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| 3. |
- Buckland, Philip I., 1973-
(author)
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The Bugs Coleopteran Ecology Package (BugsCEP) database : 1000 sites and half a million fossils later
- 2014
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In: Quaternary International. - : Elsevier. - 1040-6182 .- 1873-4553. ; 341, s. 272-282
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Journal article (peer-reviewed)abstract
- The Bugs database project started in the late 1980s as what would now be considered a relatively simple system, albeit advanced for its time, linking fossil beetle species lists to modern habitat and distribution information. Since then, Bugs has grown into a complex database of fossils records, habitat and distribution data, dating and climate reference data wrapped into an advanced software analysis package. At the time of writing, the database contains raw data and metadata for 1124 sites, and Russell Coope directly contributed to the analysis of over 154 (14%) of them, some 98790 identifications published in 231 publications. Such quantifications are infeasible without databases, and the analytical power of combining a database of modern and fossil insects with analysis tools is potentially immense for numerous areas of science ranging from conservation to Quaternary geology.BugsCEP, The Bugs Coleopteran Ecology Package, is the latest incarnation of the Bugs database project. Released in 2007, the database is continually added too and is available for free download from http://www.bugscep.com. The software tools include quantitative habitat reconstruction and visualisation, correlation matrices, MCR climate reconstruction, searching by habitat and retrieving, among other things, a list of taxa known from the selected habitat types. It also provides a system for entering, storing and managing palaeoentomological data as well as a number of expert system like reporting facilities.Work is underway to create an online version of BugsCEP, implemented through the Strategic Environmental Archaeology Database (SEAD) project (http://www.sead.se). The aim is to provide more direct access to the latest data, a community orientated updating system, and integration with other proxy data. Eventually, the tools available in the offline BugsCEP will be duplicated and Bugs will be entirely in the web.This paper summarises aspects of the current scope, capabilities and applications of the BugsCEP database and software, with special reference to and quantifications of the contributions of Russell Coope to the field of palaeoentomology as represented in the database. The paper also serves to illustrate the potential for the use of BugsCEP in biographical studies, and discusses some of the issues relating to the use of large scale sources of quantitative data.All datasets used in this article are available through the current version of BugsCEP available at http://www.bugscep.com.
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| 6. |
- Kylander, Malin, 1977-, et al.
(author)
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A novel geochemical approach to paleorecords of dust deposition and effective humidity: 8500 years of peat accumulation at Store Mosse (the "Great Bog") , Sweden )
- 2013
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In: Quaternary Science Reviews. - : Elsevier BV. - 0277-3791 .- 1873-457X. ; 69, s. 69-82
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Journal article (peer-reviewed)abstract
- Both bog surface wetness and atmospheric dust deposition are intricately linked to changes in the hydrological cycle and pairing these types of records at the same site provides complementary information. Here a peat core from Store Mosse in southern Sweden covering the last 8500 years was used to make a high-resolution paleoclimate reconstruction based on a combination of bog development, colourimetric humification and inorganic geochemistry data. The coupling of Principal Component Analysis with changepoint modelling allowed for precise linking of changes in bog surface wetness and dust deposition records.A long-term trend towards warm (and possibly wet) conditions starts ca 8150 cal yr BP and culminates with the most pronounced conditions from 6900 to 6600 cal yr BP. The most significant arid period at Store Mosse occurred between 6500 and 5600 cal yr BP during which dust deposition was significantly higher. Wetter conditions dominate from 5500 to 4980 cal yr BP as the transition from the Hypsithermal and into the Neoglacial is made. After a shift to drier conditions, humification enters a more stable period that lasts from 4525 until 3200 cal yr BP. It is during this time that the first possible anthropogenic dust signals occur at ca 4200 cal yr BP. From 3200 cal yr BP to present humification generally shows a long-term decline moving towards wetter conditions. The main exceptions are during the transition from the Neoglacial to Roman Warm Period which is registered as a significantly wetter period and two dry periods recorded 2365 to 2155 cal yr BP and 1275–1105 cal yr BP. In general, the observed changes agree well with regional records of effective humidity and temperature. The high temporal resolution of the Store Mosse record reveals that palaeoclimatic change over the last 8500 years in southern Sweden has had a complex and variable structure.
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| 7. |
- Sonesten, Lars
(author)
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Deformiteter hos oligochaeter i Vänern
- 2014
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Reports (other academic/artistic)abstract
- Bottenlevande slamrörmaskar, oligochaeter, är känsliga miljöindikatorer i alla typerav vatten. I en retrospektiv studie har deformiteter hos oligochaeter från treolika nordliga Vänervikar jämförts under en period med minskad antropogen belastningmed avseende på näringsämnen och olika metaller. Stora mängder av miljöfarligaämnen finns dock lagrade i de sediment som oligochaeterna lever i.Resultaten från undersökningen visar på att de allra grövsta deformitetsformerna,dvs. groteskt förändrade ventrala borst, med tiden generellt sett har minskat i omfattning.Det finns däremot inga tecken på att lättare deformiteter har minskatnämnvärt annat än lokalt. Utöver de skador som noterades på ventrala borst vidtidigare undersökningar så noterades i denna undersökning även att deformiteterhos både dorsala och ventrala borst har tillkommit hos arten Potamothrix hammoniensisi samtliga tre fjärdar. Deformiteterna spänner mellan lättare och mergrava skador, där de lätta dominerar. Liknande skador hos dorsala borst har endastundantagsvis setts i tidigare material från Vänern.Även om förekomsten av de mest grava deformiteterna har minskat, så visar resultatenpå att de lättare skadorna inte har minskat noterbart under den undersöktaperioden annat än på vissa provplatser. Detta skulle kunna tyda på att oligochaeternafortfarande påverkas av upplagrade miljögifter i sedimenten.
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| 8. |
- Arellano, Santiago, 1981
(author)
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Studies of Volcanic Plumes with Remote Spectroscopic Sensing Techniques -DOAS and FTIR measurements on volcanoes of the Network for Observation of Volcanic and Atmospheric Change-
- 2014
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Doctoral thesis (other academic/artistic)abstract
- Volcanism is a rich geodynamical process, closely linked to the origin and ongoing evolution of the lithosphere, atmosphere, hydrosphere and biosphere. Humans have benefited from the resources provided by volcanoes but also been threatened by the dangers of volcanic eruptions, which accurate prediction remains elusive. This is partly due to the inherent complexity of volcanic systems and partly because of the difficulty of conducting key observations to characterize them. In particular, since the segregation and escape of magmatic volatiles are essential mechanisms behind volcanic eruptions, monitoring the intensity and composition of the resulting emissions in the atmosphere is essential to characterize the state of volcanic activity; however, their direct measurement is not always feasible.Remote spectroscopic sensing, whereby gas species can be quantified by their spectral signatures in electromagnetic radiation gathered at a prudent distance from the plume, offers the possibility to conduct reliable and sustainable monitoring of volcanic emissions. To expand the remote sensing capabilities of volcanological observatories the Network for Observation of Volcanic and Atmospheric Change (NOVAC) was established in 2005. The central theme of this thesis is the acquisition, analysis and interpretation of measurements of volcanic gas emissions on volcanoes of NOVAC. Measurements of the mass flow rate of SO2 and the molar ratios of SO2 against BrO and HCl were obtained by scanning-Differential Optical Absorption Spectroscopy (DOAS) of scattered solar ultraviolet radiation and by Fourier-Transform Spectroscopy (FTIR) of direct solar infrared radiation. The uncertainty of the measurements is characterized and methods for combining observations from different sensors implemented. Statistical and physical models of degassing are proposed for selected volcanoes of the network. The resulting time-series of emission on 16 volcanoes is one of the more detailed compilations of volcanic degassing in the last decade, particularly from passive emissions which are difficult to detect from satellite platforms. This work aims at advancing our knowledge of volcanic eruptions for a better mitigation of their risks.
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| 9. |
- Podgrajsek, Eva, et al.
(author)
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Comparison of floating chamber and eddy covariance measurements of lake greenhouse gas fluxes
- 2014
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In: Biogeosciences. - : Copernicus GmbH. - 1726-4170 .- 1726-4189. ; 11, s. 4225-4233
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Journal article (peer-reviewed)abstract
- Fluxes of carbon dioxide (CO2) and methane (CH4) from lakes may have a large impact on the magnitude of the terrestrial carbon sink. Traditionally lake fluxes have been measured using the floating chamber (FC) technique; however, several recent studies use the eddy covariance (EC) method. We present simultaneous flux measurements using both methods at lake Tämnaren in Sweden during field campaigns in 2011 and 2012. Only very few similar studies exist. For CO2 flux, the two methods agree relatively well during some periods, but deviate substantially at other times. The large discrepancies might be caused by heterogeneity of partial pressure of CO2 (pCO2w) in the EC flux footprint. The methods agree better for CH4 fluxes. It is, however, clear that short-term discontinuous FC measurements are likely to miss important high flux events.
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| 10. |
- Steffens, Karin Anna, et al.
(author)
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Modelling pesticide leaching under climate change: parameter vs. climate input uncertainty
- 2014
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In: Hydrology and Earth System Sciences. - : Copernicus GmbH. - 1027-5606 .- 1607-7938. ; 18, s. 479-491
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Journal article (peer-reviewed)abstract
- Assessing climate change impacts on pesticide leaching requires careful consideration of different sources of uncertainty. We investigated the uncertainty related to climate scenario input and its importance relative to parameter uncertainty of the pesticide leaching model. The pesticide fate model MACRO was calibrated against a comprehensive one-year field data set for a well-structured clay soil in southwestern Sweden. We obtained an ensemble of 56 acceptable parameter sets that represented the parameter uncertainty. Nine different climate model projections of the regional climate model RCA3 were available as driven by different combinations of global climate models (GCM), greenhouse gas emission scenarios and initial states of the GCM. The future time series of weather data used to drive the MACRO model were generated by scaling a reference climate data set (1970-1999) for an important agricultural production area in south-western Sweden based on monthly change factors for 2070-2099. 30 yr simulations were performed for different combinations of pesticide properties and application seasons. Our analysis showed that both the magnitude and the direction of predicted change in pesticide leaching from present to future depended strongly on the particular climate scenario. The effect of parameter uncertainty was of major importance for simulating absolute pesticide losses, whereas the climate uncertainty was relatively more important for predictions of changes of pesticide losses from present to future. The climate uncertainty should be accounted for by applying an ensemble of different climate scenarios. The aggregated ensemble prediction based on both acceptable parameterizations and different climate scenarios has the potential to provide robust probabilistic estimates of future pesticide losses.
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| 14. |
- Kreuger, Jenny, et al.
(author)
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Modelling pesticide transport in a shallow groundwater catchment using tritium and helium-3 data
- 2014
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In: Applied Geochemistry. - : Elsevier BV. - 0883-2927. ; 50, s. 231-239
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Journal article (peer-reviewed)abstract
- Using tritium and helium-3 data for calibration, a 2-D transport model was set up to explain the occurrence of bentazone, dichlorprop, glyphosate, isoproturon, MCPA and metamitron in a small groundwater catchment in southern Sweden. The model was parameterised with site-specific degradation and sorption data to enable transport simulations. Local climatological data and a 21-year record of agricultural pesticide use within the study area were used as boundary conditions. Model output was evaluated against a 7-year long pesticide monitoring data-series from two monitoring wells within the study area. The model successfully predicts observed breakthrough of bentazone, dichlorprop, isoproturon and MCPA. However, it fails to simulate observed occurrences of glyphosate and metamitron. Glyphosate and metamitron exhibit relatively high sorption potential, and their occurrence is suggested to be the result of non-equilibrium preferential flow paths which the model cannot reproduce due the conceptualisation of the system as homogenous and isotropic. The results indicate a promising methodological approach applicable to groundwater contamination risk assessment, and demonstrate the potential for transport model calibration by means of tritium and helium-3 data. Main constraints of the study relate to the relatively simple system conceptualisation, indicating a need for further consideration of physical and chemical heterogeneity. (C) 2014 Elsevier Ltd. All rights reserved.
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| 15. |
- Löfgren, Johan, 1983, et al.
(author)
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Sea level measurements using multi-frequency GPS and GLONASS observations
- 2014
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In: Eurasip Journal on Advances in Signal Processing. - : Springer Science and Business Media LLC. - 1687-6172 .- 1687-6180. ; 2014:1
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Journal article (peer-reviewed)abstract
- Global Positioning System (GPS) tide gauges have been realized in different configurations, e.g., with one zenith-looking antenna, using the multipath interference pattern for signal-to-noise ratio (SNR) analysis, or with one zenith- and one nadir-looking antenna, analyzing the difference in phase delay, to estimate the sea level height. In this study, for the first time, we use a true Global Navigation Satellite System (GNSS) tide gauge, installed at the Onsala Space Observatory. This GNSS tide gauge is recording both GPS and Globalnaya Navigatsionnaya Sputnikovaya Sistema (GLONASS) signals and makes it possible to use both the one- and two-antenna analysis approach. Both the SNR analysis and the phase delay analysis were evaluated using dual-frequency GPS and GLONASS signals, i.e., frequencies in the L-band, during a 1-month-long campaign. The GNSS-derived sea level results were compared to independent sea level observations from a co-located pressure tide gauge and show a high correlation for both systems and frequency bands, with correlation coefficients of 0.86 to 0.97. The phase delay results show a better agreement with the tide gauge sea level than the SNR results with root-mean-square differences of 3.5 cm (GPS L1 and L2) and 3.3/3.2 cm (GLONASS L1/L2 bands) compared to 4.0/9.0 cm (GPS L1/L2 ) and 4.7/8.9 cm (GLONASS L1/L2 bands). GPS and GLONASS show similar performance in the comparison, and the results show that for the phase delay analysis, it is possible to use both frequencies, whereas for the SNR analysis, the L2 band should be avoided if other signals are available. Note that standard geodetic receivers using code-based tracking, i.e., tracking the un-encrypted C/A-code on L1 and using the manufacturers’ proprietary tracking method for L2 , were used. Signals with the new C/A-code on L2 , the so-called L2C, were not tracked.Using wind speed as an indicator for sea surface roughness, we find that the SNR analysis performs better in rough sea surface conditions than the phase delay analysis. The SNR analysis is possible even during the highest wind speed observed during this campaign (17.5 m/s), while the phase delay analysis becomes difficult for wind speeds above 6 m/s.
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| 16. |
- Wästfelt, Anders, et al.
(author)
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Local spatial context measurements used to explore the relationship between land cover and land use functions
- 2013
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In: International Journal of Applied Earth Observation and Geoinformation. - : Elsevier BV. - 1569-8432 .- 1872-826X .- 0303-2434. ; 23, s. 234-244
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Journal article (peer-reviewed)abstract
- Research making use of satellite data for land change science has developed in the last decades. However, analysis of land use has not developed with the same speed as development of new satellite sensors and available land cover data. Improvement of land use analysis is possible, but more advanced methods are needed which make it possible to link image data to analysis of land use functions. To make this linking possible, variable which affect farmer's long term decisions must be taken into account in analysis as well as the relative importance of the landscape itself. A GIS-based tool for the measurement of local spatial context in satellite data is presented in this paper and used to explore the relationship between land covers present in satellite data and land use represented in official databases. By the use of the developed tool, a land configuration image (LCI) over the Siljan area in northern Sweden was produced and used for analysis. The results are twofold. First, the produced LCI holds new information about variables that are relevant for the interpretation of land use. Second, the comparison with statistics of agricultural production shows that production in the study area varies depending on the relative land configuration. Villages consisting of relatively large-scale arable fields and less diverse landscape are less diverse in production than villages which consist of smaller-scale and more heterogonous landscapes. The result is especially relevant for land use studies and policymakers working on environmental and agricultural policies. We conclude that local spatial context is an endogenous variable in the relation between landscape configuration and agricultural land use.
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| 17. |
- Earon, Robert, et al.
(author)
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Groundwater Resources Potential in Hard Rock Terrain : A Multivariate Approach
- 2014
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In: Ground Water. - : John Wiley & Sons. - 0017-467X .- 1745-6584.
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Journal article (peer-reviewed)abstract
- Groundwater resources are limited and difficult to predict in crystalline bedrock due to heterogeneity and anisotropy in rock fracture systems. Municipal-level governments often lack the resources for traditional hydrogeological tests when planning for sustainable use of water resources. A new methodology for assessing groundwater resources potential (GRP) based on geological and topographical factors using principal component analysis (PCA) and analysis of variance (ANOVA) was developed and tested. ANOVA results demonstrated statistically significant differences in classed variable groups as well as in classed GRP scores with regard to hydrogeological indicators, such as specific capacity (SC) and transmissivity. Results of PCA were used to govern the weight of the variables used in the prediction maps. GRP scores were able to identify 79% of wells in a verification dataset, which had SC values less than the total dataset median. GRP values showed statistically significant correlations using both parametric (using transformed datasets) and non-parametric methods. The method shows promise for municipal or regional level planning in crystalline terrains with high levels of heterogeneity and anisotropy as a hydrogeologically and statistically based tool to assist in assessing groundwater resources. The methodology is executed in a geographic information systems environment, and uses often readily available data, such as geological maps, feature maps and topography, and thus does not require expensive and time-consuming aquifer tests.
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| 18. |
- Morf, Andrea, 1968, et al.
(author)
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Climate Change Adaptation and Emerging Coastal Conflicts in Southern Sweden: Vellinge Municipality - A Paradigmatic Case Study
- 2012
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In: IGC Cologne 2012, Down To Earth, 32nd International Geographical Congress, 26.-30. August 2012.
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Conference paper (other academic/artistic)abstract
- In Sweden, like in many other European states, there is an increasing need to identify and formulate climate change adaptation strategies at national as well as regional and local level. The Swedish 2007 national report by the Commission on Climate and Vulnerability concluded that Sweden have to make a start in climate adaptation through increased responsibility on behalf of the municipalities in adapting physical planning to the risks of climate change and through the key role of the County Administration Boards in coordinating adaptation efforts at the regional level. Since then, municipalities vulnerable to climate change impacts has started to identify and propose adaptation measures (under the coordination and support by the County Administration Boards), and a few municipalities have even started the process of integration adaptation measures into their physical planning. However, the integration of adaptation measures into comprehensive plans is a new and complex task, causing 'new' conflicts of interests to emerge. For example: · Between the interests to retreat from, defend against or adapt to future climate risks · Between present and future nature- and human values · Between existing national and regional regulations of local physical planning and the need for local flexibility in physical planning in responding to uncertain, future climate change risks · Between national, regional and local interests in relation to climate change adaptation · Between different social groups (for example between temporary and permanent residents) Through a case study of the municipality of Vellinge, located in the southwestern part of Sweden with a population of approximately 30 000, we analyze the potential consequences (in terms of emergence of new conflicts of interests) of the detailed, physical adaptation measures that have been put forward in the draft municipality comprehensive plan of 2010. Furthermore, we discuss potential strategies to mitigate such emerging conflicts.
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| 19. |
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| 20. |
- Kirchner, N., et al.
(author)
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Capabilities and limitations of numerical ice sheet models : a discussion for Earth-scientists and modelers
- 2011
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In: Quaternary Science Reviews. - : Elsevier. - 0277-3791 .- 1873-457X. ; 30:25-26, s. 3691-3704
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Journal article (peer-reviewed)abstract
- The simulation of dynamically coupled ice sheet, ice stream, and ice shelf-systems poses a challenge to most numerical ice sheet models. Here we review present ice sheet model limitations targeting a broader audience within Earth Sciences, also those with no specific background in numerical modeling, in order to facilitate cross-disciplinary communication between especially paleoglaciologists, marine and terrestrial geologists, and numerical modelers. The ‘zero order’(Shallow Ice Approximation, SIA)-,‘higher order’-, and‘full Stokes’ice sheet models are described conceptually and complemented by an outline of their derivations. We demonstrate that higher order models are required to simulate coupled ice sheetice shelf and ice sheet-ice stream systems, in particular if the results are aimed to complement spatial ice flow reconstructions based on higher resolution geological and geophysical data. The zero order SIA model limitations in capturing ice stream behavior are here illustrated by conceptual simulations of a glaciation on Svalbard. The limitations are obvious from the equations comprising a zero order model. However, under certain circumstances, simulation results may falsely give the impression that ice streams indeed are simulated with a zero order SIA model.
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| 21. |
- Vikström, Hanna, 1985-, et al.
(author)
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Lithium availability and future production outlooks
- 2013
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In: Applied Energy. - : Elsevier BV. - 0306-2619 .- 1872-9118. ; 110:10, s. 252-266
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Journal article (peer-reviewed)abstract
- Lithium is a highly interesting metal, in part due to the increasing interest in lithium-ion batteries. Several recent studies have used different methods to estimate whether the lithium production can meet an increasing demand, especially from the transport sector, where lithium-ion batteries are the most likely technology for electric cars. The reserve and resource estimates of lithium vary greatly between different studies and the question whether the annual production rates of lithium can meet a growing demand is seldom adequately explained. This study presents a review and compilation of recent estimates of quantities of lithium available for exploitation and discusses the uncertainty and differences between these estimates. Also, mathematical curve fitting models are used to estimate possible future annual production rates. This estimation of possible production rates are compared to a potential increased demand of lithium if the International Energy Agency’s Blue Map Scenarios are fulfilled regarding electrification of the car fleet. We find that the availability of lithium could in fact be a problem for fulfilling this scenario if lithium-ion batteries are to be used. This indicates that other battery technologies might have to be implemented for enabling an electrification of road transports.
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| 22. |
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| 23. |
- Blennow, Kristina, et al.
(author)
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Implementing storm damage in a dynamic vegetation model for regional applications in Sweden
- 2012
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In: Ecological Modelling. - : Elsevier BV. - 0304-3800 .- 1872-7026. ; 247, s. 71-82
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Journal article (peer-reviewed)abstract
- Wind is the dominant agent of damage in forests in Western Europe. Traditional wind-damage models calculate a probability for damage or a critical wind speed at which damage occurs. However, in a dynamic vegetation model actual damage to stands and individual trees is needed to get a dynamical progression of the vegetation. We present a prototype for a new approach to modelling forest wind damage at the regional scale, which we incorporate within a dynamic vegetation model. The approach is based on knowledge from both empirical and mechanical models and calculates the damaged fraction of a cohort based on wind load and a sensitivity that depends on the current physical state and history of the cohort in relation to the ecosystem. The modelling concept has been developed, calibrated and evaluated for Swedish conditions but can be applicable to other similar areas with minor modification. Because of the stochastic nature of local wind load and the difficulty of describing the stand-level exposure, the ability to explain observed damage at stand level was low. Regional level variation in damage, which more depends on the wind load, was however explained reasonably well (R-2 = 0.43). We suggest that this is a useful concept for evaluating alternatives of forest management under different climate scenarios in the process of adaptation to future storm-damage risks. (C) 2012 Elsevier B.V. All rights reserved.
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| 24. |
- Comstedt, Daniel, et al.
(author)
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Autotrophic and heterotrophic soil respiration in a Norway spruce forest : estimating the root decomposition and soil moisture effects in a trenching experiment
- 2011
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In: Biogeochemistry. - : Springer. - 0168-2563 .- 1573-515X. ; 104:1-3, s. 121-132
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Journal article (peer-reviewed)abstract
- The two components of soil respiration, autotrophic respiration (from roots, mycorrhizal hyphae and associated microbes) and heterotrophic respiration (from decomposers), was separated in a root trenching experiment in a Norway spruce forest. In June 2003, cylinders (29.7 cm diameter) were inserted to 50 cm soil depth and respiration was measured both outside (control) and inside the trenched areas. The potential problems associated with the trenching treatment, increased decomposition of roots and ectomycorrhizal mycelia and changed soil moisture conditions, were handled by empirical modelling. The model was calibrated with respiration, moisture and temperature data of 2004 from the trenched plots as a training set. We estimate that over the first 5 months after the trenching, 45% of respiration from the trenched plots was an artefact of the treatment. Of this, 29% was a water difference effect and 16% resulted from root and mycelia decomposition. Autotrophic and heterotrophic respiration contributed to about 50% each of total soil respiration in the control plots averaged over the two growing seasons. We show that the potential problems with the trenching, decomposing roots and mycelia and soil moisture effects, can be handled by a modelling approach, which is an alternative to the sequential root harvesting technique.
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| 25. |
- Karlsson, Emma, 1980-
(author)
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Organic geochemical investigation of sources, transport and fate of terrestrial organic matter in the southeast Laptev Sea
- 2012
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Licentiate thesis (other academic/artistic)abstract
- Permafrost carbon stores have been suggested to react to warming trends with increased terrestrial loading to its coastal waters. Presently, the warming has been seen to be especially high in the East Siberian Arctic and the fate of the major release of terrestrial matter to these coasts is yet to be detailed.Our work is focused on the East Siberian Shelf (ESS) – which is the largest continental shelf in the world. It receives substantial inputs of terrestrial organic matter both from the large Russian rivers and from eroding coastlines. The largest of its rivers, the Lena, discharges in Buor-Khaya Bay, which is also a hot spot for coastal erosion.Previous studies of molecular and δ¹3C and Δ¹⁴C composition of terrestrial organic matter received by Arctic coastal waters have suggested a different propensity of different terrestrial source materials towards bacterial degradation. This detailed isotopic and molecular marker survey which is the basis for this thesis reveals clearly distinguished source patterns both between surface water (POC) and sea floor (SOC) as well as with distance away from the sources. The heavy terrestrial dominance over marine/planktonic sources are clearly detected in gradients of high POC and SOC levels, as well as depleted δ13C -OC and high HMW/LMW n-alkane ratios. Furthermore, data suggests that terr-OC was substantially older yet less degraded in the surface sediment than in the surface waters. This unusual vertical degradation trend was only recently found also for the coastal and central East Siberian Sea. It seems that the riverine terr-OC component comprising mainly annual thaw layer surface soil dominates the buoyant surface water POC and is readily degraded. This is in contrast to the coastline-erosion terr-OC which is associated with minerals and therefore ballasted to the sediments where it makes up the key OC component and seems relatively protected from degradation.The study area of this work is a region with strong terrestrial influence hosting many of the important carbon cycling processes, and data reveal two important OC contributors of different origin, mineral associated coastal erosion matter and riverine borne surface soil matter. These two components may well represent different propensities to contribute to a positive feedback to climate warming by converting OC from coastal and inland permafrost into CO₂.
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