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Sample records for bog north estonia

  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. Simulation of the hydrogeologic effects of oil-shale mining on the neighbouring wetland water balance: case study in north-eastern Estonia

    NASA Astrophysics Data System (ADS)

    Marandi, Andres; Karro, Enn; Polikarpus, Maile; Jõeleht, Argo; Kohv, Marko; Hang, Tiit; Hiiemaa, Helen

    2013-11-01

    The water balance of wetlands plays an integral role in their function. Developments adjacent to wetlands can affect their water balance through impacts on groundwater flow and increased discharge in the area, and they can cause lowering of the wetland water table. A 430 km2 area was selected for groundwater modelling to asses the effect of underground mining on the water balance of wetlands in north-eastern Estonia. A nature conservation area (encompassing Selisoo bog) is within 3 km of an underground oil-shale mine. Two future mining scenarios with different areal extents of mining were modeled and compared to the present situation. Results show that the vertical hydraulic conductivity of the subsurface is of critical importance to potential wetland dewatering as a result of mining. Significant impact on the Selisoo bog water balance will be caused by the approaching mine but there will be only minor additional impacts from mining directly below the bog. The major impact will arise before that stage, when the underground mine extension reaches the border of the nature conservation area; since the restriction of activities in this area relates to the ground surface, the conservation area’s border is not sufficiently protective in relation to underground development.

  3. 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

  4. 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. PMID:25998635

  5. 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...

  6. 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 ...

  7. 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...

  8. 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.

  9. 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)

  10. Astronomy in the society and culture of Estonia

    NASA Astrophysics Data System (ADS)

    Leedjärv, Laurits

    2011-06-01

    History and present state of astronomy in a small North-Eastern European country are considered. There is a rather big number (about 35) of professional astronomers in Estonia, including 21 IAU members. Through some outstanding persons, astronomy in Estonia has significant relations with the society. The same can be said about the culture. Well-developed astronomy has contributed into the cooperation of Estonia with the European Space Agency, and thus, has an indirect effect to the country's economy.

  11. Peat Bog Wildfire Smoke Exposure in Rural North Carolina Is Associated with Cardiopulmonary Emergency Department Visits Assessed through Syndromic Surveillance

    PubMed Central

    Stone, Susan L.; Cascio, Wayne E.; Neas, Lucas M.; Kilaru, Vasu J.; Carraway, Martha Sue; Szykman, James J.; Ising, Amy; Cleve, William E.; Meredith, John T.; Vaughan-Batten, Heather; Deyneka, Lana; Devlin, Robert B.

    2011-01-01

    Background: In June 2008, burning peat deposits produced haze and air pollution far in excess of National Ambient Air Quality Standards, encroaching on rural communities of eastern North Carolina. Although the association of mortality and morbidity with exposure to urban air pollution is well established, the health effects associated with exposure to wildfire emissions are less well understood. Objective: We investigated the effects of exposure on cardiorespiratory outcomes in the population affected by the fire. Methods: We performed a population-based study using emergency department (ED) visits reported through the syndromic surveillance program NC DETECT (North Carolina Disease Event Tracking and Epidemiologic Collection Tool). We used aerosol optical depth measured by a satellite to determine a high-exposure window and distinguish counties most impacted by the dense smoke plume from surrounding referent counties. Poisson log-linear regression with a 5-day distributed lag was used to estimate changes in the cumulative relative risk (RR). Results: In the exposed counties, significant increases in cumulative RR for asthma [1.65 (95% confidence interval, 1.25–2.1)], chronic obstructive pulmonary disease [1.73 (1.06–2.83)], and pneumonia and acute bronchitis [1.59 (1.07–2.34)] were observed. ED visits associated with cardiopulmonary symptoms [1.23 (1.06–1.43)] and heart failure [1.37 (1.01–1.85)] were also significantly increased. Conclusions: Satellite data and syndromic surveillance were combined to assess the health impacts of wildfire smoke in rural counties with sparse air-quality monitoring. This is the first study to demonstrate both respiratory and cardiac effects after brief exposure to peat wildfire smoke. PMID:21705297

  12. Factors affecting re-vegetation dynamics of experimentally restored extracted peatland in Estonia.

    PubMed

    Karofeld, Edgar; Müür, Mari; Vellak, Kai

    2016-07-01

    Increasing human activity continues to threaten peatlands, and as the area of natural mires declines, our obligation is to restore their ecosystem functions. Several restoration strategies have been developed for restoration of extracted peatlands, including "The moss layer transfer method", which was initiated on the Tässi extracted peatland in central Estonia in May 2012. Three-year study shows that despite the fluctuating water table, rainfall events can compensate for the insufficient moisture for mosses. Total plant cover on the restoration area attained 70 %, of which ~60 % is comprised of target species-Sphagnum mosses. From restoration treatments, spreading of plant fragments had a significant positive effect on the cover of bryophyte and vascular plants. Higher water table combined with higher plant fragments spreading density and stripping of oxidised peat layer affected positively the cover of targeted Sphagnum species. The species composition in the restoration area became similar to that in the donor site in a natural bog. Based on results, it was concluded that the method approved for restoration in North America gives good results also in the restoration of extracted peatland towards re-establishment of bog vegetation under northern European conditions. PMID:26490883

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

    NASA Astrophysics Data System (ADS)

    Magnan, G.; Garneau, M.

    2013-12-01

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

  14. 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

    's approach. Our study site was Mannikjarve, a raised bog located centrally in Estonia and part of the larger Endla Nature Reserve. The size of the bog is approximately 2 km2. Mannikjarve is characterized by a surface pattern of different microtopes consisting of ridge-pool, hollow-ridge, hummock-hollow, Sphagnum lawn, and margin forest. We created a flow-net based on the raised bogs surface elevation. This flow-net defines the direction of lateral flow in the acrotelm. Based on the flow-net we divided the bog into sub-catchments representing the area contributing to discharge at the outlets of the bog. The measured discharge was used in a double mass analysis to calculate discharge ratio's. We assume that changes in discharge ratio's can be relate to changes in contributing area as a result of variable water flow paths. Furthermore, we compared the measured discharges with calculated discharge according to Ingram's model. Based on several reasonable estimates for input parameters, the observed discharges cannot be reproduced with the Ingram model. Furthermore, discharge ratio's between different sub-catchments within the peatland appear to be not constant over time, thus suggesting a shift in water divides that depends on atmospheric events.

  15. 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)

  16. 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.

  17. Biobanking in Estonia.

    PubMed

    Keis, Aime

    2016-03-01

    Estonia is a democratic, parliamentary republic with a health care system that is built on the principle of compulsory, solidarity-based insurance and the all-round availability of services of private service providers. Estonia has specific biobank legislation as well as oversight via data protection laws. Its population-based biobank, the Estonian Genome Center (EGCUT), established in 2001, is one of the largest biobanks in Europe, and its database may be used only for scientific research, public health research, and statistics. The EGCUT can issue data to a third party, but only in coded form. This comprehensive database of genotypic, phenotypic, health, and genealogical information represents about 5% of Estonia's adult population, and is the largest cohort ever gathered in Estonia. Government approval is required for international data sharing, and sharing can be further limited by the requirement of ethics approval and permission from Estonian government. PMID:27256120

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

    PubMed

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

    2009-10-15

    Lead pollution history over Northern Poland was reconstructed for the last ca. 1300 years using the elemental and Pb isotope geochemistry of a dated Polish peat bog. The data show that Polish Pb-Zn ores and coal were the main sources of Pb, other heavy metals and S over Northern Poland up until the industrial revolution. After review of the potential mobility of each element, most of the historical interpretation was based on Pb and Pb isotopes, the other chemical elements (Zn, Cu, Ni, S) being considered secondary indicators of pollution. During the last century, leaded gasoline also contributed to anthropogenic Pb pollution over Poland. Coal and Pb-Zn ores, however, remained important sources of pollution in Eastern European countries during the last 50 years, as demonstrated by a high (206)Pb/(207)Pb ratio (1.153) relative to that of Western Europe (ca. 1.10). The Pb data for the last century were also in good agreement with modelled Pb inventories over Poland and the Baltic region. PMID:19683332

  19. Drumlins of Estonia

    NASA Astrophysics Data System (ADS)

    Rõuk, Aarend-Mihkel; Raukas, Anto

    1989-05-01

    Drumlins, megaflutings and other subglacial streamlined forms, highly variable in shape and size, are widely distributed in Estonia as well as on the bottom of the Gulf of Finland, which was also affected by continental ice. Their total number amounts to 1000. The main drumlin fields are most common in Central Estonia on lateral slopes of bedrock uplands and/or in depressions between them, and they serve as a transitional landscape type between predominantly erosional (in northern Estonia) and depositional zones (in southern Estonia) of the Scandinavian ice sheet. Nevertheless, the local details of bedrock topography and glacial and deglacial history have led to some deviations (e.g. the unique Saadjärv field of big drumlins and megaflutings is situated in a "glacier shadow", on the lee side of a bedrock upland). Being of varied composition and age, drumlins and related streamlined forms represent complex interactions between erosional, transporting and depositional processes, although the dynamics of their formation are still somewhat enigmatic. It seems that in Estonia drumlins were formed both during ice advances and retreats. In some cases there are moraine hillocks, kames and eskers and other ice disintegration features superimposed on drumlins.

  20. Mitigation analysis for Estonia

    SciTech Connect

    Martins, A.; Roos, J.; Pesur, A.

    1996-09-01

    The present report provides data on the mitigation analysis of Estonia. The results for energy, forest and agricultural sectors and macro-economic analysis are given. The Government of Estonia has identified the development of energy production as the main strategical means in the movement towards market economy. Now 99% of electricity generation and about 25% of heat production in Estonia is based on oil shale combustion. To increase the efficiency of oil shale-fired power plants and decrease CO{sub 2} emissions, the State Enterprise (SE) Eesti Energia (Estonian Energy) is planning to reconstruct these power plants and introduce the Circulating Fluidized Bed (CFB) combustion technology for oil shale burning to replace the Pulverized Combustion (PC). According to the Estonian Forest Policy, two general objectives are of importance: sustainability in forestry and efficiency in forest management. For the reduction of greenhouse gases (GHG) emissions from agriculture, it is necessary to increase the efficiency of production resource usage. The growth of the GDP in 1995 was 2.9% as a result of large-scale privatization activities in Estonia and re-introduction of the available, but unused production capacities with the help of foreign and domestic investments. It is assumed that the medium growth rate of GDP reaches 6% in 1998.

  1. Ecology and hydrology of pristine and cutover lowland raised bogs: relationships and implications for restoration

    NASA Astrophysics Data System (ADS)

    Labadz, Jillian; Hart, Roger; Robbins, Jane; Butcher, David; Topliss, David

    2013-04-01

    This paper will examine relationships in vegetation communities and hydrological conditions on areas of lowland raised bog in north west England, comparing damaged and relatively intact sites on two adjacent bogs in Cumbria. Walton Moss is a relatively pristine site whilst and Bolton Fell Moss has a small nature reserve area with remnant vegetation which is surrounded by commercial peat cutting. The intended outcome is to provide a mechanism to inform management decisions, with a view to assisting in the long-term protection and rehabilitation of lowland raised bogs.

  2. 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.

  3. Country report: Estonia

    NASA Astrophysics Data System (ADS)

    Kaasik, Helle

    2015-12-01

    The situation of women in education, work, and research in Estonia is relatively good. Nevertheless, science (especially engineering) remains a male-dominated field. The total number of female scientists and engineers in the workforce is about two-thirds that of males. Moreover, the gender imbalance in the researcher population increases with age. Significant pay-gap and power imbalances between the genders remain both in Estonian society in general and in the fields of science and technology. In many practical situations, behavior of both men and women is still guided by gender stereotypes.

  4. The north-eastern aeolian 'European Sand Belt' as potential record of environmental changes: A case study from Eastern Latvia and Southern Estonia

    NASA Astrophysics Data System (ADS)

    Kalińska-Nartiša, Edyta; Thiel, Christine; Nartišs, Māris; Buylaert, Jan-Pieter; Murray, Andrew S.

    2016-09-01

    The Latvian and Estonian inland dunes belong to the north-eastern part of the 'European Sand Belt' (ESB). These dunes are widely distributed over broad glaciolacustrine plains and Late Glacial alluvial deltas, considered to be potential sources for the aeolian material. Little is known about these aeolian sediments and their substratum; here we present a detailed sedimentary structural and textural characterisation together with a luminescence-based chronology. Through a comparison between grain-size, rounding of quartz grains and surface characteristics in medium/coarse (0.5-0.8 mm) sand, and the light mineral content, we found an alternation of aeolian and periglacial components. Further, short-lasting aeolian abrasion and/or transportation periods, and a significant contribution of a nearby sediment source are suggested. Luminescence dating points to aeolian sand accumulation and dune formation between ∼16 ka and ∼9 ka. However, we also observed some presumably watertable controlled environmental conditions at ∼13 ka; this corresponds with the occurrence of an ice-dammed/proglacial lake.

  5. Estonia: health system review.

    PubMed

    Lai, Taavi; Habicht, Triin; Kahur, Kristiina; Reinap, Marge; Kiivet, Raul; van Ginneken, Ewout

    2013-01-01

    This analysis of the Estonian health system reviews recent developments in organization and governance, health financing, health-care provision, health reforms and health system performance. Without doubt, the main issue has been the 2008 financial crisis. Although Estonia has managed the downturn quite successfully and overall satisfaction with the system remains high, it is hard to predict the longer-term effects of the austerity package. The latter included some cuts in benefits and prices, increased cost sharing for certain services, extended waiting times, and a reduction in specialized care. In terms of health outcomes, important progress was made in life expectancy, which is nearing the European Union (EU) average, and infant mortality. Improvements are necessary in smoking and alcohol consumption, which are linked to the majority of avoidable diseases. Although the health behaviour of the population is improving, large disparities between groups exist and obesity rates, particularly among young people, are increasing. In health care, the burden of out-of-pocket payments is still distributed towards vulnerable groups. Furthermore, the number of hospitals, hospital beds and average length of stay has decreased to the EU average level, yet bed occupancy rates are still below EU averages and efficiency advances could be made. Going forwards, a number of pre-crisis challenges remain. These include ensuring sustainability of health care financing, guaranteeing a sufficient level of human resources, prioritizing patient-centred health care, integrating health and social care services, implementing intersectoral action to promote healthy behaviour, safeguarding access to health care for lower socioeconomic groups, and, lastly, improving evaluation and monitoring tools across the health system. PMID:24334730

  6. Directional distribution of chilling winds in Estonia

    NASA Astrophysics Data System (ADS)

    Saue, Triin

    2015-11-01

    Wind chill equivalent temperature (WCET) is used to define thermal discomfort in winter months. Directional distributions of winds, which are associated with uncomfortable weather, were composed of three climatologically different Estonian locations: Vilsandi, Kuusiku, and Jõhvi. Cases with wind chill equivalent temperature <-10 °C, which could be classified as "uncomfortable or worse," were investigated. Additional thresholds were used to measure weather risk. The 25th percentile of daily minimum WCET was tested to measure classical prevalent wind directions in Estonia: W, SW, and NW bring warm air in winter from the North Atlantic, while winds from the East-European plain (NE, E, and SE) are associated with cold air. The eastern prevalence was stronger when a lower threshold was used. A directional approach may find several applications, such as building, agricultural, landscape, or settlement planning.

  7. Directional distribution of chilling winds in Estonia

    NASA Astrophysics Data System (ADS)

    Saue, Triin

    2016-08-01

    Wind chill equivalent temperature (WCET) is used to define thermal discomfort in winter months. Directional distributions of winds, which are associated with uncomfortable weather, were composed of three climatologically different Estonian locations: Vilsandi, Kuusiku, and Jõhvi. Cases with wind chill equivalent temperature <-10 °C, which could be classified as "uncomfortable or worse," were investigated. Additional thresholds were used to measure weather risk. The 25th percentile of daily minimum WCET was tested to measure classical prevalent wind directions in Estonia: W, SW, and NW bring warm air in winter from the North Atlantic, while winds from the East-European plain (NE, E, and SE) are associated with cold air. The eastern prevalence was stronger when a lower threshold was used. A directional approach may find several applications, such as building, agricultural, landscape, or settlement planning.

  8. Directional distribution of chilling winds in Estonia.

    PubMed

    Saue, Triin

    2016-08-01

    Wind chill equivalent temperature (WCET) is used to define thermal discomfort in winter months. Directional distributions of winds, which are associated with uncomfortable weather, were composed of three climatologically different Estonian locations: Vilsandi, Kuusiku, and Jõhvi. Cases with wind chill equivalent temperature <-10 °C, which could be classified as "uncomfortable or worse," were investigated. Additional thresholds were used to measure weather risk. The 25th percentile of daily minimum WCET was tested to measure classical prevalent wind directions in Estonia: W, SW, and NW bring warm air in winter from the North Atlantic, while winds from the East-European plain (NE, E, and SE) are associated with cold air. The eastern prevalence was stronger when a lower threshold was used. A directional approach may find several applications, such as building, agricultural, landscape, or settlement planning. PMID:26585350

  9. A Connecticut Yankee in Estonia.

    ERIC Educational Resources Information Center

    Scahill, Edward M.

    1998-01-01

    Compares the real incomes of U.S. and Estonian workers using a procedure from Mark Twain's "A Connecticut Yankee in King Arthur's Court." Argues that the application of Twain's logic to the recent economic development of Estonia provides a colorful approach to teaching economic issues. (DSK)

  10. 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

  11. 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.

  12. 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.

  13. 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

  14. 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.

  15. 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

  16. Estonia--Going Home Again: Returning to the Roots.

    ERIC Educational Resources Information Center

    Pedak-Kari, Maria

    This paper provides background on The National Library of Estonia (NLE), discusses a fellowship project for developing the National Library, and presents the impressions of the author, an Estonian American, who traveled to Estonia. The NLE looks to the West for automation, information, and institutional modeling. The NLE is Estonia's equivalent of…

  17. Interdisciplinary research at the SMEAR Estonia station

    NASA Astrophysics Data System (ADS)

    Noe, Steffen M.; Niinemets, Ülo; Kangur, Ahto; Hõrrak, Urmas; Soosaar, Kaido; Mander, Ülo

    2014-05-01

    Interdisciplinary research on ecosystem-atmosphere relations has been an issue since many years in Estonia. Since 2008, these activities have been intensified and led to the build up of a SMEAR (Station for Measuring Ecosystem-Atmosphere Relations) type station in Estonia. It is part of the Estonian Environmental Observatory, a delocalized research infrastructure that is operated by several Estonian universities and research institutions. It's core is located in the experimental forestry district in Järvselja where a major portion of the ecosystem and atmospheric research activities take place. Here, we present an overview of the current state of research which especially takes care of the hemiboreal forest ecosystem. Continuous build up of comprehensive measurements at diverse sites has led to a network of stations over Estonia. It's location in the transition zone between boreal and temperate forest ecosystems allows for new and updated hypothesis regarding fluxes of energy and matter in a globally changing climate system.

  18. 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.

  19. 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.

  20. 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.

  1. Factors Controlling Diffusive CO2 Transport and Production in the Cedarburg Bog, Saukville, Wisconsin: Field Observations

    NASA Astrophysics Data System (ADS)

    Joynt, E.; Han, W. S.; Gulbranson, E. L.; Graham, J. P.

    2015-12-01

    Wetland ecosystems are vital components of the carbon cycle containing an estimated 20-30% of the global soil carbon store. The Cedarburg Bog of southeastern Wisconsin boasts a myriad of wetland habitats including the southernmost string bog found in North America. The behavior of carbon dioxide (CO2) in these systems is the response of multiple interdependent variables that are, collectively, not well understood. Modeling this behavior in future climate scenarios requires detailed representation of such relationships within highly diverse environments. In 2014 a LI-COR 8100A automated soil gas flux system was installed in a hollow of the Cedarburg Bog string bog and collectively measured diffusive CO2 concentration and flux. Supplemental groundwater data, soil temperature, and weather data (temperature, pressure, precipitation, etc.) were also included to elucidate correlations between soil CO2 flux/CO2 concentration and external forces. In 2015 field data were complemented with soil moisture data and depth profile sampling of pore water chemistry and stable carbon isotopes from peat and gaseous media in order to discern the source and evolution of CO2 at depth. Preliminary LI-COR data analysis reveals distinct diurnal and seasonal trends; CO2 concentration builds overnight while flux increases during the day, both peaking in mid-summer. Flux events average 405 mg CO2/m2 per hour but reach over 31,800 mg CO2/m2 per hour in a single event and in several instances negative flux events are observed. Correlation significance also yields a wide array of strengths among variables. Initial δ13C data from gaseous CO2 infer, on average, a more positive δ13C signature in the atmosphere compared to the surface and shallow subsurface. Temporal trends of these parameters are similar to one another, becoming depleted in δ13C through time. Further interpretation of data trends will utilize the HYDRUS-1D model to quantify relationships under changing environmental conditions.

  2. Climate change scenarios and the effect of sea-level rise for Estonia

    NASA Astrophysics Data System (ADS)

    Kont, Are; Jaagus, Jaak; Aunap, Raivo

    2003-03-01

    Climate warming due to the enhanced greenhouse effect is expected to have a significant impact on natural environment and human activity in high latitudes. Mostly, it should have a positive effect on human activity. The main threats in Estonia that could be connected with sea-level rise are the flooding of coastal areas, erosion of sandy beaches and the destruction of harbour constructions. Possible climate change and its negative impacts in the coastal regions of Estonia are estimated in this paper. Climate change scenarios for Estonia were generated using a Model for the Assessment of Greenhouse-gas Induced Climate Change (MAGICC) and a regional climate change database—SCENanario GENerator (SCENGEN). Three alternative emission scenarios were combined with data from 14 general circulation model experiments. Climate change scenarios for the year 2100 indicate a significant increase in air temperature (by 2.3-4.5 °C) and precipitation (by 5-30%) in Estonia. The highest increase is expected to take place during winter and the lowest increase in summer. Due to a long coastline (3794 km) and extensive low-lying coastal areas, global climate change through sea-level rise will strongly affect the territory of Estonia. A number of valuable natural ecosystems will be in danger. These include both marine and terrestrial systems containing rare plant communities and suitable breeding places for birds. Most sandy beaches high in recreational value will disappear. However, isostatic land uplift and the location of coastal settlements at a distance from the present coastline reduce the rate of risk. Seven case study areas characterising all the shore types of Estonia have been selected for sea-level rise vulnerability and adaptation assessment. Results and estimates of vulnerability to 1.0-m sea-level rise by 2100 are presented in this paper. This is the maximum scenario according to which the actually estimated relative sea-level rise would vary from 0.9 m (SW Estonia) to 0

  3. 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

  4. 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

  5. OECD Reviews of School Resources: Estonia

    ERIC Educational Resources Information Center

    Santiago, Paulo; Levitas, Anthony; Radó, Péter; Shewbridge, Claire

    2016-01-01

    This report for Estonia forms part of the OECD Review of Policies to Improve the Effectiveness of Resource Use in Schools. The purpose of the review is to explore how school resources can be governed, distributed, utilised and managed to improve the quality, equity and efficiency of school education. School resources are understood in a broad way,…

  6. Stakeholder Perspectives: CLIL Programme Management in Estonia

    ERIC Educational Resources Information Center

    Mehisto, Peeter; Asser, Hiie

    2007-01-01

    In 2000, Estonia launched a voluntary Estonian language CLIL programme for seven year-olds in four Russian-medium schools. The programme has expanded rapidly to a total of 48 kindergartens and schools. This paper reports on research into stakeholder perspectives on programme management. In addition to surveying parents, teachers, vice-principals…

  7. Current and historical record of indium deposition from the atmosphere to an ombrotrophic bog in northeastern United States

    NASA Astrophysics Data System (ADS)

    White, S. O.; Keach, C.; Hemond, H.

    2012-12-01

    The industrial production of indium is increasing dramatically due to new uses in the rapidly growing electronics, photovoltaic, and LED industries. Little is known, however, about the natural or industrial cycling of indium or its environmental behavior, despite the fact that industrial emissions to the atmosphere appear to have already exceeded natural emissions. The history of metal deposition from the atmosphere is often reflected in the vertical profiles of the metals in ombrotrophic bogs, which by definition do not receive surface or subsurface runoff. Analysis of a peat core obtained using a novel freeze corer at Thoreau's Bog in Concord, MA shows that the rate of indium deposition to the bog increased beginning in the early 1900s, peaked in the early 1970s, and then decreased dramatically to pre-1900 values by the present time. This profile is counter to the pattern of indium's industrial use, which has increased only in the past 30-40 years. The profile coincides well, however, with the estimated history of particulate emissions from smelting and from coal combustion in North America. Back-trajectory analysis suggests that smelting was the dominant source of atmospheric particles with high indium concentrations deposited to the bog. This study suggests that metal smelting and coal burning are currently indium's primary industrial environmental sources. While releases from the semiconductor and electronics industries are comparatively small at present, this scenario may change with the rapid growth of indium use in these industries.

  8. High Summer Temperatures and Mortality in Estonia

    PubMed Central

    Oudin Åström, Daniel; Åström, Christofer; Rekker, Kaidi; Indermitte, Ene; Orru, Hans

    2016-01-01

    Background On-going climate change is predicted to result in a growing number of extreme weather events—such as heat waves—throughout Europe. The effect of high temperatures and heat waves are already having an important impact on public health in terms of increased mortality, but studies from an Estonian setting are almost entirely missing. We investigated mortality in relation to high summer temperatures and the time course of mortality in a coastal and inland region of Estonia. Methods We collected daily mortality data and daily maximum temperature for a coastal and an inland region of Estonia. We applied a distributed lag non-linear model to investigate heat related mortality and the time course of mortality in Estonia. Results We found an immediate increase in mortality associated with temperatures exceeding the 75th percentile of summer maximum temperatures, corresponding to approximately 23°C. This increase lasted for a couple of days in both regions. The total effect of elevated temperatures was not lessened by significant mortality displacement. Discussion We observed significantly increased mortality in Estonia, both on a country level as well as for a coastal region and an inland region with a more continental climate. Heat related mortality was higher in the inland region as compared to the coastal region, however, no statistically significant differences were observed. The lower risks in coastal areas could be due to lower maximum temperatures and cooling effects of the sea, but also better socioeconomic condition. Our results suggest that region specific estimates of the impacts of temperature extremes on mortality are needed. PMID:27167851

  9. Background Study on Employment and Labour Market in Estonia.

    ERIC Educational Resources Information Center

    Eamets, Raul; Philips, Kaia; Annus, Tiina

    During the years 1989-1997 in Estonia, employment has decreased; unemployment and inactivity have increased. Females have tended to move to inactivity while males have become unemployed. The wage patterns are very flat relative to those in market economies. Estonia has opted for very low levels of unemployment benefits, pensions, and a low minimum…

  10. Ecological catastrophe in connection with the impact of the Kaali Meteorite about 800-400 BC on the island of Saaremaa, Estonia

    NASA Astrophysics Data System (ADS)

    Veski, Siim; Heinsalu, Atko; Kirsimäe, Kalle; Poska, Anneli; Saarse, Leili

    2001-10-01

    A sequence of peat enriched with impact ejecta (allochthonous minerals and iridium) from Piila bog, 6 km away from the Kaali impact crater (island of Saaremaa, Estonia), was examined using pollen, radiocarbon, loss-on-ignition, and x-ray diffraction analyses to date and assess the environmental effect of the impact. The vegetation in the surroundings of the Piila bog before the Kaali impact was a fen surrounded by forest in natural conditions. Significant changes occur in pollen accumulation and composition of pollen in the depth interval 170-178 cm, which contains above background values of iridium (up to 0.53 ppb). Two samples from the basal silt layer inside the main crater at Kaali contain 0.8 ppb of iridium, showing that iridium was present in the impact ejecta. The impact explosion swept the surroundings clean of forest shown by the threefold decrease in the total pollen influx (especially tree pollen influx), increase in influx and diversity of herb taxa, and the relative dominance of pine. Increased input of mineral matter measured by loss-on-ignition and the composition mineral matter (increased input of allochthonous minerals) together with an extensive layer of charcoal and wood stumps in Piila bog at the same depth interval points to an ecological catastrophe, with local impact-induced wildfires reaching at least 6 km northwest of the epicenter. The disappearance of cereals in the pollen record suggests that farming, cultivation and possibly human habitation in the region ceased for a period of ~100 years. The meteorite explosion at Kaali ranged between the effects of Hiroshima and Tunguska. The age of the Kaali impact event is placed between 800-400 b.c. based on radiocarbon dating of the peat enriched with impact ejecta in the Piila bog.

  11. Atmospheric Feedbacks By Greenhouse Gases From Baltic Bogs During Late Holocene Reconstructed Using Wetness Anomalies

    NASA Astrophysics Data System (ADS)

    Alm, J.; Sillasoo, Ü.; Endjärv, E.; Lode, E.; Blundell, A.; Charman, D.; Väliranta, M.; Laine, J. K.; Tuittila, E.; Seppä, H.; Korhola, A.; Karofeld, E.

    2006-12-01

    Climate changes are documented in multiple proxies in sediments such as peat. At the same time, information on ecosystem feedbacks in terms of greenhouse gas balances can be derived from the proxies. As part of the EU-project ACCROTELM, we headed to building peat-based multi-proxy datasets from Finnish and Estonian sites over the past 4500 years. The cores were 14C-dated using AMS, and the high resolution age-depth curves were assumed by wiggle matching. We sampled the peat cores with a resolution of 1 cm at least every at 4th cm and analyzed plant macrofossils, testate amoebae, and carbon accumulation rates. At least a decadal resolution was obtained for the 1 cm sample slices throughout the cores. We also sampled current testate amoebae communities at different microsites of vegetation varying in moisture conditions, in order to compile a transfer function for water tables. These reconstructions were attributed with spatial proportions of mire microsites, derived in GIS from aerial images. We reviewed the methane emission and carbon accumulation history of the bog landscape as GWP using the time series of GHG balances over the 4,5 millennia. Special attention was paid for the periods of rapid climatic excursions with wet or dry shifts. The climatic feedbacks, i.e. CO2 deposition from bulk density and C content, and CH4 modeled as function of wetness, were combined in CO2 equivalents. Although the bogs were carbon sinks, the apparent impact was net atmospheric warming, through the dynamics of CH4 release. Burning of peat in the fires located in the sediment cores must have increased the net warming effect. The temporal correlations between the bogs south and north from the Gulf of Finland are inspected.

  12. 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

  13. 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.

  14. 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

  15. GHG emissions from temperate lowland bog under contrasting land use: insights from the Defra Lowland Bog Project.

    NASA Astrophysics Data System (ADS)

    Worrall, Fred; dIXON, Simon

    2015-04-01

    The Defra lowland peat project was established 3 years ago in response to the estimation that while lowland peat soils represent only 15% of the area of UK peat they represented 75% of the greenhouse gas emissions. The study has considered a range of settings, including: restored raised bog; extracted bare peat; and peat soil converted for arable. The sites were instrumented to cover as complete a range of greenhouse gases as possible and this included N2O as well as fluvial carbon fluxes. This talk will review results with particular emphasis on problems of understanding fluvial carbon fluxes from lowland raised bogs where flow directions are complex.

  16. Carbon dynamics in peat bogs: Insights from substrate macromolecular chemistry

    NASA Astrophysics Data System (ADS)

    Kuder, Tomasz; Kruge, Michael A.

    2001-09-01

    The macromolecular compositions of subfossil plants from boreal Sphagnum bogs and restiad bogs (New Zealand) have been studied by pyrolysis-gas chromatography/mass spectrometry to evaluate the extent of degradation in the anoxic zone (catotelm) of a peat bog. Degradation of vascular plant polysaccharides was apparent only into the upper catotelm. Sphagnum was degraded more slowly than vascular plants, but no cessation of degradation was observed. The inferred rate of degradation varied depending on type of plant, extent of aerobic, precatotelmic degradation, and mode of litter deposition (rooting versus at the surface). Environmental forcing on anaerobic carbon dynamics would potentially be largest if the hydrology was disturbed at a wet and vascular plant-rich site. Peat deposited under a dry regime would be relatively inert in anaerobic conditions. Although catotelmic degradation is usually not extensive, in some cases, if labile organic matter is retained in the aerobic phase (e.g., restiad bogs) a major fraction of peat is degraded in catotelm, potentially resulting in a delayed major export of 14C-old methane.

  17. 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.

  18. International Reports on Literacy Research: Estonia, Hungary, and Bulgaria.

    ERIC Educational Resources Information Center

    Eakle, A. Jonathan, Comp.; Garber, Andrew M., Comp.

    2003-01-01

    Presents part of a series that highlights this journal's interest in informing readers of international literacy research beyond what appears in featured articles. Discusses reports on literacy research in Estonia, Hungary, and Bulgaria. (SG)

  19. 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. PMID:26846473

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

    NASA Astrophysics Data System (ADS)

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

    2011-12-01

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

  1. 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. PMID:26868586

  2. 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.

  3. Bioerosion of Inorganic Hard Substrates in the Ordovician of Estonia (Baltica)

    PubMed Central

    Vinn, Olev; Wilson, Mark A.; Toom, Ursula

    2015-01-01

    The earliest bioeroded inorganic hard substrates in the Ordovician of Estonia appear in the Dapingian. Hardgrounds are also known from the Sandbian and Katian. Most of the bioerosion of inorganic hard substrates occurs as the boring Trypanites Mägdefrau, 1932 along with some possible Gastrochaenolites borings. North American hardground borings are more diverse than those in Baltica. In contrast to a worldwide trend of increasing boring intensity, the Estonian record seems to show no increase in boring intensities during the Middle and Late Ordovician. Hardgrounds seem to be more common during the temperate climate interval of the Ordovician calcite sea in Estonia (seven hardgrounds during 15 my) than in the part with a tropical climate (four hardgrounds during 12 my). Bioerosion is mostly associated with carbonate hardgrounds, but cobbles and pebbles broken from the hardgrounds are also often penetrated by Trypanites borings. The general diversity of boring ichnotaxa in Baltica increased from one ichnospecies in the Cambrian to seven by the end of Ordovician, showing the effect of the GOBE on bioeroding ichnotaxa. The diversity of inorganic hard substrate borers increased by only two times. This difference can be explained by the wider environmental distribution of organic as compared to inorganic substrates in the Ordovician seas of Baltica, and their more continuous temporal availability, which may have caused increased specialization of several borers. The inorganic substrates may have been bioreroded only by the generalists among boring organisms. PMID:26218582

  4. Stable isotope record of Holocene precipitation changes from Lake Nuudsaku in southern Estonia

    NASA Astrophysics Data System (ADS)

    Fortney, Carolyn; Stansell, Nathan; Klein, Eric; Terasmaa, Jaanus; Dodd, Justin

    2015-04-01

    Radiocarbon dated, finely laminated lake sediments record Holocene precipitation changes from southern Estonia. Modern water isotope data suggest that Lake Nuudsaku is a mostly open system that is primarily fed by winter precipitation and groundwater, and summer precipitation plays only a secondary role in the overall hydrologic balance. Initial results indicate that changes in insolation likely drove the overall Holocene pattern with relatively wet conditions during the early Holocene, followed by arid conditions during the middle Holocene and a return to wetter conditions during the late Holocene. However, there is pronounced millennial and centennial-scale variability that cannot be explained by insolation forcing alone. Notably, there is a trend toward wetter conditions from ~4.0 to 2.0 ka, followed by a trend toward drier conditions during the last 2 millennia. This late Holocene pattern diverges from the pattern observed in records from north-central Estonia that suggest an overall trend of wetter conditions for the last ~4 ka. These initial results thus indicate that the Lake Nuudsaku sediments have the potential to yield a unique near-annual to decade-scale record of past precipitation changes from the southern Baltic region.

  5. 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.

  6. 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.

  7. 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.

  8. New Investigations of the Alleged Meteorite from Igast, Estonia

    NASA Technical Reports Server (NTRS)

    OKeefe, John A.; Lowman, Paul D., Jr.

    1961-01-01

    This paper presents the results of a reinvestigation of the object which allegedly fell at Igast, Estonia, in 1855, and which may be the only example of a meteorite with the chemical composition of a tektite. R is concluded that generally quoted opinions of the artificial nature of this object are based on spurious samples, specifically melted brick and quartz basalt porphyry distributed by a Russian collector. Possibly genuine specimens from this observed fall are in the British Museum, the Paris Museum, and perhaps at the University of Dorpat, Estonia. It is recommended that these specimens be re-examined and that a search for similar objects be made.

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

    PubMed Central

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

    2012-01-01

    Abstract 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. PMID:22536107

  10. 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.

  11. Features of water chemical composition of oligotrophic and eutrophic bogs in the South of the Tomsk region

    NASA Astrophysics Data System (ADS)

    Naymushina, O.

    2016-03-01

    On the basis of the actual material the analysis of chemical composition of bog waters in the territory of the South of the Tomsk region is carried out. The data on average concentration of macro and trace components, organic matter, pH of bog waters are obtained. Significant distinctions in a chemical composition of surface water for different types of bogs are revealed. The composition and macrostructure of humic acids by the example of eutrophic bogs is studied.

  12. 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

  13. EVALUATING CUMULATIVE EFFECTS OF DISTURBANCE ON THE HYDROLOGIC FUNCTION OF BOGS, FENS, AND MIRES

    EPA Science Inventory

    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. or example, few data are available on the role of bogs and fens with ...

  14. 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.

  15. 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).

  16. Why Do People Engage in Corruption? The Case of Estonia

    ERIC Educational Resources Information Center

    Tavits, Margit

    2010-01-01

    This study uses survey data for 2004 on the general public (N = 788) and public officials (N = 791) in the young post-communist democracy of Estonia to examine individual-level determinants of corruption. The results indicate that both public officials and citizens are more likely to engage in corruption when they do not define corruption as…

  17. Adoption of National Curricula by Vocational Teachers in Estonia

    ERIC Educational Resources Information Center

    Rekkor, Sirje; Ümarik, Meril; Loogma, Krista

    2013-01-01

    This article aims to study the adoption of national curricula by vocational teachers. In the paper, we review the process of vocational education and training curriculum reform in Estonia over the last 20 years, and, in particular, the introduction of national curricula. As teachers should be considered the key agents of curricular change, we look…

  18. Reviews of National Policies for Education: Estonia. Education and Skills.

    ERIC Educational Resources Information Center

    Organisation for Economic Cooperation and Development, Paris (France).

    Reform of education, training, and human resource development is an integral part of the transition to a democratic society and market economy. Estonia has made progress in all these areas since reform began in 1990. The challenge for the Ministry of Education has been to promote and support changes that meet the needs of the new economy and…

  19. 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...

  20. 76 FR 77814 - Cameron LNG, LLC; Notice of Intent To Prepare an Environmental Assessment for the Proposed BOG...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-14

    ... for the Proposed BOG Liquefaction Project, and Request for Comments on Environmental Issues The staff... assessment (EA) that will discuss the environmental impacts of the BOG Liquefaction Project involving... construct and operate facilities necessary to liquefy boil-off gas (BOG) at its existing liquefied...

  1. 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... Environmental Assessment (EA) that will discuss the environmental impacts of the Elba BOG Compressor Project... (BOG) compression facilities at its liquefied natural gas (LNG) marine terminal on Elba Island...

  2. Fate of silicate minerals in a peat bog

    NASA Astrophysics Data System (ADS)

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

    1991-04-01

    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.

  3. 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. PMID:25973580

  4. 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. PMID:22664536

  5. 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

    Raised bogs in Ireland have long been exploited for local fuel utilisation. The drainage associated with such activities alters the hydrological regime of the bog as consolidation of the peat substrate results in significant water loss and subsidence of the bog. Undisturbed raised bog environments are typically characterised by distinct ecological systems, or ecotopes, which are controlled by the relationship between surface slopes, flow path lengths and drainage conditions. Shrinkage of the main peat profile, or catotelm, invariably alters these conditions, changes of which significantly damage ecotopes of conservational value. Clara Bog, Ireland, is one of western Europe's largest remaining raised bogs and on which much hydroecological research has been conducted since the early 1990's. Though a relatively intact raised bog, it has been extensively damaged in the past with the construction of a road through the centre of the bog known to have resulted in subsidence of 9-10m. However, the western tract of Clara Bog, Clara Bog West, has also subsided significantly since the early 1990's due to on-going peat cutting activities on the bogs margins. Current research now indicates that the bog is not an isolated hydrological entity, as generally perceived of bogs, but rather that Clara Bog West is intrinsically linked to the regional groundwater table, which appears to provide a significant ‘support' function to the bog. Hydrogeological monitoring and analysis has shown that water losses are not simply a result of lateral seepage of water through the peat profile at the bogs margins. Measurements of flow rates and electrical conductivity in drains bordering the bog indicate that little water is discharging laterally through the peat profile. However, piezometric head levels in mineral subsoil underlying the bog and close to the margins of the bog have decreased by 0.3 to 0.5m and 0.4 to 1.0m respectively since the early 1990s and it is believed that this is a result

  6. 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. PMID:26220310

  7. 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.

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

    NASA Astrophysics Data System (ADS)

    Heusser, Calvin J.

    1982-01-01

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

  9. Dating Kaali Crater (Estonia) based on charcoal emplaced within proximal ejecta blanket

    NASA Astrophysics Data System (ADS)

    Losiak, Anna; Wild, Eva Maria; Huber, Matthew S.; Wisniowski, Tomasz; Paavel, Kristiina; Jõeleht, Argo; Välja, Rudolf; Plado, Jüri; Kriiska, Aivar; Wilk, Jakob; Zanetti, Michael; Geppert, Wolf D.; Kulkov, Alexander; Steier, Peter; Pirkovic, Irena

    2015-04-01

    The Kaali impact field consists of nine identified craters located on the Saaremaa Island in Estonia. The largest crater is 110 m in diameter (centered around 58°22'21.94"N, 22°40'09.91" E). It was formed by impact of an IAB iron meteoroid into Silurian dolomite target rocks covered by up to a few meters of glacial till (Veski et al. 2007). The age of the Kaali impact structure is still a matter of debate, and the estimates provided by different authors vary considerably between ~6400 BC (Raukas et al. 1995, Moora et al. 2012) and ~400 BC (Rasmussen et al. 2000, Veski et al. 2001). These ages were derived by 14C dating of marker horizons, characterized by a slightly elevated iridium content within the nearby Piila bog yielding a calibrated age of 800-400 BC (Rasmussen et al. 2000, Veski et al. 2001) and occurrences of glassy siliceous material in the Piila bog (~6400 BC: Raukas et al. 1995) or iron microspherules in an organic-rich layer of the Reo gravel pit (6400 BC: Moora et al. 2012). However, the source of the foreign material within those layers was never unequivocally connected with the Kaali crater. 14C dating of material from post-impact organic sediments within Kaali impact craters yielded ages between 1800-1500 BC (Saarse et al. 1991, Veski et al. 2004) and 1450-400 BC (Aaloe et al. 1963). These dates underestimate the age of impact as organic sediments within the crater started to form at unknown period after the impact. On the other hand, Veski et al. (2004) suggested a reservoir effect that might have caused artificially "aging" of the organic matter because the crater was emplaced within Silurian dolomite which is rich in old carbon. The aim of this study is to determine the age of the Kaali crater by 14C dating of organic material covered by the continuous layer of proximal ejecta. This research was conducted in conjunction with a new structural investigation of Kaali Main (Zanetti et al. 2015). Ten samples collected from different locations

  10. Phenolic compounds in five Epilobium species collected from Estonia.

    PubMed

    Remmel, Indrek; Vares, Lauri; Toom, Lauri; Matto, Vallo; Raal, Ain

    2012-10-01

    Epilobium species have been traditionally used as medicinal plants to treat benign prostate hyperplasia. The present study investigated the content of polyphenols, tannins, and flavonoids in Epilobium parviflorum Schreb., E. hirsutum L., E. adenocaulon Hausskn., E. montanum L., and E. palustre L. growing in Estonia. The total contents of polyphenols, tannins, and flavonoids were studied using UV spectroscopy with subsequent HPLC quantification of gallic acid, ellagic acid, and quercetin as marker compounds. All roots, stems, leaves, and flowers of the plants investigated contained comparable amounts of polyphenols, tannins, and flavonoids. There was a clear positive correlation between the contents of tannins and flavonoids in various plant parts. The content of these biologically active compounds suggests the use of E. parviflorum, E. hirsutum, E. adenocaulon, E. montanum, and E. palustre collected from Estonia as herbs both individually or as a blend. PMID:23156999

  11. The verification of GIA in Estonia using GNSS data

    NASA Astrophysics Data System (ADS)

    Kollo, Karin; Oja, Tõnis

    2014-05-01

    Estonia is situated at the South-East corner of the Fennoscandian post-glacial rebound (PGR) area, thus the impact of ongoing Glacial Isostatic Adjustment could be noticed on accurate geodetic measurements; e.g. in Estonia the uplift rates up to 4 mm/yr have been observed so far. In this contribution we use horizontal and vertical uplift rates derived from (1) the time series of several Estonian GNSS permanent reference stations (CORS), and (2) nation-wide GPS campaigns held in 1997 and 2008. Different methods and software were used to process and analyse GNSS data and time series. Slight discrepancies between the results helped to evaluate the effects of different approaches in data processing. To model the surface displacements and other geodetic quantities in response to the melting of ice sheets the open source software SELEN (Spada and Stocchi, 2007) with several ice models was used. The observed displacements of geodetic points as well as velocity estimates of CORS were compared with the predictions of latest PGR empirical models (e.g. NKG2005LU) and with the results from GIA modelling. In most cases good fit between the observations and models was found within study area. The higher discrepancies appeared in the East and South-East Estonia. Besides noise in aforementioned measurements the reason could be that almost no observed data from study area have been used in compilation of widespread (common, well-known) ice and GIA models. Keywords: GNSS measurements, postglacial rebound, glacial isostatic adjustment, Estonia. References Spada, G., Stocchi, P. (2007). SELEN: A Fortran 90 program for solving the "sea-level equation". Computers & Geosciences, 33:538-562, 2007.

  12. 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

  13. 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

  14. On Connections Between Weather Types and the Arrival of Migratory Birds in Estonia

    NASA Astrophysics Data System (ADS)

    Sepp, M.; Päädam, K.; Palm, V.; Leito, A.

    2010-09-01

    fact that Tartu and Kuressaare are located on the same latitude (58°N) and their distance is relatively small (ca 250 km), there are clear differences in the arrival dates of birds. Species that arrive in Estonia before mid-April (early arrivals) reach Kuresaare up to a week earlier compared to Tartu (the earlier the date of arrival, the greater the difference). Later arrivals, however, reach Tartu up to a week earlier than the Estonian Western islands. Analysis of weather types revealed a clear difference in "preferences" of the late and early arrivals. The early arrivals prefer more cyclonic conditions, when the main air flow into Estonia is from the Western or South-Western directions. Late migrants prefer anti-cyclonic conditions when sunny and warm weather conditions prevail with wind from the Southern direction. There also occurred a clear distinction between late and early migrants in the case of "avoidable" weather types. Early migrants clearly avoid the anti-cyclonic weather types and the types in whose case the general direction of air masses is from the North. In the case of late migrants, a clear weather type preference did not occur. But in general they avoid cyclonic conditions with winds from the Western or Northern directions.

  15. 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. PMID:27110977

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

    PubMed

    Holzinger, Werner E; Schlosser, Lydia

    2013-01-01

    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

  17. The water balance as an approach to assessing groundwater dependency in raised bog wetlands

    NASA Astrophysics Data System (ADS)

    Regan, Shane

    2014-05-01

    The management of raised bogs, as active peat-forming ecosystems, requires an understanding of the relationships between regional hydrology and wetland ecohydrological processes. Marginal drainage, < 20 years, of Clara Bog, Ireland, has resulted in dramatic morphological changes. Differential peat consolidation has fragmented what was one topographic catchment area into four distinct catchment areas. Runoff has reduced by c. 40% from the original main catchment area and there has been a c. 25% decrease of suitably saturated areas supporting the growth of sphagnum moss species. In undisturbed bog systems the recharge rate of water seeping through the bog body to the regional groundwater table is in the order of 40 mm/ year. The downward seepage rate in Clara is > 100 mm/ year. A reduction in pore water pressure, due to drainage of the regional groundwater table, has disturbed the structure of the peat substratum and induced water loss from peat storage, resulting in the ecohydrological modification of the bog surface. Numerical modelling of a simulated raised groundwater table reduces the leakage rate to between 30 and 50 mm/ year. The significance is that the hydraulic gradient of the regional groundwater table is an important environmental supporting condition in raised bog ecosystems, implying indirect groundwater dependence.

  18. The Affective Dimension of Religion and Personal Happiness among Students in Estonia

    ERIC Educational Resources Information Center

    Francis, Leslie J.; Elken, Ahto; Robbins, Mandy

    2012-01-01

    A sample of 150 students in Estonia (119 from a secular university and 31 from a Lutheran theological institute) completed the Oxford Happiness Measure and the Francis Scale of Attitude toward Christianity. The data show no significant correlation between these two variables; thus the findings challenge the generalizability to Estonia of the…

  19. 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

  20. Can continental bogs withstand the pressures from climate change?

    NASA Astrophysics Data System (ADS)

    Roulet, Nigel; Humphreys, Elyn; Wu, Jianghua; Frolking, Steve; Talbot, Julie; Lafleur, Peter; Moore, Tim

    2016-04-01

    Not all peatlands are alike. Theoretical and process based models suggest that ombrogenic, oligotrophic peatlands can withstand the pressures due to climate change because of the feedbacks among ecosystem production, decomposition and water storage. Although there have been many inductive explanations inferring from paleo-records, there is a lack of deductive empirical tests of the models predictions of these systems' stability and there are few records of the changes in the net ecosystem carbon balance (NECB) of peatlands that are long enough to examine the dynamics of the NECB in relation to climate variability. Continuous measurements of all the components of the NECB and the associated general climatic and environmental conditions have been made at the Mer Bleue (MB) peatland, a large, 28 km2, 5 m deep, raised ombro-oligotrophic, shrub and Sphagnum covered bog, near Ottawa, Canada from May 1, 1998 until the present. The sixteen-year daily CO2, CH4, and DOC flux and NECB covers a wide range of variability in peatland water storage from very dry to very wet growing seasons. We used the MB data to test the extent of MB peatland's stability and the strength of the underlying key feedback between the NECB and changes in water storage projected by the models. In 2007 we published a six-year (1999-2004) net ecosystem carbon balance (NECB) for MB of ~22 ± 40 g C m-2 yr-1, but we have since recalculated the 1998-2004 NECB to be 32 ± 40 g C m-2 yr-1 based on a reanalyzed average NEP of 51 ± 41 g C m-2 yr-1. Over the same period the net loss of C via the CH4 and DOC fluxes were -4 ± 1 and -15 ± 3 g C m-2 yr-1. The 1998-2004 six-year MB average NECB is similar to the long-term C accumulation rate, estimated from MB peat cores, for the last 3,000 years. The post 2004 MB NEP has increased to an average of ~96 ± 32 g C m-2 yr-1 largely to there being generally wetter growing seasons. The losses of C via DOC (18 ± 1 g C m-2 yr-1) and CH4 (7 ± 4 g C m-2 yr-1) while

  1. 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

  2. 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

  3. 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

  4. 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

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

    NASA Astrophysics Data System (ADS)

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

    2016-05-01

    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.

  6. 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. PMID:27034028

  7. 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)

  8. 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.

  9. 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.

  10. 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. PMID:25310886

  11. Thyroid nodularity and cancer among Chernobyl cleanup workers from Estonia

    SciTech Connect

    Inskip, P.D.; Boice, J.D. Jr.; Tekkel, M.

    1997-02-01

    Thyroid examinations, including palpation, ultrasound and, selectively, fine-needle aspiration biopsy, were conducted on nearly 2,000 Chernobyl cleanup workers from Estonia to evaluate the occurrence of thyroid cancer and nodular thyroid disease among men with protracted exposure to ionizing radiation. The examinations were conducted in four cities in Estonia during March-April 1995, 9 years after the reactor accident. The study population was selected from a predefined cohort of 4,833 cleanup workers from Estonia under surveillance for cancer incidence. These men had been sent to Chernobyl between 1986 and 1991 to entomb the damaged reactor, remove radioactive debris and perform related cleanup activities. A total of 2,997 men were invited for thyroid screening and 1,984 (66%) were examined. Estimates of radiation dose from external sources were obtained from military or other institutional records, and details about service dates and types of work performed while at Chernobyl were obtained from a self-administered questionnaire. Blood samples were collected for assay of chromosomal translocations in circulating lymphocytes and loss of expression of the glycophorin A (GPA) gene in erythrocytes. The primary outcome measure was the presence or absence of thyroid nodules as determined by the ultrasound examination. Of the screened workers, 1,247 (63%) were sent to Chernobyl in 1986, including 603 (30%) sent in April or May, soon after the accident. Workers served at Chernobyl for an average of 3 months. The average age was 32 years at the time of arrival at Chernobyl and 40 years at the time of thyroid examination. The mean documented radiation dose from external sources was 10.8 cGy. Biological indicators of exposure showed low correlations with documented dose, but did not indicate that the mean dose for the population was higher than the average documented dose. 47 refs., 1 fig., 9 tabs.

  12. Seasonality of alcohol-related phenomena in Estonia

    NASA Astrophysics Data System (ADS)

    Silm, Siiri; Ahas, Rein

    2005-03-01

    We studied alcohol consumption and its consequences as a seasonal phenomenon in Estonia and analysed the social and environmental factors that may cause its seasonal rhythm. There are two important questions when researching the seasonality of human activities: (1) whether it is caused by natural or social factors, and (2) whether the impact of the factors is direct or indirect. Often the seasonality of social phenomena is caused by social factors, but the triggering mechanisms are related to environmental factors like temperature, precipitation, and radiation via the circannual calendar. The indicators of alcohol consumption in the current paper are grouped as: (1) pre-consumption phenomena, i.e. production, tax and excise, sales (beer, wine and vodka are analysed separately), and (2) post-consumption phenomena, i.e. alcohol-related crime and traffic accidents and the number of people detained in lockups and admitted to alcohol treatment clinics. In addition, seasonal variability in the amount of alcohol advertising has been studied, and a survey has been carried out among 87 students of Tartu University. The analysis shows that different phenomena related to alcohol have a clear seasonal rhythm in Estonia. The peak period of phenomena related to beer is in the summer, from June to August and the low point is during the first months of the year. Beer consumption correlates well with air temperature. The consumption of vodka increases sharply at the end of the year and in June; the production of vodka does not have a significant correlation with negative temperatures. The consumption of wine increases during summer and in December. The consequences of alcohol consumption, expressed as the rate of traffic accidents or the frequency of medical treatment, also show seasonal variability. Seasonal variability of alcohol consumption in Estonia is influenced by natural factors (temperature, humidity, etc.) and by social factors (celebrations, vacations, etc.). However

  13. Chemical and isotopic properties of kukersites from Iowa and Estonia

    USGS Publications Warehouse

    Mastalerz, Maria; Schimmelmann, A.; Hower, J.C.; Lis, G.; Hatch, J.; Jacobson, S.R.

    2003-01-01

    Kukersite samples from Estonia and Iowa were analyzed for elemental composition, functional group distribution, and carbon and hydrogen stable isotope ratios. The elemental and hydrogen isotope values, together with other analytical data, suggest a higher thermal maturity for the Iowa kukersite. The wide carbon isotopic range of 9.3??? among kukersites, with unusually negative ??13C values reaching -33.2???, indicates isotopically variable carbon sources for production of biomass, and thus major paleoceanographic differences between the environments supporting biosynthesis. ?? 2003 Elsevier Ltd. All rights reserved.

  14. 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.

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

    NASA Astrophysics Data System (ADS)

    Förster, Christoph; Drösler, Matthias

    2014-05-01

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

  16. 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

  17. 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.

  18. 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. PMID:25113243

  19. 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)

  20. The social costs of alcohol misuse in Estonia.

    PubMed

    Saar, Indrek

    2009-01-01

    The aim of this study was to estimate the social costs of alcohol misuse in Estonia in 2006. Using a prevalence-based cost-of-illness approach, both direct and indirect costs were considered, including tangible costs associated with health care, criminal justice, rescue services, damage to property, premature mortality, incarceration, incapability of working due to illnesses, and lower labor productivity. The results show that alcohol misuse cost Estonia more than EUR 200 million in 2006. The costs involved are estimated to represent 1.6% of the gross domestic product (GDP), which is relatively high in comparison with many other countries. In addition, the state receives less receipts from the alcohol excise tax than the costs that it incurs as a consequence of alcohol misuse, which points to the existence of economic inefficiency with respect to the alcohol market. The results of this study suggest that there is definitely a need for further cost-benefit analysis to reach a conclusion regarding the possible utility of government intervention. PMID:19052463

  1. Draft Genome Sequences of Three Chromobacterium subtsugae Isolates from Wild and Cultivated Cranberry Bogs in Southeastern Massachusetts

    PubMed Central

    Vöing, Kristin; Harrison, Alisha

    2015-01-01

    Chromobacterium subtsugae was isolated from cranberry bogs in Massachusetts. While it is unknown what environmental role these bacteria play in bog soils, they hold potential as biological control agents against the larvae of insect pests. Potential virulence genes were identified, including the violacein synthesis pathway, siderophores, and several chitinases. PMID:26358592

  2. Changing sources of respiration between a black spruce forest and thermokarst bog

    NASA Astrophysics Data System (ADS)

    Waldrop, M. P.; McFarland, J.; Czimczik, C. I.; Euskirchen, E. S.; Amendolara, T.; Scott, G. J.; Turetsky, M. R.; Harden, J. W.; McGuire, A. D.

    2011-12-01

    Permafrost thaw in lowland black spruce forests (Picea mariana) which develop into thermokarst bogs can alter ecosystem carbon balance through positive or negative feedbacks to climate warming. In this context, the responses of plant and soil microbial communities to permafrost thaw, and their roles in altered carbon balance, need to be understood. In addition, gross changes in microbial community composition, such as fungal:bacterial ratios and their temperature response functions, are poorly characterized in permafrost thaw experiments. In this study, we compared carbon fluxes between a lowland black spruce forest with intact permafrost and an adjacent thermokarst bog that developed 20-30 years ago located near the Bonanza Creek Experimental Forest in Alaska. We quantified net ecosystem exchange (NEE), ecosystem respiration (ER), and gross primary productivity (GPP) using flux autochambers, and partitioned sources of ecosystem respiration into autotrophic vs. heterotrophic sources using radiocarbon analysis of ecosystem and microbial respiration, and atmospheric CO2. We further partitioned microbial respiration into fungal vs. bacterial sources using substrate inhibition techniques. Preliminary results indicate that in mid summer of 2011 the thermokarst bog was a source of CO2 to the atmosphere. NEE data indicated that the black spruce understory was a source of CO2. However, because flux tower data showed that the black spruce ecosystem was actually a net sink, GPP by the black spruce trees must have been large. In the black spruce forest ER was dominated by plant respiration in the spring and by microbial respiration in the fall whereas in the thermokarst bog CO2 was derived from deeper soil C sources. Although microbial respiration was roughly balanced between fungi and bacteria in the black spruce forest, respiration was dominantly bacterial in the thermokarst bog. Our initial results show that thermokarst bogs are source of C to the atmosphere during summer

  3. 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.

  4. 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. PMID:26335913

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

    NASA Astrophysics Data System (ADS)

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

    2012-04-01

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

  6. Improving the terrestial gravity dataset in South-Estonia

    NASA Astrophysics Data System (ADS)

    Oja, T.; Gruno, A.; Bloom, A.; Mäekivi, E.; Ellmann, A.; All, T.; Jürgenson, H.; Michelson, M.

    2009-04-01

    The only available gravity dataset covering the whole of Estonia has been observed from 1949 to 1958. This historic dataset has been used as a main input source for many applications including the geoid determination, the realization of the height system, the geological mapping. However, some recent studies have been indicated remarkable systematic biases in the dataset. For instance, a comparison of modern gravity control points with the historic data revealed unreasonable discrepancies in a large region in South-Estonia. However, the distribution of the gravity control was scarce, which did not allow to fully assess the quality of the historic data in the study area. In 2008 a pilot project was called out as a cooperation between Estonian Land Board, Geological Survey of Estonia, Tallinn University of Technology and Estonian University of Life Sciences to densify the detected problematic area (about 2000 km2) with new and reliable gravity data. Field work was carried out in October and November 2008, whereas GPS RTK and relative Scintrex gravimeter CG5 were used for precise positioning and gravity determinations, respectively. Altogether more than 140 new points were determined along the roads. Despite bad weather conditions and unstable observation base of the gravimeter (mostly on the bank of the road), uncertainty better than ±0.1 mGal (1 mGal = 10-5 m/s2) was estimated from the adjustment of gravimeter's readings. The separate gravity dataset of the Estonian Geological Survey were also incorporated into the gravity database of the project for further analysis. Those data were collected within several geological mapping projects in 1981-2007 and contain the data with uncertainty better than ±0.25 mGal. After the collection of new gravity data, a Kriging with proper variogram modeling was applied to form the Bouguer anomaly grids of the historic and the new datasets. The comparison of the resulting grids revealed biases up to -4 mGal at certain regions

  7. Support Structures for Innovation and Research-based Entrepreneurship in Estonia.

    ERIC Educational Resources Information Center

    Tamkivi, Raivo

    1999-01-01

    In a transition economy, Estonia is taking a systematic approach to research and development and technology transfer through two programs: a science park for incubation of small enterprises and a technical university innovation center. (SK)

  8. 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

  9. Recent changes in breast cancer incidence and mortality in Estonia: Transition to the west.

    PubMed

    Baburin, Aleksei; Aareleid, Tiiu; Rahu, Mati; Reedik, Lauri; Innos, Kaire

    2016-06-01

    Background The aim of this study was to examine breast cancer (BC) incidence and mortality trends in Estonia during recent decades and to compare the pattern of these trends with other selected European countries and regions. We attempt to explain the findings in relation to changes in Estonian society and healthcare system. Methods BC incidence (1985-2012) and mortality (1985-2013) data for Estonia were obtained from the Estonian Cancer Registry and Statistics Estonia. Data for selected European countries were obtained from the EUREG database. Joinpoint regression was used to analyze age-standardized rates in Estonia by age. For international comparison of incidence and mortality rates, we used scatterplot with 95% confidence ellipses and the mortality to incidence ratio. Results The overall BC incidence continues to increase in Estonia, while mortality has been in decline since 2000. Both incidence and mortality trends varied considerably across age groups. Among women aged 60 years and older, BC incidence increased at a rate of nearly 3% per year. Significant decrease in mortality was seen only among women aged 50-59 years. Comparison of scatterplots between countries and regions revealed two clusters in Europe separated along the incidence axis. The correlation between incidence and mortality in Estonia changed its direction in the mid-1990s. Conclusion In recent years, the dynamics of BC burden in Estonia has transitioned towards the high incidence-low mortality type model, which is characteristic to Western, Northern and Southern Europe. Although overall BC incidence is much lower in Estonia than in more affluent European countries, mortality from BC is still relatively high, particularly among elderly women. PMID:27222251

  10. An Energy Overview of the Republic of Estonia

    SciTech Connect

    anon.

    2003-10-20

    The DOE Office of Fossil Energy is maintaining a web site that is meant to provide useful business- and energy-related information about countries and regions of the world for exporters, project developers, and researchers. The site consists of more than 130 country pages (organized into seven different world regions), with each country page having its own set of links to information sources about that country. There are also more than 30 Country Energy Overviews at the web site -- each of these is a comprehensive review of a specific country's entire energy situation, including sections on Energy Policy, Oil, Natural Gas, Coal, Hydroelectric/Renewables, Nuclear Power, Energy Transmission Infrastructure, Electricity, Electric Industry Overview, Environmental Activities, Privatization, Trade, and Economic Situation. The specific country highlighted in this Country Energy Overview is Estonia. The site is designed to be dynamic. Updates to the overviews will be made as need and resources permit.

  11. The sociodemographic patterning of drinking and binge drinking in Estonia, Latvia, Lithuania and Finland, 1994–2002

    PubMed Central

    Helasoja, Ville; Lahelma, Eero; Prättälä, Ritva; Petkeviciene, Janina; Pudule, Iveta; Tekkel, Mare

    2007-01-01

    Background Despite the relatively low recorded alcohol consumption level, the Baltic countries (Estonia, Latvia and Lithuania) and neighbouring Finland suffer from similar harmful consequences related to the use of alcoholic beverages, including socio-economic inequalities in alcohol related mortality. Comparative evidence is needed to understand harmful drinking patterns and to implement preventive alcohol policies also in the Baltic countries. This study compared heavy and binge drinking by sex, age, education, urbanisation and marital status in the Baltic countries and Finland. Methods The data were nationally representative postal surveys conducted in Estonia (n = 6271), Latvia (n = 6106), Lithuania (n = 7966) and Finland (n = 15764) during 1994–2002. The criterion for heavy drinking was at least 15 portions weekly among men, and at least five among women, and for binge drinking at least six portions per one occasion. Results Heavy drinking was more common among younger participants in all countries, and in Latvia among the less-educated. Among Finnish men, and among women from all countries except Latvia, the better-educated were more often heavy drinkers. In Latvia and Finland, urban men, and in all countries, urban women, were more often heavy drinkers. Heavy drinking was more common among non-married Lithuanian and Finnish men, and Finnish women. Binge drinking was more common among less-educated Estonian and Latvian men, and among younger and less-educated women in all countries. Conclusion Our results support the continued power of traditional drinking habits in the North Eastern part of Europe. In the future the target groups for prevention of excessive drinking should also include young and less-educated women in all four countries studied. PMID:17854484

  12. 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.

  13. Peat bog Records of Atmospheric Dust fluxes - Holocene palaeoenvironmental and paleoclimatic implications for South America

    NASA Astrophysics Data System (ADS)

    De Vleeschouwer, François; Vanneste, Heleen; Bertrand, Sébastien; Coronata, Andrea; Gaiero, Diego; Le Roux, Gael

    2013-04-01

    Little attention has been given to pre-anthropogenic signals recorded in peat bogs, especially in the Southern Hemisphere. Yet they are important to 1/ better understand the different particle sources during the Holocene and 2/ to tackle the linkage between atmospheric dust loads and climate change and 3/ to better understand the impact of dust on Holocene palaeoclimate and palaeoenvironments in a critical area for ocean productivity. In the PARAD project, we will explore the use of a broad range of trace elements and radiogenic isotopes (Pb, Nd, Hf) as dust proxies. Coupling these findings with biological proxies (plant macrofossils, pollen) and detailed age-depth modelling, we expect not only to identify and interpret new links between atmospheric dust chemistry and climate change. In this contribution, we will present the preliminary results on two peat records of natural atmospheric dust using the elemental and isotopic signature in Tierra del Fuego. Preliminary results on two peat sections covering the Holocene (Karukinka Bog, Chile, 8kyrs and Harberton bog, Argentina, 14kyrs) will be discussed. This encompasses density, ash content, elemental and isotopic geochemistry, macrofossil determination and radiocarbon dating. More specifically, Karukinka bog display several mineral peaks, which possible origin (soil particles, volcanism, cosmogenic dusts, marine aerosols…) will be discussed here as well as in Vanneste et al. (this conference, session Aeolian dust: Initiator, Player, and Recorder of Environmental Change).

  14. 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.

  15. 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…

  16. A probe for sampling interstitial waters of stream sediments and bog soils

    USGS Publications Warehouse

    Nowlan, G.A.; Carollo, C.

    1974-01-01

    A probe for sampling interstitial waters of stream sediments and bog soils is described. Samples can be obtained within a stratigraphic interval of 2-3 cm, to a depth of 60-80 cm, and with little or no contamination of the samples by sediment or air. ?? 1974.

  17. 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

  18. Spectral reflectance patterns and temporal dynamics of common understory types in hemi-boreal forests in Järvselja, Estonia

    NASA Astrophysics Data System (ADS)

    Nikopensius, Maris; Raabe, Kairi; Pisek, Jan

    2014-05-01

    The knowledge about spectral properties and seasonal dynamics of understory layers in boreal forests currently holds several gaps. This introduces severe uncertainties while modelling the carbon balance of this ecosystem, which is expected to be prone to major shifts with climate change in the future. In this work the seasonal reflectance dynamics in European hemi-boreal forests are studied. The data for this study was collected at Järvselja Training and Experimental Forestry District (Estonia, 27.26°E 58.30°N). Measurements were taken in three different stands. The silver birch (Betula Pendula Roth) stand grows on typical brown gley-soil and its understory vegetation is dominated by a mixture of several grass species. The Scots pine (Pinus sylvestris) stand grows on a bog with understory vegetation composed of sparse labrador tea, cotton grass, and a continuous Sphagnum moss layer. The third stand, Norway spruce (Picea abies), grows on a Gleyi Ferric Podzol site with understory vegetation either partially missing or consisting of mosses such as Hylocomium splendens or Pleurozium schreberi [1]. The sampling design was similar to the study by Rautiainen et al. [3] in northern European boreal forests. At each study site, a 100 m long permanent transect was marked with flags. In addition, four intensive study plots (1 m × 1 m) were marked next to the transects at 20 m intervals. The field campaign lasted from May to September 2013. For each site the fractional cover of understory and understory spectra were estimated ten times i.e. every 2 to 3 weeks. Results from Järvselja forest were compared with the seasonal profiles from boreal forests in Hyytiälä, Finland [2]. References [1] A. Kuusk, M. Lang, J. Kuusk, T. Lükk, T. Nilson, M. Mõttus, M. Rautiainen, and A. Eenmäe, "Database of optical and structural data for validation of radiative transfer models", Technical Report, September 2009 [2] M. Rautiainen, M. Mõttus, J. Heiskanen, A. Akujärvi, T. Majasalmi

  19. 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.

  20. 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.

  1. Aeolian Coastal Landscapes in changes (a study from Tahkuna, Estonia)

    NASA Astrophysics Data System (ADS)

    Anderson, A.

    2012-04-01

    The openness of the coast to the winds and storm waves has an important part in changing aeolian coastal landscapes as well as anthropogenic factor. The aeolian coastal landscapes are probably the most dynamic areas. Occurrence of aeolian coastal landscapes in Estonia is limited. They consist of sandy beaches, sandy beach ridges and dunes. The coastal ecosystems are strongly affected by their topography, based on the character of deposits and moisture conditions. The majority of their ecosystems are quite close to the specific natural habitat. These ecosystems are represented in the list of the European Union Habitats (Natura 2000). In recent decades human influence has changed the landscape over time in different activities (recreation, trampling, off-road driving) and their intensities, which has led to destruction or degradation of various habitats. Previously coastal landscapes were used for forestry and pasture. Nowadays one of the most serious threats to open landscape is afforestation. This study examines the relationships between landscape components during last decades. Trying to find out how much aeolian coastal landscapes are influenced by natural processes or human activities. The results are based on cartographic analysis, fieldwork data. The method of landscape complex profile was used. The profiles show a cross-sections of landforms and interrelationships between landscape components, most frequently describing the relations between soils and vegetation. In each sample point the mechanical composition of sediments, vegetation cover and soil is determined. Results show that changes in landscapes are induced by their own development as well as changes in environmental factors and human activities. Larger changes are due to increase of coastal processes activity. These processes can be observed in sandy beaches, which are easily transformed by waves. Higher sea levels during storm surges are reaching older beach formation, causing erosion and creating

  2. 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. PMID:26010098

  3. Antibiotic prescription preferences in paediatric outpatient setting in Estonia and Sweden.

    PubMed

    Lass, Jana; Odlind, Viveca; Irs, Alar; Lutsar, Irja

    2013-12-01

    Aims of the study were to compare the paediatric outpatient antibiotic use in two countries with low overall antibiotic consumption and antibacterial resistance levels - Sweden and Estonia - and to describe the adherence to Estonian treatment guideline. All prescriptions for systemic antibiotics for children less than 18 years during 2007 from the Swedish Prescribed Drug Register and Estonian Health Insurance Fund database were identified to conduct a descriptive drug utilisation study. The total paediatric antibiotic use was 616 and 353 per 1000 in Estonia and Sweden, respectively. The greatest between country differences occurred in the age group 2 to 6 years -Estonian children received 1184 and Swedish children 528 prescriptions per 1000. Extended spectrum penicillin amoxicillin (189 per 1000) or its combination with beta-lactamase inhibitor (81 per 1000) and a newer macrolide clarithromycin (127 per 1000) were prescribed most often in Estonia whereas narrow spectrum penicillin phenoxymethylpenicillin (169 per 1000) and older generation macrolide erythromycin (21 per 1000) predominated in Sweden. For acute bronchitis, 17 different antibiotics (most commonly clarithromycin) were prescribed in Estonia despite the guideline recommendation not to use antibiotics. The higher rate of antibiotic use especially of extended spectrum antibiotics in Estonia compared to Sweden emphasizes the need for national activities to promote appropriate use of antibiotics while treating children, even when the overall antibiotic consumption is low. PMID:23667800

  4. Mutual Trust between Kindergarten Teachers and Mothers and Its Associations with Family Characteristics in Estonia and Finland

    ERIC Educational Resources Information Center

    Kikas, Eve; Poikonen, Pirjo-Liisa; Kontoniemi, Marita; Lyyra, Anna-Liisa; Lerkkanen, Marja-Kristiina; Niilo, Airi

    2011-01-01

    Mutual trust between mothers and kindergarten teachers along with its relation to mother's educational level and child's gender was studied in two neighboring countries--Estonia and Finland. From Estonia 543 ratings of mothers and 232 ratings of teachers were collected, and, from Finland, 712 ratings of mothers and 712 ratings of teachers. Trust…

  5. Moving the Field Forward: A Micro-Meso-Macro Model for Critical Language Planning. The Case of Estonia

    ERIC Educational Resources Information Center

    Skerrett, Delaney Michael

    2016-01-01

    This study investigates "de facto" language policy in Estonia. It investigates how language choices at the micro (or individual) level are negotiated within the macro (or social and historical) context: how official language policy and other features of the discursive environment surrounding language and its use in Estonia translate into…

  6. Women in Physics in Estonia: Many Duties, One Life

    NASA Astrophysics Data System (ADS)

    Kaasik, Helle

    2009-04-01

    In Estonia, women and men have equal legal rights. Women are expected to earn their living like men—and unlike men, to be the main (often the only) caregiver for the children. In the family women do most of the unpaid work, spending twice the amount of time on household duties as men. Laws about public preschool child care and child support obligations for noncustodial parents exist, but these laws are not always realized in practice. A generous policy of benefits for children under 1.5 years provides some relief for mothers. It is a challenge to balance a woman's traditional load of unpaid duties with the high demands of a science career. As in many other countries, with every step up the academic ladder the underrepresentation of women in science becomes more evident. Physics and engineering are perceived as male areas and women active in these areas are often treated as exceptions. Most obstacles met by women in science are difficult to recognize and neutralize because they are deeply informal. Activities for "gender and science" that exceed the limits of sociological study have no long tradition here and are yet finding their place in Estonian society.

  7. Effectiveness of Environmental Impact Assessment system in Estonia

    SciTech Connect

    Heinma, Kaupo; Poder, Tonis

    2010-07-15

    To be effective, an Environmental Impact Assessment (EIA) system, first, has to minimize the probability that projects with significant environmental effects are implemented without EIA, and second, minimize the number of EIAs, which do not provide decision makers with essential information, so that the decision is improved as a result of EIA. The objective of this study was to find out how frequently in Estonia the projects implemented without EIA have caused significant environmental effects, and to measure the relative frequency of EIAs that have no influence on decision. An extensive survey with e-mail distributed questionnaires was carried out to reveal information from governmental agencies, local self-governments, and developers. There was no evidence that projects authorized without EIA have had environmental impacts, which could have been mitigated as a result of EIA. In contrast, about half of EIAs did not alter the decision of relevant authorities. This proportion was valid to both mandatory EIAs and those initiated on judgement basis. In our view, the proportion of no-influence EIAs was excessive and indicated the need to reconsider the provisions applying to the projects with a mandatory EIA requirement as well as judgements practice.

  8. Fluoride occurrence in publicly supplied drinking water in Estonia

    NASA Astrophysics Data System (ADS)

    Karro, Enn; Indermitte, Ene; Saava, Astrid; Haamer, Kadri; Marandi, Andres

    2006-06-01

    A study was undertaken to examine the content and spatial distribution of fluoride in drinking water. Water samples (735) from public water systems covering all Estonian territory were analysed using SPADNS method. In order to specify the natural source of fluoride, the chemistry data from five aquifer systems utilised for water supply were included into the study. Fluoride concentrations in tap water, to a great extent, ranged from 0.01 to 6.95 mg/l. Drinking water in southern Estonia, where terrigenous Middle-Devonian aquifer system is exploited, has a fluoride concentration lower than recommended level (0.5 mg/l), thus promoting susceptibility to dental caries. The western part of the country is supplied by water with excess fluoride content (1.5-6.9 mg/l). Groundwater abstracted for drinking purposes originates from Ordovician and Silurian carbonate rocks. The content of fluoride in Silurian-Ordovician aquifer system is associated with the groundwater abstraction depth and the main controlling factors of dissolved fluoride are the pH value and the chemical type of water.

  9. 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. PMID:23688732

  10. 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.

  11. 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.

  12. CO2 soil fluxes at bog and forest ecosystems in southern taiga of European Russia

    NASA Astrophysics Data System (ADS)

    Ivanov, Dmitrii; Ivanov, Aleksey; Vasenev, Ivan; Kurbatova, Juliya

    2015-04-01

    Bogs and spruce forests are typical natural ecosystems of the southern taiga of European Russia. They play an important role in carbon balance between soil and atmosphere. In the Central Forest Reserve (33°00' E, 56°30' N) for over 15 years conduct research of these processes. One of the research methods of CO2 emissions is the chamber method, which allows to analyze the local variation of the intensity of fluxes and its depending of the type of vegetation, microrelief and meteorological parameters. Period of measurements was 5 months - from June to November 2013-2014. In the bog were investigated 3 areas - pine boggy forest, as well as hummocks and hollows in the middle of bog. As the forest ecosystem was chosen paludified shallow-peat spruce forest. From the data obtained it can be concluded that in all ecosystems were observed 2 periods with a minimum values of CO2 emission: the first - in early July, associated with a high level of ground water and decrease the intensity of decomposition of organic matter, and the second - in November, associated with natural processes and seasonal cooling. The average intensity of CO2 emissions in summer-autumn season between all ecosystems varied greatly: in the boggy pine forest - 500 mgCO2/m2*h), hummocks - 550 mgCO2/m2*h, hollows - 290 mgCO2/m2*h) and paludified shallow-peat spruce forest - 750 mgCO2/m2*h. Based on these researches, it was found that the intensity of CO2 emissions significantly below in the bog than in paludified shallow-peat spruce forest because it is limited by the level of ground water. In the paludified shallow-peat spruce forest, fluxes are more depend on soil temperature and less on the groundwater level.

  13. Analysis of the varved clay accumulation in the Pärnu Bay area, Estonia

    NASA Astrophysics Data System (ADS)

    Kalvans, Andis; Hang, Tiit

    2015-04-01

    Varved clays are commonly found glaciolacustrine sediments representing high-resolution environmental archives of the deglaciation events. We examine varve formation in the Baltic Ice Lake at the Pärnu Bay area, Estonia, during the deglaciation of the last Scandinavian glaciation from the region. The data set of Hang and Kohv (2013) spanning 584 years is used. Analysis of the spatial variation of the seasonal layer thickness distribution based on 26 sediment cores and sub-varve resolution grain size analysis from a single section was performed. The Baltic Ice Lake water level reconstruction indicates that the water depth at the study region was up to 80 m (Rosentau et al., 2009). It is found that during the first ~130 years after the ice retreat the summer sedimentation was dominated by sediment loaded underflows emanating form the ice margin: summer layer thickness is strongly positively correlated with water depth. The winter layer thickness during this period does not demonstrate significant correlation with water depth suggesting that the simple raining-out of the suspended material from a water column was complicated by water circulation. Ice retreat from the Pandivere-Neva line of the marginal formations just north from study area took place during the interval from 96 to 130 local varve years. During the transition marked shift from proglacial to distal sedimentary environment is observed: the summer layer thickens decreased dramatically and it's thickens is markedly higher in the area close to the ice margin. The winter layer thickens becomes strongly correlated to the water depth, suggesting that the simple sedimentation model with no water circulation and addition of no new sediments is valid. The grain size data is used to estimate the "terminal grain size" - the size of the larges particles sedimented at the top of the winter layer. Provided that no significant water circulation took place during the winter, the terminal grain size will be controlled

  14. 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.

  15. 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.

  16. 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

  17. 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.

  18. 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

  19. 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

  20. Hospitalised neonates in Estonia commonly receive potentially harmful excipients

    PubMed Central

    2012-01-01

    Background Information on the neonatal exposure to excipients is limited. Our aim was to describe the extent of excipient intake by Estonian neonates; to classify the excipients according to potential neonatal toxicity and thereby to measure the extent of exposure of neonates to potentially harmful excipients. Methods A prospective cohort study that recorded all medicines prescribed to patients aged below 28 days admitted to Tartu University Hospital from 01.02-01.08 2008 and to Tallinn Children’s Hospital from 01.02- 01.08 2009 was conducted. Excipients were identified from Summaries of Product Characteristics and classified according to toxicity following a literature review. Results 1961 prescriptions comprising 107 medicines were written for 348/490 neonates admitted. A total of 123 excipients were found in 1620 (83%) prescriptions and 93 (87%) medicines. 47 (38%) of these excipients were classified as potentially or known to be harmful to neonates. Most neonates (97%) received at least one medicine (median number 2) with potentially or known to be harmful excipient. Parabens were the most commonly used known to be harmful excipients and sodium metabisulphite the most commonly used potentially harmful excipient, received by 343 (99%) and 297 (85%) of treated neonates, respectively. Conclusions Hospitalised neonates in Estonia are commonly receiving a wide range of excipients with their medication. Quantitative information about excipients should be made available to pharmacists and neonatologists helping them to take into account excipient issues when selecting medicines and to monitor for adverse effects if administration of medicines containing excipients is unavoidable. PMID:22931304

  1. 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.

  2. 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

  3. 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. PMID:26971209

  4. 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

  5. When Public Acts Like Private: The Failure of Estonia's School Choice Mechanism

    ERIC Educational Resources Information Center

    Poder, Kaire; Lauri, Triin

    2014-01-01

    This article aims to show the segregating effect of the market-like matching of students and schools at the basic school level. The natural experiment case is Tallinn, the capital of Estonia. The current school choice mechanism applied in this case is based on entrance tests. There are increasingly over-subscribed intra-catchment area public…

  6. Family- and Classroom-Related Factors and Mother-Kindergarten Teacher Trust in Estonia and Finland

    ERIC Educational Resources Information Center

    Kikas, Eve; Lerkkanen, Marja-Kristiina; Pakarinen, Eija; Poikonen, Pirjo-Liisa

    2016-01-01

    This study examined the role of family-related (mother's education, depressive symptoms and child's gender) and kindergarten-related (teacher's experience, teaching practices and class size) factors in mothers' and teachers' mutual trust in Estonia and Finland. Six hundred eighteen (206 Estonian and 412 Finnish) mothers of kindergarten children…

  7. Will Choice Hurt? Compared to What? A School Choice Experiment in Estonia

    ERIC Educational Resources Information Center

    Põder, Kaire; Lauri, Triin

    2014-01-01

    This article presents the empirical analysis of the effects of a school choice policy in Estonia. The article shows that relying on markets and giving autonomy to the schools over student selection will produce admission tests, even at the elementary school level. This article's contribution is to show that a school choice policy experiment…

  8. Explaining the Difference between PISA 2009 Reading Scores in Finland and Estonia

    ERIC Educational Resources Information Center

    Mikk, Jaan

    2015-01-01

    The aim of the study was to explain the difference between the Programme for International Student Assessment (PISA) 2009 reading results for Finland and Estonia using characteristics of teaching and learning, and characteristics of the overall development of these countries. PISA data were collected via a reading test and student questionnaires…

  9. Learning and Developing as a University Teacher: Narratives of Early Career Academics in Estonia

    ERIC Educational Resources Information Center

    Remmik, Marvi; Karm, Mari; Lepp, Liina

    2013-01-01

    In recent years the higher education context in Estonia, as in most European countries, has changed a lot. All changes have an impact on university teachers' practice and their work organisation, and are presenting new challenges. The current research aims at developing an understanding of Estonian early career academics' professional…

  10. Alternative Civil Enculturation: Political Disenchantment and Civic Attitudes in Minority Schools in Estonia, Latvia, and Slovakia

    ERIC Educational Resources Information Center

    Golubeva, Maria; Austers, Ivars

    2011-01-01

    The article investigates the ways in which minority schools in Latvia, Estonia, and Slovakia resist the dominant narratives of nation and citizenship and provide an alternative model of civil enculturation for students. It provides evidence to support the hypothesis that differences between competing narratives of statehood and nationhood among…

  11. University Studies as a Side Job: Causes and Consequences of Massive Student Employment in Estonia

    ERIC Educational Resources Information Center

    Beerkens, Maarja; Magi, Eve; Lill, Liis

    2011-01-01

    Student employment is increasingly common in many countries. Compared to earlier decades, not only more students work but they also work longer hours. Among European countries Estonia is one of the clear "leaders" in student employment. This study uses survey data from 2,496 students in Estonian public and private universities to examine the…

  12. The National Status of the Preparation of School Psychologists in Estonia

    ERIC Educational Resources Information Center

    Kikas, Eve

    2014-01-01

    Estonia is a small republic that has undergone several big societal changes (from belonging to the Soviet Union to becoming a free republic, and the process of integrating into the European Union) during the last several decades. Psychology has been taught as a separate discipline starting from 1968, but its content has been changed from very…

  13. Education Policy as Normative Discourse and Negotiated Meanings: Engaging the Holocaust in Estonia

    ERIC Educational Resources Information Center

    Stevick, E. Doyle

    2010-01-01

    This article uses a socio-cultural approach to analyze the formation and implementation of Estonia's Holocaust Day Policy, a day of both commemoration for victims of the Holocaust and other crimes against humanity, and education about the Holocaust. It investigates both the multi-level development of the policy in light of external pressure (from…

  14. When Failing Is the Only Option: Explaining Failure to Finish PhDs in Estonia

    ERIC Educational Resources Information Center

    Vassil, Kristjan; Solvak, Mihkel

    2012-01-01

    That PhD candidates fail to graduate on time in large numbers across a number of countries is a well-known fact. An extreme example is Estonia, where according to some estimates less than a third of PhD students complete their studies on time. A number of studies have addressed the likely reasons for such behavior, both comparatively and…

  15. Estonian Language Competencies for Peace Corps Volunteers in the Republic of Estonia.

    ERIC Educational Resources Information Center

    Ets, Tiina K.

    This guide is designed for Estonian language training of Peace Corps workers in Estonia, is intended for use in a competency-based language training program, and reflects daily communication needs in that context. It consists of 52 lessons, each addressing a specific language competency, organized in 14 topical units. An introductory section gives…

  16. Development of Indicators for Educational Planning: Brazil, Cambodia, Estonia, Gambia, Lithuania, Thailand.

    ERIC Educational Resources Information Center

    United Nations Educational, Scientific, and Cultural Organization, Paris (France). International Inst. for Educational Planning.

    This publication presents the outcomes of a distance education course on development and dissemination of indicators used for educational planning. The course took place from November 2000 to February 2001 and was attended by representatives from the ministries of education of Brazil, Cambodia, Estonia, Gambia, Lithuania, and Thailand. The overall…

  17. An Examination of the Flynn Effect in the National Intelligence Test in Estonia

    ERIC Educational Resources Information Center

    Shiu, William

    2012-01-01

    This study examined the Flynn Effect (FE; i.e., the rise in IQ scores over time) in Estonia from Scale B of the National Intelligence Test using both classical test theory (CTT) and item response theory (IRT) methods. Secondary data from two cohorts (1934, n = 890 and 2006, n = 913) of students were analyzed, using both classical test theory (CTT)…

  18. E-Learning as Innovation: Exploring Innovativeness of the VET Teachers' Community in Estonia

    ERIC Educational Resources Information Center

    Loogma, Krista; Kruusvall, Juri; Umarik, Meril

    2012-01-01

    In this article, the acceptance of e-learning by teachers of vocational secondary and professional higher education institutions (hereafter: VET teachers) in Estonia has been analysed. The analysis is based on questionnaire study, carried out in 2007. The theoretical framework of the article has been inspired by Everett Rogers' innovation…

  19. Family medicine as a model of transition from academic medicine to academic health care: Estonia's experience.

    PubMed

    Maaroos, Heidi-Ingrid

    2004-10-01

    This paper presents the development of academic family medicine in an environment of traditional academic medicine at the Tartu University, Estonia. The introduction of university family medicine teachers to everyday practice and practitioners to academic teaching and research helps bridge the gap between theory and practice, and it shows changed approach to academic medicine. PMID:15495281

  20. Between Consumerism and Protectionism: Attitudes towards Children, Consumption and the Media in Estonia

    ERIC Educational Resources Information Center

    Keller, Margit; Kalmus, Veronika

    2009-01-01

    This study measures attitudes towards children's vulnerability or empowerment within consumer culture, based on data from a representative population survey (N = 1475) conducted in Estonia in 2005. The study use indices comprised of assessments of consumption practices and assertions pertaining to the "endangered vs empowered child" debate in…

  1. Economic, Educational and Cultural Predictors of Science Learning in Lithuania and Estonia

    ERIC Educational Resources Information Center

    Mikk, Jaan

    2007-01-01

    The aim of the research was to assess the economic, educational and cultural predictors of the TIMSS 2003 science test results in Lithuania and Estonia. The data for the research were received from the TIMSS 2003 User Guide for the International Database. The Spearman rank correlation coefficients, calculated on the students' level and the schools…

  2. When Language becomes Power: Russian-Speaking Teachers in the Bilingual General Education System in Estonia

    ERIC Educational Resources Information Center

    Kiilo, Tatjana; Kutsar, Dagmar

    2012-01-01

    After the re-establishment of independent Estonian statehood in 1991, Russian lost its privileges as the dominant and official language in Estonia, and Estonian continued as the only official language. This paper attempts to map the position of a Russian-speaking teacher within the sociological categories of power and language, based on the…

  3. Postglacial land uplift in Estonia based on four precise levelings

    NASA Astrophysics Data System (ADS)

    Kall, Tarmo; Oja, Tõnis; Tänavsuu, Kalmer

    2014-01-01

    The vertical velocities of the fundamental benchmarks of Estonian 1st order leveling network were estimated, based on the four precise leveling campaigns from 1933 to 2010. The kinematic least squares adjustment of the network was used, where heights and velocities were introduced as unknown parameters. For detection of outliers, Baarda's data snooping method was applied. Estimation of variance components by the Helmert's and the IAUE methods provided realistic weights in the network adjustment and revealed also that the observation errors of the first three levelings are up to 3 times larger than was assumed a priori. To obtain apparent uplift rates and fix velocity in kinematic adjustment, the velocity value + 2.1 mm/yr of the Ristna tide gauge on island Hiiumaa was transferred to the nearest stable benchmark by using precise levelings from tide gauge to the national height network. Average standard deviation of velocities at benchmarks was estimated to be ± 0.5 mm/yr. Based on apparent vertical velocities of the benchmarks, an interpolated land uplift surface was created using “kriging” and “minimum curvature” gridding methods. Although the two methods gave similar surfaces (RMS of differences was below ± 0.1 mm/yr), the kriging solution was used in comparison with the results of the earlier studies. The uncertainty of new velocity surface was estimated to be ± 0.5 to ± 0.7 mm/yr. The new land uplift model fits well with the Fennoscandian land uplift model NKG2005LU. The RMS of the differences was ± 0.2 mm/yr. Good agreement was also confirmed with the earlier land uplift maps of Estonia (RMS of differences ± 0.6 mm/yr). However, clear disagreement was noticed when tide gauge observations from several studies were used in comparison (RMS of differences up to ± 1.0 mm/yr). Apparently, different velocity solutions of Estonian tide gauges are systematically biased; the reasons for these biases need further investigation.

  4. 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.

  5. 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

  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. 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

  8. The impact of peat harvesting and natural regeneration on the water balance of an abandoned cutover bog, Quebec

    NASA Astrophysics Data System (ADS)

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

    2001-02-01

    Harvested sites rarely return to functional ecosystems after abandonment because drainage and peat extraction lower the water table and expose relatively decomposed peat, which is hydrologically unsuitable for Sphagnum moss re-establishment. Some natural regeneration of Sphagnum has occurred in isolated pockets on traditionally harvested (block-cut) sites, for reasons that are poorly understood, but are related to natural functions that regulate runoff and evaporation. This study evaluates the water balance of a naturally regenerated cutover bog and compares it with a nearby natural bog of similar size and origin, near Riviere du Loup, Quebec. Water balance results indicated that evapotranspiration was the major water loss from the harvested bog, comprising 92 and 84% of total outputs (2·9 mm day-1) during the 1997 and 1998 seasons, respectively. Despite denser tree cover at the harvested site, evapotranspiration from the natural bog was similar, although less spatially variable. At the harvested site, evaporative losses ranged from 1·9 mm day-1 on raised baulks and roads to 3·6 mm day-1 from moist surfaces with Sphagnum. Although about half of the ditches were inactive or operating at only a fraction of their original efficiency, runoff was still significant at 12 and 24% of precipitation during the 1997 and 1998 study seasons, respectively. This compares with negligible rates of runoff at the natural bog. Thus the cutover bog, although abandoned over 25 years ago, has not regained its hydrological function. This is both a cause and effect of its inability to support renewed Sphagnum regeneration. Without suitable management (e.g. blocking ditches), this site is not likely to improve for a very long time.

  9. 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

  10. 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.

  11. 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.

  12. 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. PMID:25739499

  13. 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.

  14. 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.

  15. 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.

  16. 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

  17. Comparison of different methods to determine the degree of peat decomposition in peat bogs

    NASA Astrophysics Data System (ADS)

    Biester, H.; Knorr, K.-H.; Schellekens, J.; Basler, A.; Hermanns, Y.-M.

    2014-05-01

    Peat humification or decomposition is a frequently used proxy to extract past time changes in hydrology and climate from peat bogs. During the past century several methods to determine changes in peat decomposition have been introduced. Most of these methods are operationally defined only and the chemical changes underlying the decomposition process are often poorly understood and lack validation. Owing to the chemically undefined nature of many humification analyses the comparison of results obtained by different methods is difficult. In this study we compared changes in peat decomposition proxies in cores of two peat bogs (Königsmoor, KK; Kleines Rotes Bruch, KRB) from the Harz Mountains (Germany) using C / N ratios, Fourier transform infrared spectra absorption (FTIR) intensities, Rock Eva® oxygen and hydrogen indices, δ13C and δ15N isotopic signatures and UV-absorption (UV-ABS) of NaOH peat extracts. In order to explain parallels and discrepancies between these methods, one of the cores was additionally analysed by pyrolysis gas chromatography mass spectrometry (pyrolysis-GC-MS). Pyrolysis-GC-MS data provide detailed information on a molecular level, which allows differentiation of both changes attributed to decomposition processes and changes in vegetation. Principal component analysis was used to identify and separate the effects of changes in vegetation pattern and decomposition processes because both may occur simultaneously upon changes in bog hydrology. Records of decomposition proxies show similar historical development at both sites, indicating external forcing such as climate as controlling the process. All decomposition proxies except UV-ABS and δ15N isotopes show similar patterns in their records and reflect to different extents signals of decomposition. The molecular composition of the KK core reveals that these changes are mainly attributed to decomposition processes and to a lesser extent to changes in vegetation. Changes in the molecular

  18. 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

  19. Single and double sexual standards in Finland, Estonia, and St. Petersburg.

    PubMed

    Haavio-Mannila, Elina; Kontula, Osmo

    2003-02-01

    The sexual revolution and fight for gender equality began in the West during the 1960s but did not reach the Soviet Union until the late 1980s. Using survey data from nationally representative samples from Finland in 1971, 1992, and 1999 and from two former Soviet areas, Estonia in 2000 and St. Petersburg in 1996, we investigated the following: (a) differences across decades and countries in acceptance of the sexual double standard (SDS) in attitudes toward marital infidelity and women's initiating sex; and (b) the relationship between the SDS and sexual satisfaction. Results show that Finland in the 1990s was more egalitarian than Finland in 1971, St. Petersburg in 1996, or Estonia in 2000. Egalitarian sexual attitudes were positively related to sexual satisfaction. PMID:12806530

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

    NASA Astrophysics Data System (ADS)

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

    2008-12-01

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

  1. 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.

  2. 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. PMID:27032635

  3. How Do Preschool Children Engage Each Other in Dialogue in Finland, Estonia and Sweden?

    ERIC Educational Resources Information Center

    Tryggvason, Marja-Terttu; Tulviste, Tiia; De Geer, Boel

    2008-01-01

    The present study compares preschool children in Finland, Estonia and Sweden regarding linguistic structures with which children in dyads elicited talk from each other in a naturalistic play activity. Nineteen Finnish (mean age 5.1), 19 Estonian (mean age 5.4) and 17 Swedish (mean age 5.1) same-sex pairs were video-recorded by a native researcher.…

  4. Survey of the Presence of Toxocara spp. Eggs in Dog Feces in Tartu, Estonia.

    PubMed

    Lassen, Brian; Jokelainen, Pikka

    2016-03-01

    Several zoonotic pathogens are shed in the feces of infected animals. If they are allowed to contaminate the environment, they cause a public health concern. In this study, we investigated the presence of Toxocara spp. eggs in dog feces in the urban area of Tartu, Estonia. Samples were collected by veterinary students in 2014 and examined using a modified concentration-flotation technique. Toxocara spp. eggs were detected by microscopy in 4 (1.7%) out of 234 canine fecal samples. PMID:26854385

  5. Mammography use and mode of detection among breast cancer patients in Estonia.

    PubMed

    Innos, Kaire; Valvere, Vahur; Padrik, Peeter; Eelma, Evelyn; Kütner, Riina; Lehtsaar, Jaak; Tekkel, Mare

    2016-01-01

    The aim of this study was to examine past mammography use and mode of detection among breast cancer (BC) patients in Estonia, a country that has low screening coverage and high BC mortality. Women newly diagnosed with primary BC in Estonia in 2008-2010 were interviewed. Determinants of past mammography use and the detection of BC by mammography were studied using multivariate logistic regression. Among 977 participants, almost half reported no mammograms prior to the detection of BC. Overall, 22% of the cases were detected by mammography (16% by screening mammography). Detection by mammography was strongly related to age, past mammography use, and obesity. Among cases detected by mammography, 10% were stage III/IV at diagnosis (32% among cases detected by other modes). This study showed low mammography utilization and high rate of self-detection of BC in Estonia. Increased detection by mammography would help diagnose the disease at an earlier stage and consequently avoid premature BC deaths. Efforts should be undertaken to increase participation in screening and improve the availability of mammography among older and high-risk women. The results are likely to be relevant for other countries and population groups with low screening coverage. PMID:26327255

  6. Summer methane fluxes from a boreal bog in northern Quebec, Canada, using eddy covariance measurements

    NASA Astrophysics Data System (ADS)

    Nadeau, Daniel F.; Rousseau, Alain N.; Coursolle, Carole; Margolis, Hank A.; Parlange, Marc B.

    2013-12-01

    A boreal bog located in the James Bay lowlands, Canada, was instrumented with an open-path gas analyzer to monitor the turbulent fluxes of methane throughout the summer of 2012. The mostly continuous eddy covariance measurements permitted the study of methane dynamics at the hourly, daily and seasonal scales. To exclude data segments for which the biological methane fluxes were underestimated due to inefficient atmospheric transport under stable stratification, we applied a novel approach based on both the atmospheric stability parameter ζ = z/L and the friction velocity u∗, where z is the measurement height and L the Obukhov length. The field measurements revealed the existence of at least one sustained ebullition event, triggered by low barometric pressures, a declining water table and increasing mechanical turbulence - suggesting that large-scale release of methane bubbles can be an important transport mechanism of methane in boreal bogs. The validity of similarity scaling for atmospheric methane under convective conditions was also assessed and the normalized standard deviations of methane concentrations did not scale well with ζ, highlighting the heterogeneity in natural methane production and release across the bog. Overall the hourly emissions ranged between -2.0 and 32.1 mg CH4 m-2 h-1, with a summertime mean of 2.4 mg CH4 m-2 h-1. At the daily scale, the two main controls on methane emissions were found to be the water table position and the peat temperature at 0.3 m under the surface. Contrary to other studies, seasonal methane emissions peaked when the water table was at its maximum distance from the surface, around mid-August. No clear diurnal pattern could be found in methane emissions, indicating that methane was produced quite deep within the peat. The seasonal emissions were estimated at 4.4 g CH4 m-2, and compared well with other observations over similar landscapes using different measurement techniques. Given that methane releases and

  7. 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

  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. PMID:26851760

  9. 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.

  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. 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. PMID:25874369

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

    NASA Astrophysics Data System (ADS)

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

    2015-04-01

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

  13. Comparison of different methods to determine the degree of peat decomposition in peat bogs

    NASA Astrophysics Data System (ADS)

    Biester, H.; Knorr, K.-H.; Schellekens, J.; Basler, A.; Hermanns, Y.-M.

    2013-11-01

    Peat humification or decomposition is a frequently used proxy to extract past time changes in hydrology and climate from peat bogs. During the past century several methods to determine changes in peat decomposition have been introduced. Most of these methods are operationally defined only and the chemical changes underlying the decomposition process are often poorly understood and lack validation. Due to the chemically undefined nature of many humification analyses the comparison of results obtained by different methods is difficult if not misleading. In this study we compared changes in peat decomposition in cores of two peat bogs (Königsmoor (KK), Kleines Rotes Bruch, KRB) from the Harz Mountains (Germany) using C / N ratios, Fourier Transform Infrared spectra absorption (FTIR) intensities, Rock Eval® oxygen- and hydrogen indices, δ13C and δ15N isotopic signatures and UV-absorption of NaOH peat extracts. In addition, one of the cores was analysed for changes in the peat's molecular composition using pyrolysis gas chromatography mass spectrometry (pyrolysis-GC-MS). Records of decomposition proxies show similar historical development at both sites, indicating external forcing such as climate as controlling process. Moreover, all decomposition proxies except UV-ABS and δ15N isotopes show similar patterns in their records and thus reflect in different extents signals of decomposition. Pyrolysis-GC-MS analyses of the KK core reveal that changes in peat molecular chemistry are mainly attributed to decomposition processes and to a lesser extend to changes in vegetation. Changes in the abundance of molecular compounds indicate that peat decomposition in the KK bog is mainly characterized by preferential decomposition of phenols and polysaccharides and relative enrichment of aliphatics during drier periods. Enrichment of lignin and other aromatics during decomposition was also observed but showed less variation, and presumably reflects changes in vegetation

  14. 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.

  15. 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.

  16. 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

  17. 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.

  18. 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. PMID:24630445

  19. 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.

  20. 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. PMID:25752706

  1. 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. PMID:26849121

  2. 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

  3. Comparative Study: Impact of Family, School, and Students Factors on Students Achievements in Reading in Developed (Estonia) and Developing (Azerbaijan) Countries

    ERIC Educational Resources Information Center

    Shukakidze, Berika

    2013-01-01

    The work is based on PISA 2009 International Assessment Study. Two counties were selected: a developed country, Estonia and a developing country, Azerbaijan. The following Datum was used for statistical analysis: students average scores in reading (162 schools, 4 600 students from Azerbaijan; 17 schools, 4 923 students from Estonia). The work is…

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

    NASA Astrophysics Data System (ADS)

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

    2014-12-01

    About 30% of the landscape of northern Alberta, Canada is occupied by peatlands, which persist at the low end range of both mean annual precipitation (<500 mm/yr) and mean annual atmospheric nitrogen (N) deposition (< 1 kg/ha/yr) across which peatlands are found globally. Ombrotrophic bogs in this region function as a net sink for atmospheric CO2 of over 75 g/m2/yr, taking into consideration changes in CO2 sink strength as a function of time since fire. In addition to fire, a new disturbance is emerging in the Athabasca Oil Sands Region (AOSR) of northern Alberta, where development of the oil sands resource has increased atmospheric N deposition to as much as 2.5 kg/ha/yr. To examine the effects of elevated N deposition on bog C cycling, we experimentally applied N (as NH4NO3 solutions) to replicated plots at levels equivalent to 0 (water added with no N), 10, and 20 kg/ha/yr, and controls (no waher, no N added) at five bog sites, aged at 2, 12, 32, 73, and 113 years since fire in 2013 (6 plots per N treatment per site). Understory net ecosystem exchange of CO2 (NEE) was measured repeatedly throughout the 2013 and 2014 growing season (and in 2011 and 2012 at the most recently burned site) using the closed chamber approach. Using a rectangular hyperbola equation to characterize NEE as a function of photosynthetically active radiation (PAR) and near-surface air temperature (T), monthly and annual NEE was estimated based on hourly measurements of PAR and T at each site. Across all sites, a general pattern emerged that N additions enhanced the net CO2 sink strength of the bogs, with no effect on ecosystem respiration. Net primary production of Sphagnum fuscum, the dominant peat-forming moss, was not affected by N addition, suggesting that the overall response of NEE to N addition is the result of enhanced growth of ericaceous shrubs. These findings suggest that while elevated N deposition in the AOSR may enhance the strength of the overall CO2 sink of bogs in the short

  5. The supply of trace elements from the atmosphere recorded in a natural archive by the example of the Ilas ombrotrophic bog in the White Sea drainage basin

    NASA Astrophysics Data System (ADS)

    Shevchenko, V. P.; Kusnetsov, O. L.; Politova, N. V.; Zaretskaya, N. E.; Kutenkov, S. A.; Lisitzin, A. P.; Pokrovsky, O. S.

    2015-12-01

    The results of studies are presented for the elemental composition of peat from the Ilas ombrotrophic bog (White Sea drainage basin). The calculations of enrichment factors of trace elements over the section of the bog peat relatively to the average composition of the Earth's continental crust showed that the concentrations of most of chemical elements is determined by the contributions of lithogenic and biogenic sources, and the content of trace elements is equal to the background level. Enrichment growth since the beginning of intense development of European industry until the early 21th century was revealed only for Zn, Sb, Pb, and Cd. These elements were supplied to the bog resulting from long-range air transport and precipitation from the atmosphere. No pronounced heavy-metal contamination caused by the Arkhangelsk agglomeration was revealed for the peat in the Ilas bog.

  6. 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.

  7. 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.

  8. 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.

  9. 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

  10. Amber bearing deposit in SW Saaremaa, Estonia - sedimentary environment and palaeogeography

    NASA Astrophysics Data System (ADS)

    Post, Triine; Ots, Mirja; Rosentau, Alar

    2015-04-01

    The paper describes a deposit of natural amber found form Estonia. Finds of natural amber are important in the context of the Bronze Age archaeology, because the amount of Bronze Age archaeological amber found in Estonia is very small. Most of the amber is from the Late Bronze Age and is mainly discovered from the fortified settlements in Saaremaa, some also from burials of the same time. Now, the discovery of the deposit of natural amber in the island of Saaremaa makes us reconsider the general opinion that all archaeological amber items found in Estonia have been imported. The aim of this study is to clarify the origin and age of the natural amber using scientific methods. A layer of buried organic matter (BOM) containing pieces of natural amber was discovered in Holocene coastal plain on Sõrve peninsula, island of Saaremaa. The BOM layer is buried under ca 90 cm-thick sandy coastal deposits and consists of remains of coastal plants and pieces of driftwood. Palaeogeographic reconstructions and sediment composition indicate that the layer was deposited in the coastal zone and buried quickly by sandy marine sediments. According to radiocarbon dating of the seeds of Polygonum lapathifolium the formation of the BOM layer remained in the Late Bronze Age (2480 ± 30 14C yr BP). Amber finds have been characterized using ATR-FTIR spectroscopy and isotope analysis of light elements (H and C) - both are referring to Baltic amber. Therefore it is probable that amber was transported to Saaremaa within organic matter from the Latvian-Lithuanian coastal zone where secondary Baltic amber deposits are widely known.

  11. High prevalence of rhinitis symptoms without allergic sensitization in Estonia and Finland

    PubMed Central

    Pallasaho, Paula; Kainu, Annette; Juusela, Maria; Meren, Mari; Sovijärvi, Anssi

    2015-01-01

    Objectives Allergic rhinitis and atopy are more common in urban than rural environments. Non-allergic rhinitis has not been studied to a great extent. We aimed to assess the relationship of rhinitis symptoms with different profiles of allergic sensitization, comparing this in rural and urban environments. Methods The study population consisted of population-based cohorts of adults aged 26–60 from Helsinki, Finland, and rural Saaremaa and urban Tallinn, Estonia. We compared the results of a structured interview and skin prick tests and assessed the risk factors for rhinitis. Results The prevalence of rhinitis symptoms with atopy was 32.7% in Helsinki, 20.8% in Tallinn, and 12.5% in Saaremaa (p<0.001). Rhinitis symptoms without atopy were found in 26.4%, 29.8%, and 29.3% (p=n.s.), respectively. In Helsinki, 87.3% of participants with atopy identified symptoms as allergic, compared to 57.0% in Tallinn and 47.5% in Saaremaa. Childhood in the countryside (OR 0.63), family history of allergic rhinitis (OR 1.89), and polysensitization (OR 15.99) were significantly associated with rhinitis symptoms with atopy in a multivariate logistic regression model. The most common sensitizers were pollens and animals in Helsinki and mites in Estonia. Exposure to environmental tobacco smoke (OR 1.50) and family history of allergic rhinitis (OR 1.70) were associated with rhinitis symptoms without atopy. Conclusion Rhinitis symptoms without allergic sensitization were common in both Finland and Estonia and were associated with environmental tobacco smoke. Family history of allergic rhinitis predisposed to rhinitis symptoms irrespective of atopy status. PMID:26557256

  12. 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.

  13. Soil carbon balance on drained and afforested transitional bog in forest research station Vesetnieki in Latvia

    NASA Astrophysics Data System (ADS)

    Lupiķis, Ainārs; Lazdiņš, Andis

    2015-04-01

    Around 0.8 mill. ha forests in Latvia are located on organic soils and 0.5 mill. ha of these forests are drained. Drainage of organic soils alters carbon stock and may has impact on the climate change. The aim of this study is to analyse the impact of drainage on a soil carbon stock in transitional bog (average growing stock before drainage 50 m3*ha-1) located in central part of Latvia in research station "Vesetnieki". Drainage was done in 1960. Average peat thickness is around 4.5 m; dominant tree species are pine (Pinus sylvestris L.) and spruce (Picea abies Karst.) with average growing stock 226 m3*ha-1 and 213 m3*ha-1. Volumetric peat samples were taken from soil surface down to 80 cm depth in 30 sample plots in drained sites and non-drained areas (transitional bog), which have been left as a control. Bulk density, carbon content in peat was determined to evaluate carbon stock changes in soil. Ground surface levelling in drained sites was done before drainage and repeatedly in 1966, 1970, 1975, 1977, 1982 and 2014 to calculate peat subsidence. The rate of peat subsidence after drainage increased rapidly, and 14 years after drainage 15.8 cm decrease of the surface level was found. The rate of the peat subsidence decreased later, and the ground level reduced by 9.9 cm in the following 40 years, reaching 25.7±3.5 cm from initial ground surface level in the 2014. The rapid decrease of the surface level after drainage can be explained by physical alters and by decomposition of the peat surface layers, however, it is not possible to assess now, which of these processes dominated. However, the significant (α=0.05) increase of the peat bulk density and carbon content in upper layers (0-80 cm) in drained sites compared to non-drained leads to conclusion that the compaction was the dominating process. Average carbon stock (0-80 cm deep soil layer) in non-drained areas is 339±29 tons*ha-1 and 513±27 tons*ha-1 in drained sites. We compared carbon stock in upper 80 cm

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

    NASA Astrophysics Data System (ADS)

    Beetz, S.; Liebersbach, H.; Glatzel, S.; Jurasinski, G.; Buczko, U.; Höper, H.

    2013-02-01

    Wetlands can either be net sinks or net sources of greenhouse gases (GHGs), depending on the mean annual water level and other factors like average annual temperature, vegetation development, and land use. Whereas drained and agriculturally used peatlands tend to be carbon dioxide (CO2) and nitrous oxide (N2O) sources but methane (CH4) sinks, restored (i.e. rewetted) peatlands rather incorporate CO2, tend to be N2O neutral and release CH4. One of the aims of peatland restoration is to decrease their global warming potential (GWP) by reducing GHG emissions. We estimated the greenhouse gas exchange of a peat bog restoration sequence over a period of 2 yr (1 July 2007-30 June 2009) in an Atlantic raised bog in northwest Germany. We set up three study sites representing different land use intensities: intensive grassland (deeply drained, mineral fertilizer, cattle manure and 4-5 cuts per year); extensive grassland (rewetted, no fertilizer or manure, up to 1 cutting per year); near-natural peat bog (almost no anthropogenic influence). Daily and annual greenhouse gas exchange was estimated based on closed-chamber measurements. CH4 and N2O fluxes were recorded bi-weekly, and net ecosystem exchange (NEE) measurements were carried out every 3-4 weeks. Annual sums of CH4 and N2O fluxes were estimated by linear interpolation while NEE was modelled. Regarding GWP, the intensive grassland site emitted 564 ± 255 g CO2-C equivalents m-2 yr-1 and 850 ± 238 g CO2-C equivalents m-2 yr-1 in the first (2007/2008) and the second (2008/2009) measuring year, respectively. The GWP of the extensive grassland amounted to -129 ± 231 g CO2-C equivalents m-2 yr-1 and 94 ± 200 g CO2-C equivalents m-2 yr-1, while it added up to 45 ± 117 g CO2-C equivalents m-2 yr-1 and -101 ± 93 g CO2-C equivalents m-2 yr-1 in 2007/08 and 2008/09 for the near-natural site. In contrast, in calendar year 2008 GWP aggregated to 441 ± 201 g CO2-C equivalents m-2 yr-1, 14 ± 162 g CO2-C equivalents m-2 yr-1

  15. The Kaali crater field and other geosites of Saaremaa Island (Estonia): the perspectives for a geopark

    NASA Astrophysics Data System (ADS)

    Raukas, Anto; Stankowski, Wojciech

    2010-04-01

    The Island of Saaremaa in Estonia offers highly spectacular geological features that belong to the most interesting in the Baltic Sea area. A unique geological monument on the island is the Kaali meteorite-crater field, formed by nine meteorite impacts. There are also attractive coastal cliffs, huge erratics, alvars (limestone areas covered by a very thin soil) and well-developed glacial and marine landforms. Limestone cliffs and shingle beaches abound with Silurian fossils and offer great opportunities to fossil collectors. The island is a prospective geopark. During the past few years, the geology of the island has become an intensely studied object of Estonian and Polish geologists.

  16. Reduction in nitrogen oxides emission on TGME-464 boiler of IRU power plant (Estonia)

    NASA Astrophysics Data System (ADS)

    Roslyakov, P. V.; Ionkin, I. L.

    2015-01-01

    The possibility for realization of measures on a reduction in nitrogen oxides emission on a TGME-464 (plant no. 2) boiler of the IRU power plant (Tallinn, Estonia) is investigated. Low-cost techno-logical measures, namely, nonstoichiometric burning and burning with the moderate controlled chemical underburning, are proposed and experimentally tested. Recommendations on the implementation of low-emission modes of burning natural gas into mode diagrams of the boiler are given. Nitrogen oxides emissions are reduced to the required level as a result of the implementation of the proposed measures.

  17. 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.

  18. Comparative characteristic of the sphagnum moss and peat of upland bogs in Siberia, Russia and central part of Germany

    NASA Astrophysics Data System (ADS)

    Mezhibor, Antonina; Podkozlin, Ivan

    2013-04-01

    This research represents the results of the ICP-MS study for the moss and peat samples from two upland bogs of Germany and one bog from Siberia, Russia (Tomsk region). Moss and upland peat are widely used for ecological studies. These substances enable to detect atmospheric pollution because of the peculiar structure of sphagnum moss. According to the obtained results, we can resume that moss and peat in Tomsk region are more enriched in such chemical elements as Cr, Fe, As, Sr, Y, Zr, Ba, La, Ce, Nd, Sm, Eu, Tb, Yb, Lu, Hf, Hg, Th, and U. The samples from Germany are more enriched in Mn, Cu, Zn, and Se. The geochemical composition of the bogs reflects the specificity of industries that pollute the atmosphere with definite chemical elements. Thus, REE, Th and U in the moss and peat of Tomsk region can originate from nuclear facility near the Tomsk city. Coal combustion in power stations can be the source of Cr, As, Sr and REE as well. Mn, Cu, Zn, and Se possibly can originate from metallurgical facilities in Germany.

  19. 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. PMID:26048060

  20. 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.

  1. 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.

  2. Water and Energy Exchanges over a Subarctic Bog in Northern Quebec, Canada

    NASA Astrophysics Data System (ADS)

    Isabelle, P.; Nadeau, D. F.; Rousseau, A. N.

    2013-12-01

    A significant fraction of the energy supply to eastern Canada and to the northeastern US comes from large hydropower plants located in the Canadian boreal shield. For instance, the La Grande River watershed near James Bay (Canada), hosts a hydropower complex producing nearly 40% of the overall peak load of Quebec. In this northern, remote and vast (≈100,000 km2) watershed, boreal forest is predominant, but wetlands (25% of the surface cover) are of key importance to the river's water budget. Unfortunately, little is known about how boreal wetlands affect regional hydrological processes, and hence, how they contribute to inflows to hydropower reservoirs. This study aims to gain a deeper understanding of evapotranspiration processes over boreal wetlands, based on field observations. The study site is a 60-ha bog (53.7°N, 78.2°W) located next to the Necopastic River, a tributary of the La Grande River. The peatland is of ombrotrophic type, meaning that it receives most of its water and nutrients from precipitation. The analysis relies on data collected by a flux tower during a field campaign throughout summer 2012., as well as detailed measurements of the water budget in this sub-watershed. One key finding is that the atmosphere is neutrally-stratified for more than 60% of the summer. The impact of this unusual feature of the atmospheric boundary layer on water vapor fluxes is carefully analyzed. As expected, eddy covariance evapotranspiration data compared well with classical formulas (Priestley-Taylor, Penman, Penman-Monteith, FAO), particularly with Priestley-Taylor. Given nearly all these formulations command direct measurements or estimations of net radiation, and that the cost of net radiometers is prohibitive, we tested the less frequently used profile method, which simply requires one or two additional measurement levels of wind speed, temperature and humidity. The latter method led to promising results, especially considering its ease of implementation

  3. 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

    methanogenesis decreasing to 0 near a critical Gibbs free energy of about -27 KJ mol-1. The results thus suggest that, even in absence of inorganic electron acceptors, respiration rates in peat bogs are likely higher near the redox interface to the atmosphere due to lower respiration endproduct concentrations. Similar effects ensue when rates of transport are elevated or pools of CO2 and CH4 are eliminated. With decomposition being constrained, peat bog growth may occur longer than previously thought.

  4. Seasonal and interannual variation in water vapor and heat fluxes in a West Siberian continental bog

    NASA Astrophysics Data System (ADS)

    Shimoyama, K.; Hiyama, T.; Fukushima, Y.; Inoue, G.

    2003-10-01

    The seasonal and interannual variation in the energy fluxes of a West Siberian continental bog were measured from April to October in 1999 and 2000 using the eddy covariance method. The energy balance closure rate (=[sensible + latent heat fluxes]/[available energy]) ranged from ˜0.8 to 0.9 and showed a better energy balance and less scattering using the soil heat flux estimated from an area-averaged soil thermal parameter rather than from a plot-based measurement. The net radiation (Rn) increased drastically after snowmelt because the surface albedo (a) dropped from its highest value to its lowest value over the course of the snowmelt. The snowmelt water raised the water table (zwt) to its highest level; it then gradually decreased. The seasonal and interannual variation in a, which ranged from 0.09-0.19, depended on zwt, because surface wetness was closely related to zwt through the capillary uptake of Sphagnum moss. The seasonal variation in the latent heat flux (lE) was similar to that in Rn. The largest lE was observed in the middle of June, and was ˜120 Wm-2 (4.2 mm d-1) in both years. Conversely, the sensible heat flux (H) did not show an obvious seasonal pattern and was lower than lE during the growing season. The Bowen ratio (Br) in the early growing season was 0.57 and 0.60, and the values in the peak growing season were 0.65 and 0.78, in 1999 and 2000, respectively. The lower Br was related to the higher zwt; specifically, it was due to the wetter surface conditions. An interannual comparison of the monthly mean atmospheric water vapor deficit (δe) and lE showed a significant relationship with a higher lE observed in the year with a higher δe. Therefore in the bog studied the interannual variation in the water vapor flux was controlled mainly by zwt and δe.

  5. 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

  6. 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

  7. Mercury in a spanish peat bog: archive of climate change and atmospheric metal deposition

    PubMed

    Martinez-Cortizas; Pontevedra-Pombal; Garcia-Rodeja; Novoa-Munoz; Shotyk

    1999-05-01

    A peat core from a bog in northwest Spain provides a record of the net accumulation of atmospheric mercury since 4000 radiocarbon years before the present. It was found that cold climates promoted an enhanced accumulation and the preservation of mercury with low thermal stability, and warm climates were characterized by a lower accumulation and the predominance of mercury with moderate to high thermal stability. This record can be separated into natural and anthropogenic components. The substantial anthropogenic mercury component began approximately 2500 radiocarbon years before the present, which is near the time of the onset of mercury mining in Spain. Anthropogenic mercury has dominated the deposition record since the Islamic period (8th to 11th centuries A.D.). The results shown here have implications for the global mercury cycle and also imply that the thermal lability of the accumulated mercury can be used not only to quantify the effects of human activity, but also as a new tool for quantitative paleotemperature reconstruction. PMID:10320369

  8. 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.

  9. 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)). PMID:20154331

  10. Interactions between peat and salt-contaminated runoff in Alton Bog, Maine, USA

    NASA Astrophysics Data System (ADS)

    Pugh, Alexander L.; Norton, Stephen A.; Schauffler, Molly; Jacobson, George L.; Kahl, Jeffrey S.; Brutsaert, Willem F.; Mason, Charles F.

    1996-07-01

    Year round, concentrations of base cations (Ca, Mg, Na, and K) and Cl - in surface and groundwater decline exponentially away from Interstate 95, a four-lane asphalt highway which bisects Alton Bog, a poor fen in Penobscot County, Maine, USA. The increased concentrations close to the highway are caused primarily by runoff of road-salt and weathering products of road-bed fill. Concentration ratios, constant with time, between base cations and H + at individual sites suggest that cation exchange reactions between peat and water achieve a state of equilibrium. These ratios change systematically with increasing distance from the highway, indicating systematic changes in the character of the peat exchange surfaces. The major change is a decrease in the occupancy of exchange sites by Na away from the road. These relationships and inferred processes have been duplicated with laboratory experiments. Base saturation of the peat, dominated by Ca, decreases with distance from the highway. Thus, in the short term, peat-water equilibration exerts strong controls on the water chemistry, particularly ion ratios. Long term exposure to elevated concentrations of Ca, Mg, and NaCl in the shallow ground waters has altered the peat chemistry. Availability of plant nutrients (Ca, Mg, and K) has been generally increased by the weathering of road-bed fill and equilibration of the NaCl salt with the peat.