bogs

    Science.gov (United States)

    Zivkovic, Tatjana; Moore, Tim R.

    2017-04-01

    Most of the 18 Pg nitrogen (N) accumulated in northern nutrient-poor and Sphagnum-dominated peatlands (bogs and fens) can be attributed to N2-fixation by diazotrophs either associated with the live Sphagnum or non-symbiotically in the deeper peat such as through methane consumption close to the water table. Where atmospheric N deposition is low (Sphagnum, suggested by the increase in tissue N:P to >16. It is unclear how Sphagnum-hosted diazotrophic activity may be affected by N deposition and thus changes in N:P ratio. First, we investigated the effects of long-term addition of different sources of nitrogen (0, 1.6, 3.2 and 6.4 g N m-2 y-1as NH4Cl and NaNO3), and phosphorus (5 g P m-2 y-1as KH2PO4) on Sphagnum nutrient status (N, P and N:P ratio), net primary productivity (NPP) and Sphagnum-associated N2fixation at Mer Bleue, a temperate ombrotrophic bog. We show that N concentration in Sphagnum tissue increased with larger rates of N addition, with a stronger effect on Sphagnum from NH4 than NO3. The addition of P created a 3.5 fold increase in Sphagnum P content compared to controls. Sphagnum NPP decreased linearly with the rise in N:P ratio, while linear growth declined exponentially with increase in Sphagnum N content. Rates of N2-fixation determined in the laboratory significantly decreased in response to even the smallest addition of both N species. In contrast, the addition of P increased N2 fixation by up to 100 times compared to N treatments and up to 5-30 times compared to controls. The change in N2-fixation was best modeled by the N:P ratio, across all experimental treatments. Secondly, to test the role of N:P ratio on N2-fixation across a range of bogs, eight study sites along the latitudinal gradient from temperate, boreal to subarctic zone in eastern Canada were selected. From each bog, two predominant microptopographies, hummocks and hollows, were tested for both N2-fixation activity in the laboratory and Sphagnum tissue concentrations of N, P and N

  3. Dendrochronologically dated pine stumps document phase-wise bog expansion at a northwest German site between ca. 6700 and ca. 3400 BC

    Science.gov (United States)

    Maike Achterberg, Inke Elisabeth; Eckstein, Jan; Birkholz, Bernhard; Bauerochse, Andreas; Leuschner, Hanns Hubert

    2018-01-01

    The investigated northwest German mire site at Totes Moor is densely covered with subfossil pine stumps (Pinus sylvestris L.) from the fen-bog transition. This facilitates the spatio-temporal reconstruction of mire development, which is based on 212 in situ tree stumps in the case study presented here. Six dendrochronologically dated site chronologies together cover 2345 years between 6703 and 3403 BC. The gaps in between are 6 to 550 years long. Additionally, a floating chronology of 309 years, containing 30 trees, was radiocarbon-dated to the beginning of the 7th millennium cal BC. Peat-stratigraphical survey was carried out additionally, and elevations a.s.l. were determined at several locations. Tree dying-off phases, which indicate water level rise at the site, mostly in context of the local fen-bog transition, are evident for ca. 6600-6450, ca. 6350-5750, ca. 5300-4900, ca. 4700-4550, ca. 3900-3850, ca. 3700-3600, ca. 3500-3450 and ca. 3400 BC. The spatial distribution of the dated in situ trees illustrates the phase-wise expansion of raised bog over fen peat at the site. The documented bog expansion pulses likely correspond to climatic wet sifts.

  4. Plant component features of forest-bog ecotones of eutrophic paludification in the south of boreal forest zone of West Siberia

    Science.gov (United States)

    Klimova, N. V.; Chernova, N. A.; Pologova, N. N.

    2018-03-01

    Paludified forests formed in transitional forest-bog zone aren’t studied enough, inspite of its high expected diversity and large areas in the south of boreal forest zone of West Siberia. In this article wet birch (Betula pubescens) forests of forest-bog ecotones of eutrophic paludification are investigated on Vasyugan plain with nutrient-rich calcareous clays as soil-forming rocks. Species diversity and ecocoenotic structure of these phytocoenoses are discussed. They correlated with wetness and nutrient-availability of habitats evaluated with indicator values of plants. The participation of hydrophylous species is increasing as wetness of habitats increasing in the forest-to-bog direction like in mesotrophic paludification series. However the number of species is higher in the phytocoenoses of eutrophic paludification. The share of species required to nutrient availability is also higher, both in number and in abundance. A lot of these species are usual for eutrophic boreal forested swamps with groundwater input and absent in forests of mesotrophic paludification. Accordingly the nutrient-availability of habitats is also higher. All these features we connect with birch to be a forest forming species instead of dark-coniferous and with the influence of nutrient-rich parent rocks, which is evident in forest-bog ecotones of Vasyugan plain gradually decreasing together with peat horizon thickening.

  5. Hvordan jøderne blev til jøder i Esters bog

    DEFF Research Database (Denmark)

    Holt, Else Kragelund

    2015-01-01

    persere, der ikke ”bliver jøder”. Denne kamp tolkes som udtryk dels for en fællesskabsskabende effervescens (Durkheim), der bedst forstås gennem Purimfestens karnevaleske karakter, dels for mimetisk rivalisering (Girard), personificeret gennem Haman og Mordokaj. Purim og Esters Bog står således i en...

  6. Medical Imaging of Mummies and Bog Bodies

    DEFF Research Database (Denmark)

    Lynnerup, Niels

    2010-01-01

    Mummies are human remains with preservation of non-bony tissue. Mummification by natural influences results in so-called natural mummies, while mummification induced by active (human) intervention results in so-called artificial mummies, although many cultures practiced burial rites which to some...... and bog bodies could be studied non-destructively. This article describes the history of mummy radiography and CT scanning, and some of the problems and opportunities involved in applying these techniques, derived for clinical use, on naturally and artificially preserved ancient human bodies. Unless...... severely degraded, bone is quite readily visualized, but accurate imaging of preserved soft tissues, and pathological lesions therein, may require considerable post-image capture processing of CT data....

  7. Multi-omics of permafrost, active layer and thermokarst bog soil microbiomes.

    Science.gov (United States)

    Hultman, Jenni; Waldrop, Mark P; Mackelprang, Rachel; David, Maude M; McFarland, Jack; Blazewicz, Steven J; Harden, Jennifer; Turetsky, Merritt R; McGuire, A David; Shah, Manesh B; VerBerkmoes, Nathan C; Lee, Lang Ho; Mavrommatis, Kostas; Jansson, Janet K

    2015-05-14

    Over 20% of Earth's terrestrial surface is underlain by permafrost with vast stores of carbon that, once thawed, may represent the largest future transfer of carbon from the biosphere to the atmosphere. This process is largely dependent on microbial responses, but we know little about microbial activity in intact, let alone in thawing, permafrost. Molecular approaches have recently revealed the identities and functional gene composition of microorganisms in some permafrost soils and a rapid shift in functional gene composition during short-term thaw experiments. However, the fate of permafrost carbon depends on climatic, hydrological and microbial responses to thaw at decadal scales. Here we use the combination of several molecular 'omics' approaches to determine the phylogenetic composition of the microbial communities, including several draft genomes of novel species, their functional potential and activity in soils representing different states of thaw: intact permafrost, seasonally thawed active layer and thermokarst bog. The multi-omics strategy reveals a good correlation of process rates to omics data for dominant processes, such as methanogenesis in the bog, as well as novel survival strategies for potentially active microbes in permafrost.

  8. Functioning of microbial complexes in aerated layers of a highmoor peat bog

    Science.gov (United States)

    Golovchenko, A. V.; Bogdanova, O. Yu.; Stepanov, A. L.; Polyanskaya, L. M.; Zvyagintsev, D. G.

    2010-09-01

    Monitoring was carried out using the luminescent-microscopic method of the abundance parameters of different groups of microorganisms in a monolith and in the mixed layers of a highmoor peat bog (oligotrophic residual-eutrophic peat soil) in a year-long model experiment. The increase of the aeration as a result of mixing of the layers enhanced the activity of the soil fungi. This was attested to by the following changes: the increase of the fungal mycelium length by 6 times and of the fungal biomass by 4 times and the double decrease of the fraction of spores in the fungal complex. The response of the fungal complex to mixing was different in the different layers of the peat bog. The maximal effect was observed in the T1 layer and the minimal one in the T2 layer. The emission of CO2 in the mixed samples was 1.5-2 times higher than that from the undisturbed peat samples. In contrast with the fungi, the bacteria and actinomycetes were not affected by the aeration of the highmoor layers.

  9. Low impact of dry conditions on the CO2 exchange of a Northern-Norwegian blanket bog

    International Nuclear Information System (INIS)

    Lund, Magnus; Parmentier, F J W; Bjerke, J W; Tømmervik, H; Drake, B G; Engelsen, O; Hansen, G H; Powell, T L; Silvennoinen, H; Weldon, S; Rasse, D P; Sottocornola, M

    2015-01-01

    Northern peatlands hold large amounts of organic carbon (C) in their soils and are as such important in a climate change context. Blanket bogs, i.e. nutrient-poor peatlands restricted to maritime climates, may be extra vulnerable to global warming since they require a positive water balance to sustain their moss dominated vegetation and C sink functioning. This study presents a 4.5 year record of land–atmosphere carbon dioxide (CO 2 ) exchange from the Andøya blanket bog in northern Norway. Compared with other peatlands, the Andøya peatland exhibited low flux rates, related to the low productivity of the dominating moss and lichen communities and the maritime settings that attenuated seasonal temperature variations. It was observed that under periods of high vapour pressure deficit, net ecosystem exchange was reduced, which was mainly caused by a decrease in gross primary production. However, no persistent effects of dry conditions on the CO 2 exchange dynamics were observed, indicating that under present conditions and within the range of observed meteorological conditions the Andøya blanket bog retained its C uptake function. Continued monitoring of these ecosystem types is essential in order to detect possible effects of a changing climate. (letter)

  10. Purple pitcher plant (Sarracenia rosea Dieback and partial community disassembly following experimental storm surge in a coastal pitcher plant bog.

    Directory of Open Access Journals (Sweden)

    Matthew J Abbott

    Full Text Available Sea-level rise and frequent intense hurricanes associated with climate change will result in recurrent flooding of inland systems such as Gulf Coastal pitcher plant bogs by storm surges. These surges can transport salt water and sediment to freshwater bogs, greatly affecting their biological integrity. Purple pitcher plants (Sarracenia rosea are Gulf Coast pitcher plant bog inhabitants that could be at a disadvantage under this scenario because their pitcher morphology may leave them prone to collection of saline water and sediment after a surge. We investigated the effects of storm surge water salinity and sediment type on S. rosea vitality, plant community structure, and bog soil-water conductivity. Plots (containing ≥1 ramet of S. rosea were experimentally flooded with fresh or saline water crossed with one of three sediment types (local, foreign, or no sediment. There were no treatment effects on soil-water conductivity; nevertheless, direct exposure to saline water resulted in significantly lower S. rosea cover until the following season when a prescribed fire and regional drought contributed to the decline of all the S. rosea to near zero percent cover. There were also significant differences in plant community structure between treatments over time, reflecting how numerous species increased in abundance and a few species decreased in abundance. However, in contrast to S. rosea, most of the other species in the community appeared resilient to the effects of storm surge. Thus, although the community may be somewhat affected by storm surge, those few species that are particularly sensitive to the storm surge disturbance will likely drop out of the community and be replaced by more resilient species. Depending on the longevity of these biological legacies, Gulf Coastal pitcher plant bogs may be incapable of fully recovering if they become exposed to storm surge more frequently due to climate change.

  11. Erik Rasmussen, Niels Bohr og Værdirelativismen - i anledning af Kasper Lippert-Rasmussens bog om Erik Rasmussen

    DEFF Research Database (Denmark)

    Ougaard, Morten

    2015-01-01

    En svaghed ved Kasper Lippert-Rasmussens i øvrigt udmærkede bog om Erik Rasmussen er, at den forbigår den sene Rasmussens bog om komplementaritet og statskundskab. Bogen var vigtig for Rasmussen, og den bør indgå i hans faglige eftermæle. Den rummer videnskabsteoretiske argumenter af stor relevans...... ikke mindst forholdet mellem normative og kognitive udsagn. Efter mødet med Niels Bohrs filosofi står Rasmussens værdirelativisme både skarpere og stærkere end før, og Kasper Lippert-Rasmussens karakteristik af denne position som et ubegrundet dogme i dansk politologi er ikke overbevisende....

  12. Habitat and species controls on Sphagnum production and decomposition in a mountain raised bog

    Czech Academy of Sciences Publication Activity Database

    Hájek, Tomáš

    2009-01-01

    Roč. 14, č. 6 (2009), s. 947-958 ISSN 1239-6095 R&D Projects: GA AV ČR KJB600050503 Institutional research plan: CEZ:AV0Z60050516 Keywords : bog * production * decomposition Subject RIV: EF - Botanics Impact factor: 1.467, year: 2009

  13. Annual greenhouse gas budget for a bog ecosystem undergoing restoration by rewetting

    Directory of Open Access Journals (Sweden)

    S.-C. Lee

    2017-06-01

    Full Text Available Many peatlands have been drained and harvested for peat mining, agriculture, and other purposes, which has turned them from carbon (C sinks into C emitters. Rewetting of disturbed peatlands facilitates their ecological recovery and may help them revert to carbon dioxide (CO2 sinks. However, rewetting may also cause substantial emissions of the more potent greenhouse gas (GHG methane (CH4. Our knowledge of the exchange of CO2 and CH4 following rewetting during restoration of disturbed peatlands is currently limited. This study quantifies annual fluxes of CO2 and CH4 in a disturbed and rewetted area located in the Burns Bog Ecological Conservancy Area in Delta, BC, Canada. Burns Bog is recognized as the largest raised bog ecosystem on North America's west coast. Burns Bog was substantially reduced in size and degraded by peat mining and agriculture. Since 2005, the bog has been declared a conservancy area, with restoration efforts focusing on rewetting disturbed ecosystems to recover Sphagnum and suppress fires. Using the eddy covariance (EC technique, we measured year-round (16 June 2015 to 15 June 2016 turbulent fluxes of CO2 and CH4 from a tower platform in an area rewetted for the last 8 years. The study area, dominated by sedges and Sphagnum, experienced a varying water table position that ranged between 7.7 (inundation and −26.5 cm from the surface during the study year. The annual CO2 budget of the rewetted area was −179 ± 26.2 g CO2–C m−2 yr−1 (CO2 sink and the annual CH4 budget was 17 ± 1.0 g CH4–C m−2 yr−1 (CH4 source. Gross ecosystem productivity (GEP exceeded ecosystem respiration (Re during summer months (June–August, causing a net CO2 uptake. In summer, high CH4 emissions (121 mg CH4–C m−2 day−1 were measured. In winter (December–February, while roughly equal magnitudes of GEP and Re made the study area CO2 neutral, very low CH4 emissions (9 mg CH4–C m−2

  14. Tracing decadal environmental change in ombrotrophic bogs using diatoms from herbarium collections and transfer functions.

    Science.gov (United States)

    Poulíčková, Aloisie; Hájková, Petra; Kintrová, Kateřina; Bat'ková, Romana; Czudková, Markéta; Hájek, Michal

    2013-08-01

    Central European mountain bogs, among the most valuable and threatened of habitats, were exposed to intensive human impact during the 20th century. We reconstructed the subrecent water chemistry and water-table depths using diatom based transfer functions calibrated from modern sampling. Herbarium Sphagnum specimens collected during the period 1918-1998 were used as a source of historic diatom samples. We classified samples into hummocks and hollows according to the identity of dominant Sphagnum species, to reduce bias caused by uneven sampling of particular microhabitats. Our results provide clear evidence for bog pollution by grazing during the period 1918-1947 and by undocumented aerial liming in the early 90-ies. We advocate use of herbarized epibryon as a source of information on subrecent conditions in recently polluted mires. Copyright © 2013 Elsevier Ltd. All rights reserved.

  15. Tracing decadal environmental change in ombrotrophic bogs using diatoms from herbarium collections and transfer functions

    Czech Academy of Sciences Publication Activity Database

    Poulíčková, A.; Hájková, Petra; Kintrová, K.; Baťková, R.; Czudková, M.; Hájek, Michal

    2013-01-01

    Roč. 179, August (2013), s. 201-209 ISSN 0269-7491 R&D Projects: GA ČR GA206/08/0389 Institutional support: RVO:67985939 Keywords : epibyon * diatoms * bogs Subject RIV: EF - Botanics Impact factor: 3.902, year: 2013

  16. Relative importance of local habitat complexity and regional factors for assemblages of oribatid mites (Acari: Oribatida) in Sphagnum peat bogs.

    Science.gov (United States)

    Minor, M A; Ermilov, S G; Philippov, D A; Prokin, A A

    2016-11-01

    We investigated communities of oribatid mites in five peat bogs in the north-west of the East European plain. We aimed to determine the extent to which geographic factors (latitude, separation distance), local environment (Sphagnum moss species, ground water level, biogeochemistry) and local habitat complexity (diversity of vascular plants and bryophytes in the surrounding plant community) influence diversity and community composition of Oribatida. There was a significant north-to-south increase in Oribatida abundance. In the variance partitioning, spatial factors explained 33.1 % of variability in abundance across samples; none of the environmental factors were significant. Across all bogs, Oribatida species richness and community composition were similar in Sphagnum rubellum and Sphagnum magellanicum, but significantly different and less diverse in Sphagnum cuspidatum. Sphagnum microhabitat explained 52.2 % of variability in Oribatida species richness, whereas spatial variables explained only 8.7 %. There was no distance decay in community similarity between bogs with increased geographical distance. The environmental variables explained 34.9 % of the variance in community structure, with vascular plants diversity, bryophytes diversity, and ground water level all contributing significantly; spatial variables explained 15.1 % of the total variance. Overall, only 50 % of the Oribatida community variance was explained by the spatial structure and environmental variables. We discuss relative importance of spatial and local environmental factors, and make general inferences about the formation of fauna in Sphagnum bogs.

  17. Unexpected differences in butterfly diversity between two peat bogs in the same area

    Directory of Open Access Journals (Sweden)

    Klimczuk Przemysław

    2017-09-01

    Full Text Available Peat bogs are listed among the most threatened habitats in central Europe, a situation that is reflected by, for example, the conservational status of stenotopic butterflies. Even so, this group remains relatively little studied and most of the available data are limited to qualitative records. The present study enabled us to gain insight into the butterfly fauna of the two largest peat bogs in the Knyszyn Forest (NE Poland, i.e. Bagno Moskal and the one in the Jesionowe Góry nature reserve. The sites, only ca 10 km apart, are characterized by similar vegetation (mainly the Ledo-Sphagnetum association. The study was carried out in 2013-2015 using the transect method, i.e. regular counts along fixed routes. A total of 37 species, including three tyrphobionts (Colias palaeno, Plebejus optilete and Boloria eunomia and two tyrphophiles (Callophrys rubi and Boloria euphrosyne, were recorded. The greatest and unexpected differences between the sites were related to the complete absence of P. optilete at Bagno Moskal, the significantly higher abundance of B. eunomia at Jesionowe Góry and the greater abundance of B. euphrosyne at Bagno Moskal. In addition, C. palaeno was observed sporadically and only at Bagno Moskal. There was some heterogeneity in the distribution and density of particular species, however. Ledum palustre was found to be the most important nectar plant, its flowers also being frequently visited by tyrphoneutrals. The present study shows that isolated island-like habitats (e.g. peat bogs may possess specific features and be subject to specific independent changes. The results provide a good basis for further research into the habitat preferences of tyrphophilous and tyrphobiontic butterflies, which is important in the context of their conservation.

  18. Experimental Nitrogen Deposition Alters Post-fire Carbon Balance Recovery in Alberta Bogs

    Science.gov (United States)

    Wieder, R. K.; Vile, M. A.; Scott, K. D.; Albright, C. M.; McMillen, K.

    2016-12-01

    Bogs and fens occupy about 30% of the landscape across northern Alberta, Canada and function regionally as a net sink for atmospheric CO2-C, the strength of which is strongly influenced by the frequency and extent of wildfires. Alberta peatlands have persisted at the low end of the global range of annual atmospheric nitrogen (N) deposition (exchange, we experimentally applied N (as NH4NO3 solutions) to replicated plots at levels equivalent to controls (C: no water additions), 0 (water only), 10, and 20 kg/ha/yr at five bog sites, aged at 2, 12, 32, 73, and 113 years since fire in 2013 (hummocks and hollows in 6 plots per N treatment per site). Understory net ecosystem exchange of CO2 (NEE) was measured repeatedly throughout the 2013-2016 growing seasons using the closed chamber approach. Averaged across all years, sites, plots, and hummocks versus hollows, N addition stimulated NEE rates (C and 0 treatments: 0.46 µmol m-2 s-1; 10 and 20 treatments: 1.16 µmol m-2 s-1) and to a much lesser extent understory dark respiration (ER) rates (C and 0 treatments: -3.26 µmol m-2 s-1; 10 and 20 treatments: -3.43 µmol m-2 s-1). On an annual basis, averaged across all years, sites, and plots, N addition also stimulated NEE for hummocks (C and 0 treatments: -1.0 mol C m-2 yr-1; 10 and 20 treatments: 15.7 mol C m-2 yr-1), but not hollows. Experimental N addition had minimal effects on annual ER. The nature of the N response, however, differed between sites and years. Further, experimental N addition had no effect on the net primary production of Sphagnum fuscum, the dominant peat-forming moss. Thus, the enhancement of the net CO2-C sink through N addition occurs through stimulation of short-statured vascular shrub growth and biomass, with implications for the structure and function of bog understories as they recover after fire under different N deposition regimes.

  19. Sorption of radioiodide in an acidic, nutrient-poor boreal bog: insights into the microbial impact

    International Nuclear Information System (INIS)

    Lusa, M.; Bomberg, M.; Aromaa, H.; Knuutinen, J.; Lehto, J.

    2015-01-01

    Batch sorption experiments were conducted to evaluate the sorption behaviour of iodide and the microbial impact on iodide sorption in the surface moss, subsurface peat, gyttja, and clay layers of a nutrient-poor boreal bog. The batch distribution coefficient (K d ) values of iodide decreased as a function of sampling depth. The highest K d values, 4800 L/Kg dry weight (DW) (geometric mean), were observed in the fresh surface moss and the lowest in the bottom clay (geometric mean 90 mL/g DW). In the surface moss, peat and gyttja layers, which have a high organic matter content (on average 97%), maximum sorption was observed at a pH between ∼4 and 5 and in the clay layer at pH 2. The K d values were significantly lower in sterilized samples, being 20-fold lower than the values found for the unsterilized samples. In addition, the recolonization of sterilized samples with a microbial population from the fresh samples restored the sorption capacity of surface moss, peat and gyttja samples, indicating that the decrease in the sorption was due to the destruction of microbes and supporting the hypothesis that microbes are necessary for the incorporation of iodide into the organic matter. Anoxic conditions reduced the sorption of iodide in fresh, untreated samples, similarly to the effect of sterilization, which supports the hypothesis that iodide is oxidized into I 2 /HIO before incorporation into the organic matter. Furthermore, the K d values positively correlated with peroxidase activity in surface moss, subsurface peat and gyttja layers at +20 °C, and with the bacterial cell counts obtained from plate count agar at +4 °C. Our results demonstrate the importance of viable microbes for the sorption of iodide in the bog environment, having a high organic matter content and a low pH. - Highlights: • Sorption of iodide is highest on the surface Sphagnum layer of the bog. • Sterilization of peat decreases the sorption of iodide. • Anoxic conditions decrease

  20. Seasonal variations in CO2 and CH4 fluxes of four different plant compositions of a Sphagnum-dominated Alpine peat bog

    Science.gov (United States)

    Drollinger, Simon; Maier, Andreas; Karer, Jasmin; Glatzel, Stephan

    2017-04-01

    Peatlands are the only type of ecosystems which have the ability to accumulate significant amounts of carbon (C) under undisturbed conditions. The amount of C sequestered in peatlands depends on the balance between gross primary production, ecosystem respiration and decomposition of plant material. Sphagnum-dominated bogs possess the greatest peat accumulation potential of all peatlands, thus in turn, feature highest C release potentials. Many studies report about the C balances of undisturbed northern peat bogs, however, little is known about the effects of peatland degradation on the C balance between different plant compositions within peat bog ecosystems. Particularly in the Alpine region, where temperature increase during the last century has been almost twice as high as the global mean. The investigated peat bog is located in the inner Alpine Enns valley in the Eastern Alps, Austria (N 47˚ 34.873' E 14˚ 20.810'). It is a pine peat bog covered by Sphagnum mosses and a present extent of about 62 ha. Due to increasing differences in surface height of the peatland compared to the surrounding areas and related lowered water retention capacity attributed to the subsidence of the adjacent intensively managed meadows on deeply drained peat soils, the function of the peatland as a carbon sink is strongly endangered. Hence, the current mean water table depth of the central peat bog area is about -12 cm. To reveal differences in peatland-atmosphere C exchanges within the peatland ecosystem, we investigated CO2 and CH4 fluxes of four different vegetation compositions (PM1-PM4) at the treeless central peat bog area. PM1 is dominated by the graminoids Rhynchospora alba and Eriophorum vaginatum. PM2 is inhabited by small individuals (< 35 cm) of the conifer Pinus mugo, whereas PM3 is dominated by the ericaceous plant Calluna vulgaris. PM4 again is populated by Pinus mugo, but higher growing (35 - 60 cm) and with corresponding higher amount of biomass. Fluxes were measured

  1. Distribution and speciation of mercury in the peat bog of Xiaoxing'an Mountain, northeastern China

    International Nuclear Information System (INIS)

    Liu Ruhai; Wang Qichao; Lu Xianguo; Fang Fengman; Wang Yan

    2003-01-01

    Peat bogs in northeastern China contain high levels of mercury from atmospheric deposition. - Most reports on mercury (Hg) in boreal ecosystems are from the Nordic countries and North America. Comparatively little information is available on Hg in wetlands in China. We present here a study on Hg in the Tangwang River forested catchment of the Xiaoxing'an Mountain in the northeast of China. The average total Hg (THg) in peat profile ranged from 65.8 to 186.6 ng g -1 dry wt with the highest at the depth of 5-10 cm. THg in the peat surface was higher than the background in Heilongjiang province, the Florida Everglades, and Birkeness in Sweden. MethylHg (MeHg) concentration ranged from 0.16 to 1.86 ng g -1 dry wt, with the highest amount at 10-15 cm depth. MeHg content was 0.2-1.2% of THg. THg and MeHg all decreased with the depth. THg in upland layer of soil (0-20 cm) was comparable to the peat surface, but in deeper layers THg concentration in peat was much higher than that in the forested mineral soil. THg in the peat bog increased, but MeHg decreased after it was drained. THg content in plant was different; THg contents in moss (119 ng g -1 dry wt, n=12) were much higher than in the herbage, the arbor, and the shrubs. The peat bog has mainly been contaminated by Hg deposition from the atmosphere

  2. Potassium limits potential growth of bog vegetation under elevated atmospheric CO2 and N deposition

    NARCIS (Netherlands)

    Hoosbeek, M.R.; Breemen, van N.; Vasander, H.; Buttlers, A.; Berendse, F.

    2002-01-01

    The free air carbon dioxide enrichment (FACE) and N deposition experiments on four ombrotrophic bogs in Finland, Sweden, the Netherlands and Switzerland, revealed that after three years of treatment: (1) elevated atmospheric CO2 concentration had no significant effect on the biomass growth of

  3. Increased aeolian activity during humidity shifts as recorded in a raised bog in south-west Sweden during the past 1700 years

    Directory of Open Access Journals (Sweden)

    R. de Jong

    2007-07-01

    Full Text Available Analyses of testate amoebae and aeolian sediment influx (ASI were used to reconstruct effective humidity changes and aeolian activity in the coastal zone of south-west Sweden. Cores were taken from an ombrotrophic peat sequence from the Undarsmosse bog. Since both types of analysis were carried out on the same core, a direct comparison between humidity fluctuations in the bog and aeolian activity was possible, potentially providing detailed information on atmospheric circulation changes in this region. Relatively wet bog surface conditions occurred from around 1500 to 1230 and 770 to 380 cal. yrs BP, whereas dry conditions dominated from ca. 1630 to 1530, 1160 to 830 and 300 to 50 cal. yrs BP. The transitions between these phases occurred within 60–100 years and are characterised by a major change in the testate amoebae assemblages. A watertable reconstruction was used to study the hydrological changes at the bog surface in more detail. ASI peak events were reconstructed around 1450, 1150, 850 and after 370 cal. yrs BP. Most interestingly, these aeolian activity peaks started during the recorded hydrological transitions, regardless of the direction of these shifts. Our results therefore suggest that humidity shifts in this region were associated with temporary intensifications of atmospheric circulation during the past 1700 years. Several ASI peaks apparently coincide with reduced solar activity, possibly suggesting a solar related cause for some of the observed events.

  4. Bottlenecks in bog pine multiplication by somatic embryogenesis and their visualization with the environmental scanning electron microscope.

    Science.gov (United States)

    Vlašínová, Helena; Neděla, Vilem; Đorđević, Biljana; Havel, Ladislav

    2017-07-01

    Somatic embryogenesis (SE) is an important biotechnological technique used for the propagation of many pine species in vitro. However, in bog pine, one of the most endangered tree species in the Czech Republic, limitations were observed, which negatively influenced the development and further germination of somatic embryos. Although initiation frequency was very low-0.95 %, all obtained cell lines were subjected to maturation. The best responding cell line (BC1) was used and subjected to six different variants of the maturation media. The media on which the highest number of early-precotyledonary/cotyledonary somatic embryos was formed was supplemented with 121 μM abscisic acid (ABA) and with 6 % maltose. In the end of maturation experiments, different abnormalities in formation of somatic embryos were observed. For visualization and identification of abnormalities in meristem development during proliferation and maturation processes, the environmental scanning electron microscope was used. In comparison to the classical light microscope, the non-commercial environmental scanning electron microscope AQUASEM II has been found as a very useful tool for the quick recognition of apical meristem disruption and abnormal development. To our knowledge, this is the first report discussing somatic embryogenesis in bog pine. Based on this observation, the cultivation procedure could be enhanced and the method for SE of bog pine optimized.

  5. Response of a Sphagnum bog plant community to elevated CO2 and N supply

    NARCIS (Netherlands)

    Heijmans, M.M.P.D.; Klees, H.; Visser, de W.; Berendse, F.

    2002-01-01

    The response of plant growth to rising CO2 levels appears to depend on nutrient availability, but it is not known whether the growth of bog plants reacts similarly. We therefore studied the effects of elevated CO2 in combination with N supply on the growth of Sphagnum mosses and vascular plants in

  6. Holocene palaeohydrological history of the Tǎul Muced peat bog (Northern Carpathians, Romania) based on testate amoebae (Protozoa) and plant macrofossils

    Science.gov (United States)

    Cosmin Diaconu, Andrei; Feurdean, Angelica; Lamentowicz, Mariusz; Gałka, Mariusz; Tanţǎu, Ioan

    2016-04-01

    Knowledge of past local vs. regional hydro-climate variability is a priority in climate research. This is because ecosystems and human depend on local climatic conditions and the magnitude of these climate changes is more variable at local and regional rather than at global scales. Ombrotrophic bogs are highly suitable for hydro-climate reconstructions as they are entirely dependent on the water from precipitation. We used stratigraphy, radiocarbon dating, testate amoebae (TA) and plant macrofossils on a peat profile from an ombrotrophic bog (Tǎul Muced) located in the Biosphere Reserve of the Rodna National Park Romania. We performed quantitative reconstruction of the depth to water table (DWT) and pH over the last 8000 years in a continental area of CE Europe. We identified six main stages in the development of the bog based on changes in TA assemblages in time. Wet conditions and pH between 2 and 4.5 were recorded between 4600-2750 and 1300-400 cal. yr BP, by the occurrence of Archerella flavum, Amphitrema wrightianum and Hyalosphenia papilio. This was associated to a local vegetation primarily composed of Sphagnum magellanicum and S. angustifolium. Dry stages and pH of 2.5 to 5 were inferred between 7550-4600, 2750-1300 and -50 cal. yr BP, by the dominance of Nebela militaris, Difflugia pulex and Phryganella acropodia. These overall dry conditions were also connected with increased abundance of Eriophorum vaginatum. The period between 400 and -50 cal. yr BP was characterized by a rapid shift from dry to wet conditions on the surface of the bog. Vegetation shifted from Sphagnum magellanicum to Sphagnum russowii dominated community. Our reconstruction remains in relatively good agreement with other palaeohydrological records from Central Eastern Europe. However, it shows contrasting conditions to others particularly with records from NW Europe. The valuable information regarding bog hydrology offered by our record puts an accent on the need of more regional TA

  7. Diet of Tollund Man. Stable isotope analyses of an Iron Age bog body from Denmark

    DEFF Research Database (Denmark)

    Helt Nielsen, Nina; Philippsen, Bente; Jensen, L. V.

    Tollund Man is one of the world’s most famous bog bodies due to his exceptionally well-preserved head. He was found in 1950 by peat cutters in a bog near Bjældskovdal, c. 10 km west of Silkeborg. During the years, several analyses have been performed on the body to shed light on the life and deat...... to dry out, and the bone sample could therefore be analysed without special pretreatment. The hair, on the other hand, had been treated with wax, which needed to be removed prior to analysis. The successful method of pre-treatment will be presented....... and hair of Tollund Man. The analysis of the isotopes of C, N and S reveals the diet on long and short time scales: The isotope signature in the bone sample reflects the average diet in the years prior to death; the isotope signature in the hair reflects the diet in the last months of his life. Any...

  8. Mid- and late Holocene human impact recorded by the Coltrondo peat bog (NE Italian Alps)

    Science.gov (United States)

    Segnana, Michela; Poto, Luisa; Gabrieli, Jacopo; Martino, Matteo; Oeggl, Klaus; Barbante, Carlo

    2016-04-01

    Peat bogs are ideal archives for the study of environmental changes, whether these are natural or human induced. Indeed, receiving water and nutrients exclusively from dry and wet atmospheric depositions, they are among the most suitable matrices for palaeoenvironmental reconstruction. The present study is focused on the Eastern sector of the Italian Alps, where we sampled the Coltrondo peat bog, in the Comelico area (ca. 1800 m a.s.l.) The knowledge of the human history in this area is rather scarce: the only pieces of archaeological evidence found in this area dates back to the Mesolithic and the absence of later archaeological finds makes it difficult to reconstruct the human settlement in the valley. With the main aim to obtain information about the human settlement in that area we selected a multi-proxy approach, combining the study of biotic and abiotic sedimentary components archived in the 7900 years-peat bog record. Pollen analysis is performed along the core registering human impacts on the area from ca. 2500 cal BP, when land-use changes are well evidenced by the presence of human-related pollen and non-pollen palynomorphs (NPPs), as well as by the increase in micro-charcoal particles. Periods of increased human impact are recorded at the end of the Middle Ages and later, at the end of the 19th century. The analysis of trace elements, such as lead, is performed by means of ICP-MS technique and its enrichment factor (EF) is calculated. A first slight increase of Pb EF during Roman Times is possibly related to mining activities carried out by the Romans. Mining activities carried out in the area are registered during the Middle Ages, while the advent of the industrialization in the 20th century is marked by the highest EF values registered on the top of the core. To help and support the interpretation of geochemical data, lead isotopes ratios are also measured using ICP-MS to discriminate between natural and anthropogenic sources of lead. The 206Pb/207Pb

  9. Isolated peat bog habitats and their food connections: parasitoids (Hymenoptera: Ichneumonoidea) and their lepidopteran hosts

    Czech Academy of Sciences Publication Activity Database

    Lozan, Aurel; Spitzer, Karel; Jaroš, Josef

    2012-01-01

    Roč. 16, č. 3 (2012), s. 391-397 ISSN 1366-638X Institutional research plan: CEZ:AV0Z50070508 Keywords : Paleorefugia * relict peat bogs * specific Lepidoptera Subject RIV: EH - Ecology, Behaviour Impact factor: 1.801, year: 2012 http://www.springerlink.com/content/78u173hn60701033/

  10. Effects of elevated CO2 and increased N deposition on bog vegetation in the Netherlands = [Gevolgen van een verhoogde atmosferische CO2-concentratie en N-depositie voor hoogveenvegetatie in Nederland

    NARCIS (Netherlands)

    Heijmans, M.M.P.D.

    2000-01-01

    Ombrotrophic bogs are important long-term sinks for atmospheric carbon. Changes in species composition of the bog plant community may have important effects on carbon sequestration, because peat mosses ( Sphagnum ) contribute more to peat accumulation than vascular

  11. High-resolution stratigraphy of the northernmost concentric raised bog in Europe : Sellevollmyra, Andoya, northern Norway

    NARCIS (Netherlands)

    Vorren, Karl-Dag; Wastegard, Stefan; Van Der Plicht, Johannes; Jensen, Christin; Wastegård, Stefan; Blaauw, Maarten

    2007-01-01

    From the Sellevollmyra bog at Andoya, northern Norway, a 440-cm long peat core covering the last c. 7000 calendar years was examined for humification, loss-on-ignition, microfossils, macrofossils and tephra. The age model was based on a Bayesian wiggle-match of 35 C-14 dates and two historically

  12. Role and Responsibility of Board of Governors [BOG] in Ensuring Educational Quality in Colleges & Universities

    Science.gov (United States)

    Naik, B. M.

    2012-01-01

    The paper presents in brief the need and importance of effective, imaginative and responsible governing boards in colleges and universities, so as to ensure educational quality. BOG should engage fruitfully with the principal and activities in college/ university. UGC, AICTE have now prescribed creation of effective boards for both government and…

  13. Variations in the D/H and 18O/16O ratios in cellulose extracted from a peat bog core

    International Nuclear Information System (INIS)

    Brenninkmeijer, C.A.M.; Mook, W.G.; Geel, B. van

    1982-01-01

    A peat core from a raised bog covering the period 3100 to 2400 14 C years B.P. has been analysed for D/H and 18 O/ 16 O ratios. These analyses were applied to cellulose, extracted from 56 successive layers of 1 cm thickness. D/H ratios were determined for the carbon bonded hydrogen; 18 O/ 16 O analyses were performed by applying a new method. For the interpretation of the results obtained on peat, the isotopic ratios of 11 living bog plant species were measured, showing a relatively large scatter. Most pronounced is a depletion in D of about 25per mille and in 18 O of about 5per mille of the Sphagnum mosses relative to the vascular bog plants. This different isotopic composition is reflected by the deltaD and delta 18 O records of the peat core, because the abundance of the remains of non-vascular plants is variable. If this effect is taken account of, the remaining deltaD variations appear to be too large to be attributed to variations in the isotopic compositions of precipitation. As palaeoclimatic indicators the D/H and 18 O/ 16 O ratio qualitatively agree with the pollen analytical evidence for the climatic deterioration of the Subboreal-Subatlantic transition. (orig.)

  14. Eddy covariance measurements of greenhouse gases from a restored and rewetted raised bog ecosystem.

    Science.gov (United States)

    Lee, S. C.; Christen, A.; Black, T. A.; Johnson, M. S.; Ketler, R.; Nesic, Z.; Merkens, M.

    2015-12-01

    Wetland ecosystems play a significant role in the global carbon (C) cycle. Wetlands act as a major long-term storage of carbon by sequestrating carbon-dioxide (CO2) from the atmosphere. Meanwhile, they can emit significant amounts of methane (CH4) due to anaerobic microbial decomposition. The Burns Bog Ecological Conservancy Area (BBECA) is recognized as one of Canada's largest undeveloped natural areas retained within an urban area. Historically, it has been substantially reduced in size and degraded by peat mining and agriculture. Since 2005, the bog has been declared a conservancy area, and the restoration efforts in BBECA focus on rewetting the disturbed ecosystems to promote a transition back to a raised bog. A pilot study measured CH4, CO2 and N2O exchanges in 2014 and concluded to monitor CO2, CH4 fluxes continuously. From the perspective of greenhouse gas (GHG) emissions, CO2 sequestered in bog needs to be protected and additional CO2 and CH4 emissions due to land-cover change need to be reduced by wise management. In this study, we measured the growing-season (June-September) fluxes of CO2 and CH4 exchange using eddy covariance (EC). A floating platform with an EC system for both CO2 (closed-path) and CH4 (open-path) began operation in June 2015. During the growing-season, gross ecosystem photosynthesis (GEP) and ecosystem respiration (Re) averaged 5.87 g C m-2 day-1 and 2.02 g C m-2 day-1, respectively. The magnitude of GEP and Re were lower than in previous studies of pristine northern peatlands. The daily average CH4 emission was 0.99 (±1.14) g C m-2 day-1 and it was higher than in most previous studies. We also characterized how environmental factors affected the seasonal dynamics of these exchanges in this disturbed peatland. Our measurements showed that soil temperature and soil water content were major drivers of seasonal changes of GHG fluxes. The daily average GHG warming potential (GWP) of the emissions in the growing seasons (from CO2 and CH4

  15. The occurence of rare and protected plant species on the peat bog near Lake Bikcze (Łęczyńsko-Włodawskie Lakeland

    Directory of Open Access Journals (Sweden)

    Magdalena Pogorzelec

    2012-12-01

    Full Text Available This paper presents the results of a pilot field study, conducted in July 2007, designed to make floristic evaluation of the peat bog area adjacent to the western shore of Lake Bikcze (Łęczyńsko-Włodawskie Lakeland. The main aim of the study was to confirm the occurrence of populations of rare and legally protected plant species in this area and to identify, on a preliminary basis, habitat conditions in their stands. The occurrence of populations of the following strictly protected plant species: Betula humilis, Salix lapponum, Salix myrtilloides, Carex limosa, Drosera intermedia, Drosera rotundifolia, Dactylorhiza incarnata; and partially protected species: Menyanthes trifoliata, has been confirmed in the studied peat bog. Both an investigation of abiotic factors, conducted in situ, and an analysis of the species composition of the flora in terms of habitat preferences of particular groups of taxa have shown that the described rare plant species find suitable conditions for their growth and development in the studied peat bog.

  16. Radiocarbon dating of Sphagnum cellulose from Mohos peat bog, East Carpathians

    Science.gov (United States)

    Hubay, Katalin; Braun, Mihály; Harangi, Sándor; Palcsu, László; Túri, Marianna; Rinyu, László; Molnár, Mihály

    2015-04-01

    This work focuses on building a high-resolution age-depth model for quantitative paleoclimate study from the Mohos peat bog, East Carpathians. Peats are important archives for Quaternary science, because they preserve environmental changes. To study the chronology of peat profiles the key is in the precise coring and reliable dating. However, many studies dealing with coring and radiocarbon dating of peat deposits they often shown problems with the proper methods and material. With our novel coring technique we reached undisturbed and uncompressed peat cores from the Mohos bog. A 10 meter deep peat profile was drilled in 2012 using a modified technique of a piston corer. The core presents a continuous peat profile from the last 11.500 cal. yr BP. The chronology was based on AMS radiocarbon analyses of the separated Sphagnum samples from different depths of the profile. The peat samples were wet sieved (40-280 μm) to avoid contamination by rootlets. Dry Sphagnum samples for AMS dating were prepared using the classical acid-base-acid (ABA) method completed with an oxidative bleaching step to get clean cellulose. Sphagnum cellulose samples were converted to CO2 and later graphite and measured by EnvironMICADAS accelerator mass spectrometry (AMS) in Hertelendi Laboratory (Debrecen, Hungary). Fine peat accumulation rate changes (sections with lowest accumulation values) were observed along the profile. Based on the chronology in further studies we want to focus special intervals to investigate environmental changes in the Holocene. Key words: peat, radiocarbon, cellulose

  17. Late Holocene palaeohydrological changes in a Sphagnum peat bog from NW Romania based on testate amoebae

    Directory of Open Access Journals (Sweden)

    Andrei-Cosmin Diaconu

    2016-04-01

    Full Text Available This paper investigates the possibility of reconstructing the palaeohydrological changes in an active Sphagnum peat bog from north-western Romania using testate amoebae fauna and organic matter content determined by loss on ignition (LOI. In total 28 taxa of testate amoebae were identified of which 11 were frequent enough to present a remarkable ecological significance. Based on the relative abundance of these taxa nine zones were identified, crossing from very wet to dry climate conditions. The wet periods identified are characterized by taxa like Centropyxis cassis, Amphitrema flavum and Hyalosphenia papilio, while in the dry periods Difflugia pulex and Nebela militaris thrive. We showed that combining qualitative information regarding hydrological preferences with the quantitative percentage data from the fossil record it is possible to obtain information regarding major surface moisture changes from the peat bog surface. Furthermore we identified a link between distribution of testate amoebae assemblages, organic matter variation and minerogenic material.

  18. Long-term recovery of peat bogs oiled by pipeline spills in northern Alberta

    International Nuclear Information System (INIS)

    Blenkinsopp, S.; Sergy, G.

    1996-01-01

    Sites in northern Alberta, in which oil spills occurred more than 23 years ago, were revisited. The Nipisi spill occurred when a rupture in the underground oil pipeline leaked 60,000 barrels of crude into a 25 acre bog, with very little drainage. It was one of the largest spills in Canadian history. The Rainbow spill was into a fen that was draining by subsurface seepage. Treatments at the time included burning, tilling, and fertilizer addition. The sites were revisited in order to take samples and to evaluate both the natural and enhanced recovery and the effectiveness of the cleanup techniques. The long-term persistence of oil residues and changes in oil character resulting from weathering and biodegradation over time, were studied. Results showed that samples of oil residue and vegetation were still highly contaminated with oil which was heavily degraded. Subsurface samples were contaminated but the oil was only slightly degraded. The Nipisi site still had large areas devoid of vegetation. The unique drainage of peat bogs and the influence it has on rehabilitation was described. It was concluded that although the sites are recovering, they are doing so at a very slow pace and will require some more time to be complete. 12 refs., 4 tabs., 9 figs

  19. A single well pumping and recovery test to measure in situ acrotelm transmissivity in raised bogs

    NARCIS (Netherlands)

    Schaaf, van der S.

    2004-01-01

    A quasi-steady-state single pit pumping and recovery test to measure in situ the transmissivity of the highly permeable upper layer of raised bogs, the acrotelm, is described and discussed. The basic concept is the expanding depression cone during both pumping and recovery. It is shown that applying

  20. Dating raised bogs : New aspects of AMS C-14 wiggle matching, a reservoir effect and climatic change

    NARCIS (Netherlands)

    Kilian, MR; VanDerPlicht, J; VanGeel, B; Geel, B. van

    1995-01-01

    High resolution AMS dating of Holocene raised bog deposits (Engbertsdijksvenen, The Netherlands) shows natural C-14 variations (wiggles) which can be matched with the dendrochronological calibration curve. Comparison of our results with other, conventionally dated peat cores and the Delta(14)C

  1. GPR attenuation analyses using spectral ratios of primary and multiple arrivals: examples from Welsh peat bogs

    Science.gov (United States)

    Booth, A.; Carless, D.; Kulessa, B.

    2014-12-01

    Ground penetrating radar (GPR) is widely applied to qualitative and quantitative interpretation of near-surface targets. Surface deployments of GPR most widely characterise physical properties in terms of some measure of GPR wavelet velocity. Wavelet amplitude is less-often considered, potentially due to difficulties in measuring this quantity: amplitudes are distorted by the anisotropic radiation pattern of antennas, and the ringy GPR wavelet can make successive events difficult to isolate. However, amplitude loss attributes could provide a useful means of estimating the physical properties of a target. GPR energy loss is described by the bandwidth-limited quality factor Q* which, for low-loss media, is proportional to the ratio of dielectric permittivity, ɛ, and electrical conductivity, σ. Comparing the frequency content of two arrivals yields an estimate of interval Q*, but only if they are sufficiently distinct. There may be sufficient separation between a primary reflection and its long-path multiple (i.e. a 'repeat path' of the primary reflection) therefore a dataset that is rich in multiples may be suitable for robust Q* analysis. The Q* between a primary and multiple arrival describes all frequency-dependent loss mechanisms in the interval between the free-surface and the multiple-generating horizon: assuming that all reflectivity is frequency-independent, Q* can be used to estimate ɛ and/or σ. We measure Q* according to the spectral ratio method, for synthetic and real GPR datasets. Our simulations are performed using the finite-difference algorithm GprMax, and represent our example data of GPR acquisitions over peat bogs. These data are a series of 100 MHz GPR acquisitions over sites in the Brecon Beacons National Park of South Wales. The base of the bogs (the basal peat/mineral soil contact) is often a strong multiple-generating horizon. As an example, data from Waun Ddu bog show these events lagging by ~75 ns: GPR velocity is measured here at 0

  2. Nutrient additions in pristine Patagonian Sphagnum bog vegetation: can phosphorus addition alleviate (the effects of) increased nitrogen loads.

    Science.gov (United States)

    Fritz, C; van Dijk, G; Smolders, A J P; Pancotto, V A; Elzenga, T J T M; Roelofs, J G M; Grootjans, A P

    2012-05-01

    Sphagnum-bog ecosystems have a limited capability to retain carbon and nutrients when subjected to increased nitrogen (N) deposition. Although it has been proposed that phosphorus (P) can dilute negative effects of nitrogen by increasing biomass production of Sphagnum mosses, it is still unclear whether P-addition can alleviate physiological N-stress in Sphagnum plants. A 3-year fertilisation experiment was conducted in lawns of a pristine Sphagnum magellanicum bog in Patagonia, where competing vascular plants were practically absent. Background wet deposition of nitrogen was low (≈ 0.1-0.2 g · N · m(-2) · year(-1)). Nitrogen (4 g · N · m(-2) · year(-1)) and phosphorus (1 g · P · m(-2) · year(-1)) were applied, separately and in combination, six times during the growing season. P-addition substantially increased biomass production of Sphagnum. Nitrogen and phosphorus changed the morphology of Sphagnum mosses by enhancing height increment, but lowering moss stem density. In contrast to expectations, phosphorus failed to alleviate physiological stress imposed by excess nitrogen (e.g. amino acid accumulation, N-saturation and decline in photosynthetic rates). We conclude that despite improving growth conditions by P-addition, Sphagnum-bog ecosystems remain highly susceptible to nitrogen additions. Increased susceptibility to desiccation by nutrients may even worsen the negative effects of excess nitrogen especially in windy climates like in Patagonia. © 2011 German Botanical Society and The Royal Botanical Society of the Netherlands.

  3. How Phosphorus Availability Affects the Impact of Nitrogen Deposition on Sphagnum and Vascular Plants in Bogs

    NARCIS (Netherlands)

    Limpens, J.; Berendse, F.; Klees, H.

    2004-01-01

    To elucidate the impact of high nitrogen (N) deposition on intact bog vegetation, as affected by phosphorus (P) availability, we conducted a 4-year fertilization experiment with N and P at six sites, one with moderate N deposition and five with high N deposition. During the growing season, N (40 kg

  4. Rates and Controls of N2 Fixation in Sphagnum spp. along the Hydrological Gradient - Beaver Pond to Bog Transition at Mer Bleue, Ontario, Canada

    Science.gov (United States)

    Zivkovic, T.; Moore, T. R.

    2014-12-01

    Many northern bogs with low atmospheric N inputs acquire N only via N2-fixation. Little is known about rates and controls on N2-fixation in bogs. The aim of this study was to: 1) test the important ecological drivers for N2-fixation, 2) investigate seasonal and temporal patterns of N2 fixation, and 3) to estimate current N2-fixation rates at Mer Bleue bog. We used acetylene reduction assay (ARA) to measure N2-fixation from June-October 2013 and 2014 (currently ongoing field season) along a hydrological gradient (beaver pond, hollows and hummocks). The highest ARA rates in 2013 growing season occurred in the pond in floating Sphagnum cuspidatum mats (50.3 ± 12.9 μmol m-2 d-1 Mean ± Std Err) which were up to 2.5 times latger than the rates found in the hummock with the lowest water table depth throughout the season. Two rain events during the summer 2013 increased ARA rates in all plots by 1 to 4 times, suggesting that moisture availability may play a crucial role on N2 fixation potential in the field. We are currently investigating the role of moisture, temperature, PAR and nutrient content (N, phosphorous and metals) on ARA along the gradient. In addition, we are using 15N2 enrichment method to estimate N2 fixation rates and compare them to ARA method at Mer Bleue bog.

  5. A preliminary population study of alcove bog orchid (Platanthera zothecina) at Navajo National Monument, Arizona

    Science.gov (United States)

    Laura E. Hudson

    2001-01-01

    This study on Platanthera zothecina (alcove bog orchid) was initiated by the National Park Service after a recent threatened and endangered species survey at Navajo National Monument. It is listed as Category 2 (species of special concern) by the U.S. Fish and Wildlife Service, and Category 3 (likely to become endangered) by the Navajo Nation. Because P. zothecina is a...

  6. Pedochronology and development of peat bog in the environmental protection area pau-de-fruta - Diamantina, Brazil

    Directory of Open Access Journals (Sweden)

    José Ricardo da Rocha Campos

    2010-12-01

    Full Text Available In the region of the Serra do Espinhaço Meridional, peat bog is formed in hydromorphic environments developed in sunken areas on the plain surfaces with vegetation adapted to hydromorphic conditions, favoring the accumulation and preservation of organic matter. This pedoenvironment is developed on the regionally predominant quartzite rocks. Peat bog in the Environmental Protection Area - APA Pau-de-Fruta, located in the watershed of Córrego das Pedras, Diamantina,Brazil, was mapped and three representative profiles were morphologically characterized and sampled for physical, chemical and microbiological analyses. The organic matter was fractionated into fulvic acid (FA, humic acids (HA and humin (H. Two profiles were sampled to determine the radiocarbon age and δ13C. The structural organization of the three profiles is homogeneous. The first two layers consist of fibric, the two subsequent of hemic and the four deepest of sapric peat, showing that organic matter decomposition advances with depth and that the influence of mineral materials in deeper layers is greater. Physical properties were homogeneous in the profiles, but varied in the sampled layers. Chemical properties were similar in the layers, but the Ca content, sum of bases and base saturation differed between profiles. Contents of H predominated in the more soluble organic matter fractions and were accumulated at a higher rate in the surface and deeper layers, while HA levels were higher in the intermediate and FA in the deeper layers. Microbial activity did not vary among profiles and was highest in the surface layers, decreasing with depth. From the results of radiocarbon dating and isotope analysis, it was inferred that bog formation began about 20 thousand years ago and that the vegetation of the area had not changed significantly since then.

  7. Anomalous concentrations of zinc and copper in highmoor peat bog, southeast coast of Lake Baikal

    Science.gov (United States)

    Bobrov, V. A.; Bogush, A. A.; Leonova, G. A.; Krasnobaev, V. A.; Anoshin, G. N.

    2011-08-01

    When examining the peat deposit discovered in Vydrinaya bog, South Baikal region, the authors encountered anomalous Zn and Cu concentrations for highmoors being up to 600-500 ppm on a dry matter basis in the Early Holocene beds (360-440 cm) formed 11 000-8500 years ago. It has been demonstrated that Zn and Cu are present inside the plant cells of peat moss in the form of authigenic sulfide minerals of micron size. Apart from Zn and Cu, native Ag particles (5-7 um) have been encountered in the peat of the Vydrinaya bog at a depth of 390-410 cm; these particles formed inside the organic matter of the plasma membrane of peat moss containing Ca, Al, S, and Cu. This study suggests probable patterns of the formation of zinc sulfides, copper sulfides, and native silver in peat moss. The results obtained indicate that biogenic mineral formation plays a significant role in this system, which is a very important argument in the discussion on the ore genesis, in which physicochemical processes are normally favored, while the role of living matter is quite frequently disregarded.

  8. Nutrient additions in pristine Patagonian Sphagnum bog vegetation : can phosphorus addition alleviate (the effects of) increased nitrogen loads

    NARCIS (Netherlands)

    Fritz, C.; Dijk, G. van; Smolders, A.J.P.; Pancotto, V.A.; Elzenga, J.T.M.; Roelofs, J.G.M.; Grootjans, A.P.

    Sphagnum-bog ecosystems have a limited capability to retain carbon and nutrients when subjected to increased nitrogen (N) deposition. Although it has been proposed that phosphorus (P) can dilute negative effects of nitrogen by increasing biomass production of Sphagnum mosses, it is still unclear

  9. Fine-root growth in a forested bog is seasonally dynamic, but shallowly distributed in nutrient-poor peat

    Science.gov (United States)

    Colleen M. Iversen; Joanne Childs; Richard J. Norby; Todd A. Ontl; Randall K. Kolka; Deanne J. Brice; Karis J. McFarlane; Paul J. Hanson

    2017-01-01

    Background and aims. Fine roots contribute to ecosystem carbon, water, and nutrient fluxes through resource acquisition, respiration, exudation, and turnover, but are understudied in peatlands. We aimed to determine how the amount and timing of fine-root growth in a forested, ombrotrophic bog varied across gradients of vegetation density, peat...

  10. Microclimate of a peat bog and of the forest in different states of damage in the Šumava National Park

    Czech Academy of Sciences Publication Activity Database

    Hojdová, M.; Hais, M.; Pokorný, Jan

    2005-01-01

    Roč. 11, č. 1 (2005), s. 13-24 ISSN 1211-7420 Institutional research plan: CEZ:AV0Z60870520 Keywords : dying forest * microclimate * peat bog * remote sensing * temperature amplitude Subject RIV: EH - Ecology, Behaviour

  11. Effects of bryophytes on succession from alkaline marsh to Sphagnum bog

    Energy Technology Data Exchange (ETDEWEB)

    Glime, J.M.; Wetzel, R.G.; Kennedy, B.J.

    1982-10-01

    The alkaline eastern marsh of Lawrence Lake, a marl lake in southwestern Michigan, was sampled by randomly placed line transects to determine the bryophyte cover and corresponding vascular plant zones. Cluster analysis indicated three distinct bryophyte zones which correspond with the recognized vascular plant zones. Mosses occupied over 50% of the surface in some areas. Invasion of Sphagnum, vertical zonation of the mosses on hummocks, zonation with distance from the lake, the abundance of non-Sphagnum moss hummocks, and the ability of the non-Sphagnum species to lower the pH of marsh water during laboratory incubations are evidence that non-Sphagnum mosses facilitate succession from alkaline marsh to Sphagnum bog.

  12. Comparisons of soil nitrogen mass balances for an ombrotrophic bog and a minerotrophic fen in northern Minnesota

    Science.gov (United States)

    Brian H. Hill; Terri M. Jicha; LaRae L.P. Lehto; Colleen M. Elonen; Stephen D. Sebestyen; Randy Kolka

    2016-01-01

    Wecompared nitrogen (N) storage and flux in soils froman ombrotrophic bogwith that of a minerotrophic fen to quantify the differences in N cycling between these two peatlands types in northernMinnesota (USA). Precipitation, atmospheric deposition, and bog and fen outflowswere analyzed for nitrogen species. Upland and peatland soil sampleswere analyzed for N content,...

  13. Zavarzinella formosa gen. nov., sp. nov., a novel stalked, Gemmata-like planctomycete from a Siberian peat bog

    NARCIS (Netherlands)

    Kulichevskaya, I.S.; Baulina, O.I.; Bodelier, P.L.E.; Rijpstra, W.I.C.; Sinninghe Damsté, J.S.; Dedysh, S.N.

    2009-01-01

    An aerobic, pink-pigmented, budding and rosette-forming bacterium was isolated from an acidic Sphagnum peat bog and designated strain A10T. The 16S rRNA gene sequence analysis showed that strain A10T was a member of the order Planctomycetales and belonged to a phylogenetic lineage defined by the

  14. Effects of different nitrogen forms, ammonia gas and wet deposited ammonium and nitrate, on methane and nitrous oxide emissions from an ombrotrophic bog, Whim Moss, in the Scottish Borders

    OpenAIRE

    Sheppard, L. J.; Leith, I. D.; Field, C.; van Dijk, N.; Rung, M.; Skiba, U.

    2008-01-01

    Enhanced reactive nitrogen deposition may compromise the sustainability and functioning of bogs, with respect to carbon sequestration and greenhouse gas production. Since 2002, three N forms have been applied to an ombrotrophic bog growing Calluna, Sphagnum capillifolium and Eriophorum vaginatum in order to test this. Significant changes in species cover and soil chemistry, especially in response to elevated ammonia concentrations, have been recorded. Ammonia deposition has also increased nit...

  15. Summertime greenhouse gas fluxes from an urban bog undergoing restoration through rewetting

    Directory of Open Access Journals (Sweden)

    A. Christen

    2016-04-01

    Full Text Available Rewetting can promote the ecological recovery of disturbed peatland ecosystems and may help to revert these ecosystems to carbon dioxide (CO2 sinks. However, rewetting of disturbed peatlands can also cause substantial emissions of methane (CH4 and possibly nitrous oxide (N2O. This study quantified summertime emissions of the three major long-lived greenhouse gases (GHGs CO2, CH4 and N2O; from undisturbed, disturbed and rewetted soils in the Burns Bog Ecological Conservancy Area (BBECA, a 20 km2 urban bog located in Delta, British Columbia, Canada. Four sites were chosen that represent different stages before or after ecological recovery in the BBECA: (i a relatively undisturbed scrub pine / Sphagnum / low shrub ecosystem; (ii a Rhynchospora alba / Sphagnum ecosystem that was disturbed by peat mining more than 65 years ago; (iii a R. alba / Dulichium arundinaceum ecosystem that was disturbed by peat mining 50 years ago and rewetted five years ago; and (iv a disturbed and rewetted surface with little vegetation cover that was cleared of vegetation 16 years ago and rewetted two years ago. The GHG fluxes from soils and ground vegetation were measured at all sites during June–August 2014, using a portable non-steady-state chamber system for CO2 and syringe sampling and laboratory analysis for CH4 and N2O fluxes. All four sites exhibited net GHG emissions into the atmosphere, dominated by CH4, which contributed 81–98 % of net CO2 equivalent (CO2e emissions. Overall, the median CH4 flux for all measurements and sites was ~74 mg m-2 day-1 (~30–410 mg m-2 day-1, 25th–75th percentiles. Fluxes in the rewetted (water-saturated sedge ecosystem were highest, with a quarter of the values higher than 3,000 mg m-2 day-1 (median 78 mg m-2 day-1. Exchange of CO2 due to photosynthesis and respiration was of secondary importance compared to soil CH4 emissions. Continuous CO2 flux measurements using the eddy covariance approach in the disturbed and rewetted R

  16. Unveiling exceptional Baltic bog ecohydrology, autogenic succession and climate change during the last 2000 years in CE Europe using replicate cores, multi-proxy data and functional traits of testate amoebae

    Science.gov (United States)

    Gałka, Mariusz; Tobolski, Kazimierz; Lamentowicz, Łukasz; Ersek, Vasile; Jassey, Vincent E. J.; van der Knaap, Willem O.; Lamentowicz, Mariusz

    2017-01-01

    We present the results of high-resolution, multi-proxy palaeoecological investigations of two parallel peat cores from the Baltic raised bog Mechacz Wielki in NE Poland. We aim to evaluate the role of regional climate and autogenic processes of the raised bog itself in driving the vegetation and hydrology dynamics. Based on partly synchronous changes in Sphagnum communities in the two study cores we suggest that extrinsic factors (climate) played an important role as a driver in mire development during the bog stage (500-2012 CE). Using a testate amoebae transfer function, we found exceptionally stable hydrological conditions during the last 2000 years with a relatively high water table and lack of local fire events that allowed for rapid peat accumulation (2.75 mm/year) in the bog. Further, the strong correlation between pH and community-weighted mean of testate amoeba traits suggests that other variables than water-table depth play a role in driving microbial properties under stable hydrological conditions. There is a difference in hydrological dynamics in bogs between NW and NE Poland until ca 1500 CE, after which the water table reconstructions show more similarities. Our results illustrate how various functional traits relate to different environmental variables in a range of trophic and hydrological scenarios on long time scales. Moreover, our data suggest a common regional climatic forcing in Mechacz Wielki, Gązwa and Kontolanrahka. Though it may still be too early to attempt a regional summary of wetness change in the southern Baltic region, this study is a next step to better understand the long-term peatland palaeohydrology in NE Europe.

  17. The sensitivity of Sphagnum to surface layer conditions in a re-wetted bog: a simulation study of water stress

    NARCIS (Netherlands)

    Schouwenaars, J.M.; Gosen, A.M.

    2007-01-01

    The behaviour of the water table in re-wetted bogs varies widely between different locations so that recolonising Sphagnum is vulnerable to water stress, especially when the water table is drawn down in summer. It is important to understand how physical site conditions influence the occurrence of

  18. Effect of nitrogen fertilization, grass species and cultivar on sod production on Valkeasuo peat bog - a case study

    Directory of Open Access Journals (Sweden)

    Perttu Virkajärvi

    1997-09-01

    Full Text Available As part of a research project concerning the agricultural utilization of cut-away peat bogs, a sod production experiment was conducted at Valkeasuo, Tohmajärvi, in 1990-1993. The aim of the experiment was to study the effect of nitrogen and choice of cultivar on sod production and sod quality on peat bogs. The N fertilization rates were 50, 100 and 150kg ha-1. The Poa pratensis cultivars were ‘Conni’, ‘Cynthia’, ‘Haga’ and ‘Julia’, the Festuca rubra cultivars were ‘Center’, ‘Juliska’, ‘Koket’ and ‘Näpsä’ and the Agrostis capillaris cultivar was ‘Rasti’. Two mixtures of P. pratensis/F. rubra and one of A. capillaris/F. rubra imitated commercial sod products. Increasing of N fertilization from 50 kg up to 150 kg ha-1 a had positive effect on general the quality of sod as well as on the green cover before and after transplanting. It increased the thatch formation. The positive effect of N on the number of tillers and green cover in the year following transplanting was dependent on the species and the cultivar. Species and cultivar affected all measured variables excluding thatch formation. Generally, the P. pratensis cultivars tested suited better for sod production than cultivars of F. rubra, but there were clear differences between cultivars within species as well. Although the soil was infertile, the contents of Ca, K, Mg, P, Cu, Fe, Mn, Mo and Zn in the herbage samples were within normal range. The botanical purity was high, which supports the hypothesis that the absence of seed bank of weeds on peat bogs immediately after harvesting the peat can be utilized.

  19. Net ecosystem exchange and energy fluxes measured with the eddy covariance technique in a western Siberian bog

    Directory of Open Access Journals (Sweden)

    P. Alekseychik

    2017-08-01

    Full Text Available Very few studies of ecosystem–atmosphere exchange involving eddy covariance data have been conducted in Siberia, with none in the western Siberian middle taiga. This work provides the first estimates of carbon dioxide (CO2 and energy budgets in a typical bog of the western Siberian middle taiga based on May–August measurements in 2015. The footprint of measured fluxes consisted of a homogeneous mixture of tree-covered ridges and hollows with the vegetation represented by typical sedges and shrubs. Generally, the surface exchange rates resembled those of pine-covered bogs elsewhere. The surface energy balance closure approached 100 %. Net CO2 uptake was comparatively high, summing up to 202 gC m−2 for the four measurement months, while the Bowen ratio was seasonally stable at 28 %. The ecosystem turned into a net CO2 source during several front passage events in June and July. The periods of heavy rain helped keep the water table at a sustainably high level, preventing a usual drawdown in summer. However, because of the cloudy and rainy weather, the observed fluxes might rather represent the special weather conditions of 2015 than their typical magnitudes.

  20. Carbon balance of a boreal bog during a year with an exceptionally dry summer

    Energy Technology Data Exchange (ETDEWEB)

    Alm, J.; Silvola, J. [Univ. of Joensuu (Finland). Dept. of Biology; Schulman, L. [Univ. of Helsinki (Finland). Dept. of Ecology and Systematics; Walden, J. [Finnish Meteorological Inst., Helsinki (Finland); Nykaenen, H.; Martikainen, P.J. [National Public Health Inst., Kuopio (Finland). Lab. of Environmental Microbiology

    1999-01-01

    Northern peatlands are important terrestrial carbon stores, and they show large spatial and temporal variation in the atmospheric exchange of CO{sub 2} and CH{sub 4}. Thus, annual carbon balance must be studied in detail in order to predict the climatic responses of these ecosystems. Closed-chamber methods were used to study CO{sub 2} and CH{sub 4} in hollow, Sphagnum angustifolium lawn. S. fuscum lawn, and hummock microsites within an ombrotrophic S. fuscum bog. Micrometeorological tower measurements were used as a reference for the CH{sub 3} efflux from the bog. Low precipitation during May--August in 1994 and a warm July--August period caused the water table to drop by more than 15 cm below the peat surface in the hollows and to 48 cm below the surface in high hummocks. Increased annual total respiration exceeded gross production and resulted in a net C loss of 4--157 g/m{sup 2} in the different microsites. Drought probably caused irreversible desiccation in some lawns of S. angustifolium and S. balticum and in S. fuscum in the hummocks, while S. balticum growing in hollows retained its moisture and even increased its photosynthetic capacity during the July--August period. Seasonal (12 May--4 October) CH{sub 4} emissions ranged from 2 g CH{sub 4}-C/m{sup 2} in drier S. fuscum hummocks and lawns to 7 and 14 g/m{sup 2} in wetter S. angustifolium-S. balticum lawns and hollows, respectively.

  1. Soil-to-plant transfer of 137Cs and 40K in an Atlantic blanket bog ecosystem

    International Nuclear Information System (INIS)

    Moran-Hunter, C.; O'Dea, J.

    2008-01-01

    The transfer of 137 Cs and 40 K from soil to vegetation was studied in an Atlantic blanket bog ecosystem along the Atlantic coast of Ireland where the dominant vegetation is a mixture of Calluna vulgaris, Eriophorum vaginatum and Sphagnum mosses. The impact of soil chemistry and nutritional status of vegetation on the uptake of both radionuclides was also examined. Cesium-137 transfer factors values ranged from 1.9 to 9.6 and accumulation of 137 Cs was higher in the leaves of C. vulgaris than in the stems. Transfer factors values for 137 Cs in both C. vulgaris and E. vaginatum were similar indicating that for the vegetation studied, uptake is not dependent on plant species. The uptake of 137 Cs in bog vegetation was found to be positively correlated with the nutrient status of vegetation, in particular the secondary nutrients, calcium and magnesium. Potassium-40 transfer factors ranged from 0.9 to 13.8 and uptake was higher in E. vaginatum than in C. vulgaris, however, unlike 137 Cs, the concentrations of 40 K within the leaves and stems of C. vulgaris were similar. The concentration of both 137 Cs and 40 K found in moss samples were in general lower than those found in vascular plants. (author)

  2. Sphagnum farming on cut-over bog in NW Germany: Long-term studies on Sphagnum growth

    Directory of Open Access Journals (Sweden)

    G. Gaudig

    2017-05-01

    Full Text Available Sphagnum farming allows sustainable and climate-friendly land use on bogs while producing a renewable substitute for peat in horticultural growing media. We studied Sphagnum productivity on an experimental Sphagnum culture established on a cut-over bog in Germany with strongly humified peat at the surface. Preparation of the site included levelling of the peat surface, construction of an irrigation system, spreading of Sphagnum papillosum fragments, covering them with straw, and finally rewetting. Provided there was an adequate (95 % initial cover of Sphagnum fragments, the most relevant variables for Sphagnum productivity were found to be water supply and regular mowing of vascular plants. As long as sufficient water was supplied, the dry biomass accumulation of the established Sphagnum lawn remained high, reaching 3.7 t ha-1 yr-1 between 2007 and 2011. Annual dry Sphagnum biomass productivity over the period 2010–2011 was up to 6.9 t ha-1. During periods when high water table could not be maintained, substantial decomposition of the previously accumulated biomass occurred. After nine years the net accumulated dry mass per hectare was on average 19.5 t of pure Sphagnum and 0.7 t of subsurface vascular-plant biomass. Nitrogen deposition in the study region is apparently sufficient to support fast Sphagnum growth, whereas phosphorus and potassium may be limiting.

  3. Ecoenzymatic stoichiometry and microbial processing of organic matter in northern bogs and fens reveals a common P limitation among peatland types

    Science.gov (United States)

    We compared C, N, and P concentrations in atmospheric deposition, runoff, and soil standing stocks with microbial respiration (DHA) and ecoenzyme activity (EEA) in an ombrotrophic bog (S2) and a minerotrophic fen (S3) to investigate the environmental drivers of biogeochemical cyc...

  4. Nitrogen and sulphur deposition and the growth of Sphagnum fuscum in bogs of the Athabasca Oil Sands Region, Alberta

    Directory of Open Access Journals (Sweden)

    Melanie A. VILE

    2010-08-01

    Full Text Available One of the consequences of ongoing development of the oil sands reserve in the Athabasca Oil Sands Region (AOSR near Fort McMurray, Alberta, Canada (56° 39' N, 111° 13' W is an increase in emissions of nitrogen (N and sulphur (S, with an attendant increases in regional atmospheric N and S deposition. Regional land cover across northeastern Alberta is a mixture of Boreal Mixedwood, Boreal Highlands, and Subarctic areas. Peatlands occupy between 22 and 66% of these natural regions, and the land cover of bogs varies between 6.7% in the Mixedwood Region to 46% in the Subarctic Region. Ombrotrophic bog ecosystems may be especially sensitive to atmospheric deposition of N and S. Across 10 ombrotrophic bog sites in the AOSR over four years (2005– 2008, we found no evidence of elevated deposition of NH4 +-N, NO3 –-N, total inorganic nitrogen (TIN; NH4 +-N plus NO3 –-N, or SO4 2–-S, with values measured using ion exchange resin collectors averaging 0.61 ± 04, 0.20 ± 0.01, 0.81 ± 0.04, and 1.14 ± 0.06 kg ha–1 y–1, respectively. Vertical growth and net primary production of Sphagnum fuscum, an indicator of elevated deposition, did not differ consistently across sites, averaging 11.8 ± 0.2 mm y–1 and 234 ± 3.3 g m–2 y–1, respectively, over the four years. Neither vertical growth nor net primary production of S. fuscum was correlated with growing season atmospheric N or S deposition. Our data provide a valuable benchmark of background values for monitoring purposes in anticipation of increasing N and S deposition over a broader geographic region within the AOSR.

  5. Non-destructive methods for peat layer assessment in oligotrophic peat bogs: a case study from Poiana Ştampei, Romania

    Directory of Open Access Journals (Sweden)

    Iuliana F. Gheorghe

    2011-01-01

    Full Text Available Practices currently employed in the investigation and characterisation of peat deposits are destructive and may irremediable perturb peat bog development even in cases when exploitation is not carried out. We investigated the correlation between vegetation characteristics in the active area of Poiana Ştampei peat bog, Romania, and the underlying peat layer depth, aiming at establishing a non-destructive method of peat layer depth estimation. The presence of the Sphagneto-Eriophoretum vaginati association, dominated by Sphagnum fimbriatum, Eriophorum vaginatum, Andromeda polifolia, Vaccinium oxycoccos, V. myrtillus, V. vitis-idaea, Polytrichum commune, Picea excelsa, Pinus sylvestris and Betula verrucosa was found to predict the existence of the peat layer but not its depth. Out of the seven identified vegetation types, one type was associated with a very thin or no peat layer, one type was characterised by the presence of a thick (over 100 cm peat layer and five types indicated the presence of variable average depths of the peat layer. pH values correlated with peat layer depth only within the vegetation type associated with thick peat layers.

  6. Many shades of brown : The condition and colour of Dutch archaeological textiles from dryland sandy soils, bogs, and the sea

    NARCIS (Netherlands)

    Joosten, I.; van Bommel, M.R.; Kluiving, S.; Kootker, L.; Hermans, R.

    2017-01-01

    Archaeological textiles excavated from Dutch soils usually have a brown appearance. Three sets of woollen textile finds varying both in age and burial context were analysed to study their original character. Bog finds from the Bronze Age (2000‑800 BC) and late Iron Age (250-12 BC) were compared to

  7. Changes of plant cover of the raised peat-bog Baligówka under the influence of human activity

    Directory of Open Access Journals (Sweden)

    Malec Magdalena

    2016-12-01

    Full Text Available The main purpose of the work was to determine the scope and degree of the influence of exploitation on changes of plant cover of the raised peat-bog Baligówka, located in the Orawsko- Nowotarska Valley. The analysis was carried out based on 47 phytosociological surveys using the Braun-Blanquet method. Results of investigations allow to state that excessive drying and fires that took place on the examined object caused wastage of many precious species of plants, especially from the Oxycocco- Sphagnetea class. Their place occupied species belonging to other classes, such as Nardo-Callunetea and Molinio-Arrhenatheretea. The basic cause of drying of the peat-bog and, in consequence, dying of peat formation species is intensified exploitation and connected with this drainage, carried out in the half of the 20th century. Unfortunately, local people up to now illegally have harvested the peat on the investigated object. Decrease in groundwater level leads to accelerated decay of peat, changes in physical and chemical properties of a substratum and, in consequence, changes in trophic values of habitat, what causes great changes in species composition of plant communities.

  8. Formation, succession and landscape history of Central-European summit raised bogs: A multiproxy study from the Hrubý Jeseník Mountains

    Czech Academy of Sciences Publication Activity Database

    Dudová, Lydie; Hájková, Petra; Buchtová, H.; Opravilová, V.

    2013-01-01

    Roč. 23, č. 2 (2013), s. 230-242 ISSN 0959-6836 R&D Projects: GA ČR GA206/08/0389 Institutional support: RVO:67985939 Keywords : bog succession * Larix * testate amoebae Subject RIV: EF - Botanics Impact factor: 3.794, year: 2013

  9. Ebullition, Plant-Mediated Transport, and Subsurface Horizontal Water Flow Dominate Methane Transport in an Arctic Sphagnum Bog

    Science.gov (United States)

    Wehr, R. A.; McCalley, C. K.; Logan, T. A.; Chanton, J.; Crill, P. M.; Rich, V. I.; Saleska, S. R.

    2017-12-01

    Emission of the greenhouse gas methane from wetlands is of prime concern in the prediction of climate change - especially emission associated with thawing permafrost, which may drive a positive feedback loop of emission and warming. In addition to the biochemistry of methane production and consumption, wetland methane emission depends critically on the transport mechanisms by which methane moves through and out of the ecosystem. We therefore developed a model of methane biochemistry and transport for a sphagnum bog representing an intermediate permafrost thaw stage in Stordalen Mire, Sweden. In order to simultaneously reproduce measured profiles of both the concentrations and isotopic compositions of both methane and carbon dioxide in the peat pore water (Fig. 1) - as well as the surface methane emission - it was necessary for the model to include ebullition, plant-mediated transport via aerenchyma, and subsurface horizontal water flow. Diffusion of gas through the pore water was relatively unimportant. As a result, 90% of the produced methane escaped the wetland rather than being consumed by methanotrophic organisms in the near-surface pore water. Our model provides a comprehensive picture of methane emission from this bog site by quantifying the vertical profiles of: acetoclastic methanogenesis, hydrogenotrophic methanogenesis, methane oxidation, aerobic respiration, ebullition, plant-mediated transport, subsurface horizontal water flow, and diffusion.

  10. Evaluation of heavy metal pollution in bogs of Tomsk region on change in biogeochemical activity of ericaceous shrubs

    Science.gov (United States)

    Gaskova, L. P.

    2018-01-01

    The article discusses the change in biogeochemical activity of plant species in bogs under the influence of various types of human impact (roads, cities, drainage of mires, fire). It has been established that ericaceous shrubs, depending on the species, react with varying degrees of intensity to anthropogenic influences. The biogeochemical activity of species increased by 2.5 to 4.8 times in polluted sites.

  11. Holocene climate variability in the western Mediterranean through a multiproxy analysis from Padul peat bog (Sierra Nevada, Spain)

    Science.gov (United States)

    Ramos-Román, María J.; Jiménez-Moreno, Gonzalo; Camuera, Jon; García-Alix, Antonio; Anderson, R. Scott; Jiménez-Espejo, Francisco J.; Sachse, Dirk

    2017-04-01

    The Iberian Peninsula, located in the Mediterranean area, is an interesting location for paleoclimate studies due to its geographic situation between arid and humid climates. Sediments from peat bogs and lakes from Sierra Nevada, in southeastern Iberian Peninsula, have been very informative in terms of how vegetation and wetland environments were impacted by Holocene climate change. These studies are essential if we want to understand the past climate change in the area, which is the key to identify the possible environmental response of the Sierra Nevada ecosystems to future climate scenarios. Padul basin, located in the southwest of the Sierra Nevada mountain range, contains a ca. 100 m-thick peat bog sedimentary sequence that was deposited during the past 1 Ma making this area interesting for paleoenvironmental and paleoclimatic reconstructions. A new 43 m-long sedimentary record has recently been retrieved from the Padul peat bog. In this study we have developed a multiproxy analysis of the Holocene part of the Padul-15-05 core including pollen analysis, XRF-core scanner, magnetic susceptibility and organic geochemistry, supported by an age control based on AMS radiocarbon dates, providing with information about vegetation and climate variability during the past 9.9 cal ka BP. This multiproxy reconstruction of the Padul-15-05 evidences the Mediterranean as a sensitive area with respect to global-scale climate system, showing relevant climate episodes such as the ca. 8, 7.5, 6.5 and 5.5 cal ka BP events during the early and middle Holocene. The trend to aridification to the late Holocene is interrupted by more arid and humid periods as the Iberian Roman Humid Period (from ca. 3 to 1.6 cal ka BP), the Dark Ages (from ca. 1.5 to 1.1 cal ka BP), the Medieval Climate Anomaly (from ca. 1.1 to 1.3 cal ka BP) and the Little Ice Age period (from ca. 500 to 100 cal yr BP).

  12. Denitrification at two nitrogen-polluted, ombrotrophic Sphagnum bogs in Central Europe: Insights from porewater N2O-isotope profiles

    Czech Academy of Sciences Publication Activity Database

    Novák, M.; Gebauer, G.; Thoma, M.; Curik, J.; Štěpánová, M.; Jacková, I.; Buzek, F.; Bárta, J.; Santrucková, H.; Fottová, D.; Kuběna, Aleš Antonín

    2015-01-01

    Roč. 81, č. 1 (2015), s. 48-57 ISSN 0038-0717 Grant - others:GA ČR(CZ) GAP504/12/1782 Institutional support: RVO:67985556 Keywords : Denitrification * Nitrogen isotopes * Nitrous oxide * Ombrotrophic bog * Porewater * Sphagnum * Wetland * Engineering controlled terms * Meteorological problems Subject RIV: DD - Geochemistry Impact factor: 4.152, year: 2015 http://library.utia.cas.cz/separaty/2015/E/kubena-0439538.pdf

  13. Ecoenzymatic stoichiometry and microbial processing of organic matter in northern bogs and fens reveals a common P-limitation between peatland types

    Science.gov (United States)

    Brian H. Hill; Colleen M. Elonen; Terri M. Jicha; Randall K. Kolka; LaRae L.P. Lehto; Stephen D. Sebestyen; Lindsey R. Seifert-Monson

    2014-01-01

    We compared carbon (C), nitrogen (N), and phosphorus (P) concentrations in atmospheric deposition, runoff, and soils with microbial respiration [dehydrogenase (DHA)] and ecoenzyme activity (EEA) in an ombrotrophic bog and a minerotrophic fen to investigate the environmental drivers of biogeochemical cycling in peatlands at the Marcell Experimental Forest in northern...

  14. Sphagnum restoration on degraded blanket and raised bogs in the UK using micropropagated source material: a review of progress

    Directory of Open Access Journals (Sweden)

    S.J.M Caporn

    2018-05-01

    Full Text Available There is a growing demand for a supply of Sphagnum to re-introduce to degraded peatlands. However, available supplies of Sphagnum of the desired species are often limited. We describe the propagation of Sphagnum from vegetative material in sterile tissue culture and the introduction of juvenile mosses into the field. Sphagnum produced in the laboratory in three different forms (beads, gel and plugs was introduced to different peatland surfaces on upland degraded blanket bog and lowland cut-over peatland in northern England. On degraded blanket bog, the establishment of mixed-species Sphagnum plugs was typically 99 % while the survival of beads was much lower, ranging from little above zero on bare eroding peat to a maximum of 12 % on stabilised peat surfaces. On lowland cut-over peatland, all trials took place on peat with an expanding cover of Eriophorum angustifolium and tested Sphagnum gel as well as beads and plugs. This work showed that survival and establishment of plugs was high (99 % and greater than for beads. Sphagnum gel reached a cover of 95 % in two years. The vegetative micropropagation of Sphagnum offers an effective source of Sphagnum for re-introduction to degraded peatlands.

  15. Pore-water indicators of rainwater-dominated versus groundwater-dominated peat bog profiles (Jura Mountains, Switzerland)

    International Nuclear Information System (INIS)

    Shotyk, W.; Steinmann, P.

    1994-01-01

    The dominant inorganic anions and cations, and dissolved organic carbon have been measured in the pore waters expressed from peat cores taken from two Sphagnum bogs in the Jura Mountains of Switzerland: Etang de la Gruyere (EGr) consists of > 6 m of peat representing more than 12,000 yr of peat formation while at La Tourbiere de Genevez (TGe) approximately 1.5 m of peat have accumulated over the past 5,000 yr. The pore-water analyses of the core taken at EGr show that the first 100 cm of the core are influenced only by atmospheric inputs. Relative to the average composition of rainwater in this area, Na + is enriched throughout the pore-water profiles, K 2+ is neither enriched nor depleted, Mg 2+ is significantly depleted in the deeper pore waters and Ca 2+ strongly depleted through the profile. The dominant process affecting the cations in these waters is ion exchange, with the peats behaving like a simple cation exchanger with ion preference decreasing in the order Ca 2+ >Mg 2+ >H + >K + much-greater than Na + . In contrast, at TGe the pH increases from pH approximately 4 at the surface to pH 5 at 80 cm. The Cl - and K + concentrations are up to 10 times higher than rainwater values because of mixing of the bog pore water with nearby groundwaters. The Mg 2+ and Ca 2+ concentrations increase with depth to concentrations up to 10 times higher than rainwater values, mainly because of the increasing importance of mineral dissolution within the profile

  16. Thermokarst in pingos and adjacent collapse scar bogs in interior Alaska

    Science.gov (United States)

    Douglas, T. A.; Turetsky, M. R.

    2017-12-01

    A region of discontinuous permafrost 50 kilometers southeast of Fairbanks, Alaska exhibits rapid thermokarst and landscape change. The area contains a dozen pingos (hydrolaccoliths), mounds of ice covered by earth material typically 100 meters across and 20 meters above the surrounding ground surface. The pingos have sunken craters in their centers formed through melting and collapse of an inner ice lens core. Adjacent to the pingos are collapse scar bogs in various states of formation and ice wedge terrain undergoing thaw subsidence to polygons and thermokarst mounds (baydzherakhs). With a mean annual temperature of -1 degree C the area contains warm ecosystem-protected permafrost vulnerable to thaw. We analyzed historical imagery to the 1970s to track water features in a subset of pingos. The craters have expanded over the past few decades suggesting melting and collapse of the ice cored center and potential permafrost degradation along pingo margins. Collapse scar bogs in adjacent low-elevation terrain are roughly the same size as the pingos but have little vertical elevation gradient compared to the surrounding terrain. Electrical resistivity tomography (ERT) measurements, high resolution GPS surveys, SIPRE coring, and thaw depth probing were focused along nine 400 meter transects across three of the pingos to identify relationships between geophysical properties, permafrost composition, seasonal thaw, and ecological state. A large ( 40 meters across and 20 meters thick) lens shaped region of thawed permafrost is evident in the ERT results about 10 meters below the ground surface in the center of one pingo we surveyed in detail. This is believed to be the original ice cored region of the pingo that has melted. A thin (1-5 meters thick) layer of permafrost is present above this thawed region while the rampart margins surrounding the pingo are underlain by thick (10-30 m) permafrost. The pingo and thermokarst features reside in a location where rapid permafrost

  17. Nutrient cycling and productivity of dystrophic lake-bog systems (Part A). Technical progress report, December 1, 1972--September 30, 1975

    International Nuclear Information System (INIS)

    Hooper, F.F.

    1975-10-01

    A sampler and an analytical and characterization scheme were developed to investigate the chemical and physical state of iron in a highly stained acid bog lake. Iron fractions were chemically separated by reactivity to bathophenanthroline (BPN) after specific digestion procedures. Physical separation involved anaerobic in situ filtration (450 nm), and in situ dialysis (4.8 nm). This resulted in three size classes: particulate, colloidal, and dissolved. Unlike pH 6-8 lakes, inorganic, nonreactive species of iron [e.g., Fe(OH) 3 ] represent minor amounts of the total iron in North Gate Lake. In situ radiochemical analyses revealed that colloidal sized reactive ferric iron predominates in the oxygenated epilimnion, while dialyzable or dissolved ferrous iron increases with depth. Unlike iron, organic matter is present in a nontransient colloidal state. In acid (pH 4-5) bog lakes ferric iron is not colloidal as an inorganic complex (OH - ), but colloidal as reactive Fe + 3 by complexation with the colloidal organic acids. After thermally induced mixing with anaerobic waters, ferric iron is reduced and dissolved. However, some of the BPN reactive iron remains colloidal suggesting the presence of a residual ferrous organic complex

  18. Concepts of fen and bog re-examined in relation to bryophyte cover and the acidity of surface waters

    OpenAIRE

    Eville Gorham; Jan A. Janssens

    2014-01-01

    Studies of surface-water pH and bryophyte assemblages in 440 plots from five peatland regions across northern North America reveal a very distinct, two-fold division into fens with a pH mode at 6.76-7.00, in which Amblystegiaceae are prominent, and bogs with a pH mode at 4.01-4.25, in which Sphagnaceae are dominant. The relevance of the data to past and current views on peatland classification is explored.

  19. Concepts of fen and bog re-examined in relation to bryophyte cover and the acidity of surface waters

    Directory of Open Access Journals (Sweden)

    Eville Gorham

    2014-01-01

    Full Text Available Studies of surface-water pH and bryophyte assemblages in 440 plots from five peatland regions across northern North America reveal a very distinct, two-fold division into fens with a pH mode at 6.76-7.00, in which Amblystegiaceae are prominent, and bogs with a pH mode at 4.01-4.25, in which Sphagnaceae are dominant. The relevance of the data to past and current views on peatland classification is explored.

  20. Genetic population structure of the vulnerable bog fritillary butterfly.

    Science.gov (United States)

    Vandewoestijne, S; Baguette, M

    2004-01-01

    Populations of the bog fritillary butterfly Proclossiana eunomia (Lepidoptera, Nymphalidae) occur in patchy habitat in central and western Europe. P. eunomia is a vulnerable species in the Belgian Ardennes and the number of occupied sites has significantly decreased in this region since the 1960s. RAPD (random amplified polymorphic DNA) markers were used to study the consequences of habitat loss and fragmentation on the genetic population structure of this species. Gene diversity was lower in populations with smaller population sizes. Genetic subdivision was high (Fst=0.0887) considering the small spatial scale of this study (150 km2). The most geographically isolated population was also the most genetically differentiated one. The genetic population structure and genetic differentiation detected in this study were explained by (1) differences in altitude of the sampled locations and, (2) lower dispersal propensity and dispersal rate in fragmented landscapes versus continuous landscapes. Results from the RAPD analyses were compared with a previous allozyme based study on the same populations. The results of this study suggest that increased fragmentation has lead to a greater genetic differentiation between remaining P. eunomia populations.

  1. Impact of two hot and dry summers on the community structure and functional diversity of testate amoebae in an artificial bog, illustrating their use as bioindicators of peatland health

    Directory of Open Access Journals (Sweden)

    I. Koenig

    2018-04-01

    Full Text Available Ongoing climate warming threatens the survival of bogs at the warm/dry limit of their distribution (e.g. in central Europe, and jeopardises the restoration of damaged bogs even more. Because vegetation changes can be slow, early indicators of hydrological change such as testate amoebae are useful. We used testate amoeba community structure and community weighted mean of functional traits to monitor the impact of two very hot and dry summers on a small (around 100 m2 artificial peatland constructed in the botanic garden of Neuchâtel, Switzerland. We collected analogous samples in a naturally regenerating cutover peatland at 1000 m a.s.l. in the Jura Mountains as a reference. The comparison of living and dead assemblages in the botanic garden showed an increased representation of smaller testate amoeba taxa (Corythion dubium, small Euglypha sp. with a small pseudostome (indicative of dry conditions and a loss of mixotrophy in 2015, followed by a weaker further shift in 2016. Nevertheless, the testate amoeba community structure in 2016 still indicated a dry Sphagnum bog. Testate amoeba analysis allows rapid assessment of peatland health and/or restoration success. The comparison of living and dead assemblages makes it possible to observe changes within a season in a single sampling campaign.

  2. Contrasting species-environment relationships in communities of testate amoebae, bryophytes and vascular plants along the fen-bog gradient.

    Science.gov (United States)

    Lamentowicz, Mariusz; Lamentowicz, Lukasz; van der Knaap, Willem O; Gabka, Maciej; Mitchell, Edward A D

    2010-04-01

    We studied the vegetation, testate amoebae and abiotic variables (depth of the water table, pH, electrical conductivity, Ca and Mg concentrations of water extracted from mosses) along the bog to extremely rich fen gradient in sub-alpine peatlands of the Upper Engadine (Swiss Alps). Testate amoeba diversity was correlated to that of mosses but not of vascular plants. Diversity peaked in rich fen for testate amoebae and in extremely rich fen for mosses, while for testate amoebae and mosses it was lowest in bog but for vascular plants in extremely rich fen. Multiple factor and redundancy analyses (RDA) revealed a stronger correlation of testate amoebae than of vegetation to water table and hydrochemical variables and relatively strong correlation between testate amoeba and moss community data. In RDA, hydrochemical variables explained a higher proportion of the testate amoeba and moss data than water table depth. Abiotic variables explained a higher percentage of the species data for testate amoebae (30.3% or 19.5% for binary data) than for mosses (13.4%) and vascular plants (10%). These results show that (1) vascular plant, moss and testate amoeba communities respond differently to ecological gradients in peatlands and (2) testate amoebae are more strongly related than vascular plants to the abiotic factors at the mire surface. These differences are related to vertical trophic gradients and associated niche differentiation.

  3. High methane emissions dominate annual greenhouse gas balances 30 years after bog rewetting

    Science.gov (United States)

    Vanselow-Algan, M.; Schmidt, S. R.; Greven, M.; Fiencke, C.; Kutzbach, L.; Pfeiffer, E.-M.

    2015-02-01

    Natural peatlands are important carbon sinks and sources of methane (CH4). In contrast, drained peatlands turn from a carbon sink to a carbon source and potentially emit nitrous oxide (N2O). Rewetting of peatlands thus implies climate change mitigation. However, data about the time span that is needed for the re-establishment of the carbon sink function by restoration is scarce. We therefore investigated the annual greenhouse gas (GHG) balances of three differently vegetated bog sites 30 years after rewetting. All three vegetation communities turned out to be sources of carbon dioxide (CO2) ranging between 0.6 ± 1.43 t CO2 ha-2 yr-1 (Sphagnum-dominated vegetation) and 3.09 ± 3.86 t CO2 ha-2 yr-1 (vegetation dominated by heath). While accounting for the different global warming potential (GWP) of the three greenhouse gases, the annual GHG balance was calculated. Emissions ranged between 25 and 53 t CO2-eq ha-1 yr-1 and were dominated by large emissions of CH4 (22 up to 51 t CO2-eq ha-1 yr-1), while highest rates were found at purple moor grass (Molinia caerulea) stands. These are to our knowledge the highest CH4 emissions so far reported for bog ecosystems in temperate Europe. As the restored area was subject to large fluctuations in water table, we conclude that the high CH4 emission rates were caused by a combination of both the temporal inundation of the easily decomposable plant litter of this grass species and the plant-mediated transport through its tissues. In addition, as a result of the land use history, the mixed soil material can serve as an explanation. With regards to the long time span passed since rewetting, we note that the initial increase in CH4 emissions due to rewetting as described in the literature is not limited to a short-term period.

  4. High methane emissions dominated annual greenhouse gas balances 30 years after bog rewetting

    Science.gov (United States)

    Vanselow-Algan, M.; Schmidt, S. R.; Greven, M.; Fiencke, C.; Kutzbach, L.; Pfeiffer, E.-M.

    2015-07-01

    Natural peatlands are important carbon sinks and sources of methane (CH4). In contrast, drained peatlands turn from a carbon sink to a carbon source and potentially emit nitrous oxide (N2O). Rewetting of peatlands thus potentially implies climate change mitigation. However, data about the time span that is needed for the re-establishment of the carbon sink function by restoration are scarce. We therefore investigated the annual greenhouse gas (GHG) balances of three differently vegetated sites of a bog ecosystem 30 years after rewetting. All three vegetation communities turned out to be sources of carbon dioxide (CO2) ranging between 0.6 ± 1.43 t CO2 ha-2 yr-1 (Sphagnum-dominated vegetation) and 3.09 ± 3.86 t CO2 ha-2 yr-1 (vegetation dominated by heath). While accounting for the different global warming potential (GWP) of CO2, CH4 and N2O, the annual GHG balance was calculated. Emissions ranged between 25 and 53 t CO2-eq ha-1 yr-1 and were dominated by large emissions of CH4 (22-51 t CO2-eq ha-1 yr-1), with highest rates found at purple moor grass (Molinia caerulea) stands. These are to our knowledge the highest CH4 emissions so far reported for bog ecosystems in temperate Europe. As the restored area was subject to large fluctuations in the water table, we assume that the high CH4 emission rates were caused by a combination of both the temporal inundation of the easily decomposable plant litter of purple moor grass and the plant-mediated transport through its tissues. In addition, as a result of the land use history, mixed soil material due to peat extraction and refilling can serve as an explanation. With regards to the long time span passed since rewetting, we note that the initial increase in CH4 emissions due to rewetting as described in the literature is not inevitably limited to a short-term period.

  5. Nutrient Addition Leads to a Weaker CO2 Sink and Higher CH4 Emissions through Vegetation-Microclimate Feedbacks at Mer Bleue Bog, Canada

    Science.gov (United States)

    Bubier, J. L.; Arnkil, S.; Humphreys, E.; Juutinen, S.; Larmola, T.; Moore, T. R.

    2015-12-01

    Atmospheric nitrogen (N) deposition has led to nutrient enrichment in wetlands globally, affecting plant community composition, carbon (C) cycling, and microbial dynamics. Nutrient-limited boreal bogs are long-term sinks of carbon dioxide (CO2), but sources of methane (CH4), an important greenhouse gas. We fertilized Mer Bleue Bog, a Sphagnum moss and evergreen shrub-dominated ombrotrophic bog near Ottawa, Ontario, for 10-15 years with N as NO3 and NH4 at 5, 10 and 20 times ambient N deposition (0.6-0.8 g N m-2 y-1), with and without phosphorus (P) and potassium (K). Treatments were applied to triplicate plots (3 x 3 m) from May - August 2000-2015 and control plots received distilled water. We measured net ecosystem CO2 exchange (NEE), ecosystem photosynthesis and respiration, and CH4 flux with climate-controlled chambers; leaf-level CO2 exchange and biochemistry; substrate-induced respiration, CH4 production and consumption potentials with laboratory incubations; plant species composition and abundance; and microclimate (peat temperature, moisture, light interception). After 15 years, we have found that NEE has decreased, and CH4 emissions have increased, in the highest nutrient treatments owing to changes in vegetation, microtopography, and peat characteristics. Vegetation changes include a loss of Sphagnum moss and introduction of new deciduous species. Simulated atmospheric N deposition has not benefitted the photosynthetic apparatus of the dominant evergreen shrubs, but resulted in higher foliar respiration, contributing to a weaker ecosystem CO2 sink. Loss of moss has led to wetter near-surface substrate, higher rates of decomposition and CH4 emission, and a shift in microbial communities. Thus, elevated atmospheric deposition of nutrients may endanger C storage in peatlands through a complex suite of feedbacks and interactions among vegetation, microclimate, and microbial communities.

  6. Flourish or flush: effects of simulated extreme rainfall events on Sphagnum-dwelling testate amoebae in a subarctic bog (Abisko, Sweden).

    Science.gov (United States)

    Tsyganov, Andrey N; Keuper, Frida; Aerts, Rien; Beyens, Louis

    2013-01-01

    Extreme precipitation events are recognised as important drivers of ecosystem responses to climate change and can considerably affect high-latitude ombrotrophic bogs. Therefore, understanding the relationships between increased rainfall and the biotic components of these ecosystems is necessary for an estimation of climate change impacts. We studied overall effects of increased magnitude, intensity and frequency of rainfall on assemblages of Sphagnum-dwelling testate amoebae in a field climate manipulation experiment located in a relatively dry subarctic bog (Abisko, Sweden). The effects of the treatment were estimated using abundance, species diversity and structure of living and empty shell assemblages of testate amoebae in living and decaying layers of Sphagnum. Our results show that increased rainfall reduced the mean abundance and species richness of living testate amoebae. Besides, the treatment affected species structure of both living and empty shell assemblages, reducing proportions of hydrophilous species. The effects are counterintuitive as increased precipitation-related substrate moisture was expected to have opposite effects on testate amoeba assemblages in relatively dry biotopes. Therefore, we conclude that other rainfall-related factors such as increased infiltration rates and frequency of environmental disturbances can also affect testate amoeba assemblages in Sphagnum and that hydrophilous species are particularly sensitive to variation in these environmental variables.

  7. Holocene vegetation and climate change recorded in alpine bog sediments from the Borreguiles de la Virgen, Sierra Nevada, southern Spain

    Science.gov (United States)

    Jiménez-Moreno, Gonzalo; Anderson, R. Scott

    2012-01-01

    High-resolution pollen and magnetic susceptibility (MS) analyses have been carried out on a sediment core taken from a high-elevation alpine bog area located in Sierra Nevada, southern Spain. The earliest part of the record, from 8200 to about 7000 cal yr BP, is characterized by the highest abundance of arboreal pollen and Pediastrum, indicating the warmest and wettest conditions in the area at that time. The pollen record shows a progressive aridification since 7000 cal yr BP that occurred in two steps, first shown by a decrease in Pinus, replaced by Poaceae from 7000 to 4600 cal yr BP and then by Cyperaceae, Artemisia and Amaranthaceae from 4600 to 1200 cal yr BP. Pediastrum also decreased progressively and totally disappeared at ca. 3000 yr ago. The progressive aridification is punctuated by periodically enhanced drought at ca. 6500, 5200 and 4000 cal yr BP that coincide in timing and duration with well-known dry events in the Mediterranean and other areas. Since 1200 cal yr BP, several changes are observed in the vegetation that probably indicate the high-impact of humans in the Sierra Nevada, with pasturing leading to nutrient enrichment and eutrophication of the bog, Pinus reforestation and Olea cultivation at lower elevations.

  8. Differential effects of high atmospheric N and S deposition on bog plant/lichen tissue and porewater chemistry across the Athabasca Oil Sands Region

    Science.gov (United States)

    R. Kelman Wieder; Melanie A. Vile; Kimberli D. Scott; Cara M. Albright; Kelly J. McMillen; Dale H. Vitt; Mark E. Fenn

    2016-01-01

    Oil extraction and development activities in the Athabasca Oil Sands Region of northern Alberta, Canada, release NOx, SOx, and NHy to the atmosphere, ultimately resulting in increasing N and S inputs to surrounding ecosystems through atmospheric deposition. Peatlands are a major feature of the northern Alberta landscape, with bogs covering 6-10% of the land area, and...

  9. Antioxidant properties, phenolic composition and potentiometric sensor array evaluation of commercial and new blueberry (Vaccinium corymbosum) and bog blueberry (Vaccinium uliginosum) genotypes.

    Science.gov (United States)

    Kraujalytė, Vilma; Venskutonis, Petras Rimantas; Pukalskas, Audrius; Česonienė, Laima; Daubaras, Remigijus

    2015-12-01

    Antioxidant properties of juices of newly bred and known blueberry (Vaccinium corymbosum) genotypes and wild bog blueberry (Vaccinium uliginosum) were evaluated by ABTS(+) scavenging capacity (RSC), ferric reducing antioxidant power (FRAP), oxygen radical absorbance capacity (ORAC), total phenolic content (TPC) and total anthocyanin content (TAC) assays. TPC varied in the range of 0.85-2.81 mg gallic acid equiv./mL, RSC, FRAP and ORAC values were 6.38-20.9, 3.07-17.8 and 4.21-45.68 μmol Trolox equiv./g, respectively. New blueberry genotypes and bog blueberry demonstrated stronger antioxidant properties and TAC than other studied genotypes. The content of quinic (203-3614 μg/mL), chlorogenic (20.0-346.8 μg/mL) acids and rutin (0.00-26.88 μg/mL) measured by UPLC/ESI-QTOF-MS varied depending on the genotype. Juices were evaluated by electronic tongue; PCA score plot showed that the method discriminates different genotypes although some juice samples were located very closely and overlapping. Significant differences were observed between L(∗), a(∗), b(∗) colour parameters of some genotypes. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. Sphagnum-dwelling testate amoebae in subarctic bogs are more sensitive to soil warming in the growing season than in winter: the results of eight-year field climate manipulations.

    Science.gov (United States)

    Tsyganov, Andrey N; Aerts, Rien; Nijs, Ivan; Cornelissen, Johannes H C; Beyens, Louis

    2012-05-01

    Sphagnum-dwelling testate amoebae are widely used in paleoclimate reconstructions as a proxy for climate-induced changes in bogs. However, the sensitivity of proxies to seasonal climate components is an important issue when interpreting proxy records. Here, we studied the effects of summer warming, winter snow addition solely and winter snow addition together with spring warming on testate amoeba assemblages after eight years of experimental field climate manipulations. All manipulations were accomplished using open top chambers in a dry blanket bog located in the sub-Arctic (Abisko, Sweden). We estimated sensitivity of abundance, diversity and assemblage structure of living and empty shell assemblages of testate amoebae in the living and decaying layers of Sphagnum. Our results show that, in a sub-arctic climate, testate amoebae are more sensitive to climate changes in the growing season than in winter. Summer warming reduced species richness and shifted assemblage composition towards predominance of xerophilous species for the living and empty shell assemblages in both layers. The higher soil temperatures during the growing season also decreased abundance of empty shells in both layers hinting at a possible increase in their decomposition rates. Thus, although possible effects of climate changes on preservation of empty shells should always be taken into account, species diversity and structure of testate amoeba assemblages in dry subarctic bogs are sensitive proxies for climatic changes during the growing season. Copyright © 2011 Elsevier GmbH. All rights reserved.

  11. Mycobacterium minnesotense sp. nov., a photochromogenic bacterium isolated from sphagnum peat bogs.

    Science.gov (United States)

    Hannigan, Geoffrey D; Krivogorsky, Bogdana; Fordice, Daniel; Welch, Jacqueline B; Dahl, John L

    2013-01-01

    Several intermediate-growing, photochromogenic bacteria were isolated from sphagnum peat bogs in northern Minnesota, USA. Acid-fast staining and 16S rRNA gene sequence analysis placed these environmental isolates in the genus Mycobacterium, and colony morphologies and PCR restriction analysis patterns of the isolates were similar. Partial sequences of hsp65 and dnaJ1 from these isolates showed that Mycobacterium arupense ATCC BAA-1242(T) was the closest mycobacterial relative, and common biochemical characteristics and antibiotic susceptibilities existed between the isolates and M. arupense ATCC BAA-1242(T). However, compared to nonchromogenic M. arupense ATCC BAA-1242(T), the environmental isolates were photochromogenic, had a different mycolic acid profile and had reduced cell-surface hydrophobicity in liquid culture. The data reported here support the conclusion that the isolates are representatives of a novel mycobacterial species, for which the name Mycobacterium minnesotense sp. nov. is proposed. The type strain is DL49(T) (=DSM 45633(T) = JCM 17932(T) = NCCB 100399(T)).

  12. Major and trace elements in Sphagnum moss from four southern German bogs, and comparison with available moss monitoring data

    OpenAIRE

    KEMPTER HEIKE; KRACHLER MICHAEL; SHOTYK W.; ZACCONE CLAUDIO

    2017-01-01

    In this paper, we present concentrations of an array of major and trace elements (Ag, Al, As, Ba, Bi, Cd, Co, Cr, Cu, Fe, Mn, Mo, Rb, Sb, Sc, Sr, Th, Tl, U, V, Zn) in living Sphagnum mosses from four southern German bogs and compare them with moss monitoring data of the respective regions. To do this, Sphagnum mosses were collected in Upper Bavaria (Oberbayern, OB) and the Northern Black Forest (Nordschwarzwald, NBF). Surfaces of Sphagnum carpets were marked with plastic mesh and, one year la...

  13. Sphagnum mosses from 21 ombrotrophic bogs in the athabasca bituminous sands region show no significant atmospheric contamination of "heavy metals".

    Science.gov (United States)

    Shotyk, William; Belland, Rene; Duke, John; Kempter, Heike; Krachler, Michael; Noernberg, Tommy; Pelletier, Rick; Vile, Melanie A; Wieder, Kelman; Zaccone, Claudio; Zhang, Shuangquan

    2014-11-04

    Sphagnum moss was collected from 21 ombrotrophic (rain-fed) peat bogs surrounding open pit mines and upgrading facilities of Athabasca bituminous sands in Alberta (AB). In comparison to contemporary Sphagnum moss from four bogs in rural locations of southern Germany (DE), the AB mosses yielded lower concentrations of Ag, Cd, Ni, Pb, Sb, and Tl, similar concentrations of Mo, but greater concentrations of Ba, Th, and V. Except for V, in comparison to the "cleanest", ancient peat samples ever tested from the northern hemisphere (ca. 6000-9000 years old), the concentrations of each of these metals in the AB mosses are within a factor of 3 of "natural, background" values. The concentrations of "heavy metals" in the mosses, however, are proportional to the concentration of Th (a conservative, lithophile element) and, therefore, contributed to the plants primarily in the form of mineral dust particles. Vanadium, the single most abundant trace metal in bitumen, is the only anomaly: in the AB mosses, V exceeds that of ancient peat by a factor of 6; it is therefore enriched in the mosses, relative to Th, by a factor of 2. In comparison to the surface layer of peat cores collected in recent years from across Canada, from British Columbia to New Brunswick, the Pb concentrations in the mosses from AB are far lower.

  14. High specificity but contrasting biodiversity of Sphagnum-associated bacterial and plant communities in bog ecosystems independent of the geographical region.

    Science.gov (United States)

    Opelt, Katja; Berg, Christian; Schönmann, Susan; Eberl, Leo; Berg, Gabriele

    2007-10-01

    Mosses represent ecological niches that harbor a hitherto largely uncharacterized microbial diversity. To investigate which factors affect the biodiversity of bryophyte-associated bacteria, we analyzed the bacterial communities associated with two moss species, which exhibit different ecological behaviors and importance in bog ecosystems, Sphagnum magellanicum and Sphagnum fallax, from six temperate and boreal bogs in Germany and Norway. Furthermore, their surrounding plant communities were studied. Molecular analysis of bacterial communities was determined by single-strand conformation polymorphism (SSCP) analysis using eubacterial and genus-specific primers for the dominant genera Burkholderia and Serratia as well as by sequence analysis of a Burkholderia 16S rRNA gene clone library. Plant communities were analyzed by monitoring the abundance and composition of bryophyte and vascular plant species, and by determining ecological indicator values. Interestingly, we found a high degree of host specificity for associated bacterial and plant communities of both Sphagnum species independent of the geographical region. Calculation of diversity indices on the basis of SSCP gels showed that the S. fallax-associated communities displayed a statistically significant higher degree of diversity than those associated with S. magellanicum. In contrast, analyses of plant communities of Sphagnum-specific habitats resulted in a higher diversity of S. magellanicum-specific habitats for all six sites. The higher content of nutrients in the S. fallax-associated ecosystems can explain higher diversity of microorganisms.

  15. Performing Translation as Practice-led Research: The Case of Carr’s “By the Bog of Cats…” in Brazil

    OpenAIRE

    Alinne Balduino P. Fernandes

    2015-01-01

    This article offers a retrospective analysis of aspects of my translation for the stage of Marina Carr’s By the Bog of Cats… into Brazilian Portuguese. By focusing on the iterative aspects of theatre translation as well as the translation of dialect, this article will elaborate the notion that theatre translation takes place at both individual and collaborative levels in which the translator works in dramaturgical capacity. These two levels cannot be dissociated because they constantly inf...

  16. Sphagnum-dwelling testate amoebae in subarctic bogs are more sensitive to soil warming in the growing season than in winter: the results of eight-year field climate manipulations.

    NARCIS (Netherlands)

    Tsyganov, A.N.; Aerts, R.; Nijs, I.; Cornelissen, J.H.C.; Beyens, L.

    2012-01-01

    Sphagnum-dwelling testate amoebae are widely used in paleoclimate reconstructions as a proxy for climate-induced changes in bogs. However, the sensitivity of proxies to seasonal climate components is an important issue when interpreting proxy records. Here, we studied the effects of summer warming,

  17. Dynamics of biochemical processes and redox conditions in geochemically linked landscapes of oligotrophic bogs

    Science.gov (United States)

    Inisheva, L. I.; Szajdak, L.; Sergeeva, M. A.

    2016-04-01

    The biological activity in oligotrophic peatlands at the margins of the Vasyugan Mire has been studied. It is shown found that differently directed biochemical processes manifest themselves in the entire peat profile down to the underlying mineral substrate. Their activity is highly variable. It is argued that the notion about active and inert layers in peat soils is only applicable for the description of their water regime. The degree of the biochemical activity is specified by the physical soil properties. As a result of the biochemical processes, a micromosaic aerobic-anaerobic medium is developed under the surface waterlogged layer of peat deposits. This layer contains the gas phase, including oxygen. It is concluded that the organic and mineral parts of peat bogs represent a single functional system of a genetic peat profile with a clear record of the history of its development.

  18. Chromobacterium sphagni sp. nov., an insecticidal bacterium isolated from Sphagnum bogs.

    Science.gov (United States)

    Blackburn, Michael B; Farrar, Robert R; Sparks, Michael E; Kuhar, Daniel; Mitchell, Ashaki; Gundersen-Rindal, Dawn E

    2017-09-01

    Sixteen isolates of Gram-reaction-negative, motile, violet-pigmented bacteria were isolated from Sphagnum bogs in West Virginia and Maine, USA. 16S rRNA gene sequences and fatty acid analysis revealed a high degree of relatedness among the isolates, and genome sequencing of two isolates, IIBBL 14B-1T and IIBBL 37-2 (from West Virginia and Maine, respectively), revealed highly similar genomic sequences. The average nucleotide identity (gANI) calculated for these two isolates was found to be in excess of 99 %, but did not exceed 88 % when comparing either isolate with genomic sequences of Chromobacterium violaceum ATCC 12472T, C. haemolyticum DSM 19808T, C. piscinae ND17, C. subtsugae PRAA4-1T, C. vaccinii MWU205T or C. amazonense CBMAI 310T. Collectively, gANI and 16S rRNA gene sequence comparisons suggested that isolates IIBBL 14B-1T and IIBBL 37-2 were most closely related to C. subtsugae, but represented a distinct species. We propose the name Chromobacterium sphagni sp. nov. for this taxon; the type strain is IIBBL 14B-1T (=NRRL B-67130T=JCM 31882T).

  19. Intercomparison of radiocarbon bomb pulse and 210Pb age models. A study in a peat bog core from North Poland

    International Nuclear Information System (INIS)

    Piotrowska, Natalia; Vleeschouwer, Francois De; Sikorski, Jaroslaw; Pawlyta, Jacek; Fagel, Nathalie; Roux, Gael Le; Pazdur, Anna

    2010-01-01

    Radiocarbon and 210 Pb were measured on the uppermost 40 cm of a Wardenaar peat core retrieved from a Baltic raised bog at Slowinskie Blota (Pomerania, North Poland). This site is the subject of ongoing multiproxy studies covering the last 1300 years. Radiocarbon age model was constructed on the basis of 14 AMS dates obtained on selected Sphagnum spp. fragments, with use of P S equence tool. We present here a comparison of this model with the age model obtained using CRS model classically applied to 210 Pb measurements.

  20. Intercomparison of radiocarbon bomb pulse and 210Pb age models. A study in a peat bog core from North Poland

    Science.gov (United States)

    Piotrowska, Natalia; De Vleeschouwer, François; Sikorski, Jarosław; Pawlyta, Jacek; Fagel, Nathalie; Le Roux, Gaël; Pazdur, Anna

    2010-04-01

    Radiocarbon and 210Pb were measured on the uppermost 40 cm of a Wardenaar peat core retrieved from a Baltic raised bog at Słowińskie Błota (Pomerania, North Poland). This site is the subject of ongoing multiproxy studies covering the last 1300 years. Radiocarbon age model was constructed on the basis of 14 AMS dates obtained on selected Sphagnum spp. fragments, with use of P_Sequence tool. We present here a comparison of this model with the age model obtained using CRS model classically applied to 210Pb measurements.

  1. Atmospheric lead and heavy metal pollution records from a Belgian peat bog spanning the last two millenia: Human impact on a regional to global scale

    Energy Technology Data Exchange (ETDEWEB)

    Vleeschouwer, Francois de [URAP, Departement de Geologie, Universite de Liege, Allee du 6 Aout B18 Sart Tilman B4000 - Liege (Belgium)]. E-mail: fdevleeschouwer@student.ulg.ac.be; Gerard, Laetitia [URAP, Departement de Geologie, Universite de Liege, Allee du 6 Aout B18 Sart Tilman B4000 - Liege (Belgium); Goormaghtigh, Catherine [Unite de recherche: ' Isotopes, Petrologie et Environnement' , Departement des Sciences de la Terre et de l' Environnement, CP 160/02 Universite Libre de Bruxelles, Avenue FD. Roosevelt, 50, B-1050 Bruxelles (Belgium); Mattielli, Nadine [Unite de recherche: ' Isotopes, Petrologie et Environnement' , Departement des Sciences de la Terre et de l' Environnement, CP 160/02 Universite Libre de Bruxelles, Avenue FD. Roosevelt, 50, B-1050 Bruxelles (Belgium); Le Roux, Gael [Institute of Environmental Geochemistry, University of Heidelberg, Im Neuenheimer Feld 236 B-69120 Heidelberg (Germany); Fagel, Nathalie [URAP, Departement de Geologie, Universite de Liege, Allee du 6 Aout B18 Sart Tilman B4000 - Liege (Belgium)

    2007-05-15

    Europe has been continuously polluted throughout the last two millennia. During the Roman Empire, these pollutions were mainly from ore extraction and smelting across Europe. Then, during the Middle Ages and the Early times of Industrial revolution (i.e. 1750), these pollutions extended to coal burning and combustion engine. Belgian ombrotrophic peat bogs have proved an effective archive of these pollutants and provide the opportunity to reconstruct the history of atmospheric deposition in NW Europe. The results of recent and past trace metal accumulation and Pb isotopes from a one-meter peat core (in the Misten peat bog) have been derived using XRF and Nu-plasma MC-ICP-MS. Combined with {sup 14}C and {sup 210}Pb dates these data have enabled us to trace fluxes in anthropogenic pollution back to original Roman times. Several periods of well-known Pb pollution events are clearly recorded including the Early and Late Roman Empire, the Middle Ages and the second industrial revolution. Also recorded is the introduction of leaded gasoline, and more recently the introduction of unleaded gasoline. Lead isotopes in this site have also enabled us to fingerprint several regional and global sources of anthropogenic particles.

  2. Atmospheric lead and heavy metal pollution records from a Belgian peat bog spanning the last two millenia. Human impact on a regional to global scale

    Energy Technology Data Exchange (ETDEWEB)

    De Vleeschouwer, Francois; Gerard, Laetitia; Fagel, Nathalie [URAP, Departement de Geologie, Universite de Liege, Allee du 6 Aout B18 Sart Tilman B4000 - Liege (Belgium); Goormaghtigh, Catherine; Mattielli, Nadine [Unite de recherche: ' ' Isotopes, Petrologie et Environnement' ' , Departement des Sciences de la Terre et de l' Environnement, CP 160/02 Universite Libre de Bruxelles, Avenue FD. Roosevelt, 50, B-1050 Bruxelles (Belgium); Le Roux, Gael [Institute of Environmental Geochemistry, University of Heidelberg, Im Neuenheimer Feld 236 B-69120 Heidelberg (Germany)

    2007-05-15

    Europe has been continuously polluted throughout the last two millennia. During the Roman Empire, these pollutions were mainly from ore extraction and smelting across Europe. Then, during the Middle Ages and the Early times of Industrial revolution (i.e. 1750), these pollutions extended to coal burning and combustion engine. Belgian ombrotrophic peat bogs have proved an effective archive of these pollutants and provide the opportunity to reconstruct the history of atmospheric deposition in NW Europe. The results of recent and past trace metal accumulation and Pb isotopes from a one-meter peat core (in the Misten peat bog) have been derived using XRF and Nu-plasma MC-ICP-MS. Combined with {sup 14}C and {sup 210}Pb dates these data have enabled us to trace fluxes in anthropogenic pollution back to original Roman times. Several periods of well-known Pb pollution events are clearly recorded including the Early and Late Roman Empire, the Middle Ages and the second industrial revolution. Also recorded is the introduction of leaded gasoline, and more recently the introduction of unleaded gasoline. Lead isotopes in this site have also enabled us to fingerprint several regional and global sources of anthropogenic particles. (author)

  3. Mineral content in Sphagnum mosses from ombrotrophic bogs of southwestern Poland: pattern in species and elements

    Directory of Open Access Journals (Sweden)

    Bronisław Wojtuń

    2014-01-01

    Full Text Available Major elements (N, P, K, Ca, Mg, Na, Fe were analyzed in 11 Sphagnum species from ombrotrophic bogs in southwestern Poland. The material included species from wet to dry microsites. The highest levels of elements were recorded for S. lindbergii, whereas S. balticum and S. cuspidatum were poorest in elements. The microhabitat gradient from hummock to hollow species is clearly reflected by decreasing concentrations of Ca and Mg, and increasing concentration of Na. Phosphorus, K and N were much more enriched into moss tissues than the remaining elements. These three nutrients were also accumulated in the upper green parts of mosses, while the concentrations of Na and Fe were higher in the bottom brown parts. There were no differences in Ca and Mg between the green and brown segments.

  4. Intercomparison of radiocarbon bomb pulse and {sup 210}Pb age models. A study in a peat bog core from North Poland

    Energy Technology Data Exchange (ETDEWEB)

    Piotrowska, Natalia, E-mail: natalia.piotrowska@polsl.p [Department of Radioisotopes, Institute of Physics, Silesian University of Technology, Krzywoustego, 2, Gliwice 44100 (Poland); Vleeschouwer, Francois De; Sikorski, Jaroslaw; Pawlyta, Jacek [Department of Radioisotopes, Institute of Physics, Silesian University of Technology, Krzywoustego, 2, Gliwice 44100 (Poland); Fagel, Nathalie; Roux, Gael Le [Clays and Palaeoclimate Unit, Department of Geology, University of Liege, Allee du 6 Aout, B18, Sart Tilman, Liege 4000 (Belgium); Pazdur, Anna [Department of Radioisotopes, Institute of Physics, Silesian University of Technology, Krzywoustego, 2, Gliwice 44100 (Poland)

    2010-04-15

    Radiocarbon and {sup 210}Pb were measured on the uppermost 40 cm of a Wardenaar peat core retrieved from a Baltic raised bog at Slowinskie Blota (Pomerania, North Poland). This site is the subject of ongoing multiproxy studies covering the last 1300 years. Radiocarbon age model was constructed on the basis of 14 AMS dates obtained on selected Sphagnum spp. fragments, with use of P{sub S}equence tool. We present here a comparison of this model with the age model obtained using CRS model classically applied to {sup 210}Pb measurements.

  5. History of atmospheric deposition of Cd, Hg, and Pb in North America: Evidence from lake and peat bog sediments

    International Nuclear Information System (INIS)

    Norton, S.A.; Dillon, P.J.; Evans, R.D.; Mierle, G.; Kahl, J.S.

    1990-01-01

    The precipitation chemistry and lake and peat sediment chemistry of three metals emitted to the atmosphere in significant amounts as a result of anthropogenic activity are reviewed. The three metals, Cd, Hg, and Pb, have contrasting source terms, atmospheric residence times, and chemical mobility. Lake and ombrotrophic peat bog sediments record increases in the concentrations and accumulation rates of the metals for most of temperate North America for the last 100 years. These increases are largely related to the burning of coal, smelting of nonferrous metals, the transportation industry, and the industrial production of chlorine. Modern atmospheric fluxes of Cd in central North America are about 1,000 times background fluxes; accumulation rates for Cd in sediments have increased two to 3 times above background, beginning about 100 years ago. Global scale Hg pollution off the atmosphere is suggested by concentrations in northern hemisphere air that are double the Hg content of southern hemisphere air. Accumulation rates of Hg in sediment have approximately doubled in the last 100 years. However, these rates are approximately an order of magnitude less than those for Cd. Modern increases in Pb concentrations are ubiquitous for all lakes examines thus far in North America. Input is from multiple sources and thus the timing of increased accumulation rates in sediment varies across the continent. Typical modern accumulation rates reach maxima at 20 to 30 mg/sq-m/yr, or 100 times that of Cd and 1,000 times that off Hg. Recent decreases in atmospheric lead are reflected in decreases in the accumulation rate of Pb in both lake and peat bog sediment in eastern North America

  6. Polyphenolic Compositions and Chromatic Characteristics of Bog Bilberry Syrup Wines

    Directory of Open Access Journals (Sweden)

    Shu-Xun Liu

    2015-11-01

    Full Text Available Phenolic compounds determine the color quality of fruit wines. In this study, the phenolic compound content and composition, color characteristics and changes during 6 months of bottle aging were studied in wines fermented with bog bilberry syrup under three different pHs. The total anthocyanins and total phenols were around 15.12–16.23 mg/L and 475.82 to 486.50 mg GAE/L in fresh wines and declined 22%–31% and about 11% in bottle aged wines, respectively. In fresh wines, eight anthocyanins, six phenolic aids and 14 flavonols, but no flavon-3-ols were identified; Malvidin-3-O-glucoside, petunidin-3-O-glucoside and delphinium-3-O-glucoside were the predominant pigments; Chlorogentic acid was the most abundant phenolic acid, and quercetin-3-O-galactoside and myricetin-3-O-galactoside accounted for nearly 90% of the total flavonols. During 6 months of bottle storage, the amounts of all the monomeric anthocyanins and phenolic acids were reduced dramatically, while the glycosidyl flavonols remained constant or were less reduced and their corresponding aglycones increased a lot. The effects of aging on blueberry wine color were described as the loss of color intensity with a dramatic change in color hue, from initial red-purple up to final red-brick nuances, while the pH of the fermentation matrix was negatively related to the color stability of aged wine.

  7. Sphagnum-dominated bog systems are highly effective yet variable sources of bio-available iron to marine waters

    International Nuclear Information System (INIS)

    Krachler, Regina; Krachler, Rudolf F.; Wallner, Gabriele; Steier, Peter; El Abiead, Yasin; Wiesinger, Hubert; Jirsa, Franz; Keppler, Bernhard K.

    2016-01-01

    Iron is a micronutrient of particular interest as low levels of iron limit primary production of phytoplankton and carbon fluxes in extended regions of the world's oceans. Sphagnum-peatland runoff is extraordinarily rich in dissolved humic-bound iron. Given that several of the world's largest wetlands are Sphagnum-dominated peatlands, this ecosystem type may serve as one of the major sources of iron to the ocean. Here, we studied five near-coastal creeks in North Scotland using freshwater/seawater mixing experiments of natural creek water and synthetic seawater based on a "5"9Fe radiotracer technique combined with isotopic characterization of dissolved organic carbon by Accelerator Mass Spectrometry. Three of the creeks meander through healthy Sphagnum-dominated peat bogs and the two others through modified peatlands which have been subject to artificial drainage for centuries. The results revealed that, at the time of sampling (August 16–24, 2014), the creeks that run through modified peatlands delivered 11–15 μg iron per liter creek water to seawater, whereas the creeks that run through intact peatlands delivered 350–470 μg iron per liter creek water to seawater. To find out whether this humic-bound iron is bio-available to marine algae, we performed algal growth tests using the unicellular flagellated marine prymnesiophyte Diacronema lutheri and the unicellular marine green alga Chlorella salina, respectively. In both cases, the riverine humic material provided a highly bio-available source of iron to the marine algae. These results add a new item to the list of ecosystem services of Sphagnum-peatlands. - Highlights: • We report that peat-bogs are sources of bio-available iron to marine algae. • This iron is effectively chelated with aquatic humic acids. • The radiocarbon age of the iron-carrying aquatic humic acids was up to 550 years. • Analysis was focused on mixing experiments of iron-rich creek water with seawater. • Drained peatlands with

  8. Sphagnum-dominated bog systems are highly effective yet variable sources of bio-available iron to marine waters

    Energy Technology Data Exchange (ETDEWEB)

    Krachler, Regina, E-mail: regina.krachler@univie.ac.at [Institute of Inorganic Chemistry, University of Vienna, Währingerstraße 42, 1090 Vienna (Austria); Krachler, Rudolf F.; Wallner, Gabriele [Institute of Inorganic Chemistry, University of Vienna, Währingerstraße 42, 1090 Vienna (Austria); Steier, Peter [Isotope Research and Nuclear Physics, University of Vienna, Währingerstraße 17, 1090 Vienna (Austria); El Abiead, Yasin; Wiesinger, Hubert [Institute of Inorganic Chemistry, University of Vienna, Währingerstraße 42, 1090 Vienna (Austria); Jirsa, Franz [Institute of Inorganic Chemistry, University of Vienna, Währingerstraße 42, 1090 Vienna (Austria); University of Johannesburg, Department of Zoology, P. O. Box 524, Auckland Park 2006 (South Africa); Keppler, Bernhard K. [Institute of Inorganic Chemistry, University of Vienna, Währingerstraße 42, 1090 Vienna (Austria)

    2016-06-15

    Iron is a micronutrient of particular interest as low levels of iron limit primary production of phytoplankton and carbon fluxes in extended regions of the world's oceans. Sphagnum-peatland runoff is extraordinarily rich in dissolved humic-bound iron. Given that several of the world's largest wetlands are Sphagnum-dominated peatlands, this ecosystem type may serve as one of the major sources of iron to the ocean. Here, we studied five near-coastal creeks in North Scotland using freshwater/seawater mixing experiments of natural creek water and synthetic seawater based on a {sup 59}Fe radiotracer technique combined with isotopic characterization of dissolved organic carbon by Accelerator Mass Spectrometry. Three of the creeks meander through healthy Sphagnum-dominated peat bogs and the two others through modified peatlands which have been subject to artificial drainage for centuries. The results revealed that, at the time of sampling (August 16–24, 2014), the creeks that run through modified peatlands delivered 11–15 μg iron per liter creek water to seawater, whereas the creeks that run through intact peatlands delivered 350–470 μg iron per liter creek water to seawater. To find out whether this humic-bound iron is bio-available to marine algae, we performed algal growth tests using the unicellular flagellated marine prymnesiophyte Diacronema lutheri and the unicellular marine green alga Chlorella salina, respectively. In both cases, the riverine humic material provided a highly bio-available source of iron to the marine algae. These results add a new item to the list of ecosystem services of Sphagnum-peatlands. - Highlights: • We report that peat-bogs are sources of bio-available iron to marine algae. • This iron is effectively chelated with aquatic humic acids. • The radiocarbon age of the iron-carrying aquatic humic acids was up to 550 years. • Analysis was focused on mixing experiments of iron-rich creek water with seawater. • Drained

  9. Flexibility instead of regulation. Is the Energy Transition bogged down?; Flexibilitaet statt Regulierung. Ist die Energiewende festgefahren?

    Energy Technology Data Exchange (ETDEWEB)

    Gochermann, Josef [Hochschule Osnabrueck, Lingen (Germany). Professur Marketing und Technologiemanagement

    2017-07-15

    The growth in renewable energy systems is stagnating. Is the energy transition bogged down? Is the transition to the new energy world over-regulated? In addition to the regulation of the large systems at the national level, the energy users need more scope and flexibility at regional and on individual level. The present article deals with the most important criticisms regarding the energy transition and provides references on their solution. [German] Der Zuwachs an erneuerbaren Energieanlagen stagniert. Ist die Energiewende festgefahren? Wird der Uebergang in die neue Energiewelt ueberreguliert? Neben der Regulation der grossen Systeme auf nationaler Ebene braucht die Energiewende mehr Freiraum und Flexibilitaet auf regionaler und auf individualer Ebene. Der vorliegende Artikel greift die wichtigsten Kritikpunkte in Bezug auf die Energiewende auf und gibt Hinweise zu deren Loesung.

  10. Turfeiras da Serra do Espinhaço Meridional - MG: I - caracterização e classificação Peat bogs of the Serra do Espinhaço Meridional - Minas Gerais, Brazil: I - characterization and classification

    Directory of Open Access Journals (Sweden)

    Alexandre Christófaro Silva

    2009-10-01

    Full Text Available As turfeiras são ambientes especiais para estudos relacionados com a dinâmica da matéria orgânica, evolução das paisagens, mudanças climáticas e ciclos de poluição atmosférica locais, regionais e globais. Elas contribuem para o sequestro global de carbono, funcionam como reservatórios de água e constituem o ambiente de uma biodiversidade endêmica. A Serra do Espinhaço Meridional (SdEM, "Reserva da Biosfera Terrestre", apresenta uma área significativa formada por diferentes tipos de turfeira, que foram descritas em três perfis, situados a 1.250 m (P1, 1.800 m (P2 e 1.350 m (P4 de altitude e classificados respectivamente como Organossolo Háplico Sáprico térrico (P1, Organossolo Háplico Fíbrico típico (P2 e Organossolo Háplico Hêmico típico (P4, de acordo com o Sistema Brasileiro de Classificação de Solos. Os três perfis foram caracterizados morfologicamente e, nas amostras coletadas, foram realizadas análises químicas, físicas e microbiológicas. Verificou-se que a localização, a altitude e a drenagem influenciaram os atributos morfológicos, físicos, químicos e microbiológicos das turfeiras da SdEM. O estádio de decomposição da matéria orgânica é mais avançado com a melhoria da drenagem nas turfeiras. O teor de metais pesados está relacionado com o teor e a composição granulométrica da fração mineral e com a localização das turfeiras. O perfil P1 apresentou os mais elevados teores médios de Ti, Zr e Pb; em P2 foram detectados os teores médios mais elevados de Mn, Zn e Cu; e o teor médio de Fe é mais elevado em P4. A intensidade da atividade microbiológica das turfeiras P2 e P4 relacionou-se com sua drenagem e com o teor de metais pesados de suas camadas.Peat bogs are a special environment for studies related with the dynamics of organic matter, landscape evolution and climatic changes and with local, regional and global cycles of atmospheric pollution. Peat bogs contribute to the global C

  11. Effects of land use intensity on the full greenhouse gas balance in an Atlantic peat bog

    Directory of Open Access Journals (Sweden)

    S. Beetz

    2013-02-01

    Full Text Available Wetlands can either be net sinks or net sources of greenhouse gases (GHGs, depending on the mean annual water level and other factors like average annual temperature, vegetation development, and land use. Whereas drained and agriculturally used peatlands tend to be carbon dioxide (CO2 and nitrous oxide (N2O sources but methane (CH4 sinks, restored (i.e. rewetted peatlands rather incorporate CO2, tend to be N2O neutral and release CH4. One of the aims of peatland restoration is to decrease their global warming potential (GWP by reducing GHG emissions.

    We estimated the greenhouse gas exchange of a peat bog restoration sequence over a period of 2 yr (1 July 2007–30 June 2009 in an Atlantic raised bog in northwest Germany. We set up three study sites representing different land use intensities: intensive grassland (deeply drained, mineral fertilizer, cattle manure and 4–5 cuts per year; extensive grassland (rewetted, no fertilizer or manure, up to 1 cutting per year; near-natural peat bog (almost no anthropogenic influence. Daily and annual greenhouse gas exchange was estimated based on closed-chamber measurements. CH4 and N2O fluxes were recorded bi-weekly, and net ecosystem exchange (NEE measurements were carried out every 3–4 weeks. Annual sums of CH4 and N2O fluxes were estimated by linear interpolation while NEE was modelled.

    Regarding GWP, the intensive grassland site emitted 564 ± 255 g CO2–C equivalents m−2 yr−1 and 850 ± 238 g CO2–C equivalents m−2 yr−1 in the first (2007/2008 and the second (2008/2009 measuring year, respectively. The GWP of the extensive grassland amounted to −129 ± 231 g CO2–C equivalents m−2 yr−1 and 94 ± 200 g CO2–C equivalents m−2 yr

  12. Diatoms from a peat bog on the Pešter plateau (southwestern Serbia: New records for diatom flora of Serbia

    Directory of Open Access Journals (Sweden)

    Vidaković Danijela

    2016-01-01

    Full Text Available The distribution of diatoms was studied in three types of diatom communities (epiphytes, benthos and plankton of a peat bog on the Pešter plateau. The observed diatom flora inhabited all investigated communities, comprising in total 250 taxa in 53 genera. Among them, 45 taxa were new records for the Serbian diatom flora. Identified taxa belonged to different groups of algae, however alkaliphile diatoms were dominant. New ecological data for Encyonopsis minuta, Pinnularia isostauron and P. marchica are presented here. All the diatoms were documented by light micrographs, and brief notes on their morphology, distribution and ecology are provided. [Projekat Ministarstva nauke Republike Srbije, br. TR 037009

  13. Effect of fire on phosphorus forms in Sphagnum moss and peat soils of ombrotrophic bogs.

    Science.gov (United States)

    Wang, Guoping; Yu, Xiaofei; Bao, Kunshan; Xing, Wei; Gao, Chuanyu; Lin, Qianxin; Lu, Xianguo

    2015-01-01

    The effect of burning Sphagnum moss and peat on phosphorus forms was studied with controlled combustion in the laboratory. Two fire treatments, a light fire (250 °C) and a severe fire (600 °C), were performed in a muffle furnace with 1-h residence time to simulate the effects of different forest fire conditions. The results showed that fire burning Sphagnum moss and peat soils resulted in losses of organic phosphorus (Po), while inorganic phosphorus (Pi) concentrations increased. Burning significantly changed detailed phosphorus composition and availability, with severe fires destroying over 90% of organic phosphorus and increasing the availability of inorganic P by more than twofold. Our study suggest that, while decomposition processes in ombrotrophic bogs occur very slowly, rapid changes in the form and availability of phosphorus in vegetation and litter may occur as the result of forest fires on peat soils. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. Ion exchange in sphagnum and its relation to bog ecology

    Energy Technology Data Exchange (ETDEWEB)

    Clymo, R S

    1963-01-01

    In sphagnum cuspidatum unesterified polyuronic acids form 12 percent of the dry weight; in S. acutifolium 25 percent of the dry weight. A good correlation has been found for sphagna between the content of unesterified polyuronic acid and the cation exchange ability, and between cation exchange ability and height of normal habitat above the water table. Anion exchange ability in sphagna is less than 0.0026 m.eq./g. d.w. compared with about 1.2 m.eq./g. d.w. for cations at pH values above 7. In natural conditions the exchange sites are, however, only partly dissociated. The production of new plant material in a bog dependent on rainwater for nurients can be sufficient to maintain the pH below 4.5, but on other than H/sup +/ could be retained in exchangeable form. A greater proportion of polyvalent cations could be retained. The kinetics of cation exchange are consistent with a heterogeneous exchange phase containing regions of high charge density and regions with lower charge density. At equilibrium the proportions of different cations in the exchange phase are largely explicable by a Donnan distribution, but there are notable exceptions. Two estimates based on donnan distribution suggest that with low external pH and/or low cation concentration the apparent concentration of exchange sites may be 2-3 eq./l., falling with rise in pH and/or increase in cation concentration to 0.9 -1.5 eq./l. The apparent dissociation coefficient also varies in these conditions from 2 x 10/sup -3/ to 1 x 10/sup -4/.

  15. The Effect of Long-term Nutrient Addition on Peat Properties in an Ombrotrophic Bog

    Science.gov (United States)

    Moore, T. R.; Bubier, J. L.; Knorr, K. H.; Roy, C.

    2017-12-01

    Atmospheric inputs of nutrients, particularly N and P, to ecosystems have increased and may have a significant effect on nutrient-deficient peatlands such as bogs. At the Mer Bleue ombrotrophic bog near Ottawa, Canada, we have conducted an experiment over 10 to 20 years by adding 1.6 to 6.4 g N m-2 yr-1 (as NH4NO3), with/without 6 g P m-2 yr-1 (as K phosphate), to evaluate the effect of increased inputs on ecosystem functions. Increased N and P amendment has changed the vegetation from a mixed shrub-Sphagnum community into one dominated by shrubs with the disappearance of mosses, with changes in plant production and litter input. The largest N and P amendments have resulted in an increase in bulk density at 0-10 cm and a lowering of the peat surface by 10 to 20 cm, creating an effective rise in the water table and an increase in CH4 emission from 15 to 50 mg m-2 d-1. Peat cores to a depth of 40 cm were collected after 10 to 15 yr of amendment and showed little change in soil pH (range 4.1 to 4.5). There were substantial increases in the concentration of N and P in the peat (8 to 14 and 0.5 to 1.5 mg g-1, respectively) and general decreases in Ca and Mg concentration. The von Post humification index increased by about 1 unit in the heavily fertilized plots, with shrub leaves replacing Sphagnum as the primary litterfall. FTIR analysis of the 0-20 cm peat showed significant increases in abundance of phenolic+aliphatic, aromatic, and carboxylic relative to polysaccharide components, revealed by the following ratios of absorbance at the respective wavenumbers: 1420/1090 cm-1, 0.41 to 0.45; 1510/1090 cm-1, 0.23 to 0.30; 1630/1090 cm-1, 0.53 to 0.65; and 1720/1090 cm-1, 0.44 to 0.48, respectively. Laboratory incubations of peat samples showed that potential rates of aerobic CH4 consumption were unaffected by nutrient treatment, apart from position relative to the water table, whereas potential rates of anaerobic CH4 production near the water table increased under the P

  16. Treatment of peat bogs harvested by deep digging technique

    International Nuclear Information System (INIS)

    Hoernsten, L.

    1992-06-01

    The aim of this study is to describe how peat bogs harvested by deep digging technique can be treated after harvesting has come to an end. The study points out treatment methods, how the treatments are carried out and to indicate the most appropriate method of harvest for optimum results. Costs and benefits are calculated for the methods involving cultivation. The knowledge gained from traditional peat harvesting technique indicate forestry, energy wood production and establishment of ponds as possible alternatives. Energy grass cultivation and establishments of game parks have not been tested. but are assumed to be viable on suitable sites. Establishment of duck ponds are also possible, even though conditions for these are better on firm ground. In this study spruce is estimated to produce 200 cubic meters during 105 year whilst pine produces 300 cubic meters. Calculations for pine and spruce estimate costs of respectively 17000 and 18000 SEK per hectare after 105 years. Energy wood production is estimated to be 11.6 tons dry matter per hectare and year which gives a net cost of 19000 SEK per hectare. Similarly energy grass cultivation results in an average annual harvest of 6.5 ton dry matter and a cost of 59000 SEK per hectare. If the results are applied to three specific cases, then forest cultivation and establishment of ponds are possible in all cases. Neither energy wood nor energy grass are appropriate in any of the three regions. At the particular site for this study all methods mentioned are possible. Depending on whether draining leads to a high or low water table, the most appropriate course would be the establishment of a pond respectively a game park of forest cultivation. (59 refs., 12 tabs., 4 figs.)

  17. Greenhouse gas exchange of rewetted bog peat extraction sites and a Sphagnum cultivation site in northwest Germany

    Science.gov (United States)

    Beyer, C.; Höper, H.

    2015-04-01

    During the last decades an increasing area of drained peatlands has been rewetted. Especially in Germany, rewetting is the principal treatment on cutover sites when peat extraction is finished. The objectives are bog restoration and the reduction of greenhouse gas (GHG) emissions. The first sites were rewetted in the 1980s. Thus, there is a good opportunity to study long-term effects of rewetting on greenhouse gas exchange, which has not been done so far on temperate cutover peatlands. Moreover, Sphagnum cultivating may become a new way to use cutover peatlands and agriculturally used peatlands as it permits the economical use of bogs under wet conditions. The climate impact of such measures has not been studied yet. We conducted a field study on the exchange of carbon dioxide, methane and nitrous oxide at three rewetted sites with a gradient from dry to wet conditions and at a Sphagnum cultivation site in NW Germany over the course of more than 2 years. Gas fluxes were measured using transparent and opaque closed chambers. The ecosystem respiration (CO2) and the net ecosystem exchange (CO2) were modelled at a high temporal resolution. Measured and modelled values fit very well together. Annually cumulated gas flux rates, net ecosystem carbon balances (NECB) and global warming potential (GWP) balances were determined. The annual net ecosystem exchange (CO2) varied strongly at the rewetted sites (from -201.7 ± 126.8 to 29.7± 112.7g CO2-C m-2 a-1) due to differing weather conditions, water levels and vegetation. The Sphagnum cultivation site was a sink of CO2 (-118.8 ± 48.1 and -78.6 ± 39.8 g CO2-C m-2 a-1). The annual CH4 balances ranged between 16.2 ± 2.2 and 24.2 ± 5.0g CH4-C m-2 a-1 at two inundated sites, while one rewetted site with a comparatively low water level and the Sphagnum farming site show CH4 fluxes close to 0. The net N2O fluxes were low and not significantly different between the four sites. The annual NECB was between -185.5 ± 126.9 and 49

  18. Greenhouse gas emissions from rewetted bog peat extraction sites and a Sphagnum cultivation site in Northwest Germany

    Science.gov (United States)

    Beyer, C.; Höper, H.

    2014-03-01

    During the last three decades, an increasing area of drained peatlands was rewetted. This was done with the objective to convert these sites from sources back to sinks or, at least, to much smaller sources of greenhouse gases (GHG). However, available data is still scarce, especially on the long-term climatic effects of rewetting of temperate bogs. Moreover, first field trials are established for Sphagnum cultivating (paludiculture) on wet bog sites and an assessment of the climate impact of such measures has not been studied yet. We conducted a field study on the exchange of carbon dioxide, methane and nitrous oxide at three rewetted sites with a gradient from dry to wet conditions and at a Sphagnum cultivation site in NW Germany over more than two years. Gas fluxes were measured using transparent and opaque closed chambers. The ecosystem respiration (CO2) and the net ecosystem exchange (CO2) were modelled in high time resolution using automatically monitored climate data. Measured and modelled values fit very well together (R2 between 0.88 and 0.98). Annually cumulated gas flux rates, net ecosystem carbon balances (NECB) and global warming potential (GWP) balances were determined. The annual net ecosystem exchange (CO2) varied strongly at the rewetted sites (from -201.7 ± 126.8 to 29.7 ± 112.7 g CO2-C m-2 a-1) due to different weather conditions, water level and vegetation. The Sphagnum cultivation site was a sink of CO2 (-118.8 ± 48.1 and -78.6 ± 39.8 g CO2-C m-2 a-1). The yearly CH4 balances ranged between 16.2 ± 2.2 and 24.2 ± 5.0 g CH4-C m-2 a-1 at two inundated sites, while one rewetted site with a comparatively low water level and the Sphagnum farming site show CH4 fluxes close to zero. The net N2O fluxes were low and not significantly different between the four sites. The annual NECB at the rewetted sites was between -183.8 ± 126.9 and 51.6 ± 112.8 g CO2-C m-2 a-1 and at the Sphagnum cultivating site -114.1 ± 48.1 and -75.3 ± 39.8 g CO2-C m-2 a-1

  19. The Sphagnum microbiome supports bog ecosystem functioning under extreme conditions.

    Science.gov (United States)

    Bragina, Anastasia; Oberauner-Wappis, Lisa; Zachow, Christin; Halwachs, Bettina; Thallinger, Gerhard G; Müller, Henry; Berg, Gabriele

    2014-09-01

    Sphagnum-dominated bogs represent a unique yet widely distributed type of terrestrial ecosystem and strongly contribute to global biosphere functioning. Sphagnum is colonized by highly diverse microbial communities, but less is known about their function. We identified a high functional diversity within the Sphagnum microbiome applying an Illumina-based metagenomic approach followed by de novo assembly and MG-RAST annotation. An interenvironmental comparison revealed that the Sphagnum microbiome harbours specific genetic features that distinguish it significantly from microbiomes of higher plants and peat soils. The differential traits especially support ecosystem functioning by a symbiotic lifestyle under poikilohydric and ombrotrophic conditions. To realise a plasticity-stability balance, we found abundant subsystems responsible to cope with oxidative and drought stresses, to exchange (mobile) genetic elements, and genes that encode for resistance to detrimental environmental factors, repair and self-controlling mechanisms. Multiple microbe-microbe and plant-microbe interactions were also found to play a crucial role as indicated by diverse genes necessary for biofilm formation, interaction via quorum sensing and nutrient exchange. A high proportion of genes involved in nitrogen cycle and recycling of organic material supported the role of bacteria for nutrient supply. 16S rDNA analysis indicated a higher structural diversity than that which had been previously detected using PCR-dependent techniques. Altogether, the diverse Sphagnum microbiome has the ability to support the life of the host plant and the entire ecosystem under changing environmental conditions. Beyond this, the moss microbiome presents a promising bio-resource for environmental biotechnology - with respect to novel enzymes or stress-protecting bacteria. © 2014 John Wiley & Sons Ltd.

  20. Understanding the mechanics of processes of recolonization of vegetation in mined peat bogs; Comprendre la mecanique du processus de recolonisation vegetale des tourbieres exploitees

    Energy Technology Data Exchange (ETDEWEB)

    Campbell, D. [Laval University, Quebec, QC (Canada). Department of Biology

    2002-07-01

    The recolonization process in abandoned milled peat bogs was studied to determine why the recolonization of such sites is difficult. The process was considered as a series of environmental filters where only those species with suitable ecological characteristics survive. Several species of mosses, ericaceous shrubs, and trees were studied. The stability of milled peat surfaces was examined with regard to wind erosion potential as a function of decomposition, surface roughness of milled peats, and milled peat substrate stability in a second field study. The germination of and establishment potential of vascular plants was examined in a third study.

  1. Seasonal climate manipulations have only minor effects on litter decomposition rates and N dynamics but strong effects on litter P dynamics of sub-arctic bog species.

    Science.gov (United States)

    Aerts, R; Callaghan, T V; Dorrepaal, E; van Logtestijn, R S P; Cornelissen, J H C

    2012-11-01

    Litter decomposition and nutrient mineralization in high-latitude peatlands are constrained by low temperatures. So far, little is known about the effects of seasonal components of climate change (higher spring and summer temperatures, more snow which leads to higher winter soil temperatures) on these processes. In a 4-year field experiment, we manipulated these seasonal components in a sub-arctic bog and studied the effects on the decomposition and N and P dynamics of leaf litter of Calamagrostis lapponica, Betula nana, and Rubus chamaemorus, incubated both in a common ambient environment and in the treatment plots. Mass loss in the controls increased in the order Calamagrostis Litter chemistry showed within each incubation environment only a few and species-specific responses. Compared to the interspecific differences, they resulted in only moderate climate treatment effects on mass loss and these differed among seasons and species. Neither N nor P mineralization in the litter were affected by the incubation environment. Remarkably, for all species, no net N mineralization had occurred in any of the treatments during 4 years. Species differed in P-release patterns, and summer warming strongly stimulated P release for all species. Thus, moderate changes in summer temperatures and/or winter snow addition have limited effects on litter decomposition rates and N dynamics, but summer warming does stimulate litter P release. As a result, N-limitation of plant growth in this sub-arctic bog may be sustained or even further promoted.

  2. Climate change and water table fluctuation: Implications for raised bog surface variability

    Science.gov (United States)

    Taminskas, Julius; Linkevičienė, Rita; Šimanauskienė, Rasa; Jukna, Laurynas; Kibirkštis, Gintautas; Tamkevičiūtė, Marija

    2018-03-01

    Cyclic peatland surface variability is influenced by hydrological conditions that highly depend on climate and/or anthropogenic activities. A low water level leads to a decrease of peatland surface and an increase of C emissions into the atmosphere, whereas a high water level leads to an increase of peatland surface and carbon sequestration in peatlands. The main aim of this article is to evaluate the influence of hydrometeorological conditions toward the peatland surface and its feedback toward the water regime. A regional survey of the raised bog water table fluctuation and surface variability was made in one of the largest peatlands in Lithuania. Two appropriate indicators for different peatland surface variability periods (increase and decrease) were detected. The first one is an 200 mm y- 1 average net rainfall over a three-year range. The second one is an average annual water depth of 25-30 cm. The application of these indicators enabled the reconstruction of Čepkeliai peatland surface variability during a 100 year period. Processes of peatland surface variability differ in time and in separate parts of peatland. Therefore, internal subbasins in peatland are formed. Subbasins involve autogenic processes that can later affect their internal hydrology, nutrient status, and vegetation succession. Internal hydrological conditions, surface fluctuation, and vegetation succession in peatland subbasins should be taken into account during evaluation of their state, nature management projects, and other peatland research works.

  3. Why are there few gas bubbles in deep peat in British raised and blanket peat bogs?

    Directory of Open Access Journals (Sweden)

    R.S. Clymo

    2015-08-01

    Full Text Available (1 There is evidence of gas-filled voids - ‘bubbles’ - in deep (> 50–100 cm peat in North America. (2 I used corers, designed to collect samples of accurately known volume, to sample peat profiles down to maximum depth 700 cm at five varied bog sites in northern England and southern Scotland, and measured the proportion of space apparently occupied by bubbles. (3 Of 126 samples in peat below 50 cm depth, three had bubbles occupying 12–15 % of the volume (and one of these was at only 55 cm depth. The other 123 had apparent bubbles distributed in Gaussian fashion, positively and negatively, about zero proportion of total volume and with standard deviation less than 2 %, consistent with these ‘bubbles’ being measurement error. (4 In northern England and southern Scotland, compared with North America, less variable temperature and cooler summers may lead to concentrations of dissolved gas that are generally too low to allow bubbles to form. Even where bubbles do form in summer, they may re-dissolve at winter temperatures.

  4. Ecosystem Phenology from Eddy-covariance Measurements: Spring Photosynthesis in a Cool Temperate Bog

    Science.gov (United States)

    Lafleur, P.; Moore, T. R.; Poon, D.; Seaquist, J.

    2005-12-01

    The onset and increase of spring photosynthetic flux of carbon dioxide is an important attribute of the carbon budget of northern ecosystems and we used eddy-covariance measurements from March to May over 5 years at the Mer Bleue ombrotrophic bog to establish the important controls. The onset of ecosystem photosynthesis (day-of-year from 86 to 101) was associated with the disappearance on the snow cover and there is evidence that photosynthesis can continue after a thin new snowfall. The growth of photosynthesis during the spring period was partially associated with light (daily photosynthetically active radiation) but primarily with temperature, with the strongest correlation being observed with peat temperature at a depth of 5 and 10 cm, except in one year in which there was a long snow cover. The vegetation comprises mosses, which are able to photosynthesize very early, evergreen shrubs, which appear dependent on soil warming, and deciduous shrubs, which leaf-out only in late spring. We observed changes in shrub leaf colour from brown to green and concomitant increases in foliar nitrogen and chlorophyll concentrations during the spring in this "evergreen" system. We analyzed MODIS images for periods of overlap of tower and satellite data and found a generally strong correlation, though the infrequent satellite measurements were unable to pick out the onset and timing of rapid growth of photosynthesis in this ecosystem.

  5. Natural bog pine ecosystem in southern Germany is a steady and robust sink of CO2 but a minor source of CH4

    Science.gov (United States)

    Hommeltenberg, Janina; Schmid, Hans Peter; Droesler, Matthias; Werle, Peter

    2013-04-01

    Natural peatland ecosystems sequester carbon dioxide. They do this slowly but steadily, but also emit methane in small rates. Thus peatlands have both positive and negative greenhouse gas balance impacts on the climate system due to their influence on atmospheric CO2 and CH4 concentration. We present data of net ecosystem CO2 exchange (NEE) of almost three years (July 2010 to March 2013) and of methane fluxes over a period of nine months (July 2012 to March 2013), measured by eddy covariance technique in the bog forest "Schechenfilz". The site (47°48' N; 11°19' E, 590 m a.s.l.) is an ICOS-ecosystems associate site, located in the pre-alpine region of southern Germany, where a natural Pinus mugo rotundata forest grows on an undisturbed, almost 6 m thick peat layer. The slow growing bog pines and their low rates of carbon sequestration, in combination with high water table and thus low availability of oxygen, lead to low carbon dioxide fluxes. Photosynthesis as well as soil respiration are considerably attenuated compared to upland sites. Additionally, the high soil water content is damping the impact of dry and hot periods on CO2 exchange. Thus the CO2 balance is very robust to changing environmental parameters. While the CO2 exchange is clearly related to soil temperature and photosynthetic active radiation, we have not yet identified a parameter that governs variations in methane exchange. Various environmental parameters appear to be related to methane emissions (including soil moisture, soil and air temperature and wind direction), but the scatter with respect to half hourly methane fluxes is too large to be useful for gap modeling. Analysis of daily averages reduces the scatter, but since methane exchange exhibits considerable daily variation, daily averages are not useful to fill data gaps of half hourly fluxes. In consequence, as the daily course is the summary result of all environmental parameters having influence on the methane exchange at the half

  6. Grass species influence on plant N uptake - Determination of atmospheric N deposition to a semi-natural peat bog site using a 15N labelling approach

    Science.gov (United States)

    Hurkuck, Miriam; Brümmer, Christian; Spott, Oliver; Flessa, Heinz; Kutsch, Werner L.

    2014-05-01

    Large areas of natural peat bogs in Northwestern Germany have been converted to arable land and were subjected to draining and peat cutting in the past. The few protected peatland areas remaining are affected by high nitrogen (N) deposition. Our study site - a moderately drained raised bog - is surrounded by highly fertilized agricultural land and livestock production. In this study, we used a 15N pool dilution technique called 'Integrated Total Nitrogen Input' (ITNI) to quantify annual deposition of atmospheric N into biomonitoring pots over a two-year period. Since it considers direct N uptake by plants, it was expected to result in higher N input than conventional methods for determination of N deposition (e.g. micrometeorological approaches, bulk N samplers). Using Lolium multiflorum and Eriophorum vaginatum as monitor plants and low, medium and high levels of fertilization, we aimed to simulate increasing N deposition to planted pots and to allocate airborne N after its uptake by the soil-plant system in aboveground biomass, roots and soil. Increasing N fertilization was positively correlated with biomass production of Eriophorum vaginatum, whereas atmospheric plant N uptake decreased and highest airborne N input of 899.8 ± 67.4 µg N d-1 pot-1 was found for low N fertilization. In contrast, Lolium multiflorum showed a clear dependency of N supply on plant N uptake and was highest (688.7 ± 41.4 µg N d-1 pot-1) for highly fertilized vegetation pots. Our results suggest that grass species respond differently to increasing N input. While crop grasses such as Lolium multiflorum take up N according to N availability, species adopted to nutrient-limited conditions like Eriophorum vaginatum show N saturation effects with increasing N supply. Total airborne N input ranged from about 24 to 66 kg N ha-1 yr-1 dependent on the used indicator plant and the amount of added fertilizer. Parallel determination of atmospheric N deposition using a micrometeorological approach

  7. Geochemical Prospecting of a Uraniferous Bog Deposit at Masugnsbyn, Northern Sweden

    Energy Technology Data Exchange (ETDEWEB)

    Armands, Goesta

    1961-01-15

    In connection with prospecting for uranium ores in northern Sweden a peat bog, situated 4.5 km NW of Masugnsbyn, Norrbotten, Sweden and showing a remarkable content of uranium, was discovered. Closer investigation of several samples of the peat indicated that the comparatively high content of uranium and radon was connected with the occurrence of radioactive springs in the region. It was found that four different kinds of water were responsible for the supply of radioactive material to the peat, viz: ground water, surface water, spring water and ground water emanating from fractured rock. The spring water - probably a mixture of ground water and water from the fractured rock - contains uranium to the extent of micrograms per litre. The pH is about 7. The uranium content of the water system deriving from the fractured rock is about 200-300 micrograms per litre. The maximum radon content is about 3000 emans. The pH is >7 and the specific conductivity about 150 x 10{sup -6}/Ohm/cm The radioactive peat is characterised by extremely low gamma radioactivity which may be due to the recent emplacement of uranium by spring waters. It is suggested that the peat in question has served as a 'collector' for uranium, rare earth metals etc., since the pH condition - pH about 7 - was favourable to the settling of these elements. The uranium enrichment seems to be due to a transport of Na, Mg and Ca bicarbonates emanating from dolomite deposits or pegmatitic granite dikes in the vicinity of the peat, the bicarbonate waters serving as carriers of the uranium.

  8. Videographic Analysis of Eriophorum Vaginatum Spatial Coverage in an Ombotrophic Bog

    Directory of Open Access Journals (Sweden)

    Margaret Kalacska

    2013-12-01

    Full Text Available The use of Remotely Piloted Aircraft Systems (RPAS as well as newer automated unmanned aerial vehicles is becoming a standard method in remote sensing studies requiring high spatial resolution (<1 m and very precise temporal data to capture phenological events. In this study we use a low cost rotorcraft to map Eriophorum vaginatum at Mer Bleue, an ombrotrophic bog located east of Ottawa, ON, Canada. We focus on E. vaginatum because this sedge plays an important role in methane (CH4 gas exchange in peatlands. Using the remote controlled rotorcraft we were able to record, process, and mosaic 11.1 hectares of 4.5 cm spatial resolution imagery extracted from individual frames of video recordings (post georegistration RMSE 4.90 ± 4.95 cm. Our results, based on a supervised classification (96% accuracy of the red, green, blue image planes, indicate a total tussock cover of 2,417 m2. Because the basal area of the plant is more relevant for calculating its contribution to the CH4 flux, the tussock area was related to the basal area from field data (R2 = 0.88, p < 0.0001. Our final results indicate a total basal area of 1,786 ± 62.8 m2. Based on temporal measurements of CH4 flux from the peatland as a whole that vary over the growing season, we estimate the E. vaginatum contribution to range from 3.0% to 17.3% of that total. Overall, our low cost approach was an effective non-destructive way to derive E. vaginatum coverage and estimate CH4 exchange over the growing season.

  9. Geochemical Prospecting of a Uraniferous Bog Deposit at Masugnsbyn, Northern Sweden

    International Nuclear Information System (INIS)

    Armands, Goesta

    1961-01-01

    In connection with prospecting for uranium ores in northern Sweden a peat bog, situated 4.5 km NW of Masugnsbyn, Norrbotten, Sweden and showing a remarkable content of uranium, was discovered. Closer investigation of several samples of the peat indicated that the comparatively high content of uranium and radon was connected with the occurrence of radioactive springs in the region. It was found that four different kinds of water were responsible for the supply of radioactive material to the peat, viz: ground water, surface water, spring water and ground water emanating from fractured rock. The spring water - probably a mixture of ground water and water from the fractured rock - contains uranium to the extent of micrograms per litre. The pH is about 7. The uranium content of the water system deriving from the fractured rock is about 200-300 micrograms per litre. The maximum radon content is about 3000 emans. The pH is >7 and the specific conductivity about 150 x 10 -6 /Ohm/cm The radioactive peat is characterised by extremely low gamma radioactivity which may be due to the recent emplacement of uranium by spring waters. It is suggested that the peat in question has served as a 'collector' for uranium, rare earth metals etc., since the pH condition - pH about 7 - was favourable to the settling of these elements. The uranium enrichment seems to be due to a transport of Na, Mg and Ca bicarbonates emanating from dolomite deposits or pegmatitic granite dikes in the vicinity of the peat, the bicarbonate waters serving as carriers of the uranium

  10. Recent atmospheric lead deposition recorded in an ombrotrophic peat bog of Great Hinggan Mountains, Northeast China, from 210Pb and 137Cs dating

    International Nuclear Information System (INIS)

    Bao, K.; Xia, W.; Lu, X.; Wang, G.

    2010-01-01

    Radioactive markers are useful in dating lead deposition patterns from industrialization in peat archive. Peat cores were collected in an ombrotrophic peat bog in the Great Hinggan Mountains in Northeast China in September 2008 and dated using 210 Pb and 137 Cs radiometric techniques. The mosses in both cores were examined systematically for dry bulk density, water and ash content. Lead also was measured using atomic emission spectroscopy with inductively coupled plasma (ICP-AES). Both patterned peat profiles were preserved well without evident anthropogenic disturbance. Unsupported 210 Pb and 137 Cs decreased with the depth in both of the two sample cores. The 210 Pb chronologies were established using the constant rate of supply model (CRS) and are in good agreement with the 137 Cs time marker. Recent atmospheric 210 Pb flux in Great Hinggan Mountains peat bog was estimated to be 337 Bq m -2 y -1 , which is consistent with published data for the region. Lead deposition rate in this region was also derived from these two peat cores and ranged from 24.6 to 55.8 mg m -2 y -1 with a range of Pb concentration of 14-262 μg g -1 . The Pb deposition patterns were consistent with increasing industrialization over the last 135-170 y, with a peak of production and coal burning in the last 50 y in Northeast China. This work presents a first estimation of atmospheric Pb deposition rate in peatlands in China and suggests an increasing trend of environmental pollution due to anthropogenic contaminants in the atmosphere. More attention should be paid to current local pollution problems, and society should take actions to seek a balance between economic development and environmental protection.

  11. Comparative ecosystem-atmosphere exchange of energy and mass in a European Russian and a central Siberian bog II. Interseasonal and interannual variability of CO2 fluxes

    International Nuclear Information System (INIS)

    Arneth, A.; Kolle, O.; Lloyd, J.; Schulze, E.D.; Kurbatova, J.; Vygodskaya, N.N.

    2002-01-01

    Net ecosystem-atmosphere exchange of CO 2 (NEE) was measured in two boreal bogs during the snow-free periods of 1998, 1999 and 2000. The two sites were located in European Russia (Fyodorovskoye), and in central Siberia (Zotino). Climate at both sites was generally continental but with more extreme summer-winter gradients in temperature at the more eastern site Zotino. The snow-free period in Fyodorovskoye exceeded the snow-free period at Zotino by several weeks. Marked seasonal and interannual differences in NEE were observed at both locations, with contrasting rates and patterns. Amongst the most important contrasts were: (1) Ecosystem respiration at a reference soil temperature was higher at Fyodorovskoye than at Zotino. (2) The diurnal amplitude of summer NEE was larger at Fyodorovskoye than at Zotino. (3) There was a modest tendency for maximum 24 h NEE during average rainfall years to be more negative at Zotino (-0.17 versus -0.15 mol/m 2 /d), suggesting a higher productivity during the summer months. (4) Cumulative net uptake of CO 2 during the snow-free period was strongly related to climatic differences between years. In Zotino the interannual variability in climate, and also in the CO 2 balance during the snow-free period, was small. However, at Fyodorovskoye the bog was a significant carbon sink in one season and a substantial source for CO 2 -C in the next, which was below-average dry. Total snow-free uptake and annual estimates of net CO 2 -C uptake are discussed, including associated uncertainties

  12. Dust is the dominant source of "heavy metals" to peat moss (Sphagnum fuscum) in the bogs of the Athabasca Bituminous Sands region of northern Alberta.

    Science.gov (United States)

    Shotyk, William; Bicalho, Beatriz; Cuss, Chad W; Duke, M John M; Noernberg, Tommy; Pelletier, Rick; Steinnes, Eiliv; Zaccone, Claudio

    2016-01-01

    Sphagnum fuscum was collected from twenty-five ombrotrophic (rain-fed) peat bogs surrounding open pit mines and upgrading facilities of Athabasca Bituminous Sands (ABS) in northern Alberta (AB) in order to assess the extent of atmospheric contamination by trace elements. As a control, this moss species was also collected at a bog near Utikuma (UTK) in an undeveloped part of AB and 264km SW of the ABS region. For comparison, this moss was also collected in central AB, in the vicinity of the City of Edmonton which is approximately 500km to the south of the ABS region, from the Wagner Wetland which is 22km W of the City, from Seba Beach (ca. 90km W) and from Elk Island National Park (ca. 45km E). All of the moss samples were digested and trace elements concentrations determined using ICP-SMS at a commercial laboratory, with selected samples also analyzed using instrumental neutron activation analysis at the University of Alberta. The mosses from the ABS region yielded lower concentrations of Ag, As, Bi, Cd, Cu, Pb, Sb, Tl, and Zn compared to the moss from the Edmonton area. Concentrations of Ni and Mo in the mosses were comparable in these two regions, but V was more abundant in the ABS samples. Compared with the surface vegetation of eight peat cores collected in recent years from British Columbia, Ontario, Quebec and New Brunswick, the mean concentrations of Ag, As, Bi, Cd, Cu, Mo, Ni, Pb, Sb, Tl and Zn in the mosses from the ABS region are generally much lower. In fact, the concentrations of these trace elements in the samples from the ABS region are comparable to the corresponding values in forest moss from remote regions of central and northern Norway. Lithophile element concentrations (Ba, Be, Ga, Ge, Li, Sc, Th, Ti, Zr) explain most of the variation in trace metal concentrations in the moss samples. The mean concentrations of Th and Zr are greatest in the moss samples from the ABS region, reflecting dust inputs to the bogs from open pit mines, aggregate

  13. Small spatial variability in methane emission measured from a wet patterned boreal bog

    Directory of Open Access Journals (Sweden)

    A. Korrensalo

    2018-03-01

    Full Text Available We measured methane fluxes of a patterned bog situated in Siikaneva in southern Finland from six different plant community types in three growing seasons (2012–2014 using the static chamber method with chamber exposure of 35 min. A mixed-effects model was applied to quantify the effect of the controlling factors on the methane flux. The plant community types differed from each other in their water level, species composition, total leaf area (LAITOT and leaf area of aerenchymatous plant species (LAIAER. Methane emissions ranged from −309 to 1254 mg m−2 d−1. Although methane fluxes increased with increasing peat temperature, LAITOT and LAIAER, they had no correlation with water table or with plant community type. The only exception was higher fluxes from hummocks and high lawns than from high hummocks and bare peat surfaces in 2013 and from bare peat surfaces than from high hummocks in 2014. Chamber fluxes upscaled to ecosystem level for the peak season were of the same magnitude as the fluxes measured with the eddy covariance (EC technique. In 2012 and in August 2014 there was a good agreement between the two methods; in 2013 and in July 2014, the chamber fluxes were higher than the EC fluxes. Net fluxes to soil, indicating higher methane oxidation than production, were detected every year and in all community types. Our results underline the importance of both LAIAER and LAITOT in controlling methane fluxes and indicate the need for automatized chambers to reliably capture localized events to support the more robust EC method.

  14. Small spatial variability in methane emission measured from a wet patterned boreal bog

    Science.gov (United States)

    Korrensalo, Aino; Männistö, Elisa; Alekseychik, Pavel; Mammarella, Ivan; Rinne, Janne; Vesala, Timo; Tuittila, Eeva-Stiina

    2018-03-01

    We measured methane fluxes of a patterned bog situated in Siikaneva in southern Finland from six different plant community types in three growing seasons (2012-2014) using the static chamber method with chamber exposure of 35 min. A mixed-effects model was applied to quantify the effect of the controlling factors on the methane flux. The plant community types differed from each other in their water level, species composition, total leaf area (LAITOT) and leaf area of aerenchymatous plant species (LAIAER). Methane emissions ranged from -309 to 1254 mg m-2 d-1. Although methane fluxes increased with increasing peat temperature, LAITOT and LAIAER, they had no correlation with water table or with plant community type. The only exception was higher fluxes from hummocks and high lawns than from high hummocks and bare peat surfaces in 2013 and from bare peat surfaces than from high hummocks in 2014. Chamber fluxes upscaled to ecosystem level for the peak season were of the same magnitude as the fluxes measured with the eddy covariance (EC) technique. In 2012 and in August 2014 there was a good agreement between the two methods; in 2013 and in July 2014, the chamber fluxes were higher than the EC fluxes. Net fluxes to soil, indicating higher methane oxidation than production, were detected every year and in all community types. Our results underline the importance of both LAIAER and LAITOT in controlling methane fluxes and indicate the need for automatized chambers to reliably capture localized events to support the more robust EC method.

  15. Characterizing Early Succession Following Wildfires at Different Severities in Boreal Bog and Fen Peatlands

    Science.gov (United States)

    Ernst, E. J.; Bourgeau-Chavez, L. L.; Kane, E. S.; Wagenbrenner, J. W.; Endres, S.

    2016-12-01

    The Arctic-boreal region is experiencing changes in climate, trending toward warmer summers, resulting in a greater occurrence of wildfires with longer burning periods and higher intensities. Drought-like conditions have dried surface fuels, leading to a higher probability of ignition, even in lowland peatlands. Previous work has been done to characterize post-fire succession rates in Arctic-boreal upland sites, but much less is known of fire effects and early successional dynamics in lowlands. Wildland fires are the number one disturbance in Canada's Northwest Territories (NWT), which characteristically burn at high intensities with large flame fronts, and result in some of the biggest wildfires in the world. Areas surrounding the Great Slave Lake, NWT—including parts of the Taiga Plains, Taiga Shield, and Boreal Plains ecozones—experienced exceptional wildfire activity in 2014 and 2015. We characterized burn severity of the bog and fen peat surface and canopy layers at several burned sites. To determine if the severe ground or crown wildfires were stand-replacing events, we characterized post-fire vegetation in peatlands in 2015 and 2016 based on seedling regeneration. We stratified sites according to estimated water residence times across the three ecozones and made comparisons between data collected at the same sites across years. This work adds much needed context for post-fire succession in boreal peatland ecosystems, as the susceptibility of these systems to burning will continue to increase with a warming climate.

  16. The effects of adding different forms of nitrogen for 14 years on the vegetation composition at Whim Bog

    Science.gov (United States)

    van Dijk, Netty; Levy, Peter; Sheppard, Lucy; Leith, Ian; Leeson, Sarah; Jones, Matt; Dise, Nancy; Sutton, Mark

    2017-04-01

    The effects of adding different forms of nitrogen for 14 years on the vegetation composition at Whim Bog Netty van Dijk, Peter Levy, Lucy Sheppard, Ian Leith, Sarah Leeson, Matt Jones, Nancy Dise, Mark Sutton Centre for Ecology & Hydrology, Bush Estate, Penicuik, UK Reactive nitrogen (Nr) is a major plant nutrient which historically was in short supply in most semi-natural ecosystems. However, as a consequence of an increased use of N fertilisers and more intensive farming methods, atmospheric Nr -deposition and atmospheric ammonia (NH3) concentrations have increased dramatically during the last century. This has a significant effect on semi-natural systems, with some sensitive species disappearing altogether in the vicinity of elevated atmospheric N input. Whether one form of nitrogen has more effect on vegetation changes than the other is less well studied. To get more evidence for this, a field experiment at an ombrotrophic bog, Whim (Scottish Borders). This globally unique experiment was set up in 2002 where different forms and doses of N have been applied systematically. Nitrogen was applied as ammonia (NH3) gas to investigate effects of dry deposition and atmospheric concentrations along a gradient away from a free-air released fumigation line source. Wet deposition is added in the form of NH4Cl and NaNO3, respectively, using a rainwater collection and spraying system, at concentrations ranging from 8 to 56 kg N ha-1 yr-1. Both systems are automated and coupled to meteorological conditions. Within the first three years, the vegetation composition in the dry deposition system changed dramatically with an almost complete loss of Calluna vulgaris, Sphagnum capillifolium and Cladonia Portentosa close to the fumigation line. Further away from the fumigation line the changes were smaller and slower to materialise. In later years the changes in vegetation composition were slowing down. Now, after 14 years of ammonia application, we are analysing the data along the

  17. Carbon dioxide flux and net primary production of a boreal treed bog: Responses to warming and water-table-lowering simulations of climate change

    Science.gov (United States)

    Munir, T. M.; Perkins, M.; Kaing, E.; Strack, M.

    2015-02-01

    Midlatitude treed bogs represent significant carbon (C) stocks and are highly sensitive to global climate change. In a dry continental treed bog, we compared three sites: control, recent (1-3 years; experimental) and older drained (10-13 years), with water levels at 38, 74 and 120 cm below the surface, respectively. At each site we measured carbon dioxide (CO2) fluxes and estimated tree root respiration (Rr; across hummock-hollow microtopography of the forest floor) and net primary production (NPP) of trees during the growing seasons (May to October) of 2011-2013. The CO2-C balance was calculated by adding the net CO2 exchange of the forest floor (NEff-Rr) to the NPP of the trees. From cooler and wetter 2011 to the driest and the warmest 2013, the control site was a CO2-C sink of 92, 70 and 76 g m-2, the experimental site was a CO2-C source of 14, 57 and 135 g m-2, and the drained site was a progressively smaller source of 26, 23 and 13 g CO2-C m-2. The short-term drainage at the experimental site resulted in small changes in vegetation coverage and large net CO2 emissions at the microforms. In contrast, the longer-term drainage and deeper water level at the drained site resulted in the replacement of mosses with vascular plants (shrubs) on the hummocks and lichen in the hollows leading to the highest CO2 uptake at the drained hummocks and significant losses in the hollows. The tree NPP (including above- and below-ground growth and litter fall) in 2011 and 2012 was significantly higher at the drained site (92 and 83 g C m-2) than at the experimental (58 and 55 g C m-2) and control (52 and 46 g C m-2) sites. We also quantified the impact of climatic warming at all water table treatments by equipping additional plots with open-top chambers (OTCs) that caused a passive warming on average of ~ 1 °C and differential air warming of ~ 6 °C at midday full sun over the study years. Warming significantly enhanced shrub growth and the CO2 sink function of the drained

  18. Turfeiras da Serra do Espinhaço Meridional - MG: II - influência da drenagem na composição elementar e substâncias húmicas Peat bogs in the Serra do Espinhaço Meridional - Minas Gerais, Brazil: II - influence of drainage on elemental humus composition and substances

    Directory of Open Access Journals (Sweden)

    Alexandre Christófaro Silva

    2009-10-01

    Full Text Available As turfeiras são Organossolos que resultam de condições ecológicas ideais ao acúmulo de material orgânico, controladas pelos sistemas geomorfológicos e processos geológicos e climáticos globais. Sua constituição física, química e biológica é pouco conhecida. No presente trabalho foi realizado um estudo sobre as turfeiras da Serra do Espinhaço Meridional (SdEM - MG, por meio da descrição e coleta de amostras em três perfis situados a 1.250 m (P1, 1.350 m (P4 e 1.800 m (P2 de altitude. Os três perfis foram caracterizados morfologicamente e, nas amostras coletadas, foram realizadas análises químicas e fracionamento da matéria orgânica em ácidos húmicos, ácidos fúlvicos e humina. A matéria orgânica dos perfis de Turfeiras da SdEM apresentou marcantes diferenças entre si em relação à sua composição química e ao teor das substâncias húmicas e à composição química dos ácidos húmicos. A variação das condições de drenagem foi preponderante para a diferenciação qualitativa e quantitativa da matéria orgânica. A turfeira P1, com moderadas condições de drenagem, apresentou matéria orgânica com maiores relações C/N e O/C, predomínio de ácidos fúlvicos entre as substâncias húmicas e ácidos húmicos e elevada relação C/N. Nas turfeiras P2 e P4, com muito más condições de drenagem, as relações C/N e O/C da matéria orgânica foram mais baixas, a humina predominou amplamente entre as substâncias húmicas e os ácidos húmicos apresentaram a mais baixa relação C/N.Peat bogs are Organosols formed under ideal ecological conditions in terms of the accumulation of organic material, controlled by geomorphological and geological processes and climate. The physical, chemistry and biological constitution of peat bogs is largely unknown. In this study the peat bogs of the Southern Serra do Espinhaço (Minas Gerais, Brazil were described and sampled from three profiles at 1,250 m (P1, 1,350 m (P4 and

  19. Atmospheric pollutants in alpine peat bogs record a detailed chronology of industrial and agricultural development on the Australian continent

    International Nuclear Information System (INIS)

    Marx, Samuel K.; Kamber, Balz S.; McGowan, Hamish A.; Zawadzki, Atun

    2010-01-01

    Two peat bogs from remote alpine sites in Australia were found to contain detailed and coherent histories of atmospheric metal pollution for Pb, Zn, Cu, Mo, Ag, As, Cd, Sb, Zn, In, Cr, Ni, Tl and V. Dramatic increases in metal deposition in the post-1850 AD portion of the cores coincide with the onset of mining in Australia. Using both Pb isotopes and metals, pollutants were ascribed to the main atmospheric pollution emitting sources in Australia, namely mining and smelting, coal combustion and agriculture. Results imply mining and metal production are the major source of atmospheric metal pollution, although coal combustion may account for up to 30% of metal pollutants. A novel finding of this study is the increase in the otherwise near-constant Y/Ho ratio after 1900 AD. We link this change to widespread and increased application of marine phosphate fertiliser in Australia's main agricultural area (the Murray Darling Basin). - Detailed records of atmospheric metal pollution accumulation in Australia are presented and are shown to trace the industrial and agricultural development of the continent.

  20. Geochemical response of a calcareous fen to road salt contamination during snow melt and precipitation events: Kampoosa Bog, Stockbridge, MA

    Science.gov (United States)

    Rhodes, A. L.; Guswa, A. J.

    2008-12-01

    Kampoosa Bog is the largest and most diverse calcareous lake-basin fen remaining in Massachusetts, and it is one of the state's elite Areas of Critical Environmental Concern (ACEC). The ground water chemistry of the fen has been greatly altered by road salt runoff (NaCl) from the Massachusetts Turnpike, which crosses the northern margin of the wetland complex. Ground water samples collected at different depths within the wetland, measurements of exchangeable Na from an eight-meter core, and hydraulic conductivity measurements suggest that ground water flow and contamination is largely a near- surface phenomenon. Detailed sampling of surface and ground waters during three spring snow melt events and one precipitation event characterizes the geochemical response of the wetland to hydrologic events. Overall, Na:Cl ratios for surface and ground water samples are less than one, and sodium and chloride imbalances suggest that 20-30% of sodium from rock salt is stored on cation exchange sites on organic material. Na:Cl ratios greater than one for fen ground water sampled during Snow Melt 2007 suggest that sodium can be released from cation exchange sites back to ground water under dilute conditions. The total mass of Na and Cl exported from the wetland is greatest under conditions of high discharge. The flux of dissolved salts at the outlet of the fen during Snow Melt 2005 accounts for ~ 24% Na and ~ 32% Cl of rock salt added to the Massachusetts Turnpike during 2004-2005. Estimates of annual fluxes of Na and Cl are on par with the amount of road salt applied, and sodium and chloride concentrations in shallow groundwater have decreased since 2002. The months of March, April and May are the primary months for salt export, accounting for more than half of the annual salt flux in 2005. Concerning the annual net export of sodium and chloride, large rain events may be more important with removing dissolved salts from the fen than snow melt because snow melt also is a time when

  1. Investigating the internal structure of four Azorean Sphagnum bogs using ground-penetrating radar

    Directory of Open Access Journals (Sweden)

    D. Pereira

    2017-08-01

    Full Text Available This study evaluates the applicability of ground penetrating radar (GPR as a technique for determining the thickness and internal structure of four peat deposits on Terceira Island (Azores archipelago, mid-Atlantic region. The peatlands studied are all Sphagnum mires located above 500 m a.s.l., but they differ hydrogenetically and in their degree of naturalness. Radargrams for all four bogs, obtained using both 100 MHz and 500 MHz GPR antennae, are presented and compared. The radargram data were validated against peat characteristics (bulk density, von Post H, US method obtained by direct sampling (‘open cores’ across the whole peat profile at each site. A scheme of ‘soft scoring’ for degree of naturalness (DN of the peatland was developed and used as an additional validation factor. The GPR data were positively correlated with DN, and relationships between GPR data, peat bulk density and degree of humification (H were also found. From the radargrams it was possible to distinguish the interface between the peat and the mineral substratum as well as some of the internal structure of the peat deposit, and thus to derive the total thickness of the peat deposit and (in some cases the thicknesses of its constituent layers. The first evaluation of the propagation velocity of electromagnetic waves in Azorean peat yielded a value of 0.04 m ns-1 for 100 MHz and 500 MHz radar antennae. For one of the study sites, the GPR data were analysed using GIS software to produce tridimensional models and thus to estimate the volumes of peat layers. This type of analysis has potential utility for quantifying some of the ecosystem services provided by peatlands.

  2. Effects of rewetting on greenhouse gas emissions in different microtopes in a cut-over drained bog in Schleswig-Holstein, Germany

    Science.gov (United States)

    Vybornova, Olga; Pfeiffer, Eva-Maria; Kutzbach, Lars

    2016-04-01

    In peatlands, all biogeochemical processes and the amount of exported carbon and nitrogen compounds are strongly influenced by changes in the water table. Peatland drainage leads to increased peat oxidization and changes peatlands from carbon sinks to net carbon sources. Especially, the emissions of the important greenhouse gases (GHG) carbon dioxide, methane and nitrous oxide are increased due to drainage. The currently ongoing restoration in the bog Himmelmoor (N 53° 44'20", E 9° 51'00", Quickborn) with an extent of about 6 km2 one of the largest raised bogs in Schleswig-Holstein, offers the possibility to characterize and to document the development of the fluxes at different sites before, during and after rewetting, using a method of small-scale closed chambers. Six subsites with differing water level and land use were identified: an area that was rewetted 30 years ago with Sphagnum vegetation, an area rewetted in 2009, an area with on-going peat extraction, deep peat cutting ditches refilled with peat with and without Eriophorum angustifolium vegetation and a comparatively dry peat dam. We determined that in the course of years 2014-2015 the measured N2O and CO2 fluxes varied between -0,1 and 1,9 mg m-2 h-1 and between -0,12 and 1,09 g m-2 h-1, respectively, and the highest nitrous oxide as well as carbon dioxide fluxes are typical for the dry peat dam study site. The measured CH4 fluxes were between -1,8 and 22,7 mg m-2 h-1, where the highest rates were found on the area rewetted 30 years ago and on the peat cutting ditches with Eriophorum angustifolium. Accounting for the different global warming potentials (GWP) of the measured greenhouse gases, the annual GHG balance was calculated. Emissions from all study sites ranged between 5,2 and 36 t CO2-eq ha-1 year-1 and were dominated by high emissions of CO2 (2,5 up to 25,5 t CO2-eq ha-1 year-1). Highest emission rates were found at the dry peat dam site and at the area rewetted 30 years ago. The peat dams and

  3. Holocene monsoon variability inferred from Targo Xian peat bog in the Tangra Yumco basin, central Tibetan Plateau

    Science.gov (United States)

    Henkel, Karoline; Haberzettl, Torsten; Miehe, Sabine; Frenzel, Peter; Daut, Gerhard; Dietze, Elisabeth; Kasper, Thomas; Ahlborn, Marieke; Mäusbacher, Roland

    2013-04-01

    The Tibetan Plateau is the greatest plateau on Earth with an average altitude of 4,500 m asl. Due to its high elevation, large area and significant role in the formation of the Asian Monsoon Systems (e.g., Indian Ocean and East-Asian Summer Monsoon) it is considered to react very sensitive to climate variations. The numerous lake systems on the Tibetan Plateau represent excellent archives reflecting variations in the strength of the monsoon system in terms of hydrological changes expressed in lake level fluctuations. For example, terraces and lacustrine deposits around the saline lake Tangra Yumco indicate lake level highstands up to ~215 m higher than the present lake level. To study Holocene lake level variations we investigated a 3.6 m long sediment core recovered from a peat bog (near the Targo Xian settlement, 30°46'N, 86°40'E) on a recessional lake level terrace ~150 m above the present shoreline of Tangra Yumco. In particular, our analyses of sedimentological (grain size), geochemical (CNS and ICP-OES) and mineralogical (XRD) data allow a detailed and high-resolution interpretation of the hydrological conditions during the Holocene. The existence of two carbonate layers in the Targo Xian record, separated by a sand layer and intercalated in peat sequences at the bottom and top of the core, provide evidence for two stable lake stages at the coring position. Peat at the bottom of the core, which is radiocarbon-dated to 11,130 +130/-345 cal BP, indicates wetland conditions similar to the Recent situation (Miehe et al., submitted). After a transition zone, a layer of pure aragonitic lake marl gives evidence for a lake stage. During this stage, high values of the total inorganic carbon (TIC) and Ca/Ti ratios as well as low C/N ratios point to a stable lake due to wet climatic conditions. This carbonate layer can be correlated with a 2-3 m thick carbonate layer found in outcrops around the present lake Tangra Yumco presenting a high lake level until approx. 2

  4. Granulated Bog Iron Ores as Sorbents in Passive (BioRemediation Systems for Arsenic Removal

    Directory of Open Access Journals (Sweden)

    Klaudia Debiec

    2018-03-01

    Full Text Available The main element of PbRS (passive (bioremediation systems are sorbents, which act as natural filters retaining heavy metals and carriers of microorganisms involved in water treatment. Thus, the effectiveness of PbRS is determined by the quality of the (adsorbents, which should be stable under various environmental conditions, have a wide range of applications and be non-toxic to (microorganisms used in these systems. Our previous studies showed that bog iron ores (BIOs meet these requirements. However, further investigation of the physical and chemical parameters of BIOs under environmental conditions is required before their large-scale application in PbRS. The aim of this study was (i to investigate the ability of granulated BIOs (gBIOs to remove arsenic from various types of contaminated waters, and (ii to estimate the application potential of gBIOs in technologies dedicated to water treatment. These studies were conducted on synthetic solutions of arsenic and environmental samples of arsenic contaminated water using a set of adsorption columns filled with gBIOs. The experiments performed in a static system revealed that gBIOs are appropriate arsenic and zinc adsorbent. Dynamic adsorption studies confirmed these results and showed, that the actual sorption efficiency of gBIOs depends on the adsorbate concentration and is directly proportional to them. Desorption analysis showed that As-loaded gBIOs are characterized by high chemical stability and they may be reused for the (adsorption of other elements, i.e., zinc. It was also shown that gBIOs may be used for remediation of both highly oxygenated waters and groundwater or settling ponds, where the oxygen level is low, as both forms of inorganic arsenic (arsenate and arsenite were effectively removed. Arsenic concentration after treatment was <100 μg/L, which is below the limit for industrial water.

  5. Granulated bog iron ores as sorbents in passive (bio)remediation systems for arsenic removal

    Science.gov (United States)

    Debiec, Klaudia; Rzepa, Grzegorz; Bajda, Tomasz; Uhrynowski, Witold; Sklodowska, Aleksandra; Krzysztoforski, Jan; Drewniak, Lukasz

    2018-03-01

    The main element of PbRS (passive (bio)remediation systems) are sorbents, which act as natural filters retaining heavy metals and carriers of microorganisms involved in water treatment. Thus, the effectiveness of PbRS is determined by the quality of the (ad)sorbents, which should be stable under various environmental conditions, have a wide range of applications and be non-toxic to (micro)organisms used in these systems. Our previous studies showed that bog iron ores (BIOs) meet these requirements. However, further investigation of the physical and chemical parameters of BIOs under environmental conditions is required before their large-scale application in PbRS. The aim of this study was (i) to investigate the ability of granulated BIOs (gBIOs) to remove arsenic from various types of contaminated waters, and (ii) to estimate the application potential of gBIOs in technologies dedicated to water treatment. These studies were conducted on synthetic solutions of arsenic and environmental samples of arsenic contaminated water using a set of adsorption columns filled with gBIOs. The experiments performed in a static system revealed that gBIOs are appropriate arsenic and zinc adsorbent. Dynamic adsorption studies confirmed these results and showed that the actual sorption efficiency of gBIOs depends on the adsorbate concentration and is directly proportional to them. Desorption analysis showed that As-loaded gBIOs are characterized by high chemical stability and they may be reused for the (ad)sorption of other elements, i.e. zinc. It was also shown that gBIOs may be used for remediation of both highly oxygenated waters and groundwater or settling ponds, where the oxygen level is low, as both forms of inorganic arsenic (arsenate and arsenite) were effectively removed. Arsenic concentration after treatment was <100 µg/L, which is below the limit for industrial water.

  6. Long-term impacts of peatland restoration on the net ecosystem exchange (NEE) of blanket bogs in Northern Scotland.

    Science.gov (United States)

    Hambley, Graham; Hill, Timothy; Saunders, Matthew; Arn Teh, Yit

    2016-04-01

    Unmanaged peatlands represent an important long-term C sink and thus play an important part of the global C cycle. Despite covering only 12 % of the UK land area, peatlands are estimated to store approximately 20 times more carbon than the UK's forests, which cover 13% of the land area. The Flow Country of Northern Scotland is the largest area of contiguous blanket bog in the UK, and one of the biggest in Europe, covering an area in excess of 4000 km2 and plays a key role in mediating regional atmospheric exchanges of greenhouse gases (GHGs) such as carbon dioxide (CO2), and water vapour (H2O). However, these peatlands underwent significant afforestation in the 1980s, when over 670 km2 of blanket bog were drained and planted with Sitka spruce (Picea sitchensis) and Lodgepole pine (Pinus contorta). This resulted in modifications to hydrology, micro-topography, vegetation and soil properties all of which are known to influence the production, emission and sequestration of key GHGs. Since the late 1990s restoration work has been carried out to remove forest plantations and raise water tables, by drain blocking, to encourage the recolonisation of Sphagnum species and restore ecosystem functioning. Here, we report findings of NEE and its constituent fluxes, GPP and Reco, from a study investigating the impacts of restoration on C dynamics over a chronosequence of restored peatlands. The research explored the role of environmental variables and microtopography in modulating land-atmosphere exchanges, using a multi-scale sampling approach that incorporated eddy covariance measurements with dynamic flux chambers. Key age classes sampled included an undrained peatland; an older restored peatland (17 years old); and a more recently restored site (12 years old). The oldest restored site showed the strongest uptake of C, with an annual assimilation rate of 858 g C m-2 yr-1 compared to assimilation rates of 501g C m-2 yr-1 and 575g C m-2 yr-1 from the younger restored site and

  7. National Program for Inspection of Non-Federal Dams. New Pond Dam (MA 00779), Massachusetts Coastal Basin, Easton, Massachusetts. Phase I Inspection Report.

    Science.gov (United States)

    1981-07-01

    formerly provided irrigation water for the Hammond-Fuller i cranberry bogs. At the present the reservoir continues to service some bogs approximately 2...there are few depressions or irregularities. Vegetation along the edges of the crest consist of short brush, scattered trees up to 22 in. diameter...dam formerly provided irrigation water for cranberry bogs downstream and continues to service some bogs although the owners of the bogs have no

  8. The genesis, stratigraphy and age of Finnish peat deposits. Soiden syntvy, rakenne ja ikae Suomessa

    Energy Technology Data Exchange (ETDEWEB)

    Glueckert, G [Turun yliopisto (Finland). Maaperaegeologian osasto

    1986-01-01

    The genesis, stratigraphy and age of Finnish peat deposits are briefly described. Finnish peats are classified according to their botanical composition to Sphagnum, sedge (Carex) and wood peats. They form complex types of peat land: the ombrotrophic raised bogs in southern Finland and the minerotrophic open sedge (aapa) bogs in northern Finland. The structural bog types in the geological classification are mainly composed of Sphagnum and Carex peats. The raised bogs are predominantly built up of Sphagnum peat, the aapa bogs of Carex peat. The bogs are formed by paludification of lakes, of rising coasts or of low-lying forests. The thickness of peat varies from 3 to 8 m in southern Finland and from 1 to 3 m in northern Finland. The age of the bogs varies according to the uplift of land and the altitude of the bog gasin above sea level. The oldest bogs are 9500-10000 years old and formed in southern and eastern Finland on high-lying upland tracts just after the retreat of the ice at the end of the last glaciation. The geological and palaeontological development of bogs and the history of climate and vegetation can be studied and dated pollenanalytically and with the radiocarbon method.

  9. Testing of in situ and ex situ bioremediation approaches for an oil-contaminated peat bog following a pipeline break

    International Nuclear Information System (INIS)

    Wilson, J.J.; Lee, D.W.; Yeske, B.M.; Kuipers, F.

    2000-01-01

    The feasibility of treating a 1985 pipeline spill of light Pembina Cardium crude oil at a bog near Violet Grove, Alberta was discussed. Pembina Pipeline Corporation arranged for a treatability test to be conducted on oil-contaminated sphagnum peat moss from the site to determine effective in situ or ex situ remediation options for the site. The test was used to evaluate the biodegradation potential of contaminants. Four tests were designed to simulate field different field treatment approaches and to collect critical data on toxicity and leachability of the peat moss. The tests included a bioslurry test, a soil microcosm test, an aerated water saturated peat column test, and a standard toxicity characteristic leachate potential test. The first three tests gave similar results of at least 74 per cent biodegradation of the residual crude oil on the peat solids and no residual toxicity as measured by the Microtox Assay. It was determined that both in situ bioremediation using an aerated water injection system or an ex situ landfarming approach would achieve required criteria and no fertilizers would be necessary to maintain active bioremediation. The new gas-liquid reactor (GLR) aeration technology used in these tests creates a constant supply of hyperoxygenated water prior to column injection. The continuous release of tiny air bubbles maximizes air surface area and increases the gas transfer rates. 3 tabs., 3 figs

  10. Increased transpiration and plant water stress in a black spruce bog exposed to whole ecosystem warming

    Science.gov (United States)

    Warren, J.; Ward, E. J.; Wullschleger, S. D.; Hanson, P. J.

    2017-12-01

    The Spruce and Peatland Responses under Changing Environments (SPRUCE) experiment (http://mnspruce.ornl.gov/) in Northern Minnesota, USA, has exposed 12.8 m diameter plots of an ombrotrophic Picea mariana-Ericaceous shrub bog to whole ecosystem warming (0, +2.25, +4.5, +6.75, +9 °C) since August 2015, and elevated CO2 treatments (ambient or +500 ppm) since June 2016. The mixed-age stand has trees up to 40 year old, and a 5-8 m tall canopy. Thermal dissipation sap flow probes were installed into dominant Picea mariana and Larix laricina trees in each of the 10 open-top chambers in fall 2015. This talk will focus on the first two years of sap flux data from the 10 treatment plots and the relationships with seasonal growth and prevailing environmental conditions. Sap flow was scaled to whole tree and plot level transpiration based on prior in situ calibrations using cut trees, establishment of a sapwood depth: tree diameter relationship, and the tree size distribution within each plot. We also assessed water potential in the trees and two dominant shrubs at the site: Rhododendron groenlandicum and Chamaedaphne calyculata. The warming treatments increased the growing season by up to 6 weeks, with sapflow beginning earlier in spring and lasting later into the fall. The deciduous Larix was the only species exhibiting substantial predawn water stress under the treatments, where water potentials reached -2.5 MPa for the warmest plots. The elevated CO2 reduced midday water stress in the Rhododendron, but not the Chamaedaphne, which could lead to shifts in shrub species composition.

  11. A coherent high-precision radiocarbon chronology for the Late-glacial sequence at Sluggan Bog, Co. Antrim, Northern Ireland

    Science.gov (United States)

    Lowe, J. J.; Walker, M. J. C.; Scott, E. M.; Harkness, D. D.; Bryant, C. L.; Davies, S. M.

    2004-02-01

    Seventy-five radiocarbon dates are presented from Sluggan Bog in Co. Antrim, Northern Ireland. The Holocene peats are underlain by Late-glacial sediments, which also appear to have accumulated largely in a mire environment. The radiocarbon dates, from the Late-glacial and early Holocene part of the profile, were obtained from the humic and humin fractions of the sedimentary matrix, and from plant macrofossils. The last-named were dated by AMS and the sediment samples by radiometric (beta counting) methods. Age-depth models for the three dating series show a very high level of agreement between the two fractions and the macrofossils. No statistically significant difference is found between the beta counting and AMS results. Three tephras were located in the profile, the uppermost of which is in a stratigraphical position suggestive of the Vedde Ash, but the geochemical and radiocarbon evidence do not support this interpretation. The lower ashes are in the correct stratigraphical position for the Laacher See and Borrobol tephras, attributions substantiated by the radiocarbon evidence, but not by the geochemical data. The Sluggan sequence has generated one of the most internally consistent radiocarbon chronologies for any Late-glacial site in the British Isles, and it is suggested that in future more effort should be devoted to the search for, and analysis of, Late-glacial mire sequences, rather than the limnic records that have formed the principal focus of Late-glacial investigations hitherto. Copyright

  12. Andromeda polifolia and Oxycoccus microcarpus as pollution indicators for ombrotrophic bogs in the Western Sudety Mountains (SW Poland).

    Science.gov (United States)

    Wojtuń, Bronisław; Samecka-Cymerman, Aleksandra; Kolon, Krzysztof; Klink, Agnieszka; Kempers, Alexander J

    2013-01-01

    Concentrations of the elements Cd, Cr, Cu, Fe, Li, Mn, N, Ni, Pb and Zn in Andromeda polifolia, Oxycoccus microcarpus and in the peat in which these plants grew were measured in the Western Sudety (Karkonosze and Izerskie Mts., SW Poland). Of both the investigated plant fruit, O. microcarpus harvested from wild populations are commonly used as medicines. Samples from ombrotrophic bogs were investigated within the area influenced by exhausts of the former Black Triangle, one of the most heavily industrialized and polluted areas in Europe. A. polifolia and O. microcarpus growing at the highest elevations contained the highest Cu, Li, Ni, Mn and Zn concentrations and in addition O. microcarpus also contained the highest Cr concentrations. Both the investigated species have wide circumpolar distribution in ombrotrophic mires of the Northern hemisphere. As this type of mires is nourished solely by atmospheric deposition, the increased metal concentrations in A. polifolia and O. microcarpus may be an indication that their habitats receive an atmospheric input of long-range transported pollution. Our investigation proves that both species are able to accumulate elevated metal levels and may be used in the bioindication of the metal status in ombrotrophic mires. Controlling the collection of O. microcarpus fruit for consumption and medicinal purposes is recommended as this species can accumulate increased metal levels. However, further more detailed studies are necessary to verify the inner translocation of metals into fruit.

  13. Peatlands and green frogs: A relationship regulated by acidity?

    Science.gov (United States)

    Mazerolle, M.J.

    2005-01-01

    The effects of site acidification on amphibian populations have been thoroughly addressed in the last decades. However, amphibians in naturally acidic environments, such as peatlands facing pressure from the peat mining industry, have received little attention. Through two field studies and an experiment, I assessed the use of bog habitats by the green frog (Rana clamitans melanota), a species sensitive to various forestry and peat mining disturbances. First, I compared the occurrence and breeding patterns of frogs in bog and upland ponds. I then evaluated frog movements between forest and bog habitats to determine whether they corresponded to breeding or postbreeding movements. Finally, I investigated, through a field experiment, the value of bogs as rehydrating areas for amphibians by offering living Sphagnum moss and two media associated with uplands (i.e., water with pH ca 6.5 and water-saturated soil) to acutely dehydrated frogs. Green frog reproduction at bog ponds was a rare event, and no net movements occurred between forest and bog habitats. However, acutely dehydrated frogs did not avoid Sphagnum. Results show that although green frogs rarely breed in bogs and do not move en masse between forest and bog habitats, they do not avoid bog substrates for rehydrating, despite their acidity. Thus, bogs offer viable summering habitat to amphibians, which highlights the value of these threatened environments in terrestrial amphibian ecology.

  14. Anthropogenic impacts in North Poland over the last 1300 years - A record of Pb, Zn, Cu, Ni and S in an ombrotrophic peat bog

    International Nuclear Information System (INIS)

    De Vleeschouwer, Francois; Fagel, Nathalie; Cheburkin, Andriy; Pazdur, Anna; Sikorski, Jaroslaw; Mattielli, Nadine; Renson, Virginie; Fialkiewicz, Barbara; Piotrowska, Natalia; Le Roux, Gael

    2009-01-01

    Lead pollution history over Northern Poland was reconstructed for the last ca. 1300 years using the elemental and Pb isotope geochemistry of a dated Polish peat bog. The data show that Polish Pb-Zn ores and coal were the main sources of Pb, other heavy metals and S over Northern Poland up until the industrial revolution. After review of the potential mobility of each element, most of the historical interpretation was based on Pb and Pb isotopes, the other chemical elements (Zn, Cu, Ni, S) being considered secondary indicators of pollution. During the last century, leaded gasoline also contributed to anthropogenic Pb pollution over Poland. Coal and Pb-Zn ores, however, remained important sources of pollution in Eastern European countries during the last 50 years, as demonstrated by a high 206 Pb/ 207 Pb ratio (1.153) relative to that of Western Europe (ca. 1.10). The Pb data for the last century were also in good agreement with modelled Pb inventories over Poland and the Baltic region.

  15. Biomass, productivity and relative rate of photosynthesis of sphagnum at different water levels on a South Swedish peat bog

    International Nuclear Information System (INIS)

    Wallen, B.; Falkengren-Grerup, U.; Malmer, N.

    1988-01-01

    The distribution pattern of Spaghnum species on bogs follows a hummock-hollow gradient. S. Sect. Acutifolia (that is in this study S. Fuscum and S. rubellum combined) dominates hummock tops, ca 20 cm above the maximum water level with a green biomass of 50 g m --2 , S. magellanicum dominates at a lower level, about 5 cm above the water level with a green biomass of 75 g m -2 and S. cuspidatum dominates in the wettest hollows with a green biomass of about 50 g m -2 . In situ measurements of length growth of S. Sect. Acutifolia and S. magelanicum using a 14 CO 2 -labelling technique during three consecutive years, revealed an unexpectedly high between-year variation in length growth of 7-23 mm yr -1 , and 16-22 mm yr -1 , respectively. Consequently the dominating producer in the transition between hummock and hollow changes from year to year, probably depending on climatic conditions. In vitro experiments on the effects of different water levels of 2, 5, 10 and 20 cm below the moss surface, on photosynthetic activity of S. Sect. Acutifolia and S. magellanicum, measured by a second 14 CO 2 -technique, indicate optimal conditions for S. magellanicum at 10 cm above water level, and for S. Sect, Acutofolia at 20 cm above water level. Differences in capillary water transport capability between the species are more important than the sensitivity of photosynthesis to water stress in explaining field patterns of productivity and distribution

  16. Sphagnum-dominated bog systems are highly effective yet variable sources of bio-available iron to marine waters.

    Science.gov (United States)

    Krachler, Regina; Krachler, Rudolf F; Wallner, Gabriele; Steier, Peter; El Abiead, Yasin; Wiesinger, Hubert; Jirsa, Franz; Keppler, Bernhard K

    2016-06-15

    Iron is a micronutrient of particular interest as low levels of iron limit primary production of phytoplankton and carbon fluxes in extended regions of the world's oceans. Sphagnum-peatland runoff is extraordinarily rich in dissolved humic-bound iron. Given that several of the world's largest wetlands are Sphagnum-dominated peatlands, this ecosystem type may serve as one of the major sources of iron to the ocean. Here, we studied five near-coastal creeks in North Scotland using freshwater/seawater mixing experiments of natural creek water and synthetic seawater based on a (59)Fe radiotracer technique combined with isotopic characterization of dissolved organic carbon by Accelerator Mass Spectrometry. Three of the creeks meander through healthy Sphagnum-dominated peat bogs and the two others through modified peatlands which have been subject to artificial drainage for centuries. The results revealed that, at the time of sampling (August 16-24, 2014), the creeks that run through modified peatlands delivered 11-15μg iron per liter creek water to seawater, whereas the creeks that run through intact peatlands delivered 350-470μg iron per liter creek water to seawater. To find out whether this humic-bound iron is bio-available to marine algae, we performed algal growth tests using the unicellular flagellated marine prymnesiophyte Diacronema lutheri and the unicellular marine green alga Chlorella salina, respectively. In both cases, the riverine humic material provided a highly bio-available source of iron to the marine algae. These results add a new item to the list of ecosystem services of Sphagnum-peatlands. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

  17. Bog bilberry (Vaccinium uliginosum L.) extract reduces cultured Hep-G2, Caco-2, and 3T3-L1 cell viability, affects cell cycle progression, and has variable effects on membrane permeability.

    Science.gov (United States)

    Liu, Jia; Zhang, Wei; Jing, Hao; Popovich, David G

    2010-04-01

    Bog bilberry (Vaccinium uliginosum L.) is a blue-pigmented edible berry related to bilberry (Vaccinium myrtillus L.) and the common blueberry (Vaccinium corymbosum). The objective of this study was to investigate the effect of a bog bilberry anthocyanin extract (BBAE) on cell growth, membrane permeability, and cell cycle of 2 malignant cancer cell lines, Caco-2 and Hep-G2, and a nonmalignant murine 3T3-L1 cell line. BBAE contained 3 identified anthocyanins. The most abundant anthocyanin was cyanidin-3-glucoside (140.9 +/- 2.6 microg/mg of dry weight), followed by malvidin-3-glucoside (10.3 +/- 0.3 microg/mg) and malvidin-3-galactoside (8.1 +/- 0.4 microg/mg). Hep-G2 LC50 was calculated to be 0.563 +/- 0.04 mg/mL, Caco-2 LC50 was 0.390 +/- 0.30 mg/mL and 0.214 +/- 0.02 mg/mL for 3T3-L1 cells. LDH release, a marker of membrane permeability, was significantly increased in Hep-G2 cells and Caco-2 cells after 48 and 72 h compared to 24 h. The increase was 21% at 48 h and 57% at 72 h in Caco-2 cells and 66% and 139% in Hep-G2 cells compared to 24 h. However, 3T3-L1 cells showed an unexpected significant lower LDH activity (P < or = 0.05) after 72 h of exposure corresponding to a 21% reduction in LDH release. BBAE treatment increased sub-G1 in all 3 cell lines without influencing cells in the G2/M phase. BBAE treatment reduced the growth and increased the accumulation of sub-G1 cells in 2 malignant and 1 nonmalignant cell line; however, the effect on membrane permeability differs considerably between the malignant and nonmalignant cells and may in part be due to differences in cellular membrane composition.

  18. Enhancement of energy performance in a boil-off gas re-liquefaction system of LNG carriers using ejectors

    International Nuclear Information System (INIS)

    Tan, Hongbo; Zhao, Qingxuan; Sun, Nannan; Li, Yanzhong

    2016-01-01

    Highlights: • An ejector-enhanced LNG boil-off gas (BOG) re-liquefaction system is proposed. • The new system has an improvement of 28% in COP over the existing system. • The specific energy consumption of the new system is reduced to 0.59 kW h/kg(BOG). • The power consumption of 754.1 kW is saved in the case study. - Abstract: An ejector-enhanced Liquefied Natural Gas (LNG) boil-off gas (BOG) re-liquefaction system is proposed to improve the energy efficiency of the existing system. In the new system, two ejectors are respectively used to reduce the energy loss in the expansion of the pressurized BOG and inject a part of fuel BOG into the compression system, and a recuperator is employed to recover the cold energy of the BOG exited from LNG tank. The performance improvement of the proposed system is analysed on the basis of the simulation in Aspen HYSYS. In the case of the re-liquefaction capacity of 4557.6 kg/h, the coefficient of performance (COP) and exergy efficiency can be increased by 28%, and the specific energy consumption (SEC) reduced from 0.756 to 0.59 kW h/kg(BOG) compared to the conventional BOG re-liquefaction system. Correspondingly, the power consumption of 754.1 kW is saved. This means that applying ejectors can effectively improve the energy efficiency of the existing BOG re-liquefaction system for LNG carriers.

  19. A Novel Boil-Off Gas Re-Liquefaction Using a Spray Recondenser for Liquefied Natural-Gas Bunkering Operations

    Directory of Open Access Journals (Sweden)

    Jiheon Ryu

    2016-11-01

    Full Text Available This study presents the design of a novel boil-off gas (BOG re-liquefaction technology using a BOG recondenser system. The BOG recondenser system targets the liquefied natural gas (LNG bunkering operation, in which the BOG phase transition occurs in a pressure vessel instead of a heat exchanger. The BOG that is generated during LNG bunkering operation is characterized as an intermittent flow with various peak loads. The system was designed to temporarily store the transient BOG inflow, condense it with subcooled LNG and store the condensed liquid. The superiority of the system was verified by comparing it with the most extensively employed conventional re-liquefaction system in terms of consumption energy and via an exergy analysis. Static simulations were conducted for three compositions; the results indicated that the proposed system provided 0 to 6.9% higher efficiencies. The exergy analysis indicates that the useful work of the conventional system is 24.9%, and the useful work of the proposed system is 26.0%. Process dynamic simulations of six cases were also performed to verify the behaviour of the BOG recondenser system. The results show that the pressure of the holdup in the recondenser vessel increased during the BOG inflow mode and decreased during the initialization mode. The maximum pressure of one of the bunkering cases was 3.45 bar. The system encountered a challenge during repetitive operations due to overpressurizing of the BOG recondenser vessel.

  20. Ecology of Coom Rigg Moss, Northumberland. I. Stratigraphy and present vegetation

    Energy Technology Data Exchange (ETDEWEB)

    Chapman, S B

    1964-01-01

    A description is given of Coom Rigg Moss, a bog in Northumberland. Evidence from peat stratigraphy and pollen analysis distinguishes two main types of peat profile, a raised bog type and a blanket bog type. It is shown that fen peat formation began in hollows (zone VI) then became covered with alder-birch carr in zone VIIa and that the whole area was covered with peat by the beginning of zone VIIb. These conditions have produced a bog system at the present time that can best be described as centres of raised bog development now united by blanket peat formation. The vegetation of the bog surface is described and it is shown that two types of vegetation occur, one containing more Sphagnum magnum magellanicum than S. papillosum, confined to areas where it is subjected to a flushing effect, and the other containing more S. papillosum than S. magellanicum, being more typical of the greater part of the bog surface. It is shown that plants of phragmites still growing on the bog surface are relics from previous vegetation and that they have gradually been restricted in their distribution. It suggested that relative isolation and freedom from damage by grazing, burning and drainage have allowed this site to continue in a state of active peat accumulation.

  1. An Antarctic hypotrichous ciliate, Parasterkiella thompsoni (Foissner) nov. gen., nov. comb., recorded in Argentinean peat-bogs: morphology, morphogenesis, and molecular phylogeny.

    Science.gov (United States)

    Küppers, Gabriela Cristina; Paiva, Thiago da Silva; Borges, Bárbara do Nascimento; Harada, Maria Lúcia; Garraza, Gabriela González; Mataloni, Gabriela

    2011-05-01

    The ciliate Parasterkiella thompsoni (Foissner, 1996) nov. gen., nov. comb. was originally described from Antarctica. In the present study, we report the morphology, morphogenesis during cell division, and molecular phylogeny inferred from the 18S-rDNA sequence of a population isolated from the Rancho Hambre peat bog, Tierra del Fuego Province (Argentina). The study is based on live and protargol-impregnated specimens. Molecular phylogeny was inferred from trees constructed by means of the maximum parsimony, neighbor joining, and Bayesian analyses. The interphase morphology matches the original description of the species. During the cell division, stomatogenesis begins with the de novo proliferation of two fields of basal bodies, each one left of the postoral ventral cirri and of transverse cirri, which later unify. Primordia IV-VI of the proter develop from disaggregation of cirrus IV/3, while primordium IV of the opisthe develops from cirrus IV/2 and primordia V and VI from cirrus V/4. Dorsal morphogenesis occurs in the Urosomoida pattern-that is, the fragmentation of kinety 3 is lacking. Three macronuclear nodules are generated before cytokinesis. Phylogenetic analyses consistently placed P. thompsoni within the stylonychines. New data on the morphogenesis of the dorsal ciliature justifies the transference of Sterkiella thompsoni to a new genus Parasterkiella. Copyright © 2011 Elsevier GmbH. All rights reserved.

  2. Mining for Nonribosomal Peptide Synthetase and Polyketide Synthase Genes Revealed a High Level of Diversity in the Sphagnum Bog Metagenome.

    Science.gov (United States)

    Müller, Christina A; Oberauner-Wappis, Lisa; Peyman, Armin; Amos, Gregory C A; Wellington, Elizabeth M H; Berg, Gabriele

    2015-08-01

    Sphagnum bog ecosystems are among the oldest vegetation forms harboring a specific microbial community and are known to produce an exceptionally wide variety of bioactive substances. Although the Sphagnum metagenome shows a rich secondary metabolism, the genes have not yet been explored. To analyze nonribosomal peptide synthetases (NRPSs) and polyketide synthases (PKSs), the diversity of NRPS and PKS genes in Sphagnum-associated metagenomes was investigated by in silico data mining and sequence-based screening (PCR amplification of 9,500 fosmid clones). The in silico Illumina-based metagenomic approach resulted in the identification of 279 NRPSs and 346 PKSs, as well as 40 PKS-NRPS hybrid gene sequences. The occurrence of NRPS sequences was strongly dominated by the members of the Protebacteria phylum, especially by species of the Burkholderia genus, while PKS sequences were mainly affiliated with Actinobacteria. Thirteen novel NRPS-related sequences were identified by PCR amplification screening, displaying amino acid identities of 48% to 91% to annotated sequences of members of the phyla Proteobacteria, Actinobacteria, and Cyanobacteria. Some of the identified metagenomic clones showed the closest similarity to peptide synthases from Burkholderia or Lysobacter, which are emerging bacterial sources of as-yet-undescribed bioactive metabolites. This report highlights the role of the extreme natural ecosystems as a promising source for detection of secondary compounds and enzymes, serving as a source for biotechnological applications. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  3. Methylocapsa acidiphila gen. nov., sp. nov., a novel methane-oxidizing and dinitrogen-fixing acidophilic bacterium from Sphagnum bog.

    Science.gov (United States)

    Dedysh, Svetlana N; Khmelenina, Valentina N; Suzina, Natalia E; Trotsenko, Yuri A; Semrau, Jeremy D; Liesack, Werner; Tiedje, James M

    2002-01-01

    A novel genus and species, Methylocapsa acidiphila gen. nov., sp. nov., are proposed for a methane-oxidizing bacterium isolated from an acidic Sphagnum peat bog. This bacterium, designated strain B2T, represents aerobic, gram-negative, colourless, non-motile, curved coccoids that form conglomerates covered by an extracellular polysaccharide matrix. The cells use methane and methanol as sole sources of carbon and energy and utilize the serine pathway for carbon assimilation. Strain B2T is a moderately acidophilic organism with growth between pH 4.2 and 7.2 and at temperatures from 10 to 30 degrees C. The cells possess a well-developed system of intracytoplasmic membranes (ICM) packed in parallel on only one side of the cell membrane. This type of ICM structure represents a novel arrangement, which was termed type III. The resting cells are Azotobacter-type cysts. Strain B2T is capable of atmospheric nitrogen fixation; it possesses particulate methane monooxygenase and does not express soluble methane monooxygenase. The major phospholipid fatty acid is 18:1omega7c and the major phospholipids are phosphatidylglycerols. The G+C content of the DNA is 63.1 mol%. This bacterium belongs to the alpha-subclass of the Proteobacteria and is most closely related to the acidophilic methanotroph Methylocella palustris KT (97.3% 16S rDNA sequence similarity). However, the DNA-DNA hybridization value between strain B2T and Methylocella palustris K(T) is only 7%. Thus, strain B2T is proposed to comprise a novel genus and species, Methylocapsa acidiphila gen. nov., sp. nov. Strain B2T (= DSM 13967T = NCIMB 13765T) is the type strain.

  4. Historical accumulation rates of mercury in four Scottish ombrotrophic peat bogs over the past 2000 years

    Energy Technology Data Exchange (ETDEWEB)

    Farmer, John G., E-mail: J.G.Farmer@ed.ac.uk [School of GeoSciences, University of Edinburgh, Edinburgh, EH9 3JN, Scotland (United Kingdom); Anderson, Peter [Contaminated Land Assessment and Remediation Research Centre, University of Edinburgh, Edinburgh, EH9 3JL, Scotland (United Kingdom); Cloy, Joanna M.; Graham, Margaret C. [School of GeoSciences, University of Edinburgh, Edinburgh, EH9 3JN, Scotland (United Kingdom); MacKenzie, Angus B.; Cook, Gordon T. [Scottish Universities Environmental Research Centre, East Kilbride, G75 0QF, Scotland (United Kingdom)

    2009-10-15

    The historical accumulation rates of mercury resulting from atmospheric deposition to four Scottish ombrotrophic peat bogs, Turclossie Moss (northeast Scotland), Flanders Moss (west-central), Red Moss of Balerno (east-central) and Carsegowan Moss (southwest), were determined via analysis of {sup 210}Pb- and {sup 14}C-dated cores up to 2000 years old. Average pre-industrial rates of mercury accumulation of 4.5 and 3.7 {mu}g m{sup -2} y{sup -1} were obtained for Flanders Moss (A.D. 1-1800) and Red Moss of Balerno (A.D. 800-1800), respectively. Thereafter, mercury accumulation rates increased to typical maximum values of 51, 61, 77 and 85 {mu}g m{sup -2} y{sup -1}, recorded at different times possibly reflecting local/regional influences during the first 70 years of the 20th century, at the four sites (TM, FM, RM, CM), before declining to a mean value of 27 {+-} 15 {mu}g m{sup -2} y{sup -1} during the late 1990s/early 2000s. Comparison of such trends for mercury with those for lead and arsenic in the cores and also with direct data for the declining UK emissions of these three elements since 1970 suggested that a substantial proportion of the mercury deposited at these sites over the past few decades originated from outwith the UK, with contributions to wet and dry deposition arising from long-range transport of mercury released by sources such as combustion of coal. Confidence in the chronological reliability of these core-derived trends in absolute and relative accumulation of mercury, at least since the 19th century, was provided by the excellent agreement between the corresponding detailed and characteristic temporal trends in the {sup 206}Pb/{sup 207}Pb isotopic ratio of lead in the {sup 210}Pb-dated Turclossie Moss core and those in archival Scottish Sphagnum moss samples of known date of collection. The possibility of some longer-term loss of volatile mercury released from diagenetically altered older peat cannot, however, be excluded by the findings of this

  5. Historical accumulation rates of mercury in four Scottish ombrotrophic peat bogs over the past 2000 years

    International Nuclear Information System (INIS)

    Farmer, John G.; Anderson, Peter; Cloy, Joanna M.; Graham, Margaret C.; MacKenzie, Angus B.; Cook, Gordon T.

    2009-01-01

    The historical accumulation rates of mercury resulting from atmospheric deposition to four Scottish ombrotrophic peat bogs, Turclossie Moss (northeast Scotland), Flanders Moss (west-central), Red Moss of Balerno (east-central) and Carsegowan Moss (southwest), were determined via analysis of 210 Pb- and 14 C-dated cores up to 2000 years old. Average pre-industrial rates of mercury accumulation of 4.5 and 3.7 μg m -2 y -1 were obtained for Flanders Moss (A.D. 1-1800) and Red Moss of Balerno (A.D. 800-1800), respectively. Thereafter, mercury accumulation rates increased to typical maximum values of 51, 61, 77 and 85 μg m -2 y -1 , recorded at different times possibly reflecting local/regional influences during the first 70 years of the 20th century, at the four sites (TM, FM, RM, CM), before declining to a mean value of 27 ± 15 μg m -2 y -1 during the late 1990s/early 2000s. Comparison of such trends for mercury with those for lead and arsenic in the cores and also with direct data for the declining UK emissions of these three elements since 1970 suggested that a substantial proportion of the mercury deposited at these sites over the past few decades originated from outwith the UK, with contributions to wet and dry deposition arising from long-range transport of mercury released by sources such as combustion of coal. Confidence in the chronological reliability of these core-derived trends in absolute and relative accumulation of mercury, at least since the 19th century, was provided by the excellent agreement between the corresponding detailed and characteristic temporal trends in the 206 Pb/ 207 Pb isotopic ratio of lead in the 210 Pb-dated Turclossie Moss core and those in archival Scottish Sphagnum moss samples of known date of collection. The possibility of some longer-term loss of volatile mercury released from diagenetically altered older peat cannot, however, be excluded by the findings of this study.

  6. Anmeldelse af Kristiansen, S. (2005). Kvalitativ dataanalyse og software - en introduktion til Nvivo

    DEFF Research Database (Denmark)

    Musaeus, Peter

    2005-01-01

    En anmdelse af en brugervenlig bog om Nvivo (QSR Nvivo), der er en videreudvikling af NUD*IST. Herværende bog, der er den første af sin slags på dansk, diskuteres i forhold til dens introduktion til Nvivo. Udgivelsesdato: december......En anmdelse af en brugervenlig bog om Nvivo (QSR Nvivo), der er en videreudvikling af NUD*IST. Herværende bog, der er den første af sin slags på dansk, diskuteres i forhold til dens introduktion til Nvivo. Udgivelsesdato: december...

  7. Stratigraphy and chronology of a 15 ka sequence of multi-sourced silicic tephras in a montane peat bog, eastern North Island, New Zealand

    International Nuclear Information System (INIS)

    Lowe, D.J.; Newnham, R.M.; Ward, C.M.

    1999-01-01

    We document the stratigraphy, composition, and chronology of a succession of 16 distal, silicic tephra layers interbedded with lateglacial and Holocene peats and muds up to c. 15 000 radiocarbon years (c. 18 000 calendar years) old at a montane site (Kaipo Bog) in eastern North Island, New Zealand. Aged from 665 + or - 15 to 14 700 + or - 95 14 C yr BP, the tephras are derived from six volcanic centres in North Island, three of which are rhyolitic (Okataina, Taupo, Maroa), one peralkaline (Tuhua), and two andesitic (Tongariro, Egmont). Correlations are based on multiple criteria: field properties and stratigraphic interrelationships, ferromagnesian silicate mineral assemblages, glass-shard major element composition (from electron microprobe analysis), and radiocarbon dating. We extend the known distribution of tephras in eastern North Island and provide compositional data that add to their potential usefulness as isochronous markers. The chronostratigraphic framework established for the Kaipo sequence, based on both site-specific and independently derived tephra-based radiocarbon ages, provides the basis for fine-resolution paleoenvironmental studies at a climatically sensitive terrestrial site from the mid latitudes of the Southern Hemisphere. Tephras identified as especially useful paleoenvironmental markers include Rerewhakaaitu and Waiohau (lateglacial), Konini (late-glacial-early Holocene), Tuhua (middle Holocene), and Taupo and Kaharoa (late Holocene). (author). 102 refs., 3 tabs., 3 figs

  8. Halogens in pore water of peat bogs – the role of peat decomposition and dissolved organic matter

    Directory of Open Access Journals (Sweden)

    H. Biester

    2006-01-01

    Full Text Available Halogens are strongly enriched in peat and peatlands and such they are one of their largest active terrestrial reservoir. The enrichment of halogens in peat is mainly attributed to the formation of organohalogens and climatically controlled humification processes. However, little is known about release of halogens from the peat substrate and the distribution of halogens in the peat pore water. In this study we have investigated the distribution of chlorine, bromine and iodine in pore water of three pristine peat bogs located in the Magellanic Moorlands, southern Chile. Peat pore waters were collected using a sipping technique, which allows in situ sampling down to a depth greater than 6m. Halogens and halogen species in pore water were determined by ion-chromatography (IC (chlorine and IC-ICP-MS (bromine and iodine. Results show that halogen concentrations in pore water are 15–30 times higher than in rainwater. Mean concentrations of chlorine, bromine and iodine in pore water were 7–15 mg l−1, 56–123 μg l−1, and 10–20 μg l−1, which correspond to mean proportions of 10–15%, 1–2.3% and 0.5–2.2% of total concentrations in peat, respectively. Organobromine and organoiodine were the predominant species in pore waters, whereas chlorine in pore water was mostly chloride. Advection and diffusion of halogens were found to be generally low and halogen concentrations appear to reflect release from the peat substrate. Release of bromine and iodine from peat depend on the degree of peat degradation, whereas this relationship is weak for chlorine. Relatively higher release of bromine and iodine was observed in less degraded peat sections, where the release of dissolved organic carbon (DOC was also the most intensive. It has been concluded that the release of halogenated dissolved organic matter (DOM is the predominant mechanism of iodine and bromine release from peat.

  9. Methane ebullition fluxes from northern peatlands: initial observations from four sites of contrasting vegetation type in Caribou Bog, ME

    Science.gov (United States)

    Slater, L. D.; Comas, X.; Mumford, K. G.; Reeve, A. S.; Varner, R. K.; Chen, X.; Wright, W.; Wright, J.; Molnar, I. L.; Krol, M.

    2017-12-01

    The contribution of peatlands to the atmospheric CH4 burden remains unclear in large part due to incomplete understanding of the ebullition pathway. Oxidation of dissolved methane reduces the release of methane by diffusion, but the transit time of bubbles released via ebullition is too short for extensive oxidation to occur, i.e. ebullition releases increase the greenhouse gas potential of peatlands. We are working to couple innovative strategies for ebullition monitoring with a physical model describing gas transport in terms of the mechanical properties of the peat. This integration of measurement and modeling will permit a fundamental step forward towards a more quantitative understanding of CH4 ebullition from peatlands. Sampling and sensor installation have been performed in Caribou Bog, a multi-unit peatland located in Maine (USA) where an extensive database accounting for a decade of research is already available from previous work examining methane dynamics. Multi-depth gas trap and moisture probe arrays have been installed at four sites selected based on contrasting vegetation type and peat basin depth determined from extensive ground penetrating radar surveys. Hydraulic head measurements have also been acquired on multi-level piezometers designed to capture transient signals associated with gas transport. Cores and initial field observations acquired in summer 2017 confirm that the physical properties of the peat vary markedly between the sites and influence gas storage and release. An existing ebullition model describing gas bubble expansion is being coupled with an invasion percolation approach to describe the transport of CH4 between multiple peat layers by both diffusion in the pore water and ebullition between layers. Although the proposed model does not explicitly incorporate the geomechanical properties of peat, model predictions for maximum gas contents are being compared with key measurable geomechanical properties (including measured capillary

  10. Seasonal Oxygen Dynamics in a Thermokarst Bog in Interior Alaska: Implications for Rates of Methane Oxidation

    Science.gov (United States)

    Neumann, R. B.; Moorberg, C.; Wong, A.; Waldrop, M. P.; Turetsky, M. R.

    2015-12-01

    Methane is a potent greenhouse gas, and wetlands represent the largest natural source of methane to the atmosphere. However, much of the methane generated in anoxic wetlands never gets emitted to the atmosphere; up to >90% of generated methane can get oxidized to carbon dioxide. Thus, oxidation is an important methane sink and changes in the rate of methane oxidation can affect wetland methane emissions. Most methane is aerobically oxidized at oxic-anoxic interfaces where rates of oxidation strongly depend on methane and oxygen concentrations. In wetlands, oxygen is often the limiting substrate. To improve understanding of belowground oxygen dynamics and its impact on methane oxidation, we deployed two planar optical oxygen sensors in a thermokarst bog in interior Alaska. Previous work at this site indicated that, similar to other sites, rates of methane oxidation decrease over the growing season. We used the sensors to track spatial and temporal patterns of oxygen concentrations over the growing season. We coupled these in-situ oxygen measurements with periodic oxygen injection experiments performed against the sensor to quantify belowground rates of oxygen consumption. We found that over the season, the thickness of the oxygenated water layer at the peatland surface decreased. Previous research has indicated that in sphagnum-dominated peatlands, like the one studied here, rates of methane oxidation are highest at or slightly below the water table. It is in these saturated but oxygenated locations that both methane and oxygen are available. Thus, a seasonal reduction in the thickness of the oxygenated water layer could restrict methane oxidation. The decrease in thickness of the oxygenated layer coincided with an increase in the rate of oxygen consumption during our oxygen injection experiments. The increase in oxygen consumption was not explained by temperature; we infer it was due to an increase in substrate availability for oxygen consuming reactions and

  11. Design of a boil-off natural gas reliquefaction control system for LNG carriers

    International Nuclear Information System (INIS)

    Shin, Younggy; Lee, Yoon Pyo

    2009-01-01

    Onboard boil-off gas (BOG) reliquefaction is a new technology that liquefies BOG and returns it to the cargo tanks instead of burning it off during a voyage. For the commercial development of this technology, an object-oriented dynamic simulation is presented which facilitates the design of the plant and control system for the thermal process. A reliquefaction process based on the reverse Brayton cycle has been designed, and its static thermodynamic states at the design BOG load are presented. To make the cycle work for any BOG load, an idea was sought that would achieve a heat balance with the work extracted by the expander. Dynamic simulations were conducted for all operating modes, including start-up and idle. It was found that the expander exit temperature is the key process variable for control and that the process control works successfully when three actuators are activated in three different BOG load regimes. The study also shows that control of the separator pressure to keep the vapor fraction at the throttle valve exit as low as possible is an efficient method for purging nitrogen from BOG

  12. Bringing back the rare - biogeochemical constraints of peat moss establishment in restored cut-over bogs

    Science.gov (United States)

    Raabe, Peter; Blodau, Christian; Hölzel, Norbert; Kleinebecker, Till; Knorr, Klaus-Holger

    2016-04-01

    In rewetted cut-over bogs in north-western Germany and elsewhere almost no spontaneous recolonization of hummock peat mosses, such as Sphagnum magellanicum, S. papillosum or S. rubellum can be observed. However, to reach goals of climate protection every restoration of formerly mined peatlands should aim to enable the re-establishment of these rare but functionally important plant species. Besides aspects of biodiversity, peatlands dominated by mosses can be expected to emit less methane compared to sites dominated by graminoids. To assess the hydrological and biogeochemical factors constraining the successful establishment of hummock Sphagnum mosses we conducted a field experiment by actively transferring hummock species into six existing restoration sites in the Vechtaer Moor, a large peatland complex with active peat harvesting and parallel restoration efforts. The mosses were transferred as intact sods in triplicate at the beginning of June 2016. Six weeks (mid-July) and 18 weeks later (beginning of October) pore water was sampled in two depths (5 and 20 cm) directly beneath the inoculated Sphagnum sods as well as in untreated control plots and analysed for phosphate, ferrous iron, ammonia, nitrate and total organic carbon (TOC). On the same occasions and additionally in December, the vitality of mosses was estimated. Furthermore, the increment of moss height between July and December was measured by using cranked wires and peat cores were taken for lab analyses of nutrients and major element inventories at the depths of pore water sampling. Preliminary results indicate that vitality of mosses during the period of summer water level draw down was strongly negatively related to plant available phosphate in deeper layers of the residual peat. Furthermore, increment of moss height was strongly negatively related to TOC in the upper pore waters sampled in October. Concentration of ferrous iron in deeper pore waters was in general significantly higher beneath

  13. Multivariate study of trace element distribution in the geological record of Roñanzas Peat Bog (Asturias, N. Spain). Paleoenvironmental evolution and human activities over the last 8000 calyr BP.

    Science.gov (United States)

    Gallego, José Luis R; Ortiz, José E; Sierra, Carlos; Torres, Trinidad; Llamas, J F

    2013-06-01

    Trace element concentrations in the Roñanzas peat bog record reveal a contribution of natural processes but the influence of anthropogenic factors predominates in the last two millenniums, particularly aerosol deposition linked to mining and industrial activities in northern Spain. We observed that the Roñanzas record can be considered a preserved environment, suitable to search for local (major elements. Our study design represents a novel approach to assign natural vs. human contributions in peatlands. Therefore, synergies obtained by the simultaneous study of multivariate statistics and enrichment factors allow robust conclusions about paleoenvironmental evolution and human activities. Anthropogenic influence has also been reported in similar records in other parts of Europe, thereby suggesting large-scale sources for atmospheric pollution. However, here we revealed remarkable particularities, such as the association of Cd, Zn and Pb, mainly linked to regional and local factors (mining and more recently the metallurgical industry), whereas we propose that the occurrence of Hg is associated with a combination of regional factors and global atmospheric pollution. Copyright © 2013 Elsevier B.V. All rights reserved.

  14. The Acid-Base Balance Between Organic Acids and Circumneutral Ground Waters in Large Peatlands

    Science.gov (United States)

    Siegel, D. I.; Glaser, P. H.; So, J.

    2006-05-01

    Organic acids supply most of the acidity in the surface waters of bogs in peatlands. Yet, the fundamental geochemical properties of peatland organic acids are still poorly known. To assess the geochemical properties of typical organic acid assemblages in peatlands, we used a triprotic analog model for peat pore waters and surface waters in the Glacial Lake Agassiz Peatlands, optimizing on charge balance and calibrated to estimates of mole site density in DOC and triprotic acid dissociation constants. Before the calibration process, all bog waters and 76% of fen waters had more than +20% charge imbalance. After calibration, most electrochemically balanced within 20%. In the best calibration, the mole site denisty of bog DOC was estimated as ~0.05 mmol/mmol C., approximately 6 times smaller than that for fen DOC or the DOC in the fen deeper fen peats that underlie bogs. The three modeled de-protonation constants were; pKa1 = ~3.0, pKa2 = ~4.5 and pKa3 = ~7.0 for the bog DOC, and; pKa1 = ~5.2, pKa2 =~ 6.5 and pKa3 = ~7.0 for the fen DOC. Bog DOC, behaves as a strong acid despite its small mole site density. The DOC in bog runoff can therefore theoretically acidify the surface waters in adjacent fens wherever these waters do not receive sufficient buffering alkalinity from active groundwater seepage.

  15. The effects of permafrost thaw on soil hydrologic, thermal, and carbon dynamics in an Alaskan peatland

    Science.gov (United States)

    O'Donnell, Jonathan A.; Jorgenson, M. Torre; Harden, Jennifer W.; McGuire, A. David; Kanevskiy, Mikhail Z.; Wickland, Kimberly P.

    2012-01-01

    Recent warming at high-latitudes has accelerated permafrost thaw in northern peatlands, and thaw can have profound effects on local hydrology and ecosystem carbon balance. To assess the impact of permafrost thaw on soil organic carbon (OC) dynamics, we measured soil hydrologic and thermal dynamics and soil OC stocks across a collapse-scar bog chronosequence in interior Alaska. We observed dramatic changes in the distribution of soil water associated with thawing of ice-rich frozen peat. The impoundment of warm water in collapse-scar bogs initiated talik formation and the lateral expansion of bogs over time. On average, Permafrost Plateaus stored 137 ± 37 kg C m-2, whereas OC storage in Young Bogs and Old Bogs averaged 84 ± 13 kg C m-2. Based on our reconstructions, the accumulation of OC in near-surface bog peat continued for nearly 1,000 years following permafrost thaw, at which point accumulation rates slowed. Rapid decomposition of thawed forest peat reduced deep OC stocks by nearly half during the first 100 years following thaw. Using a simple mass-balance model, we show that accumulation rates at the bog surface were not sufficient to balance deep OC losses, resulting in a net loss of OC from the entire peat column. An uncertainty analysis also revealed that the magnitude and timing of soil OC loss from thawed forest peat depends substantially on variation in OC input rates to bog peat and variation in decay constants for shallow and deep OC stocks. These findings suggest that permafrost thaw and the subsequent release of OC from thawed peat will likely reduce the strength of northern permafrost-affected peatlands as a carbon dioxide sink, and consequently, will likely accelerate rates of atmospheric warming.

  16. Treatment of peat bogs harvested by deep digging technique. A lterature study; Efterbehandling av torvtaekter utbrutna med djupbrytningsteknik; En litteraturstudie

    Energy Technology Data Exchange (ETDEWEB)

    Hoernsten, L [Swedish Univ. of Agricultural Sciences, Umeaa (Sweden). Dept. of Forest Ecology

    1992-06-01

    The aim of this study is to describe how peat bogs harvested by deep digging technique can be treated after harvesting has come to an end. The study points out treatment methods, how the treatments are carried out and to indicate the most appropriate method of harvest for optimum results. Costs and benefits are calculated for the methods involving cultivation. The knowledge gained from traditional peat harvesting technique indicate forestry, energy wood production and establishment of ponds as possible alternatives. Energy grass cultivation and establishments of game parks have not been tested. but are assumed to be viable on suitable sites. Establishment of duck ponds are also possible, even though conditions for these are better on firm ground. In this study spruce is estimated to produce 200 cubic meters during 105 year whilst pine produces 300 cubic meters. Calculations for pine and spruce estimate costs of respectively 17000 and 18000 SEK per hectare after 105 years. Energy wood production is estimated to be 11.6 tons dry matter per hectare and year which gives a net cost of 19000 SEK per hectare. Similarly energy grass cultivation results in an average annual harvest of 6.5 ton dry matter and a cost of 59000 SEK per hectare. If the results are applied to three specific cases, then forest cultivation and establishment of ponds are possible in all cases. Neither energy wood nor energy grass are appropriate in any of the three regions. At the particular site for this study all methods mentioned are possible. Depending on whether draining leads to a high or low water table, the most appropriate course would be the establishment of a pond respectively a game park of forest cultivation. (59 refs., 12 tabs., 4 figs.).

  17. UAV based 3D digital surface model to estimate paleolandscape in high mountainous environment

    Science.gov (United States)

    Mészáros, János; Árvai, Mátyás; Kohán, Balázs; Deák, Márton; Nagy, Balázs

    2016-04-01

    Our method to present current state of a peat bog was focused on the possible use of a UAV-system and later Structure-from-motion algorithms as processing technique. The peat bog site is located on the Vinderel Plateau, Farcǎu Massif, Maramures Mountains (Romania). The peat bog (1530 m a.s.l., N47°54'11", E24°26'37") lies below Rugasu ridge (c. 1820 m a.s.l.) and the locality serves as a conservation area for fallen down coniferous trees. Peat deposits were formed in a landslide concavity on the western slope of Farcǎu Massif. Nowadays the site is surrounded by a completely deforested landscape, and Farcǎu Massif lies above the depressed treeline. The peat bog has an extraordinary geomorphological situation, because a gully reached the bog and drained the water. In the recent past sedimentological and dendrochronological researches have been initiated. However, an accurate 3D digital surface model also needed for a complex paleoenvironmental research. Last autumn the bog and its surroundings were finally surveyed by a multirotor UAV developed in-house based on an open-source flight management unit and its firmware. During this survey a lightweight action camera (mainly to decrease payload weight) was used to take aerial photographs. While our quadcopter is capable to fly automatically on a predefined flight route, several over- and sidelapping flight lines were generated prior to the actual survey on the ground using a control software running on a notebook. Despite those precautions, limited number of batteries and severe weather affected our final flights, resulting a reduced surveyed area around peat bog. Later, during the processing we looked for a reliable tool which powerful enough to process more than 500 photos taken during flights. After testing several software Agisoft PhotoScan was used to create 3D point cloud and mesh about bog and its environment. Due to large number of photographs PhotoScan had to be configured for network processing to get

  18. Morality, Moral Luck and Responsibility. Fortune's Web

    DEFF Research Database (Denmark)

    Nielsen, Carsten Fogh

    2011-01-01

    Anmeldelse af Nafsika Athanassoulis bog: Morality, Moral Lock and Responsibility (Palgrave MacMillian 2010)......Anmeldelse af Nafsika Athanassoulis bog: Morality, Moral Lock and Responsibility (Palgrave MacMillian 2010)...

  19. National Program for Inspection of Non-Federal Dams. Tihonet Pond Number 2 Dam (MA 00030), Massachusetts Coastal Basin, Wareham, Massachusetts. Phase I Inspection Report.

    Science.gov (United States)

    1981-07-01

    drainage area above the dam is 8.1 square miles. The watershed is characterized by irregular topography: cranberry bogs, small ponds and depressions ...and recreational purposes. Water from this pond is used in the U irrigation of cranberry bogs downstream. The maximum storage capacity of the dam is...295-1000 g. PURPOSE OF DAM The dam impounds Tihonet Pond which is a storage reservoir 4_- 4 4: . * used principally for irrigating cranberry bogs which

  20. Soil microbial community composition is correlated to soil carbon processing along a boreal wetland formation gradient

    Science.gov (United States)

    Chapman, Eric; Cadillo-Quiroz, Hinsby; Childers, Daniel L.; Turetsky, Merritt R.; Waldrop, Mark P.

    2017-01-01

    Climate change is modifying global biogeochemical cycles. Microbial communities play an integral role in soil biogeochemical cycles; knowledge about microbial composition helps provide a mechanistic understanding of these ecosystem-level phenomena. Next generation sequencing approaches were used to investigate changes in microbial functional groups during ecosystem development, in response to climate change, in northern boreal wetlands. A gradient of wetlands that developed following permafrost degradation was used to characterize changes in the soil microbial communities that mediate C cycling: a bog representing an “undisturbed” system with intact permafrost, and a younger bog and an older bog that formed following the disturbance of permafrost thaw. Reference 16S rRNA databases and several diversity indices were used to assess structural differences among these communities, to assess relationships between soil microbial community composition and various environmental variables including redox potential and pH. Rates of potential CO2 and CH4 gas production were quantified to correlate sequence data with gas flux. The abundance of organic C degraders was highest in the youngest bog, suggesting higher rates of microbial processes, including potential CH4 production. In addition, alpha diversity was also highest in the youngest bog, which seemed to be related to a more neutral pH and a lower redox potential. These results could potentially be driven by increased niche differentiation in anaerobic soils. These results suggest that ecosystem structure, which was largely driven by changes in edaphic and plant community characteristics between the “undisturbed” permafrost bog and the two bogs formed following permafrost thaw, strongly influenced microbial function.

  1. Norsk inspiration til uddannelse og job

    DEFF Research Database (Denmark)

    Skovhus, Randi Boelskifte; Thomsen, Rie; Buhl, Rita

    2017-01-01

    Anmeldelse af bog om det norske fag Utdanningsvalg - inspiration til arbejde med uddannelse og job......Anmeldelse af bog om det norske fag Utdanningsvalg - inspiration til arbejde med uddannelse og job...

  2. Comprehensive Structural Dynamic Analysis of the SSME/AT Fuel Pump First-Stage Turbine Blade

    Science.gov (United States)

    Brown, A. M.

    1998-01-01

    A detailed structural dynamic analysis of the Pratt & Whitney high-pressure fuel pump first-stage turbine blades has been performed to identify the cause of the tip cracking found in the turbomachinery in November 1997. The analysis was also used to help evaluate potential fixes for the problem. Many of the methods available in structural dynamics were applied, including modal displacement and stress analysis, frequency and transient response to tip loading from the first-stage Blade Outer Gas Seals (BOGS), fourier analysis, and shock spectra analysis of the transient response. The primary findings were that the BOGS tip loading is impulsive in nature, thereby exciting many modes of the blade that exhibit high stress at the tip cracking location. Therefore, a proposed BOGS count change would not help the situation because a clearly identifiable resonance situation does not exist. The recommendations for the resolution of the problem are to maintain the existing BOGS count, eliminate the stress concentration in the blade due to its geometric design, and reduce the applied load on the blade by adding shiplaps in the BOGS.

  3. Ivar Andenæs: Medier i sjokk og sorg. Pressens møde med terroren 22. juli 2011

    DEFF Research Database (Denmark)

    Andersen, Michael Bruun

    2013-01-01

    Anmeldelse af bog om norske journalisters vurdering af norske mediers dækning af Breivik-massakren.......Anmeldelse af bog om norske journalisters vurdering af norske mediers dækning af Breivik-massakren....

  4. UAV Remote Sensing Can Reveal the Effects of Low-Impact Seismic Lines on Surface Morphology, Hydrology, and Methane (CH4) Release in a Boreal Treed Bog

    Science.gov (United States)

    Lovitt, J.; Rahman, M. M.; Saraswati, S.; McDermid, G. J.; Strack, M.; Xu, B.

    2018-03-01

    Peatlands are globally significant stores of soil carbon, where local methane (CH4) emissions are strongly linked to water table position and microtopography. Historically, these factors have been difficult to measure in the field, constraining our capacity to observe local patterns of variability. In this paper, we show how remote sensing surveys conducted from unmanned aerial vehicle (UAV) platforms can be used to map microtopography and depth to water over large areas with good accuracy, paving the way for spatially explicit estimates of CH4 emissions. This approach enabled us to observe—for the first time—the effects of low-impact seismic lines (LIS; petroleum exploration corridors) on surface morphology and CH4 emissions in a treed-bog ecosystem in northern Alberta, Canada. Through compaction, LIS lines were found to flatten the observed range in microtopographic elevation by 46 cm and decrease mean depth to water by 15.4 cm, compared to surrounding undisturbed conditions. These alterations are projected to increase CH4 emissions by 20-120% relative to undisturbed areas in our study area, which translates to a total rise of 0.011-0.027 kg CH4 day-1 per linear kilometer of LIS ( 2 m wide). The 16 km of LIS present at our 61 ha study site were predicted to boost CH4 emissions by 20-70 kg between May and September 2016.

  5. Comparison of Atmospheric Travel Distances of Several PAHs Calculated by Two Fate and Transport Models (The Tool and ELPOS with Experimental Values Derived from a Peat Bog Transect

    Directory of Open Access Journals (Sweden)

    Sabine Thuens

    2014-05-01

    Full Text Available Multimedia fate and transport models are used to evaluate the long range transport potential (LRTP of organic pollutants, often by calculating their characteristic travel distance (CTD. We calculated the CTD of several polycyclic aromatic hydrocarbons (PAHs and metals using two models: the OECD POV& LRTP Screening Tool (The Tool, and ELPOS. The absolute CTDs of PAHs estimated with the two models agree reasonably well for predominantly particle-bound congeners, while discrepancies are observed for more volatile congeners. We test the performance of the models by comparing the relative ranking of CTDs with the one of experimentally determined travel distances (ETDs. ETDs were estimated from historical deposition rates of pollutants to peat bogs in Eastern Canada. CTDs and ETDs of PAHs indicate a low LRTP. To eliminate the high influence on specific model assumptions and to emphasize the difference between the travel distances of single PAHs, ETDs and CTDs were analyzed relative to the travel distances of particle-bound compounds. The ETDs determined for PAHs, Cu, and Zn ranged from 173 to 321 km with relative uncertainties between 26% and 46%. The ETDs of two metals were shorter than those of the PAHs. For particle-bound PAHs the relative ETDs and CTDs were similar, while they differed for Chrysene.

  6. Convergent development of anodic bacterial communities in microbial fuel cells.

    KAUST Repository

    Yates, Matthew D; Kiely, Patrick D; Call, Douglas F; Rismani-Yazdi, Hamid; Bibby, Kyle; Peccia, Jordan; Regan, John M; Logan, Bruce E

    2012-01-01

    inocula: a wastewater treatment plant sample known to produce consistent power densities, a second wastewater treatment plant sample, and an anaerobic bog sediment. The bog-inoculated MFCs initially produced higher power densities than the wastewater

  7. Kant's Theory of virtue

    DEFF Research Database (Denmark)

    Nielsen, Carsten Fogh

    2012-01-01

    Anmeldelse af Anne Margaret Baxleys bog: "Kant's Thery of Virtue. The Value of Autocracy" (Cambridge University Press, 2010)......Anmeldelse af Anne Margaret Baxleys bog: "Kant's Thery of Virtue. The Value of Autocracy" (Cambridge University Press, 2010)...

  8. Geophysical characterization of peatlands using crosshole GPR full-waveform inversion: Case study from a bog in northwestern Germany

    Science.gov (United States)

    Schmäck, J.; Klotzsche, A.; Van Der Kruk, J.; Vereecken, H.; Bechtold, M.

    2017-12-01

    The characterization of peatlands is of particular interest, since areas with peat soils represent global hotspots for the exchange of greenhouse gases. Their effect on global warming depends on several parameters, like mean annual water level and land use. Models of greenhouse gas emissions and carbon accumulation in peatlands can be improved by including small-scale soil properties that e.g. act as gas traps and periodically release gases to the atmosphere during ebullition events. Ground penetrating radar (GPR) is well suited to non- or minimal invasively characterize and improve our understanding of dynamic processes that take place in the critical zone. It uses high frequency electromagnetic waves to image and characterize the dielectric permittivity and electrical conductivity of the critical zone, which can be related to hydrogeological properties like porosity, soil water content, salinity and clay content. In the last decade, the full-waveform inversion of crosshole GPR data has proved to be a powerful tool to improve the image resolution compared to standard ray-based methods. This approach was successfully applied to several different aquifers and was able to provide decimeter-scale resolution images including small-scale high contrast layers that can be related to zones of high porosity, zones of preferential flow or clay lenses. The comparison to independently measured e.g. logging data proved the reliability of the method. Here, for the first time crosshole GPR full-waveform inversion is used to image three peatland plots with different land use that are part of the "Ahlen-Falkenberger Moor peat bog complex" in northwestern Germany. The full-waveform inversion of the acquired data returned higher resolution images than standard ray-based GPR methods, and, is able to improve our understanding of subsurface structures. The comparison of the different plots is expected to provide new insights into gas content and gas trapping structures across different

  9. Experimental Whole-Ecosystem Warming Alters Vegetation Phenology in a Boreal Spruce Bog: Initial Results from the SPRUCE Experiment

    Science.gov (United States)

    Richardson, A. D.

    2016-12-01

    Phenology is one of the most robust indicators of the biological impacts of global change. However, the response of phenology to future environmental conditions still remains highly uncertain because of the challenges associated with conducting realistic manipulative experiments. At the SPRUCE (Spruce and Peatland Responses Under Climatic and Environmental Change) experiment in the north-central United States, experimental temperature (0 to +9°C above ambient) and CO2 (ambient and elevated) treatments are being applied to mature, and intact, Picea mariana-Sphagnum spp. bog communities in their native habitat through the use of ten large (approximately 12 m wide, 10 m high) open-topped enclosures. We are tracking vegetation green-up and senescence in these chambers using repeat digital photography. Within each chamber, images are recorded every 30 minutes and uploaded to PhenoCam (http://phenocam.sr.unh.edu), where processed to yield quantitative measures of canopy color. These data are complemented by on-the-ground phenological data collected by human observers. Air warming treatments at SPRUCE began in August 2015. We observed a delay in senescence during autumn 2015 (2-5 days per degree of warming) and an advance in onset during spring 2016 (1-4 days per degree of warming). These patterns are robust across species and methods of phenological observation (i.e. camera-based vs. human observer). And, our results show very little evidence for photoperiod acting as a constraint on the response to warming. Early spring onset and consequent loss of frost hardiness in the warmest chambers proved disadvantageous when a brief period of extreme cold (to -12°C in the control chambers, to -3°C in the +9°C chambers) followed a month of generally mild weather. Foliage mortality for both Larix and Picea was immediate and severe, although both species subsequently re-flushed. These results give support for the hypothesis that warming may enhance the likelihood of spring frost

  10. Silver flowe, Galloway, Scotland

    Energy Technology Data Exchange (ETDEWEB)

    Ratcliffe, D A; Walker, D

    1958-01-01

    The silver flowe consists of a series of blanket bogs differentiated by physiography and at one end of the series showing marked affinities with raised bog. The definitive vegetation type of each individual bog is a sphagnum-dominated pool and hummock complex. The pool and hummock complex is described in terms of a small-scale succession involving several recognizable stages. To facilitate quantitative description, the pool and hummock complex is divided into four vertical levels (pool, flat, medium hummock and tall hummock) and different micro-communities are recognized within each one. The floristic composition of these units was analysed by the selective placing of a 1 m. quadrat. The pattern of pool and hummock complex is complicated by different developmental trends, often involving erosion. A method was devised to measure quantitatively the relationship between the vertical distribution of plant species and water level. The stratigraphy of two bogs of the series is described and shows (a) that the two patches are more closely akin to blanket bog than to raised bogs; (b) that there has been a relatively recent change-over from a sphagnum-molinia community to the present pool and hummock complex. The pool and hummock system is not regarded as a 'regeneration complex' but the validity of considering the various stages as part of a small-scale succession is discussed. Three possible future developments of this community are investigated: (1) persistence of pool and hummock complex, with a very high water table, (2) development of intermediate bog, with a rather lower water table and (3) degeneration of pool and hummock complex, with a rapid and considerable lowering of the water table. The alignment of pools with their long axes at right angles to the slope is discussed.

  11. Greenhouse effects of the peat production and use as compared to coal, oil, natural gas and wood

    International Nuclear Information System (INIS)

    Hillebrand, K.; Wihersaari, M.

    1993-01-01

    This report examines the greenhouse effects of greenhouse gas emissions (carbon dioxide, methane and nitrous oxide) arising from certain production and utilization chains of peat and compares them with the corresponding effects associated with the production and utilization chains of coal, oil, natural gas and wood. In order to estimate the greenhouse effects of the peat production and utilization chains, the initial state of the peat bog together with the instantaneous and cumulative greenhouse effects associated with the production and burning of peat as well as subsequent use of the production area were taken into account. The initial state of the peat bog was taken to be either a bog in its natural sale, a forest-drained bog or a cultivated peatland. As regards alternatives for subsequent use of the peat production area, afforestation, paludification and lake formation were all examined

  12. The Effects of Peatland Plant Functional Types and Altered Hydrology on Porewater Chemistry in a Northern Bog

    Science.gov (United States)

    Daniels, A.; Kane, E. S.; Lilleskov, E. A.; Kolka, R. K.; Chimner, R. A.; Potvin, L. R.; Romanowicz, K. J.

    2012-12-01

    Northern wetlands, peatlands in particular, have been shown to store around 30% of the world's soil carbon and thus play a significant role in the carbon cycle of our planet. Carbon accumulation in peatlands is the result of retarded decomposition due to low oxygen availability in these water-logged environments. Changes in our planet's climate cycles are altering peatland hydrology and vegetation communities, resulting in changes in their ability to sequester carbon through increases in peat carbon oxidation and mineralization. To date, the consequences of altered hydrology and changes in vegetation communities, and their interactive effects on carbon storage, are not well understood. We have initiated a research plan that assesses the varying roles that water table variation and vegetation communities have on extracellular enzyme activity and labile carbon availability in porewater from an ombrotrophic bog. We assessed the effects of plant functional group (ericaceous shrubs, sedges, and bryophytes) and water table position on biogeochemical processes. Specifically, we measured dissolved organic carbon (DOC), total dissolved nitrogen (TDN), enzyme activity, organic acids, anions and cations, spectral indexes of aromaticity, and phenolic content in addressing our hypotheses of responses to climate change drivers. Research on these components will evaluate the relative importance of biology, water table, and their interactive affects on the porewater quality of peatlands. We hypothesized that oxygen availability will strongly influence decomposition in these systems but that this response will largely be mediated by changes in plant community and the enzymes associated with root exudates and mycorrhizae. To date, our data confirm vegetation and water table related patterns. Acetate and propionate concentrations in the sedge-dominated communities dropped significantly with depth and drainage, relative to the control and ericaceous treatments, which likely reflects

  13. 75 FR 35095 - Excepted Service

    Science.gov (United States)

    2010-06-21

    ... Agriculture DAGS60603 Special Assistant for Marketing and Regulatory Programs. Effective May 7, 2010... Executive Associate Director. Effective May 4, 2010. BOGS10018 Confidential Assistant to the Associate Director for General Government Programs. Effective May 7, 2010. BOGS10019 Confidential Assistant to the...

  14. Hitler og Stalin arm i arm

    DEFF Research Database (Denmark)

    Bryld, Claus

    2015-01-01

    Levende fortalt bog om pagten mellem Hitler og Stalin, som udløste krigen og kastede lange skygger over Europas historie.......Levende fortalt bog om pagten mellem Hitler og Stalin, som udløste krigen og kastede lange skygger over Europas historie....

  15. Ecosystem Model Performance at Wetlands: Results from the North American Carbon Program Site Synthesis

    Science.gov (United States)

    Sulman, B. N.; Desai, A. R.; Schroeder, N. M.; NACP Site Synthesis Participants

    2011-12-01

    Northern peatlands contain a significant fraction of the global carbon pool, and their responses to hydrological change are likely to be important factors in future carbon cycle-climate feedbacks. Global-scale carbon cycle modeling studies typically use general ecosystem models with coarse spatial resolution, often without peatland-specific processes. Here, seven ecosystem models were used to simulate CO2 fluxes at three field sites in Canada and the northern United States, including two nutrient-rich fens and one nutrient-poor, sphagnum-dominated bog, from 2002-2006. Flux residuals (simulated - observed) were positively correlated with measured water table for both gross ecosystem productivity (GEP) and ecosystem respiration (ER) at the two fen sites for all models, and were positively correlated with water table at the bog site for the majority of models. Modeled diurnal cycles at fen sites agreed well with eddy covariance measurements overall. Eddy covariance GEP and ER were higher during dry periods than during wet periods, while model results predicted either the opposite relationship or no significant difference. At the bog site, eddy covariance GEP had no significant dependence on water table, while models predicted higher GEP during wet periods. All models significantly over-estimated GEP at the bog site, and all but one over-estimated ER at the bog site. Carbon cycle models in peatland-rich regions could be improved by incorporating better models or measurements of hydrology and by inhibiting GEP and ER rates under saturated conditions. Bogs and fens likely require distinct treatments in ecosystem models due to differences in nutrients, peat properties, and plant communities.

  16. Bag pigtråd

    DEFF Research Database (Denmark)

    Bjerre, Jacob Halvas

    2015-01-01

    BogFeature om Inger Bjørn Knudsen: Bag Pigtråd - Rom flygtningelejr 1945-1948. Udg. af Lemvig Museum, 2014. 80 sider......BogFeature om Inger Bjørn Knudsen: Bag Pigtråd - Rom flygtningelejr 1945-1948. Udg. af Lemvig Museum, 2014. 80 sider...

  17. Evaluation of mitigation for acid aluminum leachate from a highway fill in Garrett County, Maryland. Research report (Final)

    International Nuclear Information System (INIS)

    Gracie, J.W.

    1992-01-01

    The effectiveness of a man-made sphagnum bog in reducing acidity and removing aluminum from an acidic leachate is evaluated. Although some effectiveness is demonstrated, the bog does not retain its ability to function as a result of physical changes due to uncontrolled sediment deposition in it

  18. 700 kg jern med de smukkeste krystaller

    DEFF Research Database (Denmark)

    Pedersen, Jens Olaf Pepke

    2017-01-01

    Anmeldelse af Holger Pedersen, “Pallas Iron – Russia’s first meteorite”, 260 sider, 190 kr. BoD 2017 (www.bod.dk/bog/).......Anmeldelse af Holger Pedersen, “Pallas Iron – Russia’s first meteorite”, 260 sider, 190 kr. BoD 2017 (www.bod.dk/bog/)....

  19. Thermoeconomic optimization of a cryogenic refrigeration cycle for re-liquefaction of the LNG boil-off gas

    Energy Technology Data Exchange (ETDEWEB)

    Sayyaadi, Hoseyn; Babaelahi, M. [Faculty of Mechanical Engineering-Energy Division, K.N. Toosi University of Technology, P.O. Box: 19395-1999, No. 15-19, Pardis Str., Mollasadra Ave., Vanak Sq., Tehran 1999 143344 (Iran)

    2010-09-15

    The development of the liquefaction process for the Liquefied Natural Gas (LNG) boil-off re-liquefaction plants will be addressed to provide an environmentally friendly and cost effective solution for the gas transportation. In this manner, onboard boil-off gas (BOG) re-liquefaction system as a cryogenic refrigeration cycle is utilized in order to re-liquefy the BOG and returns it to the cargo tanks instead of burning it. In this paper, a thermoeconomic optimization of the LNG-BOG liquefaction system is performed. A thermoeconomic model based on energy and exergy analyses and an economic model according to the total revenue requirement (TRR) are developed. Minimizing of the unit cost of the refrigeration effect as a product of BOG re-liquefaction plant is performed using the genetic algorithm. Results of thermoeconomic optimization are compared with corresponding features of the base case system. Finally, sensitivity of the total cost of the system product with respect to the variation of some operating parameters is studied. (author)

  20. Fimbriiglobus ruber gen. nov., sp. nov., a Gemmata-like planctomycete from Sphagnum peat bog and the proposal of Gemmataceae fam. nov.

    Science.gov (United States)

    Kulichevskaya, Irina S; Ivanova, Anastasia A; Baulina, Olga I; Rijpstra, W Irene C; Sinninghe Damsté, Jaap S; Dedysh, Svetlana N

    2017-02-01

    An aerobic, budding, dark pink to red-pigmented bacterium was isolated from an acidic boreal Sphagnum peat bog and designated strain SP5T. Cells of this strain were non-motile spheres that were uniformly covered with crateriform pits and fimbria, and tended to form aggregates during growth in liquid media. Strain SP5T was capable of growth between pH 4.0 and pH 6.8 (optimum at pH 5.5-6.0) and at temperatures between 10 and 30 °C (optimum at 20-25 °C). The preferred growth substrates were sugars and some heteropolysaccharides. The major fatty acids were C20 : 1ω9c, C16 : 1ω9c and C16 : 0, and the major polar lipid was trimethylornithine. Cells contained also significant amounts of bound (ω-1)OH-C30 : 1 fatty acid. The quinone was menaquinone-6, and the G+C content of the DNA was 60.7 mol%. Strain SP5T was a member of the order Planctomycetales and belonged to the phylogenetic lineage defined by the genus Gemmata. It displayed 88 and 89 % 16S rRNA gene sequence similarity to Gemmata obscuriglobusUQM 2246T and 'Gemmata massiliana' IIL30, 89 % to Zavarzinella formosa A10T and 86 % to Telmatocola sphagniphila SP2T. However, strain SP5T differed from members of these genera by cell morphology, substrate utilization pattern and fatty acid composition. Based on these data, the novel isolate should be considered as representing a novel species of a new genus of planctomycetes, for which the name Fimbriiglobus ruber gen. nov., sp. nov, is proposed. The type strain is SP5T (=LMG 29572T=VKM B-3045T). We also suggest the establishment of a novel family, Gemmataceaefam. nov., which includes the phylogenetically related genera Gemmata, Zavarzinella, Telmatocola and Fimbriiglobus.

  1. Forord til den danske udgave af bogen rådgivning og terapi med børn

    DEFF Research Database (Denmark)

    Kragh-Müller, Grethe

    2007-01-01

    En bog om rådgivning og terapi med børn med en integrativ indfaldsvinkel. Der tages udgangspunkt i forskellige teorier og metoder.......En bog om rådgivning og terapi med børn med en integrativ indfaldsvinkel. Der tages udgangspunkt i forskellige teorier og metoder....

  2. The effect of temperature on growth and competition between Sphagnum species

    NARCIS (Netherlands)

    Breeuwer, A.J.G.; Heijmans, M.M.P.D.; Robroek, B.J.M.; Berendse, F.

    2008-01-01

    Peat bogs play a large role in the global sequestration of C, and are often dominated by different Sphagnum species. Therefore, it is crucial to understand how Sphagnum vegetation in peat bogs will respond to global warming. We performed a greenhouse experiment to study the effect of four

  3. Decomposition of Carex and Sphagnum litter in two mesotrophic fens differing in dominant plant species

    NARCIS (Netherlands)

    Scheffer, R.A.; Van Logtestijn, R. S P; Verhoeven, J. T A

    2001-01-01

    Peatlands can be classified into fens and bogs based on their hydrology. Development of fens to bogs is accompanied by the invasion of Sphagnum species. The purpose of this study was to determine how the decomposition process in fens is influenced by the transition from a vascular plant-dominated

  4. Effects of permafrost aggradation on peat properties as determined from a pan-Arctic synthesis of plant macrofossils

    Science.gov (United States)

    Treat, C.C.; Jones, Miriam C.; Camill, P.; Gallego-Sala, A.; Garneau, M.; Harden, Jennifer W.; Hugelius, G.; Klein, E.S.; Kokfelt, U.; Kuhry, P.; Loisel, Julie; Mathijssen, J.H.; O'Donnell, J.A.; Oksanen, P.O.; Ronkainen, T.M.; Sannel, A.B.K.; Talbot, J. J.; Tarnocal, C.M.; Valiranta, M.

    2016-01-01

    Permafrost dynamics play an important role in high-latitude peatland carbon balance and are key to understanding the future response of soil carbon stocks. Permafrost aggradation can control the magnitude of the carbon feedback in peatlands through effects on peat properties. We compiled peatland plant macrofossil records for the northern permafrost zone (515 cores from 280 sites) and classified samples by vegetation type and environmental class (fen, bog, tundra and boreal permafrost, and thawed permafrost). We examined differences in peat properties (bulk density, carbon (C), nitrogen (N) and organic matter content, and C/N ratio) and C accumulation rates among vegetation types and environmental classes. Consequences of permafrost aggradation differed between boreal and tundra biomes, including differences in vegetation composition, C/N ratios, and N content. The vegetation composition of tundra permafrost peatlands was similar to permafrost-free fens, while boreal permafrost peatlands more closely resembled permafrost-free bogs. Nitrogen content in boreal permafrost and thawed permafrost peatlands was significantly lower than in permafrost-free bogs despite similar vegetation types (0.9% versus 1.5% N). Median long-term C accumulation rates were higher in fens (23 g C m−2 yr−1) than in permafrost-free bogs (18 g C m−2 yr−1) and were lowest in boreal permafrost peatlands (14 g C m−2 yr−1). The plant macrofossil record demonstrated transitions from fens to bogs to permafrost peatlands, bogs to fens, permafrost aggradation within fens, and permafrost thaw and reaggradation. Using data synthesis, we have identified predominant peatland successional pathways, changes in vegetation type, peat properties, and C accumulation rates associated with permafrost aggradation.

  5. Politisk marketing

    DEFF Research Database (Denmark)

    Disciplinen politisk marketing er udbredt i mange vestlige lande. Imidlertid er kendskabet til politisk marketing i Danmark bemærkelsesværdigt lavt. I det lys er denne bog Politisk Marketing: Personer, Partier & Praksis den første bog i Danmark, som -ud fra marketing- indkredser de sidste mange års...... brudflader i dansk politik. Gennem ti bidrag fra forskere og praktikere udskraber forfatterne et DNA for feltet politisk marketing. Kort sagt kan du i denne bog finde svarene på: Hvad er politisk marketing? Hvordan har det udviklet sig? Og hvilke konsekvenser har dette fænomen for vælgere, partier og...

  6. Evaluation of ecological constraints on peat mining in New Brunswick

    Energy Technology Data Exchange (ETDEWEB)

    Gautreau-Daigle, H

    1990-07-01

    A study was undertaken to obtain baseline information on moose and waterfowl usage of peatlands in the Escuminac bog complex in New Brunswick, in order to determine the impact of existing peat mining activities and to assist in making decisions regarding future resource development. The bog complex comprises a relatively large number of freshwater ponds which support breeding populations for waterfowl and serve as staging areas during bird migrations. Aerial surveys were carried out to quantify the use of these ponds by waterfowl and to determine changes in their level of use as a result of peat extraction. Results indicate that usage of ponds by birds seems mostly limited to staging and migration, except for black and ring-necked ducks. Those species are the most significant users of bog ponds and have been found to breed and raise young in the ponds. Some areas were found to get more waterfowl than others, but this was not shown to be related to peat mining activity. Active mined areas were devoid of waterfowl, but this area was a relatively small portion of the total bog area. The moose survey examined moose activity in a control area (without peat mining) and a representative bog area where peat mining occurred. Results do not indicate a difference in the moose activity patterns between the two areas. 9 refs., 25 figs., 17 tabs.

  7. Response of Sphagnum species mixtures to increased temperature and nitrogen availability

    NARCIS (Netherlands)

    Breeuwer, A.J.G.; Heijmans, M.M.P.D.; Berendse, F.; Gleichman, J.M.; Robroek, B.J.M.; Limpens, J.

    2009-01-01

    To predict the role of ombrotrophic bogs as carbon sinks in the future, it is crucial to understand how Sphagnum vegetation in bogs will respond to global change. We performed a greenhouse experiment to study the effects of two temperature treatments (17.5 and 21.7°C) and two N addition treatments

  8. Ambiguous chair

    DEFF Research Database (Denmark)

    Manelius, Anne-Mette

    2011-01-01

    Bidrag til gør-det-selv bog, hvor det beskrives i udførlige tegninger, hvordan man bygger sin egen 'Ambiguous Chair', en tekstilforskallet stol.......Bidrag til gør-det-selv bog, hvor det beskrives i udførlige tegninger, hvordan man bygger sin egen 'Ambiguous Chair', en tekstilforskallet stol....

  9. Diagnosis of bacterial overgrowth of the small intestine. Comparison of the 14C-D-xylose breath test and jejunal cultures in 60 patients

    DEFF Research Database (Denmark)

    Rumessen, J J; Gudmand-Høyer, E; Bachmann, E

    1985-01-01

    the presence of BOG was ruled out (diagnoses: irritable bowel syndrome, 8; chronic diarrhoea, 6; and lactose malabsorption, 1). These patients were used as controls. The other 22 of the 60 patients could not be placed in either group owing to the presence of factors known to predispose for BOG; none of them...

  10. THE ROLE OF THE LANDSLIDE LAKES (WETLANDS IN TRANSFORMATION OF PHYSICOCHEMICAL WATER ON THE EXAMPLE VELKE OSTURNIANSKE JAZERO, SLOVAKIA

    Directory of Open Access Journals (Sweden)

    Tadeusz Molenda

    2015-03-01

    Full Text Available In the article a role of the flow bog in the transformation of the physical-chemical properties of waters was described. They demonstrated that in the water flowing out of the bog a fall in the mineralization and concentrations of selected ions take place towards feedwaters. The species stated within the bog of plants, mainly Carex rostrata, Schoenoplectus lacustris, Equisetum fluviatile, Juncus effusus, Menyanthes trifoliata can be found the under construction application of sewage treatment plant on highlands of the Western Carpathians (to 900 m.n.p.m., the average annual air temperature > of 5 °C and the time of lying of the snowy lid of 90 days in the year.

  11. Evapotranspiration from two peatland watersheds

    Science.gov (United States)

    Roger R. Bay

    1968-01-01

    Measurements of precipitation, runoff, and bog water table levels have provided data for the calculation of evapotranspiration from two forested peatland watersheds near Grand Rapids, Minnesota (ca. 47? 32'N, 93? 28'W). Continuous hydrologie records were collected on one experimental bog for 6 years (1961-1966) and on the other for the past 2 years (1965-1966...

  12. Den levende sangfugl

    DEFF Research Database (Denmark)

    Bjerre, Thomas Ærvold

    2009-01-01

    Kronik om Harper Lee's roman "Dræb ikke en sangfugl" (1960) og den store indflydelse bog og film har haft på amerikansk kultur. Udgivelsesdato: 30. juli......Kronik om Harper Lee's roman "Dræb ikke en sangfugl" (1960) og den store indflydelse bog og film har haft på amerikansk kultur. Udgivelsesdato: 30. juli...

  13. Hydrologic controls on DOC, As and Pb export from a polluted peatland - the importance of heavy rain events, antecedent moisture conditions and hydrological connectivity

    Science.gov (United States)

    Broder, T.; Biester, H.

    2015-08-01

    Bogs can store large amounts of lead (Pb) and arsenic (As) from atmospheric deposition of anthropogenic emissions. Pb and As are exported along with dissolved organic carbon (DOC) from these organic-rich systems, but it is not yet clear which hydrological (pre)conditions favor their export. This study combines a 1-year monitoring of precipitation, bog water level and pore water concentration changes with bog discharge and DOC, iron, As and Pb stream concentrations. From these data, annual DOC, As, and Pb exports were calculated. Concentrations ranged from 5 to 30 mg L-1 for DOC, 0.2 to 1.9 μg L-1 for As, and 1.3 to 12 μg L-1 for Pb, with highest concentrations in late summer. As and Pb concentrations significantly correlated with DOC concentrations. Fluxes depended strongly on discharge, as 40 % of As and 43 % of Pb were exported during 10 % of the time with the highest discharge, pointing out the over-proportional contribution of short-time, high-discharge events to annual As, Pb and DOC export. Exponential increase in element export from the bog is explained by connection of additional DOC, As and Pb pools in the acrotelm during water table rise, which is most pronounced after drought. Pb, As and DOC concentrations in pore water provide evidence of an increase in the soluble Pb pool as soon as the peat layer becomes hydrologically connected, while DOC and As peak concentrations in runoff lag behind in comparison to Pb. Our data indicate a distinct bog-specific discharge threshold of 8 L s-1, which is thought to depend mainly on the bogs size and drainage conditions. Above this threshold, element concentrations do not further increase and discharge becomes diluted. Combining pore water and discharge data shows that As and Pb exports are dependent on not only the amount of precipitation and discharge but also on the frequency and depth of water table fluctuations. Comparing the annual bog As and Pb export with element inventories indicates that As is much more

  14. Active methanotrophs in two contrasting North American peatland ecosystems revealed using DNA-SIP.

    Science.gov (United States)

    Gupta, Varun; Smemo, Kurt A; Yavitt, Joseph B; Basiliko, Nathan

    2012-02-01

    The active methanotroph community was investigated in two contrasting North American peatlands, a nutrient-rich sedge fen and nutrient-poor Sphagnum bog using in vitro incubations and (13)C-DNA stable-isotope probing (SIP) to measure methane (CH(4)) oxidation rates and label active microbes followed by fingerprinting and sequencing of bacterial and archaeal 16S rDNA and methane monooxygenase (pmoA and mmoX) genes. Rates of CH(4) oxidation were slightly, but significantly, faster in the bog and methanotrophs belonged to the class Alphaproteobacteria and were similar to other methanotrophs of the genera Methylocystis, Methylosinus, and Methylocapsa or Methylocella detected in, or isolated from, European bogs. The fen had a greater phylogenetic diversity of organisms that had assimilated (13)C, including methanotrophs from both the Alpha- and Gammaproteobacteria classes and other potentially non-methanotrophic organisms that were similar to bacteria detected in a UK and Finnish fen. Based on similarities between bacteria in our sites and those in Europe, including Russia, we conclude that site physicochemical characteristics rather than biogeography controlled the phylogenetic diversity of active methanotrophs and that differences in phylogenetic diversity between the bog and fen did not relate to measured CH(4) oxidation rates. A single crenarchaeon in the bog site appeared to be assimilating (13)C in 16S rDNA; however, its phylogenetic similarity to other CO(2)-utilizing archaea probably indicates that this organism is not directly involved in CH(4) oxidation in peat.

  15. Lateral expansion and carbon exchange of a boreal peatland in Finland resulting in 7000 years of positive radiative forcing

    Science.gov (United States)

    Mathijssen, Paul J. H.; Kähkölä, Noora; Tuovinen, Juha-Pekka; Lohila, Annalea; Minkkinen, Kari; Laurila, Tuomas; Väliranta, Minna

    2017-03-01

    Data on past peatland growth patterns, vegetation development, and carbon (C) dynamics during the various Holocene climate phases may help us to understand possible future climate-peatland feedback mechanisms. In this study, we analyzed and radiocarbon dated several peat cores from Kalevansuo, a drained bog in southern Finland. We investigated peatland succession and C dynamics throughout the Holocene. These data were used to reconstruct the long-term atmospheric radiative forcing, i.e., climate impact of the peatland since initiation. Kalevansuo peat records revealed a general development from fen to bog, typical for the southern boreal zone, but the timing of ombrotrophication varied in different parts of the peatland. Peat accumulation patterns and lateral expansion through paludification were influenced by fires and climate conditions. Long-term C accumulation rates were overall lower than the average values found from literature. We suggest the low accumulation rates are due to repeated burning of the peat surface. Drainage for forestry resulted in a nearly complete replacement of typical bog mosses by forest species within 40 years after drainage. The radiative forcing reconstruction suggested positive values (warming) for the first 7000 years following initiation. The change from positive to negative forcing was triggered by an expansion of bog vegetation cover and later by drainage. The strong relationship between peatland area and peat type with radiative forcing suggests a possible feedback for future changing climate, as high-latitude peatlands may experience prominent regime shifts, such as fen to bog transitions.

  16. En verden uden ende

    DEFF Research Database (Denmark)

    Pedersen, Jens Olaf Pepke

    2017-01-01

    Multivers. Er der kun ét, eller er der utallige universer med hver sine naturlove? Det er emnet for en nyoversat bog af fysikeren Stephen Hawking og forfatteren Leonard Mlodinow.......Multivers. Er der kun ét, eller er der utallige universer med hver sine naturlove? Det er emnet for en nyoversat bog af fysikeren Stephen Hawking og forfatteren Leonard Mlodinow....

  17. Science og gode læringsmiljøer

    DEFF Research Database (Denmark)

    Broström, Stig; Frøkjær, Thorleif

    2018-01-01

    Science bliver ret sikkert en del af de nye, styrkede pædagogiske læreplaner. Her introducerer forfatterne begrebet, med eksempler, og med henvisninger til deres bog om samme emne......Science bliver ret sikkert en del af de nye, styrkede pædagogiske læreplaner. Her introducerer forfatterne begrebet, med eksempler, og med henvisninger til deres bog om samme emne...

  18. Dynamic vertical profiles of peat porewater chemistry in a northern peatland

    Science.gov (United States)

    Natalie A. Griffiths; Stephen D. Sebestyen

    2016-01-01

    We measured pH, cations, nutrients, and total organic carbon (TOC) over 3 years to examine weekly to monthly variability in porewater chemistry depth profiles (0–3.0 m) in an ombrotrophic bog in Minnesota, USA. We also compared temporal variation at one location to spatial variation in depth profiles at 16 locations across the bog. Most solutes exhibited large...

  19. Methylocella palustris gen. nov., sp. nov., a new methane-oxidizing acidophilic bacterium from peat bogs, representing a novel subtype of serine-pathway methanotrophs.

    Science.gov (United States)

    Dedysh, S N; Liesack, W; Khmelenina, V N; Suzina, N E; Trotsenko, Y A; Semrau, J D; Bares, A M; Panikov, N S; Tiedje, J M

    2000-05-01

    A new genus, Methylocella, and a new species, Methylocella palustris, are proposed for three strains of methane-oxidizing bacteria isolated from acidic Sphagnum peat bogs. These bacteria are aerobic, Gram-negative, colourless, non-motile, straight and curved rods that utilize the serine pathway for carbon assimilation, multiply by normal cell division and contain intracellular poly-beta-hydroxybutyrate granules (one at each pole). These strains use methane and methanol as sole sources of carbon and energy and are moderately acidophilic organisms with growth between pH 4.5 and pH 7.0, the optimum being at pH 5.0-5.5. The temperature range for growth is 10-28 degrees C with the optimum at 15-20 degrees C. The intracytoplasmic membrane system is different from those of type I and II methanotrophs. Cells contain an extensive periplasmic space and a vesicular membrane system connected to the cytoplasmic membrane. The strains grew only on media with a low salt content (0.2-0.5 g l(-1)). All three strains were found to possess soluble methane monooxygenase and are able to fix atmospheric nitrogen via an oxygen-sensitive nitrogenase. No products were observed in a PCR with particulate methane monooxygenase-targeted primers; hybridization with a pmoA probe was also negative. The major phospholipid fatty acids are 18:1 acids. The G+C content of the DNA is 61.2 mol%. The three strains share identical 16S rRNA gene sequences and represent a novel lineage of methane-oxidizing bacteria within the alpha-subclass of the class Proteobacteria and are only moderately related to type II methanotrophs of the Methylocystis-Methylosinus group. The three strains are most closely related to the acidophilic heterotrophic bacterium Beijerinckia indica subsp. indica (96.5% 16S rDNA sequence similarity). Collectively, these strains comprise a new species and genus Methylocella palustris gen. nov., sp. nov.; strain KT (= ATCC 700799T) is the type strain.

  20. Estimating exposure of piscivorous birds and sport fish to mercury in California lakes using prey fish monitoring: a predictive tool for managers

    Science.gov (United States)

    Ackerman, Joshua T.; Hartman, C. Alex; Eagles-Smith, Collin A.; Herzog, Mark P.; Davison, Jay; Ichikawa, Gary; Bonnema, Autumn

    2015-01-01

    Numerous water bodies in California are listed under the Clean Water Act as being impaired due to mercury (Hg) contamination. The Surface Water Ambient Monitoring Program (SWAMP), via the Bioaccumulation Oversight Group (BOG), has recently completed statewide surveys of contaminants in sport fish tissue from more than 250 lakes and rivers in California and throughout coastal waters. This effort focused on human health issues but did not include beneficial uses by wildlife. Many piscivorous birds such as grebes, terns, cormorants, and mergansers eat fish smaller than those that were sampled by BOG, and sport fish Hg concentrations are not always indicative of wildlife exposure to Hg; therefore, the BOG surveys could not address whether wildlife were at risk due to Hg-induced reproductive impairment in these lakes.

  1. Field irradiator gamma: pre-irradiation occurrence of breeding birds in three boreal habitats

    International Nuclear Information System (INIS)

    Seabloom, R.W.

    1975-10-01

    A trail census was conducted of the breeding birds found in three major habitats in the Field Irradiator Gamma area at the Whiteshell Nuclear Research Establishment, Pinawa, Manitoba. The area sampled was about 10.50 ha in size, and included 4.25 ha of upland forest, 4.75 ha of lowland conifers, and 1.50 ha of black spruce-tamarack bog. Forty-four species of birds were identified, of which 24 were considered to be resident in the study area. The highest population density was observed in the bog, followed by upland forest and lowland conifer respectively. In contrast, species diversity was greatest in the upland forest, while it decreased markedly in the relatively monotypic lowland conifer and bog habitats. (author)

  2. Wood anatomy of Argyroxiphium (Asteraceae): adaptive radiation and ecological correlations

    International Nuclear Information System (INIS)

    Carlquist, S.

    1997-01-01

    Wood anatomy shows close correlation with ecology: A. kauense, A. sandwicense (stem), and A. virescens, which occur in dry localities, show xeromorphic wood patterns. The most mesomorphic woods are those of the bog species A. grayanum and root wood of A. sandwicense. The wood of A. caliginis is xeromorphic, despite the bog habitat of the species, a fact explainable if A. caliginis is a recent entrant into the bog habitat Libriform wall thickness appears correlated with habit. Quantitative features of stem woods of Argyroxiphium are comparable to woods ranging from desert to moist montane forest areas in California. The similarities to woods from each Californian habitat are correlative to the relative moisture availability of the respective Hawaiian habitats of the Argyroxiphium species. (author)

  3. Water and peat chemistry comparisons of natural and peat-harvested peatlands across Canada and their relevance to peatland restoration

    International Nuclear Information System (INIS)

    Windmulder, H.L.; Rochefort, L.; Vitt, D.H.

    1996-01-01

    Water and peat chemistry comparisons of four post-harvested and neighbouring, undisturbed peatlands across Canada show that harvesting alters chemical conditions. Commercial harvesting removes the surface peat and exposes layers farther down the peat deposit. The newly exposed peat layers that were formed in earlier developmental stages of the peatland can be more minerotrophic and/or more variable in chemical composition than undisturbed bog peat. All the harvested sites were originally bogs. Only one site, which had minimal peat removed, presently has chemical conditions somewhat similar to the original surface, with low elemental levels typical of bogs. Two sites are now chemically similar to poor fens and one site is similar to a moderate-rich fen. Levels of sodium, potassium, calcium, magnesium, sulphate and chloride in three of the harvested sites are higher than normal values found in natural, unharvested bogs, and result from the exposure of fen peat. Higher levels of ammonium-nitrogen and nitrate-nitrogen in the peat and water of all the harvested sites are present, with higher ammonium associated with wetter sites and higher nitrate levels associated with drier sites

  4. Variation in the C/N-quotient of peat in relation to decomposition rate and age determination with 210Pb

    International Nuclear Information System (INIS)

    Malmer, N.; Holm, E.

    1984-01-01

    Peat profiles ca. 0.5 m in depth through bog hummocks with Sphagnum spp. have been studied on a subarctic mire in northern Sweden and on some bogs in southern Sweden. The C/N-quotient in the peat decreases with depth due to losses in C during the decay processes. As a result of decay and compaction, the annual peat volume increment at the bottom of the profiles is 4-15% of the increment in the upper parts. On the central bog areas in southern Sweden the decay processes during periods are interrupted at earlier stages which gives rise to a more rapid volumetric peat increment than in the marginal bog areas and in the north. Datings from 210 Pb activity have proved to be reliable only in the lower parts of the profiles (age>50 yr) as lead might be mobile in the upper parts. At the deposition in the catotelm layer after a period of at least 150 yr the organic matter has lost up to 80% of its original carbon. The accumulation of 210 Pb and N shows that the supply of these elements is higher in southern Sweden than in the north. (author)

  5. Relationship between peat geochemistry and depositional environments, Cranberry Island, Maine

    Science.gov (United States)

    Raymond, R.; Cameron, C.C.; Cohen, A.D.

    1987-01-01

    The Heath, Great Cranberry Island, Maine, offers a unique locality for studying lateral and vertical relationships between radically different peat types within 1 km2. The majority of The Heath is a Sphagnum moss-dominated raised bog. Surrounding the raised bog is a swamp/marsh complex containing grass, sedge, Sphagnum moss, alder, tamarack, and skunk cabbage. Swamp/ marsh-deposited peat occurs both around the margins of The Heath and under Sphagnum-dominated peat, which was deposited within the raised bog. A third peat type, dominated by herbaceous aquatics, is present underlying the swamp/marsh-dominated peat but is not present as a dominant botanical community of The Heath. The three peat types have major differences in petrographic characteristics, ash contents, and associated minerals. Sulfur contents range from a low of 0.19 wt.% (dry) within the raised bog to a high of 4.44 wt% (dry) near the west end of The Heath, where swamp/marsh peat occurring directly behind a storm beach berm has been influenced by marine waters. The presence of major geochemical variations within a 1-km2 peat deposit suggests the need for in-depth characterization of potential peat resources prior to use. ?? 1987.

  6. Impact of hydrological variations on modeling of peatland CO2 fluxes: Results from the North American Carbon Program site synthesis

    Science.gov (United States)

    Sulman, Benjamin N.; Desai, Ankur R.; Schroeder, Nicole M.; Ricciuto, Dan; Barr, Alan; Richardson, Andrew D.; Flanagan, Lawrence B.; Lafleur, Peter M.; Tian, Hanqin; Chen, Guangsheng; Grant, Robert F.; Poulter, Benjamin; Verbeeck, Hans; Ciais, Philippe; Ringeval, Bruno; Baker, Ian T.; Schaefer, Kevin; Luo, Yiqi; Weng, Ensheng

    2012-03-01

    Northern peatlands are likely to be important in future carbon cycle-climate feedbacks due to their large carbon pools and vulnerability to hydrological change. Use of non-peatland-specific models could lead to bias in modeling studies of peatland-rich regions. Here, seven ecosystem models were used to simulate CO2fluxes at three wetland sites in Canada and the northern United States, including two nutrient-rich fens and one nutrient-poor,sphagnum-dominated bog, over periods between 1999 and 2007. Models consistently overestimated mean annual gross ecosystem production (GEP) and ecosystem respiration (ER) at all three sites. Monthly flux residuals (simulated - observed) were correlated with measured water table for GEP and ER at the two fen sites, but were not consistently correlated with water table at the bog site. Models that inhibited soil respiration under saturated conditions had less mean bias than models that did not. Modeled diurnal cycles agreed well with eddy covariance measurements at fen sites, but overestimated fluxes at the bog site. Eddy covariance GEP and ER at fens were higher during dry periods than during wet periods, while models predicted either the opposite relationship or no significant difference. At the bog site, eddy covariance GEP did not depend on water table, while simulated GEP was higher during wet periods. Carbon cycle modeling in peatland-rich regions could be improved by incorporating wetland-specific hydrology and by inhibiting GEP and ER under saturated conditions. Bogs and fens likely require distinct plant and soil parameterizations in ecosystem models due to differences in nutrients, peat properties, and plant communities.

  7. Delineation of peatland lagg boundaries from airborne LiDAR

    Science.gov (United States)

    Langlois, Melanie N.; Richardson, Murray C.; Price, Jonathan S.

    2017-09-01

    In Canada, peatlands are the most common type of wetland, but boundary delineation in peatland complexes has received little attention in the scientific literature. Typically, peatland boundaries are mapped as crisp, absolute features, and the transitional lagg zone—the ecotone found between a raised bog and the surrounding mineral land—is often overlooked. In this study, we aim (1) to advance existing approaches for detecting and locating laggs and lagg boundaries using airborne LiDAR surveys and (2) to describe the spatial distribution of laggs around raised bog peatlands. Two contrasting spatial analytical approaches for lagg detection were tested using five LiDAR-derived topographic and vegetation indices: topography, vegetation height, topographic wetness index, the standard deviation of the vegetation's height (as a proxy for the complexity of the vegetation's structure), and local indices of elevation variance. Using a dissimilarity approach (edge-detection, split-moving window analysis), no one variable accurately depicted both the lagg-mineral land and bog-lagg boundaries. Some indicators were better at predicting the bog-lagg boundary (i.e., vegetation height) and others at finding the lagg-mineral land boundary (i.e., topography). Dissimilarity analysis reinforces the usefulness of derived variables (e.g., wetness indices) in locating laggs, especially for those with weak topographic and vegetation gradients. When the lagg was confined between the bog and the adjacent upland, it took a linear form, parallel to the peatland's edge and was easier to predict. When the adjacent mineral land was flat or sloping away from the peatland, the lagg was discontinuous and intermittent and more difficult to predict.

  8. Holocen history of vegetation at “Uroczysko Mokradła” (SW Poland – paleobotanical research

    Directory of Open Access Journals (Sweden)

    Klara Tomaszewska

    2016-09-01

    Full Text Available Two peat bogs were studied in the Bory Dolnośląskie, the forest complex in Lower Silesia (Poland. An Instorf drill was used to collect two peat profiles from the deepest places. The macroremains analysis showed that after the initiation of peat-forming processes phytocoenoses responsible for the deposition of transition sphagnum peat were developed at both locations. Later on, the development of both peat bogs differed. The smaller peat bog continued to develop, whereas the big bog was shifted to ombrotrophic water regime. Therefore, phytocoenoses accumulated 1.3 m of Sphagnum peat. The peat-forming process was initiated at different times in both sites. For the smaller peat bog, it took place during the Atlantic period, while in the case of the larger peat bog – several thousand years later. The first identified forest phytocoenoses in the Atlantic period are mesophilic multi-species deciduous forests. Dry coniferous forests and mixed birch-pine forests grew in dry habitats. Riparian forests occupied lower grounds. In the Subboreal period, the oak–hazel communities initially developed and mixed coniferous forests were partially replaced by light oak forests. The encroachment of spruce, fir, hornbeam, and beech resulted in the development of dry ground forests, including beech–fir woods. The importance of riparian forests increased, whereas in dry grounds pine and mixed coniferous forests continued to occur. In the Subatlantic period, the transformations in forest communities were associated with the spread of hornbeam, beech, and fir and thereby vast fertile habitats were colonized by dry ground communities and beech woods. Pine and mixed forests as well as riparian forests were of lesser importance. Pollen records from the last 500 years showed the clear presence of humans. It was evident from the presence of cereal and weed pollen and from the disturbances in the pollen records caused by peat extraction in the Middle Ages.

  9. Experimental warming delays autumn senescence in a boreal spruce bog: Initial results from the SPRUCE experiment

    Science.gov (United States)

    Richardson, Andrew; Furze, Morgan; Aubrecht, Donald; Milliman, Thomas; Nettles, Robert; Krassovski, Misha; Hanson, Paul

    2016-04-01

    Phenology is considered one of the most robust indicators of the biological impacts of global change. In temperate and boreal regions, long-term data show that rising temperatures are advancing spring onset (e.g. budburst and flowering) and delaying autumn senescence (e.g. leaf coloration and leaf fall) in a wide range of ecosystems. While warm and cold temperatures, day length and insolation, precipitation and water availability, and other factors, have all been shown to influence plant phenology, the future response of phenology to rising temperatures and elevated CO2 still remains highly uncertain because of the challenges associated with conducting realistic manipulative experiments to simulate future environmental conditions. At the SPRUCE (Spruce and Peatland Responses Under Climatic and Environmental Change) experiment in the north-central United States, experimental temperature (0 to +9° C above ambient) and CO2 (ambient and elevated) treatments are being applied to mature, and intact, Picea mariana-Sphagnum spp. bog communities in their native habitat through the use of ten large (approximately 12 m wide, 10 m high) open-topped enclosures. We are tracking vegetation green-up and senescence in these chambers, at both the individual and whole-community level, using repeat digital photography. Within each chamber, digital camera images are recorded every 30 minutes and uploaded to the PhenoCam (http://phenocam.sr.unh.edu) project web page, where they are displayed in near-real-time. Image processing is conducted nightly to extract quantitative measures of canopy color, which we characterize using Gcc, the green chromatic coordinate. Data from a camera mounted outside the chambers (since November 2014) indicate strong seasonal variation in Gcc for both evergreen shrubs and trees. Shrub Gcc rises steeply in May and June, and declines steeply in September and October. By comparison, tree Gcc rises gradually from March through June, and declines gradually from

  10. Surface mapping, organic matter and water stocks in peatlands of the Serra do Espinhaço meridional - Brazil

    Directory of Open Access Journals (Sweden)

    Márcio Luiz da Silva

    2013-10-01

    Full Text Available Peatlands are soil environments that store carbon and large amounts of water, due to their composition (90 % water, low hydraulic conductivity and a sponge-like behavior. It is estimated that peat bogs cover approximately 4.2 % of the Earth's surface and stock 28.4 % of the soil carbon of the planet. Approximately 612 000 ha of peatlands have been mapped in Brazil, but the peat bogs in the Serra do Espinhaço Meridional (SdEM were not included. The objective of this study was to map the peat bogs of the northern part of the SdEM and estimate the organic matter pools and water volume they stock. The peat bogs were pre-identified and mapped by GIS and remote sensing techniques, using ArcGIS 9.3, ENVI 4.5 and GPS Track Maker Pro software and the maps validated in the field. Six peat bogs were mapped in detail (1:20,000 and 1:5,000 by transects spaced 100 m and each transect were determined every 20 m, the UTM (Universal Transverse Mercator coordinates, depth and samples collected for characterization and determination of organic matter, according to the Brazilian System of Soil Classification. In the northern part of SdEM, 14,287.55 ha of peatlands were mapped, distributed over 1,180,109 ha, representing 1.2 % of the total area. These peatlands have an average volume of 170,021,845.00 m³ and stock 6,120,167 t (428.36 t ha-1 of organic matter and 142,138,262 m³ (9,948 m³ ha-1 of water. In the peat bogs of the Serra do Espinhaço Meridional, advanced stages of decomposing (sapric organic matter predominate, followed by the intermediate stage (hemic. The vertical growth rate of the peatlands ranged between 0.04 and 0.43 mm year-1, while the carbon accumulation rate varied between 6.59 and 37.66 g m-2 year-1. The peat bogs of the SdEM contain the headwaters of important water bodies in the basins of the Jequitinhonha and San Francisco Rivers and store large amounts of organic carbon and water, which is the reason why the protection and preservation

  11. Validating modelled data on major and trace element deposition in southern Germany using Sphagnum moss

    Science.gov (United States)

    Kempter, Heike; Krachler, Michael; Shotyk, William; Zaccone, Claudio

    2017-10-01

    Sphagnum mosses were collected from four ombrotrophic bogs in two regions of southern Germany: Upper Bavaria (Oberbayern, OB) and the Northern Black Forest (Nordschwarzwald, NBF). Surfaces of Sphagnum carpets were marked with plastic mesh and, one year later, plant matter was harvested and productivity determined. Major and trace element concentrations (Ag, Al, As, Ba, Bi, Cd, Co, Cr, Cu, Fe, Mn, Mo, Pb, Rb, Sb, Sc, Sr, Th, Ti, Tl, U, V, Zn) were determined in acid digests using sector field ICP-MS. Up to 12 samples (40 × 40 cm) were collected per site, and 6-10 sites investigated per bog. Variation in element accumulation rates within a bog is mostly the result of the annual production rate of the Sphagnum mosses which masks not only the impact of site effects, such as microtopography and the presence of dwarf trees, but also local and regional conditions, including land use in the surrounding area, topography, etc. The difference in productivity between peat bogs results in distinctly higher element accumulation rates at the NBF bogs compared to those from OB for all studied elements. The comparison with the European Monitoring and Evaluation Program (EMEP; wet-only and total deposition) and Modelling of Air Pollutants and Ecosystem Impact (MAPESI; total deposition) data shows that accumulation rates obtained using Sphagnum are in the same range of published values for direct measurements of atmospheric deposition of As, Cd, Cu, Co, Pb, and V in both regions. The accordance is very dependent on how atmospheric deposition rates were obtained, as different models to calculate the deposition rates may yield different fluxes even for the same region. In future studies of atmospheric deposition of trace metals, both Sphagnum moss and deposition collectors have to be used on the same peat bog and results compared. Antimony, however, shows considerable discrepancy, because it is either under-estimated by Sphagnum moss or over-estimated by both atmospheric deposition

  12. Ikke ligefrem noget lysthus

    DEFF Research Database (Denmark)

    Birkholm, Klavs

    2016-01-01

    I sin bog om den amerikanske "neuropsykiater" Robert Heath (1915-99) demonstrerer videnskabsjournalisten Lone Frank nok engang sin forbundethed med den internationale transhumanisme og dens dualistiske forståelse af ånd og materie......I sin bog om den amerikanske "neuropsykiater" Robert Heath (1915-99) demonstrerer videnskabsjournalisten Lone Frank nok engang sin forbundethed med den internationale transhumanisme og dens dualistiske forståelse af ånd og materie...

  13. Æstetik er tilbage som nøgle til at forstå samtiden

    DEFF Research Database (Denmark)

    Sharma, Devika

    2013-01-01

    Casper Christensen er gakket, Hello Kitty er nuttet og konceptkunsten er interessant. Her er tre nye kategorier at forstå senkapitalismen med. I anledning af Sianne Ngais bog "Our aesthetic categories: zany, cute, interesting" .......Casper Christensen er gakket, Hello Kitty er nuttet og konceptkunsten er interessant. Her er tre nye kategorier at forstå senkapitalismen med. I anledning af Sianne Ngais bog "Our aesthetic categories: zany, cute, interesting" ....

  14. Atmospheric Pb and Ti accumulation rates from Sphagnum moss: dependence upon plant productivity.

    Science.gov (United States)

    Kempter, H; Krachler, M; Shotyk, W

    2010-07-15

    The accumulation rates of atmospheric Pb and Ti were obtained using the production rates of Sphagnum mosses collected in four ombrotrophic bogs from two regions of southern Germany: Upper Bavaria (Oberbayern, OB) and the Northern Black Forest (Nordschwarzwald, NBF). Surfaces of Sphagnum carpets were marked with plastic mesh and one year later the production of plant matter was harvested. Metal concentrations were determined in acid digests using sector field ICP-MS employing well established analytical procedures. Up to 12 samples (40 x 40 cm) were collected per site, and 6-10 sites were investigated per bog. Variations within a given sampling site were in the range 2.3-4x for Pb concentrations, 1.8-2.5x for Ti concentrations, 3-8.3x for Pb/Ti, 5.6-7.8x for Pb accumulation rates, and 2.3-6.4x for Ti accumulation rates. However, the median values of these parameters for the sites (6-10 per bog) were quite consistent. The mosses from the bogs in NBF exhibited significantly greater productivity (187-202 g m(-2) a(-1)) compared to the OB peat bogs (71-91 g m(-2) a(-1)), and these differences had a pronounced effect on the Pb and Ti accumulation rates. Highly productive mosses showed no indication of a "dilution effect" of Pb or Ti concentrations, suggesting that more productive plants were simply able to accumulate more particles from the air. The median rates of net Pb accumulation by the mosses are in excellent agreement with the fluxes obtained by direct atmospheric measurements at nearby monitoring stations in both regions (EMEP and MAPESI data).

  15. Mycorrhizal colonisation of highbush blueberry and its native relatives in central Finland

    Directory of Open Access Journals (Sweden)

    A. KASURINEN

    2008-12-01

    Full Text Available Transmission electromicroscopy, trypan blue staining in combination with stereomicroscope analysis and biochemical ergosterol assay were used to study the mycorrhizal symbionts in wild bilberry (Vaccinium myrtillus, bog whortleberry (Vaccinium uliginosum and highbush blueberry (Vaccinium corymbosum roots. TEM-analysis showed that in all species ericoid mycorrhizas formed hyphae coil inside the epidermal root cells. In stereomicroscopic viewing the highest mycorrhizal colonisation was observed in the roots of wild bilberries (51%, whereas according to the ergosterol assay the highest total fungal biomass of roots was found in bog whortleberries (209 mg g-1 of root d. wt. Both ergosterol and microscopical method showed that the mycorrhizal associations in blueberry cultivars and their wild relatives growing on natural soil medium are frequent, although ericoid mycorrhiza formation of highbush blueberries was somewhat weaker than that of wild bilberries and bog whortleberries.

  16. 14th PERG's annual workshop

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2007-07-01

    These proceedings comprise the abstracts for the 12 presentations at the workshop. The papers describe the results of fen restoration and future challenges, a 7-year physiochemistry monitoring program of natural and harvested peatlands at Bois- des-Bel, Sphagnum farming experiments at Lac-St-Jean and development of new mechanized techniques, Cacouna bog after 10 years of harvesting and 30 years abandonment, moisture and climatic forcings of Sphagnum productivity in a cutover peatland, impact of global warming on emissions of greenhouse gases from a fen peatland, a 12-year study of avian recolonization after peat mining of eastern Canadian bogs, plant diversity associated with peatland pool edges, guidelines for cloudberry cultivation in natural and abandoned peatlands, concentrations of suspended sediment downstream from a harvested New Brunswick peat bog, overview of peatland rehabilitation measures in South Africa, and remote sensors for monitoring rehabilitated peatlands.

  17. Atmospheric metal pollution records in the Kovářská Bog (Czech Republic) as an indicator of anthropogenic activities over the last three millennia.

    Science.gov (United States)

    Bohdálková, Leona; Bohdálek, Petr; Břízová, Eva; Pacherová, Petra; Kuběna, Aleš Antonín

    2018-08-15

    Three peat cores were extracted from the Kovářská Bog in the central Ore Mountains to study anthropogenic pollution generated by mining and metallurgy. The core profiles were 14 C dated, and concentrations of selected elements were determined by ICP MS and HG-AAS. Principal component analysis indicated that Pb, Cu, As and Ag may be useful elements for the reconstruction of historical atmospheric pollution. Total and anthropogenic accumulation rates (ARs) of Pb, Cu and As estimated for the last ca. 3500years showed similar chronologies, and revealed twelve periods of elevated ARs of Pb, As and Cu related to possible mining and metallurgic activities. In total, four periods of elevated ARs of Pb, Cu and As were detected during the Middle and Late Bronze Ages, including a distinct Late Bronze Age pollution event between 1030BCE and 910BCE. The Iron Age included three episodes of increased ARs of Pb and As; the first and the most distinctive episode, recorded between 730 and 440BCE, was simultaneous with the Bylany culture during the Hallstatt Period. The Roman Age was characterized by one pollution event, two events were detected in the Middle Ages, and the last two during the modern period. Enhanced element ARs in the late 12th and 15th centuries clearly documented the onset of two periods of intense mining in the Ore Mountains. Metal ARs culminated in ca. 1600CE, and subsequently decreased after the beginning of the Thirty Years' War. The last boom of mining between 1700CE and 1830CE represented the last period of important metallurgical operations. Late Medieval and modern period metal ARs are in good agreement with written documents. Earlier pollution peaks suggest that local metal production could have a much longer tradition than commonly believed; however, archaeological or written evidence is scarce or lacking. Copyright © 2018 Elsevier B.V. All rights reserved.

  18. Life in Ice: Microbial Growth Dynamics and Greenhouse Gas Production During Winter in a Thermokarst Bog Revealed by Stable Isotope Probing Targeted Metagenomics

    Science.gov (United States)

    Blazewicz, S.; White, R. A., III; Tas, N.; Euskirchen, E. S.; Mcfarland, J. W.; Jansson, J.; Waldrop, M. P.

    2016-12-01

    Permafrost contains a reservoir of frozen C estimated to be twice the size of the current atmospheric C pool. In response to changing climate, permafrost is rapidly warming which could result in widespread seasonal thawing. When permafrost thaws, soils that are rich in ice and C often transform into thermokarst wetlands with anaerobic conditions and significant production of atmospheric CH4. While most C flux research in recently thawed permafrost concentrates on the few summer months when seasonal thaw has occurred, there is mounting evidence that sizeable portions of annual CO2 and CH4 efflux occurs over winter or during a rapid burst of emissions associated with seasonal thaw. A potential mechanism for such efflux patterns is microbial activity in frozen soils over winter where gasses produced are partially trapped within ice until spring thaw. In order to better understand microbial transformation of soil C to greenhouse gas over winter, we applied stable isotope probing (SIP) targeted metagenomics combined with process measurements and field flux data to reveal activities of microbial communities in `frozen' soil from an Alaskan thermokarst bog. Field studies revealed build-up of CO2 and CH4 in frozen soils suggesting that microbial activity persisted throughout the winter in soils poised just below the freezing point. Laboratory incubations designed to simulate in-situ winter conditions (-1.5 °C and anaerobic) revealed continuous CH4 and CO2 production. Strikingly, the quantity of CH4 produced in 6 months in frozen soil was equivalent to approximately 80% of CH4 emitted during the 3 month summer `active' season. Heavy water SIP targeted iTag sequencing revealed growing bacteria and archaea in the frozen anaerobic soil. Growth was primarily observed in two bacterial phyla, Firmicutes and Bacteroidetes, suggesting that fermentation was likely the major C mineralization pathway. SIP targeted metagenomics facilitated characterization of the primary metabolic

  19. The systime iBog

    DEFF Research Database (Denmark)

    Ebbesen, Toke Riis

    2016-01-01

    This article proposes a method for critical analysis of design contributions and the material properties of digital textbooks aimed at tertiary schools, in the transition to digital publishing and from paper-based books to digitally available learning materials. The suggested method, adapted from...

  20. Water Table Depth Reconstruction in Ombrotrophic Peatlands Using Biomarker Abundance Ratios and Compound-Specific Hydrogen Isotope Composition

    Science.gov (United States)

    Nichols, J. E.; Jackson, S. T.; Booth, R. K.; Pendall, E. G.; Huang, Y.

    2005-12-01

    Sediment cores from ombrotrophic peat bogs provide sensitive records of changes in precipitation/evaporation (P/E) balance. Various proxies have been developed to reconstruct surface moisture conditions in peat bogs, including testate amoebae, plant macrofossils, and peat humification. Studying species composition of testate amoeba assemblages is time consuming and requires specialized training. Humification index can be influenced by environmental factors other than moisture balance. The plant macrofossil proxy is less quantitative and cannot be performed on highly decomposed samples. We demonstrate that the ratio of C23 alkane to C29 alkane abundance may provide a simple alternative or complementary means of tracking peatland water-table depth. Data for this proxy can be collected quickly using a small sample (100 mg dry). Water-table depth decreases during drought, and abundance of Sphagnum, the dominant peat-forming genus, decreases as vascular plants increase. Sphagnum moss produces mainly medium chain-length alkanes (C21-C25) while vascular plants (grasses and shrubs) produce primarily longer chain-length alkanes (C27-C31). Therefore, C23:C29 n-alkane ratios quantitatively track the water table depth fluctuations in peat bogs. We compared C23:C29 n-alkane ratios in a core from Minden Bog (southeastern Michigan) with water table depth reconstructions based on testate-amoeba assemblages and humification. The 184-cm core spans the past ~3kyr of continuous peat deposition in the bog. Our results indicate that the alkane ratios closely track the water table depth variations, with C29 most abundant during droughts. We also explored the use of D/H ratios in Sphagnum biomarkers as a water-table depth proxy. Compound-specific hydrogen isotope ratio analyses were performed on Sphagnum biomarkers: C23 and C25 alkane and C24 acid. Dry periods are represented in these records by an enrichment of deuterium in these Sphagnum-specific compounds. These events also correlate

  1. Hverdagslivet, sproget og kærligheden

    DEFF Research Database (Denmark)

    Madsen, Peter

    2006-01-01

    Anmelse af Toril Mois bog Ibsens modernisme. Bemærker bl.a. hvordan Mois brug af et begreb om modernisme er problematisk - og i uoverenstemmelse med den overordnede karakter af hendes tilgang til Ibsens dramatik. Udgivelsesdato: 30.10.06......Anmelse af Toril Mois bog Ibsens modernisme. Bemærker bl.a. hvordan Mois brug af et begreb om modernisme er problematisk - og i uoverenstemmelse med den overordnede karakter af hendes tilgang til Ibsens dramatik. Udgivelsesdato: 30.10.06...

  2. Ross - for altid?

    DEFF Research Database (Denmark)

    Blume, Peter Erik

    2011-01-01

    Med baggrund i Jens Ewalds bog om Alf Ross omtaler artiklen en række de problemstillinger, som bogen behandler, samt vurderer den betydning, Ross har haft og måske fortsat har. Afslutningsvis betones den juridiske biografis betydning.......Med baggrund i Jens Ewalds bog om Alf Ross omtaler artiklen en række de problemstillinger, som bogen behandler, samt vurderer den betydning, Ross har haft og måske fortsat har. Afslutningsvis betones den juridiske biografis betydning....

  3. Farvel til partierne, goddag til nødvendigheden

    DEFF Research Database (Denmark)

    Celik, Tim Holst

    2015-01-01

    Teknokrati Peter Mair kortlægger i sin bog 'Ruling the Void' undermineringen af det vestlige partidemokrati. Gennem en opsummering af den empiriske forskning beskriver bogen fremkomsten og udviklingen af ' nødvendighedens politik' på det partipolitiske plan......Teknokrati Peter Mair kortlægger i sin bog 'Ruling the Void' undermineringen af det vestlige partidemokrati. Gennem en opsummering af den empiriske forskning beskriver bogen fremkomsten og udviklingen af ' nødvendighedens politik' på det partipolitiske plan...

  4. Mapping, organic matter mass and water volume of a peatland in Serra do Espinhaço Meridional

    Directory of Open Access Journals (Sweden)

    José Ricardo da Rocha Campos

    2012-06-01

    Full Text Available Peatlands form in areas where net primary of organic matter production exceeds losses due to the decomposition, leaching or disturbance. Due to their chemical and physical characteristics, bogs can influence water dynamics because they can store large volumes of water in the rainy season and gradually release this water during the other months of the year. In Diamantina, Minas Gerais, Brazil, a peatland in the environmental protection area of Pau-de-Fruta ensures the water supply of 40,000 inhabitants. The hypothesis of this study is that the peat bogs in Pau-de-Fruta act as an environment for carbon storage and a regulator of water flow in the Córrego das Pedras basin. The objective of this study was to estimate the water volume and organic matter mass in this peatland and to study the influence of this environment on the water flow in the Córrego das Pedras basin. The peatland was mapped using 57 transects, at intervals of 100 m. Along all transects, the depth of the peat bog, the Universal Transverse Mercator (UTM coordinates and altitude were recorded every 20 m and used to calculate the area and volume of the peatland. The water volume was estimated, using a method developed in this study, and the mass of organic matter based on samples from 106 profiles. The peatland covered 81.7 hectares (ha, and stored 497,767 m³ of water, representing 83.7 % of the total volume of the peat bog. The total amount of organic matter (OM was 45,148 t, corresponding to 552 t ha-1 of OM. The peat bog occupies 11.9 % of the area covered by the Córrego das Pedras basin and stores 77.6 % of the annual water surplus, thus controlling the water flow in the basin and consequently regulating the water course.

  5. Identification of runoff formation with two dyes in a mid-latitude mountain headwater

    Directory of Open Access Journals (Sweden)

    L. Vlček

    2017-06-01

    Full Text Available Subsurface flow in peat bog areas and its role in the hydrologic cycle has garnered increased attention as water scarcity and floods have increased due to a changing climate. In order to further probe the mechanisms in peat bog areas and contextualize them at the catchment scale, this experimental study identifies runoff formation at two opposite hillslopes in a peaty mountain headwater; a slope with organic peat soils and a shallow phreatic zone (0.5 m below surface, and a slope with mineral Podzol soils and no detectable groundwater (> 2 m below surface. Similarities and differences in infiltration, percolation and preferential flow paths between both hillslopes could be identified by sprinkling experiments with Brilliant Blue and Fluorescein sodium. To our knowledge, this is the first time these two dyes have been compared in their ability to stain preferential flow paths in soils. Dye-stained soil profiles within and downstream of the sprinkling areas were excavated parallel (lateral profiles and perpendicular (frontal profiles to the slopes' gradients. That way preferential flow patterns in the soil could be clearly identified. The results show that biomat flow, shallow subsurface flow in the organic topsoil layer, occurred at both hillslopes; however, at the peat bog hillslope it was significantly more prominent. The dye solutions infiltrated into the soil and continued either as lateral subsurface pipe flow in the case of the peat bog, or percolated vertically towards the bedrock in the case of the Podzol. This study provides evidence that subsurface pipe flow, lateral preferential flow along decomposed tree roots or logs in the unsaturated zone, is a major runoff formation process at the peat bog hillslope and in the adjacent riparian zone.

  6. Differential response of carbon fluxes to climate in three peatland ecosystems that vary in the presence and stability of permafrost

    Science.gov (United States)

    Euskirchen, Eugenie S; Edgar, C.W.; Turetsky, M.R.; Waldrop, Mark P.; Harden, Jennifer W.

    2016-01-01

    Changes in vegetation and soil properties following permafrost degradation and thermokarst development in peatlands may cause changes in net carbon storage. To better understand these dynamics, we established three sites in Alaska that vary in permafrost regime, including a black spruce peat plateau forest with stable permafrost, an internal collapse scar bog formed as a result of thermokarst, and a rich fen without permafrost. Measurements include year-round eddy covariance estimates of carbon dioxide (CO2), water, and energy fluxes, associated environmental variables, and methane (CH4) fluxes at the collapse scar bog. The ecosystems all acted as net sinks of CO2 in 2011 and 2012, when air temperature and precipitation remained near long-term means. In 2013, under a late snowmelt and late leaf out followed by a hot, dry summer, the permafrost forest and collapse scar bog were sources of CO2. In this same year, CO2 uptake in the fen increased, largely because summer inundation from groundwater inputs suppressed ecosystem respiration. CO2 exchange in the permafrost forest and collapse scar bog was sensitive to warm air temperatures, with 0.5 g C m−2 lost each day when maximum air temperature was very warm (≥29°C). The bog lost 4981 ± 300 mg CH4 m−2 between April and September 2013, indicating that this ecosystem acted as a significant source of both CO2 and CH4 to the atmosphere in 2013. These results suggest that boreal peatland responses to warming and drying, both of which are expected to occur in a changing climate, will depend on permafrost regime.

  7. Rapid ecosystem shifts in peatlands: linking plant physiology and succession.

    Science.gov (United States)

    Granath, Gustaf; Strengbom, Joachim; Rydin, Håkan

    2010-10-01

    Stratigraphic records from peatlands suggest that the shift from a rich fen (calcareous fen) to an ombrotrophic bog can occur rapidly. This shift constitutes a switch from a species-rich ecosystem to a species-poor one with greater carbon storage. In this process, the invasion and expansion of acidifying bog species of Sphagnum (peat mosses) play a key role. To test under what conditions an acidifying bog species could invade a rich fen, we conducted three experiments, contrasting the bog species S. fucsum with the rich-fen species S. warnstorfii and S. teres. We first tested the effect of calcareous water by growing the three species at different constant height above the water table (HWT; 2, 7, and 14 cm) in a rich-fen pool and measured maximum photosynthetic rate and production and difference in length growth as an indicator of competition. In none of the species was the photosynthetic capacity negatively affected when placed at low HWT, but S. fuscum was a weaker competitor at low HWT. In our second experiment we transplanted the three species into microhabitats with different and naturally varying HWT in a rich fen. Here, S. fuscum nearly ceased to photosynthesize when transplanted to low HWT (brown moss carpet), while it performed similarly to the two rich-fen species at the intermediate level (S. warnstorfii hummock level). In contrast to S. fuscum, the rich-fen sphagna performed equally well in both habitats. The brown moss carpet was seasonally flooded, and in our third experiment we found that S. fuscum, but not S. teres, was severely damaged when submerged in rich-fen water. Our results suggest two thresholds in HWT affecting the ecosystem switch: one level that reduces the risk of submergence and a higher one that makes bog sphagna competitive against the rich-fen species.

  8. H_2 production by the steam reforming of excess boil off gas on LNG vessels

    International Nuclear Information System (INIS)

    Fernández, Ignacio Arias; Gómez, Manuel Romero; Gómez, Javier Romero; López-González, Luis M.

    2017-01-01

    Highlights: • BOG excess in LNG vessels is burned in the GCU without energy use. • The gas management plants need to be improved to increase efficiency. • BOG excess in LNG vessels is used for H_2 production by steam reforming. • The availability of different fuels increases the versatility of the ship. - Abstract: The gas management system onboard LNG (Liquid Natural Gas) vessels is crucial, since the exploitation of the BOG (Boil Off Gas) produced is of utmost importance for the overall efficiency of the plant. At present, LNG ships with no reliquefaction plant consume the BOG generated in the engines, and the excess is burned in the GCU (Gas Combustion Unit) without any energy use. The need to improve the gas management system, therefore, is evident. This paper proposes hydrogen production through a steam reforming plant, using the excess BOG as raw material and thus avoiding it being burned in the GCU. To test the feasibility of integrating the plant, an actual study of the gas management process on an LNG vessel with 4SDF (4 Stroke Dual Fuel) propulsion and with no reliquefaction plant was conducted, along with a thermodynamic simulation of the reforming plant. With the proposed gas management system, the vessel disposes of different fuels, including H_2, a clean fuel with zero ozone-depleting emissions. The availability of H_2 on board in areas with strict anti-pollution regulations, such as ECAs (Emission Control Area), means that the vessel may be navigated without using fossil fuels which generate CO_2 and SO_X emissions. Moreover, while at port, Cold Ironing is avoided, which entails high costs. Thus it is demonstrated that the installation of a reforming plant is both energetically viable and provides greater versatility to the ship.

  9. A new boil-off gas re-liquefaction system for LNG carriers based on dual mixed refrigerant cycle

    Science.gov (United States)

    Tan, Hongbo; Shan, Siyu; Nie, Yang; Zhao, Qingxuan

    2018-06-01

    A new boil-off gas (BOG) re-liquefaction system for LNG carriers has been proposed to improve the system energy efficiency. Two cascade mixed refrigerant cycles (or dual mixed refrigerant cycle, DMR) are used to provide the cooling capacity for the re-liquefaction of BOG. The performance of the new system is analysed on the basis of the thermodynamic data obtained in the process simulation in Aspen HYSYS software. The results show that the power consumed in the BOG compressor and the high-temperature mixed refrigerant compressor could be saved greatly due to the reduced mass flow rates of the processed fluids. Assuming the re-liquefaction capacity of the investigated system is 4557.6 kg/h, it is found that the total power consumption can be reduced by 25%, from 3444 kW in the existing system to 2585.8 kW in the proposed system. The coefficient of performance (COP) of 0.25, exergy efficiency of 41.3% and the specific energy consumption (SEC) of 0.589 kWh/kg(LNG) could be achieved in the new system. It exhibits 33% of improvement in the COP and exergy efficiency in comparison with the corresponding values of the existing system. It indicates that employing the DMR based BOG re-liquefaction system could improve the system energy efficiency of LNG carriers substantially.

  10. Geomorphology and landscape organization of a northern peatland complex

    Science.gov (United States)

    Richardson, M. C.

    2012-12-01

    The geomorphic evolution of northern peatlands is governed by complex ecohydrological feedback mechanisms and associated hydro-climatic drivers. For example, prevailing models of bog development (i.e. Ingram's groundwater mounding hypothesis and variants) attempt to explicitly link bog dome characteristics to the regional climate based on analytical and numerical models of lateral groundwater flow and the first-order control of water table position on rates of peat accumulation. In this talk I will present new results from quantitative geomorphic analyses of a northern peatland complex at the De Beers Victor diamond mine site in the Hudson Bay Lowlands of northern Ontario. This work capitalizes on spatially-extensive, high-resolution topographic (LiDAR) data to rigorously test analytical and numerical models of bog dome development in this landscape. The analysis and discussion are then expanded beyond individual bog formations to more broadly consider ecohydrological drivers of landscape organization, with implications for understanding and modeling catchment-scale runoff response. Results show that in this landscape, drainage patterns exhibit relatively well-organized characteristics consistent with observed runoff responses in six gauged research catchments. Interpreted together, the results of these geomorphic and hydrologic analyses help refine our understanding of water balance partitioning among different landcover types within northern peatland complexes. These findings can be used to help guide the development of appropriate numerical model structures for hydrologic prediction in ungauged peatland basins of northern Canada.

  11. Om at oversætte Mead

    DEFF Research Database (Denmark)

    Willert, Søren

    2005-01-01

    George Herbert Mead har skrevet en rigtig dårlig bog, der dog også er en klassiker. "sindet, selvet og samfundet" er den blevet til i en udgivelsesklar dansk udgave- og oversættelsen er en historie i seig selv.......George Herbert Mead har skrevet en rigtig dårlig bog, der dog også er en klassiker. "sindet, selvet og samfundet" er den blevet til i en udgivelsesklar dansk udgave- og oversættelsen er en historie i seig selv....

  12. Comparison between reverse Brayton and Kapitza based LNG boil-off gas reliquefaction system using exergy analysis

    Science.gov (United States)

    Kochunni, Sarun Kumar; Chowdhury, Kanchan

    2017-02-01

    LNG boil-off gas (BOG) reliquefaction systems in LNG carrier ships uses refrigeration devices which are based on reverse Brayton, Claude, Kapitza (modified Claude) or Cascade cycles. Some of these refrigeration devices use nitrogen as the refrigerants and hence nitrogen storage vessels or nitrogen generators needs to be installed in LNG carrier ships which consume space and add weight to the carrier. In the present work, a new configuration based on Kapitza liquefaction cycle which uses BOG itself as working fluid is proposed and has been compared with Reverse Brayton Cycle (RBC) on sizes of heat exchangers and compressor operating parameters. Exergy analysis is done after simulating at steady state with Aspen Hysys 8.6® and the comparison between RBC and Kapitza may help designers to choose reliquefaction system with appropriate process parameters and sizes of equipment. With comparable exergetic efficiency as that of an RBC, a Kaptiza system needs only BOG compressor without any need of nitrogen gas.

  13. 210Pb content in phytocoenoses with cranberry

    International Nuclear Information System (INIS)

    Dushanskene-Duzh, R.F.; Butkus, V.F.

    1983-01-01

    The purpose of the paper is to study 210 Pb concentration levels in different biotopes of cranberry growing (Oxycoccus palustris Pers.), to determine concentration distribution of this radionuclide over the organs of this plant and to reveal the effect of ecological conditions on concentration levels. Material is collected in southern Lithua in five biotopes in the form of certain belts of plant communities: reed brushwood (mesotrophic place of groWth), lake mire (mesotrophic place of growing), grassy-forest belt (oligotropic bog), forest belt (low slope of the upper ologotrophic bog), head mire (central part of oligotrophic bog). It is stated that levels and distribution of 210 Pb concentration in cranberry organs growing in oligotrophic and mesotrophic biotopes are approximately equal. Its largest part is concentrated in roots, then come shoots with leaves and only negligible part falls on fruits. Direct correlation exists between 210 Pb concentration in roots and shoots with leaves, and back correlation exists between shoots with leaves and fruits

  14. Seasonal methane dynamics in three temperate grasslands on peat

    DEFF Research Database (Denmark)

    Schäfer, Carolyn; Elsgaard, Lars; Hoffmann, Carl Christian

    2012-01-01

    Background and Aims Drained peatlands are considered to be insignificant CH4 sources, but the effect of drainage on CH4 dynamics has not been extensively studied. We investigated seasonal dynamics of CH4 in two fen peat soils and one bog peat soil under permanent grassland in Denmark. Methods Soil......, even though soil CH4 concentrations of up to 155 and 1000 μmol CH4 dm−3 were measured in one of the fen peats and in the bog peat, respectively. Significant CH4 concentrations were observed above the water table. Methane production assays confirmed the presence of viable methanogens in the upper parts...... of the bog peat soil. The aerenchymous plant Juncus effusus L. liberated CH4 from the peat at rates of up to 3.3 mg CH4 m−2 h−1. No CH4 dynamics were observed in the second fen peat which, in contrast to the other two sites, had high sulfate concentrations. Conclusions Peat type and the distribution...

  15. Installation Restoration Program. Phase 2. Confirmation/Quantification. Stage 1. Problem Confirmation Study: Otis Air National Guard Base, Massachusetts, Air National Guard Support Center, Andrews Air Force Base, Maryland.

    Science.gov (United States)

    1985-09-04

    six surface water sampling locations are recommended. If there are any existing private wells off-Base in the vicinity of the Cranberry Bog south of the... Cranberry Bog *Scale: 1" 800’ 0800 0 400 800 FIGURE 1-9 SITE MAP FOR PETROL FUEL STORAGE AREA 102 A _XA LA.*. the middle 1950’s, the 14,000 and 22,500 balrel...flat, plain sloping gently to the south. Elevations generally range from 100 to 140 feet above mean sea level (MSL). Numerous depressions , frequently

  16. Lille spejl i hjernen dér

    DEFF Research Database (Denmark)

    Wallentin, Mikkel

    2014-01-01

    Myte? Spejlneuroner er blevet brugt til at forklare både læring, empati og sprog, og tidligere i år modtog Giacomo Rizzolatti den store Brain Prize for opdagelsen af dem. Ny bog er kritisk over for fænomenet.......Myte? Spejlneuroner er blevet brugt til at forklare både læring, empati og sprog, og tidligere i år modtog Giacomo Rizzolatti den store Brain Prize for opdagelsen af dem. Ny bog er kritisk over for fænomenet....

  17. Darwin på arabisk

    DEFF Research Database (Denmark)

    Riexinger, Martin Thomas

    2014-01-01

    Det var to revolutionære spor, som i begyndelsen af 1800-talet gødede jorden for introduktionen af Darwins evolutionsteori i Mellemøsten, og muslimer spillede stort set ingen rolle for den udviklingen. Ny bog om islam og evolutionsteorien.......Det var to revolutionære spor, som i begyndelsen af 1800-talet gødede jorden for introduktionen af Darwins evolutionsteori i Mellemøsten, og muslimer spillede stort set ingen rolle for den udviklingen. Ny bog om islam og evolutionsteorien....

  18. From Leaf Synthesis to Senescence: n-Alkyl Lipid Abundance and D/H Composition Among Plant Species in a Temperate Deciduous Forest at Brown's Lake Bog, Ohio, USA

    Science.gov (United States)

    Freimuth, E. J.; Diefendorf, A. F.; Lowell, T. V.

    2014-12-01

    The hydrogen isotope composition (D/H, δD) of terrestrial plant leaf waxes is a promising paleohydrology proxy because meteoric water (e.g., precipitation) is the primary hydrogen source for wax synthesis. However, secondary environmental and biological factors modify the net apparent fractionation between precipitation δD and leaf wax δD, limiting quantitative reconstruction of paleohydrology. These secondary factors include soil evaporation, leaf transpiration, biosynthetic fractionation, and the seasonal timing of lipid synthesis. Here, we investigate the influence of each of these factors on n-alkyl lipid δD in five dominant deciduous angiosperm tree species as well as shrubs, ferns and grasses in the watershed surrounding Brown's Lake Bog, Ohio, USA. We quantified n-alkane and n-alkanoic acid concentrations and δD in replicate individuals of each species at weekly to monthly intervals from March to October 2014 to assess inter- and intraspecific isotope variability throughout the growing season. We present soil, xylem and leaf water δD from each individual, and precipitation and atmospheric water vapor δD throughout the season to directly examine the relationship between source water and lipid isotope composition. These data allow us to assess the relative influence of soil evaporation and leaf transpiration among plant types, within species, and along a soil moisture gradient throughout the catchment. We use leaf water δD to approximate biosynthetic fractionation for each individual and test whether this is a species-specific and seasonal constant, and to evaluate variation among plant types with identical growth conditions. Our high frequency sampling approach provides new insights into the seasonal timing of n-alkane and n-alkanoic acid synthesis and subsequent fluctuations in concentration and δD in a temperate deciduous forest. These results will advance understanding of the magnitude and timing of secondary influences on the modern leaf wax

  19. How do climate and human impact affect Sphagnum peatlands under oceanic-continental climatic conditions? 2000 years of fire and hydrological history of a bog in Northern Poland

    Science.gov (United States)

    Marcisz, Katarzyna; Tinner, Willy; Colombaroli, Daniele; Kołaczek, Piotr; Słowiński, Michał; Fiałkiewicz-Kozieł, Barbara; Lamentowicz, Mariusz

    2014-05-01

    Climate change affects many natural processes and the same applies to human impact For instance climate change and anthropogenic activities may cause increased fire activity or change peatland dynamics. Currently it is still unknown how Sphagnum peatlands in the oceanic-continental transition zone of Poland may respond to combined effects of heat waves, drought and fire. The aim of the study was to reconstruct the last 2000 years palaeohydrology and fire history at Linje bog in Northern Poland. The main task was to determine the drivers of fire episodes, particularly to identify climatic and anthropogenic forcing. A two-meter peat core was extracted and subsampled with a high resolution. Micro- and macroscopic charcoal analyses were applied to determine past fire activity and the results compared with palaeohydrological reconstructions based on testate amoeba analysis. Palynological human indicators were used to reconstruct human activity. A depth-age model including 20 14C dates was constructed to calculate peat accumulation rates and charcoal influx. We hypothesised that: 1) fire frequency in Northern Poland was determined by climatic conditions (combination of low precipitation and heat waves), as reflected in peatland water table, and that 2) past fire episodes in the last millennium were intensified by human activity. Furthermore climate may have influenced human activity over harvest success and the carrying capacity. Our study shows that fire was important for the studied ecosystem, however, its frequency has increased in the last millennium in concomitance with land use activities. Landscape humanization and vegetation opening were followed by a peatland drying during the Little Ice Age (from ca. AD 1380). Similarly to other palaeoecological studies from Poland, Linje peatland possessed an unstable hydrology during the Little Ice Age. Increased fire episodes appeared shortly before the Little Ice Age and most severe fires were present in the time when

  20. Association between obesity and various parameters of physical fitness in Korean students.

    Science.gov (United States)

    Kim, Jae-Woo; Seo, Dong-Il; Swearingin, B; So, Wi-Young

    2013-01-01

    The purpose of this study was to evaluate the association between the types of obesity classified according to the body mass index (BMI) and/or waist circumference (WC) and the various parameters of physical fitness in Korean college students. BMI, WC, and fitness assessments were performed on 726 male college student volunteers who visited a public health center in Seoul, Korea. Classification based on BMI and/or WC was established according to the data in the WHO's Asia-Pacific standard report, and the subjects were divided into the following 4 groups: (1) obese as determined by BMI, but not WC (BMI Obesity Group, BOG); (2) obese as determined by WC, but not BMI (WC Obesity Group, WOG); (3) obese as determined by both BMI and WC (BWOG); and (4) non-obese normal group (NG). Fitness assessment parameters such as cardiorespiratory endurance, cardiovascular function, muscular endurance, muscular strength, flexibility, power, agility, and balance were evaluated through the following measurements: time required to run 1.5 km, physical efficiency index (PEI), vital capacity (ℓ), push-ups (reps/2 min), sit-ups (reps/2 min), back strength (kg), grip strength (kg), sit and reach distance (cm), vertical jumps (cm), whole body reaction time (ms), side steps (reps/30 s), and maximum time of standing on 1 foot with closed eyes (s). The odds ratios (OR) (95% confidence interval [CI]) of the BOG and WOG for the 1.5-km run were 0.367 (0.192-0.701) and 0.168 (0.037-0.773), respectively; of the BWOG and WOG for vital capacity were 5.900 (1.298-26.827) and 5.364 (1.166-24.670), respectively; of the BOG for push-ups was 0.517 (0.279-0.959); of the WOG for back strength was 0.206 (0.045-0.945); of the BWOG and BOG for grip strength were 5.973 (1.314-27.157) and 2.036 (1.089-3.807), respectively; and of the BOG for the whole body reaction time was 0.405 (0.212-0.774), as compared to the NG. We conclude that all 3 types of obesity (classified into the BWOG, BOG, and WOG) result in

  1. A preliminary study on the behavior of trace elements in sediment cores from Ilha Grande (Rio de Janeiro State) by neutron activation analysis

    Energy Technology Data Exchange (ETDEWEB)

    Wasserman, Julio Cesar [Universidade Federal Fluminense, Niteroi, RJ (Brazil). Dept. de Geoquimica; Figueiredo, Ana Maria G. [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil); Figueira, Andre Luiz [Universidade do Estado, Rio de Janeiro, RJ (Brazil). Dept. de Oceanografia; Kelecom, Alphonse [Universidade Federal Fluminense, Niteroi, RJ (Brazil). Dept. de Biologia Geral

    2002-07-01

    The present work aims to identify atmospheric and marine inputs of 9 metals (Ba, Co, Cr, Cs, Fe, Hf, Rb, Sc, Zn), 8 rare earths (La, Ce, Nd, Sm, Eu, Tb, Yb e Lu), 2 actinides (U, Th) and 3 non-metals (As, Sb, Se) in sediment cores from a remote area, the Biological Reserve of Praia do Sul, Ilha Grande, Rio de Janeiro, Brazil. The sediment cores were sampled in a peat bog (out of the tidal reach) and in a mangrove, downstream of the peat bog. The analytical technique employed was Instrumental Neutron Activation Analysis. The samples were irradiated for 16 hours at a thermal neutron flux of 10{sup 12} n cm{sup -2} s{sup -1} at the IEA-R1 reactor of IPEN. The measurements of the induced gamma-ray activity were carried out by high resolution gamma spectrometry, with an hyperpure Ge detector. A preliminary sediment dating with Po-210 was also carried out by applying radiochemical procedures and measurements were done in an Alfa spectrometer The results indicate that the peat bog core present a slight surface enrichment that can be attributed to atmospheric inputs. Increasing concentrations of metals with age is probably due to history of soil occupation. In the mangrove core, no significant increase in concentration could be detected in the surface sediments (except for Zn) confirming the suitability of the peat bog core as a tracer for atmospheric inputs. (author)

  2. A preliminary study on the behavior of trace elements in sediment cores from Ilha Grande (Rio de Janeiro State) by neutron activation analysis

    International Nuclear Information System (INIS)

    Wasserman, Julio Cesar; Figueira, Andre Luiz; Kelecom, Alphonse

    2002-01-01

    The present work aims to identify atmospheric and marine inputs of 9 metals (Ba, Co, Cr, Cs, Fe, Hf, Rb, Sc, Zn), 8 rare earths (La, Ce, Nd, Sm, Eu, Tb, Yb e Lu), 2 actinides (U, Th) and 3 non-metals (As, Sb, Se) in sediment cores from a remote area, the Biological Reserve of Praia do Sul, Ilha Grande, Rio de Janeiro, Brazil. The sediment cores were sampled in a peat bog (out of the tidal reach) and in a mangrove, downstream of the peat bog. The analytical technique employed was Instrumental Neutron Activation Analysis. The samples were irradiated for 16 hours at a thermal neutron flux of 10 12 n cm -2 s -1 at the IEA-R1 reactor of IPEN. The measurements of the induced gamma-ray activity were carried out by high resolution gamma spectrometry, with an hyperpure Ge detector. A preliminary sediment dating with Po-210 was also carried out by applying radiochemical procedures and measurements were done in an Alfa spectrometer The results indicate that the peat bog core present a slight surface enrichment that can be attributed to atmospheric inputs. Increasing concentrations of metals with age is probably due to history of soil occupation. In the mangrove core, no significant increase in concentration could be detected in the surface sediments (except for Zn) confirming the suitability of the peat bog core as a tracer for atmospheric inputs. (author)

  3. Terrain Analysis Procedural Guide for Soil. Report Number 6 in the ETL Series on Guides for Army Terrain Analysts

    Science.gov (United States)

    1981-02-01

    01 T3 Swamp Pt. OH. CH. MH. OL T4 Peat Bog Pt T5 . - Peat Cuttings Pt T6 Cranberry Bog Pt. OH. CH. MH, OL T7 Rice holds Pt. OH, CH, MH, OL ’ ~Known...Commonly Associated Soils Landlorm/erc Climate Horizon USCS Symbol Coastal Plain unspecified unspecified OL. ML. CL. ML-CL, MH. Depressions CH, OH...total sample. SALINA A salt marsh or pond located adjacent to the sea, but not open to the sea. SALT PAN Any flat area or natural depression where water

  4. Do big gods cause anything?

    DEFF Research Database (Denmark)

    Geertz, Armin W.

    2014-01-01

    Dette er et bidrag til et review symposium vedrørende Ara Norenzayans bog Big Gods: How Religion Transformed Cooperation and Conflict (Princeton University Press 2013). Bogen er spændende men problematisk i forhold til kausalitet, ateisme og stereotyper om jægere-samlere.......Dette er et bidrag til et review symposium vedrørende Ara Norenzayans bog Big Gods: How Religion Transformed Cooperation and Conflict (Princeton University Press 2013). Bogen er spændende men problematisk i forhold til kausalitet, ateisme og stereotyper om jægere-samlere....

  5. Iodine and microbial interactions in an organic soil

    International Nuclear Information System (INIS)

    Sheppard, M.I.; Hawkins, J.L.

    1995-01-01

    Iodine-129 in groundwater discharging from a geological disposal vault could accumulate in wetlands by chemical sorption onto low pH, highly organic solid surfaces or by direct or indirect microbial processes. Previous work indicated that saturation of anion sorption sites, microbial toxicity, or swamping of the I reduction/oxidation reaction decreased the retention of a wetland sphagnum for iodine with increased iodine porewater concentrations. Bog water and peat of an iodine-rich bog were studied to elucidate the role of micro-organisms in the retention and accumulation of iodine in a temperate wetland. (author)

  6. Sphagnum farming in Germany – a review of progress

    Directory of Open Access Journals (Sweden)

    G. Gaudig

    2014-02-01

    Full Text Available In ombrotrophic, nutrient-poor peatlands, the cultivation of peatmoss (Sphagnum spp. is a promising paludiculture option. Since 2001 we have been studying peatmoss cultivation (‘Sphagnum farming’ in greenhouse and field experiments, paying special attention to propagation, propagule storage, establishment, productivity and regeneration. Our studies show that Sphagnum farming in Germany may provide a sustainable high-quality alternative to fossil white peat as a raw material for horticultural growing media. Sphagnum farming is, furthermore, a climate-friendly and sustainable land use option for abandoned cut-over bogs and degraded bog grassland.

  7. Studying the removal of the pollutants from wetlands

    Directory of Open Access Journals (Sweden)

    Nevzorov Aleksandr Leonidovich

    2015-04-01

    Full Text Available Wetlands, considered as the territories unfit for agriculture and building, in the recent past served as the places for the industrial and municipal waste accommodation. That’s why the problems, connected with the studies of pollution and recovery duration of bogs, are rather current nowadays. The aim of this research is studying carrying out of pollutants from the polluted marsh massif. The object of the research is the Konnick bog, where the discharge of waste water from the hydrolysis plant and dumping of ash and sawmilling waste started in the fifties. The emission of waste water from the city’s treatment facilities also took place there. The Konnick bog is situated in the Arkhangelsk region. The network of stations for the ground and surface water monitoring was organized on the territory of the bog in 2004. The monitoring showed that the ground water composition has the excess of ammonium salt, phosphates, petroleum products, lignin substances, phenols, etc. Since 2004 there is a gradual decrease in concentration of the majority of pollutant, which is connected with the end of dumping of waste and discharge of waste water from the hydrolysis. In our opinion the decrease in the polluting substances concentration in marsh waters (self-cleaning happens due to dilution of ground waters. The process of the pollutants removal from the peat was investigated with the help of a specially constructed device. The researches offered an equation, which describes the relation between the relative concentration of pollutants and the ground water flow. The analysis of the results of the peat ablution showed that in order to reduce the concentration of most pollutants the water should be filtered through the peat (at least 1 liter per 1 gram of dry peat. Using the received equation the settlement curves of pollutant concentration reduction in a bog were obtained. The curves obtained according to laboratory researches correlate rather well with the data

  8. Carbon budget of oligotrophic mires in the Southern Taiga of Western Siberia under anthropogenic impact

    Science.gov (United States)

    Golovatskaya, Eugenia; Dyukarev, Egor

    2010-05-01

    Role of peatlands in the global greenhouse gases budget is highly relevant. According to present estimates peatlands in undisturbed conditions act as a sink for the atmospheric carbon. Anthropogenic impact on peatlands (melioration, changes in land use, influence of underground water catchments) results in water table lowering, changing in vegetation cover, and degradation of peat deposit. Peatlands could provide a significant positive feedback for climate changes if warming and peatlands drying stimulates bulk soil organic matter decomposition which enhances CO2 release to the atmosphere. Western Siberian peatlands usually represented big bog massifs. Big peatlands have higher stability to external influence. Small peatlands have all signs of big bogs but react on changes in environmental variables more quickly. The present study is devoted to investigation of primary carbon fluxes (CO2 emission and net primary productivity) and carbon balance at oligotrophic bogs in native condition (key area "Bakchar") and under anthropogenic impact (key area "Ob'-Tom'"). The key area "Bakchar" is located between the Iksa and Bakchar rivers (56o58`N 82o36`E) at the Bakcharskoe bog (area 1400 km2). The key area "Ob'-Tom'"is located in the northern part of Ob' and Tom' interfluve (56o21`N 82o31`E). The "Bakchar" key area includes the following ecosystems: pine- shrub-sphagnum community, a similar community with stunted (low) pine trees, and sedge-sphagnum fen. Two small peatlands were studied at Ob' and Tom' interfluve. Kirsanovskoe bog includes pine- shrub-sphagnum community and sedge fen. Timiryazevskoe bog was represented by pine- shrub-sphagnum (TPSS) community and sedge fen. An infrared gas analyzer OPTOGAS 500.4 (OPTEC Corp., St.-Petersburg, Russia) attached to a static opaque plastic been used for carbon dioxide emission measurements. The net primary productivity was measured by clipping method (Golovatskaya and Dyukarev, Plant Soil 2009). Peatlands at "Ob'-Tom'" key area

  9. Ages of 24 widespread tephras erupted since 30,000 years ago in New Zealand, with re-evaluation of the timing and palaeoclimatic implications of the Lateglacial cool episode recorded at Kaipo bog

    Science.gov (United States)

    Lowe, David J.; Blaauw, Maarten; Hogg, Alan G.; Newnham, Rewi M.

    2013-08-01

    Tephras are important for the NZ-INTIMATE project because they link all three records comprising the composite inter-regional stratotype developed for the New Zealand climate event stratigraphy (NZ-CES). Here we firstly report new calendar ages for 24 widespread marker tephras erupted since 30,000 calendar (cal.) years ago in New Zealand to help facilitate their use as chronostratigraphic dating tools for the NZ-CES and for other palaeoenvironmental and geological applications. The selected tephras comprise 12 rhyolitic tephras from Taupo, nine rhyolitic tephras from Okataina, one peralkaline rhyolitic tephra from Tuhua, and one andesitic tephra each from Tongariro and Egmont/Taranaki volcanic centres. Age models for the tephras were obtained using three methods: (i) 14C-based wiggle-match dating of wood from trees killed by volcanic eruptions (these dates published previously); (ii) flexible depositional modelling of a high-resolution 14C-dated age-depth sequence at Kaipo bog using two Bayesian-based modelling programs, Bacon and OxCal's P_Sequence function, and the IntCal09 data set (with SH offset correction -44 ± 17 yr); and (iii) calibration of 14C ages using OxCal's Tau_Boundary function and the SHCal04 and IntCal09 data sets. Our preferred dates or calibrated ages for the 24 tephras are as follows (youngest to oldest, all mid-point or mean ages of 95% probability ranges): Kaharoa AD 1314 ± 12; Taupo (Unit Y) AD 232 ± 10; Mapara (Unit X) 2059 ± 118 cal. yr BP; Whakaipo (Unit V) 2800 ± 60 cal. yr BP; Waimihia (Unit S) 3401 ± 108 cal. yr BP; Stent (Unit Q) 4322 ± 112 cal. yr BP; Unit K 5111 ± 210 cal. yr BP; Whakatane 5526 ± 145 cal. yr BP; Tuhua 6577 ± 547 cal. yr BP; Mamaku 7940 ± 257 cal. yr BP; Rotoma 9423 ± 120 cal. yr BP; Opepe (Unit E) 9991 ± 160 cal. yr BP; Poronui (Unit C) 11,170 ± 115 cal. yr BP; Karapiti (Unit B) 11,460 ± 172 cal. yr BP; Okupata 11,767 ± 192 cal. yr BP; Konini (bed b) 11,880 ± 183 cal. yr BP; Waiohau 14,009 ± 155

  10. Contributions of palynology in the reconstruction of livestock impact on the surroundings of Rascafria (Madrid) during the recent Holocene; Aportaciones de la palinologia en la reconstruccion del impacto ganadero, en los alrededores de Rascafria (Madrid), durante el Holoceno reciente

    Energy Technology Data Exchange (ETDEWEB)

    Gomez-Gonzalez, C.; Ruiz Zapata, M. B.; Lopez-Saez, J. A.; Gil Garcia, M. J.

    2009-07-01

    We present the results obtained from the palaeocological studies about human impact on the vegetal landscape of a peat bog located in Resurface (Lozoya Valley, Madrid, Central Spain). Palynomorph analysis allows to identify the kind and intensity of human activity and its relation to the trophic changes in the peat bog during the late Holocene (2455{+-}35 BP). Pollen record reveals an anthropic Mediterranean landscape mainly composed by pastures used for grazing. Non Pollen Palynomorphs (NPP) and pH and conductivity sediment have revealed as useful tools for detection of trophic conditions and land use changes. (Author)

  11. En bog om Michael Strunge

    DEFF Research Database (Denmark)

    Mai, Anne-Marie

    Antologi med bidrag om Michael Strunges forfatterskab. Bidrag af Anne-Marie Mai, Jørgen Aabenhus, Marianne Stidsen, Moritz Schramm, Tue Andersen Nexø, Lars Bukdahl, Jon Helt Haarder, Rune Kühl er optaget efter fagfællesbedømmelse. Antologien er redigeret af Anne-Marie Mai og Jørgen Aabenhus....

  12. Integrating the EMPD with an Alpine altitudinal training set to reconstruct climate variables in Holocene pollen records from high-altitude peat bogs

    Science.gov (United States)

    Furlanetto, Giulia; Badino, Federica; Brunetti, Michele; Champvillair, Elena; De Amicis, Mattia; Maggi, Valter; Pini, Roberta; Ravazzi, Cesare; Vallé, Francesca

    2016-04-01

    Temperatures and precipitation are the main environmental factors influencing vegetation and pollen production. Knowing the modern climate optima and tolerances of those plants represented in fossil assemblages and assuming that the relationships between plants and climate in the past are not dissimilar from the modern ones, fossil pollen records offer many descriptors to reconstruct past climate variables. The aim of our work is to investigate the potential of high-altitude pollen records from an Alpine peat bog (TBValter, close to the Ruitor Glacier, Western Italian Alps) for quantitative paleoclimate estimates. The idea behind is that high-altitude ecosystems are more sensitive to climate changes, especially to changes in July temperatures that severely affect the timberline ecotone. Meantime, we met with difficulties when considering the factors involved in pollen dispersal over a complex altitudinal mountain pattern, such as the Alps. We used the EMPD-European Modern Pollen Database (Davis et al., 2013) as modern training set to be compared with our high-altitude fossil site. The EMPD dataset is valuable in that it provides a large geographic coverage of main ecological and climate gradients (at sub-continental scale) but lacks in sampling of altitudinal gradients and high-altitude sites in the Alps. We therefore designed an independent altitudinal training set for the alpine valley hosting our fossil site. 27 sampling plots were selected along a 1700m-elevational transect. In a first step, each plot was provided with (i) 3 moss polsters collected following the guidelines provided by Cañellas-Boltà et al. (2009) and analyzed separately to account for differences in pollen deposition at small scale, (ii) morphometrical parameters obtained through a high-resolution DEM, and (iii) temperature and precipitation were estimated by means of weighted linear regression of the meteorological variable versus elevation, locally evaluated for each site (Brunetti et al

  13. A New Appraisal of Northern Peatlands and Global Atmospheric Methane Over the Holocene

    Science.gov (United States)

    MacDonald, G. M.; Holmquist, J. R.; Kremenetski, K.; Loisel, J.

    2015-12-01

    Use of large databases of peat cores to examine linkages between northern peatlands and atmospheric CH4 over the Holocene has been prone to uncertainties regarding 1. comparability of radiocarbon techniques and material dated, 2. appropriate summed probability distributions, 3. spatial representativeness of the sites, particularly in capturing sites south of the subarctic, 4. potential impacts of local lateral peatland expansion versus continental-scale peatland initiation, particularly in the late Holocene, and 5. impacts of changes in the proportion of high methane-producing fens vs Sphagnum bogs. We present a comparison of radiocarbon measurements from conventional counts, atomic mass spectrometry and differing peat materials to demonstrate a general compatibility of the various types of dates. We compare and apply several summed probability distribution methods to minimize any statistical bias in our analysis. We then present our analysis of a new data set of 7571 peatland cores from 4420 sites that extend into the temperate zone. Of these, 3732 cores inform on lateral expansion and 329 dates constrain the timing of fen-bog transition. Based on these data in original and gridded form we show that widespread peat initiation commenced at 16 kcal yr BP and reached a maximum rate at 11-8 kcal yr BP. Most sites began as fens, and peak transition to bogs occurred between 5 and 3 kcal yr BP, with a 1000 year lag between Eurasia and North America. There is no global late Holocene increase in lateral expansion. Based on modeled northern peatland area and ratio of fen/bog sites, CH4 production from northern peatlands increased rapidly from 11 to 9 cal yr BP, followed by slower increase until reaching a maximum at 5 kcal yr BP at 25 Tg per yr. From 4 kcal yr BP to Present, bogs become a dominant feature in the northern peatland landscape and CH4 production decreased to reach modern-day levels at about 20 Tg per yr. Northern peatlands have been a key infleunce on global

  14. Environmental and biogeochemical controls on N2 fixation in ombrotrophic peatlands

    Science.gov (United States)

    Zivkovic, T.; Moore, T. R.

    2017-12-01

    Northern peatlands have low atmospheric nitrogen (N) inputs and acquire N mostly via biological, microbially-driven N2-fixation. Little is known about rates and controls on N2-fixation in ombrotrophic bogs. We conducted two studies to test environmental and biogeochemical controls on N2-fixation. First, we used acetylene reduction assay (ARA) calibrated with 15N2 tracer to measure N2-fixation rates in three species of Sphagnum mosses along a hydrological gradient (beaver pond, hollow and hummock in bog margin and in bog) at Mer Bleue bog from June-October 2013 and May - November 2014. We tested the following controls: moisture availability, temperature, and PAR. The largest ARA rates throughout both seasons occurred in the pond in floating Sphagnum cuspidatum mats (50.3 ± 12.9 μmol m-2 d-1 Mean ± SE), which were up to 2.5 times larger than the rates found in the driest hummock site. There was a significant seasonal peak in both years in July and early August that coincided with the peak of the air temperature. In fact, 45% of the variance of N2 fixation rates over the two field seasons was explained by rain events, water table fluctuations and the surface peat temperature (multiple regression analysis, n = 539). Our results highlight the potential impact of climate change, namely negative effects due to potential droughts and positive effect of warming, on N2 fixation patterns in ombrotrophic peatlands. Secondly, we tested stoichiometric controls (Sphagnum tissue N and phosphorous (P) ratio) of N2-fixation. In a controlled environment, we selected eight study sites along a latitudinal gradient from temperate, boreal to subarctic zone in eastern Canada. We found that decreasing N:P ratio corresponded to increasing N2-fixation. N:P explained 65% of the variance in N2-fixation in hollows but only 20% in hummocks. Changes in neither N or P concentration alone explained the increase in N2-fixation better than N:P ratio. We interpret that the difference between

  15. 2000 Years of Grazing History and the Making of the Cretan Mountain Landscape, Greece.

    Science.gov (United States)

    Jouffroy-Bapicot, Isabelle; Vannière, Boris; Iglesias, Virginia; Debret, Maxime; Delarras, Jean-François

    2016-01-01

    Understanding the processes that led to the recent evolution of Mediterranean landscapes is a challenging question that can be addressed with paleoecological data. Located in the White Mountains of Crete, Asi Gonia peat bog constitutes an exceptional 2000-years-long sedimentary archive of environmental change. In this study, we document the making of the White Mountains landscape and assess human impact on ecosystem trajectories. The paleoenvironmental reconstruction is based on high-resolution analyses of sediment, pollen, dung fungal spores and charcoal obtained from a 6-m core collected from the bog. Multiproxy analyses and a robust chronological control have shed light on anthropogenic and natural processes that have driven ecological changes, giving rise to the present-day Mediterranean ecosystem. Our results suggest that sediment accumulation began during the transition from the Hellenistic to the Roman period, likely due to watershed management. The evolution of the peat bog as well as vegetation dynamics in the surrounding area were linked to past climate changes but were driven by human activities, among which breeding was of great importance. Charcoal analysis reveals that fire was largely used for the construction and maintenance of sylvo-agropastoral areas. Pollen data allow the identification of three main vegetation assemblages: 1) evergreen oak forest (before ca. 850 AD), 2) heather maquis (ca. 850 to 1870 AD), 3) phrygana/steppe landscape. Rapid changes between phases in vegetation development are associated with tipping-points in ecosystem dynamics resulting from anthropogenic impact. The modern ecosystem did not get established until the 20th century, and it is characterized by biodiversity loss along with a dramatic drying of the peat bog.

  16. Spatially explicit simulation of peatland hydrology and carbon dioxide exchange

    International Nuclear Information System (INIS)

    Sonnentag, O.

    2008-01-01

    A recent version of the Boreal Ecosystem Productivity Simulator (BEPS) was extended and modified to include northern peatlands. This thesis evaluated the BEPS-TerrainLab using observations made at the Mer Bleue bog located near Ottawa, Ontario, and the Sandhill fen located near Prince Albert, Saskatchewan. The code was revised to represent the multi-layer canopy and processes related to energy, water vapour and carbon dioxide fluxes through remotely-sensed leaf area index (LAI) maps. A quick and reliable method was also developed to determine shrub LAI with the LAI-2000 plant canopy analyzer. A large number of LAI data was collected at the Mer Bleue bog for the development of a new remote sensing-based methodology using multiple end member spectral unmixing to allow for separate tree and shrub LAI mapping in ombrotrophic peatlands. The methodology was also adapted for use in minerotrophic peatlands and their surrounding landscapes. These LAI maps within the BEPS-TerrainLab represented the tree and shrub layers of the Mer Bleue bog and the tree and shrub/sedge layers of the Sandhill fen. The study examined the influence of mesoscale topography (Mer Bleue bog) and macro- and mesoscale topography (Sandhill fen) on wetness, evapotranspiration, and gross primary productivity during the snow-free period of 2004. The results suggested that a peatland type-specific differentiation of macro- and mesoscale topographic effects on hydrology should be included in future peatland ecosystem modelling efforts in order to allow for a more realistic simulation of the soil water balance in peatlands and to reduce uncertainties in carbon dioxide and methane annual fluxes from wetlands

  17. 2000 Years of Grazing History and the Making of the Cretan Mountain Landscape, Greece.

    Directory of Open Access Journals (Sweden)

    Isabelle Jouffroy-Bapicot

    Full Text Available Understanding the processes that led to the recent evolution of Mediterranean landscapes is a challenging question that can be addressed with paleoecological data. Located in the White Mountains of Crete, Asi Gonia peat bog constitutes an exceptional 2000-years-long sedimentary archive of environmental change. In this study, we document the making of the White Mountains landscape and assess human impact on ecosystem trajectories. The paleoenvironmental reconstruction is based on high-resolution analyses of sediment, pollen, dung fungal spores and charcoal obtained from a 6-m core collected from the bog. Multiproxy analyses and a robust chronological control have shed light on anthropogenic and natural processes that have driven ecological changes, giving rise to the present-day Mediterranean ecosystem. Our results suggest that sediment accumulation began during the transition from the Hellenistic to the Roman period, likely due to watershed management. The evolution of the peat bog as well as vegetation dynamics in the surrounding area were linked to past climate changes but were driven by human activities, among which breeding was of great importance. Charcoal analysis reveals that fire was largely used for the construction and maintenance of sylvo-agropastoral areas. Pollen data allow the identification of three main vegetation assemblages: 1 evergreen oak forest (before ca. 850 AD, 2 heather maquis (ca. 850 to 1870 AD, 3 phrygana/steppe landscape. Rapid changes between phases in vegetation development are associated with tipping-points in ecosystem dynamics resulting from anthropogenic impact. The modern ecosystem did not get established until the 20th century, and it is characterized by biodiversity loss along with a dramatic drying of the peat bog.

  18. Spatially explicit simulation of peatland hydrology and carbon dioxide exchange

    Energy Technology Data Exchange (ETDEWEB)

    Sonnentag, O.

    2008-08-01

    A recent version of the Boreal Ecosystem Productivity Simulator (BEPS) was extended and modified to include northern peatlands. This thesis evaluated the BEPS-TerrainLab using observations made at the Mer Bleue bog located near Ottawa, Ontario, and the Sandhill fen located near Prince Albert, Saskatchewan. The code was revised to represent the multi-layer canopy and processes related to energy, water vapour and carbon dioxide fluxes through remotely-sensed leaf area index (LAI) maps. A quick and reliable method was also developed to determine shrub LAI with the LAI-2000 plant canopy analyzer. A large number of LAI data was collected at the Mer Bleue bog for the development of a new remote sensing-based methodology using multiple end member spectral unmixing to allow for separate tree and shrub LAI mapping in ombrotrophic peatlands. The methodology was also adapted for use in minerotrophic peatlands and their surrounding landscapes. These LAI maps within the BEPS-TerrainLab represented the tree and shrub layers of the Mer Bleue bog and the tree and shrub/sedge layers of the Sandhill fen. The study examined the influence of mesoscale topography (Mer Bleue bog) and macro- and mesoscale topography (Sandhill fen) on wetness, evapotranspiration, and gross primary productivity during the snow-free period of 2004. The results suggested that a peatland type-specific differentiation of macro- and mesoscale topographic effects on hydrology should be included in future peatland ecosystem modelling efforts in order to allow for a more realistic simulation of the soil water balance in peatlands and to reduce uncertainties in carbon dioxide and methane annual fluxes from wetlands.

  19. Abundance, diversity and depth distribution of Planctomycetes in northern Sphagnum-dominated wetlands

    Directory of Open Access Journals (Sweden)

    Svetlana N. Dedysh

    2012-01-01

    Full Text Available Members of the bacterial phylum Planctomycetes inhabit various aquatic and terrestrial environments. In this study, fluorescence in situ hybridization (FISH was applied to assess the abundance and depth distribution of these bacteria in nine different Sphagnum-dominated wetlands of Northern Russia. Planctomycetes were most abundant in the oxic part of peat bog profiles. The respective cell numbers were in the range 1.1-6.7×107 cells per gram of wet peat, comprising 2 to 14% of total bacterial cells and displaying linear correlation to the peat water pH. Most peatland sites showed a sharp decline of planctomycete abundance with depth, while in two particular sites this decline was followed by a second population maximum in an anoxic part of the bog profile. Oxic peat layers were dominated by representatives of the Isosphaera-Singulisphaera group, while anoxic part of the bog profile was inhabited mostly by Zavarzinella- and Pirellula-like planctomycetes. Phylogenetically related bacteria of the candidate division OP3 were detected in both oxic and anoxic peat with cell densities of 0.6-4.6×106 cells per gram of wet peat.

  20. In vitro decomposition of Sphagnum by some microfungi resembles white rot of wood.

    Science.gov (United States)

    Rice, Adrianne V; Tsuneda, Akihiko; Currah, Randolph S

    2006-06-01

    The abilities of some ascomycetes (Myxotrichaceae) from a Sphagnum bog in Alberta to degrade cellulose, phenolics, and Sphagnum tissue were compared with those of two basidiomycetes. Most Myxotrichaceae degraded cellulose and tannic acid, and removed cell-wall components simultaneously from Sphagnum tissues, whereas the basidiomycetes degraded cellulose and insoluble phenolics, and preferentially removed the polyphenolic matrix from Sphagnum cell walls. Mass losses from Sphagnum varied from up to 50% for some ascomycetes to a maximum of 35% for the basidiomycetes. The decomposition of Sphagnum by the Myxotrichaceae was analogous to the white rot of wood and indicates that these fungi have the potential to cause significant mineralization of carbon in bogs.

  1. Tekster til organisationsanalyse

    DEFF Research Database (Denmark)

    Bogen samler klassiske og nyere tekster om organisationer. Forfattere som Weber, Taylor, March, Schein, Mintzberg og Weick indgår mange steder som fast pensum på organisationsfag, og her er de samlet i een bog. Tilsammen tilbyder teksterne afsæt for analyser af en lang række aspekter af organisat......Bogen samler klassiske og nyere tekster om organisationer. Forfattere som Weber, Taylor, March, Schein, Mintzberg og Weick indgår mange steder som fast pensum på organisationsfag, og her er de samlet i een bog. Tilsammen tilbyder teksterne afsæt for analyser af en lang række aspekter af...

  2. "A Scrapbook of You + Me"

    DEFF Research Database (Denmark)

    Tanderup, Sara

    2017-01-01

    Artiklen læser det eksperimentende bog-værk S. (2013), af Doug Dorst og J.J. Abrams, som en refleksion over, og et udtryk for den trykte romans forandrede status i en digital tidsalder. Som en eksperimenterende roman med gulnede sider og håndskrift i marginen synes S. at reflektere en materiel ve...... perspektiver fra bl.a. N. Katherine Hayles, Bill Brown og Henry Jenkins, påpeger jeg således en spænding i S. Den dyrker en nostalgisk bog-æstetik, samtidig med, at den omfavner en moderne mediekultur, hvor litteraturen også forgår uden for bogen, mellem medier....

  3. Small scale soil carbon and moisture gradients in a drained peat bog grassland and their influence on CO2, CH4 and N2O fluxes

    Science.gov (United States)

    Leiber-Sauheitl, K.; Fuß, R.; Freibauer, A.

    2012-04-01

    Due to the UNFCCC report requirements of each country on the emissions of greenhouse gases from key sources the joint research project "Organic Soils" was established in Germany. The project's objective is to improve the data set on greenhousegas emissions from organic soils in Germany. Within 12 German Project Catchments emissions from different types of organic soils, e.g. under different land uses and hydrological conditions, are measured. At the location "Großes Moor" near Gifhorn (Lower Saxony) the effects of small-scale soil organic carbon and groundwater level gradients on the GHG fluxes (CO2, CH4 and N2O) are quantified. The study area is located within a former peat bog altered by drainage and peat cutting, which is currently grassland under extensive agricultural use. The focus of the study is on the acquisition of CO2, CH4 and N2O fluxes on six sites via manual closed chambers. In order to calculate the annual CO2 exchange rate, values are interpolated on a 0.5 hour scale between measurement campaigns. In combination with continually logged meteorological parameters, such as the photosynthetic active radiation as well as air and soil temperatures, we calculate the daily CO2 ecosystem exchange of the different sites. During the 2011 campaign, CO2 was determined as the most important greenhouse gas. The groundwater table was the dominant variable influencing gas emissions. Another important factor was the vegetation composition. In detail, highest CO2 emissions occurred with a water table of 40-50 cm below ground level, temperatures above 10°C and low plant biomass amounts. Due to the more complex formation of N2O by a number of processes, each being promoted by different soil conditions, the measurement of N2O fluxes in the field was complemented by a laboratory experiment. In this, the use of stable isotope tracer techniques enabled us to quantify the contribution of single biochemical pathways to the overall formation of N2O under controlled

  4. The geology, botany and chemistry of selected peat-forming environments from temperate and tropical latitudes

    Science.gov (United States)

    Cameron, C.C.; Esterle, J.S.; Palmer, C.A.

    1989-01-01

    Peat has been studied in several geologic settings: (1) glaciated terrain in cold temperate Maine and Minnesota, U.S.A.; (2) an island in the Atlantic Ocean off the coast of Maine, where sea level is rising; (3) the warm temperate U.S. Atlantic and Gulf Coastal Plains, where sea level has changed often; and (4) the tropical coast of Sarawak, Malaysia, and the tropical delta of the Batang Hari River, Sumatra, Indonesia. Most of these deposits are domed (ombrotrophic or partly ombrotrophic) bogs in which peat accumulation continued above the surface of the surrounding soil. However, the bogs of the U.S. Atlantic and Gulf Coastal Plains are comparatively not as domed, and many have almost level surfaces. In some bogs, aquatic or semi-aquatic plant materials accumulated, replaced water in the depressions, and formed a surface on which marsh or swamp vegetation could subsequently live, die, and accumulate. In others, the plant materials accumulated initially on level silt or sand surfaces supporting marshes or swamps. As the peat dome formed, plants growing on it changed from luxuriant ones near the base of the dome, where nutrients were brought into the bog by surface and ground water, to stunted ones at the top of the dome, where the raised bogs are fed by nutrient-poor precipitation. The physical and chemical changes that take place in the sequence of environments from the pond stage of deposit development, through the grassy marsh stage, through the forested swamp stage, and finally through the heath dome stage can be measured in terms of acidity and ash, volatile matter, carbon, hydrogen, nitrogen, sulfur and oxygen contents, as well as in the kind and distribution of trace elements. The organic and inorganic contents of the deposits relate to geomorphology, and geomorphology relates to their settings. As models of coal formation, some domed peat deposits may help in solving problems of distribution and character of ancient coal beds. But clearly not all peat

  5. High soil solution carbon and nitrogen concentrations in a drained Atlantic bog are reduced to natural levels by 10 years of rewetting

    Science.gov (United States)

    Frank, S.; Tiemeyer, B.; Gelbrecht, J.; Freibauer, A.

    2014-04-01

    Anthropogenic drainage of peatlands releases additional greenhouse gases to the atmosphere, and dissolved carbon (C) and nutrients to downstream ecosystems. Rewetting drained peatlands offers a possibility to reduce nitrogen (N) and C losses. In this study, we investigate the impact of drainage and rewetting on the cycling of dissolved C and N as well as on dissolved gases, over a period of 1 year and a period of 4 months. We chose four sites within one Atlantic bog complex: a near-natural site, two drained grasslands with different mean groundwater levels and a former peat cutting area rewetted 10 years ago. Our results clearly indicate that long-term drainage has increased the concentrations of dissolved organic carbon (DOC), ammonium, nitrate and dissolved organic nitrogen (DON) compared to the near-natural site. DON and ammonium contributed the most to the total dissolved nitrogen. Nitrate concentrations below the mean groundwater table were negligible. The concentrations of DOC and N species increased with drainage depth. In the deeply-drained grassland, with a mean annual water table of 45 cm below surface, DOC concentrations were twice as high as in the partially rewetted grassland with a mean annual water table of 28 cm below surface. The deeply drained grassland had some of the highest-ever observed DOC concentrations of 195.8 ± 77.3 mg L-1 with maximum values of >400 mg L-1. In general, dissolved organic matter (DOM) at the drained sites was enriched in aromatic moieties and showed a higher degradation status (lower DOC to DON ratio) compared to the near-natural site. At the drained sites, the C to N ratios of the uppermost peat layer were the same as of DOM in the peat profile. This suggests that the uppermost degraded peat layer is the main source of DOM. Nearly constant DOM quality through the profile furthermore indicated that DOM moving downwards through the drained sites remained largely biogeochemically unchanged. Unlike DOM concentration, DOM

  6. Small-scale variability in peatland pore-water biogeochemistry, Hudson Bay Lowland, Canada.

    Science.gov (United States)

    Ulanowski, T A; Branfireun, B A

    2013-06-01

    The Hudson Bay Lowland (HBL) of northern Ontario, Manitoba and Quebec, Canada is the second largest contiguous peatland complex in the world, currently containing more than half of Canada's soil carbon. Recent concerns about the ecohydrological impacts to these large northern peatlands resulting from climate change and resource extraction have catalyzed a resurgence in scientific research into this ecologically important region. However, the sheer size, heterogeneity and elaborate landscape arrangements of this ecosystem raise important questions concerning representative sampling of environmental media for chemical or physical characterization. To begin to quantify such variability, this study assessed the small-scale spatial (1m) and short temporal (21 day) variability of surface pore-water biogeochemistry (pH, dissolved organic carbon, and major ions) in a Sphagnum spp.-dominated, ombrotrophic raised bog, and a Carex spp.-dominated intermediate fen in the HBL. In general, pore-water pH and concentrations of dissolved solutes were similar to previously reported literature values from this region. However, systematic sampling revealed consistent statistically significant differences in pore-water chemistries between the bog and fen peatland types, and large within-site spatiotemporal variability. We found that microtopography in the bog was associated with consistent differences in most biogeochemical variables. Temporal changes in dissolved solute chemistry, particularly base cations (Na(+), Ca(2+) and Mg(2+)), were statistically significant in the intermediate fen, likely a result of a dynamic connection between surficial waters and mineral-rich deep groundwater. In both the bog and fen, concentrations of SO4(2-) showed considerable spatial variability, and a significant decrease in concentrations over the study period. The observed variability in peatland pore-water biogeochemistry over such small spatial and temporal scales suggests that under-sampling in

  7. Peatland Microbial Communities and Decomposition Processes in the James Bay Lowlands, Canada

    Science.gov (United States)

    Preston, Michael D.; Smemo, Kurt A.; McLaughlin, James W.; Basiliko, Nathan

    2012-01-01

    Northern peatlands are a large repository of atmospheric carbon due to an imbalance between primary production by plants and microbial decomposition. The James Bay Lowlands (JBL) of northern Ontario are a large peatland-complex but remain relatively unstudied. Climate change models predict the region will experience warmer and drier conditions, potentially altering plant community composition, and shifting the region from a long-term carbon sink to a source. We collected a peat core from two geographically separated (ca. 200 km) ombrotrophic peatlands (Victor and Kinoje Bogs) and one minerotrophic peatland (Victor Fen) located near Victor Bog within the JBL. We characterized (i) archaeal, bacterial, and fungal community structure with terminal restriction fragment length polymorphism of ribosomal DNA, (ii) estimated microbial activity using community level physiological profiling and extracellular enzymes activities, and (iii) the aeration and temperature dependence of carbon mineralization at three depths (0–10, 50–60, and 100–110 cm) from each site. Similar dominant microbial taxa were observed at all three peatlands despite differences in nutrient content and substrate quality. In contrast, we observed differences in basal respiration, enzyme activity, and the magnitude of substrate utilization, which were all generally higher at Victor Fen and similar between the two bogs. However, there was no preferential mineralization of carbon substrates between the bogs and fens. Microbial community composition did not correlate with measures of microbial activity but pH was a strong predictor of activity across all sites and depths. Increased peat temperature and aeration stimulated CO2 production but this did not correlate with a change in enzyme activities. Potential microbial activity in the JBL appears to be influenced by the quality of the peat substrate and the presence of microbial inhibitors, which suggests the existing peat substrate will have a large

  8. Three novel herpesviruses of endangered Clemmys and Glyptemys turtles.

    Science.gov (United States)

    Ossiboff, Robert J; Raphael, Bonnie L; Ammazzalorso, Alyssa D; Seimon, Tracie A; Newton, Alisa L; Chang, Tylis Y; Zarate, Brian; Whitlock, Alison L; McAloose, Denise

    2015-01-01

    The rich diversity of the world's reptiles is at risk due to significant population declines of broad taxonomic and geographic scope. Significant factors attributed to these declines include habitat loss, pollution, unsustainable collection and infectious disease. To investigate the presence and significance of a potential pathogen on populations of critically endangered bog turtles (Glyptemys muhlenbergii) as well sympatric endangered wood (G. insculpta) and endangered spotted (Clemmys guttata) turtles in the northeastern United States, choanal and cloacal swabs collected from 230 turtles from 19 sites in 5 states were screened for herpesvirus by polymerase chain reaction. We found a high incidence of herpesvirus infection in bog turtles (51.5%; 105/204) and smaller numbers of positive wood (5) and spotted (1) turtles. Sequence and phylogenetic analysis revealed three previously uncharacterized alphaherpesviruses. Glyptemys herpesvirus 1 was the predominant herpesvirus detected and was found exclusively in bog turtles in all states sampled. Glyptemys herpesvirus 2 was found only in wood turtles. Emydid herpesvirus 2 was found in a small number of bog turtles and a single spotted turtle from one state. Based on these findings, Glyptemys herpesvirus 1 appears to be a common infection in the study population, whereas Glyptemys herpesvirus 2 and Emydid herpesvirus 2 were not as frequently detected. Emydid herpesvirus 2 was the only virus detected in more than one species. Herpesviruses are most often associated with subclinical or mild infections in their natural hosts, and no sampled turtles showed overt signs of disease at sampling. However, infection of host-adapted viruses in closely related species can result in significant disease. The pathogenic potential of these viruses, particularly Emydid herpesvirus 2, in sympatric chelonians warrants additional study in order to better understand the relationship of these viruses with their endangered hosts.

  9. Test results from the GA technologies engineering-scale off-gas treatment system

    International Nuclear Information System (INIS)

    Jensen, D.D.; Olguin, L.J.; Wilbourn, R.G.

    1984-06-01

    One method for reducing the volume of HTGR fuel prior to reprocessing or spent fuel storage is to crush and burn the graphite fuel elements. The burner off-gas (BOG) contains radioactive components, principally H-3, C-14, Kr-85, I-129, and Rn-220, as well as chemical forms such as CO 2 , CO, O 2 , and SO 2 . The BOG system employs components designed to remove these constitutents. Test results are reported for the iodine and SO 2 adsorbers and the CO/HT oxidizer. Silver-based iodine adsorbents were found to catalyze the premature conversion of CO to CO 2 . Subsequent tests showed that iodine removal could not be performed downstream of the CO/HT oxidizer since iodine in the BOG system rapidly deactivated the Pt-coated alumina CO catalyst. Lead-exchanged zeolite (PbX) was found to be an acceptable alternative for removing iodine from BOG without CO conversion. Intermittent and steady-state tests of the pilot-plant SO 2 removal unit containing sodium-exchanged zeolite (NaX) demonstrated that decontamination factors greater than or equal to 100 could be maintained for up to 50 h. In a reprocessing flowsheet, the solid product from the burners is dissolved in nitric or Thorex acid. The dissolver off-gas (DOG) contains radioactive components H-3, Kr-85, I-129, Rn-220 plus chemical forms such as nitrogen oxides (NO/sub x/). In the pilot-scale system at GA, iodine is removed from the DOG by adsorption. Tests of iodine removal have been conducted using either silver-exchanged mordenite (AgZ) or AgNO 3 -impregnated silica gel (AC-6120). Although each sorbent performed well in the presence of NO/sub x/, the silica gel adsorbent proved more efficient in silver utilization and, thus, more cost effective

  10. Three Novel Herpesviruses of Endangered Clemmys and Glyptemys Turtles

    Science.gov (United States)

    Ossiboff, Robert J.; Raphael, Bonnie L.; Ammazzalorso, Alyssa D.; Seimon, Tracie A.; Newton, Alisa L.; Chang, Tylis Y.; Zarate, Brian; Whitlock, Alison L.; McAloose, Denise

    2015-01-01

    The rich diversity of the world’s reptiles is at risk due to significant population declines of broad taxonomic and geographic scope. Significant factors attributed to these declines include habitat loss, pollution, unsustainable collection and infectious disease. To investigate the presence and significance of a potential pathogen on populations of critically endangered bog turtles (Glyptemys muhlenbergii) as well sympatric endangered wood (G. insculpta) and endangered spotted (Clemmys guttata) turtles in the northeastern United States, choanal and cloacal swabs collected from 230 turtles from 19 sites in 5 states were screened for herpesvirus by polymerase chain reaction. We found a high incidence of herpesvirus infection in bog turtles (51.5%; 105/204) and smaller numbers of positive wood (5) and spotted (1) turtles. Sequence and phylogenetic analysis revealed three previously uncharacterized alphaherpesviruses. Glyptemys herpesvirus 1 was the predominant herpesvirus detected and was found exclusively in bog turtles in all states sampled. Glyptemys herpesvirus 2 was found only in wood turtles. Emydid herpesvirus 2 was found in a small number of bog turtles and a single spotted turtle from one state. Based on these findings, Glyptemys herpesvirus 1 appears to be a common infection in the study population, whereas Glyptemys herpesvirus 2 and Emydid herpesvirus 2 were not as frequently detected. Emydid herpesvirus 2 was the only virus detected in more than one species. Herpesviruses are most often associated with subclinical or mild infections in their natural hosts, and no sampled turtles showed overt signs of disease at sampling. However, infection of host-adapted viruses in closely related species can result in significant disease. The pathogenic potential of these viruses, particularly Emydid herpesvirus 2, in sympatric chelonians warrants additional study in order to better understand the relationship of these viruses with their endangered hosts. PMID

  11. Three novel herpesviruses of endangered Clemmys and Glyptemys turtles.

    Directory of Open Access Journals (Sweden)

    Robert J Ossiboff

    Full Text Available The rich diversity of the world's reptiles is at risk due to significant population declines of broad taxonomic and geographic scope. Significant factors attributed to these declines include habitat loss, pollution, unsustainable collection and infectious disease. To investigate the presence and significance of a potential pathogen on populations of critically endangered bog turtles (Glyptemys muhlenbergii as well sympatric endangered wood (G. insculpta and endangered spotted (Clemmys guttata turtles in the northeastern United States, choanal and cloacal swabs collected from 230 turtles from 19 sites in 5 states were screened for herpesvirus by polymerase chain reaction. We found a high incidence of herpesvirus infection in bog turtles (51.5%; 105/204 and smaller numbers of positive wood (5 and spotted (1 turtles. Sequence and phylogenetic analysis revealed three previously uncharacterized alphaherpesviruses. Glyptemys herpesvirus 1 was the predominant herpesvirus detected and was found exclusively in bog turtles in all states sampled. Glyptemys herpesvirus 2 was found only in wood turtles. Emydid herpesvirus 2 was found in a small number of bog turtles and a single spotted turtle from one state. Based on these findings, Glyptemys herpesvirus 1 appears to be a common infection in the study population, whereas Glyptemys herpesvirus 2 and Emydid herpesvirus 2 were not as frequently detected. Emydid herpesvirus 2 was the only virus detected in more than one species. Herpesviruses are most often associated with subclinical or mild infections in their natural hosts, and no sampled turtles showed overt signs of disease at sampling. However, infection of host-adapted viruses in closely related species can result in significant disease. The pathogenic potential of these viruses, particularly Emydid herpesvirus 2, in sympatric chelonians warrants additional study in order to better understand the relationship of these viruses with their endangered hosts.

  12. Modulation of Fire Regimes by Vegetation and Site Type in Southwestern Patagonia Since 13 ka

    Directory of Open Access Journals (Sweden)

    Patricio I. Moreno

    2018-04-01

    Full Text Available The degree to which vegetation and site type have influenced fire regimes through the Holocene has not been investigated in detail in the temperate ecosystems of southern Patagonia. Here we present a first attempt using a paired-basin approach to study the evolution of fire regimes in sectors dominated by humid Nothofagus forests and the xeric Patagonian steppe in the Magallanes region of Chilean Patagonia (51°S. We analyzed sediment cores from two small lakes and a bog located within the same climate zone on opposite sides of the forest-steppe ecotone, ~28 km apart. The position of this biological boundary east of the Andes is controlled by the strength and position of the southern westerly winds, which constitute the sole source of precipitation throughout western Patagonia. Our results indicate that fires have occurred in the study region repeated times over the last ~13,000 years at bi- and tridecadal timescales. Sectors currently dominated by Patagonian steppe feature high frequency and low magnitude of local fires, and vice versa in humid forests. Climate-driven expansion of Nothofagus scrubland/woodland into steppe environments over the last ~4,200 years increased the magnitude and lowered the frequency of fire events, culminating with peak Nothofagus abundance, fire magnitude and frequency during the last millennium. We also detect divergences between lake-based vs. bog-based paleofire histories among paired sites located within the Patagonian steppe, ~12 km apart, which we attribute to local burning of the bog at times of lowered water table. This divergence suggests to us that bog-based vegetation and fire histories exacerbate a local, azonal, signal blurring extra-local or regional regimes, thus accounting for some discrepancies in the Quaternary paleovegetation/paleoclimate literature of southern Patagonia.

  13. German mires - Utilisation and protection

    International Nuclear Information System (INIS)

    Roderfeld, H.

    1996-01-01

    Mires in Germany are mainly used for agriculture. Peat mining is important regionally, but forest utilisation less so. Twenty years ago in the former West Germany, the first steps from peatland utilisation to peatland protection were taken. Bog protection programmes were developed first. Nowadays research directed to fen protection has begun, prompted by the decreasing importance of agriculture in Central Europe and an increasing environmental awareness. The situation regarding mire protection in Germany is presented for each Federal State individually. A rough estimate suggests 45 000 ha of protected bogs and 25 000 ha of protected fens. These areas include natural and semi-natural mires as well as rewetted mires. (30 refs.)

  14. Potassium effect on cesium 137 behaviour in natural waters of contaminated regions (Belarus)

    International Nuclear Information System (INIS)

    Kudel'skij, A.V.; Pashkevich, V.I.; Ovsyannikova, S.V.; Petrovich, A.A.; Smit, D.T.

    1998-01-01

    Very close relationships between cesium 137 activity of water objects (soil solutions, bog and lake water) and their stable potassium contents have been revealed in the contaminated area in south-eastern Belarus. It was revealed the increase of cesium 137 activity in soil solutions and bog ecosystems proportionally with the increase of potassium content. The exponential dependence of cesium 137 activity of fish production was similar to reverse. The coefficient of cesium 137 accumulation in plants was estimated to be reverse connected with the potassium content in soils. So an universal character of these relations and their specificity are of interest when elaborating countermeasures for reducing population dose loads due to cesium 137 water migration

  15. Decreasing concentrations of metals in Sphagnum mosses in ombrotrophic mires of the Sudety mountains (SW Poland) since late 1980s.

    Science.gov (United States)

    Wojtuń, Bronisław; Samecka-Cymerman, Aleksandra; Kolon, Krzysztof; Kempers, Alexander J

    2013-06-01

    In this investigation we focus on the evaluation of changes in metal pollution between 1986 until 2011 by Sphagnum species as bioindicators in 100 km part of the Sudety mountains influenced by the former Black Triangle Region. Concentrations of Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb and Zn were measured in various Sphagnum species all from ombrotrophic bogs in the Sudety mountains (SW Poland). The tested hypothesis was that overall improvements in pollution control in the former Black Triangle Region between 1986 until recent reduced the amount of metals deposited and accumulated by these plants. Concentrations of Cd, Cr, Cu, Fe, Pb and Zn in Sphagnum species were very high in 1986 indicating a heavy pollution of the examined bogs in this period, and significantly higher than in samples collected in 2011. The PCCA ordination showed the similar pattern in all bogs. In 2011 concentration of the Co was significantly higher in hollow species and concentration of Mn was significantly higher in those from hummocks. Differences between hollow/hummock sites were more important than species-specific abilities of Sphagnum mosses to accumulate metals. Species from hollows were better bioindicators of Co and those from hummocks were better bioindicators of Mn pollution. Copyright © 2012 Elsevier Ltd. All rights reserved.

  16. Simulation of the hydrogeologic effects of oil-shale mining on the neighbouring wetland water balance: case study in north-eastern Estonia

    Science.gov (United States)

    Marandi, Andres; Karro, Enn; Polikarpus, Maile; Jõeleht, Argo; Kohv, Marko; Hang, Tiit; Hiiemaa, Helen

    2013-11-01

    The water balance of wetlands plays an integral role in their function. Developments adjacent to wetlands can affect their water balance through impacts on groundwater flow and increased discharge in the area, and they can cause lowering of the wetland water table. A 430 km2 area was selected for groundwater modelling to asses the effect of underground mining on the water balance of wetlands in north-eastern Estonia. A nature conservation area (encompassing Selisoo bog) is within 3 km of an underground oil-shale mine. Two future mining scenarios with different areal extents of mining were modeled and compared to the present situation. Results show that the vertical hydraulic conductivity of the subsurface is of critical importance to potential wetland dewatering as a result of mining. Significant impact on the Selisoo bog water balance will be caused by the approaching mine but there will be only minor additional impacts from mining directly below the bog. The major impact will arise before that stage, when the underground mine extension reaches the border of the nature conservation area; since the restriction of activities in this area relates to the ground surface, the conservation area’s border is not sufficiently protective in relation to underground development.

  17. Multiproxy records of Holocene climate and glacier variability from sediment cores in the Cordillera Vilcabamba of southern Peru

    Science.gov (United States)

    Schweinsberg, A. D.; Licciardi, J. M.; Rodbell, D. T.; Stansell, N.; Tapia, P. M.

    2012-12-01

    Sediments contained in glacier-fed lakes and bogs provide continuous high-resolution records of glacial activity, and preserve multiproxy evidence of Holocene climate change. Tropical glacier fluctuations offer critical insight on regional paleoclimatic trends and controls, however, continuous sediment records of past tropical climates are limited. Recent cosmogenic 10Be surface exposure ages of moraine sequences in the Cordillera Vilcabamba of southern Peru (13°20'S latitude) reveal a glacial culmination during the early Holocene and a less extensive glaciation coincident with the Little Ice Age of the Northern Hemisphere. Here we supplement the existing 10Be moraine chronology with the first continuous records of multiproxy climate data in this mountain range from sediment cores recovered from bogs in direct stratigraphic contact with 10Be-dated moraines. Radiocarbon-dated sedimentological changes in a 2-meter long bog core reveal that the Holocene is characterized by alternating inorganic and organic-rich laminae, suggesting high-frequency climatic variability. Carbon measurements, bulk density, and bulk sedimentation rates are used to derive a record of clastic sediment flux that serves as a proxy indicator of former glacier activity. Preliminary analyses of the bog core reveal approximately 70 diatom taxa that indicate both rheophilic and lentic environments. Initial results show a general decrease in magnetic susceptibility and clastic flux throughout the early to mid-Holocene, which suggests an interval of deglaciation. An episode of high clastic flux from 3.8 to 2.0 ka may reflect a late Holocene glacial readvance. Volcanic glass fragments and an anomalous peak in magnetic susceptibility may correspond to the historical 1600 AD eruption of Huaynaputina. Ten new bog and lake sediment cores were collected during the 2012 field expedition and analytical measurements are underway. Ongoing efforts are focused on analyzing diatom assemblage data, developing

  18. O sallingmo'l

    DEFF Research Database (Denmark)

    Hansen, Inger Schoonderbeek

    2005-01-01

    Anmeldelsen har til formål kort at beskrive Jens Ejsings nyeste bog, som beskriver sallingmålets grammatik meget detaljeret. Anmeldelsen er informativ snarere end kritisk. Udgivelsesdato: december...

  19. Bedste bog om Balkans beskidte krig

    DEFF Research Database (Denmark)

    Lund, Joachim

    2018-01-01

    Anmeldelse af: "Vi troede ikke, det kunne ske her. Jugoslaviens sammenbrud 1991-1999" af Christian Axboe Nielsen. Kristeligt Dagblads Forlag, 2018. 410 sider......Anmeldelse af: "Vi troede ikke, det kunne ske her. Jugoslaviens sammenbrud 1991-1999" af Christian Axboe Nielsen. Kristeligt Dagblads Forlag, 2018. 410 sider...

  20. Bog Stvoritelj u djelu Charlesa Darwina

    OpenAIRE

    Balabanić, Josip

    2009-01-01

    U ovome članku traži se odgovor na pitanje zašto u djelu Charlesa Darwina (1809-1882) ima iznenađujuća količina izravna teološkog sadržaja i zašto je, premda pristaša znanstvenog redukcionizma, u svoja kapitalna djela Postanak vrsta (1859) i Podrijetlo čovjeka (1871) unio egzistencijalnu dimenziju vlastita religioznog stajališta o Bogu kao stvoritelju putem sekundarnih uzroka (tj. prirodnih zakona). Na temelju njegovih izjava i navoda iz Autobiografje izvodi se zaključak kako Darwin Stvoritel...

  1. Bog rodom iz detstva / Jelena Skulskaja

    Index Scriptorium Estoniae

    Skulskaja, Jelena, 1950-

    2007-01-01

    Eldar Rjazanovi eluloofilm muinasjutuvestja Hans Christian Anderseni elust "Andersen. Elu ilma armastuseta" ("Andersen. Zhizn bez ljubvi"): stsenarist Irakli Kvirikadze : operaatorid Jevgeni Guslinski ja Vadim Alissov : helilooja Aleksei Rõbnikov : nimiosas Vanja Haratjan, Stanislav Rjadinski, Sergei Migitsko

  2. Insect biodiversity of boreal peat bogs

    Czech Academy of Sciences Publication Activity Database

    Spitzer, Karel; Danks, H. V.

    2006-01-01

    Roč. 51, - (2006), s. 137-161 ISSN 0066-4170 R&D Projects: GA ČR(CZ) GA206/97/0077; GA AV ČR(CZ) IBS5007015 Institutional research plan: CEZ:AV0Z50070508 Keywords : peatlands * tyrphobiontic insects * conservation Subject RIV: EH - Ecology, Behaviour Impact factor: 8.714, year: 2006

  3. Late-Holocene hydroclimate and atmospheric circulation variability in southern Patagonia: insights from triple stable isotopes (δ18O, δ13C, δD) of peat bog Sphagnum moss

    Science.gov (United States)

    Xia, Z.; Yu, Z.; Zheng, Y.; Loisel, J.; Huang, Y.

    2017-12-01

    The Southern Hemisphere Westerly Winds (SHWWs) exert important influences on regional and global climates, but their long-term behaviors and dynamics are still poorly understood but critical for projecting future changes. Here we present a 5,500-year record from a Sphagnum-dominated peat bog located on the lee side of the Andes at 54.2 °S in southern Patagonia—based on plant macrofossils, Sphagnum cellulose δ18O and δ13C, and lipid δD data—to document and understand the variability in hydroclimate and atmospheric circulation. There is a striking negative correlation between cellulose δ18O and the Southern Annular Mode (SAM) index over the last millennium; particularly the 2.5‰ negative shift of δ18O is concurrent with the observed positive trend in the SAM over the recent decades. The interval of Medieval Climate Anomaly (MCA, 850-600 yr BP) is characterized by a 2.5‰ negative shift of δ18O and low δ13C values, while the Little Ice Age (LIA, 500-300 yr BP) is characterized by a 2.5‰ positive shift of δ18O and high δ13C values. Furthermore, we find the largest negative shift of δ18O ( 3‰) at 2,300 yr BP, suggesting a significantly positive shift in the SAM. We interpret high Sphagnum abundance and high cellulose δ13C values to reflect great moss moisture conditions, while cellulose δ18O variations primarily reflect moisture sources and atmospheric circulation. During the positive phase of SAM (e.g., the MCA and recent decades), strengthened SHWWs enhance the rain-shadow effect, resulting in dry climate and 18O-depleted precipitation (low δ18O values) in the study region. During the negative phase of SAM (e.g., the LIA), weakened SHWWs reduce rain-shadow effect, resulting in wet climate and high δ18O values caused by increases in moisture contributions from the southerly and easterly flows that do not experience strong Rayleigh distillation process during air mass transports. Furthermore, coupling cellulose δ18O and lipid δD enables

  4. 33 CFR 332.6 - Monitoring.

    Science.gov (United States)

    2010-07-01

    ...., forested wetlands, bogs). Following project implementation, the district engineer may reduce or waive the... performance standards, and may include plans (such as as-built plans), maps, and photographs to illustrate...

  5. 40 CFR 230.96 - Monitoring.

    Science.gov (United States)

    2010-07-01

    ... required for aquatic resources with slow development rates (e.g., forested wetlands, bogs). Following..., and may include plans (such as as-built plans), maps, and photographs to illustrate site conditions...

  6. Investigation of detergent effects on the solution structure of spinach Light Harvesting Complex II

    Energy Technology Data Exchange (ETDEWEB)

    Cardoso, Mateus B; Smolensky, Dmitriy; Heller, William T; O' Neill, Hugh, E-mail: hellerwt@ornl.gov, E-mail: oneillhm@ornl.gov [Center for Structural Molecular Biology, Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States)

    2010-11-01

    The properties of spinach light harvesting complex II (LHC II), stabilized in the detergents Triton X-100 (TX100) and n-Octyl-{beta}-D-Glucoside (BOG), were investigated by small-angle neutron scattering (SANS). The LHC II-BOG scattering curve overlaid well with the theoretical scattering curve generated from the crystal structure of LHC II indicating that the protein preparation was in its native functional state. On the other hand, the simulated LHC II curve deviated significantly from the LHC II-TX100 experimental data. Analysis by circular dichroism spectroscopy supported the SANS analysis and showed that LHC II-TX100 is inactivated. This investigation has implications for extracting and stabilizing photosynthetic membrane proteins for the development of biohybrid photoconversion devices.

  7. Short-term standard litter decomposition across three different ecosystems in middle taiga zone of West Siberia

    Science.gov (United States)

    Filippova, Nina V.; Glagolev, Mikhail V.

    2018-03-01

    The method of standard litter (tea) decomposition was implemented to compare decomposition rate constants (k) between different peatland ecosystems and coniferous forests in the middle taiga zone of West Siberia (near Khanty-Mansiysk). The standard protocol of TeaComposition initiative was used to make the data usable for comparisons among different sites and zonobiomes worldwide. This article sums up the results of short-term decomposition (3 months) on the local scale. The values of decomposition rate constants differed significantly between three ecosystem types: it was higher in forest compared to bogs, and treed bogs had lower decomposition constant compared to Sphagnum lawns. In general, the decomposition rate constants were close to ones reported earlier for similar climatic conditions and habitats.

  8. Accumulation of organic carbon over the past 150 years in five freshwater peatlands in western and central Europe

    International Nuclear Information System (INIS)

    Novak, Martin; Brizova, Eva; Adamova, Marie; Erbanova, Lucie; Bottrell, Simon H.

    2008-01-01

    Under predicted scenarios of global climate change, peatlands may become a net source of greenhouse gases which will accelerate warming of the atmosphere. Comparative studies of peat bogs along present climatic gradients may provide an insight into the future response of boreal and subarctic peatlands to changing temperature and moisture. Three maritime peat bogs in the British Isles, and two high-elevation peatlands in the Czech Republic were studied. All sites were relatively wet, the mean annual temperatures were higher by up to 6 o C at the British/Irish sites than at the Czech sites. Cumulative carbon content in 210 Pb-dated Sphagnum-dominated vertical peat cores increased from the warmer to the colder sites when evaluated for the most recent decades (since ca. 1950). That would correspond to formation of thinner, more highly decomposed peat deposits over the long-term in warmer conditions, and deeper peat bogs in colder conditions. However, when cumulative carbon content was evaluated for the last ca. 150 years, no relationship was found between mean annual temperature and the carbon pool size. Even along broad present-day climatic gradients, site-specific factors controlled organic carbon preservation in peat. Pollen analysis was instrumental in corroborating the 210 Pb dates, identifying wet and dry periods in the past, and it also provided evidence for increasing nitrogen loads in wetland areas

  9. Vulnerability of the peatland carbon sink to sea-level rise

    Science.gov (United States)

    Whittle, Alex; Gallego-Sala, Angela V.

    2016-01-01

    Freshwater peatlands are carbon accumulating ecosystems where primary production exceeds organic matter decomposition rates in the soil, and therefore perform an important sink function in global carbon cycling. Typical peatland plant and microbial communities are adapted to the waterlogged, often acidic and low nutrient conditions that characterise them. Peatlands in coastal locations receive inputs of oceanic base cations that shift conditions from the environmental optimum of these communities altering the carbon balance. Blanket bogs are one such type of peatlands occurring in hyperoceanic regions. Using a blanket bog to coastal marsh transect in Northwest Scotland we assess the impacts of salt intrusion on carbon accumulation rates. A threshold concentration of salt input, caused by inundation, exists corresponding to rapid acidophilic to halophilic plant community change and a carbon accumulation decline. For the first time, we map areas of blanket bog vulnerable to sea-level rise, estimating that this equates to ~7.4% of the total extent and a 0.22 Tg yr−1 carbon sink. Globally, tropical peatlands face the proportionally greatest risk with ~61,000 km2 (~16.6% of total) lying ≤5 m elevation. In total an estimated 20.2 ± 2.5 GtC is stored in peatlands ≤5 m above sea level, which are potentially vulnerable to inundation. PMID:27354088

  10. Floristic diversity of midforest lakes (Sobibór Landscape Park, Poland

    Directory of Open Access Journals (Sweden)

    Sender Joanna

    2016-12-01

    Full Text Available Aquatic vegetation greatly impacts lake functions. Forest ecosystems surrounding lakes are effective protection zone of lakes and their associated flora and fauna. The presence of aquatic plants depends on many factors, including the chemical composition and acidity of water, the shape of the lake catchment, the angle of slope along shorelines and the management of surrounding lands. Natural ecosystems throughout Eastern Europe are threatened by anthropogenic activities. Aquatic systems and bogs are particularly sensitive to disturbances. The aim of the study was to determine the influence of land management, forest type and stand age on aquatic plant colonisation within lakes as well as to quantify and qualify the structure of macrophyte communities within two lakes, Płotycze Sobiborskie and Orchowe, located in the Sobibór Landscape Park in western Poland. Even though there were few bogs within the catchment areas and lake buffer zones, where they did occur they had the greatest effect on macrophyte presence. The results of this research indicate that in the absence of anthropogenic disturbances midforest water-bog complexes are relatively stable systems and preserve their natural character. The applied multi-criteria evaluation of macrophytes in the studied lakes and their surrounding buffer zones and catchment areas allowed the lakes to be characterised as lakes with a good ecological status.

  11. Holocene climate variability revealed by oxygen isotope analysis of Sphagnum cellulose from Walton Moss, northern England

    Science.gov (United States)

    Daley, T. J.; Barber, K. E.; Street-Perrott, F. A.; Loader, N. J.; Marshall, J. D.; Crowley, S. F.; Fisher, E. H.

    2010-07-01

    Stable isotope analyses of Sphagnum alpha-cellulose, precipitation and bog water from three sites across northwestern Europe (Raheenmore, Ireland, Walton Moss, northern England and Dosenmoor, northern Germany) over a total period of 26 months were used to investigate the nature of the climatic signal recorded by Sphagnum moss. The δ18O values of modern alpha-cellulose tracked precipitation more closely than bog water, with a mean isotopic fractionation factor αcellulose-precipitation of 1.0274 ± 0.001 (1 σ) (≈27‰). Sub-samples of isolated Sphagnum alpha-cellulose were subsequently analysed from core WLM22, Walton Moss, northern England yielding a Sphagnum-specific isotope record spanning the last 4300 years. The palaeo-record, calibrated using the modern data, provides evidence for large amplitude variations in the estimated oxygen isotope composition of precipitation during the mid- to late Holocene. Estimates of palaeotemperature change derived from statistical relationships between modern surface air temperatures and δ18O precipitation values for the British Isles give unrealistically large variation in comparison to proxies from other archives. We conclude that use of such relationships to calibrate mid-latitude palaeo-data must be undertaken with caution. The δ18O record from Sphagnum cellulose was highly correlated with a palaeoecologically-derived index of bog surface wetness (BSW), suggesting a common climatic driver.

  12. Vulnerability of the peatland carbon sink to sea-level rise

    Science.gov (United States)

    Whittle, Alex; Gallego-Sala, Angela V.

    2016-06-01

    Freshwater peatlands are carbon accumulating ecosystems where primary production exceeds organic matter decomposition rates in the soil, and therefore perform an important sink function in global carbon cycling. Typical peatland plant and microbial communities are adapted to the waterlogged, often acidic and low nutrient conditions that characterise them. Peatlands in coastal locations receive inputs of oceanic base cations that shift conditions from the environmental optimum of these communities altering the carbon balance. Blanket bogs are one such type of peatlands occurring in hyperoceanic regions. Using a blanket bog to coastal marsh transect in Northwest Scotland we assess the impacts of salt intrusion on carbon accumulation rates. A threshold concentration of salt input, caused by inundation, exists corresponding to rapid acidophilic to halophilic plant community change and a carbon accumulation decline. For the first time, we map areas of blanket bog vulnerable to sea-level rise, estimating that this equates to ~7.4% of the total extent and a 0.22 Tg yr-1 carbon sink. Globally, tropical peatlands face the proportionally greatest risk with ~61,000 km2 (~16.6% of total) lying ≤5 m elevation. In total an estimated 20.2 ± 2.5 GtC is stored in peatlands ≤5 m above sea level, which are potentially vulnerable to inundation.

  13. Hvor er nørderne, der skal sikre klimaomstillingen?

    DEFF Research Database (Denmark)

    Andersen, Frans Ørsted

    2015-01-01

    Kronikken skaber en forbindelse mellem vores nye forskningsprojekt, "Pædagogik på kanten" (som også er titlen på en ny bog, der udkom 6.11.15) og klimaproblemerne / behovet for klimaomstilling....

  14. A unique guild of Lepidoptera associated with the glacial relict populations of Labrador tea (Ledum palustre Linnaeus, 1753) in Central European peatlands (Insecta: Lepidoptera)

    Czech Academy of Sciences Publication Activity Database

    Spitzer, Karel; Jaroš, Josef

    2014-01-01

    Roč. 42, č. 166 (2014), s. 319-327 ISSN 0300-5267 Institutional support: RVO:60077344 Keywords : Insecta * Lepidoptera * relict peat bogs Subject RIV: EH - Ecology, Behaviour Impact factor: 0.435, year: 2014

  15. 低温闪蒸气压缩机气缸温度场的有限元分析%Finite Analysis of Cylinder Temperature Field in Boil-off Gas Compressor

    Institute of Scientific and Technical Information of China (English)

    杨东辉; 王雷雷; 沈宇红; 张波; 彭学院

    2013-01-01

    针对低温闪蒸气(BOG)压缩机工作时吸气温度低、变工况时气缸温度变化剧烈的问题,建立了压缩机导热有限元计算模型,得到了稳态、周期性非稳态气缸温度场及常温启动、预冷启动时气缸瞬时温度变化.研究结果表明:BOG压缩机稳定运行时气缸吸排气腔平均温度分别达-97℃和-21℃,周期性非稳态温度波动小于0.1℃.常温(30℃)启动后气缸内外壁最大温差为87.1℃,当预冷至-30℃启动时气缸内外壁最大温差仅为53.5℃,比常温启动时下降了38.6%.%Boil-off gas (BOG) compressors operate at low suction temperature and suffer from great temperature change when the working condition changes. In this study, the FEM simulation of heat transfer in a BOG compressor was performed, and the static and periodic transient temperature fields and their changes were obtained during the compressor starting both under ambient condition and precooling conditions. The results show that, when the BOG compressor operates steadily, the average temperatures in the suction chamber and the discharge chamber of the cylinder are -97 ℃ and -21 ℃, respectively, and the amplitude of temperature fluctuation is less than 0.1 ℃ in the periodic transient temperature field. In addition, the maximum temperature difference in the cylinder is 53.5 ℃ when the compressor starts at -30 ℃ while it is 87.1 ℃ when the compressor starts under the ambient condition (at 30 ℃).

  16. Oligo-Miocene peatland ecosystems of the Gippsland Basin and modern analogues

    Science.gov (United States)

    Korasidis, Vera A.; Wallace, Malcolm W.; Wagstaff, Barbara E.; Holdgate, Guy R.

    2017-02-01

    A detailed examination of the brown coal facies preserved in the Latrobe Valley Morwell 1B seam indicates that the type of peat-forming environment and the associated hydrological regime are the main factors influencing the development of lithotypes in brown coal deposits. New palynological data from the Morwell 1B seam suggests that each respective lithotype in the lightening-upwards lithotype cycles was deposited in a particular depositional environment that was characterised by a distinct floral community. The laminated dark lithotype represents a fire-prone emergent marsh that grew on the margins of a coastal lagoon and/or freshwater swamp. This facies grades into the dark lithotype, representing the transition from a meadow marsh to a periodically flooded ombrogenous forested bog. The medium and lighter lithotypes are interpreted as being deposited in an angiosperm-dominated ombrogenous forest bog that was intolerant of fire. These peat-forming environments are interpreted as being largely controlled by moisture and relative depth to water table. Each environment produces distinct lithotypes and lightening-upwards cycles are interpreted as terrestrialization cycles. As the peat grew upwards and above the water table, less moist conditions prevailed and lighter lithotypes were produced. The observed change in colour, from darker to lighter lithotypes, results from the environment evolving from anaerobic/inundated to less anaerobic/less moist settings via terrestrialization. The thin and laterally extensive light and pale lithotypes that top the cycles are interpreted to represent a residual layer of concentrated, oxidation resistant peat-forming elements that result from intense weathering and aerobic degradation of the peats. At a generic level, modern lowland bogs of South Westland in New Zealand have remarkably similar floral/ecological gradients to those of the Oligo-Miocene Morwell 1B brown coal cycles in Australia. This suggests that modern New Zealand

  17. Branched GDGT-based paleotemperature reconstruction of the last 30,000 years in humid monsoon region of Southeast China

    Science.gov (United States)

    Wang, M.

    2017-12-01

    The use of bacterial branched glycerol dialkyl glycerol tetraethers (brGDGTs) to reconstruct mean annual air temperatures (MAATs) and environmental pH from soils has sparked significant interest in the terrestrial paleoclimate community. However, the reconstruction of these climate proxies from peat bogs is rare in monsoonal regions of the East Asia. This research was carried out on a core from the Shuizhuyang (SZY) peat bog located in Fujian Province. Branched GDGT (brGDGT) indexes were used for reconstructing the paleoclimate of the last 30 cal ka. The aim was to evaluate quantitatively the MAAT and pH values since the Last Glacial Maximum (LGM) in the subtropical zone of China. Results show that the CBT-MBT'-derived MAAT at MIS 3 is about 15.6 °C on average, which is followed by a significant fall at the LGM (11.7-12.1 °C). The temperature difference between the LGM and the present-day value is as high as 5.8 °C. The synchronous variation of biomarker and pollen proxies indicates that replacement of subtropical evergreen broadleaved forests by coldtolerant, deciduous broadleaved forests was driven by the significant drop in air temperature. Our results also indicate that the Younger Dryas event lasted from about 12.9 to about 11.3 cal ka, and cooling event at 3.2 cal ka in the late Holocene was detected, showing the sensitivity of peat bogs to rapid cooling. Our pH reconstructions indicate that the pH of the bog rose during Heinrich 1 and Bølling-Allerød periods, probably due to low precipitation, and were lowest in the Holocene thermal maximum between 8 ka and 2.5 ka, probably due to higher precipitation. The decoupling of reconstructed MAAT and pH during particularly deglaciation and YD periods supports the hypothesis that the variations in temperature and precipitation are not always synchronous.

  18. Microbial communities of the deep unfrozen: Do microbes in taliks increase permafrost carbon vulnerability? (Invited)

    Science.gov (United States)

    Waldrop, M. P.; Blazewicz, S.; Jones, M.; Mcfarland, J. W.; Harden, J. W.; Euskirchen, E. S.; Turetsky, M.; Hultman, J.; Jansson, J.

    2013-12-01

    The vast frozen terrain of northern latitude ecosystems is typically thought of as being nearly biologically inert for the winter period. Yet deep within the frozen ground of northern latitude soils reside microbial communities that can remain active during the winter months. As we have shown previously, microbial communities may remain active in permafrost soils just below the freezing point of water. Though perhaps more importantly, microbial communities persist in unfrozen areas of water, soil, and sediment beneath water bodies the entire year. Microbial activity in taliks may have significant impacts on biogeochemical cycling in northern latitude ecosystems because their activity is not limited by the winter months. Here we present compositional and functional data, including long term incubation data, for microbial communities within permafrost landscapes, in permafrost and taliks, and the implications of these activities on permafrost carbon decomposition and the flux of CO2 and CH4. Our experiment was conducted at the Alaska Peatland Experiment (APEX) within the Bonanza Creek LTER in interior Alaska. Our site consists of a black spruce forest on permafrost that has degraded into thermokarst bogs at various times over the last five hundred years. We assume the parent substrate of the deep (1-1.5m) thermokarst peat was similar to the nearby forest soil and permafrost C before thaw. At this site, flux tower and autochamber data show that the thermokarst bog is a sink of CO2 , but a significant source of CH4. Yet this does not tell the whole story as these data do not fully capture microbial activity within the deep unfrozen talik layer. There is published evidence that within thermokarst bogs, relatively rapid decomposition of old forest floor material may be occurring. There are several possible mechanisms for this pattern; one possible mechanism for accelerated decomposition is the overwintering activities of microbial communities in taliks of thermokarst

  19. Global peat resources

    Energy Technology Data Exchange (ETDEWEB)

    Lappalainen, E. [ed.] [Geological Survey of Finland (Finland)

    1996-12-31

    The book provides a detailed review of the world`s peat and peatland resources and their role in the biosphere. It was compiled by 68 peat experts. Reports present the valuable mire ecosystem, its characteristics, and the use of peatlands. Maps and photographs illustrate the distribution of mines and their special characteristics, including raised bogs, aapa mires, blanket bogs, mangrove swamps, swamp forests etc. The book contains a total of 57 chapters, the bulk of then giving surveys of peat resources and use in individual countries. They are grouped under the headings: peatlands in biosphere; general review; Europe; Asia; Africa; North America; Central and South America; Australia (and New Zealand); and use of peatlands. One chapter has been abstracted separately for the IEA Coal Research CD-ROM. 7 apps.

  20. Effects of power-line construction on wetland vegetation in Massachusetts, USA

    Science.gov (United States)

    Nickerson, Norton H.; Dobberteen, Ross A.; Jarman, Nancy M.

    1989-07-01

    Utility rights-of-way corridors through wetland areas generate long-term impacts from construction activities to these valuable ecosystems. Changes to and recovery of the vegetation communities of a cattail marsh, wooded swamp, and shrub/bog wetland were documented through measurements made each growing season for two years prior, five years following, and again on the tenth year after construction of a 345-kV transmission line. While both the cattail marsh and wooded swamp recovered within a few years, measures of plant community composition in the shrub/bog wetland were still lower, compared to controls, after ten years. Long-term investigations such as the one reported here help decrease uncertainty and provide valuable information for future decision making regarding construction of power utility lines through valuable and dwindling wetland resources.

  1. Plan og virkelighed

    DEFF Research Database (Denmark)

    Kaufmann, E.

    Der er dén bagside ved altid at se fremad og lægge planer, at man ikke rigtigt får tid til at se bagud og lære af sine fejl. I denne bog er det imidlertid forsøgt at se tilbage på to mindre planer, som blev lagt for 20 år siden. Hvordan svarer virkelighed til plan?......Der er dén bagside ved altid at se fremad og lægge planer, at man ikke rigtigt får tid til at se bagud og lære af sine fejl. I denne bog er det imidlertid forsøgt at se tilbage på to mindre planer, som blev lagt for 20 år siden. Hvordan svarer virkelighed til plan?...

  2. Spiders (Araneae of stony debris in North Bohemia

    Directory of Open Access Journals (Sweden)

    Růžička, Vlastimil

    1996-12-01

    Full Text Available The arachnofauna was studied at five stony debris sites in northern Bohemia. In Central Europe, the northern and montane species inhabiting cold places live not only on mountain tops and peat bogs but also on the lower edges of boulder debris, where air streaming through the system of inner compartments gives rise to an exceedingly cold microclimate. At such cold sites, spiders can live either on bare stones (Bathyphantes simillimus, Wubanoides uralensis, or in the rich layers of moss and lichen (Diplocentria bidentata. Kratochviliella bicapitata exhibits a diplostenoecious occurence in stony debris and on the tree bark. Latithorax faustus and Theonoe minutissima display diplostenoecious occurence in stony debris and on peat bogs. The occurence of the species Scotina celans in the Czech Republic was documented for the first time.

  3. 13th PERG's annual workshop

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-07-01

    Abstracts of ten of the eleven papers presented and of the opening and closing addresses by the Industrial Research Chair in Peatland Management are included. The papers describe the influence of water table levels and substrate on cloudberry cultivation in abandoned peatlands; productivity of cloudberry in response to cultivation trials; revegetation of a peatland affected by salt water; effect of topography on water availability at the root zone in a harvested bog; fertilization and nutrients in tree plantations on cut-over peatlands; birch invasions in harvested peatlands; peat accumulation versus net carbon sink in peatland restoration; carbon dioxide exchange, water content, and ground spectral reflectance of bog vegetation communities; plant cover and restoration at Chemin- du-Lac; a survey of abandoned fens in Canada and USA; and regional plans for wetland conservation.

  4. Modeling the impacts of wetland restoration in former cranberry farms on nitrogen removal

    Science.gov (United States)

    In population-dense Massachusetts (USA) acquiring historical wetlands for ecological restoration efforts can be difficult and expensive. Retiring cranberry bogs create a rare opportunity to restore historical wetlands. Environmental managers face important decisions about how to ...

  5. Undervisningsdifferentiering og rummelighed i skolen - grænsen til specialundervisning

    DEFF Research Database (Denmark)

    Quvang, Christian

    2006-01-01

    I dette kapitel i en bog om almen didaktik peges på nødvendigheden af - og mulighederne i at tage udgangspunkt i undervisningsdifferentiering som et væsentligt bidrag til inklusion i skolens almindelige undervisning....

  6. Ecology and distribution of Myriosclerotinia caricis-ampullaceae (Sclerotiniaceae, Ascomycota) in Central Europe with remarks on its world distribution

    Czech Academy of Sciences Publication Activity Database

    Holec, J.; Kučera, Tomáš; Balner, V.

    2007-01-01

    Roč. 59, č. 1 (2007), s. 57-74 ISSN 0082-0598 Institutional research plan: CEZ:AV0Z60870520 Keywords : mycogeography * raised-bogs * mountain vegetation Subject RIV: EH - Ecology, Behaviour Impact factor: 0.556, year: 2007

  7. Paludification and forest retreat in northern oceanic environments.

    Science.gov (United States)

    Crawford, R M M; Jeffree, C E; Rees, W G

    2003-01-01

    Examination of temperature variations over the past century for Europe and the Arctic from northern Norway to Siberia suggests that variations in the North Atlantic Oscillation are associated with an increase in oceanicity in certain maritime regions. A southward depression of the tree line in favour of wet heaths, bogs and wetland tundra communities is also observed in northern oceanic environments. The physiological basis for this change in ecological succession from forest to bog is discussed in relation to the long-term effects of flooding on tree survival. The heightened values currently detected in the North Atlantic Oscillation Index, together with rising winter temperatures, and increased rainfall in many areas in northern Europe, presents an increasing risk of paludification with adverse consequences for forest regeneration, particularly in areas with oceanic climates. Climatic warming in oceanic areas may increase the area covered by bogs and, contrary to general expectations, lead to a retreat rather than an advance in the northern limit of the boreal forest. High water-table levels are not automatically detrimental to forest survival as can be seen in swamp, bottom land and mangrove forests. Consequently, the inhibitory effects of flooding on tree survival and regeneration in northern regions should not be uncritically accepted as merely due to high water levels. Evidence is discussed which suggests that physiological and ecological factors may interact to inhibit forest regeneration in habitats where there is a risk of prolonged winter-flooding combined with warmer winters and cool moist summers.

  8. Lead-210 and heavy metal contents in dated ombrotrophic peat hummocks from Finland

    International Nuclear Information System (INIS)

    El-Daoushy, F.; Tolonen, K.

    1984-01-01

    Two Sphagnum fuscum hummock cores, core 1, Kaerpaensuo bog and core F9, Kunonniemensuo bog. from Finland were used in this study. The peats are ombrotrophic and were dated using the moss-increment method. The mosses in both cores were carefully examined for their botanical composition, degree of humification, ash percentage and bulk density. The total accumulated dry peat-matter in the Kunonniemensuo core was almost double that in the Kaerpaensuo core. The total 210 Pb and the supported 210 Pb were measured by isotope dilution and the radon emanation technique. Materials in the same peat samples were analysed for their 210 Pb content at the Institute of Physics, Uppsala, Sweden and the Technical Research Centre of Finland, Espoo, Finland. The annual content of unsupported 210 Pb in the dated peat-layers shows that peat materials are effective traps which could yield information on atmospheric-fluxes both chronologically and regionally. Lead, copper, zinc, iron and manganese were also measured by flame atomic absorption spectrometry (AAS). The total accumulated amounts over the past 150 y of the heavy metals investigated are almost identical for both cores apart from manganese which is considerably higher in the Kunonniemensuo core. However, the metal profiles studied exhibit discontinuity zones more pronounced in the Kunonniemensuo core. The 210 Pb data indicate that growth rate and bulk density variations in ombrotrophic peat bogs affects the accumulation of 210 Pb and similar trace metals. (orig.)

  9. Nutrient stoichiometry in Sphagnum along a nitrogen deposition gradient in highly polluted region of Central-East Europe

    Energy Technology Data Exchange (ETDEWEB)

    Jirousek, Martin, E-mail: machozrut@mail.muni.c [Department of Botany and Zoology, Faculty of Science, Masaryk University, Kotlarska 2, 61137 Brno (Czech Republic); Hajek, Michal [Department of Botany and Zoology, Faculty of Science, Masaryk University, Kotlarska 2, 61137 Brno (Czech Republic); Bragazza, Luca [WSL Swiss Federal Institute for Forest, Snow and Landscape Research, Site Lausanne, Station 2, Case Postale 96, CH-1015 Lausanne (Switzerland); Ecole Polytechnique Federale de Lausanne (EPFL), Laboratory of Ecological Systems - ECOS, Batiment GR, Station 2, CH-1015 Lausanne (Switzerland); Department of Biology and Evolution, University of Ferrara, Corso Ercole I d' Este 32, I-44100 Ferrara (Italy)

    2011-02-15

    We investigated the variation of N:P and N:K ratio in ombrotrophic Sphagnum plants along a gradient of atmospheric N deposition from 1 to 2.5 g m{sup -2} year{sup -1} in Central-East Europe. The N:P and N:K ratio in Sphagnum capitula increased significantly along the N deposition gradient. Sphagnum species from the Cuspidata section were characterised by significantly lower ratios at low N deposition. When we compared the observed N:P ratios in Sphagnum plants with the values reported in a previous European-wide study, we found a correspondence in nutrient stoichiometry only for a few bogs: higher P concentration in Sphagnum capitula caused a lower N:P ratio in most of the study bogs so that Sphagnum plants still seem N-limited despite their N saturation. Interaction between summer water table decrease and aerial liming of surrounding forests is proposed as an explanation for this discrepancy. Local forestry practice interacting with climate thus alter N:P stoichiometry of Sphagnum along the N deposition gradient. - Research highlights: Despite high atmopsheric nitrogen deposition, Sphagnum mosses still have rather low N:P ratio. Regional climate and landscape management can enhance P and K availability in bogs. Sphagnum species of the Cuspidata section were characterised by lower N:P ratio. - Regional climate and local forestry practices are expected to alter nutrient stoichiometry in Sphagnum mosses at high atmospheric N deposition in Central-East Europe.

  10. Nutrient stoichiometry in Sphagnum along a nitrogen deposition gradient in highly polluted region of Central-East Europe

    International Nuclear Information System (INIS)

    Jirousek, Martin; Hajek, Michal; Bragazza, Luca

    2011-01-01

    We investigated the variation of N:P and N:K ratio in ombrotrophic Sphagnum plants along a gradient of atmospheric N deposition from 1 to 2.5 g m -2 year -1 in Central-East Europe. The N:P and N:K ratio in Sphagnum capitula increased significantly along the N deposition gradient. Sphagnum species from the Cuspidata section were characterised by significantly lower ratios at low N deposition. When we compared the observed N:P ratios in Sphagnum plants with the values reported in a previous European-wide study, we found a correspondence in nutrient stoichiometry only for a few bogs: higher P concentration in Sphagnum capitula caused a lower N:P ratio in most of the study bogs so that Sphagnum plants still seem N-limited despite their N saturation. Interaction between summer water table decrease and aerial liming of surrounding forests is proposed as an explanation for this discrepancy. Local forestry practice interacting with climate thus alter N:P stoichiometry of Sphagnum along the N deposition gradient. - Research highlights: → Despite high atmopsheric nitrogen deposition, Sphagnum mosses still have rather low N:P ratio.→ Regional climate and landscape management can enhance P and K availability in bogs. → Sphagnum species of the Cuspidata section were characterised by lower N:P ratio. - Regional climate and local forestry practices are expected to alter nutrient stoichiometry in Sphagnum mosses at high atmospheric N deposition in Central-East Europe.

  11. Cirque Glacier on South Georgia Shows Centennial Variability over the Last 7000 Years

    Directory of Open Access Journals (Sweden)

    Lea T. Oppedal

    2018-02-01

    Full Text Available A 7000 year-long cirque glacier reconstruction from South Georgia, based on detailed analysis of fine-grained sediments deposited downstream in a bog and a lake, suggests continued presence during most of the Holocene. Glacier activity is inferred from various sedimentary properties including magnetic susceptibility (MS, dry bulk density (DBD, loss-on-ignition (LOI and geochemical elements (XRF, and tallied to a set of terminal moraines. The two independently dated sediment records document concurring events of enhanced glacigenic sediment influx to the bog and lake, whereas the upstream moraines afford the opportunity to calculate past Equilibrium Line Altitudes (ELA which has varied in the order of 70 m altitude. Combined, the records provide new evidence of cirque glacier fluctuations on South Georgia. Based on the onset of peat formation, the study site was deglaciated prior to 9900 ± 250 years ago when Neumayer tidewater glacier retreated up-fjord. Changes in the lake and bog sediment properties indicate that the cirque glacier was close to its maximum Holocene extent between 7200 ± 400 and 4800 ± 200 cal BP, 2700 ± 150 and 2000 ± 200 cal BP, 500 ± 150–300 ± 100 cal BP, and in the Twentieth century (likely 1930s. The glacier fluctuations are largely in-phase with reconstructed Patagonian glaciers, implying that they respond to centennial climate variability possibly connected to corresponding modulations of the Southern Westerly Winds.

  12. A Mycoplasma species of Emydidae turtles in the northeastern USA.

    Science.gov (United States)

    Ossiboff, Robert J; Raphael, Bonnie L; Ammazzalorso, Alyssa D; Seimon, Tracie A; Niederriter, Holly; Zarate, Brian; Newton, Alisa L; McAloose, Denise

    2015-04-01

    Mycoplasma infections can cause significant morbidity and mortality in captive and wild chelonians. As part of a health assessment of endangered bog turtles (Glyptemys muhlenbergii) in the northeastern US, choanal and cloacal swabs from these and other sympatric species, including spotted turtles (Clemmys guttata), eastern box turtles (Terrapene carolina carolina), wood turtles (Glyptemys insculpta), and common snapping turtles (Chelydra serpentina) from 10 sampling sites in the states (US) of Delaware, New Jersey, and Pennsylvania, were tested by PCR for Mycoplasma. Of 108 turtles tested, 63 (58.3%) were PCR positive for Mycoplasma including 58 of 83 bog turtles (70%), three of three (100%) eastern box turtles, and two of 11 (18%) spotted turtles; all snapping turtles (n = 7) and wood turtles (n = 4) were negative. Sequence analysis of portions of the 16S-23S intergenic spacer region and the 16S ribosomal RNA gene revealed a single, unclassified species of Mycoplasma that has been previously reported in eastern box turtles, ornate box turtles (Terrapene ornata ornata), western pond turtles (Emys marmorata), and red-eared sliders (Trachemys scripta elegans). We document a high incidence of Mycoplasma, in the absence of clinical disease, in wild emydid turtles. These findings, along with wide distribution of the identified Mycoplasma sp. across a broad geographic region, suggest this bacterium is likely a commensal inhabitant of bog turtles, and possibly other species of emydid turtles, in the northeastern US.

  13. Vyrmethane. Progress report stage 5. In situ production of methane gas from peat

    Energy Technology Data Exchange (ETDEWEB)

    Martinell, R

    1982-12-01

    The Vyrmethane process means that bog water containing methane gas is circulated in a closed system and degassed. By this procedure the microbiological activity in the bog stimulates and new methane is produced and dissolved in the water, which circulates to a degassing station. From the degassing station the methane gas can be used for different purposes and the degassed water is infiltrated back in the peat bog. The degradation process is described by McCarty (Stanford 1964). According to this description all COD (Chemical Oxygen Demand) is supposed to be converted to methane. The Vyrmethane method does not reach this ideal result. Consequently the produced gas also includes carbon dioxide. The running cost for the process is mainly depending on the water circulation e.g. the demand of energy for the pumps. Consequently the result is propotional to the methane, which can be degassed from the circulated water. The results reached, so far, indicate that one added unit of mechanical energy is giving five units of heat energy in the form of methane gas. Better results are in prospect. This report, which is a following up of the pilot plants started up after 1978, is discussing the technical and economical conditions for the process. Consequently it is suggested that a number of full-scale prototype plants are built, studied further and that preparations are made for a demonstration stage including about 200 plants with geographical spreading out.

  14. Cirque glacier on South Georgia shows centennial variability over the last 7000 years

    Science.gov (United States)

    Oppedal, Lea T.; Bakke, Jostein; Paasche, Øyvind; Werner, Johannes P.; van der Bilt, Willem G. M.

    2018-02-01

    A 7000 year-long cirque glacier reconstruction from South Georgia, based on detailed analysis of fine-grained sediments deposited downstream in a bog and a lake, suggests continued presence during most of the Holocene. Glacier activity is inferred from various sedimentary properties including magnetic susceptibility (MS), dry bulk density (DBD), loss-on-ignition (LOI) and geochemical elements (XRF), and tallied to a set of terminal moraines. The two independently dated sediment records document concurring events of enhanced glacigenic sediment influx to the bog and lake, whereas the upstream moraines afford the opportunity to calculate past Equilibrium Line Altitudes (ELA) which has varied in the order of 70 m altitude. Combined, the records provide new evidence of cirque glacier fluctuations on South Georgia. Based on the onset of peat formation, the study site was deglaciated prior to 9900±250 years ago when Neumayer tidewater glacier retreated up-fjord. Changes in the lake and bog sediment properties indicate that the cirque glacier was close to its maximum Holocene extent between 7200±400 and 4800±200 cal BP, 2700±150 and 2000±200 cal BP, 500±150-300±100 cal BP, and in the 20th century (likely 1930s). The glacier fluctuations are largely in-phase with reconstructed Patagonian glaciers, implying that they respond to centennial climate variability possibly connected to corresponding modulations of the Southern Westerly Winds.

  15. Vegetation change and the protection of the Csaroda relic mires, Hungary

    Directory of Open Access Journals (Sweden)

    Tibor Simon

    2014-01-01

    Full Text Available Study of vegetation change of the protected mires situated near Csaroda and Beregdaróc (the Great Hungarian Plain are presented. These are the southermost mires with raised bog communities in the plains of Europe. In the past few decades (by the early 80-s vegetation showed both qualitative and quantitative signs of degradation. These changes were caused by natural (climatic variation, succesion and by human effects. Natural changes were following: the decline or extinction of hygrophytes, the expansion of hydromesophytes and mesophytes and the acceleration of forest growth. The most important human-caused change was the drainage of the bogs. The harmful processes had slight effect on the Sphagnum-dominated associations. The "original" (i.e. before drying out state of mires has been recovered by blocking drainage canals, plantation of a buffor zone and prohibition of using chemicals.

  16. Energy budgets of animals: behavioral and ecological implications

    Energy Technology Data Exchange (ETDEWEB)

    Porter, W P

    1979-01-01

    This year's progress has been: (1) to extend the general microclimate model two ways: (a) to incorporate wet ground surfaces (bogs), and (b) to incorporate slope effects. Tests of the model in a Michigan bog and the Galapagos Islands show temperature accuracies to within 4/sup 0/C at worst at any soil or air location, which is about a 2% error in estimation of metabolism. (2) The addition to ectotherm modeling an analysis of: (a) reproduction in heterogeneous and uncertain environments; (b) prediction of distribution limits due to egg incubation requirements; (c) addition of appendage-torso modeling and tests on large ectotherms; (d) social systems interactions with environmental and physiological variables; and (3) to continue the endotherm (deer mouse) experimental research and extend the growth and reproduction studies to include the entire reproductive and growth cycle in the deer mouse.

  17. The multiplicity of the digital textbook as design object

    DEFF Research Database (Denmark)

    Riis Ebbesen, Toke

    2015-01-01

    Building on a preliminary case study of the Danish educational publisher Systime A/S and its flagship product, the web-based ‘iBog’/‘iBook’, this article explores how digital textbooks can be understood as design. The shaping of digital books is seen as being intertwined in a wider circuit...... reorganization of the publishing company, web-based user interfaces, and ultimately the branding, which market these new digital objects, are building power- ful discourses around the product. Thus it is suggested that the design process of the iBog case can be understood in a model of database-based publishing...... with multiple levels. In the final analysis, the iBog is much more than a product and a technology. It is a brand that goes beyond what can be studied by looking at the digital textbook as a singular artefact....

  18. Design in the digital textbook

    DEFF Research Database (Denmark)

    Ebbesen, Toke Riis

    reorganization of the publishing company, web based user interfaces, and ultimately the branding, that market these new digital objects, are building powerful discourses around the product. Thus it is suggested that the design process of the iBog-case can be understood in a model of database-based publishing......Building on a preliminary case study of the Danish educational publisher, Systime A/S, and its flagship product, the web based ‘iBog’ {Systime 2014}, this paper explores how digital textbooks can be understood as design. The shaping of digital books is seen as intertwined in a wider circuit...... with multiple levels. In the final analysis, the iBog is much more than a product and a technology. It is a brand that goes beyond what can be studied by looking at the digital textbook as a singular artefact....

  19. Can seasonal variation in fen water chemistry influence the reliability of vegetation-environment analyses?

    Czech Academy of Sciences Publication Activity Database

    Hájek, Michal; Hekera, P.

    2004-01-01

    Roč. 76, - (2004), s. 1-14 ISSN 0032-7786 R&D Projects: GA AV ČR KSK6005114 Institutional research plan: CEZ:AV0Z6005908 Keywords : anion and cation concentration * bog * central Europe Subject RIV: EF - Botanics

  20. Forskning og undervisning i skriftsprog

    DEFF Research Database (Denmark)

    Perregaard, Bettina

    Bettina Perregaard giver i denne bog en introduktion til L.S. Vygotskys kulturhistoriske teori og afdækker den videnskabshistoriske baggrund for forskning i forholdet mellem social interaktion og skriftsproglig udvikling. Bogen diskuterer begreber som internalisering, udviklingszone, social praksis...

  1. Morphogenetic Litter Types of Bog Spruce Forests

    Directory of Open Access Journals (Sweden)

    T. T. Efremova

    2015-02-01

    Full Text Available For the first time the representation of moss litter morphogenetic structure of valley-riverside and streamside spruce forests was determined for the wetland intermountain area of Kuznetsk Alatau. In general, the litter of (green moss-hypnum spruce forest can be characterized as medium thickness (9–17 cm with high storage of organic matter (77–99 t/ha, which differs in neutral environmental conditions pH 6.8–7.0 and high percentage of ash 11–28 %. Formation litter types were identified, which depend on the content of mineral inclusions in organogenic substrate and the degree of its drainage. The differentiation of litter subhorizons was performed, visual diagnostic indicators of fermentative layers were characterized, and additional (indexes to indicate their specificity were developed. Peat- and peaty-fermentative, humified-fermentative and (black mold humus-fermentative layers were selected. Peat- and peaty-fermentative layers are characterized by content of platy peat macroaggregates of coarse vegetable composition, the presence of abundant fungal mycelium and soil animals are the primary decomposers – myriopoda, gastropoda mollusks. Humified-fermentative layers are identified by including the newly formed amorphous humus-like substances, nutty-granular structural parts of humus nature and soil animals’ humificators – enchytraeids and earthworms. (Black mold humus-fermentative layers are diagnosed by indicators with similar humified-fermentative, but differ from them in clay-humus composition of nutty-granular blue-grey parts. The nomenclature and classification of moss litter were developed on the basis of their diagnostic characteristics of fermentative layers – peat, peaty, reduced peaty, (black mold humus-peaty, reduced (black mold humus-peaty. Using the method of discriminant analysis, we revealed that the physical-chemical properties, mainly percentage of ash and decomposition degree of plant substrate, objectively characterizes the uniqueness of moss litter types, their horizons and fermentation layers. These results confirm the feasibility of using morphogenetic structure of litter for the purposes of classification, reflecting the rate of substances turnover, parcel structure and production potential of forest peat soils. The obtained materials are important for the prediction of the transformation of Kuznetsk Alatau forest wetland depressions in connection with global and local climate fluctuations.

  2. On the ecology of a Sphagnum Bog

    NARCIS (Netherlands)

    Baas Becking, L.G.M.; Nicolai, E.

    1934-01-01

    For the ecologist systematic units are actors in a play. Whatever their christian- and family-names may be — it is their role, whether master or servant, whether villain or hero — which determines the character of the performance. This performance has, moreover, the property of being both continuous

  3. Variation in photosynthetic properties among bog plants

    Czech Academy of Sciences Publication Activity Database

    Korrensalo, A.; Hájek, Tomáš; Vesala, T.; Mehtätalo, L.; Tuittila, E. S.

    2016-01-01

    Roč. 94, č. 12 (2016), s. 1127-1139 ISSN 1916-2790 Institutional support: RVO:67985939 Keywords : CO2 * photosynthesis rate * plant functional types Subject RIV: EH - Ecology, Behaviour Impact factor: 1.224, year: 2016

  4. Modelling evaporation from a drained and rewetted peatland

    NARCIS (Netherlands)

    Spieksma, J F M; Moors, EJ; Dolman, A J; Schouwenaars, J M

    1997-01-01

    Evaporation from a cutover raised bog in The Netherlands was modelled using a detailed, physically based evaporation model for heterogeneous vegetation and unsaturated soil water how ''SWAPS''. The model enables a quantification of the role of heterogeneity on evaporation. Micro-meteorological

  5. Kampen om erhvervslivet

    DEFF Research Database (Denmark)

    Johannsen, Carl Gustav

    2010-01-01

    På grundlag af Carl Gustav Johannsens bog "Firmabiblioteker i Danmark 1945-2007" beskriver artiklen, hvordan danske firmabibliotekers historie peger på et lavt konfliktniveau i forhold til forskningsbibliotekerne. Til gengæld rivaliserede forskningsbibliotekerne med folkebibliotekerne i slut-80'e...

  6. Forvist til omsorg

    DEFF Research Database (Denmark)

    Jensen, Niels Rosendal

    2008-01-01

    Anmeldelsen refererer til en netop udgivet bog af Grønbæk Jensen & Knigge og udbygger dennes problemstilling ved at tilføje en diskussion om forholdet mellem faglighed og nærhed/hjemstavn. Udgivelsesdato: December 2008...

  7. Financial Management In Public Secondary Schools In Kenya A Case Study Of Lurambi Sub-County Kakamega County

    Directory of Open Access Journals (Sweden)

    Rose Kahavizakiriza

    2015-08-01

    Full Text Available Abstract This study set out to identify knowledge skills and attitudes required by principals of public secondary schools in Lurambi Sub-county in Kakamega County Kenya for effective financial management. The rationale for focusing on the financial management of public secondary schools was based on evidence in contemporary literature showing that there existed problems in schools over the management of funds because parents complained of financial mismanagement. The main objective of this study was to find outfinancial management in public secondary schools in Kenya. The specific objectives were To find out whether principals of public secondary schools identify and mobilize financial resources for their institutions to find out whether principals draw up budgets for their schools according to priorities of the school needs to find out whether supervision monitoring and control of the budget is carried out by principals of public secondary schools. Therefore there was need to find out ways of ensuring efficient financial management in schools. The study was carried out in public secondary schools in Lurambi Sub-county of Kakamega County covering Lurambi and Municipality. The target population for this study consisted of seventeen 17 principals of public secondary schools seventeen 17 school bursars one hundred and thirty six 136 H.O.Ds and seventeen 17 B.O.G representatives giving a total of one hundred and eighty seven 187 people. Sample population was purposively selected from twelve 12 public secondary schools in Lurambi Sub-county through simple random within the clusters of principals school bursars H.O.Ds representatives of B.O.G. The study adopted a descriptive survey design which helped to establish and describe the knowledge skills and attitudes principals of public secondary schools require for effective performance. Reliability coefficient of the instruments was calculated using cronbachs reliability test. Data analysis revealed that

  8. 75 FR 67408 - Excepted Service

    Science.gov (United States)

    2010-11-02

    ... Global Food Security. Effective September 2, 2010. DAGS00242 Chief of Staff for Marketing and Regulatory... BOGS10023 Confidential Assistant for Strategic Planning and Communications. Effective September 8, 2010. Office of National Drug Control Policy QQGS10012 Associate Director for Public Affairs. Effective...

  9. Bacteriohopanepolyol signatures as markers for methanotrophic bacteria in peat moss

    NARCIS (Netherlands)

    van Winden, J.F.; Talbot, H.M.; Kip, N.; Reichart, G.J.; Pol, A.; McNamara, N.P.; Jetten, M.S.M.; Op den Camp, H.J.M.; Sinninghe Damsté, J.S.

    2012-01-01

    Bacteriohopanepolyols (BHPs) are bacterial biomarkers with a likely potential to identify present and past methanotrophic communities. To unravel the methanotrophic community in peat bogs, we report the BHP signatures of type I and type II methanotrophs isolated from Sphagnum mosses and of an

  10. Bacteriohopanepolyol signatures as markers for methanotrophic bacteria in peat moss

    NARCIS (Netherlands)

    Winden, J.F. van; Talbot, H.M.; Kip, N.; Reichart, G.-J.; Pol, A.; McNamara, N.P.; Jetten, M.S.M.; Camp, H.J.M. Op den; Sinninghe Damsté, J.S.

    2012-01-01

    Bacteriohopanepolyols (BHPs) are bacterial biomarkers with a likely potential to identify present and past methanotrophic communities. To unravel the methanotrophic community inpeat bogs, we report the BHP signatures of type I and type II methanotrophs isolated from Sphagnummosses and of an extreme

  11. A comparative study of long-term Hg and Pb sediment archives.

    Czech Academy of Sciences Publication Activity Database

    Norton, S. A.; Jacobson, G. L.; Kopáček, Jiří; Navrátil, Tomáš

    2016-01-01

    Roč. 13, č. 3 (2016), s. 517-527 ISSN 1448-2517 Institutional support: RVO:60077344 ; RVO:67985831 Keywords : bog sediment * lake sediment * lead * mercury * pollution archives Subject RIV: DJ - Water Pollution ; Quality; DD - Geochemistry (GLU-S) Impact factor: 3.516, year: 2016

  12. Unsaturated hydraulic properties of xerophilous mosses: towards implementation of moss covered soils in hydrological models

    NARCIS (Netherlands)

    Voortman, B.R.; Bartholomeus, R.P.; Bodegom, van P.M.; Gooren, H.P.A.; Zee, van der S.E.A.T.M.; Witte, J.P.M.

    2014-01-01

    Evaporation from mosses and lichens can form a major component of the water balance, especially in ecosystems where mosses and lichens often grow abundantly, such as tundra, deserts and bogs. To facilitate moss representation in hydrological models, we parameterized the unsaturated hydraulic

  13. How Does Tree Density Affect Water Loss of Peatlands? A Mesocosm Experiment

    NARCIS (Netherlands)

    Limpens, J.; Holmgren, M.; Jacobs, C.M.J.; Zee, van der S.E.A.T.M.; Karofeld, E.; Berendse, F.

    2014-01-01

    Raised bogs have accumulated more atmospheric carbon than any other terrestrial ecosystem on Earth. Climate-induced expansion of trees and shrubs may turn these ecosystems from net carbon sinks into sources when associated with reduced water tables. Increasing water loss through tree

  14. 75 FR 35834 - Receipt of Applications for Endangered Species Permits

    Science.gov (United States)

    2010-06-23

    ... authorization to monitor the effects of management activities in Apalachicola National Forest in Liberty and... fire moss spider (Microhexura montivaga), and bog turtle (Clemmys muhlenbergii) in North Carolina to... species of freshwater mussels, amphibians, reptiles, birds, and bats throughout Alabama, Arkansas, Florida...

  15. 75 FR 17683 - Cooperative Conservation Partnership Initiative-Chesapeake Bay Watershed

    Science.gov (United States)

    2010-04-07

    ... governments, Federally recognized Indian Tribes, producer associations, farmer cooperatives, institutions of... has requested to participate in EQIP or WHIP. Beginning Farmer or Rancher means a person or legal..., orchards, vineyards, cropped woodland, marshes, cranberry bogs, and other lands used for crop production...

  16. Plant macrofossils analysis from Steregoiu NW Romania: taphonomy, representation, and comparison with pollen analysis

    Directory of Open Access Journals (Sweden)

    Angelica Feurdean

    2008-08-01

    Full Text Available This paper presents the results of macrofossil analysis from the Steregoiu sequence in the Gutaiului Mountains covering the last 8,000 cal BP. The studied peat deposit is characterized by abundant macrofossils. Their diversity is, however, low with most macrofossils coming from plants that grew on the mire and in the forest surrounding the basin (Carex spp., Cyperus sp., Urtica dioica, Potentilla erecta, Filipendula ulmaria, Rubus idaeus, Lycopus europaeus. The concentration of Picea abies macrofossils correlates partially well with its pollen percentages, and only when it has been present on the bog surface. The absence of macrofossils from deciduous trees, which were abundant in the surrounding vegetation according to the pollen data, suggests that these deciduous trees were not growing on the bog or around its margins. The combined macrofossil and the pollen results assists in the understanding of the differences between the local and regional flora.

  17. Preservation status and priorities for in situ monitoring of the weapon sacrifice in Illerup Ådal, Denmark

    DEFF Research Database (Denmark)

    Tjellden, Anna Katarina Ejgreen; Kristiansen, Søren Munch; Botfeldt, Knud B.

    2012-01-01

    Excavations of the southern part of a very rich sacrificial bog in Illerup Ådal, Denmark between 1950 and 1985 recovered approximately 15,000 Iron Age artefacts. At the time, 60% of the area was left unexcavated and thousands of objects are now preserved in situ, but the present preservation status...... has not been investigated for approximately 25 years. Extensive in situ monitoring was carried out for one year in order to present a prioritized plan for further monitoring of the unexcavated areas, producing documentation of groundwater table variations, water quality and vegetation in the area....... Results show that the remaining artefacts in general are well preserved in the waterlogged and anaerobic environment. However, in the north-eastern part of the bog, the groundwater table is too low even in a year when net precipitation and hydrological conditions were near normal. Here, slow, continuous...

  18. Preservation status and priorities for in situ monitoring of the weapon sacrifice in Illerup Ådal, Denmark

    DEFF Research Database (Denmark)

    Tjelldén, A.K.E.; Kristiansen, S.M.; Botfeldt, Knud Bo

    2012-01-01

    Excavations of the southern part of a very rich sacrificial bog in Illerup Ådal, Denmark between 1950 and 1985 recovered approximately 15,000 Iron Age artefacts. At the time, 60 per cent of the area was left unexcavated and thousands of objects are now preserved in situ, but the present preservation...... status has not been investigated for approximately twenty-five years. Extensive in situ monitoring was carried out for one year in order to present a prioritized plan for further monitoring of the unexcavated areas, producing documentation of groundwater table variations, water quality and vegetation...... in the area. Results show that the remaining artefacts are generally well preserved in a waterlogged and anaerobic environment. However, in the north-eastern part of the bog, the groundwater table is too low even in a year when net precipitation and hydrological conditions were near normal. In the centre...

  19. Somatisk embryogense og kryopræservering af eg og bøg

    DEFF Research Database (Denmark)

    MMH Kristensen, Michel; Find, Jens; Krogstrup, Peter

    Somatisk embryogenese og kryopræservering af eg og bøg Traditionel vegetativ formering af eg og bøg er vanskeligt, dyrt og har ingen større praktisk anvendelse i skovbruget. Opbevaring af agern og bog i frøbanker erligeledesproblematiskidetspiringsevnenfalderdramatiskalleredeiløbetafdetoførsteåre......Somatisk embryogenese og kryopræservering af eg og bøg Traditionel vegetativ formering af eg og bøg er vanskeligt, dyrt og har ingen større praktisk anvendelse i skovbruget. Opbevaring af agern og bog i frøbanker...... holdbarheden er flere hundrede år. Arbejdet med eg og bøg er en del af et større projekt, Videreudvikling af bioteknologiske metoder, med henblik på forædling og opbevaring af plantegenetiske ressourcer for skovtræer i Danmark 2003- 2006. Det overordnede formål med projektet var at udvikle metoder til...

  20. The importance of water quality to wetland establishment

    Energy Technology Data Exchange (ETDEWEB)

    Trites, M.; Bayley, S. [Alberta Univ., Edmonton, AB (Canada). Dept. of Biological Sciences

    2010-07-01

    Extracting oil from sands produces huge volumes of saline tailings. This presentation demonstrated that the ability to recreate boreal peatland communities after oil sands mining will be constrained by water quality. Typical boreal wetlands can be described along a bog to poor fen to rich fen gradient that correlates to increasing water pH and calcium concentration. There are major differences in vegetation communities along this gradient. Bogs and poor fens are characterized by slowly decomposing Sphagnum moss, while brown moss and productive herbaceous communities characterize rich fens. Post-mining wetlands generally have sodium concentrations above the tolerance limits of most freshwater peatland species. This study involved a survey of 25 boreal wetlands across a natural salinity gradient to determine a suite of potential native vegetation species to use for oils sand reclamation. Sixteen herbaceous vegetation communities that could be incorporated into oil sands wetlands were identified, but the diversity of communities decreased as salinity increased. Some of these wetlands had thick organic matter accumulations, despite having salinity equal to or higher than oil sands wetlands. Organic matter accumulation rates were also measured. If salinity is moderate and nutrient levels adequate, highly productive species like Carex aquatilis and Typha latifolia can accumulate organic matter quickly. Triglochin maritima can accumulate organic matter over the long term, even if salinity is high and nutrient levels are low. Although there is potential for peat to accumulate in future oil sands wetlands, the rates of peat accumulation will probably be slower than in undisturbed freshwater bogs and fens because of the elevated salinity. tabs., figs.

  1. The importance of water quality to wetland establishment

    International Nuclear Information System (INIS)

    Trites, M.; Bayley, S.

    2010-01-01

    Extracting oil from sands produces huge volumes of saline tailings. This presentation demonstrated that the ability to recreate boreal peatland communities after oil sands mining will be constrained by water quality. Typical boreal wetlands can be described along a bog to poor fen to rich fen gradient that correlates to increasing water pH and calcium concentration. There are major differences in vegetation communities along this gradient. Bogs and poor fens are characterized by slowly decomposing Sphagnum moss, while brown moss and productive herbaceous communities characterize rich fens. Post-mining wetlands generally have sodium concentrations above the tolerance limits of most freshwater peatland species. This study involved a survey of 25 boreal wetlands across a natural salinity gradient to determine a suite of potential native vegetation species to use for oils sand reclamation. Sixteen herbaceous vegetation communities that could be incorporated into oil sands wetlands were identified, but the diversity of communities decreased as salinity increased. Some of these wetlands had thick organic matter accumulations, despite having salinity equal to or higher than oil sands wetlands. Organic matter accumulation rates were also measured. If salinity is moderate and nutrient levels adequate, highly productive species like Carex aquatilis and Typha latifolia can accumulate organic matter quickly. Triglochin maritima can accumulate organic matter over the long term, even if salinity is high and nutrient levels are low. Although there is potential for peat to accumulate in future oil sands wetlands, the rates of peat accumulation will probably be slower than in undisturbed freshwater bogs and fens because of the elevated salinity. tabs., figs.

  2. Convergent development of anodic bacterial communities in microbial fuel cells.

    KAUST Repository

    Yates, Matthew D

    2012-05-10

    Microbial fuel cells (MFCs) are often inoculated from a single wastewater source. The extent that the inoculum affects community development or power production is unknown. The stable anodic microbial communities in MFCs were examined using three inocula: a wastewater treatment plant sample known to produce consistent power densities, a second wastewater treatment plant sample, and an anaerobic bog sediment. The bog-inoculated MFCs initially produced higher power densities than the wastewater-inoculated MFCs, but after 20 cycles all MFCs on average converged to similar voltages (470±20 mV) and maximum power densities (590±170 mW m(-2)). The power output from replicate bog-inoculated MFCs was not significantly different, but one wastewater-inoculated MFC (UAJA3 (UAJA, University Area Joint Authority Wastewater Treatment Plant)) produced substantially less power. Denaturing gradient gel electrophoresis profiling showed a stable exoelectrogenic biofilm community in all samples after 11 cycles. After 16 cycles the predominance of Geobacter spp. in anode communities was identified using 16S rRNA gene clone libraries (58±10%), fluorescent in-situ hybridization (FISH) (63±6%) and pyrosequencing (81±4%). While the clone library analysis for the underperforming UAJA3 had a significantly lower percentage of Geobacter spp. sequences (36%), suggesting that a predominance of this microbe was needed for convergent power densities, the lower percentage of this species was not verified by FISH or pyrosequencing analyses. These results show that the predominance of Geobacter spp. in acetate-fed systems was consistent with good MFC performance and independent of the inoculum source.

  3. Tarkkaturve - Peat production on shallow fields; Tarkkaturve - mataloituvien soiden tuotantomenetelmien ja laitteiden kehittaeminen

    Energy Technology Data Exchange (ETDEWEB)

    Nurminen, T; Honkanen, J; Jormalainen, R; Laaksoharju, T; Rytkoenen, P; Viitanen, J [Vapo Oy, Jyvaeskylae (Finland); Aho, V J; Aalto, J; Kallio, M; Leinonen, A.; Tiihonen, I [VTT Energy, Jyvaeskylae (Finland)

    1997-12-01

    It is important to produce the peat of the bogs under production as completely as possible when improving the efficiency and economy of milled peat production. Hence the service life of bog areas is being extended, and the investment costs per produced peat mass are decreased. Research, in which new planning, production and ditching methods, as well as production machines for production from shallowing fields, has been carried out in order to obtain the targets. Data obtained from charting of the bog, by which it is possible to take the regional differences of the production areas into account while planning and making of the production strips and ditching, is used in planning of the production fields. Stones are removed from the strips on the mineral soil areas during preparation of the fields, and peat is conveyed from the depletable areas into production strips, hence it is possible to make ditching with open ditches excavated into mineral soil. The new milled peat production machines are lighter than the older ones, and non-sparkling materials, e.g. plastics, are used in the construction of them in every phase of the production. The new machines are able to operate on strips of varying width and on the fields of poor load carrying capacity. Brushing technology is used in collection of peat. By this method it is possible to improve in addition to the fire safety, also the collecting accuracy, and hence the efficiency of the production. The new methods and equipment developed in the researches are now in wide utilisation in Finnish peat production. (orig.)

  4. Experimental warming differentially affects microbial structure and activity in two contrasted moisture sites in a Sphagnum-dominated peatland.

    Science.gov (United States)

    Delarue, Frédéric; Buttler, Alexandre; Bragazza, Luca; Grasset, Laurent; Jassey, Vincent E J; Gogo, Sébastien; Laggoun-Défarge, Fatima

    2015-04-01

    Several studies on the impact of climate warming have indicated that peat decomposition/mineralization will be enhanced. Most of these studies deal with the impact of experimental warming during summer when prevalent abiotic conditions are favorable to decomposition. Here, we investigated the effect of experimental air warming by open-top chambers (OTCs) on water-extractable organic matter (WEOM), microbial biomasses and enzymatic activities in two contrasted moisture sites named Bog and Fen sites, the latter considered as the wetter ones. While no or few changes in peat temperature and water content appeared under the overall effect of OTCs, we observed that air warming smoothed water content differences and led to a decrease in mean peat temperature at the warmed Bog sites. This thermal discrepancy between the two sites led to contrasting changes in microbial structure and activities: a rise in hydrolytic activity at the warmed Bog sites and a relative enhancement of bacterial biomass at the warmed Fen sites. These features were not associated with any change in WEOM properties namely carbon and sugar contents and aromaticity, suggesting that air warming did not trigger any shift in OM decomposition. Using various tools, we show that the use of single indicators of OM decomposition can lead to fallacious conclusions. Lastly, these patterns may change seasonally as a consequence of complex interactions between groundwater level and air warming, suggesting the need to improve our knowledge using a high time-resolution approach. Copyright © 2015 Elsevier B.V. All rights reserved.

  5. Chemical and optical changes in freshwater dissolved organic matter exposed to solar radiation

    Science.gov (United States)

    Osburn, C.L.; Morris, D.P.; Thorn, K.A.; Moeller, R.E.

    2001-01-01

    We studied the chemical and optical changes in the dissolved organic matter (DOM) from two freshwater lakes and a Sphagnum bog after exposure to solar radiation. Stable carbon isotopes and solid-state 13C-NMR spectra of DOM were used together with optical and chemical data to interpret results from experimental exposures of DOM to sunlight and from seasonal observations of two lakes in northeastern Pennsylvania. Solar photochemical oxidation of humic-rich bog DOM to smaller LMW compounds and to DIC was inferred from losses of UV absorbance, optical indices of molecular weight and changes in DOM chemistry. Experimentally, we observed a 1.2??? enrichment in ??13C and a 47% loss in aromatic C functionality in bog DOM samples exposed to solar UVR. Similar results were observed in the surface waters of both lakes. In late summer hypolimnetic water in humic Lake Lacawac, we observed 3 to 4.5??? enrichments in ??13C and a 30% increase in aromatic C relative to early spring values during spring mixing. These changes coincided with increases in molecular weight and UV absorbance. Anaerobic conditions of the hypolimnion in Lake Lacawac suggest that microbial metabolism may be turning over allochthonous C introduced during spring mixing, as well as autochthonous C. This metabolic activity produces HMW DOM during the summer, which is photochemically labile and isotopically distinct from allochthonous DOM or autochthonous DOM. These results suggest both photooxidation of allochthonous DOM in the epilimnion and autotrophic production of DOM by bacteria in the hypolimnion cause seasonal trends in the UV absorbance of lakes.

  6. The Importance of Microtopography and Nurse Canopy for Successful Restoration Planting of the Slow-Growing Conifer Pilgerodendron uviferum

    Directory of Open Access Journals (Sweden)

    Jürgen Bauhus

    2013-01-01

    Full Text Available Recent studies have shown that, owing to a lack of seed trees, the natural rate of recovery of fire-disturbed bog forests previously dominated by the endemic and endangered conifer Pilgerodendron uviferum (D. Don Florin is extremely slow. Hence, increasing the number of seed trees in the landscape through restoration planting could remove the principal biotic filter, limiting recovery of these forests. Here, we analyzed how the success of restoration plantings may be improved through the choice or manipulation of microsites in P. uviferum forests on Chiloé Island in North Patagonia. For this purpose, we manipulated microtopography in water-logged sites in bogs (mounds, flat terrain, mineral soil and changed canopy conditions (gaps, semi-open, closed canopy in upland sites with better drainage. In bogs, there was no significant effect of microtopography on growth and survival of P. uviferum plantings. However, fluorescence measurements indicated lower stress in seedlings established on mounds. Seedlings in upland areas established beneath a nurse canopy had lower mortality and higher relative shoot growth, foliar nutrients, photosynthetic light use efficiency and chlorophyll fluorescence values than those planted in the open. This indicates that seedlings of the slow growing P. uviferum can tolerate extremely wet conditions, yet suffer from stress when grown in the open. Here, the removal of canopy appeared to have also removed or reduced mycorrhizal networks for seedlings, leading to poorer nutrition and growth. Based on these results, recommendations for restoration plantings in highly degraded P. uviferum forests are presented.

  7. TARKKATURVE - Peat production on shallow fields; TARKKATURVE - mataloituvien soiden tuotantomenetelmien ja laitteiden kehittaeminen

    Energy Technology Data Exchange (ETDEWEB)

    Nurminen, T. [Vapo Oy, Jyvaeskylae (Finland); Aho, V.J.; Tiihonen, I. [VTT Energy, Jyvaeskylae (Finland)

    1996-12-31

    It is important to produce the peat of the bogs under production as completely as possible when improving the efficiency and economy of milled peat production. Hence the service life of bog areas is being extended, and the investment costs per produced peat mass are decreased. Research, in which new planning, production and ditching methods, as well as production machines for production from shallowing fields, has been carried out in order to obtain the targets. Data obtained from charting of the bog, by which it is possible to take the regional differences of the production areas into account while planning and making of the production strips and ditching, is used in planning of the production fields. Stones are removed from the strips on the mineral soil areas during preparation of the fields, and peat is conveyed from the depleted areas into production strips, hence it is possible to make ditching with open ditches excavated into mineral soil. The new milled peat production machines are lighter than the older ones, and non-sparkling materials, e.g. plastics, are used in the construction of them in every phase of the production. The new machines are able to operate on strips of varying width and on the fields of poor load carrying capacity. Brushing technology is used in collection of peat. By this method it is possible to improve in addition to the fire safety, also the collecting accuracy, and hence the efficiency of the production. The new methods and equipment developed in the researches are now in wide utilization in Finnish peat production

  8. 75 FR 47031 - Excepted Service

    Science.gov (United States)

    2010-08-04

    ... Marketing. Effective June 11, 2010. GSGS01443 Congressional Relations Specialist for Congressional and... Confidential Assistant to the General Counsel. Effective June 4, 2010. BOGS10022 Advisor to the Director, Office of Management and Budget. Effective June 30, 2010. Department of State DSGS70110 Special Assistant...

  9. Weyerhaeuser Export Facility at DuPont. Volume I.

    Science.gov (United States)

    1982-05-01

    exists on the DuPont site, in which the most common trees are lodgepole pine ( Pinus contorta) and western hemlock (Tsuga heterophtlla). Bog birch (Betula...Weyerhaeuser production facilities and storage at the proposed export facility. Tropolone methyl ethers have also been mentioned as potential contam

  10. Monitoring revitalizačních zásahů na rašeliništi Žofinka, CHKO Třeboňsko

    Czech Academy of Sciences Publication Activity Database

    Rektoris, Ladislav; Kolmanová, Andrea; Jakšičová, T.

    -, - (2003), s. 117-132 ISSN 1211-3603 R&D Projects: GA MŽP SE/610/10/00; GA ČR GA206/98/0727 Institutional research plan: CEZ:AV0Z6005908 Keywords : postfire succession * pine bog forests * soil water chemistry Subject RIV: EF - Botanics

  11. Alpine wetlands in the West Carpathians: vegetation survey and vegetation - environment relationships

    Czech Academy of Sciences Publication Activity Database

    Sekulová, L.; Hájek, Michal; Hájková, Petra; Mikulášková, E.; Rozbrojová, Zuzana

    2011-01-01

    Roč. 83, č. 1 (2011), s. 1-24 ISSN 0032-7786 R&D Projects: GA ČR GAP505/10/0638 Institutional research plan: CEZ:AV0Z60050516 Keywords : bogs * environmantal gradiens * fens Subject RIV: EF - Botanics Impact factor: 2.521, year: 2011

  12. Testing OSL failures against a regional glaciation chronology from southern Scandinavia

    DEFF Research Database (Denmark)

    Houmark-Nielsen, Michael

    2008-01-01

    Middle Weichselian periglacial strata and Last Glacial Maximum (LGM) ice proximal deposits showing pre-LGM ages. Suggestions are given as to how the depositional environment may influence the dating results. Even though independent dating anchors the marine Cyprina clay and last interglacial peat bogs...

  13. Videnskabsteori i Samfundsvidenskaberne

    DEFF Research Database (Denmark)

    2013-01-01

    Inden for samfundsvidenskaberne findes der mange forskellige og ofte modstridende antagelser om, hvordan viden opbygges, hvad samfundet er, og hvad der indgår i samfundsvidenskabelig analyse. Denne bog sigter på at give en samlende og loyal fremstilling af de mest fremherskende videnskabsteoretiske...

  14. Mineral nutrient economy in competing species of Sphagnum mosses

    Czech Academy of Sciences Publication Activity Database

    Hájek, Tomáš; Adamec, Lubomír

    2009-01-01

    Roč. 24, č. 2 (2009), s. 291-302 ISSN 0912-3814 R&D Projects: GA AV ČR KJB600050503 Institutional research plan: CEZ:AV0Z60050516 Keywords : exchange capacity * species coexistence * bog Subject RIV: EF - Botanics Impact factor: 1.485, year: 2009

  15. The Extended Mind Thesis and Mechanistic Explanations

    DEFF Research Database (Denmark)

    Fazekas, Peter

    2013-01-01

    The Extended Mind Thesis (EMT) is traditionally formulated against the bedrock of functionalism, and ongoing debates are typically bogged down with questions concerning the exact relationship between EMT and different versions of functionalism. In this paper, I offer a novel ally for EMT: the new...

  16. 76 FR 15888 - Special Regulations; Areas of the National Park System, Cape Cod National Seashore

    Science.gov (United States)

    2011-03-22

    ... flora and fauna, the physiographic conditions and the historic sites and structures be permanently... wild cranberry bogs provide a glimpse into Cape Cod's past and continuing life ways. The Seashore... Military Reservation, have their own special regulations that have different dates than the standard dates...

  17. Biobeschikbaarheid in de hond van anorganisch arseen uit ijzeroerhoudende grond

    NARCIS (Netherlands)

    Groen K; Vaessen HAMG; Kliest JJG; de Boer JLM; van Ooik A; Timmerman A; Vlug R

    1992-01-01

    In some parts of the Netherlands, bog-ore containing soils prevail which naturally contain arsenic concentrations that exceed, by a factor of ten, existing standards for maximum allowable concentrations of inorganic arsenic in soil. These standards are based on the assumption that in humans the

  18. Det er systemet den er gal med

    DEFF Research Database (Denmark)

    Bryld, Claus

    2014-01-01

    Anmeldelse af Klaus Buster Jensen og Jakob Mathiassen: Kamppladser. Østarbejdere og social dumping i byggeriet. Informations forlag. En fremragende bog om social dumping evner at udfolde det store problem uden at gøre hverken østeuropæerne eller arbejdsgiverne til karikerede skurke...

  19. Normalitet og afvigelse

    DEFF Research Database (Denmark)

    Holst, Jesper

    2009-01-01

    Anmeldelse ad Ivar Morkens bog:" Normalitet og afvigelse", der tager udgangspunkt i kontrasten mellem visionerne om inklusion, empowerment og anerkendelse og de faktiske forhold, hvor menneskelig afvig stadig diagnosticeres. Kontrasterne defineres og forsøges imødegået med forskellige former for ...

  20. Holocene history and environmental reconstruction of a Hercynian mire and surrounding mountain landscape based on multiple proxies

    Czech Academy of Sciences Publication Activity Database

    Dudová, Lydie; Hájková, Petra; Opravilová, V.; Hájek, Michal

    2014-01-01

    Roč. 82, č. 1 (2014), s. 107-120 ISSN 0033-5894 R&D Projects: GA ČR GA206/08/0389 Institutional support: RVO:67985939 Keywords : fen-bog transition * transfer functions * macrofossil and pollen analysis Subject RIV: EF - Botanics Impact factor: 2.544, year: 2014