| 1. |
- Hubendick, Bengt, 1916-2012
(author)
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Människa - miljö - överlevnad
- 1990
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In: Kulturmiljövård. - Stockholm : Riksantikvarieämbetet. - 1100-4800. ; [15]:2, s. 19-25
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Journal article (pop. science, debate, etc.)
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| 2. |
- Odén, Birgitta, 1921-2016
(author)
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Miljön som historia
- 1990
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In: Kulturmiljövård. - Stockholm : Riksantikvarieämbetet. - 1100-4800. ; [15]:2, s. 9-18
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Journal article (pop. science, debate, etc.)
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| 3. |
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| 4. |
- Arsenie, Irina, et al.
(author)
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Effects of Gamma Irradiation on an Aquatic Fulvic Acid
- 1991
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In: Humic substances in the aquatic and terrestrial environment : proceedings of an international symposium, Linköping, Sweden, August 21-23, 1989. - Berlin Heidelberg New York : Springer. - 3540537023 ; , s. 233-241
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Book chapter (peer-reviewed)abstract
- An aquatic fulvic acid was irradiated with gamma radiation from a 60Co-source (dose range 0-48 Mrad), as part of a larger study of the transformation and decomposition of humic substances in natura! aquatic systems. Experiments were performed at two concentrations (1000 mg/l and 100 mg/l) and at various pH-values (2-10). The fulvic acid transformation was studied by monitoring optical density (UV-spectroscopy ), molecular weight distribution (GPC-technique) and total dissolved organic carbon (TOC). A general decrease in TOC with increasing radiation dose was observed: the initial G-value of about 5 decreased with the increasing dose to a minimum value of 0.2-0.3. A simultaneous increase in molecular weight (Mn rose from approximately 2000 to a maximum of about 4000) was observed in the acidic samples (pH 2-4) at a dose below 10 Mrad. Natural background radiation can significantly contribute to the degradation of dissolved humic substances in deep groundwaters, considering the observed G-value for low doses (about 5) and the otherwise high chemical stability of the fulvic acid fraction even after long residence times (103-104 y) in the ground.
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| 5. |
- Asplund, Gunilla, et al.
(author)
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Soil Peroxidase-Mediated Chlorination of Fulvic Acid
- 1991
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In: Humic substances in the aquatic and terrestrial environment : proceedings of an international symposium, Linköping, Sweden, August 21-23, 1989. - Berlin Heidelberg New York : Springer. - 3540537023 ; , s. 474-483
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Book chapter (peer-reviewed)abstract
- Humic matter has recently been shown to contain considerable quantities of naturally produced organohalogens. The present study investigated the possibility of a non-specific, enzymatically mediated halogenation of organic matter in soil. The results showed that, in the presence of chloride and hydrogen peroxide, the enzyme chloroperox1dase (CPO) from the fungus Caldariomyces fumago catalyzes chlorination of fulvic acid. At pH 2.5 - 6.0, the chlorine to fulvic acid ratio in the tested sample was elevated from 12 mg/g to approximately 40-50 mg/g. It was also shown that this reaction can take place at chloride and hydrogen peroxide concentrations found in the environment. An extract from spruce forest soil was shown to have a measurable chlorinating capacity. The activity of an extract of 0.5 kg soil corresponded to approximately 0.3 enzyme units, measured as CPO activity. Enzymatically mediated halogenation of humic substances may be one of the mechanisms explaining the w1despread occurrence of adsorbable organic halogens (AOX) in soil and water.
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| 6. |
- Colding, Johan
(author)
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Analysis of hunting options by the use of general food taboos
- 1998
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In: Ecological Modelling. - 0304-3800 .- 1872-7026. ; 110:1, s. 5-17
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Journal article (peer-reviewed)abstract
- A hypothetical model was built, using the STELLA II software program, to test several hunting options for a human hunting group. Different outcomes of possible hunting modes are analysed, such as a change in hunting rate, prey hunted, or species avoided or not avoided by taboos. The model consists of five sectors that reflect a short food chain in an upper Amazonian ecosystem. There is a vegetation sector, a predator sector, and two sectors consisting of browsers and grazers. The last sector represents a human group, known as the Ecuador Achuar. The critical factor analysed is how differences in hunting rate affect a target resource, and how this resource may be affected by general food taboos. The major results of the model are that general food taboos may not be an adaptive short term strategy for hunters, but that a 'moderate' hunting mode may be the most effective option for the human group. Since the model is a simplification of the real world, no general conclusions for management should be drawn from the results.
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| 7. |
- Colding, Johan, et al.
(author)
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The relations among threatened species, their protection, and taboos
- 1997
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In: Conservation Ecology. - 1195-5449. ; 1:1
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Journal article (peer-reviewed)abstract
- We analyzed the role of taboos for the protection of species listed as "threatened" by the World Conservation Union (IUCN), and also for species known to be endemic and keystone. The study was limited to taboos that totally avoid or prohibit any use of particular species and their populations. We call them specific-species taboos. Through a literature review, 70 currently existing examples of specific-species taboos were identified and analyzed. The species avoided were grouped into biological classes. Threat categories were determined for each species, based on the IUCN Red Data Book. We found that ≃ 30% of the identified taboos prohibit any use of species listed as threatened by IUCN. Of the specific-species taboos, 60% are set on reptiles and mammals. In these two classes, ≃ 50% of the species are threatened, representing all of the threatened species in our analysis, with the exception of one bird species. Both endemic and keystone species that are important for ecosystem functions are avoided by specific-species taboos. Specific-species taboos have important ecological ramifications for the protection of threatened and ecologically important populations of species. We do not suggest that specific-species taboos are placed on species because they are, or have been, endangered; instead, we emphasize that species are avoided for a variety of other reasons. It is urgent to identify and analyze resource practices and social mechanisms of traditional societies, such as taboos, and to investigate their possible ecological significance. Although it may provide insights of value for conservation, not only of species,
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| 8. |
- Grimvall, Anders, et al.
(author)
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Phytotoxic Substances in Runoff from Forested Catchment Areas
- 1991
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In: Humic substances in the aquatic and terrestrial environment : proceedings of an international symposium, Linköping, Sweden, August 21-23, 1989. - Berlin Heidelberg New York : Springer. - 3540537023 ; , s. 397-406
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Book chapter (peer-reviewed)abstract
- Runoff from different catchment areas in southem Sweden was tested in a root bioassay based on solution cultures of cucumber seedlings. Water samples from agricultural catchment areas produced no signs at all or only weak signs of inhibited root growth, whereas several water samples from catchmcnt areas dominated by mires or coniferous forests produced visible root injuries. The most severe root injuries (very short roots, discolouration, swelling of root tips and lack of root hairs) were caused by samples from a catchment area without local emissions and dominated by old stands of spruce. Fractionation by ultrafiltration showed that the phytotoxic effect of these samples could be attributed to organic matter with a nominal molecular-weight exceeding 1000 or to substances associated with organic macromolecules. Experiments aimed at concentrating phytotoxic compounds from surface water indicated that the observed growth inhibition was caused by strongly hydrophilic substances. Previous reports on phytotoxic, organic substances of natura! origin have emphasized interaction between plants growing close together. The presence of phytotoxic substances in runoff indicates that there is also a large-scale dispersion of such compounds.
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| 9. |
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| 10. |
- Härlin, Mikael
(author)
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Tree-thinking and nemertean systematics, with a systematization of the Eureptantia
- 1998
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In: Hydrobiologia. - 0018-8158 .- 1573-5117. ; 365:1, s. 33-46
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Journal article (peer-reviewed)abstract
- I review how some influential nemertean systematistshave perceived and illustrated phylogenetic trees andargue that the nineteenth century nemerteantaxonomists still influence many contemporarynemertean taxonomists to a high degree. By showing hownineteenth century systematics differs from moremodern views on trees, I hope to convey the advantagesof a cladistic approach to tree-thinking and nemerteansystematics. Furthermore I propose a systematizationof the Eureptantia that illustrates the cladisticapproach to tree-thinking but, more importantly, isalso a better representation of eureptantic phylogenythan previous classifications.
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| 11. |
- Johannesson, Mikael, 1959-
(author)
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Risk Management Under Uncertainty : Strategies for protecting health and the environment
- 1998
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Doctoral thesis (other academic/artistic)abstract
- This thesis deals with problems related to the management of environmental and health risks and problems. The general hypothesis of this work was that there are possibilities of making considerable improvements in the decision analysis and management of complicated environmental and health risks and problems. Specific attention has been paid to decision-situations involving great uncertainty and to how different decision-makers handle these extraordinarily difficult risk management situations. The studies focus on the risk management of the threat of anthropogenic climate change and chemical hazards, and on the legal and administrative risk management system in Sweden.A general conclusion is that there is room for considerable improvement in the risk management of environmental and health risks in the investigated areas. Increased use of decision theory and development of priority-setting strategies are two important tools for such improvement. Further, increased attention to the following issues will also contribute to improved risk managment: 1) the demarcation of the analysis, 2) surprises and worst cases, 3) separation and identification of scientific and non-scientific issues, 4) the distribution of the burden of proof, and 5) the scientists' and regulators' different roles.It can be concluded from the experience reported in the four papers in this thesis that it is fruitful to combine different perspectives when studying risks and the management of risk in a comprehensive approach. Three perspectives have been identified and used: (I) the actor perspective, (II) the cause perspective and (III) the risk/problem perspective. The three perspectives complement each other by giving different kinds of information eventhough they are closely linked together. A general model applicable to all kinds of risks has been developed. It serves to conceptualize the three perspectives and the three levels where it is possible to take action against risks/problems. Papers II and IV are detailed studies of more narrow issues compared to the other two more comprehensive studies.In paper (I) we compare three legal and administrative systems of risk management in Sweden, namely those responsible for work environment, environmental protection, and chemicals control. Large differences were found in terms of the organizational structures and the general modi operandi of government activities in the three areas. Many of these differences seem to be the result, not of deliberate choice but rather of the lack of coordination between policy areas. It is concluded that systematic comparisons of experiences from different areas can be helpful in improving the efficiency of risk management.Paper (II) is a case study of how the Government, governmental agencies and private companies acted when a dye stuff and a chemical marking agent were introduced to the Swedish market. Their activities are compared to the Swedish act and ordinance on chemical products. The introduction of these chemicals was given big attention in the Swedish newspapers and other media during the winter of 1993/94 when several health problems were reported and related to these substances. It is concluded that the introduction of the chemicals did not comply with the Swedish chemicals legislation. The responsibility to make risk assessments and the reversed burden of proof principle are two fundamental bases of the legislation which were set aside. It is also concluded that the unusual actions and role of the Government in this decision process may explain the actions and positions of the authorities and the companies.Paper (III) is a decision-theoretical study of an extraordinary complex risk management and decision problem - the threat of an anthropogenic climate change. The problem involves a multitude of both natural and social causal factors and a large amount of scientific uncertainty. We found that the method used in all economic decision-studies of global warming that we are aware of is more risk-taking than the standard method used in risk analysis - the expected utility method. We argue that more attention should be paid in the scientific community to less probable but more serious effect scenarios and that a less risk-taking method of analysis should be used. We also argue that the standard method of discounting future costs is inadequate, misleading, and probably not consistent with the concept of sustainable development. We conclude that the principle of sustainable development, the scientific uncertainty, the risk of irreversible damages and the long time lag from negotiations to the point in time when most of the reversible damages will be gone, all together imply that we should reduce anthropogenic emissions of greenhouse gases and that we should act as soon as possible.Paper (IV) examines reasons for and the importance of analysing worst case scenarios and surprises in the area of anthropogenic climate change. Three main reasons are given for assuming that a worst case scenario may be realised: 1) The unpredictibility of the climate system, 2) historical experiences, and 3) conceivable severe scenarios and mechanisms. Although the uncertainty of surprises is huge by definition, and the probability of worst case scenarios cannot be assessed, there are reasons for and ways of incorporating them into the risk analysis. Not including them in the analysis could very well mean that the largest risk is excluded and that decision makers make a more risk-taking decision than they would otherwise have made. However, the IPCC (Intergovernmental panel on climate change) have avoided analysis of the possibility of worst case scenarios and major factors that could give rise to such scenarios. Possible reasons why the IPCC have not included them in their analysis are discussed.
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| 12. |
- Nilsson, Ulla, et al.
(author)
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Long-Term Studies of Fungicide Concentrations in Greenhouses. 3. Exposure Risks after Spraying in Greenhouses.
- 1996
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In: Journal of Agricultural and Food Chemistry. - : American Chemical Society (ACS). - 0021-8561 .- 1520-5118. ; 44:9, s. 2885-2888
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Journal article (peer-reviewed)abstract
- The study presented concerns the dermal exposure risks during harvest work in greenhouses after fungicide application. The contamination of the fungicide vinclozolin on clothes, overalls and gloves, worn during harvest after application was investigated. The fungicide was extracted from the cloth with 1-chlorobutane and finally determined with HPLC. The average amount of fungicide found on the clothes, the potential exposure, was 25 mg after 8 h of work in the greenhouse. It was estimated that most of the fungicide amount was found on gloves. Assuming a maximum uptake of vinclozolin (on bare skin) of 10%, the value of the dermal exposure was estimated to be 2.5 mg/day. In the absence of threshold values for dermal, exposure a comparison was made with recommended values for acceptable daily intake of foodstuffs. This comparison reveals that the assumed dermal exposure is higher than the value set by the U.S. Environmental Protection Agency but lower than the value given by the World Health Organization. Thus, the use of protective garments during harvesting, especially on the hands, is recommended.
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| 13. |
- Nordén, Maria, et al.
(author)
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Interaction of Strontium and Europium with an Aquatic Fulvic Acid Studied by Ultrafiltration and lon Exchange Techniques
- 1991
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In: Humic substances in the aquatic and terrestrial environment : proceedings of an international symposium, Linköping, Sweden, August 21-23, 1989. - Berlin Heidelberg New York : Springer. - 3540537023 ; , s. 297-303
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Book chapter (peer-reviewed)abstract
- The complexation of an aquatic fulvic acid, FA, with Sr2+ and Eu3+ was studied using an ultrafiltration technique and an ion exchange distribution method. The total amount of bound metal (Sr2+ and Eu3+) was measured as a function of pH at low meta! concentrations (trace levels) and constant FA concentration. In the Sr-FA system the bound meta! fraction increased slightly with pH, and the values obtained from the two experimental techniques were comparable. For Eu-FA, according to the ultrafiltration data, the fraction of bound meta! ion was relatively insensitive to pH changes, whereas values from the ion exchange measurements showed a strong and positive dependence on pH. The results are discussed in the light of possible intrinsic problems of the two methods.
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| 14. |
- Pettersson, Catharina, et al.
(author)
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Dating of groundwaters by ¹⁴C-analysis of dissolved humic substances
- 1991
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In: Humic substances in the aquatic and terrestrial environment : proceedings of an international symposium, Linköping, Sweden, August 21-23, 1989. - Berlin Heidleberg New York : Springer. - 3540537023 ; , s. 135-141
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Book chapter (peer-reviewed)abstract
- Fulvic acids of the DOC of five deep (139-409 m) groundwaters were recovered (adsorption on DEAE-cellulose) and used for age determination (14C determined by accelerator mass spectrometry), and compared with fulvic acids recovered from a shallow groundwater and a surface water. The composition of the seven different fulvic acids was similar, despite variations in hydrochemical conditions and residence times, indicating a high stability of this molecular weight fraction. The ages calculated from the 14C-content of the fulvic acid fraction (600 to 10000 y) are less than the ages indicated from analyses of the dissolved carbonate (data available for three sites). Using a fraction of the DOC with high stability (like the fulvic acid fraction) as a 14C-source when assessing the ages of subsurface waters, appears to be superior to using dissolved carbonate.
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| 15. |
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| 16. |
- Sundberg, Per, et al.
(author)
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There is no support for Jensen's hypothesis of nemerteans as ancestors to the vertebrates
- 1998
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In: Hydrobiologia. - 0018-8158 .- 1573-5117. ; 365:1, s. 47-54
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Journal article (peer-reviewed)abstract
- Nemerteans (phylum Nemertea) have been viewed by mostzoologists as descended from, or closely related to,the flatworms. This view is based mainly on theirsupposedly acoelomate body. Their ancestry, however,is a point of controversy and there is evidence for acoelomate, protostomous origin. Notwithstanding thesedifferent views, most zoologists consider nemerteansto be phylogenetically distant from the chordates.Four authors (Hubrecht, Macfarlane, Jensen, Willmer),however, have postulated that nemerteans instead areclosely related to the chordates and that they sharea most recent common ancestor with the vertebrates. We argue that this view is based on a flawed view ofhomology and of seeing evolution as a series ofprogressions, which has no support in modernevolutionary thinking. Since there are nomorphological synapomorphies supporting aChordata-Nemertea clade, these authors instead guesswhat characteristics in extant nemerteans gave rise tocharacters observed in recent chordates. For example,they propose that the nemertean proboscis sheath hasevolved into the notochord. This is mere speculation,lacking testable propositions and is hence void ofinformation, and thus becomes futile in our view. However, the idea of a nemertean-vertebrate sisterrelationship as such is a testable hypotheses, and wetest it by applying the parsimony criterion to a setof morphological characters, and a set of molecular(the 18S rRNA gene) characters. Both tests reject thehypothesis.
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