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  • 1. Ahlgren, Joakim
    et al.
    Djodjic, Faruk
    Borjesson, G.
    Mattsson, L.
    Identification and quantification of organic phosphorus forms in soils from fertility experiments2013In: Soil use and management, ISSN 0266-0032, E-ISSN 1475-2743, Vol. 29, 24-35 p.Article in journal (Refereed)
    Abstract [en]

    The effects of soil type, crop rotation, fertilizer type and application rate on the composition of organic phosphorus (P) compounds in soils from four sites in a Swedish long-term fertilizer experiment were investigated with 31P-NMR. Soil textures investigated were loamy sand, sandy loam, silty clay loam and clay. Phosphorus has been added to the soils since the 1950s and 1960s at four different rates in the form of either mineral fertilizer or a combination of manure and mineral fertilizer. Results show that in soils receiving no P addition, most of the soil P was present in the form of phosphate monoesters (6070%, depending on soil type). However, a P addition equivalent to the amount of P removed annually by harvest altered this relationship so that the soils were dominated by orthophosphate instead. This trend became more obvious with increasing P addition. At the greatest P application rate, orthophosphate comprised 70% or more of the total extracted P in all the soils. These changes in the soil were due entirely to increase in orthophosphate, because the amounts of monoesters did not change with increasing P additions. This was true both for mineral fertilizer and the combination of manure and mineral fertilizer P. Soil type and crop rotation did not influence the results. The results indicate that there is no apparent build-up of organic P in the soils, but that P addition mainly affects the orthophosphate amounts in the soils regardless of form or amount of fertilizer.

  • 2. Ahlgren, Joakim
    et al.
    Djodjic, Faruk
    Wallin, Mats
    Barium as a Potential Indicator of Phosphorus in Agricultural Runoff2012In: Journal of Environmental Quality, ISSN 0047-2425, E-ISSN 1537-2537, Vol. 41, no 1, 208-216 p.Article in journal (Refereed)
    Abstract [en]

    In many catchments, anthropogenic input of contaminants, and in particular phosphorus (P), into surface water is a mixture of agricultural and sewage runoff. Knowledge about the relative contribution from each of these sources is vital for mitigation of major environmental problems such as eutrophication. In this study, we investigated whether the distribution of trace elements in surface waters can be used to trace the contamination source. Water from three groups of streams was investigated: streams influenced only by agricultural runoff, streams influenced mainly by sewage runoff, and reference streams. Samples were collected at different flow regimes and times of year and analyzed for 62 elements using ICP-MS. Our results show that there are significant differences between the anthropogenic sources affecting the streams in terms of total element composition and individual elements, indicating that the method has the potential to trace anthropogenic impact on surface waters. The elements that show significant differences between sources are strontium (p < 0.001), calcium (p < 0.004), potassium (p < 0.001), magnesium (p < 0.001), boron (p < 0.001), rhodium (p = 0.001), and barium (p < 0.001). According to this study, barium shows the greatest potential as a tracer for an individual source of anthropogenic input to surface waters. We observed a strong relationship between barium and total P in the investigated samples (R-2 = 0.78), which could potentially be used to apportion anthropogenic sources of P and thereby facilitate targeting of mitigation practices.

  • 3.
    Bergquist, Ann-Kristin
    et al.
    Umeå University, Faculty of Social Sciences, Department of Geography and Economic History.
    Keskitalo, E. Carina H.
    Umeå University, Faculty of Social Sciences, Department of Geography and Economic History.
    Regulation versus deregulation: Policy divergence between Swedish forestry and the Swedish pulp and paper industry after the 1990s2016In: Forest Policy and Economics, ISSN 1389-9341, E-ISSN 1872-7050, Vol. 73, 10-17 p.Article in journal (Refereed)
    Abstract [en]

    This article reviews the divergence of environmental regulatory arrangements in the Swedish forestry sector in relation to the closely-linked Swedish pulp and paper industry. The study finds that while the Swedish forestry sector was deregulated in 1993, with decreased state intervention in forest management, the pulp and paper sector has remained controlled by strong national mandatory requirements which have been further strengthened by European Union Directives after the 1990s. We suggest that one reason for the persistent, strict mandatory regulation of the pulp and paper sector is that conflicting goals between environmental protection and production growth have been aligned through technological change, while such a strong alignment of conflicting interests has not been possible to achieve in the forestry sector. Thus, policy divergence between the forestry and the pulp and paper industries may be explained by the success of established regulatory paths in the case of the pulp and paper industry, while in forestry deregulation has instead been used to, at least formally, increase focus on protection of the environment while maintaining a high level of productivity. Further studies in other sectors and countrieswill be necessary to clarify the specific role of, for example, discourses of deregulation and concepts of competitive advantage concerning e.g. particular actor's roles in specific elements of regulative change.

  • 4. Blanchet, Guillaume
    et al.
    Gavazov, Konstantin
    Umeå University, Faculty of Science and Technology, Department of Ecology and Environmental Sciences.
    Bragazza, Luca
    Sinaj, Sokrat
    Responses of soil properties and crop yields to different inorganic and organic amendments in a Swiss conventional farming system2016In: Agriculture, Ecosystems & Environment, ISSN 0167-8809, E-ISSN 1873-2305, Vol. 230, 116-126 p.Article in journal (Refereed)
    Abstract [en]

    In agro-ecosystems, fertilization practices are crucial for sustaining crop productivity. Here, based on a 50-year long-term experiment, we studied the influence of fertilization practices (inorganic and/or organic) and nitrogen (N) application rates on (i) soil physicochemical properties, (ii) microbial and earthworm communities and (iii) crop production. Our results showed that soil organic carbon content was increased by incorporation of crop residues (+2.45%) and farmyard manure application (+6.40%) in comparison to the use of mineral fertilizer alone. In contrast, soil carbon stock was not significantly affected by these fertilization practices. Overall, only farmyard manure application improved soil physicochemical properties compared to mineral fertilization alone. Soil microbial population was enhanced by the application of organic amendments as indicated by microbial biomass and phospholipid-derived fatty acids contents. The fertilization practices and the N application rates affected significantly both the biomass and composition of earthworm populations, especially the epigeic and endogeic species. Finally, farmyard manure application significantly increased crop yield (+3.5%) in comparison to mineral fertilization alone. Crop residue incorporation rendered variable but similar crop yields over the 50-year period. The results of this long-term experiment indicate that the use of organic amendments not only reduces the need for higher amount of mineral N fertilizer but also improves the soil biological properties with direct effects on crop yield.

  • 5.
    Brodin, Tomas
    et al.
    Umeå University, Faculty of Science and Technology, Department of Ecology and Environmental Sciences.
    Johansson, Frank
    Umeå University, Faculty of Science and Technology, Department of Ecology and Environmental Sciences.
    Bergsten, Johannes
    Umeå University, Faculty of Science and Technology, Department of Ecology and Environmental Sciences.
    Predator related oviposition site selection of aquatic beetles (Hydroporus spp.) and effects on offspring life-history2006In: Freshwater Biology, ISSN 0046-5070, E-ISSN 1365-2427, Vol. 51, no 7, 1277-1285 p.Article in journal (Refereed)
    Abstract [en]

    1. Theory predicts that natural selection should favour females that are able to correctly assess the risk of predation and then use that information to avoid high-risk oviposition sites to reduce the risk of offspring predation. Despite the potential significance of such behaviour on individual fitness, population dynamics and community structure, relatively few studies of oviposition behaviour connected to the risk of predation have been carried out.

    2. However, some recent studies suggest that oviposition site selection in response to risk of predation may be a common phenomenon, at least among amphibians and mosquitoes. A vast majority of previous studies have, however, neglected to investigate how the offspring are affected, in terms of fitness related parameters, by the maternal oviposition site choice.

    3. In an outdoor artificial pond experiment we tested the oviposition site selection of female aquatic beetles (Hydroporus spp.) in relation to the presence or absence of a predatory fish (Perca fluviatilis). In addition, we monitored how the oviposition site selection affected the behaviour, growth and food resource of the progeny.

    4. We show that free-flying females of the aquatic beetles Hydroporus incognitus and H. nigrita prefer to oviposit in waters without fish compared with waters with fish. Larval activity of Hydroporus spp. was unaffected by fish presence. Our results indicate that beetle larvae from females that do lay eggs in waters with fish show increased growth compared with larvae in waters without fish. We explain this difference in growth by a higher per-capita food supply in the presence of a fish predator. This finding may have important implications for our understanding of how the variance of oviposition site selection in a population is sustained.

  • 6. Buckland, Paul C.
    et al.
    Buckland, Philip I.
    Umeå University, Faculty of Arts, Archaeology and Sami Studies.
    Hughes, Damian
    Palaeoecological evidence for the Vera hypothesis?2005In: Large herbivores in the wildwood and modern naturalistic grazing systems, English Nature , 2005, 62-116 p.Chapter in book (Other academic)
    Abstract [en]

    This report stems from work commissioned by English Nature into the role of largeherbivores in the post-glacial landscape of Britain and the potential for using free-ranginggrazing animals to create and maintain diverse landscape mosaics in modern conditions.Some aspects may be disputed or considered controversial; it is an active field of research.Therefore we stress that the views expressed are those of the authors at the current time.Subsequent research may confirm our views or lead us to modify them.We hope they will be useful in future discussions, both within English Nature and inconservation land-management circles more generally.

  • 7.
    Buckland, Philip I.
    Umeå University, Faculty of Arts, Department of historical, philosophical and religious studies, Environmental Archaeology Lab.
    Lessons from extinctions2017In: Wood wise Woodland Conservation News, 22-27 p.Article in journal (Other (popular science, discussion, etc.))
    Abstract [en]

    Many beetles are very good at colonising new areas when changes in the landscape open up new possibilities. Equally, they are highly susceptible to local extinction in the face of landscape scale changes in their environment.

  • 8. Burdon, J.J.
    et al.
    Ericson, Lars E.
    Umeå University, Faculty of Science and Technology, Department of Ecology and Environmental Sciences.
    Thrall, P.H.
    Emerging plant diseases2014In: Encyclopedia of agriculture and food systems: volume 3 / [ed] Neal K. Van Alfen, San Diego: Academic Press, 2014, 2, 59-67 p.Chapter in book (Refereed)
  • 9. Carr, Joel A.
    et al.
    D'Odorico, Paolo
    Suweis, Samir
    Seekell, David A.
    Umeå University, Faculty of Science and Technology, Department of Ecology and Environmental Sciences.
    What commodities and countries impact inequality in the global food system?2016In: Environmental Research Letters, ISSN 1748-9326, E-ISSN 1748-9326, Vol. 11, no 9, 095013Article in journal (Refereed)
    Abstract [en]

    The global distribution of food production is unequal relative to the distribution of human populations. International trade can increase or decrease inequality in food availability, but little is known about how specific countries and commodities contribute to this redistribution. We present a method based on the Gini coefficient for evaluating the contributions of country and commodity specific trade to inequality in the global food system. We applied the method to global food production and trade data for the years 1986-2011 to identify the specific countries and commodities that contribute to increasing and decreasing inequality in global food availability relative to food production. Overall, international trade reduced inequality in food availability by 25%-33% relative to the distribution of food production, depending on the year. Across all years, about 58% of the total trade links acted to reduce inequality with similar to 4% of the links providing 95% of the reduction in inequality. Exports from United States of America, Malaysia, Argentina, and Canada are particularly important in decreasing inequality. Specific commodities that reduce inequality when traded include cereals and vegetables. Some trade connections contribute to increasing inequality, but this effect is mostly concentrated within a small number of commodities including fruits, stimulants, and nuts. In terms of specific countries, exports from Slovenia, Oman, Singapore, and Germany act to increase overall inequality. Collectively, our analysis and results represent an opportunity for building an enhanced understanding of global-scale patterns in food availability.

  • 10. De Long, Jonathan R.
    et al.
    Laudon, Hjalmar
    Blume-Werry, Gesche
    Umeå University, Faculty of Science and Technology, Department of Ecology and Environmental Sciences.
    Kardol, Paul
    Nematode community resistant to deep soil frost in boreal forest soils2016In: Pedobiologia, ISSN 0031-4056, E-ISSN 1873-1511, Vol. 59, no 5-6, 243-251 p.Article in journal (Refereed)
    Abstract [en]

    As global climate change advances, shifts in winter precipitation are becoming more common in high latitude ecosystems, resulting in less insulating snow cover and deeper soil frost. Long-term alterations to soil frost can impact on ecosystem processes such as decomposition, microbial activity and vegetation dynamics. In this study we utilized the longest running, well-characterized soil frost manipulation experiment in a boreal forest. We measured nematode family composition and feeding group abundances at four different soil layer depths from plots that had been subjected to deep soil frost for one and 11 years. The overall abundance of nematodes and the different feeding groups were unaffected by deep soil frost. However, a higher Maturity Index was weakly associated with deep soil frost (indicative of lower nutrient enrichment and more persister nematode (i.e., K-strategist) families), likely due to the loss of nutrients and reduced inputs from inhibited decomposition. Multivariate and regression analyses showed that most nematode families were weakly associated with dominant understory plant species and strongly associated with soil organic matter (SOM). This is probably the result of higher resource availability in the control plots, which is favorable to the nematode community. These results indicate that the nematode community was more strongly driven by the long-term indirect effects of deep soil frost on SOM as opposed to the direct effects. Our findings highlight that the indirect effects of altered winter precipitation and soil frost patterns may be more important than direct winter climate effects. Further, such indirect effects on SOM and the plant community that may affect the nematode community can only be seen in long-term experiments. Finally, given the critical role nematodes play in soil food webs and carbon and nutrient cycling, our results demonstrate the necessity of considering the response of nematodes to global climate change in boreal forest soils. 

  • 11.
    Dressel, Sabrina
    et al.
    Sveriges lantbruksuniversitet .
    Sandström, Camilla
    Umeå University, Faculty of Social Sciences, Department of Political Science.
    Ericsson, Göran
    Sveriges lantbruksuniversitet .
    A meta-analysis of studies on attitudes toward bears and wolves across Europe 1976–20122015In: Conservation Biology, ISSN 0888-8892, E-ISSN 1523-1739, Vol. 29, no 2, 565-574 p.Article in journal (Refereed)
    Abstract [en]

    The ranges of wolves (Canis lupus) and bears (Ursus arctos) across Europe have expanded recently, and it is important to assess public attitudes toward this expansion because responses toward these species vary widely. General attitudes toward an object are good predictors of broad behavioral patterns; thus, attitudes toward wolves and bears can be used as indicators to assess the social foundation for future conservation efforts. However, most attitude surveys toward bears and wolves are limited in scope, both temporally and spatially, and provide only a snapshot of attitudes. To extend the results of individual surveys over a much larger temporal and geographical range so as to identify transnational patterns and changes in attitudes toward bears and wolves over time, we conducted a meta-analysis. Our analysis included 105 quantitative surveys conducted in 24 countries from 1976 to 2012. Across Europe, people's attitudes were more positive toward bears than wolves. Attitudes toward bears became more positive over time, but attitudes toward wolves seemed to become less favorable the longer people coexisted with them. Younger and more educated people had more positive attitudes toward wolves and bears than people who had experienced damage from these species, and farmers and hunters had less positive attitudes toward wolves than the general public. For bears attitudes among social groups did not differ. To inform conservation of large carnivores, we recommend that standardized longitudinal surveys be established to monitor changes in attitudes over time relative to carnivore population development. Our results emphasize the need for interdisciplinary research in this field and more advanced explanatory models capable of capturing individual and societal responses to changes in large carnivore policy and management.

  • 12. Eklöf, Karin
    et al.
    Bishop, Kevin
    Bertilsson, Stefan
    Björn, Erik
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Buck, Moritz
    Umeå University, Faculty of Science and Technology, Department of Chemistry. National Bioinformatics Infrastructure Sweden, Uppsala SE-75236, Sweden.
    Skyllberg, Ulf
    Osman, Omneya A.
    Kronberg, Rose-Marie
    Bravo, Andrea G.
    Formation of mercury methylation hotspots as a consequence of forestry operations2018In: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 613-614, 1069-1078 p.Article in journal (Refereed)
    Abstract [en]

    Earlier studies have shown that boreal forest logging can increase the concentration and export of methylmercury (MeHg) in stream runoff. Here we test whether forestry operations create soil environments of high MeHg net formation associated with distinct microbial communities. Furthermore, we test the hypothesis that Hg methylation hotspots are more prone to form after stump harvest than stem-only harvest, because of more severe soil compaction and soil disturbance. Concentrations of MeHg, percent MeHg of total Hg (THg), and bacterial community composition were determined at 200 soil sampling positions distributed across eight catchments. Each catchment was either stem-only harvested (n = 3), stem-and stump-harvested (n = 2) or left undisturbed (n = 3). In support of our hypothesis, higher MeHg to THg ratios was observed in one of the stump-harvested catchments. While the effects of natural variation could not be ruled out, we noted that most of the highest % MeHg was observed in water-filled cavities created by stump removal or driving damage. This catchment also featured the highest bacterial diversity and highest relative abundance of bacterial families known to include Hg methylators. We propose that water-logged and disturbed soil environments associated with stump harvest can favor methylating microorganisms, which also enhance MeHg formation. 

  • 13.
    Ekström, Magnus
    Centre of Biostochastics, Swedish University of Agricultural Sciences, Umeå.
    Quantifying spatial patterns of landscapes2003In: Ambio, ISSN 0044-7447, E-ISSN 1654-7209, Vol. 32, no 8, 573-576 p.Article in journal (Refereed)
    Abstract [en]

    In this paper we discuss information theoretical landscape indices based on data from digitized maps in grid format: measures based on Shannon's entropy, e.g. the measures of diversity and contagion; and measures based on conditional entropy, e.g. a new index which can be seen as an alternative to the measure of contagion that does not have the disadvantage of being highly correlated to the measure of diversity. We also introduce a measurement on how much information Is contained in a coarse-scale map about a fine-scale map.

  • 14.
    Ericson, Göran
    et al.
    Institutionen för vilt, fiske och miljö. SLU.
    Dahl, Fredrik
    Institutionen för vilt, fiske och miljö. SLU.
    Sandström, Camilla
    institutionen för vilt, fisk och miljö, SLU.
    Färre svenskar lämnar asfaltsdjungeln: En vanlig uppfattning är att svensken med sitt starka engagemang för naturen har stort intresse av att vara i skog och mark2009In: Miljötrender. Nyheter och resultat från SLU, ISSN 1403-4743, no 3, 3-5 p.Article in journal (Other academic)
    Abstract [sv]

    Varje år genomför SLU-forskare en brevundersökning till ett representativt urval av den svenska befolkningen i åldern 16 – 65 år för att se om vår inställning till djur, natur och val av friluftsaktiviteter har förändrats1. År 1980 sa 92 procent av den svenska befolkningen att de var mycket eller ganska intresserade av att vara i ”skog och mark”. Förra året sa 82 procent av svenskarna samma sak. Det är en nedgång med tio procent på knappt trettio år, men fortfarande är en stor majoritet av svenskarna mentalt nära skog och mark. Hela 86 procent av de tillfrågade tycker att skyddade naturområden är avstressande miljöer.

  • 15. Gonzalez, Eduardo
    et al.
    Felipe-Lucia, Maria R.
    Bourgeois, Berenger
    Boz, Bruno
    Nilsson, Christer
    Umeå University, Faculty of Science and Technology, Department of Ecology and Environmental Sciences.
    Palmer, Grant
    Sher, Anna A.
    Integrative conservation of riparian zones2017In: Biological Conservation, ISSN 0006-3207, E-ISSN 1873-2917, Vol. 211, 20-29 p.Article in journal (Refereed)
    Abstract [en]

    Riparian zones are the interface between aquatic and terrestrial systems along inland watercourses. They have a disproportionate ecological role in the landscape considering their narrow extent, which makes them a good example of small natural features (sensu Hunter, 2017-in this issue). Characteristically, riparian zones increase species richness in the landscape and provide key services to society, such as soil fertility, water purification, and recreation. Despite the recognized importance of riparian zones for ecological, economic and social reasons, and the vast amount of scientific literature exploring measures for their conservation, current management is still failing at enabling a proper ecological functioning of these areas. The best practices for conservation of riparian zones have mostly focused on manipulating biotic and physical components (e.g. renaturalizing flow regimes, improving channel mobility, and controlling invasions of exotic ecosystem engineer species). However, these strategies face important technical, socio-economic, and legal constraints that require a more integrative approach for effective conservation. In this paper we summarize the main problems affecting riparian zones and their current management challenges. Following Hunter et al. (2017-in this issue), we review novel approaches to conservation of riparian zones, complementary to manipulating processes that reflect contemporary management and policy. These include (1) investing in environmental education for both local people and technical staff, (2) guaranteeing qualitative and long term inventories and monitoring, (3) establishing legislation and solutions to protect riparian zones, (4) framing economic activities in riparian zones under sustainable management, and (5) planning restoration of riparian zones at multiple and hierarchical spatio-temporal scales.

  • 16. Holt, Eva
    et al.
    Kocan, Anton
    Klanova, Jana
    Assefa, Anteneh
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Wiberg, Karin
    Spatiotemporal patterns and potential sources of polychlorinated biphenyl (PCB) contamination in Scots pine (Pinus sylvestris) needles from Europe2016In: Environmental science and pollution research international, ISSN 0944-1344, E-ISSN 1614-7499, Vol. 23, no 19, 19602-19612 p.Article in journal (Refereed)
    Abstract [en]

    Using pine needles as a bio-sampler of atmospheric contamination is a relatively cheap and easy method, particularly for remote sites. Therefore, pine needles have been used to monitor a range of semi-volatile contaminants in the air. In the present study, pine needles were used to monitor polychlorinated biphenyls (PCBs) in the air at sites with different land use types in Sweden (SW), Czech Republic (CZ), and Slovakia (SK). Spatiotemporal patterns in levels and congener profiles were investigated. Multivariate analysis was used to aid source identification. A comparison was also made between the profile of indicator PCBs (ind-PCBs-PCBs 28, 52, 101, 138, 153, and 180) in pine needles and those in active and passive air samplers. Concentrations in pine needles were 220-5100 ng kg(-1) (a(18)PCBs - ind-PCBs and dioxin-like PCBs (dl-PCBs)) and 0.045-1.7 ng toxic equivalent (TEQ) kg(-1) (dry weight (dw)). Thermal sources (e.g., waste incineration) were identified as important sources of PCBs in pine needles. Comparison of profiles in pine needles to active and passive air samplers showed a lesser contribution of lower molecular weight PCBs 28 and 52, as well as a greater contribution of higher molecular weight PCBs (e.g., 180) in pine needles. The dissimilarities in congener profiles were attributed to faster degradation of lower chlorinated congeners from the leaf surface or metabolism by the plant.

  • 17.
    Jørgensen, Dolly
    Umeå University, Faculty of Science and Technology, Department of Ecology and Environmental Sciences.
    Pigs and pollards: medieval insights for UK wood pasture restoration2013In: Sustainability, ISSN 2071-1050, E-ISSN 2071-1050, Vol. 5, no 2, 387-399 p.Article in journal (Refereed)
    Abstract [en]

    English wood pastures have become a target for ecological restoration, including the restoration of pollarded trees and grazing animals, although pigs have not been frequently incorporated into wood pasture restoration schemes. Because wood pastures are cultural landscapes, created through the interaction of natural processes and human practices, a historical perspective on wood pasture management practices has the potential to provide insights for modern restoration projects. Using a wide range of both written and artistic sources form the Middle Ages, this article argues that pigs were fed in wood pastures both during the mast season when acorns were available and at other times as grazing fields. Pollarded pedunculate oak (Quercus robur) likely dominated these sustainable cultural landscapes during the medieval period.

  • 18.
    Lie, Marit H.
    et al.
    Norwegian Univ Life Sci, Dept Ecol & Nat Resource Management, As, Norway.
    Josefsson, Torbjorn
    Umeå University, Faculty of Science and Technology, Department of Ecology and Environmental Sciences.
    Storaunet, Ken Olaf
    Norwegian Forest & Landscape Inst, As, Norway.
    Ohlson, Mikael
    Norwegian Univ Life Sci, Dept Ecol & Nat Resource Management, As, Norway.
    A refined view on the "Green lie'': Forest structure and composition succeeding early twentieth century selective logging in SE Norway2012In: Scandinavian Journal of Forest Research, ISSN 0282-7581, E-ISSN 1651-1891, Vol. 27, no 3, 270-284 p.Article in journal (Refereed)
    Abstract [en]

    Logging exceeded growth and timber trees were sparse in Norwegian forests in the early 1900s. Still, the forest canopy was lush green and characterised by large tree-crowns. This situation was referred to as the "Green lie'' and was advocated by foresters throughout Scandinavia as an argument in favour of forestry practices based on clear-felling. Here we examine effects of past selective loggings on forest structure and composition in a spruce forest landscape using dendroecology and historical records. Our results show that forests that were selectively logged up to the early 1900s could be structurally heterogeneous with multi-layered canopies, varying degree of openness and continuous presence of old trees across different spatial scales. Because the past forests were not clear-felled, a diverse forest structure in terms of tree species composition and age and diameter distribution was maintained over time, which could enable forest-dwelling species to persist during the early phase following the loggings in the past. This is in sharp contrast to the situation in most modern managed forest landscapes in Scandinavia. A better understanding of the link between loggings in the past- and present-day forest structure and diversity will contribute to rewarding discussions on forestry methods for the future.

  • 19. McIntosh, Christopher R
    et al.
    Shogren, Jason F
    Umeå University, Faculty of Social Sciences, Department of Economics.
    Dohlman, Erik
    Supply response to countercyclical payments and base acre updating under uncertainty: an experimental study2007In: American Journal of Agricultural Economics, ISSN 0002-9092, E-ISSN 1467-8276, Vol. 89, no 4, 1046-1057 p.Article in journal (Refereed)
    Abstract [en]

    We design an experiment to simulate how people make agricultural production decisions under three policy scenarios, each incorporating direct payments (DPs): (a) price uncertainty without countercyclical payments (CCPs); (b) price uncertainty with CCPs; and (c) price uncertainty, CCPs, and uncertainty regarding base acreage updating. Results are the CCP program and perceived possibility of future base updating created incentives for subjects to invest more in program (base) crops, despite payments being decoupled from current production decisions. Those choosing to reduce revenue risk by increasing plantings of base crops may face reduced incomes, suggesting the efficiency of crop markets may be diminished.

  • 20. Olsson, Håkan
    et al.
    Skånes, Helle
    Tulldahl, Michael
    Wikström, Sofia
    Kautsky, Hans
    Rydell, Bengt
    Årnfelt, Erik
    Eklöf, Jan
    Steinvall, Ove
    Flygburen laser och digitala bilder för kartering och övervakning av akvatisk och terrester miljö2014Report (Other academic)
  • 21. Parkhurst, Gregory M
    et al.
    Shogren, Jason F
    Umeå University, Faculty of Social Sciences, Department of Economics.
    Smart subsidies for conservation2008In: American Journal of Agricultural Economics, ISSN 0002-9092, E-ISSN 1467-8276, Vol. 90, no 5, 1192-1200 p.Article in journal (Refereed)
  • 22.
    Shogren, Jason F
    et al.
    Umeå University, Faculty of Social Sciences, Department of Economics.
    Stamland, Tommy
    Valuing lives saved from safer food: a cautionary tale revisited2007Conference paper (Other academic)
  • 23.
    Stål, Herman I.
    et al.
    Umeå University, Faculty of Social Sciences, Umeå School of Business and Economics (USBE), Business Administration.
    Bonnedahl, Karl J.
    Umeå University, Faculty of Social Sciences, Umeå School of Business and Economics (USBE), Business Administration.
    Eriksson, Jessica
    Umeå University, Faculty of Social Sciences, Umeå School of Business and Economics (USBE), Business Administration.
    Micro-level translation of greenhouse gas (GHG) reduction – policy meets industry in the Swedish agricultural sector2015In: Journal of Cleaner Production, ISSN 0959-6526, E-ISSN 1879-1786, Vol. 103, 629-639 p.Article in journal (Refereed)
    Abstract [en]

    Reducing greenhouse gas (GHG) emissions is an urgent challenge for mankind. However, as aggregate emissions continue to rise, necessary changes in industrial practices are lagging behind. The article addresses this discrepancy by exploring how the issue of GHG reduction is channeled from policy to industry, in one of the more GHG intensive sectors, agriculture. We adopt the translation perspective to analyze and discuss how the climate issue travels between contexts. Our study explores the activities involved as advisors, functioning as translating agents within Swedish agri-policy, inform producers about the issue of GHG reduction. The study sheds new light on the effectiveness of mitigation policy in promoting practice change and illustrates how translation is an analytical framework suitable for studying this within different industries.

  • 24.
    Su, Xiaolei
    et al.
    Umeå University, Faculty of Science and Technology, Department of Ecology and Environmental Sciences. Key Laboratory of Eco-Environments in Three Gorges Reservoir Region (Ministry of Education), Chongqing Key Laboratory of Plant Ecology and Resources in Three Gorges Reservoir Region, School of Life Sciences, Southwest University, Beibei, Chongqing 400715, PR China.
    Nilsson, Christer
    Umeå University, Faculty of Science and Technology, Department of Ecology and Environmental Sciences.
    Pilotto, Francesca
    Umeå University, Faculty of Science and Technology, Department of Ecology and Environmental Sciences.
    Liu, Songping
    Shi, Shaohua
    Zeng, Bo
    Soil erosion and deposition in the new shorelines of the Three Gorges Reservoir2017In: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 599, 1485-1492 p.Article in journal (Refereed)
    Abstract [en]

    During the last few decades, the construction of storage reservoirs worldwide has led to the formation of many new shorelines in former upland areas. After the formation of such shorelines, a dynamic phase of soil erosion and deposition follows. We explored the factors regulating soil dynatitics in the shorelines of the Three Gorges Reservoir (TGR) on the Yangtze River in China. We selected four study sites on the main stem and three on the tributaries in the upstream parts of the reservoir, and evaluated whether the sites close to the backwater tail (the point at which the river meets the reservoir) had more soil deposition than the sites far from the backwater tail. We also tested whether soil erosion differed between the main stem and the tributaries and across shorelines. We found that soil deposition in the new shorelines was higher close to the backwater tail and decreased downstream. Soil erosion was higher in the main stem than in the tributaries and higher at lower compared to higher shoreline altitudes. In the tributaries, erosion did not differ between higher and lower shoreline levels. Erosion increased with increasing fetch length, inundation duration and distance from the backwater tail, and decreased with increasing soil particle fineness. Our results provide a basis for identifying shorelines in need of restorative or protective measures.

  • 25. Terhivuo, Juhani
    et al.
    Saura, Anssi
    Umeå University, Faculty of Science and Technology, Department of Molecular Biology (Faculty of Science and Technology).
    Clone distribution of the earthworm Eiseniella tetraedra (Sav.) (Oligochaeta: Lumbricidae) across an altitudinal gradient on subarctic mountains of NW Europe2008In: Pedobiologia, ISSN 0031-4056, E-ISSN 1873-1511, Vol. 51, no 5-6, 375-384 p.Article in journal (Refereed)
    Abstract [en]

    In earlier studies, we have shown that clone diversity of the parthenogenetic earthworm Eiseniella tetraedra increases from the upper reaches of rivers in northern Sweden towards their mouths. Now we survey brooks in the Scandes Mountains in the watershed between Sweden and Norway where major rivers originate. Using starch get enzyme electrophoresis, we found 37 clones in a total catch of 379 individuals from six mountains. The most abundant clone made up 48.3% of the individuals collected. It was present on most mountains and was found at different elevations. In comparison with other clones it may represent a general-purpose genotype adapted to environmental conditions ranging from alpine through to subalpine to boreal habitats in the mountains. Diversity of clone assemblages decreased with increasing elevation. On four mountains, one to two clones were found at higher elevations. Passive downstream dispersal of E. tetraedra propagules from wider areas of the mountains was responsible for the more diverse clone pools in the tower reaches of the brooks (i.e., "small rivers behave like large ones"). Two clone groups, which deviated from the norm clone in their number of enzyme variants, were evenly distributed among different elevations. Therefore, we could not correlate genotype differences (i.e., adaptation of clones to mountain elevations). Clone pool similarities among the mountains were tow on average (range 0-58%) but in a cluster of four mountains, similarities varied from 46% to 58%. Clone pool similarities between different elevations of the same mountain ranged from 27% to 83%. One mountain brook was sampled over 3 years to assess clone turnover. Only the norm clone was found in upstream habitats but it and three other clones were recorded downstream in at least 2 years. Ten clones were found once in the latter habitat as well.

  • 26.
    Vestergren, Johan
    et al.
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Vincent, Andrea G
    Umeå University, Faculty of Science and Technology, Department of Ecology and Environmental Sciences.
    Jansson, Mats
    Umeå University, Faculty of Science and Technology, Department of Ecology and Environmental Sciences.
    Persson, Per
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Istedt, Ulrik
    Department of Forest Ecology & Management, SLU, Umeå, Sweden.
    Gröbner, Gerhard
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Giesler, Reiner
    Umeå University, Faculty of Science and Technology, Department of Ecology and Environmental Sciences.
    Schleucher, Jürgen
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    High resolution characterization of organic phosphorus in soil extracts using 2D 1H-31P NMR correlation spectroscopy2012In: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 46, no 7, 3950-3956 p.Article in journal (Refereed)
    Abstract [en]

    Organic phosphorus (P) compounds represent a major component of soil P in many soils and are key sources of P for microbes and plants. Solution NMR (nuclear magnetic resonance spectroscopy) is a powerful technique for characterizing organic P species. However, <sup>31</sup>P NMR spectra are often complicated by overlapping peaks, which hampers identification and quantification of the numerous P species present in soils. Overlap is often exacerbated by the presence of paramagnetic metal ions, even if they are in complexes with EDTA following NaOH/EDTA extraction. By removing paramagnetic impurities using a new precipitation protocol, we achieved a dramatic improvement in spectral resolution. Furthermore, the obtained reduction in line widths enabled the use of multi-dimensional NMR methods to resolve overlapping <sup>31</sup>P signals. Using the new protocol on samples from two boreal humus soils with different Fe contents, two-dimensional <sup>1</sup>H-<sup>31</sup>P correlation spectra allowed unambiguous identification of a large number of P species based on their <sup>31</sup>P and <sup>1</sup>H chemical shifts and their characteristic coupling patterns, which would not have been possible using previous protocols. This approach can be used to identify organic P species in samples from both terrestrial and aquatic environments, increasing our understanding of organic P biogeochemistry.

  • 27. Whitty, Kevin
    et al.
    Backman, Rainer
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics, Energy Technology and Thermal Process Chemistry.
    Hupa, Mikko
    Influence of pressure on pyrolysis of black liquor: 1. Swelling2008In: Bioresource Technology, ISSN 0960-8524, E-ISSN 1873-2976, Vol. 99, no 3, 663-670 p.Article in journal (Refereed)
    Abstract [en]

    This is the first of two papers concerning the behavior of black liquor during pyrolysis under pressurized conditions. Two industrial kraft liquors were pyrolyzed in a laboratory-scale pressurized single particle reactor and a pressurized grid heater at temperatures ranging from 650 to 1100 degrees C and at pressures between 1 and 20 bar. The dimensions of the chars produced were measured and the specific swollen volume was calculated. Swelling decreased roughly logarithmically over the pressure range 1-20 bar. An expression is developed to predict the specific swollen volume at elevated pressure when the volume at 1 bar is known. The bulk density of the char increased with pressure, indicating that liquors will be entrained less easily at higher pressures.

  • 28. Whitty, Kevin
    et al.
    Kullberg, Mika
    Sorvari, Vesa
    Backman, Rainer
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics, Energy Technology and Thermal Process Chemistry.
    Hupa, Mikko
    Influence of pressure on pyrolysis of black liquor: 2. Char yields and component release2008In: Bioresource Technology, ISSN 0960-8524, E-ISSN 1873-2976, Vol. 99, no 3, 671-679 p.Article in journal (Refereed)
    Abstract [en]

    This is the second in a series of papers concerning the behavior of black liquor during pyrolysis at elevated pressures. Two industrial black liquors were pyrolyzed under pressurized conditions in two laboratory-scale devices, a pressurized single-particle reactor and a pressurized grid heater. Temperatures ranging between 650 and 1100 degrees C and pressures in the range 1-20 bar were studied. Char yields were calculated and based on analysis of some of the chars the fate of carbon, sodium, potassium and sulfur was determined as a function of pyrolysis pressure. At temperatures below 800 degrees C little variation in char yield was observed at different pressures. At higher temperatures char yield increased with pressure due to slower decomposition of sodium carbonate. For the same reason, sodium release decreased with pressure. Sulfur release, however, increased with pressure primarily because there was less opportunity for its capture in the less-swollen chars.

1 - 28 of 28
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