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Sample records for uraniferous bog deposit

  1. Geology and recognition criteria for uraniferous humate deposits, Grants Uranium Region, New Mexico. Final report

    SciTech Connect

    Adams, S.S.; Saucier, A.E.

    1981-01-01

    The geology of the uraniferous humate uranium deposits of the Grants Uranium Region, northwestern New Mexico, is summarized. The most important conclusions of this study are enumerated. Although the geologic characteristics of the uraniferous humate deposits of the Grants Uranium Region are obviously not common in the world, neither are they bizarre or coincidental. The source of the uranium in the deposits of the Grants Uranium Region is not known with certainty. The depositional environment of the host sediments was apparently the mid and distal portions of a wet alluvial fan system. The influence of structural control on the location and accumulation of the host sediments is now supported by considerable data. The host sediments possess numerous important characteristics which influenced the formation of uraniferous humate deposits. Ilmenite-magnetite distribution within potential host sandstones is believed to be the simplest and most useful regional alteration pattern related to this type of uranium deposit. A method is presented for organizing geologic observations into what is referred to as recognition criteria. The potential of the United States for new districts similar to the Grants Uranium Region is judged to be low based upon presently available geologic information. Continuing studies on uraniferous humate deposits are desirable in three particular areas.

  2. The Robinson and Weatherly uraniferous pyrobitumen deposits near Placerville, San Miguel County, Colorado

    USGS Publications Warehouse

    Wilmarth, V.R.; Vickers, R.C.

    1953-01-01

    Uranium deposits that contain uraniferous pyrobitumen of possible hydrothermal origin occur at the Weatherly and Robinson properties near Placerville, San Miguel County, Colo. These deposits were mined for copper, silver, and gold more than 50 years ago and were developed for uranium in 1950. The Robinson property, half a mile east of Placerville, consists of the White Spar, New Discovery Lode, and Barbara Jo claims. The rocks in this area are nearly horizontal sandstones, shales, limestones, and conglomerates of the Cutler formation of Permian age and the Dolores formation of Triassic and Jurassic (?) age. These rocks have been faulted extensively and intruded by a Tertiary (?) andesite porphyry dike. Uranium-bearing pyrobitumen associated with tennantite, tetrahedrite, galena, sphalerite, chalcopyrite, bornite, azurite, malachite, calcite, barite, and quartz occurs in a lenticular body as much as 40 feet long and 6 feet wide along a northwest-trending, steeply dipping normal fault. The uranium content of eleven samples from the uranium deposit ranges from 0.001 to 0.045 percent uranium and averages about 0.02 percent uranium. The Weatherly property, about a mile northwest of Placerville, consists of the Black King claims nos. 1, 4, and 5. The rocks in this area include the complexly faulted Cutler formation of Permian age and the Dolores formation of Triassic and Jurassic (?) age. Uranium-bearing pyrobitumen arid uranophane occur, along a northwest-trending, steeply dipping normal fault and in the sedimentary rocks on the hanging wall of the fault. Lens-shaped deposits in the fault zone are as much as 6 feet long and 2 feet wide and contain as much as 9 percent uranium; whereas channel samples across the fault zone contain from 0.001 to 0.014 percent uranium. Tetrahedrite, chalcopyrite, galena, sphalerite, fuchsite, malachite, azurite, erythrite, bornite, and molybdite in a gangue of pyrite, calcite, barite, and quartz are associated with the uraniferous material

  3. Possibilities for detailed dating of peat bog deposits

    SciTech Connect

    Punning, J.; Ilomets, M.; Koff, T. )

    1993-01-01

    Geochemical and palynological data as well as radiocarbon dating were used to study the peat bog deposits in Niinsarre bog, northeast Estonia. The aim of this study was to establish criteria for determining a detailed chronology, which is important, for example, in studying paleoevents and historical monitoring. In some cases, they can use cumulative pollen data, as well as cumulative chemical and peat bulk density data. Material was gathered for [sup 14]C dating from three parallel samples taken from cores ca. 10--20 cm apart using a Russian peat sampler. Samples for peat bulk density, palynological and chemical measurements were taken from the same cores. To measure peat bulk density, the authors used a continuous sampling method. Sampling frequency was calculated to cover layers formed over 50 yr.

  4. The biogeochemistry of an ombrotrophic bog: Evaluation of use as an archive of atmospheric mercury deposition

    SciTech Connect

    Benoit, J.M.; Fitzgerald, W.F.; Damman, A.W.H.

    1998-08-01

    The utility of ombrotrophic bogs as archives of atmospheric mercury deposition was assessed with an investigation in Arlberg Bog, Minnesota, US. Since the use of ombrotrophic bogs as archives depends on the immobility of deposited trace metals, the authors examined the postdepositional transport processes revealed by the solid-phase distributions of mercury and ancillary metals in this bog. They modeled metal speciation in bog pore-waters as a function of pe in order to understand metal behavior in ombrotrophic peat. Specifically, they considered the effect of water movement and resultant shifts in redox potential gradients on metal retention. The results indicate that Hg and Pb are immobile in ombrotrophic peat, so their distribution can be used to determine temporal changes in deposition. To substantiate the deposition estimates determined in this study, they emphasized the importance of confirming the validity of the dating scheme, assessing the degree of horizontal homogeneity in the accumulation record, and providing evidence for retention of Hg based on geochemical modeling. As recorded in Arlberg Bog, historic atmospheric Hg deposition increased gradually after the mid-1800s, peaked between 1950 and 1960, and may have declined thereafter. Preindustrial deposition was about 4 {micro}g/m{sup 2} year and recent deposition about 19 {micro}g/m{sup 2} year. The results of this study indicate that deposition at Arlberg Bog has been influenced by a regional and/or local-scale source.

  5. Bog bodies.

    PubMed

    Lynnerup, Niels

    2015-06-01

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

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

    NASA Astrophysics Data System (ADS)

    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

  7. Atmospheric Mercury Transfer to Peat Bogs Dominated by Gaseous Elemental Mercury Dry Deposition.

    PubMed

    Enrico, Maxime; Roux, Gaël Le; Marusczak, Nicolas; Heimbürger, Lars-Eric; Claustres, Adrien; Fu, Xuewu; Sun, Ruoyu; Sonke, Jeroen E

    2016-03-01

    Gaseous elemental mercury (GEM) is the dominant form of mercury in the atmosphere. Its conversion into oxidized gaseous and particulate forms is thought to drive atmospheric mercury wet deposition to terrestrial and aquatic ecosystems, where it can be subsequently transformed into toxic methylmercury. The contribution of mercury dry deposition is however largely unconstrained. Here we examine mercury mass balance and mercury stable isotope composition in a peat bog ecosystem. We find that isotope signatures of living sphagnum moss (Δ(199)Hg = -0.11 ± 0.09‰, Δ(200)Hg = 0.03 ± 0.02‰, 1σ) and recently accumulated peat (Δ(199)Hg = -0.22 ± 0.06‰, Δ(200)Hg = 0.00 ± 0.04‰, 1σ) are characteristic of GEM (Δ(199)Hg = -0.17 ± 0.07‰, Δ(200)Hg = -0.05 ± 0.02‰, 1σ), and differs from wet deposition (Δ(199)Hg = 0.73 ± 0.15‰, Δ(200)Hg = 0.21 ± 0.04‰, 1σ). Sphagnum covered during three years by transparent and opaque surfaces, which eliminate wet deposition, continue to accumulate Hg. Sphagnum Hg isotope signatures indicate accumulation to take place by GEM dry deposition, and indicate little photochemical re-emission. We estimate that atmospheric mercury deposition to the peat bog surface is dominated by GEM dry deposition (79%) rather than wet deposition (21%). Consequently, peat deposits are potential records of past atmospheric GEM concentrations and isotopic composition.

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

    NASA Astrophysics Data System (ADS)

    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

  9. Biological N2-Fixation Increases with Peatland Age and Decreases with N Deposition in Bogs of Western Canada

    NASA Astrophysics Data System (ADS)

    Fillingim, H.; Popma, J. M.; Dynarski, K. A.; Wieder, R.; Vile, M. A.

    2013-12-01

    Most terrestrial ecosystems are thought be limited primarily by nitrogen, including boreal peatlands located in pristine regions. Bogs receive nutrients solely from atmospheric deposition. Because of the historically low rates of atmospheric nitrogen deposition in Alberta, Canada, the Sphagnum mosses that dominate bog ground cover in this region have formed relationships with diazotrophs in order to meet their nitrogen needs, making biological N2- fixation the dominant input of new nitrogen to these bogs. The process of N2-fixation is highly variable and is governed by a number of environmental factors. In Alberta, one factor is water availability, as these bogs occur in some of the driest climates in which peatlands are known to exist. More recent factors with the potential to greatly alter N2-fixation dynamics include increasing nitrogen deposition associated with the growing oil sands mining operations and wildfires increasing in frequency and severity with global climate change. To determine the potential importance of N2-fixation to the overall peatland nitrogen balance under current and future conditions, we incubated the moss Sphagnum fuscum, using the acetylene reduction assay calibrated with 15N2, from 3 bogs representing ages of 3, 13, and 30 years since fire. Each bog was fertilized 8 times throughout the growing season with 0, 10, and 20 kg N/ha/yr. N2-fixation rates were measured 5 times at each site throughout the summer of 2013 to account for variation due to season and weather. Mean rates of N2-fixation increased with bog age, with higher rates in the 30 year old bog (36.90 × 8.38) and subsequently lower rates in the 13 yr (25.08 × 5.63) and 3 yr (11.58 × 6.33) old bogs. As expected, we saw decreasing rates of N2-fixation in the 10 (16.96 × 5.39) and 20 kg N/ha/yr treatments (3.35 × 1.34), as compared to water-only controls (47.62 × 12.18). These results indicate that N2-fixation supplies abundant N to support net primary productivity for bogs

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

    NASA Astrophysics Data System (ADS)

    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

  11. Mercury deposition in ombrotrophic bogs in New Brunswick, Nova Scotia and Prince Edward Island. Atlantic region surveillance report number EPS-5-AR-98-4

    SciTech Connect

    Rutherford, L.A.; Matthews, S.L.

    1998-12-31

    A study was conducted to determine historical atmospheric mercury deposition patterns in the Maritime Provinces. Investigators measured mercury concentrations in peat cores from five ombrotrophic bogs in Kejimkujik, Fundy, Kouchibougouac, and Cape Breton Highlands national parks and in East Baltic Bog, Prince Edward Island. Results presented and discussed include deposition rates calculated using lead-210 date estimates, temporal trends in mercury concentrations, and spatial patterns of mercury deposition.

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

    NASA Astrophysics Data System (ADS)

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

    2008-06-01

    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 mesocosms from the center and edge before, during, and following a drainage experiment as well as carbon dioxide release from disturbed unfertilized and nitrogen fertilized surface peat. In the field, methane fluxes ranged from 0 to 3.8 mg m-2 h-1 and were highest from hollows. Field nitrous oxide fluxes ranged from 0 to 574 μg m-2 h-1 and were elevated at the edge. A large Eriophorum vaginatum tussock showed decreasing nitrous oxide release as the season progressed. Drainage of mesocosms decreased methane release to 0, even during rewetting. There was a tendency for a decrease of nitrous oxide release during drainage and for an increase in nitrous oxide release during rewetting. Nitrogen fertilization did not increase decomposition of surface peat. Our examinations suggest a competition between vascular vegetation and denitrifiers for excess nitrogen. We also provide evidence that the von Post humification index can be used to explain nitrous oxide release from bogs, if the role of vascular vegetation is also considered. An assessment of the greenhouse gas release from nitrogen saturated restoring bogs needs to take into account elevated release from fresh Sphagnum peat as well as from sedges growing on decomposed peat. Given the high atmospheric nitrogen deposition, restoration will not be able to achieve an oligotrophic ecosystem in the short term.

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

    PubMed

    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.

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

    PubMed

    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.

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

    PubMed

    Allan, Mohammed; Le Roux, Gael; Sonke, Jeroen E; 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 1,500 years. Mercury concentrations in the four cores ranged from 16 to 1,100 μg kg(-1), with the maxima between 840 and 1,100 μg kg(-1). A chronological framework was established using radiometric (210)Pb and (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 1,300 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.

  16. Source characterisation of atmospheric platinum group element deposition into an ombrotrophic peat bog.

    PubMed

    Rauch, Sebastien; Hemond, Harold F; Peucker-Ehrenbrink, Bernhard

    2004-04-01

    Platinum, palladium, rhodium, iridium and osmium were found to be enriched relative to their expected natural concentrations in peat samples from Thoreau's Bog, an ombrotrophic peat bog in Concord, Massachusetts. The source of osmium into the bog was determined from its isotopic composition (187Os/188Os). Osmium is composed of 4% lithogenic osmium from atmospheric soil dust, 41% of anthropogenic osmium and 55% of osmium from a non-lithogenic, non anthropogenic source, with rain being a likely candidate for the latter. Significant anthropogenic and rain contributions are also expected for iridium. In contrast, platinum, palladium and rhodium are almost exclusively anthropogenic. The larger enrichments of platinum, palladium and rhodium indicate that automobile catalysts are the source of platinum group elements to Thoreau's bog. The bog is located approximately 300 m from a major road and, therefore, the occurrence of platinum elements is evidence for regional dispersion of these metals. The absence of a clear trend following the introduction of catalysts indicates that platinum group elements are not quantitatively conserved in peat with downward leaching and plants playing an important role in the accumulation of platinum group elements.

  17. Retention of As and Sb in ombrotrophic peat bogs: records of As, Sb, and Pb deposition at four Scottish sites

    SciTech Connect

    Joanna M. Cloy; John G. Farmer; Margaret C. Graham; Angus B. MacKenzie

    2009-03-15

    Possible postdepositional As migration in ombrotrophic peat bogs was investigated by comparing depth profiles of As with those of Sb and Pb, two elements considered to be essentially immobile in peat, and those of redox-sensitive, potentially mobile nutrient elements such as Mn, Fe, P, and S in {sup 210}Pb-dated cores from four Scottish bogs. Concentration profiles of As were similar to those of Sb and Pb rather than these other elements, indicating that As is bound strongly to organic matter and is relatively immobile in ombrotrophic peat. Historical records of atmospheric anthropogenic As, Sb, and Pb deposition during the industrial and postindustrial periods were derived, site-specific maxima (up to 1.55, 1.33, and 45 mg m{sup -2} y{sup -1}, respectively) occurring between the late 1890s and 1960s, reflecting emissions from diverse sources such as mining and smelting, coal combustion, and also, in the case of Pb, exhaust emissions from the use of leaded gasoline. Since the mid-1980s, fluxes of Pb decreased (4-7 fold) more rapidly than those of As and Sb (2-3 fold), attributable to both the gradual elimination of leaded gasoline and recent new sources of the latter elements. Relative trends in derived anthropogenic As, Sb, and Pb deposition largely agreed with other Scottish peat and moss archive records, direct measurements of deposition, and UK emissions, i.e., four different types of data source. 36 refs., 3 figs., 1 tab.

  18. Geochemical Evidence for Periods of Increased Mineral Dust Deposition in Patagonian Peat Bogs Since the Last Deglaciation

    NASA Astrophysics Data System (ADS)

    Vanneste, H.; De Vleeschouwer, F.; Mattielli, N. D.; Vanderstraeten, A.; von Scheffer, C.; Piotrowska, N.; Coronato, A.; Le Roux, G.

    2013-12-01

    Atmospheric mineral dust plays an important role in the earth's climate system, influencing atmospheric parameters such as cloud condensation as well as biogeochemical cycles, affecting atmospheric CO2 levels. Antarctic ice core records show that mineral dust deposition has varied in the Southern Hemisphere over glacial-interglacial stages, suggesting major changes in atmospheric circulation. Nevertheless, to make predictions for the near future possible, a better understanding of atmospheric dust load and transport variability in the recent past, is essential. Ombrotrophic peat bogs have proven to provide excellent records of atmospheric dust deposition for the Holocene as their accumulation rates are higher than any other archive. Hence two ombrotrophic peat bogs, located southwest (Karukinka) and southeast (Harberton) on Isla Grande de Tierra del Fuego, were sampled to investigate dust-palaeoclimatic interactions in southern South America since the last deglaciation. Here we present a detailed geochemical (major, trace elements and Nd isotopes) record for both sites. The base of the peat sequences in Karukinka and Harberton were dated by 14C at ca. 8,000 cal yr BP and ca. 16,500 cal yr BP, respectively. The distribution of trace elemental (Sc, REE) concentrations within the cores indicates, besides tephra layers, episodes of increased mineral dust deposition at Harberton and Karukinka. The glacial-interglacial transition can be observed in the Harberton record (at ca. 11,500 cal yr BP), marked by a drop in the dust flux from 102 g/m2/yr to 10 g/m2/yr. The most significant episode of mineral dust deposition at Karukinka is concentrated around 1,600 cal yr BP with a maximum dust flux of 108 g/m2/yr. Its neodymium isotopic signature of -1 suggests crustal admixing, compared to the ɛNd values of ˜2, for both tephra layers.

  19. Reconnaissance of Colorado Front Range bogs for uranium and other elements

    SciTech Connect

    Owen, D.E.; Schumann, R.R.; Otton, J.K.

    1987-08-01

    Alpine bogs form along spring-fed valley floors and in steam drainages restricted by moraines, slides, and beaver dams. The bogs are generally young (Holocene) and contain a few tens of centimeters to several meters of peat and organic-rich muck. Organic matter has a great affinity for cations such as uranium; the geochemical enrichment factor between the peats and uraniferous ground water can approach 10,000 to 1. Because the bog sediments are geologically young, the uranium is in gross disequilibrium and has low radioactivity, thus it is undetectable by ground and aerial gamma surveys. Communities that derive a part of their water supplies from drainages containing uraniferous bogs face a potential health threat because the uranium is loosely bound and may easily be remobilized by ground water moving through the bogs. Reconnaissance sampling of bogs was conducted in the Colorado Front Range from the South Park area to the Colorado-Wyoming state line. Several bogs have uranium concentrations of 1000-3000 ppm, but most bogs have uranium concentrations in the 10-100 ppm range. Zinc concentrations of 100-1000 ppm are found in some bogs and many other metallic elements are present in concentrations between 10 and 100 ppm. Concentrations between 100 and 1000 ppm of some of the rare earth elements (e.g., Ce, La, Nd, Yb) were found in the Cripple Creek area.

  20. Scottish peat bog records of atmospheric vanadium deposition over the past 150 years: comparison with other records and emission trends.

    PubMed

    Cloy, Joanna M; Farmer, John G; Graham, Margaret C; MacKenzie, Angus B

    2011-01-01

    Cores from four Scottish ombrotrophic peat bogs were used to reconstruct the historical record of atmospheric vanadium (V) deposition in Scotland over the last 150 years. The general similarity of V and Pb concentration profile trends in (210)Pb-dated cores from each of the sites strongly suggested that V, like Pb, is essentially immobile in ombrotrophic peat. After allowance via use of the conservative element Ti for the contribution of soil dust V, the deposition of anthropogenic V was found to be greatest (∼ 1.3 to 2.0 mg m(-2) y(-1)) in the mid-20(th) century before decreasing to 0.1-0.3 mg m(-2) y(-1) in the early years of the 21(st) century. The latter values were in good agreement with directly measured atmospheric V fluxes at nearby sites, a finding also observed in the case of Pb. The decline in peat-core-derived fluxes for both V and Pb from 1970 to 2004, however, was not as large as the decline in official UK emission estimates for the two metals during this period. This, along with an order of magnitude discrepancy between the anthropogenic V/Pb ratios at the peat core surface and the higher values of the ratio for UK emissions in the early 2000s, suggests that the recently revised UK emissions data for V may perhaps still be overestimated and/or that some previously deposited Pb is being resuspended in the atmosphere.

  1. Historical records of atmospheric metal deposition along the St. Lawrence Valley (eastern Canada) based on peat bog cores

    NASA Astrophysics Data System (ADS)

    Pratte, Steve; Mucci, Alfonso; Garneau, Michelle

    2013-11-01

    The recent history of atmospheric As, Cd, Ni, Pb and Zn deposition and the stable Pb isotope signatures were reconstructed from short cores collected at three peat bogs along the St. Lawrence Valley (SLV). The onset of industrial activity was recorded around 1810-1850 AD. As, Cd, Pb and, to a certain extent, Ni deposition rates reached maxima between 1940 and the early 1970s. Trace metals likely originated from coal-burning and ore smelting between 1850 and 1950 AD, and were replaced thereafter, at least in the case of Pb, by the combustion of leaded gasolines until the mid-1980s. Trace metal contents and accumulation rates were greater in the two cores recovered from the southwestern SLV than further northeast, as expected from their proximity to urban and industrial centers of eastern Canada and the U.S. Mid-West and the direction of the prevalent winds. A rapid decrease in metal accumulation rates since the 1970s suggests that mitigation policies were effective in reducing atmospheric metal emissions. Nevertheless, metal accumulation rates and stable Pb isotope signatures have not yet returned to their pre-industrial values.

  2. Differential Effects of High Atmospheric N and S Deposition on Bog Plant/Lichen Tissue and Porewater Chemistry across the Athabasca Oil Sands Region.

    PubMed

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

    2016-12-06

    Oil extraction and development activities in the Athabasca Oil Sands Region of northern Alberta, Canada, release NOx, SOx, and NHy to the atmosphere, ultimately resulting in increasing N and S inputs to surrounding ecosystems through atmospheric deposition. Peatlands are a major feature of the northern Alberta landscape, with bogs covering 6-10% of the land area, and fens covering 21-53%. Bulk deposition of NH4(+)-N, NO3(-)-N, dissolved inorganic N (DIN), and SO4(2-)-S, was quantified using ion-exchange resin collectors deployed at 23 locations, over 1-6 years. The results reveal maximum N and S deposition of 9.3 and 12.0 kg ha(-1) yr(-1), respectively, near the oil sands industrial center (the midpoint between the Syncrude and Suncor upgrader stacks), decreasing with distance to a background deposition of 0.9 and 1.1 kg ha(-1) yr(-1), respectively. To assess potential influences of high N and S deposition on bogs, we quantified N and S concentrations in tissues of two Sphagnum species, two lichen species, and four vascular plant species, as well as surface porewater concentrations of H(+), NH4(+)-N, NO3(-)-N, SO4(2-)-S and dissolved organic N in 19 ombrotrophic bogs, distributed across a 3255 km(2) sampling area surrounding the oil sands industrial center. The two lichen species (Evernia mesomorpha and Cladonia mitis), two vascular plant species (Rhododendron groenlandicum and Picea mariana), and to a lesser extent one moss (Sphagnum fuscum), showed patterns of tissue N and S concentrations that were (1) highest near the oil sands industrial center and (2) positively correlated with bulk deposition of N or S. Concentrations of porewater H(+) and SO4(2-)-S, but not of NH4(+)-N, NO3(-)-N, DIN, or dissolved inorganic N, also were higher near the oil sands industrial center than at more distant locations. The oil sands region of northern Alberta is remote, with few roads, posing challenges to the monitoring of oil sands-related N and S deposition. Quantification of N

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

    NASA Astrophysics Data System (ADS)

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

    2014-05-01

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

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

    PubMed

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

    2010-09-01

    Radioactive markers are useful in dating lead deposition patterns from industrialization in peat archive. Peat cores were collected in an ombrotrophic peat bog in the Great Hinggan Mountains in Northeast China in September 2008 and dated using (210)Pb and (137)Cs radiometric techniques. The mosses in both cores were examined systematically for dry bulk density, water and ash content. Lead also was measured using atomic emission spectroscopy with inductively coupled plasma (ICP-AES). Both patterned peat profiles were preserved well without evident anthropogenic disturbance. Unsupported (210)Pb and (137)Cs decreased with the depth in both of the two sample cores. The (210)Pb chronologies were established using the constant rate of supply model (CRS) and are in good agreement with the (137)Cs time marker. Recent atmospheric (210)Pb flux in Great Hinggan Mountains peat bog was estimated to be 337 Bq m(-2)y(-1), which is consistent with published data for the region. Lead deposition rate in this region was also derived from these two peat cores and ranged from 24.6 to 55.8 mg m(-2)y(-1) with a range of Pb concentration of 14-262 microg 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.

  5. Uraniferous opal, Virgin Valley, Nevada: conditions of formation and implications for uranium exploration

    USGS Publications Warehouse

    Zielinski, R.A.

    1982-01-01

    Uraniferous, fluorescent opal, which occurs in tuffaceous sedimentary rocks at Virgin Valley, Nevada, records the temperature and composition of uranium-rich solutions as well as the time of uranium-silica coprecipitation. Results are integrated with previous geologic and geochronologic data for the area to produce a model for uranium mobility that may be used to explore for uranium deposits in similar geologic settings. Uraniferous opal occurs as replacements of diatomite, or silicic air-fall ash layers in tuffaceous lakebeds of the Virgin Valley Formation (Miocene) of Merriam (1907). Fission-track radiography shows uranium to be homogeneously dispersed throughout the opal structure, suggesting coprecipitation of dissolved uranium and silica gel. Fluid inclusions preserved within opal replacements of diatomite have homogenization temperatures in the epithermal range and are of low salinity. Four samples of opal from one locality all have U-Pb apparent ages which suggest uraniferous opal precipitation in late Pliocene time. These ages correspond to a period of local, normal faulting, and highangle faults may have served as vertical conduits for transport of deep, thermalized ground water to shallower levels. Lateral migration of rising solutions occurred at intersections of faults with permeable strata. Silica and some uranium were dissolved from silica-rich host strata of 5-20 ppm original uranium content and reprecipitated as the solutions cooled. The model predicts that in similar geologic settings, ore-grade concentrations of uranium will occur in permeable strata that intersect high-angle faults and that contain uranium source rocks as well as efficient reductant traps for uranium. In the absence of sufficient quantities of reductant materials, uranium will be flushed from the system or will accumulate in low-grade disseminated hosts such as uraniferous opal. ?? 1982.

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

    NASA Astrophysics Data System (ADS)

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

    2010-08-01

    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<0.05) owing to increased shading, whereas they increased in deeper peat soil (t-test, p<0.05), probably by enhanced thermal conductivity. RMANOVA suggested interactions between N and PK addition in particular soil layers and strong interactions between soil temperatures and volumetric water contents (p<0.05). Averaged over all 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.

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

    NASA Astrophysics Data System (ADS)

    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 < 0.05) owing to increased shading, whereas they increased in deeper peat soil (t-test, p < 0.05), probably by enhanced thermal conductivity. These effects were confirmed by RMANOVA, which also suggested an influence of volumetric water contents as co-variable on soil temperature and vice versa (p < 0.05). Averaged over all 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.

  8. Inertia in an ombrotrophic bog ecosystem in response to 9 years' realistic perturbation by wet deposition of nitrogen, separated by form.

    PubMed

    Sheppard, Lucy J; Leith, Ian D; Mizunuma, Toshie; Leeson, Sarah; Kivimaki, Sanna; Neil Cape, J; van Dijk, Netty; Leaver, David; Sutton, Mark A; Fowler, David; Van den Berg, Leon J L; Crossley, Alan; Field, Chris; Smart, Simon

    2014-02-01

    Wet deposition of nitrogen (N) occurs in oxidized (nitrate) and reduced (ammonium) forms. Whether one form drives vegetation change more than the other is widely debated, as field evidence has been lacking. We are manipulating N form in wet deposition to an ombrotrophic bog, Whim (Scottish Borders), and here report nine years of results. Ammonium and nitrate were provided in rainwater spray as NH4 Cl or NaNO3 at 8, 24 or 56 kg N ha(-1)  yr(-1) , plus a rainwater only control, via an automated system coupled to site meteorology. Detrimental N effects were observed in sensitive nonvascular plant species, with higher cumulative N loads leading to more damage at lower annual doses. Cover responses to N addition, both in relation to form and dose, were species specific and mostly dependent on N dose. Some species were generally indifferent to N form and dose, while others were dose sensitive. Calluna vulgaris showed a preference for higher N doses as ammonium N and Hypnum jutlandicum for nitrate N. However, after 9 years, the magnitude of change from wet deposited N on overall species cover is small, indicating only a slow decline in key species. Nitrogen treatment effects on soil N availability were likewise small and rarely correlated with species cover. Ammonium caused most N accumulation and damage to sensitive species at lower N loads, but toxic effects also occurred with nitrate. However, because different species respond differently to N form, setting of ecosystem level critical loads by N form is challenging. We recommend implementing the lowest value of the critical load range where communities include sensitive nonvascular plants and where ammonium dominates wet deposition chemistry. In the context of parallel assessment at the same site, N treatments for wet deposition showed overall much smaller effects than corresponding inputs of dry deposition as ammonia.

  9. Bog iron formation in the Nassawango Creek watershed, Maryland, USA

    USGS Publications Warehouse

    Bricker, O.P.; Newell, W.L.; Simon, N.S.; ,

    2004-01-01

    The Nassawango bog ores in the modern environment for surficial geochemical processes were studied. The formation of Nassawango bog ores was suggested to be due to inorganic oxidation when groundwater rich in ferrous iron emerges into the oxic, surficial environment. It was suggested that the process, providing a phosphorus sink, may be an unrecognized benefit for mitigating nutrient loading from agricultural lands. It is found that without the effect of iron fixing bacteria, bog deposites could not form at significant rates.

  10. Historical records of atmospheric Pb deposition in four Scottish ombrotrophic peat bogs: An isotopic comparison with other records from western Europe and Greenland - article no. GB2016

    SciTech Connect

    Cloy, J.M.; Farmer, J.G.; Graham, M.C.; MacKenzie, A.B.; Cook, G.T.

    2008-05-15

    Cores collected from ombrotrophic peat bogs in west central, east central, northeast and southwest Scotland were dated (C-14, Pb-210) and analyzed (ICP-OES, ICP-MS) to derive and compare their historical records of atmospheric anthropogenic Pb deposition over the past 2500 years. On the basis of Pb isotopic composition (e. g., Pb-206/Pb-207), clear indications of Pb contamination during the pre-Roman/Roman, post-Roman and medieval periods were attributed to the mining and smelting of Pb ores from Britain and elsewhere in Europe. Between the 17th and early 20th centuries, during the industrial period, the mining and smelting of indigenous Scottish Pb ores were the most important sources of anthropogenic Pb deposition at three of the sites. In contrast, at the most southerly site, influences from the use of both British Pb ores and imported Australian Pb ores (in more southern parts of Britain) since the late 19th century were evident. At each of the sites, Australian-Pb-influenced car exhaust emissions (from the 1930s to late 1990s), along with significant contributions from coal combustion (until the late 1960s and onset of the post industrial period), were evident. Atmospheric anthropogenic Pb deposition across Scotland was greatest (similar to 10 to 40 mg m{sup -2} a{sup -1}) between the late 1880s and late 1960s, increasing southward, declining to 0.44 to 5.7 mg m{sup 2} a{sup -1} by the early 2000s.

  11. Nature and origins of acidity in bogs

    SciTech Connect

    Urban, N.R.

    1987-01-01

    To elucidate the causes of acidity in bogs, all of the processes generating and consuming acidity in a small peat bog in northern Minnesota were measured. These processes include ion exchange, plant nutrient uptake, atmospheric deposition, decomposition, organic acid production, sulfate reduction, and denitrification. Organic acid production was found to be the dominant source of acidity, responsible for the low pH of bog waters and the high acidity in the outflow. Net biological uptake (NBU) is the next largest source of acidity. Ion exchange accounts for only about 40% of the NBU-acidity. Plant uptake and ion exchange are much larger sources of acidity on an annual basis, but much of this acidity is neutralized by decomposition. Sulfate reduction and denitrification are quantitatively unimportant at this site because inputs (NO/sub 3//sup -/ and SO/sub 4/=) are low. Bog water samples and peat cores from bogs across northeastern North America were analyzed to determine if geographic trends in the rates of acidity-generating and -consuming processes exist. Rates of organic acid production varied little across the transect. Higher values of NBU-acidity were observed in maritime bogs than in midcontinental bogs. The effects of transformations of sulfur and nitrogen on the hydrogen-ion cycle were examined in detail. Nitrate appears to be taken up by bryophytes and little is lost to denitrification. Alkalinity from nitrate uptake is low. In contrast, there is a dynamic cycle of oxidation and reduction of sulfur within bogs. Inorganic forms of sulfur are not important storage pools in peat; 35% of the total sulfur input is accumulated as organic S.

  12. The Vanishing Bog.

    ERIC Educational Resources Information Center

    Hanif, Muhammad

    1990-01-01

    Directions for the construction of a model bog habitat are provided including examples of plants and animals which may be suitable. Activities that use this model are suggested. Background information on the ecology and chemistry of the bog is included. (CW)

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

    NASA Astrophysics Data System (ADS)

    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.

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

    PubMed

    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.

  15. Results of reconnaissance for uraniferous coal, lignite, and carbonaceous shale in western Montana

    USGS Publications Warehouse

    Hail, William James; Gill, James R.

    1953-01-01

    A reconnaissance search for uraniferous lignite and carbonaceous shale was made in western Montana and adjacent parts of Idaho during the summer of 1951. Particular emphasis in the examination was placed on coal and carbonaceous shale associated with volcanic rocks, as volcanic rocks in many areas appear to have released uranium to circulating ground water from which it was ,concentrated in carbonaceous material. Twenty-two areas in Montana and one area in Idaho were examined. The coal in five of these areas is of Cretaceous age. The coal and carbonaceous shale in the remaining 18 areas occur in Tertiary 'fake-bed' deposits of Oligocene and younger age. Both the Cretaceous and Tertiary coal and carbonaceous shale are associated with contemporaneous or younger volcanic rocks and pyrociastic sequences.

  16. Large uraniferous springs and associated uranium minerals, Shirley Mountains, Carbon County, Wyoming -- A preliminary report

    USGS Publications Warehouse

    Love, J.D.

    1963-01-01

    Ten springs along the southeast flank of the Shirley Mountains, Carbon County, Wyoming, have water containing from 12 to 27 parts per billion uranium, have a total estimated flow of 3 million gallons of clear fresh water per day, and have a combined annual output that may be as much as 166 pounds of uranium. These springs emerge from Pennsylvanian, Permian, and Triassic rocks on the east flank of a faulted anticlinal fold. In the vicinity of several springs, metatyuyamunite occurs locally in crystalline calcite veins averaging 3 feet in width but reaching a maximum of 24 feet. The veins are as much as several hundred feet long-and cut vertically through sandstones of Pennsylvanian age overlying the Madison Limestone (Mississippian). This limestone is believed to be the source of the calcite. A 3-foot channel sample cross one calcite vein contains 0.089 percent uranium. Lesser amounts of uranium were obtained from other channel samples. Selected samples contain from 0.39 to 2.2 percent uranium and from 0.25 to 0.86 percent vanadium. Three possible sources of the uranium are: (1) Precambrian rocks, (2) Paleozoic rocks, (3) Pliocene(?) tuffaceous strata that were deposited unconformably across older .rocks in both the graphically high and low parts of the area, but were subsequently removed by erosion except for a few small remnants, one of which contains carnotite. There is apparently a close genetic relation between the uraniferous springs and uranium mineralization in the calcite veins. Data from this locality illustrate how uraniferous ground water can be used as a guide in the exploration for areas where uranium deposits may occur. Also demonstrated is the fact that significant quantities of uranium are present in water of some large flowing springs.

  17. Investigating Bogs: An Interdisciplinary Adventure.

    ERIC Educational Resources Information Center

    Pankiewicz, Philip R.; Schneider, Lois

    1995-01-01

    Presents the case for the use of bogs as ideal sites for hundreds of interdisciplinary lessons that combine chemistry, geology, various branches of biology, and wetlands archaeology. Includes general guidelines to aid in the design of interdisciplinary bog studies. (DDR)

  18. Differences in cancer mortality rates in Ohio communities with respect to uraniferous geology

    SciTech Connect

    Dzik, A.J.

    1989-07-01

    Populations in areas of uraniferous geology may be at risk from radon emissions. Twenty-eight municipalities were examined as to their location with respect to uraniferous geology. Communities with possible radon risk had higher rates for all cancers and cancer of the respiratory system, but differences were not statistically significant. Some possible reasons for the results are discussed.

  19. 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.

    NASA Astrophysics Data System (ADS)

    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.

  20. Results of reconnaissance for uraniferous coal, lignite, and carbonaceous shale in western Montana

    USGS Publications Warehouse

    Hail, William J.; Gill, James R.

    1952-01-01

    A reconnaissance search for uraniferous lignite and carbonaceous shale was made in western Montana and adjacent parts of Idaho during the summer of 1951. Particular emphasis in the examination was placed on coal and carbonaceous shale associated with volcanic rocks, as volcanic rocks in many area appear to have released uranium to circulating ground water from which it was concentrated in carbonaceous material. Twenty-two area in Montana and one area of Idaho were examine. The coal in five of these area is of Cretaceous age. The coal and carbonaceous shale in the remaining 18 area occur in Tertiary "lake-bed" deposits of Oligocene and younger age. Both the Cretaceous and Tertiary coal and carbonaceous shale are associated with contemporaneous or younger volcanic rocks and pyroclastic sequences. A sample of carbonaceous shale from the Prickly Pear Valley northeast of Helena, Montana, contained 0.013 percent uranium. A sample of carbonaceous shale from the Flint Creek Valley southwest of Drummond, Montana, contained 0.006 percent uranium. All other samples of both Cretaceous and Tertiary coal and carbonaceous shale were essentially non-radioactive. No further work is planned on the Cretaceous and Tertiary coal and carbonaceous shale in western Montana. A few localities in Idaho will be visited in the course of other work.

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

    PubMed Central

    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

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

    PubMed

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

    2015-07-01

    We applied a (15)N 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).

  3. Pre- and syn-ore zonation in Precambrian uraniferous sodic metasomatities

    SciTech Connect

    Omel'yanenko, B.I.; Mineyeva, I.G.

    1982-04-01

    Uraniferous-sodic metasomatites in Precambrian basement faults, in which a regular change in the mineral composition in vertical section has been established are described. The authors attempt to show that this pattern is controlled by the evolution of the solutions in time and space, and that it is an expression of a verticle metasomatic zonation. (JMT)

  4. 137Cs in a raised bog in central Sweden.

    PubMed

    Rosén, K; Vinichuk, M; Johanson, K J

    2009-07-01

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

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

    NASA Astrophysics Data System (ADS)

    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.

  6. U-Pb ages of uraniferous opals and implications for the history of beryllium, fluorine, and uranium mineralization at Spor Mountain, Utah

    USGS Publications Warehouse

    Ludwig, K. R.; Lindsey, D.A.; Zielinski, R.A.; Simmons, K.R.

    1980-01-01

    The U-Pb isotope systematics of uraniferous opals from Spor Mountain, Utah, were investigated to determine the suitability of such material for geochronologic purposes, and to estimate the timing of uranium and associated beryllium and fluorine mineralization. The results indicate that uraniferous opals can approximate a closed system for uranium and uranium daughters, so that dating samples as young as ???1 m.y. should be possible. In addition, the expected lack of initial 230Th and 231Pa in opals permits valuable information on the initial 234U/238U to be obtained on suitable samples of ???10 m.y. age. The oldest 207Pb/235U apparent age observed, 20.8 ?? 1 m.y., was that of the opal-fluorite core of a nodule from a beryllium deposit in the Spor Mountain Formation. This age is indistinguishable from that of fission-track and K-Ar ages from the host rhyolite, and links the mineralization to the first episode of alkali rhyolite magmatism and related hydrothermal activity at Spor Mountain. Successively younger ages of 13 m.y. and 8-9 m.y. on concentric outer zones of the same nodule indicate that opal formed either episodically or continuously for over 10 m.y. Several samples of both fracture-filling and massive-nodule opal associated with beryllium deposits gave 207Pb/235U apparent ages of 13-16 m.y., which may reflect a restricted period of mineralization or perhaps an averaging of 21- and <13-m.y. periods of opal growth. Several samples of fracture-filling opal in volcanic rocks as young as 6 m.y. gave 207Pb/235U ages of 3.4-4.8 m.y. These ages may reflect hot-spring activity after the last major eruption of alkali rhyolite. ?? 1980.

  7. Consequences of marginal drainage from a raised bog and understanding the hydrogeological dynamics as a basis for restoration

    NASA Astrophysics Data System (ADS)

    Regan, Shane; Johnston, Paul

    2010-05-01

    of vertical water losses in the peat profile not confined to the bog margins. Distinct zones of groundwater seepage in the marginal drains have been mapped based on hydrochemical and stable isotopic composition of the water and occur where drains have cut into permeable subsoil beneath the peat substrate and where the potentiometric surface of the regional groundwater table is below, or coincident with, the elevation at the base of the drain. Groundwater as a ‘supporting' ecological condition is usually confined to the perimeter of a raised bog, where peat and underlying clay thin towards the margin, allowing regional groundwater and peat water to converge and mix, thereby giving rise to characteristic nutrient rich ‘lagg' zone vegetation. However, in Clara Bog West it appears there is also a connection between the regional groundwater table and the high bog. Such a connection appears to be unique to Clara Bog West as a result of the prevailing geological conditions. A succession of Carboniferous Limestone to relatively permeable glacial till deposits to low permeability lacustrine clay sediment is the predominant underlying geology of the bog. However, there are areas where the glacial till protrudes through the lacustrine clay, which ordinarily isolates the high bog from underlying groundwater, thereby engendering a dependency on regional groundwater conditions. The hydrogeological data now suggest that drainage at the bog margin has created a hydraulic connection between these ‘subsoil subcrops' and the marginal drains, developed within the same subsoil, thereby lowering the regional groundwater table, steepening the hydraulic gradient and resulting in significant water loss from the main bog body. As such, understanding this hydrogeological connection is central to restoration activities that will aim to arrest subsidence and restore water levels that are indicative for ecotope development, on the high bog. Acknowledgements Clara Restoration Group: Jan

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

    NASA Astrophysics Data System (ADS)

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

    NASA Astrophysics Data System (ADS)

    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

  10. Paired charcoal and tree-ring records of high-frequency Holocene fire from two New Mexico bog sites

    USGS Publications Warehouse

    Allen, C.D.; Anderson, R. Scott; Jass, R.B.; Toney, J.L.; Baisan, C.H.

    2008-01-01

    Two primary methods for reconstructing paleofire occurrence include dendrochronological dating of fire scars and stand ages from live or dead trees (extending back centuries into the past) and sedimentary records of charcoal particles from lakes and bogs, providing perspectives on fire history that can extend back for many thousands of years. Studies using both proxies have become more common in regions where lakes are present and fire frequencies are low, but are rare where high-frequency surface fires dominate and sedimentary deposits are primarily bogs and wetlands. Here we investigate sedimentary and fire-scar records of fire in two small watersheds in northern New Mexico, in settings recently characterised by relatively high-frequency fire where bogs and wetlands (Chihuahuen??os Bog and Alamo Bog) are more common than lakes. Our research demonstrates that: (1) essential features of the sedimentary charcoal record can be reproduced between multiple cores within a bog deposit; (2) evidence from both fire-scarred trees and charcoal deposits documents an anomalous lack of fire since ???1900, compared with the remainder of the Holocene; (3) sedimentary charcoal records probably underestimate the recurrence of fire events at these high-frequency fire sites; and (4) the sedimentary records from these bogs are complicated by factors such as burning and oxidation of these organic deposits, diversity of vegetation patterns within watersheds, and potential bioturbation by ungulates. We consider a suite of particular challenges in developing and interpreting fire histories from bog and wetland settings in the Southwest. The identification of these issues and constraints with interpretation of sedimentary charcoal fire records does not diminish their essential utility in assessing millennial-scale patterns of fire activity in this dry part of North America. ?? IAWF 2008.

  11. [Metagenomics and biodiversity of sphagnum bogs].

    PubMed

    Rusin, L Yu

    2016-01-01

    Biodiversity of sphagnum bogs is one of the richest and less studied, while these ecosystems are among the top ones in ecological, conservation, and economic value. Recent studies focused on the prokaryotic consortia associated with sphagnum mosses, and revealed the factors that maintain sustainability and productivity of bog ecosystems. High-throughput sequencing technologies provided insight into functional diversity of moss microbial communities (microbiomes), and helped to identify the biochemical pathways and gene families that facilitate the spectrum of adaptive strategies and largely foster the very successful colonization of the Northern hemisphere by sphagnum mosses. Rich and valuable information obtained on microbiomes of peat bogs sets off the paucity of evidence on their eukaryotic diversity. Prospects and expectations of reliable assessment of taxonomic profiles, relative abundance of taxa, and hidden biodiversity of microscopic eukaryotes in sphagnum bog ecosystems are briefly outlined in the context of today's metagenomics.

  12. Estimating methane production rates in bogs and landfills by deuterium enrichment of pore water

    USGS Publications Warehouse

    Siegel, D.I.; Chanton, J.P.; Glaser, P.H.; Chasar, L.S.; Rosenberry, D.O.

    2001-01-01

    Raised bogs and municipal waste landfills harbor large populations of methanogens within their domed deposits of anoxic organic matter. Although the methane emissions from these sites have been estimated by various methods, limited data exist on the activity of the methanogens at depth. We therefore analyzed the stable isotopic signature of the pore waters in two raised bogs from northern Minnesota to identify depth intervals in the peat profile where methanogenic metabolism occurs. Methanogenesis enriched the deuterium (2H) content of the deep peat pore waters by as much as +11% (Vienna Standard Mean Sea Water), which compares to a much greater enrichment factor of +70% in leachate from New York City's Fresh Kills landfill. The bog pore waters were isotopically dated by tritium (3H) to be about 35 years old at 1.5 m depth, whereas the landfill leachate was estimated as ~ 17 years old from Darcy flow calculations. According to an isotopic mass balance the observed deuterium enrichment indicates that about 1.2 g of CH4m-3 d-1 were produced within the deeper peat, compared to about 2.8 g CH4 m-3 d-1 in the landfill. The values for methane production in the bog peat are substantially higher than the flux rates measured at the surface of the bogs or at the landfill, indicating that deeper methane production may be much higher than was previously assumed.

  13. Uranium deposits at Shinarump Mesa and some adjacent areas in the Temple Mountain district, Emery County, Utah

    USGS Publications Warehouse

    Wyant, Donald G.

    1953-01-01

    Deposits of uraniferous hydrocarbons are associated with carnotite in the Shinarump conglomerate of Triassic age at Shinarump Mesa and adjacent areas of the Temple Mountain district in the San Rafael Swell of Emery County, Utah. The irregular ore bodies of carnotite-bearing sandstone are genetically related to lenticular uraniferous ore bodies containing disseminated asphaltitic and humic hydrocarbon in permeable sandstones and were localized indirectly by sedimentary controls. Nearly non-uraniferous bitumen commonly permeates the sandstones in the Shinarump conglomerate and the underlying Moekopi formation in the area. The ore deposits at Temple Mountain have been altered locally by hydrothermal solutions, and in other deposits throughout the area carnotite has been transported by ground and surface water. Uraniferous asphaltite is thought to be the non-volatile residue of an original weakly uraniferous crude oil that migrated into the San Rafael anticline; the ore metals concentrated in the asphaltite as the oil was devolatilized and polymerized. Carnotite is thought to have formed from the asphaltite by ground water leaching. It is concluded that additional study of the genesis of the asphaltitic uranium ores in the San Rafael Swell, of the processes by which the hydrocarbons interact and are modified (such as heat, polymerization, and hydrogenation under the influence of alpha-ray bombardment), of petroleum source beds, and of volcanic intrusive rocks of Tertiary age are of fundamental importance in the continuing study of the uranium deposits on the Colorado Plateau.

  14. Response of douglas fir (Pseudotsuga menziesii) to uraniferous groundwater in a small glaciated drainage, Northeastern Washington State

    USGS Publications Warehouse

    Zielinski, R.A.; Schumann, R.R.

    1987-01-01

    Douglas fir trees and associated soils were sampled from the slopes of a small (??? 4 km2) drainage basin in northeastern Washington to investigate the biogeochemical response to locally uraniferous groundwater. Uranium is preferentially incorporated in needles and twigs compared to larger branches or the trunk. The U concentration in needle ash ranges from 0.2 to 5.8 ??g g-1 (ppm) and shows no correlation with the U concentration in associated soils. Rather, the distribution of anomalously uraniferous douglas fir (>1.0??g g-1 U in needle ash) appears to be controlled by observed or readily inferred pathways of near-surface groundwater movement in the drainage. These pathways include: (1) general downslope movement of subsurface runoff; (2) increased flux of near-surface groundwater near the toe of an alluvial fan; and (3) emergence of uraniferous (100-150 ng ml-1 [ppb] groundwater in the vicinity of a slope spring. The data also indicate the presence of near-surface uraniferous groundwater along a structurally controlled zone that parallels the north-south strike of the valley, and that includes the slope spring. The results suggest that biogeochemical sampling may be used to supplement more direct, but more limited, measurements of groundwater quality and flow regime in areas of near-surface contaminated groundwater. ?? 1987.

  15. Response of douglas fir (Pseudotsuga menziesii) to uraniferous groundwater in a small glaciated drainage, Northeastern Washington State

    USGS Publications Warehouse

    Zielinski, R.A.; Schumann, R.R.

    1987-01-01

    Douglas fir trees and associated soils were sampled from the slopes of a small (???4 km2) drainage basin in northeastern Washington to investigate the biogeochemical response to locally uraniferous groundwater. Uranium is preferentially incorporated in needles and twigs compared to larger branches or the trunk. The U concentration in needle ash ranges from 0.2 to 5.8??g g-1 (ppm) and shows no correlation with the U concentration in associated soils. Rather, the distribution of anomalously uraniferous douglas fir (> 1.0??g g-1 U in needle ash) appears to be controlled by observed or readily inferred pathways of near-surface groundwater movement in the drainage. These pathways include: (1) general downslope movement of subsurface runoff; (2) increased flux of near-surface groundwater near the toe of an alluvial fan; and (3) emergence of uraniferous (100-150 ng ml-1 [ppb] groundwater in the vicinity of a slope spring. The data also indicate the presence of near-surface uraniferous groundwater along a structurally controlled zone that parallels the north-south strike of the valley, and that includes the slope spring. The results suggest that biogeochemical sampling may be used to supplement more direct, but more limited, measurements of groundwater quality and flow regime in areas of near-surface contaminated groundwater. ?? 1987.

  16. Titanium in ombrotrophic Sphagnum mosses from various peat bogs of Germany and Belgium.

    PubMed

    Kempter, Heike; Frenzel, Burkhard

    2008-03-25

    Titanium concentrations and Ti inventories (total Ti in the sample) in living Sphagnum mosses from the surfaces of eight ombrotrophic peat bogs of five different regions of Germany and Belgium were studied over a period of two years (1995-7). Six to ten peat moss samples with a given surface area (100 cm2) and length (5 cm) were collected at different sites in the peat bogs studied several times (every six weeks to three months) during a year. Variability of Ti concentrations and inventories were determined within each peat bog for the species S. magellanicum, S. rubellum, S. papillosum, and S. cuspidatum, for the microhabitats 'lawn', 'slope' and 'hollow', as well as for the studied peat bogs of different regions and for each season. Likewise, Ti concentration values were determined for the moss plant segments: 'capitulum', 'living green' and 'dead brown'. Ti concentrations and inventories were found to be highly variable, even in one species of the same peat bog and at the same time. Moreover, median Ti concentrations and inventories of different species and microhabitats were quite similar to one another. As a result, we suggest that more productive species might be able to accumulate more Ti onto their bigger surface areas than the less productive ones. Besides, Ti particles might be transported downwards with the water and accumulated by the mosses over a longer time period than only one year. To reliably specify the variations in the geochemistry of peat mosses on the peat bog surface the annual production of each collected Sphagnum sample has to be exactly known and samples of equal ages and time periods they were exposed to atmospheric deposition have to be studied.

  17. Atmospheric carbonyl sulfide exchange in bog microcosms

    SciTech Connect

    Fried, A.; Klinger, L.F.; Erickson, D.J. III )

    1993-01-22

    Measurements of Carbonyl sulfide (OCS) fluxes were carried out on bog microcosms using chamber sampling and tunable diode laser analysis. Intact bog microcosms (vascular plants, mosses, and peat) removed ambient levels of OCS in the light and dark with rates from [minus]2.4 to [minus]8.1 ng S min[sup [minus]1] m[sup [minus]2]. Peat and peat plus mosses emitted OCS in the light with rates of 17.4 and 10.9 ng S min[sup [minus]1] m[sup [minus]2], respectively. In the dark, the mosses apparently removed OCS at a rate equivalent to the peat emissions. A 3-D numerical tracer model using this data indicated that boreal bog ecosystems remove at most 1% of ambient OCS, not sufficient to account for an observed OCS depletion in boreal air masses. 13 refs., 1 fig., 1 tab.

  18. 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

    USGS Publications Warehouse

    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

  19. Effect of mineral constituents in the bioleaching of uranium from uraniferous sedimentary rock samples, Southwestern Sinai, Egypt.

    PubMed

    Amin, Maisa M; Elaassy, Ibrahim E; El-Feky, Mohamed G; Sallam, Abdel Sattar M; Talaat, Mona S; Kawady, Nilly A

    2014-08-01

    Bioleaching, like Biotechnology uses microorganisms to extract metals from their ore materials, whereas microbial activity has an appreciable effect on the dissolution of toxic metals and radionuclides. Bioleaching of uranium was carried out with isolated fungi from uraniferous sedimentary rocks from Southwestern Sinai, Egypt. Eight fungal species were isolated from different grades of uraniferous samples. The bio-dissolution experiments showed that Aspergillus niger and Aspergillus terreus exhibited the highest leaching efficiencies of uranium from the studied samples. Through monitoring the bio-dissolution process, the uranium grade and mineralogic constituents of the ore material proved to play an important role in the bioleaching process. The tested samples asserted that the optimum conditions of uranium leaching are: 7 days incubation time, 3% pulp density, 30 °C incubation temperature and pH 3. Both fungi produced the organic acids, namely; oxalic, acetic, citric, formic, malonic, galic and ascorbic in the culture filtrate, indicating an important role in the bioleaching processes.

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

    NASA Astrophysics Data System (ADS)

    Glatzel, S.; Forbrich, I.; 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 mesocosms from the center and edge before, during, and following a drainage experiment as well as carbon dioxide release from disturbed unfertilized and nitrogen fertilized surface peat. In the field, methane fluxes ranged from 0 to 3.8 mg m-2 h-1 and were highest from hollows. Field nitrous oxide fluxes ranged from 0 to 574 μg m-2 h-1 and were elevated at the edge. A large Eriophorum vaginatum tussock showed decreasing nitrous oxide release as the season progressed. Drainage of mesocosms decreased methane release to 0, even during rewetting. There was a tendency for a decrease of nitrous oxide release during drainage and for an increase in nitrous oxide release during rewetting. Nitrogen fertilization did not increase decomposition of surface peat. Our examinations suggest a competition between vascular vegetation and denitrifiers for excess nitrogen. We also provide evidence that the von Post humification index can be used to explain greenhouse gas release from bogs, if the role of vascular vegetation is also considered. An assessment of the greenhouse gas release from nitrogen saturated restoring bogs needs to take into account elevated release from fresh Sphagnum peat as well as from sedges growing on decomposed peat. Given the high atmospheric nitrogen deposition, restoration will not be able to achieve an oligotrophic ecosystem in the short term.

  1. [Methanotrophic bacteria of acid sphagnum bogs].

    PubMed

    Dedysh, S N

    2002-01-01

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

  2. 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)

    NASA Astrophysics Data System (ADS)

    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.

  3. Mineralogy and geochemistry of a uraniferous coal from the Red Desert Area, Sweetwater County, Wyoming

    USGS Publications Warehouse

    Breger, Irving A.; Deul, Maurice; Meyrowitz, Robert; Rubinstein, Samuel

    1953-01-01

    A sample of subbituminous uraniferous coal from the Red Desert, Sweetwater County, Wyo., was studied mineralogically. The coal contains gypsum (6 percent), kaolinite (1 percent), quartz (0.3 percent), calcite (trace), and limonite (trace). This suite of minerals and the absence of pyrite show that the coal has been subjected to weathering and oxidation. No uranium minerals have been found; mechanical fractionation has indicated that the uranium is associated with the organic constituents of the coal. The minerals that have been isolated contain 0.0006 percent uranium, a content which is to be expected for nonuraniferous sedimentary rocks. The organic components of the coal contain approximately 0.002 percent uranium. On the basis of material balance calculations, the organic components carry 98 percent of the uranium in the coal. Fischer assays of this weathered coal from the Red Desert indicate a yield of 16.7 gallons of tar per ton on low-temperature retorting. In view of the large reserve of subbituminous coal in the Red Desert, its probable ease of mining, and its tar yield, it may be desirable to carry out further evaluation of the coal as a fuel or raw material for the manufacture of tar or chemicals. If economic factors permit utilization of the coal, the uranium, although present in small percentages, could be recovered as a byproduct.

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

    NASA Astrophysics Data System (ADS)

    Shotyk, William

    2013-04-01

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

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

    NASA Astrophysics Data System (ADS)

    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

  6. Environmental assessment of remedial action at the inactive uraniferous lignite processing sites at Belfield and Bowman, North Dakota. [UMTRA Project

    SciTech Connect

    Beranich, S.; Berger, N.; Bierley, D.; Bond, T.M.; Burt, C.; Caldwell, J.A.; Dery, V.A.; Dutcher, A.; Glover, W.A.; Heydenburg, R.J.; Larson, N.B.; Lindsey, G.; Longley, J.M.; Millard, J.B.; Miller, M.; Peel, R.C.; Persson-Reeves, C.H.; Titus, F.B.; Wagner, L.

    1989-09-01

    The Uranium Mill Tailings Radiation Control Act of 1978 (UMTRCA), to clean up the Belfield and Bowman, North Dakota, uraniferous lignite processing sites to reduce the potential health impacts associated with the residual radioactive materials remaining at these sites. Remedial action at these sites must be performed in accordance with the US Environmental Protection Agency's (EPA) standards promulgated for the remedial action and with the concurrence of the US Nuclear Regulatory Commission (NRC) and the state of North Dakota. The inactive Belfield uraniferous lignite processing site is one mile southeast of Belfield, North Dakota. The inactive Bowman uraniferous lignite processing site at the former town of Griffin, is seven miles northwest of Bowman, North Dakota and 65 road miles south of Belfield. Lignite ash from the processing operations has contaminated the soils over the entire 10.7-acre designated Belfield site and the entire 12.1-acre designated Bowman site. Dispersion of the ash has contaminated an additional 20.6 acres surrounding the Belfield processing site and an additional 59.2 acres surrounding the Bowman processing site. The proposed remedial action is to relocate the contaminated materials at the Belfield processing site to the Bowman processing/disposal site for codisposal with the Bowman contaminated soils. The environmental impacts assessed in this EA were evaluated for the proposed remedial action and the no action alternative and demonstrate that the proposed action would not significantly affect the quality of the human environment and would be performed in compliance with applicable environmental laws. The no action alternative would not be consistent with the intent of Public Law 95-604 and would not comply with the EPA standards. 48 refs., 10 figs., 7 tabs.

  7. Isotopic evidence for nitrogen mobility in peat bogs

    NASA Astrophysics Data System (ADS)

    Novak, Martin; Stepanova, Marketa; Jackova, Ivana; Vile, Melanie A.; Wieder, R. Kelman; Buzek, Frantisek; Adamova, Marie; Erbanova, Lucie; Fottova, Daniela; Komarek, Arnost

    2014-05-01

    Elevated nitrogen (N) input may reduce carbon (C) storage in peat. Under low atmospheric deposition, most N is bound in the moss layer. Under high N inputs, Sphagnum is not able to prevent penetration of dissolved N to deeper peat. Nitrogen may become available to the roots of invading vascular plants. The concurrent oxygenation of deeper peat layers, along with higher supply of labile organic C, may enhance microbial decomposition and lead to peat thinning. The resulting higher emissions of greenhouse gases may accelerate global warming. Seepage of N to deeper peat has never been quantified. Here we present evidence for post-depositional mobility of atmogenic N in peat, based on natural-abundance N isotope ratios. We conducted a reciprocal peat transplant experiment between two Sphagnum-dominated peat bogs in the Czech Republic (Central Europe), differing in anthropogenic N inputs. The northern site VJ received as much as 33 kg N ha-1 yr-1 via spruce canopy throughfall. The southern site was less polluted (17.6 kg N ha-1 yr-1). Isotope signatures of living moss differed between the two sites (δ15N of -3‰ and -7‰ at VJ and CB, respectively). After 18 months, an isotope mass balance was constructed. In the CB-to-VJ transplant, a significant portion of original CB nitrogen (98-31%) was removed and replaced by nitrogen of the host site throughout the top 10 cm of the profile. Nitrogen, deposited at VJ, was immobilized in imported CB peat that was up to 20 years old. Additionally, we compared N concentration and N accumulation rates in 210Pb-dated peat profiles with well-constrained data on historical atmospheric N pollution. Nationwide N emissions peaked in 1990, while VJ exhibited the highest N content in peat that formed in 1930. This de-coupling of N inputs and N retention in peat might be interpreted as a result of translocation of dissolved pollutant N downcore, corroborating our δ15N results at VJ and CB. Data from a variety of peat bogs along pollution

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

    PubMed

    Hill, Brian H; Jicha, Terri M; Lehto, LaRae L P; Elonen, Colleen M; Sebestyen, Stephen D; Kolka, Randall K

    2016-04-15

    We compared nitrogen (N) storage and flux in soils from an ombrotrophic bog with that of a minerotrophic fen to quantify the differences in N cycling between these two peatlands types in northern Minnesota (USA). Precipitation, atmospheric deposition, and bog and fen outflows were analyzed for nitrogen species. Upland and peatland soil samples were analyzed for N content, and for ambient (DN) and potential (DEA) denitrification rates. Annual atmospheric deposition was: 0.88-3.07kg NH4(+)ha(-1)y(-1); 1.37-1.42kg NO3(-)ha(-1)y(-1); 2.79-4.69kg TNha(-1)y(-1). Annual N outflows were: bog-0.01-0.04kg NH4(+)ha(-1)y(-1), NO3(-) 0.01-0.06kgha(-1)y(-1), and TN 0.11-0.69kgha(-1)y(-1); fen-NH4(+) 0.01-0.16kgha(-1)y(-1), NO3(-) 0.29-0.48kgha(-1)y(-1), and TN 1.14-1.61kgha(-1)y(-1). Soil N content depended on location within the bog or fen, and on soil depth. DN and DEA rates were low throughout the uplands and peatlands, and were correlated with atmospheric N deposition, soil N storage, and N outflow. DEA was significantly greater than DN indicating C or N limitation of the denitrification process. We highlight differences between the bog and fen, between the upland mineral soils and peat, and the importance of biogeochemical hotspots within the peatlands. We point out the importance of organic N storage, as a source of N for denitrification, and propose a plausible link between organic N storage, denitrification and N export from peatlands. Finally, we considered the interactions of microbial metabolism with nutrient availability and stoichiometry, and how N dynamics might be affected by climate change in peatland ecosystems.

  9. Bog breath: Sleeper factor in global warming?

    SciTech Connect

    Benyus, J.M.

    1995-04-01

    This artical examines the emission of gases from northern peatlands as plants grow and decay and its implication in the global increase in greenhouse gases, particularly carbon dioxide and methane. Bogs do extract carbon dioxide from the air, incorporating it into green plants which become buried for a long time. However, the cold, wet conditions are ideal for microbes which emit methane. Global climate change models indicate that Minnesota, for example will be 5 degrees warmer and somewhat wetter in future years. As a result bacterial metabolism and methane generation may increase considerably. This paper discusses current research and speculation and looks at possible solutions, both man-created and natural.

  10. Geoinformatics meets education for a peat bog information system

    NASA Astrophysics Data System (ADS)

    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.

  11. Baseline risk assessment of ground water contamination at the inactive uraniferous lignite ashing site near Bowman, North Dakota

    SciTech Connect

    Not Available

    1994-11-01

    This baseline risk assessment of ground water contamination at the inactive uraniferous lignite ashing site near Bowman, North Dakota, evaluates the potential impacts to public health or the environment from contaminated ground water at this site. This contamination is a result of the uraniferous lignite ashing process, when coal containing uranium was burned to produce uranium. Potential risk is quantified only for constituents introduced by the processing activities and not for the constituents naturally occurring in background ground water in the site vicinity. Background ground water, separate from any site-related contamination, imposes a percentage of the overall risk from ground water ingestion in the Bowman site vicinity. The US Department of Energy (DOE) Uranium Mill Tailings Remedial Action (UMTRA) Project is developing plans to address soil and ground water contamination at the site. The UMTRA Surface Project involves the determination of the extent of soil contamination and design of an engineered disposal cell for long-term storage of contaminated materials. The UMTRA Ground Water Project evaluates ground water contamination. Based on results from future site monitoring activities as defined in the site observational work plan and results from this risk assessment, the DOE will propose an approach for managing contaminated ground water at the Bowman site.

  12. Nest-site characteristics of Glyptemys muhlenbergii (Bog Turtle) in New Jersey and Pennsylvania

    USGS Publications Warehouse

    Zappalorti, Robert T.; Lovich, Jeffrey E.; Farrell, Ray F.; Torocco, Michael E.

    2015-01-01

    Nest-site selection can affect both the survival and fitness of female turtles and their offspring. In many turtle species, the nest environment determines the thermal regime during incubation, length of incubation period, sex ratio of the hatchlings, and exposure to predators and other forms of mortality for both mothers and their offspring. Between 1974 and 2012, we collected detailed data on habitat variables at 66 Glyptemys muhlenbergii (Bog Turtle) nests in 9 different bogs, fens, and wetland complexes in New Jersey and Pennsylvania. The nests had a mean elevation above the substrate of 8.2 cm, and many were shallow and located in raised tussocks of grass or sedges. Females covered most nests, but we also observed partially or completely uncovered eggs. Some females deposited eggs in communal nests; we found 4 nests with 2 separate clutches, and 2 nests with 3 clutches. Principal component analysis confirmed the importance of cover and vegetation to nest-site selection in this species. Availability of open, shade-free, wet nesting areas is an important habitat requirement for Bog Turtles.

  13. Experimental study on performance of BOG compressor

    NASA Astrophysics Data System (ADS)

    Zhao, Bin; Wang, Tao; Peng, Xueyuan; Feng, Jianmei

    2015-08-01

    The boil-off gas (BOG) compressor is widely used for recycling the excessive boil-off gas of liquefied natural gas (LNG), and the extra-low suction temperature brings about great challenges to design of the BOG compressor. In this paper, a test system was built to examine the effects of low suction temperature on the compressor performance, in which the lowest temperature reached -178°C by means of a plate-fin heat exchanger with liquefied nitrogen. The test results showed that, as the suction temperature decreased from 20°C to -150°C, the volumetric efficiency of the compressor dropped by 37.0%, and the power consumption decreased by 10.0%. The preheat of the gas by the pipe through the suction flange to suction valve was larger than 20°C as the suction temperature was -150°C, and this value increased with the decreased suction temperature. The pressure loss through the suction valve at lower suction temperature was larger than that at ambient temperature while the volume flow rate was kept the same.

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

    NASA Astrophysics Data System (ADS)

    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

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

    NASA Astrophysics Data System (ADS)

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

    2014-02-01

    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 ten kilometers, they share the same 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 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 two years (July 2010 to 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 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 LAI 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, if the whole life-cycle, since forest planting is considered. We determined the difference between carbon fixation by the spruces and the carbon loss from the peat due to drainage since forest planting. The estimate resulted in a strong carbon release of +156 t C ha-1 within the last 44 yr, means the spruces would need to grow for another 100 yr, at the current rate, to compensate the peat loss of the former years. In contrast, the natural bog-pine ecosystem has likely been a small but consistent carbon sink for decades, which our results suggest is very robust regarding short

  16. Uranium accumulation in aquatic macrophytes in an uraniferous region: Relevance to natural attenuation.

    PubMed

    Cordeiro, Cristina; Favas, Paulo J C; Pratas, João; Sarkar, Santosh Kumar; Venkatachalam, Perumal

    2016-08-01

    Phytoremediation potential of uranium (U) was investigated by submerged, free-floating and rooted emergent native aquatic macrophytes inhabiting along the streams of Horta da Vilariça, a uraniferous geochemical region of NE Portugal. The work has been undertaken with the following objectives: (i) to relate the U concentrations in water-sediment-plant system; and (ii) to identify the potentialities of aquatic plants to remediate U-contaminated waters based on accumulation pattern. A total of 25 plant species culminating 233 samples was collected from 15 study points along with surface water and contiguous sediments. Concentrations of U showed wide range of variations both in waters (0.61-5.56 μg L(-1), mean value 1.98 μg L(-1)) and sediments (124-23,910 μg kg(-1), mean value 3929 μg kg(-1)) and this is also reflected in plant species examined. The plant species exhibited the ability to accumulate U several orders of magnitude higher than the surrounding water. Maximum U concentrations was recorded in the bryophyte Scorpiurium deflexifolium (49,639 μg kg(-1)) followed by Fontinalis antipyretica (35,771 μg kg(-1)), shoots of Rorippa sylvestris (33,837 μg kg(-1)), roots of Oenanthe crocata (17,807 μg kg(-1)) as well as in Nasturtium officinale (10,995 μg kg(-1)). Scorpiurium deflexifolium displayed a high bioconcentration factor (BF) of ∼2.5 × 10(4) (mean value). The species Fontinalis antipyretica, Nasturtium officinale (roots) and Rorippa sylvestris (shoots) exhibited the mean BFs of 1.7 × 10(4), 5 × 10(3) and 4.8 × 10(3) respectively. Maximum translocation factor (TF) was very much pronounced in the rooted perennial herb Rorippa sylvestris showing extreme ability to transport U for the shoots and seems to be promising candidate to be used as bioindicator species.

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

    NASA Astrophysics Data System (ADS)

    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.

  18. A hydrological study of Waen y Griafolen blanket bog, North Wales

    NASA Astrophysics Data System (ADS)

    Hall, G.

    2010-12-01

    Many mountain rivers in North Wales have their headwaters in peat blanket bogs. An example is Waen y Griafolen, source area for the Afon Mawddach, which formed the focus of a hydrological study by Bangor University over the period 2002-2004. Fieldwork has been supplemented by groundwater and surface water modelling. The blanket bog covers an area of approximately 6 km2 within a plateau basin in Lower Paleozoic shales. The structure of the blanket bog is complex. Erica and Trichophorum vegetation communities occupy the central area of the bog on deposits of old humified peat. Eroded into the old peat surface is a system of bifurcating channels occupied by actively accumulating Juncus and Sphagnum communities. River gravel and lake clay were found beneath the active peat channels at depths of several metres, indicative of an earlier and more extensive surface drainage system eroded into the bog surface. A palaeosoil occurs at the base of the old humified peat, with tree roots identified as Salix in growth position. A sample has been dated as 8905 ± 45 years before the reference year AD 1950. Waen y Griafolen has developed over the past 9000 years since the last ice sheets receded from upland Britain. Peat erosion represented by the buried river channels and lake bed may be linked to a period of increased rainfall across Europe at around 2600 years before the present. Groundwater levels have been continuously monitored at an instrumented borehole in the centre of the bog. It is found that the older humified peats have a surprisingly low water storage capacity and may become saturated during a single storm event. Storm flow occurs predominantly through fast surface runoff into the Juncus and Sphagnum infilled channels, where slow lateral movement takes place towards open stream courses at the basin outlet. There appears to be little vertical water movement into the underlying impermeable Ordovician shales. Climate change with an increase in winter rainfall may promote

  19. Radioactive waste disposal in simulated peat bog repositories

    SciTech Connect

    Schell, W.R.; Massey, C.D.

    1987-01-01

    The Low Level Radioactive Waste Policy Act of 1980 and the Low Level Radioactive Waste Policy Amendments Act of 1985 have required state governments to be responsible for providing low-level waste (LLW) disposal facilities in their respective areas. Questions are (a) is the technology sufficiently advanced to ensure that radioactive wastes can be stored for 300 to 1000 yr without entering into any uncontrolled area. (b) since actual experience does not exist for nuclear waste disposal over this time period, can the mathematical models developed be tested and verified using unequivocal data. (c) how can the public perception of the problem be addressed and the potential risk assessment of the hazards be communicated. To address the technical problems of nuclear waste disposal in the acid precipitation regions of the Northern Hemisphere, a project was initiated in 1984 to evaluate an alternative method of nuclear waste disposal that may not rely completely on engineered barriers to protect the public. Certain natural biogeochemical systems have been retaining deposited materials since the last Ice Age (12,000 to 15,000 yr). It is the authors belief that the biogeochemical system of wetlands and peat bogs may provide an example of an analogue for a nuclear waste repository system that can be tested and verified over a sufficient time period, at least for the LLW disposal problem.

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

    PubMed

    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.

  1. The Limits to Peat Bog Growth

    NASA Astrophysics Data System (ADS)

    Clymo, R. S.

    1984-01-01

    Not less than 2% of the Earth's land surface is peat-covered, so it is important to try to understand the dynamics of peat accumulation. Peat-forming systems (mires) accumulate peat because conditions within them impede the decay of the plant material produced by their surface vegetation. This paper concerns the rate of peat production and some unexpected consequences of the processes of decay. These consequences are likely to be of interest to those concerned with mire ecology and with the history of vegetation during Flandrian times. Most peat-forming systems consist of two layers: an upper 10-50 cm deep aerobic layer of high hydraulic conductivity, the acrotelm, in which the rate of decay is relatively high; and a thicker, usually anaerobic, lower layer, the catotelm, of low conductivity and with a much lower rate of decay. Plant structure at the base of the acrotelm collapses as a consequence of aerobic decay, and the hydraulic conductivity consequently decreases. As long as precipitation continues the water table therefore rises to this level, thus engulfing material at the base of the acrotelm. The rate, p_c, of this input to the catotelm is exactly analogous to the rate, p_a, of input to the acrotelm i.e. of primary productivity of the vegetation. During passage through the acrotelm the peat becomes richer in the more slowly decaying components. The depth of, and the time for transit through, the acrotelm thus control p_c. The catotelm, however, usually forms much the largest part of the peat mass. Selective decay may continue in the catotelm. The specific composition of the peat thus becomes a progressively poorer indicator of the surface vegetation that formed it, and to a degree that is not generally realized: reconstructions of the past surface vegetation may become very inaccurate. If p_c were constant and there were no decay in the catotelm then for the centre of a peat bog the profile of age against depth (measured as cumulative mass below the surface

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

    EPA Science Inventory

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

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

    NASA Astrophysics Data System (ADS)

    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

  4. Biogeochemistry of aquatic humic substances in Thoreau's Bog, Concord, Massachusetts

    USGS Publications Warehouse

    McKnight, Diane; Thurman, E. Michael; Wershaw, Robert L.; Hemond, Herold

    1985-01-01

    Thoreau's Bog is an ombrotrophic floating—mat Sphagnum bog developed in a glacial kettlehole and surrounded by a red maple swamp. Concentrations of dissolved organic carbon in the porewater of the bog average 36 mg/L and are greatest near the surface, especially during late summer. This distribution suggest that the upper layer of living and dead Sphagnum and moderately humified peat is the major site of dissolved organic material production in the bog. The dissolved organic material consists mainly of aquatic fulvic acid (67%) and hydrophilic acids (20%); these organic acids control the pH (typically 4 or somewhat lower) of the bogwater. The elemental, amino acid, carbohydrate, and carboxylic acid contents of fulvic acid from the bog are similar to those of aquatic fulvic acid from the nearby Shawsheen River, although the phenolic hydroxyl content of fulvic acid from Thoreau's Bog is higher. The hydrophilic acids have greater amino acid, carbohydrate, and carboxylic acid contents than the fulvic acid, consistent with the hypothesis that hydrophilic acids are more labile intermediate compounds in the formation of fulvic acid.

  5. Effects of nutrient addition on leaf chemistry, morphology, and photosynthetic capacity of three bog shrubs.

    PubMed

    Bubier, Jill L; Smith, Rose; Juutinen, Sari; Moore, Tim R; Minocha, Rakesh; Long, Stephanie; Minocha, Subhash

    2011-10-01

    Plants in nutrient-poor environments typically have low foliar nitrogen (N) concentrations, long-lived tissues with leaf traits designed to use nutrients efficiently, and low rates of photosynthesis. We postulated that increasing N availability due to atmospheric deposition would increase photosynthetic capacity, foliar N, and specific leaf area (SLA) of bog shrubs. We measured photosynthesis, foliar chemistry and leaf morphology in three ericaceous shrubs (Vaccinium myrtilloides, Ledum groenlandicum and Chamaedaphne calyculata) in a long-term fertilization experiment at Mer Bleue bog, Ontario, Canada, with a background deposition of 0.8 g N m(-2) a(-1). While biomass and chlorophyll concentrations increased in the highest nutrient treatment for C. calyculata, we found no change in the rates of light-saturated photosynthesis (A(max)), carboxylation (V(cmax)), or SLA with nutrient (N with and without PK) addition, with the exception of a weak positive correlation between foliar N and A(max) for C. calyculata, and higher V(cmax) in L. groenlandicum with low nutrient addition. We found negative correlations between photosynthetic N use efficiency (PNUE) and foliar N, accompanied by a species-specific increase in one or more amino acids, which may be a sign of excess N availability and/or a mechanism to reduce ammonium (NH(4)) toxicity. We also observed a decrease in foliar soluble Ca and Mg concentrations, essential minerals for plant growth, but no change in polyamines, indicators of physiological stress under conditions of high N accumulation. These results suggest that plants adapted to low-nutrient environments do not shift their resource allocation to photosynthetic processes, even after reaching N sufficiency, but instead store the excess N in organic compounds for future use. In the long term, bog species may not be able to take advantage of elevated nutrients, resulting in them being replaced by species that are better adapted to a higher nutrient environment.

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

    PubMed

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

    2012-05-01

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

  7. Lead isotope ratios in bone ash of blesbok (Damaliscus pygargus phillipsi): a means of screening for the accumulation of contaminants from uraniferous rocks.

    PubMed

    Nöthling, Johan O; Du Toit, Johannes S; Myburgh, Jan G

    2014-09-19

    This study was done to determine whether blesbok (Damaliscus pygargus phillipsi) from the Krugersdorp Game Reserve (KGR) in Gauteng Province, South Africa have higher concentrations of (238)U and higher (206)Pb/(204)Pb and (207)Pb/(204)Pb ratios in their bone ash than blesbok from a nearby control reserve that is not exposed to mine water and has no outcrops of uraniferous rocks. Eight blesbok females from the KGR and seven from the control site, all killed with a brain shot, were used. A Thermo X-series 2 quadrupole ICPMS was used to measure the concentrations of (238)U and lead and a Nu Instruments NuPlasma HR MC-ICP-MS to measure the lead isotope ratios in the tibial ash from each animal. KGR blesbok had higher mean concentrations of (238)U (P = 0.02) and ratios of (206)Pb/(204)Pb and (207)Pb/(204)Pb (P < 0.00001) than the control blesbok. The probability of rejecting the false null hypothesis of no difference in the (206)Pb/(204)Pb or (207)Pb/(204)Pb ratios between KGR and control reserve animals (the power of the test) was 0.999. The blesbok from the KGR accumulated contaminants from an uraniferous environment. The (206)Pb/(204)Pb and (207)Pb/(204)Pb ratios in tibial ash proved effective in confirming accumulation of contaminants from uraniferous rocks.

  8. Hydrologic conditions in Connors Bog Area, Anchorage, Alaska

    USGS Publications Warehouse

    Glass, R.L.

    1986-01-01

    Connors Bog is a wetland in Anchorage, Alaska, which provides a habitat for many wildlife species and is a popular area for driving off-road vehicles. A landfill, and residential and commercial developments are present in areas which were once wetland. The main source of water is precipitation, which averages about 15 in/yr. Estimates of evapotranspiration, which is the main component of water outflow, range from 10 to 20 in/yr. Minor amounts of groundwater and surface runoff flow into the area from the northeast and southwest and flow out of the area to the northwest and south. Within the wetland, water in peat and sand is unconfined and becomes more mineralized with depth. A leachate beneath and near an abandoned landfill is characterized by concentrations of dissolved solids, dissolved chloride, and total organics that are higher than those of the area 's natural water. The maximum lateral extent of detectable contamination in 1984 was < 500 ft from the landfill 's edge. Water in glacial deposits that underlie a poorly permeable layer of silt and clay is confined. A well completed in this confined aquifer yielded water that had a low concentration of dissolved solids, 150 mg/L. The potentiometric surface of this aquifer was about 20 ft lower than the water table during 1984. Connors Lake occupies a depression that extends below adjacent groundwater levels. The 40-acre lake has a maximum depth of about 9 ft and a low rate of biological production. The quality of water in the lake has not been adversely impacted by nearby residential development or landfill operations. Lake levels appear to be influenced by precipitation and adjacent groundwater levels. (Author 's abstract)

  9. Soil data for a collapse-scar bog chronosequence in Koyukuk Flats National Wildlife Refuge, Alaska, 2008

    USGS Publications Warehouse

    O’Donnell, Jonathan A.; Harden, Jennifer W.; Manies, Kristen L.; Jorgenson, M. Torre

    2012-01-01

    Peatlands in the northern permafrost region store large amounts of organic carbon, most of which is currently stored in frozen peat deposits. Recent warming at high-latitudes has accelerated permafrost thaw in peatlands, which will likely result in the loss of soil organic carbon from previously frozen peat deposits to the atmosphere. Here, we report soil organic carbon inventories, soil physical data, and field descriptions from a collapse-scar bog chronosequence located in a peatland ecosystem at Koyukuk Flats National Wildlife Refuge in Alaska.

  10. Significant nonsymbiotic nitrogen fixation in Patagonian ombrotrophic bogs.

    PubMed

    Knorr, Klaus-Holger; Horn, Marcus A; Borken, Werner

    2015-06-01

    Nitrogen (N) nutrition in pristine peatlands relies on the natural input of inorganic N through atmospheric deposition or biological dinitrogen (N2 ) fixation. However, N2 fixation and its significance for N cycling, plant productivity, and peat buildup are mostly associated with the presence of Sphagnum mosses. Here, we report high nonsymbiotic N2 -fixation rates in two pristine Patagonian bogs with diversified vegetation and natural N deposition. Nonsymbiotic N2 fixation was measured in samples from 0 to 10, 10 to 20, and 40 to 50 cm depth using the (15) N2 assay as well as the acetylene reduction assay (ARA). The ARA considerably underestimated N2 fixation and can thus not be recommended for peatland studies. Based on the (15) N2 assay, high nonsymbiotic N2 -fixation rates of 0.3-1.4 μmol N2  g(-1)  day(-1) were found down to 50 cm under micro-oxic conditions (2 vol.%) in samples from plots covered by Sphagnum magellanicum or by vascular cushion plants, latter characterized by dense and deep aerenchyma roots. Peat N concentrations point to greater potential of nonsymbiotic N2 fixation under cushion plants, likely because of the availability of easily decomposable organic compounds and oxic conditions in the rhizosphere. In the Sphagnum plots, high N2 fixation below 10 cm depth rather reflects the potential during dry periods or low water level when oxygen penetrates the top peat layer and triggers peat mineralization. Natural abundance of the (15) N isotope of live Sphagnum (5.6 δ‰) from 0 to 10 cm points to solely N uptake from atmospheric deposition and nonsymbiotic N2 fixation. A mean (15) N signature of -0.7 δ‰ of peat from the cushion plant plots indicates additional N supply from N mineralization. Our findings suggest that nonsymbiotic N2 fixation overcomes N deficiency in different vegetation communities and has great significance for N cycling and peat accumulation in pristine peatlands.

  11. Vegetation feedbacks of nutrient addition lead to a weaker carbon sink in an ombrotrophic bog.

    PubMed

    Larmola, Tuula; Bubier, Jill L; Kobyljanec, Christine; Basiliko, Nathan; Juutinen, Sari; Humphreys, Elyn; Preston, Michael; Moore, Tim R

    2013-12-01

    To study vegetation feedbacks of nutrient addition on carbon sequestration capacity, we investigated vegetation and ecosystem CO2 exchange at Mer Bleue Bog, Canada in plots that had been fertilized with nitrogen (N) or with N plus phosphorus (P) and potassium (K) for 7-12 years. Gross photosynthesis, ecosystem respiration, and net CO2 exchange were measured weekly during May-September 2011 using climate-controlled chambers. A substrate-induced respiration technique was used to determine the functional ability of the microbial community. The highest N and NPK additions were associated with 40% less net CO2 uptake than the control. In the NPK additions, a diminished C sink potential was due to a 20-30% increase in ecosystem respiration, while gross photosynthesis rates did not change as greater vascular plant biomass compensated for the decrease in Sphagnum mosses. In the highest N-only treatment, small reductions in gross photosynthesis and no change in ecosystem respiration led to the reduced C sink. Substrate-induced microbial respiration was significantly higher in all levels of NPK additions compared with control. The temperature sensitivity of respiration in the plots was lower with increasing cumulative N load, suggesting more labile sources of respired CO2 . The weaker C sink potential could be explained by changes in nutrient availability, higher woody : foliar ratio, moss loss, and enhanced decomposition. Stronger responses to NPK fertilization than to N-only fertilization for both shrub biomass production and decomposition suggest that the bog ecosystem is N-P/K colimited rather than N-limited. Negative effects of further N-only deposition were indicated by delayed spring CO2 uptake. In contrast to forests, increased wood formation and surface litter accumulation in bogs seem to reduce the C sink potential owing to the loss of peat-forming Sphagnum.

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

    NASA Astrophysics Data System (ADS)

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

    2012-04-01

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

  13. Acidophilic Methanotrophic Communities from Sphagnum Peat Bogs

    PubMed Central

    Dedysh, Svetlana N.; Panikov, Nicolai S.; 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 arranged in aggregates with a minor contribution of Hyphomicrobium-like cells. The growth stoichiometry of isolates was characteristic of methanotrophic bacteria (CH4/O2/CO2=1:1.1:0.59), with an average apparent yield of 0.41 ± 0.03 g of biomass C/g of CH4-C. DNA from each enrichment yielded a PCR product of the expected size with primers for both mmoX and mmoY genes of soluble methane monooxygenase. Two types of sequences were obtained for PCR-amplified fragments of mmoX. One of them exhibited high identity to the mmoX protein of the Methylocystis-Methylosinus group, whereas the other showed an equal level of divergence from both the Methylosinus-Methylocystis group and Methylococcus capsulatus (Bath) and formed a distinct branch. The pH optimum for growth and for CH4 uptake was 4.5 to 5.5, which is very similar to that for the optimum CH4 uptake observed in the original peat samples. These methanotrophs are moderate acidophiles rather than acidotolerant organisms, since their growth rate and methane uptake were much lower at neutral pH. The growth of the methanotrophic community was enhanced by using media with a very low salt content (20 to 200 mg/liter), more typical of their natural environment. All four enriched communities grew on N-free medium. PMID:9501432

  14. 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

    NASA Astrophysics Data System (ADS)

    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

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

    NASA Astrophysics Data System (ADS)

    Mezhibor, A. M.

    2016-11-01

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

  16. Tracing of ca 800 yr old mining activity in peat bog using Pb elemental concentrations and isotope compositions.

    NASA Astrophysics Data System (ADS)

    Baron, S.; Carignan, J.; Ploquin, A.

    2003-04-01

    Sixty sites of slags have been documented on the Mont-Lozère in southern France. The petrographic analysis shows that slags are metallurgical wastes (800 to 850 yr BP) which certainly result from smelting activity for lead and silver extraction (Ploquin et al., 2001). The aims of this study are: 1) to trace the source of Pb ores which supplied the smelting sites, by using the Pb isotopic composition of several surrounding Pb deposits, 2) to evaluate the actual pollution caused by these slags, by using elemental and isotopic compositions of soils, water and vegetation, and 3) to document the pollution history of the region, by using elemental and isotopic compositions of peat bog cores collected in the neighbourhood of the historical smelting sites. The lead isotopic composition of galena collected in most surrounding ores is very similar to that of different slag samples. On the other hand, the high precision of the results allowed us to select the mineralised areas which were probably the ore sources. The Pb isotopic composition of slags is even more homogeneous: 208/206 Pb: 2.092±0.002; 206/207 Pb: 1.179±0.001; 208/204 Pb: 38.663±0.025; 207/204 Pb: 15.665±0.006; 206/204 Pb: 18.476±0.023, and will allow source tracing in the environment. The "Narses Mortes" peat bog, around which two smelting sites have been reported, is strongly minerotrophic and contains 8 to 60% ash. A 1.40 m core have been retrieved and divided into 58 individual samples. Minerotrophic peat bog records both atmospheric deposition, soils leaching and the grounwater influence. The measured metal concentrations are normalised to Al contents of peat bog samples and the metal/Al ratios are compared to that of the Mont-Lozère granite: relative excess in metal concentrations are found in peat bog samples. An increasing excess of most metals (Pb, Zn, Cd...) was measured for surface samples, from 55 cm depth to the top of the core (23 cm depth). This profil might be attributed to atmospheric

  17. The aqueous geochemistry of uranium in a drainage containing uraniferous organic-rich sediments, Lake Tahoe area, Nevada, USA

    USGS Publications Warehouse

    Zielinski, R.A.; Otton, J.K.; Wanty, R.B.; Pierson, C.T.

    1988-01-01

    Anomalously uraniferous waters occur in a small (4.2 km2) drainage in the west-central Carson Range, Nevada, on the eastern side of Lake Tahoe. The waters transport uranium from local U-rich soils and bedrock to organic-rich valley-fill sediments where it is concentrated, but weakly bound. The dissolved U and the U that is potentially available from coexisting sediments pose a threat to the quality of drinking water that is taken from the drainage. The U concentration in samples of 6 stream, 11 spring and 7 near-surface waters ranged from 0.1 V). Possible precipitation of U(IV) minerals is predicted under the more reducing conditions that are particularly likely in near-surface waters, but the inhibitory effects of sluggish kinetics or organic complexing are not considered. These combined results suggest that a process such as adsorption or ion exchange, rather than mineral saturation, is the most probable mechanism for uranium fixation in the sediments. -Authors

  18. Environmental assessment of remedial action at the inactive uraniferous lignite ashing sites at Belfield and Bowman, North Dakota

    SciTech Connect

    Not Available

    1993-09-01

    The Uranium Mill Tailings Radiation Control Act (UMTRCA) of 1978 authorized the US Department of Energy (DOE) to perform remedial actions at Belfield and Bowman inactive lignite ashing sites in southwestern North Dakota to reduce the potential public health impacts from the residual radioactivity remaining at the sites. The US Environmental Protection Agency (EPA) promulgated standards (40 CFR 192) that contain measures to control the residual radioactive materials and other contaminated materials, and proposed standards to protect the groundwater from further degradation. Remedial action at the Belfield and Bowman sites must be performed in accordance with these standards and with the concurrence of the US Nuclear Regulatory Commission (NRC) and the state of North Dakota. The Belfield and Bowman designated sites were used by Union Carbide and Kerr-McGee, respectively, to process uraniferous lignite in the 1960s. Uranium-rich ash from rotary kiln processing of the lignite was loaded into rail cars and transported to uranium mills in Rifle, Colorado, and Ambrosia Lake, New Mexico, respectively. As a result of the ashing process, there is a total of 158,400 cubic yards (yd{sup 3}) [121,100 cubic meters (m{sup 3})] of radioactive ash-contaminated soils at the two sites. Windblown ash-contaminated soil covers an additional 21 acres (8.5 ha) around the site, which includes grazing land, wetlands, and a wooded habitat.

  19. Environmental assessment of no remedial action at the inactive uraniferous lignite ashing sites at Belfield and Bowman, North Dakota

    SciTech Connect

    1997-06-01

    The Belfield and Bowman sites were not included on the original congressional list of processing sites to be designated by the Secretary of Energy. Instead, the sites were nominated for designation by the Dakota Resource Council in a letter to the DOE (September 7, 1979). In a letter to the DOE (September 12, 1979), the state of North Dakota said that it did not believe the sites would qualify as processing sites under the Uranium Mill Tailings Radiation Control Act (UMTRCA) because the activities at the sites involved only the ashing of uraniferous lignite coal and the ash was shipped out of state for actual processing. Nevertheless, on October 11, 1979, the state of North Dakota agreed to the designation of the sites because they met the spirit of the law (reduce public exposure to radiation resulting from past uranium operations). Therefore, these sites were designated by the Secretary of Energy for remedial action. Because of the relatively low health impacts determined for these sites, they were ranked as low priority and scheduled to be included in the final group of sites to be remediated.

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

    PubMed

    Antonović, Ivan; Brigić, Andreja; Sedlar, Zorana; Bedek, Jana; Soštarić, Renata

    2012-01-01

    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.

  1. Remediation System Evaluation, Bog Creek Farm Superfund Site

    EPA Pesticide Factsheets

    The Bog Creek Farm Superfund site is located in Howell Township, Monmouth County, New Jersey onCounty Road 547. The site is bordered by two residences to the west, the north branch of SquankumBrook to the north, and open fields to the south and east.

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

    NASA Astrophysics Data System (ADS)

    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.

  3. Storage and behavior of As, Sb, Pb, and Cu in ombrotrophic peat bogs under contrasting water table conditions.

    PubMed

    Rothwell, James J; Taylor, Kevin G; Chenery, Simon R N; Cundy, Andrew B; Evans, Martin G; Allott, Timothy E H

    2010-11-15

    Concentration depth profiles and inventories of solid-phase As, Sb, Pb, and Cu were determined in ²¹⁰Pb-dated cores from an ombrotrophic peat bog in northwest England. Cores were collected from the peat dome and adjacent to an eroding gully. Down-core distributions of As, Sb, Pb, and Cu in the dome core are almost identical. The water table is close to the dome surface with only short-term draw-down. Under these conditions, As, Sb, Pb, and Cu are immobile, allowing the reconstruction of trends in historical contaminant deposition. The peak in atmospheric deposition of As, Sb, Pb, and Cu (4.59, 2.78, 147, and 26.7 mg m⁻² y⁻¹, respectively) occurred during the late 19th century. Stable Pb isotope ratios reveal that Pb deposition during this period was from indigenous and foreign sources. The mean water table is much lower at the gully edge, and there are pronounced interannual fluctuations. These conditions have not affected the integrity of the Pb and Cu records but have caused postdepositional mobilization and redistribution of As and Sb. Cumulative inventories show significant loss of As and Sb at the gully edge site. Long-term water table draw-down in ombrotrophic peat bogs has the potential to alter the geochemistry and fate of previously deposited As and Sb.

  4. Reconnaissance for uraniferous rocks in northwestern Colorado, southwestern Wyoming, and northeastern Utah

    USGS Publications Warehouse

    Beroni, E.P.; McKeown, F.A.

    1952-01-01

    Previous discoveries and studies of radioactive lignites of Tertiary age in North Dakota, South Dakota, Montana, and Wyoming led the Geological Survey in 1950 to do reconnaissance in the Green River and Uinta Basin of Wyoming and Utah, where similar lignites were believed to be present. Because of the common association of uranium with copper deposits and the presence of such deposits in the Uinta Basin, several areas containing copper-uranium minerals were also examined. No deposits commercially exploitable under present conditions were found. Samples of coal from the Bear River formation at Sage, Wyo., assayed 0.004 to 0.013 percent uranium in the ash; in the old Uteland copper mine in Uinta County, Utah, 0.007 to 0.017 percent uranium; in a freshwater limestone, Duchesne County, Utah, as much as 0.019 percent uranium; and in the Mesaverde formation at the Snow and Bonniebell claims near Jensen, Uintah County, Utah, 0.003 to 0.090 percent uranium. Maps were made and samples were taken at the Skull Creek carnotite deposits in Moffat County, Colo. (0.006 to 0.16 percent uranium); at the Fair-U claims in Routt County, Colo. (0.002 to 0.040 percent uranium); and at the Lucky Strike claims near Kremmling in Grand County, Colo. (0.006 to 0.018 percent uranium).

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

    PubMed

    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.

  6. Predominant anthropogenic sources and rates of atmospheric mercury accumulation in southern Ontario recorded by peat cores from three bogs: comparison with natural "background" values (past 8000 years).

    PubMed

    Givelet, Nicolas; Roos-Barraclough, Fiona; Shotyk, William

    2003-12-01

    Peat cores from three bogs in southern Ontario provide a complete, quantitative record of net rates of atmospheric Hg accumulation since pre-industrial times. For comparison with modern values, a peat core extending back 8000 years was used to quantify the natural variations in Hg fluxes for this region, and their dependence on climatic change and land use history. The net mercury accumulation rates were separated into "natural" and "excess" components by comparing the Hg/Br ratios of modern samples with the long-term, pre-anthropogenic average Hg/Br. The average background mercury accumulation rate during the pre-anthropogenic period (from 5700 years BC to 1470 AD) was 1.4 +/- 1.0 microg m(-2) per year (n = 197). The beginning of Hg contamination from anthropogenic sources dates from AD 1475 at the Luther Bog, corresponding to biomass burning for agricultural activities by Native North Americans. During the late 17th and 18th centuries, deposition of anthropogenic Hg was at least equal to that of Hg from natural sources. Anthropogenic inputs of Hg to the bogs have dominated continuously since the beginning of the 19th century. The maximum Hg accumulation rates decrease in the order Sifton Bog, in the City of London, Ontario (141 microg Hg m(-2) per year), Luther Bog in an agricultural region (89 microg Hg m(-2) per year), and Spruce Bog which is in a comparatively remote, forested region (54 microg Hg m(-2) per year). Accurate age dating of recent peat samples using the bomb pulse curve of 14C shows that the maximum rate of atmospheric Hg accumulation occurred during AD 1956 and 1959 at all sites. In these (modern) samples, the Hg concentration profiles resemble those of Pb, an element which is known to be immobile in peat bogs. The correlation between these two metals, together with sulfur, suggests that the predominant anthropogenic source of Hg (and Pb) was coal burning. While Hg accumulation rates have gone into strong decline since the late 1950's, Hg

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

    NASA Astrophysics Data System (ADS)

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

    2016-04-01

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

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

    NASA Astrophysics Data System (ADS)

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

    2016-04-01

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

  9. 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

    NASA Astrophysics Data System (ADS)

    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.

  10. Stages of litter transformation in bog birch forests

    NASA Astrophysics Data System (ADS)

    Efremova, T. T.; Avrova, A. F.; Efremov, S. P.; Melent'eva, N. V.

    2009-10-01

    In the litters (peaty, weakly decomposed, and strongly decomposed) of bog birch forests, the biochemical transformation of plant material includes several discrete stages. The best prediction of the decomposition stages is the set of indices characterizing the humus status of the soils: the C/N ratio, (ΣHA + ΣFA)/Cpolysaccharides, and the contents of humic and fulvic acids of fraction 1 in the groups of plant debris of different sizes. The discrimination of the litters according to the level of the biochemical transformation of the organic residues was observed when using the (ΣHA + ΣFA)/Cpolysaccharides ratio, which is 6.3 in the peaty litter and 11.2 and 18.4 in the weakly decomposed and strongly decomposed litters, respectively. The biochemical classification of litters in the bog birch forests is in agreement with the morphological classification of litters.

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

    PubMed

    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.

  12. Carbon and Water Cycles in a New Zealand Peat Bog

    NASA Astrophysics Data System (ADS)

    Campbell, D.; Smith, J.

    2001-12-01

    Peat soils represent globally significant stores of carbon and an understanding of carbon exchange processes between peat wetland ecosystems and the atmosphere is important for understanding the effects of, and impacts upon, global climate change. Eddy covariance measurements of CO2, water vapour and energy fluxes were made during 1999 and 2000 at a remnant oligotrophic raised peat bog in North Island, New Zealand. The bog's hydrology has been modified by drainage of surrounding agricultural land, so that the water table is relatively deep compared to that of unmodified bogs in the region. Vegetation is dominated by two indigenous species of rush-like vascular plants belonging to the Southern hemisphere family Restionaceae. Maximum daytime CO2 fluxes were commonly -9 {μ }mol m-2 s-1 and averaged -1.3 {μ }mol m-2 s-1 over the 24-hour period in summertime. The ecosystem was a sink of atmospheric carbon for most of the year, with wintertime characterised by 12--15 weeks of carbon neutrality or slight carbon loss. Average carbon uptake by the ecosystem was 196 gC m-2 yr-1 for the two-year period. Modelling suggests that the key factor determining inter-annual variability of the carbon budget is seasonal soil temperature, whereas ecosystem respiration is relatively insensitive to the position of the lowered water table. The bog vegetation acts as a major control over water vapour loss and energy partitioning favors sensible heat production with mean summertime Bowen ratios of approximately 2.0. Water use efficiency was highest in the morning, indicating that the vegetation maximizes CO2 assimilation while the saturation vapour pressure deficit and transpiration rates are low. The dense canopy structure also restricts penetration of solar radiation to the peat surface, which minimizes evaporation and soil respiration.

  13. Properties and structure of raised bog peat humic acids

    NASA Astrophysics Data System (ADS)

    Klavins, Maris; Purmalis, Oskars

    2013-10-01

    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 profiles, and to study peat humification impact 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 structures 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 process of living organic matter. Concentrations of carboxyl and phenolic hydroxyl groups change depending on the peat age and decomposition degree from where HAs have been isolated, and carboxylic acidity of peat HAs increases with peat depth and humification degree.

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

    NASA Astrophysics Data System (ADS)

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

    2016-12-01

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

  15. Utilization of bog iron ores as sorbents of heavy metals.

    PubMed

    Rzepa, Grzegorz; Bajda, Tomasz; Ratajczak, Tadeusz

    2009-03-15

    Sorption properties of bog iron ores with respect to Pb, Cu, Zn, Cr are evaluated at various pH. Maximum sorption determined in the experiments equals to 97.0, 25.2, 25.5, 55.0mg/g for lead(II), copper(II), zinc(II), and chromium(III), respectively. Chromium(VI) is bound in the amount of up to 10.0mg/g. The values of desorption indicate that most of the metals remain stably bound to the surface of bog iron ores, indicating that the chemisorption process prevails. The metals are sorbed as cations at the pH values from 4 to 9. Within this pH range up to 100% of the initial metal amount is immobilized. 90-100% of Cr(VI) is sorbed at pH between 3 and 5. Such properties, combined with favorable conditions of shallow mining and resultant low costs, may be regarded as an incentive for local utilization of bog iron ores in the environmental protection practice.

  16. Animal and vegetation patterns in natural and man-made bog pools: implications for restoration

    USGS Publications Warehouse

    Mazerolle, M.J.; Poulin, M.; Lavoie, C.; Rochefort, L.; Desrochers, A.; Drolet, B.

    2006-01-01

    1. Peatlands have suffered great losses following drainage for agriculture, forestry, urbanisation, or peat mining, near inhabited areas. We evaluated the faunal and vegetation patterns after restoration of a peatland formerly mined for peat. We assessed whether bog pools created during restoration are similar to natural bog pools in terms of water chemistry, vegetation structure and composition, as well as amphibian and arthropod occurrence patterns. 2. Both avian species richness and peatland vegetation cover at the site increased following restoration. Within bog pools, however, the vegetation composition differed between natural and man-made pools. The cover of low shrubs, Sphagnum moss, submerged, emergent and floating vegetation in man-made pools was lower than in natural pools, whereas pH was higher than in typical bog pools. Dominant plant species also differed between man-made and natural pools. 3. Amphibian tadpoles, juveniles and adults occurred more often in man-made pools than natural bog pools. Although some arthropods, including Coleoptera bog specialists, readily colonised the pools, their abundance was two to 26 times lower than in natural bog pools. Plant introduction in bog pools, at the stocking densities we applied, had no effect on the occurrence of most groups. 4. We conclude that our restoration efforts were partially successful. Peatland-wide vegetation patterns following restoration mimicked those of natural peatlands, but 4 years were not sufficient for man-made pools to fully emulate the characteristics of natural bog pools.

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

    NASA Astrophysics Data System (ADS)

    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.

  18. Geology and recognition criteria for uranium deposits of the quartz-pebble conglomerate type. Final report

    SciTech Connect

    Button, A.; Adams, S.S.

    1981-03-01

    This report is concerned with Precambrian uraniferous conglomerates. This class of deposit has been estimated to contain between approximately 16 and 35 percent of the global uranium reserve in two rather small areas, one in Canada, the other in South Africa. Similar conglomerates, which are often gold-bearing, are, however, rather widespread, being found in parts of most Precambrian shield areas. Data have been synthesized on the geologic habitat and character of this deposit type. The primary objective has been to provide the most relevant geologic observations in a structural fashion to allow resource studies and exploration to focus on the most prospective targets in the shortest possible time.

  19. Geochemical evidence for the hydrology of a Tamarack-peat bog, Brimfield Township, Portage County, Ohio

    SciTech Connect

    Wilson, T.P.; Miller, L.A. . Dept. of Geology and Water Resources)

    1992-01-01

    Peat Bogs and wetlands represent unique environmental settings what are increasingly subjected to anthropogenic stresses involving inputs of water and chemicals. This study used geochemical and hydrologic monitoring to determine the inputs and fates of elements of the Kent-Brimfield bog located in Portage County, Ohio. Based on physical and chemical information collected over one year, a model is proposed here describing the hydrologic connection between a bog and shallow ground water surrounding the bog. The chemical composition of precipitation, soil water and ground water in the bog vicinity were monitored for one year. Field measurements included water levels, pH, Eh, alkalinity and temperature. Trace metal content of the peat, the pore waters, soil water and ground waters were determined by GFAA, ICP and LIC methods. This bog was found to function as part of a perched water table aquifer. Water in the upper 3 m of the bog is found to be chemically similar to precipitation, but modified by reactions involving dissolution of mineral matter and biologic processes. The chemistry of water deeper in the bog (> 3m) resembles shallow ground water surrounding the bog, modified by weathering of underlying geologic materials and sulfate reduction. This similarity, along with ground water elevations within and outside of the bog, supports that shallow ground water interacts with, and helps maintain water levels in the upper surface of the bog. From these results, a model is proposed for the seasonal variations in hydrologic processes operating in the wetland and surrounding basin, and describes how wetlands may change seasonally from being influent to effluent systems.

  20. Influence of uraniferous black shales on cadmium, molybdenum and selenium in soils and crop plants in the Deog-Pyoun-g area of Korea.

    PubMed

    Kim, K W; Thornton, I

    1993-09-01

    The influence of naturally occurring uraniferous black shales on cadmium, molybdenum and selenium concentrations in soils and plants is examined. The possible implications of element concentrations to animal and human health are considered for the Deog-Pyoung area.Geochemical surveys have been undertaken within 13 river tributary valleys in the area underlain by uraniferous black shales and black slates or grey chlorite schists. Sampling of rocks, soils and plants has been carried out along transect lines within each valley. Samples were analysed for trace elements by Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES) and for uranium by Neutron Activation Analysis (NAA). Soil pH, cation exchange capacity, loss on ignition and particle size distribution have been measured for selected samples.Average trace element concentrations of the Okchon uraniferous black shales were 6.3 μg g(-1) Cd, 136 μg g(-1) Mo and 8.6 μg g(-1) Se. Soils derived from these rocks tend to reflect their extreme geochemical composition. Trace element concentrations in alluvial soils derived in part from these black shales averaged 1.2 μg g(-1) Cd, 20 μg g(-1) Mo and 1.5 μg g(-1) Se. Trace element concentrations in plants were found to be influenced by those of soils. Cadmium accumulated in tobacco leaves up to 46 μg g(-1) (D.M.) and leafy plants such as lettuce contain up to 0.5 μg g(-1) Se (D.M.).In addition to total concentrations in soils, soil pH is a major factor influencing uptake of Mo into crop plants and soil texture for Se. Concentrations of trace elements in plants also varied between plant species. The relative concentrations of Cd were found to vary in the order tobacco > lettuce > red pepper > rice grain.Elevated concentrations of Cd in crop plants and in tobacco may possibly have deleterious effects on human health in this area. The low Cu:Mo ratio in rice stalk of 2.65:1 may be associated with disturbed Cu metabolism in ruminant animals which regularly

  1. The bog landforms of continental western Canada in relation to climate and permafrost patterns

    SciTech Connect

    Vitt, D.H.; Halsey, L.A. ); Zoltai, S.C. )

    1994-02-01

    In continental western Canada, discontinuous permafrost is almost always restricted to ombrotrophic peatlands (bogs). Bogs occur mostly as islands or peninsulas in large, often complex fens or are confined to small basins. Permafrost may be present in extensive peat plateaus (or more locally as palsas) and was preceded by a well-developed layer of Sphagnum that served to insulate the peat and lower the pore water temperatures. Air photo interpretation reveals the occurrence of bogs with five types of surface physiography. Concentrated to the south are bogs without internal patterns that have never had permafrost. Dominating the mid-latitudes are bogs with internal lawns and fens with internal lawns (mostly representing former bogs) that had permafrost lenses in the past that have recently degraded. Concentrated in the northwest are peat plateaus without internal lawns or distinct collapse scars, but with permafrost; dominating in the northernmost area are peat plateaus with extensive permafrost and collapse scars. Relationships are apparent between the current - 1[degrees]C isotherm and the southern occurrence of peat plateaus and between the 0[degrees]C isotherm and the southern edge of bogs and fens with internal lawns. We interpret bogs and fens with internal lawns to represent areas where permafrost degradation is currently occurring at a greater rate than aggradation, seemingly in response to warmer regional climate, although fire frequency may also be of local importance. 54 refs., 21 figs., 2 tabs.

  2. Genesis of peat-bog soils in the northern taiga spruce forests of the Kola Peninsula

    SciTech Connect

    Nikonov, V.V.

    1981-01-01

    The characteristics of soil formation processes in the Peat-Bog soils of waterlogged spruce phytocenoses on the Kola Peninsula are investigated. It is found that the ash composition of the peat layer is determined primarily by the composition of the buried plant residues. The effect of the chemical composition of water feeding the peat bogs is determined. (Refs. 7).

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

    EPA Science Inventory

    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...

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

    NASA Astrophysics Data System (ADS)

    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

  5. Owner survey of tarsocrural effusion (bog spavin) in Clydesdale horses.

    PubMed

    Weaver, M P; Wilant, L

    2012-03-01

    A postal survey of the owners of Clydesdale horses in the UK and USA was conducted to obtain information on tarsocrural effusion ('bog spavin') as an indicator of osteochondrosis from 935 horses. Additional information requested included details of how this condition was investigated and treated. The reported tarsocrural effusion incidence was 10 per cent. The majority of respondents believed the condition to be of concern to Clydesdale owners, but only a minority were aware of the implications of tarsocrural effusion, suggesting that owner education would be of benefit.

  6. [Testate amoebae inhabiting middle taiga bogs in Western Siberia].

    PubMed

    Kur'ina, I V; Preĭs, Iu I; Bobrov, A A

    2010-01-01

    The population of testate amoebae from the most typical middle taiga bogs of Western Siberia have been studied. More than one hundred (103) species and intraspecific taxons of testate amoebae have been revealed in recent surface samples. The relation between ecological characteristics of habitats and the composition of a Protozoa population has been demonstrated. The ecological preferences of species concerning the index of wetness, ash level, and acidity have been revealed. Using the correspondence analysis, the ecological optimums and the tolerance of species and intraspecific taxons of testate amoebae have been established.

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

    NASA Astrophysics Data System (ADS)

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

    2010-08-01

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

  8. [Carbon accumulation in soils of forest and bog ecosystems of southern Valdai in the Holocene].

    PubMed

    Minaeva, T Iu; Trofimov, S Ia; Chichagova, O A; Dorofeeva, E I; Sirin, A A; Glushkov, I V; Mikhaĭlov, I D; Kromer, B

    2008-01-01

    Carbon stocks and accumulation rates in humus and peat horizons of the contiguous soil series of forest and bog ecosystems have been studied in the Central Forest State Biosphere Reserve (CFSBR, Tver region). Upland soil types (soddy podzolic, brown, and white podzolic) have been compared to waterlogged (peaty gley podzolic and peaty gley) and bog soils differing in trophic status, including those of raised, transitional, and lowland bogs. The results show that carbon stocks in mineral soils are many times smaller than in waterlogged soils and an order of magnitude smaller than in bog soils. Mineral and bog soils are characterized by similar rates of carbon accumulation averaged over the entire period of their existence. The highest rate of carbon accumulation has been noted for the soils of waterlogged habitats, although this process may be periodically disturbed by fires and other stress influences.

  9. Uranium deposits in Grant County, New Mexico

    USGS Publications Warehouse

    Granger, Harry C.; Bauer, Herman L.; Lovering, Tom G.; Gillerman, Elliot

    1952-01-01

    The known uranium deposits of Grant county, N. Mex., are principally in the White Signal and Black Hawk districts. Both districts are within a northwesterly-trending belt of pre-Cambrian rocks, composed chiefly of granite with included gneisses, schists, and quartzites. Younger dikes and stocks intrude the pre-Cambrian complex. The White Signal district is on the southeast flanks of the Burro Mountains; the Black Hawk district is about 18 miles northwest of the town of White Signal. In the White Signal district the seconday uranium phosphates--autunite and torbernite--occur as fracture coatings and disseminations in oxidized parts of quartz-pyrite veins, and in the adjacent mafic dikes and granites; uraniferous limonite is common locally. Most of the known uraniferous deposits are less that 50 feet in their greatest dimension. The most promising deposits in the district are on the Merry Widow and Blue Jay claims. The richest sample taken from the Merry Widow mine contained more than 2 percent uranium and a sample from the Blue Jay property contained as much as 0.11 percent; samples from the other properties were of lower grade. In the Black Hawk district pitchblende is associated with nickel, silver, and cobalt minerals in fissure veins. The most promising properties in the Black Hawk district are the Black Hawk, Alhambra, and Rose mines. No uranium analyses from this district were available in 1951. There are no known minable reserves of uranium ore in either district, although there is some vein material at the Merry Widow mine of ore grade, if a market were available in the region.

  10. Radioactive deposits of Nevada

    USGS Publications Warehouse

    Lovering, T.G.

    1954-01-01

    Thirty-five occurrences of radioactive rocks had been reported from Nevada prior to 1952. Twenty-five of these had been investigated by personnel of the U. S. Geological Surveyor of the U. S. Atomic Energy Commission. Of those investigated, uranium minerals were identified at 13 sites; two sites contained a thorium mineral (monazite); the source of radioactivity on nine properties was not ascertained, and one showed no abnormal radioactivity. Of the other reported occurrences, one is said to contain uraniferous hydrocarbons and nine are placers containing thorian monazite. Pitchblende occurs at two localities, the East Walker River area, and the Stalin's Present prospect, where it is sparsely disseminated in tabular bodies cutting granitic rocks. Other uranium minerals found in the state include: carnotite, tyuyamunite, autunite, torbernite, gummite, uranophane, kasolite, and an unidentified mineral which may be dumontite. Monazite is the only thorium mineral of possible economic importance that has been reported. From an economic standpoint, only four of the properties examined showed reserves of uranium ore in 1952; these are: the Green Monster mine, which shipped 5 tons of ore to Marysvale, Utah, during 1951; the Majuba Hill mine; the Stalin's Present prospect; and the West Willys claim in the Washington district. No estimate has been made of thorium reserves and no commercial deposits of thorium are known.

  11. Radioactive deposits of Nevada

    USGS Publications Warehouse

    Lovering, T.G.

    1953-01-01

    Thirty-five occurrences of radioactive rocks had been reported from Nevada prior to 1952. Twenty-five of these had been investigated by the U. S. Geological Survey and the U. S. Atomic Energy Commission. Of those investigated, uranium minerals were identified in 13; two contained a thorium mineral (monazite); the source of radioactivity on 7 properties was not ascertained; and one showed no abnormal radioactivity. Of the other reported occurrences, one is said to contain uraniferous hydrocarbons and 9 are placers containing thorian monazite. Pitchblende occurs at two localities; the East Walker River area, and the Stalin's Present prospect, where it is sparsely disseminated in tabular bodies cutting granitic rocks. Other uranium minerals found in the state include: carnotite, tyuyamunite, autunite, torbernite, gummite, uranophane, kasolite, and an unidentified mineral which may be dumontit. Monazite is the only thorium mineral of possible economic importance that has been reported. From an economic standpoint 9 only 4 of the properties examined showed reserves of uranium ore in 1952; these are: the Green Monster mine, which shipped 5 tons of ore to Marysvale, Utah, during 1951, the Majuba Hill mine, the Stalin's Present prospect, and the West Willys claim in the Washington district. Reserves of ore grade are small on all of these properties and probably cannot be developed commercially unless an ore-buying station is set up nearby. No estimate has been made of thorium reserves and no commercial deposits of thorium are known.

  12. No limits to peat bog growth? Transport and thermodynamic constraints on anaerobic organic matter decomposition

    NASA Astrophysics Data System (ADS)

    Blodau, C.; Julia, B.; Siems, M.

    2009-05-01

    In diffusion dominated systems, for which many thick peat deposits provide a model, slowness of transport and lack of free energy may pose a limit to methanogenic decomposition of organic matter and ultimately to closing the carbon cycle. To test this hypothesis we (I) conducted controlled column experiments with homogenized peat over an 18 month period, (II) investigated transport, in situ respiration pathways, rates and thermodynamic conditions in a nothern peatland, and (III) modelled depth profiles of CO2 and CH4 in the deposits. Vertical transport in the peatland was dominated by diffusion leading to the buildup of DIC and CH4 with depth (5500 µmol L 1 DIC, 500 µmol L 1 CH4). Highest DIC and CH4 production rates occurred close to the water table (decomposition constant kd ~10-3 to 10 4 a-1) and decreased to about kd = 10-7 a-1. The accumulation of metabolic end-products diminished in situ energy yields of acetoclastic methanogenesis to the threshold for microbially mediated processes (-20 to -25 kJ mol-1 CH4). The methanogenic precursor acetate also accumulated (150 µmol L 1). In line with these findings, CH4 was formed by hydrogenotrophic methanogenesis at Gibbs free energies of 35 to 40 kJ mol-1 CH4. This was indicated by an isotopic fractionation αCO2-CH4 of 1.069 to 1.079. Fermentative degradation of acetate, propionate and butyrate attained Gibbs free energies close to 0 kJ mol-1 substrate. In peat columns with homogenenous peat-sand mixtures of 50%, 15% and 5% dry weight, steady state CO2 production also decreased from about 10 to 0 nmol cm-3 d-1 and of CH4 from 1 to 0 nmol cm-3 d-1 with depth. Very similar depth profiles of concentrations and volumetric rates developed near endproduct thresholds of 600µmol CH4 and 10 mmol L-1 CO2, despite the differences in organic matter content. The modeling exercise showed that a consistent development of CH4 concentration profiles over time in the columns could only be accomplished with rates of acetoclastic

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

    PubMed

    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.

  14. Fate of silicate minerals in a peat bog

    USGS Publications Warehouse

    Bennett, Philip C.; Siegel, Donald I.; Hillier, Barbara M.; Glaser, Paul H.

    1991-01-01

    An investigation of silicate weathering in a Minnesota mire indicates that quartz and aluminosilicates rapidly dissolve in anoxic, organic-rich, neutral- pH environments. Vertical profiles of pH, dissolved silicon, and major cations were obtained at a raised bog and a spring fen and compared. Profiles of readily extractable silicon, diatom abundance, ash mineralogy, and silicate surface texture were determined from peat cores collected at each site.In the bog, normally a recharge mound, dissolved silicon increases with depth as pH increases, exceeding the background silicon concentration by a factor of two. Silicate grain surfaces, including quartz, are chemically etched at this location, despite being in contact with pore water at neutral pH with dissolved silicon well above the equilibrium solubility of quartz. The increasing silica concentrations at circum-neutral pH are consistent with a system where silicate solubility is influenced by silica-organic-acid complexes. Silica-organic-acid complexes therefore may be the cause of the almost complete absence of diatoms in decomposed peat and contribute to the formation of silica-depleted underclays commonly found beneath coal.

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

    NASA Astrophysics Data System (ADS)

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

    2015-12-01

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

  16. Species Identification of Archaeological Skin Objects from Danish Bogs: Comparison between Mass Spectrometry-Based Peptide Sequencing and Microscopy-Based Methods

    PubMed Central

    Brandt, Luise Ørsted; Schmidt, Anne Lisbeth; Mannering, Ulla; Sarret, Mathilde; Kelstrup, Christian D.; Olsen, Jesper V.; Cappellini, Enrico

    2014-01-01

    Denmark has an extraordinarily large and well-preserved collection of archaeological skin garments found in peat bogs, dated to approximately 920 BC – AD 775. These objects provide not only the possibility to study prehistoric skin costume and technologies, but also to investigate the animal 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 MS-based methods, mostly relying on peptide fingerprinting, the shotgun sequencing approach we describe aims to identify the complete extracted ancient proteome, without preselected specific targets. As an example, we report the identification, in one of the samples, of two peptides uniquely assigned to bovine foetal haemoglobin, indicating the production of skin from a calf slaughtered within the first months of its life. We conclude that MS-based peptide sequencing is a reliable method for species identification of samples from bogs. The mass spectrometry proteomics data were deposited in the ProteomeXchange Consortium with the dataset identifier PXD001029. PMID:25260035

  17. Species identification of archaeological skin objects from Danish bogs: comparison between mass spectrometry-based peptide sequencing and microscopy-based methods.

    PubMed

    Brandt, Luise Ørsted; Schmidt, Anne Lisbeth; Mannering, Ulla; Sarret, Mathilde; Kelstrup, Christian D; Olsen, Jesper V; Cappellini, Enrico

    2014-01-01

    Denmark has an extraordinarily large and well-preserved collection of archaeological skin garments found in peat bogs, dated to approximately 920 BC - AD 775. These objects provide not only the possibility to study prehistoric skin costume and technologies, but also to investigate the animal 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 MS-based methods, mostly relying on peptide fingerprinting, the shotgun sequencing approach we describe aims to identify the complete extracted ancient proteome, without preselected specific targets. As an example, we report the identification, in one of the samples, of two peptides uniquely assigned to bovine foetal haemoglobin, indicating the production of skin from a calf slaughtered within the first months of its life. We conclude that MS-based peptide sequencing is a reliable method for species identification of samples from bogs. The mass spectrometry proteomics data were deposited in the ProteomeXchange Consortium with the dataset identifier PXD001029.

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

    PubMed

    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.

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

    NASA Astrophysics Data System (ADS)

    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

  20. Belowground carbon turnover in a temperate ombrotrophic bog

    NASA Astrophysics Data System (ADS)

    Blodau, Christian; Roulet, Nigel T.; Heitmann, Tobias; Stewart, Heather; Beer, Julia; Lafleur, Peter; Moore, Tim R.

    2007-03-01

    To examine belowground carbon (C) turnover in peatlands, we measured fluxes of carbon dioxide (CO2) and methane (CH4) by chamber measurements, estimated respiration by in situ incubations of peat, and in situ production of dissolved carbon (CO2; CH4; and dissolved organic carbon, DOC) by pore water modeling at an ombrotrophic temperate bog. Ecosystem respiration (ER) averaged 205 mmol m-2 d-1 in summer and was related to temperature, but not water table position, and in situ rates of heterotrophic respiration in the unsaturated zone were also temperature-dependent, with Q10 = 5.0 - 6.4. In the saturated zone, concentrations of 0.1 - 2.5 mmol L-1 (CO2), 0 to 0.6 mmol L-1 (CH4), and <10 - 120 mg L-1 (DOC) were recorded. Turnover was dominated by DOC unrelated to respiration, which ranged from <0.5 to 7 mmol m-2 d-1 and amounted on average to < 1% of ER. Peat decomposition constants kd were 0.060 yr-1 to 0.034 yr-1 in the unsaturated and <0.002 yr-1 in the saturated zone. Monthly averages of CH4 fluxes ranged from 0 to 1.6 mmol m-2 d-1 and were higher than modeled diffusive fluxes when threshold concentrations for CH4 ebullition were recorded closer to the peatland surface. Our results suggest that the saturated zone is of little relevance to ER in this dry temperate bog and that mobilization of DOC is a potentially more relevant process. Temperature is a more important control on ER than water table position because most of the ER is generated close to the peatland surface. Concurrent, moderate increases in temperature and soil moisture are thus likely to increase losses of CO2 from ER and of CH4 from this type of peatland.

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

    NASA Astrophysics Data System (ADS)

    Gallego-Sala, A. V.; Charman, D. J.; Harrison, S. P.; Li, G.; Prentice, I. C.

    2016-01-01

    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 that 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 expansion of

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

    NASA Astrophysics Data System (ADS)

    Gallego-Sala, A. V.; Charman, D. J.; Harrison, S. P.; Li, G.; Prentice, I. C.

    2015-10-01

    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 expansion of blanket

  3. Measurements of methane and carbon dioxide fluxes on the Bakchar bog in warm season

    NASA Astrophysics Data System (ADS)

    Krasnov, Oleg A.; Maksyutov, Shamil S.; Davydov, Denis K.; Fofonov, Aleksander V.; Glagolev, Mikhail V.

    2015-11-01

    Data terrain-atmosphere fluxes of methane and carbon dioxide overseen for measurement campaign Plotnikovo-2014 on the bog's Flux-NIES automatic complex (N56°51.29' E82° 50.91') in the warn season. Six vegetative groups on the bog's surface were taken in comparison. Improvement precise method used to determinate the sensitivity for the gases analyzers and calculating of the CO2 and CH4 fluxes measured by automated chamber-based technique.

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

    PubMed

    Heijmans, Monique M P D; van der Knaap, Yasmijn A M; Holmgren, Milena; Limpens, Juul

    2013-07-01

    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 suggests that an episode of rapid environmental change is more likely to trigger transitions to alternative ecosystem states than a gradual, but equally large, change in conditions. We used a dynamic vegetation model to explore the impacts of drought events and increased temperature on vegetation composition of temperate peat bogs. We analyzed the consequences of six patterns of summer drought events combined with five temperature scenarios to test whether an open peat bog dominated by moss (Sphagnum) could shift to a tree-dominated state. Unexpectedly, neither a gradual decrease in the amount of summer precipitation nor the occurrence of a number of extremely dry summers in a row could shift the moss-dominated peat bog permanently into a tree-dominated peat bog. The increase in tree biomass during drought events was unable to trigger positive feedbacks that keep the ecosystem in a tree-dominated state after a return to previous 'normal' rainfall conditions. In contrast, temperature increases from 1 °C onward already shifted peat bogs into tree-dominated ecosystems. In our simulations, drought events facilitated tree establishment, but temperature determined how much tree biomass could develop. Our results suggest that under current climatic conditions, peat bog vegetation is rather resilient to drought events, but very sensitive to temperature increases, indicating that future warming is likely to trigger persistent vegetation shifts.

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

    PubMed

    Novak, Martin; Pacherova, Petra

    2008-05-15

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

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

    PubMed

    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.

  7. Responses of Bog Vegetation and CO2 Exchange to Experimental N and PK Addition

    NASA Astrophysics Data System (ADS)

    Juutinen, S.; Bubier, J. L.; Shrestha, P.; Smith, R.; Moore, T.

    2008-12-01

    Atmospheric nitrogen (N) deposition has the potential to alter the structure and functioning of nutrient poor wetland ecosystems. It is important to quantify the effect of N input on ecosystem carbon (C) sequestration in these globally important C storages. We address this issue at the temperate Mer Bleue bog, ON, Canada. After 6 years of experimental fertilization, we saw that high N deposition can change mixed Sphagnum and dwarf shrub dominated communities to taller and denser dwarf shrub communities that are losing moss cover, and which might have even lower net C uptake. Now, after 8 years of fertilization and with new treatments we quantify the relationship between the plant community structure and ecosystem CO2 exchange. Three levels of N fertilization were applied with or without phosphorus and potassium (PK) into triplicate plots. We measured light saturated net ecosystem CO2 exchange (NEE), and its components ecosystem respiration and gross photosynthesis using clear and dark chambers (May-August). Vegetation characteristics were quantified by measuring foliage cover (LAI), amount of woody and foliar biomass, and abundance of moss species (point interception technique), moss growth (cranked wires) and green area of vascular leaves and moss. Addition of PK fertilizer did not alter NEE or its components relative to the control. The 8-year low N addition alone and with PK, and the 4-year fertilization with high N levels resulted in the highest net ecosystem CO2 uptake relative to the control. The ecosystem respiration increased with increasing N input rate. All levels of N fertilization resulted in higher gross photosynthesis than the control, but there was no increasing trend with increasing N input. Vascular foliage increased, while moss cover drastically decreased with increasing levels of N fertilization. At the highest level of N (and PK) addition woody biomass increased at the expense of leaf increment. Dependencies of ecosystem CO2 exchange on the

  8. The Auchenorrhyncha fauna of peat bogs in the Austrian part of the Bohemian Forest (Insecta, Hemiptera)

    PubMed Central

    Holzinger, Werner E.; Schlosser, Lydia

    2013-01-01

    Abstract The first overview on the Auchenorrhyncha fauna of peat bogs of the Austrian Bohemian Forest is presented. Seven oligotrophic peat bog sites were studied in 2011 by suction sampler (“G-Vac”) and 93 Auchenorrhyncha species (with 7465 adult specimens) were recorded. Eleven species (about 18 % of the individuals) are tyrphobiontic or tyrphophilous. The relative species abundance plot is not very steep; the six most abundant species represent 50 % of the individuals. The most common species is Conomelus anceps (17 % of the individuals). Compared to the whole Austrian Auchenorrhyncha fauna, the fauna of peat bogs comprises distinctly more univoltine species and more species hibernating in nymphal stage. Densities of adult Auchenorrhyncha in peat bogs are low in spring (about 10–60 individuals per m²) and high in July, with up to 180 (±50) individuals per m². Disturbed peat bogs have higher species numbers and higher Auchenorrhyncha densities in total, but lower numbers and densities in peat bog specialists. PMID:24039517

  9. Spatial distribution and seasonal changes of mayflies (Insecta, Ephemeroptera) in a Western Balkan peat bog.

    PubMed

    Vilenica, Marina; Brigić, Andreja; Kerovec, Mladen; Gottstein, Sanja; Ternjej, Ivančica

    2016-01-01

    Peat bogs are unique wetland ecosystems of high conservation value all over the world, yet data on the macroinvertebrates (including mayfly assemblages) in these habitats are still scarce. Over the course of one growing season, mayfly assemblages were sampled each month, along with other macroinvertebrates, in the largest and oldest Croatian peat bog and an adjacent stream. In total, ten mayfly species were recorded: two species in low abundance in the peat bog, and nine species in significantly higher abundance in the stream. Low species richness and abundance in the peat bog were most likely related to the harsh environmental conditions and mayfly habitat preferences. In comparison, due to the more favourable habitat conditions, higher species richness and abundance were observed in the nearby stream. Three of the recorded species, Caenis luctuosa from the peat bog, and Eurylophella karelica and Leptophlebia marginata from the stream are new records for the Croatian mayfly fauna. Typical Central European life cycle patterns were confirmed for several species (e.g. Baetis vernus, Nigrobaetis niger, Electrogena ujhelyii), while for several others (e.g. Habrophlebia fusca, Paraleptophlebia submarginata) some discrepancies were observed. Therefore, these results provide new and valuable information on the ecology of mayflies in peat bog habitats.

  10. Spatial distribution and seasonal changes of mayflies (Insecta, Ephemeroptera) in a Western Balkan peat bog

    PubMed Central

    Vilenica, Marina; Brigić, Andreja; Kerovec, Mladen; Gottstein, Sanja; Ternjej, Ivančica

    2016-01-01

    Abstract Peat bogs are unique wetland ecosystems of high conservation value all over the world, yet data on the macroinvertebrates (including mayfly assemblages) in these habitats are still scarce. Over the course of one growing season, mayfly assemblages were sampled each month, along with other macroinvertebrates, in the largest and oldest Croatian peat bog and an adjacent stream. In total, ten mayfly species were recorded: two species in low abundance in the peat bog, and nine species in significantly higher abundance in the stream. Low species richness and abundance in the peat bog were most likely related to the harsh environmental conditions and mayfly habitat preferences. In comparison, due to the more favourable habitat conditions, higher species richness and abundance were observed in the nearby stream. Three of the recorded species, Caenis luctuosa from the peat bog, and Eurylophella karelica and Leptophlebia marginata from the stream are new records for the Croatian mayfly fauna. Typical Central European life cycle patterns were confirmed for several species (e.g. Baetis vernus, Nigrobaetis niger, Electrogena ujhelyii), while for several others (e.g. Habrophlebia fusca, Paraleptophlebia submarginata) some discrepancies were observed. Therefore, these results provide new and valuable information on the ecology of mayflies in peat bog habitats. PMID:28138280

  11. Statistical study of geochemistry and mineralogy of uraniferous lake beds in Oligocene Brule Formation in northwestern Nebraska

    SciTech Connect

    Dickinson, K.A. )

    1989-09-01

    A small area of uranium enrichment is present in an evaporitic lake deposit of the Oligocene Brule Formation about 16 mi northeast of Chadron in northwestern Nebraska. Detrital sediments in the lake beds consist of quartz, feldspar, montmorillonite, illite, and volcanic shards. Minerals precipitated from lake waters are calcite, dolomite, and gypsum; they represent increasing concentration, in that order, of dissolved solids in lake waters. Diagenetic minerals are mainly opal and chalcedony and some calcite, dolomite, and gypsum. Elements mainly associated with detrital sediments include Al, Fe, K, Ti, Na, Li, and Cu. Elements mainly associated with chemical precipitates and diagenetic minerals are Ca, Sr, Si, Mn, and U. Silica and uranium were probably derived from volcanic ash abundant in the sediments. Uranium was deposited in the most evaporitic lake phases. No zeolites or authigenic clay minerals were found in any lake facies. Altered ash beds within the Brule contain abundant authigenic montmorillonitic clay that was apparently reworked before or during lacustrine deposition. Strontium is associated with gypsum and was apparently deposited in that mineral as a substitute for Ca. Uranium is associated with strontium, but probably only because they were both deposited during the most evaporitic periods of lake deposition. Uranium was not linked to any other element in a factor analysis (for four factors), which accounted for only about 27% of the variation in uranium.

  12. Enhanced N Deposition and Peatland Carbon Stocks in Boreal Alberta

    NASA Astrophysics Data System (ADS)

    Turetsky, M. R.; Halsey, L. A.; Vitt, D. H.; Wieder, R. K.

    2003-12-01

    Increased deposition of reactive nitrogen due to anthropogenic activities may stimulate plant growth and soil C turnover in N-limited ecosystems. Many peatland ecosystems are particularly sensitive to nitrogen deposition due their ombrotrophic nature. Here, we capitalize on a regional gradient of N deposition associated with several decades of oil sands mining. At six peatlands varying in atmospheric N loading (modeled from 1.45-3.26 kg N ha-1 yr-1), we measured Sphagnum fuscum net primary productivity (NPP). NPP rates were higher at Steepbank Bog (mean of 600 g m-2 yr-1) than at the five sites with lower N deposition (pooled mean of 182 g m-2 yr-1). At the site with the highest (Steepbank Bog) and lowest (Bleak Lake Bog) N loading, we quantified rates of C storage by 210Pb dating. Over the past 30 years of mining activity, rates of vertical peat accumulation were higher at Steepbank Bog (19.4 +/-0.4 cm) than at Bleak Lake Bog (13.9 +/-2.0 cm). However, there were no differences between sites in cumulative C storage over this 30-yr period (Steepbank: 5.0 +/-0.2 kg C m-2, Bleak Lake: 5.0 +/-0.4 kg C m-2). Together, these data suggest that increased N availability stimulates plant growth rates, leading to greater vertical accumulation of peat. However, enhanced N deposition does not appear to influence C storage in these sites, possibly due to lower peat bulk density and/or greater microbial activity.

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

    NASA Astrophysics Data System (ADS)

    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. Expanding Sloping bog Systems Under a Continental Climate in South-Central Alaska: Possible Causes and Carbon-Cycle Implications

    NASA Astrophysics Data System (ADS)

    Loisel, J.; Yu, Z.; Jones, M. C.; Booth, R. K.

    2008-12-01

    Boreal peatlands play a key role in the global carbon (C) cycle, as they have accumulated up to about a third of the global soil carbon during the Holocene. Whilst numerous peat-based paleoecological records have been published on boreal Canadian and Siberian peatlands, there are few detailed C accumulation history studies on Alaskan peatlands. Here we report our field observations and preliminary data along several transects from a sloping (blanket) bog complex in the Susitna Valley of south-central Alaska and discuss possible causes for their occurrence in this continental setting and for their recent expansion. We observed, in the field and from satellite images, the presence of extensive peatland complexes in the Susitna River watershed, including both minerotrophic and ombrotrophic peatlands. Six peat cores were collected from a vast (> 1 km2) sloping bog complex (with pH from 3.92 to 4.46), located at ~ 450 m altitude and ~ 120 km NW of Talkeetna. These cores show a clayey, thick (15-30 cm thick) tephra layer at ~ 60 cm below the peatland surface that is attributable to the Hayes volcano eruptions at 4.4-3.6 cal ka. Preliminary macrofossil analyses along these cores indicate a transition from eutrophic conditions before the tephra, to mesotrophic/oligotrophic conditions after the tephra. We suggest that the tephra layer may have modified hydrology and chemistry of the site and facilitated the development of a nutrient-poor system. Active paludification (i.e., lateral expansion) was also observed at the margins of these peatland complexes, suggesting ideal hydroclimatic conditions for peat accumulation at the present. Given that the modern climatic envelope of peatland distribution indicates that ombrotrophic mires (e.g., raised and blanket bogs) usually occur under higher mean annual precipitation than what is measured in the study region, we suggest that the hydroclimatic regime of these peatlands is determined by a complex interaction among local substrate

  15. The hydrology of natural and artificial bog pools

    NASA Astrophysics Data System (ADS)

    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

  16. Relationship between peat geochemistry and depositional environments, Cranberry Island, Maine

    USGS Publications Warehouse

    Raymond, R.; Cameron, C.C.; Cohen, A.D.

    1987-01-01

    The Heath, Great Cranberry Island, Maine, offers a unique locality for studying lateral and vertical relationships between radically different peat types within 1 km2. The majority of The Heath is a Sphagnum moss-dominated raised bog. Surrounding the raised bog is a swamp/marsh complex containing grass, sedge, Sphagnum moss, alder, tamarack, and skunk cabbage. Swamp/ marsh-deposited peat occurs both around the margins of The Heath and under Sphagnum-dominated peat, which was deposited within the raised bog. A third peat type, dominated by herbaceous aquatics, is present underlying the swamp/marsh-dominated peat but is not present as a dominant botanical community of The Heath. The three peat types have major differences in petrographic characteristics, ash contents, and associated minerals. Sulfur contents range from a low of 0.19 wt.% (dry) within the raised bog to a high of 4.44 wt% (dry) near the west end of The Heath, where swamp/marsh peat occurring directly behind a storm beach berm has been influenced by marine waters. The presence of major geochemical variations within a 1-km2 peat deposit suggests the need for in-depth characterization of potential peat resources prior to use. ?? 1987.

  17. Identifying the sources and timing of ancient and medieval atmospheric lead pollution in England using a peat profile from Lindow bog, Manchester.

    PubMed

    Le Roux, Gaël; Weiss, Dominik; Grattan, John; Givelet, Nicolas; Krachler, Michael; Cheburkin, Andriy; Rausch, Nicole; Kober, Bernd; Shotyk, William

    2004-05-01

    A peat core from Lindow bog near Manchester, England, was precisely cut into 2 cm slices to provide a high-resolution reconstruction of atmospheric Pb deposition. Radiocarbon and (210)Pb age dates show that the peat core represents the period ca. 2000 BC to AD 1800. Eleven radiocarbon age dates of bulk peat samples reveal a linear age-depth relationship with an average temporal resolution of 18.5 years per cm, or 37 years per sample. Using the Pb/Ti ratio to calculate the rates of anthropogenic, atmospheric Pb deposition, the profile reveals Pb contamination first appearing in peat samples dating from ca. 900 BC which clearly pre-date Roman mining activities. Using TIMS, MC-ICP-MS, and SF-ICP-MS to measure the isotopic composition of Pb, the (208)Pb/(206)Pb and (206)Pb/(207)Pb data indicate that English ores were the predominant sources during the pre-Roman, Roman, and Medieval Periods. The study shows that detailed studies of peat profiles from ombrotrophic bogs, using appropriate preparatory and analytical methods, can provide new insight into the timing, intensity, and predominant sources of atmospheric Pb contamination, even in samples dating from ancient times.

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

    PubMed

    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.

  19. Bog Manganese Ore: A Resource for High Manganese Steel Making

    NASA Astrophysics Data System (ADS)

    Pani, Swatirupa; Singh, Saroj K.; Mohapatra, Birendra K.

    2016-06-01

    Bog manganese ore, associated with the banded iron formation of the Iron Ore Group (IOG), occurs in large volume in northern Odisha, India. The ore is powdery, fine-grained and soft in nature with varying specific gravity (2.8-3.9 g/cm3) and high thermo-gravimetric loss, It consists of manganese (δ-MnO2, manganite, cryptomelane/romanechite with minor pyrolusite) and iron (goethite/limonite and hematite) minerals with sub-ordinate kaolinite and quartz. It shows oolitic/pisolitic to globular morphology nucleating small detritus of quartz, pyrolusite/romanechite and hematite. The ore contains around 23% Mn and 28% Fe with around 7% of combined alumina and silica. Such Mn ore has not found any use because of its sub-grade nature and high iron content, and is hence considered as waste. The ore does not respond to any physical beneficiation techniques because of the combined state of the manganese and iron phases. Attempts have been made to recover manganese and iron value from such ore through smelting. A sample along with an appropriate charge mix when processed through a plasma reactor, produced high-manganese steel alloy having 25% Mn within a very short time (<10 min). Minor Mn content from the slag was recovered through acid leaching. The aim of this study has been to recover a value-added product from the waste.

  20. Hydrologic conditions in the Klatt Bog area, Anchorage, Alaska

    USGS Publications Warehouse

    Glass, R.L.

    1986-01-01

    Klatt Bog is a 2.3 sq mi wetland in Anchorage, Alaska which provides habitat for many wildlife species but also offers potential sites for residential, commercial, and agricultural developments. Precipitation, the main source of water for the area, averages 15 in/yr; during the 1983 study period, precipitation was 12.16 inches. Estimates of evapotranspiration, considered to be the major component of water outflow, range from 10 to 20 inches. Surface runoff and groundwater outflow during 1983 are estimated to be 2.8 and < 0.2 inches, respectively. During summer, most of the runoff is derived from groundwater discharge near the upgradient eastern edge of the wetland. The wetland 's aquifer system is composed of fibrous peat which overlies a poorly permeable layer of silt and clay. The aquifer is recharged by infiltration of precipitation and inflow of groundwater from upland areas east of the wetland. During 1983 the water table was at or within 3 ft of land surface in most areas and its seasonal fluctuation was < 2 feet. Water collected from four shallow observation wells, two ponds, and two sites on a stream had concentrations of dissolved iron ranging from 2,300 to 6,100 micrograms/L. (Author 's abstract)

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

    PubMed

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

    2015-11-04

    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.

  2. Processes in the pore waters of peat deposits

    SciTech Connect

    Levshenko, T.V.; Efremova, A.G.; Galkina, Z.M.; Surkova, T.E.; Tolstov, K.A.

    1983-01-01

    The composition of the waters of modern peat bogs that have developed in the intracontinental regions under the conditions of bogs of the high-moor, mixed, and lowmoor types have been investigated for the case of a number of peat deposits of the Smolensk, Volgorad, and Pskov provinces. During the work the pH of the deposits and the C1-, Alk, SO/sup 2/-, Ca/sup 2 +/, Mg/sup 2 +/, K- contents of the pore water of modern peat beds were studied. The thickness of the deposits studied amounted to 5-7 m. Samples were taken every 0.5 m in depth. The water was separated from the deposits by pressing out.

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

    NASA Astrophysics Data System (ADS)

    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

  4. A new peat bog testate amoeba transfer function and quantitative palaeohydrological reconstructions from southern Patagonia

    NASA Astrophysics Data System (ADS)

    van Bellen, S.; Mauquoy, D.; Payne, R.; Roland, T. P.; Hughes, P. D.; Daley, T. J.; Street-Perrot, F. A.; Loader, N.

    2013-12-01

    Testate amoebae have been used extensively as proxies for environmental change and palaeoclimate reconstructions in European and North American peatlands. The presence of these micro-organisms in surface samples is generally significantly linked to the local water table depth (WTD) and preservation of the amoeba shells downcore allows for millennial length water table reconstructions. Peat bog archive records in southern Patagonia are increasingly the focus of palaeoecological research due to the possibility of detecting changes in the Southern Westerlies. These Sphagnum magellanicum-dominated peat bogs are characterised by a wide range of water table depths, from wet hollows to high hummocks (>100 cm above the water table). Here we present the first transfer function for this region along with ~2k-year palaeorecords from local peat bogs. A modern dataset (155 samples) was sampled along transects from five bogs in 2012 and 2013. Measurements of WTD, pH and conductivity were taken for all samples. The transfer function model was based on the 2012 dataset, while the 2013 samples served as an independent test set to validate the model. Besides the standard leave-one-out cross-validation, we applied leave-one-site-out and leave-one transect-out cross-validation, which are effective means of verifying the degree of clustering in the dataset. To ensure that the environmental gradient had been evenly sampled we quantified the root-mean-squared error of prediction (RMSEP) individually for segments of this gradient. Ordinations showed a clear hydrological gradient in amoeba assemblages, with the dominant Assulina muscorum at the dry end and Amphitrema wrightianum and Difflugia globulosa at the wet end. Canonical correspondence analysis showed that WTD was the most important environmental variable, accounting for 18% of the variance in amoeba assemblages. A weighted averaging-partial least squares model showed best performance in cross-validation, using the 2013 data as an

  5. Transient modelling of water-table variation in a floodplain wetland, Narborough Bog, Leicestershire

    NASA Astrophysics Data System (ADS)

    Bradley, C.

    1996-11-01

    This paper describes the application of a transient three-dimensional groundwater model to simulate water flux through a floodplain wetland, Narborough Bog, in Central England. The results of a programme of water-table monitoring are summarised to indicate the extent of water-table fluctuation, and experiments to determine hydraulic flow parameters are detailed. Hydraulic conductivities of deposits are highly variable; observations were in the range 1.16 × 10 -3-4.63 × 10 -2 cm s -1 for herbaceous peat, 1.16 10 -4 cm s -1 for wood peat, and 9.14 × 10 -6-3.36 × 10 -8 cm s -1 for silty clay. A three-layer groundwater model of the wetland is developed using MODFLOW from these initial values, and with stratigraphic data obtained by hand augering. The model is calibrated using data for two periods of recharge from precipitation by adjusting specific yield and vertical hydraulic conductivity within prescribed limits. The accuracy of the model is then assessed by comparing daily model predictions of water-table response to potential evapotranspiration at specific monitoring points. Model, results demonstrate the importance of variation in hydraulic characteristics with depth in wetlands, thus emphasizing the dependence of water-table response upon water-table position, and preceding moisture conditions. The resulting water-table configuration reflects the balance between horizontal and lateral water flow through the wetland, and its relationship to river stage. The success of the stratigraphic representation is considered and its general applicability evaluated. Finally, the use of the calibrated model for local hydrological management is considered, and the effects on the wetland water budget of varying river stage by specified amounts are examined.

  6. Content and binding forms of heavy metals, aluminium and phosphorus in bog iron ores from Poland.

    PubMed

    Kaczorek, Danuta; Brümmer, Gerhard W; Sommer, Michael

    2009-01-01

    Bog iron ores are widespread in Polish wetland soils used as meadows or pastures. They are suspected to contain high concentrations of heavy metals, which are precipitated together with Fe along a redox gradient. Therefore, soils with bog iron ore might be important sources for a heavy metal transfer from meadow plants into the food chain. However, this transfer depends on the different binding forms of heavy metals. The binding forms were quantified by sequential extraction analysis of heavy metals (Fe, Mn, Cr, Co, Ni, Cd, Pb) as well as Al and P on 13 representative samples of bog iron ores from central and southwestern Poland. Our results showed total contents of Cr, Co, Ni, Zn, Cd, and Pb not to exceed the natural values for sandy soils from Poland. Only the total Mn was slightly higher. The highest contents of all heavy metals have been obtained in iron oxide fractions V (occluded in noncrystalline and poorly crystalline Fe oxides) and VI (occluded in crystalline Fe oxides). The results show a distinct relationship between the content of Fe and the quantity of Zn and Pb as well P. Water soluble as well as plant available fractions were below the detection limit in most cases. From this we concluded bog iron ores not to be an actual, important source of heavy metals in the food chain. However, a remobilization of heavy metals might occur due to any reduction of iron oxides in bog iron ores, for example, by rising groundwater levels.

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

    PubMed

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

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

  8. Environmental monitoring in peat bog areas by change detection methods

    NASA Astrophysics Data System (ADS)

    Michel, Ulrich; Mildes, Wiebke

    2016-10-01

    Remote sensing image analysis systems and geographic information systems (GIS) show great promise for the integration of a wide variety of spatial information supporting tasks such as urban and regional planning, natural resource management, agricultural studies and topographic or thematic mapping. Current and future remote sensing programs are based on a variety of sensors that will provide timely and repetitive multisensor earth observation on a global scale. GIS offer efficient tools for handling, manipulating, analyzing and presenting spatial data that are required for sensible decision making in various areas. The Environmental Monitoring project may serve as a convincing example of the operational use of integrated GIS/remote sensing technologies. The overall goal of the project is to assess the capabilities of satellite remote sensing for the analysis of land use changes, especially in moor areas. These areas are recognized as areas crucial to the mission of the Department of Environment and, therefore, to be placed under an extended level of protection. It is of critical importance, however, to have accurate and current information about the ecological and economic state of these sensitive areas. In selected pasture and moor areas, methods for multisensor data fusion have being developed and tested. The results of this testing show which techniques are useful for pasture and moor monitoring at an operational level. A hierarchical method is used for extracting bog land classes with respect to the environmental protection goals. A highly accurate classification of the following classes was accomplished: deciduous- and mixed forest, coniferous forest, water, very wet areas, meadowland/farmland with vegetation, meadowland/farmland with partly vegetation, meadowland/ farmland without vegetation, peat quarrying with maximum of 50% vegetation, de- and regeneration stages. In addition, a change detection analysis is performed in comparison with the existing

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

    PubMed

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

    2014-09-01

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

  10. 77 FR 2970 - Notice of Intent To Prepare an Environmental Assessment for the Proposed Elba BOG Compressor...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-20

    ... Elba BOG Compressor Project and Request for Comments on Environmental Issues; Southern LNG Company, L.L... involving construction and operation of facilities by Southern LNG Company, L.L.C. (SLNG) in Chatham County... (BOG) compression facilities at its liquefied natural gas (LNG) marine terminal on Elba Island...

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

    PubMed Central

    Park, Jincheol; Taslim, Cenny; Lin, Shili

    2015-01-01

    BOG (Bacterium and virus analysis of Orthologous Groups) is a package for identifying groups of differentially regulated genes in the light of gene functions for various virus and bacteria genomes. It is designed to identify Clusters of Orthologous Groups (COGs) that are enriched among genes that have gone through significant changes under different conditions. This would contribute to the detection of pathogens, an important scientific research area of relevance in uncovering bioterrorism, among others. Particular statistical analyses include hypergeometric, Mann–Whitney rank sum, and gene set enrichment. Results from the analyses are organized and presented in tabular and graphical forms for ease of understanding and dissemination of results. BOG is implemented as an R-package, which is available from CRAN or can be downloaded from http://www.stat.osu.edu/~statgen/SOFTWARE/BOG/. PMID:26106460

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

    PubMed

    Park, Jincheol; Taslim, Cenny; Lin, Shili

    2015-01-01

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

  13. Holocene Carbon Accumulation Rates in the SPRUCE Bog Prior to Warming and Elevated CO2 Treatment

    NASA Astrophysics Data System (ADS)

    McFarlane, K. J.; Iversen, C. M.; Phillips, J. R.; Brice, D. J.; Hanson, P. J.

    2015-12-01

    In the Spruce and Peatland Responses Under Climatic and Environmental Change (SPRUCE) experiment warming and elevated CO2 treatments are being applied to an ombrotrophic spruce bog: the S1 Bog (S1) at Marcell Experimental Forest in northern Minnesota. To provide a historical context for recent and expected experimentally-induced changes in the bog's belowground carbon balance, we reconstructed historical carbon accumulation rates in peat using radiocarbon from 19 peat cores collected from randomly distributed SPRUCE plots. This unusually high number of cores allows us to assess spatial variability in age-depth profiles and accumulation rates across the SPRUCE study area within S1. This data, along with recent C flux measurements, show that the bog has been accumulating carbon for at least 12,0000 years and has continued to be a sink for atmospheric carbon of approximately 150 g C m-2 yr-1 in recent decades. Early Holocene accumulation rates are similar to those reported for other northern peatlands (approximately 25 g C m-2 yr-1), but apparent carbon accumulation decreased substantially around 3,000 years ago (to 5-15 g C m-2 yr-1) and stayed low until the last century. This decrease is considerably larger than that reported for other peatlands and is therefore unlikely to result only from cooling during the Holocene or bog succession. Although no charcoal has been found in peat at this site, evidence from a neighboring bog indicates a considerable amount of peat formed during this period was consumed by fire and it is possible that smoldering fires consumed peat, resulting in low apparent accumulation rates. Past droughts may have also contributed to observed trends by lowering the acrotelm/catotelm boundary, allowing for enhanced aerobic peat decomposition. This work provides important background information on spatial variability and carbon biogeochemistry that will aid in interpretation of climate change simulation experiments at S1.

  14. The core microbiome bonds the Alpine bog vegetation to a transkingdom metacommunity.

    PubMed

    Bragina, Anastasia; Berg, Christian; Berg, Gabriele

    2015-09-01

    Bog ecosystems fulfil important functions in Earth's carbon and water turnover. While plant communities and their keystone species Sphagnum have been well studied, less is known about the microbial communities associated with them. To study our hypothesis that bog plants share an essential core of their microbiome despite their different phylogenetic origins, we analysed four plant community plots with 24 bryophytes, vascular plants and lichen species in two Alpine bogs in Austria by 16S rDNA amplicon sequencing followed by bioinformatic analyses. The overall bog microbiome was classified into 32 microbial phyla, while Proteobacteria (30.8%), Verrucomicrobia (20.3%) and Planctomycetes (15.1%) belonged to the most abundant groups. Interestingly, the archaeal phylum Euryarcheota represented 7.2% of total microbial abundance. However, a high portion of micro-organisms remained unassigned at phylum and class level, respectively. The core microbiome of the bog vegetation contained 177 operational taxonomic units (OTUs) (150 526 seq.) and contributed to 49.5% of the total microbial abundance. Only a minor portion of associated core micro-organisms was host specific for examined plant groups (5.9-11.6%). Using our new approach to analyse plant-microbial communities in an integral framework of ecosystem, vegetation and microbiome, we demonstrated that bog vegetation harboured a core microbiome that is shared between plants and lichens over the whole ecosystem and formed a transkingdom metacommunity. All micro- and macro-organisms are connected to keystone Sphagnum mosses via set of microbial species, for example Burkholderia bryophila which was found associated with a wide spectrum of host plants and is known for a beneficial plant-microbe interaction.

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

    NASA Astrophysics Data System (ADS)

    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; p<0.0001; n=21. Related to groundwater level, the N2O fluxes peak at around -40cm. Variation in greenhouse gas 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.

  16. Water table related variations in the abundance of intact archaeal membrane lipids in a Swedish peat bog.

    PubMed

    Weijers, Johan W H; Schouten, Stefan; van der Linden, Marjolein; van Geel, Bas; Damsté, Jaap S Sinninghe

    2004-10-01

    The presence and distribution of isoprenoid glycerol dialkyl glycerol tetraethers (GDGTs), lipids that constitute the membranes of Archaea, have been investigated in a 50-cm long core from a Swedish peat bog. In the acrotelm, the periodically water saturated and thus oxic upper layer of the peat bog, only minor amounts of GDGTs were found. These amounts increase considerably in the catotelm, the continuously water saturated and consequently anoxic lower layer of the peat bog. Based on earlier analyses of GDGTs in different settings and on 16S rDNA results from literature, these lipids are likely derived from methanogenic Archaea. Crenarchaeol, previously only found in marine settings and in fresh water lakes, has also been found in this peat bog. Contrary to the other GDGTs, crenarchaeol concentrations remain relatively constant throughout the peat core, suggesting that they are produced by Crenarchaeota thriving in the oxic part of the peat bog and possibly also in the anoxic part.

  17. A new anoplocephalid cestode from the southern bog lemming Synaptomys cooperi.

    PubMed

    Haukisalmi, Voitto; Eckerlin, Ralph P

    2009-06-01

    A new cestode species, Anoplocephaloides bulmeri n. sp. (Cestoda: Anoplocephalidae), is described from the southern bog lemming Synaptomys cooperi (Baird) from Virginia. The general morphology of A. bulmeri strongly suggests that it belongs to the monophyletic Anoplocephaloides Baer 1923 s. str. It differs unequivocally from the other species of Anoplocephaloides s. str. by the distribution of testes in the poral part of the proglottid and also by the number of testes and the maximum length of the cirrus sac and seminal receptacle. Anoplocephaloides bulmeri most closely resembles Anoplocephaloides kontrimavichusi Rausch, 1976, a host-specific parasite of the northern bog lemming, Synaptomys borealis (Richardson).

  18. 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.

    PubMed

    De Vleeschouwer, François; Gérard, Laëtitia; Goormaghtigh, Catherine; Mattielli, Nadine; Le Roux, Gaël; Fagel, Nathalie

    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 (14)C and (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.

  19. Peat porewaters have contrasting geochemical fingerprints for groundwater recharge and discharge due to matrix diffusion in a large, northern bog-fen complex

    NASA Astrophysics Data System (ADS)

    Levy, Zeno F.; Siegel, Donald I.; Glaser, Paul H.; Samson, Scott D.; Dasgupta, Soumitri S.

    2016-10-01

    Although northern peatlands represent a globally significant reservoir for carbon, considerable uncertainty exists concerning solute transport systems within large (>1000 km2) peat deposits. We therefore delineated geochemical gradients linked to groundwater recharge and discharge along a 6 km transect within the 1200 km2 Red Lake Peatland of northwestern Minnesota. We used ratios of Ca/Mg and 87Sr/86Sr to distinguish discharge of calcareous groundwater (∼1.4 and 0.7155, respectively) to the peatland from the mineral substratum along a topographic gradient from a bog crest downslope to an internal fen water track and bog islands. In contrast, the stable isotopes of the porewaters (δ18O from -12.8 ‰ to -7.8 ‰) show that the active pore-spaces in these peat profiles have been flushed by recharge from the near-surface peat. We hypothesize that back-diffusion of groundwater-derived solutes from the peat matrix to active pore-spaces has allowed the geochemical signal from paleo-hydrogeologic discharge to persist into the current regime of dilute recharge. This effect has not been observed previously on the landform-scale and has important implications for carbon cycling in peatlands.

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

    NASA Astrophysics Data System (ADS)

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

    2014-12-01

    Peatlands cover only 3% of the Earth's surface, yet store a third of soil carbon. Increasing global temperatures have the potential to change peatlands from a net sink to a net source of atmospheric carbon. N is a limiting nutrient in oligotrophic Sphagnum-dominated peatlands and biological N2 fixation likely supplies a significant but unknown fraction of N inputs. Moreover, environmental controls on diazotrophic community composition in N-limited peatlands are poorly constrained. Thus, improved understanding of feedbacks between the CH4 and N cycles is critical for predicting future changes to CH4 flux from peat bogs. We coupled measurements of N2 fixation activity measured by the acetylene (C2H2) reduction assay (ARA) with molecular analyses of expression and diversity of nifH genes encoding the molybdenum (Mo)-containing nitrogenase from two peat bogs in the Marcell Experimental Forest, Minnesota, USA. The top 10 cm of peat was sampled from the high CH4 flux S1 bog and the low CH4 flux Zim bog in April and June 2014. Despite similar N concentrations in the top 10 cm of both bogs (0.5-1.0 μM NO2-+NO3- and 2-3 μM NH4+), the S1 bog displayed variable ARA activity (1-100 nmol C2H4 h-1 g-1) whereas the Zim bog had consistently low ARA activity (<1 nmol C2H4 h-1 g-1). Highest ARA activity was measured in June from S1 bog hollows with higher moisture content incubated without O2 in the light (20-100 nmol C2H4 h-1 g-1). Dissolved Fe (1-25 μM) was higher in hollow vs. hummock samples, and at S1 vs. Zim bog, while dissolved V (4-14 nM) was consistently higher than Mo (1-4 nM), suggesting that alternative V or Fe-containing nitrogenases might be present in these bogs. In contrast, Cu, an essential micronutrient for aerobic methanotrophs, was higher in hummocks (25-48 nM) than hollows (6-17 nM). The facultative methanotroph Methylocella was the dominant diazotroph in the S1 bog based on high throughput next generation sequencing of nifH cDNA amplicons. Given previous

  1. Isotopic evolution of atmospheric Pb from metallurgical processing in Flin Flon, Manitoba: Retrospective analysis using peat cores from bogs.

    PubMed

    Shotyk, W; Rausch, N; Outridge, P M; Krachler, M

    2016-11-01

    Atmospheric Pb deposition was reconstructed using peat cores from bogs in the vicinity of Flin Flon, Manitoba, Canada, home to a zinc refinery and copper smelter. The Sask Lake (SL4-1) core was collected 85 km NW of Flin Flon and Kotyk Lake (KOL) 30 km NE. The distribution of Sr and U show that both profiles are predominantly minerotrophic (ie groundwater-fed), but the Pb concentration profile shows that Pb was received exclusively from the atmosphere. Graphs of (208)Pb/(206)Pb against (206)Pb/(207)Pb document atmospheric Pb contamination dating from the early to mid-1800's, well before the start of metallurgical processing (in 1930) and attributable to long-range atmospheric transport from other regions of North America. Industrial activities at Flin Flon clearly affected the concentrations, enrichment factor (calculated using Sc), and accumulation rates of Pb, but it is the similarity in isotopic composition, and contrast with crustal values ((206)Pb/(207)Pb ca. 1.20 to 1.22) which makes the connection to the Flin Flon ores. The KOL samples dating from 1925-1976 CE have a (206)Pb/(207)Pb of 1.032 ± 0.002 (n = 11) which approach the values for the Flin Flon ores ((206)Pb/(207)Pb = 1.008). But even at SL4-1, the peat samples dating from 1925-1976 CE have a (206)Pb/(207)Pb of 1.061 ± 0.022 (n = 18) which is well below the corresponding ratio of Canadian leaded gasoline ((206)Pb/(207)Pb = ca. 1.15). The SL4-1 site too, therefore, was clearly impacted by Pb from mining and metallurgy, despite the distance (88 km) from Flin Flon and being predominantly upwind. These two bogs not only provide the chronology of atmospheric Pb deposition for the past decades, but suggest that the extent of contamination may have been underestimated by previous studies.

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

    NASA Astrophysics Data System (ADS)

    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

  3. Hydrological instability of a Baltic raised bog during the last 1000 years in northern Poland

    NASA Astrophysics Data System (ADS)

    Lamentowicz, Mariusz; Galka, Mariusz; Pawlyta, Jacek; Lamentowicz, Lukasz; Goslar, Tomasz; Miotk-Szpiganowicz, Grażyna; Mitchell, Edward A. D.

    2010-05-01

    Our aim was to reconstruct the palaeohydrological of a Baltic raised bog located in northern Poland over the last 1000 years. We used several proxies: testate amoebae, plant macrofossils, pollen and carbon stable isotopes to reconstruct the bog surface wetness. We analysed two replicated monoliths collected from the same bog at high temporal resolution. We obtained a reliable chronology for both monoliths based on radiocarbon and lead 210 dating. We compared the inferred water table depth changes obtained from the quantitative reconstruction based on the testate amoebae transfer function with inference from plant remains and carbon isotopic composition of Sphagnum stems for both monoliths. Our data provide new insight on human impact on the hydrology of Baltic raised bogs and the sensitivity of these peatlands to various disturbances. We show an increasing hydrological instability of the studied peatland concomitant with the gradually increasing human impact over the landscape since the Medieval Period. However, climatic change also played an important role during the Little Ice Age period that overlapped with the anthropogenic disturbance. This palaeoenvironmental data provides useful baseline data for peatland management and restoration in Northern Poland and more generally illustrate the value of high-resolution multiproxy studies as tool for both palaeoenvironmental studies and current management.

  4. Ecology of southeastern shrub bogs (pocosins) and Carolina bays: a community profile

    SciTech Connect

    Sharitz, R.R.; Gibbons, J.W.

    1982-11-01

    Shrub bogs of the Southeast occur in areas of poorly developed internal drainage that typically but not always have highly developed organic or peat soils. Pocosins and Carolina bays are types or subclasses of shrub bogs on the coastal plains of the Carolinas and Georgia. They share roughly the same distribution patterns, soil types, floral and faunal species composition and other community attributes, but differ in geological formation. Carolina bays may contain pocosin as well as other communities, but are defined more by their unique elliptical shape and geomorphometry. The pocosin community is largely defined by its vegetation, a combination of a dense shrub understory and a sparser canopy. The community is part of a complex successional sequence of communities (sedge bogs, savannas, cedar bogs, and bay forests) that may be controlled by such factors as fire, hydroperiod, soil type, and peat depth. Pocosins and Carolina bays harbor a number of animal groups and may be locally important in their ecology. Although few species are endemic to these habitats, they may provide important refuges for a number of species. These communities are simultaneously among the least understood and most rapidly disappearing habitats of the Southeast. Forestry and agricultural clearage are current impacts.

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

    ERIC Educational Resources Information Center

    Naik, B. M.

    2012-01-01

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

  6. Health survey of wild and captive bog turtles (Clemmys muhlenbergii) in North Carolina and Virginia.

    PubMed

    Brenner, Deena; Lewbart, Gregory; Stebbins, Martha; Herman, Dennis W

    2002-12-01

    Blood samples, fecal samples, and cloacal swabs were collected from 42 bog turtles (Clemmys muhlenbergii). including 14 wild males, 22 wild females, three captive males, and three captive females, in Virginia and North Carolina, USA. Samples were analyzed for hematologic and plasma chemistry values, Mycoplasma sp. antibodies, intestinal parasites, and normal cloacal flora.

  7. Lake or bog? Reconstructing baseline ecological conditions for the protected Galápagos Sphagnum peatbogs

    NASA Astrophysics Data System (ADS)

    Coffey, Emily E. D.; Froyd, Cynthia A.; Willis, Katherine J.

    2012-10-01

    This paper documents the first 10,000 year old plant macrofossil record of vegetation changes on the central island of Santa Cruz, providing information on Sphagnum bog vegetation patterns, local extinction of key taxa, and temporal successions in the Galápagos humid highlands. Vegetation change is reconstructed through examination of Holocene sedimentary sequences obtained from three Sphagnum bogs located within volcanic caldera forming the high elevation central ridge system of Santa Cruz Island. Results indicate that these specialized Sphagnum bog ecosystems are dynamic and have undergone considerable changes in vegetation composition, transitioning from diverse hygrophilous herbs and submerged aquatic ecosystems to drier Sphagnum/Pteridium bog systems, during the last 10,000 cal yr BP. Additionally a new aquatic genus previously undocumented on the islands, Elatine, was discovered at two of the study sites, but it is now extinct on the archipelago. Some of the observed vegetation successions may have been driven by climatic shifts occurring within the eastern equatorial Pacific (EEP). Other drivers including anthropogenic change are also considered significant over the last hundred years, placing strain on this naturally dynamic system. This study helps reveal patterns of change in the humid highlands over the last 10,000 cal yr BP regarding vegetation variability, climatic shifts, the historical influence of fire, tortoise disturbance, and recent anthropogenic impacts on the island.

  8. Spatial structure and persistence of methanogen populations in humic bog lakes.

    PubMed

    Milferstedt, Kim; Youngblut, Nicholas D; Whitaker, Rachel J

    2010-06-01

    Patterns of diversity within methanogenic archaea in humic bog lakes are quantified over time and space to determine the roles that spatial isolation and seasonal mixing play in structuring microbial populations. The protein encoding gene mcrA is used as a molecular marker for the detection of fine-scale differences between methanogens in four dimictic bog lakes in which the water column is mixed twice a year and one meromictic lake that is permanently stratified. Although similar sequences are observed in each bog lake, each lake has its own characteristic set of persisting sequence types, indicating that methanogen populations are delimited either by low migration between the anaerobic hypolimnia or by lake-specific selection. The meromictic lake is differentiated from all other lakes and contains sequences with a higher degree of microdiversity than the dimictic lakes. By relating the structure of diversity to the depth of each bog lake, we propose the hypothesis that the deeper parts of the water column favor microdiversification of methanogens, whereas the periodically disturbed water column of shallower dimictic lakes promote genetically more diverse methanogen communities.

  9. Methanogen communities and Bacteria along an ecohydrological gradient in a northern raised bog complex.

    PubMed

    Juottonen, Heli; Galand, Pierre E; Tuittila, Eeva-Stiina; Laine, Jukka; Fritze, Hannu; Yrjälä, Kim

    2005-10-01

    Mires forming an ecohydrological gradient from nutrient-rich, groundwater-fed mesotrophic and oligotrophic fens to a nutrient-poor ombrotrophic bog were studied by comparing potential methane (CH(4)) production and methanogenic microbial communities. Methane production was measured from different depths of anoxic peat and methanogen communities were detected by detailed restriction fragment length polymorphism (RFLP) analysis of clone libraries, sequencing and phylogenetic analysis. Potential CH(4) production changed along the ecohydrological gradient with the fens displaying much higher production than the ombrotrophic bog. Methanogen diversity also decreased along the gradient. The two fens had very similar diversity of methanogenic methyl-coenzyme M reductase gene (mcrA), but in the upper layer of the bog the methanogen diversity was strikingly lower, and only one type of mcrA sequence was retrieved. It was related to the Fen cluster, a group of novel methanogenic sequences found earlier in Finnish mires. Bacterial 16S rDNA sequences from the fens fell into at least nine phyla, but only four phyla were retrieved from the bog. The most common bacterial groups were Deltaproteobacteria, Verrucomicrobia and Acidobacteria.

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

    PubMed

    Wang, Shao-Yang; Li, Yi-Qing; Li, Teng; Yang, Hang-Yu; Ren, Jie; Zhang, Bo-Lin; Zhu, Bao-Qing

    2016-12-29

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

  11. Study of speciation and size fractionation of trace element between soil solution, bog, river and lake within a boreal watershed (North Karelia, NW Russia) using fractional filtration

    NASA Astrophysics Data System (ADS)

    Ilina, Svetlana M.; Lapitsky, Sergey A.; Alekhin, Yuriy V.; Pokrovsky, Oleg S.; Viers, Jerome

    2010-05-01

    This work is aimed at studying the evolution of migration forms of true dissolved compounds and colloidal entities using an integrated approach of molecular mass distribution and differences in the association of trace elements (TE) with organic matter (OM) or Fe colloids in the system soil water-bog-river-lake. Characterization of TE speciation with colloids during TE migration from the site of colloids origin (bog and soil solutions) towards the transit zone (river) and finally to the deposition, accumulation or transformation zone (lake) is a main fundamental task of this problem. The objects of study include a small stream watershed Vostochniy and the river Palayoki (North Karelia, Russia). The water samplings were performed in July and August 2008 and 2009 and included soil solution, nourishing bog, the middle part of the brook originated from the swamp, the mouth of the brook and the lake Zipringa. We sampled large volumes (50 - 100 liters), and we applied, directly in the in-field-installed "clean laboratory" the sequential frontal filtration and ultrafiltration of samples through the filters of progressively decreasing poresize 100, 20, 10, 5, 0.8, 0.4, 0.2 and 0.1 microns; 100 kDa (0.0065 micron), 10 kDa (0.003 micron) and 1 kDa (0.0014 micron). This allowed separation of organic matter, coarse and fine particulate matter and colloids. All filtrates and selected retentates were analyzed for a wide range of macro-and micronutrients using ICP-MS. In filtrates of the river water, a significant decrease of iron concentration occurred in the range of 5 micron to 0.22 micron and from 100 kDa to 1 kDa. For alkali and alkaline earth elements (Mg, K, Ca), as well as for Cu, Ni, Cr the concentrations changed after passing through the 10 kDa membrane. Na concentration remains constant in all filtrates. The filtrates of the soil solution are characterized by a significant decreases in Na, K, after 0.1 micron, Ca, Cu in the range of 0.22 micron - 100 kDa and Mg, Ni in

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

    NASA Astrophysics Data System (ADS)

    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.

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

    PubMed

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

    2013-01-01

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

  14. High potential of nitrogen fixation in pristine, ombrotrophic bogs in Southern Patagonia

    NASA Astrophysics Data System (ADS)

    Knorr, Klaus-Holger; Horn, Marcus A.; Bahamonde Aguilar, Nelson A.; Borken, Werner

    2015-04-01

    Nitrogen (N) input in pristine peatlands occurs via natural input of inorganic N through atmospheric deposition or biological dinitrogen (N2) fixation. However, N2 fixation is to date mostly attributed to bacteria and algae associated to Sphagnum and its contribution to plant productivity and peat buildup has been often underestimated in previous studies. Based on net N storage, exceptionally low N deposition, and high abundance of vascular plants at pristine peatlands in Southern Patagonia, we hypothesized that there must be a high potential of non-symbiotic N2 fixation not limited to the occurrence of Sphagnum. To this end, we chose two ombrotrophic bogs with spots that are dominated either by Sphagnum or by vascular, cushion-forming plants and sampled peat from different depths for incubation with 15N2 to determine N2 fixation potentials. Moreover, we analyzed 15N2 fixation by a nodule-forming, endemic conifer inhabiting the peatlands. Results from 15N2 uptake were compared to the conventional approach to study N2 fixation by the acetylene reduction assay (ARA). Using 15N2 as a tracer, high non-symbiotic N2 fixation rates of 0.3-1.4 μmol N g-1 d-1 were found down to 50 cm under micro-oxic conditions (2 vol.%) in samples from both plots either covered by Sphagnum magellanicum or by vascular cushion plants. Peat N concentrations suggested a higher potential of non-symbiotic N2 fixation under cushion plants, likely because of the availability of easily decomposable organic compounds as substrates and oxic conditions in the rhizosphere. In the Sphagnum plots, high N2 fixation below 10 cm depth would rather reflect a potential fixation that may switch on during periods of low water levels when oxygen penetrates deeper into the peat. 15N natural abundance of live Sphagnum from 0-10 cm pointed to N uptake solely from atmospheric deposition and non-symbiotic N2 fixation. 15N signatures of peat from the cushion plant plots indicated additional N supply from N

  15. 15-ky Peat Paleo-Monsoon Reconstructions from Lipid Biomarker Contents of Three Bogs in China

    NASA Astrophysics Data System (ADS)

    Zhou, W.; Zheng, Y.; Meyers, P. A.; Xie, S.

    2007-12-01

    Paleoclimate reconstructions based on lipid biomarkers from peat bogs are relatively uncommon, although this approach has been widely applied to lake sediments where it yields important histories of climate-related changes in types of vegetation and organic matter preservation. We describe stratigraphic patterns in peat lipid biomarker distributions extracted from three well-dated peat cores. One core is from the Dingnan bog on the border of Guangdong and Jiangxi Provinces of southeastern China. A second core is from the Zoige-Hongyuan bog, which is on the Qinghai-Xizang Plateau of west China on the northeast edge of the Tibetan Plateau. The third peat core is from a shallow lake that is the source of the Hani River in Jiling Province of northeastern China. The combination of the three locations provides a broad regional history of the evolution of monsoon-influenced climate in China from the late-glacial through the Holocene. The start of peat accumulation in these locations at about 15 ka indicates the onset of wetter post-glacial climate. A period of warmer climate corresponding to the Holocene Optimum between 9 ka to 5 ka is evident in greater alterations of n-alkanoic acids and n-alkanols and in the appearance of biomarkers diagnostic of greater microbial activity. Changes in local precipitation that raised the water level of the Zoige-Hongyuan bog are indicated by increases in the proportions of C23 and C25 n- alkanes that are mainly derived from submerged/floating plants and by conversion of the Dingnan bog to a lake. Alternations in submergent and emergent plant n-alkane proxies reveal millennial scale rises and falls of the water level in these bogs, thereby reflecting variations in East Asian and Indian Ocean monsoon precipitation during the Holocene. These events correlate well with cold-dry events recorded in same regions by other climatic proxies. Our results reflect Holocene instability in the Asian monsoon system and indicate that millennial

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

    PubMed

    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.

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

    PubMed

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

    2013-08-01

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

  18. Seasonal changes of microbial communities in two shallow peat bog lakes.

    PubMed

    Lew, Sylwia; Koblížek, Michal; Lew, Marcin; Medová, Hana; Glińska-Lewczuk, Katarzyna; Owsianny, Paweł Michał

    2015-03-01

    Peat bog lakes represent important ecosystems in temperate and boreal zones. We investigated the seasonal dynamics of the microbial community in two small peat bog lakes, Kuźnik Olsowy and Kuźnik Bagienny, located in western Poland. Fluorescence in situ hybridization analyses revealed that the bacterial community was dominated by Proteobacteria and Actinobacteria, in addition to a substantial number of archaea. An infrared epifluorescence analysis demonstrated that aerobic anoxygenic phototrophs (AAPs) constituted a significant fraction of bacterial plankton (1-19%). All the bacterial groups exhibited large seasonal changes whose course differed between the studied lakes. While chlorophyll had its maximum during winter or early summer, AAPs peaked in summer, when the growth of this group was stimulated by higher irradiance and elevated water temperatures.

  19. Investigation of gas exchange processes in peat bog ecosystems by means of innovative Raman gas spectroscopy.

    PubMed

    Frosch, Torsten; Keiner, Robert; Michalzik, Beate; Fischer, Bernhard; Popp, Jürgen

    2013-02-05

    Highly sensitive Raman gas spectroscopy is introduced for simultaneous real time analysis of O(2), CO(2), CH(4), and N(2) in order to elucidate the dynamics of greenhouse gases evolving from climate-sensitive ecosystems. The concentrations and fluxes of this suite of biogenic gases were quantified in the head space of a water-saturated, raised peat bog ecotron. The intact peat bog, exhibiting various degradation stages of peat and sphagnum moss, was exposed to various light regimes in order to determine important ecosystem parameters such as the maximum photosynthesis rate of the sphagnum as well as the extent of soil and plant respiration. Miniaturized Raman gas spectroscopy was proven to be an extremely versatile analytical technique that allows for onsite multigas analysis in high temporal resolution. Therefore it is an urgently needed tool for elucidation of complex biochemical processes especially in climate-sensitive ecosystems and consequently for the estimation of climate-relevant gas budgets.

  20. Influence of peat-bog fire on physical properties of peat-mull soils

    NASA Astrophysics Data System (ADS)

    Stabryla, J.; Lipka, K.

    2009-04-01

    In recent years in Poland disseminated the curse of grassland (either peat meadows) burning. Peat-bogs drained long time ago, where peat-mull soils occur are subjected on fire in particular, because they are often dried. After burned peat remain pits various depth and land irregularity. The aim of the work is morphological characteristics of soil profiles and comparison of chosen physical properties of peat-mull soils on former fire and adjacent area. Research was carried out on the mid-forest peat-bog Wielkie Bloto in Puszcza Niepolomicka. The method used in the work is routinely accepted in soil science. The results show that values of ash content, density and moisture are higher than the ones for soils of adjacent areas. In top stratum of post fire soils bulk density is lower in comparison with upper layers of adjacent soils. Contractility of soils degraded by fire is lower than for soils of adjacent areas.

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

    NASA Astrophysics Data System (ADS)

    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.

  2. Properties and structure of peat humic acids depending on humification and precursor biota in bogs

    NASA Astrophysics Data System (ADS)

    Klavins, Maris; Purmalis, Oskars

    2013-04-01

    Humic substances form most of the organic component of soil, peat and natural waters, but their structure and properties very much differs depending on their source. The aim of this study is to characterize humic acids from raised bog peat profiles to evaluate the homogeneity of humic acids isolated from the bog bodies and study peat humification impact on properties of humic acids. A major impact on the structure of peat humic acids have raised bog biota (dominantly represented by bryophytes of different origin) void of lignin. For characterization of peat humic acids their elemental (CHNOS), functional (-COOH, phenolic OH) analysis, spectroscopic characterization (UV, fluorescence, FTIR, 1H NMR, CP/MAS 13C NMR, ESR) and degradation studies (Py-GC/MS) were done. Peat humic acids (HA) 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, but thermodynamically more stable aromatic and polyaromatic structures emerge. Comparatively, the studied peat HAs are at the start of the transformation process of living organic matter. Concentrations of carboxyl and phenolic hydroxyl groups changes depending on the depth of peat from which HAs have been isolated: and carboxylic acidity is increasing with depth of peat location and the humification degree. The ability to influence the surface tension of peat humic acids isolated from a well-characterized bog profile demonstrates dependence on age and humification degree. With increase of the humification degree and age of humic acids, their molecular complexity and ability to influence surface tension decreases; even so, the impact of the biological precursor (peat-forming bryophytes and plants) can be identified.

  3. Radioactive deposits in California

    USGS Publications Warehouse

    Walker, George W.; Lovering, Tom G.

    1954-01-01

    containing rare earths. Secondary uranium minerals have been found as fracture coatings and as disseminations in various types of wall rock, although they are largely confined to areas of Tertiary volcanic rocks. Probably the uranium in the uraniferous deposits in California is related genetically to felsic crystalline rocks and felsic volcanic rocks; the present distribution of the secondary uranium minerals has been controlled, in part, by circulating ground waters and probably, in part, by magmatic waters related to the Tertiary volcanic activity. The thorium minerals are genetically related to the intrusion of pegmatite and plutonic crystalline rocks. None of the known deposits of radioactive minerals in California contain marketable reserves of uranium or thorium ore under economic conditions existing in 1952. With a favorable local market small lots of uranium ore may be available in the following places: the Rosamund prospect, the Rafferty and Chilson properties, the Lucky Star claim, and the Yerih group. The commercial production of thorium minerals will be possible, in the near future, only if these minerals can be recovered cheaply as a byproduct either from the mining of rare earths minerals at Mountain Pass or as a byproduct of placer mining for gold.

  4. [Detection of representatives of the Planctomycetes in Sphagnum peat bogs by molecular and cultivation methods].

    PubMed

    Kulichevskaia, I S; Pankratov, T A; Dedysh, S N

    2006-01-01

    By means of fluorescence in situ hybridization with 16S rRNA-targeted oligonucleotide probes (FISH), it has been shown that members of the phylum Planctomycetes represent a numerically significant bacterial group in boreal Sphagnum peat bogs. The population size of planctomycetes in oxic layers of the peat bog profile was in the range of 0.4-2.0 x 10(7) cells per g of wet peat, comprising 4 to 13% of the total bacterial cell number. A novel effective approach that combined a traditional cultivation technique with FISH-mediated monitoring of the target organism during the isolation procedure has been developed for the isolation of planctomycetes. Using this approach, we succeeded in isolating several peat-inhabiting planctomycetes in a pure culture. Sequencing of the 16S rRNA genes from two of these isolates, strains A10 and MPL7, showed that they belonged to the planctomycete lineages defined by the genera Gemmata and Planctomyces, respectively. The 16S rRNA gene sequence similarity between strains A10 and MPL7 and the phylogenetically closest organisms, namely, Gemmata obscuriglobus and Planctomyces limnophilus, was only 90%. These results suggest that the indigenous planctomycetes inhabiting Sphagnum peat bogs are so far unknown organisms.

  5. Carbon balance of a European mountain bog at contrasting stages of regeneration.

    PubMed

    Bortoluzzi, Estelle; Epron, Daniel; Siegenthaler, Andy; Gilbert, Daniel; Buttler, Alexandre

    2006-01-01

    Carbon dioxide and methane (CH4) fluxes were measured in a cutover bog of the Jura Mountains (France) together with biotic and abiotic variables for two entire vegetation periods in order to compare the carbon balance of the bog at three stages of regeneration. Among all factors, air temperature and vegetation index (including leaf area of vascular plants, bryophyte density and bryophyte desiccation) were the two main determinants of ecosystem respiration and gross photosynthesis at light saturation. During 2004 and 2005, the vegetated plots acted as carbon sinks. Net carbon exchange ranged between 67 and 166 g C m(-2) yr(-1) for the Eriophorum-dominated plots and between 93 and 183 g C m(-2) yr(-1) for the Sphagnum-dominated plots. The bare peat plots represented a net carbon source (between -19 and -32 g C m(-2) yr(-1)). Methane fluxes accounted for a very small part of the total carbon efflux (< 2%). The recovery of vegetation in our naturally regenerating bog was beneficial for the carbon sequestration after the relatively short period of 20 yr.

  6. Evaluating cumulative effects of disturbance on the hydrologic function of bogs, fens, and mires

    SciTech Connect

    Siegel, D.I.

    1988-01-01

    Few quantitative studies have been done on the hydrology of fens, bogs, and mires and, consequently, any predictions of the cumulative impacts of disturbances on their hydrologic functions is extremely difficult. Bogs and fens are, in a sense, hydrobiologic systems, and any evaluation of cumulative impacts on them will have to consider the complicated interactions, barely understood, among the wetland hydrology, water chemistry, and biota, and place the effect of individual wetland impacts within the context of the cumulative impacts contributed to the watershed from other geomorphic areas and land uses. It is difficult to evaluate the potential cumulative impacts on wetland hydrology because geologic settings of wetlands are often complex and the methods used to measure wetland stream flow, ground-water flow, and evapotranspiration are inexact. Their very scale makes it difficult to quantify the hydrologic function accurately. The paper reviews current understanding of the hydrologic function of bogs, fens, and mires at different scales and in different physiographic settings, and presents hypotheses on potential cumulative impacts on the hydrologic function that might occur with multiple disturbances.

  7. The morphology of peat bog surfaces on Hermansenøya, NW Svalbard

    NASA Astrophysics Data System (ADS)

    Jaworski, Tomasz

    2017-03-01

    This article analyses the surface morphology of the arctic peat bogs occurring on Hermansenøya, a small island in the Forlandsundet, NW Svalbard. Six small, shallow peat bogs on the island show different microrelief features formed by ice-segregation as well as thermokarst and thermo-erosion processes. On the peat bogs the following forms have been identified: aggradational, associated with the growth of different types of ground ice (frost peat mounds, peat plateaus, polygonal peat plateaus, networks of ice-wedge polygons); and degradational, associated with thermokarst (symmetrically developed residual peat mounds and the furrows in between) and thermo-erosion (channels of niveo-fluvial streams). Some importance can also be attributed to aeolian processes, i.e. snow drifting from the tops of convex relief features for aggradational forms. Lack of insulating snow cover significantly increases frost penetration depth, promoting cryosuction and/or ice growth at the base of a frozen core. The oldest preserved forms and structures, frost peat mounds with an ice-peat core and ice-wedge polygons, developed during climatic cooling at the turn of the Subboreal and Subatlantic (c. 3.0-2.5 ka BP). Thermokarst mounds are younger, associated with warmer periods after the Little Ice Age (the warmer 1920s). Channels of niveo-fluvial streams are being shaped today.

  8. A comparison of antimony and lead profiles over the past 2500 years in Flanders Moss ombrotrophic peat bog, Scotland.

    PubMed

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

    2005-12-01

    Two cores collected in 2001 and 2004 from Flanders Moss ombrotrophic peat bog in central Scotland were dated (14C, 210Pb) and analysed (ICP-OES, ICP-MS) to derive and compare the historical atmospheric deposition records of Sb and Pb over the past 2500 years. After correction, via Sc, for contributions from soil dust, depositional fluxes of Sb and Pb peaked from ca. 1920-1960 A.D., with >95% of the anthropogenic inventories deposited post-1800 A.D. Over the past two centuries, trends in Sb and Pb deposition have been broadly similar, with fluctuations in the anthropogenic Sb/Pb ratio reflecting temporal variations in the relative input from emission sources such as the mining and smelting of Pb ores (in which Sb is commonly present, as at Leadhills/Wanlockhead in southern Scotland), combustion of coal (for which the Sb/Pb ratio is approximately an order of magnitude greater than in Pb ores) and exhaust emissions (Pb from leaded petrol) and abrasion products from the brake linings (Sb from heat-resistant Sb compounds) of automobiles. The influence of leaded petrol has been most noticeable in recent decades, firstly through the resultant minima in Sb/Pb and 206Pb/207Pb ratios (the latter arising from the use of less radiogenic Australian Pb in alkylPb additives) and then, during its phasing out and the adoption of unleaded petrol, complete by 2000 A.D., the subsequent increase in both Sb/Pb and 206Pb/207Pb ratios. The extent of the 20th century maximum anthropogenic enrichment of Sb and Pb, relative to the natural Sc-normalised levels of the Upper Continental Crust, was similar at approximately 50- to 100-fold. Prior to 1800 A.D., the influence of metallurgical activities on Sb and Pb concentrations in the peat cores during both the Mediaeval and Roman/pre-Roman periods was discernible, small Sb and Pb peaks during the latter appearing attributable, on the basis of Pb isotopic composition, to the mining/smelting of Pb ores indigenous to Britain.

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

    NASA Astrophysics Data System (ADS)

    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 (<100 km). While dust deposition was reduced during the second event (5300-4370 cal yr BP), this is the most distinct in terms of its source character with [Eu/Eu∗]UCC revealing the input of plagioclase feldspar from a local source, possibly active during this stormier period. The third (2380-2200 cal yr BP) and fourth (1275-1080 cal yr BP) events are much shorter in duration and the presence of 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

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

    NASA Astrophysics Data System (ADS)

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

    2002-07-01

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

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

    NASA Astrophysics Data System (ADS)

    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

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

    NASA Astrophysics Data System (ADS)

    Smidt, Geerd; Tänzer, Detlef

    2013-04-01

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

  13. The importance of dissolved free oxygen during formation of sandstone-type uranium deposits

    USGS Publications Warehouse

    Granger, Harry Clifford; Warren, C.G.

    1979-01-01

    One factor which distinguishes t, he genesis of roll-type uranium deposits from the Uravan Mineral Belt and other sandstone-type uranium deposits may be the presence and concentration of dissolved free oxygen in the ore-forming. solutions. Although dissolved oxygen is a necessary prerequisite for the formation of roll-type deposits, it is proposed that a lack of dissolved oxygen is a prerequisite for the Uravan deposits. Solutions that formed both types of deposits probably had a supergene origin and originated as meteoric water in approximate equilibrium with atmospheric oxygen. Roll-type deposits were formed where the Eh dropped abruptly following consumption of the oxygen by iron sulfide minerals and creation of kinetically active sulfur species that could reduce uranium. The solutions that formed the Uravan deposits, on the other hand, probably first equilibrated with sulfide-free ferrous-ferric detrital minerals and fossil organic matter in the host rock. That is, the uraniferous solutions lost their oxygen without lowering their Eh enough to precipitate uranium. Without oxygen, they then. became incapable of oxidizing iron sulfide minerals. Subsequent localization and formation of ore bodies from these oxygen-depleted solutions, therefore, was not necessarily dependent on large reducing capacities.

  14. The formation of basal-type uranium deposits in south central British Columbia

    SciTech Connect

    Boyle, D.R.

    1982-08-01

    The basal-type uranium deposits in south central British Columbia occur within unconsolidated, late Miocene fluvial paleochannel sediments that overlie major fault zones within the Okanagan Highlands Intrusive Complex. Five uranium deposits have been outlined to date, of which the Blizzard (4,020 metric tons U) and Tyee (650 metric tons U) are the largest. The basement intrusive complex underlying the deposits varies in age from early Cretaceous to Eocene and is comprised of quartz monzonite, granodiorite, Coryell monzonite, porphyritic granite, and pegmatite. Uranium mineralization is present in the form of uranous (ningyoite) or uranyl (saleeite, autunite) phosphates coating clastic grains and filling voids. Because of very strong reducing conditions related to large concentrations of marcasite and organic material, ningyoite is the only uranium mineral in the Tyee deposit, whereas the Blizzard deposit contains a more complex assemblage of minerals (saleeite, autunite, ningyoite). The observed paragenetic sequence of mineral precipitation in the Blizzard deposit (autunite-saleeite-ningyoite) indicates that the uranyl minerals, saleeite and autunite, are primary. Investigations of the source of the ore-forming elements (U, Ca, Mg, PO/sub 4/) showed the deposits to be formed by the infiltration into fluvial sediments of deep-seated, structurally controlled, ground waters that migrated in a well-developed regional hydrologic system within the Complex. Research indicates that the ore-forming ground waters were cold, slightly bicarbonated (150-400 ppm), highly uraniferous (10-50 ppb), and slightly oxidizing (dissolved oxygen = 2-4 ppm).

  15. Summary of reconnaissance for radioactive deposits in Alaska, 1945-1954, and an appraisal of Alaskan uranium possibilities

    USGS Publications Warehouse

    Wedow, Helmuth

    1956-01-01

    carnotite-type deposits. The chief of these areas is the Alaska Peninsula-Cook Inlet area which encompasses most of the reported occurrences of the prospectors' carnotite-type samples. Alaska is also potentially favorable for the occurrence of large bodies of the very low-grade uraniferous sedimentary rocks, such as phosphorites and black shales. This type of deposit, however, has not received much study because of the emphasis on the search for bonanza-type high-grade ores. Uraniferous phosphorites similar to those of Idaho, Montana, and Wyoming occur in northern Alaska on the north flank of the Brooks Range; black shales comparable to the uraniferous shales of the Chattanooga formation of southeastern United States have been noted along the Yukon River near the international boundary. Placer deposits in Alaska have some small potential for the production of the radioactive elements as byproducts of gold- and tin-placer mining. the placer area believed to have the relatively greatest potential in Alaska lies in the Kahiltna River valley where concentrates are known to contain such commercial minerals as ilmenite, cassiterite, platinum, and gold in addition to uranothorianite and monazite. The possibilities of the natural fluids--water and petroleum--have not yet been tested in Alaska to any great extent. Studies of fluids are in progress to determine whether they may be used to discover and define areas potentially favorable for the occurrence of uraniferous lodes.

  16. Embryogenesis and tadpole description of Hyperolius castaneus Ahl, 1931 and H. jackie Dehling, 2012 (Anura, Hyperoliidae) from montane bog pools

    PubMed Central

    Lehr, Edgar; Dehling, J. Maximilian; Greenbaum, Eli; Sinsch, Ulrich

    2015-01-01

    Abstract Tadpoles of Hyperolius castaneus and Hyperolius jackie were found in the Nyungwe National Park in Rwanda and adjacent areas. Tadpoles of both species were identified by DNA-barcoding. At the shore of a bog pool three clutches of Hyperolius castaneus of apparently different age, all laid on moss pads (Polytrichum commune, Isotachis aubertii) or grass tussocks (Andropogon shirensis) 2–5 cm above the water level, were found. One clutch of Hyperolius castaneus was infested by larval dipterid flies. The most recently laid clutch contained about 20 eggs within a broad egg-jelly envelope. The eggs were attached to single blades of a tussock and distributed over a vertical distance of 8 cm. A pair of Hyperolius castaneus found in axillary amplexus was transported in a plastic container to the lab for observation. The pair deposited a total of 57 eggs (15 eggs attached to the upper wall of the transport container, 42 eggs floated in the water). Embryogenesis of the clutch was monitored in the plastic container at 20 ± 2 °C (air temperature) and documented by photos until Gosner Stage 25. The description of the tadpole of Hyperolius castaneus is based on a Gosner Stage 29 individual from a series of 57 tadpoles (Gosner stages 25–41). The description of the tadpole of Hyperolius jackie is based on a Gosner Stage 32 individual from a series of 43 tadpoles (Gosner stages 25–41). Egg laying behavior and embryogenesis are unknown for Hyperolius jackie. The labial tooth row formula for both species is 1/3(1) with a narrow median gap of the tooth row. Variation in external morphology was observed in size and labial tooth row formula within the species. With the tadpole descriptions of Hyperolius castaneus and Hyperolius jackie, 36 tadpoles of the 135 known Hyperolius species have been described, including five of the eleven Hyperolius species known from Rwanda. PMID:26798309

  17. Embryogenesis and tadpole description of Hyperolius castaneus Ahl, 1931 and H. jackie Dehling, 2012 (Anura, Hyperoliidae) from montane bog pools.

    PubMed

    Lehr, Edgar; Dehling, J Maximilian; Greenbaum, Eli; Sinsch, Ulrich

    2015-01-01

    Tadpoles of Hyperolius castaneus and Hyperolius jackie were found in the Nyungwe National Park in Rwanda and adjacent areas. Tadpoles of both species were identified by DNA-barcoding. At the shore of a bog pool three clutches of Hyperolius castaneus of apparently different age, all laid on moss pads (Polytrichum commune, Isotachis aubertii) or grass tussocks (Andropogon shirensis) 2-5 cm above the water level, were found. One clutch of Hyperolius castaneus was infested by larval dipterid flies. The most recently laid clutch contained about 20 eggs within a broad egg-jelly envelope. The eggs were attached to single blades of a tussock and distributed over a vertical distance of 8 cm. A pair of Hyperolius castaneus found in axillary amplexus was transported in a plastic container to the lab for observation. The pair deposited a total of 57 eggs (15 eggs attached to the upper wall of the transport container, 42 eggs floated in the water). Embryogenesis of the clutch was monitored in the plastic container at 20 ± 2 °C (air temperature) and documented by photos until Gosner Stage 25. The description of the tadpole of Hyperolius castaneus is based on a Gosner Stage 29 individual from a series of 57 tadpoles (Gosner stages 25-41). The description of the tadpole of Hyperolius jackie is based on a Gosner Stage 32 individual from a series of 43 tadpoles (Gosner stages 25-41). Egg laying behavior and embryogenesis are unknown for Hyperolius jackie. The labial tooth row formula for both species is 1/3(1) with a narrow median gap of the tooth row. Variation in external morphology was observed in size and labial tooth row formula within the species. With the tadpole descriptions of Hyperolius castaneus and Hyperolius jackie, 36 tadpoles of the 135 known Hyperolius species have been described, including five of the eleven Hyperolius species known from Rwanda.

  18. [Bacteria of the genus Burkholderia as a typical component of the microbial community of sphagnum peat bogs].

    PubMed

    Belova, S E; Pankratov, T A; Dedysh, S N

    2006-01-01

    Bacteria of the genus Burkholderia are a typical component of the microbial complex of sphagnum peat bogs and constitute a substantial portion of the aerobic chemoorganotrophic isolates which are routinely obtained from these environments on acidic nutrient media. The ecophysiological characteristics of the 27 strains of such organisms, which were isolated from the peat of acidic sphagnum bogs of the boreal and tundra zones of Russia, Canada, and Estonia, were investigated in the present paper. The overwhelming majority of the Burkholderia strains isolated from these bogs were phylogenetically close to the species B. glathei, B. phenazinium, B. fungorum, and B. caryophylli, the typical inhabitants of soil and plant rhizosphere. The bog isolates utilized a broad range of substrates as carbon and energy sources, including organic acids, sugars, polyalcohols, and certain aromatic compounds. All the strains studied were capable of growth on nitrogen-free media. They developed in the pH ranges of 3.5 to 7.4 and from 3 to 37 degrees C, with the optima at pH 5-7 and 11-23 degrees C, respectively. They were therefore moderately acidophilic, psychroactive, dinitrogen-fixing microorganisms well adapted to the conditions of acidic northern sphagnum bogs.

  19. Reconstructing the environmental impact of smelters using Pb isotope analyses of peat cores from bogs: Flin Flon, Manitoba and Harjavalta, Finland

    NASA Astrophysics Data System (ADS)

    Shotyk, W.

    2012-04-01

    provide a remarkably similar evolution of Pb isotopes, reaching values as low as 206Pb/207Pb = 1.151 (AD 1982) and 1.148 (AD 1984), respectively. At HAR, the minimum values are lower (206Pb/207Pb = 1.120) and earlier (AD 1954 -1967), presumably because of emissions from the smelter. The Pb concentrations in the porewaters from HAR are approximately an order of magnitude greater than the other sites, and the 206Pb/207Pb values significantly lower (ca. 1.12 vs. 1.15), because of the combined effects of greater Pb deposition and surface water acidification (pH 3.5 versus pH 4.0 in the other bogs).

  20. Chemical composition, pH, and redox state of sulfur and iron in complete vertical porewater profiles from two Sphagnum peat bogs, Jura Mountains, Switzerland

    NASA Astrophysics Data System (ADS)

    Steinmann, Philipp; Shotyk, William

    1997-03-01

    inorganic acids are equal in importance. Unidentified organic S species accounted for 90-99% of total dissolved sulfur (S T) in the porewaters at TGe, with SO 42- and HS - the dominant inorganic species; S species with intermediate oxidation states such as SO 32- and S 2O 32- were always less than the detection limit of approximately 0.4 μM. At TGe the sulfate concentrations exceeded those of sulfide, with 1.25 and 0.25 μM, respectively, being typical. At EGr, S T and SO 42- were comparable to the waters at TGe, but HS - at EGr was always less than the detection limit of 0.15 μM. At both sites dissimilatory sulfate reduction is limited by the low concentrations of sulfate supplied to the bog surfaces (i.e., atmospheric deposition only), and the uptake of sulfate and its conversion to organic S compounds by the living plants. Despite the anoxic condition of the waters, the ratio of Fe(III) T to Fe(II) T was always high: at EGr this ratio was generally 1:1, and even in the sulfidic waters at TGe the ratio was 1:3. PHREEQE was used to calculate the effect of complex-forming organic ligands on {Fe 3+} and {Fe 2+} in these porewaters. The relatively high ratios of Fe(III) T compared to Fe(II) T can be explained in terms of the much greater thermodynamic stability of the organic complexes of Fe 3+ compared to those of Fe 2+.

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

    PubMed Central

    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. PMID:22768100

  2. Spatial variation in rates of carbon and nitrogen accumulation in a boreal bog

    SciTech Connect

    Ohlson, M.; Oekland, R.H.

    1998-12-01

    Although previous studies hint at the occurrence of substantial spatial variation in the accumulation rates of C and N in bogs, the extent to which rates may vary on high-resolution spatial and temporal scales is not known. A main reason for the lack of knowledge is that it is problematic to determine the precise age of peat at a given depth. The authors determined rates of carbon and nitrogen accumulation in the uppermost decimeters of a bog ecosystem using the pine method, which enables accurate dating of surface peat layers. They combined accumulation data with numerical and geostatistical analyses of the recent vegetation to establish the relationship between bog vegetation and rate of peat accumulation. Use of a laser technique for spatial positioning of 151 age-determined peat cores within a 20 x 20 m plot made it possible to give the first tine-scaled account of spatial and temporal variation in rates of mass, carbon, and nitrogen accumulation during the last century. Rates of C and N accumulation were highly variable at all spatial scales studied. For example, after {approximately}125 yr of peat growth, C and N accumulation varied by factors of five and four, respectively, from 25 to 125 g/dm{sup 2} for C, and from 0.7 to 2.6 g/dm{sup 2} for N. It takes 40 yr of peat accumulation before significant amounts of C are lost through decay. Hummocks built up by Sphagnum fuscum and S. rubellum were able to maintain average rates of C accumulation that exceed 2 g{center_dot}dm{sup {minus}2}{center_dot} yr{sup {minus}1} during 50 yr of growth. The authors argue that data on spatial variation in rates of C accumulation are necessary to understand the role of boreal peatlands in the greenhouse effect and global climate.

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

    PubMed

    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.

  4. Bog blueberry anthocyanins alleviate photoaging in ultraviolet-B irradiation-induced human dermal fibroblasts.

    PubMed

    Bae, Ji-Young; Lim, Soon Sung; Kim, Sun Ju; Choi, Jung-Suk; Park, Jinseu; Ju, Sung Mi; Han, Seoung Jun; Kang, Il-Jun; Kang, Young-Hee

    2009-06-01

    Fruits of bog blueberry (Vaccinium uliginosum L.) are rich in anthocyanins that contribute pigmentation. Anthocyanins have received much attention as agents with potentials preventing chronic diseases. This study investigated the capacity of anthocyanin-rich extract from bog blueberry (ATH-BBe) to inhibit photoaging in UV-B-irradiated human dermal fibroblasts. BBe anthocyanins were detected as cyanidin-3-glucoside, petunidin-3-glucoside, malvidin-3-glucoside, and delphinidin3-glucoside. ATH-BBe attenuated UV-B-induced toxicity accompanying reactive oxygen species (ROS) production and the resultant DNA damage responsible for activation of p53 and Bad. Preincubation of ATH-BBe markedly suppressed collagen degradation via blunting production of collagenolytic matrix metalloproteinases (MMP). Additionally, ATH-BBe enhanced UV-B-downregulated procollagen expression at transcriptional levels. We next attempted to explore whether ATH-BBe mitigated the MMP-promoted collagen degradation through blocking nuclear factor kappaB (NF-kappaB) activation and MAPK-signaling cascades. UV-B radiation enhanced nuclear translocation of NF-kappaB, which was reversed by treatment with ATH-BBe. The UV-B irradiation rapidly activated apoptosis signal-regulating kinase-1 (ASK-1)-signaling cascades of JNK and p38 mitogen-activated protein kinase (p38 MAPK), whereas ATH-BBe hampered phosphorylation of c-Jun, p53, and signal transducers and activators of transcription-1 (STAT-1) linked to these MAPK signaling pathways. ATH-BBe diminished UV-B augmented-release of inflammatory interleukin (IL)-6 and IL-8. These results demonstrate that ATH-BBe dampens UV-B-triggered collagen destruction and inflammatory responses through modulating NF-kappaB-responsive and MAPK-dependent pathways. Therefore, anthocyanins from edible bog blueberry may be protective against UV-induced skin photoaging.

  5. Impact of environmental factors on dissolved organic carbon concentrations in German bogs under grassland

    NASA Astrophysics Data System (ADS)

    Frank, Stefan; Tiemeyer, Bärbel; Freibauer, Annette

    2013-04-01

    Peatlands cover about 5% of Germany's land area. Agricultural use combined with drainage increases the greenhouse gas emissions and alters the dissolved organic carbon (DOC) concentrations in the soil- and groundwater of these ecosystems. Cycling of DOC is influenced by a complex interaction of environmental factors such as peat characteristics, groundwater level, meteorological conditions, pH-value and ionic strength. Reasons for elevated DOC concentrations are debated in literature, but only a few studies on the dynamic of DOC in raised bogs in Germany have been conducted so far. In Germany, raised bogs are mainly used as grassland. Therefore, five grassland study sites and one natural reference have been selected. The bog "Ahlenmoor" has a deep, medium to weakly decomposed peat layer. There, three study sites represent different land use intensities with a corresponding groundwater table (intensive grassland, extensive grassland, natural reference). The bog relict "Großes Moor" is characterised by a shallow amorphous peat layer, which is partly mixed with sand. There, three sites in an extensive grassland were chosen to study the effects of soil carbon concentrations (9 to 48 %) and groundwater levels. At each site, nine suction plates (three replicates in each depth) and three tensiometers were installed in 15, 30 and 60 cm. Soil water was sampled fortnightly from June 2011 to December 2012 and analysed for electrical conductivity, pH-value and DOC concentration. Compared to most literature values, DOC concentrations at our study sites were very high (on average, 197 to 55 mg/L). At the "Ahlenmoor", an increase in agricultural intensity and a lower groundwater table increases both the DOC concentrations and their variability in the soil water in order intensive grassland > extensive grassland > natural site. Surprisingly, soil carbon concentration and groundwater table gradients as investigated in the "Großes Moor" did only lead to minor differences in the

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

    NASA Astrophysics Data System (ADS)

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

    2016-04-01

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

  7. Historical peat loss explains limited short-term response of drained blanket bogs to rewetting.

    PubMed

    Williamson, Jennifer; Rowe, Edwin; Reed, David; Ruffino, Lucia; Jones, Peter; Dolan, Rachel; Buckingham, Helen; Norris, David; Astbury, Shaun; Evans, Chris D

    2017-03-01

    This study assessed the short-term impacts of ditch blocking on water table depth and vegetation community structure in a historically drained blanket bog. A chronosequence approach was used to compare vegetation near ditches blocked 5 years, 4 years and 1 year prior to the study with vegetation near unblocked ditches. Plots adjacent to and 3 m away from 70 ditches within an area of blanket bog were assessed for floristic composition, aeration depth using steel bars, and topography using LiDAR data. No changes in aeration depth or vegetation parameters were detected as a function of ditch-blocking, time since blocking, or distance from the ditch, with the exception of non-Sphagnum bryophytes which had lower cover in quadrats adjacent to ditches that had been blocked for 5 years. Analysis of LiDAR data and the observed proximity of the water table to the peat surface led us to conclude that the subdued ecosystem responses to ditch-blocking were the result of historical peat subsidence within a 4-5 m zone either side of each ditch, which had effectively lowered the peat surface to the new, ditch-influenced water table. We estimate that this process led to the loss of around 500,000 m(3) peat within the 38 km(2) study area following drainage, due to a combination of oxidation and compaction. Assuming that 50% of the volume loss was due to oxidation, this amounts to a carbon loss of 11,000 Mg C over this area, i.e. 3 Mg C ha(-1). The apparent 'self-rewetting' of blanket bogs in the decades following drainage has implications for their restoration as it suggests that there may not be large quantities of dry peat left to rewet, and that there is a risk of inundation (potentially leading to high methane emissions) along subsided ditch lines. Many peatland processes are likely to be maintained in drained blanket bog, including support of typical peatland vegetation, but infilling of lost peat and recovery of original C stocks are likely to take longer than is

  8. Unexpected DNA-fingerprinting pattern in a deep peat bog: evidence for methanotrophs at the bottom?

    NASA Astrophysics Data System (ADS)

    Steinmann, P.; Rossi, P.; Huon, S.; Eilrich, B.; Casati, S.

    2003-04-01

    With the goal of a better understanding of the fate of methane in the deep layers of peat bogs, we analysed the microbial 16S rDNA gene pool and measured the stable carbon isotope composition of bulk peat of a deep (6 m) peat bog profile (Etang de la Gruyère, Switzerland). Both Bacterial and Archaean communities were assessed using respectively TTGE (Temporal Temperature Gradient Electrophoresis) and SSCP (Single Strand Conformation Polymorphism), with fragments of the V1-V3 region of the 16S rDNA gene. The "relative diversity" shown in the TTGE AND SSCP gel patterns is presented using indices and band numbers per sample (Simpson evenness). PCA was calculated on the basis of the intensities of all bands found in the TTGE and SSCP fingerprinting profiles. These DNA fingerprinting patterns reveal the presence of a structured microbial community throughout the whole depth profile. Clear differences can be observed between the communities found in the near surface layers and those found at depth. Surprisingly, for both Archaean and Bacterial communities, the deepest samples display a high similarity level with those found in the first 20 centimeters. The δ13C values of the peat are relatively constant from the surface of the bog down to a depth of 5 m (values between 25.5 ppm and 26.5 ppm). Below 5 m the values decrease considerably with depth ( 28.5 ppm). As a working hypothesis to explain the two observations, we consider the possibility of the presence of methanotrophs in the deepest parts of the bogs. The electron acceptors needed for methane oxidation could be derived from lateral advection of less reducing groundwater. However, available pore water analyses suggest that neither molecular oxygen, nor sulfate or nitrate are present. One possible oxidising agent would be trivalent iron (solid or colloidal). Indeed are the iron concentrations in the deeper pore waters are elevated. Such deep methanotrophic microbial community could be similar to those found near

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

    NASA Astrophysics Data System (ADS)

    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

  10. 137Cs in fungal sporocarps in relation to vegetation in a bog, pine swamp and forest along a transect.

    PubMed

    Vinichuk, M; Rosén, K; Dahlberg, A

    2013-01-01

    In this study, we estimated the relative importance of vegetation and fungi for radiocesium uptake and biological retention in adjacent bog, pine swamp, and forest. The measurements for (137)Cs activity concentration in sporocarps (i.e. fruitbodies of fungi) and vegetation along a bog to forest transect were combined with complementary published data to calculate estimates. Aboveground vegetation comprised 17.7% of the total fallout-derived radiocesium in the system in bog, 16.5% in pine swamp, and 40.6% in forest. In fungal sporocarps grown along a gradient, (137)Cs activity comprised <0.001% of the total radiocesium for peat bog, <0.02% for pine swamp, and 0.11% for forest. Total (137)Cs activity in sporocarps increased along the gradient due to increased production of sporocarps in the presence of trees from 0.006 (bog), 0.097 (pine swamp) and 0.67 (forest) g dwt m(-2). Based on calculation of the total vegetation biomass and through relationships between fungal biomass in sporocarps and as mycelia in soil, the total (137)Cs activity located in fungi was estimated as 0.1% in bog, 2% in pine swamp, and 11% in forest. An analysis of the time-dependency of (137)Cs in the sporocarps in forest between 1990 and 2011 suggested an ecological half-life for (137)Cs between 8 and 13 years. Although fungi comprised a relatively small fraction of the total radiocesium in the systems, its activity decreased slowly with time, and ecological residence time for (137)Cs in sporocarps of fungi was long, suggesting they will continue to contribute to the accumulation and cycling of this radionuclide in forest.

  11. High-resolution Record of Holocene Climate, Vegetation, and Fire from a Raised Peat Bog, Prince Edward Island, Canadian Maritimes

    NASA Astrophysics Data System (ADS)

    Peros, M. C.; Chan, K.; Ponsford, L.; Carroll, J.; Magnan, G.

    2014-12-01

    Raised peat bogs receive all precipitation and nutrients from the atmosphere and are thus widely used archives for information on past environments and climates. In this paper we provide high-resolution multi-proxy data from a raised bog from northeastern Prince Edward Island, located in the Gulf of St. Lawrence, Canada. We studied testate amoeba (a proxy for water table depth), macrocharcoal (a proxy for local-scale fire), peat humification (a proxy for decomposition), plant macrofossils (indicative of local-scale vegetation), and organic matter content (yielding carbon accumulation rates) from a 5.5 m long core lifted from the center of Baltic Bog. Eleven AMS radiocarbon dates show that peat accumulation began before 9000 cal yr BP and continued almost uninterrupted until the present. The macrofossil data show that a transition from a sedge-dominated fen to a sphagnum-dominated bog occurred around 8000 cal yr BP, and sphagnum remained dominant in the bog throughout most of the Holocene. A testate amoeba-based reconstruction of water table depth indicates that conditions were drier during the early Holocene (~8000 to 5000 cal yr BP) and became gradually wetter into the late Holocene. In addition, a number of higher frequency shifts in precipitation are inferred throughout the Holocene on the basis of the testate amoeba and humification results. The macrocharcoal evidence indicates fire—probably in the surrounding forest—was relatively more common during the early Holocene, perhaps due to drier climate conditions. A large influx of charcoal at around 2000 cal yr BP suggests the presence of one or more major fires at this time, and a concurrent decrease in the rate of peat accumulation indicates the fire may have affected the bog itself. The data from Baltic Bog is broadly comparable to other proxy data (in particular pollen studies) from the Canadian Maritimes. This work is important because it: 1) helps us better understand the role of hydroclimatic

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

    NASA Astrophysics Data System (ADS)

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

    2013-04-01

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

  13. 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

    NASA Astrophysics Data System (ADS)

    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

  14. Multiproxy investigation of climatic changes and human activities in a Baltic bog (N. Poland) during the last millennium.

    NASA Astrophysics Data System (ADS)

    de Vleeschouwer, François; Fagel, Nathalie; Piotrowska, Natalia; Sikorski, Jarek; Pawlyta, Jacek; Cheburkin, Andriy; Lamentowicz, Mariusz; Pazdur, Anna; Mattielli, Nadine; Renson, Virginie

    2010-05-01

    We present a multiproxy study carried out on a peat core retrieved from Słowińskie Błota bog (Pomerania, N-Poland). Several organic (palynology, plant macrofossils, testate amoebae, d13C) and inorganic (elemental geochemistry, lead isotopes) proxies were coupled to 210Pb-14C age-modelling in order to discriminate climatic and anthropogenic signals. Reconstruction of dust fluxes through time has remained a challenge, especially for tracing the nature of climatic changes. Although the idea of enhanced erosion conditions and storminess is commonly discussed, the conditions for dust deposition in peatlands over Europe during, for example, the ‘Little Ice Age' (LIA), are rarely favourable. Indeed the natural forest cover over Europe was much more important than nowadays, preventing dust deposition. Northern Poland, near the Baltic shore, was deforested just before the LIA (around AD 1100), and therefore constitutes a key area for the reconstruction of LIA climatic change. Our study of organic proxies evidences the LIA and is combined to our inorganic geochemical approach to validate our dust record. Overall, both organic and inorganic proxies show that LIA climatic changes are in good agreement with other records from Poland and NE Europe within a ca. 50yrs uncertainty. The severity of the LIA does however not affect the dynamism of mining activities over the last millennium. Indeed, during the LIA, Poland is experiencing its economical and cultural apogee, which can be seen by an increase in lead enrichment factors interpreted as an increase in mining activities. Lead, Zn, Cu, Ni concentrations and Pb isotopic ratios show that Polish Pb-Zn ores and coal were the main sources of Pb, as well as other heavy metals and S over Northern Poland until the industrial revolution. During the last century, leaded gasoline also contributed to anthropogenic Pb input over Poland. Coal and Pb-Zn ores, however, remained important sources of pollution in Eastern European countries

  15. Trench Logs and Scarp Data from an Investigation of the Steens Fault Zone, Bog Hot Valley and Pueblo Valley, Humboldt County, Nevada

    USGS Publications Warehouse

    Personius, Stephen F.; Crone, Anthony J.; Machette, Michael N.; Kyung, Jai Bok; Cisneros, Hector; Lidke, David J.; Mahan, Shannon

    2006-01-01

    Introduction: This report contains field and laboratory data from a study of the Steens fault zone near Denio, Nev. The 200-km-long Steens fault zone forms the longest, most topographically prominent fault-bounded escarpment in the Basin and Range of southern Oregon and northern Nevada. The down-to-the-east normal fault is marked by Holocene fault scarps along nearly half its length, including the southern one-third of the fault from the vicinity of Pueblo Mountain in southern Oregon to the southern margin of Bog Hot Valley (BHV) southwest of Denio, Nev. We studied this section of the fault to better constrain late Quaternary slip rates, which we hope to compare to deformation rates derived from a recently established geodetic network in the region (Hammond and Thatcher, 2005). We excavated a trench in May 2003 across one of a series of right-stepping fault scarps that extend south from the southern end of the Pueblo Mountains and traverse the floor of Bog Hot Valley, about 4 km south of Nevada State Highway 140. This site was chosen because of the presence of well-preserved fault scarps, their development on lacustrine deposits thought to be suitable for luminescence dating, and the proximity of two geodetic stations that straddle the fault zone. We excavated a second trench in the southern BHV, but the fault zone in this trench collapsed during excavation and thus no information about fault history was documented from this site. We also excavated a soil pit on a lacustrine barrier bar in the southern Pueblo Valley (PV) to better constrain the age of lacustrine deposits exposed in the trench. The purpose of this report is to present photomosaics and trench logs, scarp profiles and slip data, soils data, luminescence and radiocarbon ages, and unit descriptions obtained during this investigation. We do not attempt to use the data presented herein to construct a paleoseismic history of this part of the Steens fault zone; that history will be the subject of a future

  16. [High abundance of planctomycetes in anoxic layers of a Sphagnum peat bog].

    PubMed

    Ivanova, A O; Dedysh, S N

    2006-01-01

    The depth distribution of planctomycete abundance has been examined in six different sites of the Sphagnum peat bog in Bakchar, Tomsk oblast, Russia. In situ hybridization of peat with the fluorescently labeled oligonucleotide probes PLA46 and PLA886, reported to be group-specific for representatives of the phylum Planctomycetes, revealed two distinct population maxima of these bacteria in all of the profiles examined. The first population maximum was detected in the uppermost, oxic layer of the bog profile, while the second maximum was located at a depth of 30 cm below the water table level. The population sizes of planctomycetes in the uppermost layer and at a depth of 30 cm were of the same order of magnitude and comprised 0.5-1.5 x 10(7) and 0.4-0.7 x 10(7) cells per g of wet peat, respectively. Only 25-30% of the total number of planctomycete cells in the anoxic layer could be detected if the probe PLA886, whose target specificity is restricted to taxonomically characterized aerobic planctomycetes of the genera Gemmata, Planctomyces, Pirellula, and Isosphaera, was used alone. Other planctomycete cells in this layer were detected only with the probe PLA46, which possesses a much wider scope. This suggests the affiliation of these organisms with a yet undescribed phylogenetic subgroup within the Planctomycetes.

  17. Mictomys borealis (northern bog lemming) and the Wisconsin paleoecology of the east-central Great Basin

    NASA Astrophysics Data System (ADS)

    Mead, Jim I.; Bell, Christopher J.; Murray, Lyndon K.

    1992-03-01

    Teeth of northern bog lemming, Mictomys borealis, are reported from Cathedral and Smith Creek caves and represent the first Wisconsin remains of the genus from the Great Basin. Specimens from Cathedral Cave, Snake Range, are associated with U-series ages of 24,000 to 15,000 yr B.P. Previous work with pollen and packrat middens, dating to the same age as the Mictomys, indicate that Smith Creek Canyon contained a riparian, locally mesic community, including Picea engelmannii (spruce), Betula sp. (birch), Cercocarpus sp. (mountain mahogany), and Artemisia sp. (sagebrush) among other species. Exposed canyon slopes and the adjacent valley apparently contained a more xeric steppe community including sagebrush and Chenopodiineae species; rocky outcrop permitted Pinus flexilis (limber pine) and P. longaeva (bristlecone pine) to grow adjacent to Lake Bonneville or low in the canyon. The region apparently experienced a dry climate (not necessarily drier than today); however, Smith Creek Canyon was fed by glacial meltwater from Mt. Moriah. The northern bog lemming probably lived only in the riparian community and possibly on the north-facing slope below Cathedral Cave. Few canyons of the Snake Range would have had the unusually mesic conditions found in Smith Creek Canyon.

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

    NASA Astrophysics Data System (ADS)

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

    2010-09-01

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

  19. Heat transport in the Red Lake Bog, Glacial Lake Agassiz Peatlands

    USGS Publications Warehouse

    McKenzie, J.M.; Siegel, D.I.; Rosenberry, D.O.; Glaser, P.H.; Voss, C.I.

    2007-01-01

    We report the results of an investigation on the processes controlling heat transport in peat under a large bog in the Glacial Lake Agassiz Peatlands. For 2 years, starting in July 1998, we recorded temperature at 12 depth intervals from 0 to 400 cm within a vertical peat profile at the crest of the bog at sub-daily intervals. We also recorded air temperature 1 m above the peat surface. We calculate a peat thermal conductivity of 0.5 W m-1 ??C-1 and model vertical heat transport through the peat using the SUTRA model. The model was calibrated to the first year of data, and then evaluated against the second year of collected heat data. The model results suggest that advective pore-water flow is not necessary to transport heat within the peat profile and most of the heat is transferred by thermal conduction alone in these waterlogged soils. In the spring season, a zero-curtain effect controls the transport of heat through shallow depths of the peat. Changes in local climate and the resulting changes in thermal transport still may cause non-linear feedbacks in methane emissions related to the generation of methane deeper within the peat profile as regional temperatures increase. Copyright ?? 2006 John Wiley & Sons, Ltd.

  20. Mapping raised bogs with an iterative one-class classification approach

    NASA Astrophysics Data System (ADS)

    Mack, Benjamin; Roscher, Ribana; Stenzel, Stefanie; Feilhauer, Hannes; Schmidtlein, Sebastian; Waske, Björn

    2016-10-01

    Land use and land cover maps are one of the most commonly used remote sensing products. In many applications the user only requires a map of one particular class of interest, e.g. a specific vegetation type or an invasive species. One-class classifiers are appealing alternatives to common supervised classifiers because they can be trained with labeled training data of the class of interest only. However, training an accurate one-class classification (OCC) model is challenging, particularly when facing a large image, a small class and few training samples. To tackle these problems we propose an iterative OCC approach. The presented approach uses a biased Support Vector Machine as core classifier. In an iterative pre-classification step a large part of the pixels not belonging to the class of interest is classified. The remaining data is classified by a final classifier with a novel model and threshold selection approach. The specific objective of our study is the classification of raised bogs in a study site in southeast Germany, using multi-seasonal RapidEye data and a small number of training sample. Results demonstrate that the iterative OCC outperforms other state of the art one-class classifiers and approaches for model selection. The study highlights the potential of the proposed approach for an efficient and improved mapping of small classes such as raised bogs. Overall the proposed approach constitutes a feasible approach and useful modification of a regular one-class classifier.

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

    SciTech Connect

    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.

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

    PubMed

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

    2015-05-14

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

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

    NASA Astrophysics Data System (ADS)

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

    2015-05-01

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

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

    PubMed

    Villa, Chiara; Lynnerup, Niels

    2012-01-01

    Mummification processes, either artificial or natural, preserve the tissues from postmortem decay, but change them from their original state. In this study we provided the first comprehensive set of Hounsfield Unit (HU) ranges specific for tissues mummified under different environmental conditions (peat bog, cold-dry and hot-dry environment). We also analyzed the impact of different museal preservation techniques on the HU ranges, as e.g. in the Tollund Man and Grauballe Man, two bog bodies from Denmark. The HU results for mummies were compared with HU results from forensic cases, cremated 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 of using our re-defined HU ranges by showing the improved results of 3D visualization from automatic segmentation in an Inca mummy from Mount Llullaillaco.

  5. Zero methane emission bogs: extreme rhizosphere oxygenation by cushion plants in Patagonia.

    PubMed

    Fritz, Christian; Pancotto, Veronica A; Elzenga, Josephus T M; Visser, Eric J W; Grootjans, Ab P; Pol, Arjan; Iturraspe, Rodolfo; Roelofs, Jan G M; Smolders, Alfons J P

    2011-04-01

    • Vascular wetland plants may substantially increase methane emissions by producing root exudates and easily degradable litter, and by providing a low-resistance diffusion pathway via their aerenchyma. However, model studies have indicated that vascular plants can reduce methane emission when soil oxygen demand is exceeded by oxygen released from roots. Here, we tested whether these conditions occur in bogs dominated by cushion plants. • Root-methane interactions were studied by comparing methane emissions, stock and oxygen availability in depth profiles below lawns of either cushion plants or Sphagnum mosses in Patagonia. • Cushion plants, Astelia pumila and Donatia fascicularis, formed extensive root systems up to 120 cm in depth. The cold soil (< 10°C) and highly decomposed peat resulted in low microbial activity and oxygen consumption. In cushion plant lawns, high soil oxygen coincided with high root densities, but methane emissions were absent. In Sphagnum lawns, methane emissions were substantial. High methane concentrations were only found in soils without cushion plant roots. • This first methane study in Patagonian bog vegetation reveals lower emissions than expected. We conclude that cushion plants are capable of reducing methane emission on an ecosystem scale by thorough soil and methane oxidation.

  6. Development of a high resolution modeling tool for prediction of waterflows through complex mires: Example of the Mukhrino bog complex in West Siberian middle Taiga Zone

    NASA Astrophysics Data System (ADS)

    Zarov, Evgeny A.; Schmitz, Oliver; Bleuten, Wladimir

    2015-04-01

    Water flow through peat bogs differ substantially from mineral soil landscapes. Permeability of the peatlayers decrease dramatically with depth within the permanently watersaturated peat layers (Catotelm), whereas the 10-60 cm thick superficial layer (Acrotelm) has a very high conductivity. Water flows predominantly in this acrotelm layer where an open structure of stems of mosses and few plants hardly limit water flow. By omitting this superficial flow infrastructures in many places block the waterflow. Moreover, the different bog types within a complex bog have different hydrological conductivities. Without considering the typical water-flow of bogs the construction of roads and platforms for oil and gas production threatens downhill mire ecosystems by partly drainage. The objective of our study was to develop a modeling tool which can be used to predict quantitatively spatially distributed water-flow of a bog complex. A part of the extensive bog complex "Mukhrino bog complex" located at the left bank of Irtysh river near the West Siberian town Khanty-Mansiysk' was chosen as modeling area. Water discharge from this bog catchment occurs by "waterfalls" at the East margin where a scarp with ca. 8 m elevation difference has been developed by backward erosion into the bog by the Mukhrino river. From field observations it was proven that no discharge of groundwater occurred at the margin of the bog catchment area. We used PCRaster-MODFLOW as modeling environment. The model area size was 3.8 km2, cell size 5 m and the model included 3 Acrotelm layers and 3 Catotelm layers. Thickness of Acrotelm and Catotelm have been measured by coring in transects. Input data of rain, snow have been recorded in the study area. Evapotranspiration was measured with small lysimeters and crop factors for different land unit types (open water, raised bog, patterned bog, poor fens) were elaborated by water balance modeling (1-D). Land unit types have been mapped by supervised classification

  7. A Holocene record of climate, vegetation change and peat bog development, east Otago, South Island, New Zealand

    NASA Astrophysics Data System (ADS)

    McGlone, Matt S.; Wilmshurst, Janet M.

    1999-05-01

    A Holocene record of pollen, macrofossils, testate amoebae and peat humification is presented from a small montane bog. Sediment accumulation began before 9000 yr BP, but peat growth not until ca. 7000 BP. From 12 000 to 7000 yr BP, a shrub-grassland dominated under a dry climate, with increasing conifer forest and tall scrub from ca. 9600 yr BP. At 7000 yr BP a dense montane-subalpine low conifer forest established under a moist, cool climatic regime. Between 7000 and 700 yr BP the bog surface was shrubby, tending to be dry but with highly variable surface wetness. The catchment was affected by major fire at least four times between 4000 and 1000 yr BP. Both fire and bog surface wetness may have been linked to ENSO-caused variations in rainfall. Cooler, cloudier winters and disturbance by fire promoted the expansion of the broadleaf tree Nothofagus menziesii between 4000 yr BP and 1300 yr BP at the expense of the previous conifer forest-scrub vegetation. Polynesian fires (ca. 700 yr BP) reduced the vegetation to tussock grassland and bracken. Deforestation did not markedly affect the hydrology of the site. European pastoralism since ad 1860 has increased run-off and rising water tables in the bog have led to a Sphagnum-dominated cover.

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

    PubMed

    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 <1 to 18.3 % of the total bacteria. The vertical distribution of AAPs confirmed their presence in the upper parts of the 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.

  9. Draft Genome Sequence of Chromobacterium subtsugae MWU12-2387 Isolated from a Wild Cranberry Bog in Truro, Massachusetts

    PubMed Central

    Vöing, Kristin; Harrison, Alisha

    2017-01-01

    ABSTRACT Chromobacterium subtsugae MWU12-2387 was isolated from the rhizosphere of cranberry plants. While it is unknown what environmental role these bacteria play in bog soils, they hold potential as biological control agents against nematodes and insect pests. Potential virulence genes were identified, including the violacein synthesis pathway, siderophores, and several chitinases. PMID:28336605

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

    PubMed

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

    2016-11-01

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

  11. Draft Genome Sequence of Chromobacterium subtsugae MWU12-2387 Isolated from a Wild Cranberry Bog in Truro, Massachusetts.

    PubMed

    Vöing, Kristin; Harrison, Alisha; Soby, Scott D

    2017-03-23

    Chromobacterium subtsugae MWU12-2387 was isolated from the rhizosphere of cranberry plants. While it is unknown what environmental role these bacteria play in bog soils, they hold potential as biological control agents against nematodes and insect pests. Potential virulence genes were identified, including the violacein synthesis pathway, siderophores, and several chitinases.

  12. Geology and recognition criteria for sandstone uranium deposits in mixed fluvial-shallow marine sedimentary sequences, South Texas. Final report

    SciTech Connect

    Adams, S.S.; Smith, R.B.

    1981-01-01

    Uranium deposits in the South Texas Uranium Region are classical roll-type deposits that formed at the margin of tongues of altered sandstone by the encroachment of oxidizing, uraniferous solutions into reduced aquifers containing pyrite and, in a few cases, carbonaceous plant material. Many of the uranium deposits in South Texas are dissimilar from the roll fronts of the Wyoming basins. The host sands for many of the deposits contain essentially no carbonaceous plant material, only abundant disseminated pyrite. Many of the deposits do not occur at the margin of altered (ferric oxide-bearing) sandstone tongues but rather occur entirely within reduced, pyurite-bearing sandstone. The abundance of pyrite within the sands probably reflects the introduction of H/sub 2/S up along faults from hydrocarbon accumulations at depth. Such introductions before ore formation prepared the sands for roll-front development, whereas post-ore introductions produced re-reduction of portions of the altered tongue, leaving the deposit suspended in reduced sandstone. Evidence from three deposits suggests that ore formation was not accompanied by the introduction of significant amounts of H/sub 2/S.

  13. Ecophysiological mechanisms characterising fen and bog species: focus on variations in nitrogen uptake traits under different soil-water pH.

    PubMed

    Nakamura, Takatoshi; Nakamura, Motoka

    2012-04-01

    Although the productivity and nitrogen (N)-use traits of mire plants differ dramatically between fens and bogs, soil N richness does not necessarily differ, whereas the soil-water pH is distinctly lower in bogs than in fens. The ecophysiological mechanisms underlying these relations are unclear. To assess the relative availability of N forms in relation to soil-water pH, we focused on the net N uptake rate per unit root weight (NNUR), glutamine synthetase activity and nitrate reductase activity, and performed reciprocal transplant experiments with the seedlings of fen (Carex lyngbyei) and bog (C. middendorffii) sedge species in intact habitat sites. The soil-water pH was clearly lower at the bog site, but the NH(4) (+), NO(3) (-) or dissolved organic-N concentrations did not differ between the fen and bog sites. The activity of both enzymes for inorganic-N assimilation did not differ among the sites and species. However, the fen species grown at bog sites showed a drastic decrease in the NNUR, suggesting a suppression of organic-N uptake. The bog species showed no NNUR difference between the sites. These results indicate that inorganic-N availability does not differ between the two habitats, but organic-N availability is lowered in a low-pH bog, particularly in the case of fen species. Therefore, the relative availability of N forms shows species-specific variations that depend on the differences in the soil-water pH of root zone, even at similar N richness, which would play a key role in plant distribution strategies in relation to the fen-bog gradient.

  14. Purple Pitcher Plant (Sarracenia rosea) Dieback and Partial Community Disassembly following Experimental Storm Surge in a Coastal Pitcher Plant Bog

    PubMed Central

    Abbott, Matthew J.; Battaglia, Loretta L.

    2015-01-01

    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. PMID:25874369

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

    PubMed

    Abbott, Matthew J; Battaglia, Loretta L

    2015-01-01

    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.

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

    PubMed

    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.

  17. Modeling regional groundwater flow in a peat bog complex in Ontario, Canada

    NASA Astrophysics Data System (ADS)

    Durejka, Stefan; Knorr, KLaus-Holger; Blodau, Christian; Frei, Sven

    2013-04-01

    Peatlands are important ecohydrological systems and contribute significantly to the global carbon cycle. They function as carbon sinks through CO2-sequestration but also emit methane depending i.a. on the prevailing hydrological structures. Knowledge of their hydrology including exchange between the groundwater and surface water domain is thus necessary to understand wetland environments and to determine their vulnerability to climate changes. The impact of proposed wetter conditions on wetland hydrological homeostastis in northern bogs is uncertain to this date. Elevated water tables due to changing hydrological flow patterns may affect the characteristics of wetlands as a carbon reservoir. Modeling approaches allow quantifying and qualifying of these flow patterns on a longer time scale. Luther Bog is located in Southern Ontario. The ombotrophic bog to poor fen is partially bordered by Luther Lake which inundates the area since its creation in 1952. In this study the interaction between the wetland and the adjacent lake is modeled using the fully-integrated HydroGeoSphere model. A transient three-dimensional groundwater mode is set up for a small catchment with the lake level implemented as a constant-head boundary condition. Hydraulic properties of the peat were estimated executing bail tests on multilevel piezometers at different sites within the wetland. The first hypothesis is that the wet conditions in the runoff network keep the water table in the wetland high over a specific transition zone. The Second is that there may be a reversal of flow directions over the hydrological year, due to varying boundary conditions, e.g. evapotranspiration and precipitation. First results indicate that exchange rates may be very slow. This is supported by manual measurements of little hydraulic gradients and little topographic gradients. The results also show a seasonal effect in flow directions in both, the groundwater and the surface water domain. The model will be tested

  18. The role of common upland vegetation on gaseous carbon cycling on UK blanket peat bogs

    NASA Astrophysics Data System (ADS)

    Dixon, Simon; Rowson, James; Worrall, Fred

    2010-05-01

    The most important control upon the carbon dynamics of any peatland is vegetation. However there is a gap in the literature with respect to comparative, in-situ studies of common upland vegetation types on peat bogs from a carbon cycling perspective. Where studies exist they tend to be narrowly focused (i.e. on one or two species or a small geographical area) or are laboratory manipulation studies. This study set out to compare gaseous CO2 exchange, in situ, across a broad (geographic) range of sites dominated by differing, common, upland vegetation types. The vegetation types studied were; Calluna vulgaris, Sphagnum spp., Eriophorum (E. angustifolium + E. vaginatum), Molinia caerulea and areas revegetated with a lawn grass mixture that was used for restoration (Festuca spp, Deschampsia spp. and Agrostis spp.).The primary aim of the study was to assess the carbon cycling potential of the common upland vegetation types, in order to produce clearer evidence as to which upland species produce the most efficient carbon sinks. The study was carried out in the South Pennines and Peak District of England. All readings were taken from upland-blanket peat bogs, as this type of bog accounts for 87% of the UK's peatlands, and therefore the results of this study can have the widest possible applicability to the rest of the UK's peat reserves. NEE and NER measurements were taken with a PP Systems EMG-4 infra-red gas analyzer. PAR and air temperature readings were taken along side water table and soil pore water samples from every site. Each site was visited monthly for at least 12 months and between 3-9 replicates were recorded per site. The results of this study will deal with the effects vegetation has on NER, GPP and NEE, focusing on which vegetation types make the most efficient gaseous carbon sinks. Moreover the effect of vegetation on water table levels and water quality will be discussed. Finally a consideration of how the age of Calluna vulgaris affects the parameters

  19. Soil data for a thermokarst bog and the surrounding permafrost plateau forest, located at Bonanza Creek Long Term Ecological Research Site, Interior Alaska

    USGS Publications Warehouse

    Manies, Kristen L.; Fuller, Christopher C.; Jones, Miriam C.; Waldrop, Mark P.; McGeehin, John P.

    2017-01-19

    Peatlands play an important role in boreal ecosystems, storing a large amount of soil organic carbon. In northern ecosystems, collapse-scar bogs (also known as thermokarst bogs) often form as the result of ground subsidence following permafrost thaw. To examine how ecosystem carbon balance changes with the loss of permafrost, we measured carbon and nitrogen storage within a thermokarst bog and the surrounding forest, which continues to have permafrost. These sites are a part of the Bonanza Creek Long Term Ecological Research (LTER) site and are located within Interior Alaska. Here, we report on methods used for core collection analysis as well as the cores’ physical, chemical, and descriptive properties.

  20. How suitable are peat cores to study historical deposition of PAHs?

    PubMed

    Thuens, Sabine; Blodau, Christian; Radke, Michael

    2013-04-15

    Ombrotrophic peat bogs are natural archives of atmospheric pollution, their depth profiles can be used to study the deposition chronology of harmful contaminants. Prerequisites for deriving historical deposition rates from the peat archive are that contaminants are persistent and immobile in the peat and that the applied dating technique is accurate. To examine these requirements and the accuracy of peat archives for polycyclic aromatic hydrocarbons (PAHs) 12 peat profiles were sampled in 4 bogs in Ontario, Canada, as well as surface peat in one bog. Additionally we carried out laboratory incubations; no degradation occurred over a 3-year period in these experiments. The standard deviations of PAH concentrations in surface samples and of PAH inventories in whole cores was approximately 30%, and concentrations in surface peat were on average 50% higher in hollows than in hummocks. No indications for mobility of PAHs were observed in peat. Temporal deposition trends inferred from peat cores were generally in agreement with trends derived from a sediment core sampled close by but deposition rates to the sediment were substantially higher. A major source of uncertainty was the rather coarse vertical sampling resolution of 5 cm which introduced substantial uncertainty in the dating of the individual segments. This caused variations of the deposition rates up to 70% per PAH between three replicate cores, and it also impedes the identification of deposition peaks. Overall, we conclude that peat cores are suitable archives for inferring atmospheric deposition trends, but due to their relatively low temporal resolution short-term events may not be identified and the development of sampling methods that allow a higher vertical resolution would greatly improve the performance of the method. The analysis of more than one core per site is suggested to provide a realistic estimate of the historic deposition and total inventories.

  1. A new species of mermithid (Nematoda) in chironomids eclosing from a northern Minnesota bog.

    PubMed

    Johnson, Arthur A; Kleve, Maurice G

    2008-12-01

    Hydromermis haggardi n. sp. (Nematoda: Mermithidae) is described from the hemocoel of chironomid imagos eclosing from Lake Alice Bog in northern Minnesota in June and July 2007. The species is distinguished from the other 27 described members of the genus by the subventral mouth, tulip shape to anterior end of esophagus, colorless vesicular trophosome, single nonbifurcated spicule, short body lengths of both males and females, structure of the S-shaped vagina, decrease in body width at vulva, brevity of postparasitic stage, and the greater development of a posterior ventral protractor muscle in the males. An anomalous adult male bearing large oval structures in the posterior testis is reported. Evidence is presented for the developmental interaction of the new species with Lanceimermis palustris Johnson and Kleve, 2004.

  2. Climate-growth relationships for bog-grown black spruce in northern Minnesota

    SciTech Connect

    Vogel, K.J. )

    1993-06-01

    Black spruce (Picea mariana) tree-ring chronologies were derived for three bogs in northern Minnesota. Standard chronologies were highly intercorrelated (0.72 to 0.87). The ring-width variability attributable to a common signal ranged from 38.6 to 56.8 percent which is large for closed canopy eastern forests. These chronologies exhibited great serial correlation, therefore all chronologies were autoregressively modelled prior to climatic analyses. Each chronology was compared to monthly temperature and precipitation data from a nearby weather station. Strengths of linear relationships were measured by the product-moment correlation coefficient. May and August temperatures from the previous year and March precipitation of the current year were significantly correlated with ring-width indices. These data suggest that tree-ring chronologies from mid-continental peatlands may be a valuable, though presently ignored, source of paleoclimatic data.

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

    PubMed

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

    2015-01-01

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

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

    SciTech Connect

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

    1982-10-01

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

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

    NASA Astrophysics Data System (ADS)

    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. Insights into functional bacterial diversity and its effects on Alpine bog ecosystem functioning.

    PubMed

    Bragina, Anastasia; Berg, Christian; Müller, Henry; Moser, Daniel; Berg, Gabriele

    2013-01-01

    Plant-associated bacteria are important for the growth and health of their host, but little is known about its functional diversity and impact on ecosystem functioning. We studied bacterial nitrogen fixation and methane oxidation from indicator Sphagnum mosses in Alpine bogs to test a hypothesis that the plant microbiome contained different functional patterns depending on their functions within the ecosystem. A high abundance and diversity of nitrogenase genes were detected, mostly specific for each Sphagnum. In contrast, methanotrophs formed highly similar patterns despite a high abundance and diversity of methane monooxygenase genes. Our hypothesis was supported by these contrasting functional patterns together with the result that the Sphagnum sporophyte contained a high proportion of specific diazotrophs (45.5%) but no potential methanotrophs. While essential for plant growth under nutrient-limited conditions, nitrogen-fixing bacteria were highly specific and transferred with the sporophyte unlike the ubiquitous methanotrophs which are important for the climate-relevant ecosystem itself.

  7. Effect of selected metal ions on the photocatalytic degradation of bog lake water natural organic matter.

    PubMed

    Espinoza, Luis A Tercero; ter Haseborg, Eike; Weber, Matthias; Karle, Elly; Peschke, Rafael; Frimmel, Fritz H

    2011-01-01

    Herein we report the photocatalytic degradation of natural organic matter from a bog lake (Lake Hohloh, Black Forest, Germany) in the presence of 0, 5, and 10 μmol L(-1) of added Cu(2+), Mn(2+), Zn(2+) and Fe(3+). The reactions were followed by size exclusion chromatography with organic carbon detection (SEC-DOC) and by measurements of low molecular weight organic acids. Addition of Cu(2+) had the largest effect of all four studied metals, leading to a retardation in the molecular size changes in NOM: degradation of the larger molecular weight fraction was inhibited leading to reduced production of smaller molecular weight metabolites. Similarly, addition of Cu(2+) reduced the production of formic and oxalic acids, and reduced the bioavailability of the partially degraded NOM.

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

    NASA Astrophysics Data System (ADS)

    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.

  9. The Lipid Biomarker Holocene Paleoclimate Record of West China in the Zoige-Hongyuan Peat Deposit

    NASA Astrophysics Data System (ADS)

    Zhou, W.; Zheng, Y.; Meyers, P.; Xie, S.

    2006-12-01

    Paleoclimate reconstructions based on lipid biomarkers from peat bogs are relatively uncommon, although this approach has been widely applied to lake sediments where it yields histories of climate-related changes in types of vegetation and organic matter preservation. We describe stratigraphic patterns in peat lipid biomarker distributions extracted from a well-dated peat core from the Zoige-Hongyuan peat bog. The bog is on the Qinghai-Xizang Plateau of west China on the northeast edge of the Tibetan Plateau and has accumulated a continuous deposit of peat during the latest Pleistocene and the Holocene. A period of warmer climate corresponding to the Holocene Optimum between 9 ka to 5 ka is evident in greater alterations of n-alkanoic acids and n-alkanols and in the appearance of biomarkers diagnostic of greater microbial activity. Changes in local precipitation that modified the water level of the peat bog are indicated by increases in the proportions of C23 and C25 n-alkanes that are mainly derived from submerged/floating plants. Alternations in submergent and emergent plant n-alkane proxies reveal millennial scale rises and falls of the bog water level in the Tibetan Plateau, thereby reflecting variations in Asian monsoon precipitation during the Holocene. Major low water level events occurred around 12.6, 11.3, 10.7, 9.4, 8.3, 6.0, 4.5, 3.1, 2.1, and 1.0 ka. These events correlate well with cold-dry events recorded in same region by other climatic proxies. These results reflect Holocene instability in the Asian monsoon system. Our results indicate that millennial-scale variability in precipitation is more sensitive than temperature in reflecting Asian monsoon climatic dynamics on the Tibetan Plateau.

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

    PubMed

    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

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

    NASA Astrophysics Data System (ADS)

    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

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

    NASA Astrophysics Data System (ADS)

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

    2015-02-01

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

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

    SciTech Connect

    Alm, J.; Silvola, J.; Schulman, L.; Walden, J.; Nykaenen, H.; Martikainen, P.J.

    1999-01-01

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

  14. Nutrient resorption of two evergreen shrubs in response to long‑term fertilization in a bog.

    PubMed

    Wang, Meng; Murphy, Meaghan T; Moore, Tim R

    2014-02-01

    Plant resorption of multiple nutrients during leaf senescence has been established but stoichiometric changes among N, P and K during resorption and after fertilization are poorly understood. We anticipated that increased N supply would lead to further P limitation or co-limitation with N or K [i.e. P-(co)limitation], decrease N resorption and increase P and K resorption, while P and K addition would decrease P and K resorption and increase N resorption. Furthermore, Ca would accumulate while Mg would be resorbed during leaf senescence, irrespective of fertilization. We investigated the effect of N, P and K addition on resorption in two evergreen shrubs (Chamaedaphne calyculata and Rhododendron groenlandicum) in a long-term fertilization experiment at Mer Bleue bog, Ontario, Canada. In general, N addition caused further P-(co)limitation, increased P and K resorption efficiency but did not affect N resorption. P and K addition did not shift the system to N limitation and affect K resorption, but reduced P resorption proficiency. C. calyculata resorbed both Ca and Mg while R. groenlandicum resorbed neither. C. calyculata showed a higher resorption than R. groenlandicum, suggesting it is better adapted to nutrient deficiency than R. groenlandicum. Resorption during leaf senescence decreased N:P, N:K and K:P ratios. The limited response of N and K and the response of P resorption to fertilization reflect the stoichiometric coupling of nutrient cycling, which varies among the two shrub species; changes in species composition may affect nutrient cycling in bogs.

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

    PubMed

    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.

  16. Reconnaissance for radioactive deposits in eastern Alaska, 1952

    USGS Publications Warehouse

    Nelson, Arthur Edward; West, Walter S.; Matzko, John J.

    1954-01-01

    Reconnaissance for radioactive deposits was conducted in selected areas of eastern Alaska during 1952. Examination of copper, silver, and molybdenum occurrences and of a reported nickel prospect in the Slana-Nabesna and Chisana districts in the eastern Alaska Range revealed a maximum radioactivity of about 0.003 percent equivalent uranium. No appreciable radioactivity anomolies were indicated by aerial and foot traverses in the area. Reconnaissance for possible lode concentrations of uranium minerals in the vicinity of reported fluoride occurrences in the Hope Creek and Miller House-Circle Hot Springs areas of the Circle quadrangle and in the Fortymile district found a maximum of 0.055 percent equivalent uranium in a float fragment of ferruginous breccia in the Hope Creek area; analysis of samples obtained in the vicinity of the other fluoride occurrences showed a maximum of only 0.005 percent equivalent uranium. No uraniferous loads were discovered in the Koyukuk-Chandalar region, nor was the source of the monazite, previously reported in the placer concentrates from the Chandalar mining district, located. The source of the uranotheorianite in the placers at Gold Bench on the South Fork of the Koyukuk River was not found during a brief reconaissance, but a placer concentrate was obtained that contains 0.18 percent equivalent uranium. This concentrate is about ten times more radioactive than concentrates previously available from the area.

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

    NASA Astrophysics Data System (ADS)

    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.

  18. CO2 fluxes at northern fens and bogs have opposite responses to inter-annual fluctuations in water table

    NASA Astrophysics Data System (ADS)

    Sulman, Benjamin N.; Desai, Ankur R.; Saliendra, Nicanor Z.; Lafleur, Peter M.; Flanagan, Lawrence B.; Sonnentag, Oliver; Mackay, D. Scott; Barr, Alan G.; van der Kamp, Garth

    2010-10-01

    This study compares eddy-covariance measurements of carbon dioxide fluxes at six northern temperate and boreal peatland sites in Canada and the northern United States of America, representing both bogs and fens. The two peatland types had opposite responses of gross ecosystem photosynthesis (GEP) and ecosystem respiration (ER) to inter-annual fluctuations in water table level. At fens, wetter conditions were correlated with lower GEP and ER, while at bogs wetter conditions were correlated with higher GEP and ER. We hypothesize that these contrasting responses are due to differences in the relative contributions of vascular plants and mosses. The coherence of our results between sites representing a range of average environmental conditions indicates ecosystem-scale differences in resilience to hydrological changes that should be taken into account when considering the future of peatland ecosystem services such as carbon sequestration under changing environmental conditions.

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

    NASA Astrophysics Data System (ADS)

    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.

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

    NASA Astrophysics Data System (ADS)

    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.

  1. Metallogeny, structural, lithological and time controls of ore deposition in anoxic environments

    NASA Astrophysics Data System (ADS)

    Kříbek, B.

    1991-04-01

    Accumulation of metals in anoxic environments occurs by sorption and precipitation from seawater, fossil brines or hydrothermal solutions. Metals can be remobilized during subsequent metamorphic and magmatic processes and form ore deposits. This type of mineralization is governed chiefly by the type of tectonic setting of the anoxic environment. Carbonaceous sediments of passive margins contain only subeconomic concentrations of uranium, vanadium and molybdenum. Cubearing black shales and the submarine-exhalative type of mineralization are confined to the environments of continental rifts and aulacogens or to back-arc basins of active margins. Metamorphogenic deposits are mainly connected with collision margins but they may also occur in other types of tectonic environments. The formation of Cu-bearing black shales was controlled by period of low sea-level during the break-up of supercontinents in the Earth's evolution. Increased contents of uranium and vanadium accumulated in black shales in periods of sealevel highstands. Lithological control is apparent in deposits of Cu-bearing and uraniferous black shales. On the contrary, the occurrence of polymetallic mineralization does not depend on the lithological maturity of carbonaceous sediments.

  2. Sphagnum N and P Stoichiometry Indicates P-limitation on N2 Fixation in Ombrotrophic Bogs

    NASA Astrophysics Data System (ADS)

    Zivkovic, T.; Moore, T. R.; Disney, K.

    2015-12-01

    Biological N2 fixation is an important N input in ombrotrophic, nutrient poor and Sphagnum dominated bogs. As an energetically costly process, by which each N2 molecule is fixed to a cost of 16ATP molecules, N2 fixation might be P limited process. In this study we tested whether moss P and N concentrations, and N:P ratios could explain N2 fixation in the top 6cm photosynthetically active Sphagnum moss across eight ombrotrophic bogs along south-north geographical gradient in Ontario and Quebec. Under constant environmental conditions, we incubated subsamples of the surface Sphagnum mosses by using both, acetylene reduction assays (ARA) and 15N2 enriched method to measure N2 fixation rates. Same subsamples were later analyzed for N and P concentrations. Our preliminary data show that the increase of P concentration within moss capitula is related to a significant linear increase of ARA rates (R2=0.18, p<0.0001, N=150). N:P ratios showed a significant negative linear relationship with ARA (R2=0.34, p<0.0001, N=150) indicating that P limitation in the photosynthetically active part of mosses in bogs may also indicate P limitation on microbial N2 fixation

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

    NASA Astrophysics Data System (ADS)

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

    2015-02-01

    Northern peatlands hold large amounts of organic carbon (C) in their soils and are as such important in a climate change context. Blanket bogs, i.e. nutrient-poor peatlands restricted to maritime climates, may be extra vulnerable to global warming since they require a positive water balance to sustain their moss dominated vegetation and C sink functioning. This study presents a 4.5 year record of land-atmosphere carbon dioxide (CO2) exchange from the Andøya blanket bog in northern Norway. Compared with other peatlands, the Andøya peatland exhibited low flux rates, related to the low productivity of the dominating moss and lichen communities and the maritime settings that attenuated seasonal temperature variations. It was observed that under periods of high vapour pressure deficit, net ecosystem exchange was reduced, which was mainly caused by a decrease in gross primary production. However, no persistent effects of dry conditions on the CO2 exchange dynamics were observed, indicating that under present conditions and within the range of observed meteorological conditions the Andøya blanket bog retained its C uptake function. Continued monitoring of these ecosystem types is essential in order to detect possible effects of a changing climate.

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

    PubMed

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

    2015-09-01

    (79)Se is among the most important long lived radionuclides in spent nuclear fuel and selenite, SeO3(2-), is its typical form in intermediate redox potential. The sorption behaviour of selenite and the bacterial impact on the selenite sorption in a 7-m-deep profile of a nutrient-poor boreal bog was studied using batch sorption experiments. The batch distribution coefficient (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.

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

    PubMed

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

    2016-10-25

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

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

    NASA Astrophysics Data System (ADS)

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

    2015-07-01

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

  7. Effects of Nutrient Addition on Belowground Stoichiometry and Microbial Activity in an Ombrotrophic Bog

    NASA Astrophysics Data System (ADS)

    Pinsonneault, A. J.; Moore, T. R.; Roulet, N. T.

    2015-12-01

    Ombrotrophic bogs are both nutrient-poor systems and important carbon (C) sinks yet there remains a dearth of information on the stoichiometry of C, nitrogen (N), phosphorus (P), and potassium (K), an important determinant of substrate quality for microorganisms, in these systems. In this study, we quantified the C, N, P, and K concentrations and stoichiometric ratios of both soil organic matter (SOM) and dissolved organic matter (DOM) as well as microbial extracellular enzyme activity from 0 - 10cm depth in a long-term fertilization experiment at Mer Bleue bog, Ontario, Canada. Though trends in C:N, C:P, and C:K between SOM and DOM seem to follow one another, preliminary results indicate that the stoichiometric ratios of DOM were at least an order of magnitude smaller than those of DOM suggesting that nutrient fertilization impacts the quality of DOM as a microbial substrate to a greater degree than SOM. C:N decreased with greater nitrogen addition but C:P and C:K increased; the magnitude of that increase being smaller in NPK treatments relative to N-only treatments suggesting co-limitation by P and/or K. This is further supported by the increase in activity of both the C-cycling enzyme, β-D-glucosidase (bdG), and the P-cycling enzyme, phosphatase (Phos), with greater nitrogen addition; particularly in NPK-treatments for bdG and N-only treatments for Phos. The activity of the N-cycling enzyme, N-acetyl-β-D-glucosaminidase, and the C-cycling enzyme, phenol oxidase, with greater N-addition suggests a decreased need to breakdown organic nitrogen to meet microbial N-requirements in the former and N-inhibition in the latter consistent with findings in the literature. Taken together, these results suggest that higher levels of nutrients impact both microbial substrate quality as well as the activity of microbial enzymes that are key in the decomposition process which may ultimately decrease the ability of peatlands to sequester carbon.

  8. Linking glacial deposits and lake sediments for paleoclimate studies in the Northern Romanian Carpathians

    NASA Astrophysics Data System (ADS)

    Zamosteanu, Andrei; Mindrescu, Marcel; Anselmetti, Flavio; Akçar, Naki; Lowick, Sally E.; Vogel, Hendrik

    2015-04-01

    Timing and extent of glaciations in the Carpathian mountains are still controversely discussed, mostly due to the lack of well dated geomorphological and geochronological studies. We present the preliminary results of geomorphological and sedimentological analyses of glacial and lacustrine deposits in Bistricioara Valley located in the Rodna Mountains (Northern Romanian Carpathians). Most of the glacial deposits in the Romanian Carpathians, such as moraines, typically occur above 1600 m a.s.l. marking the maximum lowering of past glaciations. Most of the glacial lakes occur between 1800 and 2000 m a.s.l. Field surveys included mapping of moraines and erratic boulders using detailed topographical maps and aerial photos. A Digital Elevation Model (DEM) was derived using GIS (ArcMap 10.1) from 1:25000 topographic maps, which was further completed by field survey data. The resulting geomorphological map shows a series of moraines, which indicate the occurrence of several glacial phases in the study area. Sediment samples were collected from a peat bog (1630 m a.s.l.) dammed by a large lateral moraine within Bistricioara Mare, one of the largest glacial cirques in the Romanian Carpathians. A Russian corer was used to extract the sediment profile from the peat bog (approx. 5 m long sediment core). A X-ray computed tomography (CT) system was employed for the study of sedimentary and deformation structures and X-ray fluorescence spectroscopy (XRF) for multi-element analysis at high resolution. Glacial deposits from the lateral moraine in front of the peat bog were also sampled, as well as from the frontal moraines, upstream and downstream of the peat bog. This set of samples from multiple archives allows to link and merge the chronologies and the paleoenvironmental records of glacial deposits and lake sediments. Moreover, we employed cosmogenic nuclide dating for the reconstruction of glacial stages and their paleoclimatic implications during deglaciation in this area of

  9. Characterization of Groundwater Flow Processes in the Cedar Creek Watershed and the Cedarburg Bog in Southeastern Wisconsin

    NASA Astrophysics Data System (ADS)

    Graham, J. P.; Han, W. S.; Feinstein, D.; Hart, D. J.

    2014-12-01

    The purpose of this study is to characterize the geology and groundwater flow of the bog as well as the surrounding area, notably the Cedar Creek Watershed, a HUC (Hydrologic Unit Code) 12 watershed. The watershed is approximately 330 km2, and borders the sub-continental divide separating the Mississippi River Basin from the Great Lakes Basin. The Cedar Creek watershed is composed of mostly agricultural and urban land with a significant stress of groundwater withdrawal for both irrigation and residential use. This watershed has importance due to the contribution to both the Milwaukee River and Lake Michigan, and is integral in the study of regional groundwater flow of Southeastern Wisconsin. Furthermore, the Cedarburg Bog, located in the northeast corner of the Cedar Creek Watershed preserves diverse ecology and is recognized by the U.S. Department of Interior as a National Landmark. Groundwater is the primary driver for the diverse and unique ecology that is contained within the bog. Within the Cedar Creek Watershed, well data and glacial geology maps (Mickelson and Syverson, 1997) were integrated to develop a 3-dimensional subsurface map and watershed-scale groundwater flow model using the LAK3 and the SFR2 package to simulate surface water-aquifer interactions. The model includes 10 zones of the glacial sediments and the weathered and consolidated Silurian Dolomite bedrock. The hydraulic conductivity and storage parameters were calibrated with 203 head targets using universal parameter estimation code (PEST). Then, a series of future climate scenarios, developed by the Wisconsin Initiative on Climate Change Impact, were implemented to the USGS Soil-Water-Balance Code (SWB) to identify variations in recharge. The simulated recharge scenarios were adopted to predict the response of groundwater resources in the watershed and the Cedarburg Bog. Preliminary results produced from the MODFLOW model indicate the bog is acting as a recharge zone under current recharge

  10. Fine-scale horizontal and vertical micro-distribution patterns of testate amoebae along a narrow Fen/Bog gradient.

    PubMed

    Jassey, Vincent E J; Chiapusio, Geneviève; Mitchell, Edward A D; Binet, Philippe; Toussaint, Marie-Laure; Gilbert, Daniel

    2011-02-01

    The ecology of peatland testate amoebae is well studied along broad gradient from very wet (pool) to dry (hummock) micro-sites where testate amoebae are often found to respond primarily to the depth to water table (DWT). Much less is known on their responses to finer-scale gradients, and nothing is known of their possible response to phenolic compounds, which play a key role in carbon storage in peatlands. We studied the vertical (0-3, 3-6, and 6-9 cm sampling depths) micro-distribution patterns of testate amoebae in the same microhabitat (Sphagnum fallax lawn) along a narrow ecological gradient between a poor fen with an almost flat and homogeneous Sphagnum carpet (fen) and a "young bog" (bog) with more marked micro-topography and mosaic of poor fen and bog vegetation. We analyzed the relationships between the testate amoeba data and three sets of variables (1) "chemical" (pH, Eh potential, and conductivity), (2) "physical" (water temperature, altitude, i.e., Sphagnum mat micro-topography, and DWT), and (3) phenolic compounds in/from Sphagnum (water-soluble and primarily bound phenolics) as well as the habitat (fen/bog) and the sampling depth. Testate amoeba Shannon H' diversity, equitability J of communities, and total density peaked in lower parts of Sphagnum, but the patterns differed between the fen and bog micro-sites. Redundancy analyses revealed that testate amoeba communities differed significantly in relation to Eh, conductivity, water temperature, altitude, water-soluble phenolics, habitat, and sampling depth, but not to DWT, pH, or primarily bound phenolics. The sensitivity of testate amoebae to weak environmental gradients makes them particularly good integrators of micro-environmental variations and has implications for their use in paleoecology and environmental monitoring. The correlation between testate amoeba communities and the concentration of water-soluble phenolic suggests direct (e.g., physiological) and/or indirect (e.g., through impact on

  11. Reconnaissance of uranium and copper deposits in parts of New Mexico, Colorado, Utah, Idaho, and Wyoming

    USGS Publications Warehouse

    Gott, Garland B.; Erickson, Ralph L.

    1952-01-01

    Because of the common association of uranium and copper in several of the commercial uranium deposits in the Colorado Plateau Province, a reconnaissance was made of several known deposits of copper disseminated through sandstone to determine whether they might be a source of uranium. In order to obtain more information regarding the relationship between copper, uranium and carbonaceous materials, some of the uraniferious asphaltrite deposits in the Shinarump conglomerate along the west flank of the San Rafael Swell were also investigated briefly. During this reconnaissance 18 deposits were examined in New Mexico, eight in Utah, two in Idaho, and one each in Wyoming and Colorado. No uranium deposits of commercial grade are associated with the copper deposits that were examined. The uraniferous asphaltites in the Shinarump conglomerate of Triassic age on the west flank of the San Rafael Swell, however, are promising from the standpoint of commercial uranium production. Spectrographic analyses of crude oil, asphalt, and bituminous shales show a rather consistent suite of trace metals including vanadium, nickel, copper, cobalt, chromium, lead zinc, and molybdenum. The similarity of the metal assemblage, including uranium of the San Rafael Swell asphaltites, to the metal assemblage in crude oil and other bituminous materials suggests that these metals were concentrated in the asphaltites from petroleum. However, the hypothesis that uranium minerals were already present before the hydrocarbons were introduced and that some sort of replacement or uranium minerals by carbon compounds was effected after the petroleum migrated into the uranium deposit should not be disregarded. The widespread association of uranium with asphaltic material suggests that it also may have been concentrated by some agency connected with the formation of petroleum. The problem of the association of uranium and other trace metals with hydrocarbons should be studied further both in the field and in

  12. Heuristic numerical and analytical models of the hydrologic controls over vertical solute transport in a domed peat bog, Jura Mountains, Switzerland

    NASA Astrophysics Data System (ADS)

    McKenzie, Jeffrey M.; Siegel, Donald I.; Shotyk, William; Steinmann, Philipp; Pfunder, Gabriele

    2002-04-01

    We report the results of numerical and analytical simulations to test the hypothesis that downward vertical flow of porewater from the crests of domed alpine and kettle bogs controls vertical porewater distributions of major solutes such as Ca and Mg. The domed Etang de la Gruère bog (EGr), Switzerland, characterized by a vertical downward gradient of 0·04 and stratified layers of peat, is chosen as a field site for the model calibration and evaluation. The middle 4-m section of the 6·5 m thick bog peat is heavily humified and has a hydraulic conductivity of 10-5·6 cm s-1. Above and below, peat is less humified with a hydraulic conductivity of 10-3 cm s-1. Heuristic finite difference simulations, using Visual MODFLOW, of the bog hydraulics show that the higher conductivity peat at the bog base is critical to create the observed deep, local flow cells that substantively recharge porewater.Model results and Peclet number calculations show that before 7000 14C yr BP diffusion of solutes from underlying mineral soils controlled the vertical distribution of porewater chemistry. From 7000 to 1250 14C BP the porewater chemistry was probably controlled by both upward diffusion and downward advection, and after 1250 14C yr BP porewater chemistry was probably controlled by downward advection. Concentrations of conservative major solutes in the porewaters of alpine, ombrotrophic bogs are the net effect of both downward vertical porewater movement and upward vertical diffusion, the magnitudes of which are delicately poised to the configuration of the bog water table over time and subsurface peat stratigraphy.

  13. Combined molecular ecological and confocal laser scanning microscopic analysis of peat bog methanogen populations.

    PubMed

    Upton, M; Hill, B; Edwards, C; Saunders, J R; Ritchie, D A; Lloyd, D

    2000-12-15

    Confocal laser scanning microscopy, using fluorescently labelled oligonucleotide probes targeting the 16S rRNA of different physiological groups of methanogens, was used to identify which methanogenic genera were present and to describe their in situ spatial locations in samples taken at different depths from blanket peat bog cores. Total bacterial DNA was also extracted and purified from the samples and used as template for amplification of 16S rRNA and regions of methyl CoM reductase-encoding genes using the polymerase chain reaction, as well as for oligonucleotide hybridisation experiments. These techniques, used in concert, demonstrated that methanogens of several physiological groups were present in highest numbers in the mid regions of 25 cm deep peat cores. Some discrepancies were apparent in the findings of the microscopic and molecular methods, though these may be partially accounted for by the different sensitivities of the techniques employed. The combined approaches used in this study gave an insight into the diversity and distribution of methanogens in peat environments not possible using molecular ecological methods alone.

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

    NASA Astrophysics Data System (ADS)

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

    2005-12-01

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

  15. Superfund record of decision (EPA Region 2): Burnt Fly Bog, Marlboro Township, NJ, September 30, 1998

    SciTech Connect

    1999-03-01

    This decision document presents the selected remedial action for the Westerly Wetlands, Northerly Wetlands, and Tar Patch Area at the Burnt Fly Bog Superfund Site. It addresses contaminated soil present on the three remaining contaminated areas on the Site, including the Westerly Wetlands, Northerly Wetlands, and Tar Patch Area. The major components of the selected remedy include: Excavation and off-site disposal of contaminated soil from the Northerly Wetlands; Excavation and off-site disposal of contaminated soil from the Tar Patch Area; Backfilling the excavated area in the Northerly Wetland and reestablishing wetlands; Backfilling the excavated area in the Tar Patch Area and creating wetlands; Provision of additional security fencing around the Westerly Wetlands, and the recording of a Deed Notice for the Westerly Wetlands, Northerly Wetlands, and Tar Patch Area; Monitoring of surface water and sediment in the Westerly Wetlands, surface water and sediment in the existing sedimentation basin located in the Downstream Area, and surface water, sediment and, if necessary, biota in Burnt Fly Brook; and Biological sampling in the Westerly Wetlands.

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

    PubMed

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

    2013-01-01

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

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

    NASA Technical Reports Server (NTRS)

    Sebacher, D. I.; Harriss, R. C.; Grice, S. S.; Bartlett, K. B.; Sebacher, S. M.

    1986-01-01

    Methane (CH4) flux measurements from Alaska 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 per sq m per day (moist tundra) to 119 mg CH4 per sq m per day (waterlogged tundra). Fluxes averaged 40 mg CH4 per sq m per day from wet tussock meadows in the Brooks Range and 289 mg Ch4 per sq m per day from an alpine fen in the Alaskan Range. The boreal marsh had an average CH4 emission rate of 106 mg CH4 per sq m per day. Significant emissions were detected in tundra areas where peat temperatures were as low as 4 C, and permafrost was only 25 cm below the ground surface. Emission rates from the 17 sites sampled were found to be logarithmically related to water levels at the sites. Extrapolation of the data to an estimate of the total annual CH4 emission from all arctic and boreal wetlands suggests that these ecosystems are a major source of atmospheric CH4 and could account for up to 23 percent of global CH4 emissions from wetlands.

  18. Variation in methane production pathways associated with permafrost decomposition in collapse scar bogs of Alberta, Canada

    NASA Astrophysics Data System (ADS)

    Prater, James L.; Chanton, Jeffrey P.; Whiting, Gary J.

    2007-12-01

    Stable isotope analysis was used to determine the distribution of methanogenic pathways at permafrost collapse scar bogs to test the hypothesis that microbial respiration and methane production are stimulated by the input of organic matter associated with permafrost degradation and collapse. An alternative hypothesis is that recently assimilated carbon produced by the fen-like vegetation (Carex, Eriophorum) growing in open water moats formed by the collapsing edge of these features stimulates microbial respiration. We found that CO2 reduction was the dominant pathway for methanogenesis within the Sphagnum areas that dominate the surface cover of these features, but relatively more acetate fermentation occurred near collapse scar moats. Methane emission and net CO2 uptake were correlated. Both were elevated in collapse scar moats and then decreased along a transect from the moats toward the center Sphagnum-dominated areas. There also appeared to be a shift toward relatively more acetate fermentation in deeper samples associated with increasing cation (calcium and magnesium) concentrations. Our results indicate that organic inputs from permafrost degradation alone do not appear to stimulate acetate fermentation. Permafrost decomposition provides conditions along the collapsing edge that are conducive to colonization by fen-like vegetation that stimulates acetate fermentation and increases methane production and emission rates.

  19. Novosphingobium aquaticum sp. nov., isolated from the humic-matter-rich bog lake Grosse Fuchskuhle.

    PubMed

    Glaeser, Stefanie P; Bolte, Kathrin; Busse, Hans-Jürgen; Kämpfer, Peter; Grossart, Hans-Peter; Glaeser, Jens

    2013-07-01

    A yellow-pigmented, Gram-negative rod, designated FNE08-86(T), was isolated from subsurface water of the humic-matter-rich and almost-neutral north-east basin of the experimentally divided bog lake Grosse Fuchskuhle (Brandenburg, Germany). Analysis of the nearly full-length 16S rRNA gene sequence showed the highest 16S rRNA gene sequence similarity with Novosphingobium rosa IAM 14222(T) (96.3 %). Sequence similarities with all other members of the genus Novosphingobium species were <96 %, but phylogenetic tree construction clearly showed the placement of strain FNE08-86(T) within the genus Novosphingobium. The predominant fatty acids were C18 : 1ω7c and C16 : 0, and only a single 2-hydroxy fatty acid, C14 : 0 2-OH, was detected. The polar lipid profile revealed phosphatidylethanolamine, phosphatidylglycerol and phosphatidylcholine as major compounds, with smaller amounts of sphingoglycolipid, phosphatidylmonomethylethanolamine, diphosphatidylglycerol and several unidentified lipids. In the quinone system ubiquinone Q-10 was predominant and in the polyamine pattern spermidine was predominant. Characterization by genotypic, chemotaxonomic and phenotypic analysis indicated that strain FNE08-86(T) represents a novel species of the genus Novosphingobium, for which we propose the name Novosphingobium aquaticum sp. nov. (type strain FNE08-86(T) = DSM 25088(T) = CCM 7983(T)).

  20. Methanoregula boonei gen. nov., sp. nov., an acidiphilic methanogen isolated from an acidic peat bog.

    PubMed

    Bräuer, Suzanna L; Cadillo-Quiroz, Hinsby; Ward, Rebekah J; Yavitt, Joseph B; Zinder, Stephen H

    2011-01-01

    A novel acidiphilic, hydrogenotrophic methanogen, designated strain 6A8(T), was isolated from an acidic (pH 4.0-4.5) and ombrotrophic (rain-fed) bog located near Ithaca, NY, USA. Cultures were dimorphic, containing thin rods (0.2-0.3 μm in diameter and 0.8-3.0 μm long) and irregular cocci (0.2-0.8 μm in diameter). The culture utilized H(2)/CO(2) to produce methane but did not utilize formate, acetate, methanol, ethanol, 2-propanol, butanol or trimethylamine. Optimal growth conditions were near pH 5.1 and 35 °C. The culture grew in basal medium containing as little as 0.43 mM Na(+) and growth was inhibited completely by 50 mM NaCl. To our knowledge, strain 6A8(T) is one of the most acidiphilic (lowest pH optimum) and salt-sensitive methanogens in pure culture. Acetate, coenzyme M, vitamins and yeast extract were required for growth. It is proposed that a new genus and species be established for this organism, Methanoregula boonei gen. nov., sp. nov. The type strain of Methanoregula boonei is 6A8(T) (=DSM 21154(T) =JCM 14090(T)).

  1. Late Holocene peatland carbon dynamics inferred from Teringi Bog in southern Estonia

    NASA Astrophysics Data System (ADS)

    Hill, Kristyn; Stansell, Nathan; Klein, Eric; Borges, Alberto

    2015-04-01

    Radiocarbon dated peat cores collected along a transect from Teringi Bog, an ombotrophic peatland, record changes in carbon accumulation rates during the late Holocene in response to shifting climatic conditions. Stable oxygen isotope records from nearby lakes indicate that periods of wetter conditions during the Holocene occurred at times when carbon accumulation rates were higher at Teringi. This suggests that shifting water table conditions drove much of the observed changes in carbon dynamics. Modern surface process observations indicate that carbon accumulation rates are indeed more variable at locations where the height of the water table is highly sensitive to rainfall amounts. In addition, carbon isotopes measured on water samples indicate that there is a close relationship between δ13C values and methane concentrations, suggesting that methanogenesis is strongly biomediated, and likewise varies as a function of the regional hydrology. Regardless, all of the cores collected indicate that there was a trend toward higher carbon accumulation rates from ~4.2 to 3.5 ka when precipitation amounts were higher, followed by lower values under drier conditions until ~2.8 ka. There was then a trend toward higher carbon accumulation rates through the remaining late Holocene. These observations further highlight the importance of high latitude peatland in global carbon dynamics as both a potential sink and source of CO2 and CH4.

  2. Atmospheric Deposition of Indium in the Northeastern United States: Flux and Historical Trends.

    PubMed

    White, Sarah Jane O; Keach, Carrie; Hemond, Harold F

    2015-11-03

    The metal indium is an example of an increasingly important material used in electronics and new energy technologies, whose environmental behavior and toxicity are poorly understood despite increasing evidence of detrimental health impacts and human-induced releases to the environment. In the present work, the history of indium deposition from the atmosphere is reconstructed from its depositional record in an ombrotrophic bog in Massachusetts. A novel freeze-coring technique is used to overcome coring difficulties posed by woody roots and peat compressibility, enabling retrieval of relatively undisturbed peat cores dating back more than a century. Results indicate that long-range atmospheric transport is a significant pathway for the transport of indium, with peak concentrations of 69 ppb and peak fluxes of 1.9 ng/cm2/yr. Atmospheric deposition to the bog began increasing in the late 1800s/early 1900s, and peaked in the early 1970s. A comparison of deposition data with industrial production and emissions estimates suggests that both coal combustion and the smelting of lead, zinc, copper, and tin sulfides are sources of indium to the atmosphere in this region. Deposition appears to have decreased considerably since the 1970s, potentially a visible effect of particulate emissions controls instated in North America during that decade.

  3. Brief communication: Two and three-dimensional analysis of bone mass and microstructure in a bog body from the Iron Age.

    PubMed

    Schilling, Arndt F; Kummer, Tobias; Marshall, Robert P; Bauerochse, Andreas; Jopp, Eilin; Pueschel, Klaus; Amling, Michael

    2008-04-01

    Human remains from peat bogs, called "bog bodies," have yielded valuable insights into human history because of their excellent preservation of soft tissue. On the other hand, the acidic environment of the peat leads to an extensive demineralization of skeletal elements, complicating their analysis. We studied the skeleton of the bog body "Moora" dated to approximately 650 B.C. Nondestructive evaluation of the bone was made using contact X-rays, peripheral quantitative computed tomography (pQCT) analysis, multislice computed tomography (CT) and high resolution micro computed tomography (microCT) imaging. Two thousand seven hundred years in the acidic environment of the bog led to a loss of 92.7% of bone mineral density. Despite this demineralization and in contrast to other bog bodies, the spatial structure of the bones of "Moora" is exceptionally well preserved. We found Harris lines and were able to obtain the first three-dimensional data on the trabecular microstructure of the bone of a young woman from the early Iron Age.

  4. How will the semi-natural vegetation of the UK have changed by 2030 given likely changes in nitrogen deposition?

    PubMed

    Stevens, Carly J; Payne, Richard J; Kimberley, Adam; Smart, Simon M

    2016-01-01

    Nitrogen deposition is known to have major impacts on contemporary ecosystems but few studies have addressed how these impacts will develop over coming decades. We consider likely changes to British semi-natural vegetation up to the year 2030 both qualitatively, based on knowledge of species responses from experimental and gradient studies, and quantitatively, based on modelling of species relationships in national monitoring data. We used historical N deposition trends and national predictions of changing deposition to calculate cumulative deposition from 1900 to 2030. Data from the Countryside Survey (1978, 1990 and 1998) was used to parameterise models relating cumulative N deposition to Ellenberg N which were then applied to expected future deposition trends. Changes to habitat suitability for key species of grassland, heathland and bog, and broadleaved woodland to 2030 were predicted using the MultiMOVE model. In UK woodlands by 2030 there is likely to be reduced occurrence of lichens, increased grass cover and a shift towards more nitrophilic vascular plant species. In grasslands we expect changing species composition with reduced occurrence of terricolous lichens and, at least in acid grasslands, reduced species richness. In heaths and bogs we project overall reductions in species richness with decreased occurrence of terricolous lichens and some bryophytes, reduced cover of dwarf shrubs and small increases in grasses. Our study clearly suggests that changes in vegetation due to nitrogen deposition are likely to continue through coming decades.

  5. Importance of automobile exhaust catalyst emissions for the deposition of platinum, palladium, and rhodium in the northern hemisphere.

    PubMed

    Rauch, Sebastien; Hemond, Harold F; Barbante, Carlo; Owari, Masanori; Morrison, Gregory M; Peucker-Ehrenbrink, Bernhard; Wass, Urban

    2005-11-01

    An estimated 500 million vehicles worldwide are equipped with an exhaust catalyst that uses platinum group elements (PGE) as the main active components and thus contribute to global PGE emissions. Although PGE emitted from automobile exhaust catalysts were first believed to remain in the roadside environment, we propose here that fine PGE-containing particles in automobile exhaust have resulted in a widespread distribution of emitted PGE. Regional and long-range transport of PGE from automobile exhaust catalysts is supported by elevated PGE deposition in both a peat bog located 250 m from traffic and in central Greenland, respectively. Russian smelters were also found to contribute to PGE contamination in central Greenland. Deposition rates estimated for the roadside environment, the peat bog, and central Greenland were used to provide a first estimate of PGE deposition in the northern hemisphere. The results show that deposition of regionally or long-range transported PGE accounts for a large fraction of total PGE deposition, and PGE deposition in the roadside environment represents less than 5% of the total deposition. Transport at the regional and global scales represents an important component in the environmental cycle of emitted PGE and needs to be further studied to fully assess the environmental fate of PGE from automobile exhaust catalysts.

  6. Impact of long term wetting on pore water chemistry in a peat bog in Ontario, Canada

    NASA Astrophysics Data System (ADS)

    Schaper, Jonas; Blodau, Christian; Holger Knorr, Klaus

    2013-04-01

    Peatlands of the northern hemisphere store a remarkable amount of carbon but also contribute to global methane emissions. As large areas in the boreal and subarctic zone are considered to undergo significant climate change it is necessary to understand how these ecosystems react to altered environmental conditions. Since not only temperatures but also precipitation is likely to increase in these regions, it is of particular interest to understand the impact of raised water tables and changing local hydrological flow patterns on peatlands' carbon cycle. We chose a pristine bog that was partly flooded by a reservoir lake created 60 years ago in Ontario, Canada. Water management in the reservoir resulted in seasonal flooding, shifting hydrological flow patterns and vegetation gradients. The impact of partial flooding on pore water chemistry and DIC and CH4 concentrations were studied within surface peat layers. Samples were taken with pore water peepers along the vegetation- and flooding gradient. Turnover rates of DIC and methane were calculated from obtained concentration profiles and peat porosity under the assumption that transport is dominated by diffusion. Values of pH changed remarkably from 4 within the undisturbed bog part to almost 8 at the lake shore. Ca2+ and Mg2+ were the only ions that showed significant distribution patterns with readily increasing concentrations towards the lake water body. CH4 and DIC concentrations also increased towards the lake and peaked in around 100 cm depth right at the shore with maximum concentrations being 2766 μmol L-1 for CH4 and 7543 μmol L-1 for DIC, respectively. Turnover rates also increased towards the shore albeit some uncertainty lies in this finding as steady state condition required for calculations were probably not established and transport was not only dominated by diffusion. Maximum CH4 production rates were modeled to be 36 nmol cm-3 d-1 and maximum DIC production was calculated to 64 nmol cm-3 d-1. Ca2

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

    NASA Astrophysics Data System (ADS)

    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

  8. Response of Sphagnum fuscum to Nitrogen Deposition: A Case Study of Ombrogenous Peatlands in Alberta, Canada

    USGS Publications Warehouse

    Vitt, D.H.; Wieder, K.; Halsey, L.A.; Turetsky, M.

    2003-01-01

    Peatlands cover about 30% of northeastern Alberta and are ecosystems that are sensitive to nitrogen deposition. In polluted areas of the UK, high atmospheric N deposition (as a component of acid deposition) has been considered among the causes of Sphagnum decline in bogs (ombrogenous peatlands). In relatively unpolluted areas of western Canada and northern Sweden, short-term experimental studies have shown that Sphagnum responds quickly to nutrient loading, with uptake and retention of nitrogen and increased production. Here we examine the response of Sphagnum fuscum to enhanced nitrogen deposition generated during 34 years of oil sands mining through the determination of net primary production (NPP) and nitrogen concentrations in the upper peat column. We chose six continental bogs receiving differing atmospheric nitrogen loads (modeled using a CALPUFF 2D dispersion model). Sphagnum fuscum net primary production (NPP) at the high deposition site (Steepbank - mean of 600 g/m2; median of 486 g/m2) was over three times as high than at five other sites with lower N deposition. Additionally, production of S. fuscum may be influenced to some extent by distance of the moss surface from the water table. Across all sites, peat nitrogen concentrations are highest at the surface, decreasing in the top 3 cm with no significant change with increasing depth. We conclude that elevated N deposition at the Steepbank site has enhanced Sphagnum production. Increased N concentrations are evident only in the top 1-cm of the peat profile. Thus, 34 years after mine startup, increased N-deposition has increased net primary production of Sphagnum fuscum without causing elevated levels of nitrogen in the organic matter profile. A response to N-stress for Sphagnum fuscum is proposed at 14-34 kg ha-1 yr-1. A review of N-deposition values reveals a critical N-deposition value of between 14.8 and 15.7 kg ha -1 yr-1 for NPP of Sphagnum species.

  9. Variations of 18O/ 16O in plants from temperate peat bogs (Switzerland): implications for paleoclimatic studies

    NASA Astrophysics Data System (ADS)

    Ménot-Combes, Guillemette; Burns, Stephen J.; Leuenberger, Markus

    2002-09-01

    Despite the great potential of peat bogs as climatic archives, to date only few studies have focused on the climatic controls on cellulose isotopic composition in modern bog plants. This study attempts to calibrate plant-climate relationships by sampling a set of modern plant species (both vascular plants and mosses) and bog surface waters along an altitude transect in Switzerland. Isotopic analyses of water samples show that the δ 18O-values of surface bog waters follow the trend of precipitation despite significant scatter in the data set. Detailed sampling of surface waters within one bog shows that δ 18O-values vary widely and are closely related to the micro-topography of the bog surface. More enriched 18O/ 16O ratios in water samples collected from small raised hummocks than the ones collected from hollows are documented in both horizontal and vertical profiles. A δ 18O-δD plot indicates that the process leading to the isotopic enrichment of the uppermost surface waters is evaporation, greater above Sphagnum covered hummocks than above open pools. To investigate the implications of such high variability of source water for plant α-cellulose δ 18O-values, a detailed study of both surface water and α-cellulose δ 18O-values within one site is conducted. The large δ 18O variability observed in surface waters is found to be considerably smoothed in α-cellulose (by a factor of 5-10 depending on the plant species). This indicates that the water used by plant photosynthetic processes reflects the isotopic composition of the average annual precipitation. This points to a source water level for plants of a few decimeters where the variations are smaller than at the air-water interface. The response of the α-cellulose δ 18O to the environmental gradient along the altitude transect varies considerably from species to species. For most of the species studied, the δ 18O-values decrease with altitude, following the trends of δ 18O-values in precipitation and

  10. Hydrological responses to managed burning and grazing in an upland blanket bog

    NASA Astrophysics Data System (ADS)

    Clay, Gareth D.; Worrall, Fred; Clark, Emma; Fraser, Evan D. G.

    2009-10-01

    SummaryThe management of the UK uplands by rotational burning and grazing is a widespread practice that aims to control the development of vegetation in order to create suitable habitats for grouse and sheep. By modifying the above ground biomass it is possible that above and/or below ground hydrological regimes may be altered. This study investigates the effect burning has on various hydrological parameters of an upland blanket bog. The study was conducted on a long-term experimental site examining different combinations of managed burning and grazing intensities. The study has found that: Although depth to water table shows strong seasonal trends, the shallowest water tables were found on those sites that were burnt every 20 years and grazed by sheep. The deepest water tables were found on those sites that had never been burnt. In the year following a managed burn, water tables on those sites that were burnt were significantly shallower than before the burn. Hydraulic conductivity, as determined by dipwell slug tests, was found to be significantly lower on those plots that were burnt every 20 years. Runoff occurrence was recorded and occurred at a significantly greater frequency on those sites that had recently been burnt. By using antecedent weather conditions, significant parameters were found that could be used to model runoff generation. This paper demonstrates how the use of managed burning in upland settings can affect various hydrological responses of the peatland. These variations in hydrological response will have important consequences on DOC export through changes in water table and the partitioning of precipitation into runoff.

  11. Modeling seasonal to annual carbon balance of Mer Bleue Bog, Ontario, Canada

    NASA Astrophysics Data System (ADS)

    Frolking, Steve; Roulet, Nigel T.; Moore, Tim R.; Lafleur, Peter M.; Bubier, Jill L.; Crill, Patrick M.

    2002-07-01

    Northern peatlands contain enormous quantities of organic carbon within a few meters of the atmosphere and play a significant role in the planetary carbon balance. We have developed a new, process-oriented model of the contemporary carbon balance of northern peatlands, the Peatland Carbon Simulator (PCARS). Components of PCARS are (1) vascular and nonvascular plant photosynthesis and respiration, net aboveground and belowground production, and litterfall; (2) aerobic and anaerobic decomposition of peat; (3) production, oxidation, and emission of methane; and (4) dissolved organic carbon loss with drainage water. PCARS has an hourly time step and requires air and soil temperatures, incoming radiation, water table depth, and horizontal drainage as drivers. Simulations predict a complete peatland C balance for one season to several years. A 3-year simulation was conducted for Mer Bleue Bog, near Ottawa, Ontario, and results were compared with multiyear eddy covariance tower CO2 flux and ancillary measurements from the site. Seasonal patterns and the general magnitude of net ecosystem exchange of CO2 were similar for PCARS and the tower data, though PCARS was generally biased toward net ecosystem respiration (i.e., carbon loss). Gross photosynthesis rates (calculated directly in PCARS, empirically inferred from tower data) were in good accord, so the discrepancy between model and measurement was likely related to autotrophic and/or heterotrophic respiration. Modeled and measured methane emission rates were quite low. PCARS has been designed to link with the Canadian Land Surface Scheme (CLASS) land surface model and a global climate model (GCM) to examine climate-peatland carbon feedbacks at regional scales in future analyses.

  12. Paenibacillus frigoriresistens sp. nov., a novel psychrotroph isolated from a peat bog in Heilongjiang, Northern China.

    PubMed

    Ming, Hong; Nie, Guo-Xing; Jiang, Hong-Chen; Yu, Tian-Tian; Zhou, En-Min; Feng, Hui-Gen; Tang, Shu-Kun; Li, Wen-Jun

    2012-08-01

    A novel cold-resistant bacterium, designated YIM 016(T), was isolated from a peat bog sample collected from Mohe County, Heilongjiang Province, Northern China and its taxonomic position was investigated using a polyphasic approach. The strain was Gram-positive, aerobic, endospore-forming, motile and rod-shaped. Phylogenetic analyses based on the 16S rRNA gene sequence clearly revealed that strain YIM 016(T) is a member of the genus Paenibacillus. The strain is closely related to Paenibacillus alginolyticus DSM 5050(T), Paenibacillus chondroitinus DSM 5051(T) and Paenibacillus pocheonensis Gsoil 1138(T) with similarities of 99.0 %, 97.0 % and 96.3 %, respectively. Meanwhile, the low DNA-DNA relatedness levels between strain YIM 016(T) and its closely related phylogenetic neighbours demonstrated that this isolate represents a new genomic species in the genus Paenibacillus. Phenotypic and chemotaxonomic tests showed that growth of strain YIM 016(T) occurred at 4-37 °C, pH 6.0-8.0 and with a NaCl tolerance up to 0.5 % (w/v). The peptidoglycan contained meso-diaminopimelic acid, alanine and glutamic acid. The whole-cell hydrolysates mainly contained glucose, galactose and ribose. The predominant menaquinone was MK-7 and the major fatty acids were anteiso-C(15:0) and iso-C(16:0). The DNA G+C content of strain YIM 016(T) was 51.7 mol %. On the basis of phylogenetic, phenotypic and chemotaxonomic characteristics, strain YIM 016(T) could be clearly distinguished from other species of the genus Paenibacillus. It is therefore concluded that strain YIM 016(T) represents a novel species in the genus Paenibacillus, for which the name Paenibacillus frigoriresistens sp. nov. is proposed. The type strain is YIM 016(T) (= CCTCC AB 2011150(T) = JCM 18141(T)).

  13. Bog bilberry anthocyanin extract improves motor functional recovery by multifaceted effects in spinal cord injury.

    PubMed

    Wang, Jun; Ma, Chuan; Rong, Wei; Jing, Hao; Hu, Xing; Liu, Xiaoguang; Jiang, Liang; Wei, Feng; Liu, Zhongjun

    2012-12-01

    The aim of this study was to determine the therapeutic efficiency of bog bilberry anthocyanin extract (BBAE) treatment starting 1 d after spinal cord injury (SCI) in rats and to investigate the underlying mechanism. The BBAE contained cyanidin-3-glucoside, malvidin-3-galactoside and malvidin-3-glucoside. SCI models were induced using the weight-drop method in Sprague-Dawley rats and additionally with sham group (laminectomy only). The animals were divided into four groups: vehicle-treated group; 10 mg/kg BBAE-treated group; 20 mg/kg BBAE-treated group; sham group. BBAE-treated or vehicle-treated group was administered orally at one day after SCI and then daily for 8 weeks. Locomotor functional recovery was assessed during the 8 weeks post operation period by performing a Basso, Beattie, and Bresnahan (BBB) locomotor score test. At the end of study, the animals were killed, and 1.5 cm segments of spinal cord encompassing the injury site were removed for immunohistochemistry, histopathological and western blotting analysis. Immunohistochemistry for GFAP, aggrecan, neurocan and NeuN was used to assess the degree of astrocytic glial scar formation and neuron survival. Immunohistochemistry and western blotting analysis for TNF-α, IL-6, IL-1β was used to evaluate the anti-inflammation effect of BBAE. To evaluate its inhibition effect on the astrocytes, we performed the MTT assay and immunohistochemistry for Ki67 in vitro. Results show that the BBAE-treated animals showed significantly better locomotor functional recovery, neuron death and smaller glial scar formation after spinal cord injury in vivo. In addition, BBAE administration could inhibit astrocyte proliferation in vivo and vitro. Therefore, BBAE may be useful as a promising therapeutic agent for SCI.

  14. Influence of water table on carbon dioxide, carbon monoxide, and methane fluxes from taiga bog microcosms

    SciTech Connect

    Funk, D.W.; Pullmann, E.R.; Peterson, K.M.

    1994-09-01

    Hydrological changes, particularly alterations in water table level, may largely overshadow the more direct effects of global temperature increase upon carbon cycling in arctic and subarctic wetlands. Frozen cores (n=40) of intact soils and vegetation were collected from a bog near Fairbanks, Alaska, and fluxes of CO{sub 2}, CH{sub 4}, and Co in response to water table variation were studied under controlled conditions in the Duke University phytotron. Core microcosms thawed to a 20-cm depth over 30 days under a 20 hour photoperiod with a day/night temperature regime of 20/10{degrees}C. After 30 days the water table in 20 microcosms was decreased from the soil surface to -15 cm and maintained at the soil surface in 20 control cores. Outward fluxes of CO{sub 2} (9-16 g m{sup -2}d{sup -1}) and CO (3-4 mg m{sup -2}d{sup -1}) were greatest during early thaw and decreased to near zero for both gases before the water table treatment started. Lower water table tripled CO{sub 2} flux to the atmosphere when compared with control cores. Carbon monoxide was emitted at low rates from high water table cores and consumed by low water table cores. Methane fluxes were low (<1 mg m{sup -2}d{sup -1}) in all cores during thaw. High water table cores increased CH{sub 4} flux to 8-9 mg m{sup -2}d{sup -1} over 70 days and remained high relative to the low water table cores (<0.74 mg m{sup -2}d{sup -1}). Although drying of wetland taiga soils may decrease CH{sub 4} emissions to the atmosphere, the associated increase in CO{sub 2} due to aerobic respiration will likely increase the global warming potential of gas emissions from these soils. 43 refs., 4 figs.

  15. Spatio-temporal natural and anthropogenic environmental variability during the last 1500yrs in an ombrotrophic bog (East Belgium).

    NASA Astrophysics Data System (ADS)

    de Vleeschouwer, François; Fagel, Nathalie; Allan, Mohammed; Javaux, Emmanuelle; Gerrienne, Philippe; Streel, Maurice; Luthers, Cédric; Hindrycks, Marie-Noëlle; Wastiaux, Cécile; Leclercq, Louis

    2010-05-01

    Peatlands cover ca. 3 % of the Earth's surface and provide crucial continental archives for deciphering past climatic changes and anthropogenic impacts on decadal to millennial timescales. Numerous studies have demonstrated that peat bogs are excellent archives to investigate past environmental and ecological changes during the Holocene. Studies which focus on intra-site variability at high resolution are rare however, despite their potential to provide constraints on the reliability of the palaeoenvironmental reconstruction and the influence of micro-scale variability. Such variability must be taken into account in any peatland restoration process linked with recent environmental changes, particularly human-derived impact such as peat cutting, drainage and tree cultivation. Four 1m-long Wardenaar monoliths were retrieved from the Misten bog (Hautes-Fagnes, East Belgium). The cores were investigated using chronological (radiocarbon AMS dating of plant macrofossils, 210Pb age modelling), biological (macrofossils, pollen content, testate amoebae), organic (humification level) and geochemical proxies (major and trace geochemistry, Nd and Pb isotopes). The aims of this research were to: (1) to assess whether the bog vegetation and other environmental indicators have changed simultaneously in time and space, (2) identify the most sensitive palaeoenvironmental indicator(s) and (3) assess to what extent variation in peat accumulation rates affects the record of each proxy. Preliminary interpretations show great variability (up to 50%) in peat development on a decimetre depth-scale as assessed by the variation in peat palynological and macrofossils zones from one core to another. In addition, our recent high-resolution records of environmental change have high applied palaeoecological value since they can be used to inform conservation management (‘natural' changes in the composition of the peat forming vegetation and the range of water table depth variability over a

  16. [Analysis of genetic structure and differentiation of the bog and dry land populations of Pinus sibirica du tour based on nuclear microsatellite loci].

    PubMed

    Oreshkova, N V; Sedel'nikova, T S; Pimenov, A V; Efremov, S P

    2014-09-01

    We evaluated the population structure of the bog and dry land populations of the Siberian pine Pinus sibirica (P. sibrica) in Western Siberia using nuclear genome markers. Six pairs of nuclear microsatellite loci were used for this analysis. We detected 30 allelic variants in 120 individuals of four populations of P. Sibirica. We established that the studied populations differ by genetic structure. The most essential differences were identified between the Siberian pine population from oligotrophic bog and the group of populations from dry land within eutrophic bogs and near settlements P. sibirica forest (F(ST) = 0.019; D(N) = 0.053). We estimated that diversification of the West Siberian populations of P. sibirica exceeded 2.4% (F(ST) = 0.024), based on an analysis of SSR markers.

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

    NASA Astrophysics Data System (ADS)

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

    2010-04-01

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

  18. Modeling CH4 and CO2 cycling using porewater stable isotopes in a thermokarst bog, interior Alaska

    NASA Astrophysics Data System (ADS)

    Neumann, R. B.; Blazewicz, S.; Waldrop, M. P.

    2014-12-01

    Methane emitted from wetlands represents the end product of various microbial processes operating within anaerobic wetland soils. Determining the rate at which these microbial reactions occur is challenging, making it difficult to gain a mechanistic understanding of the factors and conditions that influence microbial rates and ultimately methane emissions. One approach for estimating in-situ reaction rates involves tracking the time evolution of porewater concentrations and stable carbon isotopes of CH4 and CO2. Microbes preferentially use isotopically light carbon substrates, which causes the carbon product pool to become isotopically lighter and the carbon substrate pool become isotopically heavier. Different microbial biochemical pathways fractionate carbon to different extents, allowing for differentiation between microbial reactions. This is a powerful approach to estimate in-situ rates, but, as we show in our presentation, it is possible for different combinations of reaction rates to provide equally good fits to the evolution of these data. The solution is non-unique and depends on the set of considered reactions. We used two different reaction network models on a set of porewater data collected from a thermokarst bog at the Alaska Peatland Experiment (APEX) outside of Fairbanks, AK to estimate in-situ microbial reaction rates during the summer season. Both models included methane production, methane oxidation and fermentation/respiration, but only one model included homoacetogenesis. We found that both reaction networks explained the evolution of dissolved gas concentrations and stable carbon isotope data, but predicted rates that differed from each other by up to a factor of six. The methane production rates estimated by the model that included homoacetogenesis aligned better with measured rates of methane emission. Despite differences in the magnitude of modeled rates, results from the two models told a similar story about the spatial and temporal

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

    PubMed

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

    2013-06-01

    Trace element concentrations in the Roñanzas peat bog record reveal a contribution of natural processes but the influence of anthropogenic factors predominates in the last two millenniums, particularly aerosol deposition linked to mining and industrial activities in northern Spain. We observed that the Roñanzas record can be considered a preserved environment, suitable to search for local (<50 km), regional (50-150 km) and/or long-distance human activity fingerprinting, specifically that related to the deposition of heavy metals such as Pb, Zn and Hg. We also carried out a multivariate statistical study in order to clarify the geochemical behavior of trace and major elements. Our study design represents a novel approach to assign natural vs. human contributions in peatlands. Therefore, synergies obtained by the simultaneous study of multivariate statistics and enrichment factors allow robust conclusions about paleoenvironmental evolution and human activities. Anthropogenic influence has also been reported in similar records in other parts of Europe, thereby suggesting large-scale sources for atmospheric pollution. However, here we revealed remarkable particularities, such as the association of Cd, Zn and Pb, mainly linked to regional and local factors (mining and more recently the metallurgical industry), whereas we propose that the occurrence of Hg is associated with a combination of regional factors and global atmospheric pollution.

  20. Concentration and grain-size distribution of aeolian sands in peat bogs as an indicator of past storminess in coastal areas of Estonia

    NASA Astrophysics Data System (ADS)

    Vandel, Egert; Vaasma, Tiit; Tõnisson, Hannes; Sugita, Shinya; Vilumaa, Kadri; Anderson, Agnes; Terasmaa, Jaanus; Kangur, Mihkel; Pensa, Margus; Küttim, Martin; Umbleja, Liisa; Puusepp, Liisa

    2016-04-01

    Storminess in the Baltic Sea region has significantly increased over the last 50 years. As we do not have meteorological data beyond 20th century, therefore the long-term changes in storminess (e.g., frequency and magnitude of the storms) and its impact on the coastal evolution are mostly unknown. This study aims to reconstruct the extreme storm events along the coast of Estonia in late Holocene, inferred from changes in grain-size distribution and concentration of aeolian sands preserved in peat deposits. Four cores in total were collected from bogs of coastal Estonia; three from west Estonian archipelago (Hiiumaa Island and Saaremaa Island); one from the northern coast of the mainland (Juminda Peninsula). Core from Saaremaa (166 cm) covers the last 2700 years, cores from Hiiumaa (171 cm and 330 cm) cover ca 4000 years, and core from Juminda (465 cm) covers ca 8500 years. All AMS dates (77) are converted to cal yrs BP. Analyses of LOI and grain size are carried out at every centimetre in order to obtain data for mineral matter content and concentration of sand particles. The Juminda core shows a consistently low content of mineral matter (LOI < 2%) without clear peaks over the last 8000 years. The LOI results at both Hiiumaa sites show that mineral matter content gradually decreases from 4000 to 1500 cal yrs BP and then becomes the lowest in the period of 1500-1000 cal yrs BP; since then, it becomes higher (up to 10%) with fluctuations and has a clear peak around 700 cal yrs BP. At Saaremaa, the overall trend of mineral matter content is similar to that at the Hiiumaa sites: gradual decline from 2700 to 1500 cal yrs BP, lowest in 1500-1000 cal yrs BP, and relatively high over the last millennium. Concentration of mineral particles reveal clear peaks of aeolian sands at each site. At northern Hiiumaa, concentration has peaks around 3500, 3000 and 2500 cal yrs BP and is relatively high over the last 700 years. At Saaremaa, concentration has peaked at 2100, 1600 and

  1. Reliance on prey-derived nitrogen by the carnivorous plant Drosera rotundifolia decreases with increasing nitrogen deposition.

    PubMed

    Millett, J; Svensson, B M; Newton, J; Rydin, H

    2012-07-01

    • Carnivory in plants is presumed to be an adaptation to a low-nutrient environment. Nitrogen (N) from carnivory is expected to become a less important component of the N budget as root N availability increases. • Here, we investigated the uptake of N via roots versus prey of the carnivorous plant Drosera rotundifolia growing in ombrotrophic bogs along a latitudinal N deposition gradient through Sweden, using a natural abundance stable isotope mass balance technique. • Drosera rotundifolia plants receiving the lowest level of N deposition obtained a greater proportion of N from prey (57%) than did plants on bogs with higher N deposition (22% at intermediate and 33% at the highest deposition). When adjusted for differences in plant mass, this pattern was also present when considering total prey N uptake (66, 26 and 26 μg prey N per plant at the low, intermediate and high N deposition sites, respectively). The pattern of mass-adjusted root N uptake was opposite to this (47, 75 and 86 μg N per plant). • Drosera rotundifolia plants in this study switched from reliance on prey N to reliance on root-derived N as a result of increasing N availability from atmospheric N deposition.

  2. The geochemistry of water near a surficial organic-rich uranium deposit, northeastern Washington State, U.S.A.

    USGS Publications Warehouse

    Zielinski, R.A.; Otton, J.K.; Wanty, R.B.; Pierson, C.T.

    1987-01-01

    The chemistry of three stream, three spring and six near-surface waters in the vicinity of a Holocene organic-rich uranium deposit is described, with particular emphasis on the chemistry of U. Results characterize the solution behavior of uranium as U-bearing water interacts with relatively undecomposed, surficial organic matter. Of the measured major and trace chemical species, only U is consistently highly enriched (17-318 ppb) relative to reported values for regional waters, or to literature values for waters in largely granitic terrains. R-mode factor analysis of the chemical data suggests that most U is present in a soluble form, but that some U is also associated with fine suspended particulates of clay, organic matter, or hydrous oxides. Calculations that apply thermodynamic data to predict U speciation in solution indicate the relative importance of uranyl carbonate and uranyl phosphate complexes. Analysis of more finely filtered samples (0.05 ??m vs. 0.45 ??m), and direct radiographic observations using fission-track detectors suspended in the waters indicate the presence of some uraniferous particulate matter. Application of existing thermodynamic data for uranous- and uranyl-bearing minerals indicates that all waters are undersaturated with U minerals as long as ambient Eh ??? +0.1 v. If coexisting surface and near-surface waters are sufficiently oxidizing, initial fixation of U in the deposit should be by a mechanism of adsorption. Alternatively, more reducing conditions may prevail in deeper pore waters of the organic-rich host sediments, perhaps leading to direct precipitation or diagenetic formation of U4+ minerals. A 234U 238U alpha activity ratio of 1.08 ?? 0.02 in a spring issuing from a hillslope above the deposit suggests a relatively soluble source of U. In contrast, higher activity ratios of 234U 238U (??? 1.3) in waters in contact with the uraniferous valley-fill sediments suggest differences in the nature of interaction between groundwater

  3. [Isolation and characterization of nitrogen-fixing bacteria of the genus Azospirillum from the soil of a Sphagnum peat bog].

    PubMed

    Doroshenko, E V; Bulygina, E S; Spiridonova, E M; Turova, T P; Kravchenko, I K

    2007-01-01

    The presence of nitrogen-fixing bacteria of the genus Azospirillum in the soils of acidic raised Sphagnum bogs is revealed for the first time. Three Azospirillum strains, B2, B21, and B22, were isolated as a component of methane-oxidizing enrichment cultures, whereas attempts to isolate them directly from peat samples have failed. The results of comparative analysis of the nucleotide sequences of 16S rRNA genes, DNA-DNA hybridization, and the analysis of the sequences of the functional genes encoding nitrogenase and ribulose-1, 5-bisphosphate carboxylase reveal that all the newly obtained strains can be classified as Azospirillum lipoferum. Yet, unlike A. lipoferum. the isolates do not require biotin and utilize sucrose, inositol, and glycerol for growth. The cell morphology of strain B2 differs from that of the type strain and strains B21 and B22. The results obtained indicate the variability of morphological, physiological, and biochemical properties in closely related Azospirillum strains and suggest the existence of metabolic relationships between methanotrophic bacteria and the representatives of the genus Azospirillum under peat bog conditions.

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

    NASA Astrophysics Data System (ADS)

    Jiménez-Moreno, Gonzalo; Anderson, R. Scott

    2012-01-01

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

  5. Contrasting wetland CH4 emission responses to simulated glacial atmospheric CO2 in temperate bogs and fens.

    PubMed

    Boardman, Carl P; Gauci, Vincent; Watson, Jonathan S; Blake, Stephen; Beerling, David J

    2011-12-01

    Wetlands were the largest source of atmospheric methane (CH(4) ) during the Last Glacial Maximum (LGM), but the sensitivity of this source to exceptionally low atmospheric CO(2) concentration ([CO(2) ]) at the time has not been examined experimentally. We tested the hypothesis that LGM atmospheric [CO(2) ] reduced CH(4) emissions as a consequence of decreased photosynthate allocation to the rhizosphere. We exposed minerotrophic fen and ombrotrophic bog peatland mesocosms to simulated LGM (c. 200 ppm) or ambient (c. 400 ppm) [CO(2) ] over 21 months (n = 8 per treatment) and measured gaseous CH(4) flux, pore water dissolved CH(4) and volatile fatty acid (VFA; an indicator of plant carbon supply to the rhizosphere) concentrations. Cumulative CH(4) flux from fen mesocosms was suppressed by 29% (P < 0.05) and rhizosphere pore water [CH(4) ] by c. 50% (P < 0.01) in the LGM [CO(2) ], variables that remained unaffected in bog mesocosms. VFA analysis indicated that changes in plant root exudates were not the driving mechanism behind these results. Our data suggest that the LGM [CO(2) ] suppression of wetland CH(4) emissions is contingent on trophic status. The heterogeneous response may be attributable to differences in species assemblage that influence the dominant CH(4) production pathway, rhizosphere supplemented photosynthesis and CH(4) oxidation.

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

    PubMed

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

    2014-11-04

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

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

    PubMed

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

    2010-04-01

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

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

    NASA Astrophysics Data System (ADS)

    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

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

    NASA Astrophysics Data System (ADS)

    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

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

    NASA Astrophysics Data System (ADS)

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

    2015-12-01

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

  11. Evidence for Multiple Holocene Marine Impact Events: Ejecta in a Bog Core

    NASA Astrophysics Data System (ADS)

    Abbott, D. H.; Courty, M.; Breger, D.; Costa, S.; Gerard-Little, P.; Burckle, L.; Pekar, S.

    2006-12-01

    In a core from Tamarack Pond (a former bog) in the Hudson Highlands of New York, we found two layers containing marine microfossils. Because carbon rich sediments can be bioturbated over 20 cm depths, we give the layer thicknesses as 20 cm. The first layer is at 332-354 cm depth. It contains a radiolarian with a splashed on coating of Fe-Cr-Ni metal. It also contains a benthonic foraminiferal fossil. The second layer is at 432-454 cm depth. The second layer contains a degraded radiolarian fossil, a silicate with a splashed on coating of Fe-Cr-Ni metal, a carbon rich spherule containing Fe-Cr-Ni metal, and a grain of titanomagnetite with multiple craters. It also contains organic matter with Sn in it. As Tamarack Pond is quite far from the ocean, the marine fossils in the cores are unlikely to be windblown debris of Holocene age. A benthonic foraminifera is particularly unlikely to be blown by the wind. This conclusion is strengthened by the observation that the splashed on coating of Fe-Cr-Ni metal occurs in chondritic relative abundances with Fe>Cr>Ni. In grains with a thick layer of splashed metal, the Ni is sufficiently abundant to produce 3 distinct Ni peaks in the X-ray analysis. Such a high abundance of Ni coupled with chondritic relative abundances suggests that the Fe-Cr- Ni splash is derived from the vaporization of an extraterrestrial impactor. If we assume that the sedimentation rate of the Tamarack Pond core is the same as that of a previously dated core from nearby Sutherland Pond, the two layers have an uncorrected C-14 age of around 900-1200 B.C. for the layer at 332-354 cm and 2100 to 2400 B.C. for the layer at 432-454 cm. Both ages have a rough correspondence with times of climate downturn recorded in tree ring data (1159 and 2354 B.C.). These climate downturns cannot be explained by volcanic eruptions and are proposed to be cosmogenic in origin[1]. The older layer also corresponds in components to a previously studied circa 2350 B.C. impact ejecta

  12. Atmospheric trace metal inputs in the Misten bog (East Belgium): Special attention to sampling techniques and site-spatial variability.

    NASA Astrophysics Data System (ADS)

    Allan, Mohammed; Fagel, Nathalie; de Vleeschouwer, François; Mattielli, Nadine; Piotrowska, Natalia; Sikorski, Jarek; Sonke, Jeroen E.; Le Roux, Gaël.

    2010-05-01

    Peat bogs have a great potential to record anthropogenic inputs via their constituting mosses, because they draw their nutrients only from the atmosphere. These atmospheric inputs can be studied thanks to geochemical characteristics such as trace metal concentrations. Coupling lead isotopes to elemental geochemistry allows one to decipher between natural (erosion of rocks) and anthropogenic (pollution due to industrial development, vehicles...) inputs. The purpose of our work was to study the pollution history of trace metals in the region of Misten (Belgium) at a local and a regional level, and to place modern industrial pollution in this region in a wider historical perspective. Four peat cores (01W, 04W, 05W and 06W) were collected in 2008 in the Misten bog (Hautes-Fagnes plateau, E-Belgium) and studied for their trace metal and lead isotopic signatures. Analyses were accompanied by coupled 210Pb-14C age models in order to estimate the mercury and lead accumulation rates in each core and compare them to other European records. The Hg record was compared to the various anthropogenic sources as determined by Pb isotopes. The Hg concentration profiles resemble those of Pb, an element known to be immobile in peatlands. The correlation between these two metals suggests a predominant anthropogenic source of Hg (and Pb). In the W06 core, low and stable Hg accumulation rates (0.9-3.1 μg m-2 yr-1) are found in the lower layers (503-1823AD). High Hg accumulation rates are found in the surface and sub-surface layers (post-1823AD) and peak at 123.3 μg m-2 yr-1 (1969AD). In 01W, the lead enrichment factor (Pb E.F.) coupled with the continuous drop in 206Pb/204Pb, 207Pb/204Pb, 208Pb/204Pb isotopic ratios since 539 AD until 1973AD indicates the growing importance of the non-radiogenic Pb released from anthropogenic activities. The highest concentrations of Pb (613-662 µg g-1) have been found near the surface of the bog dated between 1902 and 1954AD. The Pb E.F. also

  13. Uraniferous Phosphates: Resource, Security Risk, or Contaminant

    SciTech Connect

    LeMone, D.V.; Goodell, Ph.C.; Gibbs, S.G.; Winston, J.W.

    2008-07-01

    The escalation of the price of uranium (U) yellow cake (summer high = $130/0.454 kg (lb) has called into question the continuing availability of sufficient stockpiles and ores to process. As was developed during the years following World War II, the establishment and maintenance of a strategic inventory is a reasonable consideration for today. Therefore, it becomes critical to look at potential secondary resources beyond the classical ore suites now being utilized. The most economically viable future secondary source seems to be the byproducts of the beneficiation of phosphoric acids derived from phosphate ores. Phosphorous (P) is an essential nutrient for plants; its deficiency can result in highly restrictive limitations in crop productivity. Acidic soils in tropical and subtropical regions of the world are often P deficient with high P-sorption (fixation) capacities. To correct this deficiency, efficient water-soluble P fertilizers are required. The use of raw phosphate rocks not only adds phosphate but also its contained contaminants, including uranium to the treated land. Another immediate difficulty is phosphogypsum, the standard byproduct of simple extraction. It, for practical purposes, has been selectively classified as TENORM by regulators. The imposition of these standards presents major current and future disposal and re-utilization problems. Therefore, establishing an economically viable system that allows for uranium byproduct extraction from phosphoric acids is desirable. Such a system would be dependent on yellow cake base price stability, reserve estimates, political conditions, nation-state commitment, and dependence on nuclear energy. The accumulation of yellow cake from the additional extraction process provides a valuable commodity and allows the end acid to be a more environmentally acceptable product. The phosphogypsum already accumulated, as well as that which is in process, will not make a viable component for a radiation disposal devise (RDD). Concern for weapon proliferation by rogue nation states from the byproduct production of yellowcake is an unlikely scenario. To extract the fissile U-235 (0.07%) isotope from the yellowcake (99.3%) requires the erection of a costly major gaseous diffusion or a cascading centrifuge facility. Such a facility would be extremely difficult to mask. Therefore, from a diminished security risk and positive economic and environmental viewpoints, the utilization of a phosphoric acid beneficiation process extracting uranium is desirable. (authors)

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  15. Microbial community structure and activity linked to contrasting biogeochemical gradients in bog and fen environments of the Glacial Lake Agassiz Peatland.

    PubMed

    Lin, X; Green, S; Tfaily, M M; Prakash, O; Konstantinidis, K T; Corbett, J E; Chanton, J P; Cooper, W T; Kostka, J E

    2012-10-01

    The abundances, compositions, and activities of microbial communities were investigated at bog and fen sites in the Glacial Lake Agassiz Peatland of northwestern Minnesota. These sites contrast in the reactivity of dissolved organic matter (DOM) and the presence or absence of groundwater inputs. Microbial community composition was characterized using pyrosequencing and clone library construction of phylogenetic marker genes. Microbial distribution patterns were linked to pH, concentrations of dissolved organic carbon and nitrogen, C/N ratios, optical properties of DOM, and activities of laccase and peroxidase enzymes. Both bacterial and archaeal richness and rRNA gene abundance were >2 times higher on average in the fen than in the bog, in agreement with a higher pH, labile DOM content, and enhanced enzyme activities in the fen. Fungi were equivalent to an average of 1.4% of total prokaryotes in gene abundance assayed by quantitative PCR. Results revealed statistically distinct spatial patterns between bacterial and fungal communities. Fungal distribution did not covary with pH and DOM optical properties and was vertically stratified, with a prevalence of Ascomycota and Basidiomycota near the surface and much higher representation of Zygomycota in the subsurface. In contrast, bacterial community composition largely varied between environments, with the bog dominated by Acidobacteria (61% of total sequences), while the Firmicutes (52%) dominated in the fen. Acetoclastic Methanosarcinales showed a much higher relative abundance in the bog, in contrast to the dominance of diverse hydrogenotrophic methanogens in the fen. This is the first quantitative and compositional analysis of three microbial domains in peatlands and demonstrates that the microbial abundance, diversity, and activity parallel with the pronounced differences in environmental variables between bog and fen sites.

  16. Experimental warming delays autumn senescence in a boreal spruce bog: Initial results from the SPRUCE experiment

    NASA Astrophysics Data System (ADS)

    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

  17. Bacillus acidicola sp. nov., a novel mesophilic, acidophilic species isolated from acidic Sphagnum peat bogs in Wisconsin.

    PubMed

    Albert, Richard A; Archambault, Julieta; Rosselló-Mora, Ramón; Tindall, Brian J; Matheny, Mike

    2005-09-01

    A mesophilic, acidophilic, spore-forming bacterium, strain 105-2(T), was isolated from an acidic Sphagnum peat bog in Wisconsin, USA. Strain 105-2(T) has 16S rRNA gene sequence similarity to Bacillus sporothermodurans DSM 10599(T) and Bacillus oleronius DSM 9356(T) of 97.4 and 97.8%, respectively. The primary lipoquinone is MK-7 and the major fatty acids are 15:0 iso, 15:0 anteiso and 17:0 anteiso. The predominant polar lipids were found to be diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and a glycolipid. The DNA G+C content was found to be 43.2 mol%. The phenotypic, chemotaxonomic and molecular analyses identified strain 105-2(T) as a novel Bacillus species, for which the name Bacillus acidicola is proposed. The type strain is 105-2(T) (=DSM 14745(T)=ATCC BAA-366(T)=NRRL B-23453(T)).

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

    PubMed

    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.

  19. CH4 production via CO2 reduction in a temperate bog - A source of (C-13)-depleted CH4

    NASA Technical Reports Server (NTRS)

    Lansdown, J. M.; Quay, P. D.; King, S. L.

    1992-01-01

    The paper reports measurements, taken over two annual cycles, of the flux and delta(C-13) of CH4 released from an acidic peat bog located in the foothills of the Cascade Range in Washington state, U.S. Measurements of the rate of aceticlastic methanogenesis and CO2 reduction in peat soil, using (C-14)-labeled acetate and sodium bicarbonate, show that acetate was not an important CH4 precursor and that CO2 reduction could account for all of the CH4 production. The in situ kinetic isotope effect for CO2 reduction, calculated using the delta-(C-13) of soil water CO2 and CH4 flux, was 0.932 +/- 0.007.

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

    PubMed

    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.

  1. Are Bogs Reservoirs for Emerging Disease Vectors? Evaluation of Culicoides Populations in the Hautes Fagnes Nature Reserve (Belgium)

    PubMed Central

    Zimmer, Jean-Yves; Smeets, François; Simonon, Grégory; Fagot, Jean; Haubruge, Eric; Francis, Frédéric; Losson, Bertrand

    2013-01-01

    Several species of Culicoides (Diptera: Ceratopogonidae) biting midges serve as biological vectors for the bluetongue virus (BTV) and the recently described Schmallenberg virus (SBV) in northern Europe. Since their recent emergence in this part of the continent, these diseases have caused considerable economic losses to the sheep and cattle industries. Much data is now available that describe the distribution, population dynamics, and feeding habits of these insects. However, little is known regarding the presence of Culicoides in unusual habitats such as peaty marshes, nor their potential vector capacity. This study evaluated Culicoides biting midges present in the bogs of a Belgian nature reserve compared to those residing at a nearby cattle farm. Culicoides were trapped in 2011 at four different sites (broadleaved and coniferous forested areas, open environments, and at a scientific station) located in the Hautes Fagnes Nature Reserve (Belgium). An additional light trap was operated on a nearby cattle farm. Very high numbers of biting midges were captured in the marshy area and most of them (70 to 95%) were Culicoides impunctatus, a potential vector of BTV and other pathogens. In addition, fewer numbers of C. obsoletus/C. scoticus species, C. chiopterus, and C. dewulfi were observed in the bogs compared to the farm. The wet environment and oligotrophic nature of the soil were probably responsible for these changes in the respective populations. A total of 297,808 Culicoides midges belonging to 27 species were identified during this study and 3 of these species (C. sphagnumensis, C. clintoni and C. comosioculatus) were described in Belgium for the first time. PMID:23799137

  2. The spatial and temporal relationships between CO2 and CH4 exchange in a temperate ombrotrophic bog

    NASA Astrophysics Data System (ADS)

    Lai, Derrick Y. F.; Roulet, Nigel T.; Moore, Tim R.

    2014-06-01

    We investigate the relationships between CO2 and CH4 fluxes across space and time at a temperate ombrotrophic bog in Canada to assess the coupling between plant production and CH4 emissions. Based on periodic manual chamber measurements, we show that maximum net ecosystem CO2 exchange (NEEmax) was a good predictor of the spatial variations in CH4 flux among the wetter Eriophorum and lawn sites (r2 = 0.61-0.88), but not the drier hummock sites (r2 = 0.04-0.49). Also, we observed large interannual variability in the NEEmax-CH4 relationship at the Eriophorum and lawn sites, with a smaller regression slope in 2010 that had a seasonal mean water table 8 cm lower than in 2009. Results of cross-correlation of instantaneous gross ecosystem production (GEP) and CH4 flux from autochambers show a moderate relationship (σ = -0.31) in the Eriophorum community at a lag of 9-12 h, suggesting a rapid turnover of recent photosynthate for methanogenesis. On the other hand, we found in two Maianthemum-dominated chambers that the temperature-independent residuals of daily mean CH4 flux lagged behind GEP by 18-26 days at the seasonal scale. The lagged correlations between GEP and CH4 flux by month were particularly strong in the late growing season in the Eriophorum and Maianthemum/Ledum communities. Our results suggest the presence of spatial and temporal coupling of plant production and CH4 emissions in this bog, whose strength varies with species composition, water table position, and plant phenology.

  3. Are bogs reservoirs for emerging disease vectors? Evaluation of culicoides populations in the Hautes Fagnes Nature Reserve (Belgium).

    PubMed

    Zimmer, Jean-Yves; Smeets, François; Simonon, Grégory; Fagot, Jean; Haubruge, Eric; Francis, Frédéric; Losson, Bertrand

    2013-01-01

    Several species of Culicoides (Diptera: Ceratopogonidae) biting midges serve as biological vectors for the bluetongue virus (BTV) and the recently described Schmallenberg virus (SBV) in northern Europe. Since their recent emergence in this part of the continent, these diseases have caused considerable economic losses to the sheep and cattle industries. Much data is now available that describe the distribution, population dynamics, and feeding habits of these insects. However, little is known regarding the presence of Culicoides in unusual habitats such as peaty marshes, nor their potential vector capacity. This study evaluated Culicoides biting midges present in the bogs of a Belgian nature reserve compared to those residing at a nearby cattle farm. Culicoides were trapped in 2011 at four different sites (broadleaved and coniferous forested areas, open environments, and at a scientific station) located in the Hautes Fagnes Nature Reserve (Belgium). An additional light trap was operated on a nearby cattle farm. Very high numbers of biting midges were captured in the marshy area and most of them (70 to 95%) were Culicoides impunctatus, a potential vector of BTV and other pathogens. In addition, fewer numbers of C. obsoletus/C. scoticus species, C. chiopterus, and C. dewulfi were observed in the bogs compared to the farm. The wet environment and oligotrophic nature of the soil were probably responsible for these changes in the respective populations. A total of 297,808 Culicoides midges belonging to 27 species were identified during this study and 3 of these species (C. sphagnumensis, C. clintoni and C. comosioculatus) were described in Belgium for the first time.

  4. Diversity and community structure of Archaea inhabiting the rhizoplane of two contrasting plants from an acidic bog.

    PubMed

    Cadillo-Quiroz, Hinsby; Yavitt, Joseph B; Zinder, Stephen H; Thies, Janice E

    2010-05-01

    Plant root exudates increase nutrient availability and influence microbial communities including archaeal members. We examined the archaeal community inhabiting the rhizoplane of two contrasting vascular plants, Dulichium arundinaceum and Sarracenia purpurea, from an acidic bog in upstate NY. Multiple archaeal 16S rRNA gene libraries showed that methanogenic Archaea were dominant in the rhizoplane of both plants. In addition, the community structure (evenness) of the rhizoplane was found markedly different from the bulk peat. The archaeal community in peat from the same site has been found dominated by the E2 group, meanwhile the rhizoplane communities on both plants were co-dominated by Methanosarcinaceae (MS), rice cluster (RC)-I, and E2. Complementary T-RFLP analysis confirmed the difference between bulk peat and rhizoplane, and further characterized the dominance pattern of MS, RC-I, and E2. In the rhizoplane, MS was dominant on both plants although as a less variable fraction in S. purpurea. RC-I was significantly more abundant than E2 on S. purpurea, while the opposite was observed on D. arundinaceum, suggesting a plant-specific enrichment. Also, the statistical analyses of T-RFLP data showed that although both plants overlap in their community structure, factors such as plant type, patch location, and time could explain nearly a third of the variability in the dataset. Other factors such as water table, plant replicate, and root depth had a low contribution to the observed variance. The results of this study illustrate the general effects of roots and the specific effects of plant types on their nearby archaeal communities which in bog-inhabiting plants were mainly composed by methanogenic groups.

  5. How well do environmental archives of atmospheric mercury deposition in the Arctic reproduce rates and trends depicted by atmospheric models and measurements?

    PubMed

    Goodsite, M E; Outridge, P M; Christensen, J H; Dastoor, A; Muir, D; Travnikov, O; Wilson, S

    2013-05-01

    This review compares the reconstruction of atmospheric Hg deposition rates and historical trends over recent decades in the Arctic, inferred from Hg profiles in natural archives such as lake and marine sediments, peat bogs and glacial firn (permanent snowpack), against those predicted by three state-of-the-art atmospheric models based on global Hg emission inventories from 1990 onwards. Model veracity was first tested against atmospheric Hg measurements. Most of the natural archive and atmospheric data came from the Canadian-Greenland sectors of the Arctic, whereas spatial coverage was poor in other regions. In general, for the Canadian-Greenland Arctic, models provided good agreement with atmospheric gaseous elemental Hg (GEM) concentrations and trends measured instrumentally. However, there are few instrumented deposition data with which to test the model estimates of Hg deposition, and these data suggest models over-estimated deposition fluxes under Arctic conditions. Reconstructed GEM data from glacial firn on Greenland Summit showed the best agreement with the known decline in global Hg emissions after about 1980, and were corroborated by archived aerosol filter data from Resolute, Nunavut. The relatively stable or slowly declining firn and model GEM trends after 1990 were also corroborated by real-time instrument measurements at Alert, Nunavut, after 1995. However, Hg fluxes and trends in northern Canadian lake sediments and a southern Greenland peat bog did not exhibit good agreement with model predictions of atmospheric deposition since 1990, the Greenland firn GEM record, direct GEM measurements, or trends in global emissions since 1980. Various explanations are proposed to account for these discrepancies between atmosphere and archives, including problems with the accuracy of archive chronologies, climate-driven changes in Hg transfer rates from air to catchments, waters and subsequently into sediments, and post-depositional diagenesis in peat bogs

  6. Nutrient stoichiometry in Sphagnum along a nitrogen deposition gradient in highly polluted region of Central-East Europe.

    PubMed

    Jiroušek, Martin; Hájek, Michal; Bragazza, Luca

    2011-02-01

    We investigated the variation of N:P and N:K ratio in ombrotrophic Sphagnum plants along a gradient of atmospheric N deposition from 1 to 2.5 g m(-2) year(-1) in Central-East Europe. The N:P and N:K ratio in Sphagnum capitula increased significantly along the N deposition gradient. Sphagnum species from the Cuspidata section were characterised by significantly lower ratios at low N deposition. When we compared the observed N:P ratios in Sphagnum plants with the values reported in a previous European-wide study, we found a correspondence in nutrient stoichiometry only for a few bogs: higher P concentration in Sphagnum capitula caused a lower N:P ratio in most of the study bogs so that Sphagnum plants still seem N-limited despite their N saturation. Interaction between summer water table decrease and aerial liming of surrounding forests is proposed as an explanation for this discrepancy. Local forestry practice interacting with climate thus alter N:P stoichiometry of Sphagnum along the N deposition gradient.

  7. Nitrogen deposition and prey nitrogen uptake control the nutrition of the carnivorous plant Drosera rotundifolia.

    PubMed

    Millett, J; Foot, G W; Svensson, B M

    2015-04-15

    Nitrogen (N) deposition has important negative impacts on natural and semi-natural ecosystems, impacting on biotic interactions across trophic levels. Low-nutrient systems are particularly sensitive to changes in N inputs and are therefore more vulnerable to N deposition. Carnivorous plants are often part of these ecosystems partly because of the additional nutrients obtained from prey. We studied the impact of N deposition on the nutrition of the carnivorous plant Drosera rotundifolia growing on 16 ombrotrophic bogs across Europe. We measured tissue N, phosphorus (P) and potassium (K) concentrations and prey and root N uptake using a natural abundance stable isotope approach. Our aim was to test the impact of N deposition on D. rotundifolia prey and root N uptake, and nutrient stoichiometry. D. rotundifolia root N uptake was strongly affected by N deposition, possibly resulting in reduced N limitation. The contribution of prey N to the N contained in D. rotundifolia ranged from 20 to 60%. N deposition reduced the maximum amount of N derived from prey, but this varied below this maximum. D. rotundifolia tissue N concentrations were a product of both root N availability and prey N uptake. Increased prey N uptake was correlated with increased tissue P concentrations indicating uptake of P from prey. N deposition therefore reduced the strength of a carnivorous plant-prey interaction, resulting in a reduction in nutrient transfer between trophic levels. We suggest that N deposition has a negative impact on D. rotundifolia and that responses to N deposition might be strongly site specific.

  8. Multi-scale hydroclimate reconstruction using co-located lake and bog records from Maine and comparison with other records from the Northeast US

    NASA Astrophysics Data System (ADS)

    Nolan, C.; Shuman, B. N.; Booth, R.; Jackson, S. T.

    2015-12-01

    Sedimentary lake-level records and ombrotrophic bog water-table depth records both document hydrologic variability over the Holocene. Lake level records have long temporal length (10,000+ years) and fidelity in preserving low-frequency trends and centennial to millennial length events. Hydrologic reconstructions based on peatland testate amoebae assemblage composition are sensitive to moisture variability at interannual to multidecadal time scales and precipitation on the bog surface is the sole moisture input. However, bog records are generally not as long as lake level records and bog development processes can confound centennial to millennial trends. In this study we present and combine new reconstructions from Giles Pond, Aurora, Maine, USA and Caribou Bog, Old Town, ME USA. The lake-level record from Giles Pond extends a network of lake-level records from southern New England that show an orbitally driven long-term trend toward wetter conditions punctuated by low-water phases in the mid- to late-Holocene that each lasted 100 to 400+ years. Some of these low lake level events appear to be synchronous across multiple sites in New England (Newby, et al. 2014 GRL). Preliminary data from Giles Pond suggest that some of these events extended all the way to Maine. Thus, there were New England-wide dry periods within the last 5000 years that lasted more than 100 years. These long low stands are unlike anything observed during the historical period and the interannual to decadal variability during these low stands is poorly understood. This leads to challenges in understanding the modern and future implications of the lake-level record alone. The Caribou Bog record also builds on a network of peatland water-table reconstructions from the Northeast, and contributes higher-resolution hydroclimate information that adds interannual to multidecadal texture to the centennial to millennial variability of the Giles Pond record. Our multiproxy approach allows us to use the

  9. Biochemical processes of oligotrophic peat deposits of Vasyugan Mire

    NASA Astrophysics Data System (ADS)

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

    2009-04-01

    The problem of peat and mire ecosystems functioning and their rational use is the main problem of biosphere study. This problem also refers to forecasting of biosphere changes results which are global and anthropogenic. According to many scientists' research the portion of mires in earth carbon balance is about 15% of world's stock. The aim of this study is to investigate biochemical processes in oligotrophic deposits in North-eastern part of Vasyugan Mire. The investigations were made on the territory of scientific-research ground (56˚ 03´ and 56˚ 57´ NL, 82˚ 22´ and 82˚ 42´ EL). It is situated between two rivers Bakchar and Iksa (in outskirts of the village Polynyanka, Bakchar region, Tomsk oblast). Evolution of investigated mire massif began with the domination of eutrophic phytocenosis - Filicinae, then sedge. Later transfer into oligotrophic phase was accompanied by formation of meter high-moor peat deposit. The age of three-meter peat deposit reaches four thousand years. Biochemical processes of carbon cycle cover the whole peat deposit, but the process activity and its direction in different layers are defined by genesis and duration of peat formation. So, the number of cellulose-fermenting aerobes in researched peat deposits ranges from 16.8 to 75.5 million CFU/g, and anaerobic bacteria from 9.6 to 48.6 million CFU/g. The high number of aerobes is characteristic for high water levels, organizing by raised bog peats. Their number decreases along the profile in 1.7 - 2 times. The number of microflora in peat deposit is defined by the position in the landscape profile (different geneses), by the depth, by hydrothermic conditions of years and individual months. But microflora activity shows along all depth of peat deposit. We found the same in the process of studying of micromycete complex structure. There was revealed either active component micromycete complex - mycelium, or inert one - spores in a meter layer of peat deposit. If mushrooms

  10. Health assessment for Burnt Fly Bog National Priorities List Site, Marlboro, Monmouth County, New Jersey, Region 2. CERCLIS No. NJD980504997. Final report

    SciTech Connect

    Not Available

    1988-08-24

    The Burnt Fly Bog site, a National Priorities List site, is located near Marlboro, Monmouth County, New Jersey in the fringe area of the New Jersey Pine Barrens. The major contaminants at the site are polychlorinated biphenyls (PCBs) and lead. Both of these contaminants have been found in all environmental media at the site. Exposure to contaminants may occur from contact with soil, sediment, water, air, or biota from the site. In order to protect the public health, access to contaminated areas should not be permitted except for properly-protected remedial workers. Because of the potential for ground-water contamination, private well owners surrounding the site should be advised to connect to the public water system. In addition, the consumption of game animals, berries, fish, and other biota from Burnt Fly Bog should be discouraged unless it can be determined that they are free of contamination.

  11. [Genetic variation and differentiation of peat-bog and dry-meadow populations of the dwarf mountain pine Pinus mugo Turra in the highlands of the Ukrainian Carpathians].

    PubMed

    Korshikov, I I; Pirko, Ia V

    2002-09-01

    Based on electrophoretic analysis of 21 isozyme loci controlling 10 enzyme systems, the intra- and inter-population variation was studied in two peat-bog and three dry-meadow populations of the dwarf mountain pine Pinus mugo Turra from the highlands of the Ukrainian Carpathians. In the studied samples (a total of 164 trees), on average 62% of the studied genes were polymorphic; the mean heterozygosity was 21.3%. The dry-meadow populations differed from the peat-bog populations by allele and genotype diversity and by heterozygosity although the indices characterizing population heterogeneity (Fst and Gst) were small (0.027 and 0.032, respectively). Nei's genetic distances between the populations ranged of 0.011 to 0.032 with the mean of 0.018.

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

    NASA Astrophysics Data System (ADS)

    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

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

    NASA Astrophysics Data System (ADS)

    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

  14. Dissolved carbon and nitrogen quantity and quality at natural, drained and re-wetted bog sites in Lower Saxony (Germany)

    NASA Astrophysics Data System (ADS)

    Frank, Stefan; Tiemeyer, Bärbel; Freibauer, Annette

    2013-04-01

    5 % of Germany's land area is covered with peatlands. Due to the large carbon and nitrogen stocks, changes in peatland hydrology for agricultural use have a huge impact on C and N cycling in the peatland and on the export to the atmosphere and adjacent ecosystems. Nonetheless, only a few studies focussed on the impact of drainage and re-wetting on C and N cycling in German raised bogs. Four study sites in the "Ahlenmoor" near Cuxhaven (Northwestern Germany) were chosen. This bog has a deep, medium to weakly decomposed peat layer. The sites represent a gradient of the groundwater level combined with land use differences (intensive and extensive grassland, natural site, re-wetted peat-cutting area). The mean annual groundwater level decreases from the natural and re-wetted sites (near surface) to the extensive grassland (30 cm below surface) and, finally, the intensive grassland (56 cm). The "Peeper" technique (dialysis sampler) was used to measure soil water chemistry in a high spatial resolution. At each site, three peepers (0-60 cm, 12 chambers each) collected soil water samples via diffusion. Monthly sampling was conducted from February 2012 till November 2012. The soil water solution was analysed for pH, EC, dissolved organic carbon (DOC), dissolved organic nitrogen (DON), NH4+, NO3- and SUVA(280). Samples taken in November 2012 were additionally analysed for dissolved CO2, CH4 and N2O. Average DOC concentrations ranged from 211 to 41 mg/L and decreased in order intensive > extensive grassland > re-wetted = natural site. After 10 years of restoration, the re-wetted and the natural site show similar DOC concentrations. Average SUVA(280) values of 3.7 to 3.3 L/(mg m) were higher at the grassland sites than at the re-wetted and the natural site. This indicates a distinct increase in aromaticity of DOC in grassland sites as a result of more intense humification of the upper peat layer. In contrast to mineral soils, SUVA(280) remained constant with depth at our sites

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

    NASA Astrophysics Data System (ADS)

    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.

  16. Holocene vegetation and climate change in southern New Zealand: linkages between forest composition and quantitative surface moisture reconstructions from an ombrogenous bog

    NASA Astrophysics Data System (ADS)

    Wilmshurst, Janet M.; McGlone, Matt S.; Charman, Dan J.

    2002-10-01

    This paper presents a Holocene pollen record from an ombrotrophic bog in Southland, New Zealand, together with multiproxy data (testate amoebae, peat humification and plant macrofossils) from the same core to establish an independent semiquantitative record of peatland surface moisture. Linkages between reconstructed peatland surface moisture and regional forest composition are investigated using redundancy analysis of the forest pollen data constrained with predicted bog water-table depths. Over 32% of the pollen data variance can be explained by surface moisture changes in the bog, suggesting a common cause of water-table and regional vegetation change. Water tables were higher during the early to mid-Holocene when the forest was dominated by podocarp taxa. Water tables lowered after about 3300 cal. yr BP coevally with the expansion of Nothofagus species, culminating with the dominance of Nothofagus subgenus Fuscospora in the past 1200 cal. yr BP. This is in apparent opposition to the warm/dry to cool/wet trend suggested by subjective interpretation of pollen data alone, from this and other studies. We suggest that during the late Holocene, drier summers associated with shifts in solar insolation caused reduced surface wetness and summer humidity, which together with a trend to cooler winters, apparently favoured the regeneration of Nothofagus species.

  17. Effects of short-term drying and irrigation on electron flow in mesocosms of a northern bog and an alpine fen.

    PubMed

    Deppe, Marianna; McKnight, Diane M; Blodau, Christian

    2010-01-01

    Methane emissions and element mobility in wetlands are controlled by soil moisture and redox conditions. We manipulated soil moisture by weekly drying and irrigation of mesocosms of peat from a bog and iron and sulfur rich fen. Water table changed more strongly in the decomposed fen peat ( approximately 11 cm) than in the fibric bog peat ( approximately 5 cm), where impacts on redox processes were larger due to larger change in air filled porosity. Methanogenesis was partly decoupled from acetogenesis and acetate accumulated up to 5.6 mmol L(-1) in the fen peat after sulfate was depleted. Irrigation and drying led to rapid redox-cycles with sulfate, hydrogen sulfide, nitrate, and methane being produced and consumed on the scale of days, contributing substantially to the total electron flow and suggesting short-term resilience of the microbial community to intermittent aeration. Anaerobic CO2 production was partly balanced by methanogenesis (0-34%), acetate fermentation (0-86%), and sulfate reduction (1-30%) in the bog peat. In the fen peat unknown electron acceptors and aerenchymatic oxygen influx apparently drove respiration. The results suggest that regular rainfall and subsequent drying may lead to local oxidation-reduction cycles that substantially influence electron flow in electron acceptor poor wetlands.

  18. Peat bogs offer a reliable, local source of fuel in several states

    SciTech Connect

    Punwani, D.V.

    1981-10-01

    With total estimated US peat resources equivalent to the energy content of 240-billion bbl of oil, peat could be a significant energy resource even if only a fraction of it can be recovered. Resource estimates include only those areas (mostly in eight states) with at least 80 acres/sq mi of peat, where the deposits are at least 4 ft deep. Peat fuel properties, new equipment for peat harvesting and dewatering, and modern combustion technology are described. Conversion to synthetic fuels looks promising.

  19. Application of paleoDNA for identification of paleotsunami deposits

    NASA Astrophysics Data System (ADS)

    Szczucinski, W.; Pawlowska, J.; Lejzerowicz, F.; Nishimura, Y.; Kokocinski, M.; Majewski, W.; Nakamura, Y.; Pawlowski, J.

    2015-12-01

    The identification of sedimentary records of paleotsunamis is the key to tsunami hazard assessment. However, it is often challenging to distinguish the tsunami deposits due to their variability, influence of local context, variable sediment sources, as well as postdepositional alterations. Among the most commonly used approaches to identify paleotsunami is the study of microfossils (e.g. foraminifera, diatoms). They are most commonly used to show marine origin of sediments. The common problem with microfossils in coastal settings (eg. marshes, peat bogs) is that they may not be preserved. For instance, it was found during studies on post-depositional changes of 2004 tsunami deposits and in paleotsunami deposits in Thailand that the tests composed of calcium carbonate as well as from silica have been largely dissolved with time. The rapid progress in paleogenetic studies suggests that analyses of DNA preserved in marine sediments may be a new research direction. A recent successful application of the method to the deep sea and fjord sediments, greater than 30,000 years old proved that it is possible to extract DNA and identify it from sediments that are affected by oxygenated waters and bioturbating organisms. Here we apply the paleogenetic studies for a series of paleotsunami deposits from Urahoro, eastern Hokkaido Island, Japan dated to be from several hundreds of years to more than 2000 years old based on tephrochronology. The sandy tsunami deposits intercalated by muddy peat contained rare diatoms of various origin but foraminifera and radiolaria tests were missing. Nevertheless, we were able to retrieve short fragments of the foraminiferal DNA from marine species using high-throughput sequencing technology. Our study provides first evidence that eukaryotic DNA can be preserved in tsunami deposits in coastal marsh environment for as long as 2000 years even in absence of any micropaleontological evidence. Thus paleoDNA analyses may provide a new useful tool to

  20. Isolation and identification of methanogen-specific DNA from blanket bog peat by PCR amplification and sequence analysis.

    PubMed

    Hales, B A; Edwards, C; Ritchie, D A; Hall, G; Pickup, R W; Saunders, J R

    1996-02-01

    The presence of methanogenic bacteria was assessed in peat and soil cores taken from upland moors. The sampling area was largely covered by blanket bog peat together with small areas of red-brown limestone and peaty gley. A 30-cm-deep core of each soil type was taken, and DNA was extracted from 5-cm transverse sections. Purified DNA was subjected to PCR amplification with primers IAf and 1100Ar, which specifically amplify 1.1 kb of the archaeal 16S rRNA gene, and ME1 and ME2, which were designed to amplify a 0.75-kb region of the alpha-subunit gene for methyl coenzyme M reductase (MCR). Amplification with both primer pairs was obtained only with DNA extracted from the two deepest sections of the blanket bog peat core. This is consistent with the notion that anaerobiosis is required for activity and survival of the methanogen population. PCR products from both amplifications were cloned, and the resulting transformants were screened with specific oligonucleotide probes internal to the MCR or archaeal 16S rRNA PCR product. Plasmid DNA was extracted from probe-positive clones of both types and the insert was sequenced. The DNA sequences of 8 MCR clones were identical, as were those of 16 of the 17 16S rRNA clones. One clone showed marked variation from the remainder in specific regions of the sequence. From a comparison of these two different 16S rRNA sequences, an oligonucleotide was synthesized that was 100% homologous to a sequence region of the first 16 clones but had six mismatches with the variant. This probe was used to screen primary populations of PCR clones, and all of those that were probe negative were checked for the presence of inserts, which were then sequenced. By using this strategy, further novel methanogen 16S rRNA variants were identified and analyzed. The sequences recovered from the peat formed two clusters on the end of long branches within the methanogen radiation that are distinct from each other. These cannot be placed directly with sequences

  1. Carbon dioxide fluxes over a raised open bog at the Kinosheo Lake tower site during the Northern Wetlands Study (NOWES)

    NASA Technical Reports Server (NTRS)

    Neumann, H. H.; Den Hartog, G.; King, K. M.; Chipanshi, A. C.

    1994-01-01

    Measurements of carbon dioxide concentration and flux were made above a raised open bog at Lake Kinosheo in the southern Hudson Bay lowlands during the Northern Wetlands Study (NOWES) experiment in 1990. The flux measurements were made using micrometeorological techniques. They provide the first nondisturbing, larger-scale CO2 flux measurements for this ecosystem and are the first to integrate the exchange over the whole 24 hours of the day. Continuous concentration measurements by infrared gas analyzers (IRGA) and spot flask samples were taken over the period July 1 to July 29. Afternoon CO2 values were only 5 to 7 parts per million by volume (ppmv) lower than measurements over the same period at Canadian background monitoring stations. This suggested that there was little draw-down by local photosynthetic sinks. CO2 fluxes were measured at 8 and 18 m by Bowen ratio and eddy correlation methods, respectively. The methods produced comparable results on averaged data but often diverged considerably on individual half-hour results. Fluxes were small. Daytime values averaged to -0.068 mg/sq m/s by eddy correlation and -0.077 mg/sq m/s by Bowen ratio over the period June 25 to July 28 (negative denotes downward flux), while at night, flux densities were +0.062 mg/sq m/s and +0.085 mg/sq m/s. Integration of the mean diurnal curve gave a net flux of -1.7 g/sq m/d. Comparable data for this type of ecosystem were not found. However, Coyne and Kelley (1975), measuring near Barrow, Alaska, over wet meadow tundra dominated by sedges and grasses, found net fluxes of -7.2 g/sq m/d. Typical net CO2 fluxes from other active temperature ecosystems have been found to be -10 to -20 g/sq m/d (Monteith, 1976). Mean half hourly fluxes were almost constant at +0.06 mg/sq m/s through the nighttime hours. About one half-hour after sunrise the flux reversed direction. Uptake peaked about 0900 eastern daylight time (EDT) and then gradually declined but remained downward until near sunset

  2. Elevated Nitrogen Deposition from Alberta Oil Sands Development Stimulates Phosphatase Activity in Dominant Sphagnum Moss Species

    NASA Astrophysics Data System (ADS)

    Kashi, N. N.; Wieder, R.; Vile, M. A.

    2013-12-01

    Emissions of NOx associated with Alberta oil sands (AOS) development are leading to locally elevated atmospheric N deposition, in a region where background N deposition has been historically quite low (< 1 kg/ha/yr). This elevated N deposition has the potential to alter the ecosystem structure and function of nutrient-poor boreal peatlands. Nitrogen enrichment may alter soil microbial activity, which could be manifested in changes in extracellular enzyme activities. Since 2011, we have been experimentally adding N as NH4NO3 in simulated precipitation at 0, 5, 10, 15, 20, and 25 kg N ha/yr/ plus no-water controls to a boreal bog and a poor fen (3 replicate plots per treatment). In 2013, acid phosphatase activities in living plant capitulum of Sphagnum angustifolium, Sphagnum fuscum, and Sphagnum magellanicum were quantified in June and July using 4-methyumbelliferylphosphate and fluorescence detection of the enzymatically released methylumbelliferone (MUF). Phosphatase activities did not differ with N treatment for S. angustifolium in the bog (p=0.3409) or the poor fen (p=0.0629), or for S. fuscum in the bog (p=0.1950), averaging 35.0 × 0.7, 61.6 × 1.2, and 41.6 × 0.9 μmol MUF/g DWT/hr, respectively. For S. fuscum in the poor fen, phosphatase activities differed between N treatments (p=0.0275), ranging 40.6 × 1.1 μmol MUF/g DWT/hr in the control plots to 73.7 × 2.0 μmol MUF/g DWT/hr in the 5 kg/ha/yr N treatment plots; increasing N deposition did not result in a gradual change in enzyme activity. On the other hand, S. magellanicum phosphatase activities differed between N treatments (p=0.0189) and showed a pattern of generally increasing activity with increasing N deposition (37.4 × 0.5 μmol MUF/g DWT/hr in control plots; 97.9 × 4.5 μmol MUF/g DWT/hr in the 25 kg/ha/yr N treatment plots). The differing phosphatase responses between these dominant Sphagnum species suggest unique differences in nutrient balance and/or microbial activity. Combining the

  3. Evidence for differential effects of reduced and oxidised nitrogen deposition on vegetation independent of nitrogen load.

    PubMed

    van den Berg, Leon J L; Jones, Laurence; Sheppard, Lucy J; Smart, Simon M; Bobbink, Roland; Dise, Nancy B; Ashmore, Mike R

    2016-01-01

    Nitrogen (N) deposition impacts natural and semi-natural ecosystems globally. The responses of vegetation to N deposition may, however, differ strongly between habitats and may be mediated by the form of N. Although much attention has been focused on the impact of total N deposition, the effects of reduced and oxidised N, independent of the total N deposition, have received less attention. In this paper, we present new analyses of national monitoring data in the UK to provide an extensive evaluation of whether there are differences in the effects of reduced and oxidised N deposition across eight habitat types (acid, calcareous and mesotrophic grasslands, upland and lowland heaths, bogs and mires, base-rich mires, woodlands). We analysed data from 6860 plots in the British Countryside Survey 2007 for effects of total N deposition and N form on species richness, Ellenberg N values and grass:forb ratio. Our results provide clear evidence that N deposition affects species richness in all habitats except base-rich mires, after factoring out correlated explanatory variables (climate and sulphur deposition). In addition, the form of N in deposition appears important for the biodiversity of grasslands and woodlands but not mires and heaths. Ellenberg N increased more in relation to NHx deposition than NOy deposition in all but one habitat type. Relationships between species richness and N form were habitat-specific: acid and mesotrophic grasslands appear more sensitive to NHx deposition while calcareous grasslands and woodlands appeared more responsive to NOy deposition. These relationships are likely driven by the preferences of the component plant species for oxidised or reduced forms of N, rather than by soil acidification.

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

    NASA Astrophysics Data System (ADS)

    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

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

    NASA Astrophysics Data System (ADS)

    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

  6. Heatwave 2003: high summer temperature, rather than experimental fertilization, affects vegetation and CO2 exchange in an alpine bog.

    PubMed

    Gerdol, Renato; Bragazza, Luca; Brancaleoni, Lisa

    2008-01-01

    Nitrogen and phosphorus were added experimentally in a bog in the southern Alps. It was hypothesized that alleviating nutrient limitation will increase vascular plant cover. As a consequence, more carbon will be fixed through higher rates of net ecosystem CO(2) exchange (NEE). The vascular cover did increase at the expense of Sphagnum mosses. However, such vegetation changes were largely independent of the treatment and were probably triggered by an exceptional heatwave in summer 2003. Contrary to the tested hypothesis, NEE was unaffected by the nutrient treatments but was strongly influenced by temperature and water-table depth. In particular, ecosystem respiration in the hot summer of 2003 increased dramatically, presumably owing to enhanced heterotrophic respiration in an increased oxic peat layer. At the end of the experiment, the Sphagnum cover decreased significantly in the nitrogen-fertilized treatment at hummock microhabitats. In the long term, this will imply a proportionally greater accumulation of vascular litter, more easily decomposable than the recalcitrant Sphagnum litter. As a result, rates of carbon fixation may decrease because of stimulated respiration.

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

    PubMed Central

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

    2015-01-01

    Sphagnum bog ecosystems are among the oldest vegetation forms harboring a specific microbial community and are known to produce an exceptionally wide variety of bioactive substances. Although the Sphagnum metagenome shows a rich secondary metabolism, the genes have not yet been explored. To analyze nonribosomal peptide synthetases (NRPSs) and polyketide synthases (PKSs), the diversity of NRPS and PKS genes in Sphagnum-associated metagenomes was investigated by in silico data mining and sequence-based screening (PCR amplification of 9,500 fosmid clones). The in silico Illumina-based metagenomic approach resulted in the identification of 279 NRPSs and 346 PKSs, as well as 40 PKS-NRPS hybrid gene sequences. The occurrence of NRPS sequences was strongly dominated by the members of the Protebacteria phylum, especially by species of the Burkholderia genus, while PKS sequences were mainly affiliated with Actinobacteria. Thirteen novel NRPS-related sequences were identified by PCR amplification screening, displaying amino acid identities of 48% to 91% to annotated sequences of members of the phyla Proteobacteria, Actinobacteria, and Cyanobacteria. Some of the identified metagenomic clones showed the closest similarity to peptide synthases from Burkholderia or Lysobacter, which are emerging bacterial sources of as-yet-undescribed bioactive metabolites. This report highlights the role of the extreme natural ecosystems as a promising source for detection of secondary compounds and enzymes, serving as a source for biotechnological applications. PMID:26002894

  8. Three new species of oribatid mites of the family Punctoribatidae (Acari, Oribatida) from alpine bogs of New Zealand.

    PubMed

    Ermilov, Sergey G; Minor, Maria A

    2016-03-15

    Three new species of oribatid mites of the family Punctoribatidae (Acari, Oribatida) are described from alpine bogs of the Central Otago region in the South Island of New Zealand. Macrogena hexasetosa sp. nov. is morphologically most similar to M. brevisensilla Ermilov & Minor, 2015, however, it differs from the latter by larger body size, the presence of six pairs of genital setae, notogastral and ano-adanal setae of medium size, setiform rostral setae, narrower tutorial cusps, the absence of antero-ventral teeth on genua I, II and femora II, and by the absence of striae on the subcapitular mentum. Porallozetes badamdorji sp. nov. differs from the type species-P. dispar (Hammer, 1973)-by larger body length, the presence of interlamellar setae, short and clavate bothridial setae, anterior notogastral margin, notogastral setae of medium size, semi-oval dorsophragmata, and by the position of notogastral porose areas A2 posteriorly to A1. Safrobates gerdi sp. nov. differs from the type species-S. miniporus Mahunka, 1989-by larger body size, the presence of setiform rostral setae, and by notogastral setae of medium length. Porallozetes and Safrobates are recorded in New Zealand for the first time. Generic diagnoses for Macrogena, Porallozetes and Safrobates are given.

  9. Chromobacterium vaccinii sp. nov., isolated from native and cultivated cranberry (Vaccinium macrocarpon Ait.) bogs and irrigation ponds.

    PubMed

    Soby, Scott D; Gadagkar, Sudhindra R; Contreras, Cristina; Caruso, Frank L

    2013-05-01

    A large number of Gram-negative, motile, mesophilic, violacein-producing bacteria were isolated from the soils and roots of Vaccinium macrocarpon Ait. and Kalmia angustifolia L. plants and from irrigation ponds associated with wild and cultivated cranberry bogs in Massachusetts, USA. Phylogenetic analyses of 16S rRNA gene sequences placed these isolates in a clade with Chromobacterium species, but the specialized environment from which they were isolated, their low genomic DNA relatedness with Chromobacterium violaceum ATCC 12472(T) and C. subtsugae PRAA4-1(T), significant differences in fatty acid composition and colony morphology indicate that the cranberry and Kalmia isolates comprise a separate species of Chromobacterium, for which the name Chromobacterium vaccinii sp. nov. is proposed. Strain MWU205(T) ( = ATCC BAA-2314(T)  = DSM 25150(T)) is proposed as the type strain for the novel species. Phenotypic analysis of 26 independent isolates of C. vaccinii sp. nov. indicates that, despite close geographical and biological proximity, there is considerable metabolic diversity among individuals within the population.

  10. History and environmental impact of mining activity in Celtic Aeduan territory recorded in a peat bog (Morvan, France).

    PubMed

    Monna, F; Petit, C; Guillaumet, J P; Jouffroy-Bapicot, I; Blanchot, C; Dominik, J; Losno, R; Richard, H; Lévêque, J; Chateau, C

    2004-02-01

    The present study aims to document historical mining and smelting activities by means of geochemical and pollen analyses performed in a peat bog core collected around the Bibracte oppidum (Morvan, France), the largest settlement of the great Aeduan Celtic tribe (ca. 180 B.C. to 25 A.D.). The anthropogenic Pb profile indicates local mining operations starting from the Late Bronze Age, ca. cal. 1300 B.C. Lead inputs peaked at the height of Aeduan civilization and then decreased after the Roman conquest of Gaul, when the site was abandoned. Other phases of mining are recognized from the 11th century to modern times. They have all led to modifications in plant cover, probably related in part to forest clearances necessary to supply energy for mining and smelting. Zn, Sb, Cd, and Cu distributions may result from diffusional and biological processes or from the influence of groundwater and underlying mineral soil, precluding their interpretation for historical reconstruction. The abundance of mineral resources, in addition to the strategic location, might explain why early settlers founded the city of Bibracte at that particular place. About 20% of the anthropogenic lead record was accumulated before our era and about 50% before the 18th century, which constitutes a troublesome heritage. Any attempts to develop control strategies in accumulating environments should take into account past human activities in order to not overestimate the impact of contemporary pollution.

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

    PubMed

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

    2015-08-01

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

  12. Atmospheric mercury deposition recorded in an ombrotrophic peat core from Xiaoxing'an Mountain, Northeast China

    SciTech Connect

    Tang, Shunlin; Huang, Zhongwei; Liu, Jun; Yang, Zaichan; Lin, Qinhua

    2012-10-15

    The historical mercury accumulation rates (Hg AR) resulting from atmospheric deposition to Xiaoxing'an Mountain were determined via analysis of {sup 210}Pb- and {sup 14}C-dated cores up to 5000 years old. Natural Hg AR background, pre-industrial Hg AR and maximum industrial Hg AR in Northeast China were 2.2 {+-}1.0 {mu}g/m{sup 2}/yr for 5100-4500 BP, 5.7 {mu}g/m{sup 2}/yr and 112.4 {mu}g/m{sup 2}/yr, respectively. We assumed that the increase in Hg deposition in the Xiaoxing'an mountain area during industrial time was mainly attributed to local anthropogenic emissions around this peat bog.

  13. Integrating the EMPD with an Alpine altitudinal training set to reconstruct climate variables in Holocene pollen records from high-altitude peat bogs

    NASA Astrophysics Data System (ADS)

    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

  14. Paleontological analysis of a lacustrine carbonaceous uranium deposit at the Anderson mine, Date Creek basin, west-central Arizona (U.S.A.)

    USGS Publications Warehouse

    Otton, J.K.; Bradbury, J.P.; Forester, R.M.; Hanley, J.H.

    1990-01-01

    The Tertiary sedimentary sequence of the Date Creek basin area of Arizona is composed principally of intertonguing alluvial-fan and lacustrine deposits. The lacustrine rocks contain large intermediate- to, locally, high-grade uranium deposits that form one of the largest uranium resources in the United States (an estimated 670,000 tons of U3O8 at an average grade of 0.023% is indicated by drilling to date). At the Anderson mine, about 50,000 tons of U3O8 occurs in lacustrine carbonaceous siltstones and mudstones (using a cutoff grade of 0.01%). The Anderson mine constitutes a new class of ore deposit, a lacustrine carbonaceous uranium deposit. Floral and faunal remains at the Anderson mine played a critical role in creating and documenting conditions necessary for uranium mineralization. Organic-rich, uraniferous rocks at the Anderson mine contain plant remains and ostracodes having remarkably detailed preservation of internal features because of infilling by opaline silica. This preservation suggests that the alkaline lake waters in the mine area contained high concentrations of dissolved silica and that silicification occurred rapidly, before compaction or cementation of the enclosing sediment. Uranium coprecipitated with the silica. Thinly laminated, dark-colored, siliceous beds contain centric diatoms preserved with carbonaceous material suggesting that lake waters at the mine were locally deep and anoxic. These alkaline, silica-charged waters and a stagnant, anoxic environment in parts of the lake were necessary conditions for the precipitation of large amounts of uranium in the lake-bottom sediments. Sediments at the Anderson mine contain plant remains and pollen that were derived from diverse vegetative zones suggesting about 1500 m of relief in the area at the time of deposition. The pollen suggests that the valley floor was semiarid and subtropical, whereas nearby mountains supported temperate deciduous forests. ?? 1990.

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

    NASA Astrophysics Data System (ADS)

    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

  16. Lake and Bog Sediment Records of Holocene Climate and Glacier Variability in the Cordillera Vilcabamba of Southern Peru

    NASA Astrophysics Data System (ADS)

    Schweinsberg, A.; Licciardi, J. M.; Rodbell, D. T.; Stansell, N.

    2013-12-01

    Records of past fluctuations in climatically sensitive tropical glaciers are among the best indicators of regional paleoclimatic trends and forcings. However, continuous sediment records in this region remain limited, particularly during the Holocene. Here we present the first continuous records of glacier activity in the Cordillera Vilcabamba (13°20'S) of southern Peru from lake and bog sediment cores in stratigraphic contact with 10Be-dated moraines. Completed analyses include sediment lithostratigraphy, magnetic susceptibility, and biogenic silica, in conjunction with AMS radiocarbon dates on charcoal. Carbon measurements, bulk density, and bulk sedimentation rates are used to derive a record of clastic sediment flux that serves as a proxy indicator of former glacier activity. Visually distinct sedimentological variations, magnetic susceptibility peaks, and radiocarbon dates were correlated among adjacent cores to construct one composite record representative of each coring site. Three composite cores are presented: two from the Rio Blanco valley and one from the Yanama valley. Sediment records from these two glaciated valleys suggest a series of environmental changes during the last ~12,000 calendar years BP. Clastic sediment flux trends are broadly consistent with published evidence that the early to middle Holocene was relatively warm and arid in the southern Peruvian Andes. An episode of high clastic flux in the late Holocene may reflect enhanced glacial activity in response to the onset of cooler and wetter conditions. A prominent peak in magnetic susceptibility at 1660 cal yr BP is present in all composite cores and serves as a chronostratigraphic marker. In addition, our new basal radiocarbon ages place limits on the cosmogenic 10Be production rate in the high Andes, suggesting the cosmogenic 10Be production rate is considerably lower than previously published estimates.

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

    PubMed

    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.

  18. Initiation of Sphagnum moss hummocks in bogs and the presence of vascular plants: Is there a link?

    NASA Astrophysics Data System (ADS)

    Pouliot, Rémy; Rochefort, Line; Karofeld, Edgar; Mercier, Caroline

    2011-07-01

    Establishment of specific vascular plants and Sphagnum species, as well as asymmetrical competition and facilitation between the two types of plants are apparently important in the development of microtopography in peatlands. To determine whether peatland vascular plants can facilitate the initiation of Sphagnum hummocks, and consequently the differentiation of bog microtopography, we investigated the effects of vascular plant life form and structure on Sphagnum stem length and biomass. We showed that Sphagnum stem length and biomass were enhanced by low density of vascular plants and other introduced structures, which thus favoured hummock formation. Dense covers of vascular plants also promoted moss height growth, but the Sphagnum stems were etiolated and fluffy, their densities were too low and biomass was too small to initiate clear hummocks. We also showed that vascular plants contributed to microhabitats with stable temperatures and high relative humidity favourable to Sphagnum growth. Stress-gradient hypothesis, predicting that the relative frequencies of facilitation and competition events will vary inversely along abiotic stress gradients, could explain the nature of the interaction between mosses and vascular plants. At the onset of microstructures formation in peatlands, abiotic stress is probably more important and facilitation events could be frequent. Microclimatic effects of vascular plants may be essential for Sphagnum growth. Then, the presence of ericaceous shrubs or young trees enhances the microtopography by physically reinforcing the hummocks. During accentuation of microtopography, the positive interactions between Sphagnum mosses and vascular plants may be replaced by competition as abiotic stress declines. This study introduces new evidence for the role of vascular plants in the formation and maintenance of hummocks, especially under drier growing conditions.

  19. Ditch blocking, water chemistry and organic carbon flux: evidence that blanket bog restoration reduces erosion and fluvial carbon loss.

    PubMed

    Wilson, Lorraine; Wilson, Jared; Holden, Joseph; Johnstone, Ian; Armstrong, Alona; Morris, Michael

    2011-05-01

    The potential for restoration of peatlands to deliver benefits beyond habitat restoration is poorly understood. There may be impacts on discharge water quality, peat erosion, flow rates and flood risk, and nutrient fluxes. This study aimed to assess the impact of drain blocking, as a form of peatland restoration, on an upland blanket bog, by measuring water chemistry and colour, and loss of both dissolved (DOC) and particulate organic carbon (POC). The restoration work was designed to permit the collection of a robust experimental dataset over a landscape scale, with data covering up to 3 years pre-restoration and up to 3 years post-restoration. An information theoretic approach to data analyses provided evidence of a recovery of water chemistry towards more 'natural' conditions, and showed strong declines in the production of water colour. Drain blocking led to increases in the E4:E6 ratio, and declines in specific absorbance, suggesting that DOC released from blocked drains consisted of lighter, less humic and less decomposed carbon. Whilst concentrations of DOC showed slight increases in drains and streams after blocking, instantaneous yields of both DOC and POC declined markedly in streams over the first year post-restoration. Attempts were made to estimate total annual fluvial organic carbon fluxes for the study site, and although errors around these estimates remain considerable, there is strong evidence of a large reduction in aquatic organic carbon flux from the peatland following drain-blocking. Potential mechanisms for the observed changes in water chemistry and organic carbon release are discussed, and we highlight the need for more detailed information, from more sites, to better understand the full impacts of peatland restoration on carbon storage and release.

  20. The effects of ecological restoration on CO2 fluxes from a climatically marginal upland blanket bog

    NASA Astrophysics Data System (ADS)

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

    2013-04-01

    A legacy of gully incision, deposition of industrially-derived aerial pollutants, inappropriate management and wildfire has left large expanses of the topographic Bleaklow Plateau (Peak District National Park, England, UK) bare of vegetation and susceptible to massive erosion of the peat soils. The consequence of such degradation has been to decrease the capacity of the peatland on the plateau to provide important ecosystem services including; loss of net C sink function, discolouration of surface waters, mobilisation to surface waters of stored heavy metals and infilling of upland reservoirs with peat-derived sediment. In response to on-going and worsening degradation a programme of ecological restoration has been undertaken. Restoration methods include: seeding with a lawn grass mix; liming; fertilisation; slope stabilisation; and gully blocking. This talk will present data from a five-year, observational-study of CO2 fluxes from eight sites, with four sites sampling different restoration treatments and four sampling bare and least disturbed areas. The results of the analysis reveal that sites with revegetation alongside slope stabilisation were most productive and were the largest net (daylight hours) sinks of CO2. Unrestored, bare sites, while having relatively low gross fluxes of CO2 were the largest net sources of CO2. Revegetation without slope stabilisation took longer (~18 months) to show an impact on CO2 flux in comparison to the sites with slope stabilisation. Binary logistic regression indicated that a ten centimetre increase in water table depth decreases the odds of observing a net CO2 sink, on a given site, by up to 30%. Sites with slope stabilisation were between 5-8x more likely to be net CO2 sinks than the bare sites. Sites without slope stabilisation were only 2-2.3x more likely to be net CO2 sinks compared to the bare sites. The most important conclusion of this research is that revegetation appears to be effective at increasing the likelihood

  1. 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

    NASA Astrophysics Data System (ADS)

    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.

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

    USGS Publications Warehouse

    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.

  3. Zonal Features of Bog and Lake Water Chemistry Along a Transect from Boreal to Arid Landscapes in The South of Western Siberia, Russia

    NASA Astrophysics Data System (ADS)

    Kolpakova, Marina N.; Naymushina, Olga S.

    2016-10-01

    Western Siberia is a unique territory where more than 12000 water reservoirs are located. The region is characterized by high bogginess up to 90% in the north. Bog and lake systems are able to accumulate natural and technogenic resources, including trace elements and organic matter. The article presents the results of a surface water chemical composition along a 5-year monitoring. The obtained data allow concluding that dynamics of water chemistry is predetermined by their location in various landscape zones and subordinated to zonal distribution of such major landscape elements as moistening, evaporation, rate of groundwater flow, etc.

  4. National Program for Inspection of Non-Federal Dams. Bog Brook Dam (NH 00194) (NHWRB 220.16) Connecticut River Basin, Springfield, New Hampshire. Phase I Inspection Report.

    DTIC Science & Technology

    1980-07-01

    AD-RI56 391 NATIONAL PROGRAM FOR INSPECTION OF NON-FEDERAL DAMS BOG 1/1 BROOK DAM (NH 9iI (U) CORPS OF ENGINEERS WALTHAN MR NEW ENGLAND DIV JUL 8B...UNCLASSIFIED F/G 13/03 NL mmmhhmmhhhlI ommhhmhmhhm.EomhhmhoE-EEE hmhhhhhhmmonsl I I fl 1 I.15 111_ _ 1.6 CONNECTICUT RIVER BASIN SPRINGFIELD, NEW...CORPS OF ENGINEERS WALTHAM, MASS. 02154 JULY 1980 , D11tC EiLf. WE Y NATIONAL DAM INSPECTION PROGRAM PPHASE I INSPECTION REPORT Identification No.: NH

  5. Uranium and organic matters: use of pyrolysis-gas chromatography, carbon, hydrogen, and uranium contents to characterize the organic matter from sandstone-type deposits

    USGS Publications Warehouse

    Leventhal, Joel S.

    1979-01-01

    Organic matter seems to play an important role in the genesis of uranium deposits in sandstones in the western United States. Organic materials associated with ore from the Texas coastal plain, Tertiary basins of Wyoming, Grants mineral belt of New Mexico, and the Uravan mineral belt of Utah and Colorado vary widely in physical appearance and chemical composition. Partial characterization of organic materials is achieved by chemical analyses to determine atomic hydrogen-to-carbon (H/C) ratios and by gas chromatographic analyses to determine the molecular fragments evolved during stepwise pyrolysis. From the pyrolysis experiments the organic materials can be classified and grouped: (a) lignites from Texas and Wyoming and (b) hydrogen poor materials, from Grants and Uravan mineral belts and Wyoming; (c) naphthalene-containing materials from Grants mineral belt and Wyoming; and (d) complex and aromatic materials from Uravan, Grants and Wyoming. The organic materials analyzed have atomic H/C ratios that range from approximately 0.3 to at least 1.5. The samples with higher H/C ratios yield pyrolysis products that contain as many as 30 carbon atoms per molecule. Samples with low H/C ratios are commonly more uraniferous and yield mostly methane and low-molecular-weight gases during pyrolysis.

  6. Geochronology and Fluid-Rock Interaction Associated with the Nopal I Uranium Deposit, Pena Blanca, Mexico

    SciTech Connect

    M. Fayek; P. Goodell; M. Ren; A. Simmons

    2005-07-11

    The Nopal I uranium (U) deposit, Pena Blanca District, Mexico, largely consists of secondary U{sup 6+} minerals, which occur within a breccia pipe mainly hosted by the 44 Ma Nopal and Colorados volcanic formations. These two units overly the Pozos conglomerate formation and Cretaceous limestone. Three new vertical diamond drill holes (DDHs) were recently drilled at Nopal I. DDH-PB1 with continuous core was drilled through the Nopal I deposit and two additional DDHs were drilled {approx}50 m on either side of the cored hole. These DDHs terminate 20 m below the current water table, thus allowing the detection of possible gradients in radionuclide contents resulting from transport from the overlying uranium deposit. Primary uraninite within the main ore body is rare and fine-grained ({approx}50 micrometers), thus making geochronology of the Nopal I deposit very difficult. Uranium, lead and oxygen isotopes can be used to study fluid-uraninite interaction, provided that the analyses are obtained on the micro-scale. Secondary ionization mass spectrometry (SIMS) permits in situ measurement of isotopic ratios with a spatial resolution on the scale of a few {micro}m. Preliminary U-Pb results show that uraninite from the main ore body gives an age of 32 {+-} 8 Ma, whereas uraninite from the uraniferous Pozos conglomerate that lies nearly 100 m below the main ore body and 25 meters above the water table, gives a U-Pb age that is <1 Ma. Oxygen isotopic analyses show that uraninite from the ore body has a {delta}{sup 18}O = -10.8{per_thousand}, whereas the uraninite within the Pozos conglomerate has a {delta}{sup 18}O = +1.5{per_thousand}. If it is assumed that both uraninites precipitated from meteoric water ({delta}{sup 18}O = -7{per_thousand}), then calculated precipitation temperatures are 55 C for the uraninite from the ore body and 20 C for uraninite hosted by the Pozos conglomerate. These temperatures are consistent with previous studies that calculated precipitation

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

    USGS Publications Warehouse

    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.

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

    PubMed

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

    2015-12-01

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

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

    PubMed

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

    2013-01-01

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

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

    NASA Astrophysics Data System (ADS)

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

    2012-12-01

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

  11. Holocene climate dynamics in the Eastern Italian Alps: a multi-proxy study from ice and peat bogs

    NASA Astrophysics Data System (ADS)

    Poto, Luisa; Gabrieli, Jacopo; Segnana, Michela; Festi, Daniela; Oeggl, Klaus; Barbante, Carlo

    2014-05-01

    The Eastern Italian Alps are located near one of the areas in the world with some of the longest records of extreme environmental use by human activity. In this area, paleo-climate studies are hampered by the lack of high-resolution multi-proxy records with adequate chronological control. With this project, we propose to reconstruct Holocene climatic and environmental variations in the Eastern Italian Alps using terrestrial and glaciological archives. We aim to study the characteristics of different climate stages in this sector of the Alps using an ice core drilled on the top of the Ortles glacier (46°30' N, 10°32 E, 3850 m a.s.l.) and ombrotrophic peat bog records from the Dolomites (Danta di Cadore, 46°34' N, 12°33 E, 1400 m a.s.l. and Coltrondo 46°39'28.37''N 12°26'59.17''E, 1800 m a.s.l., Belluno province). The study of global climatic change require a holistic and multi-proxy approach to better understand several complex and often non-linear relationships. In the Italian Alps our study on peat cores represents the first attempt where a multi-proxy approach is applied, and here we report our first results. A 7.0 m peat sequence was extracted in Danta di Cadore. The depth-age scale, based upon independent 14C and 210Pb dates and modeled with the Clam method (Blaauw, 2010), demonstrates that the archive covers more than 13,200 years (cal BP). We determined physical proprieties, Ca and Ti trends, pore water pH, conductivity, and Ca/Mg ratios to identify changes in trophic conditions. The results confirm that the uppermost 400 cm are composed of ombrotrophic peat representing the longest Eastern Alpine ombrotrophic record yet obtained, covering the last 7,000 years. The oldest radiocarbon age (13,200 years cal BP) provides evidence that, during the Bölling-Alleröd interstadial, the upper part of the Piave Glacier was ice-free up to 1400 m a.s.l.. At that time pollen assemblages show that a conifer forest characterized the local vegetation. This forest was

  12. Deposition head for laser

    DOEpatents

    Lewis, Gary K.; Less, Richard M.

    1999-01-01

    A deposition head for use as a part of apparatus for forming articles from materials in particulate form in which the materials are melted by a laser beam and deposited at points along a tool path to form an article of the desired shape and dimensions. The deposition head delivers the laser beam and powder to a deposition zone, which is formed at the tip of the deposition head. A controller comprised of a digital computer directs movement of the deposition zone along the tool path and provides control signals to adjust apparatus functions, such as the speed at which the deposition head moves along the tool path.

  13. Effects of experimental nitrogen deposition on peatland carbon pools and fluxes: a modelling analysis

    NASA Astrophysics Data System (ADS)

    Wu, Y.; Blodau, C.; Moore, T. R.; Bubier, J.; Juutinen, S.; Larmola, T.

    2015-01-01

    Nitrogen (N) pollution of peatlands alters their carbon (C) balances, yet long-term effects and controls are poorly understood. We applied the model PEATBOG to explore impacts of long-term nitrogen (N) fertilization on C cycling in an ombrotrophic bog. Simulations of summer gross ecosystem production (GEP), ecosystem respiration (ER) and net ecosystem exchange (NEE) were evaluated against 8 years of observations and extrapolated for 80 years to identify potential effects of N fertilization and factors influencing model behaviour. The model successfully simulated moss decline and raised GEP, ER and NEE on fertilized plots. GEP was systematically overestimated in the model compared to the field data due to factors that can be related to differences in vegetation distribution (e.g. shrubs vs. graminoid vegetation) and to high tolerance of vascular plants to N deposition in the model. Model performance regarding the 8-year response of GEP and NEE to N input was improved by introducing an N content threshold shifting the response of photosynthetic capacity (GEPmax) to N content in shrubs and graminoids from positive to negative at high N contents. Such changes also eliminated the competitive advantages of vascular species and led to resilience of mosses in the long-term. Regardless of the large changes of C fluxes over the short-term, the simulated GEP, ER and NEE after 80 years depended on whether a graminoid- or shrub-dominated system evolved. When the peatland remained shrub-Sphagnum-dominated, it shifted to a C source after only 10 years of fertilization at 6.4 g N m-2 yr-1, whereas this was not the case when it became graminoid-dominated. The modelling results thus highlight the importance of ecosystem adaptation and reaction of plant functional types to N deposition, when predicting the future C balance of N-polluted cool temperate bogs.

  14. Effects of experimental nitrogen deposition on peatland carbon pools and fluxes: a modeling analysis

    NASA Astrophysics Data System (ADS)

    Wu, Y.; Blodau, C.; Moore, T. R.; Bubier, J. L.; Juutinen, S.; Larmola, T.

    2014-07-01

    Nitrogen (N) pollution of peatlands alters their carbon (C) balances, yet long-term effects and controls are poorly understood. We applied the model PEATBOG to analyze impacts of long-term nitrogen (N) fertilization on C cycling in an ombrotrophic bog. Simulations of summer gross ecosystem production (GEP), ecosystem respiration (ER) and net ecosystem exchange (NEE) were evaluated against 8 years of observations and extrapolated for 80 years to identify potential effects of N fertilization and factors influencing model behavior. The model successfully simulated moss decline and raised GEP, ER and NEE on fertilized plots. GEP was systematically overestimated in the model compared to the field data due to high tolerance of Sphagnum to N deposition in the model. Model performance regarding the 8 year response of GEP and NEE to N was improved by introducing an N content threshold shifting the response of photosynthesis capacity to N content in shrubs and graminoids from positive to negative at high N contents. Such changes also eliminated the competitive advantages of vascular species and led to resilience of mosses in the long-term. Regardless of the large changes of C fluxes over the short-term, the simulated GEP, ER and NEE after 80 years depended on whether a graminoid- or shrub-dominated system evolved. When the peatland remained shrub-Sphagnum dominated, it shifted to a C source after only 10 years of fertilization at 6.4 g N m-2 yr-1, whereas this was not the case when it became graminoid-dominated. The modeling results thus highlight the importance of ecosystem adaptation and reaction of plant functional types to N deposition, when predicting the future C balance of N-polluted cool temperate bogs.

  15. Novel interconnect deposition technology

    NASA Astrophysics Data System (ADS)

    Speckman, D. M.; Wendt, J. P.

    1991-12-01

    A new series of experiments was initiated to improve current interconnect deposition technology for integrated circuits. Preliminary aluminum deposition experiments were carried out using trimethylamine(alane) as the precursor, and some mildly reflective, uniform aluminum films were successfully deposited on glass slides, suggesting that chemical vapor deposition (CVD) will be a practicable deposition technique for advanced integrated circuit interconnect films. CVD studies of aluminum and zirconium- and hafnium-diboride thin films are continuing.

  16. Deposit model for volcanogenic uranium deposits

    USGS Publications Warehouse

    Breit, George N.; Hall, Susan M.

    2011-01-01

    The International Atomic Energy Agency's tabulation of volcanogenic uranium deposits lists 100 deposits in 20 countries, with major deposits in Russia, Mongolia, and China. Collectively these deposits are estimated to contain uranium resources of approximately 500,000 tons of uranium, which amounts to 6 percent of the known global resources. Prior to the 1990s, these deposits were considered to be small (less than 10,000 tons of uranium) with relatively low to moderate grades (0.05 to 0.2 weight percent of uranium). Recent availability of information on volcanogenic uranium deposits in Asia highlighted the large resource potential of this deposit type. For example, the Streltsovskoye district in eastern Russia produced more than 100,000 tons of uranium as of 2005; with equivalent resources remaining. Known volcanogenic uranium deposits within the United States are located in Idaho, Nevada, Oregon, and Utah. These deposits produced an estimated total of 800 tons of uranium during mining from the 1950s through the 1970s and have known resources of 30,000 tons of uranium. The most recent estimate of speculative resources proposed an endowment of 200,000 tons of uranium.

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

    NASA Astrophysics Data System (ADS)

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

    2017-01-01

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

  18. Differences in hydrophyte life forms induce spatial heterogeneity of CH4 production and its carbon isotopic signature in a temperate bog peatland

    NASA Astrophysics Data System (ADS)

    Itoh, Masayuki; Shimamura, Tetsuya; Ohte, Nobuhito; Takemon, Yasuhiro

    2015-07-01

    To clarify the effect of differences in hydrophyte life forms on methane (CH4) production and its carbon stable isotopic signature (δ13C-CH4), we analyzed CH4 and carbon dioxide (CO2) concentrations, their stable carbon isotope values, and chemical constituents dissolved in pore water in a small floating peat bog in Japan. Because eutrophication has modified the surrounding water quality, the bog vegetation on the mat has been, in part, replaced by fen-type vegetation. We hypothesized that differences in hydrophyte habitats affect redox conditions, including dissolved oxygen (DO) in water and therefore the amounts and carbon isotopic values of CH4 and CO2 dissolved in pore water. Between the habitats of two Sphagnum species, DO was considerably higher, and CH4 concentrations were significantly lower in Sphagnum cuspidatum Ehrh. habitats in hollow (DO: 0.62 ± 0.20 mg/L (standard error (SE)) and CH4: 0.18 ± 0.02 mmol/L) than in Sphagnum palustre L. habitats in hummock (DO: 0.29 ± 0.08 and CH4: 0.82 ± 0.06) in pore water (10 cm depth). Both DO and CH4 concentrations in three vascular plant habitats (Rhynchospora fauriei Franch., Phragmites australis [reed], and Menyanthes trifoliata L.) in pore water (10 cm depth) were intermediate relative to the two Sphagnum species. However, CH4 flux in M. trifoliata site was significantly higher than that at both Sphagnum sites, suggesting that the type of gas transport (diffusive or convective via root and stem) affected the depth profile of CH4 concentrations and its flux. δ13C-CH4 values in pore water also varied among the vegetation types, even within Sphagnum species (e.g., at 10 cm depth, δ13C-CH4: R. fauriei, -55.3 ± 1.8‰ (SE); P. australis, -57.5 ± 1.6‰; M. trifoliata, -56.7 ± 1.5‰; S. cuspidatum, -71.2 ± 1.4‰; and S. palustre, -60.4 ± 0.6‰). Our results suggest that significant differences arise in CH4 concentration and δ13C-CH4 values among the hydrophyte habitats even within a small peat bog and

  19. Small-scale spatial heterogeneity as a source for uncertainty of methane fluxes in an extensive near-natural bog-ecosystem

    NASA Astrophysics Data System (ADS)

    Hommeltenberg, J.; Schmid, H. P. E.; Bechtold, M.; Tiemeyer, B.

    2015-12-01

    Natural and restored peatlands are often a strong source of the greenhouse gas methane (CH4). CH4 fluxes vary greatly between different peatland ecosystems, depending on temperature, water level and vegetation. In addition, peatlands often show high small-scale spatial heterogeneity that strongly influences the magnitude of CH4 production. This heterogeneity potentially induce a sensor location bias and leads to additional uncertainties due to the flux footprint variability over heterogeneous terrain. To account for such uncertainty, we installed two eddy covariance towers 26 m apart (height: 6 m) to measure the CH4 flux, together with latent heat and CO2 fluxes at the bog ecosystem "Schechenfilz" in southern Germany. The study site is a large near-natural bog (111 ha) with heterogeneity that is characterized by patches of bog-pine forest, sedge meadows, peat mosses and open water areas. Ongoing CH4 measurements on one of the towers began in July 2012, and both towers were operated with a LI-7700 to measure the CH4 flux simultaneously from autumn 2014 to early spring 2015. In a second campaign, from mid-October to mid-November 2014, both instruments were operated at the same tower for comparison. Throughout the investigation, 17 water level gauges were used to measure the temporal variability of the water level in the mean footprint area. The water level was interpolated based on a high-resolution digital terrain model, which also allows us to account for the impact of the spatial variability of the water table. A vegetation map focused on the distribution of plants with aerenchymous tissues was used to determine the influence of the vegetation composition on the CH4 exchange. In this study, we estimated the uncertainty of CH4 fluxes induced by the instrument system and the flux footprint variability. The footprint analyses together with the water table measurements and vegetation map were also used to analyze the impact of small-scale spatial heterogeneity on the

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

    NASA Astrophysics Data System (ADS)

    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

  1. Export of dissolved organic carbon and nitrogen from drained and re-wetted bog sites in Lower Saxony (Germany)

    NASA Astrophysics Data System (ADS)

    Frank, Stefan; Tiemeyer, Bärbel; Freibauer, Annette

    2014-05-01

    Today, nearly all peatlands in Germany are drained for agriculture, forestry and peat cutting. The export of dissolved organic carbon (C) and nitrogen (N) may be important for the overall C and N balances and affects downstream ecosystems. While drainage generally increases solute losses, there is nearly no C and N export data of raised bogs in Germany which can be used to evaluate both the impact of drainage associated with intensive land use and the re-wetting of peat cutting sites. In the "Ahlenmoor" (North-Western Germany), four sampling points were chosen. Three sampling points represent a deeply drained intensively used grassland at various scales ranging from a drainage pipe (DP, 0.08 ha) and a drainage ditch (DD, 6.8 ha) to a collector ditch (CD, 20 ha). The fourth sampling point (RW) is a former peat cutting site (23 ha) re-wetted 10 years ago. At this site, polder technique was used to establish water tables at the soil surface. Sampling and discharge measurements were conducted bi-weekly from June 2011 to June 2013. Water table levels were recorded with automatic pressure sensors, and rating curves between discharge and water levels were used to calculate continuous discharge values. Samples were analyzed for dissolved organic carbon (DOC), particulate organic carbon (POC), dissolved organic nitrogen (DON), ammonium (NH4+), nitrate (NO3-), sulphate (SO42-), pH, electric conductivity (EC) and specific UV absorbance (SUVA). The discharge did not vary strongly between the sampling points and was slightly lower in the second year. Concentrations of all measured solutes were higher at the intensive grassland (DP, DD and CD) than at the re-wetted site. Surprisingly, SUVA showed no difference between all sites, while the DOC to DON ratio was narrower at DP, DD and CD than at RW. This indicates an export of more degraded dissolved organic matter (DOM) from the drained area. At the grassland sites, no statistical differences were found between the three scales

  2. An attempt to compare variations of carbon stable isotopes composition in two replicate cores from a Baltic bog in N Poland

    NASA Astrophysics Data System (ADS)

    Pawlyta, Jacek; Lamentowicz, Mariusz; Goslar, Tomasz

    2010-05-01

    Two one-meter long monolith cores were taken from Stążki mire. Stążki mire is well preserved Baltic type raised bog with a very small evidence of exploitation. Stable isotopic composition of carbon (13C) was investigated in the bulk organic matter of Sphagnum. One centimetre resolution sampling was chosen for the investigation. Only carefully selected, leaf-free Sphagnum stems were collected for the study. Isotopic composition was determined using elemental analyser coupled to isotopic ratio mass spectrometer. For the correlation purposes age-depth models were established for both monoliths. Radiocarbon dating and 210Pb dating results were used to obtain the age-depth model for one monolith. Age-depth model for the second monolith was based on radiocarbon dating only. Both cores covered the last 1200 years of Stążki mire history. We will present a detailed comparison of correlate isotopic signal from Sphagnum in both cores.

  3. Rouxiella badensis sp. nov. and Rouxiella silvae sp. nov. isolated from peat bog soil in Germany and emendation of the genus description.

    PubMed

    LE Fleche-Mateos, Anne; Kugler, Johannes H; Hansen, Silla H; Syldatk, Christoph; Hausmann, Rudolf; Lomprez, Fabienne; Vandenbogaert, Mathias; Manuguerra, Jean-Claude; Grimont, Patrick A D

    2017-01-16

    Four bacterial strains isolated from peat bog soil or swampy meadow in Baden-Württemberg (Germany) and found to have rrs sequences close to that of Rouxiella chamberiensis were compared to this species by multi-locus sequence analysis and phenotypic tests. The four strains constituted two discrete groups (referred to as Baden and Silva groups) belonging to the genus Rouxiella. These groups differed in the ability to grow at 37°C, reduce nitrate into nitrite, and produce acid from several carbohydrates. Two new species are therefore proposed, Rouxiella badensis sp. nov. for the Baden group (type strain, 323T = CIP 111153T = DSM 100043T) and Rouxiella silvae for the Silva group (type strain, 213T = CIP 111154T = DSM 103735T ). The definition of the genus Rouxiella is emended to take the new species into account.

  4. Tundra in the rain: differential vegetation responses to three years of experimentally doubled summer precipitation in Siberian shrub and Swedish bog tundra.

    PubMed

    Keuper, Frida; Parmentier, Frans-Jan W; Blok, Daan; van Bodegom, Peter M; Dorrepaal, Ellen; van Hal, Jurgen R; van Logtestijn, Richard S P; Aerts, Rien

    2012-01-01

    Precipitation amounts and patterns at high latitude sites have been predicted to change as a result of global climatic changes. We addressed vegetation responses to three years of experimentally increased summer precipitation in two previously unaddressed tundra types: Betula nana-dominated shrub 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 increments) and Arctagrostis latifolia (leaf size and specific leaf area), but none were observed at the Swedish site. Total biomass production did not increase at either of the study sites. This study corroborates studies in other tundra vegetation types and shows that despite regional differences at the plant level, total tundra plant productivity is, at least at the short or medium term, largely irresponsive to experimentally increased summer precipitation.

  5. Using Optical Oxygen Sensors and Injection Experiments to Determine in situ Microbial Rate Constants for Methane Oxidation and Heterotrophic Respiration in a Boreal Bog and Fen

    NASA Astrophysics Data System (ADS)

    Waldo, N.; Moorberg, C.; Waldrop, M. P.; Turetsky, M. R.; Neumann, R. B.

    2015-12-01

    Wetlands are the largest natural source of methane to the atmosphere, and play a key role in feedback cycles to climate change. In recognition of this, many researchers are developing process-based models of wetland methane emissions at various scales. In these models, the three key biogeochemical reactions are methane production, methane oxidation, and heterotrophic respiration, and they are modeled using Michaelis-Menten kinetics. The majority of Michaelis-Menten rate constants used in models are based on experiments involving slurries of peat incubated in vials. While these slurries provide a highly controlled setting, they are different from in situ conditions in multiple ways; notably they lack live plants and the centimeter-scale heterogeneities that exist in the field. To determine rate constants in a system more representative of in situ conditions, we extracted peat cores intact from a bog and fen located in the Bonanza Creek Experimental Forest near Fairbanks, Alaska and part of the Alaska Peatland Experiment (APEX) research program. Into those cores we injected water with varying concentrations of methane and oxygen at multiple depths. We used planar oxygen sensors installed on the peat cores to collect high resolution, two dimensional oxygen concentration data during the injections and used oxygen consumption rates under various conditions to calculate rate constants. Results were compared to a similar but smaller set of injection experiments conducted against planar oxygen sensors installed in the bog. Results will inform parametrization of microbial processes in wetland models, improving estimates of methane emissions both under current climate conditions and in the future.

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

    PubMed

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

    2012-11-01

    Litter decomposition and nutrient mineralization in high-latitude peatlands are constrained by low temperatures. So far, little is known about the effects of seasonal components of climate change (higher spring and summer temperatures, more snow which leads to higher winter soil temperatures) on these processes. In a 4-year field experiment, we manipulated these seasonal components in a sub-arctic bog and studied the effects on the decomposition and N and P dynamics of leaf litter of Calamagrostis lapponica, Betula nana, and Rubus chamaemorus, incubated both in a common ambient environment and in the treatment plots. Mass loss in the controls increased in the order Calamagrostis < Betula < Rubus. After 4 years, overall mass loss in the climate-treatment plots was 10 % higher compared to the ambient incubation environment. Litter chemistry showed within each incubation environment only a few and species-specific responses. Compared to the interspecific differences, they resulted in only moderate climate treatment effects on mass loss and these differed among seasons and species. Neither N nor P mineralization in the litter were affected by the incubation environment. Remarkably, for all species, no net N mineralization had occurred in any of the treatments during 4 years. Species differed in P-release patterns, and summer warming strongly stimulated P release for all species. Thus, moderate changes in summer temperatures and/or winter snow addition have limited effects on litter decomposition rates and N dynamics, but summer warming does stimulate litter P release. As a result, N-limitation of plant growth in this sub-arctic bog may be sustained or even further promoted.

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

    PubMed

    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.

  8. Origin and depositional environment of clastic deposits in the Hilo drill hole, Hawaii

    USGS Publications Warehouse

    Beeson, M.H.; Clague, D.A.; Lockwood, J.P.

    1996-01-01

    Volcaniclastic units cored at depths of about 87, 164, 178, 226, and 246 m below sea level and carbonate units located between depths of 27 and 53 m below sea level in the Hilo drill core were found to be deposited at or near sea level. Four of these units are hydroclastic deposits, formed when subaerially erupted Mauna Loa lava flows entered the ocean and fragmented to produce quenched, glassy fragments during hydrovolcanic explosions. Ash units 24 and 26, at 178 m depth, accumulated at sea level in a freshwater bog. They contain pyroxenes crystallized from tholeiitic magma that we infer erupted explosively at the summit of Kilauea volcano. Two carbon-rich layers from these ashes have a weighted average radiocarbon age of 38.6 ?? 0.9 ka; the ashes probably correlate with the oldest and thickest part of the Pahala ash. Ash unit 44, at the transition from Mauna Kea to Mauna Loa lava flows, was probably nearly 3.2 m thick and is inferred to be equivalent to the lower thick part of the composite Homelani ash mapped in Hilo and on the flanks of Mauna Kea. The age of this part of Homelani ash is between 128 ?? 33 and 200 ?? 10 ka; it may have erupted subglacially during the Pohakuloa glacial maxima on Mauna Kea. Beach sand units 12 and 22 were derived from nearby Mauna Loa and Mauna Kea lava flows. The middle of beach sand unit 38 was derived mainly from lava erupted near the distal end of the subaerial east rift zone of Kilauea volcano; these sands were transported about 33 km northwest to Hilo Bay by prevailing longshore currents. Combined age, depth, and sea level markers in the core allow us to determine that lava flow recurrence intervals averaged one flow every 4 kyr during the past 86 kyr and one flow every 16 kyr between 86 and 200 ka at the drill site and that major explosive eruptions that deposit thick ash in Hilo have occurred only twice in the last 400 kyr. These recurrence intervals support the moderate lava flow hazard zonation (zone 3) for coastal Hilo

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

    EPA Science Inventory

    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...

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

    EPA Science Inventory

    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 ...

  11. Peat Bog Wildfire Smoke Exposure in Rural North Carolina Is Associated with Cardiopulmonary Emergency Department Visits Assessed Through Syndromic Surveillance

    EPA Science Inventory

    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 is...

  12. 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).

    NASA Astrophysics Data System (ADS)

    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

  13. Biomimetic thin film deposition

    NASA Astrophysics Data System (ADS)

    Rieke, P. C.; Campbell, A. A.; Tarasevich, B. J.; Fryxell, G. E.; Bentjen, S. B.

    1991-04-01

    Surfaces derivatized with organic functional groups were used to promote the deposition of thin films of inorganic minerals. These derivatized surfaces were designed to mimic the nucleation proteins that control mineral deposition during formation of bone, shell, and other hard tissues in living organisms. By the use of derivatized substrates control was obtained over the phase of mineral deposited, the orientation of the crystal lattice and the location of deposition. These features are of considerable importance in many technically important thin films, coatings, and composite materials. Methods of derivatizing surfaces are considered and examples of controlled mineral deposition are presented.

  14. Dry deposition velocities

    SciTech Connect

    Sehmel, G.A.

    1984-03-01

    Dry deposition velocities are very difficult to predict accurately. In this article, reported values of dry deposition velocities are summarized. This summary includes values from the literature on field measurements of gas and particle dry deposition velocities, and the uncertainties inherent in extrapolating field results to predict dry deposition velocities are discussed. A new method is described for predicting dry deposition velocity using a least-squares correlation of surface mass transfer resistances evaluated in wind tunnel experiments. 14 references, 4 figures, 1 table.

  15. Handbook on surficial uranium deposits. Chapter 3. World distribution relative to climate and physical setting

    SciTech Connect

    Carlisle, D

    1983-01-01

    This chapter discusses regional controls which affect the world distribution of surficial chemogenic uranium deposits. The most important of these are (1) climate, (2) geomorphology, including physiographic and climatic stability, and (3) provenance, i.e., the weathering terrain from which uranium and associated substances are derived. The three economically important environments are the calcrete environment, simple evaporative environments and paludal environments. Of these three categories, the calcrete uranium environment is probably the most uniquely constrained in terms of regional climate, geomorphic setting, provenance (vanadium as well as uranium) and especially the need for long term stability of both climate and physiography. Purely evaporative deposits, though subject to some of the same kinds of constraints, can also reflect local circumstances and a wider range of climates, physiographic settings, and source terrains. The third category encompassing bogs, marshes and organic-rich playas can form under an even wider range of climates and settings provided only that organic materials accumulate in abundance and are contacted by uranium-bearing waters. For all of these reasons and also because of the great economic importance of the calcrete environment as well as its relative novelty and complexity the discussion in this chapter is focused on calcrete, dolocrete and gypcrete uranium deposits. Objective data are reviewed first follwed by inferences and suggestions. 13 figures.

  16. 78 FR 56583 - Deposit Insurance Regulations; Definition of Insured Deposit

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-13

    ... Part 330 RIN 3064-AE00 Deposit Insurance Regulations; Definition of Insured Deposit AGENCY: Federal...)(1), 12 U.S.C. 1821(f)(1). A. Definition of ``Deposit'' The term ``deposit'' is defined in section 3... between domestic and foreign deposits. The current statutory definition of ``deposit'' under section...

  17. Airfoil deposition model

    NASA Technical Reports Server (NTRS)

    Kohl, F. J.

    1982-01-01

    The methodology to predict deposit evolution (deposition rate and subsequent flow of liquid deposits) as a function of fuel and air impurity content and relevant aerodynamic parameters for turbine airfoils is developed in this research. The spectrum of deposition conditions encountered in gas turbine operations includes the mechanisms of vapor deposition, small particle deposition with thermophoresis, and larger particle deposition with inertial effects. The focus is on using a simplified version of the comprehensive multicomponent vapor diffusion formalism to make deposition predictions for: (1) simple geometry collectors; and (2) gas turbine blade shapes, including both developing laminar and turbulent boundary layers. For the gas turbine blade the insights developed in previous programs are being combined with heat and mass transfer coefficient calculations using the STAN 5 boundary layer code to predict vapor deposition rates and corresponding liquid layer thicknesses on turbine blades. A computer program is being written which utilizes the local values of the calculated deposition rate and skin friction to calculate the increment in liquid condensate layer growth along a collector surface.

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

    NASA Astrophysics Data System (ADS)

    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

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

    NASA Astrophysics Data System (ADS)

    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

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

    PubMed

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

    2016-01-01

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

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

    PubMed

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

    2012-05-01

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

  2. Ionized cluster beam deposition

    NASA Technical Reports Server (NTRS)

    Kirkpatrick, A. R.

    1983-01-01

    Ionized Cluster Beam (ICB) deposition, a new technique originated by Takagi of Kyoto University in Japan, offers a number of unique capabilities for thin film metallization as well as for deposition of active semiconductor materials. ICB allows average energy per deposited atom to be controlled and involves impact kinetics which result in high diffusion energies of atoms on the growth surface. To a greater degree than in other techniques, ICB involves quantitative process parameters which can be utilized to strongly control the characteristics of films being deposited. In the ICB deposition process, material to be deposited is vaporized into a vacuum chamber from a confinement crucible at high temperature. Crucible nozzle configuration and operating temperature are such that emerging vapor undergoes supercondensation following adiabatic expansion through the nozzle.

  3. Lipid D/H Ratios from Multiple Sources and Deposits Indicate Drier Little Ice Age at Washington Island (4°43`N, 160°25`W), Central Pacific

    NASA Astrophysics Data System (ADS)

    Muegler, I.; Sachse, D.; Sachs, J. P.

    2010-12-01

    To compare the sensitivity of biomarker D/H ratios from two distinct climate archives, a lake and a peat bog on the Tropical Pacific Island of Terrania, compound-specific hydrogen isotope ratios (expressed as δD values) were determined on lipid biomarkers from various biological sources deposited in the two climate archives. At present, Terrania or Washington Island (4°43`N, 160°25`W) permanently lies in the intertropical convergence zone (ITCZ) and receives an annual precipitation of 2,903 mm. The interior of this lens shaped island contains a freshwater lake and peat bogs. Previous studies on the lake sediments found evidence for a substantially drier climate at times during the Little Ice Age (AD 1400-1850) based on the lithologic transition from modern freshwater sediments to a sequence of pure cyanobacterial mat in concert with δD values from total lipid extracts (Sachs et al., 2009). Here we report on δD values from lipids of various sources: dinoflagellate algae (dinosterol and a saturated C30 sterol (4α -methyl-24-ethyl-5α -cholestan-3β-ol), microbial sources (diploptene and nC21 alkane) and higher plants (fern-7-ene, β-sitosterol and stigmastanol). Mean δD values from all lipids, measured in both archives, are significantly enriched in deuterium by between 22 and 86‰ during previously inferred drier climate conditions and simultaneously record the transition towards a freshwater lake at around AD1550. Measured δD values of all lipids cover a wide range from -281‰ to -105‰ during freshwater deposition and from -185‰ to -50‰ when climate was drier. In agreement with the observed isotopic difference between lipids produced via the acetogenic and the mevalonic acid biosynthetic pathway δD values for algae and higher plant sterols are depleted in deuterium relative to the nC21 alkane by 150‰ on average. The consistent δD values from dinosterol and 4α -methyl-24-ethyl-5α -cholestan-3β-ol from the lake and peat deposits signify the

  4. ElectroSpark Deposition

    DTIC Science & Technology

    2007-01-25

    ElectroSpark Deposition Hard Chrome Alternatives Team Joint Cadmium Alternatives Team Canadian Hard Chrome Alternatives Team Joint Group on Pollution...00-2007 to 00-00-2007 4. TITLE AND SUBTITLE ElectroSpark Deposition 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S...Processes, Inc. ElectroSpark Deposition (ESD) Results of Materials Testing and Technology Insertion January 25, 2007 Advanced Surfaces And Processes, Inc. 3

  5. Snow Accumulation and Spring Melt Rates of Bogs and Fens in the North Granny Creek Catchment Basin, Hudson Bay Lowlands, Ontario

    NASA Astrophysics Data System (ADS)

    Cook, C. F.; Price, J. S.

    2009-05-01

    The Hudson Bay Lowlands contain one of the most extensive, contiguous peatland complexes in the world. Interlinked patterned peatlands developed in this region because of the cool climate, low-gradient topography and an underlying layer of low conductivity marine sediments. There is currently little research regarding the mechanisms that control runoff and surface water connectivity in this region, especially the functions of different peatland types on runoff production and flow pathways. Runoff generation in these systems is dependent on several factors such as soil and pool storage capacity, snow accumulation and melt rates, and peatland morphometry. Snowmelt accounts for a major portion of total annual runoff in this region and the timing of the melt will determine effective runoff production from a peatland catchment. One of the objectives of this project is to identify the processes and mechanisms that generate spring snowmelt runoff in different peatland types (i.e. bogs and fens) and quantify the relative contribution of each type in a peatland-dominated catchment basin. This research is being conducted in a 30 km2 catchment basin located near the DeBeers Victor diamond mine, located 90 km west of Attawapiskat, Ontario. The North Granny Creek basin is located approximately 3 km from the mine pit and is comprised of several peatland types and forms. The surface hydrology of this area is expected to be affected by groundwater depressurization due to dewatering of the mine pit by deep groundwater pumping wells. Effects of this activity on surface hydrology could possibly include increased soil storage capacity due to drier conditions and decreased melt rates due to reduced inputs of warm groundwater. Surface water connectivity is usually at a maximum in the spring because of a relatively impermeable frost table and low soil storage capacity which reduces infiltration. These effects of melt will not be observed uniformly over the entire catchment because of the

  6. Oxygen-Isotopic Variability Across the 8.2ka Cold Event in an Ombrotrophic Peat bog on the Bonavista Peninsula, Newfoundland

    NASA Astrophysics Data System (ADS)

    Daley, T. J.; Hughes, P. D.; Street-Perrott, F. A.; Loader, N. J.; Barber, K. E.

    2005-12-01

    Ombrotrophic (precipitation-fed) peatlands are well established as sources of proxy-climate information through the Holocene (Aaby, 1974; Barber, 1981; Barber et al., 1994, 1998; Hughes et al., 2000; Charman, 2002). Over the past decade, innovative methodological developments have resulted in the production of multi-proxy records where co-registered signals are used to establish the response of bogs to climatic forcing (Blundell & Barber, 2005, Langdon & Barber, in press; Hughes et al., in press). These techniques have utilised changes in the relative abundance of bog taxa, combined with knowledge of their ecology and the degree of decomposition of the peat, to infer the nature of past environmental changes. Despite the success of this methodology, there remains a need for an approach that is better able to quantify the magnitude of observed climatic changes and which is directly comparable with records from lakes, ice cores and marine sediments. Analysis of the stable isotopes of oxygen and hydrogen in the cellulose of Sphagnum moss offers additional environmentally-sensitive proxies with which to reconstruct isotopic variations in source water (palaeo-precipitation), and hence changes in climate and atmospheric circulation. Sphagnum moss is particularly suited to isotopic analysis by virtue of the comparatively simple pathway that leads from precipitation to cellulose synthesis. We present an oxygen-isotope time series developed from a 2m section of a peat core from Newfoundland (latitude, 49°.150 N, longitude, 53°.583 W). The location of the site on the North east coast of the island makes it particularly sensitive to the atmospheric impact of changes in the nature of the Inner Labrador current, thought to be the conduit that carried the meltwater plume from the Lake Agassiz megaflood (e.g. Keigwin, et al., 2005). The results will be compared with existing multi-proxy data on plant macrofossils, peat humification and testate amoebae derived from the same core

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

    NASA Astrophysics Data System (ADS)

    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

  8. Modeling CH4 and CO2 cycling using porewater stable isotopes in a thermokarst bog in Interior Alaska: results from three conceptual reaction networks

    DOE PAGES

    Neumann, Rebecca B.; Blazewicz, Steven J.; Conaway, Christopher H.; ...

    2015-12-16

    Quantifying rates of microbial carbon transformation in peatlands is essential for gaining mechanistic understanding of the factors that influence methane emissions from these systems, and for predicting how emissions will respond to climate change and other disturbances. In this study, we used porewater stable isotopes collected from both the edge and center of a thermokarst bog in Interior Alaska to estimate in situ microbial reaction rates. We expected that near the edge of the thaw feature, actively thawing permafrost and greater abundance of sedges would increase carbon, oxygen and nutrient availability, enabling faster microbial rates relative to the center ofmore » the thaw feature. We developed three different conceptual reaction networks that explained the temporal change in porewater CO2, CH4, δ13C-CO2 and δ13C-CH4. All three reaction-network models included methane production, methane oxidation and CO2 production, and two of the models included homoacetogenesis — a reaction not previously included in isotope-based porewater models. All three models fit the data equally well, but rates resulting from the models differed. Most notably, inclusion of homoacetogenesis altered the modeled pathways of methane production when the reaction was directly coupled to methanogenesis, and it decreased gross methane production rates by up to a factor of five when it remained decoupled from methanogenesis. The ability of all three conceptual reaction networks to successfully match the measured data indicate that this technique for estimating in-situ reaction rates requires other data and information from the site to confirm the considered set of microbial reactions. Despite these differences, all models indicated that, as expected, rates were greater at the edge than in the center of the thaw bog, that rates at the edge increased more during the growing season than did rates in the center, and that the ratio of acetoclastic to hydrogenotrophic methanogenesis was

  9. U-Pb SHRIMP dating of uraniferous opals

    USGS Publications Warehouse

    Nemchin, A.A.; Neymark, L.A.; Simons, S.L.

    2006-01-01

    U-Pb and U-series analyses of four U-rich opal samples using sensitive high-resolution ion microprobe (SHRIMP) demonstrate the potential of this technique for the dating of opals with ages ranging from several tens of thousand years to millions of years. The major advantages of the technique, compared to the conventional thermal ionisation mass spectrometry (TIMS), are the high spatial resolution (???20 ??m), the ability to analyse in situ all isotopes required to determine both U-Pb and U-series ages, and a relatively short analysis time which allows obtaining a growth rate of opal as a result of a single SHRIMP session. There are two major limitations to this method, determined by both current level of development of ion probes and understanding of ion sputtering processes. First, sufficient secondary ion beam intensities can only be obtained for opal samples with U concentrations in excess of ???20 ??g/g. However, this restriction still permits dating of a large variety of opals. Second, U-Pb ratios in all analyses drifted with time and were only weakly correlated with changes in other ratios (such as U/UO). This drift, which is difficult to correct for, remains the main factor currently limiting the precision and accuracy of the U-Pb SHRIMP opal ages. Nevertheless, an assumption of similar behaviour of standard and unknown opals under similar analytical conditions allowed successful determination of ages with precisions of ???10% for the samples investigated in this study. SHRIMP-based U-series and U-Pb ages are consistent with TIMS dating results of the same materials and known geological timeframes. ?? 2005 Elsevier B.V. All rights reserved.

  10. Ages of 24 widespread tephras erupted since 30,000 years ago in New Zealand, with re-evaluation of the timing and palaeoclimatic implications of the Lateglacial cool episode recorded at Kaipo bog

    NASA Astrophysics Data System (ADS)

    Lowe, David J.; Blaauw, Maarten; Hogg, Alan G.; Newnham, Rewi M.

    2013-08-01

    Tephras are important for the NZ-INTIMATE project because they link all three records comprising the composite inter-regional stratotype developed for the New Zealand climate event stratigraphy (NZ-CES). Here we firstly report new calendar ages for 24 widespread marker tephras erupted since 30,000 calendar (cal.) years ago in New Zealand to help facilitate their use as chronostratigraphic dating tools for the NZ-CES and for other palaeoenvironmental and geological applications. The selected tephras comprise 12 rhyolitic tephras from Taupo, nine rhyolitic tephras from Okataina, one peralkaline rhyolitic tephra from Tuhua, and one andesitic tephra each from Tongariro and Egmont/Taranaki volcanic centres. Age models for the tephras were obtained using three methods: (i) 14C-based wiggle-match dating of wood from trees killed by volcanic eruptions (these dates published previously); (ii) flexible depositional modelling of a high-resolution 14C-dated age-depth sequence at Kaipo bog using two Bayesian-based modelling programs, Bacon and OxCal's P_Sequence function, and the IntCal09 data set (with SH offset correction -44 ± 17 yr); and (iii) calibration of 14C ages using OxCal's Tau_Boundary function and the SHCal04 and IntCal09 data sets. Our preferred dates or calibrated ages for the 24 tephras are as follows (youngest to oldest, all mid-point or mean ages of 95% probability ranges): Kaharoa AD 1314 ± 12; Taupo (Unit Y) AD 232 ± 10; Mapara (Unit X) 2059 ± 118 cal. yr BP; Whakaipo (Unit V) 2800 ± 60 cal. yr BP; Waimihia (Unit S) 3401 ± 108 cal. yr BP; Stent (Unit Q) 4322 ± 112 cal. yr BP; Unit K 5111 ± 210 cal. yr BP; Whakatane 5526 ± 145 cal. yr BP; Tuhua 6577 ± 547 cal. yr BP; Mamaku 7940 ± 257 cal. yr BP; Rotoma 9423 ± 120 cal. yr BP; Opepe (Unit E) 9991 ± 160 cal. yr BP; Poronui (Unit C) 11,170 ± 115 cal. yr BP; Karapiti (Unit B) 11,460 ± 172 cal. yr BP; Okupata 11,767 ± 192 cal. yr BP; Konini (bed b) 11,880 ± 183 cal. yr BP; Waiohau 14,009 ± 155

  11. Radionuclide deposition control

    DOEpatents

    Brehm, William F.; McGuire, Joseph C.

    1980-01-01

    The deposition of radionuclides manganese-54, cobalt-58 and cobalt-60 from liquid sodium coolant is controlled by providing surfaces of nickel or high nickel alloys to extract the radionuclides from the liquid sodium, and by providing surfaces of tungsten, molybdenum or tantalum to prevent or retard radionuclide deposition.

  12. Domestic phosphate deposits

    USGS Publications Warehouse

    McKelvey, V.E.; Cathcart, J.B.; Altschuler, Z.S.; Swanson, R.W.; Lutz, Katherine

    1953-01-01

    Most of the worlds phosphate deposits can be grouped into six types: 1) igneous apatite deposits; 2) marine phosphorites; 3) residual phosphorites; 4) river pebble deposits; 5) phosphatized rock; and 6) guano. The igneous apatites and marine phosphorites form deposits measurable in millions or billions of tons; the residual deposits are measurable in thousands or millions; and the other types generally only in thousands of tons. Igneous apatite deposits have been mined on a small scale in New York, New Jersey, and Virginia. Marine phosphorites have been mined in Montana, Idaho, Utah, Wyoming, Arkansas, Tennessee, North Carolina, South Carolina, Georgia, and Florida. Residual phosphorites have been mined in Tennessee, Pennsylvania, and Florida. River pebble has been produced in South Carolina and Florida; phosphatized rock in Tennessee and Florida; and guano in New Mexico and Texas. Present production is limited almost entirely to Florida, Tennessee, Montana, Idaho, and Wyoming. Incomplete but recently partly revised estimates indicate the presence of about 5 billion tons of phosphate deposits in the United States that is minable under present economic conditions. Deposits too lean in quality or thickness to compete with those in the western and southeastern fields probably contain tens of billions of tons.

  13. Investigation of freshwater sponges spicules deposits in a karstic lake in Brazil.

    PubMed

    Machado, V S; Volkmer-Ribeiro, C; Iannuzzi, R

    2016-02-01

    The environmental conditions which contributed to the formation of the notorious quaternary deposits of freshwater sponge spicules in karstic lentic environments in Brazil have been subject of some speculation. No investigation has yet been conducted to test whether these deposits currently originate in karstic lakes. To provide for such an investigation, Serra Negra Lake, which is formed on an ultramafic-alkaline-carbonatite dome at central western Brazil, close to the area of occurrence of the paleo-deposits was selected for the study. Bottom sediments were sampled at 10 stations across the lake, and water was sampled at five of the stations, in June/2011 (rainy season) and October/2011 (dry season). Analysis of granulometry, organic matter and presence of spicules were carried out in the sediments. Lake water was analysed for the main physical and chemical characteristics. Deposit of spicules was restricted to the northern area of the lake, which is rich in macrophyte. The taxonomic analysis of the spicules indicated the contribution of five sponge species, Dosilia pydanieli, Metania spinata, Radiospongilla amazonensis, Trochospongilla variabilis and Heterorotula fistula, which formed large deposits in neighbouring areas. The high silica concentration, derived from the dome volcanic rocks, constant water level and available substrate are credited for the continuous production of sponges and spicules, confirmed by the rare presence of gemmoscleres. The lake is classed as a minerotrophic fen type of bog with a heavy contribution from the surrounding creeks. Lake sediments are fine with high levels of organic matter and peat, which contributed to the trapping of spicules in the sediments.

  14. Plasma deposition of tungsten

    SciTech Connect

    Greenberg, K.E.

    1986-12-01

    Tungsten films were plasma-deposited using an abnormal glow discharge through a mixture of tungsten hexafluoride, hydrogen, and argon. The films adhered well to silicon, silicon dioxide, gallium arsenide, and aluminum substrates placed directly on the discharge cathode. Typical deposition rates were on the order of 160 Angstroms/minute with as-deposited film resistivities of 40 to 70 microohm-cm. The tungsten was analyzed using a number of techniques including x-ray diffraction, scanning electron microscopy, and Auger spectroscopy. Low-resistivity (<10 microohm-cm) films that adhered well to silicon dioxide were obtained with a two-step process utilizing plasma deposition and conventional chemical vapor deposition.

  15. Stratiform chromite deposit model

    USGS Publications Warehouse

    Schulte, Ruth F.; Taylor, Ryan D.; Piatak, Nadine M.; Seal, Robert R., II

    2010-01-01

    Stratiform chromite deposits are of great economic importance, yet their origin and evolution remain highly debated. Layered igneous intrusions such as the Bushveld, Great Dyke, Kemi, and Stillwater Complexes, provide opportunities for studying magmatic differentiation processes and assimilation within the crust, as well as related ore-deposit formation. Chromite-rich seams within layered intrusions host the majority of the world's chromium reserves and may contai