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  • 1. Aamaas, Borgar
    et al.
    Boggild, Carl Egede
    Stordal, Frode
    Berntsen, Terje
    Holmen, Kim
    Ström, Johan
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Elemental carbon deposition to Svalbard snow from Norwegian settlements and long-range transport2011In: Tellus. Series B, Chemical and physical meteorology, ISSN 0280-6509, E-ISSN 1600-0889, Vol. 63, no 3, p. 340-351Article in journal (Refereed)
    Abstract [en]

    The impact on snow pack albedo from local elemental carbon (EC) sources in Svalbard has been investigated for the winter of 2008. Highly elevated EC concentrations in the snow are observed around the settlements of Longyearbyen and Svea (locally > 1000 ng g(-1), about 200 times over the background level), while EC concentrations similar to the background level are seen around Ny-Alesund. Near Longyearbyen and Svea, darkened snow influenced by wind transported coal dust from open coal stockpiles is clearly visible from satellite images and by eye at the ground. As a first estimate, the reduction in snow albedo caused by local EC pollution from the Norwegian settlements has been compared to the estimated reduction caused by long-range transported EC for entire Svalbard. The effect of local EC from Longyearbyen, Svea and all Norwegian settlements are estimated to 2.1%, 7.9% and 10% of the total impact of EC, respectively. The EC particles tend to stay on the surface during melting, and elevated EC concentrations due to the spring melt was observed. This accumulation of EC enhances the positive albedo feedbacks. The EC concentrations were observed to be larger in metamorphosed snow than in fresh snow, and especially around ice lenses.

  • 2. Abbasi, Alireza
    et al.
    Geranmayeh, Shokoofeh
    Skripkin, Mikhail Y.
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK).
    Eriksson, Lars
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK).
    Potassium ion-mediated non-covalent bonded coordination polymers2012In: Dalton Transactions, ISSN 1477-9226, E-ISSN 1477-9234, Vol. 41, no 3, p. 850-859Article in journal (Refereed)
    Abstract [en]

    Crystal structures and vibrational spectra of three related network-forming coordination complexes have been studied. Two novel thermodynamically stable pseudo-polymorphic solvated rhodium chloro compounds, [cis-RhCl4(DMSO-kappa S)(2)K](n), 1, and [cis-RhCl4(DMSO-kappa S)(2)K center dot 3H(2)O](n), 2, and one metastable compound [trans-RhCl4(DMSO-kappa S)(2)K center dot 0.25H(2)O](n), 3, crystallize at ambient temperature in the orthorhombic space group P2(1)2(1)2(1) for 1, and the monoclinic space groups P2(1)/n and P2(1)/c for 2 and 3, respectively. All three structures contain [RhCl4(DMSO-kappa S)(2)]-complexes in which the rhodium(III) ions bind to two dimethyl sulfoxide (DMSO) sulfur atoms and four chloride ions in distorted octahedral coordination geometries. The complexes are connected in networks via potassium ions interacting with the Cl- and the DMSO oxygen atoms. As the sum of Shannon ionic radii of K+ and Cl- exceeds the K-Cl distances in compounds under study, these compounds can be described as Rh-Cl-K coordination polymers with non-covalent bonding, which is not common in these systems, forming 1- and 2-D networks for 1/2 and 3, respectively. The 2-D network with nano-layered sheets for compound 3 was also confirmed by TEM images. Further evaluation of the bonding in the cis- and trans-[RhCl4(DMSO-kappa S)(2)](-) entities was obtained by recording Raman and FT-IR absorption spectra and assigning the vibrational frequencies with the support of force-field calculations. The force field study of complexes reveals the strong domination of trans-effect (DMSO-kappa S > Cl) over the effect of non-covalent bonding in coordination polymeric structures. The comparison of calculated RhCl, RhS and SO stretching force constants showed evidence of K+-ligand interactions whereas direct experimental evidences of K+-Cl- interaction were not obtained because of strong overlap of the corresponding spectral region with that where lattice modes and Rh-ligand bendings appear.

  • 3.
    Abbasi, Saeed
    et al.
    KTH Royal Inst Technol, Dept Machine Design, Stockholm, Sweden.
    Jansson, Anders
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Sellgren, Ulf
    KTH Royal Inst Technol, Dept Machine Design, Stockholm, Sweden.
    Olofsson, Ulf
    KTH Royal Inst Technol, Dept Machine Design, Stockholm, Sweden.
    Particle Emissions From Rail Traffic: A Literature Review2013In: Critical reviews in environmental science and technology, ISSN 1064-3389, E-ISSN 1547-6537, Vol. 43, no 23, p. 2511-2544Article, review/survey (Refereed)
    Abstract [en]

    Particle emissions are a drawback of rail transport. This work is a comprehensive presentation of recent research into particle emissions from rail vehicles. Both exhaust and nonexhaust particle emissions are considered when examining particle characteristics such as PM10, and PM2.5 concentration levels, size, morphology, composition, and adverse health effects, current legislation, and available and proposed solutions for reducing such emissions. High concentration levels in enclosed rail traffic environments are reported and some toxic effects of the particles. The authors find that only a few limited studies have examined the adverse health effects of nonexhaust particle emissions and that no relevant legislation exists. Thus further research in this area is warranted.

  • 4. Abunge, Caroline
    et al.
    Coulthard, Sarah
    Daw, Tim M.
    Stockholm University, Faculty of Science, Stockholm Resilience Centre.
    Connecting Marine Ecosystem Services to Human Well-being: Insights from Participatory Well-being Assessment in Kenya2013In: Ambio, ISSN 0044-7447, E-ISSN 1654-7209, Vol. 42, no 8, p. 1010-1021Article in journal (Refereed)
    Abstract [en]

    The linkage between ecosystems and human well-being is a focus of the conceptualization of ecosystem services as promoted by the Millennium Ecosystem Assessment. However, the actual nature of connections between ecosystems and the well-being of individuals remains complex and poorly understood. We conducted a series of qualitative focus groups with five different stakeholder groups connected to a small-scale Kenyan coastal fishery to understand (1) how well-being is understood within the community, and what is important for well-being, (2) how people's well-being has been affected by changes over the recent past, and (3) people's hopes and aspirations for their future fishery. Our results show that people conceive well-being in a diversity of ways, but that these can clearly map onto the MA framework. In particular, our research unpacks the freedoms and choices element of the framework and argues for greater recognition of these aspects of well-being in fisheries management in Kenya through, for example, more participatory governance processes.

  • 5.
    Acosta Navarro, Juan Camilo
    Stockholm University, Faculty of Science, Department of Environmental Science and Analytical Chemistry.
    Anthropogenic influence on climate through changes in aerosol emissions from air pollution and land use change2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Particulate matter suspended in air (i.e. aerosol particles) exerts a substantial influence on the climate of our planet and is responsible for causing severe public health problems in many regions across the globe. Human activities have altered the natural and anthropogenic emissions of aerosol particles through direct emissions or indirectly by modifying natural sources. The climate effects of the latter have been largely overlooked. Humans have dramatically altered the land surface of the planet causing changes in natural aerosol emissions from vegetated areas. Regulation on anthropogenic and natural aerosol emissions have the potential to affect the climate on regional to global scales. Furthermore, the regional climate effects of aerosol particles could potentially be very different than the ones caused by other climate forcers (e.g. well mixed greenhouse gases). The main objective of this work was to investigate the climatic effects of land use and air pollution via aerosol changes.

    Using numerical model simulations it was found that land use changes in the past millennium have likely caused a positive radiative forcing via aerosol climate interactions. The forcing is an order of magnitude smaller and has an opposite sign than the radiative forcing caused by direct aerosol emissions changes from other human activities. The results also indicate that future reductions of fossil fuel aerosols via air quality regulations may lead to an additional warming of the planet by mid-21st century and could also cause an important Arctic amplification of the warming. In addition, the mean position of the intertropical convergence zone and the Asian monsoon appear to be sensitive to aerosol emission reductions from air quality regulations. For these reasons, climate mitigation policies should take into consideration aerosol air pollution, which has not received sufficient attention in the past.

  • 6.
    Acosta Navarro, Juan Camilo
    Stockholm University, Faculty of Science, Department of Environmental Science and Analytical Chemistry.
    Historical anthropogenic radiative forcing of changes in biogenic secondary organic aerosol2015Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Human activities have lead to changes in the energy balance of the Earth and the global climate. Changes in atmospheric aerosols are the second largest contributor to climate change after greenhouse gases since 1750 A.D. Land-use practices and other environmental drivers have caused changes in the emission of biogenic volatile organic compounds (BVOCs) and secondary organic aerosol (SOA) well before 1750 A.D, possibly causing climate effects through aerosol-radiation and aerosol-cloud interactions. Two numerical emission models LPJ-GUESS and MEGAN were used to quantify the changes in aerosol forming BVOC emissions in the past millennium. A chemical transport model of the atmosphere (GEOS-Chem-TOMAS) was driven with those BVOC emissions to quantify the effects on radiation caused by millennial changes in SOA.

    The specific objectives of this licentiate thesis are: 1) to understand what drove the changes in aerosol-forming BVOC emissions (i.e. isoprene, monoterpenes and sesquiterpenes) and to quantify these changes; 2) to calculate for the first time the combined historical aerosol direct and aerosol-cloud albedo effects on radiation from changing BVOC emissions through SOA formation; 3) to investigate how important the biological climate feedback associated to BVOC emissions and SOA formation is from a global climate perspective.

    We find that global isoprene emissions decreased after 1800 A.D. by about 12% - 15%. This decrease was dominated by losses of natural vegetation, whereas monoterpene and sesquiterpene emissions increased by about 2% - 10%, driven mostly by rising surface air temperatures. From 1000 A.D. to 1800 A.D, isoprene, monoterpene and sesquiterpene emissions decline by 3% - 8% driven by both, natural vegetation losses, and the moderate global cooling between the medieval climate anomaly and the little ice age. The millennial reduction in BVOC emissions lead to a 0.5% to 2% reduction in climatically relevant aerosol particles (> 80 nm) and cause a direct radiative forcing between +0.02 W/m² and +0.07 W/m², and an indirect radiative forcing between -0.02 W/m² and +0.02 W/m². The suggested biological climate feedback seems to be too small to have observable consequences on the global climate in the recent past.

  • 7.
    Adolfsson-Erici, Margaretha
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Fish bile in environmental analysis2005Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    This work explores the usefulness of fish bile analysis in combination with biomarkers for identifying and evaluating new environmental contaminants in the aquatic environment. It illustrates how bile analysis can be used together with biomarkers to assess the causes of estrogenic effects, to identify chemicals in the aquatic environment that are taken up by fish, and to monitor environmental exposure.

    In a first application, fish exposed to sewage treatment plant effluent were studied. Elevated levels of vitellogenin in the exposed fish demonstrated that estrogenic effects occurred. Several estrogen disrupting substances were identified in the fish bile, and analysis of water samples confirmed that these substances were present in the effluent. The synthetic estrogen 17a-ethinylestradiol, which is known to be present in sewage treatment plant effluent, was shown for the first time to be taken up by fish. Considering the reported potencies of the detected substances, it was concluded that 17a-ethinylestradiol was the major contributor to the estrogenic effects.

    Chemical analysis of bile was used to identify rubber additives that were released from tires immersed in water. The bile of rainbow trout held in the water contained high levels of metabolites of PAHs and aromatic nitrogen compounds. Several biomarkers were also measured in the exposed fish, and EROD induction and oxidative stress were observed. Based on the bile analysis observations together with knowledge of toxicological mechanisms, it was postulated that the EROD induction was due to the PAHs, while aromatic nitrogen compounds caused the oxidative stress.

    Resin acids in fish bile proved to be a good indicator of exposure in a chronic long-term study of rainbow trout exposed to effluent from a total chlorine free (TCF) pulp mill. Elevated levels of GST (gluthatione-S-transferase) and GR (gluthatione reductase) activity, and the presence of DNA adducts after a two month recovery period, indicated that compounds in the pulp mill effluents have persistent effects. In addition to characterising the exposure of the fish to the effluent, the analysis of the resin acids in the bile provided evidence of accidents in the pulp mill that the existing process monitoring system had not detected.

    Resin acids in bile were also found to be a valuable indicator of exposure to pulp mill effluents for eelpout living in the Baltic Sea. A correlation between resin acid levels in bile and skewed sex ratios provided an important link in the chain of evidence that substances in the pulp mill effluents cause male bias of the eelpout embryos.

    A particularly good example of the potential of bile analysis was the identification of a previously unknown environmental contaminant. A large peak was observed in the bile extracts of fish that had been exposed to sewage treatment plant effluent. This peak was identified as triclosan, which demonstrated its presence in sewage treatment plant effluent. Other work went on to show that it is a common contaminant of the aquatic environment. The ability of fish to concentrate contaminant metabolites in bile to levels very much higher than in the environment, and the comparatively low levels of analytic interferences, make bile a particularly attractive matrix to search for new, unknown organic pollutants

  • 8.
    Adolfsson-Erici, Margaretha
    et al.
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Åkerman, Gun
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Jahnke, Annika
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Mayer, Philipp
    McLachlan, Michael S.
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    A flow-through passive dosing system for continuously supplying aqueous solutions of hydrophobic chemicals to bioconcentration and aquatic toxicity tests2012In: Chemosphere, ISSN 0045-6535, E-ISSN 1879-1298, Vol. 86, no 6, p. 593-599Article in journal (Refereed)
    Abstract [en]

    A continuous supply of water with defined stable concentrations of hydrophobic chemicals is a requirement in a range of laboratory tests such as the OECD 305 protocol for determining the bioconcentration factor in fish. Satisfying this requirement continues to be a challenge, particularly for hydrophobic chemicals. Here we present a novel solution based on equilibrium passive dosing. It employs a commercially available unit consisting of similar to 16000 polydimethylsiloxane (PDMS) tubes connected to two manifolds. The chemicals are loaded into the unit by repeatedly perfusing it with a methanol solution of the substances that is progressively diluted with water. Thereafter the unit is perfused with water and the chemicals partition from the unit into the water. The system was tested with nine chemicals with logK(ow) ranging from 4.1 to 6.3. The aqueous concentrations generated were shown to be largely independent of the water flow rate, and the unit to unit reproducibility was within a factor of similar to 2. In continuous flow experiments the aqueous concentrations of most of the study chemicals remained constant over 8 d. A model was assembled that allows prediction of the operating characteristics of the system from the logKow or PDMS/water partition coefficient of the chemical. The system is a simple, safe, predictable and flexible tool that generates stable aqueous concentrations of hydrophobic chemicals.

  • 9.
    Adolfsson-Erici, Margaretha
    et al.
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Åkerman, Gun
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    McLachlan, Michael S.
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Internal Benchmarking Improves Precision and Reduces Animal Requirements for Determination of Fish Bioconcentration Factors2012In: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 46, no 15, p. 8205-8211Article in journal (Refereed)
    Abstract [en]

    The enactment of new chemical regulations has generated a large need for the measurement of the fish bioconcentration factor (BCF). Past experience shows that the BCF determination lacks precision, requires large numbers of fish, and is costly. A new protocol was tested that shortens the experiment from up to 12 weeks for existing protocols to 2 weeks and reduces the number of fish by a factor of 5, while introducing internal benchmarking for the BCF determination. Rainbow trout were simultaneously exposed to 11 chemicals. The BCFs were quantified using one of the test chemicals, musk xylene, as a benchmark. These were compared with BCFs measured in a parallel experiment based on the OECD 305 guideline. The agreement was <20% for five chemicals and between 20%-25% for two further, while two chemicals lay outside the BCF operating window of the experiment and one was lost due to analytical difficulties. This agreement is better than that observed in a BCF Gold Standard Database. Internal benchmarking allows the improvement of the precision of BCF determination in parallel to large reduction in costs and fish requirements.

  • 10.
    Adolfsson-Erici, Margaretha
    et al.
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Åkerman, Gun
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    McLachlan, Michael S.
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    In-vivo passive sampling to measure elimination kinetics in bioaccumulation tests2012In: Chemosphere, ISSN 0045-6535, E-ISSN 1879-1298, Vol. 88, no 1, p. 62-68Article in journal (Refereed)
    Abstract [en]

    The application of in-tissue passive sampling to quantify chemical kinetics in fish bioconcentration experiments was investigated. A passive sampler consisting of an acupuncture needle covered with a PDMS tube was developed together with a method for its deployment in rainbow trout. The time to steady state for chemical uptake into the passive sampler was >1 d, so it was employed as a kinetically limited sampler with a deployment time of 2 h. The passive sampler was employed in parallel with the established whole tissue extraction method to study the elimination kinetics of 10 diverse chemicals in rainbow trout. 4-n-nonylphenol and 2,4,6-tri-tert-butylphenol were close to or below the limit of quantification in the sampler. For chlorpyrifos, musk xylene, hexachlorobenzene, 2,5-dichlorobiphenyl and p,p'-DDT. the elimination rate constants determined with the passive sampler method and the established method agreed within 18%. Poorer agreement (35%) was observed for 2,3,4-trichloroanisole and p-diisopropylbenzene because fewer data were obtained with the passive sampling method due to its lower sensitivity. The work shows that in-tissue passive sampling can be employed to measure contaminant elimination kinetics in fish. This opens up the possibility of studying contaminant kinetics in individual fish, thereby reducing the fish requirements and analytical costs for the determination of bioconcentration factors.

  • 11.
    Adolfsson-Erici, Margaretha
    et al.
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Åkerman, Gun
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    McLachlan, Michael S.
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Measuring bioconcentration factors in fish using exposure to multiple chemicals and internal benchmarking to correct for growth dilution2012In: Environmental Toxicology and Chemistry, ISSN 0730-7268, E-ISSN 1552-8618, Vol. 31, no 8, p. 1853-1860Article in journal (Refereed)
    Abstract [en]

    Modern chemical legislation requires measuring the bioconcentration factor (BCF) of large numbers of chemicals in fish. The BCF must be corrected for growth dilution, because fish growth rates vary between laboratories. Two hypotheses were tested: (1) that BCFs of multiple chemicals can be measured simultaneously in one experiment, and (2) that internal benchmarking using a conservative test substance in the chemical mixture can be used to correct for growth dilution. Bioconcentration experiments were conducted following major elements of the OECD 305 guideline. Fish were simultaneously exposed to 11 chemicals selected to cover a range of BCFs and susceptibility to biotransformation. A method was developed to calculate the growth-corrected elimination rate constant from the concentration ratio of the analyte and a benchmarking chemical for which growth dilution dominated other elimination mechanisms. This method was applied to the experimental data using hexachlorobenzene as the benchmarking chemical. The growth dilution correction lowered the apparent elimination rate constants by between 5% and a factor of four for eight chemicals, while for two chemicals the growth-corrected elimination rate constant was not significantly different from zero. The benchmarking method reduced the uncertainty in the elimination rate constant compared to the existing method for growth dilution correction. The BCFs from exposing fish to 10 chemicals at once were consistent with BCF values from single-chemical exposures from the literature, supporting hypothesis 1. Environ. Toxicol. Chem. 2012; 31: 18531860. (c) 2012 SETAC

  • 12.
    Aeppli, Christoph
    et al.
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Bastviken, David
    Andersson, Per
    Gustafsson, Örjan
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Chlorine Isotope Effects and Composition of Naturally Produced Organochlorines from Chloroperoxidases, Flavin-Dependent Halogenases, and in Forest Soil2013In: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 47, no 13, p. 6864-6871Article in journal (Refereed)
    Abstract [en]

    The use of stable chlorine isotopic signatures (delta Cl-37) of organochlorine compounds has been suggested as a tool to determine both their origins and transformations in the environment. Here we investigated the delta Cl-37 fractionation of two important pathways for enzymatic natural halogenation: chlorination by chloroperoxidase (CPO) and flavin-dependent halogenases (FDH). Phenolic products of CPO were highly Cl-37 depleted (delta Cl-37 = -12.6 +/- 0.9 parts per thousand); significantly more depleted than all known industrially produced organochlorine compounds (delta Cl-37 = -7 to +6 parts per thousand). In contrast, four FDH products did not exhibit any observable isotopic shifts (delta Cl-37 = -0.3 +/- 0.6 parts per thousand). We attributed the different isotopic effect to the distinctly different chlorination mechanisms employed by the two enzymes. Furthermore, the delta Cl-37 in bulk organochlorines extracted from boreal forest soils were only slightly depleted in Cl-37 relative to inorganic Cl. In contrast to previous suggestions that CPO plays a key role in production of soil organochlorines, this observation points to the additional involvement of either other chlorination pathways, or that dechlorination of naturally produced organochlorines can neutralize delta Cl-37 shifts caused by CPO chlorination. Overall, this study demonstrates that chlorine isotopic signatures are highly useful to understand sources and cycling of organochlorines in nature. Furthermore, this study presents delta Cl-37 values of FDH products as well of bulk organochlorines extracted from pristine forest soil for the first time.

  • 13.
    Aeppli, Christoph
    et al.
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Tysklind, Mats
    Holmstrand, Henry
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Gustafsson, Örjan
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Use of Cl and C Isotopic Fractionation to Identify Degradation and Sources of Polychlorinated Phenols: Mechanistic Study and Field Application2013In: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 47, no 2, p. 790-797Article in journal (Refereed)
    Abstract [en]

    The widespread use of chlorinated phenols (CPs) as a wood preservative has led to numerous contaminated sawmill sites. However, it remains challenging to assess the extent of in situ degradation of CPs. We evaluated the use of compound-specific chlorine and carbon isotope analysis (Cl- and C-CSLA) to assess CP biotransformation. In a laboratory system, we measured isotopic fractionation during oxidative 2,4,6-trichlorophenol dechlorination by representative soil enzymes (C. fumago chloroperoxidase, horseradish peroxidase, and laccase from T. versicolor). Using a mathematical model, the validity of the Rayleigh approach to evaluate apparent kinetic isotope effects (AKIE) was confirmed. A small but significant Cl-AKIE of 1.0022 +/- 0.0006 was observed for all three enzymes, consistent with a reaction pathway via a cationic radical species. For carbon, a slight inverse isotope effect was observed (C-AKIE = 0.9945 +/- 0.0019). This fractionation behavior is clearly distinguishable from reported reductive dechlorination mechanisms. Based on these results we then assessed degradation and apportioned different types of technical CP mixtures used at two former sawmill sites. To our knowledge, this is the first study that makes use of two-element CSIA to study sources and transformation of CPs in the environment.

  • 14. Agerstrand, M
    et al.
    Wester, M
    Rudén, C
    The Swedish Environmental Classification and Information System for Pharmaceuticals--an empirical investigation of the motivations, intentions and expectations underlying its development and implementation.2009In: Environment International, ISSN 0160-4120, E-ISSN 1873-6750, Vol. 35, no 5, p. 778-86Article in journal (Refereed)
    Abstract [en]

    In 2005 the Swedish Association of the Pharmaceutical Industry (LIF) initiated a national environmental classification and information system for pharmaceuticals. This investigation reports the results from a survey, conducted among the persons involved in the start-up process. The aim of this study is to generate knowledge contributing to the clarification of the motivations, expectations, and intentions underlying the development and implementation of the system. The decision to implement a classification and information system for pharmaceuticals was the result of a combination of several driving forces, mainly political pressure and a possibility to increase the industries' goodwill, while at the same time keeping the process under the industries' control. The expected possible effects of the system, other than increased goodwill, are according to this survey assumed to be low. The system offers little guidance for end-users in the substitution of one pharmaceutical for another. One possible reason for this could be that LIF needs to observe the interests of all its members' and should not affect competition. The affiliation of the involved actors correlates to how these actors view and value the system, but this has not hampered the collaborative process to develop and implement it.

  • 15. Agerstrand, Marlene
    et al.
    Rudén, Christina
    Evaluation of the accuracy and consistency of the Swedish environmental classification and information system for pharmaceuticals.2010In: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 408, no 11, p. 2327-39Article in journal (Refereed)
    Abstract [en]

    The Swedish environmental and classification system for pharmaceuticals is a voluntary, industry-owned system with the purpose to provide environmental information about active pharmaceutical ingredients in the Swedish market. In this paper we report the results from a detailed evaluation of the accuracy and consistency of the risk assessments conducted within this system. The evaluation focused on the following three aspects: 1) comparison of the companies' risk assessments with the classification system's own guidance document, 2) how the risk assessments are affected if additional effect data is used, and 3) the consistency of different risk assessments for the same pharmaceutical substance. The analyses show that the system's guidance gives no criteria for when to consider a study "long-term" or "short-term", and that this confusion affected the outcome of the risk assessments in some cases. Furthermore, when the system's guidance document is followed and the risk assessment was supplemented with effect data from the open scientific literature, then the risk classification for a substantial number of the evaluated substances was altered. Our analyses also revealed that in some cases risk assessors disagree on the outcome of the assessment for the same active pharmaceutical ingredient. Finally we list some recommendations to improve the classification system. The recommendations include clarifying concepts and instructions in the guidance document, introduction of a standardized way of reporting data to the website, and promotion of use of non-standard test data when considered the most relevant.

  • 16.
    Aggemyr, Elsa
    et al.
    Stockholm University, Faculty of Science, Department of Physical Geography and Quaternary Geology.
    Cousins, Sara A. O.
    Stockholm University, Faculty of Science, Department of Physical Geography and Quaternary Geology.
    Landscape structure and land use history influence changes in island plant composition after 100 years2012In: Journal of Biogeography, ISSN 0305-0270, E-ISSN 1365-2699, Vol. 39, no 9, p. 1645-1656Article in journal (Refereed)
    Abstract [en]

    Aim We investigated how current and historical land use and landscape structure affect species richness and the processes of extinction, immigration and species turnover. Location The northern part of the Stockholm archipelago, Baltic Sea, Sweden. We resurveyed 27 islands ranging from 0.3 to 33 ha in area. Methods We compared current plant survey data, cadastral maps and aerial photographs with records obtained from a survey in 1908, using databases and a digital elevation model to examine changes in plant community dynamics in space and time. We examined the effects of local and landscape structure and land use changes on plant species dynamics by using stepwise regression in relation to eight local and three landscape variables. The eight local variables were area, relative age, shape, soil heterogeneity, bedrock ratio, number of houses, forest cover change, and grazing 100 years ago. The three landscape variables were distance to mainland, distance to closest island with a farm 100 years ago, and structural connectivity. Hanskis connectivity measure was modified to incorporate both connectivity and fragmentation. Results The investigated islands have undergone drastic changes, with increasing forest cover, habitation, and abandonment of grassland management. Although the total species richness increased by 31% and mean island area by 23%, we found no significant increase in species richness per unit area. Local variables explain past species richness (100 years ago), whereas both local and landscape variables explain current species richness, extinctions, immigrations and species turnover. Grazing that occurred 100 years ago still influences species richness, even though grazing management was abandoned several decades ago. The evidence clearly shows an increase in nitrophilous plant species, particularly among immigrant species. Main conclusions This study highlights the importance of including land use history when interpreting current patterns of species richness. Furthermore, local environment and landscape patterns affect important ecological processes such as immigration, extinction and species turnover, and hence should be included when assessing the impact of habitat fragmentation and land use change. We suggest that our modified structural connectivity measure can be applied to other types of landscapes to investigate the effects of fragmentation and habitat loss.

  • 17. Ahlvik, P
    et al.
    Karlsson, Hans
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Westerholm, Roger
    Stockholm University, Faculty of Science, Department of Analytical Chemistry.
    Åsman, P
    Exhaust emissions from flexi-fuel light-duty passenger cars fuelled by petrol (E5) and bioethanol (E70, E85) tested at ambient temperatures of +22°C and -7°C: Part 1:Regulated and particulate emissions.2008In: Proceedings of the17:th International Symposium on Alcohol Fuels, 2008Conference paper (Other academic)
  • 18.
    Ahmadi, Hamid
    et al.
    Stockholm University, Faculty of Science, Department of Environmental Science and Analytical Chemistry.
    Bolinius, Dämien Johann
    Stockholm University, Faculty of Science, Department of Environmental Science and Analytical Chemistry.
    Jahnke, Annika
    MacLeod, Matthew
    Stockholm University, Faculty of Science, Department of Environmental Science and Analytical Chemistry.
    Mass transfer of hydrophobic organic chemicals between siliconesheets and through plant leaves and low-density polyethylene2016In: Chemosphere, ISSN 0045-6535, E-ISSN 1879-1298, Vol. 164, p. 683-690Article in journal (Refereed)
    Abstract [en]

    Plant leaves play an important role in the fate of hydrophobic organic contaminants (HOCs) in theenvironment. Yet much remains unknown about the permeability of leaves by HOCs. In this pilot studywe measured (i) the kinetics of mass transfer of three polycyclic aromatic hydrocarbons (PAHs) and sixpolychlorinated biphenyls between a spiked and an unspiked sheet of polydimethylsiloxane (PDMS) indirect contact with each other for 24 h and (ii) kinetics of mass transfer of two PAHs through leaves andlow-density polyethylene (LDPE) in a passive dosing experiment by inserting these matrices between thetwo sheets of PDMS for 48 h. The kinetics of mass transfer of fluoranthene between PDMS sheets in directcontact were a factor of 12 slower than those reported in the literature. The kinetics of mass transfer offluorene and phenanthrene through leaves were within the range of those previously reported for 2,4-dichlorophenoxyacetic acid through isolated cuticles. Our results provide a proof-of-concept demon-stration that the passive dosing method applied in this study can be used to measure the mass transfercoefficients of organic chemicals through leaves. Key recommendations for future experiments are toload the PDMS at the highest feasible concentrations to avoid working at analyte levels close to the limitof detection, to keep the leaves moist and to minimize potential pathways for contamination of the PDMSsheets by exposure to laboratory air.

  • 19. Ainsbury, E A
    et al.
    Bakhanova, E
    Barquinero, J F
    Brai, M
    Chumak, V
    Correcher, V
    Darroudi, F
    Fattibene, P
    Gruel, G
    Guclu, I
    Horn, S
    Jaworska, A
    Kulka, U
    Lindholm, C
    Lloyd, D
    Longo, A
    Marrale, M
    Monteiro Gil, O
    Oestreicher, U
    Pajic, J
    Rakic, B
    Romm, H
    Trompier, F
    Veronese, I
    Voisin, P
    Vral, A
    Whitehouse, C A
    Wieser, A
    Woda, C
    Wojcik, Andrzej
    Stockholm University, Faculty of Science, Department of Genetics, Microbiology and Toxicology.
    Rothkamm, K
    REVIEW OF RETROSPECTIVE DOSIMETRY TECHNIQUES FOR EXTERNAL IONISING RADIATION EXPOSURES.2011In: Radiation Protection Dosimetry, ISSN 0144-8420, E-ISSN 1742-3406, Vol. 147, no 4, p. 573-592Article in journal (Refereed)
    Abstract [en]

    The current focus on networking and mutual assistance in the management of radiation accidents or incidents has demonstrated the importance of a joined-up approach in physical and biological dosimetry. To this end, the European Radiation Dosimetry Working Group 10 on 'Retrospective Dosimetry' has been set up by individuals from a wide range of disciplines across Europe. Here, established and emerging dosimetry methods are reviewed, which can be used immediately and retrospectively following external ionising radiation exposure. Endpoints and assays include dicentrics, translocations, premature chromosome condensation, micronuclei, somatic mutations, gene expression, electron paramagnetic resonance, thermoluminescence, optically stimulated luminescence, neutron activation, haematology, protein biomarkers and analytical dose reconstruction. Individual characteristics of these techniques, their limitations and potential for further development are reviewed, and their usefulness in specific exposure scenarios is discussed. Whilst no single technique fulfils the criteria of an ideal dosemeter, an integrated approach using multiple techniques tailored to the exposure scenario can cover most requirements.

  • 20. Akselsson, Cecilia
    et al.
    Belyazid, Salim
    Stockholm University, Faculty of Science, Department of Physical Geography.
    Critical biomass harvesting - Applying a new concept for Swedish forest soils2018In: Forest Ecology and Management, ISSN 0378-1127, E-ISSN 1872-7042, Vol. 409, p. 67-73Article in journal (Refereed)
    Abstract [en]

    The contribution of forest harvesting to base cation losses and soil acidification has increased in recent years in Sweden, as the demand for bioenergy has increased and the sulphur deposition has decreased. Thus, new policy tools are required to evaluate the progress of the recovery from acidification, and as a basis for forest management recommendations. In this study we introduce and test a concept, Critical biomass harvesting. The concept builds on the concept Critical loads, which has been used world-wide for several decades as a bridge between science and policies related to transboundary air pollution and acidification. The basis for the concept is an acidity mass balance, with sources and sinks of acidity. A critical limit defines the highest acceptable acidification status of the water leaving the root zone. Based on the critical limit, the highest allowed biomass harvesting can be calculated, keeping the other parameters constant. In this study the critical limit was set to ANC (Acid Neutralizing Capacity) = 0. Nitrogen was assumed to be affecting acidity only if it leaches from the root zone. The critical biomass harvesting was calculated for almost 12000 National Forest Inventory sites with spruce and pine forest, using the best available data on deposition, weathering and nitrogen leaching. The exceedance of critical biomass harvesting was calculated as the difference between the estimated harvest losses and the critical biomass harvesting. The results were presented as median values in merged catchments in a catchment database, with totally 2079 merged catchments in Sweden. According to the calculations, critical biomass harvesting was exceeded in the southern half of Sweden already at stem harvesting in spruce forests. Whole-tree harvesting expanded the exceedance area, and increased the exceedance levels in southern Sweden. The exceedance in pine forest was lower and affected smaller areas. It was concluded that the concept of critical biomass harvesting can be successfully applied on the same database that has been used for critical load calculations in Sweden, using basically the same approach as has been extensively applied, evaluated and discussed in a critical load context. The results from the calculations in Sweden indicate that whole-tree harvesting, without wood ash recycling, can be expected to further slow down recovery, especially in the most acidified parts of the country, in the southwest.

  • 21. Alexandre, Ana
    et al.
    Silva, Joao
    Buapet, Pimchanok
    Stockholm University, Faculty of Science, Department of Botany.
    Björk, Mats
    Stockholm University, Faculty of Science, Department of Botany.
    Santos, Rui
    Effects of CO2 enrichment on photosynthesis, growth, and nitrogen metabolism of the seagrass Zostera noltii2012In: Ecology and Evolution, ISSN 2045-7758, Vol. 2, no 10, p. 2620-2630Article in journal (Refereed)
    Abstract [en]

    Seagrass ecosystems are expected to benefit from the global increase in CO2 in the ocean because the photosynthetic rate of these plants may be C-i-limited at the current CO2 level. As well, it is expected that lower external pH will facilitate the nitrate uptake of seagrasses if nitrate is cotransported with H+ across the membrane as in terrestrial plants. Here, we investigate the effects of CO2 enrichment on both carbon and nitrogen metabolism of the seagrass Zostera noltii in a mesocosm experiment where plants were exposed for 5 months to two experimental CO2 concentrations (360 and 700 ppm). Both the maximum photosynthetic rate (Pm) and photosynthetic efficiency (alpha) were higher (1.3- and 4.1-fold, respectively) in plants exposed to CO2-enriched conditions. On the other hand, no significant effects of CO2 enrichment on leaf growth rates were observed, probably due to nitrogen limitation as revealed by the low nitrogen content of leaves. The leaf ammonium uptake rate and glutamine synthetase activity were not significantly affected by increased CO2 concentrations. On the other hand, the leaf nitrate uptake rate of plants exposed to CO2-enriched conditions was fourfold lower than the uptake of plants exposed to current CO2 level, suggesting that in the seagrass Z. noltii nitrate is not cotransported with H+ as in terrestrial plants. In contrast, the activity of nitrate reductase was threefold higher in plant leaves grown at high-CO2 concentrations. Our results suggest that the global effects of CO2 on seagrass production may be spatially heterogeneous and depend on the specific nitrogen availability of each system. Under a CO2 increase scenario, the natural levels of nutrients will probably become limiting for Z. noltii. This potential limitation becomes more relevant because the expected positive effect of CO2 increase on nitrate uptake rate was not confirmed.

  • 22. Allan, Ian J.
    et al.
    Nilsson, Hans C.
    Tjensvoll, Ingrid
    Stockholm University, Faculty of Science, Department of Systems Ecology.
    Bradshaw, Clare
    Stockholm University, Faculty of Science, Department of Systems Ecology.
    Naes, Kristoffer
    PCDD/F release during benthic trawler-induced sediment resuspension2012In: Environmental Toxicology and Chemistry, ISSN 0730-7268, E-ISSN 1552-8618, Vol. 31, no 12, p. 2780-2787Article in journal (Refereed)
    Abstract [en]

    Benthic trawling can cause the resuspension of large amounts of sediments. Such regular practice in the Grenland fjord system in the south of Norway has the potential to affect the fate, movement, and bioavailability of sediment-associated polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). A novel mode of exposing passive sampling devices consisting of towing semipermeable membrane devices attached to the trawl net was used to gauge in situ changes in the freely dissolved concentration of PCDD/Fs on benthic trawlerinduced sediment resuspension. Significant accumulation of a number of PCDD/F congeners was observed despite the short (5?h) sampler exposure times. On average, a one order of magnitude increase in freely dissolved PCCD/F concentrations was seen within minutes of the sediment being resuspended. This observation was supported by similar changes in filtered PCDD/F concentrations measured by high-volume sampling prior to resuspension and in the sediment plume. Environ. Toxicol. Chem. 2012; 31: 27802787.

  • 23. Allen, Lisa Zeigler
    et al.
    McCrow, John P.
    Ininbergs, Karolina
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences. Stockholm University, Science for Life Laboratory (SciLifeLab).
    Dupont, Christopher L.
    Badger, Jonathan H.
    Hoffman, Jeffery M.
    Ekman, Martin
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences. Stockholm University, Science for Life Laboratory (SciLifeLab).
    Allen, Andrew E.
    Bergman, Birgitta
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences. Stockholm University, Science for Life Laboratory (SciLifeLab).
    Venter, J. Craig
    The Baltic Sea Virome: Diversity and Transcriptional Activity of DNA and RNA Viruses2017In: mSystems, ISSN 2379-5077, Vol. 2, no 1, article id UNSP e00125-16Article in journal (Refereed)
    Abstract [en]

    Metagenomic and metatranscriptomic data were generated from size-fractionated samples from 11 sites within the Baltic Sea and adjacent marine waters of Kattegat and freshwater Lake Tornetrask in order to investigate the diversity, distribution, and transcriptional activity of virioplankton. Such a transect, spanning a salinity gradient from freshwater to the open sea, facilitated a broad genome-enabled investigation of natural as well as impacted aspects of Baltic Sea viral communities. Taxonomic signatures representative of phages within the widely distributed order Caudovirales were identified with enrichments in lesser-known families such as Podoviridae and Siphoviridae. The distribution of phage reported to infect diverse and ubiquitous heterotrophic bacteria (SAR11 clades) and cyanobacteria (Synechococcus sp.) displayed population-level shifts in diversity. Samples from higher-salinity conditions (>14 practical salinity units [PSU]) had increased abundances of viruses for picoeukaryotes, i.e., Ostreococcus. These data, combined with host diversity estimates, suggest viral modulation of diversity on the whole-community scale, as well as in specific prokaryotic and eukaryotic lineages. RNA libraries revealed single-stranded DNA (ssDNA) and RNA viral populations throughout the Baltic Sea, with ssDNA phage highly represented in Lake Tornetrask. Further, our data suggest relatively high transcriptional activity of fish viruses within diverse families known to have broad host ranges, such as Nodoviridae (RNA), Iridoviridae (DNA), and predicted zoonotic viruses that can cause ecological and economic damage as well as impact human health. IMPORTANCE Inferred virus-host relationships, community structures of ubiquitous ecologically relevant groups, and identification of transcriptionally active populations have been achieved with our Baltic Sea study. Further, these data, highlighting the transcriptional activity of viruses, represent one of the more powerful uses of omics concerning ecosystem health. The use of omics-related data to assess ecosystem health holds great promise for rapid and relatively inexpensive determination of perturbations and risk, explicitly with regard to viral assemblages, as no single marker gene is suitable for widespread taxonomic coverage.

  • 24. Almeida, Joao
    et al.
    Schobesberger, Siegfried
    Kuerten, Andreas
    Ortega, Ismael K.
    Kupiainen-Maatta, Oona
    Praplan, Arnaud P.
    Adamov, Alexey
    Amorim, Antonio
    Bianchi, Federico
    Breitenlechner, Martin
    David, Andre
    Dommen, Josef
    Donahue, Neil M.
    Downard, Andrew
    Dunne, Eimear
    Duplissy, Jonathan
    Ehrhart, Sebastian
    Flagan, Richard C.
    Franchin, Alessandro
    Guida, Roberto
    Hakala, Jani
    Hansel, Armin
    Heinritzi, Martin
    Henschel, Henning
    Jokinen, Tuija
    Junninen, Heikki
    Kajos, Maija
    Kangasluoma, Juha
    Keskinen, Helmi
    Kupc, Agnieszka
    Kurten, Theo
    Kvashin, Alexander N.
    Laaksonen, Ari
    Lehtipalo, Katrianne
    Leiminger, Markus
    Leppa, Johannes
    Loukonen, Ville
    Makhmutov, Vladimir
    Mathot, Serge
    McGrath, Matthew J.
    Nieminen, Tuomo
    Olenius, Tinja
    Onnela, Antti
    Petaja, Tuukka
    Riccobono, Francesco
    Riipinen, Ilona
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Rissanen, Matti
    Rondo, Linda
    Ruuskanen, Taina
    Santos, Filipe D.
    Sarnela, Nina
    Schallhart, Simon
    Schnitzhofer, Ralf
    Seinfeld, John H.
    Simon, Mario
    Sipila, Mikko
    Stozhkov, Yuri
    Stratmann, Frank
    Tome, Antonio
    Troestl, Jasmin
    Tsagkogeorgas, Georgios
    Vaattovaara, Petri
    Viisanen, Yrjo
    Virtanen, Annele
    Vrtala, Aron
    Wagner, Paul E.
    Weingartner, Ernest
    Wex, Heike
    Williamson, Christina
    Wimmer, Daniela
    Ye, Penglin
    Yli-Juuti, Taina
    Carslaw, Kenneth S.
    Kulmala, Markku
    Curtius, Joachim
    Baltensperger, Urs
    Worsnop, Douglas R.
    Vehkamaki, Hanna
    Kirkby, Jasper
    Molecular understanding of sulphuric acid-amine particle nucleation in the atmosphere2013In: Nature, ISSN 0028-0836, E-ISSN 1476-4687, Vol. 502, no 7471, p. 359-+Article in journal (Refereed)
    Abstract [en]

    Nucleation of aerosol particles from trace atmospheric vapours is thought to provide up to half of global cloud condensation nuclei(1). Aerosols can cause a net cooling of climate by scattering sunlight and by leading to smaller but more numerous cloud droplets, which makes clouds brighter and extends their lifetimes(2). Atmospheric aerosols derived from human activities are thought to have compensated for a large fraction of the warming caused by greenhouse gases(2). However, despite its importance for climate, atmospheric nucleation is poorly understood. Recently, it has been shown that sulphuric acid and ammonia cannot explain particle formation rates observed in the lower atmosphere(3). It is thought that amines may enhance nucleation(4-16), but until now there has been no direct evidence for amine ternary nucleation under atmospheric conditions. Here we use the CLOUD (Cosmics Leaving OUtdoor Droplets) chamber at CERN and find that dimethylamine above three parts per trillion by volume can enhance particle formation rates more than 1,000-fold compared with ammonia, sufficient to account for the particle formation rates observed in the atmosphere. Molecular analysis of the clusters reveals that the faster nucleation is explained by a base-stabilization mechanism involving acid-amine pairs, which strongly decrease evaporation. The ion-induced contribution is generally small, reflecting the high stability of sulphuric acid-dimethylamine clusters and indicating that galactic cosmic rays exert only a small influence on their formation, except at low overall formation rates. Our experimental measurements are well reproduced by a dynamical model based on quantum chemical calculations of binding energies of molecular clusters, without any fitted parameters. These results show that, in regions of the atmosphere near amine sources, both amines and sulphur dioxide should be considered when assessing the impact of anthropogenic activities on particle formation.

  • 25.
    Amelina, Hanna
    Stockholm University, Faculty of Science, Department of Biochemistry and Biophysics.
    Proteomics in biomarker research: Insights into the effects of aging and environment on biological systems2011Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Proteomics is the global analysis of proteins that covers a broad range of technologies aimed at determining the identity and quantity of proteins expressed in the cell, their three-dimensional structure and interaction partners. In contrast to genome, proteome reflects more accurately on the dynamic state of the cell, tissue, or an organism. Therefore much is expected from proteomics to yield better disease markers for early diagnosis and therapy monitoring, as well as biomarkers that would indicate environmental exposure or provide prediction of biological age.

    In this thesis, I have developed and applied robust and sensitive subproteomic approaches to study the effect of aging as well as and environmental pollution using different animal models.

    In the first part, a high-throughput proteomic method based on liquid chromatography coupled to 2-dimensional gel electrophoresis (LC/2-DE) was developed. The usefulness of this method has been demonstrated by applying it to the assessment of marine pollution in a field experiment.

    Next, I have utilized this subproteomic approach to study the effect of aging in mouse kidney of both genders. As a result, a protein expression signature of aging kidney was obtained, revealing gender-dependent alterations in proteome profiles of aging mouse kidney.

    In order to further reduce the dynamic range of protein expression and increase the sensitivity of proteomic analysis, I have applied a shotgun mass spectrometry-based proteomic approach using isobaric tags for relative and absolute quantification (iTRAQ) coupled to liquid chromatography and tandem mass spectrometry (LC-MS/MS) to study age-related differences in peroxisome-enriched fractions from mouse liver. Only eight proteins showed statistically significant difference in expression (p<0.05) with moderate folds. This study indicates that age-depended changes in the liver proteome are minimal, suggesting that its proteome is efficiently maintained until certain age.

    Finally, in the context of aging studies and the role of peroxisomes in aging, I have tested the utility of cell-penetrating peptides (CPPs) as agents for protein delivery into acatalasemic peroxisomes using yeast as a model. The results obtained suggest that CPPs may be suitable for the delivery of antioxidants to peroxisomes and in future could provide a tool for the protein therapy of age-related diseases.

  • 26. Amstaetter, Katja
    et al.
    Eek, Espen
    Cornelissen, Gerard
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Sorption of PAHs and PCBs to activated carbon: Coal versus biomass-based quality2012In: Chemosphere, ISSN 0045-6535, E-ISSN 1879-1298, Vol. 87, no 5, p. 573-578Article in journal (Refereed)
    Abstract [en]

    The addition of activated carbon (AC) is an increasingly popular method for pollutant immobilization, and the AC material can be made of biomass or coal/fossil feedstock. The aim of the present study was to investigate whether there are differences between pollutant sorption to biomass and coal-based AC in the presence and absence of sediment. Through N-2 and CO2 adsorption to probe surface area and pore size it was shown that the biomass-based AC had a stronger dominance of narrow pores in the size range 3.5-15 angstrom than the anthracite-based material. In the absence of sediment, sorption isotherms for the probe compounds pyrene and PCB-101 showed stronger sorption for the biomass-based AC (logarithmic Freundlich coefficients 8.15 for pyrene; 9.91 for PCB-101) than for the anthracite-based one (logarithmic Freundlich coefficients 7.20 and 9.70, respectively). In the presence of sediment, the opposite trend was observed, with the stronger sorption for anthracite-based AC. Thus, the presence of competing and/or pore-blocking sediment constituents reduces sorption to a larger extent for biomass-derived AC (factor of 5 for pyrene to almost 100 for PCB-101) than for anthracite-based AC (no reduction for pyrene to factor of 5 for PCB-101). This difference is tentatively attributed to the difference in pore size distribution, narrow pores being more prone to clogging, and could have implications for remediation feasibility with AC from different sources.

  • 27. Anderies, J. M.
    et al.
    Carpenter, S. R.
    Steffen, Will
    Stockholm University, Faculty of Science, Stockholm Resilience Centre. Australian National University, Australia.
    Rockström, Johan
    Stockholm University, Faculty of Science, Stockholm Resilience Centre.
    The topology of non-linear global carbon dynamics: from tipping points to planetary boundaries2013In: Environmental Research Letters, ISSN 1748-9326, E-ISSN 1748-9326, Vol. 8, no 4, p. 044048-Article in journal (Refereed)
    Abstract [en]

    We present a minimal model of land use and carbon cycle dynamics and use it to explore the relationship between non-linear dynamics and planetary boundaries. Only the most basic interactions between land cover and terrestrial, atmospheric, and marine carbon stocks are considered in the model. Our goal is not to predict global carbon dynamics as it occurs in the actual Earth System. Rather, we construct a conceptually reasonable heuristic model of a feedback system between different carbon stocks that captures the qualitative features of the actual Earth System and use it to explore the topology of the boundaries of what can be called a 'safe operating space' for humans. The model analysis illustrates the existence of dynamic, non-linear tipping points in carbon cycle dynamics and the potential complexity of planetary boundaries. Finally, we use the model to illustrate some challenges associated with navigating planetary boundaries.

  • 28. Anderies, John M.
    et al.
    Folke, Carl
    Stockholm University, Faculty of Science, Stockholm Resilience Centre.
    Walker, Brian
    Östrom, Elinor
    Aligning Key Concepts for Global Change Policy: Robustness, Resilience, and Sustainability2013In: Ecology & society, ISSN 1708-3087, E-ISSN 1708-3087, Vol. 18, no 2, p. 8-Article in journal (Refereed)
    Abstract [en]

    Globalization, the process by which local social-ecological systems (SESs) are becoming linked in a global network, presents policy scientists and practitioners with unique and difficult challenges. Although local SESs can be extremely complex, when they become more tightly linked in the global system, complexity increases very rapidly as multi-scale and multi-level processes become more important. Here, we argue that addressing these multi-scale and multi-level challenges requires a collection of theories and models. We suggest that the conceptual domains of sustainability, resilience, and robustness provide a sufficiently rich collection of theories and models, but overlapping definitions and confusion about how these conceptual domains articulate with one another reduces their utility. We attempt to eliminate this confusion and illustrate how sustainability, resilience, and robustness can be used in tandem to address the multi-scale and multi-level challenges associated with global change.

  • 29. Anderson, Pippin
    et al.
    Elmqvist, Thomas
    Stockholm University, Stockholm Resilience Centre.
    Urban Ecological and Social-Ecological Research in the City of Cape Town: Insights Emerging from an Urban Ecology CityLab2012In: Ecology & society, ISSN 1708-3087, E-ISSN 1708-3087, Vol. 17, no 4, p. 23-Article in journal (Refereed)
  • 30.
    Andersson, August
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    A systematic examination of a random sampling strategy for source apportionment calculations2011In: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 412, p. 232-238Article in journal (Refereed)
    Abstract [en]

    Estimating the relative contributions from multiple potential sources of a specific component in a mixed environmental matrix is a general challenge in diverse fields such as atmospheric, environmental and earth sciences. Perhaps the most common strategy for tackling such problems is by setting up a system of linear equations for the fractional influence of different sources. Even though an algebraic solution of this approach is possible for the common situation with N + 1 sources and N source markers, such methodology introduces a bias, since it is implicitly assumed that the calculated fractions and the corresponding uncertainties are independent of the variability of the source distributions. Here, a random sampling (RS) strategy for accounting for such statistical bias is examined by investigating rationally designed synthetic data sets. This random sampling methodology is found to be robust and accurate with respect to reproducibility and predictability. This method is also compared to a numerical integration solution for a two-source situation where source variability also is included. A general observation from this examination is that the variability of the source profiles not only affects the calculated precision but also the mean/median source contributions.

  • 31.
    Andersson, August
    et al.
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Sheesley, Rebecca J.
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Krusa, Martin
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Johansson, Christer
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Gustafsson, Örjan
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    (14)C-Based source assessment of soot aerosols in Stockholm and the Swedish EMEP-Aspvreten regional background site2011In: Atmospheric Environment, ISSN 1352-2310, E-ISSN 1873-2844, Vol. 45, no 1, p. 215-222Article in journal (Refereed)
    Abstract [en]

    Combustion-derived soot or black carbon (BC) in the atmosphere has a strong influence on both climate and human health. In order to propose effective mitigation strategies for BC emissions it is of importance to investigate geographical distributions and seasonal variations of BC emission sources. Here, a radiocarbon methodology is used to distinguish between fossil fuel and biomass burning sources of soot carbon (SC). SC is isolated for subsequent off-line (14)C quantification with the chemothermal oxidation method at 375 degrees C (CTO-375 method), which reflects a recalcitrant portion of the BC continuum known to minimize inadvertent inclusion of any non-pyrogenic organic matter. Monitored wind directions largely excluded impact from the Stockholm metropolitan region at the EMEP-Aspvreten rural station 70 km to the south-west. Nevertheless, the Stockholm city and the rural stations yielded similar relative source contributions with fraction biomass (f(biomass)) for fall and winter periods in the range of one-third to half. Large temporal variations in (14)C-based source apportionment was noted for both the 6 week fall and the 4 month winter observations. The f(biomass) appeared to be related to the SC concentration suggesting that periods of elevated BC levels may be caused by increased wood fuel combustion. These results for the largest metropolitan area in Scandinavia combine with other recent (14)C-based studies of combustion-derived aerosol fractions to suggest that biofuel combustion is contributing a large portion of the BC load to the northern European atmosphere.

  • 32.
    Andersson, Camilla
    et al.
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Bergström, Robert
    Johansson, Christer
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Population exposure and mortality due to regional background PM in Europe – longterm simulations of source-region and shipping contributions2009In: Atmospheric Environment, ISSN 1352-2310, E-ISSN 1873-2844, Vol. 43, no 22-23, p. 3614-3620Article in journal (Refereed)
    Abstract [en]

    This paper presents the contribution to population exposure (PE) of regional background fine primary (PPM2.5) and secondary inorganic (SIA) particulate matter and its impact on mortality in Europe during 1997–2003 calculated with a chemistry transport model. Contributions to concentrations and PE due to emissions from shipping, Western (WEU), Eastern (EEU), and Northern Europe are compared.

    WEU contributes about 40% to both PPM2.5 and SIA concentrations, whereas the EEU contribution to PPM2.5 is much higher (43% of total PPM2.5) than to SIA (29% of total SIA). The population weighted average concentration (PWC) of PPM2.5 is a factor of 2.3 higher than average (non-weighted) concentrations, whereas for SIA the PWC is only a factor 1.6 higher. This is due to PPM2.5 concentrations having larger gradients and being relatively high over densely populated areas, whereas SIA is formed outside populated areas. WEU emissions contribute relatively more than EEU to PWC and mortality due to both PPM2.5 and SIA in Europe.

    The number of premature deaths in Europe is estimated to 301 000 per year due to PPM2.5 exposure and 245 000 due to SIA, despite 3.3 times higher average SIA concentrations. This is due to population weighting and assumed (and uncertain) higher relative risk of mortality for PPM2.5 components (2.8 times higher RR for PPM2.5). This study indicates that it might be more efficient, for the health of the European population, to decrease primary PM emissions (especially in WEU) than to decrease precursors of SIA, but more knowledge on the toxicity of different PM constituents is needed before firm conclusions can be drawn.

  • 33.
    Andersson, Erik
    et al.
    Stockholm University, Faculty of Science, Stockholm Resilience Centre.
    Barthel, Stephan
    Stockholm University, Faculty of Science, Stockholm Resilience Centre.
    Borgström, Sara
    Stockholm University, Faculty of Science, Stockholm Resilience Centre.
    Colding, Johan
    Elmqvist, Thomas
    Stockholm University, Faculty of Science, Stockholm Resilience Centre.
    Folke, Carl
    Stockholm University, Faculty of Science, Stockholm Resilience Centre. Royal Swedish Academy of Science, Beijer Institute, Sweden.
    Gren, Åsa
    Reconnecting Cities to the Biosphere: Stewardship of Green Infrastructure and Urban Ecosystem Services2014In: Ambio, ISSN 0044-7447, E-ISSN 1654-7209, Vol. 43, no 4, p. 445-453Article in journal (Refereed)
    Abstract [en]

    Within-city green infrastructure can offer opportunities and new contexts for people to become stewards of ecosystem services. We analyze cities as social-ecological systems, synthesize the literature, and provide examples from more than 15 years of research in the Stockholm urban region, Sweden. The social-ecological approach spans from investigating ecosystem properties to the social frameworks and personal values that drive and shape human interactions with nature. Key findings demonstrate that urban ecosystem services are generated by social-ecological systems and that local stewards are critically important. However, land-use planning and management seldom account for their role in the generation of urban ecosystem services. While the small scale patchwork of land uses in cities stimulates intense interactions across borders much focus is still on individual patches. The results highlight the importance and complexity of stewardship of urban biodiversity and ecosystem services and of the planning and governance of urban green infrastructure.

  • 34.
    Andersson, Erik
    et al.
    Stockholm University, Faculty of Science, Department of Systems Ecology. Stockholm University, Stockholm Resilience Centre.
    Bodin, Örjan
    Stockholm University, Faculty of Science, Department of Systems Ecology. Stockholm University, Stockholm Resilience Centre.
    Practical tool for landscape planning? An empirical investigation of network based models of habitat fragmentation.2009In: Ecography, ISSN 0906-7590, E-ISSN 1600-0587, Vol. 32, no 1, p. 123-132Article in journal (Refereed)
    Abstract [en]

    This study presents a graph-theoretical modelling approach using daily movements and habitat demands of different target bird species in an urban context to assess: 1) habitable land cover types, 2) threshold distances between patches of habitat, 3) the required minimum accessible habitat areas and 4) the effects of barriers and stepping stones. The modelling approach is tested using empirical data from field surveys in the urban area of Stockholm, Sweden.

    The results show that groups of small habitat patches can house the same species as larger contiguous patches as long as they are perceived as functionally connected by the inhabitant organisms. Furthermore, we found that binary habitat/non-habitat representations of the landscape could roughly explain the variation in species occurrence, as long as habitat was properly defined. However, the explanatory power of the landscape models increased when features of matrix heterogeneity such as stepping stones and barriers were accounted for.

    Synthesis and application: in a world where forest ecosystems are becoming increasingly fragmented there is an urgent need to find comprehensive and scientifically relevant methods for managing and planning ecosystems. This study shows that: 1) groups of well placed small habitat patches can, together, be sufficient to attract birds in intensively developed areas, 2) the presented modelling approach can help identify such groups of patches, 3) matrix heterogeneity should preferably be accounted for, and 4) proper assessments of habitable land cover types are important. Finally, we argue that the modelling approach applied here may substantially improve landscape management and planning at scales ranging from whole landscapes down to neighbourhoods.

  • 35.
    Andersson, Erik
    et al.
    Stockholm University, Faculty of Science, Stockholm Resilience Centre.
    Colding, Johan
    Stockholm University, Faculty of Science, Stockholm Resilience Centre.
    Understanding how built urban form influences biodiversity2014In: Urban Forestry & Urban Greening, ISSN 1618-8667, E-ISSN 1610-8167, Vol. 13, no 2, p. 221-226Article in journal (Refereed)
    Abstract [en]

    This study seeks to contribute to a more complete understanding of how urban form influences biodiversity by investigating the effects of green area distribution and that of built form. We investigated breeding bird diversity in three types of housing development with approximately the same amount of tree cover. No significant differences in terms of bird communities were found between housing types in any of the survey periods. However, detached housing, especially with interspersed trees, had more neotropical insectivores and higher overall diversity of insectivores. Based on our results and theory we suggest a complementary approach to managing biodiversity in urban landscapes - instead of maximising the value and quality of individual patches efforts could go into enhancing over-all landscape quality at the neighbourhood scale by splitting up part of the green infrastructure. The relatively small differences in bird communities also suggest that different stakeholder groups may be engaged in management.

  • 36.
    Andersson, Kim
    Stockholm University, Stockholm Resilience Centre, Stockholm Environment Institute.
    Multifunctional Wetlands and Stakeholder Engagement: Lessons from Sweden2012Report (Other academic)
    Abstract [en]

    Wetlands construction and restoration has been adopted as an agri-environmental measure in some of the Baltic Sea Region countries to help make agriculture more environmentally sustainable. However, Sweden’s experience shows that despite great efforts, the country only achieved 60% of its target of adding 12,000 hectares of wetlands in the agricultural landscape between 2000 and 2010.The main objective of this study, conducted within the EU-financed project Baltic COMPASS, was to draw lessons from Sweden’s wetland implementation and identify key enabling and disabling factors, especially in the governance system. Of special interest is to what extent wetlands can generate multiple benefits. The study is based on a participatory analysis involving interviews with professionals from governmental agencies, civil society organizations and the private sector, carried out in January to June 2012

  • 37.
    Andersson, Petter
    et al.
    Stockholm University, Faculty of Science, Department of Botany.
    Hambäck, Peter A.
    Stockholm University, Faculty of Science, Department of Botany.
    Immigration of olfactory searching insects into host plant patches: testing scaling rules for olfactory information2011In: Arthropod-Plant Interactions, ISSN 1872-8855, E-ISSN 1872-8847, Vol. 5, p. 269-277Article in journal (Refereed)
    Abstract [en]

    Herbivorous insects are commonly faced with host plants being distributed in scattered patches across a landscape. Immigration rates into habitat patches may strongly depend on the sensory cues used in the patch location process, and immigration rates of insects can be predicted based on the scaling of sensory cues. Here, we tested recent estimates of the scaling of olfactory information to patch size, which predicts a scaling coefficientf z = -0.5 (A^z, where A = patch size, z = scaling coefficient). We predicted that immigration rates of olfactory searching insects into patches of different sizes should scale according to the estimated slope. We investigated attraction of the weevils Cionus tuberculosus and Cionus scrophulariae to odors from figwort Scrophularia nodosa and quantified immigration rates of weevils into differently sized patches. We also investigated oviposition rates of the sawfly Tenthredo scrophulariae. The slope in the regression between density and patch size for herbivores was then compared with the predicted scaling coefficient. Using olfactometers, we found that weevils were attracted to figwort odors. Weevil densities were significantly affected by patch size, and the slope in the relationship between density and patch size was z = -0.53. The slope in the relationship between larval densities of sawflies and patch size was less negative with a slope of z = -0.15, indicating differences in search behavior compared with the weevils. The density–patch size relationship for the weevils closely matched the predicted slope and supported the previous estimations of the scaling of olfactory informationto patch size.

  • 38.
    Andersson, Petter
    et al.
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Löfstedt, Christer
    Lund Univ, Dept Biol..
    Hambäck, Peter
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Insect density-plant density relationships: a modified view of insect responses to resource concentrations2013In: Oecologia, ISSN 0029-8549, E-ISSN 1432-1939, Vol. 173, no 4, p. 1333-1344Article in journal (Refereed)
    Abstract [en]

    Habitat area is an important predictor of spatial variation in animal densities. However, the area often correlates with the quantity of resources within habitats, complicating our understanding of the factors shaping animal distributions. We addressed this problem by investigating densities of insect herbivores in habitat patches with a constant area but varying numbers of plants. Using a mathematical model, predictions of scale-dependent immigration and emigration rates for insects into patches with different densities of host plants were derived. Moreover, a field experiment was conducted where the scaling properties of odour-mediated attraction in relation to the number of odour sources were estimated, in order to derive a prediction of immigration rates of olfactory searchers. The theoretical model predicted that we should expect immigration rates of contact and visual searchers to be determined by patch area, with a steep scaling coefficient, mu = -1. The field experiment suggested that olfactory searchers should show a less steep scaling coefficient, with mu a parts per thousand -0.5. A parameter estimation and analysis of published data revealed a correspondence between observations and predictions, and density-variation among groups could largely be explained by search behaviour. Aphids showed scaling coefficients corresponding to the prediction for contact/visual searchers, whereas moths, flies and beetles corresponded to the prediction for olfactory searchers. As density responses varied considerably among groups, and variation could be explained by a certain trait, we conclude that a general theory of insect responses to habitat heterogeneity should be based on shared traits, rather than a general prediction for all species.

  • 39.
    Andersson, Petter
    et al.
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Löfstedt, Christer
    Hambäck, Peter A.
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    How insects sense olfactory patches: the spatial scaling of olfactory information2013In: Oikos, ISSN 0030-1299, E-ISSN 1600-0706, Vol. 122, no 7, p. 1009-1016Article in journal (Refereed)
    Abstract [en]

    When searching for resources in heterogeneous environments, animals must rely on their abilities to detect the resources via their sensory systems. However, variation in the strength of the sensory cue may be mediated by the physical size of the resource patch. Patch detection of insects are often predicted by the scaling of sensory cues to patch size, where visual cues has been proposed to scale proportional to the diameter of the patch. The scaling properties of olfactory cues are, however, virtually unknown. Here, we investigated scaling rules for olfactory information in a gradient of numbers of odour sources, relevant to odour-mediated attraction under field conditions. We recorded moth antennal responses to sex pheromones downwind from pheromone patches and estimated the slope in the scaling relationship between the effective length of the odour plumes and the number of odour sources. These measurements showed that the effective plume length increased proportional to the square root of the number of odour sources. The scaling relationship, as estimated in the field experiment, was then evaluated against field data of the slope in the relationship between trap catch and release rate of chemical attractants for a wide range of insects. This meta-analysis revealed an average slope largely consistent with the estimated scaling relationship between the effective plume length and the number of odour sources. This study is the first to estimate the scaling properties of olfactory cues empirically and has implications for understanding and predicting the spatial distributions of insects searching by means of olfactory cues in heterogeneous environments.

  • 40.
    André, Karin
    et al.
    Stockholm University, Stockholm Environment Institute.
    Bruzell, Susanna
    Centrum för miljö- och klimatforskning, Lunds universitet.
    Gerger Swartling, Åsa
    Stockholm University, Stockholm Environment Institute.
    Jönsson, Anna Maria
    Lagergren, Fredrik
    Vulturius, Gregor
    Stockholm University, Stockholm Environment Institute.
    Blennow, Kristina
    Carlsen, Henrik
    Stockholm University, Stockholm Environment Institute.
    Engström, Kerstin
    Hassler, John
    Stockholm University, Faculty of Social Sciences, Institute for International Economic Studies.
    Lindeskog, Mats
    Olsson, Olle
    Stockholm University, Stockholm Environment Institute.
    Klimatanpassat skogsbruk: drivkrafter, risker och möjligheter : Mistra-SWECIA syntesrapport2015Report (Other academic)
  • 41.
    André, Karin
    et al.
    Stockholm University, Stockholm Environment Institute. Centre for Climate Science and Policy Research, Department of Water and Environmental Studies, Linköping University.
    Jonsson, C. Anna
    Centre for Climate Science and Policy Research, Department of Water and Environmental Studies, Linköping University.
    Science-practice interactions linked to climate adaptation in two contexts: municipal planning and forestry in Sweden2015In: Journal of Environmental Planning and Management, ISSN 0964-0568, E-ISSN 1360-0559, Vol. 58, no 2, p. 297-314Article in journal (Refereed)
    Abstract [en]

    This paper examines the science-practice interface in the process of adapting to climate change in society. This paper analyses science-based stakeholder dialogues with climate scientists, municipal officers and private individual forest owners in Sweden, and examines how local experts both share scientific knowledge and experience and integrate it into their work strategies and practices. The results demonstrate how local experts jointly conceptualise climate adaptation, how scientific knowledge is domesticated among local experts in dialogue with scientific experts, the emergence of anchoring devices, and the boundary-spanning functions that are at work in the respective sectors.

  • 42.
    André, Karin
    et al.
    Centre for Climate Science and Policy Research, Linköping University.
    Simonsson, Louise
    Department of Thematic Studies—Water and Environmental Studies, Linköping University.
    Gerger Swartling, Åsa
    Stockholm University, Stockholm Resilience Centre, Stockholm Environment Institute.
    Linnér, Björn-Ola
    Centre for Climate Science and Policy Research, Linköping University.
    Method Development for Identifying and Analysing Stakeholders in Climate Change Adaptation Processes2012In: Journal of Environmental Policy and Planning, ISSN 1523-908X, E-ISSN 1522-7200, Vol. 14, no 3, p. 243-261Article in journal (Refereed)
    Abstract [en]

    It is now widely recognized that stakeholder interaction and dialogue is essential to improve decisions about and awareness of climate change. The term ‘stakeholder’ is broad and researchers and practitioners may have interrelated and contrasting views on who is a stakeholder or who is (or should be) responsible for adaptation to climate change. To engage stakeholders in research or other projects on adaptation thus requires a careful mapping of the stakeholder landscape and identification of relevant actors at different levels. Through a case study approach, based on studies of two Swedish urban regions, Stockholm and Gothenburg, this paper proposes a systematic method to analyse and identify roles and responsibilities in the stakeholder landscape. The initial mapping exercise was complemented by participatory studies of local and regional stakeholders’ perceptions of who is, or should be, involved in adaptation and their significance for climate change adaptation in the respective regions. The results indicate the value of careful stakeholder analysis for sustainable, effective, planned adaptation that is flexible, but also systematic enough to fulfil practical and scientific requirements for the study and advancement of ongoing adaptation processes and implementation.

  • 43.
    Andrén, Cecilia M.
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Toxicity of Inorganic Aluminium in Humic Streams2012Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Aluminium (Al) has been recognised as a main toxic factor alongside pH in acidified water ecosystems. The toxic effect of Al has been attributed to inorganic Al (Ali), though there are few in situ studies in ambient humic waters which are the focus of this thesis.

    The aim was to estimate Ali toxicity and thus also Ali concentrations in Swedish humic streams. Subsequently it is necessary to analyse Ali correctly, which was studied by modelling and method intercalibrations. The hypothesis was that the effect of Ali could be followed via physiological effects and Al accumulation, as well as by mortality. Toxicity was studied by in stream exposures of brown trout (Salmo trutta L.) and two salmonid prey organisms (Gammarus pulex and Baetis rhodani) during spring flood.

    The modelling of the Ali fraction was performed using monitoring data covering all of Sweden with satisfactory results. The essential variables for Ali modelling were determined; Al, DOC, pH and F, while Fe, Ca and Mg had less effect. The automated analytical procedure for Ali (with cation exchange followed by complexation with pyrocatechol violet) was modified and validated and showed to be the preferred method for laboratory analyses.

    To avoid detrimental effects for brown trout Ali should be <20 µg/L and pH >5.0; mortality was high when the Ali was above 50 µg/L. The invertebrates were more sensitive, as mortalities occurred at pH <6.0 and Ali >15 µg/L for G. pulex, and at pH <5.7 and Ali >20 µg/L for B. rhodani. It is prudent to use a wide view and let the most sensitive species set the tolerance limits; a pH above 5.7-6.0 and Ali below 15-20 µg/L allows the stream ecosystems to thrive.

    Today, as waters are recovering from acidification, the aim of mitigating liming is to carefully adjust dosage to avoid suboptimal water quality. The thresholds found in this thesis can be used to efficiently but carefully decrease liming, as both Ali and pH levels have to be balanced to sustain the recovering aquatic biota.

  • 44.
    Andrén, Cecilia M.
    et al.
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Eriksson Wiklund, Ann-Kristin
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Response of Gammarus pulex and Baetis rhodani to springtime acid episodes in humic brooksManuscript (preprint) (Other academic)
    Abstract [en]

    Although the acid load has decreased throughout Scandinavia, episodic acidification continues to affect stream biology by temporarily decreasing pH levels and mobilising aluminium. These events are becoming more common as climate change renders more frequent and intense storm floods. The transient acidity can reduce fish populations, but fish food resources can also be impaired because macro-invertebrates are affected. In this in-stream study, two salmonid prey organisms (Gammarus pulex and Baetis rhodani) were exposed to snowmelt in six humic brooks with a natural gradient of pH and inorganic monomeric Al (Ali). We hypothesise that there are thresholds for acid toxicity that can be defined by mortality and changes in body elemental content. Mortality was observed and the whole body content of base cations (BC, i.e., Ca, Mg, Na and K) and metals (Al, Fe, Zn and Mn) were determined. Both species began to die and the total bodily BC content decreased as the pH levels decreased and the Ali concentrations increased. In contrast to what has been observed for fish gills, no accumulation of Al was observed. The invertebrate body Na content decreased when the pH level decreased, which indicated that the osmoregulation in both species was affected. The Ca content in G. pulex and the Mg content in B. rhodani diverged from the general BC-pattern by increasing when the pH level decreased. The mortality increased drastically at pH <6.0 and Ali >15 μg/L for G. pulex and at pH <5.7 and Ali >20 μg/L for the somewhat less sensitive B. rhodani. Although Ali is tightly correlated to pH, the local Al availability in soil and bedrock also affect the Al release and toxic Ali episodes can consequently arise in some catchment areas. The estimated values can be used as water quality thresholds to adjust lime dose because both Ali and pH levels have to be balanced to prevent harm in recovering stream ecosystems.

  • 45.
    Andrén, Cecilia M.
    et al.
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Eriksson Wiklund, Ann-Kristin
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Response of Gammarus pulex and Baetis rhodani to springtime acid episodes in humic brooks2013In: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 463, p. 690-699Article in journal (Refereed)
    Abstract [en]

    While chronic acidification of water bodies has been steadily decreasing, episodic acidification continues to affect stream biology by temporarily decreasing pH and mobilizing aluminum. These events are becoming more common as climate change renders more frequent and intense storms and flooding. Throughout Scandinavia, the effects of acidification have been mitigated by liming since the 1980s, but remediation efforts can now be reduced. While transient acidity may reduce fish populations, also other species in streams are affected. In this in-stream study, two macro-invertebrates (Gammarus pulex and Baetis rhodani), both known as salmonid prey organisms, were exposed to snowmelt in six humic brooks with a natural gradient of pH and inorganic monomeric Al (Al-i). We hypothesize that acid toxicity thresholds can be defined using lethal (mortality) and sublethal (changes in body elemental content) metrics. Periodic observations were made of mortality and whole body concentrations of base cations (BC: Ca, Mg, Na and K) and metals (Al, Fe, Zn and Mn). Mortality increased dramatically at pH < 6.0 and Al-i > 15 mu g/L for G. pulex and at pH < 5.7 and Al-i > 20 mu g/L for B. rhodani. No accumulation of Al was found. The invertebrate body Na concentration decreased when pH dropped, suggesting that osmoregulation in both species was affected. In contrast to general BC pattern, Ca concentration in G. pulex and Mg concentration in B. rhodani increased when pH decreased. Although Ali strongly correlates to pH, the Al composition of soil and bedrock also influences Al availability, potentially contributing to toxic Al; episodes. The estimated values calculated in this study can be used to improve water quality criteria and as thresholds to adjust doses of lime compared to old recommendations in ongoing liming programs. Such adjustments may be critical since both Ali and pH levels have to be balanced to mitigate damage to recovering stream ecosystems.

  • 46.
    Andrén, Cecilia M.
    et al.
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Kroglund, Frode
    Norwegian Institute for Water Research (NIVA), Grimstad , Norway.
    Teien, Hans-Christian
    Agricultural University of Norway, Department of Plant and Environmental Sciences, Aas, Norway.
    Controlled exposure of brown trout to humic water limed to different pH and inorganic aluminium concentrations2006In: Verhandlungen / Internationale Vereinigung für Theoretische und Angewandte Limnologie, ISSN 0368-0770, Vol. 29, p. 1548-1552Article in journal (Refereed)
    Abstract [en]

    Fish that accumulated more than 800 μg Al/g dw gill and 900 μg Fe/g dw gill died at pH 4.6 but survived at higher pH. Fish experienced severe physiological responses when gill-Al exceeded 600 μg Al/g. Fish having less than 200 μg Al/g had a satisfactory health status based on the variables monitored. The observation of between-strain variation response suggests that some variation in the dose-response model must considered or that stream specific water quality guidelines needs to be developed.The fish responses and gill-Al can be translated to water quality criteria. Acceptable water quality over a 7-day period for 11-cm yearlings was obtained in water having < 60 μg Ali/L. Following liming, this level was achieved within 15 min at a pH target of 6.0,within 140 min at a pH target of 5.5 (see companionpaper, TEIEN et al. 2005). However care should betaken when applying these criteria to streams, as they will not protect more sensitive life stages at reproductionand hatching.

  • 47.
    Andrén, Cecilia M.
    et al.
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Rydin, Emil
    Uppsala universitet, Institutionen för ekologi och genetik .
    Toxicity of inorganic aluminium at spring snowmelt—In-stream bioassays withbrown trout (Salmo trutta L.)2012In: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 437, p. 422-432Article in journal (Refereed)
    Abstract [en]

    Although the acid load has decreased throughout Scandinavia, acidic soils still mobilise aluminium (Al) thatis harmful to brown trout. We hypothesise that there are thresholds for Al toxicity and that the toxicity can betraced from the water content to gill accumulation and the consequential physiological effects. During snowmelt,yearlings were exposed to a gradient of pH and inorganic monomeric Al (Ali) in humic streams to studythe toxic effects and mortality. Gill Al and physiological blood analyses [haemoglobin (Hb), plasma chloride(P-Cl) and glucose (Glu)] were measured. As the water quality deteriorated, Al accumulated on the gills; Hband Glu increased; P-Cl decreased, and mortality occurred. Moribund fish had significantly increased gill Aland Hb, suggesting that respiratory disturbances contributed to mortality. Decreased P-Cl and plasmaavailability indicated an ion regulatory disturbance and possibly circulatory collapse. Ali should be lessthan 20 μg/L, and pH higher than 5.0, to sustain healthy brown trout populations. These thresholds can beused to fine-tune lime dose, as both Ali and pH levels have to be balanced to prevent harm in the recoveringaquatic biota. Although Al is tightly linked to pH, local variation in Al availability in soil and bedrock affectsthe Al release and subsequent toxic Ali episodes in some catchment areas.

  • 48. Angeler, David G.
    et al.
    Allen, Craig R.
    Barichievy, Chris
    Eason, Tarsha
    Garmestani, Ahjond S.
    Graham, Nicholas A. J.
    Granholm, Dean
    Gunderson, Lance H.
    Knutson, Melinda
    Nash, Kirsty L.
    Nelson, R. John
    Nyström, Magnus
    Stockholm University, Faculty of Science, Stockholm Resilience Centre.
    Spanbauer, Trisha L.
    Stow, Craig A.
    Sundstrom, Shana M.
    Management applications of discontinuity theory2016In: Journal of Applied Ecology, ISSN 0021-8901, E-ISSN 1365-2664, Vol. 53, no 3, p. 688-698Article, review/survey (Refereed)
    Abstract [en]

    1. Human impacts on the environment are multifaceted and can occur across distinct spatiotemporal scales. Ecological responses to environmental change are therefore difficult to predict, and entail large degrees of uncertainty. Such uncertainty requires robust tools for management to sustain ecosystem goods and services and maintain resilient ecosystems. 2. We propose an approach based on discontinuity theory that accounts for patterns and processes at distinct spatial and temporal scales, an inherent property of ecological systems. Discontinuity theory has not been applied in natural resource management and could therefore improve ecosystem management because it explicitly accounts for ecological complexity. 3. Synthesis and applications. We highlight the application of discontinuity approaches for meeting management goals. Specifically, discontinuity approaches have significant potential to measure and thus understand the resilience of ecosystems, to objectively identify critical scales of space and time in ecological systems at which human impact might be most severe, to provide warning indicators of regime change, to help predict and understand biological invasions and extinctions and to focus monitoring efforts. Discontinuity theory can complement current approaches, providing a broader paradigm for ecological management and conservation.

  • 49. Angelstam, Per
    et al.
    Andersson, Kjell
    Annerstedt, Matilda
    Axelsson, Robert
    Elbakidze, Marine
    Garrido, Pablo
    Grahn, Patrik
    Jonsson, K. Ingemar
    Pedersen, Simen
    Schlyter, Peter
    Stockholm University, Faculty of Science, Department of Physical Geography and Quaternary Geology.
    Skärbäck, Erik
    Smith, Mike
    Stjernquist, Ingrid
    Stockholm University, Faculty of Science, Department of Physical Geography and Quaternary Geology.
    Solving Problems in Social-Ecological Systems: Definition, Practice and Barriers of Transdisciplinary Research2013In: Ambio, ISSN 0044-7447, E-ISSN 1654-7209, Vol. 42, no 2, p. 254-265Article in journal (Refereed)
    Abstract [en]

    Translating policies about sustainable development as a social process and sustainability outcomes into the real world of social-ecological systems involves several challenges. Hence, research policies advocate improved innovative problem-solving capacity. One approach is transdisciplinary research that integrates research disciplines, as well as researchers and practitioners. Drawing upon 14 experiences of problem-solving, we used group modeling to map perceived barriers and bridges for researchers' and practitioners' joint knowledge production and learning towards transdisciplinary research. The analysis indicated that the transdisciplinary research process is influenced by (1) the amount of traditional disciplinary formal and informal control, (2) adaptation of project applications to fill the transdisciplinary research agenda, (3) stakeholder participation, and (4) functional team building/development based on self-reflection and experienced leadership. Focusing on implementation of green infrastructure policy as a common denominator for the delivery of ecosystem services and human well-being, we discuss how to diagnose social-ecological systems, and use knowledge production and collaborative learning as treatments.

  • 50.
    Applegate, Patrick J.
    et al.
    Stockholm University, Faculty of Science, Department of Physical Geography and Quaternary Geology.
    Kirchner, Nina
    Stockholm University, Faculty of Science, Department of Physical Geography and Quaternary Geology.
    Stone, E. J.
    Keller, K.
    Greve, R.
    An assessment of key model parametric uncertainties in projections of Greenland ice sheet behavior2012In: The Cryosphere, ISSN 1994-0416, E-ISSN 1994-0424, Vol. 6, no 3, p. 589-606Article in journal (Refereed)
    Abstract [en]

    Lack of knowledge about the values of ice sheet model input parameters introduces substantial uncertainty into projections of Greenland Ice Sheet contributions to future sea level rise. Computer models of ice sheet behavior provide one of several means of estimating future sea level rise due to mass loss from ice sheets. Such models have many input parameters whose values are not well known. Recent studies have investigated the effects of these parameters on model output, but the range of potential future sea level increases due to model parametric uncertainty has not been characterized. Here, we demonstrate that this range is large, using a 100-member perturbed-physics ensemble with the SICOPOLIS ice sheet model. Each model run is spun up over 125 000 yr using geological forcings and subsequently driven into the future using an asymptotically increasing air temperature anomaly curve. All modeled ice sheets lose mass after 2005 AD. Parameters controlling surface melt dominate the model response to temperature change. After culling the ensemble to include only members that give reasonable ice volumes in 2005 AD, the range of projected sea level rise values in 2100 AD is similar to 40 % or more of the median. Data on past ice sheet behavior can help reduce this uncertainty, but none of our ensemble members produces a reasonable ice volume change during the mid-Holocene, relative to the present. This problem suggests that the model's exponential relation between temperature and precipitation does not hold during the Holocene, or that the central-Greenland temperature forcing curve used to drive the model is not representative of conditions around the ice margin at this time (among other possibilities). Our simulations also lack certain observed physical processes that may tend to enhance the real ice sheet's response. Regardless, this work has implications for other studies that use ice sheet models to project or hindcast the behavior of the Greenland Ice Sheet.

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