WorldWideScience

Sample records for bogs

  1. Jobs Bog

    DEFF Research Database (Denmark)

    Nielsen, Kirsten

    2015-01-01

    Indledningen sætter Jobs Bog ind i den bibelske kontekst og redegør for hovedindhold og genre.......Indledningen sætter Jobs Bog ind i den bibelske kontekst og redegør for hovedindhold og genre....

  2. Ruths Bog

    DEFF Research Database (Denmark)

    Nielsen, Kirsten

    2015-01-01

    Indledningen sætter Ruths Bog ind i den bibelske kontekst og redegør for hovedindhold og genre.......Indledningen sætter Ruths Bog ind i den bibelske kontekst og redegør for hovedindhold og genre....

  3. Bog bodies

    DEFF Research Database (Denmark)

    Lynnerup, Niels

    2015-01-01

    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...... and shrink, leading to potential pitfalls in paleopathological diagnostics. Bog bodies have in several instances been crucial in determining the last meal, as gut contents may be preserved, and thus augment our knowledge on pre-historic diet by adding to, for example, stable isotope analyses. This article...

  4. Project Bog Turtle

    OpenAIRE

    North Carolina Herpetological Society

    2007-01-01

    Project Bog Turtle South was started by the Conservation Committee of the North Carolina Herpetological Society in 1995 to protect the bog turtle and its habitat throughout the southeastern US. This is being done through leases, purchases or easements on bog turtle habitats, habitat restoration, scientific research, and education. The project is currently providing bog turtle protection for six sites in the Georgia and North Carolina areas.

  5. Lowland Bogs, Fens and Reedswamps

    OpenAIRE

    Bracken, Fintan; Smiddy, Patrick

    2012-01-01

    This chapter reviews the current and historical studies of the bird communities of lowland bogs, fens and reedswamps in Ireland. The habitat types and bird communities described include raised bogs, cutover and cutaway peatlands and reedswamps.

  6. Analysis of the hydrology of raised bogs in the Irish Midlands : A case study of Raheenmore Bog and Clara Bog

    NARCIS (Netherlands)

    Schaaf, van der S.

    1999-01-01

    In the framework of the Irish-Dutch Raised Bog Project the hydrology of two raised bogs in the Irish Midlands, Raheenmore Bog and Clara Bog, was studied.The work focuses on relationships in the bog system and how they are affected by drain-age and turf cutting along margins. The concept of diplotelm

  7. 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...

  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. Skeletal analysis and comparison of bog bodies from Northern European peat bogs

    Science.gov (United States)

    Pestka, Jan M.; Barvencik, Florian; Beil, Frank T.; Marshall, Robert P.; Jopp, Eilin; Schilling, Arndt F.; Bauerochse, Andreas; Fansa, Mamoun; Püschel, Klaus; Amling, Michael

    2010-04-01

    Although numerous bodies were deposited in Western European bogs in the past centuries, few were found and underwent archeological analysis. No studies comparing skeletal structure and mineralization of bog bodies from different ages have been performed to this day. Therefore, the aim of this study was to analyze and compare skeletal features and specifics of the human remains of three bog bodies from the Iron and Middle Ages found in Northern European peat bogs. Demineralization due to the acidic environment in peat bogs was comparably pronounced in all three bodies. Still, the macroscopic state of skeletal preservation was excellent. In addition to contact radiography, we used peripheral quantitative computed tomography to measure cortical bone mineral density. The conservation of skeletal three-dimensional microstructural elements was assessed by high-resolution microcomputed tomography analysis. These techniques revealed severe differences in bone mineral density and enabled us to determine handedness in all three bodies. Additionally, unique skeletal features like intravital bone lesions, immobilization osteoporosis, and Harris lines were found. A deformity of the left femoral head was observed which had the typical appearance of an advanced stage of Legg-Calve-Perthes disease. This study gives detailed insight into the skeletal microstructure and microarchitecture of 800- to 2,700-year-old bog bodies. Skeletal analysis enables us to draw conclusions not only concerning changes in the acidic environment of the bog, but also serves as a diagnostic tool to unravel life circumstances and diseases suffered by humans in the Iron and Middle Ages.

  10. Medical Imaging of Mummies and Bog Bodies

    DEFF Research Database (Denmark)

    Lynnerup, Niels

    2010-01-01

    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...

  11. Distribution of bog and heath in a Newfoundland blanket bog complex: topographic limits on the hydrological processes governing blanket bog development

    Directory of Open Access Journals (Sweden)

    P. A. Graniero

    1999-01-01

    Full Text Available This research quantified the role of topography and hydrological processes within and, hence, the development of, blanket bogs. Topographic characteristics were derived from digital elevation models (DEMs developed for the surface and underlying substrate at three blanket bog sites on the southeastern lobe of the Avalon Peninsula, Newfoundland. A multinomial logit (MNL model of the probability of bog occurrence was constructed in terms of relevant topographic characteristics. The resulting model was then used to investigate the probabilistic boundary conditions of bog occurrence within the landscape. Under average curvatures for the sites studied, substrate slopes up to 0.065 favoured blanket bog development. However, steeper slopes could, theoretically, be occupied by blanked bog where water is concentrated by convergent curvatures or large contributing areas. Near community boundaries, bog and heath communities both occupied similar topographic conditions. Since these boundary locations are capable of supporting the hydrological conditions necessary for bog development, the heath is likely to be encroached upon by bog.

  12. Acidophilic Methanotrophic Communities from Sphagnum Peat Bogs

    OpenAIRE

    Dedysh, Svetlana N.; Nicolai S. Panikov; Tiedje, James M.

    1998-01-01

    Highly enriched methanotrophic communities (>25 serial transfers) were obtained from acidic ombrotrophic peat bogs from four boreal forest sites. The enrichment strategy involved using media conditions that were associated with the highest rates of methane uptake by the original peat samples, namely, the use of diluted mineral medium of low buffering capacity, moderate incubation temperature (20°C), and pH values of 3 to 6. Enriched communities contained a mixture of rod-shaped bacteria arran...

  13. The peat bogs of Tierra del Fuego, Argentina

    Energy Technology Data Exchange (ETDEWEB)

    Rabassa, J.; Coronato, A. [Centro Austral de Investigaciones Cientificas, Ushuaia (Argentina); Roig, C. [Universidad Nacional de la Patagonia, Ushuaia (Argentina). Catedra de Geograffa Fisica

    1996-12-31

    The peat bogs and peat deposits of Argentina are briefly described, with emphasis on the island of Tierra del Fuego, where the vast majority of the bogs are concentrated, due to environmental and climatic conditions. The Fuegian bogs are a source of peaty materials, presently used in soil-improving techniques. Further studies are needed to establish other technological possibilities. From the scientific point of view, the Fuegian bogs are outstanding palaeoclimatic and palaeoenvironmental data banks, due to their uninterrupted continuity since Late Glacial times and their exceptional pollen record and subfossil wood remains. (orig.) (9 refs.)

  14. Bog discharge from different viewpoints: comparison of Ingram's theory with observations from an Estonian raised bog

    Science.gov (United States)

    Oosterwoud, Marieke; van der Ploeg, Martine; van der Zee, Sjoerd

    2013-04-01

    Raised bogs are typically dome shaped and have a groundwater level located close to the soil surface. Besides their typical dome shape, these peatlands are often characterized by a pronounced surface topography consisting of pools, wet depressions (hollows), stretches of Sphagnum species (lawns), drier mounds (hummocks) and higher drier areas with terrestrial vegetation (ridges). These peat bodies drain laterally by gravity to adjacent areas with lower groundwater levels. The integrity of these bogs is only ascertained when water is stored in the peat body in periods of precipitation deficit and efficiently removed in wet periods. This is realized by the fact that the bog's top layer, often called acrotelm, has a variable hydraulic conductivity. In response to precipitation its hydraulic conductivity increases, whereas, under evaporative demand the water table lowers and therefore also the hydraulic conductivity decreases. Ingram proposed a model based on the Dupuit-Forchheimer approximation for Darcy's law that assumes vertical flow is negligible, and the slope of the water table is equal to the hydraulic gradient. U- Hm2- K = L2 (1) where U is net recharge (P-ET), K is horizontal hydraulic conductivity, Hm is hydraulic head above a flat bottom at the centre of the bog, L is half the width of the bog along the cross section. This model incorporates the assumption that all net rainfall reaching the water table will be discharged to the stream. Ingram's model does not consider local heterogeneities in surface topography, like pool-ridge patterns. We hypothesize that under drier conditions it is likely that pool-ridge patterning will inhibit water from flowing along the surface gradient. Under wet conditions, however, pools can become connected and water can move through the upper highly permeable layer of ridges. In this study, we investigated the influence of ridge-pool patterning on the horizontal water flow through a raised bog and compared it with Ingram

  15. 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.

  16. 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.

  17. Can a bog drained for forestry be a stronger carbon sink than a natural bog forest?

    Science.gov (United States)

    Hommeltenberg, J.; Schmid, H. P.; Drösler, M.; Werle, P.

    2014-07-01

    This study compares the CO2 exchange of a natural bog forest, and of a bog drained for forestry in the pre-Alpine region of southern Germany. The sites are separated by only 10 km, they share the same soil formation history and are exposed to the same climate and weather conditions. In contrast, they differ in land use history: at the Schechenfilz site a natural bog-pine forest (Pinus mugo ssp. rotundata) grows on an undisturbed, about 5 m thick peat layer; at Mooseurach a planted spruce forest (Picea abies) grows on drained and degraded peat (3.4 m). The net ecosystem exchange of CO2 (NEE) at both sites has been investigated for 2 years (July 2010-June 2012), using the eddy covariance technique. Our results indicate that the drained, forested bog at Mooseurach is a much stronger carbon dioxide sink (-130 ± 31 and -300 ± 66 g C m-2 a-1 in the first and second year, respectively) than the natural bog forest at Schechenfilz (-53 ± 28 and -73 ± 38 g C m-2 a-1). The strong net CO2 uptake can be explained by the high gross primary productivity of the 44-year old spruces that over-compensates the two-times stronger ecosystem respiration at the drained site. The larger productivity of the spruces can be clearly attributed to the larger plant area index (PAI) of the spruce site. However, even though current flux measurements indicate strong CO2 uptake of the drained spruce forest, the site is a strong net CO2 source when the whole life-cycle since forest planting is considered. It is important to access this result in terms of the long-term biome balance. To do so, we used historical data to estimate the difference between carbon fixation by the spruces and the carbon loss from the peat due to drainage since forest planting. This rough estimate indicates a strong carbon release of +134 t C ha-1 within the last 44 years. Thus, the spruces would need to grow for another 100 years at about the current rate, to compensate the potential peat loss of the former years. In

  18. 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.

  19. Lichens as indicators of bog-community degeneration

    Directory of Open Access Journals (Sweden)

    Wiesław Fałtynowicz

    2014-08-01

    Full Text Available The lichen flora of raised and transition-bogs in West Pomerania (N Poland is poor and characterized by dominance of acidophilous epiphytes associated with pine bark, and of humus-loving lichens. Lichens are not good indicators of the degradation of transition and raised-bog phytocoenoses, mainly because it is difficult to properly determine their response - whether it is caused by natural or anthropogenic factors. U does not seem possible to create a lichenoindicative system for bogs, similar to that used in studies of the pollution of the atmospheric air. Lichens can successfully be used in analyses of changes in thc vegetation of isolated bogs; this should, however, be done at the most in addition to other procedures used to determine the degree of naturalness of plant communities.

  20. Natural Communities of Yellow Bogs in Lewis, Bloomfield and Brunswick Vermont

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Yellow Bogs in Essex County, Vermont is a unique ecological area characterized by boreal, lowland forests and extensive bog systems. Within the area, black spruce...

  1. 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....

  2. Restoration of a Terrestrialized Soak Lake of an Irish Raised Bog: Results of Field Experiments

    NARCIS (Netherlands)

    Crushell, P.H.; Smolders, A.J.P.; Schouten, M.G.C.; Robroek, B.J.M.; Wirdum, van G.; Roelofs, J.G.M.

    2011-01-01

    Soaks (areas of mesotrophic/minerotrophic vegetation within acid bog) add to the overall heterogeneity and biodiversity of raised bog landscapes due to the presence of flora and fauna communities not typically associated with acid bog systems. A field experiment was set up to investigate the potenti

  3. Ecology of the peat-bogs of Quebec-Labrador; Ecologie des tourbieres du Quebec-Labrador

    Energy Technology Data Exchange (ETDEWEB)

    Payette, S.; Rochefort, L. (comps.)

    2001-07-01

    The 24 chapters are arranged into five parts. The structure of peat bogs covers physical and geographical environment, types of peat bogs, mosses, vegetation gradients, hydrology, diversity and distribution of birds, and arthropods. Functioning of peat bogs describes biochemical processes, gases emitted, drainage, climate change, glaciation; and organic sols. Fossil analysis, morphology, entomology, pollen, diatoms, and ligneous fossils are discussed in the section on methods for bog reconstitution. In the evolution of peat bogs in the Holocene, stratigraphy and paleohydrology are described. The utilization of peat bogs contains chapters on history of the landscape transformed by harvesting, economics and value of peat, agricultural use of bogs, forestry, restoration, and conservation. 2000 refs.

  4. 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.

  5. Aged anthropogenic iodine in a boreal peat bog

    Energy Technology Data Exchange (ETDEWEB)

    Maillant, S. [Laboratoire Sols et Environnement, UMR 1120 INPL-INRA, 54500 Vandoeuvre-les-Nancy (France); Andra, Direction Scientifique, Service Transferts, 1-7 rue Jean Monnet, 92298 Chatenay-Malabry Cedex (France); Sheppard, M.I. [ECOMatters, P.O. Box 430, Pinawa, Manitoba (Canada); Echevarria, G. [Laboratoire Sols et Environnement, UMR 1120 INPL-INRA, 54500 Vandoeuvre-les-Nancy (France)]. E-mail: Guillaume.Echevarria@ensaia.inpl-nancy.fr; Denys, S. [Laboratoire Sols et Environnement, UMR 1120 INPL-INRA, 54500 Vandoeuvre-les-Nancy (France); Andra, Direction Scientifique, Service Transferts, 1-7 rue Jean Monnet, 92298 Chatenay-Malabry Cedex (France); Villemin, G. [Laboratoire Sols et Environnement, UMR 1120 INPL-INRA, 54500 Vandoeuvre-les-Nancy (France); Tekely, P. [Laboratoire de Methodologie RMN, FRE CNRS 2415, Universite Henri Poincare, Nancy 1, Faculte des Sciences, 54506 Vandoeuvre-les-Nancy (France); Leclerc-Cessac, E. [Andra, Direction Scientifique, Service Transferts, 1-7 rue Jean Monnet, 92298 Chatenay-Malabry Cedex (France); Morel, J.L. [Laboratoire Sols et Environnement, UMR 1120 INPL-INRA, 54500 Vandoeuvre-les-Nancy (France)

    2007-05-15

    This in situ study assesses the long term sorption of I in a natural peat bog, a matter that is scarcely addressed but required for safety studies such as for radioactive waste disposal. Fifteen years after the artificial contamination of a boreal peat bog, the groundwater (piezometers), the peat and the vegetation were resampled to determine I distribution with comparison to the initial situation (1989). Spectroscopic analyses (SS-NMR, electronic microscopy and EDX spectroscopy) were carried out on the peat solids to identify the sorption processes. Over the past 15 a the I has been spreading mostly outwards and possibly upwards in the groundwater. Sorption of I is higher at the surface of the bog (K {sub d} = 37.6 L kg{sup -1}) than at the bottom (K {sub d} = 5.1 L kg{sup -1}), and this is attributed to the oxic/anoxic conditions of the peat layers. The average surface K {sub d} values showed more than a 2-fold increase after 15 a. TEM-EDX analyses of the surface peat showed here for the first time that I was only associated with natural polyphenolic substances contained in humified plant tissues. Plants growing in the bog have not taken up much I with the exception of sedge species ([I]{sub sedgeleaves} is up to 283 mg kg{sup -1})

  6. Aged anthropogenic iodine in a boreal peat bog

    International Nuclear Information System (INIS)

    This in situ study assesses the long term sorption of I in a natural peat bog, a matter that is scarcely addressed but required for safety studies such as for radioactive waste disposal. Fifteen years after the artificial contamination of a boreal peat bog, the groundwater (piezometers), the peat and the vegetation were resampled to determine I distribution with comparison to the initial situation (1989). Spectroscopic analyses (SS-NMR, electronic microscopy and EDX spectroscopy) were carried out on the peat solids to identify the sorption processes. Over the past 15 a the I has been spreading mostly outwards and possibly upwards in the groundwater. Sorption of I is higher at the surface of the bog (K d = 37.6 L kg-1) than at the bottom (K d = 5.1 L kg-1), and this is attributed to the oxic/anoxic conditions of the peat layers. The average surface K d values showed more than a 2-fold increase after 15 a. TEM-EDX analyses of the surface peat showed here for the first time that I was only associated with natural polyphenolic substances contained in humified plant tissues. Plants growing in the bog have not taken up much I with the exception of sedge species ([I]sedgeleaves is up to 283 mg kg-1)

  7. 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, ther

  8. Dating recent peat accumulation in European ombrotrophic bogs

    NARCIS (Netherlands)

    J. van der Plicht; D. Yeloff; M. van der Linden; B. van Geel; S. Brain; F.M. Chambers; J. Webb; P. Toms

    2013-01-01

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

  9. 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

  10. 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 expla

  11. Oribatid mite species numbers increase, densities decline and parthenogenetic species suffer during bog degradation.

    Science.gov (United States)

    Seniczak, Anna; Seniczak, Stanisław; Maraun, Mark; Graczyk, Radomir; Mistrzak, Marcin

    2016-04-01

    This study compared the oribatid mites in two natural and four industrially exploited bogs. One natural bog (Zakręt, Z) was located in northeastern Poland and the other one (Toporowy Staw Niżni, TSN), in southern Poland. The four exploited bogs were also located in southern Poland and can be ranked from least to most degraded as follows: Łysa Puścizna (LP), Baligówka (B), Puścizna Mała (PM) and Kaczmarka (K). In the natural bogs, the water pH was higher than in the degraded ones, but other parameters were lower (conductivity, colour value, oxygen demand, and concentration of chlorides). In the natural bogs, the Oribatida were highly abundant (average density was 169,100 ind./m(2)), but with low species diversity and one dominating species. In bog Z the most abundant was Limnozetes foveolatus that had dominance of 75 % and in bog TSN, located at higher altitude, Trimalaconothrus maior dominated (73 %). In two degraded bogs that had still good water conditions (LP and B) the oribatid communities resembled those from the natural bogs; in LP the most abundant species was Hydrozetes lacustris and in bog B, L. foveolatus. In contrast, in two more degraded bogs (PM and K) the abundance of mites was lower (average density was 17,850 ind./m(2)), species diversity of the Oribatida was higher, and no species achieved a high dominance like in the natural bogs. Additionally, in more degraded bogs the abundance of parthenogenetic species was lower than in the natural bogs.

  12. Species identification of archaeological skin objects from Danish bogs

    DEFF Research Database (Denmark)

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

    2014-01-01

    species used for the production of skin garments. Until recently, species identification of archaeological skin was primarily performed by light and scanning electron microscopy or the analysis of ancient DNA. However, the efficacy of these methods can be limited due to the harsh, mostly acidic...... 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...

  13. Bog bilberry phenolics, antioxidant capacity and nutrient profile.

    Science.gov (United States)

    Colak, Nesrin; Torun, Hülya; Gruz, Jiri; Strnad, Miroslav; Hermosín-Gutiérrez, Isidro; Hayirlioglu-Ayaz, Sema; Ayaz, Faik Ahmet

    2016-06-15

    Phenolics and nutrient profiles of bog bilberry (Vaccinium uliginosum L.) collected from high mountain pastures in northeast Anatolia (Turkey) were examined for the first time in this study. The major soluble sugar identified in the berry was fructose, following by glucose, and the main organic acid identified was citric acid, followed by malic acid. Eleven phenolic acids and 17 anthocyanin 3-glycosides were identified and quantified. Caffeic acid in the free and glycoside forms and syringic acid in the ester form were the major phenolic acids, and the major individual anthocyanin present in the berry was malvidin 3-glucoside (24%). The highest total phenolics and anthocyanin contents were obtained from the anthocyanin fraction in conjunction with the highest antioxidant capacity, followed by the polyphenolic and aqueous fractions, FRAP, ORAC and DPPH, in that order. Our findings can be used to compare bog bilberry with other Vaccinium berries and to help clarify the relative potential health benefits of different berries.

  14. 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.

  15. Metabolism of nonparticulate phosphorus in an acid bog lake

    International Nuclear Information System (INIS)

    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

  16. Chemical records of environmental pollution in ombrotrophic peat bogs

    OpenAIRE

    Cloy, Joanna Marie

    2006-01-01

    Human activity has affected metal emissions to the atmosphere on a global scale for several thousand years, resulting in widespread contamination of the environment with toxic heavy metals such as Pb and Hg, thereby threatening both human and environmental health. In recent years ombrotrophic peat bogs have been used to study the changing rates and sources of atmospheric metal deposition, as they receive all their water and nutrients from the atmosphere by dry and wet deposition alone. Cores ...

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

    Science.gov (United States)

    Török, B.; Thiele, A.

    2013-12-01

    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.

  18. Effects of elevated CO2 and increased N deposition on bog vegetation in the Netherlands

    OpenAIRE

    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 plants. The aim of this study was to investigate the effects of elevated atmospheric carbon dioxide (CO 2 ) and increased nitrogen (N) deposition on bog vegetation in the Netherlands, with special attention to the relationship betw...

  19. Environmental controls of greenhouse gas release in a restoring peat bog in NW Germany

    OpenAIRE

    S. Glatzel; I. Forbrich; Krüger, C.; Lemke, S.; Gerold, G.

    2008-01-01

    In Central Europe, most bogs have a history of drainage and many of them are currently being restored. Success of restoration as well as greenhouse gas exchange of these bogs is influenced by environmental stress factors as drought and atmospheric nitrogen deposition. We determined the methane and nitrous oxide exchange of sites in the strongly decomposed center and less decomposed edge of the Pietzmoor bog in NW Germany in 2004. Also, we examined the methane and nitrous oxide exchange of mes...

  20. Dating Danish textiles and skins from bog finds by means of 14C AMS

    DEFF Research Database (Denmark)

    Mannering, Ulla; Possnert, Göran; Heinemeier, Jan;

    2010-01-01

    This paper presents the results of 44 new 14C analyses of Danish Early Iron Age textiles and skins. Of 52 Danish bog finds containing skin and textile items, 30 are associated with bog bodies. Until now, only 18 of these have been dated. In this paper we add dates to the remaining finds....... The results demonstrate that the Danish custom of depositing clothed bodies in a bog is centred to the centuries immediately before and at the beginning of the Common Era. Most of these bodies are carefully placed in the bog - wrapped or dressed in various textile and/or skin garments....

  1. Key plant species and succession patterns associated to past fen-bog transitions - perspective to future

    Science.gov (United States)

    Väliranta, Minna; Luoto, Miska; Juutinen, Sari; Korhola, Atte; Tuittila, Eeva-stiina

    2016-04-01

    Minerotrophic fens and ombrotrophic bogs differ in their hydrology, vegetation and carbon dynamics and their geographical distribution seems to be linked to certain climate parameters, such as temperature and effective precipitation. Currently bogs dominate the southern boreal zone but the climate warming with altered temperature and effective precipitation may shift the distribution of bog zone northwards. In this study, we first used plant macrofossil method and radiocarbon analysis to identify and date past fen-bog transitions. These transitions were compared to major Holocene climate phases. Subsequently, palaeoecological data were associated to ecological and environmental data collected along the current fen-bog ecotone in Finland. We identified three successional phases 1) initial minerotrophic fen phase 2) Eriophorum vaginatum-dominated oligotrophic fen phase which was followed by 3) ombrorophic bog phase. Duration of these phases varied but late Holocene timing of fen-bog transition showed some consistency. Based on palaeoecological data 57 % of the modern ecotone peatlands were classified to be in a fen phase, 10 % were in an Eriophorum-dominated phase and 33 % were going through a transition from fen to bog. The study showed that regime shifts are driven by autogenic succession and climate but also fires may efficiently control succession pathways. Our results support the hypothesis that climate change can promote the ombrotrophication process in the southern border of the fen-bog ecotone due to changes in hydrology balance.

  2. 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...... been visualized from CT-scans using the Mimics software from Materialise. Extensive manual editing was necessary, as is common with bog bodies, since the bones were severely degraded and the ordinary range of Hounsfield Units (HU), used for clinical work, is not suitable. Only the cranium, the left...

  3. 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

  4. Terrestrial isopod community as indicator of succession in a peat bog

    Directory of Open Access Journals (Sweden)

    Ivan Antonović

    2012-03-01

    Full Text Available Terrestrial isopods were studied in the Dubravica peat bog and surrounding forest in the northwestern Croatia. Sampling was conducted using pitfall traps over a two year period. Studied peat bog has a history of drastically decrease in area during the last five decades mainly due to the process of natural succession and changes in the water level. A total of 389 isopod individuals belonging to 8 species were captured. Species richness did not significantly differ between bog, edge and surrounding forest. High species richness at the bog is most likely the result of progressive vegetation succession, small size of the bog and interspecific relationships, such as predation. With spreading of Molinia grass on the peat bog, upper layers of Sphagnum mosses become less humid and probably more suitable for forest species that slowly colonise bog area. The highest diversity was found at the edge mainly due to the edge effect and seasonal immigration, but also possibly due to high abundance and predator pressure of the Myrmica ants and lycosid spiders at the bog site. The most abundant species were Trachelipus rathkii and Protracheoniscus politus, in the bog area and in the forest, respectively. Bog specific species were not recorded and the majority of the species collected belong to the group of tyrphoneutral species. However, Hyloniscus adonis could be considered as a tyrphoxenous species regarding its habitat preferences. Most of collected isopod species are widespread eurytopic species that usually inhabit various habitats and therefore indicate negative successive changes or degradation processes in the peat bog.

  5. 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

  6. 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 increasi

  7. 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 increasi

  8. 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

  9. Dissolved organic nitrogen dominates in European bogs under increasing atmospheric N deposition

    NARCIS (Netherlands)

    Bragazza, L.; Limpens, J.

    2004-01-01

    To assess the effects of increased atmospheric N input on N availability in ombrotrophic peatlands, the relative concentrations of dissolved organic nitrogen (DON) to dissolved inorganic nitrogen (DIN) were measured in bog waters along a natural gradient of atmospheric N deposition. Six European bog

  10. 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 t

  11. 137Cs deposition in peat profiles on a raised bog in central Sweden; Forests ecosystems

    Energy Technology Data Exchange (ETDEWEB)

    Rosen, K.; Vinichuk, M.; Galan, P.R.; Johanson, K.J. (Swedish Univ. of Agricultural Sciences, Dept. of Soil Sciences, Uppsala (Sweden))

    2009-06-15

    Distribution of 137Cs 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)

  12. Persistent versus transient tree encroachment of temperate peat bogs: effects of climate warming and drought events

    NARCIS (Netherlands)

    Heijmans, M.M.P.D.; Knaap, Y.A.M.; Holmgren, M.; Limpens, J.

    2013-01-01

    Peatlands store approximately 30% of global soil carbon, most in moss-dominated bogs. Future climatic changes, such as changes in precipitation patterns and warming, are expected to affect peat bog vegetation composition and thereby its long-term carbon sequestration capacity. Theoretical work sugge

  13. Isotope evidence for N2-fixation in Sphagnum peat bogs

    Science.gov (United States)

    Novak, Martin; Jackova, Ivana; Buzek, Frantisek; Stepanova, Marketa; Veselovsky, Frantisek; Curik, Jan; Prechova, Eva

    2016-04-01

    Waterlogged organic soils store as much as 30 % of the world's soil carbon (C), and 15 % of the world's soil nitrogen (N). In the era of climate change, wetlands are vulnerable to increasing temperatures and prolonged periods of low rainfall. Higher rates of microbial processes and/or changing availability of oxygen may lead to peat thinning and elevated emissions of greenhouse gases (mostly CO2, but also CH4 and N2O). Biogeochemical cycling of C and N in peat bogs is coupled. Under low levels of pollution by reactive nitrogen (NO3-, NH4+), increasing N inputs may positively affect C storage in peat. Recent studies in North America and Scandinavia have suggested that pristine bogs are characterized by significant rates of microbial N2 fixation that augments C storage in the peat substrate. We present a nitrogen isotope study aimed at corroborating these findings. We conducted an isotope inventory of N fluxes and pools at two Sphagnum-dominated ombrotrophic peat bogs in the Czech Republic (Central Europe). For the first time, we present a time-series of del15N values of atmospheric input at the same locations as del15N values of living Sphagnum and peat. The mean del15N values systematically increased in the order: input NH4+ (-10.0 ‰) < input NO3- (-7.9 ‰) < peat porewater (-5.6 ‰) < Sphagnum (-5.0 ‰) < shallow peat (-4.2 ‰) < deep peat (-2.2 ‰) < runoff (-1.4 ‰) < porewater N2O (1.4 ‰). Importantly, N of Sphagnum was isotopically heavier than N of the atmospheric input (p < 0.001). If partial incorporation of reactive N from the atmosphere into Sphagnum was isotopically selective, the residual N would have to be isotopically extremely light. Such N, however, was not identified anywhere in the ecosystem. Alternatively, Sphagnum may have contained an admixture of isotopically heavier N from atmospheric N2 (del15N N2 = 0 ‰). We conlude that the N isotope systematics at the two Czech sites is consistent with the concept of significant N2 fixation

  14. Desmid flora from four peat bogs in Serbia

    Directory of Open Access Journals (Sweden)

    Šovran Sanja

    2013-01-01

    Full Text Available The main objective of this paper is to report the desmid taxa identified from four Serbian peat bogs: Pešter, Daić Lake on Mt. Golija, Crvene pode on Mt. Tara and Horgoš. Samples were collected in the period from 2007 to 2011. In total, 220 desmid taxa from 22 genera were identified. The most species-rich genera are Cosmarium (81, Staurastrum (38 and Closterium (31. Of the total number, 66 desmid taxa are new for the Serbian desmid flora. [Projekat Ministarstva nauke Republike Srbije, br. TR 037009

  15. Annual CO2 balance of a temperate bog

    OpenAIRE

    Lund, Magnus; Lindroth, Anders; Christensen, Torben R.; Ström, Lena

    2011-01-01

    Peatlands are generally small sinks for atmospheric CO2. However, the sustainability of this sink functioning is threatened in a changing climate. We measured the CO2 exchange in a temperate bog between August 2005 and July 2006 using the eddy covariance technique. During this period, the CO2 balance was –78.6 ± 20.0 g CO2 m-2 yr-1, which is a lower uptake than others have reported for comparable ecosystems, but in accordance with average Holocene uptake rates. Average winter emissions were s...

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

    Science.gov (United States)

    We compared the N budgets of an ombrotrophic bog and a minerotrophic fen to quantify the importance of denitrification in peatlands and their watersheds. We also compared the watershed upland mineral soils to bog/fen peat; lagg and transition zone peat to central bog/fen peat; an...

  17. 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, Stanley 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

  18. Electrocoagulation treatment of peat bog drainage water containing humic substances.

    Science.gov (United States)

    Kuokkanen, V; Kuokkanen, T; Rämö, J; Lassi, U

    2015-08-01

    Electrocoagulation (EC) treatment of 100 mg/L synthetic wastewater (SWW) containing humic acids was optimized (achieving 90% CODMn and 80% DOC removal efficiencies), after which real peat bog drainage waters (PBDWs) from three northern Finnish peat bogs were also treated. High pollutant removal efficiencies were achieved: Ptot, TS, and color could be removed completely, while Ntot, CODMn, and DOC/TOC removal efficiencies were in the range of 33-41%, 75-90%, and 62-75%, respectively. Al and Fe performed similarly as the anode material. Large scale experiments (1 m(3)) using cold (T = 10-11 °C) PBDWs were also conducted successfully, with optimal treatment times of 60-120 min (applying current densities of 60-75 A/m(2)). Residual values of Al and Fe (complete removal) were lower than their initial values in the EC-treated PBDWs. Electricity consumption and operational costs in optimum conditions were found to be low and similar for all the waters studied: 0.94 kWh/m(3) and 0.15 €/m(3) for SWW and 0.35-0.70 kWh/m(3) and 0.06-0.12 €/m(3) for the PBDWs (large-scale). Thus, e.g. solar cells could be considered as a power source for this EC application. In conclusion, EC treatment of PBDW containing humic substances was shown to be feasible.

  19. 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. PMID:26220310

  20. Bog ground aquifer system as a natural analogue for future redox conditions in flooded underground mines

    International Nuclear Information System (INIS)

    To characterize the future redox milieu caused by natural degradation of wood in flooded mines, the aquifer of a highland bog ground was studied as a natural analogue site. Going from the surface to a depth of one meter in the bog water, the redox potential measured with a platinum electrode changes from 593 mV to -95 mV. From the depth-water analyses and analyses of bog gas extracted from the ground, an Eh value of -119±5 mV could be calculated. Methane and hydrogen sulfide were found in the gas, characterizing the strongly reducing condition in the bog ground. From that, the conclusion for the future mine situation can be drawn that uranium(VI) and arsenic(V) will be reduced and precipitated as U(OH)4 and As2S3. In that way, decontamination of the mine water takes place as a consequence of a natural attenuation process. (author)

  1. Peat bogs in northern Alberta, Canada reveal decades of declining atmospheric Pb contamination

    Science.gov (United States)

    Shotyk, William; Appleby, Peter G.; Bicalho, Beatriz; Davies, Lauren; Froese, Duane; Grant-Weaver, Iain; Krachler, Michael; Magnan, Gabriel; Mullan-Boudreau, Gillian; Noernberg, Tommy; Pelletier, Rick; Shannon, Bob; Bellen, Simon; Zaccone, Claudio

    2016-09-01

    Peat cores were collected from six bogs in northern Alberta to reconstruct changes in the atmospheric deposition of Pb, a valuable tracer of human activities. In each profile, the maximum Pb enrichment is found well below the surface. Radiometric age dating using three independent approaches (14C measurements of plant macrofossils combined with the atmospheric bomb pulse curve, plus 210Pb confirmed using the fallout radionuclides 137Cs and 241Am) showed that Pb contamination has been in decline for decades. Today, the surface layers of these bogs are comparable in composition to the "cleanest" peat samples ever found in the Northern Hemisphere, from a Swiss bog ~ 6000 to 9000 years old. The lack of contemporary Pb contamination in the Alberta bogs is testimony to successful international efforts of the past decades to reduce anthropogenic emissions of this potentially toxic metal to the atmosphere.

  2. Climate-driven expansion of blanket bogs in Britain during the Holocene

    Directory of Open Access Journals (Sweden)

    A. V. Gallego-Sala

    2015-10-01

    Full Text Available Blanket bog occupies approximately 6 % of the area of the UK today. The Holocene expansion of this hyperoceanic biome has previously been explained as a consequence of Neolithic forest clearance. However, the present distribution of blanket bog in Great Britain can be predicted accurately with a simple model (PeatStash based on summer temperature and moisture index thresholds, and the same model correctly predicts the highly disjunct distribution of blanket bog worldwide. This finding suggests that climate, rather than land-use history, controls blanket-bog distribution in the UK and everywhere else. We set out to test this hypothesis for blanket bogs in the UK using bioclimate envelope modelling compared with a database of peat initiation age estimates. We used both pollen-based reconstructions and climate model simulations of climate changes between the mid-Holocene (6000 yr BP, 6 ka and modern climate to drive PeatStash and predict areas of blanket bog. We compiled data on the timing of blanket-bog initiation, based on 228 age determinations at sites where peat directly overlies mineral soil. The model predicts large areas of northern Britain would have had blanket bog by 6000 yr BP, and the area suitable for peat growth extended to the south after this time. A similar pattern is shown by the basal peat ages and new blanket bog appeared over a larger area during the late Holocene, the greatest expansion being in Ireland, Wales and southwest England, as the model predicts. The expansion was driven by a summer cooling of about 2 °C, shown by both pollen-based reconstructions and climate models. The data show early Holocene (pre-Neolithic blanket-bog initiation at over half of the sites in the core areas of Scotland, and northern England. The temporal patterns and concurrence of the bioclimate model predictions and initiation data suggest that climate change provides a parsimonious explanation for the early Holocene distribution and later

  3. 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

  4. Functional diversity, succession, and human-mediated disturbances in raised bog vegetation.

    Science.gov (United States)

    Dyderski, Marcin K; Czapiewska, Natalia; Zajdler, Mateusz; Tyborski, Jarosław; Jagodziński, Andrzej M

    2016-08-15

    Raised and transitional bogs are one of the most threatened types of ecosystem, due to high specialisation of biota, associated with adaptations to severe environmental conditions. The aim of the study was to characterize the relationships between functional diversity (reflecting ecosystem-shaping processes) of raised bog plant communities and successional gradients (expressed as tree dimensions) and to show how impacts of former clear cuts may alter these relationships in two raised bogs in 'Bory Tucholskie' National Park (N Poland). Herbaceous layers of the plant communities were examined by floristic relevés (25m(2)) on systematically established transects. We also assessed patterns of tree ring widths. There were no relationships between vegetation functional diversity components and successional progress: only functional dispersion was negatively, but weakly, correlated with median DBH. Lack of these relationships may be connected with lack of prevalence of habitat filtering and low level of competition over all the successional phases. Former clear cuts, indicated by peaks of tree ring width, influenced the growth of trees in the bogs studied. In the bog with more intensive clear cuts we found more species with higher trophic requirements, which may indicate nutrient influx. However, we did not observe differences in vegetation patterns, functional traits or functional diversity indices between the two bogs studied. We also did not find an influence of clear cut intensity on relationships between functional diversity indices and successional progress. Thus, we found that alteration of the ecosystems studied by neighbourhood clear cuts did not affect the bogs strongly, as the vegetation was resilient to these impacts. Knowledge of vegetation resilience after clear cuts may be crucial for conservation planning in raised bog ecosystems.

  5. Hydrologic analysis of the wetland habitat of the federally threatened bog turtle

    OpenAIRE

    Brennan, Kelly E.; O'Leary, Daniel J.; Buckley, Stephen P.

    2001-01-01

    Protecting the natural environment while fostering local development is one of the main challenges that engineers face today. New species are added to the federally threatened and endangered species lists as their habitats are altered or destroyed by development. The bog turtle (clemmys muhlenbergii) is threatened by new development that damages not only its wetland habitat, but the upland areas that store and discharge water into the wetlands. The bog turtle is one of the smallest North Amer...

  6. Functional diversity, succession, and human-mediated disturbances in raised bog vegetation.

    Science.gov (United States)

    Dyderski, Marcin K; Czapiewska, Natalia; Zajdler, Mateusz; Tyborski, Jarosław; Jagodziński, Andrzej M

    2016-08-15

    Raised and transitional bogs are one of the most threatened types of ecosystem, due to high specialisation of biota, associated with adaptations to severe environmental conditions. The aim of the study was to characterize the relationships between functional diversity (reflecting ecosystem-shaping processes) of raised bog plant communities and successional gradients (expressed as tree dimensions) and to show how impacts of former clear cuts may alter these relationships in two raised bogs in 'Bory Tucholskie' National Park (N Poland). Herbaceous layers of the plant communities were examined by floristic relevés (25m(2)) on systematically established transects. We also assessed patterns of tree ring widths. There were no relationships between vegetation functional diversity components and successional progress: only functional dispersion was negatively, but weakly, correlated with median DBH. Lack of these relationships may be connected with lack of prevalence of habitat filtering and low level of competition over all the successional phases. Former clear cuts, indicated by peaks of tree ring width, influenced the growth of trees in the bogs studied. In the bog with more intensive clear cuts we found more species with higher trophic requirements, which may indicate nutrient influx. However, we did not observe differences in vegetation patterns, functional traits or functional diversity indices between the two bogs studied. We also did not find an influence of clear cut intensity on relationships between functional diversity indices and successional progress. Thus, we found that alteration of the ecosystems studied by neighbourhood clear cuts did not affect the bogs strongly, as the vegetation was resilient to these impacts. Knowledge of vegetation resilience after clear cuts may be crucial for conservation planning in raised bog ecosystems. PMID:27110977

  7. 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}.

  8. Anthropogenic degradation of mountainous raised bogs. Case study of the Polish Carpathians

    Science.gov (United States)

    Lajczak, Adam

    2016-04-01

    Publications on the human impact on peat bogs pay a lot of attention to peat erosion, peat burning and changes in the physical and chemical properties of peat deposits that indicate pollution in the environment, but a more detailed analysis of current changes in the peat bog relief as a result of peat deposit extraction and drying is omitted. Compared to other areas of the world, the level of knowledge on anthropogenic changes in the relief of peat bogs in some areas of Poland may be considered advanced. This applies not only to peat bogs in northern Poland but also southern Poland, where peat bogs in the Carpathians and the Sudetes are also found. The best analyzed peat bogs in southern Poland are the raised bogs in the Orawsko-Nowotarska Basin (Western Carpathians) and in valleys in the Bieszczady Mts. (Eastern Carpathians). Both areas are impacted by deep precipitation shadow. The purpose of this paper is: (1) to assess the rate of shrinkage in the surface area of peat domes in the mentioned areas, (2) to describe the rate of growth in the surface area of older and younger post-peat areas, (3) to explain current changes in peat bogs morphology, (4) to explain changes in water retention in peat deposit, (5) to separate phases in peat bogs relief changes. With that in mind, the direction and rate of change of landforms typical of younger post-peat areas, such as peat extraction scarps, post-extraction hollows, drainage systems including ditches and regulated stream channels, were analyzed. A special emphasis was placed on the period of time when the restoration of such areas has taken place. The paper is based on an analysis of maps produced over the last 230 years as well as on aerial photographs taken since 1965 and on LiDAR data. Fieldwork included the geomorphological and hydrographic mapping of specified landforms within peat bogs using GPS methods. In period prior to human activity peat domes were larger than today and were surrounded by lagg fens and were

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

    OpenAIRE

    S.J. Scarlett; J.S. Price

    2013-01-01

    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 veget...

  10. 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.

  11. Small scale controls of greenhouse gas release under elevated N deposition rates in a restoring peat bog in NW Germany

    OpenAIRE

    S. Glatzel; I. Forbrich; Krüger, C.; Lemke, S.; Gerold, G.

    2008-01-01

    In Central Europe, most bogs have a history of drainage and many of them are currently being restored. Success of restoration as well as greenhouse gas exchange of these bogs is influenced by environmental stress factors as drought and atmospheric nitrogen deposition. We determined the methane and nitrous oxide exchange of sites in the strongly decomposed center and less decomposed edge of the Pietzmoor bog in NW Germany in 2004. Also, we examined the methane and nitrous oxide exchange of mes...

  12. The hydrology of natural and artificial bog pools

    Science.gov (United States)

    Holden, Joseph; Turner, Ed; McKenzie, Rebecca; Baird, Andy; Billett, Mike; Chapman, Pippa; Dinsmore, Kerry; Dooling, Gemma

    2016-04-01

    Twelve bog pools were monitored over a 3.5-year period (2012-2015) in the Cross Lochs blanket peatland in the Flow Country of northern Scotland. Six pools were located in a natural pool complex while the other six were in an adjacent area where the peat had been ditched in the 1970s. The ditches had been subsequently dammed with peat in 2002 resulting in dozens of artificial pools along each ditch, with one pool upslope of each dam. The natural pools ranged in area from 15 m2 to 850 m2, while the artificial pools are a more uniform size at c.3 - 4 m2. Following a dry first summer, water levels in the 12 pools were lower throughout the subsequent winter and spring than they were in proceeding years showing strong inter-annual variability in pool levels even for winter months. Over the three year study, water level fluctuations in the natural pools were very different to those in the artificial pools. The natural pools showed subdued responses to rainfall and, after rainfall, slow falls in water level dominated by evaporation; the hydraulic conductivity of the peat was very low at depths of 30 and 50 cm below the peat surface around the pools (median values of 2.49 × 10-5 and 1.09 × 10-5 cm s-1 respectively). The artificial pools had much larger monthly interquartile ranges of water levels and a greater rise and fall of pool water level in response to each individual rainfall event compared with the natural pools. Thus the biogeochemistry and carbon cycling processes that occur within the natural pools is not likely to be replicated in the artificial pools as their hydrological behaviour is quite different. Slope position was a factor in terms of hydrological response of pools with those further downslope having higher relative water levels for longer periods of time compared to upslope pools. Thus we anticipate that local biogeochemical processes in and around bog pools may be impacted by slope position and by whether they are natural pools or artificial pools

  13. The growth of permafrost-free bogs at the southern margin of permafrost, 1947-2010

    Science.gov (United States)

    Quinton, W. L.; Sonnentag, O.; Connon, R.; Chasmer, L.

    2013-12-01

    In the high-Boreal region of NW Canada, permafrost occurs predominantly in the form of tree-covered peat plateaus within a permafrost-free and treeless terrain dominated by flat bogs. This region is experiencing unprecedented rates of thaw. Over the last several decades, such thaw has significantly expanded the permafrost-free, treeless terrain at the expense of the plateaus. This rapid change in land-cover has raised concerns over its impact on northern water resources, since remotely sensed data and ground observations indicate that the two major land-covers in this region have very different hydrological functions. Peat plateaus have a limited capacity to store water, a relatively large snowmelt water supply and hydraulic gradients that direct excess water into adjacent permafrost-free wetlands. As such, the plateaus function primarily as runoff generators. Plateaus also obstruct and redirect water movement in adjacent wetlands since the open water surfaces of the latter occupy an elevation below the permafrost table. By contrast, bogs are primarily water storage features since they are surrounded by raised permafrost and therefore less able to exchange surface and near-surface flows with the basin drainage network. Accurate estimate of the permafrost and permafrost-free areas is needed for accurate predictions of basin runoff and storage. This study examines the perimeter-area characteristics of bogs and permafrost plateaus, using fractal geometry as a basis for quantifying these properties. Image analyses are applied to aerial photographs and satellite imagery of Scotty Creek, NWT over the period 1947-2010. Preliminary analyses suggest that the expanding bogs and shrinking permafrost plateaus behave as fractals, meaning that their perimeter-area characteristics can be described by simple power equations. The area-frequency characteristics of bogs and plateaus have a hyperbolic distribution with relatively few large bogs and plateaus and numerous small ones

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

    International Nuclear Information System (INIS)

    135Cs 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 (134Cs) 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 (Kd) values of radiocesium increased as a function of sampling depth. The highest Kd 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 Kd values of 133Cs in surface Sphagnum moss, peat and gyttja samples were one order of magnitude higher than the Kd values obtained using the batch method. The highest in situ Kd 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 the sorption

  15. 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

  16. 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.

  17. 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.

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

    Science.gov (United States)

    Liu, Shu-Xun; Yang, Hang-Yu; Li, Si-Yu; Zhang, Jia-Yue; Li, Teng; Zhu, Bao-Qing; Zhang, Bo-Lin

    2015-01-01

    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.

  19. Peat Bogs as Hotspots for Organoarsenical Formation and Persistence.

    Science.gov (United States)

    Mikutta, Christian; Rothwell, James J

    2016-04-19

    Peatlands have received significant atmospheric inputs of As and S since the onset of the Industrial Revolution, but the effect of S deposition on the fate of As is largely unknown. It may encompass the formation of As sulfides and organosulfur-bound As, or the indirect stimulation of As biotransformation processes, which are presently not considered as important As immobilization pathways in wetlands. To investigate the immobilization mechanisms of anthropogenically derived As in peatlands subjected to long-term atmospheric pollution, we explored the solid-phase speciation of As, Fe, and S in English peat bogs by X-ray absorption spectroscopy. Additionally, we analyzed the speciation of As in pore- and streamwaters. Linear combination fits of extended X-ray absorption fine structure (EXAFS) data imply that 62-100% (average: 82%) of solid-phase As (Astot: 9-92 mg/kg) was present as organic As(V) and As(III). In agreement with appreciable concentrations of organoarsenicals in surface waters (pH: 4.0-4.4, Eh: 165-190 mV, average Astot: 1.5-129 μg/L), our findings reveal extensive biotransformation of atmospheric As and the enrichment of organoarsenicals in the peat, suggesting that the importance of organometal(loid)s in wetlands subjected to prolonged air pollution is higher than previously assumed. PMID:27034028

  20. 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

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

    International Nuclear Information System (INIS)

    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 210Pb, and artificial radioisotopes (125Sb, 134Cs, 137Cs, 241Am) were determined using low-level γ-spectrometry. In addition, the activities of 238Pu and 239,240Pu were determined by radiochemical separation and α-spectrometry. 14C and excess 210Pb 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. 125Sb, 241Am, 238Pu and 239,240Pu 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 14C and 210Pb 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.)

  2. 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 rea

  3. 77 FR 2970 - Notice of Intent To Prepare an Environmental Assessment for the Proposed Elba BOG Compressor...

    Science.gov (United States)

    2012-01-20

    ... horsepower electric-motor driven reciprocating gas compressor; flow metering modifications; underground... Elba BOG Compressor Project and Request for Comments on Environmental Issues; Southern LNG Company, L.L... Environmental Assessment (EA) that will discuss the environmental impacts of the Elba BOG Compressor...

  4. Encroachment of woody species on a drained transitional peat bog in ‘Mszar Bogdaniec’ nature reserve (Western Poland

    Directory of Open Access Journals (Sweden)

    Dyderski Marcin K.

    2015-09-01

    Full Text Available One of the most important threats for open peat bog ecosystems is encroachment of woody species, which causes transformation of habitat conditions and leads to retreat of specialised species. Drainage increases the rate of succession. The aim of study is the assessment of human-accelerated succession in a transitional bog. The study was conducted in ‘Mszar Bogdaniec’ nature reserve (W Poland. The structure of vegetation and tree stands was described and compared using ordination methods. Near the peat bog border, tree stands of Betula pubescens developed. Towards the middle part of the peat bog, the number, cover and height of trees decreased. The central part of the peat bog was covered by Sphagno recurvi–Eriophoretum vaginati in dryer parts and Sphagno recurvi–Eriophoretum angustifolii in wetter parts. The study showed that the successional sequence in these conditions differs from the classical bog succession scheme. Despite high propagule pressure of Pinus sylvestris, the most important woody species was B. pubescens, which performed better than other species. Erechtites hieracifolia, an alien invasive herb species, which previously was rarely recorded in bogs, appeared when the bog was dried by drainage. In this study, it reached high frequency and abundance, which shows that it may be a next serious threat to disturbed wetland ecosystems.

  5. 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.

  6. North-West European bogs show that Little Ice Age climate changes may have been driven by changes in solar activity

    NARCIS (Netherlands)

    Mauquoy, D.; Geel, van B.; Blaauw, M.; Plicht, van der J.; Berendse, F.

    2001-01-01

    Bog mosses (Sphagnum species) are sensitive to the position of local water-tables on intact raised peat bogs. These peat bogs are rain-fed, receiving all their water through precipitation alone. After death, the mosses are remarkably well preserved, since they are resistant to decay, and micro-organ

  7. Hydrology controls methane and nitrous oxide fluxes in swamp and bog forests

    Science.gov (United States)

    Mander, Ülo; Pärn, Jaan; Maddison, Martin; Soosaar, Kaido; Salm, Jüri-Ott; Sohar, Kristina; Teemusk, Alar

    2016-04-01

    We used data from a global soil, and N2O and CH4 gas sampling campaign. The objective was to analyse N2O and CH4 emissions related to peat conditions in swamp and bog forests. Altogether, we studied 21 swamp and bog forest sites under various climates: 3 alder swamps and 3 artificially drained bog pine forests in Estonia (Jan.-Dec. 2009), 2 bog forests in Transylvania/Romania (Apr. 2012 & June 2014), 3 cypress swamps in the Everglades (Apr. & Dec. 2013), 2 bog forests in West Siberia (July 2013) and a bog forest in Tasmania (Jan.-Feb. 2014). The N2O and CH4 effluxes were measured during 5-6 days with 8-10 opaque static chambers per site. Soil samples were taken for further analysis of pHKCl, NO3-N, NH4-N, soluble P, K, Ca and Mg, totN and C. Groundwater was measured from sampling wells. The most significant independent factor for site average CH4 fluxes was groundwater depth - an exponential relationship; R2=0.42; p=0.0007; n=21. The N2O fluxes showed a decreasing (power) relationship with the C/N ratio - R2=0.53; pgas fluxes was largest at the more favourable conditions - at optimal water table (+5 to -20cm) for CH4 and at low C/N for N2O. The results agree with previous literature but they are the first to draw such conclusions from a global campaign following a uniform protocol.

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

    DEFF Research Database (Denmark)

    Hultman, Jenni; Waldrop, Mark P.; Mackelprang, Rachel;

    2015-01-01

    , 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...... activity in intact, let alone in thawing, permafrost. Molecular approaches have recently revealed the identities and functional gene composition of microorganismsin some permafrost soils(2-4) and a rapid shift in functional gene composition during short-term thaw experiments(3). However, the fate...

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

    DEFF Research Database (Denmark)

    Villa, Chiara; Lynnerup, Niels

    2012-01-01

    (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...... and inhumated ancient human skeletal remains, and fossil animal bones. Knowledge of the typical HU range for the different tissues in mummies may help to avoid misinterpretation of increased or reduced radiodensity as evidence of paleopathological conditions. Finally, we demonstrate the practical benefit...

  10. 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)

  11. 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

  12. 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

    The chemistry of wet Spodosols (Aquods) differs from well-drained Spodosols. Two different hypotheses have been suggested to explain the contrasting genesis of wet spodic horizons. This study attempted to determine whether Aquods at a Danish peat-bog wetland site are a result of (i) in situ...

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

    International Nuclear Information System (INIS)

    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

  14. Expansion of invasive species on ombrotrophic bogs: desiccation or high N deposition?

    NARCIS (Netherlands)

    Tomassen, H.B.M.; Smolders, A.J.P.; Limpens, J.; Lamers, L.P.M.; Roelofs, J.G.M.

    2004-01-01

    1. In many ombrotrophic bog areas the invasion of grass (e.g. Molinia caerulea) and tree (e.g. Betula pubescens) species has become a major problem. We investigated whether the invasion of such species is due to high atmospheric nitrogen (N) deposition by conducting a fertilization experiment. 2. Th

  15. Diurnal and seasonal variation of carbon dioxide exchange from a former true raised bog.

    NARCIS (Netherlands)

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

    1998-01-01

    Carbon dioxide exchange was measured, using the eddy covariance technique, during a one and a half year period in 1994 and 1995. The measurements took place over a former true raised bog, characterized by a shallow peat layer and a vegetation dominated by Molinia caerulea. The growing season extende

  16. Pollution of bogs in Tomsk region (Western Siberia, Russia as an indicator of sustainable development

    Directory of Open Access Journals (Sweden)

    A.M Mezhibor

    2014-10-01

    Full Text Available Wetlands play a key role in the climatic balance of our planet. Thus, their protection from anthropogenic pollution is an important target for sustainable development of environment. Wetlands have a special significance for the Siberian region of Russia where they take great territories. Peat bogs, being unique ecosystems among wetlands, have properties to save the history of atmospheric pollution. The particularity of peat bogs is determined by their nutrition - they receive chemical elements mostly from the atmosphere. Some peat bogs in Siberia (Tomsk region, Russia were studied to determine the degree of environment pollution during the last century and the change of geochemical composition of peat in time. These studies determined the increase of pollution in the region from the middle of 20th century because of the sharp industrial development. The data on the pollution of peat bogs allow concluding that the geochemical peculiarities of different parts of Tomsk region influenced by different types of industry: nuclear facility, coal-burning power stations and oil refineries. This method can be used together with other methods implemented for the detection of anthropogenic pollution and the results can be used as indicative parameters in environmental change. The results of the studies can be used for the development of recommendations in the decrease of the industry influence for the sustainable development of Siberian region.Keywords: upland peat, air pollution, Tomsk region, indicators of sustainable development

  17. Effects of climate change and human activities on a Swedish raised bog

    NARCIS (Netherlands)

    M. van der Linden

    2005-01-01

    We determined the effects of climate change and human activities on the species composition of ombrotrophic (rain-fed) peat bogs by analyzing pollen and macrofossils. We used 14C AMS wiggle-match dating (1) to obtain a precise chronology. Thermophilous plant species in the microfossil record provide

  18. Field evidence for buoyancy-driven water flow in a Sphagnum dominated peat bog

    NARCIS (Netherlands)

    Adema, E.B.; Baaijens, G. J.; van Belle, J.; Rappoldt, C.; Grootjans, A. P.; Smolders, A. J. P.

    2006-01-01

    Nocturnal buoyancy-driven water flow in bogs is proposed as a mechanism to replenish the nutrient availability in the top of the acrotelm. In an earlier paper, we provided evidence for buoyancy-driven water flow on theoretical and experimental grounds. In this paper, field evidence is given for the

  19. 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.)

  20. Small is beautiful: why microtopography should be included in bog hydrology

    Science.gov (United States)

    Appels, Willemijn; van der Ploeg, Martine; Oosterwoud, Marieke; Cirkel, Gijsbert; van der Zee, Sjoerd; Witte, Jan-Philip

    2014-05-01

    Microtopography can have a large effect on flow processes at the soil surface and the composition of soil water. In peat areas, microtopography is shaped by differences in species, the growth rate and transpiration of the vegetation, and the amount of water flowing from higher areas. Microtopography is often represented by a roughness parameter in hillslope hydrological models. In areas without a strong topographical gradient however, microtopography may be underestimated when accumulated in a single parameter, especially in the presence of shallow groundwater systems. In this study, we review the intricate relationships between microtopography, surface runoff, and ecohydrology in systems featuring shallow water tables. In an analogy to surface runoff, the hydrology of a raised bog can be described as a combination of open water flow on a saturated medium, instead of the traditional acrotelm-catotelm concept that only acknowledges the saturated medium. We explored water flow through the microtopography of a raised bog with a simple conceptual model that accounts explicitly for microtopographic features and the changing flow directions these may cause. With this approach we were able to investigate the activation of fast flow paths on different areas of the bog as a function of their wetness level and bog-specific morphological features, such as hummocks and hollows. Our type of approach could be used to improve the understanding of the spatial and temporal variability of rainfall-runoff responses on raised bogs. In addition, similar approaches could be used to investigate how various runoff regimes affect the mixing of water with different chemical signatures, another driver of variations of the occurrence of plant species.

  1. Influencing factors and stability of BOG generation in LNG receiving terminal%LNG接收站BOG蒸发量的影响因素及稳定性

    Institute of Scientific and Technical Information of China (English)

    李亚军; 夏岩

    2012-01-01

    针对某一液化天然气(LNG)接收站存在的蒸发气体(BOG)量波动大、BOG燃烧排放及单位BOG处理量能耗高等问题,分析了BOG蒸发量的主要影响因素及维持BOG量稳定性的可行性.提出了对现有操作进行基于储罐操作压力调控的优化方案,优化操作后BOG蒸发量稳定性提高,避免了BOG燃烧排放,同时降低了工艺能耗,增加了经济效益.%In allusion to the problems existing in BOG system of one LNC receiving terminal in China, such as great fluctuation of BOG generation, high energy consumption of BOG processing and the resource waste of BOG flare emission and so on, the parameters that affect BOG generation volume and the feasibility of maintaining BOG generation stability were analyzed. The existing operation was optimized by using chemical process simulation software. The optimization concentrated on the regulation of pressure of LNG tanks. The stability of BOG generation in optimized operation was improved and BOG flare emission was avoided, which reduced the energy consumption of BOG processing while increased economic benefit.

  2. Fire, Flood, and Famine: Pattern and Process in a Lakeside Bog at Missisquoi National Wildlife Refuge 1988

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Maquam Bog contains Vermonts largest populations of pitch pine, rhodora and chain fern, a statethreatened species. Dendrochronological methods were used to examine...

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

    Science.gov (United States)

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

    2015-09-01

    (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 (Kd) values of radiocesium increased as a function of sampling depth. The highest Kd 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 Kd values of (133)Cs in surface Sphagnum moss, peat and gyttja samples were one order of magnitude higher than the Kd values obtained using the batch method. The highest in situ Kd 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. PMID:26010098

  4. Methane cycling in peat bogs: Environmental relevance of methano-Trophs revealed by microbial lipid chemistry. LPP Contribution Series (35)

    OpenAIRE

    van Winden, J.F.

    2011-01-01

    Global warming is continuing without delay and this is caused by the accumulation of greenhouse gases in the atmosphere. Methane is a strong greenhouse gas, 25 times stronger compared to CO2. The increase in methane concentrations in the atmosphere is largely the result of human influences, but there are also natural sources of methane, as for instance peat bogs. Peat bogs store an enormous amount of carbon, three times as much as tropical rain forests, yet are also responsible for about 10% ...

  5. Methanotrophic activity and diversity in different Sphagnum magellanicum dominated habitats in the southernmost peat bogs of Patagonia

    OpenAIRE

    N. Kip; Fritz, C.; Langelaan, E. S.; Pan, Y.; L. Bodrossy; Pancotto, V.; M. S. M. Jetten; Smolders, A.J.P.; Camp, H. J. M.

    2012-01-01

    Sphagnum peatlands are important ecosystems in the methane cycle. Methanotrophs living inside the dead hyaline cells or on the Sphagnum mosses are able to act as a methane filter and thereby reduce methane emissions. We investigated in situ methane concentrations and the corresponding activity and diversity of methanotrophs in different Sphagnum dominated bog microhabitats. In contrast to the Northern Hemisphere peat ecosystems the temperate South American peat bogs are domi...

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

    International Nuclear Information System (INIS)

    79Se is among the most important long lived radionuclides in spent nuclear fuel and selenite, SeO32−, 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 (Kd) values of selenite decreased as a function of sampling depth and highest Kd 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 Kd 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 SeO32− removal from simulated bog water. • Bacteria isolated from the bog samples removed selenite from the solution. • Bacteria affect the removal of SeO32− 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

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

    OpenAIRE

    Beyer, C.; Höper, H.

    2014-01-01

    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 ...

  8. 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 archaeological samples, the second part included the characterisation of the dyes detected in the whole series of the Early Iron Age textiles and the interpretation of the dyeing technology. Natural organic dyes were found from the three main categories of natural dyes, hence throwing new light on the use...... 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....

  9. 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.

  10. Variation in methanotroph-related proxies in peat deposits from Misten Bog, Hautes-Fagnes, Belgium

    OpenAIRE

    van Winden, Julia F.; Talbot, Helen M.; De Vleeschouwer, François; Reichart, Gert-Jan; Sinninghe Damsté, Jaap S.

    2012-01-01

    Methane emissions from peat bogs are strongly reduced by aerobic methane oxidising bacteria (methanotrophs) living in association with Sphagnum spp. Field studies and laboratory experiments have revealed that, with increasing water level and temperature, methanotrophic activity increases. To gain a better understanding of how longer term changes in methanotrophic activity are reflected in methanotroph biomarkers, a peat record (0–100 cm) from the Hautes-Fagnes (Belgium) encompassing the past ...

  11. Contributions to the knowledge of flora and vegetation of peat bog from Bihorului Mountains (NW Romania

    Directory of Open Access Journals (Sweden)

    Petru BURESCU

    2010-11-01

    Full Text Available The oligotrophic peat bog of Bihorului Mountains are quartered in the valleys with northern exposure, of siliceous substrate, forming habitats with high conservation value, which are home to over 10 rare relict species. The phytocoenoses of the associations Sphagnetum magellanici, Sphagno cuspidati – Rhynchosporetum albae, Caricetum limosae were analyzed by us in terms of floristic composition, ecological spectra of the type of life forms and floristic elements, in terms of chart ecological factors: moisture, soil temperature and chemical reaction.

  12. Functional Diversity of Boreal Bog Plant Species Decreases Seasonal Variation of Ecosystem Carbon Sink Function

    Science.gov (United States)

    Korrensalo, A.

    2015-12-01

    Species diversity has been found to decrease the temporal variance of productivity of a plant community, and diversity in species responses to environmental factors seems to make a plant community more stable in changing conditions. Boreal bogs are nutrient poor peatland ecosystems where the number of plant species is low but the species differ greatly in their growth form. In here we aim to assess the role of the variation in photosynthesis between species for the temporal variation in ecosystem carbon sink function. To quantify the photosynthetic properties and their seasonal variation for different bog plant species we measured photosynthetic parameters and stress-inducing chlorophyll fluorescence of vascular plant and Sphagnum moss species in a boreal bog over a growing season. We estimated monthly gross photosynthesis (PG) of the whole study site based on species level light response curves and leaf area development. The estimated PG was further compared with a gross primary production (GPP) estimate measured by eddy covariance (EC) technique. The sum of upscaled PG estimates agreed well with the GPP estimate measured by the EC technique. The contributions of the species and species groups to the ecosystem level PG changed over the growing season. The sharp mid-summer peak in sedge PG was balanced by more stable PG of evergreen shrubs and Sphagna. Species abundance rather than differences in photosynthetic properties between species and growth forms determined the most productive plants on the ecosystem scale. Sphagna had lower photosynthesis and clorophyll fluorescence than vascular plants but were more productive on the ecosystem scale throughout the growing season due to their high areal coverage. These results show that the diversity of growth forms stabilizes the seasonal variation of the ecosystem level PG in an ombrotrophic bog ecosystem. This may increase the resilience of the ecosystem to changing environmental conditions.

  13. Recent atmospheric dust deposition in an ombrotrophic peat bog from the Himalaya

    International Nuclear Information System (INIS)

    Ombrotrophic peat bogs, are important natural archives for records of atmospheric pollution by heavy metals. As continental geochemical archives in exclusively recording past atmospheric deposition, they have the unique advantage of a wide global distribution relative to ice cores. Mean annual depositional fluxes of these elements across the peat bog surface are mainly controlled by the atmospheric concentration and total rainfall. To characterize historical trends in the extent and sources of environmental pollution, a peat core from the Pinder Valley (30.05°N, 79.93°E) in the Himalaya was collected. 210Pb and 137Cs radionuclides, with well-define fallout records are used for dating the past 150 years of peat accumulation. Beyond this, 14C AMS dating was used for dating the core. The activities of radionuclides were measured using High Purity Germanium Gamma detector and the concentrations of refractory lithogenic (AI, Ca, Fe, Mn, V and Ti) and trace elements (Pb, Cu, Zn, Co, Ni, Mo, Cr, Sr and Ba) using ICP-MS. In this study, the historical records obtained from the peat bog from the Himalaya extending up to 5000 years show evidence for rising anthropogenic inputs of trace metals to the remote high altitude atmosphere since 1970s, resulting largely from fossil fuel consumption, non-ferrous metal production, coal-powered electricity generation and fertilizer use. Geochemistry of peat and the analysis of past environmental changes will be presented. (author)

  14. Sensitivity of carbon gas fluxes to weather variability on pristine, drained and rewetted temperate bogs

    Directory of Open Access Journals (Sweden)

    Z. Urbanová

    2013-05-01

    Full Text Available Climate change is considered to alter the functioning of boreal peatland ecosystems, but the vulnerability of pristine, rewetted and drained peatlands to climate change in temperate regions is unknown. We measured carbon (C gas exchange during wet (2009 and dry (2010 growing periods in pristine, drained and rewetted sites in mountain bogs in the Bohemian Forest (Czech Republic. Wetter lawns with sedges and drier habitats dominated by ericaceous shrubs were distinguished and studied at each site. Methane (CH4 emissions, which decreased in the order pristine > rewetted > drained, were generally lower during the 2010 growing period than in 2009 as a consequence of a drought. During the drought in 2010, photosynthesis (PG in the drier habitats with shrub vegetation increased on pristine and rewetted sites, while total respiration (RECO remained the same. Communities dominated by sedges maintained similar rates of PG and RECO during both growing periods. Generally, this led to higher C accumulation during the drought on pristine and rewetted bogs. At the drained bog site, the decreased water table (WT during the drought led to increased PG and RECO, such that the net C accumulation was similar in the two years. Drained peatlands may be more threatened by future climate change than pristine or rewetted peatlands because of their limited buffering capacity for decreased WT. In the case of further decreases in WT, they could lose the peatland vegetation and functions that have partly persisted through decades of drainage.

  15. Late Holocene palaeoclimate variability: The significance of bog pine dendrochronology related to peat stratigraphy. The Puścizna Wielka raised bog case study (Orawa - Nowy Targ Basin, Polish Inner Carpathians)

    Science.gov (United States)

    Krąpiec, Marek; Margielewski, Włodzimierz; Korzeń, Katarzyna; Szychowska-Krąpiec, Elżbieta; Nalepka, Dorota; Łajczak, Adam

    2016-09-01

    The results of dendrochronological and palynological analyses of subfossil pine trees occurring in the peat deposits of the Puścizna Wielka raised bog (Polish Carpathians, Southern Poland) - the only site with numerous subfossil pine trees in the mountainous regions of Central Europe presently known - indicate that the majority of the tree populations grew in the peat bog during the periods ca 5415-3940 cal BP and 3050-2560 cal BP. Several forestless episodes, dated to 5245-5155 cal BP, 4525-4395 cal BP and 3940-3050 cal BP, were preceded by tree dying-off phases caused by an extreme periodical increase in humidity and general climate cooling trends. These events are documented based on analyses of pollen and non-pollen palynomorph assemblages, dendrochronological analyses of the trees, as well as numerous radiocarbon datings of the sediment horizons occurring within the peat bog profile. The phases of germinations, and, in turn, of tree and shrub invasions of the peat bog areas have been closely connected to drying and occasional warming of the regional climate. The last of the forestless periods began about 2600 years ago and continued up to the very recent times. Currently, as a result of desiccation of the peat bog and the lowering of the groundwater level (due to improved water drainage system), pine trees have returned the peat bog again. These results demonstrate that studies of subfossil bog-pine trees are quite effective in documenting and reconstructing periods of humidity fluctuation that occurred within the Carpathian region over the last several millennia.

  16. Impact of catchment degree on peat properties in peat deposits of eutrophic bog

    Science.gov (United States)

    Inisheva, L. I.; Golubina, O. A.; Rodikova, A. V.; Shinkeeva, N. A.; Bubina, A. B.

    2010-05-01

    Fundamental works of many investigators show that according to the biophysical properties peat deposit (PD) is divided into 2 layers: active and inert. It is interesting to analyze the supposed changes in PD of eutrophic bog according to different data (physical, chemical and biological). The researches were carried out at two plots of one bog (points 1 and 2, positions 56° 21' NL, 84° 47' EL, Russia, Siberia). Agricultural afforestation (pine planting) was made at one of them (point 2) 60 years ago. Now this plot is absolutely identical in ground cover to 1 point, but other conditions are significantly changed. In spring bog water level is at the depth of 20cm at 2 point (at 1 point it is near water face), it lows up to 53 cm during summer time (at 1 point - up to 37 cm). According to redox conditions zone of anoxic-oxic conditions reaches meter depth at 2 points. PDs don't significantly differ in activity of ammonifiers but in activity of cellulose-lytic aerobic microflora it follows that it is more active at 2 point in PD active layer. In spite of good aeration, more favorable conditions were created also for anaerobic cellulose-fermenting microflora in PD of 2 point in comparison with 1 one. Activity analysis of denitrifying agents and microflora of other physiological groups also showed high activity of biota at the plot with afforestation amelioration. This fact was confirmed by high coefficient of mineralization. Time of drainage effect created by afforestation amelioration influenced group composition of peat organic matter which builds up PD of examined plots. According to fractional and group composition data fracture of hard-to-hydrolyze organic matters decreased during the process of microflora activating at the plot with afforestation amelioration but FA content increased. Fractional composition of nitrogen showed that content of mineral nitrogen compounds definitely increased. Thus, 60 years of surface drainage influenced composition change of peat

  17. Photosynthetic properties of boreal bog plant species and their contribution to ecosystem level carbon sink

    Science.gov (United States)

    Korrensalo, Aino; Hájek, Tomas; Alekseychik, Pavel; Rinne, Janne; Vesala, Timo; Mehtätalo, Lauri; Mammarella, Ivan; Tuittila, Eeva-Stiina

    2016-04-01

    Boreal bogs have a low number of plant species, but a large diversity of growth forms. This heterogeneity might explain the seasonally less varying photosynthetic productivity of these ecosystems compared to peatlands with vegetation consisting of fewer growth forms. The differences in photosynthetic properties within bog species and phases of growing season has not been comprehensively studied. Also the role of different plant species for the ecosystem level carbon (C) sink function is insufficiently known. We quantified the seasonal variation of photosynthetic properties in bog plant species and assessed how this variation accounts for the temporal variation in the ecosystem C sink. Photosynthetic light response of 11 vascular plant and 8 Sphagnum moss species was measured monthly over the growing season of 2013. Based on the species' light response parameters, leaf area development and areal coverage, we estimated the ecosystem level gross photosynthesis rate (PG) over the growing season. The level of upscaled PG was verified by comparing it to the ecosystem gross primary production (GPP) estimate calculated based on eddy covariance (EC) measurements. Although photosynthetic parameters differed within plant species and months, these differences were of less importance than expected for the variation in ecosystem level C sink. The most productive plant species at the ecosystem scale were not those with the highest maximum potential photosynthesis per unit of leaf area (Pmax), but those having the largest areal coverage. Sphagnum mosses had 35% smaller Pmax than vascular plants, but had higher photosynthesis at the ecosystem scale throughout the growing season. The contribution of the bog plant species to the ecosystem level PG differed over the growing season. The seasonal variation in ecosystem C sink was mainly controlled by phenology. Sedge PG had a sharp mid-summer peak, but the PG of evergreen shrubs and Sphagna remained rather stable over the growing season

  18. Could Poor Fens BE More Sensitive than Bogs to Elevated N Deposition in the Oil Sands Region of Northern Alberta?

    Science.gov (United States)

    Wieder, R. K.; Vile, M. A.; Scott, K. D.

    2015-12-01

    Bogs and fens cover 29% of the 140,000 km2 Oil Sands Administrative Area (OSAA) in northern Alberta, a region characterized by quite low background N deposition (1-2 kg/ha/yr). However, development of the oil sands resource has led to increasing emission of nitrogen oxides, which are then returned to regional ecosystems as elevated atmospheric N deposition. Given the nutrient deficient nature of bogs and poor fens, elevated N deposition from oil sands development could potentially affect peatland ecosystem structure and function. To evaluate the ecosystem-level effects of N deposition, since 2011, we have experimentally applied N to a bog and a poor fen near Mariana Lakes, Alberta, located far enough from the OSAA to be unaffected by oil sands emissions. Treatments include simulated rainfall equivalent to N deposition of 0, 5, 10, 15, 20, and 25 kg/ha/yr, plus control plots receiving no added water (3 replicate plots per site per N treatment). Concentrations of NH4+-N, NO3- N, and DON at the top of the peatland water table did not increase with increasing N deposition, averaging 0.61, 0.09, and 1.07 mg/L, respectively, in the bog, and 0.53, 0.10, and 0.81 mg/L, respectively, in the poor fen. Ericaceous shrub abundance increased with increasing N deposition in both the bog and the poor fen, although plot-scale greenness (hand-held spectral measurement of the Normalized Difference Red Edge (NDRE) index) increased with N deposition in the poor fen, but not in the bog. Segmented regression indicated that in the poor fen, at N deposition above 14-16 kg/ha/yr, total microbial, bacterial, and fungal biomass in the top 5 cm of peat increased with N deposition, with no effect at lower N deposition. No effect of N deposition on microbial, bacterial, or fungal biomass was observed at 5-10 cm in the poor fen, or at either 0-5 or 5-10 cm in the bog. In the poor fen, microbial, bacterial, and fungal biomass increased with NDRE, but the effect was not significant in the bog

  19. 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 depos

  20. 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 in

  1. Temperature-induced increase in methane release from peat bogs: a mesocosm experiment.

    Science.gov (United States)

    van Winden, Julia F; Reichart, Gert-Jan; McNamara, Niall P; Benthien, Albert; Damsté, Jaap S Sinninghe

    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 increasing water levels will enhance methane production, but also methane oxidation. To unravel the temperature effect on methane and carbon cycling, a set of mesocosm experiments were executed, where intact peat cores containing actively growing Sphagnum were incubated at 5, 10, 15, 20, and 25°C. After two months of incubation, methane flux measurements indicated that, at increasing temperatures, methanotrophs are not able to fully compensate for the increasing methane production by methanogens. Net methane fluxes showed a strong temperature-dependence, with higher methane fluxes at higher temperatures. After removal of Sphagnum, methane fluxes were higher, increasing with increasing temperature. This indicates that the methanotrophs associated with Sphagnum plants play an important role in limiting the net methane flux from peat. Methanotrophs appear to consume almost all methane transported through diffusion between 5 and 15°C. Still, even though methane consumption increased with increasing temperature, the higher fluxes from the methane producing microbes could not be balanced by methanotrophic activity. The efficiency of the Sphagnum-methanotroph consortium as a filter for methane escape thus decreases with increasing temperature. Whereas 98% of the produced methane is retained at 5°C, this drops to approximately 50% at 25°C. This implies that warming at the mid to high latitudes may be enhanced through increased methane release from peat bogs.

  2. Temperature-induced increase in methane release from peat bogs: a mesocosm experiment.

    Directory of Open Access Journals (Sweden)

    Julia F van Winden

    Full Text Available 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 increasing water levels will enhance methane production, but also methane oxidation. To unravel the temperature effect on methane and carbon cycling, a set of mesocosm experiments were executed, where intact peat cores containing actively growing Sphagnum were incubated at 5, 10, 15, 20, and 25°C. After two months of incubation, methane flux measurements indicated that, at increasing temperatures, methanotrophs are not able to fully compensate for the increasing methane production by methanogens. Net methane fluxes showed a strong temperature-dependence, with higher methane fluxes at higher temperatures. After removal of Sphagnum, methane fluxes were higher, increasing with increasing temperature. This indicates that the methanotrophs associated with Sphagnum plants play an important role in limiting the net methane flux from peat. Methanotrophs appear to consume almost all methane transported through diffusion between 5 and 15°C. Still, even though methane consumption increased with increasing temperature, the higher fluxes from the methane producing microbes could not be balanced by methanotrophic activity. The efficiency of the Sphagnum-methanotroph consortium as a filter for methane escape thus decreases with increasing temperature. Whereas 98% of the produced methane is retained at 5°C, this drops to approximately 50% at 25°C. This implies that warming at the mid to high latitudes may be enhanced through increased methane release from peat bogs.

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

    International Nuclear Information System (INIS)

    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

  4. 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.

  5. Atmospheric methane sources: Alaskan tundra bogs, an alpine fen, and a subarctic boreal marsh

    OpenAIRE

    Sebacher, Daniel I.; Harriss, Robert C.; Bartlett, Karen B.; Sebacher, Shirley M.; Grice, Shirley S.

    2011-01-01

    Methane (CH4) flux measurements from Alaskan tundra bogs, an alpine fen, and a subarctic boreal marsh were obtained at field sites ranging from Prudhoe Bay on the coast of the Arctic Ocean to the Alaskan Range south of Fairbanks during August 1984. In the tundra, average CH4 emission rates varied from 4.9 mg CH4 m-2 d-1 (moist tundra) to 119 mg CH4 m-2 d-1 (waterlogged tundra). Fluxes averaged 40 mg CH4 m-2 d-1 from wet tussock meadows in the Brooks Range and 289 mg CH4 m-2 d-1 from an alpine...

  6. Reconstructing historical atmospheric mercury deposition in Western Europe using : Misten peat bog cores, Belgium

    OpenAIRE

    Allan, Mohammed; Le Roux, Gaël; Jeroen E Sonke; Piotrowska, Natalia; Streel, Maurice; Fagel, Nathalie

    2013-01-01

    Four sediment cores were collected in 2008 from the Misten ombrotrophic peat bog in the Northern part of the Hautes Fagnes Plateau in Belgium. Total mercury (Hg) concentrations were analyzed to investigate the intra-site variability in atmospheric Hg deposition over the past 1500 years. Mercury concentrations in the four cores ranged from 16 to 1100 μg kg− 1, with the maxima between 840 and 1100 μg kg− 1. A chronological framework was established using radiometric 210Pb and 14C dating of two ...

  7. 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

  8. 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

  9. Elevated Nitrogen Deposition Enhances the Net CO2 Sink Strength in Alberta Bogs along a Post-fire Chronosequence

    Science.gov (United States)

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

    2014-12-01

    About 30% of the landscape of northern Alberta, Canada is occupied by peatlands, which persist at the low end range of both mean annual precipitation (moss, was not affected by N addition, suggesting that the overall response of NEE to N addition is the result of enhanced growth of ericaceous shrubs. These findings suggest that while elevated N deposition in the AOSR may enhance the strength of the overall CO2 sink of bogs in the short term, in the longer term, increased shrub growth has the potential to shade Sphagnum mosses, compromising the future bog CO2sink strength across the region.

  10. Multi-omics of Permafrost, Active Layer and Thermokarst Bog Soil Microbiomes

    Energy Technology Data Exchange (ETDEWEB)

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

    2015-03-04

    Over 20% of Earth’s terrestrial surface is underlain by permafrost with vast stores of carbon that, if thawed may represent the largest future transfer of C from the biosphere to the atmosphere 1. 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 2-4 and a rapid shift in functional gene composition during short-term thaw experiments 3. However, the fate of permafrost C depends on climatic, hydrologic, and microbial responses to thaw at decadal scales 5, 6. Here the combination of several molecular “omics” approaches enabled us to determine the phylogenetic composition of the microbial community, 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 revealed 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.

  11. Near-neutral carbon dioxide balance at a seminatural, temperate bog ecosystem

    Science.gov (United States)

    Hurkuck, Miriam; Brümmer, Christian; Kutsch, Werner L.

    2016-02-01

    The majority of peatlands in the temperate zone is subjected to drainage and agricultural land use and have been found to be anthropogenic emission hot spots for greenhouse gases. At the same time, many peatlands receive increased atmospheric nitrogen (N) deposition by intensive agricultural practices. Here we provide eddy covariance measurements determining net ecosystem carbon dioxide (CO2) exchange at a protected but moderately drained ombrotrophic bog in Northwestern Germany over three consecutive years. The region is dominated by intensive agricultural land use with total (wet and dry) atmospheric N deposition being about 25 kg N ha-1 yr-1. The investigated peat bog was a small net CO2 sink during all three years ranging from -9 to -73 g C m-2 yr-1. We found temperature- and light-dependent ecosystem respiration (Reco) and gross primary production, respectively, but only weak correlations to water table depths despite large interannual and seasonal variability. Significant short-term effects of atmospheric N deposition on CO2 flux components could not be observed, as the primary controlling factors for N deposition and C sequestration, i.e., fertilization of adjacent fields as well as temperature and light availability, respectively, exceeded potential interactions between the two.

  12. 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

  13. Nitrogen dynamics in peat bogs: Comparison of sites with contrasting pollution levels (Central Europe)

    Science.gov (United States)

    Novak, Martin; Bohdalkova, Leona; Stepanova, Marketa; Vile, Melanie A.; Wieder, Kelman R.

    2013-04-01

    Nitrogen belongs to chemical elements whose biogeochemical cycles are most heavily disturbed by human activities, and large regions worlwide experience elevated depositions of reactive N (NO3-, NH4+). Peatlands contain as much as 15 % of the world's soil N. It it is unclear whether fertilizing by anthopogenic N will lead to higher storage of C in wetlands. Elevated N input may lead to both higher net primary productivity, but will also augment microbial decomposition. Here we discuss two aspects of N cycling in Sphagnum-dominated bogs in the Czech Republic, an area characterized by a steep north-south pollution gradient and high annual N deposition (60 kg ha-1). These two aspects are N inventory in 210Pb-dated peat cores, and post-depositional mobility of N in peat. We compared the N inventory in two Czech bogs, differing in pollution, with cumulative atmospheric N input. We hypothesized that the total amount of N in the peat cores would be smaller than the cumulative N input (leaching of excess N from the bog, denitrification). The two bogs were VJ (industrial north) and CB (rural south). The investigated period was 1885-2002. The total amount of N was 4020 kg ha-1 at VJ and 1530 kg ha-1 at CB. Peat in the north contained 2.6 times more N than in the south. Historical rates of N deposition in the Czech Republic are well known (numerous papers by Kopacek). To estimate cumulative N inputs into the bogs, we also used the monthly N depositions between 1994 and 2002, measured in two nearby catchments. The estimated cumulative atmospheric N input was 1350 kg ha-1 at VJ, and 530 kg ha-1 at CB. In both cases, the amount of N found in peat was 3 times higher than the estimated atmospheric N input. Such high storage of N in peat is surprising. Post-depositional mobility of N may help to explain the discrepancies between atmospheric N inputs and N storage in peat. We found two-fold evidence for post-depositional mobility of N. Maximum N concentrations at VJ were observed in

  14. Carbon and Nitrogen Isotope Variation in Peat Bogs in the Midwestern US: Implications for Holocene Climate Reconstruction

    Science.gov (United States)

    Wong, D.; Paytan, A.; Jackson, S.

    2008-12-01

    A peat core, from near the center of Minden Bog in Michigan, representing about 3500 years of accumulation was previously analyzed for plant macrofossils, colorimetric humification, and testate amoebae to yield three independent climate proxies (Booth and Jackson, 2003). The plant macrofossil data show the site to be sensitive to bog water table fluctuations. The data suggest that this may be related to regional climatic changes. We analyzed the carbon and nitrogen isotopes, as well as the carbon-nitrogen ratios in the bulk peat samples to determine if fluctuations of these records correspond to climate events as seen in the plant microfossil and amoebae records. The degree to which peat-based carbon and nitrogen isotope records reflect changes in the relative distribution of vegetation and, in turn, reflect temperature changes in effective precipitation (precipitation minus evapotranspiration) will be assessed. Peat carbon and nitrogen isotope records will be compared with existing proxy climate records and with a temperature reconstruction based on testate amoebae in bogs. We expect that climate-related changes, in the relative abundance of vegetation remains accumulating in the peat bogs, will be recorded in the organic matter in forms of carbon and nitrogen isotopes.

  15. Influence of selected environmental factors on the abundance of aerobic anoxygenic phototrophs in peat-bog lakes.

    Science.gov (United States)

    Lew, Sylwia; Lew, Marcin; Koblížek, Michal

    2016-07-01

    Aerobic anoxygenic phototrophs (AAPs) are photoheterotrophic prokaryotes that are widespread in many limnic and marine environments. So far, little is known about their distribution in peat-bog lakes. Seventeen peat-bog lakes were sampled during three summer seasons 2009, 2011, and 2012, and the vertical distribution of AAPs was determined by infrared epifluorescence microscopy. The analysis demonstrated that in the surface layers of the studied lakes, AAP abundance ranged from 0.3 to 12.04 × 10(5) cells mL(-1), which represents water column with minimum numbers in the anoxic bottom waters. We have shown that the AAP abundance was significantly positively correlated with the water pH, and the highest proportion of photoheterotrophs was found in peat-bog lakes with a pH between 6.7 and 7.6. Our results demonstrated an influence of water acidity on the abundance of AAPs, which may reflect a fundamental difference in the microbial composition between acidic and pH neutral peat-bog lakes. PMID:27032635

  16. 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 recor

  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 wa

  18. The uptake of Ni2+ and Ag+ by bacterial strains isolated from a boreal nutrient-poor bog

    Directory of Open Access Journals (Sweden)

    Merja Lusa

    2016-05-01

    Full Text Available We studied the uptake of Ni2+ and Ag+ by bacterial strains of Paenibacillus, Pseudomonas, Burkholderia and Rhodococcus isolated from an acidic nutrient-poor boreal bog. The tests were run in two different growth media at two temperatures; +4 °C and +20 °C. All bacterial strains removed Ni2+ and Ag+ from the solution with highest efficiencies shown by one of the Pseudomonas sp. and one of the Paenibacillus sp. strains. Highest Ni2+ uptake was found in 1% Tryptone solution, whereas the highest removal of Ag+ was obtained using 1% Yeast extract. Temperature affected the uptake of Ni2+ and Ag+, but statistically significant difference was found only for Ni2+. Based on tests carried out for the bacteria in nutrient broths and for fresh samples taken from varying depth up to seven meters from the ombrotrophic bog, from which the bacteria were isolated, we estimated that in in situ conditions of the bog the uptake of Ni2+ by bacteria accounts for approximately 0.02% of the total sorption in the uppermost moss layer, 0.01% in the peat layer, 0.02% in the gyttja layer and 0.1% in the bottom clay layer of the bog. For Ag+ the corresponding values were 2.3% in the moss layer, 0.04% in the peat layer, 0.2% in the gyttja and 0.03% in the clay layer.

  19. 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.

  20. Peat bog records of dust deposition over the last 2000 years in the Dolomites (NE Italian Alps)

    Science.gov (United States)

    Poto, Luisa; Segnana, Michela; Gabrieli, Jacopo; Zaccone, Claudio; Barbante, Carlo

    2016-04-01

    The reconstruction of dust composition and fluxes is crucial to help to understand climate variability and climate changes. Dust fluctuations, linked to changes in dry and wet depositions, can indicate more humid or arid conditions, changes in temperature, vegetation cover and wind regimes. Peatlands are unique terrestrial archives that can capture changes in atmospheric deposition over time. Among them, ombrotrophic environments are hydrologically isolated from the surrounding landscapes receiving all the nutrients from precipitation and wind, with no influence from streams and groundwater. In recent decades biological and chemical proxies from peat bogs were extensively used to trace past climate changes, and rare earth elements (REE) in particular have been developed as inorganic geochemical proxies of mineral dust input in the atmosphere that plays an important role in the marine and terrestrial biogeochemical cycle as source for both major and trace elements. Dust deposition in the Italian Alps during the last 2000 years is estimated from the geochemical signature of two ombrotrophic peatlands. The first bog is located in Danta di Cadore (Belluno province, 1400 m a.s.l.), the second one in Coltrondo (Belluno province, 1800 m a.s.l.): they both allow us to have new insights into climate variability in the Eastern sector of the Italian Alps. The REE and the lithogenic elements concentration, as well as the lead isotopic composition were determined by CRC-ICP-QMS along the first meter of each core. For both the archives chronology is based upon independent 14C and 210Pb measurements. Changes in REE concentration through the bogs were related with those of lithogenic elements in order to test the immobility of the REE. Moreover peat humification degree was used to evaluate the hydroclimatic conditions of the bogs and Pb isotopic signature were used to trace dust deposited at Danta di Cadore and Coltrondo bogs and to discriminate natural from anthropogenic source

  1. Different patterns of genetic structure of relict and isolated populations of endangered peat-bog pine (Pinus uliginosa Neumann).

    Science.gov (United States)

    Wachowiak, W; Prus-Glowacki, W

    2009-01-01

    Recent changes in environmental conditions in populations of peat-bog pine (Pinus uliginosa Neumann) caused rapid decline or even extinction of the species in several stands in Central Europe. Conservation strategies for P. uliginosa require information about the evolutionary history and genetic structure of its populations. Using isozymes we assessed the genetic structure of P. uliginosa from four isolated stands in Poland and compared the results to genetic structures of other closely related pine species including eight populations of Pinus mugo, ten of Pinus sylvestris and one of Pinus uncinata. The level of genetic variability of P. uliginosa measured by the mean number of alleles per locus and average heterozygosity was similar to others related to P. uliginosa taxa from the reference group but it differs among populations. High genetic similarity was found between two populations of P. uliginosa from Low Silesian Pinewood. The populations were genetically distinct as compared to other populations including locus classicus of the species from the peat bog at Batorów Reserve. Very low genetic distance (DN = 0.002) and small genetic differentiation (GST = 0.003) were found between P. uliginosa and P. mugo in the sympatric populations of the species from Zieleniec peat bog suggesting the ongoing natural hybridisation and genetic contamination of peat-bog pine from this area. Some evidence for skew in allele frequency distribution potentially due to recent bottleneck was found in population from Low Silesian Pinewood. The analysed open pollinated progeny derived from two P. uliginosa stands from Low Silesian Pinewood showed the excess of homozygotes as compared to the maternal trees indicating high level of inbreeding (F = 0.105, F = 0.081). The results are discussed in the context of evolution of P. uliginosa populations, taxonomic relationships between the analysed species and conservation strategies for active protection of peat-bog pine. PMID:19875883

  2. 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.

  3. Simulated thaw development of a peat plateau-bog complex in a discontinuous permafrost region, Northwest Territories, Canada

    Science.gov (United States)

    Kurylyk, Barret; Hayashi, Masaki; Quinton, William; Voss, Clifford

    2015-04-01

    Air temperatures at high latitudes have increased at rates that exceed globally averaged trends, and this warming has produced rapid permafrost degradation in many areas. In discontinuous permafrost regions of the Taiga Plains of northwestern Canada, past climate warming has created a complex landscape mosaic of fully thawed bogs/fens and remnant peat plateaus underlain by thin permafrost. The thawing of peat plateaus can alter the landscape hydrologic connectivity by creating pathways to efficiently convey water from bogs to nearby rivers and lakes. Extensive monitoring of the thermal regime of a peat plateau-bog complex in the Scotty Creek watershed (61.3° N, 121.3° W), Northwest Territories, Canada has identified rapid permafrost degradation in the past decade. In addition, satellite images indicate major landscape evolution due to permafrost thaw since 1970, and these changes have resulted in increased discharge at the watershed outlet. These long term comprehensive data facilitate the numerical modeling of idealized permafrost environments based on observed data. The objective of this research project is to elucidate fundamental processes that contribute to multi-dimensional permafrost thaw and associated hydrological changes in discontinuous permafrost regions. The thaw evolution in this peat plateau-bog complex is simulated using SUTRA, a numerical groundwater flow and coupled heat transport model that has been modified to include dynamic freeze-thaw processes. To accommodate complex surface processes, measured climate data from 1900-2010 are used to drive a separate soil-vegetation-atmosphere energy transfer model. Near-surface temperatures produced by the vertical transfer model for the peat plateau and bog are applied as the upper thermal boundary conditions for the multi-dimensional subsurface heat transport simulations in SUTRA (1900-2010). The simulated thaw development of this peat plateau will be compared to satellite imagery to assess the ability

  4. 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

  5. Deciphering the environmental and landscape evolution of Sierra Nevada (S Iberia) from bog archives

    Science.gov (United States)

    Garcia Alix, Antonio; Toney, Jaime L.; Jiménez-Moreno, Gonzalo; Ramos-Román, Maria J.; Anderson, R. Scott; Jiménez-Espejo, Francisco; Delgado Huertas, Antonio; Ruano, Patricia

    2016-04-01

    Sierra Nevada is the southernmost mountain range in the Iberian Peninsula and one of the highest in Europe. Its geomorphology was the result of Pleistocene glaciations that carved out depressions, valleys and cirques at high elevations in the metamorphic basement. Depressions gave rise to lakes and wetlands during the Holocene. Geophysical and organic geochemical analyses of biomarkers (n-alkanes) and bulk sediment (C and N ratio and isotopes) from two high elevation bogs (locally called "Borreguiles"): Borreguiles de la Virgen (BdlV) and Borreguiles de la Caldera (BdlC), have allowed us to track the hydrological evolution of the area and its relationship to climatic fluctuations of the western Mediterranean during the Holocene. Most of the bogs of this area resulted from the natural evolution of former small lakes. The records are 56 cm and 169 cm long, respectively. Geophysical data suggest that we recovered the whole sedimentary record from BdlC; however, there are some post-glacial sediments remaining below the BdlV core that we could not recover due to hard-ground conditions. During the early and middle Holocene, aquatic conditions predominated in BdlV compared to the most recent part of the record (low C/N values and high proportion of aquatic plants (Paq) deduced from the n-alkanes) suggesting a lake environment whose water level gradually decreased until ˜5.5 cal ky BP. This aridity trend is also observed in nearby records such as at Laguna de Río Seco (LdRS), a result of the African Humid Period demise. Carbon and nitrogen isotopes were higher during this interval, which might suggest more algae activity, in agreement with the highest concentrations of the algae Pediastrum in the area. There is an important development of terrestrial plants, a real bog stage (C/N higher than 20, high TOC, lower Paq) in both records from ˜5.5 to 3.5-3.0 cal ky BP. Those hydrological changes in the landscape might be related to a possible change in the source of

  6. Concentration changes of heavy metals in peat bog from Puscizna Rekowianska (southern Poland)

    International Nuclear Information System (INIS)

    A peat core of 40 cm length was taken from a peat bog in southern Poland and cut in 2 cm sections. The peat core was dated using the natural radionuclide 210Pb with a half life of 22,3 years. Concentrations of eighteen elements have been determined in all peat sections by means of energy dispersive X-ray fluorescence analysis (EDXRF). Since the efficiency in determining light, medium and heavy elements by EDXRF depends on some physical parameters, three respective methods for the X-ray analysis were applied. The concentration depth profiles for the determined elements and ash content profile were constructed. The results show strongly time dependent variations in the concentrations of the different elements. An interpretation is given and correlation between possible influence factors are discussed. High concentrations of Pb and Zn indicate their anthropogenic origin. (author)

  7. The Wonderful World of Wetlands (WWW): Bogs, fens, marshes and swamps and their global environmental significance

    Science.gov (United States)

    Shotyk, W.

    2012-04-01

    Bogs, fens, marshes, and swamps are waterlogged ecosystems where organic soils form and peat accumulates. These are remarkably diverse ecosystems and represent an important component of the biodiversity found on Earth. Their geochemical function is dominated by their predominately anoxic condition which has some important consequences. Best known as reservoirs and reactors for a significant part of our surface freshwater resources, and impacting their chemical composition in remarkable ways, they also have a significant influence on the atmosphere, removing CO2 and adding CH4. The contemporary view during the past centuries was that these were wastelands in need of improving by drainage. Today, however, in some circles at least, the remaining wetlands are valued ecosystems, and the soils they contain archives of climate change, human history and atmospheric pollution.

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

    Science.gov (United States)

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

    2015-05-01

    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 (Kd) values of iodide decreased as a function of sampling depth. The highest Kd 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 Kd 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 I2/HIO before incorporation into the organic matter. Furthermore, the Kd 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. PMID:25752706

  9. Ecohydrology by thinking outside the bog: Shifting paradigms in an era of shifting peatland ecosystems

    Science.gov (United States)

    Waddington, James; Moore, Paul

    2016-04-01

    Large shifts in vegetation distributions are occurring worldwide and at unprecedented rates. The most extreme of these regime shifts are expected to occur at ecosystem boundaries of both semi-arid and semi-humid landscapes. Despite extensive hydrological research on the interactions between water and semi-arid ecosystems, research in peatlands on the wet end of ecosystem continuum has been "bogged down" (pun fully intended) by the traditional conceptual models (paradigms?) of peatland hydrology and ecology. The consequences of this "thinking" are large given that northern peatlands provide important global and regional ecosystem services (carbon storage, water storage, and biodiversity). This is especially true because peatlands face increases in the severity, areal extent, and frequency of climate-mediated (e.g., wildfire, drought) and land-use change (e.g., drainage, flooding, and mining) disturbances placing the future security of these critical ecosystem services in doubt. We use the word doubt because while numerical modelling studies predict peatland regime shifts and the demise of global peat stocks, there is growing evidence that peatlands are self-regulating ecosystems dominated by negative ecohydrological feedbacks that stabilize the aforementioned ecosystem services through high ecosystem resilience to disturbance. This raises several important hydrological questions? "Is there field evidence of peatland regime shifts? If so, what are the potential impacts of these shifts on water resources and watershed management? If not, are researchers actually looking in the right places (or times)? In this presentation we explore the need for a "thinking outside the bog" in order to understand the ecohydrological consequences of transformative landscape change caused by peatland regime shifts. With reference to over two decades of field research, recent advances with our Peatland Hydrological Impacts model and recent research examining primary peat formation, we

  10. Using stable isotopes of water to re-evaluate the recharge/discharge functions of North American bogs and fens

    Science.gov (United States)

    Levy, Zeno; Siegel, Donald; Glaser, Paul; Dasgupta, Soumitri

    2014-05-01

    In North American mires hydrologists commonly find raised bog crests and low-lying fen water tracks to be focal points for groundwater recharge and discharge, respectively. To further test these observations we synoptically surveyed vertical profiles of peat pore water δ18O/δ2H and major mineral solutes from a range of bog and fen landforms across the Glacial Lake Agassiz Peatlands (GLAP) of northern Minnesota. We also sampled a detailed transect through a 150 km2 bog-fen complex in the Red Lake II peatland watershed of the GLAP. The molar ratios of Ca/Mg in the pore water beneath the Red Lake II bog crest are depleted in Mg with respect to the atmospheric average of 3.6, indicative of preferential flushing of Mg from the peat by meteoric recharge. Higher solute concentrations in the middle of the peat profile at an adjacent fen show focused groundwater discharge with Ca/Mg ratios of ~1.4, similar to that of water from local wells tapping underlying glacial till. However, contrary to expectations, we find evidence that modern recharge has penetrated throughout the peat column beneath both bog and fen landforms throughout the GLAP. Landform surface features control the isotopic recharge value. These landform-specific isotope signatures propagate through vertical pore water profiles. Pore waters deeper than 0.5 m partition into discrete ranges of δ18O according to three a priori landform classifications: 1) -11.9 ± 0.4 o for bog crests, 2) -10.6 ± 0.1 o for Sphagnum lawns, and 3) -8.8 ± 1.0 o for fen water tracks. The fen water tracks have standing water at their surface that is seasonally enriched by isotope fractionating evaporation and therefore fingerprints recharge to depths ≥3 m. Incongruities between isotope and solute mixing trends may be related to the dual porosity nature of peat and matrix diffusion, which could supply solutes to active pore spaces following flushing by meteoric recharge. This buffering of base solutes in the deep peat may

  11. 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.

  12. THE CHEMICAL COMPOSITION OF TYPICAL PEAT-FORMING PLANTS LIPIDS OF WEST SIBERIA FOREST ZONE OLIGOTROPHIC BOGS

    Directory of Open Access Journals (Sweden)

    Ольга Викторовна Серебренникова

    2014-09-01

    Full Text Available The paper describes the molecular composition and distribution of hydrocarbons and oxygen-containing compounds in the main bog peat-forming plants – scheuchzeria, sedge, cotton grass and sphagnum moss. It is shown that all plants contain n-alkanes, arenes, sesquiterpenes, fatty acids, esters, aldehydes, alcohols and ketones. The most representative group of hydrocarbons (HC in all bog plants are n-alkanes. Arenas are presented by bi-, tri- and tetracyclic structures. Ketones include acyclic compounds with normal and isoprenoid structure and alicyclic compounds with two, four and five cycles. Alcohols are presented by aliphatic and monoaromatic structures, aldehydes, fatty acids and esters – by compounds with acyclic structure. Tetra- and pentacyclic oxygen-containing substances includes steroid and triterpenoid alcohols and ketones.

  13. Occurrence of organochlorine compounds in a forest bog at Stubbetorp, Kolmården : -Indication for a natural formation?

    OpenAIRE

    Hoppe, Sabina; Thomsen, Frida

    2005-01-01

    Volatile organochlorine compounds emitted from natural sources can participate in environmentally relevant processes affecting life on Earth, such as stratospheric ozone destruction and warming of the troposphere. The aim of this study was to investigate if forest bogs contribute to the environmental input of naturally produced volatile organochlorine compounds. The concentrations of four different volatile organochlorine compounds were determined in ambient air, rainwater, surface water, and...

  14. Isoenzymatic differentiation in putative hybrid swarm population (Pinus mugo Turra x P. sylvestris L.) from "Torfowisko Zieleniec" peat-bog

    OpenAIRE

    Anna Siedlewska

    2014-01-01

    Isoenzyme variability of eight groups of individuals from different parts of putative hybrid swarm population (P. mugo Turra x P. sylvestris L.) from "Torfowisko Zieleniec" peat-bog complex was studied at ten enzymatic loci. Differences in allelic frequencies distribution among particular samples of the Zieleniec population were statistically significant at 9 loci, as shown by G2- statistics. Chi-square test indicated that in each of studied subpopulations frequencies of alleles at some loci ...

  15. Overriding control of methane flux temporal variability by water table dynamics in a Southern Hemisphere, raised bog

    Science.gov (United States)

    Goodrich, J. P.; Campbell, D. I.; Roulet, N. T.; Clearwater, M. J.; Schipper, L. A.

    2015-05-01

    There are still large uncertainties in peatland methane flux dynamics and insufficient understanding of how biogeochemical processes scale to ecosystems. New Zealand bogs differ from Northern Hemisphere ombrotrophic systems in climatic setting, hydrology, and dominant vegetation, offering an opportunity to evaluate our knowledge of peatland methane biogeochemistry gained primarily from northern bogs and fens. We report eddy covariance methane fluxes from a raised bog in New Zealand over 2.5 years. Annual total methane flux in 2012 was 29.1 g CH4 m-2 yr-1, whereas during a year with a severe drought (2013) it was 20.6 g CH4 m-2 yr-1, both high compared to Northern Hemisphere bogs and fens. Drier conditions led to a decrease in fluxes from ~100 mg CH4 m-2 d-1 to ~20 mg CH4 m-2 d-1, and subsequent slow recovery of flux after postdrought water table rise. Water table depth regulated the temperature sensitivity of methane fluxes, and this sensitivity was greatest when the water table was within 100 mm of the surface, corresponding to the shallow rooting zone of the dominant vegetation. A correlation between daytime CO2 uptake and methane fluxes emerged during times with shallow water tables, suggesting that controls on methane production were critical in determining fluxes, more so than oxidation. Water table recession through this shallow zone led to increasing methane fluxes, whereas changes in temperature during these periods were not correlated. Models of methane fluxes should consider drought-induced lags in seasonal flux recovery that depend on drought characteristics and location of the critical zone for methane production.

  16. Parameter Calculation Technique for the Waste Treatment Facilities Using Naturally-Aerated Blocks in the Bog Ecosystems

    International Nuclear Information System (INIS)

    Technique for the domestic wastewater treatment in the small residential areas and oil and gas facilities of the natural and man-made systems including a settling tank for mechanical treatment and a biological pond with peat substrate and bog vegetation for biological treatment has been substantiated. Technique for parameters calculation of the similar natural and man-made systems has been developed. It was proven that effective treatment of wastewater can be performed in Siberia all year round

  17. Parameter Calculation Technique for the Waste Treatment Facilities Using Naturally-Aerated Blocks in the Bog Ecosystems

    Science.gov (United States)

    Akhmed-Ogly, K. V.; Savichev, O. G.; Tokarenko, O. G.; Pasechnik, E. Yu; Reshetko, M. V.; Nalivajko, N. G.; Vlasova, M. V.

    2014-08-01

    Technique for the domestic wastewater treatment in the small residential areas and oil and gas facilities of the natural and man-made systems including a settling tank for mechanical treatment and a biological pond with peat substrate and bog vegetation for biological treatment has been substantiated. Technique for parameters calculation of the similar natural and man-made systems has been developed. It was proven that effective treatment of wastewater can be performed in Siberia all year round.

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

    OpenAIRE

    Beyer, C.; Höper, H.

    2015-01-01

    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 pe...

  19. 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

  20. Non-Pollen Palynomorphs from Mid-Holocene Peat of the Raised Bog Borsteler Moor (Lower Saxony, Germany

    Directory of Open Access Journals (Sweden)

    Shumilovskikh Lyudmila S.

    2015-06-01

    Full Text Available In order to reconstruct regional vegetation changes and local conditions during the fen-bog transition in the Borsteler Moor (northwestern Germany, a sediment core covering the period be tween 7.1 and 4.5 cal kyrs BP was palynologically investigated. The pollen diagram demonstrates the dominance of oak forests and a gradual replacement of trees by raised bog vegetation with the wetter conditions in the Late Atlantic. At ~ 6 cal kyrs BP, the non-pollen palynomorphs (NPP demonstrate the succession from mesotrophic conditions, clearly indicated by a number of fun gal spore types, to oligotrophic conditions, indicated by Sphagnum spores, Bryophytomyces sphagni, and testate amoebae Amphitrema, Assulina and Arcella, etc. Four relatively dry phases during the transition from fen to bog are clearly indicated by the dominance of Calluna and associated fungi as well as by the in crease of microcharcoal. Several new NPP types are described and known NPP types are identified. All NPP are discussed in the context of their palaeoecological indicator values.

  1. A stacked record of late-Holocene moisture variability from three raised bogs in Maine

    Science.gov (United States)

    Clifford, M. J.; Booth, R. K.

    2011-12-01

    During the past century, drought has caused substantial social, economic, and ecological changes in North America. Semi-arid regions of the western United States have been particularly vulnerable to drought and drought impacts. However, drought has been less frequent and severe in humid regions of North America during the past century, leading to the perception that these regions are not particularly vulnerable to hydroclimatic change. Although the tree-ring record provides a detailed perspective on drought frequency and duration for the past millennium in the western US, much less is known about the long-term history of water balance in humid regions like the Northeast. To better understand the long-term history of moisture variability in this region, we developed records of past hydroclimate variability spanning the past 3000 years from three raised bogs in Maine. We used testate amoeba-inferred water table depths and measurements of the degree of peat decomposition to reconstruct the paleohydrology at each site. Proxy hydroclimate records from these bogs were combined (stacked), creating a single, regional record of hydroclimate variability. Our results reveal that droughts longer or more severe than any recorded during the 20th century have been common in the region, with particularly prominent multidecadal-to-centennial scale droughts centered on ~1800 yr BP, ~1650 yr BP, ~850 yr BP, and ~550 yr BP. Hydroclimate variability was greatest during the Medieval Climate Anomaly, a time period of relative warmth in much of the Northern Hemisphere. Droughts in Maine during the past century have been associated with northerly wind anomalies and anomalously cool sea surface temperatures in the adjacent northwestern North Atlantic, patterns that are likely associated with broader circulation features such as those associated with the North Atlantic Oscillation. Droughts of the past 3000 years may have been characterized by similar responses to the coupled ocean

  2. Holocene methane flux reconstruction from peat macrofossils at Siikaneva bog and fen, Finland

    Science.gov (United States)

    Mathijssen, Paul; Korrensalo, Aino; Tuittila, Eeva-Stiina; Väliranta, Minna; Mellais, Annina

    2015-04-01

    Previous studies have shown that a correlation exists between methane flux and peatland plant species abundance. Furthermore, it has been demonstrated that the composition of plant species or functional groups of species can be used as indicator for methane fluxes in peatlands, using weighted averaging. This method has the potential to be very useful in palaeoecological studies of peatlands as well. This method offers the possibility to reconstruct past methane flux based on vegetation remains still present in the peat archive and together with reconstructions of carbon accumulation can give a more complete picture of peatlands' carbon dynamics during the Holocene. Furthermore, effects of changes in hydrology or temperature on methane fluxes can be studied over much longer time scales, compared to what experimental setups allow for. For four peat cores from Siikaneva peatland in southern Finland, we reconstructed the methane flux during the Holocene. Two cores represent a part of the peatland that has currently a fen type vegetation. The other two cores were taken from a part of the peatland that has transformed into a bog, around 3.5 - 5.5 cal. year before present. The development of methane flux during the fen to bog transition is especially of interest. We used vegetation data and methane flux data from chamber measurement from all microtopographies found on Siikaneva and from a few similar peatlands in southern and central Finland as a training set. The plant species were classified into functional groups. Firstly, because it has been shown that usage of functional groups leads to better predictions of methane flux when compared to e.g. species or dominant species. Secondly, the information from the peat cores used as input for the reconstruction is based on progressively decomposed plant remains in subsequent peat layers, for which identification to species level is not always possible (most notably for sedges). We compare the predictive performance of two

  3. Halogens in porewater of peat bogs – the role of peat decomposition and dissolved organic matter

    Directory of Open Access Journals (Sweden)

    H. Biester

    2005-09-01

    Full Text Available Peatlands are one of the largest active terrestrial reservoirs of halogens. Formation of organo-halogens is a key process for the retention of halogens by organic matter and halogen enrichment in peat is strongly influenced by climatically controlled humification processes. However, little is known about release and transport of halogens in peat bogs. In this study we investigated the release of halogens from peat in three peat bogs located in the Magellanic Moorlands, southern Chile. Peat porewaters were collected using a sipping technique, which allows in situ sampling down to a depth of more than 6 m. Halogens and halogen species in porewater were determined by ion-chromatography (IC (chlorine and IC-ICP-MS (bromine and iodine. Results show that halogen concentrations in porewater are 15–30 times higher than in rainwater suggesting that their release from peat during diagenesis is the major source of halogens in porewater. Mean concentrations of chlorine, bromine and iodine in porewater were 7–15 mg l−1, 56–123μg l−1, and 10–20μg l−1, which correspond to mean proportions of 10–15%, 1–2.3% and 0.5–2.2% of total concentrations in peat, respectively. Organo-bromine and organoiodine were predominant in porewaters, whereas the release of organo-chlorine compounds from peat appears to be of minor importance. Results show that the 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. Here, proportions of released iodine and bromine follow proportions of released dissolved organic matter (DOM indicating that the release of halogenated DOM is the predominant process of iodine and bromine release from peat.

  4. Reconstructing historical atmospheric mercury deposition in Western Europe using: Misten peat bog cores, Belgium

    Energy Technology Data Exchange (ETDEWEB)

    Allan, Mohammed, E-mail: mallan@doct.ulg.ac.be [Argiles, Geochimie et Environnement sedimentaires, Departement de Geologie, Universite de Liege, Allee du 6 Aout B18 Sart Tilman B4000-Liege (Belgium); Le Roux, Gael [Universite de Toulouse, INP, UPS, EcoLab (Laboratoire Ecologie Fonctionnelle et Environnement), ENSAT, Avenue de l' Agrobiopole, 31326 Castanet Tolosan (France); CNRS, EcoLab, 31326 Castanet Tolosan (France); Sonke, Jeroen E. [Geosciences Environnement Toulouse, CNRS/IRD/Universite de Toulouse 3, 14 avenue Edouard Belin, 31400 Toulouse (France); Piotrowska, Natalia [Department of Radioisotopes, GADAM Centre of Excellence, Institute of Physics, Silesian University of Technology, Gliwice (Poland); Streel, Maurice [PPM, Departement de Geologie, Universite de Liege, Allee du 6 Aout B18 Sart Tilman B4000-Liege (Belgium); Fagel, Nathalie [Argiles, Geochimie et Environnement sedimentaires, Departement de Geologie, Universite de Liege, Allee du 6 Aout B18 Sart Tilman B4000-Liege (Belgium)

    2013-01-01

    Four sediment cores were collected in 2008 from the Misten ombrotrophic peat bog in the Northern part of the Hautes Fagnes Plateau in Belgium. Total mercury (Hg) concentrations were analyzed to investigate the intra-site variability in atmospheric Hg deposition over the past 1500 years. Mercury concentrations in the four cores ranged from 16 to 1100 {mu}g kg{sup -1}, with the maxima between 840 and 1100 {mu}g kg{sup -1}. A chronological framework was established using radiometric {sup 210}Pb and {sup 14}C dating of two cores (M1 and M4). Pollen horizons from these two cores were correlated with data from two additional cores, providing a consistent dating framework between all the sites. There was good agreement between atmospheric Hg accumulation rates in the four cores over time based on precise age dating and pollen chronosequences. The average Hg accumulation rate before the influence of human activities (from 500 to 1300 AD) was 1.8 {+-} 1 {mu}g m{sup -2} y{sup -1} (2SD). Maximum Hg accumulation rates ranged from 90 to 200 {mu}g m{sup -2} y{sup -1} between 1930 and 1980 AD. During the European-North American Industrial Revolution, the mean Hg accumulation rate exceeded the pre-Industrial values by a factor of 63. Based on comparisons with historical records of anthropogenic activities in Europe and Belgium, the predominant regional anthropogenic sources of Hg during and after the Industrial Revolution were coal burning and smelter Hg emissions. Mercury accumulation rates and chronologies in the Misten cores were consistent with those reported for other European peat records. -- Highlights: Black-Right-Pointing-Pointer Study of Hg concentration in four cores from Belgian peat bog. Black-Right-Pointing-Pointer Reconstruction of Hg deposition over last 1500 years. Black-Right-Pointing-Pointer Maximum Hg accumulation rates ranging from 90 to 200 {mu}g m{sup -2} y{sup -1} are recorded between 1930 and 1980 AD. Black-Right-Pointing-Pointer The average Hg

  5. Fate and Transport of Road Salt During Snowmelt Through a Calcareous Fen: Kampoosa Bog, Stockbridge, Massachusetts

    Science.gov (United States)

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

    2007-12-01

    Kampoosa Bog is the largest and most ecologically diverse calcareous lake-basin fen in Massachusetts. Situated within a 4.7 km2 drainage basin, the open fen (approx. 20 acres) consists of a floating mat of sedges (incl. Carex aquatilis and Cladium mariscoides) that overlie peat and lake clay deposits. Mineral weathering of marble bedrock within the drainage basin supplies highly alkaline ground and surface waters to the fen basin. The natural chemistry has been greatly altered by road salt runoff from the Massaschusetts Turnpike, and in question is whether disturbance from the Turnpike and a gas pipline has facilitated aggressive growth by the invasive species Phragmites australis. Considered to be one of the most significant rare species habitats in the state, Massachusetts has designated Kampoosa Bog an Area of Critical Environmental Concern, and a committee representing several local, regional, and state agencies, organizations, and citizens manages the wetland. The purpose of this study is to characterize the hydrologic and chemical response of the wetland during snowmelt events to understand the fate and movement of road salt (NaCl). Concentrations of Na and Cl in the fen groundwater are greatest close to the Turnpike. Concentrations decrease with distance downstream but are still greatly elevated relative to sites upstream of the Turnpike. During snowmelt events, the fen's outlet shows a sharp rise in Na and Cl concentrations at the onset of melting that is soon diluted by the added meltwater. The Na and Cl flux, however, is greatest at peak discharge, suggesting that high-flow events are significant periods of export of dissolved salts from the fen. Pure dissolution of rock salt produces an equal molar ratio between Na and Cl, and sodium and chloride imbalances in stream and ground waters suggest that ~20% of the Na is stored on cation exchange sites within the peat. The largest imbalances between Na and Cl occur deeper within the peat, where the peat is

  6. Reconstructing historical atmospheric mercury deposition in Western Europe using: Misten peat bog cores, Belgium

    International Nuclear Information System (INIS)

    Four sediment cores were collected in 2008 from the Misten ombrotrophic peat bog in the Northern part of the Hautes Fagnes Plateau in Belgium. Total mercury (Hg) concentrations were analyzed to investigate the intra-site variability in atmospheric Hg deposition over the past 1500 years. Mercury concentrations in the four cores ranged from 16 to 1100 μg kg−1, with the maxima between 840 and 1100 μg kg−1. A chronological framework was established using radiometric 210Pb and 14C dating of two cores (M1 and M4). Pollen horizons from these two cores were correlated with data from two additional cores, providing a consistent dating framework between all the sites. There was good agreement between atmospheric Hg accumulation rates in the four cores over time based on precise age dating and pollen chronosequences. The average Hg accumulation rate before the influence of human activities (from 500 to 1300 AD) was 1.8 ± 1 μg m−2 y−1 (2SD). Maximum Hg accumulation rates ranged from 90 to 200 μg m−2 y−1 between 1930 and 1980 AD. During the European–North American Industrial Revolution, the mean Hg accumulation rate exceeded the pre-Industrial values by a factor of 63. Based on comparisons with historical records of anthropogenic activities in Europe and Belgium, the predominant regional anthropogenic sources of Hg during and after the Industrial Revolution were coal burning and smelter Hg emissions. Mercury accumulation rates and chronologies in the Misten cores were consistent with those reported for other European peat records. -- Highlights: ► Study of Hg concentration in four cores from Belgian peat bog. ► Reconstruction of Hg deposition over last 1500 years. ► Maximum Hg accumulation rates ranging from 90 to 200 μg m−2 y−1 are recorded between 1930 and 1980 AD. ► The average Hg accumulation rate before the influence of human activities (e.g. 1300 AD) was 1.8 ± 1 μg m−2 y−1. ► The predominant anthropogenic Hg sources were coal

  7. Palynology of cushion bogs of the Cordillera Pelada, Province of Valdivia, Chile

    Science.gov (United States)

    Heusser, Calvin J.

    1982-01-01

    Fossil pollen identified in the earliest sediments of three cushion bogs in the Cordillera Pelada (40°10'S, 73°30'W) dated 10,425 14C yr B.P. includes the subantarctic species Dacrydium fonckii, Tetroncium magellanicum, Astelia pumila, Gaimardia australis, Donatia fascicularis, and Drosera uniflora. All grow today in the Cordillera Pelada and range poleward to the southernmost Province of Magallanes; one species, Drapetes muscosa, included with the pollen of these plants in the earliest record, is no longer a constituent of the flora but is limited only to subantarctic Chile. Available evidence indicates that plants survived the last glaciation north of the glacial border with the course of postglacial migration southward following the wastage of the glacier complex. Holocene climatic and vegetational changes in the Cordillera Pelada are interpreted in the context of regional reconstructions which show maximum warmth about 9000 yr ago with a pronounced dry period lasting from 9000 to 6500 yr B.P. Maximum precipitation was later reached around 4000 yr ago but has decreased overall since then. The regional decline of the endemic gymnosperm Fitzroya cupressoides, which today is extensively destroyed in the Cordillera Pelada, follows this decrease in precipitation. These climatic data suggest a net south ward shift in the zone of westerly winds that bring rainfall to the region over the past 4000 yr.

  8. Atmospheric supply of trace elements studied by peat samples from ombrotrophic bogs.

    Science.gov (United States)

    Steinnes, E; Hvatum, O Ø; Bølviken, B; Varskog, P

    2005-01-01

    Concentrations of Fe and 12 trace elements in peat from ombrotrophic bogs were used to estimate the atmospheric deposition of these elements on a temporal and spatial scale. Peat samples were collected at 21 different sites in Norway encompassing large geographical differences in marine influence and air pollution. The study demonstrates that surface peat is an excellent medium to study geographical differences in heavy metal deposition, provided that effects of the surface plant cover are properly considered. Long-range atmospheric transport of pollutants is the main source for As, Cd, Pb, Sb, and Zn, and to a lesser extent for Cu and Se. Biogenic emissions from the ocean appear to be the main source of Se to the peat. The metals Co, Cr, Fe, and Ni are mainly associated with wind-blown local soil dust. Surface enrichment of Mn, and in part Zn, is mainly caused by nutrient circulation between the surface peat and vascular plants growing on it. Deposition of marine salts appears to be the main reason for lower Mn concentrations in the peat near the coast.

  9. Vegetation drives belowground biogeochemical gradients and C accumulation in an ombrotrophic bog

    Science.gov (United States)

    Knorr, Klaus-Holger; Galka, Mariusz; Borken, Werner

    2016-04-01

    Peat decomposition and C accumulation is determined by hydrology and climate and by concomitant changes in vegetation and changes in the quality of carbon inputs. Especially changes from moss dominated to vascular plant dominated vegetation affect belowground biogeochemistry and decomposition, as Sphagnum mosses provide refractory, nutrient poor litter, while vascular plants produce more labile litter and may have aerenchymatic rooting systems. In-site variability in moisture and vegetation, e.g. hummock-hollow structures, lawns, and medium scale surface topography, could thus cause large differences in decomposition and C accumulation within a site. In order to understand within-site variability and to see how C accumulation, common decomposition indices, and major biogeochemical parameters in the pore waters are affected by site specific conditions and vegetation, we investigated a moisture-vegetation gradient along a 800 m transect in an oceanic, ombrotrophic bog in Southern Patagonia. Along the transect, conditions changed from wet, Sphagnum dominated (S. magellanicum), to intermediate drier and wetter with Sphagnum/shrubs mixtures, sedges and rushes to more wind exposed, dominated by cushion plants (mainly Astelia pumila). We hypothesized that under arenchymatic vascular plants, decomposition is enhanced and C accumulation is decreased. Vegetation development was elucidated by plant macrofossils and carbon accumulation was attributed to the respective vegetation. The transect demonstrated a high variability of depth records within the bog. At the two most contrasting sites, the uppermost 1 meter persistently dominated by either Sphagnum magellanicum or Astelia pumila had accumulated over 2400 or 4200 years, respectively. Accordingly, the peat under cushion plants was much more decomposed, with C/N ratios of 20-50 compared to C/N ratios of 40-80 under Sphagnum patches. Mixed sites in between had C/N ratios of 30-90, depending on plant community, and

  10. Recent atmospheric dust deposition in an ombrotrophic peat bog in Great Hinggan Mountain, Northeast China.

    Science.gov (United States)

    Bao, Kunshan; Xing, Wei; Yu, Xiaofei; Zhao, Hongmei; McLaughlin, Neil; Lu, Xianguo; Wang, Guoping

    2012-08-01

    Recent deposition of atmospheric soil dust (ASD) was studied using (210)Pb-dated Sphagnum-derived peat sequences from Great Hinggan Mountain in northeast China. Physicochemical indices of peat including dry bulk density, water content, ash content, total organic carbon and mass magnetic susceptibility were measured. Acid-insoluble concentration of lithogenic metals (Al, Ca, Fe, Mn, V and Ti) were measured using ICP-AES. The basic physicochemical properties were used to assess the peat trophic status and indicated that the sections above 45-60 cm are rain-fed peat. A continuous record of ASD fluxes over the past 150 years was reconstructed based on the geochemical data obtained from the ombrotrophic zone, and the average input rate of ASD is 13.4-68.1 g m(-2) year(-1). The source of soil dust deposited in peat was dominated by the long-range transport of mineral aerosol from the drylands in north China and Mongolia. The temporal variation of ASD fluxes in the last 60 years coincides well with the meteorological records of dust storm frequency during 1954-2002 in north China. This suggests that the reconstructed sequence of atmospheric dust deposition is reliable and we can look back in time at the dust evolution before 1949. Dust storm events were observed occasionally in the late Qing dynasty, and their frequency and intensity were smaller than dust weather occurring in recent times. Four peaks of ASD fluxes were distinguished and correlated with the historical events at that time. This study presents the first atmospheric soil dust data in peat records in northeast China, and complements a global database of peat bog archives of atmospheric deposition. The results reflect the patterns of local environmental change over the past century in north China and will be helpful in formulating policies to achieve sustainable and healthy development.

  11. 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.

  12. Recent atmospheric dust deposition in an ombrotrophic peat bog in Great Hinggan Mountain, Northeast China.

    Science.gov (United States)

    Bao, Kunshan; Xing, Wei; Yu, Xiaofei; Zhao, Hongmei; McLaughlin, Neil; Lu, Xianguo; Wang, Guoping

    2012-08-01

    Recent deposition of atmospheric soil dust (ASD) was studied using (210)Pb-dated Sphagnum-derived peat sequences from Great Hinggan Mountain in northeast China. Physicochemical indices of peat including dry bulk density, water content, ash content, total organic carbon and mass magnetic susceptibility were measured. Acid-insoluble concentration of lithogenic metals (Al, Ca, Fe, Mn, V and Ti) were measured using ICP-AES. The basic physicochemical properties were used to assess the peat trophic status and indicated that the sections above 45-60 cm are rain-fed peat. A continuous record of ASD fluxes over the past 150 years was reconstructed based on the geochemical data obtained from the ombrotrophic zone, and the average input rate of ASD is 13.4-68.1 g m(-2) year(-1). The source of soil dust deposited in peat was dominated by the long-range transport of mineral aerosol from the drylands in north China and Mongolia. The temporal variation of ASD fluxes in the last 60 years coincides well with the meteorological records of dust storm frequency during 1954-2002 in north China. This suggests that the reconstructed sequence of atmospheric dust deposition is reliable and we can look back in time at the dust evolution before 1949. Dust storm events were observed occasionally in the late Qing dynasty, and their frequency and intensity were smaller than dust weather occurring in recent times. Four peaks of ASD fluxes were distinguished and correlated with the historical events at that time. This study presents the first atmospheric soil dust data in peat records in northeast China, and complements a global database of peat bog archives of atmospheric deposition. The results reflect the patterns of local environmental change over the past century in north China and will be helpful in formulating policies to achieve sustainable and healthy development. PMID:22664536

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

    International Nuclear Information System (INIS)

    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

  14. Ombrotrophic peat bogs are not suited as natural archives to investigate the historical atmospheric deposition of perfluoroalkyl substances.

    Science.gov (United States)

    Dreyer, Annekatrin; Thuens, Sabine; Kirchgeorg, Torben; Radke, Michael

    2012-07-17

    As ombrotrophic peat bogs receive only atmospheric input of contaminants, they have been identified as suitable natural archives for investigating historical depositions of airborne pollutants. To elucidate their suitability for determining the historical atmospheric contamination with perfluoroalkyl substances (PFAS), two peat cores were sampled at Mer Bleue, a bog located close to Ottawa, Canada. Peat cores were segmented, dried, and analyzed in duplicate for 25 PFASs (5 perfluororalkyl sulfonates (PFSAs), 13 perfluoroalkyl carboxylates (PFCAs), 7 perfluororalkyl sulfonamido substances). Peat samples were extracted by ultrasonication, cleaned up using a QuEChERS method, and PFASs were measured by HPLC-MS/MS. Twelve PFCAs and PFSAs were detected regularly in peat samples with perfluorooctane sulfonate (85-655 ng kg(-1)), perfluorooctanoate (150-390 ng kg(-1)), and perfluorononanoate (45-320 ng kg(-1)) at highest concentrations. Because of post depositional relocation processes within the peat cores, true or unbiased deposition fluxes (i.e., not affected by post depositional changes) could not be calculated. Apparent or biased deposition rates (i.e., affected by post depositional changes) were lower than measured/calculated deposition rates for similar urban or near-urban sites. Compared to PFAS production, PFAS concentration and deposition maxima were shifted about 30 years toward the past and some analytes were detected even in the oldest segments from the beginning of the 20th century. This was attributed to PFAS mobility in the peat profile. Considerable differences were observed between both peat cores and different PFASs. Overall, this study demonstrates that ombrotrophic bogs are not suited natural archives to provide authentic and reliable temporal trend data of historical atmospheric PFAS deposition. PMID:22680699

  15. 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.

  16. 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.

  17. Chlorodiscus natans Peter. & Hans. (Chlorophyceae from a mesotrophic peat bog in Lower Silesia (South-Western Poland

    Directory of Open Access Journals (Sweden)

    Jan Matula

    2011-04-01

    Full Text Available The paper concerns a very rare and poorly known species of green alga Chlorodiscus natans Petersen & Hansen, discovered in the peat bog "Brzeźnik" near Bolesławiec (Poland. This is the second stand so far discovered in the world. The collected material allowed complementing the knowledge on organization of colonies, morphology and way of hair development. The remaining features, particularly the structure of the cell, are in concordance with the hitherto diagnosis of that species. The paper presents problems connected with the taxonomic affiliation of the species and describes the ecological conditions of habitats occupied by this alga.

  18. Atmospheric Pb deposition in Spain during the last 4600 years recorded by two ombrotrophic peat bogs and implications for the use of peat as archive

    Energy Technology Data Exchange (ETDEWEB)

    Martinez Cortizas, A.; Garcia-Rodeja, E.; Pontevedra Pombal, X.; Novoa Munoz, J.C. [Departamento de Edafologia y Quimica Agricola, Faculdad de Biologia, Universidad de Santiago, Campus Sur E-15706, Santiago de Compostela (Spain); Weiss, D. [T.H. Huxley School, Imperial College, Prince Consort Road, SW7 2BP London (United Kingdom); Cheburkin, A. [EMMA Analytical Inc Canada, ON Elmvale (Canada)

    2002-06-20

    Two ombrotrophic peat bogs in Northwestern Spain provided a history of 4600 years of Pb accumulation. Highest Pb concentrations (84-87 {mu}g g{sup -1}) were found near the bogs' surface, but there were also other significant peaks (6-14 {mu}g g{sup -1}), indicating pre-industrial atmospheric pollution. The enrichment factors (EFs) in both cores show a remarkably similar record. Atmospheric Pb pollution dates back to at least approximately 2500 years ago, reaching a first maximum during the Roman period. For the last 300 years, Pb EFs significantly increased due to industrial development, but the uppermost samples of the bogs show decreasing Pb EFs, probably due to the phasing out of leaded gasoline. These results are also supported by 206Pb/207Pb isotope ratios, as they continuously decrease from ca. 3000 BP until 2000 BP (from 1.275 at 4070 14C years BP to 1.182), indicating the growing importance of non-radiogenic Pb released from Iberian ores by ancient mining. Peat samples at a 3-5-cm depth are even less radiogenic (206Pb/107Pb=1.157), indicating the strong influence of leaded gasoline. Despite the common history shared by the two bogs, striking differences were found for Pb enrichment, whether this was calculated by normalising to the Pb/Ti ratio of the upper continental crust or to the Pb/Ti ratios of peats from pre-anthropogenic times. This effect seems to be related to differences in Ti accumulation in both bogs, possibly due to physical fractionation of the airborne dust during wind transport. Enrichment has to be carefully considered when comparing the results obtained for different bogs, since our results suggest that normalising to crustal proportions is meaningless when the bulk of the deposition in an area is strongly influenced by short- and medium-range dust transport.

  19. Holocene Landscape Dynamics in the Ammer Rv. Catchment (Bavarian Alps) - Influence of extreme weather events and land use on soil erosion using peat bogs as geoarchives

    Science.gov (United States)

    Schwindt, Daniel; Manthe, Pierre; Völkel, Jörg

    2016-04-01

    Soil degradation and the loss of soil organic carbon (SOC) induced by erosion events significantly influence soils and fertility as parts of the ecosystem services and play an important role with regard to global carbon dynamics. Soil erosion is strongly correlated with anthropogenic land use since the Neolithic Revolution around 8.000 BP. Likewise the effect of extreme weather events on soil erosion is of great interest with regard to the recent climate change debate, predicting a strong increase of extreme weather events. Aim of this study is the reconstruction of the Holocene landscape dynamic as influenced by land use and climate conditions. In this study peat bogs containing layers of colluvial sediments directly correlated to soil erosion were used as geoarchives for landscape dynamics. A temporal classification of extreme erosion events was established by dating organic material via 14C within both, colluvial layers as well as their direct peat surroundings. Detection and characterization of peat bogs containing colluvial sediments was based on geomorphological mapping, the application of geophysical methods (ERT - electrical resistivity tomography, GPR - ground penetrating radar) and core soundings. Laboratory analysis included the analysis of particle sizes and the content of organic material. We investigated 16 peat bogs following the altitudinal gradient of the Ammer River from alpine and subalpine towards lowland environments. A deposition of colluvial material could be detected in 4 peat bogs, all situated in the lower parts of the catchment. The minerogenic entry into peat bogs occurred throughout the Holocene as revealed by radiocarbon dating. A distinct cluster of erosional events e.g. during the little ice age could not be detected. Therefore, soil erosion dynamics and the appearance of colluvial sediments within peat bogs must rather be regarded as an effect of land use, actually farming and crop cultivation, or small-scale morphodynamic like

  20. Carbon and Nitrogen Isotope Variation in Sphagnum from Peat Bogs in the Midwestern Us: Implications for Holocene Climate Reconstruction

    Science.gov (United States)

    Wong, D.; Paytan, A.; Jackson, S. T.

    2009-12-01

    A peat core taken from near the center of Minden Bog in Michigan, representing about 3500 years of accumulation was previously analyzed for plant macrofossils, colorimetric humification, and testate amoebae to yield three independent climate proxies. The data show the site to be sensitive to bog water table fluctuations and suggest that this may be related to regional climatic changes. We analyzed the carbon and nitrogen isotopes and the carbon-nitrogen ratios in the bulk peat samples and determined that the changes in these isotopes and ratios can be attributed to one or more of the following: (1) changes in the relative abundance of vegetation taxa in the site, (2) changes in the metabolism that impact isotope ratios in the vegetation contributing to the bulk organic, and (3) selective preservation and regeneration of specific organic compounds within the bulk organic matter. We analyzed the carbon and nitrogen isotopes and the carbon-nitrogen ratios in a specific taxum, Sphagnum, to differentiate between these mechanisms and relate the record to water level and climate in the region.

  1. Methane production and oxidation patterns along a hydrological gradient in Luther Bog, Ontario

    Science.gov (United States)

    Praetzel, Leandra; Berger, Sina; Blodau, Christian

    2016-04-01

    Methane emissions from natural peatlands contribute significantly to the global budget of atmospheric CH4. In the northern hemisphere, where climate models predict rising temperatures and precipitation rates, these emissions are likely to rise. So far, little is known about the change of processes of methane production and oxidation, which influence the total amount of methane emissions, in peatland soils under warmer and wetter climate conditions. Our work focuses on anaerobic CH4 production and aerobic CH4 oxidation processes along a hydrological gradient in an ombotrophic bog in Ontario, Canada that was induced by creation of a reservoir in 1952. Along this transect, four sites were established differing in hydrologic conditions and vegetation patterns. We examined depth profiles of CO2 and CH4 concentrations and delta 13C isotope ratios in the peat using silicon samplers, dialysis chambers and multi-level piezometers. Chamber flux measurements were used to determine carbon fluxes. Isotope mass balances were calculated based on 13C isotope ratios and concentration profiles. By this approach the contribution of anaerobic CH4 and CO2 production to the total ER flux and the amount of oxidised CH4 can be determined. In addition meteorological data, soil temperatures, moisture and water table levels were recorded. By raising data at different sites and dates and with the help of the additionally recorded parameters, we will be able to make predictions about changing CH4 production and oxidation processes due to changing climate conditions. Preliminary results show that CH4 concentrations in the soil profile are higher at the sites which are exposed to stronger water table fluctuations, whereas CO2 concentration levels are lower at these sites. At all sites, CO2 concentrations in the peat are increasing but CH4 profiles are fairly stable. Moreover, isotopic signatures of 13CH4 indicate that the importance of the production pathway changes with depth from acetoclastic

  2. Biogeochemical indicators of peatland degradation - a case study of a temperate bog in northern Germany

    Science.gov (United States)

    Kruger, J. P.; Leifeld, J.; Glatzel, S.; Szidat, S.; Alewell, C.

    2015-05-01

    Organic soils in peatlands store a great proportion of the global soil carbon pool and can lose carbon via the atmosphere due to degradation. In Germany, most of the greenhouse gas (GHG) emissions from organic soils are attributed to sites managed as grassland. Here, we investigated a land use gradient from near-natural wetland (NW) to an extensively managed (GE) to an intensively managed grassland site (GI), all formed in the same bog complex in northern Germany. Vertical depth profiles of δ13C, δ15N, ash content, C / N ratio and bulk density as well as radiocarbon ages were studied to identify peat degradation and to calculate carbon loss. At all sites, including the near-natural site, δ13C depth profiles indicate aerobic decomposition in the upper horizons. Depth profiles of δ15N differed significantly between sites with increasing δ15N values in the top soil layers paralleling an increase in land use intensity owing to differences in peat decomposition and fertilizer application. At both grassland sites, the ash content peaked within the first centimetres. In the near-natural site, ash contents were highest in 10-60 cm depth. The ash profiles, not only at the managed grassland sites, but also at the near-natural site indicate that all sites were influenced by anthropogenic activities either currently or in the past, most likely due to drainage. Based on the enrichment of ash content and changes in bulk density, we calculated the total carbon loss from the sites since the peatland was influenced by anthropogenic activities. Carbon loss at the sites increased in the following order: NW < GE < GI. Radiocarbon ages of peat in the topsoil of GE and GI were hundreds of years, indicating the loss of younger peat material. In contrast, peat in the first centimetres of the NW was only a few decades old, indicating recent peat growth. It is likely that the NW site accumulates carbon today but was perturbed by anthropogenic activities in the past. Together, all

  3. Biogeochemical indicators of peatland degradation – a case study of a temperate bog in northern Germany

    Directory of Open Access Journals (Sweden)

    J. P. Krüger

    2014-12-01

    Full Text Available Peatlands store a great proportion of the global soil carbon pool and can loose carbon via the atmosphere due to degradation. In Germany, most of the greenhouse gas emissions from organic soils are attributed to sites managed as grassland. Here we investigated a land-use gradient from near-natural wetland (NW to an extensively managed (GE to an intensively managed grassland site (GI, all formed in the same bog complex in northern Germany. Vertical depth profiles of δ13C, δ15N, ash content, C/N ratio, bulk density, as well as radiocarbon ages were studied to identify peat degradation and to calculate carbon loss. At all sites, including the near-natural site, δ13C depth profiles indicate aerobic decomposition in the upper horizons. Depth profiles of δ15Ndiffered significantly between sites with increasing δ15N values in the top layers with increasing intensity of use, indicating that the peat is more decomposed. At both grassland sites, the ash content peaked within the first centimeter. In the near-natural site, ash contents were highest in 10–60 cm depth. This indicates that not only the managed grasslands, but also the near-natural site, is influenced by anthropogenic activities, most likely due to the drainage of the surrounding area. However, we found very young peat material in the first centimeter of the NW, indicating recent peat growth. The NW site accumulates carbon today even though it is and probably was influenced by anthropogenic activities in the past indicated by δ13C and ash content depth profiles. Based on the enrichment of ash content and changes in bulk density, we calculated carbon loss from these sites in retrograde. As expected land use intensification leads to a higher carbon loss which is supported by the higher peat ages at the intensive managed grassland site. All investigated biogeochemical parameters together indicate degradation of peat due to (i conversion to grassland, (ii historical drainage as well as

  4. 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

  5. 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

  6. Effect of trap color and height on captures of blunt-nosed and sharp-nosed leafhoppers (hemiptera: cicadellidae) and non-target arthropods in cranberry bogs

    Science.gov (United States)

    A series of field experiments were conducted in cranberry bogs in 2006-2010 to determine adult attraction of the two most economically important leafhopper pests of cultivated Vaccinium spp. in the northeast USA, the blunt-nosed leafhopper, Limotettix vaccinii, and sharp-nosed leafhopper, Scaphytopi...

  7. The first record of the boreal bog species Drosera rotundifolia (Droseraceae) from the Philippines, and a key to the Philippine sundews

    NARCIS (Netherlands)

    Coritico, F.P.; Fleischmann, A.

    2016-01-01

    Drosera rotundifolia, a species of the temperate Northern Hemisphere with a disjunct occurrence in high montane West Papua, has been discovered in a highland peat bog on Mt Limbawon, Pantaron Range, Bukidnon on the island of Mindanao, Philippines, which mediates to the only other known tropical, Sou

  8. A Regional Comparison of the Long-Term Carbon Dynamics Within Maritime Peat Bogs Along the St. Lawrence North Shore, Northeastern Canada

    Science.gov (United States)

    Magnan, G.; Garneau, M.

    2013-12-01

    We have reconstructed the long-term carbon (C) dynamics within maritime bogs from two ecoclimatic regions between the Estuary (Baie-Comeau) and the Gulf of St. Lawrence (Havre-St.-Pierre) in northeastern Canada. The long-term average rates of C accumulation (LORCA) were calculated for eight peatlands. We also compared the Holocene variations in C sequestration between the peatlands to evaluate the influence of climate variability on their long-term C balance. The accumulation/decay processes were linked with changes in vegetation and water table depth. Overall, the LORCA decrease with the age of the peat deposits likely due to constant anoxic decay but they are significantly lower in Havre-St.-Pierre (16-46 g C m-2 yr-1) than in Baie-Comeau (53-68 g C m-2 yr-1). The regional differences in the LORCA reveal a pervasive climatic control on the long-term C balance. Our data suggest that the C accumulation in these bogs was driven by complex interactions between the peat accumulation/decay processes and the climate-mediated water table fluctuations. The higher C accumulation rates in the bogs of Baie-Comeau were promoted by stable ecohydrological conditions whereas the C balance in the bogs of Havre-St.-Pierre was more easily disrupted by past hydroclimatic changes especially during the Neoglacial cooling.

  9. Using a Thermokarst Bog Chronosequence to Examine Post-thaw Changes in Net Carbon Balance and the Interactions Between Permafrost, Vegetation, and Carbon

    Science.gov (United States)

    Manies, K.; Jones, M.; Waldrop, M. P.

    2015-12-01

    Northern forest soils and wetlands have served as carbon (C) sinks for thousands of years. The boreal region contains 50% of the world's soil organic C, with northern peatlands accounting for 30% of that pool. However, climate change in this region, in the form of warming air temperatures, has the potential to release a significant portion of this C due to changes in ecosystem structure and function. In particular, permafrost thaw in low-lying, moderately ice-rich areas results in the formation of collapse-scar bogs, dramatically altering the C cycle. Recent studies have shown that the transition from permafrost plateau to thermokarst bog results in the rapid loss of silvic (forest) peat, followed by a slow accumulation of C in post-thaw bog peat. Results from these studies suggest that this transition may turn these areas from net C sinks to C sources in the decades to centuries following thaw. Here we examine a bog chronosequence located within the Tanana River floodplain of Interior Alaska to determine if this pattern of C loss and gain holds true. Peat cores were taken to mineral soil from a permafrost plateau and three bogs with different ages of thaw (within the last several decades, within the last century, and within the past several centuries). All sites were located within the Bonanza Creek Long-term Ecological Research (LTER) site near Fairbanks, AK. We examined how the complex history of these thermokarst features can affect the C cycle. Macrofossil analysis reveals that most cores contained multiple cycles of permafrost aggradation and degradation, with the permafrost aggradation occurring epigenetically after peat initiated from a floodplain fen. Differences in vegetation communities that form peat, and the respective bulk densities associated with fens, permafrost plateaus, and collapse-scar bogs, resulted in different C accumulation rates. These data will provide insight into the fate of C within thermokarst bogs with complex permafrost histories in

  10. Geochemical and mineralogical composition of bog iron ore as a resource for prehistoric iron production - A case study of the Widawa catchment area in Eastern Silesia, Poland

    Science.gov (United States)

    Thelemann, Michael; Bebermeier, Wiebke; Hoelzmann, Philipp

    2016-04-01

    Spreading from the Near East in the declining Bronze Age from the 2nd millennium BCE onwards, the technique of iron smelting reached Eastern Silesia, Poland, in approximately the 2nd century BCE (pre-Roman Iron Age). At this time the region of the Widawa catchment area was inhabited by the Przeworsk culture. While the older moraine landscape of the study area lacks ores from geological rock formations, bog iron ores were relatively widespread and, due to their comparatively easy accessibility, were commonly exploited for early iron production. In this poster the mineralogical and elemental composition of local bog iron ore deposits and iron slag finds, as a by-product of the smelting process, are investigated. The crystalline mineralogical composition of local bog iron ores is dominated by quartz (SiO2) and goethite (α FeO(OH)), in contrast to slag samples in which fayalite (Fe2SiO4), wüstite (FeO) and quartz, with traces of goethite, represent the main minerals. Ores and slags are both characterized by notable hematite (Fe2O3), magnetite (Fe3O4) and maghemite (γ-Fe2O3) contents. Analyzed bog iron ore samples show iron contents of up to 64.9 mass% Fe2O3 (45.4 mass% Fe), whereas the iron contents of bloomery slags vary between 48.7 and 72.0 mass% FeO (37.9 and 56.0 mass% Fe). A principal component analysis of the element contents, which were quantified by portable energy-dispersive X-ray fluorescence spectrometry (p-ED-XRF), indicates local variations in the elemental composition. Our results show that bog iron ores are relatively widely distributed with spatially varying iron contents along the Widawa floodplain but present-day formation conditions (e.g. different ground-water levels) are negatively affected by modern land-use practices, such as agriculture and melioration measures.

  11. Methanotrophic activity and diversity in different Sphagnum magellanicum dominated habitats in the southernmost peat bogs of Patagonia

    Directory of Open Access Journals (Sweden)

    M. S. M. Jetten

    2011-09-01

    Full Text Available Sphagnum peatlands are important ecosystems in the methane cycle. Methanotrophs living in and on the Sphagnum mosses are able to act as a methane filter and thereby reduce methane emissions. We investigated in situ methane concentrations and the corresponding activity and diversity of methanotrophs in different Sphagnum dominated bog microhabitats. In contrast to the Northern Hemisphere peat ecosystems the temperate South American peat bogs are dominated by one moss species; Sphagnum magellanicum. This permitted a species-independent comparison of the different bog microhabitats. Potential methane oxidizing activity was found in all Sphagnum mosses sampled and a positive correlation was found between activity and in situ methane concentrations. Substantial methane oxidation activity (23 μmol CH4 gDW−1 day−1 was found in pool mosses and could be correlated with higher in situ methane concentrations (>35 μmol CH4 l−1 pore water. Little methanotrophic activity (4 gDW−1 day−1 was observed in living Sphagnum mosses from lawns and hummocks. Methane oxidation activity was relatively high (>4 μmol CH4 gDW−1 day−1 in Sphagnum litter situated at depths around the water levels and rich in methane. The total bacterial community was studied using 16S rRNA gene sequencing and the methanotrophic communities were studied using a pmoA microarray and a complementary pmoA clone library. The methanotrophic diversity was similar in the different habitats of this study and surprisingly comparable to the methanotrophic diversity found in peat mosses from the Northern Hemisphere. The pmoA microarray data indicated that both alpha- and gammaproteobacterial methanotrophs were present in all Sphagnum mosses, even in those mosses with a low initial methane oxidation activity. Prolonged incubation of Sphagnum mosses from lawn and hummock with methane revealed that the methanotrophic community present was viable and showed an increased activity within 15

  12. 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

  13. [Decline of Activity and Shifts in the Methanotrophic Community Structure of an Ombrotrophic Peat Bog after Wildfire].

    Science.gov (United States)

    Danilova, O V; Belova, S E; Kulichevskaya, I S; Dedysh, S N

    2015-01-01

    This study examined potential disturbances of methanotrophic communities playing a key role in reducing methane emissions from the peat bog Tasin Borskoye, Vladimir oblast, Russia as a result of the 2007 wildfire. The potential activity of the methane-oxidizing filter in the burned peatland site and the abundance of indigenous methanotrophic bacteria were significantly reduced in comparison to the undisturbed site. Molecular analysis of methanotrophic community structure by means of PCR amplification and cloning of the pmoAgene encoding particulate methane monooxygenase revealed the replacement of typical peat-inhabiting, acidophilic type II methanotrophic bacteria with type I methanotrophs, which are less active in acidic environments. In summary, both the structure and the activity of the methane-oxidizing filter in burned peatland sites underwent significant changes, which were clearly pronounced even after 7 years of the natural ecosystem recovery. These results point to the long-term character of the disturbances caused by wildfire in peatlands. PMID:27169243

  14. Interspecific differences in foliar 1 PAHs load between Scots pine, birch, and wild rosemary from three polish peat bogs.

    Science.gov (United States)

    Mętrak, Monika; Aneta, Ekonomiuk; Wiłkomirski, Bogusław; Staszewski, Tomasz; Suska-Malawska, Małgorzata

    2016-08-01

    Pine needles are one of the most commonly used bioindicators of polycyclic aromatic hydrocarbons (PAHs) in the environment. Therefore, the main objective of the current research was the assessment of PAHs accumulation potential of Scots pine (Pinus sylvestris L.) needles in comparison to wild rosemary (Rhododendron tomentosum Harmaja) and birch (Betula spp.) leaves. Our study was carried out on three peat bogs subjected to different degree of anthropopression, which gave us also the opportunity to identify local emission sources. Pine needles had the lowest accumulation potential from all the studied species. The highest accumulation potential, and hence carcinogenic potential, was observed for wild rosemary leaves. As far as emission sources are concerned, the most pronounced influence on atmospheric PAHs loads had traditional charcoal production, resulting in great influx of heavy PAHs. Observed seasonal changes in PAHs concentrations followed the pattern of winter increase, caused mainly by heating season, and summer decrease, caused mainly by volatilization of light PAHs. PMID:27393196

  15. Controls on suppression of methane flux from a peat bog subjected to simulated acid rain sulfate deposition

    Science.gov (United States)

    Gauci, Vincent; Dise, Nancy; Fowler, David

    2002-01-01

    The effect of acid rain SO42- deposition on peatland CH4 emissions was examined by manipulating SO42- inputs to a pristine raised peat bog in northern Scotland. Weekly pulses of dissolved Na2SO4 were applied to the bog over two years in doses of 25, 50, and 100 kg S ha-1 yr-1, reflecting the range of pollutant S deposition loads experienced in acid rain-impacted regions of the world. CH4 fluxes were measured at regular intervals using a static chamber/gas chromatographic flame ionization detector method. Total emissions of CH4 were reduced by between 21 and 42% relative to controls, although no significant differences were observed between treatments. Estimated total annual fluxes during the second year of the experiment were 16.6 g m-2 from the controls and (in order of increasing SO42- dose size) 10.7, 13.2, and 9.8 g m-2 from the three SO42- treatments, respectively. The relative extent of CH4 flux suppression varied with changes in both peat temperature and peat water table with the largest suppression during cool periods and episodes of falling water table. Our findings suggest that low doses of SO42- at deposition rates commonly experienced in areas impacted by acid rain, may significantly affect CH4 emissions from wetlands in affected areas. We propose that SO42- from acid rain can stimulate sulfate-reducing bacteria into a population capable of outcompeting methanogens for substrates. We further propose that this microbially mediated interaction may have a significant current and future effect on the contribution of northern peatlands to the global methane budget.

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

    Directory of Open Access Journals (Sweden)

    J.M. Schouwenaars

    2007-04-01

    Full Text Available 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 water stress so that adequate management measures may be applied. In the work reported here, the respective roles of the hydrophysical properties of the uppermost peat layer and micro-scale site conditions are investigated using a Soil-Water-Atmosphere-Plant (SWAP model, which simulates water table fluctuations and soil moisture conditions. The variables are: (a cover and thickness of the Sphagnum layer, (b microtopography (presence of open water, (c hydrophysical properties of the uppermost soil layer and (d rate of downward seepage. Data for the model are derived from field observations, from published literature, and from laboratory determinations of moisture characteristic curves and saturated and unsaturated hydraulic conductivity (k–h–Θ relationships for peat. The simulation indicates that microtopography and the thickness of the moss layer are the dominant factors affecting groundwater behaviour and the risk of water stress. Sphagnum layers a few centimetres thick should be relatively well supplied with water from the underlying peat but as the Sphagnum carpet thickens, water movement through the unsaturated zone to the growing capitula will become increasingly difficult. Sphagnum layers appear to be most vulnerable to water stress when they are 5–15 cm thick. Beyond this thickness, water stored within the Sphagnum layer itself begins to offset the decline in the flux from below, and thus to reduce the dependence of the water supply to the stem tips on the maintenance of hydraulic continuity with the water table. The results obtained using the model underline the close interdependence between Sphagnum development and the accompanying

  17. The first record of the boreal bog species Drosera rotundifolia (Droseraceae) from the Philippines, and a key to the Philippine sundews

    OpenAIRE

    Coritico, F.P.; Fleischmann, A.

    2016-01-01

    Drosera rotundifolia, a species of the temperate Northern Hemisphere with a disjunct occurrence in high montane West Papua, has been discovered in a highland peat bog on Mt Limbawon, Pantaron Range, Bukidnon on the island of Mindanao, Philippines, which mediates to the only other known tropical, Southern Hemisphere location in New Guinea and the closest known northern populations in southern Japan and south-eastern China. A dichotomous key to the seven Drosera species of the Philippines is gi...

  18. Peat-bog accumulation rate in the Andes of Tierra del Fuego and Patagonia (Argentina and Chile) during the last 43,000 years

    Energy Technology Data Exchange (ETDEWEB)

    Rabassa, J.; Heusser, C.J.; Coronato, A. (CADIC-CONICET, Ushuaia (Argentina))

    1989-01-01

    Profiles of biogenic deposits formed in peat-bogs and lakes of Tierra del Fuego and Patagonia have been analysed in order to ascertain their internal structure and the accumulation rate of organic matter. This rate, estimated between 0.5 y 0.7 mm/yr for the Late Quaternary, reflects, among other factors, climatic changes and the compaction processes of the sediments. 9 refs., 3 tabs., 3 figs.

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

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    C. Beyer

    2014-03-01

    Full Text Available 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

  20. 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

  1. 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

  2. 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.

  3. A Record of Moisture History in Hawaii since the Arrival of Humans Inferred from Testate Amoebae and Cladocera Fossils Preserved in Bog Sediments

    Science.gov (United States)

    Barrett, K.; Kim, S. H.; Hotchkiss, S.

    2015-12-01

    Around AD 800, Polynesians arrived on the Hawaiian Islands where they expanded and intensified distinct agricultural practices in the islands' wet and dry regions. Dryland farming productivity in particular would have been sensitive to atmospheric rearrangements of the ENSO and PDO systems that affect rainfall in Hawaii. The few detailed terrestrial paleoclimate records in Hawaii are mainly derived from vegetation proxies (e.g. pollen, seeds, fruits, and plant biomarkers) which are heavily influenced by widespread landscape modification following human arrival. Here we present initial results of an independent paleomoisture proxy: fossil remains of moisture-sensitive testate amoebae (Protozoa: Rhizopoda) and cladocera (water fleas) preserved in continuous bog sediments on Kohala Volcano uplsope of the ancient Kohala agricultural field system, one of the largest dryland field systems in Hawaii. Hydrologic conditions inferred from testate amoebae and cladoceran fossil assemblages correlate with observed decadal moisture regimes in Hawaii and state changes of the PDO system during the last century. Testate ameoabe and cladoceran fossils in older sediments reveal an alternating history of very wet, lake-forming conditions on the bog surface to periods when bog soils were much drier than today's, demonstrating that this method can be paired with vegetation proxies to provide a better understanding of hydroclimate variability in prehistoric Hawaii.

  4. 13C/Palynological evidence of differential residence times of organic carbon prior to its sedimentation in East African Rift Lakes and peat bogs

    Science.gov (United States)

    Hillaire-Marcel, Claude; Aucour, Anne-Marie; Bonnefille, Raymonde; Riollet, Guy; Vincens, Annie; Williamson, David

    Most terrestrial plants producing large amounts of organic matter in the East African Rift follow the Calvin (C3) photosynthetic pathway. Their end products have δ13C values of ca. -27 ± 2‰ (vs. PDB). On the contrary, most Cyperaceae (notably Cyperus papyrus and C. latifolius) are characterized by higher 13C contents ° 13C = -10.5 ± 1‰ ) in relation to their Hatch and Slack (C4) photosynthetic cycle. In consequence, δ13C values in total organic matter (TOM) from peat bog or lake cores essentially responded to the proportion of detritus from C4-Cyperaceae. Immediate evidence of the development or disappearance of Cyperaceae around lake margins or in peat bogs can be found in pollen assemblages. Lag times between pollen signals and correlative ° 13C shifts in TOM from cores are therefore indicative of the residence time of organic matter prior to its sedimentation. Delayed sedimentation of TOM will result in 14C anomalies which depend on several parameters, most of them being site specific as shown by examples from a peat bog in Burundi and from southern Lake Tanganyika. An independent assessment of the chronology by high resolution paleomagnetic correlations indicates a ca. 1.5 ka apparent 14C age of TOM in Lake Tanganyika at the Pleistocene-Holocene transition.

  5. The Brenner Moor - A saline bog as a source for halogenated and non-halogenated volatile compounds

    Science.gov (United States)

    Krause, T.; Studenroth, S.; Furchner, M.; Hoffman, A.; Lippe, S.; Kotte, K.; Schöler, H. F.

    2012-04-01

    The Brenner Moor is a small bog in the catchment area of the river Trave located in Schleswig-Holstein, North Germany, between Baltic and North Sea. The bog is fed by several saline springs with chloride concentrations up to 15 g/L. The high chloride concentrations and the high organic content of the peat make the Brenner Moor an ideal source for the abiotic formation of volatile organic halogenated compounds (VOX). VOX play an important role in the photochemical processes of the lower atmosphere and information on the atmospheric input from saline soils like the Brenner Moor will help to understand the global fluxes of VOX. Soil samples were taken in spring 2011 from several locations and depths in the vicinity of the Brenner Moor. The samples were freeze-dried, ground and incubated in water emphasising an abiotic character for the formation of volatile organic compounds. 1,2-dichloroethane and trichloromethane are the main halogenated compounds emitted from soils of the Brenner Moor. The abiotic formation of trichloromethane as well as other trihalomethanes has been part of intensive studies. A well known source is the decarboxylation of trichloroacetic acid and trichloroacetyl-containing compounds to trichloromethane [1]. Huber et al. discovered another pathway in which catechol, as a model compound for organic substances, is oxidised under Fenton-like conditions with iron(III), hydrogen peroxide and halides to form trihalomethanes [2]. Besides the halogenated compounds, the formation of sulphur compounds such as dimethyl sulfide and dimethyl disulfide and several furan derivatives could be detected which also have an impact on atmospheric chemistry, especially particle formation of clouds. Furan, methylfuran and dimethylfuran are compounds that can be obtained under Fenton-like oxidation from catechol, methyl- and dimethylcatechol and are known to be produced in natural soils [3]. A novel class of furan derivatives that are formed under abiotic conditions from

  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. Relationships among the water table depth, water and surface elevations, and the composition of vegetation in a temperate hummocky, ombrogenic, oligotrophic raised shrub bog

    Science.gov (United States)

    Roulet, Nigel; Wilson, Paul; Malhora, Avni

    2016-04-01

    Microtopography, such as hummocks and hollows, pools, ridges and lawns are features that are believed to be a consequence of feedbacks among the local hydrology and the production and decomposition of organic material. To deductively test some of the postulates derived from several theoretical studies of the development of patterning on peatlands, over two consecutive years we examined the spatial and temporal relationships among the hummock - hollow microtopography, water table depths (WTD) and water elevations (WTE) in a raised, ombrotrophic bog (Mer Bleue, Canada) that has extensive and well developed microtopography. In each of two 20 x 20 m plots we measured the surface elevation at more than 1,000 points, the WTDs manually every two to three weeks at 100 wells located on a 2 x 2 m grid, and WTDs continuously at more than 20 sites at adjacent hummocks and hollows. In addition to the physical measurements we also measured the spatial pattern of the vegetation communities. The average difference in elevation between the hummocks and hollows was ~ 0.5 m and as was expected the WTDs were shallower in the hollows than under the hummocks. The spatial variability in WTDs over time was very consistent. We tested the coherence between WTDs and surface elevation and found for a total of 46 spatial surveys over the two years and both plots the slopes from mixed modelled regressions were not significantly different for over 80% of the surveys. The difference in WTEs in adjacent microtopographic features (i.e. water levels referenced to a common datum), which determine the hydraulic gradients between hummocks and hollows, was quite small. The small gradients and the consistent coherence between WTDs and surface elevation suggests there is little lateral movement of water among the microtopographic features. The vegetation analysis showed the plot closer to the center, the apex, of the bog had stronger relationships among WTD-microtopography and vegetation than a plot

  8. Biometrical study of some individuals chosen from Pinus mugo turra populations in the peat bog "Bór na Czerwonem"

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    Alina Bączkiewicz

    2014-02-01

    Full Text Available Sixteen individuals were sampled for study of variation in 17 anatomical and morphological characters. Only individuals of low polycormic growth (trait typical for Pinus mugo Turra connected with incurved one-year-cone stipes (a similar situation exists in Pinus sylvestris L. were chosen, thus the sample studied cannot be treated as a random one. It has been shown by multivariate statistical analysis that these 16 individuals are quite different from each other, Mahalanobis'generalized distances between them being nearly 50% significantly different from 0. The sample studied in this respect is distinctly different from pure stands of both putative parental species (i.e. Pinus mugo and P. sylvestris. Every plant studied shows a different combination of traits typical (or nearly typical for both the above-mentioned species and traits that are truly intermediate between them. The results support the frequently expressed opinion that the mountain pine population from the peat bog "Bór na Czerwonem" is, in fact, a hybrid swarm formed by hybridization between Pinus mugo and Pinus sylvestris.

  9. Isoenzymatic differentiation in putative hybrid swarm population (Pinus mugo Turra x P. sylvestris L. from "Torfowisko Zieleniec" peat-bog

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    Anna Siedlewska

    2014-02-01

    Full Text Available Isoenzyme variability of eight groups of individuals from different parts of putative hybrid swarm population (P. mugo Turra x P. sylvestris L. from "Torfowisko Zieleniec" peat-bog complex was studied at ten enzymatic loci. Differences in allelic frequencies distribution among particular samples of the Zieleniec population were statistically significant at 9 loci, as shown by G2- statistics. Chi-square test indicated that in each of studied subpopulations frequencies of alleles at some loci (2-5 differed significantly from frequencies expected for a homogeneous population. Heterozygosity values and also a genotypic polymorphism in studied population confirmed the existence of large genetic variation. Wright's fixation indices (F showed some excess of homozygotes in majority studied groups of individuals, notably higher in some subpopulations. Gene diversity coefficient for 8 subpopulations was high (GST=9.4%. However, when MDH C locus was excluded from the calculation, its value decreased to 2.8%. Presented data demonstrated notable differentiation of subpopulations within studied pine population, comparable with the differentiation among different populations of coniferous species.

  10. Mid and late Holocene dust deposition in western Europe: the Misten peat bog (Hautes Fagnes – Belgium

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    M. Allan

    2013-05-01

    Full Text Available Dust deposition in southern Belgium is estimated from the geochemical signature of an ombrotrophic peatland. The Rare Earth Elements (REE and lithogenic elements concentrations, as well as Nd isotopes, were determined by HR-ICP-MS and MC-ICP-MS respectively, in along a ~6 m peat section covering 5300 yr, from 30 BC to 5300 BC dated by the 14C method. Changes in REE concentration in the peat correlate with those of Ti, Al, Sc and Zr that are lithogenic conservative elements, suggesting that REE are immobile in the studied peat bogs and can be used as tracers of dust deposition. Peat humification and testate amoebae were used to evaluate hydroclimatic conditions. The range of dust deposition varied from 0.03 to 4.0 g m−2 yr−1. The highest dust fluxes were observed from 800 to 600 BC and from 3200 to 2800 BC and correspond to cold periods. The εNd values show a large variability of −5 to −13, identifying three major sources of dusts: local soils, distal volcanic and desert particles.

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

    International Nuclear Information System (INIS)

    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.

  12. 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

  13. 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.

  14. Potentials and problems of building detailed dust records using peat archives: An example from Store Mosse (the "Great Bog"), Sweden

    Science.gov (United States)

    Kylander, Malin E.; Martínez-Cortizas, Antonio; Bindler, Richard; Greenwood, Sarah L.; Mörth, Carl-Magnus; Rauch, Sebastien

    2016-10-01

    Mineral dust deposition is a process often overlooked in northern mid-latitudes, despite its potential effects on ecosystems. These areas are often peat-rich, providing ample material for the reconstruction of past changes in atmospheric deposition. The highly organic (up to 99% in some cases) matrix of atmospherically fed mires, however, makes studying the actual dust particles (grain size, mineralogy) challenging. Here we explore some of the potentials and problems of using geochemical data from conservative, lithogenic elements (Al, Ga, Rb, Sc, Y, Zr, Th, Ti and REE) to build detailed dust records by using an example from the 8900-yr peat sequence from Store Mosse (the "Great Bog"), which is the largest mire complex in the boreo-nemoral region of southern Sweden. The four dust events recorded at this site were elementally distinct, suggesting different dominant mineral hosts. The oldest and longest event (6385-5300 cal yr BP) sees a clear signal of clay input but with increasing contributions of mica, feldspar and middle-REE-rich phosphate minerals over time. These clays are likely transported from a long-distance source (clays and heavy minerals is inferred. Elemental mass accumulation rates reflect these changes in mineralogy where the relative importance of the four dust events varies by element. The broad changes in major mineral hosts, grain size, source location and approximated net dust deposition rates observed in the earlier dust events of longer duration agree well with paleoclimatic changes observed in northern Europe. The two most recent dust events are much shorter in duration, which in combination with evidence of their local and regional character, may explain why they have not been seen elsewhere.

  15. Assessing the controls of the snow energy balance in a shrub-covered bog in eastern Ontario, Canada

    Science.gov (United States)

    Carey, S. K.; Knox, S.; Humphreys, E.

    2012-12-01

    The objectives of this study were to measure and evaluate the energy balance of a snowpack in a northern peatland, with a particular emphasis on the ground heat flux (G), and to evaluate the performance of a point energy and mass balance snowmelt model (SNOBAL) in peatland ecosystems. G is typically considered a small component of the snowpack energy balance (EB) when compared with radiative and turbulent fluxes. However, in environments where the soil temperature remains above freezing throughout the winter, G may be an important energy input to the snowpack. For direct assessment of the role of G in the snow energy budget of such an environment, the EB components of the snowpack at the Mer Bleue bog, a northern peatland, were directly measured and modelled using SNOBAL during the 2009-2010 winter. An 8 m tower mounted with a net radiometer, closed-path eddy covariance system, and supporting hydrometeorological instruments were used to quantify each form of energy transfer to the snowpack. In addition, snow surveys were conducted to determine snow depth, density, and snow water equivalent. When integrated over the pre-melt period, simulated and measured G proved to be a large contributor to the EB (25%). Net radiation and G were somewhat under-predicted by SNOBAL, whereas turbulent fluxes (especially latent heat fluxes, LE) were considerably over-predicted. G calculated by SNOBAL was found to be sensitive to the temperature gradient between the soil and the lower layer of the snowpack, whereas simulated turbulent fluxes were sensitive to the parameterization chosen to estimate roughness lengths for heat and water vapour.

  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. PMID:26971209

  17. Dom Export from Coastal Temperate Bog Forest Watersheds to Marine Ecosystems: Improving Understanding of Watershed Processes and Terrestrial-Marine Linkages on the Central Coast of British Columbia

    Science.gov (United States)

    Oliver, A. A.; Giesbrecht, I.; Tank, S. E.; Hunt, B. P.; Lertzman, K. P.

    2014-12-01

    The coastal temperate bog forests of British Columbia, Canada, export high amounts of dissolved organic matter (DOM) relative to the global average. Little is known about the factors influencing the quantity and quality of DOM exported from these forests or the role of this terrestrially-derived DOM in near-shore marine ecosystems. The objectives of this study are to better understand patterns and controls of DOM being exported from bog forest watersheds and its potential role in near-shore marine ecosystems. In 2013, the Kwakshua Watershed Ecosystems Study at Hakai Beach Institute (Calvert Island, BC) began year-round routine collection and analysis of DOM, nutrients, and environmental variables (e.g. conductivity, pH, temperature, dissolved oxygen) of freshwater grab samples from the outlets of seven watersheds draining directly to the ocean, as well as near-shore marine samples adjacent to freshwater outflows. Dissolved organic carbon (DOC) varied across watersheds (mean= 11.45 mg L-1, sd± 4.22) and fluctuated synchronously with seasons and storm events. In general, higher DOC was associated with lower specific UV absorbance (SUVA254; mean= 4.59 L mg-1 m-1, sd± 0.55). The relationship between DOC and SUVA254 differed between watersheds, suggesting exports in DOM are regulated by individual watershed attributes (e.g. landscape classification, flow paths) as well as precipitation. We are using LiDAR and other remote sensing data to examine watershed controls on DOC export. At near-shore marine sites, coupled CTD (Conductivity Temperature Depth) and optical measures (e.g. spectral slopes, slope ratios (SR), EEMs), showed a clear freshwater DOM signature within the system following rainfall events. Ongoing work will explore the relationship between bog forest watershed attributes and DOM flux and composition, with implications for further studies on biogeochemical cycling, carbon budgets, marine food webs, and climate change.

  18. Demographic and genetic status of an isolated population of bog turtles (Glyptemys muhlenbergii): Implications for managing small populations of long-lived animals

    Science.gov (United States)

    Pittman, Shannon E.; King, T.L.; Faurby, S.; Dorcas, M.E.

    2011-01-01

    In this study, we sought to determine the population stability and genetic diversity of one isolated population of the federally-threatened bog turtle (Glyptemys muhlenbergii) in North Carolina. Using capture-recapture data, we estimated adult survival and population growth rate from 1992 to 2007. We found that the population decreased from an estimated 36 adult turtles in 1994 to approximately 11 adult turtles in 2007. We found a constant adult survival of 0. 893 (SE = 0. 018, 95% confidence interval, 0. 853-0. 924) between 1992 and 2007. Using 18 microsatellite markers, we compared the genetic status of this population with five other bog turtle populations. The target population displayed allelic richness (4. 8 ?? 0. 5) and observed heterozygosity (0. 619 ?? 0. 064) within the range of the other bog turtle populations. Coalescent analysis of population growth rate, effective population size, and timing of population structuring event also indicated the genetics of the target population were comparable to the other populations studied. Estimates of effective population size were a proportion of the census size in all populations except the target population, in which the effective population size was larger than the census size (30 turtles vs. 11 turtles). We attribute the high genetic diversity in the target population to the presence of multiple generations of old turtles. This study illustrates that the demographic status of populations of long-lived species may not be reflected genetically if a decline occurred recently. Consequently, the genetic integrity of populations of long-lived animals experiencing rapid demographic bottlenecks may be preserved through conservation efforts effective in addressing demographic problems. ?? 2011 Springer Science+Business Media B.V.

  19. Four thousand years of atmospheric Pb, Cd and Zn deposition recorded by the ombrotrophic peat bog of Penido Vello (northwestern Spain)

    Energy Technology Data Exchange (ETDEWEB)

    Martinez-Cortizas, A.; Pontevedra-Pombal, X.; Novoa-Munoz, J.C.; Garcia-Rodeja, E. [Universidad de Santiago de Compostila, Santiago de Compostela (Spain). Dept. de Edafologia y Quimica Agricola

    1997-12-01

    The Northwest Iberian Peninsula is a mid-latitude oceanic region with areas where different types of bogs are frequent or abundant. The ombrotrophic nature of some bogs make them suitable for the study of accumulation patterns of heavy metals. One of these bogs, Penido Vello, was sampled to a depth of 2.5 m and analyzed in detail for its physico-chemical properties and Pb, Zn and Cd concentrations. Ash and organic carbon content, Ca/Mg molar ratios and a number of other characteristics support an ombrotrophic interpretation of the core. Concentrations of Pb, Zn and Cd were measured, showing important variations in the core. While Zn and Cd are concentrated mainly in the upper sections of the core with minor changes with depth, the Pb profile shows significant peaks in the deeper layers suggesting pre-industrial atmospheric pollution. Enrichment factors (EFs) calculated by normalising to Al correlated well with those calculated by normalising to Ti. Maximum EFs are 33.56 and 52 for Pb, Zn and Cd respectively. While for Pb these values are comparable to those obtained by other authors, maximum Zn EFs are greater than those mentioned in the literature and may be attributed to the emissions of a nearby coal-burning power plant. At least for Pb the accumulation pattern suggests that atmospheric pollution can be dated back some 2800 years, and that pollution increased steadily since the Iron Age to reach considerably elevated levels, up to 5 times the `background`, during the Roman Empire. Changes in Pb emissions through times are in good accord with the prehistorical and historical record of the Iberian Peninsula. 54 refs., 8 figs., 1 tab.

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

    OpenAIRE

    Magdalena Pogorzelec; Barbara Banach

    2012-01-01

    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 spe...

  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. Groundwater flow with energy transport and water-ice phase change: Numerical simulations, benchmarks, and application to freezing in peat bogs

    Science.gov (United States)

    McKenzie, J.M.; Voss, C.I.; Siegel, D.I.

    2007-01-01

    In northern peatlands, subsurface ice formation is an important process that can control heat transport, groundwater flow, and biological activity. Temperature was measured over one and a half years in a vertical profile in the Red Lake Bog, Minnesota. To successfully simulate the transport of heat within the peat profile, the U.S. Geological Survey's SUTRA computer code was modified. The modified code simulates fully saturated, coupled porewater-energy transport, with freezing and melting porewater, and includes proportional heat capacity and thermal conductivity of water and ice, decreasing matrix permeability due to ice formation, and latent heat. The model is verified by correctly simulating the Lunardini analytical solution for ice formation in a porous medium with a mixed ice-water zone. The modified SUTRA model correctly simulates the temperature and ice distributions in the peat bog. Two possible benchmark problems for groundwater and energy transport with ice formation and melting are proposed that may be used by other researchers for code comparison. ?? 2006 Elsevier Ltd. All rights reserved.

  4. 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

    2011-04-01

    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.

  5. Experimental nitrogen, phosphorus, and potassium deposition decreases summer soil temperatures, water contents, and soil CO2 concentrations in a northern bog

    Science.gov (United States)

    Wendel, S.; Moore, T.; Bubier, J.; Blodau, C.

    2011-03-01

    Ombrotrophic peatlands depend on airborne nitrogen (N), whose deposition has increased in the past and lead to disappearance of mosses and increased shrub biomass in fertilization experiments. The response of soil water content, temperature, and carbon gas concentrations to increased nutrient loading is poorly known and we thus determined these data at the long-term N fertilization site Mer Bleue bog, Ontario, during a two month period in summer. Soil temperatures decreased with NPK addition in shallow peat soil primarily during the daytime (t-test, p fertilized treatments, the mean soil temperatures at 5 cm depth decreased by 1.3 °C and by 4.7 °C (standard deviation 0.9 °C) at noon. Water content was most strongly affected by within-plot spatial heterogeneity but also responded to both N and PK load according to RMANOVA (p < 0.05). Overall, water content and CO2 concentrations in the near-surface peat (t-test, p < 0.05) were lower with increasing N load, suggesting more rapid soil gas exchange. The results thus suggest that changes in bog ecosystem structure with N deposition have significant ramifications for physical parameters that in turn control biogeochemical processes.

  6. 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

    International Nuclear Information System (INIS)

    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 14C and 210Pb 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

  7. A flooded bog

    OpenAIRE

    French, Percy (Irish painter, draftsman, and illustrator, 1854-1920)

    2000-01-01

    Percy French was a graduate of Trinity College, Dublin. On termination of his employment as Cavan Board of Works Engineer in the mid 1880s, he devoted himself to composing, singing and watercolour painting. He often utilized both wet and dry brush techniques and specialized in mists and moors.

  8. Application of soil magnetometry on peat-bogs and soils in areas affected by historical and prehistoric ore mining and smelting.

    Science.gov (United States)

    Magiera, Tadeusz; Mendakiewicz, Maria; Szuszkiewicz, Marcin; Chrost, Leszak

    2015-04-01

    The valleys of upper Brynica and Stoła located in northern part of Upper Silesia were areas of historical human activities since prehistoric times. Historically confirmed mining and smelting of iron, silver and lead ores on this areas has been dated back to early Middle Ages, however recently some geochemical and radiometric analyses suggest even prehistoric time of such activities. The aim of this study was to check if it is possible to find any magnetic signal suggesting such activities in peat-bogs and soils of this area. This magnetic properties would be a result of presence of historical Technogenic Magnetic Particles (TMPs) arisen during the primitive smelting processes in the past. Many different types of TMPs were separated from the depth of 15-30 cm of soil profiles and also were present in deeper parts of peat-bogs accompanied by fine charcoal particles. The peat-bog horizons dated by radiocarbon (C14) for 2000 BC were contaminated by some heavy metals (Cu, Zn, Cd, Ag, Pb, Mn, Fe, Sr, Sc) and slightly increased magnetic susceptibility signal was also observed. On the base of soil surface magnetic measurement using MS2D Bartington sensor complemented by magnetic gradiometer system Grad 601-02 for the deeper soil penetration, some local magnetic anomalies were detected. In areas of local 'hot spots', the vertical cores up to 30 cm in depth were collected using the HUMAX core sampler. Vertical distribution of magnetic susceptibility along the cores was measured in the laboratory using the MS2C Bartington core sensor. The core section with increased susceptibility values were analyzed and TMPs were separated using a hand magnet. The separation of fine fraction of TMPs was carried out in an ultrasonic bath from the fine soil material suspended in isopropanol to avoid their coagulation. Irregular ceramic particles, ash and ore particles, as well as strong magnetic particles of metallic iron; all with diameter up to 10 mm and almost regular shape and rounded

  9. Nutrient load can lead to enhanced CH4 fluxes through changes in vegetation, peat surface elevation and water table depth in ombrotrophic bog

    Science.gov (United States)

    Juutinen, Sari; Bubier, Jill; Larmola, Tuula; Humphreys, Elyn; Arnkil, Sini; Roy, Cameron; Moore, Tim

    2016-04-01

    Atmospheric nitrogen (N) deposition has led to nutrient enrichment in wetlands, particularly in temperate areas, affecting plant community composition, carbon (C) cycling, and microbial dynamics. It is vital to understand the temporal scales and mechanisms of the changes, because peatlands are long-term sinks of C, but sources of methane (CH4), an important greenhouse gas. Rainwater fed (ombrotrophic) bogs are considered to be vulnerable to nutrient loading due to their natural nutrient poor status. We fertilized Mer Bleue Bog, a Sphagnum moss and evergreen shrub-dominated ombrotrophic bog near Ottawa, Ontario, now for 11-16 years with N (NO3 NH4) at 0.6, 3.2, and 6.4 g N m-2 y-1 (~5, 10 and 20 times ambient N deposition during summer months) 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 CH4 fluxes with static chambers weekly from May to September 2015 and peat samples were incubated in laboratory to measure CH4 production and consumption potentials. Methane fluxes at the site were generally low, but after 16 years, mean CH4 emissions have increased and more than doubled in high nitrogen addition treatments if P and K input was also increased (3.2 and 6.4 g N m-2yr-1 with PK), owing to drastic changes in vegetation and soil moisture. Vegetation changes include a loss of Sphagnum moss and introduction of new species, typical to minerogenic mires, which together with increased decomposition have led to decreased surface elevation and to higher water table level relative to the surface. The trajectories indicate that the N only treatments may result in similar responses, but only over longer time scales. Elevated atmospheric deposition of nutrients to peatlands may increase loss of C not only due to changes in CO2 exchange but also due to enhanced CH4 emissions in peatlands through a complex suite of feedbacks and interactions

  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)

    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 210Pb and 137Cs 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 210Pb and 137Cs decreased with the depth in both of the two sample cores. The 210Pb chronologies were established using the constant rate of supply model (CRS) and are in good agreement with the 137Cs time marker. Recent atmospheric 210Pb 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. Deciphering human-climate interactions in ombrotrophic peat record : REE, Nd and Pb isotope signatures of dust supplies over the last 2500 years (Misten bog, Belgium)

    Science.gov (United States)

    Fagel, Nathalie; Allan, Mohamed; Le Roux, Gael; Mattielli, Nadine; Piotrowska, Natalia; Sikorski, Jarek

    2013-04-01

    A core of 173 cm of ombrotrophic Misten peat bog from the Hautes-Fagnes Plateau in Eastern Belgium provides a record of Rare Earth Elements (REE) deposition allowing to trace dust fluxes in West Europe during the historical record (last 2500 years). REE and lithogenic element analyses, as well as the Nd isotopes, were performed by HR-ICP-MS and MC-ICP-MS, respectively in peat layers dated by 210Pb and 14C. The parallel variations of REE concentration with lithogenic conservative elements confirms that REE are immobile in the studied peat bog and can be used as tracers of dust deposition. Dust fluxes show pronounced increase at BC300, AD600, 1000AD, 1200AD and from 1700AD, recording either influence of human activities (regional erosion due to forest clearing and soil cultivation activities) or local and regional climate changes. Using Nd isotope allows to decipher between local and distal causes. The ENd variability (-13 to -9) is interpreted by a mixing between dust sources from local soils and desert particles. Three periods characterised by dominant-distal sources (at 320AD, 1000 AD and 1700AD) are consistent with local wetter intervals as indicated by lower humification degree. Local erosion prevails durier drier (higher humification) intervals (-100AD, 600AD). On a global scale more distal supplies are driven during colder periods, in particular Oort and Maunder minima. Combining geochemical elementary content and isotope data in ombrotrophic peat allows to decipher between dust flux changes related to human and climate forcing.

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

    Energy Technology Data Exchange (ETDEWEB)

    Bao, K.; Xia, W.; Lu, X.; Wang, G. [Chinese Academy of Sciences, Changchun (China). Key Laboratory of Wetland Ecology & Environment

    2010-09-15

    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 {sup 210}Pb and {sup 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 {sup 210}Pb and {sup 137}Cs decreased with the depth in both of the two sample cores. The {sup 210}Pb chronologies were established using the constant rate of supply model (CRS) and are in good agreement with the {sup 137}Cs time marker. Recent atmospheric {sup 210}Pb flux in Great Hinggan Mountains peat bog was estimated to be 337 Bq m{sup -2} y{sup -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{sup -2} y{sup -1} with a range of Pb concentration of 14-262 {mu} g g{sup -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.

  13. Uptake of radioiodide by Paenibacillus sp., Pseudomonas sp., Burkholderia sp. and Rhodococcus sp. isolated from a boreal nutrient-poor bog.

    Science.gov (United States)

    Lusa, Merja; Lehto, Jukka; Aromaa, Hanna; Knuutinen, Jenna; Bomberg, Malin

    2016-06-01

    Radionuclides, like radioiodine ((129)I), may escape deep geological nuclear waste repositories and migrate to the surface ecosystems. In surface ecosystems, microorganisms can affect their movement. Iodide uptake of six bacterial strains belonging to the genera Paenibacillus, Pseudomonas, Burkholderia and Rhodococcus isolated from an acidic boreal nutrient-poor bog was tested. The tests were run in four different growth media at three temperatures. All bacterial strains removed iodide from the solution with the highest efficiency shown by one of the Paenibacillus strains with >99% of iodide removed from the solution in one of the used growth media. Pseudomonas, Rhodococcus and one of the two Paenibacillus strains showed highest iodide uptake in 1% yeast extract with maximum values for the distribution coefficient (Kd) ranging from 90 to 270L/kg DW. The Burkholderia strain showed highest uptake in 1% Tryptone (maximum Kd 170L/kg DW). The Paenibacillus strain V0-1-LW showed exceptionally high uptake in 0.5% peptone +0.25% yeast extract broth (maximum Kd>1,000,000L/kg DW). Addition of 0.1% glucose to the 0.5% peptone +0.25% yeast extract broth reduced iodide uptake at 4°C and 20°C and enhanced iodide uptake at 37°C compared to the uptake without glucose. This indicates that the uptake of glucose and iodide may be competing processes in these bacteria. We estimated that in in situ conditions of the bog, the bacterial uptake of iodide accounts for approximately 0.1%-0.3% of the total sorption of iodide in the surface, subsurface peat, gyttja and clay layers. PMID:27266299

  14. The impact of 90 years of drainage works on some chemical properties of raised peat bog organic soils - case study from valley of the Upper San river in Polish Bieszczady Mts. (Eastern Carpathians).

    Science.gov (United States)

    Stolarczyk, Mateusz

    2016-04-01

    Wetland ecosystems, including raised peat bogs are characterized by a specific water conditions and unique vegetation, which makes peatland highly important habitats due to protection of biodiversity. Transformation of peat bog areas is particularly related to changes in the environment e.g. according to reclamation works. Drainage of peatlands is directly associated to the decrease of groundwater levels and lead to a number of changes in the chemical and physical properties of peat material, included contents of exchangeable cations in the surface layers of peat soils in the decession phase of peat development and release above compounds from the soil to ground or surface waters. The aim of the research was to determine the impact of extended drainage works on chemical composition of sorption complex of raised peat bog organic soils and identification the potential environmental effects of alkaline cations leaching to the surface waters. Research was carried out on the peat bogs located in the Upper San valley in Polish Bieszczady Mts. (Eastern Carpathians). Soil samples used in this study were collected from 3 soil profiles in 10 or 20 cm intervals to the approximately 130 cm depth. Laboratory analyses included determination of basic properties of organic material such as the degree of peat decomposition, ash content, soil pH and carbon, hydrogen, nitrogen concentrations. Additionally the amount of alkaline cations, exchangeable and extractable acidity was determined. Furthermore, the degree of saturation of the sorption complex with alkaline cations (V) and cation exchange capacity (CEC) are calculated. In order to evaluate the impact of the examined peat bog to the environment, also water samples were collected and ions composition was measured. The obtained results show that studied organic soils are oligotrophic and strongly acidic. In the case of organic material related to decession phase of peat development, as a result of the lengthy drainage works

  15. 雨养沼泽泥炭腐植酸的性质和结构%Properties and Structure of Raised Bog Peat Humic Acids

    Institute of Scientific and Technical Information of China (English)

    Maris Klavins; Oskars Purmalis; 韩征; 赵红艳(译)

    2014-01-01

    腐植酸类物质是土壤、泥炭和自然水体中有机物的主要成分,其来源不同,结构和性质也不同。本研究阐述了雨养沼泽泥炭腐植酸的性质,评估了泥炭剖面内腐植酸的均质性,并研究了泥炭腐殖化程度对腐植酸性能的影响。结果表明,以不同来源的苔藓为主的雨养沼泽植物对泥炭腐植酸结构的影响较大。泥炭腐植酸的成岩作用程度介于活有机体和煤炭之间,当碳水化合物、氨基酸等被破坏后,耐分解的芳烃和多环芳烃结构出现,泥炭腐植酸的结构趋于形成。然而,与土壤、水体和其他腐植酸相比,泥炭腐植酸的芳香性较低。相对而言,雨养沼泽泥炭腐植酸处于活有机体向成岩转化过程的初始阶段。羧基和酚羟基含量的变化取决于提取腐植酸的泥炭年龄和分解程度,羧酸酸度随泥炭深度和腐殖化程度增加而增大。%Humic substances form most of the organic components of soil, peat and natural waters, and their structure and properties differ very much depending on their source. The aims of this study are to characterize humic acids (HAs) from raised bog peat, to evaluate the homogeneity of peat HAs within peat proifles, and to study peat humiifcation im-pact on properties of HAs. A major impact on the structure of peat HAs have lignin-free raised bog biota (dominantly represented by bryophytes of different origin). On diagenesis scale, peat HAs have an intermediate position between the living organic matter and coal organic matter, and their structure is formed in a process in which more labile structures (carbohydrates, amino acids, etc.) are destroyed, while thermodynamically more stable aromatic and polyaromatic struc-tures emerge as a result of abiotic synthesis. However, in comparison with soil, aquatic and other HAs, aromaticity of peat HAs is much lower. Comparatively, the raised bog peat HAs are at the beginning of the transformation

  16. 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

  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. Origin of lead in eight Central European peat bogs determined from isotope ratios, strengths, and operation times of regional pollution sources.

    Science.gov (United States)

    Novák, Martin; Emmanuel, Simon; Vile, Melanie A; Erel, Yigal; Véron, Alain; Paces, Tomás; Wieder, R Kelman; Vanecek, Mirko; Stepánová, Markéta; Brízová, Eva; Hovorka, Jan

    2003-02-01

    Lead originating from coal burning, gasoline burning, and ore smelting was identified in 210Pb-dated profiles through eight peat bogs distributed over an area of 60,000 km2. The Sphagnum-dominated bogs were located mainly in mountainous regions of the Czech Republic bordering with Germany, Austria, and Poland. Basal peat 14C-dated at 11,000 years BP had a relatively high 206Pb/207Pb ratio (1.193). Peat deposited around 1800 AD had a lower 206Pb/207Pb ratio of 1.168-1.178, indicating that environmental lead in Central Europe had been largely affected by human activity (smelting) even before the beginning of the Industrial Revolution. Five of the sites exhibited a nearly constant 206Pb/207Pb ratio (1.175) throughout the 19th century, resembling the "anthropogenic baseline" described in Northern Europe (1.17). At all sites, the 206Pb/207Pb ratio of peat decreased at least until 1980; at four sites, a reversal to more radiogenic values (higher 206Pb/207Pb), typical of easing pollution, was observed in the following decade (1980-1990). A time series of annual outputs for 14 different mining districts dispersing lead into the environment has been constructed for the past 200 years. The production of Ag-Pb, coal, and leaded gasoline peaked in 1900, 1980, and 1980, respectively. In contrast to other European countries, no peak in annual Pb accumulation rates was found in 1900, the year of maximum ore smelting. The highest annual Pb accumulation rates in peat were consistent with the highest Pb emission rates from coal-fired power plants and traffic (1980). Although maximum coal and gasoline production coincided in time, their isotope ratios were unique. The mean measured 206Pb/207Pb ratios of local coal, ores, and gasoline were 1.19, 1.16, and 1.11, respectively. A considerable proportion of coal emissions, relative to gasoline emisions, was responsible for the higher 206Pb/207Pb ratios in the recent atmosphere (1.15) compared to Western Europe (1.10). As in West European

  19. 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

  20. Tephrostratigraphy and chronology of the Kaipo Lagoon, and 11,000 year old montane peat bog in Urewera National Park, New Zealand

    International Nuclear Information System (INIS)

    Eleven well-preserved Holocene tephras occur interbedded with peat in the Kaipo Lagoon bog in Urewera National Park, North Island. They are identified chiefly by their field appearance, stratigraphy, and ferromagnesian mineralogy. Glass shards from one tephra (Hinemaiaia) were analysed by electron microprobe. The tephras originate from the Taupo, Okataina, and Tongariro Volcanic Centres and, from youngest to oldest, are: Kaharoa Ash, Taupo Pumice, Mapara Tephra, Waimihia Lapilli, Hinemaiaia Tephra, Whakatane Ash, Rotoma Ash, Opepe Tephra, Poronui Tephra, Karapiti Tephra, and Okupata Tephra. Thirteen new radiocarbon ages were obtained on six of the tephras (old T-1/2, years B.P.): Waimihia, 3,250 plus or minus 70 (Wk498), 2,910 plus or minus 60 (Wk499), 3,040 plus or minus 50 (Wk500); Hinemaiaia and Whakatane, 4,490 plus or minus 60 (Wk496), 4,530 plus or minus 60 (Wk497); Whakatane, 4,860 plus or minus 70 (Wk501); Rotoma, 5,440 plus or minus 170 (Wk493), 7,380 plus or minus 80 (Wk494), 7,560 plus or minus 100 (Wk495) (Wk493-495 are all considered anomalously young); Opepe, 8,710 plus or minus 80 (Wk492); Poronui, 10,160 plus or minus 130 (Wk351), 9,960 plus or minus 90 (Wk352), 9,560 plus or minus 80 (Wk491). Estimated ages, assuming constant sedimentation rates, for Karapiti Tephra and Okupata Tephra are 10,100 and 10,300 years, respectively. Two peat horizons below the Okupata Tephra were dated at (old T-1/2) 10,600 plus or minus 90 years B.P. (Wk263) and 11,500 plus or minus 80 years B.P. (Wk264) and date the initial growth of the Kaipo Lagoon bog. Peat accumulation rates have been slow (average 0.19 mm/year) but variable. The identification and dating of the tephras at Kaipo extends their known distribution in eastern North Island, and improves their potential usefulness as isochronous stratigraphic marker units

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

    Science.gov (United States)

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

    2009-10-15

    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. PMID:19683332

  2. Landscape dynamics and fire activity since 6740 cal yr BP in the Cantabrian region (La Molina peat bog, Puente Viesgo, Spain)

    Science.gov (United States)

    Pérez-Obiol, R.; García-Codron, J. C.; Pèlachs, A.; Pérez-Haase, A.; Soriano, J. M.

    2016-03-01

    A lack of paleobotanic studies with adequate resolution and multiproxy approaches has limited proper discussion of vegetation dynamics in Cantabria and of the role of fires in the configuration of the plant landscape during the Holocene in the northwest part of the Iberian peninsula. The pollen diagram of La Molina peat bog in Puente Viesgo (43°15‧38″ N-3°58‧37″ W; ETRS89), located at 484 m.a.s.l., and the study of its sedimentary charcoals allowed the acquisition of a continuous and thorough fire sequence for the last 6700 cal yr BP and an understanding of its relationship to the forest. The results show the importance of human influence on the incidence and characteristics of fire activity during the different phases studied: the Neolithic, Bronze Age, Iron Age, Roman period, and Middle Ages. A synergy seems to exist between dry climate periods (especially during Bond events 3 and 4) and a greater presence of biomass. As the Holocene advances, vegetation coverage clearly tends to decrease. This study provides key elements for understanding the role of fire activity in the forest dynamics of deciduous and evergreen Quercus, Corylus, Pinus, Fagus, and Alnus and demonstrates the strongly artificialized character of the present landscape.

  3. Atmospheric Environmental Changes Records from Peat Bogs: a Review%大气环境变化的泥炭地质档案

    Institute of Scientific and Technical Information of China (English)

    鲍锟山; 赵红梅; 于晓菲; 吕宪国; 王国平

    2011-01-01

    An ombrotrophic peat bog is a domed peatland in which the surface peat layers are hydrologically isolated from the influence of local ground and surface water, and are fed exclusively by atmospheric deposition consisting of both soi1d particles and mineral substances dissolved in rain water. It has proven to be a good continental geochemical archive, and has the unique advantage of a wide global distribution. It preserves intact atmospheric environmental changes' signatures including sea-salt aerosol,soil-dust, acid deposition, heavy metals, and organic pollutants. An efficient method to reconstruct a history of atmospheric environmental variation includes a chronological framework using geological dating techniques followed by biogeochemical analysis of a wide range of proxies. This paper reviews the approaches used to establish depth-age relationships in peat chronologies, and summarizes a large number of informed studies relative to deducing historical influence of ocean, rock-soil and human society on atmosphere. Finally, the slightly insufficient parts as well as the prospect of peat bog archives towards atmospheric variations are put forward.%雨养泥炭沼泽是一种重要的泥炭沼泽类型,具有全球广泛分布的特点,其养分补给主要源于大气降水(包括雨、雪和空气尘埃).它是一个记录大气环境变化的积极的信息储备系统,记录有大气输入的海盐气溶胶、沙尘颗粒、酸沉降、重金属和有机污染物等信息.采用地质定年技术将泥炭深度剖面转化到年代坐标上,并结合泥炭生物地球化学指标检测分析,提取反映这些信息的代用指标,是重建大气环境的变化历史的有效方法.本文讨论了泥炭沉积地球化学行为对沼泽定年和地质记录研究的意义,综述了泥炭沼泽常用的定年方法,总结了大量利用泥炭地质档案反演海洋、岩石-土壤及人类社会对大气环境变化的影响历史的研究,并在此基础上展

  4. Stable (206Pb, 207Pb, 208Pb) and radioactive (210Pb) lead isotopes in 1 year of growth of Sphagnum moss from four ombrotrophic bogs in southern Germany: Geochemical significance and environmental implications

    Science.gov (United States)

    Shotyk, William; Kempter, Heike; Krachler, Michael; Zaccone, Claudio

    2015-08-01

    The surfaces of Sphagnum carpets were marked with plastic mesh and 1 year later the production of plant matter was harvested in four ombrotrophic bogs from two regions of southern Germany: Upper Bavaria (Oberbayern, OB) and the Northern Black Forest (Nordschwarzwald, NBF). Radioactive, 210Pb was determined in solid samples using ultralow background gamma spectrometry while total Pb concentrations and stable isotopes (206Pb, 207Pb, 208Pb) were determined in acid digests using ICP-SMS. Up to 12 samples (40 × 40 cm) were collected per site, and 6-10 sites investigated per bog. The greatest variations within a given sampling site were in the range 212-532 Bq kg-1 for 210Pb activity, whereas 206Pb/207Pb and 208Pb/206Pb varied less than 1%. The median values of all parameters for the sites (6-10 per bog) were not significantly different. The median activities of 210Pb (Bq kg-1) in the mosses collected from the bogs in NBF (HO = 372 ± 56, n = 55; WI = 342 ± 58, n = 93) were slightly less from those in OB (GS = 394 ± 50, n = 55; KL = 425 ± 58, n = 24). However, the mosses in the NBF bogs exhibited much greater productivity (187-202 g m-2 a-1) compared to those of OB (71-91 g m-2 a-1), and this has a profound impact on the accumulation rates of 210Pb (Bq m-2 a-1), with the bogs in the NBF yielding fluxes (HO = 73 ± 30; WI = 65 ± 20) which are twice those of OB (GS = 29 ± 11; KL = 40 ± 13). Using the air concentrations of 210Pb measured at Schauinsland (SIL) in the southern Black Forest and average annual precipitation, the atmospheric fluxes of 210Pb at SIL (340 Bq m-2 a-1) exceeds the corresponding values obtained from the mosses by a factor of five, providing the first quantitative estimate of the net retention efficiency of 210Pb by Sphagnum. When the 210Pb activities of all moss samples are combined (n = 227), a significant decrease with increasing plant production rate is observed; in contrast, total Pb concentrations show the opposite trend. The contrasting

  5. Testing a new version of the DigiBog model to explore the differential response of peatland microforms to shifts in surface wetness

    Science.gov (United States)

    Garneau, Michelle; Baird, Andrew J.; Morris, Paul J.; van Bellen, Simon

    2016-04-01

    Over the last decades, many hypotheses have been put forward to explain pool formation in northern peatlands including topographic, biotic or climatic factors. Several studies suggest that pool formation is primarily controlled by autogenic, edaphic and topographic factors rather than external climatic influences (allogenic factors). However, there is still no consensus to explain pool formation and to confirm whether their initiation is primarily associated with autogenic or allogenic processes. Subarctic fens in northeastern Canada are characterized by a patterned surface of pools, flarks and narrow strings. Due to their geographic location at the northern ombrotrophic peatland distribution, these poor fens have been highly sensitive to hydroclimatic variations that influenced pool development and expansion. Our data indicate that wet hollows or shallow pools developed at minimal ages between ca 4200 cal BP and ca 2500 cal BP. We hypothesize that pool developed as secondary features under wetter and cooler conditions that (i) caused shorter growing seasons which negatively impacted on peat accumulation and (ii) led to lower rates of evaporation, and that (i) and (ii) in combination led to increased surface wetness. The differential response of microforms to shifts in surface wetness show the complexity of processes involved in pool initiation. A recent version of the DigiBog model (Morris et al, 2015), that allows for sub-seasonal variations in precipitation and evaporation, is used to explore the interactions between climate, growing season, peat productivity, peat hydraulic properties and water-table behaviour. Model results suggest that decreases in growing season length, combined with decreases in evapotranspiration, can explain long-lived shifts to wetter conditions in peatlands. If evapotranspiration is reduced but growing season does not vary, long-lived shifts in peatland wetness are less likely and the peatland instead tends to show a homeostatic

  6. A 15 000-year record of climate change in northern New Mexico, USA, inferred from isotopic and elemental contents of bog sediments

    Science.gov (United States)

    Cisneros-Dozal, L. M.; Heikoop, J.M.; Fessenden, J.; Anderson, R. Scott; Meyers, P.A.; Allen, C.D.; Hess, M.; Larson, T.; Perkins, G.; Rearick, M.

    2010-01-01

    Elemental (C, N, Pb) and isotopic (??13C, ??15N) measurements of cored sediment from a small bog in northern New Mexico reveal changes in climate during the Late Pleistocene and Holocene. Abrupt increases in Pb concentration and ??13C values ca. 14 420 cal. YBP indicate significant runoff to the shallow lake that existed at that time. Weathering and transport of local volcanic rocks resulted in the delivery of Pb-bearing minerals to the basin, while a 13C-enriched terrestrial vegetation source increased the ??13C values of the sedimentary material. Wet conditions developed over a 300 a period and lasted for a few hundred years. The Younger Dryas period (ca. 12 700-11 500 cal. YBP) caused a reduction in terrestrial productivity reflected in decreasing C/N values, ??15N values consistently greater than 0??? and low organic content. By contrast, aquatic productivity increased during the second half of this period, evidenced by increasing ??13C values at the time of highest abundance of algae. Dry conditions ca. 8 000-6 000 cal. YBP were characterised by low organic carbon content and high Pb concentrations, the latter suggesting enhanced erosion and aeolian transport of volcanic rock. The range in ??13C, ??15N and C/N values in the sedimentary record fall within the range of modern plants, except during the periods of runoff and drought. The sedimentary record provides evidence of natural climate variability in northern New Mexico, including short- (multi-centennial) and long-(millennial) term episodes during the Late Pleistocene and Holocene. Copyright ?? 2010 John Wiley & Sons, Ltd.

  7. High soil solution carbon und nitrogen concentrations in a drained Atlantic bog are reduced to natural levels by 10 yr of rewetting

    Directory of Open Access Journals (Sweden)

    S. Frank

    2013-10-01

    Full Text Available Artificial drainage of peatlands causes dramatic changes in the release of greenhouse gases and in the export of dissolved carbon (C and nutrients to downstream ecosystems. Rewetting anthropogenically altered 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 yr and 4 month, respectively. The peeper technique was used to receive a high vertical sampling resolution. Within one Atlantic bog complex a near natural site, two drained grasslands sites with different mean water table positions, and a former peat cutting area rewetted 10 yr ago were chosen. Our results clearly indicate that drainage increased the concentration of dissolved organic carbon (DOC, ammonia, nitrate and dissolved organic nitrogen (DON compared to the near natural site. Drainage depth further determined the release and therefore the concentration level of DOC and N species, but the biochemical cycling and therefore dissolved organic matter (DOM quality and N species composition were unaffected. Thus, especially deep drainage can cause high DOC losses. In general, DOM at drained sites was enriched in aromatic moieties as indicated by SUVA280 and showed a higher degradation status (lower DOC to DON ratio compared to the near natural site. At the drained sites, equal C to N ratios of uppermost peat layer and DOC to DON ratio of DOM in soil solution suggest that the uppermost degraded peat layer is the main source of DOM. Nearly constant DOC to DON ratios and SUVA280 values with depth furthermore indicated that DOM moving downwards through the drained sites remained largely unchanged. DON and ammonia contributed most to the total dissolved nitrogen (TN. The subsoil concentrations of nitrate were negligible due to strong decline in nitrate around mean water table depth. Methane production during the winter months at

  8. High soil solution carbon und nitrogen concentrations in a drained Atlantic bog are reduced to natural levels by 10 yr of rewetting

    Science.gov (United States)

    Frank, S.; Tiemeyer, B.; Gelbrecht, J.; Freibauer, A.

    2013-10-01

    Artificial drainage of peatlands causes dramatic changes in the release of greenhouse gases and in the export of dissolved carbon (C) and nutrients to downstream ecosystems. Rewetting anthropogenically altered 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 yr and 4 month, respectively. The peeper technique was used to receive a high vertical sampling resolution. Within one Atlantic bog complex a near natural site, two drained grasslands sites with different mean water table positions, and a former peat cutting area rewetted 10 yr ago were chosen. Our results clearly indicate that drainage increased the concentration of dissolved organic carbon (DOC), ammonia, nitrate and dissolved organic nitrogen (DON) compared to the near natural site. Drainage depth further determined the release and therefore the concentration level of DOC and N species, but the biochemical cycling and therefore dissolved organic matter (DOM) quality and N species composition were unaffected. Thus, especially deep drainage can cause high DOC losses. In general, DOM at drained sites was enriched in aromatic moieties as indicated by SUVA280 and showed a higher degradation status (lower DOC to DON ratio) compared to the near natural site. At the drained sites, equal C to N ratios of uppermost peat layer and DOC to DON ratio of DOM in soil solution suggest that the uppermost degraded peat layer is the main source of DOM. Nearly constant DOC to DON ratios and SUVA280 values with depth furthermore indicated that DOM moving downwards through the drained sites remained largely unchanged. DON and ammonia contributed most to the total dissolved nitrogen (TN). The subsoil concentrations of nitrate were negligible due to strong decline in nitrate around mean water table depth. Methane production during the winter months at the drained

  9. 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

  10. 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...

  11. 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

  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. Rare earth element and Nd isotope geochemistry of an ombrotrophic peat bog at Karukinka (Chile, 53.9° S): a palaeo-record of Holocene dust deposition in Tierra del Fuego.

    Science.gov (United States)

    Vanneste, Heleen; De Vleeschouwer, François; Vanderstraeten, Aubry; Mattielli, Nadine; Triquet, Delphine; Piotrowska, Natalia; Le Roux, Gael

    2013-04-01

    The value of ombrotrophic peat bogs as past atmospheric dust records, has been increasingly recognized over the past 10 years. Their high accumulation rates provide high resolution archives of natural atmospheric dust deposition since the Late Glacial, often missing in marine, lake and ice core records. Consequently, peat deposits can be used as a proxy for atmospheric circulation patterns and thus palaeoclimate. In the Southern Hemisphere, the climate is considered to be driven by the Southern Westerly Wind belt (SSW), as it significantly affects the Antarctic Circumpolar Current and hence atmospheric CO2 levels. Palaeo SSW belt migrations have been observed in palaeoclimate records but, reconstructions of SSW shifts and associated climatic changes are incoherent, in particular for the Holocene. As peatlands thrive in southwest Tierra del Fuego due to its high annual precipitation, a remote ombrotrophic peat bog at Karukinka (southwest on the Isla Grande de Tierra del Fuego) was sampled, to investigate the Holocene palaeoclimate in southern South America based on dust deposition records. A 4,5 m long Russian D-core was recovered and subsequently subsampled for elemental and isotope geochemistry in addition to density and radiocarbon dating measurements. Initial results show a number of layers enriched in scandium, indicating the presence of lithogenic material, i.e. dust. Rare earth element patterns indicate at least 2 different sources. The most significant dust peak occurs at the base of the core at ~7300 Cal years B.P and has a neodymium isotopic composition of 2.2, suggesting a volcanic origin.

  14. The prospects for the survival of the population of a boreal relict species, Betula humilis Schrk., in a small isolated peat bog in the Łęczna - Włodawa Lakeland

    Directory of Open Access Journals (Sweden)

    Magdalena Pogorzelec

    2012-12-01

    Full Text Available An attempt was made to identify the major risks to the population of Betula humilis Schrk. existing in a small isolated transitional peat bog near Lake Bikcze, in the Łęczna-Włodawa Lakeland. The biometric features of 40 Betula humilis individuals were measured as well as the growth of shoots, flowering and fruiting were observed. Habitat conditions were characterized by making measurements of selected abiotic and biocenotic environmental factors. The obtained results allowed us to identify two main threats to the proper functioning of the study population. The first one is the possible loss of genetic identity of the species as a result of probable ongoing introgression by the potential crossing of Betula humilis with other species of the genus Betula, which are numerous in the flora of the studied area. Another threat is a change in habitat conditions (mainly light and water conditions, which is due to the accelerated secondary succession manifested by the expansion of common species such as Salix cinerea, Betula pendula, and Phragmites australis.

  15. Fate of N in a peatland, Whim bog: N immobilisation in the vegetation and peat, leakage into pore water and losses as N2O depend on the form of N

    Directory of Open Access Journals (Sweden)

    C. Field

    2012-07-01

    Full Text Available Peatlands' vast carbon reserves accumulated under low nitrogen availability. Carbon and nitrogen cycling are inextricably linked, so what are the consequences of increased reactive nitrogen deposition for the sustainability and functioning of peatlands, and does the form of the nitrogen deposition make a difference? We have addressed these questions for an ombrotrophic peatland, Whim bog in SE Scotland, using a globally unique field simulation of reactive N deposition as dry deposited ammonia and wet deposited reduced N, ammonium and oxidised N, nitrate, added as ammonium chloride or sodium nitrate. The effects of 10 yr of reactive N additions, 56 kg N ha−1 yr−1, depended on the N form. Ammonia-N deposition caused the keystone Sphagnum species, together with the main shrub Calluna and the pleurocarpous mosses to disappear, exposing up to 30% of the peat surface. This led to a significant increase in soil water nitrate and nitrous oxide emissions. By contrast wet deposited N, despite significantly reducing the cover of Sphagnum and Pleurozium moss, did not have a detrimental effect on Calluna cover nor did it significantly change soil water N concentrations or nitrous oxide emissions. Importantly 10 yr of wet deposited N did not bare the peat surface nor significantly disrupt the vegetation, enabling the N to be retained within the carbon rich peatland ecosystems. However, given the significant role of Sphagnum in maintaining conditions that retard decomposition this study suggests that all nitrogen forms will eventually compromise carbon sequestration by peatlands through loss of some keystone Sphagnum species.

  16. Fate of N in a peatland, Whim bog: immobilisation in the vegetation and peat, leakage into pore water and losses as N2O depend on the form of N

    Directory of Open Access Journals (Sweden)

    P. Levy

    2013-01-01

    Full Text Available Peatlands represent a vast carbon reserve that has accumulated under conditions of low nitrogen availability. Given the strong coupling between the carbon and nitrogen cycles, we need to establish the consequences of the increase in reactive nitrogen deposition for the sustainability of peatlands, and whether the form in which the nitrogen is deposited makes a difference. We have addressed these questions using a globally unique field simulation of reactive N deposition as dry deposited ammonia and wet deposited reduced N, ammonium and oxidised N, nitrate, added as ammonium chloride or sodium nitrate, to an ombrotrophic peatland, Whim bog in SE Scotland. Here we report the fate of 56 kg N ha−1 yr−1 additions over 10 yr and the consequences. The effects of 10 yr of reactive N additions depended on the form in which the N was applied. Ammonia-N deposition caused the keystone Sphagnum species, together with the main shrub Calluna and the pleurocarpous mosses, to disappear, exposing up to 30% of the peat surface. This led to a significant increase in soil water nitrate and nitrous oxide emissions. By contrast wet deposited N, despite significantly reducing the cover of Sphagnum and Pleurozium moss, did not have a detrimental effect on Calluna cover nor did it significantly change soil water N concentrations or nitrous oxide emissions. Importantly 10 yr of wet deposited N did not bare the peat surface nor significantly disrupt the vegetation enabling the N to be retained within the carbon rich peatland ecosystems. However, given the significant role of Sphagnum in maintaining conditions that retard decomposition, this study suggests that all nitrogen forms will eventually compromise carbon sequestration by peatlands through loss of some keystone Sphagnum species.

  17. 雨养沼泽泥炭腐殖化过程中的腐植酸性质成因与变化研究%Formation and Changes of Humic Acid Properties during Peat Humiifcation Process within Ombrotrophic Bogs

    Institute of Scientific and Technical Information of China (English)

    Oskars Purmalis(著); Maris Klavins(著); 任忠秀(译); 包雪梅(译); 于家伊(译)

    2013-01-01

      研究生命有机物质的腐殖化过程是了解碳的生物化学循环所必不可少的。本研究的主要目的是分析泥炭性质、泥炭腐植酸与泥炭腐殖化度三者之间的关系。对两个雨养泥炭沼泽的泥炭剖面各层中提取的腐植酸样品进行了分析,并对泥炭年龄、分解度、腐殖化度、植物构成、泥炭腐植酸性质(元素和有效成分)进行了研究。结果发现,泥炭腐植酸的组成受造炭生命有机物质前体的组成影响较小,对造炭生物性质多样性的研究要比对泥炭性质多样性的研究更有意义,由此可以揭示腐殖化过程对泥炭性质的主导性作用。%Studies of the living organic matter humiifcation process are essential for understanding the carbon biogeo-chemical cycle. The aim of this study is to analyze relations between the properties of peat, peat humic acids and peat humiifcation degree. The analysis has been done on samples of humic substances extracted from peat proifles in two ombrotrophic bogs and relations between peat age, decomposition and humiifcation degree, botanical composition and properties of peat humic acids (elemental, functional composition) were studied. The found variability of peat properties is less signiifcant than differences in the properties of peat-forming living matter, thus revealing the dominant impact of humiifcation process on the properties of peat. Correspondingly, composition of peat humic acids is little affected by differ-ences in the composition of precursor living organic material.

  18. Research on the energy saving technology of BOG compressor of Jiangsu LNG Receiving Terminal%江苏LNG接收站BOG压缩机的节能降耗措施

    Institute of Scientific and Technical Information of China (English)

    段碧君

    2012-01-01

    介绍了LNG接收站工艺流程,阐述了活塞式压缩机的工作原理与技术特点,给出了各能耗参数的计算方法,包括排气量、供气量、容积系数、排气压力与级数、压缩比、排气温度、功率、效率等.分析了LNG接收站BOG压缩机的能耗问题,确定了能耗的主要影响因素,包括进气温度、进气压力、气相介质携液率、压缩比以及驱动电机的性能.基于此,提出了节能降耗措施:降低进气温度、控制进气压力、降低气相携液率、将电机改造为变频电机、在电动机拖动系统中加装功率因数控制器、经常更换冷却水系统的冷却液.%This article introduces the process flow of LNG receiving terminal, and also elaborates the working principle and technical characteristics of piston compressors. It also gives the calculating method of the energy consumption parameters, including the exhaust gas volume, the volume coefficient, discharge pressure and progression, the compression ratio, exhaust temperature, power, efficiency, and so on. It identifies the main factors of energy consumption of LNG receiving terminal BOG compressor, including the intake air temperature, inlet pressure, compression ratio and the drive motor performance. So, the energy saving measures are as follows, that is, reducing intake air temperature, controlling the inlet pressure, reducing the gas medium carrying liquid ratio, transforming the motor to frequency conversion motor, installing power factor controllers, regularly replacing of the cooling water coolant system.

  19. Morphogenetic Litter Types of Bog Spruce Forests

    OpenAIRE

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

    2015-01-01

    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, w...

  20. Ny bog: Den farvede franske general

    DEFF Research Database (Denmark)

    Østergaard, Uffe

    2013-01-01

    Anmeldelse af: Tom Reiss: 'Den sorte greve. Napoleons rival og den virkelige greve af Monte Cristo', Informations Forlag, 517 s.......Anmeldelse af: Tom Reiss: 'Den sorte greve. Napoleons rival og den virkelige greve af Monte Cristo', Informations Forlag, 517 s....

  1. Zmierzch bogów w Dubrowniku

    OpenAIRE

    Pająk, Patrycjusz

    2013-01-01

    The Croatian film Occupation in 26 pictures(1978), directed by Lordan Zafranovićis considered as one of the most controversial vision of the Second World War in Yugoslav cinema. The director uses the ornamental style, modeled on Italian cinema, to portray the change of power in Dubrovnik in 1941 – at the beginning of the fascist occupation of the city. He juxtaposes the licentiousness of Italian, German and Croatian fascists and the fall of the Dub...

  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. 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

  4. 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.

  5. Emissions of biogenic sulfur gases from northern bogs and fens

    Science.gov (United States)

    Demello, William Zamboni; Hines, Mark E.; Bayley, Suzanne E.

    1992-01-01

    Sulfur gases are important components of the global cycle of S. They contribute to the acidity of precipitation and they influence global radiation balance and climate. The role of terrestrial sources of biogenic S and their effect on atmospheric chemistry remain as major unanswered questions in our understanding of the natural S cycle. The role of northern wetlands as sources and sinks of gaseous S by measuring rates of S gas exchange as a function of season, hydrologic conditions, and gradients in tropic status was investigated. Experiments were conducted in wetlands in New Hampshire, particularly a poor fen, and in Mire 239, a poor fen at the Experimental Lakes Area (ELA) in Ontario. Emissions were determined using Teflon enclosures, gas cryotrapping methods and gas chromatography (GC) with flame photometric detection. Dynamic (sweep flow) and static enclosures were employed which yielded similar results. Dissolved S gases and methane were determined by gas stripping followed by GC.

  6. Bog s ljudmi prebõvajet / Igor Gromov

    Index Scriptorium Estoniae

    Gromov, Igor

    1999-01-01

    Laste joonistuste ja kaasaegse ikoonimaali näitusest Tallinna Vene Draamateatri galeriis. Ikoonide tekkest ja tähendusest kunstnik Leonid Sokolovi abiga, kelle töid eksponeeritakse ka sellel näitusel

  7. Degradation of Parathion by Microorganisms from Cranberry Bogs

    International Nuclear Information System (INIS)

    Full text: Oxygen concentration and different carbon sources drastically altered parathion degradation in culture media inoculated with microorganisms from Wisconsin cranberry (Vaccinium macrocarpon Ait.) growing soils. These microorganisms also grew in basal salts media utilizing parathion as a sole carbon source. 14CO2 was produced only from phenyl-labelled parathion while 14C-(ethyl)-parathion derived radiocarbon remained in the stale media of the soil-free cultures. Addition of 0.05% glucose to basal salts medium inhibited 14C-(phenyl)-parathion degradation while the addition of 0.05% yeast extract to basal salts medium also inhibited microbiological degradation of the insecticide to 14CO2, but to a lesser extent. Aminoparathion and aminoparaoxon were formed only in basal salts medium with 0.05% yeast extract. Aerobic cultures produced more 14CO2 from 14C-(phenyl)-parathion and less aminoparathion than anaerobic cultures. Aminoparathion was more abundant in cultures with inocula obtained from the 18- to 23-cm layer than with culture inocula obtained from the 0- to 5-cm soil layer under both aerobic and anaerobic conditions. (author)

  8. Carbon balance of a drained forested bog in southern Finland

    Science.gov (United States)

    Minkkinen, Kari; Penttilä, Timo; Ojanen, Paavo; Lohila, Annalea

    2016-04-01

    Carbon and greenhouse gas (GHG) dynamics of a drained forested peatland in southern Finland were measured over multiple years, including one with severe drought during growing season. Net ecosystem carbon dioxide exchange (NEE) was measured with an eddy covariance method from a tower above the forest. Soil and forest floor CO2, CH4 and N2O fluxes were measured from the strips and from ditches with closed chambers. Biomasses and litter production were sampled, and soil subsidence was measured by consequtive levelings of the peat surface. The data were used to estimate the ecosystem C pools and annual fluxes of carbon and GHGs of the peatland and to analyse the impact of periodical drought on the carbon fluxes. The drained peatland was a strong sink of carbon dioxide in all studied years. Soil CO2 balance was estimated by subtracting the carbon sink of the growing tree stand from NEE, and it showed that also the soil was a sink of carbon in all studied years. A drought period in one summer significantly decreased the sink through decreased GPP. Drought also decreased the ecosystem respiration, including soil respiration. Decreasing water table thus did not increase, but rather decreased CO2 efflux from the peat soil. The site was a small sink for CH4, even when emissions from ditches were included. N2O emissions were small from all surfaces. Despite of the continuous carbon sink, peat surface subsided slightly (1.4 mm a-1) during the 10-year measurement period, which is interpreted to mean mainly compaction, rather than oxidation of the peat. It is concluded that this drained peatland acts as a continuous soil C sink similarly to an undrained peatland. The reason may be the relatively small water-level drawdown compared to an undrained situation, the consequently rather small changes in plant community structure and the significantly improved tree stand growth and litter production. The consequences of continuing production forestry vs. restoration of the site on the GHG fluxes and climate impact will be discussed.

  9. Root growth of tomato seedlings intensified by humic substances from peat bogs

    Directory of Open Access Journals (Sweden)

    Alexandre Christofaro Silva

    2011-10-01

    Full Text Available Peats are an important reserve of humified carbon in terrestrial ecosystems. The interest in the use of humic substances as plant growth promoters is continuously increasing. The objective of this study was to evaluate the bioactivity of alkaline soluble humic substances (HS, humic (HA and fulvic acids (FA isolated from peats with different decomposition stages of organic matter (sapric, fibric and hemic in the Serra do Espinhaço Meridional, state of Minas Gerais. Dose-response curves were established for the number of lateral roots growing from the main plant axis of tomato seedlings. The bioactivity of HA was greatest (highest response in lateral roots at lowest concentration while FA did not intensify root growth. Both HS and HA stimulated root hair formation. At low concentrations, HS and HA induced root hair formation near the root cap, a typical hormonal imbalance effect in plants. Transgenic tomato with reporter gene DR5::GUS allowed the observation that the auxin-related signalling pathway was involved in root growth promotion by HA.

  10. Organochlorine pesticide residues in inactive cranberry bogs of the Edwin B. Forsythe National Wildlife Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — A 1996 Baseline Contaminants Investigation of the U.S. Fish & Wildlife Service’s (Service) Edwin B. Forsythe National Wildlife Refuge (EBFNWR) revealed elevated...

  11. Ecology of some mire and bog plant communities in the Western Italian Alps

    Directory of Open Access Journals (Sweden)

    Giorgio BUFFA

    2003-02-01

    Full Text Available During a mire vegetation study, conducted mainly in the subalpine-alpine sector of the Western Italian Alps, the ecology of several plant communities and numerous moss species of this kind of vegetation was evaluated. The study area covered the Piedmontese sector of the Graian Alps, the eastern sector of the Aosta Valley as well as certain localities of the Pennine Alps, the Canavese district and the Maritime Alps. They have a rocky substratum representative of the various regional lithologies and include the main sectors characterised by the highest precipitation. Three hundred and twenty two relevées were made using the phytosociological method and the pH and the conductivity of the water table and its depth were measured directly. Cluster Analysis allowed a classification of the samples and the identification of various groups of plant communities. Ordination performed by DCA and CCA allowed us to identify the ecological features of the various plant communities by using the values of the main environmental parameters, measured directly in the field, and certain climatic parameters (altitude and mean annual precipitation available. The use of climatic parameters is an important result for identifying communities which show greater oceanicity, something that is underlined also by the presence of indicator species such as Sphagnum papillosum and S. subnitens. Furthermore the communities are arranged in a "poor-rich" gradient, and are also profoundly influenced by depth to water table which is inversely correlated to the pH. Therefore we find certain kinds of communities all with a very low water table and which are little affected by its chemistry. Other groups share the fact that the water table is outcropping or near the surface and are distinguishable for their pH values and conductivity. We discuss the different response of the bryophytes and vascular plants of these communities to the environmental parameters considered, in light of their anatomic and functional differences. Bryophytes are more sensitive to environmental and climatic parameters whilst vascular plants are mostly ubiquitous in the relevées with a greater ecological plasticity.

  12. Changes in vegetation since the late glacial on peat bog in the Small Carpathians

    International Nuclear Information System (INIS)

    Mires are ecosystems accumulating high amount of organic matter with preserved micro- and macro-fossils. Thus they can serve as natural archives allowing reconstruction of local vegetation and landscape development. Main aim of this study was to bring evidence of the whole Holocene history of mire birch woodland located on the ridge of the Male Karpaty Mts (SW Slovakia) using pollen analysis. One peat core was sampled from the middle part containing the whole Holocene sequence. The local development of study site started with small lake in a terrain depression, which arose at the end of the Late Glacial (Middle Dryas). The Late Glacial landscape was mosaic of birch-pine forests on suitable places and Artemisia steppes. Early Holocene is characterized by steep decline of pine and increase of Corylus and other mesophilous trees (Quercus, Tilia, Ulmus, Fraxinus). Fagus started dominate in middle Holocene (about 5000 cal BP). The recent vegetation established only several hundred years ago (ca 500 cal. BP), when birch started dominate. (author)

  13. Gene flow rise with habitat fragmentation in the bog fritillary butterfly (Lepidoptera: Nymphalidae

    Directory of Open Access Journals (Sweden)

    Descimon Henri

    2008-03-01

    Full Text Available Abstract Background The main components of the spatial genetic structure of the populations are neighbourhood size and isolation by distance. These may be inferred from the allele frequencies across a series of populations within a region. Here, the spatial population structure of Proclossiana eunomia was investigated in two mountainous areas of southern Europe (Asturias, Spain and Pyrenees, France and in two areas of intermediate elevation (Morvan, France and Ardennes, Belgium. Results A total of eight polymorphic loci were scored by allozyme electrophoresis, revealing a higher polymorphism in the populations of southern Europe than in those of central Europe. Isolation by distance effect was much stronger in the two mountain ranges (Pyrenees and Asturias than in the two areas of lower elevation (Ardennes and Morvan. By contrast, the neighbourhood size estimates were smaller in the Ardennes and in the Morvan than in the two high mountain areas, indicating more common movements between neighbouring patches in the mountains than in plains. Conclusion Short and long dispersal events are two phenomena with distinct consequences in the population genetics of natural populations. The differences in level of population differentiation within each the four regions may be explained by change in dispersal in lowland recently fragmented landscapes: on average, butterflies disperse to a shorter distance but the few ones which disperse long distance do so more efficiently. Habitat fragmentation has evolutionary consequences exceeding by far the selection of dispersal related traits: the balance between local specialisation and gene flow would be perturbed, which would modify the extent to which populations are adapted to heterogeneous environments.

  14. Snow cover manipulation effects on microbial community structure and soil chemistry in a mountain bog

    NARCIS (Netherlands)

    Robroek, B.J.M.; Heijboer, A.; Jassey, V.E.J.; Hefting, M.M.; Rouwenhorst, T.G.; Buttler, A.; Bragazza, L.

    2013-01-01

    Background and Aims Alterations in snow cover driven by climate change may impact ecosystem functioning, including biogeochemistry and soil (microbial) processes. We elucidated the effects of snow cover manipulation (SCM) on above-and belowground processes in a temperate peatland. Methods In a Swiss

  15. Impact of long-term wetting on belowground respiration and methanogenesis in Luther Bog, Ontario

    Science.gov (United States)

    Goebel, Marie; Blodau, Christian

    2016-04-01

    Peatlands play a major role in the global carbon cycle. They store one-third of total world soil carbon, sequester carbon dioxide (CO2) and release CO2 and methane (CH4). Climate and land-use change are predicted to cause either wetter winters and wetter summers or wetter winters and drier summers in the area where northern peatlands are located. Feedback on processes in the peat is poorly understood on the time scale of decades. In this study, we investigated impacts of long-term wetting and long-term fluctuating water table on potential CO2 and CH4 production rates and organic matter quality of the fractions bulk peat, pore water and leachate. Bulk peat potential CO2 production rates of 2.38 to 25.55 μmol g-1 d-1 (aerobic) and 1.53 to 7.33 μmol g-1 d-1 (anaerobic) decreased with depth along with a decrease in organic matter quality. Potential CH4 production rates (0.002 to 2.60 μmol g-1 d-1) increased with anaerobic conditions and a lack of electron acceptors rather than being dependent on the availability of labile organic matter. This pattern was less evident in solute fraction samples where labile compounds in top layers were probably either too labile to be detected or water movement obscured differences between depths. Bulk peat potential anaerobic CO2 and CH4 production increased through long-term wetting. As wetting did not change organic matter quality or aerobic production rates, increased anaerobic production rates likely originate from microorganisms adapted to anaerobic conditions. All indicators of organic matter quality, FTIR ratios, SUVA254, E2:E3, HIX, FI and PARAFAC, provided similar results. Other than expected, wetting did not result in higher organic matter quality in bulk peat and leachate. Drier conditions in summer led to reduced organic matter quality. In pore water, long-term wetter conditions resulted in a higher organic matter quality. Slow-down of decomposition due to anaerobic conditions is unlikely, as this was not the case with respect to the other fractions. Mixing with groundwater could have transported organic matter of high quality to the wetted site. Potential CO2 production rates were not affected by long-term water table change. Organic matter quality of the wetted site may have been also overestimated in our study as vegetation change may have changed litter and peat quality as well. This study revealed that long-term wetting probably does not change organic matter quality as decisively as expected. Potential anaerobic CO2 and CH4 production rates rather increased as long as conditions were more constantly anoxic. Long-term lowered or fluctuating water table could potentially result in smaller future emissions due to a reduced organic matter quality, but also to less carbon sequestration.

  16. Impact of long-term wetting on belowground respiration and methanogenesis in Luther Bog, Ontario

    Science.gov (United States)

    Goebel, Marie; Blodau, Christian

    2016-04-01

    Peatlands play a major role in the global carbon cycle. They store one-third of total world soil carbon, sequester carbon dioxide (CO2) and release CO2 and methane (CH4). Climate and land-use change are predicted to cause either wetter winters and wetter summers or wetter winters and drier summers in the area where northern peatlands are located. Feedback on processes in the peat is poorly understood on the time scale of decades. In this study, we investigated impacts of long-term wetting and long-term fluctuating water table on potential CO2 and CH4 production rates and organic matter quality of the fractions bulk peat, pore water and leachate. Bulk peat potential CO2 production rates of 2.38 to 25.55 μmol g‑1 d‑1 (aerobic) and 1.53 to 7.33 μmol g‑1 d‑1 (anaerobic) decreased with depth along with a decrease in organic matter quality. Potential CH4 production rates (0.002 to 2.60 μmol g‑1 d‑1) increased with anaerobic conditions and a lack of electron acceptors rather than being dependent on the availability of labile organic matter. This pattern was less evident in solute fraction samples where labile compounds in top layers were probably either too labile to be detected or water movement obscured differences between depths. Bulk peat potential anaerobic CO2 and CH4 production increased through long-term wetting. As wetting did not change organic matter quality or aerobic production rates, increased anaerobic production rates likely originate from microorganisms adapted to anaerobic conditions. All indicators of organic matter quality, FTIR ratios, SUVA254, E2:E3, HIX, FI and PARAFAC, provided similar results. Other than expected, wetting did not result in higher organic matter quality in bulk peat and leachate. Drier conditions in summer led to reduced organic matter quality. In pore water, long-term wetter conditions resulted in a higher organic matter quality. Slow-down of decomposition due to anaerobic conditions is unlikely, as this was not the case with respect to the other fractions. Mixing with groundwater could have transported organic matter of high quality to the wetted site. Potential CO2 production rates were not affected by long-term water table change. Organic matter quality of the wetted site may have been also overestimated in our study as vegetation change may have changed litter and peat quality as well. This study revealed that long-term wetting probably does not change organic matter quality as decisively as expected. Potential anaerobic CO2 and CH4 production rates rather increased as long as conditions were more constantly anoxic. Long-term lowered or fluctuating water table could potentially result in smaller future emissions due to a reduced organic matter quality, but also to less carbon sequestration.

  17. Skarp og præcis bog om præstationsløn

    DEFF Research Database (Denmark)

    Bukh, Per Nikolaj

    2010-01-01

    Anmeldelse af Rewarding Performance: Guiding principles, custom strategies, Robert J. Greene, Routledge......Anmeldelse af Rewarding Performance: Guiding principles, custom strategies, Robert J. Greene, Routledge...

  18. Spatial ecology of peatland ecosystems: Spatial self-organization and catastrophic shifts in bogs

    NARCIS (Netherlands)

    Eppinga, M.B.

    2004-01-01

    Positive feedback interactions, as between plants and their abiotic environment, may have the consequence that an ecosystem has alternate stable equilibrium states. As a result, a gradual change in environmental conditions may lead to discontinuous, catastrophic shifts in such ecosystems. Until now,

  19. Biometrical study of some individuals chosen from Pinus mugo turra populations in the peat bog "Bór na Czerwonem"

    OpenAIRE

    Alina Bączkiewicz

    2014-01-01

    Sixteen individuals were sampled for study of variation in 17 anatomical and morphological characters. Only individuals of low polycormic growth (trait typical for Pinus mugo Turra) connected with incurved one-year-cone stipes (a similar situation exists in Pinus sylvestris L.) were chosen, thus the sample studied cannot be treated as a random one. It has been shown by multivariate statistical analysis that these 16 individuals are quite different from each other, Mahalanobis'generalized dist...

  20. Alpha- and Gammaproteobacterial Methanotrophs Codominate the Active Methane-Oxidizing Communities in an Acidic Boreal Peat Bog

    OpenAIRE

    Esson, Kaitlin C.; Lin, Xueju; Kumaresan, Deepak; Jeffrey P Chanton; Murrell, J. Colin; Kostka, Joel E.

    2016-01-01

    The objective of this study was to characterize metabolically active, aerobic methanotrophs in an ombrotrophic peatland in the Marcell Experimental Forest, Minnesota, USA. Methanotrophs were investigated in the field and in laboratory incubations using DNA-stable isotope probing, expression studies on particulate methane monooxygenase (pmoA) genes, and amplicon sequencing of 16S rRNA genes. Potential rates of oxidation ranged from 14-17 μmol CH4 g dry wt soil-1 d-1. Within DNA-SIP incubations...

  1. Alpha- and Gammaproteobacterial Methanotrophs Codominate the Active Methane-Oxidizing Communities in an Acidic Boreal Peat Bog.

    Science.gov (United States)

    Esson, Kaitlin C; Lin, Xueju; Kumaresan, Deepak; Chanton, Jeffrey P; Murrell, J Colin; Kostka, Joel E

    2016-04-15

    The objective of this study was to characterize metabolically active, aerobic methanotrophs in an ombrotrophic peatland in the Marcell Experimental Forest, in Minnesota. Methanotrophs were investigated in the field and in laboratory incubations using DNA-stable isotope probing (SIP), expression studies on particulate methane monooxygenase (pmoA) genes, and amplicon sequencing of 16S rRNA genes. Potential rates of oxidation ranged from 14 to 17 μmol of CH4g dry weight soil(-1)day(-1) Within DNA-SIP incubations, the relative abundance of methanotrophs increased from 4%in situto 25 to 36% after 8 to 14 days. Phylogenetic analysis of the(13)C-enriched DNA fractions revealed that the active methanotrophs were dominated by the generaMethylocystis(type II;Alphaproteobacteria),Methylomonas, andMethylovulum(both, type I;Gammaproteobacteria). In field samples, a transcript-to-gene ratio of 1 to 2 was observed forpmoAin surface peat layers, which attenuated rapidly with depth, indicating that the highest methane consumption was associated with a depth of 0 to 10 cm. Metagenomes and sequencing of cDNApmoAamplicons from field samples confirmed that the dominant active methanotrophs wereMethylocystisandMethylomonas Although type II methanotrophs have long been shown to mediate methane consumption in peatlands, our results indicate that members of the generaMethylomonasandMethylovulum(type I) can significantly contribute to aerobic methane oxidation in these ecosystems. PMID:26873322

  2. Starting out - What do you do when a trip to the loo is anything but bog standard?

    Science.gov (United States)

    Phillips, Holly Morgan

    2016-05-18

    During my nurse training, I was in a lecture, listening to a woman describing the problems she and her son experienced using the loo in outpatients. Her son had profound multiple learning disabilities, and what should have been a simple matter of gaining access to a toilet became a physical, and emotional, struggle. PMID:27191437

  3. Methane cycling in peat bogs: Environmental relevance of methano-Trophs revealed by microbial lipid chemistry. LPP Contribution Series (35)

    NARCIS (Netherlands)

    van Winden, J.F.

    2011-01-01

    Global warming is continuing without delay and this is caused by the accumulation of greenhouse gases in the atmosphere. Methane is a strong greenhouse gas, 25 times stronger compared to CO2. The increase in methane concentrations in the atmosphere is largely the result of human influences, but ther

  4. Flight Morphology, Compound Eye Structure and Dispersal in the Bog and the Cranberry Fritillary Butterflies: An Inter- and Intraspecific Comparison.

    Science.gov (United States)

    Turlure, Camille; Schtickzelle, Nicolas; Van Dyck, Hans; Seymoure, Brett; Rutowski, Ronald

    2016-01-01

    Understanding dispersal is of prime importance in conservation and population biology. Individual traits related to motion and navigation during dispersal may differ: (1) among species differing in habitat distribution, which in turn, may lead to interspecific differences in the potential for and costs of dispersal, (2) among populations of a species that experiences different levels of habitat fragmentation; (3) among individuals differing in their dispersal strategy and (4) between the sexes due to sexual differences in behaviour and dispersal tendencies. In butterflies, the visual system plays a central role in dispersal, but exactly how the visual system is related to dispersal has received far less attention than flight morphology. We studied two butterfly species to explore the relationships between flight and eye morphology, and dispersal. We predicted interspecific, intraspecific and intersexual differences for both flight and eye morphology relative to i) species-specific habitat distribution, ii) variation in dispersal strategy within each species and iii) behavioural differences between sexes. However, we did not investigate for potential population differences. We found: (1) sexual differences that presumably reflect different demands on both male and female visual and flight systems, (2) a higher wing loading (i.e. a proxy for flight performance), larger eyes and larger facet sizes in the frontal and lateral region of the eye (i.e. better navigation capacities) in the species inhabiting naturally fragmented habitat compared to the species inhabiting rather continuous habitat, and (3) larger facets in the frontal region in dispersers compared to residents within a species. Hence, dispersers may have similar locomotory capacity but potentially better navigation capacity. Dispersal ecology and evolution have attracted much attention, but there are still significant gaps in our understanding of the mechanisms of dispersal. Unfortunately, for many species we lack detailed information on the role of behavioural, morphological and physiological traits for dispersal. Our novel study supports the existence of inter- and intra-specific evolutionary responses in both motion and navigation capacities (i.e. flight and eye morphology) linked to dispersal.

  5. The effects of ecological restoration, on soil-pore water quality and DOC concentrations, on a British upland blanket bog.

    Science.gov (United States)

    Qassim, Suzane; Dixon, Simon; Rowson, James; Worrall, Fred; Evans, Martin

    2013-04-01

    Polluted by past atmospheric deposition, eroded and burnt, the Bleaklow plateau (Peak district National Park, UK) has long been degraded. Peatlands are important carbon reservoirs and can act as sources or sinks of carbon. Dissolved organic carbon (DOC) is carbon lost from peatlands via the fluvial pathway and as the major component of water colour it is costly to remove during water treatment processes. The Bleaklow Summit peatlands, were subjected to a large wildfire in 2003 devegetating 5.5km2. This fire prompted stakeholders to initiate a large-scale programme of restoration of the plateau. This study considered restoration techniques across four sites: all four sites were seeded with lawn grass, limed and fertilised; to raise the pH and allow establishment of vegetation. In addition to these interventions, one site also had a mulch of Calluna vulgaris applied to the surface to allow soil stabilisation and promote vegetation establishment and another site had biodegradable geojute textile mesh installed, to stabilize the steep gully surfaces. Another site had a gully block installed, to reduce peat desiccation and erosion. This study will compare the four restored sites to two types of comparators: bare soil sites where no restoration was undertaken and a naturally vegetated site unaffected by the 2003 wildfire. Each site had six replicate dipwells, installed in two groups of three. The depth to the water table was monitored and soil water samples collected for analysis, monthly for 5 years, from Nov 2006 - Jan 2012. No significant difference in DOC concentration was found between control and treated sites. There was, however, a significant difference in DOC composition between sites and over the 5 year period of monitoring. UV-vis absorbance of the samples is used to quantify the fulvic to humic components of DOC. The vegetated control was not significantly different to the bare sites; however the vegetated control had a significantly greater humic fraction of than the seeded, limed and fertilised only site, as well as the seeded, limed, C. vulgaris mulched site. This is possibly related to vegetation and litter layer establishment. A suite of water quality data (conductivity, pH and cation data) are now being analysed in combination with DOC to increase understanding of the relationship between bare site re-vegetation and DOC compositional change.

  6. Peat Bog Wildfire Smoke Exposure in Rural North Carolina Is Associated with Cardio-Pulmonary Emergency Department Visits

    Science.gov (United States)

    In June 2008 burning deposits of peat produced haze and air pollution far in excess of National Ambient Air Quality Standards, encroaching on rural communities of eastern North Carolina (NC). While the association of mortality and morbidity with exposure to urban air pollution i...

  7. Peat bog wildfire smoke exposure in rural North Carolina is associated with Cardiopulmonary emergency department visits assessed through syndromic surveillance

    Science.gov (United States)

    Background: In June 2008 burning deposits of peat produced haze and air pollution far in excess of National Ambient Air Quality Standards, encroaching on rural communities of eastern North Carolina (NC). While the association of mortality and morbidity with exposure to urban air ...

  8. Sources of Below-Ground Respired Carbon in a Northern Minnesota Ombrotrophic Spruce Bog and the Influence of Heating Manipulations.

    Science.gov (United States)

    Guilderson, T. P.; McFarlane, K. J.; McNicol, G.; Hanson, P. J.; Chanton, J.; Wilson, R.; Bosworth, R.; Singleton, M. J.

    2015-12-01

    A significant uncertainty in future land-surface carbon budgets is the response of wetlands to climate change. A related question is the future net climate (radiative) forcing impact due to ecosystem and environmental change in wetlands. Active wetlands emit both CO2 and CH4 to the atmosphere. CH4 is, over a few decades, a much more potent greenhouse gas than CO2 whereas as a consequence of a much longer atmospheric lifetime, CO2 has a longer 'tail' to its influence. Whether wetlands are a net source or sink of atmospheric carbon under future climate change will depend on the response of the ecosystem to rising temperatures and elevated CO2. The largest uncertainty in future wetland budgets, and its climate forcing, is the stability of the large belowground carbon stocks, often in the form of peat, and the partitioning of CO2 and CH4released via ecosystem respiration. We have characterized the isotopic signatures (14,13C of CO2 and CH4, D-CH4) of the respired carbon used for the production of CO2 and CH4 from the DOE Spruce and Peatland Responses Under Climatic and Environmental Change (SPRUCE) site in the Marcell Experimental Forest, which contains replicated mesocosm manipulations including above/below ground warming and elevated CO2. Deep warming (1-2 m) was initiated in July of 2014 and above ground heating will be initiated in July 2015. Comparison of the respired CO2 and CH4with recently fixed photosynthate, below-ground peat (up to 11,000 years old), and dissolved organic carbon allow us to determine the primary substrates used by the microbial community. Control and pre-perturbed plots are characterized by the consumption and respiration of recently fixed photosynthate and recent (few years to 15 yr) carbon. Although CH4 fluxes have begun to respond to deep-heating, the source of carbon remains similar in the control and perturbed plots. Respired CO2 remains consistent with being sourced from carbon only a few years old. We will present additional data collected in July, August, and September 2015 which will include the combined influence of above and belowground heating.

  9. Between Bog Bodies and High Halls. Changes in Spatial Focus and Religious Conceptions in the Pre-Christian North

    DEFF Research Database (Denmark)

    Nygaard, Simon

    2015-01-01

    Abstract prepared and accepted for The Sixteenth International Saga Conference: Sagas and Space, Zürich 2015. Due to personal reasons, the actual paper was not presented at the conference, but at a Saga Seminar in Aarhus later the same year. Published in the Preprints of Abstracts for the Saga Co...

  10. A Greener Arctic: Vascular Plant Litter Input in Subarctic Peat Bogs Changes Soil Invertebrate Diets and Decomposition Patterns

    Science.gov (United States)

    Krab, E. J.; Berg, M. P.; Aerts, R.; van Logtestijn, R. S. P.; Cornelissen, H. H. C.

    2014-12-01

    Climate-change-induced trends towards shrub dominance in subarctic, moss-dominated peatlands will most likely have large effects on soil carbon (C) dynamics through an input of more easily decomposable litter. The mechanisms by which this increase in vascular litter input interacts with the abundance and diet-choice of the decomposer community to alter C-processing have, however, not yet been unraveled. We used a novel 13C tracer approach to link invertebrate species composition (Collembola), abundance and species-specific feeding behavior to C-processing of vascular and peat moss litters. We incubated different litter mixtures, 100% Sphagnum moss litter, 100% Betula leaf litter, and a 50/50 mixture of both, in mesocosms for 406 days. We revealed the transfer of C from the litters to the soil invertebrate species by 13C labeling of each of the litter types and assessed 13C signatures of the invertebrates Collembola species composition differed significantly between Sphagnum and Betula litter. Within the 'single type litter' mesocosms, Collembola species showed different 13C signatures, implying species-specific differences in diet choice. Surprisingly, the species composition and Collembola abundance changed relatively little as a consequence of Betula input to a Sphagnum based system. Their diet choice, however, changed drastically; species-specific differences in diet choice disappeared and approximately 67% of the food ingested by all Collembola originated from Betula litter. Furthermore, litter decomposition patterns corresponded to these findings; mass loss of Betula increased from 16.1% to 26.2% when decomposing in combination with Sphagnum, while Sphagnum decomposed even slower in combination with Betula litter (1.9%) than alone (4.7%). This study is the first to empirically show that collective diet shifts of the peatland decomposer community from mosses towards vascular plant litter may drive altered decomposition patterns. In addition, we showed that although species-specific differences in Collembola feeding behavior appear to exist, species are very plastic in their diet. This implies that changes in C turnover rates with vegetation shifts, might well be due to diet shifts of the present decomposer community rather than by changes in species composition.

  11. The content and UV-Vis absorbances of bog peat organic matter fractions (Divčivare, Serbia

    Directory of Open Access Journals (Sweden)

    Petrović Petar G.

    2015-01-01

    Full Text Available This paper presents peat soil organic matter characteristics at Divčibare Mountain (950 m a.s.l, mountain climate. Excessive wetting is caused by groundwater and floods, and plant litter originates from hydrophilic vegetation. An investigation was aimed at determining the correlation between organic matter characteristics (humification degree, stability and bioavailability with factors of soil formation and the most important physico-chemical characteristics of peat. Peat is mild acid and has a low base saturation. The content of organic matter is higher than 60% at depth of 40−80 cm, and higher than 40% at depths of 0−40 and 80−105 cm, respectively. Investigated peat had sapric characteristics. A content of humic acids in total organic matter indicates its unequal humification degree within profile, moderate to high at depth of 0−40 cm, low at 40−80-cm depth, and very low beneath 80 cm. A value of Ch/Cf ratio indicates high humus stability up to 80 cm where it has humate-type humus, while below 80 cm humus is the humatefulvate type. A low content of fractions separated with 0.1N cold H2SO4, and cold and hot water, points out a low bioavailability of organic matter through whole soil profile. UV-Vis indices indicate a low humification degree of humic acids (increased to 80-cm depth, and a very low humification degree of fulvic acids (variable, the highest at 60−80-cm depth. Overall results indicate that particle size of mineral fraction, soil reaction, and cation exchange capacity had no significant impact on organic matter characteristics. Soil moisture content, that is alterations of oxido-reductive conditions throughout soil profile had the crucial impact on peat organic matter characteristics.

  12. The dynamics of lake, bog, and bay - Consequences of exposure to man related to final storage of spent nuclear fuel

    International Nuclear Information System (INIS)

    The natural aging of the environment, much shorter than a possible continuous release from a repository, results in uncertainties as regards to consequences of exposure to man related to final storage of spent fuel. The Phase I project summarizes the identification of such factors and parameters of predominant importance for an assessment of possible radiological consequences in a normally revolving biosphere. Three major areas are described: geomorphology and residence time such as phenomena associated with the formation of lakes in Sweden formed by the latest inland ice, lake development in terms of uptake of different elements and radionuclides as a function of the chemical composition of the water in a recipient and some aspects of sedimentation in lakes and coastal waters. The chemical environment is also studied in the evolution of a lake or a Baltic bay into farming land or peat land. The most important parameters to the behaviour of trace metal ions seem to be pH, Eh, ionic strength and content of complex formers. Finally, the human impact during the evolution of a lake or a bay is discussed. The study also includes recommendation for a reference field test area and for laboratory studies of the chemical properties of radionuclides in sediments in a Phase 2 project. (Author)

  13. A influência dos bogs de moda no processo de decisão de compra

    OpenAIRE

    Costa, Marta Correia Barros da

    2015-01-01

    As redes sociais, nas quais se incluem os blogs, vieram alterar a forma como as pessoas escolhem os bens e serviços que pretendem adquirir. Ao permitirem (entre outras coisas) a emissão para o mundo de opiniões sobre produtos e serviços, as redes sociais aumentaram a quantidade de informação pré-compra disponível, bem como diversificaram o tipo de fontes que é possível consultar durante este processo. Um exemplo flagrante deste fenómeno em Portugal, e no resto do Mundo, são os blogs de mod...

  14. 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

    ... centrifugal refrigeration compressor; A cryogenic plate-fin heat exchanger; Ancillary aerial coolers, knockout vessels, pumps, and piping for the closed loop refrigeration cycle; Four small (less than 10,000...

  15. 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

    , ikke mindst med hensyn til værdirelativismen. Rasmussen viser, at komplementaritetsbegrebet i Bohrs vigtige men oversete filosofi kan bidrage væsentligt til at afklare teoretisk-metodiske problemer i statskundskab, herunder forholdet mellem struktur og handling og mellem mikro- og makroanalyse, samt...... 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....

  16. How a Sphagnum fuscum-dominated bog changed into a calcareous fen : the unique Holocene history of a Slovak spring-fed mire

    NARCIS (Netherlands)

    Hajkova, Petra; Grootjans, A. B.; Lamentowicz, Mariusz; Rybnickova, Eliska; Madaras, Mikulas; Opravilova, Vera; Michaelis, Dierk; Hajek, Michal; Joosten, Hans; Wolejko, Leslaw; Rybníčková, Eliška; Madaras, Mikuláš; Opravilová, Věra; Wołejko, Lesław; Hajkova, T.

    2012-01-01

    In general, mires develop by autogenic succession from more groundwater-fed to more rainwater-fed. This study from a calcareous mire in the West Carpathians (Slovakia) describes a similar development in the Early Holocene, followed by a reverse development in the Middle and Late Holocene. Pollen, ma

  17. Effects of grass species and grass growth on atmospheric nitrogen deposition to a bog ecosystem surrounded by intensive agricultural land use

    Science.gov (United States)

    Hurkuck, Miriam; Brümmer, Christian; Mohr, Karsten; Spott, Oliver; Well, Reinhard; Flessa, Heinz; Kutsch, Werner L

    2015-01-01

    We applied a 15N dilution technique called “Integrated Total Nitrogen Input” (ITNI) to quantify annual atmospheric N input into a peatland surrounded by intensive agricultural practices over a 2-year period. Grass species and grass growth effects on atmospheric N deposition were investigated using Lolium multiflorum and Eriophorum vaginatum and different levels of added N resulting in increased biomass production. Plant biomass production was positively correlated with atmospheric N uptake (up to 102.7 mg N pot−1) when using Lolium multiflorum. In contrast, atmospheric N deposition to Eriophorum vaginatum did not show a clear dependency to produced biomass and ranged from 81.9 to 138.2 mg N pot−1. Both species revealed a relationship between atmospheric N input and total biomass N contents. Airborne N deposition varied from about 24 to 55 kg N ha−1 yr−1. Partitioning of airborne N within the monitor system differed such that most of the deposited N was found in roots of Eriophorum vaginatum while the highest share was allocated in aboveground biomass of Lolium multiflorum. Compared to other approaches determining atmospheric N deposition, ITNI showed highest airborne N input and an up to fivefold exceedance of the ecosystem-specific critical load of 5–10 kg N ha−1 yr−1. PMID:26257870

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

    Directory of Open Access Journals (Sweden)

    Alinne Balduino P. Fernandes

    2015-12-01

    an individual task, originating in the complex act of reading the play-text, its final trajectory is deeply influenced by the creative insights of the production team. The overarching objectives of this article are, therefore: firstly to account for the overall process of translating for the stage, from the early drafts of the translation to the rehearsal process, and ultimately to the staged reading of the play; and secondly, to offer a narrative for how the cultural encounter between the exporting and importing cultures has taken place through translation and theatrical performance.

  19. Enzyme activity in forest peat soils

    OpenAIRE

    Błońska, Ewa

    2010-01-01

    The aim of the study was to determine the activity of dehydrogenases and urease in forest peat soils of different fertility. There were selected 23 experimental plots localised in central and northern Poland. The research was conducted on forest fens, transition bogs and raised bogs. The biggest differences in soil physical and chemical properties were detected between fen and raised bog soils while raised bog soils and transition bog soils differed the least. Statistically significant dif...

  20. Peat; La tourbe

    Energy Technology Data Exchange (ETDEWEB)

    Hervio, J.M. [Federation des Conservatoires regionaux d' espaces Naturels, 45 - Orleans (France); Millet, M.; Taborin, J.; Barthelemy, F.; Richard, H.; Begeot, C.; Magny, M.; Bossuet, G.; Megnien, C.; Buffetaut, E.; Duffaut, P.

    1999-09-01

    Peat bogs represent 4 millions of km{sup 2}, i.e. 3% of the Earth's surface. 90% are located in temperate and cold regions of the northern hemisphere mainly in Russia, Canada, USA and Scandinavia. This dossier is entirely devoted to peat. After a recall of the historical development of peat uses, the different types of peat bogs are presented (mires or fen peats, raised bogs). Then, different aspects of peat bogs are presented successively: natural resources and fragile ecosystems of humid regions (peat bogs, peat, deposits, formation, typology, geographical distribution, physico-chemical characteristics and uses, production, prices, market and fluxes, evolution and perspectives); peat bogs as todays environmental models of humic coals (generalities, composition of peat, degradation and preservation of plants, the lignin bio-marker, geological evolution of peat); peat and the recording of climatic changes; the French national strategy of peat bogs conservation; the origin of peat bogs in Jura (France); Baupte: a French peat bog in exploitation; the Cerin lake peat bog (southern Jura, France); the Blackwater bog (Offaly county, Ireland): industrial exploitation, the ancient artisanal exploitation, cross section and archaeological discoveries; the tropical peat bogs (continental-type: genesis and evolution, mangrove-type); the Pleistocene Megaloceros deer; peat and the manufacturing of whisky; the paleontological study of a Canadian peat bog; the archaeological discoveries of Northern Europe peat bogs; the problem of building onto peat. (J.S.)

  1. 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)...

  2. Evaluering af lokale udviklingsprocesser

    DEFF Research Database (Denmark)

    Rasbech Nielsen, Mie; Jensen, Bente

    Arbejdspapir udviklet til HPA-projektet 2007. Revideret, nyt forord, ISBN nummer og udgivet som e-bog......Arbejdspapir udviklet til HPA-projektet 2007. Revideret, nyt forord, ISBN nummer og udgivet som e-bog...

  3. Dansk sang som identitetshistorie

    DEFF Research Database (Denmark)

    Bonde, Lars Ole

    2008-01-01

    Anmeldelse af Georg Metz' bog med kultur- og identitetshistoriske kommentarer til 117 danske sange, salmer og viser. Udgivelsesdato: 201108......Anmeldelse af Georg Metz' bog med kultur- og identitetshistoriske kommentarer til 117 danske sange, salmer og viser. Udgivelsesdato: 201108...

  4. 笃斯越桔多酚提取物成分分析及其抗氧化活性的研究%Composition analysis and antioxidant activity of bog bilberry polyphenol extract

    Institute of Scientific and Technical Information of China (English)

    柳嘉; 赵竞; 景浩

    2009-01-01

    研究笃斯越桔(Vaccinium uliginosum Linn)多酚提取物的成分、花青素组分和抗氧化能力.采用Bradford法和苯酚-硫酸法分别测定提取物中蛋白质和总糖的含量,Folin-ciocaheu法测定总多酚含量.进一步采用RP-HPLC分析笃斯越桔多酚提取物中花青素组分.结果表明,笃斯越桔多酚提取物中多酚含量占干质量的61.7%,花青素组分为5种,矢车菊素-3-葡萄糖苷为其主要成分.采用ABTS法和DPPH法评价提取物的抗氧化活性.结果显示,笃斯越桔多酚提取物清除ABTS和DPPH自由基的能力随提取物剂量的增加而升高,且EC50分别为114.1 μg/mL和1 16.0μg/mL,而标准品Trolox的EC50分别为129.0 μg/mL和130.6μg/mL.笃斯越桔多酚提取物多酚含量高,抗氧化能力强,是一种有效的天然抗氧化剂.

  5. Multi-proxy analyses of a peat bog on Isla de los Estados, easternmost Tierra del Fuego: a unique record of the variable Southern Hemisphere Westerlies since the last deglaciation

    Science.gov (United States)

    Björck, Svante; Rundgren, Mats; Ljung, Karl; Unkel, Ingmar; Wallin, Åsa

    2012-05-01

    We have analyzed an almost 14,000 year old peat sequence on the island of Isla de los Estados (55° S, 64° W), east of Tierra del Fuego, in the core of the Southern Hemisphere Westerlies. A multitude of methods have been used: high resolution 14C dating; detailed lithologic descriptions including humification degree; loss on ignition; magnetic susceptibility; bulk density; pollen and spore analysis and determination of Aeolian sand influx. By combining proxies for wind and precipitation we have been able to reconstruct how the westerlies have varied over time in the Atlantic sector of the Southern Ocean. It shows that this westerly wind belt was most intense at the onset of the record, 13,600-13,200 cal BP, coinciding with the mid to late part of the Antarctic Cold Reversal, followed by a gradual decline. At 12,200 cal BP the westerlies seem to have shifted to a position south of Tierra del Fuego and this phase, the calmest and driest period on the island throughout the sequence, ended at 10,000 cal BP when the westerlies moved equatorward again. Since then the westerlies have been present but with a variable impact on the 55° S latitude of the Atlantic. Mostly conditions have been fairly similar to today, but occasionally with a wider or narrower and/or weaker or stronger wind belt. At 7200 cal BP wind intensity began to increase and between 4500 and 3500 cal BP these southern latitudes experienced a distinct wind and precipitation maximum, both in terms of perseverance and intensity. Our results show a both wide and strong wind belt, with possible niveo-aeolian activity in Tierra del Fuego in winter, and possibly creating milder summers around the Antarctic Peninsula. In the later part of the Holocene, expansion-contraction phases of the wind belt, especially in winter, seem to have been a common phenomenon.

  6. Characterisation of Sanguinhal Mire, Terceira Island (Azores: a protected quaking bog habitat Caracterização da Turfeira do Sanguinhal, ilha Terceira (Açores um habitat protegido de turfeira ondulante

    Directory of Open Access Journals (Sweden)

    Cândida Mendes

    2009-09-01

    Full Text Available The Azores archipelago in the North Atlantic is an important area for biodiversity because it is rich in rare species and habitats, and almost undisturbed. Sanguinhal mire was originally a lake that evolved through paludification into a peat habitat. It is located inside Nature 2000 (European Union for Protection of Nature and Biodiversity, Council Directive 92/43/EEC of 21 May 1992 on the conservation of natural habitats and of wild fauna and flora, Habitat Directive Annex I(b habitat 7140 area of Santa Bárbara and Pico Alto Mountains on the island of Terceira, and it is a good example of a basin peatland type that was first discovered in 1998. This paper provides baseline information on its flora, vegetation communities, structure, surface hydrology and chemistry. Forty-one plant species including six Sphagnum species and ten endemic vascular plants have been recorded, and eight plant communities are distinguished. The maximum peat depth is 2.5 m. The mire receives flowing water from its margins, in addition to intercepted precipitation and fog. After precipitation, water drains through several placic rupture points. Both pH and water conductivity were measured, with some ecological tendencies observed. The conservation status of the mire is good, but it is subject to increasing pressure from cattle pasture and a walking trail that constrains natural surface water movement.O Arquipélago dos Açores no Atlântico Norte é uma área importante em biodiversidade, rica em espécies e habitats raros em estado selvagem. A turfeira do Sanguinhal foi originalmente uma lagoa que evoluiu por paludificação para um habitat de turfa. Esta localiza-se na Rede Natura 2000 (União Europeia para a Proteção da Natureza e Biodiversidade, Directive do Conselho 92/43/EEC de 21 de Maio 1992 sobre a concervação de habitats naturais e da fauna e flora, Diretiva de Habitat Anexo I(b habitat 7140 da Serra de Santa Bárbara e Pico Alto e é um bom exemplo de um tipo de turfeira de bacia, descoberto pela primeira vez em 1998. Este trabalho provê informações iniciais sobre a flora, as comunidades vegetais, a estrutura, as caracteristicas químicas da água e o regime hidrológico de superfície. Foram identificadas 41 espécies vegetais, incluindo 6 espécies do género Sphagnum, e 10 espécies de plantas vasculares endêmicas, forma identificadas oito comunidades vegetais. A profundidade máxima de turfa é de 2,5 m. A turfeira recebe água superficial de suas margens, além da precipitação interceptada e da névoa. Depois das chuvas, a água é drenada por vários pontos da turfeira onde o placic se rompeu. O pH e a condutividade das água foram medidos tendo-se verificado algumas tendências. O estado de conservação da turfeira é bom embora esteja sujeita a um crescente pastoreio por gado selvagem e a abertura de trilhos de forma desordenada altera o natural movimento de água na turfeira.

  7. Steady-state and dynamic simulation study on boil-off gas minimization and recovery strategies at LNG exporting terminals

    Science.gov (United States)

    Kurle, Yogesh

    Liquefied natural gas (LNG) is becoming one of the prominent clean energy sources with its abundance, high calorific value, low emission, and price. Vapors generated from LNG due to heat leak are called boil-off gas (BOG). As world-wide LNG productions are increasing fast, BOG generation and handling problems are becoming more critical. Also, due to stringent environmental regulations, flaring of BOG is not a viable option. In this study, typical Propane-and-Mixed-Refrigerant (C3-MR) process, storage facilities, and loading facilities are modeled and simulated to study BOG generation at LNG exporting terminals, including LNG processing, storage, and berth loading areas. Factors causing BOG are presented, and quantities of BOG generated due to each factor at each location are calculated under different LNG temperatures. Various strategies to minimize, recover, and reuse BOG are also studied for their feasibility and energy requirements. Rate of BOG generation during LNG loading---Jetty BOG (JBOG)---changes significantly with loading time. In this study, LNG vessel loading is simulated using dynamic process simulation software to obtain JBOG generation profile and to study JBOG recovery strategies. Also, fuel requirements for LNG plant to run steam-turbine driven compressors and gas-turbine driven compressors are calculated. Handling of JBOG generated from multiple loadings is also considered. The study would help proper handling of BOG problems in terms of minimizing flaring at LNG exporting terminals, and thus reducing waste, saving energy, and protecting surrounding environments.

  8. Struktura przestrzenna roślinności torfowiska Żabieniec koło Brzezin

    OpenAIRE

    Cieślak, Piotr

    2000-01-01

    In the paper are presented results of researches on flora, plant communities and spatial structure of vegetation of the Żabieniec peat bog. These researches were carried out in the years 1995-1996. In the peat bog 17 plant communities were distinguished. They belong to 5 ecological groups: forests and scrubs (3), rushes (5), meadows (4), water communities (3) and peat communities (2). The paper contains also a map of real vegetation, 2 profiles of vegetation of peat bog, and...

  9. Breeding bird populations of Irish peatlands : capsule peatlands are very important habitats for birds despite low species diversity

    OpenAIRE

    Bracken, Fintan; Barry J. McMahon; Whelan, John

    2008-01-01

    Aims to describe the variation in breeding bird populations that occur on different types of Irish peatlands and their associated habitat characteristics. Methods: Bird abundance and diversity were compared between four peatland habitat types: fens; raised bogs; Atlantic blanket bogs; and montane blanket bogs at twelve study sites using transects. Various measures of habitat quality were also taken at each location. Results: Only 21 species were recorded during the study with Meadow Pip...

  10. D. Larsen: Fortrængt Grusomhed (Dänische SS-Wächter 1941-45)

    DEFF Research Database (Denmark)

    Hansen, Jens-Christian

    2011-01-01

    Anmeldelse af Dennis Larsens bog "Fortrængt grusomhed. Danske SS-vagter 1941-45" for H-Soz-u-Kult......Anmeldelse af Dennis Larsens bog "Fortrængt grusomhed. Danske SS-vagter 1941-45" for H-Soz-u-Kult...

  11. Natur og udeliv

    DEFF Research Database (Denmark)

    Ejbye-Ernst, Niels; Stokholm, Dorte

    I-bog til valgmodulet "Natur og udeliv" Bogen gennemgår væsentlige temaer i valgmodulet og underbygger med video, praksisfortællinger mv.......I-bog til valgmodulet "Natur og udeliv" Bogen gennemgår væsentlige temaer i valgmodulet og underbygger med video, praksisfortællinger mv....

  12. Ved vejen

    DEFF Research Database (Denmark)

    Dahl, Per; Dalsgaard, Birgitte

    2012-01-01

    iBogs-udgave af Herman Bang: Ved Vejen, inkl. 646 ordforklaringer, 4 introduktioner, 4 anmeldelser, opgaver, 4 videoklip, 1 lydfil, 48 illustrationer, 3 stilesæt, litteraturliste......iBogs-udgave af Herman Bang: Ved Vejen, inkl. 646 ordforklaringer, 4 introduktioner, 4 anmeldelser, opgaver, 4 videoklip, 1 lydfil, 48 illustrationer, 3 stilesæt, litteraturliste...

  13. 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

    Sixty consecutive patients suspected of having bacterial overgrowth of the small intestine (BOG) had aerobic and anaerobic bacterial cultures made of fasting upper jejunal fluid and also a 14C-D-xylose breath test (XBT). Culture-proven BOG was present in 23 patients. In another 15 patients the pr...

  14. [Financial Aid to Independent Students at the Post Secondary Level: The Federal Government's Role

    Science.gov (United States)

    Dellenback, John

    One of the new and complex issues related to student aid is the independent student controversy. The author wishes to increase the Basic Opportunity Grant (BOG) and substantially increase work study to help the independent student. For the immediate future the author would like to see: (1) The BOG refined as a major Federal grant program committed…

  15. Armillaria ectypa, a rare fungus of mire in Poland

    Directory of Open Access Journals (Sweden)

    Małgorzata Stasińska

    2015-08-01

    Full Text Available Armillaria ectypa is a saprotroph that occurs on active raised bogs and alkaline fens, as well as Aapa mires and transitional bogs. It is a very rare and threatened Eurasian species and one of the 33 fungal species proposed for inclusion into the Bern Convention. Its distribution in Poland, ecological notes and morphology of basidiocarp based on Polish specimens are presented.

  16. 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...

  17. E-bogen som udfordring for folkebibliotekernes almendidaktiske opgaver

    DEFF Research Database (Denmark)

    Skøtt, Bo

    2016-01-01

    Dette kapitlet belyser folkebibliotekernes almendidaktiske opgaver, og hvordan disse omformes af den igangværende digitalisering, især med fokus på overgang fra bog til e-bog. Udgangspunktet er, at ændringer i materielle vilkår og betingelser fordrer en række nye kompetencer, for at det enkelte...

  18. Distance Education Report, 2011-2012

    Science.gov (United States)

    California Community Colleges, Chancellor's Office, 2013

    2013-01-01

    This is a report on distance education in the California Community College. This is the seventh report to the California Community Colleges Board of Governors (BOG) per BOG Standing Order 409 (b) "that evaluates the effectiveness of distance education and education technology system wide and provides analysis of data demographically (by age,…

  19. 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....

  20. Deltagende observation 2. udgave

    DEFF Research Database (Denmark)

    Kristiansen, Søren; Krogstrup, Hanne Kathrine

    Denne bog er en teoretisk og praktisk introduktion til deltagende observation, og giver konkrete anvisninger, som er nyttige for såvel erfarne som den uprøvede feltforsker.......Denne bog er en teoretisk og praktisk introduktion til deltagende observation, og giver konkrete anvisninger, som er nyttige for såvel erfarne som den uprøvede feltforsker....

  1. Thomas A. Sebeok and the Astonishing world of Semiotics

    DEFF Research Database (Denmark)

    Gustafsson, Jan

    2012-01-01

    Der er tale om en anmelselse af ovennævnte bog, et festskrift for T. A. Sebeok, en af det 20. århundredes vigtigste semiotikere......Der er tale om en anmelselse af ovennævnte bog, et festskrift for T. A. Sebeok, en af det 20. århundredes vigtigste semiotikere...

  2. Capability Approach

    DEFF Research Database (Denmark)

    Kjeldsen, Christian Christrup; Jensen, Hans Iskov

    2010-01-01

    En kort og introducerende bog om Martha Nussbaums ti centrale kapabiliteter i relation til unge med særlige behov......En kort og introducerende bog om Martha Nussbaums ti centrale kapabiliteter i relation til unge med særlige behov...

  3. Modelling of Boil-Off Gas in LNG Tanks: A Case Study

    Directory of Open Access Journals (Sweden)

    Sheikh Zahidul Islam

    2010-08-01

    Full Text Available This paper focuses on the effect of pressure and heat leakages on Boil-off Gas (BOG in Liquefied Natural Gas (LNG tanks. The Lee-Kesler-Plocker (LKP and the Starling modified Benedict-Webb-Rubin (BWRS empirical models were used to simulate the compressibility factor, enthalpy and hence heat leakage at various pressures to determine the factors that affect the BOG in typical LNG tanks of different capacities. Using a case study data the heat leakage of 140,000kl, 160,00kl, 180,000kl and 200,000kl LNG tanks were analyzed using the LKP and BWRS models. The heat leakage of LNG tanks depends on the structure of tanks, and the small tanks lose heatto the environment due to their large surface area to volume ratio. As the operation pressure was dropped to 200mbar, all four of the LNG tanks’ BOG levels reached 0.05vol%/day. In order to satisfy the BOG design requirement, the operating pressure of the four large LNG tanks in the case study was maintained above 200mbar. Thus, the operating pressure impacts BOG on LNG tanks, but this effect is limited under the extreme high operation pressure. An attempt was made to determine the relationship between the compositions of LNGand BOG; one been combustible and the other non-combustible gases. The main component of combustible gas was methane, and nitrogen was of non-combustible gases. The relationship between BOG and methane compositions was that, as the methane fraction increases in the LNG, the BOG volume also increases. In general, results showed a direct correlation between BOG and operating pressure. The study also found that larger LNG tanks have less BOG; however as the operation pressure is increased the differences in the quantity of BOGamong the four tanks decreased.

  4. The Race Memory and Poetry Meditation bencath ghe Bog:A Cultural Construing to The Tollund Man%沼泽下的民族记忆与诗意沉思--西默斯·希尼《托兰人》的文化解读

    Institute of Scientific and Technical Information of China (English)

    白杰; 尚婷

    2005-01-01

    是1995年诺贝尔文学奖得主西默斯·希尼的著名诗作之一.沼泽为诗人的文学创作提供了极其重要的精神资源,而在沼泽地发现的"托兰人"尸体则寄托了诗人对北爱尔兰长期的宗教战争、民族冲突的关切与困惑.从民族、宗教文化面对进行深入解读,可深切领会到诗人悲悯、迷茫、焦灼而痛苦的内心世界.

  5. Needle anatomy suggests hybridization between the relict turfosa form of Pinus sylvestris L. from the Gązwa peat bóg and typical Scots pine

    OpenAIRE

    Kornelia Polok; Marta Przybyła; Włodzimierz Pisarek; Ewa Chudzińska; Roman Zieliński; Lech Urbaniak

    2011-01-01

    The aim of this study was to characterize the turfosa form of Pinus sylvestris from the Gazwa peat bog reserve in terms of 16 anatomical needle traits and to determine whether pines with a typical morphotype inhabiting the peat bog have been so successful thanks to hybridization with the unique tufosa ecotype. Investigations were conducted on three phenotypic groups of Scots pine growing in the peat bog. The first two groups consisted of 30 tufosa trees at the age of 117-217 years and 20 tree...

  6. The effects of different substrates on flowering of kohleria (Kohleria amabilis Hook.

    Directory of Open Access Journals (Sweden)

    Jerzy Hetman

    2012-12-01

    Full Text Available The aim of the study was to test the effects of different substrates on flowering of Kohleria amabilis Hook. belonging to Gesneriaceae family. Substrates used were: white peat, white peat + bark (1:1, white peat +perlite (1:1, white peat + sand (1:1, coir, low-bog peat, low-bog peat + bark (1:1. Substrates caused effects on flowering of a kohleria. The best of them occured low-bog peat + bark (1:1. Plants bloomed the earliest, for the longest time and plentyfully. Moreover they were hight and nicely leafy. The least useful was white peat.

  7. Sekundäre Moorbildungen abgetorfter Parzellen des Robenhauser Rieds (Pfäffikersee/ZH, Schweiz)

    OpenAIRE

    Burga, C. A.; Schartner, M

    2008-01-01

    The bog of Robenhausen near Seegräben-Wetzikon (Zurich Oberland) belongs to a peatland complex in the nature conservation area of the Lake of Pfäffikon which is surrounded by glacial deposits such as moraines and drumlins. For more than 200 years peat has been used as source of fuel. Since 1996 the bog has become an important nature-conservation and regional recreation area. Primary and secondary peat build-up processes have been studied at 12 core drilling sites within this peat bog. Differe...

  8. 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...

  9. Испытанные временем / Тийна Кольк

    Index Scriptorium Estoniae

    Кольк, Тийна

    2011-01-01

    Ajaproovile vastupannud klassikalise disainiga toodetest: viini tool, Alvar Aalto taburet ja vaas "Savoy", Arne Jacobseni tugitool "Muna" jt. Kaidi Ploomipuu kavandatud Euroopa disainiauhinna Red Dot pälvinud vaip «Bog 4053»

  10. CRISIS FOCUS Fundamentals,Confidence and Policy

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Entering the third year of the most serious economic crisis since the Great Depression, the world economy is still bogged down on the muddy road to recovery. The latest edition of Standard Chartered Bank’s monthly report, Global Focus,

  11. 76 FR 14984 - Sunkhaze Meadows National Wildlife Refuge, Penobscot, Kennebec, and Waldo Counties, ME, and...

    Science.gov (United States)

    2011-03-18

    ...-southwest orientation and, with its six tributaries, creates a diversity of wetland communities. The bog and... been listed by the Partners-in-Flight organization as species that are declining. Slender blue...

  12. 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....

  13. 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...

  14. Is Management Interdisciplinary? The Evolution of Management as an Interdisciplinary Field of Research and Education in the Netherlands

    NARCIS (Netherlands)

    P.J. van Baalen (Peter); L. Karsten (Luchien)

    2007-01-01

    textabstractManagement research and education are often characterized as being interdisciplinary. However, most discussions on what interdisciplinarity in management studies means have bogged down in ideological fixations. In this paper we alternatively take a historical perspective and analyze the

  15. 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....

  16. 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" ....

  17. Sten fra himlen

    DEFF Research Database (Denmark)

    Pedersen, Jens Olaf Pepke

    2012-01-01

    Meteoritter. Veloplagt bog har samlet historien om de mest berømte af dem – fra Yucatan-meteoritten, som ændrede livet på Jorden, til Maribo-meteoritten, der landede i Danmark i 2009.......Meteoritter. Veloplagt bog har samlet historien om de mest berømte af dem – fra Yucatan-meteoritten, som ændrede livet på Jorden, til Maribo-meteoritten, der landede i Danmark i 2009....

  18. Needle anatomy suggests hybridization between the relict turfosa form of Pinus sylvestris L. from the Gązwa peat bóg and typical Scots pine

    Directory of Open Access Journals (Sweden)

    Kornelia Polok

    2011-04-01

    Full Text Available The aim of this study was to characterize the turfosa form of Pinus sylvestris from the Gazwa peat bog reserve in terms of 16 anatomical needle traits and to determine whether pines with a typical morphotype inhabiting the peat bog have been so successful thanks to hybridization with the unique tufosa ecotype. Investigations were conducted on three phenotypic groups of Scots pine growing in the peat bog. The first two groups consisted of 30 tufosa trees at the age of 117-217 years and 20 trees at the age of 30-85 years. The third group consisted of typical pines represented by 10 trees at the age of 20-55 years. In total 30 trees of typical pine, surrounding the peat bog, at the age of 100-150 years served as outgroup. Descriptive statistics, analysis of variance with the F test, Tukey's test, and a number of multivariate analyses were used to estimate differences between the studied groups of trees based on 16 anatomical needle characteristics. The old turfosa form from the Gazwa reserve proved to be a unique and relict peat bog pine, as it was shown by the differences in 10 analyzed needle traits in comparison to pine with a typical morphotype growing in the areas surrounding the peat bog. The young typical pines have adapted to conditions found in the peat bog owing to hybridization with the turfosa forms. The young turfosa trees differed from the old turfosa trees and also they have probably been of a hybrid origin. The old turfosa form from the Gazwa reserve is a threatened ecotype due to its hybridization with pines from the population surrounding the peat bog.

  19. Den, som protesterer, er gået i fælden

    DEFF Research Database (Denmark)

    Kondrup, Johnny Johansen

    2007-01-01

    En litteraturhistorisk kommentar til Knud Romer Jørgensens bog "Den som blinker er bange for døden" (2006), der sammenblander to læserpagter: fiktionspagten ("roman") og referentialitetspagten (selvbiografi).......En litteraturhistorisk kommentar til Knud Romer Jørgensens bog "Den som blinker er bange for døden" (2006), der sammenblander to læserpagter: fiktionspagten ("roman") og referentialitetspagten (selvbiografi)....

  20. Boganmeldelse

    DEFF Research Database (Denmark)

    Lunde, Jens

    2015-01-01

    De amerikanske professorer, Atif Mian og Amir Sufi, udgav i år den udmærkede og noget oversete bog »House of Debt«, der vender fortællingen om finanskrisen på hovedet.......De amerikanske professorer, Atif Mian og Amir Sufi, udgav i år den udmærkede og noget oversete bog »House of Debt«, der vender fortællingen om finanskrisen på hovedet....

  1. Branka Migotti, Roman Empire Crossbow Portrait Brooches

    DEFF Research Database (Denmark)

    Hansen, Ulla Lund

    2009-01-01

    Ameldelse ad B. Migottis bog om løgknopfiblers dekoration og datering i relation til kejserportrætlighed mellem fiblernes dekoration og andre objekter med kejserportrætter. Udgivelsesdato: 2009......Ameldelse ad B. Migottis bog om løgknopfiblers dekoration og datering i relation til kejserportrætlighed mellem fiblernes dekoration og andre objekter med kejserportrætter. Udgivelsesdato: 2009...

  2. Studying the removal of the pollutants from wetlands

    OpenAIRE

    Nevzorov Aleksandr Leonidovich; Tel’minov Il’ya Valentinovich

    2015-01-01

    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 plan...

  3. 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....

  4. Social arv

    DEFF Research Database (Denmark)

    Jensen, Bente

    Arbejdspapir som er udarbejdet i forbindelse med HPA-projektet og brugt i en anden udgivelse fra 2007. Nu genudgivet med nyt forord og ISBN nummer, samt udgive via DPU's forlag som e-bog......Arbejdspapir som er udarbejdet i forbindelse med HPA-projektet og brugt i en anden udgivelse fra 2007. Nu genudgivet med nyt forord og ISBN nummer, samt udgive via DPU's forlag som e-bog...

  5. Greece; Selected Issues

    OpenAIRE

    International Monetary Fund

    2013-01-01

    This Selected Issues paper provides updates on Greece’s financial stability framework. The paper highlights that the Bank of Greece (BoG) has strengthened the financial stability framework over recent years. In addition to the liquidity provided by the euro system through its regular refinancing operations and standing facilities, the BoG can provide emergency liquidity assistance (ELA) to financial institutions. In response to the global financial crisis, the authorities have assisted bank...

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

    Science.gov (United States)

    O'Donnell, J. A.; Jorgenson, M.T.; Harden, Jennifer W.; McGuire, A.D.; Kanevskiy, M.Z.; Wickland, K.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.

  7. 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

  8. Impact of long-term drainage on summer groundwater flow patterns in the Mer Bleue peatland, Ontario, Canada

    Science.gov (United States)

    Kopp, B. J.; Fleckenstein, J. H.; Roulet, N. T.; Humphreys, E.; Talbot, J.; Blodau, C.

    2013-09-01

    Long-term impacts of drier conditions on the hydrology of northern peatlands are poorly understood. We used long-term drainage near a historic drainage ditch, separating an area from the main peatland, as an analogue for long-term drying in a northern temperate bog. The objective was to identify the impact of drier conditions on ecohydrological processes and groundwater flow patterns in an area now forested and an area that maintained a bog-like character. Groundwater flow patterns alternated between mostly downward flow and occasionally upward flow in the bog area and were mostly upward-orientated in the forested area, which suggested that there the flow pattern had shifted from bog- to fen-like conditions. Flow patterns were in agreement with changes in post-drainage hydraulic conductivities, storage capacity of the peat and water table levels. Compared to the bog, hydraulic conductivities in the forested area were one to three orders of magnitude lower in the uppermost 0.75 m of peat (paired t test, p forested area. Our findings suggest hydraulic gradients and flow patterns have changed due to increased evapotranspiration and interception with the emergence of a tree cover. The smaller size of the now-forested area relative to the remaining bog area appeared to be important for the hydrological change. With the main Mer Bleue bog as hinterland, enhanced runoff to the drainage channel had little effect on hydrologic and vegetation patterns. In the cut-off, smaller, now forested area pervasive changes in vegetation and hydrologic processes occurred. The difference in response to local drainage raises questions about tipping points with respect to the impact of drying on peatland ecosystems that need to be addressed in future research.

  9. Impact of long-term drainage on summer groundwater flow patterns in the Mer Bleue peatland, Ontario, Canada

    Directory of Open Access Journals (Sweden)

    B. J. Kopp

    2013-09-01

    Full Text Available Long-term impacts of drier conditions on the hydrology of northern peatlands are poorly understood. We used long-term drainage near a historic drainage ditch, separating an area from the main peatland, as an analogue for long-term drying in a northern temperate bog. The objective was to identify the impact of drier conditions on ecohydrological processes and groundwater flow patterns in an area now forested and an area that maintained a bog-like character. Groundwater flow patterns alternated between mostly downward flow and occasionally upward flow in the bog area and were mostly upward-orientated in the forested area, which suggested that there the flow pattern had shifted from bog- to fen-like conditions. Flow patterns were in agreement with changes in post-drainage hydraulic conductivities, storage capacity of the peat and water table levels. Compared to the bog, hydraulic conductivities in the forested area were one to three orders of magnitude lower in the uppermost 0.75 m of peat (paired t test, p < 0.05. Bulk density had increased and the water table level was lower and more strongly fluctuating in the forested area. Our findings suggest hydraulic gradients and flow patterns have changed due to increased evapotranspiration and interception with the emergence of a tree cover. The smaller size of the now-forested area relative to the remaining bog area appeared to be important for the hydrological change. With the main Mer Bleue bog as hinterland, enhanced runoff to the drainage channel had little effect on hydrologic and vegetation patterns. In the cut-off, smaller, now forested area pervasive changes in vegetation and hydrologic processes occurred. The difference in response to local drainage raises questions about tipping points with respect to the impact of drying on peatland ecosystems that need to be addressed in future research.

  10. Cranberry flowering times and climate change in southern Massachusetts

    Science.gov (United States)

    Ellwood, Elizabeth R.; Playfair, Susan R.; Polgar, Caroline A.; Primack, Richard B.

    2014-09-01

    Plants in wild and agricultural settings are being affected by the warmer temperatures associated with climate change. Here we examine the degree to which the iconic New England cranberry, Vaccinium macrocarpon, is exhibiting signs of altered flowering phenology. Using contemporary records from commercial cranberry bogs in southeastern Massachusetts in the United States, we found that cranberry plants are responsive to temperature. Flowering is approximately 2 days earlier for each 1 °C increase in May temperature. We also investigated the relationship between cranberry flowering and flight dates of the bog copper, Lycaena epixanthe—a butterfly dependent upon cranberry plants in its larval stage. Cranberry flowering and bog copper emergence were found to be changing disproportionately over time, suggesting a potential ecological mismatch. The pattern of advanced cranberry flowering over time coupled with increased temperature has implications not only for the relationship between cranberry plants and their insect associates but also for agricultural crops in general and for the commercial cranberry industry.

  11. Preliminary paleoecological reconstruction of long-term relationship between human and environment in the northern part of Danube-along Plain, Hungary

    Science.gov (United States)

    Kustár, Rozália; Molnár, Dávid; Sümegi, Pál; Törőcsik, Tünde; Sávai, Szilvia

    2016-06-01

    The peat bog at Ócsa is located at the northern part of the Danube-Tisa Interfluves at the transitional zone of two landscapes with different morphological characters. At the boundary of the Danube-Tisa Interfluves and the Danube-along Plain a marshland sequence can be found from Hajós to Ócsa. We extended our research to the Ócsa peat bog to complete the environmental historical investigations in the examined area, as well. The bog is located in a former pool formed by the Danube River in which aeolian sand and thick lake sediment deposited from the Late Pleistocene. The initial oligotrophic lake became mesotrophic, therefore thick carbonate sediment deposited. Afterwards, as a consequence of the Neolithic human occupations, the natural development of the lake changed drastically and the lake choked up. The pollen and quartermalacological analysis of the area support the mentioned geological processes.

  12. 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.

  13. Wood anatomy of Argyroxiphium (Asteraceae): adaptive radiation and ecological correlations

    International Nuclear Information System (INIS)

    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)

  14. Analysis and efficiency enhancement of a boil-off gas reliquefaction system with cascade cycle on board LNG carriers

    International Nuclear Information System (INIS)

    Highlights: • An LNG boil-off gas reliquefaction plant on board LNG carriers is improved. • Relevant improvements deals with a study on BOG–C2H4–C3H6 cascade system. • A novel design is proposed to reduce power consumption and COP improvement. • Efficiency improvement by BOG cold energy recovery and compression heat rejection. • Efficiency increase operating in parallel with the engine fuel gas supply system. - Abstract: In this paper, an LNG boil-off gas (BOG) reliquefaction plant operating in accordance with cascade vapor compression cycles, using propylene and ethylene as refrigerants, on board LNG carriers is investigated. As consequence of the analysis results, a new and original design is proposed to reduce power consumption and improve its exergy efficiency. Through energy and exergy analysis, a thermodynamic model is carried out to analyse and evaluate operating conditions as well as to obtain performance values such as the Coefficient of Performance (COP), exergy efficiency, irreversibilities and specific energy consumption. The thermodynamic analysis is performed using the Engineering Equation Solver (EES) software environment. The results of the improved design implemented on the reliquefaction plant for LNG tank conditions of -160.82 °C, a plant BOG input temperature of −125 °C and 25 °C seawater, give COP values of 0.22 and an exergetic efficiency of 37%, such values being 22.22% and 19.35% greater than the original design. The specific energy consumption decreases 14.66% to 0.64 kW h per kg/s of natural BOG. The proposal for improving efficiency is founded on BOG cold energy recovery and BOG compression heat rejection with cooling water in the intercoolers

  15. 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, J.; 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.

  16. Impact of long-term drainage on summer groundwater flow patterns in the Mer Bleue peatland, Ontario, Canada

    Directory of Open Access Journals (Sweden)

    B. J. Kopp

    2013-01-01

    Full Text Available Long-term impacts of a drier climate on coupled hydrology and carbon cycling in northern peatlands are poorly understood. We used a historic drainage ditch, separating an area from the main peatland, as an analogue for long-term drying in a northern temperate bog. The objective was to identify the impact of drier conditions on ecohydrological processes and groundwater flow patterns in an area now wooded and an area that maintained bog character. Groundwater flow patterns alternated between downward flow and upward flow in the bog area and were mostly upward orientated in the wooded area. Flow patterns were in agreement with changes in post-drainage hydraulic conductivities, storage capacity of the peat and hydraulic gradients. Compared to the bog, hydraulic conductivities in the wooded area were one to three orders of magnitude lower in the uppermost 0.75 m (paired t-test, p<0.05 of peat but partly higher below. Bulk density had increased and the water table level was lower and more strongly fluctuating. Our findings suggest hydraulic gradients and flow patterns have changed due to increased evapotranspiration and interception with the emergence of a tree cover. The smaller size of the now-forested area relative to the remaining bog area appeared to be important for the hydrological change. When water supply from undisturbed areas was large, enhanced runoff to the drainage channel had little effect on hydrologic patterns and vegetation pattern, whereas in the smaller, now forested area pervasive changes in vegetation and hydrologic processes occurred. This finding raises questions about tipping points with respect to the impact of drying on bog ecosystems that need to be addressed in future research.

  17. Red list plants: colonization by arbuscular mycorrhizal fungi and dark septate endophytes.

    Science.gov (United States)

    Fuchs, B; Haselwandter, K

    2004-08-01

    Since information concerning the mycorrhization of endangered plants is of major importance for their potential re-establishment, we determined the mycorrhizal status of Serratula tinctoria (Asteraceae), Betonica officinalis (Lamiaceae), Drosera intermedia (Droseraceae) and Lycopodiella inundata (Lycopodiaceae), occurring at one of two wetland sites (fen meadow and peat bog), which differed in soil pH and available P levels. Root colonization by arbuscular mycorrhizal fungi (AMF) and dark septate endophytes (DSE) was quantified. Colonization by AMF appeared to be more frequent in the fen meadow than in the peat bog, and depended on the host plant. Roots of S. tinctoria and B. officinalis were well colonized by AMF in the fen meadow (35-55% root length) and both arbuscules and vesicles were observed to occur in spring as well as in autumn. In the peat bog, L. inundata showed a low level of root colonization in spring, when vesicles were found frequently but no arbuscules. In roots of D. intermedia from the peat bog, arbuscules and vesicles were observed, but AMF colonization was lower than in L. inundata. In contrast, the amount of AMF spores extracted from soil at the peat bog site was higher than from the fen meadow soil. Spore numbers did not differ between spring and autumn in the fen meadow, but they were higher in spring than in autumn in the peat bog. Acaulospora laevis or A. colossica and Glomus etunicatum were identified amongst the AMF spores extracted from soil at the two sites. S. tinctoria and B. officinalis roots were also regularly colonized by DSE (18-40% root length), while L. inundata was only rarely colonized and D. intermedia did not seem to be colonized by DSE at all. PMID:15221579

  18. Ledere i aktion og udvikling

    DEFF Research Database (Denmark)

    Nielsen, Jens Carl Ry; Ry, Morten

    Denne artikel er et uddrag af endnu ikke publiceret bog om lederes hverdagsliv. Bogen bygger i meget høj grad på interviews. Vi har således interviewet 27 ledere to gange i perioden maj 2005 oktober 2006......Denne artikel er et uddrag af endnu ikke publiceret bog om lederes hverdagsliv. Bogen bygger i meget høj grad på interviews. Vi har således interviewet 27 ledere to gange i perioden maj 2005 oktober 2006...

  19. Diagenesis of sulphur in a peat forming environment: a case study from Sri Lanka

    Energy Technology Data Exchange (ETDEWEB)

    Senaratne, A.; Tobschall, H.J.; Dissanayake, C.B. (Universitaet Mainz, Mainz (Germany, F.R.). Inst. fuer Geowissenschaften)

    1990-03-01

    The sulphur geochemistry of the Muthurajawela peat deposit in Sri Lanka was studied. Due to the reducing conditions prevailing within the peat bog, sulphur was mainly in the sulphide form and almost all of the iron in the peat was in the form of iron sulphide. By releasing organically bound sulphur, the organic matter contributed significantly to the content of sulphur required for pyrite formation. It was found that the pyrite distribution in the peat bog did not depend on the depth of the organic matter, but on the state of decomposition. 20 refs., 7 figs., 1 tab.

  20. Modelling of Boil-Off Gas in LNG Tanks: A Case Study

    OpenAIRE

    Sheikh Zahidul Islam; Ebenezer Adom; Xianda Ji

    2010-01-01

    This paper focuses on the effect of pressure and heat leakages on Boil-off Gas (BOG) in Liquefied Natural Gas (LNG) tanks. The Lee-Kesler-Plocker (LKP) and the Starling modified Benedict-Webb-Rubin (BWRS) empirical models were used to simulate the compressibility factor, enthalpy and hence heat leakage at various pressures to determine the factors that affect the BOG in typical LNG tanks of different capacities. Using a case study data the heat leakage of 140,000kl, 160,00kl, 180,000kl and 20...

  1. Mellem tiderne - Fem dialektiske teologer

    DEFF Research Database (Denmark)

    I denne bog præsenteres Karl Barth, Friedrich Gogarten, Edu­ard Thurneysen, Emil Brunner og Rudolf Bultmann. Fem bidrag belyser deres teologiske anliggender, opgør og afgørelser, samt virkningshistorie og perspektiver for en nutidig teologi.......I denne bog præsenteres Karl Barth, Friedrich Gogarten, Edu­ard Thurneysen, Emil Brunner og Rudolf Bultmann. Fem bidrag belyser deres teologiske anliggender, opgør og afgørelser, samt virkningshistorie og perspektiver for en nutidig teologi....

  2. 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....

  3. Preliminary paleoecological reconstruction of long-term relationship between human and environment in the northern part of Danube-along Plain, Hungary

    Directory of Open Access Journals (Sweden)

    Kustár Rozália

    2016-06-01

    Full Text Available The peat bog at Ócsa is located at the northern part of the Danube-Tisa Interfluves at the transitional zone of two landscapes with different morphological characters. At the boundary of the Danube-Tisa Interfluves and the Danube-along Plain a marshland sequence can be found from Hajós to Ócsa. We extended our research to the Ócsa peat bog to complete the environmental historical investigations in the examined area, as well.

  4. 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....

  5. The Medieval Climate Anomaly and the Little Ice Age in the eastern Ecuadorian Andes

    OpenAIRE

    Ledru, M.-P.; Jomelli, V; Samaniego, P.; M. Vuille; S. Hidalgo; M. Herrera; Ceron, C.

    2013-01-01

    To better characterize the climate variability of the last millennium in the high Andes, we analyzed the pollen content of a 1150-yr-old sediment core collected in a bog located at 3800 m a.s.l. in the páramo in the eastern Cordillera in Ecuador. An upslope convective index based on the ratio between cloud transported pollen from the Andean forest to the bog (T) and Poaceae pollen frequencies, related to the edaphic moisture of the páramo (P), was defined. This index was use...

  6. 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....

  7. Flora

    DEFF Research Database (Denmark)

    Friis, Ib

    2010-01-01

    Flora var en romersk gudinde for blomstring og frugtbarhed. I overensstemmelse med renæssancens genbrug af antikke guder anvendte P.G.B. Ferrari i 1633 Floras navn på en bog om havebrug og Simon Pauli kaldte i 1648 en bog om danske nyttige planter for Flora Danica, begge med reference til den...... romerske blomstergudinde. Herfra spores ordet "flora" til det moderne brug som globalt anvendt betegnelse for en regionalt begrænset håndbog om planter....

  8. Indledning til Maple for Lineær Algebra

    DEFF Research Database (Denmark)

    Sinclair, Robert

    1999-01-01

    Denne rapport er en undersoegelse af hvordan og hvor vidt Maplesindbyggede kommandoer passer til Jens Eisings bog "Lineaer Algebra" (1997).Maalet er at beskrive, hvordan man bedst kan brugeMaple V Release 5.1i kurset,i viden om mulige problemer, saa man kan undgaa faelder,og svare paa studerendes...

  9. Jens Glebe-Møller: Struensees vej til skafottet. Fornuft og åbenbaring i Oplysningstiden, Museum Tusculanums Forlag, 2007, 134 s., kr. 148

    DEFF Research Database (Denmark)

    Olden-Jørgensen, Sebastian

    2008-01-01

    Den anmeldte bog bringer ikke nyt om Struensees vej til skafottet, men er en perspektivrig undersøgelse af Struensees sjælesørger, Balthasar Münterss neologiske teologi og sjælesorg i spændingsfeltet mellem religionskritisk fransk og religionsvenlig tysk oplysning....

  10. Litteratur er nyttig

    DEFF Research Database (Denmark)

    Kaspersen, Peter

    2012-01-01

    Den anmeldte bog er en forskningsbaseret debatbog om hvilken nytteværdi litteratur har. Bogen placeres i sammenhæng med en række bøger på nordiske sprog og engelsk om litteraturens, litteraturundervisningens og -forskningens legitimitet. Argumentatioen i bogen bygger på Bakhtins litteratursyn, og...

  11. Nuevas organizaciones en comunidades campesinas

    DEFF Research Database (Denmark)

    Pærregaard, Karsten

    Denne bog analyserer: 1) hvorledes to indianske landsbyer i Perus højland har reformeret ejendomsretten til jord og estableret landbrugskoorporativer og 2) hvorledes de to landsbyer deltager i to større landsbrugskollektiver. Bogen bygger på et års etnografisk feltarbejde i Peru fra 1983-84 og fo...

  12. Modelling evaporation from a drained and rewetted peatland

    NARCIS (Netherlands)

    Spieksma, JFM; Moors, EJ; Dolman, AJ; Schouwenaars, JM

    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 measu

  13. Sansning som redskab og metode for faget Modedesign

    DEFF Research Database (Denmark)

    Ræbild, Ulla

    2009-01-01

    åbne og neuropsykologen og pædagogen Howard Garners Multiples Intelligences. Herudover er Kvale/Brinkmanns fænomenologisk baserede bog InterView, om kvalitativ interviewpraksis i forskningsøjemed blevet anvendt i forbindelse med forberedelsen, udførelsen og bearbejdningen af det empiriske materiale...

  14. AMAMM - All Media Are Mixed Media

    DEFF Research Database (Denmark)

    All Media Are Mixed Media Alle medier er blandingsmedier. Alle kunstarter er kompositte. Alle sanser er sammensatte. Alle medialiteter er miksede og mangfoldige. Alle er AMAMM. Denne påstand står centralt i ord-, billed- og medie-teoretikeren W.J.T. Mitchells forfatterskab. I hosstående bog tager...

  15. Development of dangerous geological processes in the Hankaisky Region of Primorskiy Krai (Russian Far East)

    Institute of Scientific and Technical Information of China (English)

    Tatiana V. Selivanova

    2006-01-01

    Hankaisky Region is the most densely populated and economic developed part of the Primorskiy Krai. It is promoting development of dangerous geological processes there. In the article the reasons of formation and intensive development in Hankaisky Region of the following dangerous geological processes lateral, winder and ground erosive, sill, floods, taluses, bogging, slope wash, karts, rebound of ground are considered.

  16. Effect of soil properties and hydrology on Archaeal community composition in three temperate grasslands on peat

    DEFF Research Database (Denmark)

    Görres, Carolyn-Monika; Conrad, Ralf; Petersen, Søren O

    2013-01-01

    Grasslands established on drained peat soils are regarded as negligible methane (CH4) sources; however, they can still exhibit considerable soil CH4 dynamics. We investigated archaeal community composition in two different fen peat soils and one bog peat soil under permanent grassland in Denmark...

  17. Barbarians in the Norteh - the Greatest Concentration of Roman Weaponry in Europe

    DEFF Research Database (Denmark)

    Hansen, Ulla Lund

    2007-01-01

    Presentation and discussion af the great amount of weaponry in the Danish bogs and lakes dated to the Roman Iron Age (0-400 AD). The paper discuss the character of the weaponofferings, the Roman imported weaponry in the offerings, the influence at the Germanic weapons from the Roman army...

  18. Elementær Teori for Plane Bjælker

    DEFF Research Database (Denmark)

    Byskov, Esben

    Denne bog er skrevet med henblik på introduktion og benyttelse af de mest basale teorier for strenger og bjælker, hvor hovedvægten er lagt på retliniede, plane bjælker. Bogens indhold dækker mere end et enkelt semesters pensum ved bygningsingeniøruddannelsen ved Aalborg Universitet. Ideen er, at de...

  19. 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....

  20. 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 propert

  1. 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 bio

  2. Fra "en rigtig pige" til "en gravid mand"

    DEFF Research Database (Denmark)

    Heede, Dag

    2012-01-01

    Nedslag i to eksempler på "transreproduktion": Lili Elbe, en transkvinde, der i 1931 døde efter en række kønsskifteoperationer og Thomas Beatie, en transmand, der i 2008 fødte et barn udgav en bog om det....

  3. Oplysning på trods

    DEFF Research Database (Denmark)

    Petersen, Lars Axel

    Første bog på dansk om sociologen Karl Mannheim (1893-1947). Let revideret udgave af Ph.d.-afhandling udarbejdet ved Institut for Idéhistorie ved Aarhus Universitet. I bogen undersøges aktualiteten af Mannheims videnssociologi. Der skelnes mellem på den ene side aktualitet som en relation mellem ...

  4. 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...

  5. Kvantemekanik

    DEFF Research Database (Denmark)

    Mølmer, Klaus

    enorm succes, men fortolkningen af den splittede samtidig tidens største videnskabsmænd, særligt Niels Bohr og Albert Einstein. Denne bog gennemgår kvantemekanikkens og fysikkens udvikling i det 20. århundrede - og giver indblik i de nyeste opdagelser af, hvordan den atomare verden fungerer...

  6. Software og kvalitativ dataanalyse

    DEFF Research Database (Denmark)

    Kristiansen, Søren

    Denne bog handler om brug af softwareprogrammer til håndtering og analyse af kvalitative data. Den gengiver og diskuterer nogle af de væsentligste problemstillinger, muligheder og perspektiver, som knytter sig til indførelsen af softwareredskaber til analyse af kvalitative data med udgangspunkt i...

  7. 40 CFR 112.2 - Definitions.

    Science.gov (United States)

    2010-07-01

    ... legal designation or by evaluations of Area Committees (for planning) or members of the Federal On-Scene... either directly or indirectly from exposure to a discharge, or exposure to a product of reactions... life in saturated soil conditions. Wetlands generally include playa lakes, swamps, marshes, bogs,...

  8. Selecting parameters for the environmental interpretation of peat molecular chemistry - A pyrolysis-GC-MS study

    NARCIS (Netherlands)

    Schellekens, J.F.P.; Buurman, P.; Pontevedra Pombal, X.

    2009-01-01

    A number of samples from a deep peat bog in Tierra del Fuego were analyzed using pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) in order to extract parameters that might be used to interpret the peat chemistry in terms of vegetation change, anaerobic and aerobic decomposition, and fire in

  9. Dyp tæerne i skriftsproget!

    DEFF Research Database (Denmark)

    Korsgaard, Klara Aalbæk

    2012-01-01

    I denne bog argumenterer forskere og erfarne praktikere for, hvorfor det lille barn bør inviteres til at udforske og kommunikere via skriftsproget. Der bliver også lagt vægt på, hvordan skrivning kan indgå i børnehaven på en legende og støttende måde....

  10. Passionate Utterance and Moral Education

    Science.gov (United States)

    Munday, Ian

    2009-01-01

    This paper explores Stanley Cavell's notion of "passionate utterance", which acts as an extension of/departure from (we might read it as both) J. L. Austin's theory of the performative. Cavell argues that Austin having made the revolutionary discovery that truth claims in language are bound up with how words perform, then gets bogged by convention…

  11. De professionelle i velfærdsstaten

    DEFF Research Database (Denmark)

    Denne bog handler om de professionelle i den del af den offentlige sektor, der beskæftiger sig med serviceproduktion. Der er mange forskellige professioner, der beskæftiger sig med serviceproduktion i den offentlige sektor. De professioner man i første omgang tænker på er lærere, pædagoger, sygep...

  12. 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 ...

  13. Tundra in the rain

    DEFF Research Database (Denmark)

    Keuper, Frida; Parmentier, Frans-Jan; Blok, Daan;

    2012-01-01

    tundra (northeast Siberia) and a dry Sphagnum fuscum-dominated bog (northern Sweden). Positive responses to approximately doubled ambient precipitation (an increase of 200 mm year-1) were observed at the Siberian site, for B. nana (30 % larger length increments), Salix pulchra (leaf size and length...

  14. Computer Cache. Wildlife on the Web: Connections to Animals, Biomes, Environments, and Habitats

    Science.gov (United States)

    Byerly, Greg; Brodie, Carolyn S.

    2004-01-01

    Follow the migration of monarch butterflies, explore Yellowstone National Park, find out about endangered species in the Everglades, or learn about the wildlife dependent upon a bog for existence. This article describes how students can learn these things and many more through the numerous resources available on the World Wide Web that feature…

  15. Lærerprofiler i dansk - nye mål og kompetencer 1.-6. klassetrin 2

    DEFF Research Database (Denmark)

    Carlsen, Benny Bang; Mølgaard, Niels

    I denne anden bog i serien introduceres til de fire studiekompetenceområder, der knytter sig til undervisningen i folkeskolens 1.-6. klassetrin. Hvert kapitel præsenterer central forskningsbaseret viden inden for det pågældende tema, og der gives løbende eksempler på analytisk tekstarbejde, som på...

  16. Mathilde Prager - brobygger mellem Østrig og Norden

    DEFF Research Database (Denmark)

    Bang, Karin

    2004-01-01

    Den første nordiske forfatter, som den østrigske oversætter Mathilde Prager kom i forbindelse med, var nordmanden Jonas Lie, som hun oversatte to romaner af. Senere fik hun forbindelse med Arne Garborg og Knut Hamsun. Hun oversatte et værk af Clara Tschudi og skrev en omdiskuteret bog om Henrik...

  17. Lærerprofiler i dansk - Nye mål og kompetencer 4.-10.klassetrin 3

    DEFF Research Database (Denmark)

    Carlsen, Benny Bang; Mølgaard, Niels

    I denne tredje bog i serien introduceres til de fire studiekompetenceområder, der knytter sig til undervisningen i folkeskolens 4.-10. klassetrin. Hvert kapitel præsenterer central forskningsbaseret viden inden for det pågældende tema, og der gives løbende eksempler på analytisk tekstarbejde, som...

  18. En dronning kom til byen

    DEFF Research Database (Denmark)

    Storm, Rasmus K.

    2009-01-01

    Det er ganske rigtig et af dansk håndbolds mest dramatiske kapitler Dan Philipsen beskriver i sin bog om Anja Andersens eventyr i Slagelse: 'En dronning kom til byen'. Bogen er velskrevet, og er i sin form en velsignet god gang underholdning til natbordet. Problemet er bare, at man kan have svært...

  19. US moet nog ver vorder

    DEFF Research Database (Denmark)

    Bergenholtz, Henning

    2006-01-01

    Sprogpolitik består ikke udelukkende i valg af undervisningssprog, heller ikke på et universitet. Når rektor på universitetet i Stellenbosch, Chris Brink, i sin nye bog, The taaldebat at Stellenbosch, kun diskuterer undervisningssproget, foreligger der en så stor grad af forenkling, at en stor de...

  20. Review of Paul R. Hinlicky: Luther and the Beloved Community. A Path for Christian Theology after Christendom. Eerdmans 2010

    DEFF Research Database (Denmark)

    Pedersen, Else Marie Wiberg

    2011-01-01

    Denne anmeldelse er en kritisk gennemgang af Paul Hinlickys bog om luthersk teologi. Hinlicky ønsker at tilpasse Luther til katolsk teologi i form at det, han benævner "det nye Rom", og for at gøre dette benytter han sig af nogle problematiske hermeneutiske og metodologiske greb. Bogen handler så...

  1. Det frivillige Danmark

    DEFF Research Database (Denmark)

    Boje, Thomas P.

    Der er store forventninger til den frivillige sektors rolle for velfærden og demokratiet i Danmark. Denne bog giver svar på en række af de spørgsmål, som i den forbindelse er rejst: - Hvem er det, som engagerer sig i frivilligt arbejde? - Hvorfor er de etniske minoriteter mindre aktive i frivilli...

  2. Innovation systems as patent networks: the Netherlands, India and nanotech

    NARCIS (Netherlands)

    W. Dolfsma; L. Leydesdorff

    2011-01-01

    Research in the domain of 'Innovation Studies' has been claimed to allow for the study of how technology will develop in the future. Some suggest that the National and Sectoral Innovation Systems literature has become bogged down, however, into case studies of how specific institutions affect innova

  3. Innovation systems as patent networks : The Netherlands, India and nanotech

    NARCIS (Netherlands)

    Dolfsma, Wilfred; Leydesdorff, Loet

    2011-01-01

    Research in the domain of 'Innovation Studies' has been claimed to allow for the study of how technology will develop in the future. Some suggest that the National and Sectoral Innovation Systems literature has become bogged down, however, into case studies of how specific institutions affect innova

  4. Nanoteknologiske Horisonter

    DEFF Research Database (Denmark)

    Nanoteknologi er en relativt ny tværfaglig forskningsdisciplin, der forventes at få stor økonomisk og teknologisk betydning for vores samfund. ‘Nanoteknologiske Horisonter’ er en bog om nanoteknologi skrevet til elever og lærere ved gymnasieuddannelserne samt andre interesserede. Bogen gennemgår ...

  5. Konventionen von Fachtextsorten

    DEFF Research Database (Denmark)

    Engberg, Jan

    Emnet for denne bog er faste vendinger i den juridiske sprogbrug, som er karakteristiske for genren "landsretsdom". Til at undersøge denne genstand udvikler forfatteren et tekstlingvistisk analyseapparat, som er specielt tilpasset landsretsdomme som en stærkt standardiseret tekstgenre. Den egentl...... bogen slutter med en diskussion af forskellige måder at gengive de faste vendinger på....

  6. Ejeraftaler

    DEFF Research Database (Denmark)

    Kruhl, Martin Christian

    Denne bog er den første samlede og dybdegående afhandling om ejeraftaler på dansk. Ejeraftaler (tidligere 'aktionær- eller anpartsoverenskomster') spiller i praksis en væsentlig rolle som det aftalemæssige grundlag for de indbyrdes rettigheder og forpligtelser mellem kapitalejere i små og mellems...

  7. Temperature Responses to Infrared-Loading and Water Table Manipulations in Peatland Mesocosms

    Institute of Scientific and Technical Information of China (English)

    Jiquan Chen; Scott Bridgham; Jason Keller; John Pastor; Asko Noormets1and; F. Weltzin

    2008-01-01

    We initiated a multi-factor global change experiment to explore the effects of infrared heat loading (HT) and water table level (WL) treatment on soil temperature (T) in bog and fen peatland mesocosms. We found that the temperature varied highly by year, month, peatland type, soil depth, HT and WL manipulations. The highest effect of HT on the temperature at 25 cm depth was found in June for the bog mesocosms (3.34-4.27℃) but in May for the fen mesocosms (2.32-4.33℃) over the 2-year study period. The effects of WL in the bog mesocosms were only found between August and January, with the wet mesocosms warmer than the dry mesocosms by 0.48-2.03 ℃ over the 2-year study period. In contrast, wetter fen mesocoams were generally cooler by 0.16-3.87℃. Seasonal changes of temperatures elevated by the HT also varied by depth and ecosystem type, with temperature differences at 5 cm and 10 cm depth showing smaller seasonal fluctuations than those at 25 cm and 40 cm in the bog mesocosrns. However, increased HT did not always lead to warmer soil, especially in the fen mesocosms. Both HT and WL manipulations have also changed the length of the non-frozen season.

  8. Ensenanza basada en el diálogo

    DEFF Research Database (Denmark)

    Bernhardt, Nana; Dysthe, Olga; Esbjørn, Line

    Hvad er dialogbaseret undervisning, og hvordan kan den udfolde sig på et kunstmuseum? I denne bog viser forfatterne, hvordan erfarne museumsundervisere møder børn og unge på syv museer og udfordrer dem til nysgerrigt og kreativt at udforske temaer, udveksle synspunkter og udvikle nye tanker og id...

  9. Velkommen til gældens hus

    DEFF Research Database (Denmark)

    Lunde, Jens

    2015-01-01

    De amerikanske professorer, Atif Mian og Amir Sufi, udgav i år den udmærkede og noget oversete bog »House of Debt«, der vender fortællingen om finanskrisen på hovedet. Anmeldelse af: Atif Mian og Amir Sufi: "House of Debt. How They (and You) Caused the Great Recession, and How We Can Prevent...

  10. MATLAB syntaksen

    DEFF Research Database (Denmark)

    Skajaa, Anders; Jørgensen, Jakob Heide

    MATLAB er et matematik-program som fokuserer på anvendelsen af matricer og vektorer. Deraf navnet MATrix LABoratory. Denne bog er en praktisk vejledning i at forstår og anvende MATLAB syntaksen og fungerer som en hurtig genvej til dig, der skal i gang med at anvende MATLAB i forbindelse med fx dit...

  11. Paludisphaera borealis

    NARCIS (Netherlands)

    Kulichevskaya, I.S.; Ivanova, A.; Suzina, N.E.; Rijpstra, W.I.C.; Sinninghe Damsté, J.S.; Dedysh, S.N.

    2016-01-01

    Two isolates of aerobic, budding, pink-pigmented bacteria, designated strains PX4T and PT1, were isolated from a boreal Sphagnum peat bog and a forested tundra wetland. Cells of these strains were non-motile spheres that occurred singly or in short chains. Novel isolates were capable of growth at pH

  12. Mineral resource of the month: peat

    Science.gov (United States)

    Jasinski, Stephen M.

    2008-01-01

    Peat is a natural organic material of botanical origin, harvested from deposits in bogs and fens. Commercial deposits form from the incomplete decomposition of plant matter under anaerobic conditions and gradually accumulate to form peat over about a 5,000-year period.

  13. Climate and peat type in relation to spatial variation of the peatland carbon mass in the Hudson Bay Lowlands, Canada

    Science.gov (United States)

    Packalen, Maara S.; Finkelstein, Sarah A.; McLaughlin, James W.

    2016-04-01

    Northern peatlands store ~500 Pg of carbon (C); however, controls on the spatial distribution of the stored C may differ regionally, owing to the complex interaction among climate, ecosystem processes, and geophysical controls. As a globally significant C sink, elucidation of controls on the distribution of C in the Hudson Bay Lowlands, Canada (HBL), is of particular importance. Although peat age is related to timing of land emergence and peat depth in the HBL, considerable variation in the total C mass (kg m-2) among sites of similar peat age suggests that other factors may explain spatial patterns in C storage (Pg) and sequestration. Here we quantify the role of two key factors in explaining the spatial distribution of the C mass in the HBL (n = 364 sites), (i) climate variability and (ii) peat lithology, for two major peatland classes in the HBL (bogs and fens). We find that temperature, precipitation, and evapotranspiration each explained nearly half of the C mass variability. Regions characterized by warmer and wetter conditions stored the most C as peat. Our results show that bogs and fens store similar amounts of C within a given climate domain, although via distinct storage mechanisms. Namely, fen peats tend to be shallower and more C dense (kg m-3) compared to bogs. Following geophysical controls on the timing of peat initiation, our results reveal that both the widespread bog-fen patterning and variability in regional climate contribute to explaining the spatial distribution of the peat C mass in the HBL.

  14. 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 preservati...

  15. The future of innovation serves humanity before economy

    DEFF Research Database (Denmark)

    Darsø, Lotte

    2009-01-01

    En bog med over 200 globale bidragsydere om fremtiden for innovation. Vægten i Lotte Darsøs bidrag er på den menneskelige faktor som det væsentligste omdrejningspunkt for innovation samt på menneskelige værdier, læring og ledelse som vejen til innovation. www.thefutureofinnovation.org  ...

  16. Boganmeldelse - Music Therapy Research

    DEFF Research Database (Denmark)

    Ridder, Hanne Mette Ochsner

    2006-01-01

    . Alligevel følger her en anbefaling af bogen: for musikterapeuter er det en bog, man ikke kommer uden om. Music Therapy Research, på dansk Musikterapiforskning, er en gennemrevideret, ja faktisk nyudgivelse, af bogen Music Therapy Research: Quantitative and Qualitative Perspectives, som udkom i 1995. Også...

  17. Politisk Psykologi

    DEFF Research Database (Denmark)

    Karnøe, Jonatan Kolding

    Politisk psykologi er feltet mellem psykologi og samfundsfag. Hovedspørgsmålet i min bog er: Hvor kommer holdninger fra? Holdninger er dog mere end blot et individuelt anliggende. Der er mange aktører som påvirker – politiske ledere, store grupper eller medierne. Bogen vil her give hver part sit...

  18. 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...

  19. Læringsmiljø på hhx

    DEFF Research Database (Denmark)

    Vestergaard, Arnt Louw; Brown, Rikke; Simonsen, Birgitte

    Denne bog præsenterer resultaterne fra forskningsprojektet: Læringsmiljø på hhx - kvaliteter og udfordringer (2008-2010), som Center for Ungdomsforskning, DPU / AU har foretaget i samarbejde med Danske Erhvervsskoler - Lederne, støttet af undervisningsministeriet, Foreningen af Unge Handelsmænds ...

  20. 40 CFR 116.3 - Definitions.

    Science.gov (United States)

    2010-07-01

    ... as given below: The Act means the Federal Water Pollution Control Act, as amended by the Federal Water Pollution Control Act Amendments of 1972 (Pub. L. 92-500), and as further amended by the Clean... saturated soil conditions. Wetlands generally include swamps, marshes, bogs and similar areas; the...

  1. Elevated atmospheric CO2 and increased nitrogen deposition : effects on C and N metabolism and growth of the peat moss Sphagnum recurvum P. Beauv. var. mucronatum (Russ.) Warnst

    NARCIS (Netherlands)

    Van Der Heijden, E; Verbeek, SK; Kuiper, PJC

    2000-01-01

    Sphagnum bogs play an important role when considering the impacts of global change on global carbon and nitrogen cycles. Sphagnum recurvum P. Beauv. var. mucronatum (Russ.) was grown at 360 (ambient) and 700 mu L L-1 (elevated) atmospheric [CO2] in combination with different nitrogen deposition rate

  2. The acclimation of carnivorous round-leaved sundew (Drosera rotundifolia L.) to solar radiation

    NARCIS (Netherlands)

    Tkalec, Mirta; Doboš, Marko; Babić, Marija; Jurak, Edita

    2015-01-01

    Round-leaved sundew (Drosera rotundifolia L.) is a carnivorous plant which inhabits nutrient-poor, moist, and sun-exposed areas such as peat bogs and sandpits. These habitats are threatened by succession which could lead to substantial shading of sundews. Nevertheless, D. rotundifolia can also gr

  3. Persondataloven

    DEFF Research Database (Denmark)

    Høilund, Dorte Lissie

    Persondataloven regulerer behandling af oplysninger om borgerne og gælder både for offentlige myndigheder, private virksomheder, foreninger, organisationer mv. Denne bog giver en grundig og overskuelig introduktion til de centrale bestemmelser i persondataloven og sætter fokus på emner som...... behandling af personoplysninger, borgerens rettigheder og beskyttelse af personoplysninger....

  4. I bad med Picasso

    DEFF Research Database (Denmark)

    Tanggaard, Lene; Stadil, Christian Nicolas

    Alle er kreative! I denne bog viser Lene Tanggaard (professor i kreativitet) og Christian N. Stadil (ejer af bl.a. Hummel), at alle kan blive endnu mere kreative. De har interviewet en række af Danmarks mest kreative mennesker, for at finde ud af, hvordan de gør. Picasso gik i bad, når han skulle...

  5. Krigspolitik(k)en under angreb

    DEFF Research Database (Denmark)

    Villaume, Poul

    2008-01-01

    I de sidste 17-18 år har dansk udenrigs- og sikkerhedspolitik undergået en markant militarisering, med Danmarks aktive deltagelse i krigene i Afghanistan og Irak som hidtidige højdepunkter. Den anmeldte bog, Jørgen Bonde Jensens "Politiken og krigspolitikken. Et læserbrev", gennemgår kritisk dagb...

  6. Formativ Feedback

    DEFF Research Database (Denmark)

    Hyldahl, Kirsten Kofod

    Denne bog undersøger, hvordan lærere kan anvende feedback til at forbedre undervisningen i klasselokalet. I denne sammenhæng har John Hattie, professor ved Melbourne Universitet, udviklet en model for feedback, hvilken er baseret på synteser af meta-analyser. I 2009 udgav han bogen "Visible...

  7. Recent pollen spectra from the deciduous and coniferous-deciduous forests of Northeastern Minnesota: a study in pollen dispersal

    NARCIS (Netherlands)

    Janssen, C.R.

    1966-01-01

    Pollen samples were taken along nine transects across local vegetational belts bordering bogs or ponds in overall deciduous and coniferous-deciduous forest regions. Three types of pollen rain are distinguished: local, extralocal, and regional. Local pollen rain is derived from plants that grow at or

  8. Humanismens grænser

    DEFF Research Database (Denmark)

    Simonsen, Karen Margrethe

    2008-01-01

    Artiklen handler om opfattelser af lov og straf i Steen Steensen Blichers fortælling "Præsten i Vejlbye". Der tages udgangspunkt bla. i Peter Brooks' bog om falske tilståelser ("Troubling Confessions" fra 2000) og herudfra analyseres både præstens og herredsfogedens bekendelser....

  9. Narrative Normativity in Diasporic Jeremiah-and Today

    DEFF Research Database (Denmark)

    Holt, Else Kragelund

    2011-01-01

    Jeremias' bog kan betragtes som et redskab til at give normative svar i den kaotiske politisk/national/religiøse situation, som eksiltiden udgjorde. Artiklen undersøger, hvordan denne normativitet formidles gennem såvel prosa som poetiske dele af bogen og rejser afsluttende spørgsmålet, om den ko...

  10. Systemteori og didaktik

    DEFF Research Database (Denmark)

    Keiding, Tina Bering; Qvortrup, Ane

    Didaktikbegrebet har i de senere år spredt sig fra grundskoleområdet til hele uddannelsesfeltet, fra børnehaven over gymnasiet til de videregående uddannelser. Denne bog præsenterer didaktikken i en systemteoretisk belysning. Systemteorien indbyder til nye perspektiver på undervisning og læring o...

  11. Law & Religion in the 21st Century

    DEFF Research Database (Denmark)

    En nordisk bog om forholdet mellem stat, kirker og trossamfund; mellem religion og ret; mellem flertal og mindretalsreligioner i det post-sekulære og post-lutherske Norden. Bogen påviser, hvor og hvordan de nordiske modeller har behov for at blive justeret. Men det fremgår også klart, at nordiske...

  12. Thin book

    DEFF Research Database (Denmark)

    En lille bog om teater og organisationer, med bidrag fra 19 teoretikere og praktikere, der deltog i en "Thin Book Summit" i Danmark i 2005. Bogen bidrager med en state-of-the-art antologi om forskellige former for samarbejde imellem teater og organisationer. Bogen fokuserer både på muligheder og...

  13. 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...

  14. Storfyrstinde Olga i eksil

    DEFF Research Database (Denmark)

    Frederichsen, Kim; Fledelius, Karsten; Krag, Anne Hedeager

    Bog om Storfyrstinde Olga, der var søster til den sidste zar, Nikolaj II, og datter af kejserinde Dagmar og zar Aleksandr III. Bogen omhandler Olgas dramatiske liv , herunder flugten til Danmark efter det bolsjevistiske statskup i 1917 og den videre flugt til Canada efter Anden Verdenskrig med...

  15. Projektpædagogik

    DEFF Research Database (Denmark)

    Projektarbejdet og den problembaserede læring er den bærende pædagogiske model for Aalborg Universitets uddannelser og har været det siden universitetets start i 1974. Denne bog rummer seks bidrag til forståelsen af projektpædagogikkens teori og praksis, skrevet af forskere, som repræsenterer for...

  16. Fundamentals,Confidence and Policy

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    @@ Entering the third year of the most serious economic crisis since the Great Deprerssion,the world economy is still bogged down on the muddy road to recovery.The latest edition of Standard Chartered Bank's monthly report,Global Focus,published on February 2,offered some analysis on the outlook of the global economy this year.

  17. Controls on CH4 flux from an Alaskan boreal wetland

    Science.gov (United States)

    Moosavi, Sadredin C.; Crill, Patrick M.; Pullman, Erik R.; Funk, Dale W.; Peterson, Kim M.

    1996-06-01

    Factors controlling the flux of the radiatively important trace gas methane (CH4) from boreal wetlands were examined at three sites along a moisture gradient from a treed low-shrub bog to an open floating graminoid bog in Fairbanks, Alaska. In the summer of 1992 average static chamber flux measurements were -0.02, 71.5, and 289 mg CH4/m2/d in dry, wet, and floating mat communities, respectively. In contrast, the warmer, drier 1993 field season flux measurements were -0.02, 42.9 and 407 mg CH4/m2/d. The data indicate that despite net oxidation of CH4 in the dry regions of the bog, the wetland is a net source of CH4, with fluxes ranging across three orders of magnitude between different plant communities. Comparison with water levels suggests that CH4 flux is turned on and off by changes in site hydrology. In sites where sufficient moisture is present for methanogenesis to occur, CH4 flux appears to be temperature limited, responding exponentially to soil temperature changes. The combined effects of hydrology and temperature create hot spots of CH4 flux within boreal wetlands. The plant communities within Lemeta Bog respond differently to changes in temperature and moisture availability, creating both positive and negative feedbacks to potential global climate change.

  18. 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...

  19. Nu har dagplejen en fælles historie

    DEFF Research Database (Denmark)

    Dybbroe, Betina

    2006-01-01

    Igennem aktionsforskningsprojekt i samarbejde med et uddannelsesprojekt i den Bornholmske dagpleje blev skabt ny viden om læring i fællesskaber i arbejdslivet for kortuddannede og mellemuddannede kvinder med omsorgsarbejde. Bidraget er en del af en bog ,som var et af flere resultater af et EU soc...

  20. Otter Lutra lutra Predating Dragonflies

    Directory of Open Access Journals (Sweden)

    Bailley M.P.

    2000-10-01

    Full Text Available In June 2000, the author found spraints and other signs indicating that at least one otter had been eating quantities of adult Four-Spotted Chasers (Libellula quadrimaculata common at the location, on the coastal raised bog of Cors Fochno in west Wales.

  1. Otter Lutra lutra Predating Dragonflies

    OpenAIRE

    Bailley M.P.

    2000-01-01

    In June 2000, the author found spraints and other signs indicating that at least one otter had been eating quantities of adult Four-Spotted Chasers (Libellula quadrimaculata) common at the location, on the coastal raised bog of Cors Fochno in west Wales.

  2. 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

  3. 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 extrem

  4. 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...

  5. Application of GIS and logistic regression to fossil pollen data in modelling present and past spatial distribution of the Colombian savanna

    NARCIS (Netherlands)

    S.G.A. Flantua; J.H. van Boxel; H. Hooghiemstra; J. van Smaalen

    2007-01-01

    Climate changes affect the abundance, geographic extent, and floral composition of vegetation, which are reflected in the pollen rain. Sediment cores taken from lakes and peat bogs can be analysed for their pollen content. The fossil pollen records provide information on the temporal changes in clim

  6. The use of Tithonian oolitic limestones from the Lorraine especially Morley, in construction and restoration in the Netherlands, 1840-1960

    NARCIS (Netherlands)

    2015-01-01

    The Netherlands have only limited resources of dimension stone within the own borders, viz. local bog iron ore in the middle and east of the country, erratics from the Saalian ice age used in a few churches in the north, and Carboniferous sandstone and Cretaceous limestones in the south of Limburg (

  7. Strategisk ledelse - tilbage til basis - og videre!

    DEFF Research Database (Denmark)

    Drejer, Anders

    2003-01-01

    kulturen i de nye forretninger, som skabes. Den direkte anledning til den herværende artikel er forfatterens bog - Strategic Management and Core Competencies - som i sommeren 2002 blev udgivet på det amerikanske forelag Quorum og som indeholder en række overvejelser om hvordan fagområdet strategisk ledelse...

  8. СОСТОЯНИЕ РАСТИТЕЛЬНОСТИ НА ПЕРЕХОДНЫХ БОЛОТАХ ЗАПАДНОЙ СИБИРИ ПРИ НЕФТЯНОМ ЗАГРЯЗНЕНИИ

    OpenAIRE

    СЕРИКОВА Е.С.; КАЗАНЦЕВА М.Н.

    2010-01-01

    It is shown that oil pollution of transitive bogs makes negative impact on a condition of all components phutocoenosis: leads to oppression and destruction of plants, to decrease in efficiency living soil-cover, to redistribution in it to a role of separate groups of plants. The size of negative changes is directly proportional intensity of oil pollution.

  9. Freshwater Wetlands.

    Science.gov (United States)

    Naturescope, 1986

    1986-01-01

    Provides descriptions about freshwater wetlands, such as marshes, swamps, and bogs. Contains three learning activities which deal with unusual wetland plants, the animals and plants in a typical marsh, and the effects of a draught on a swamp. Included are reproducible handouts and worksheets for two of the activities. (TW)

  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. Hydrologic controls on DOC, As and Pb export from a polluted peatland – the importance of heavy rain events, antecedent moisture conditions and hydrological connectivity

    Directory of Open Access Journals (Sweden)

    T. Broder

    2015-03-01

    Full Text Available Bogs can store large amounts of lead (Pb and arsenic (As attributed to atmospheric deposition of anthropogenic emissions. Pb and As are exported along with dissolved organic carbon (DOC in these organic-rich systems, but it is not yet clear which hydrological (pre-conditions favor their export. This study combines one year continuous monitoring of precipitation, bog water level and pore water concentration changes with bog discharge, DOC, As and Pb stream concentrations and fluxes. 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 by the upper 10% of discharge, pointing out the over-proportional contribution of heavy rain and 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 of the soluble Pb pool as soon as the peat layer gets hydrologically connected, while DOC and As peak concentrations in runoff lag in comparison to Pb. Our data indicates 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 concentration do not further increase and discharge gets diluted. Combining pore water and discharge data shows that As and Pb exports are not only dependent on the amount of precipitation and discharge, but 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 mobilized than Pb, with annual fluxes accounting for 0.85 and

  12. Recent atmospheric Pb deposition at a rural site in southern Germany assessed using a peat core and snowpack, and comparison with other archives

    Science.gov (United States)

    Le Roux, Gaël; Aubert, Dominique; Stille, Peter; Krachler, Michael; Kober, Bernd; Cheburkin, Andriy; Bonani, Georges; Shotyk, William

    In a peat bog from Black Forest, Southern Germany, the rate of atmospheric Pb accumulation was quantified using a peat core dated by 210Pb and 14C. The most recent Pb accumulation rate (2.5 mg m -2 y -1) is similar to that obtained from a snowpack on the bog surface, which was sampled during the winter 2002 (1 to 4 mg m -2 y -1). The Pb accumulation rates recorded by the peat during the last 25 yr are also in agreement with published values of direct atmospheric fluxes in Black Forest. These values are 50 to 200 times greater than the "natural" average background rate of atmospheric Pb accumulation (20 μg m -2 y -1) obtained using peat samples from the same bog dating from 3300 to 1300 cal. yr B.C. The isotopic composition of Pb was measured in both the modern and ancient peat samples as well as in the snow samples, and clearly shows that recent inputs are dominated by anthropogenic Pb. The chronology and isotopic composition of atmospheric Pb accumulation recorded by the peat from the Black Forest is similar to the chronologies reported earlier using peat cores from various peat bogs as well as herbarium samples of Sphagnum and point to a common Pb source to the region for the past 150 years. In contrast, Pb contamination occurring before 1850 in southwestern Germany, differs from the record published for Switzerland mainly due to the mining activity in Black Forest. Taken together, the results show that peat cores from ombrotrophic bogs can yield accurate records of atmospheric Pb deposition, provided that the cores are carefully collected, handled, prepared, and analysed using appropriate methods.

  13. 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

  14. The Relative Importance of Methanogenesis in the Decomposition of Organic Matter in Northern Peatlands

    Science.gov (United States)

    Corbett, J. Elizabeth; Tfaily, Malak M.; Burdige, David J.; Glaser, Paul H.; Chanton, Jeffrey P.

    2015-01-01

    Using an isotope-mass balance approach and assuming the equimolar production of CO2 and CH4 from methanogenesis (e.g., anaerobic decomposition of cellulose), we calculate that the proportion of total CO2 production from methanogenesis varies from 37 to 83% across a variety of northern peatlands. In a relative sense, methanogenesis was a more important pathway for decomposition in bogs (80 +/- 13% of CO2 production) than in fens (64 +/- 5.7% of CO2 production), but because fens contain more labile substrates they may support higher CH4 production overall. The concentration of CO2 produced from methanogenesis (CO2-meth) can be considered equivalent to CH4 concentration before loss due to ebullition, plant-mediated transport, or diffusion. Bogs produced slightly less CO2-meth than fens (2.9 +/- 1.3 and 3.7 +/- 1.4 mmol/L, respectively). Comparing the quantity of CH4 present to CO2-meth, fens lost slightly more CH4 than bogs (89 +/- 2.8% and 82 +/- 5.3%, respectively) likely due to the presence of vascular plant roots. In collapsed permafrost wetlands, bog moats produced half the amount of CO2-meth (0.8 +/- 0.2mmol/L) relative to midbogs (1.6 +/- 0.6 mmol/L) and methanogenesis was less important (42 +/- 6.6% of total CO2 production relative to 55 +/- 8.1%).We hypothesize that the lower methane production potential in collapsed permafrost wetlands occurs because recently thawed organic substrates are being first exposed to the initial phases of anaerobic decomposition following collapse and flooding. Bog moats lost a comparable amount of CH4 as midbogs (63 +/- 7.0% and 64 +/- 9.3%).

  15. Representing northern peatland microtopography and hydrology within the Community Land Model

    Directory of Open Access Journals (Sweden)

    X. Shi

    2015-02-01

    Full Text Available Predictive understanding of northern peatland hydrology is a necessary precursor to understanding the fate of massive carbon stores in these systems under the influence of present and future climate change. Current models have begun to address microtopographic controls on peatland hydrology, but none have included a prognostic calculation of peatland water table depth for a vegetated wetland, independent of prescribed regional water tables. We introduce here a new configuration of the Community Land Model (CLM which includes a fully prognostic water table calculation for a vegetated peatland. Our structural and process changes to CLM focus on modifications needed to represent the hydrologic cycle of bogs environment with perched water tables, as well as distinct hydrologic dynamics and vegetation communities of the raised hummock and sunken hollow microtopography characteristic of peatland bogs. The modified model was parameterized and independently evaluated against observations from an ombrotrophic raised-dome bog in northern Minnesota (S1-Bog, the site for the Spruce and Peatland Responses Under Climatic and Environmental Change experiment (SPRUCE. Simulated water table levels compared well with site-level observations. The new model predicts significant hydrologic changes in response to planned warming at the SPRUCE site. At present, standing water is commonly observed in bog hollows after large rainfall events during the growing season, but simulations suggest a sharp decrease in water table levels due to increased evapotranspiration under the most extreme warming level, nearly eliminating the occurrence of standing water in the growing season. Simulated soil energy balance was strongly influenced by reduced winter snowpack under warming simulations, with the warming influence on soil temperature partly offset by the loss of insulating snowpack in early and late winter. The new model provides improved predictive capacity for seasonal

  16. 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.

  17. Understanding Carbon Storage in Permafrost Peatlands: Examples from Thermokarst Landscapes in Interior Alaska

    Science.gov (United States)

    Jones, M.; Harden, J. W.; O'Donnell, J. A.; Manies, K.; Jorgenson, T.

    2014-12-01

    As the climate at high latitudes continues to warm, permafrost is becoming increasingly vulnerable to thaw, particularly in the zone of discontinuous permafrost where mean annual air temperatures hover close to zero. Permafrost thaw has dramatic consequences on local hydrology, ecology, and the carbon (C) balance of these ecosystems. The degree to which permafrost peatlands become C sources or sinks following permafrost thaw remains a topic of much debate, owing to the difficulty in accurately dating cores from collapse-scar bogs and in understanding the vulnerability of the formerly forested peat to decomposition immediately following thaw and inundation. Here we use a combination of a chronosequence, paleoenvironmental, and modeling approaches from a permafrost peat plateau interspersed with collapse-scar bogs in Interior Alaska to address how C storage is impacted on timescales from decades to millennia following permafrost thaw. Our initial results indicate that C stocks are lowest in young (years to decades) and intermediate (decades to centuries) collapse-scar bogs, but that net C stocks in old (centuries to millennia) bogs can be as high as in permafrost plateaus. Thawed forested plateau peat is subject to rapid decomposition in the years to decades following thaw, but that rate of loss slows over time. We hypothesize that this is because the labile C pool is preferentially consumed and quickly exhausted by soil microbes. Meanwhile, post-thaw collapse-scar bog peat accumulates rapidly at the surface, and our data show that on longer centennial to millennial timescales, this near-surface C may offset initial post-thaw losses at depth. Collapse-scar bog peat accumulation rates outpace the former-plateau peat loss in a matter of years to decades. Older landscapes (i.e., those that began accumulating peat many thousands of years ago), are subject to greater C loss following thaw than are younger landscapes(i.e., those that initiated only a couple thousand years

  18. 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?...

  19. Environmental aspects of alternative wet technologies for producing energy/fuel from peat. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Smith, R.T.

    1981-05-01

    Peat in situ contains up to 90% moisture, with about 50% of this moisture trapped as a colloidal gel. This colloidal moisture cannot be removed by conventional dewatering methods (filter presses, etc.) and must be removed by thermal drying, solvent extraction, or solar drying before the peat can be utilized as a fuel feedstock for direct combustion or gasification. To circumvent the drying problem, alternative technologies such as wet oxidation, wet carbonization, and biogasification are possible for producing energy or enhanced fuel from peat. This report describes these three alternative technologies, calculates material balances for given raw peat feed rates of 1000 tph, and evaluates the environmental consequences of all process effluent discharges. Wastewater discharges represent the most significant effluent due to the relatively large quantities of water removed during processing. Treated process water returned to the harvested bog may force in situ, acidic bog water into recieving streams, disrupting local aquatic ecosystems.

  20. Uranium and radioactivity in Swedish peatlands

    International Nuclear Information System (INIS)

    Less than 10% of the peatlands in Sweden siutable for peat production have a increased content of uranium (more than 200 ppm) ash. The highest uranium content is normally found on the edges and at the bottom of the bogs, i.e. parts which normally are laft out during peat cutting. In some isolated cases high radioactivity can be found in the upper decimeters of the bogs. Thorium content in peat ashes is always low (less than 150 ppm ashsubstance). Increased contents occurs only when the peat is in contact with ground water. Simple and approved methods for the determination of thorium and uranium levels in fuel peat land exists already. There is no equilibrium on decay between radium 226 and uranium 238 in peatlands and accordingly no simple relationship exists between uranium and radiation on peatlands. Analysis at the prospecting stage ought not only be made on uranium and thorium, but also on other radionuclides. (BoK)

  1. Microelements in Lowland Peat of the Northeastern Part of the Altai Mountains

    Science.gov (United States)

    Shurova, M. V.; Larina, G. V.; Kozlova, S. A.; Shagaeva, L. L.

    2010-05-01

    The greatest areas of bogs are concentrated in the northeastern part of Altai Republic. This place due to a great amount of precipitation and a powerful accumulation of snow with a little drain in comparison with other areas has plenty of bogs. A quarter of all bogs of the Altai Mountains is concentrated here. The bogs develop mainly in the valleys of the rivers. The bogs have a modern origin and the process of bog formation goes at the present time by overgrowing of oxbow and valley lakes, and also by bogging of dry lands - woods and meadows. The area of bogs in relation to the general territory of highlands makes up 1%. Nevertheless, these territories are regarded as complex ecosystems which have economic and scientific value. Let's consider the content of heavy metals in different horizons of the peat under study. The samples of peat of the deposit being examined are characterized by a low total content of zinc: 6,21-44,12 mg/kg. The average amount of zinc in the soils of the Altai Mountains is much larger and makes up 70,3 mg/kg. Quite a significant amount of copper is washed away from peat thickness, its total amount is at the level of 1,58-10,73 mg/kg. The reason for it, probably, lies in the fact that there is a significant amount of fulvic acids in the composition of humic acids which enable the migration of copper beyond the limits of the peat ground in the conditions of the sour environment. A completely different situation is observed in the soils of the Altai mountain area. The biogeochemistry of copper in the soils of the Altai Mountains is thoroughly investigated by M.A.Malgin, A.V.Puzanov, O.A.Yelchininova. Its average amount in the soils of the Altai Mountains makes up 40,6 mg/kg which is twice as much as the abundance ratio in comparison with the world soils. The authors explain this fact as follows: copper is an inactive element in the soils since its ions are easily precipitated by sulfide-, carbonate-, and hydroxide ions, and also are taken up

  2. Recent changes in vegetation, hydrotopography and peat accumulation in detailed case studies of northern aapa mires

    Science.gov (United States)

    Tahvanainen, Teemu; Kumpula, Timo; Tolonen, Kimmo

    2016-04-01

    Aapa mires are northern mire complexes with typical patterned central fen areas and relatively thin peat layers. In principle, aapa mires could develop into raised bogs either 1) through autogenic succession, given enough time for peat accumulation or 2) through allogenic mechanism triggered by hydrological change. Climate change models predict that the climatic envelop of aapa mires will move north and, indeed, that hydrology may change sufficiently to cause allogenic change pressure. Potential resilience or pace of ecosystem-scale responses are poorly understood, however, in the case of aapa mires. We studied recent (ca. 60 years) changes in vegetation, hydrotopography and peat accumulation of two aapa mires at their southern limit of distribution in eastern Finland. We used repeated sampling after 60 years combined with peat stratigraphy and time-series of aerial images in a multi-proxy approach. The study site at the Valkeasuo mire was affected by extensive drainage activities in its catchment, while the aapa mire area itself was not drained. This resulted in the loss of minerotrophic hydrology that lead to rapid changes over the whole patterned fen area. Wet minerotrophic sedge fen vegetation was almost totally covered by ombrotrophic Sphagnum mosses within few decades. Even up to 50 cm high hummocks emerged on the patterned fen strings in an abrupt response that could be precisely dated by simultaneous encroachment of pine seedlings and from the aerial images. The recent apparent rate of carbon accumulation of the new Sphagnum peat was ca. 100 g m-2 -a. The other study site in the Ilajansuo aapa mire persists in a more pristine setting without significant disturbance in its catchment area. Here the mineral-water limit was studied across a transition between a bog zone and an aapa mire zone of the mire complex. We were able to exactly locate a 100 x 300-m special study area and repeat e.g. mapping of all trees, of all topographic patterns (hummocks, hollows

  3. Investigation of detergent effects on the solution structure of spinach Light Harvesting Complex II

    International Nuclear Information System (INIS)

    The properties of spinach light harvesting complex II (LHC II), stabilized in the detergents Triton X-100 (TX100) and n-Octyl-β-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.

  4. Land-use history affects understorey plant species distributions in a large temperate-forest complex, Denmark

    DEFF Research Database (Denmark)

    Svenning, J.-C.; Baktoft, Karen H.; Balslev, Henrik

    2009-01-01

    spatial, and 5 historical variables, and principal components analysis (PCA), redundancy analysis (RDA) as well as indicator species analysis. The historical variables were status as ancient (1805 AD) high forest, reclaimed bogs, ≤100 m from Bronze Age burial mounds, or former conifer plantation......, and stand age. The PCA results showed that the main gradients in species composition were strongly related to the explanatory variables. Forward variable selection and variation partitioning using RDA showed that although modern environment was the dominant driver of species composition, anthropogenic...... historical factors were also important. The pure historical variation fraction constituted 13% of the variation explained. The RDA results showed that ancient-forest status and, secondarily, reclaimed bog status were the only significant historical variables. Many typical forest interior species, with poor...

  5. Study of natural U-Th series radionuclides behaviour in superficial water for management of water quality in U mine environment

    International Nuclear Information System (INIS)

    Full text: Superficial water contamination by natural U-Th series radionuclides may have an impact on the quality of water and consequently on human health. Therefore, we investigate radionuclides content of a brook (Sagnes, Limousin, France) which floods a peat bog contaminated by a former uranium mine. Chemical behaviour of several decay products of the U-series radionuclides in natural waters is still poorly known, especially in the 235U family. In order to prevent a potential contamination, the speciation of U-series nuclides must be studied. The strategy consists in analyzing waters up and downstream the peat bog to investigate the physical form of radionuclides: particulate, colloidal or dissolved. After filtration (0.45 μm) and ultrafiltration (10 kD), water samples are measured for their gamma activity with very low background, high efficiency gamma spectrometers implanted in the Underground Laboratory of Modane (France). After two counting stages, activities of 235-238U, 234-228-227Th, 226-228-223Ra, 210Pb and 7Be are determined. Downstream the peat bog, whereas 238U increases by a factor of 15 to 40, 226Ra increases by a factor of 6 to 14 and 232Th family does not vary. All radium isotopes are present in dissolved form. 234Th, decay product of 238U, is mostly associated with the colloidal fraction while 232Th is always particular. 210Pb in the brook upstream the mine influence is dissolved whereas the same isotope discharged by the peat bog is in the particulate form. Moreover we found an important (20 mBq/L) activity of 227Ac in the 227Ac has a high conversion factor (1.1 μSv/Bq) and it should be taken into account in the equivalent dose estimates. (author)

  6. Les flèches de galets de Bretagne : morphodynamiques passée, présente et prévisible

    OpenAIRE

    Stéphan, Pierre

    2008-01-01

    The gravel spits morphodynamic is studied at different timescales. At long timescale (103 years), the holocene evolution of sptis is studied by stratigraphical analyses of salt marshes sedimentary deposits. In the same time, sea-level curve is reconstructed using a transfert function based on foraminifera. A phase of stability of the sea-level between 5500 BP and 4800 BP permit the development of the peat bogs near the actual shoreline. Between 4800 BP and 3000 BP, sea-level transgression cau...

  7. Long cores from small lakes—recovering up to 100 m-long lake sediment sequences with a high-precision rod-operated piston corer (Usinger-corer)

    OpenAIRE

    Jens Mingram; Jörg F W Negendank; Achim Brauer; Dieter Berger; Andreas Hendrich; Marina Köhler; Usinger, H.

    2007-01-01

    We present a unique, versatile piston corer for recovering continuous lake and bog sediment sequences with superior accuracy and quality. The main components of the system and their function are described, with special focus on measures for obtaining long, continuous lake sediment sections up to a current maximum length of 95 m. Examples of lake sediment profiles obtained with this system from different climatic zones are presented.

  8. 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.

  9. 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...... of aerenchymous plants should be considered before dismissing grasslands on peat as CH4 sources....

  10. Møder der kommer os i møde

    DEFF Research Database (Denmark)

    Ravn, Ib

    (Bagsidetekst) Hvis man skal arrangere et større møde med oplæg, ender det tit med at blive et tæppebombardement af PowerPoint-præsentationer. Denne bog giver ideer til, hvordan man kan involvere deltagerne og lade dem bearbejde og anvende dagens input – under mødet, i samtale med de andre...

  11. Transformation Studio 2016: Future Geopark Odsherred

    OpenAIRE

    2016-01-01

    What if the vacant radio station at Skamlebæk became the new visitor center and gateway to the Geopark Odsherred? How can landscape design communicate the finding place of the sun chariot in the Trundholm bog? And can we rework the water system of the reclaimed Lammefjord for sustainable farming, nature development and tourism? This volume presents strategic design work by landscape architecture students at the University of Copenhagen. From February to April 2016, 23 students from 11 countri...

  12. Retfærdiggørelse, ideologi, kritik

    DEFF Research Database (Denmark)

    Albertsen, Niels

    Denne artikel har tre formål. For det første er det hensigten at udrede forbindelserne mellem begreberne retfærdiggørelse, ideologi og kritik, som de foreligger hos Luc Boltanski og Ève Chiapello i Le nouvel esprit du capitalisme  (1999) (NEC i det følgende) og denne bogs forudsætninger. For det ...

  13. Retfærdiggørelse, ideologi, kritik

    DEFF Research Database (Denmark)

    Albertsen, Niels

    2008-01-01

    Denne artikel har tre formål. For det første er det hensigten at udrede forbindelserne mellem begreberne retfærdiggørelse, ideologi og kritik, som de foreligger hos Luc Boltanski og Ève Chiapello i Le nouvel esprit du capitalisme  (1999) (NEC i det følgende) og denne bogs forudsætninger. For det ...

  14. At redde utopien af historiens katastrofe

    DEFF Research Database (Denmark)

    Rösing, Lilian Munk

    2011-01-01

    I to aktulle danske litterære værker, Mette Moestrups Jævnet med jorden og Ursula og Julie Andkjær Olsens Have og helvede, synes utopien at have fået en chance til. Moestrups bog kan læses som en bevægelse fra utopi i betydningen "det gode sted" til atopi i betydningen "det der ikke har noget ste...

  15. Forest responses to late Holocene climate change in north-central Wisconsin: a high- resolution study from Hell's Kitchen Lake.

    Science.gov (United States)

    Urban, M. A.; Booth, R. K.; Jackson, S. T.; Minckley, T. A.

    2007-12-01

    Forest dynamics at centennial to millennial timescales can be identified using paleoecological records with high spatial, temporal, and taxonomic resolution. These dynamics are linked to climate changes by comparing the paleoecological records with independent paleoclimate records of complementary sensitivity and temporal resolution. We analyzed plant macrofossils at contiguous 1cm intervals (representing 5 to 35 yr/cm) from late Holocene sediments of Hell's Kitchen Lake (3 ha) in north-central Wisconsin. Most of the plant macrofossils derive from trees growing on the slopes directly adjacent to the lake, and were identified to the species. We also analyzed pollen at an approximately100 year resolution to provide a regionally integrated record of forest composition. We then compared the macrofossil and pollen records with independent records of climate change in the region, particularly paleohydrological records from kettle bogs. The most notable feature of the late Holocene record occurs between 2300-2000 cal yr BP. During this period yellow birch (Betula alleghaniensis) macrofossils first appear in the record, along with a corresponding increase in pollen percentages. Hemlock (Tsuga canadensis) macrofossils and pollen also show a marked increase at this time. These changes coincide with a major transition towards wetter conditions recorded in the testate amoebae record of Hornet Bog (~200km northwest) and in a number of other kettle bog records from the region. Directly following this transition, tamarack (Larix laricina) and Sphagnum macrofossils at Hell's Kitchen Lake increase dramatically, likely representing the initiation of bog-mat growth along the southwest margin of the lake during the wet period. . We are continuing our high-resolution sampling downcore at Hell's Kitchen Lake. This will permit us to examine additional ecologic and climatic events in the early and mid-Holocene.

  16. 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. PMID:27280287

  17. Detection, Isolation, and Characterization of Acidophilic Methanotrophs from Sphagnum Mosses

    OpenAIRE

    N. Kip; Ouyang, W.J.; van der Winden, J.; Raghoebarsing, A.; van Niftrik, L.; De Pol, A.; Pan, Y.; L. Bodrossy; van Donselaar, E. G.; G. J. Reichart; M. S. M. Jetten; J. S. Sinninghe Damsté; Op den Camp, H.J.M.

    2011-01-01

    Sphagnum peatlands are important ecosystems in the methane cycle. Methane-oxidizing bacteria in these ecosystems serve as a methane filter and limit methane emissions. Yet little is known about the diversity and identity of the methanotrophs present in and on Sphagnum mosses of peatlands, and only a few isolates are known. The methanotrophic community in Sphagnum mosses, originating from a Dutch peat bog, was investigated using a pmoA microarray. A high biodiversity of both gamma- and alphapr...

  18. Bacteriohopanepolyol signatures as markers for methanotrophic bacteria in peat moss

    OpenAIRE

    van Winden, J.F.; H. M. Talbot; N. Kip; G. J. Reichart; De Pol, A.; N. P. McNamara; M. S. M. Jetten; Op den Camp, H.J.M.; J. S. Sinninghe Damsté

    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 extreme acidophilic verrucomicrobial methanotroph. A type I Methylovulum-like strain (M200) contains a remarkable combination of BHPs, including a complete suite of mono-unsaturated aminobacteriohopanepe...

  19. Various Litter Species and High Water-Table Levels Hamper Type II Methanotrophs in a Bare Peatland Regeneration Experiment

    OpenAIRE

    Siegenthaler, Andy; Gattinger, Andreas; Francez, Andre-Jean; Gilbert, Daniel; Buttler, Alexandre; Tonolla, Mauro; Mitchell, Edward A.D.

    2009-01-01

    Significant areas of temperate bogs have been damaged by peat harvesting. After abandonment and spontaneous regeneration, these secondary mires can become important methane sources towards the atmosphere (Basiliko et al., 2007). Recent studies have shown the importance of methane oxidising bacteria (MOB) for the recycling of carbon from methane effluxes (e.g., Dedysh et al., 2001; Raghoebarsing et al., 2005). We set up a factorial experiment that allowed us to tests the effects of three level...

  20. Detection, Isolation, and Characterization of Acidophilic Methanotrophs from Sphagnum Mosses ▿ †

    OpenAIRE

    Kip, Nardy; Ouyang, Wenjing; van Winden, Julia; Raghoebarsing, Ashna; van Niftrik, Laura; Pol, Arjan; Pan, Yao; Bodrossy, Levente; Van Donselaar, Elly G.; Reichart, Gert-Jan; Jetten, Mike S. M.; Sinninghe Damsté, Jaap S.; Op Den Camp, Huub J M

    2011-01-01

    Sphagnum peatlands are important ecosystems in the methane cycle. Methane-oxidizing bacteria in these ecosystems serve as a methane filter and limit methane emissions. Yet little is known about the diversity and identity of the methanotrophs present in and on Sphagnum mosses of peatlands, and only a few isolates are known. The methanotrophic community in Sphagnum mosses, originating from a Dutch peat bog, was investigated using a pmoA microarray. A high biodiversity of both gamma- and alphapr...

  1. PUMA Pædagogisk udredningsmateriale til AKT - og specialundervisning

    DEFF Research Database (Denmark)

    Kristensen, René

    2011-01-01

    PUMA er et nyudviklet pædagogisk udredningsmateriale bestående af en bog samt en cd med 35 opgaver, modeller og skemaer til udskrivning på skolelicensvilkår. Materialet arbejder ud fra anerkendte teorier som systemisk konstruktionisme, selvpsykologi, samt kognitive teorier om hukommelse, analyse og...... lignende. Der kan downloades en flyer, samt supplerende materiale fra www.rkris.dk/PUMA...

  2. Fotochemicky generované oxidační částice v přírodních vodách, ověření funkce erioglaucinu jako činidla na stanovení hydroxylových radikálů.

    OpenAIRE

    PAVLÍKOVÁ, Zuzana

    2008-01-01

    The bachelor thesis is focused on a dye erioglaucine and its function as a scavenger of hydroxyl radicals. The experimental part of the thesis deal with photochemical stability of erioglaucine; degradation of erioglaucine in a model system with photochemical hydroxyl radicals production from nitrate ions; degradation of erioglaucine in reaction mixtures with natural humic samples from upper soil horizont or from peat bog. A kinetic model for the reaction erioglaucine + hydroxyl radicals has b...

  3. Reconstruction of Holocene carbon dynamics in a large boreal peatland complex, southern Finland

    Science.gov (United States)

    Mathijssen, Paul J. H.; Väliranta, Minna; Korrensalo, Aino; Alekseychik, Pavel; Vesala, Timo; Rinne, Janne; Tuittila, Eeva-Stiina

    2016-06-01

    Holocene peatland development and associated carbon (C) dynamics were reconstructed for a southern boreal Finnish peatland complex with fen and bog areas. In order to assess the role of local factors and long-term allogenic climate forcing in peatland development patterns, we studied a total of 18 peat cores and reconstructed vertical peat growth and lateral peat area expansion rates, the C accumulation rate (CAR), past vegetation composition and past methane (CH4) fluxes. We combined fossil plant data with measured contemporary CH4 flux - vegetation relationship data to reconstruct CH4 fluxes over time. When these reconstructions were added to the CAR estimations, a more complete picture of Holocene-scale C dynamics was achieved. Basal peat ages showed that expansion of the peat area was rapid between 11,000 and 8000 cal. BP, but decreased during the dry mid-Holocene and is probably currently limited by basal topography. A similar pattern was observed for peat growth and CAR in the fen core, whereas in the bog core CAR increased after ombrotrophication, i.e. after 4400 cal. BP. The effect of fire on vegetation and CAR was more conspicuous at the bog site than at the fen site. The CH4 flux reconstructions showed that during the Holocene CH4 emissions at the fen site decreased from 19 ± 15 to 16 ± 8 g CH4 m-2 yr-1 and at the bog site from 20 ± 15 to 14 ± 8 g CH4 m-2 yr-1. Our results suggest that a combination of changing climate, fire events and local conditions have modified the autogenic peatland development and C dynamics.

  4. Vold

    DEFF Research Database (Denmark)

    Žižek, Slavoj

    Vold er ikke blot kriminalitet og terrorisme, som forstyrrer den normale og rolige orden. Der er nemlig en større vold bygget ind i selve denne orden. Med udgangspunkt i denne påstand og ved hjælp af Kant, Lacan, vittigheder og Hollywood-film diskuterer Slavoj Žižek i denne bog både aktuelle poli...

  5. Anmeldelse af Ulrik Rammeskow Bang-Pedersen & Lasse Højlund Christensen: Den civile retspleje, 2. udg., 2010

    DEFF Research Database (Denmark)

    Werlauff, Erik

    2011-01-01

    Artiklen anmelder den nævnte bog og giover den videnskabelig og pøædagogiski anerkendelse for på en læseværdig måde at redegøre for, hvordan domstolene i Danmark er opbygget, og hvordan en civil retssag behandles. En lang række af kapitlerne hos Ulrik Rammeskow Bang-Pedersen & Lasse Højlund...

  6. Lærerprofiler i dansk. Nye mål og kompetencer 1

    DEFF Research Database (Denmark)

    Carlsen, Benny Bang; Mølgaard, Niels

    Denne første bog i serien, basisbogen, introducerer den studerende til danskfaget i den nye læreruddannelse, LU13. Basisbogen giver indsigt i det paradigmeskifte, der har fundet sted i form af kompetencemålsstyring med fokus på vidensmål, færdighedsmål og kompetencemål. Bogen præsenterer en...

  7. Musik som medicin

    DEFF Research Database (Denmark)

    Ridder, Hanne Mette Ochsner

    2005-01-01

    Den første bog, der beskriver bredden inden for området MusikMedicin, starter helt ved begyndelsen, ved ”cellernes sang”, og går derefter videre til at berette om et utal af undersøgelser og teorier om, hvordan musik påvirker både foster og mor, planter og dyr, krop og følelser, immunsystem og...

  8. Charring temperatures are driven by the fuel types burned in a peatland wildfire

    Directory of Open Access Journals (Sweden)

    Victoria A. Hudspith

    2014-12-01

    Full Text Available Peatlands represent a globally important carbon store; however, the human exploitation of this ecosystem is increasing both the frequency and severity of fires on drained peatlands. Yet, the interactions between the hydrological conditions (ecotopes, the fuel types being burned, the burn severity, and the charring temperatures (pyrolysis intensity remain poorly understood. Here we present a post-burn assessment of a fire on a lowland raised bog in Co. Offaly, Ireland (All Saints Bog. Three burn severities were identified in the field (light, moderate, and deeply burned, and surface charcoals were taken from 17 sites across all burn severities. Charcoals were classified into two fuel type categories (either ground or aboveground fuel and the reflectance of each charcoal particle was measured under oil using reflectance microscopy. Charcoal reflectance shows a positive relationship with charring temperature and as such can be used as a temperature proxy to reconstruct minimum charring temperatures after a fire event. Resulting median reflectance values for ground fuels are 1.09 ± 0.32%Romedian, corresponding to estimated minimum charring temperatures of 447°C ± 49°C. In contrast, the median charring temperatures of aboveground fuels were found to be considerably higher, 646°C ± 73°C (3.58 ± 0.77%Romedian. A mixed-effects modelling approach was used to demonstrate that the interaction effects of burn severity, as well as ecotope classes, on the charcoal reflectance is small compared to the main effect of fuel type. Our findings reveal that the different fuel types on raised bogs are capable of charring at different temperatures within the same fire, and that the pyrolysis intensity of the fire on All Saints Bog was primarily driven by the fuel types burning, with only a weak association to the burn severity or ecotope classes.

  9. Hyperstress

    DEFF Research Database (Denmark)

    Baldursson, Einar Baldvin

    Stress er et stort problem i vores moderne hverdag med det moderne arbejdsliv, der konstant kræver omstillingsparathed. Alligevel forsøger vi at finde 'gamle' og traditionelle løsninger på, hvordan vi skal bekæmpe stress. Denne bog forslår i stedet, at vi finder en ny, fremadrettet forståelse af...

  10. Ledelse af Netværk

    DEFF Research Database (Denmark)

    Waldstrøm, Christian; Engelbrecht, Bent

    Vi er alle stærkt præget af de relationer, vi har, både professionelt og privat. Uanset om vi er klar over det eller ej, påvirker de vores muligheder og er algørende for, hvordan organisationer fungerer. Med denne bog sætter Christian Waldstrøm og Bent Engelbrecht fokus på virksomhedens netværk o...

  11. "Jesli ne võskazhu eto..." : [luuletused] / Doris Kareva ; per. Marina Tervonen, järelsõna: Jan Kaus

    Index Scriptorium Estoniae

    Kareva, Doris, 1958-

    2005-01-01

    Sisu: "Jesli ne võskazhu eto..." ; "Zhizn i son - listja..."; "V dome, tshto ja minoval, zazvonil telefon..." ; "Tshto-to vzorvalos: bomba..." ; "Budushtsheje proishodit seitshas..." ; "Kazhdaja do kontsa dodumannaja mõsl..." ; "Ni vremeni, ni deneg, no prostranstvo..." ; "Tõ raskrõvajesh menja, kak knigu..." ; "U zhizni net istorii..." ; "Po proshestvii let otkuporju vino tvoihh slov..." ; "Tshtobõ võdohnut..." ; "Bog bogemen..."

  12. Environmental and anthropogenic controls over bacterial communities in wetland soils

    OpenAIRE

    Hartman, Wyatt H.; Curtis J Richardson; Vilgalys, Rytas; Bruland, Gregory L.

    2008-01-01

    Soil bacteria regulate wetland biogeochemical processes, yet little is known about controls over their distribution and abundance. Bacteria in North Carolina swamps and bogs differ greatly from Florida Everglades fens, where communities studied were unexpectedly similar along a nutrient enrichment gradient. Bacterial composition and diversity corresponded strongly with soil pH, land use, and restoration status, but less to nutrient concentrations, and not with wetland type or soil carbon. Sur...

  13. Late Holocene climatic changes in Tierra del Fuego based on multiproxy analyses of peat deposits

    OpenAIRE

    Mauquoy, D.; Blaauw, Maarten; van Geel, B; Borromei, A.; M. Quattrocchio; Chambers, F.M.; Possnert, G.

    2004-01-01

    A ca. 1400-yr record from a raised bog in Isla Grande, Tierra del Fuego, Argentina, registers climate fluctuations, including a Medieval Warm Period, although evidence for the 'Little Ice Age' is less clear. Changes in temperature and/or precipitation were inferred from plant macrofossils, pollen, fungal spores, testate amebae, and peat humification. The chronology was established using a C-14 wiggle-matching technique that provides improved age control for at least part of the record compare...

  14. Breaking Empirical Deadlocks in the Study of Partisanship: An Overview of Experimental Research Strategies

    Directory of Open Access Journals (Sweden)

    Donald P. Green

    2013-03-01

    Full Text Available The vast literature on party identification has gradually become bogged down by disputes about how to interpret observational data. This paper proposes the use of experimental designs to shed light on the responsiveness of party identification to short term forces such as retrospective performance evaluations. Examples of recent field experiments are used to illustrate two types of experimental designs and the assumptions on which they rest.

  15. "Net, ne nuzhnõ mne Pitera dozhdi..." : [luuletused] / Lilija Novogrudskaja (Samson)

    Index Scriptorium Estoniae

    Novogrudskaja, Lilija

    2003-01-01

    Sisu: "Net, ne nuzhnõ mne Pitera dozhdi..." ; "V Narva-Jõesuu segodnja dozhdi..." ; Nojabrskije zarissovki ; "Nash bog jedin! Mõ zh rvjom jego na tshasti..." ; "Vozmozhno l, drug moi, prosvetljonnõi..." ; "Ja prosnulas..." ; "Ja smotrela v okno..." ; "Ja tak toskuju po tvoim gubam..." ; "Ja otreklas ot tebja pozdno..." ; "Vtshera ja tantsevala s morem..." ; "Vse vzorvalos vnutri ot ispuga..." ; Nemnogo ironii ; "Segodnja ne stalo babushki..." ; "Tronula ja hod tshasov..." ; "Na vershine l mira ja, il na dne kolodtsa..."

  16. Influence of lake water pH and alkalinity on the distribution of coreand intact polar branched glycerol dialkyl glycerol tetraethers (GDGTs) in lakes

    OpenAIRE

    Schoon, P. L.; de Kluijver, A.; Middelburg, J.J.; J. A. Downing; Sinninghe Damsté, J. S.; Schouten, S.

    2013-01-01

    Branched glycerol dialkyl glycerol tetraethers (GDGTs) are bacterial membrane lipids, ubiquitously present in soils and peat bogs, as well as in rivers, lakes and lake sediments. Their distribution in soil is controlled mainly by pH and mean annual air temperature, but the controls on their distribution in lake sediments are less well understood. Several studies have found a relationship between the distribution of branched GDGTs in lake sediments and average lake water pH, suggesting an aqua...

  17. Narhvalen og Nordkaperen

    DEFF Research Database (Denmark)

    Nørby, Søren

    orlogsskibe bygget på Orlogsværftet, gør kun deres historie mere interessant. Denne bog beskriver de to bådes historie fra tilblivelsen under Den Kolde Krig til deres udfasning næsten 40 år senere. Undervejs fortælles om maskineri, sensorer, våben, livet om bord, samt ikke mindst hvordan ubådene ville være...

  18. Social Quality

    DEFF Research Database (Denmark)

    Jensen, Niels Rosendal

    2012-01-01

    Anmeldelsen af Peter Herrmanns bog om global socialpolitik omtaler både forståelsen af, hvad social kvalitet er, og hvordan dette begreb er udviklet. PÅ denne baggrund er det muligt at forholde sig kritisk til fx. EUs måde at samtænke økonomi, beskæftigelse og socialpolitik på. Alternativt kan de...

  19. DOE Zero Energy Ready Home Case Study: Weiss Building & Development, Downers Grove, Illinois

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2013-09-01

    This single-family home built in a peat bog has underground storage tanks and drainage tanks, blown fiberglass insulation, coated rigid polyisocyanurate, and flashing. The 3,600-square-foot custom home built by Weiss Building & Development LLC is the first home in Illinois certified to the DOE Challenge Home criteria, which requires that homes meet the EPA Indoor airPlus guidelines.The builder won a 2013 Housing Innovation Award in the custom builder category.

  20. Environmental change in NW Iberia between 7000 and 500 cal BC

    OpenAIRE

    Martínez Cortizas, Antonio; Costa-Casais, Manuela; López Sáez, José Antonio

    2009-01-01

    [EN] We review research done on environmental changes in northwest (NW) Iberia spanning from the beginning to the late Holocene (7000–500 cal. BC). The type of archives (peat bogs, lake sediments, colluvium, soils, etc.) and proxies (pollen, element concentrations, isotopes, etc.) that were used to reconstruct changes on climate, soils, vegetation and atmospheric metal pollution are briefly described. Then we synthesize what the records suggest about the ecological history of NW Iberia. We id...