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  • 1. Adolf, Carole
    et al.
    Wunderle, Stefan
    Colombaroli, Daniele
    Weber, Helga
    Gobet, Erika
    Heiri, Oliver
    van Leeuwen, Jacqueline F. N.
    Bigler, Christian
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Connor, Simon E.
    Galka, Mariusz
    La Mantia, Tommaso
    Makhortykh, Sergey
    Svitavska-Svobodova, Helena
    Vanniere, Boris
    Tinner, Willy
    The sedimentary and remote-sensing reflection of biomass burning in Europe2018Ingår i: Global Ecology and Biogeography, ISSN 1466-822X, E-ISSN 1466-8238, Vol. 27, nr 2, s. 199-212Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Aim: We provide the first European-scale geospatial training set relating the charcoal signal in surface lake sediments to fire parameters (number, intensity and area) recorded by satellite moderate resolution imaging spectroradiometer (MODIS) sensors. Our calibration is intended for quantitative reconstructions of key fire-regime parameters by using sediment sequences of microscopic (MIC from pollen slides, particles 10-500 mu m) and macroscopic charcoal (MAC from sieves, particles > 100 mu m). Location: North-south and east-west transects across Europe, covering the mediterranean, temperate, alpine, boreal and steppe biomes. Time period: Lake sediments and MODIS active fire and burned area products were collected for the years 2012-2015. Methods: Cylinder sediment traps were installed in lakes to annually collect charcoal particles in sediments. We quantitatively assessed the relationships between MIC and MAC influx (particles/cm(2)/year) and the MODIS-derived products to identify source areas of charcoal and the extent to which lake-sediment charcoal is linked to fire parameters across the continent. Results: Source area of sedimentary charcoal was estimated to a 40-km radius around sites for both MIC and MAC particles. Fires occurred in grasslands and in forests, with grass morphotypes of MAC accurately reflecting the burned fuel-type. Despite the lack of local fires around the sites, MAC influx levels reached those reported for local fires. Both MIC and MAC showed strong and highly significant relationships with the MODIS-derived fire parameters, as well as with climatic variation along a latitudinal temperature gradient. Main conclusions: MIC and MAC are suited to quantitatively reconstructing fire number and fire intensity on a regional scale. However, burned area may only be estimated using MAC. Local fires may be identified by using several lines of evidence, e.g. analysis of large particles (> 600 mu m), magnetic susceptibility and sedimentological data. Our results offer new insights and applications to quantitatively reconstruct fires and to interpret available sedimentary charcoal records.

  • 2. Akhter, Shirin
    et al.
    Kretzschmar, Warren W.
    Nordal, Veronika
    Delhomme, Nicolas
    Street, Nathaniel
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC).
    Nilsson, Ove
    Emanuelsson, Olof
    Sundström, Jens F.
    Integrative analysis of three RNA sequencing methods identifies mutually exclusive exons of MADS-box isoforms during early bud development in Picea abies2018Ingår i: Frontiers in Plant Science, ISSN 1664-462X, E-ISSN 1664-462X, Vol. 9, artikel-id 1625Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Recent efforts to sequence the genomes and transcriptomes of several gymnosperm species have revealed an increased complexity in certain gene families in gymnosperms as compared to angiosperms. One example of this is the gymnosperm sister Glade to angiosperm TM3-like MADS-box genes, which at least in the conifer lineage has expanded in number of genes. We have previously identified a member of this subclade, the conifer gene DEFICIENS AGAMOUS LIKE 19 (DAL19), as being specifically upregulated in cone-setting shoots. Here, we show through Sanger sequencing of mRNA-derived cDNA and mapping to assembled conifer genomic sequences that DAL19 produces six mature mRNA splice variants in Picea abies. These splice variants use alternate first and last exons, while their four central exons constitute a core region present in all six transcripts. Thus, they are likely to be transcript isoforms. Quantitative Real-Time PCR revealed that two mutually exclusive first DAL19 exons are differentially expressed across meristems that will form either male or female cones, or vegetative shoots. Furthermore, mRNA in situ hybridization revealed that two mutually exclusive last DAL19 exons were expressed in a cell-specific pattern within bud meristems. Based on these findings in DAL19, we developed a sensitive approach to transcript isoform assembly from short-read sequencing of mRNA. We applied this method to 42 putative MADS-box core regions in P abies, from which we assembled 1084 putative transcripts. We manually curated these transcripts to arrive at 933 assembled transcript isoforms of 38 putative MADS-box genes. 152 of these isoforms, which we assign to 28 putative MADS-box genes, were differentially expressed across eight female, male, and vegetative buds. We further provide evidence of the expression of 16 out of the 38 putative MADS-box genes by mapping PacBio Iso-Seq circular consensus reads derived from pooled sample sequencing to assembled transcripts. In summary, our analyses reveal the use of mutually exclusive exons of MADS-box gene isoforms during early bud development in P. abies, and we find that the large number of identified MADS-box transcripts in P. abies results not only from expansion of the gene family through gene duplication events but also from the generation of numerous splice variants.

  • 3.
    Almstedt, Åsa
    et al.
    Umeå universitet, Samhällsvetenskapliga fakulteten, Institutionen för geografi och ekonomisk historia.
    Keskitalo, E. Carina H.
    Umeå universitet, Samhällsvetenskapliga fakulteten, Institutionen för geografi och ekonomisk historia.
    The role of market measures in forest governance: the example of forest certification in boreal forests2017Ingår i: CAB Reviews, ISSN 1749-8848, Vol. 12, nr 11, s. 1-11Artikel i tidskrift (Refereegranskat)
  • 4.
    Almstedt, Åsa
    et al.
    Umeå universitet, Samhällsvetenskapliga fakulteten, Institutionen för geografi och ekonomisk historia, Kulturgeografi.
    Reed, Maureen G.
    Introducing a framework for good and adaptive governance: an application to fire management planning in Canada's boreal forest2013Ingår i: Forestry Chronicle, ISSN 0015-7546, Vol. 89, nr 5, s. 664-674Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Planning for and managing disturbances in protected areas requires governance arrangements that are both adaptive to changing conditions and effective in dealing with multiple challenges. This paper presents a framework composed of principles and criteria of good and adaptive governance that pays attention to inclusiveness, responsibility, fairness, strategic vision, performance orientation, and adaptiveness. The framework was empirically tested on fire management planning in Prince Albert National Park, Saskatchewan, Canada, involving interactions between Parks Canada and Saskatchewan Environment. Our results suggest that while the principle of performance orientation was upheld, principles such as inclusiveness and adaptiveness were only partially supported. Additional testing beyond fire management planning can help determine the utility of the framework for other environmental management situations.

  • 5. Andersson, Elias
    et al.
    Keskitalo, E. Carina H.
    Umeå universitet, Samhällsvetenskapliga fakulteten, Institutionen för geografi och ekonomisk historia.
    Adaptation to climate change?: Why business-as-usual remains the logical choice in Swedish forestry2018Ingår i: Global Environmental Change, ISSN 0959-3780, E-ISSN 1872-9495, Vol. 48, s. 76-85Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The two latest IPCC assessment reports have concluded that knowledge is not sufficient for inducing action on climate change. This study problematizes the issue of going beyond business-as-usual through a study of the forestry sector in Sweden, which is a large economic sector and could be expected to be an early adapter, given that newly planted forest may stand some 70-90 years into the future. Therefore resources, economic motivation in the longer term and environmental foundations for early adaptation action could be expected to exist. This study draws upon the Foucauldian conceptualization of governmentality to explain the particular institutional logics that nevertheless lead to business-as-usual arguments dominating discussion on adaptation in the case of Swedish forestry. The study emphasizes that adaptation must be seen as steered and limited by existing institutional, social system logics, rather than by externally defined "rational" motivations. Efforts on adaptation to climate change must thus be considered in relation to, and seek to change, existing institutionally based motivational and incentive structures, and must thus be conceived through social rather than environmental logics. In fact, social logics may even define the types of actions that may be regarded as adaptations.

  • 6. Andersson, Elias
    et al.
    Keskitalo, E Carina H
    Umeå universitet, Samhällsvetenskapliga fakulteten, Institutionen för geografi.
    Service logics and strategies of Swedish forestry in the structural shifts of forest ownership: challenging the "old" and shaping the "new"2019Ingår i: Scandinavian Journal of Forest Research, ISSN 0282-7581, E-ISSN 1651-1891Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Sweden is one of the most forested countries in Europe, and it has one of the highest shares of productive forest. Production in forestry is largely reliant on the private non-industrial forest owners, who own half of the forest land. As in many countries, however, forest ownership is changing towards a higher extent of urban, female or non-forestry-background owners. This poses a challenge for the forestry services sector, mainly forest owners' associations and companies, but also broadly the sector at large. By exploring the sales and marketing processes, this paper analyses the service logics and strategies of Swedish forestry under changing forest ownership, drawing on an interview study covering all the large actors in the Swedish forestry sector. The study illustrates an increased focus of forestry organizations on services from a strategic and managerial perspective, in customer-oriented relationship development and in value creation and sales processes, specifically in order to manage "new" forest owners and the demand of forest industries. The results highlight the domination of service logics associated with timber production and the challenges for the service market and the provision of diversified services to forest owners.

  • 7. Andersson, Elias
    et al.
    Keskitalo, E Carina H
    Umeå universitet, Samhällsvetenskapliga fakulteten, Institutionen för geografi och ekonomisk historia.
    Bergstén, Sabina
    Umeå universitet, Samhällsvetenskapliga fakulteten, Institutionen för geografi och ekonomisk historia.
    In the eye of the storm: adaptation logics of forest owners in management and planning in Swedish areas2018Ingår i: Scandinavian Journal of Forest Research, ISSN 0282-7581, E-ISSN 1651-1891, Vol. 33, nr 8, s. 800-808Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    With a changing climate, storm and wind throw is becoming an increasing risk to forest. However, Swedish forest management practices have so far involved relatively little consideration of adaptation to climate change. This study examined resistance and alternatives to business as usual forest management, drawing upon material obtained in interviews with individual forest owners who spontaneously identified and discussed storm and wind throw as a risk to their forest. They thereby expressed a logic differing from that of the forest industry in Sweden, which has largely normalised storm risk rather than considering it in climate change adaptation work. The present analysis illustrates the broad and largely concerned position of individual forest owners, in contrast with a more established industry position on storm as an accepted and existing risk. Overall, the study highlights the diversity, agency and power relations within Swedish forestry and the forested landscape - aspects that are vital to better understanding processes relevant to forest and climate change adaptation.

  • 8.
    Andersson, Elias
    et al.
    Department of Forest Resource Management, Swedish University of Agricultural Sciences, Umeå, Sweden.
    Keskitalo, E. Carina H.
    Umeå universitet, Samhällsvetenskapliga fakulteten, Institutionen för geografi och ekonomisk historia. Department of Forest Resource Management, Swedish University of Agricultural Sciences, Umeå, Sweden.
    Lawrence, Anna
    Adaptation to climate change in forestry: a perspective on forest ownership and adaptation responses2017Ingår i: Forests, ISSN 1999-4907, E-ISSN 1999-4907, Vol. 8, nr 12, artikel-id 493Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Adaptation to climate change has often been discussed from the perspectives of social vulnerability and community vulnerability, recognising that characteristics at local level will influence the particular adaptations undertaken. However, the extent to which national-level systemic factors influence and shape measures defined as adaptations has seldom been recognised. Focusing on adaptation to climate change in forestry, this study uses the example of two countries in the northern hemisphere with different forest ownership structures, forestry industry and traditions: Sweden, with strong private, non-industrial ownership, dominant forest industry and long forestry traditions; and Scotland, with forest ownership dominated by large estates and investment forestry based on plantations of exotic conifer species. The study shows how adaptation to climate change is structurally embedded and conditioned, which has resulted in specific challenges and constraints for different groups of forest owners within these two different contexts. This produces a specific set of political spaces and policy tools by rendering climate change in relation to forestry manageable, negotiable and practical/logical in specific ways. It is recommended that the focus of future work on climate-related issues and development of adaptation measures and policy should not be primarily on climate-related factors, but on institutional analysis of structural factors and logics in target sectors, in order to critically explore concepts of agency and power within these processes.

  • 9.
    Androsiuk, P.
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. University of Warmia & Mazury, Poland.
    Shimono, A.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Westin, J.
    Lindgren, D.
    Fries, A.
    Wang, X. -R
    Genetic status of Norway spruce (Picea abies) breeding populations for northern Sweden2013Ingår i: Silvae Genetica, ISSN 0037-5349, Vol. 62, nr 3, s. 127-136Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Efficient use of any breeding resources requires a good understanding of the genetic value of the founder breeding materials for predicting the gain and diversity in future generations. This study evaluates the distribution of genetic variation and level of relatedness among and within nine breeding populations of Norway spruce for Northern Sweden using nuclear microsatellite markers. A sample set of 456 individuals selected from 140 stands were genotyped with, 15 SSR loci. Over all loci each individual was identified with unique multilocus genotype. High genetic diversity (average H-e=0.820) and low population differentiation (F-ST = 0.0087) characterized this material. Although low in F-ST, the two northernmost populations were clustered as a distinct group diverged from the central populations. The population differentiation pattern corresponds well with the post glacial migration history of Norway spruce and the current gene flow and human activity in the region. The average inbreeding coefficient was 0.084 after removal loci with high frequency of null alleles. The estimated relatedness of the trees gathered in the breeding populations was very low (average kinship coefficient 0.0077) and not structured. The high genetic variation and low and not structured relatedness between individuals found in the breeding populations confirm that the Norway spruce breeding stock for northern Sweden represent valuable genetic resources for both long-term breeding and conservation programs.

  • 10. Anugwom, Ikenna
    et al.
    Maki-Arvela, Paivi
    Virtanen, Pasi
    Willfor, Stefan
    Damlin, Pia
    Hedenström, Mattias
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Mikkola, Jyri-Pekka
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Treating birch wood with a switchable 1,8-diazabicyclo-[5.4.0]-undec-7-ene-glycerol carbonate ionic liquid2012Ingår i: Holzforschung, ISSN 0018-3830, E-ISSN 1437-434X, Vol. 66, nr 7, s. 809-815Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The suitability of a new switchable ionic liquid (SIL) has been investigated as a solvent for fractionation of lignocellulosic materials. SIL was prepared from inexpensive chemicals, e. g., glycerol, CO2, and 1,8-diazabicyclo-[5.4.0]-undec-7-ene (DBU). Fresh Nordic birch wood (B. pendula) was treated with the SIL for a time period of 1-5 days at 100 degrees C and under atmospheric pressure. Upon SIL treatment, at best, 57 % of the hemicelluloses were dissolved and 50 % of lignins were dissolved from the native birch. The slightly fibrillated SIL treated chips contained about 55 % cellulose. Up to 76 % of the recovered species removed from the spent SIL liquor was originating from hemicelluloses, mainly from xylan. The spent SILs were reused for fresh wood dissolution in four consecutive cycles and each time the wood dissolution efficiency was similar. SILs could offer affordable (easy-to-synthesize) solvent systems for partial elimination of hemicelluloses and lignin from wood. SILs can also be prepared in-situ and on-site.

  • 11.
    Athanassiadis, Dimitris
    et al.
    Dept. of Forest Resource Management, Swedish University of Agricultural Sciences.
    Bergström, Dan
    Hellström, Thomas
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för datavetenskap.
    Lindroos, Ola
    Dept. of Forest Resource Management, Swedish University of Agricultural Sciences.
    Nordfjell, Tomas
    Dept. of Forest Resource Management, Swedish University of Agricultural Sciences.
    Ringdahl, Ola
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för datavetenskap.
    Path tracking for autonomous forwarders in forest terrain2010Ingår i: Precision Forestry Symposium: developments in Precision Forestry since 2006 / [ed] Ackerman P A, Ham H, & Lu C, 2010, s. 42-43Konferensbidrag (Refereegranskat)
  • 12. Ausin, Israel
    et al.
    Feng, Suhua
    Yu, Chaowei
    Liu, Wanlu
    Kuo, Hsuan Yu
    Jacobsen, Elise L.
    Zhai, Jixian
    Gallego-Bartolome, Javier
    Wang, Lin
    Egertsdotter, Ulrika
    Street, Nathaniel R.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC). Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik.
    Jacobsen, Steven E.
    Wang, Haifeng
    DNA methylome of the 20-gigabase Norway spruce genome2016Ingår i: Proceedings of the National Academy of Sciences of the United States of America, ISSN 0027-8424, E-ISSN 1091-6490, Vol. 113, nr 50, s. E8106-E8113Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    DNA methylation plays important roles in many biological processes, such as silencing of transposable elements, imprinting, and regulating gene expression. Many studies of DNA methylation have shown its essential roles in angiosperms (flowering plants). However, few studies have examined the roles and patterns of DNA methylation in gymnosperms. Here, we present genome-wide high coverage single-base resolution methylation maps of Norway spruce (Picea abies) from both needles and somatic embryogenesis culture cells via whole genome bisulfite sequencing. On average, DNA methylation levels of CG and CHG of Norway spruce were higher than most other plants studied. CHH methylation was found at a relatively low level; however, at least one copy of most of the RNA-directed DNA methylation pathway genes was found in Norway spruce, and CHH methylation was correlated with levels of siRNAs. In comparison with needles, somatic embryogenesis culture cells that are used for clonally propagating spruce trees showed lower levels of CG and CHG methylation but higher level of CHH methylation, suggesting that like in other species, these culture cells show abnormal methylation patterns.

  • 13.
    Bandau, Franziska
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC).
    Importance of tannins for responses of aspen to anthropogenic nitrogen enrichment2016Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [sv]

    Boreala skogar är ofta mycket kväve (N) begränsade. Men mänskliga aktiviteter leder till ökad N tillförsel i dessa ekosystem, både genom depostition av N från atmosfären och skogsgödsling. N-tillförsel i boreala skogar kan främja netto primärproduktionen men även leda till ökade skador från naturliga fiender (herbivorer och patogener) samt skiftningar i växtartsammansättning. Genetisk mångfald har föreslagits som en viktig mekanism för att främja en växtarts stabilitet inom samhällen som upplever miljöförändringar. Inom varje växtpopulation kan specifika egenskaper (t.ex. tillväxt och försvar) varierar kraftigt mellan individer och en större variation i egenskaper kan öka chanserna för att åtminstone några individer från en population överlever ifall miljöförhållandena förändras. En aspekt av växtkemi som i hög grad kan variera mellan olika genotyper (GT) är bladens kondenserade tanniner (KT). Dessa sekundära metaboliter har föreslagits påverka växtens prestationsförmåga på många sätt, t.ex. genom att påverka tillväxt, interaktioner mellan växter och herbivorer eller patogener och genom att påverka förna nedbrytning, och följaktligen återbördandet av näringsämnen till kretsloppet. För att undersöka hur genotypiska variation i KT produktion kan påverka de effekter som antopogent N kan ha på växtens prestationsförmåga och förna nedbrytning, utförde jag en serie experiment. Jag studerade olika asp (Populus tremula) GT med olika förmåga att producera KT (låg- och hög-tannin producenter). Växterna odlades i tre olika N förhållanden, som representerade ambient N nivå (+0 kg ha-1), atmosfärisk N deposition = låg nivå (+15 kg ha-1), och skogsgödsling = hög nivå (150 kg ha‑1). Dessa GT etablerades i en fält-liknande miljö där naturliga fiender uteslutits och i ett fält där naturliga fiender var närvarande. I mina första två studierna undersökte jag vävnadskemi och växternas prestationsförmåga i de båda miljöerna. Jag observerade att KT nivåerna sjönk till följd av N‑tillsats i den fiende-fria miljön (studie I), men ökade med N-tillsats ifall fiender var närvarande (studie II). Dessa motsatta reaktioner på N-tillsats kan förklaras av skillnader i N-tillgång mellan de två odlingsplatserna eller genom ökad KT produktion som respons på angrepp. Skador orsakade av herbivorer och patogener ökade generellt till följd av N‑tillsats och var högre i låg-tannin än i hög‑tannin producerande GT oavsett N‑förhållande. Tillväxten hos växter från högtannin GT begränsades i ambient- och låg N-tillsats förhållanden, troligen på grund av att avvägning mellan tillväxt och försvar förskjutits emot försvar. Den begränsade tillväxten i hög-tannin växter minskade om stora mängder N tillsattes (studie I och II) och om antalet fiender var tillräckligt högt så att nyttan av försvaret kunde uppväga kostnaderna för försvarsproduktionen (studie II). Trots dessa generella respons hos låg- och hög-tannin GT till följd av N‑tillsats observerade jag även ett antal individuella respons hos GT som i vissa fall var orelaterade till växters förmåga att producera KT. I studie III undersöktes genuttrycksnivåer och fenolinnehåll i blad från växter som odladats i en miljö där naturliga fiender exkluderats. Denna studie visade att fenylpropanoidsyntesvägen (FPV) regleras genom kontroll av många av de undersökta FPV-generna. Dessutom var FPV genuttryck högre i hög-tannin GT än i låg-tannin GT, särskilt vid ambient N. Vid låg N-tillsats minskade genuttrycket av FPV-gener i både låg- och hög-tannin producenter, medan hög N-tillgång ledde till att gener i början och slutet av FPV uppreglerades och till att skillnaderna mellan tannin grupperna försvann. Dessutom visade studien att de separata fenol-poolerna ofta var okorrelerade med varandra och att fenol-poolerna bara till viss del var korrelerade med KT produktion och FPV-genutryck. I studie IV undersökte jag nedbrytningshastigheten för förnan från fältodlade aspar. Jag upptäckte att N-tillsats generellt minskade viktförlusten men att det fanns en betydande genetisk variation mellan GT och att dessa även var olika mottagliga för tillsatt N. Studie IV visade vidare att KT endast hade en svag effekt på nedbrytning och att andra egenskaper såsom specifik bladyta och lignin:N ratio kunde bättre förklara den genotypiska skillnaden i viktförlust. Dessutom orsakade N‑tillsats en förskjutning av vilka egenskaper som mest påverkade förnans nedbrytningshastighet. Sammanfattningsvis visar mina studier på vikten av genetisk mångfald för att främja växtartens stabilitet i miljöer som upplever antropogena förändringar.

  • 14.
    Barthelemy, Hélène
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Dorrepaal, Ellen
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Olofsson, Johan
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Defoliation of a grass is mediated by the positive effect of dung deposition, moss removal and enhanced soil nutrient contents: results from a reindeer grazing simulation experiment2019Ingår i: Oikos, ISSN 0030-1299, E-ISSN 1600-0706, Vol. 128, nr 10, s. 1515-1524Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Herbivory is one of the key drivers shaping plant community dynamics. Herbivores can strongly influence plant productivity directly through defoliation and the return of nutrients in the form of dung and urine, but also indirectly by reducing the abundance of neighbouring plants and inducing changes in soil processes. However, the relative importance of these processes is poorly understood. We, therefore, established a common garden experiment to study plant responses to defoliation, dung addition, moss cover, and the soil legacy of reindeer grazing. We used an arctic tundra grazed by reindeer as our study system, and Festuca ovina, a common grazing-tolerant grass species as the model species. The soil legacy of reindeer grazing had the strongest effect on plants, and resulted in higher growth in soils originating from previously heavily-grazed sites. Defoliation also had a strong effect and reduced shoot and root growth and nutrient uptake. Plants did not fully compensate for the tissue lost due to defoliation, even when nutrient availability was high. In contrast, defoliation enhanced plant nitrogen concentrations. Dung addition increased plant production, nitrogen concentrations and nutrient uptake, although the effect was fairly small. Mosses also had a positive effect on aboveground plant production as long as the plants were not defoliated. The presence of a thick moss layer reduced plant growth following defoliation. This study demonstrates that grasses, even though they suffer from defoliation, can tolerate high densities of herbivores when all aspects of herbivores on ecosystems are taken into account. Our results further show that the positive effect of herbivores on plant growth via changes in soil properties is essential for plants to cope with a high grazing pressure. The strong effect of the soil legacy of reindeer grazing reveals that herbivores can have long-lasting effects on plant productivity and ecosystem functioning after grazing has ceased.

  • 15.
    Beland Lindahl, Karin
    et al.
    Luleå tekniska universitet.
    Sténs, Anna
    Umeå universitet, Humanistiska fakulteten, Institutionen för idé- och samhällsstudier.
    Sandström, Camilla
    Umeå universitet, Samhällsvetenskapliga fakulteten, Statsvetenskapliga institutionen.
    Johansson, Johanna
    Umeå universitet, Samhällsvetenskapliga fakulteten, Statsvetenskapliga institutionen.
    Lidskog, Rolf
    Örebro universitet.
    Ranius, Thomas
    Sveriges lantbruksuniversitet, SLU, Uppsala, Sweden.
    Roberge, Jean-Michel
    Sveriges lantbruksuniversitet, SLU, Umeå, Sweden.
    The Swedish forestry model: more of everything?2017Ingår i: Forest Policy and Economics, ISSN 1389-9341, E-ISSN 1872-7050, Vol. 77, s. 44-55Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    "The Swedish forestry model" refers to the forest regime that evolved following the 1993 revision of the Swedish Forestry Act. It is key to Swedish forest politics and used to capture the essence of a sustainable way of managing forests. However, the ideas, institutions and practices comprising the model have not been comprehensively analyzed previously. Addressing this knowledge gap, we use frame analysis and a Pathways approach to investigate the underlying governance model, focusing on the way policy problems are addressed, goals, implementation procedures, outcomes and the resulting pathways to sustainability. We suggest that the institutionally embedded response to pressing sustainability challenges and increasing demands is expansion, inclusion and integration: more of everything. The more-of-everything pathway is influenced by ideas of ecological modernization and the optimistic view that existing resources can be increased. Our findings suggest that in effect it prioritizes the economic dimension of sustainability. While broadening out policy formulation it closes down the range of alternative outputs, a shortcoming that hampers its capacity to respond to current sustainability challenges. Consequently, there is a need for a broad public debate regarding not only the role of forests in future society, but also the operationalization of sustainable development.

  • 16. Berg, B.
    et al.
    Kjonaas, O. J.
    Johansson, M. -B
    Erhagen, Björn
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Åkerblom, S.
    Late stage pine litter decomposition: Relationship to litter N, Mn, and acid unhydrolyzable residue (AUR) concentrations and climatic factors2015Ingår i: Forest Ecology and Management, ISSN 0378-1127, E-ISSN 1872-7042, Vol. 358, s. 41-47Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The aim of this paper is to evaluate relationships between decomposition rates of Scots pine (Pinus sylvestris) and lodgepole pine (Pinus contorta var. contorta) needle litter in the late stage of decomposition (>30% accumulated mass loss), and the progressively changing concentrations of manganese (Mn), nitrogen (N), and acid unhydrolyzable residue (AUR), as well as mean annual temperature (MAT) and mean annual precipitation (MAP). Using available long-term decomposition studies on pine needle litter in a climate gradient in Sweden, we calculated annual mass loss and related to concentrations of Mn, N, and AUR at the start of each one-year period as well as to MAT and MAP. We investigated these relationships for (i) all data on annual mass loss combined and (ii) annual mass loss for five different decomposition categories as defined by accumulated mass loss. We found highly significant, negative, and dominant relationships between annual mass loss and N (R-2 = 0.39) and AUR (R-2 = 0.39), a slight but significant positive relationship to Mn (R-2 = 0.08) and a significant negative relationship to MAT (R-2 = 0.06). The relationships were dynamic, and changed with accumulated mass loss. The rate-dampening effect of N decreased to be a rate-enhancing effect at c. 60-80% accumulated mass loss. A similar trend was found for AUR, becoming rate-enhancing at 70-80% accumulated mass loss. For Scots pine needle litter the effect of MAT on mass loss decreased with increasing accumulated mass loss and changed to a rate-dampening effect at c. 50-70% accumulated mass loss. Mn showed a stimulating effect on mass loss rate in all categories whereas MAP showed no effect in this mainly boreal climatic gradient. The current approach indicates a method for detailed studies of rate-regulating factors for litter decomposition.

  • 17. Berg, Björn
    et al.
    Erhagen, Björn
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Johansson, Maj-Britt
    Nilsson, Mats
    Stendahl, Johan
    Trum, Florence
    Vesterdal, Lars
    Manganese in the litter fall-forest floor continuum of boreal and temperate pine and spruce forest ecosystems: A review2015Ingår i: Forest Ecology and Management, ISSN 0378-1127, E-ISSN 1872-7042, Vol. 358, s. 248-260Artikel, forskningsöversikt (Refereegranskat)
    Abstract [en]

    We have reviewed the literature on the role of manganese (Mn) in the litter fall-to-humus subsystem. Available data gives a focus on North European coniferous forests. Manganese concentrations in pine (Pinus spp.) foliar litter are highly variable both spatially and temporally within the same litter species and for the genus Pinus we found a range from 0.03 to 3.7 mg g(-1). Concentrations were related negatively to site mean annual temperature (MAT) and annual actual evapotranspiration (AET) for pine species litter but not for that of Norway spruce (Picea abies) as a single species. Combined data for several species showed a highly significant relationship to MAT. Manganese peroxidase is an Mn-dependent enzyme, found in white-rot fungi, essential for the degradation of lignin and ligninlike compounds. The decomposition rates of lignified litter tissue (late phase) is positively related to the litter's Mn concentration. Further, the Mn concentration is positively related to the limit value for decomposition - the higher the Mn concentration the smaller the stable litter fraction. Manganese release from decomposing litter appears at least in part to be species related. Thus was release from pine needle litter significantly faster (p < 0.001) than that from the Mn-richer litter of Norway spruce. Over Northern Europe concentrations of total Mn in mor humus as well as extractable Mn in the mineral soil increase with decreasing MAT and over a climatic gradient the Mn concentrations in Norway spruce mor increase more with decreasing MAT than in a gradient with Scots pine. Higher Mn concentrations in humus appear to decrease its stability and result in a higher release of carbon dioxide (CO2) and dissolved organic carbon (DOC). We conclude that this may explain (i) the lower amount of carbon (C) in mor layers under Norway spruce as compared to Scots pine as well as the higher amount of C in mineral soil under spruce. The increase in nitrogen (N) concentration in humus, following N fertilization resulted in a decrease in that of Mn. We have found four cases - empirical - with negative interaction between Mn and N; (i) in pine foliar litter fall concentrations of Mn decrease with site MAT whereas those of N increase, (ii) in decomposing late-stage litter with N retarding and Mn stimulating decomposition, (iii) for the stable phase, limit values are related negatively to N and positively to Mn, and (iv) Mn concentrations in humus decrease with MAT whereas those of N increase. (C) 2015 Elsevier B.V. All rights reserved.

  • 18.
    Berhe, Leakemariam
    et al.
    Umeå universitet, Samhällsvetenskaplig fakultet, Statistik.
    Arnoldsson, Göran
    Umeå universitet, Samhällsvetenskaplig fakultet, Statistik.
    Tree taper models for Cupressus lusitanica plantations in Ethiopia2008Ingår i: Southern Forests: a Journal of Forest Science, Vol. 70, nr 3, s. 193-203Artikel i tidskrift (Refereegranskat)
  • 19.
    Bjärstig, Therese
    et al.
    Umeå universitet, Samhällsvetenskapliga fakulteten, Statsvetenskapliga institutionen.
    Sténs, Anna
    Umeå universitet, Humanistiska fakulteten, Institutionen för idé- och samhällsstudier.
    Social values of forests and production of new goods and services: the views of Swedish family forest owners2018Ingår i: Small-scale Forestry, ISSN 1873-7617, E-ISSN 1873-7854, Vol. 17, nr 1, s. 125-146Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Forests are considered crucial assets for sustainable rural development, and contemporary forestry is an industry where production, environmental and social goals can – and should – be handled simultaneously. Swedish family forest owners (FFOs) are expected to both manage and conserve their forests for the benefit of the whole country, but there are contradictions between development and conservation and between traditional and alternative forms of utilization, representing dilemmas in rural areas. Tensions between urban and rural areas, between demands on what to produce and protect, are often linked to the FFOs’ views on opportunities for forest management. The aim of this study is to identify and analyse the extent to which FFOs perceive that social values have the ability to generate “new” goods and services as a supplement or alternative to traditional forestry, and to suggest how the forests might be managed to render high social values. Fifty-seven interviews were conducted with FFOs (both resident and non-resident). The results indicate that regardless of where they reside, FFOs have a multifunctional view of their forests and forest management, that the social values attached to forests can play an important role in the development of local recreation- and forest-based tourism activities, and in this respect they can enhance sustainable rural development. It is, however, not obvious who might start and develop these businesses, since there seems to be a lack of interest among the FFOs themselves.

  • 20. Blennow, Kristina
    et al.
    Persson, Erik
    Sveriges Lantbruksuniversitet.
    Societal impacts of storm damage2013Ingår i: Living with storm damage to forests / [ed] Barry Gardiner, Andreas Schuck, Mart-Jan Schelhaas, Christophe Orazio, Kristina Blennow, Bruce Nicoll, European Forest Institute , 2013, s. 70-77Kapitel i bok, del av antologi (Övrigt vetenskapligt)
    Abstract [en]

    Wind damage to forests can be divided into (1) the direct damage done to the forest and (2) indirect effects. Indirect effects may be of different kinds and may affect the environment as well as society. For example, falling trees can lead to power and telecommunication failures or blocking of roads. The salvage harvest of fallen trees is another example and one that involves extremely dangerous work. In this overview we provide examples of different entities, services, and activities that may be affected by wind damage to forests. We illustrate how valuation of the damage depends on the perspective applied and how the affected entities, services, and activities may represent different types of values. Finally we suggest means for how to actively manage the risk in an ethically sustainable way. Many of our examples will be drawn from the experiences of the wind damage Gudrun in southern Sweden on 8-9 January 2005. The direct as well as indirect effects, which are described, are by no means unique to the Gudrun wind damage event and similar or even worse effects have been described after the wind damage events Martin and Lothar in 1999, and Klaus in 2009

  • 21.
    Blennow, Kristina
    et al.
    Sveriges lantbruksuniversitet.
    Persson, Erik
    Sveriges Lantbruksuniversitet.
    Lindner, Marcus
    Pacheco Faias, Sònia
    Hanewinkel, Hanewinkel
    Forest owner motivations and attitudes towards supplying biomass for energy in Europe2014Ingår i: Biomass and Bioenergy, ISSN 0961-9534, E-ISSN 1873-2909, Vol. 67, s. 223-230Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The European Commission expects the use of biomass for energy in the EU to increasesignificantly between 2010 and 2020 to meet a legally binding target to cover at least 20%of EU’s total energy use from renewable sources in 2020. According to estimates made bythe member states of the EU, the direct supply of biomass from forests is expected toincrease by 45% on a volume basis between 2006 and 2020 in response to increasingdemand (Beurskens LWM, Hekkenberg M, Vethman P. Renewable energy projections aspublished in the national renewable energy action plans of the European Member states.ECN and EEA; 2011. http://https://www.ecn.nl/docs/library/report/2010/e10069.pdf[accessed 25.04.2014]; Dees M, Yousef A, Ermert J. Analysis of the quantitative tables ofthe national renewable energy action plans prepared by the 27 European Union MemberStates in 2010. BEE working paper D7.2. Biomass Energy Europe project. FELIS e Departmentof Remote Sensing and landscape information Systems, University of Freiburg,Germany; 2011). Our aims were to test the hypotheses that European private forestowners’ attitudes towards supplying woody biomass for energy (1) can be explained bytheir responses to changes in prices and markets and (2) are positive so that the forestbiomass share of the EU 2020 renewable energy target can be met. Based on survey datacollected in 2010 from 800 private forest owners in Sweden, Germany and Portugal ourresults show that the respondents’ attitudes towards supplying woody biomass for energycannot be explained as direct responses to changes in prices and markets. Our results,furthermore, imply that European private forest owners cannot be expected tosupply the requested amounts of woody biomass for energy to meet the forest biomassshare of the EU 2020 renewable energy target, at least if stemwood is to play theimportant role as studies by Verkerk PJ, Anttila P, Eggers J, Lindner M, Asikainen A. Therealisable potential supply of woody biomass fromforests in the European Union. For EcolManag 2011;261: 2007e2015, UNECE and FAO. The European forest sector outlook study II 2010e2030. United Nations, New York and Geneva; 2011 [abbreviated to EFSOS II] andElbersen B, Staritsky I, Hengeveld G, Schelhaas MJ, Naeff H, Bo¨ ttcher H. Atlas of EUbiomass potentials; 2012. Available from: http://www.biomassfutures.eu [accessed14.10.2013] suggest.

  • 22.
    Bognounou, Fidele
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Hulme, Philip E.
    Oksanen, Lauri
    Suominen, Otso
    Olofsson, Johan
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Role of climate and herbivory on native and alien conifer seedling recruitment at and above the Fennoscandian tree line2018Ingår i: Journal of Vegetation Science, ISSN 1100-9233, E-ISSN 1654-1103, Vol. 29, nr 4, s. 573-584Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Questions: We investigated the importance of climate and herbivory on native and alien conifer colonization of the birch-dominated Fennoscandian tree line by addressing the following questions: (a) are tree line and tundra habitats similarly suitable for conifer seedling recruitment; (b) do ungulate and rodent herbivores differentially impact seedling recruitment; and (c) how does the role of habitat and herbivory on seedling recruitment vary across a marked climate gradient?

    Location: Northern Fennoscandia, Sweden (Vassijaure and Paddus), and Norway (Joatka and Seiland).

    Methods: We conducted an experiment to assess the emergence rate, survival probability and height development of Norway spruce (Picea abies), Scots pine (Pinus sylvestris) and Siberian larch (Larix sibirica) seedlings. Three experimental plots (i.e., open control, reindeer exclosure and complete vertebrate exclosure) were established in both tree line and tundra habitats at each of the four locations. Seeds of the three conifer species were sown in each plot in June 1999 during three consecutive years. The surviving seedlings were counted in August to September 1999, 2000, 2001, 2002 and 2007. The height of all seedlings was measured in 2007.

    Results: Our study reveals that Norway spruce, Scots pine and Siberian larch can regenerate from seed at and above the current tree line in northern Fennoscandia. Their performance was generally higher above tree line in tundra than at tree line, but depended on species identity, climate aridity and mammal herbivory, particularly by rodents. These results suggest that the species composition and latitudinal limit of the tree line in the future might depend not only on direct effects of the future climate on the current tree line species, but also on the intensity of alien and native conifer introductions, as well as changes in herbivore populations.

    Conclusion: If sufficient seeds of Norway spruce, Scots pine and Siberian larch should reach the current tree line, their performances will increase with a warmer and wetter climate, and this effect will be markedly modulated by herbivores (particularly rodents). Further work is required to extend these results to determine the ability of these conifers to become tree line-forming species in the future.

  • 23.
    Bostedt, Göran
    et al.
    Umeå universitet, Samhällsvetenskapliga fakulteten, Handelshögskolan vid Umeå universitet, Nationalekonomi. European Forest Institute, North European Regional Office, SLU, Umeå, Sweden; Department of Forest Economics, SLU, Umeå, Sweden.
    Mustonen, Mika
    LUKE, Finland.
    Gong, Peichen
    SLU.
    Increasing Forest Biomass Supply in Northern Europe – Countrywide Estimates and Economic Perspectives2016Ingår i: Scandinavian Journal of Forest Research, ISSN 0282-7581, E-ISSN 1651-1891, Vol. 31, nr 3, s. 314-322Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Woody biomass is the largest source of renewable energy in Europe, and the expected increase in demand for wood for energy purposes was the stimulus for writing this paper. Opportunities to increase the supply of forest biomass in the short and long term are discussed, as well as environmental side effects of intensive forest management. Focusing on northern Europe, national estimates of potential annual fellings and the corresponding potential amounts, simulated by the European Forest Information Scenario model, are then presented, as well as reported fellings. For the region as a whole, there seems to be substantial unused biophysical potential, although recent data from some countries indicate underestimated annual felling rates. We argue that an economic perspective is lacking in the debate about wood production for energy purposes in Europe and harvest potentials, and we discuss the effects of biophysical capacity limits in forest yield from a partial equilibrium perspective. Using a larger proportion of the biophysical potential in northern Europe than at present will entail trade-offs with environmental and social values, which means that strategies are needed to protect and account for the benefits and costs of all forms of ecosystem services.

  • 24.
    Bostedt, Göran
    et al.
    Umeå universitet, Samhällsvetenskapliga fakulteten, Centrum för miljö- och naturresursekonomi (CERE). Umeå universitet, Samhällsvetenskapliga fakulteten, Handelshögskolan vid Umeå universitet, Statistik. Department of Forest Economics, Swedish University of Agricultural Sciences, SLU, Umeå, Sweden.
    Zabel, Astrid
    Ekvall, Hans
    Planning on a wider scale: Swedish forest owners' preferences for landscape policy attributes2019Ingår i: Forest Policy and Economics, ISSN 1389-9341, E-ISSN 1872-7050, Vol. 104, s. 170-181Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A tax-fund system has been proposed to advance Swedish forest conservation. We present a choice experiment with Swedish private forest owners on preferences for attributes of a tax-fund system. Focusing on three aspects: (i) freedom to choose set-asides, (ii) equity issues, and (iii) frequency of nature inventories, we find two groups of forest owners. The first is opposed to interventions that could curtail liberty and oppose frequent nature inventories, while a smaller group would derive positive utility from jointly deciding on the location of set-asides with society. Both groups have a preference for changing the current tax-base to soil productivity or timber volume. The tax-base chosen together with the modalities of re-distributing the funds will determine the program's efficiency. The paper concludes that a tax-fund system could indeed be a way forward but would need to be designed in a participatory manner to reconcile forest owners, forest industry representatives, and conservationists.

  • 25.
    Brackin, Richard
    et al.
    Queensland, QLD, 4072, Australia.
    Näsholm, Torgny
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC). Department of Forest Ecology and Management, Swedish University of Agricultural Sciences, SE-901 83 Umeå, Sweden.
    Robinson, Nicole
    School of Agriculture and Food Sciences, The University of Queensland, QLD, 4072, Australia.
    Guillou, Stephane
    School of Agriculture and Food Sciences, The University of Queensland, QLD, 4072, Australia.
    Vinall, Kerry
    School of Agriculture and Food Sciences, The University of Queensland, QLD, 4072, Australia.
    Lakshmanan, Prakash
    Sugar Research Australia, 50 Meiers Road, Indooroopilly, QLD 4068, Australia.
    Schmidt, Susanne
    School of Agriculture and Food Sciences, The University of Queensland, QLD, 4072, Australia.
    Inselsbacher, Erich
    Department of Forest Ecology and Management, Swedish University of Agricultural Sciences, SE-901 83 Umeå, Sweden; University of Vienna, Department of Geography and Regional Research, Vienna, AT-1090, Austria.
    Nitrogen fluxes at the root-soil interface show a mismatch of nitrogen fertilizer supply and sugarcane root uptake capacity2015Ingår i: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 5, artikel-id 15727Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Globally only approximate to 50% of applied nitrogen (N) fertilizer is captured by crops, and the remainder can cause pollution via runoff and gaseous emissions. Synchronizing soil N supply and crop demand will address this problem, however current soil analysis methods provide little insight into delivery and acquisition of N forms by roots. We used microdialysis, a novel technique for in situ quantification of soil nutrient fluxes, to measure N fluxes in sugarcane cropping soils receiving different fertilizer regimes, and compare these with N uptake capacities of sugarcane roots. We show that in fertilized sugarcane soils, fluxes of inorganic N exceed the uptake capacities of sugarcane roots by several orders of magnitude. Contrary, fluxes of organic N closely matched roots' uptake capacity. These results indicate root uptake capacity constrains plant acquisition of inorganic N. This mismatch between soil N supply and root N uptake capacity is a likely key driver for low N efficiency in the studied crop system. Our results also suggest that (i) the relative contribution of inorganic N for plant nutrition may be overestimated when relying on soil extracts as indicators for root-available N, and (ii) organic N may contribute more to crop N supply than is currently assumed.

  • 26.
    Bradshaw, R.H.W.
    et al.
    Dept. of Quaternary Geology, Geol. Surv. of Denmark and Greenland, Øster Voldgade 10, DK-1350 Copenhagen K, Denmark .
    Wolf, Annett
    Umeå universitet. Dept. of Quaternary Geology, Geol. Surv. of Denmark and Greenland, Øster Voldgade 10, DK-1350 Copenhagen K, Denmark : Dept. Phys. Geogr. Ecosyst. Anal., Geobiosphere Science Centre, Lund Univ., Sölvegatan 12, SE-223 62 Lund, Sweden .
    Møller, P.F.
    Long-term succession in a Danish temperate deciduous forest2005Ingår i: Ecography, Vol. 28, nr 2, s. 157-164Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Forest successional trajectories covering the last 2000 yr from a mixed deciduous forest in Denmark show a gradual shift in dominance from Tilia cordata to Fagus sylvatica and a recent increase in total forest basal area since direct management ceased in 1948. The successions are reconstructed by combining a fifty-year record of direct tree observations with local pollen diagrams from Draved Forest, Denmark. Five of the seven successions record a heathland phase of Viking Age dating from 830 AD. The anthropogenic influence is considerable throughout the period of study even though Draved contains some of the most pristine forest stands in Denmark. Anthropogenic influence including felling masks the underlying natural dynamics, with the least disturbed sites showing the smallest compositional change. Some effects of former management, such as loss of Tilia cordata dominance, are irreversible. Artificial disturbance, particularly drainage, has accelerated and amplified the shift towards Fagus dominance that would have occurred on a smaller scale and at a slower rate in the absence of human intervention. Copyright © Ecography 2005.

  • 27.
    Bruno, Karl
    Kungliga Tekniska Högskolan, Stockholm.
    Silvi-kulturella möten: Sveriges lantbruksuniversitet och högre skoglig utbildning i Etiopien 1986–20092017Ingår i: Nordic Journal of Educational History, ISSN 2001-7766, E-ISSN 2001-9076, Vol. 4, nr 1, s. 29-51Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Silvi-Cultural Encounters: The Swedish University of Agricultural Sciences and Higher Forestry Education in Ethiopia, 1986–2009

    The article discusses the Swedish University of Agricultural Sciences’ support to higher forestry education in Ethiopia, which took place between 1986 and 2009 in the context of Swedish-Ethiopian development cooperation. Against a growing historical interest in transnational encounters within the field of education, it analyses how Swedish forestry experts designed educational programs and taught in new environments. The concept of "silvi-culture" is introduced to signify that the tensions that arose within this aid effort related both to the technicalities of forestry education and to diverging academic and social cultures. The article is structured around three kinds of "silvi-cultural encounters" that describe the development of the project both chronologically and thematically. These encounters are used to demonstrate how the forest as a concrete, physical place was of central importance to the Swedish experts, as well as to show how they were guided by preconceptions developed within the framework of a Swedish silvi-culture that was only partially compatible with the conditions in Ethiopia.

  • 28. Cairns, David M.
    et al.
    Lafon, Charles W.
    Mouton, Michelle F.
    Stuteville, Rachel L.
    Young, Amanda B.
    Moen, Jon
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Comparing two methods for ageing trees with suppressed, diffuse-porous rings (Betula pubescens ssp. czerepanovii)2012Ingår i: Dendrochronologia, ISSN 1125-7865, E-ISSN 1612-0051, Vol. 30, nr 4, s. 252-256Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The annual growth rings of diffuse porous species such as mountain birch are often difficult to distinguish when samples are collected from trees that grow at treeline or in other harsh environments. In this study we document the differences in seedling and sapling ring counts obtained from two methods of analysis: a traditional analysis based on reflected light and low-power microscopy and one based on transmitted light with higher power magnification that uses thin-sections of the samples. Rings are easier to resolve using the more labor-intensive transmitted light method. Small rings are often missed when using the reflected light method, resulting in an underestimation of tree age. The dates estimated by the standard method agreed with those determined using the thin-sectioning method in 9.6% of the cases. Most commonly, the standard method gave a younger age than did thin-sectioning (72.4% of the trees). In only 18.03% of the cases did the standard method result in a greater age than did thin-sectioning. The reflected light method produced age estimations that were on average 1.37 years younger than those determined using the transmitted light method. The difference between the two methods was positively correlated with age and negatively correlated with mean ring-width. Age-class histograms based on the two methods show little difference at coarser aggregation levels (decades and pentads), but annualized age-class histograms have less agreement between the two methods. Therefore, we suggest using the more labor-intensive thin-sectioning method when annualized age counts are necessary in suppressed seedlings and saplings, for example, comparing tree establishment with annual climate conditions at treeline.

  • 29. Carlsson, Johanna
    et al.
    Egertsdotter, Ulrika
    Ganeteg, Ulrika
    Svennerstam, Henrik
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC).
    Nitrogen utilization during germination of somatic embryos of Norway spruce: revealing the importance of supplied glutamine for nitrogen metabolism2019Ingår i: Trees, ISSN 0931-1890, E-ISSN 1432-2285, Vol. 33, nr 2, s. 383-394Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Key messageThis paper shows that germinating Norway spruce somatic embryos are dependent on the carbon and nitrogen supplied in the medium, and that supplied glutamine accounts for 50 % of assimilated nitrogen during germination.AbstractThe female megagametophyte, which provides the zygotic embryo with nitrogen (N), carbon (C) and energy during germination, is not present in Norway spruce (Picea abies) mature somatic embryos. Therefore, somatic embryos presumably rely on nutrients supplied in the germination medium in addition to their storage compounds accumulated during maturation. However, to what extent stored versus supplied compounds contribute to a somatic embryo germination is unclear. In this 24-day study, we addressed the above question by monitoring the biomass changes and the N and C budget during somatic embryo germination, under low-intensity red light. We found that the C and N storage reserves, accumulated during the maturation phase, were not sufficient to support the growth of the germinating somatic embryos, rather they were dependent on the medium components. In addition, in a previous study it has been found that glutamine (Gln) supplied in the medium was crucial for maintaining the primary amino acid (AA) metabolism and growth of the proliferating embryogenic cultures of Norway spruce (Carlsson et al., PLoS One 12(8):e0181785, 2017). Therefore, we hypothesised that Gln would be required as a significant source of N also during somatic embryo germination. By tracing the uptake of isotopically labelled N-sources from the medium and further into primary N assimilation, we found that Gln was the preferred source of N for the germinating somatic embryos, accounting for 50% of assimilated N. As the amounts of both arginine (Arg) and Gln were increased in the germinating somatic embryos, it also suggested that germination in low-intensity red light promoted N storage, similar to what has been observed in the zygotic embryo maturation in conifers (King, Gifford, Plant Physiol 113:1125-1135, 1997).

  • 30. Carlsson, Julia
    et al.
    Lidestav, Gun
    Bjärstig, Therese
    Umeå universitet, Samhällsvetenskapliga fakulteten, Statsvetenskapliga institutionen.
    Svensson, Johan
    Nordström, Eva-Maria
    Att planera för hela skogslandskapet: utmaningar och möjligheter2016Rapport (Övrig (populärvetenskap, debatt, mm))
    Abstract [en]

    Skogens många värden behöver samplaneras och sättas i sitt sammanhang utifrån ett landskapsperspektiv. Vi intervjuade skogsägare och skogliga intressenter om hur de ser på skogens värden, äganderätten och skogspolitiska förutsättningar, samt synen på att samarbeta och ta hänsyn till varandras intressen. Vi utgår från behov identifierade i planeringsprocesser som inkluderar många deltagare och intressen, när det gäller att förbättrakommunikation, information och mötesplatser. Vi ser tre möjliga verktyg för att skapa förutsättningar för ett landskapsperspektiv i planeringen av skogens värden: en landskapslots, en samverkansarena, samt utformningen och användandet av skogsbruksplanen.

  • 31.
    Carvalho, Ricardo
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för tillämpad fysik och elektronik.
    Lindgren, Robert
    García-Lopez, Natxo
    Nyberg, Gert
    Boman, Christoffer
    Household Bioenergy Transitions with Alternative Biomass Feedstocks and Technologies: An Integrated System to Mitigate Environmental Risks in Western Kenya2018Ingår i: Household Bioenergy Transitions with Alternative Biomass Feedstocks and Technologies: An Integrated System to Mitigate Environmental Risks in Western Kenya / [ed] École Polytechnique Fédérale de Lausanne, UNESCO, Lausanne, 2018Konferensbidrag (Refereegranskat)
    Abstract [en]

    In Kenya, over 50% of the total primary energy consumption is from traditional solid-fuel cooking, being this a major cause of deforestation and household air pollution (HAP). Western Kenya has an agricultural biofuel feedstock of over 1.9 million Mt, which could be processed to supply cookstoves with crop-residue pellets and improved wood fallows. The sociotechnical viability of two novel bioenergy value chains were analysed using the Long-Range Energy Alternatives Planning system. Three scenarios of transition to efficient cookstoves and decentralized biofuel and electricity production systems were tested. In the “Optimal scenario”, the current feedstock in the Kisumu and Siaya counties could satisfy over 80% of the cooking energy demand by 2030. Here, the net greenhouse gas emissions from charcoal production and HAP could be reduced by 87% to 12.6 thousand Mt CO2e. Further work should integrate socioeconomic indicators reflecting additional local/regional stakeholders´ collaboration channels (cost-effective) to support the bioenergy transitions. 

  • 32. Chen, Dongmei
    et al.
    Zhang, Xianxian
    Kang, Hongzhang
    Sun, Xiao
    Yin, Shan
    Du, Hongmei
    Yamanaka, Norikazu
    Gapare, Washington
    Wu, Harry X.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC). Commonwealth Sci & Ind Res Org Plant Ind, Canberra, ACT, Australia.
    Liu, Chunjiang
    Phylogeography of Quercus variabilis Based on Chloroplast DNA Sequence in East Asia: Multiple Glacial Refugia and Mainland-Migrated Island Populations2012Ingår i: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 7, nr 10, s. e47268-Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The biogeographical relationships between far-separated populations, in particular, those in the mainland and islands, remain unclear for widespread species in eastern Asia where the current distribution of plants was greatly influenced by the Quaternary climate. Deciduous Oriental oak (Quercus variabilis) is one of the most widely distributed species in eastern Asia. In this study, leaf material of 528 Q. variabilis trees from 50 populations across the whole distribution (Mainland China, Korea Peninsular as well as Japan, Zhoushan and Taiwan Islands) was collected, and three cpDNA intergenic spacer fragments were sequenced using universal primers. A total of 26 haplotypes were detected, and it showed a weak phylogeographical structure in eastern Asia populations at species level, however, in the central-eastern region of Mainland China, the populations had more haplotypes than those in other regions, with a significant phylogeographical structure (N-ST = 0.751 > G(ST) = 0.690, P < 0.05). Q. variabilis displayed high interpopulation and low intrapopulation genetic diversity across the distribution range. Both unimodal mismatch distribution and significant negative Fu's F-S indicated a demographic expansion of Q. variabilis populations in East Asia. A fossil calibrated phylogenetic tree showed a rapid speciation during Pleistocene, with a population augment occurred in Middle Pleistocene. Both diversity patterns and ecological niche modelling indicated there could be multiple glacial refugia and possible bottleneck or founder effects occurred in the southern Japan. We dated major spatial expansion of Q. variabilis population in eastern Asia to the last glacial cycle(s), a period with sea-level fluctuations and land bridges in East China Sea as possible dispersal corridors. This study showed that geographical heterogeneity combined with climate and sea-level changes have shaped the genetic structure of this wide-ranging tree species in East Asia.

  • 33. Chen, Xinyu
    et al.
    Yuan, Huwei
    Hu, Xiange
    Meng, Jingxiang
    Zhou, Xianqing
    Wang, Xiao-Ru
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. National Engineering Laboratory for Forest Tree Breeding, Key Laboratory of Genetic and Breeding in Forest Trees and Ornamental Plants of Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, People’s Republic of China.
    Li, Yue
    Variations in electrical impedance and phase angle among seedlings of Pinus densata and parental species in Pinus tabuliformis habitat environment2015Ingår i: Journal of Forestry Research, ISSN 1007-662X, E-ISSN 1993-0607, Vol. 26, nr 3, s. 777-783Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Electrical impedance (EI) and phase angle (PHI) parameters in AC impedance spectroscopy are important electrical parameters in the study of medical pathology. However, little is known about their application in variation and genetic relationship studies of forest trees. In order to test whether impedance parameters could be used in genetic relationship analysis among conifer species, EI and PHI were measured in a seedling experiment test composed of Pinus tabuliformis, Pinus yunnanensis, and Pinus densata in a habitat of Pinus tabuliformis. The results showed that variations in both EI and PHI among species were significant in different electric frequencies, and the EI and PHI values measured in the two populations of P. densata were between the two parental species, P. yunnanensis and P. tabuliformis. These results show that these two impedance parameters could reflect the genetic relationship among pine species. This was the first time using the two AC impedance spectroscopy parameters to test the genetic relationship analysis between tree species, and would be a hopeful novel reference methodology for future studies in evolution and genetic variation of tree species.

  • 34.
    Cronie, Ottmar
    et al.
    Mathematical Sciences, Chalmers University of Technology and University of Gothenburg.
    Nyström, Kenneth
    SLU, Department of Forest Resource Management.
    Yu, Jun
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för matematik och matematisk statistik.
    Spatiotemporal Modeling of Swedish Scots Pine Stands2013Ingår i: Forest Science, ISSN 0015-749X, E-ISSN 1938-3738, Vol. 59, nr 5, s. 505-516Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The growth-interaction (GI) process is employed for the spatiotemporal modelling of measurements of locations and radii at breast height made at three different time points of the individual trees in ten Scots pine (Pinus sylvestris) plots from the Swedish NFI. The GI-process places trees at random locations in the study region and assigns sizes to the trees, which interact and grow with time. It has been used to model plots in previous studies and to improve the fit we suggest some modifications: a different location assignment strategy and a different open-growth (growth under negligible competition) function. We believe that the calibration data contain trees that are too small to reflect the open-growth properly, which primarily affects the carrying capacity parameter. To better represent the open-growth of Scots pines, we evaluate the open-growth from a separate set of data (size and age measurements of older and larger single Scots pines). A linear relationship is found between the plot's estimated site indices and the sizes, and this is exploited in the estimation of the carrying capacity. We finally estimate the remaining GI-process parameters and test the goodness-of-fit on simulated predictions from the fitted model.

  • 35.
    Cronie, Ottmar
    et al.
    Stochastics, CWI, Amsterdam, The Netherlands.
    Yu, Jun
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för matematik och matematisk statistik.
    The discretely observed immigration-death process: Likelihood inference and spatiotemporal applications2016Ingår i: Communications in Statistics - Theory and Methods, ISSN 0361-0926, E-ISSN 1532-415X, Vol. 45, nr 18, s. 5279-5298Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We consider a stochastic process, the homogeneous spatial immigration-death (HSID) process, which is a spatial birth-death process with as building blocks (i) an immigration-death (ID) process (a continuous-time Markov chain) and (ii) a probability distribution assigning iid spatial locations to all events. For the ID process, we derive the likelihood function, reduce the likelihood estimation problem to one dimension, and prove consistency and asymptotic normality for the maximum likelihood estimators (MLEs) under a discrete sampling scheme. We additionally prove consistency for the MLEs of HSID processes. In connection to the growth-interaction process, which has a HSID process as basis, we also fit HSID processes to Scots pine data.

  • 36.
    Cronie, Ottmar
    et al.
    Chalmers University of Technology, Göteborg.
    Yu, Jun
    Centre of Biostochatics, SLU.
    Nyström, Kenneth
    Forest Resource Management, SLU.
    Spatio-Temporal Modelling of Swedish Scots Pine Stands2011Rapport (Övrigt vetenskapligt)
    Abstract [en]

    Considering measurements of locations and radii at breast height made at three different time points of the individual trees in ten Swedish Scots pine plots, we employ the so called growth-interaction (GI) process for the spatio-temporal modelling of the plots. The GI-process places trees at random locations in the study region and assigns radii (sizes) to the trees, which interact and grow with time. It has been used to model Scots pine plots in previous studies, and to improve the fit we suggest some modifications of the model: A different location assignment strategy and a different function for the open-growth (growth in absence of competition). We believe also that the space-time data contain too small trees to reflect the open-growth properly, which primarily affectsthe carrying capacity parameter. We evaluate the open-growth froma separate set of data which consists of size and age measurements ofolder and larger single Scots pines. This data set better represents the open-growth of Scots pines than the space-time data sets. A linear relationship is found between the estimated site indexes of the plots and the sizes, and this relationship is exploited in the estimation of the carrying capacity. For each of the ten space-time data sets (plots) we estimate the remaining parameters of the GI-process and finally, by means of some Monte Carlo tests, we test the goodness-of-fit of simulated predictions from the fitted model.

  • 37. Dahlström, N
    et al.
    Jönsson, K
    Nilsson, Christer
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Long term dynamics of large woody debris in a managed boreal forest stream2005Ingår i: Forest Ecology and Management, ISSN 0378-1127, E-ISSN 1872-7042, Vol. 210, nr 1-3, s. 363-373Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Little is known about how past forest management in Sweden influenced the quantity and quality of large woody debris (LWD) in streams. The present study provides information of the long-term dynamics of LWD in a reach of a boreal stream intersecting a managed forest. Dendrochronological methods were used to reconstruct mortality years of the pieces of LWD and the general history of fire and cuttings of the surrounding riparian forest. Today, spruce dominates among the living trees, whereas the LWD is dominated by birch in the forest and by pine in the stream. Fire frequency prior to active fire suppression was similar to values reported from boreal forests. Pine trees were more abundant in the riparian forest before selective logging operations and active fire suppression began in the 1800s. Many of the pieces of LWD found in the stream today died more than 200 years ago and derived from a cohort of pines that generated in the early 1600s. Pine LWD in stream channels is highly resistant to decomposition and can reside for more than 300 years. A substantial amount of the LWD found today in managed forest streams in boreal Sweden most likely derives from the time before extensive human influence and is likely to decrease further in the future. Management of riparian forests to ascertain future supply of long-lived LWD in streams should target to increase the proportion of pine trees.

  • 38.
    de La Torre, Amanda R
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Birol, Inanc
    Bousquet, Jean
    Ingvarsson, Pär K
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC). Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik.
    Jansson, Stefan
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC). Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik.
    Jones, Steven J. M
    Keeling, Christopher I
    MacKay, John
    Nilsson, Ove
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC). Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik.
    Ritland, Kermit
    Street, Nathaniel
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC). Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik.
    Yanchuk, Alvin
    Zerbe, Philipp
    Bohlmann, Jörg
    Insights into conifer giga-genomes2014Ingår i: Plant Physiology, ISSN 0032-0889, E-ISSN 1532-2548, Vol. 166, nr 4, s. 1724-1732Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Insights from sequenced genomes of major land plant lineages have advanced research in almost every aspect of plant biology. Until recently, however, assembled genome sequences of gymnosperms have been missing from this picture. Conifers of the pine family (Pinaceae) are a group of gymnosperms that dominate large parts of the world's forests. Despite their ecological and economic importance, conifers seemed long out of reach for complete genome sequencing, due in part to their enormous genome size (20-30 Gb) and the highly repetitive nature of their genomes. Technological advances in genome sequencing and assembly enabled the recent publication of three conifer genomes: white spruce (Picea glauca), Norway spruce (Picea abies), and loblolly pine (Pinus taeda). These genome sequences revealed distinctive features compared with other plant genomes and may represent a window into the past of seed plant genomes. This Update highlights recent advances, remaining challenges, and opportunities in light of the publication of the first conifer and gymnosperm genomes.

  • 39. Didion, M.
    et al.
    Kupferschmid, A.D.
    Wolf, A.
    Forest Ecology, Institute of Terrestrial Ecosystems, Department of Environmental Sciences, Swiss Federal Institute of Technology ETH, Universitätstr. 22, CH 8092 Zurich, Switzerland.
    Bugmann, H.
    Ungulate herbivory modifies the effects of climate change on mountain forests2011Ingår i: Climatic Change, ISSN 0165-0009, E-ISSN 1573-1480, Vol. 109, nr 3-4, s. 647-669Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Recent temperature observations suggest a general warming trend that may be causing the range of tree species to shift to higher latitudes and altitudes. Since biotic interactions such as herbivory can change tree species composition, it is important to understand their contribution to vegetation changes triggered by climate change. To investigate the response of forests to climate change and herbivory by wild ungulates, we used the forest gap model ForClim v2. 9. 6 and simulated forest development in three climatically different valleys in the Swiss Alps. We used altitudinal transects on contrasting slopes covering a wide range of forest types from the cold (upper) to the dry (lower) treeline. This allowed us to investigate (1) altitudinal range shifts in response to climate change, (2) the consequences for tree species composition, and (3) the combined effect of climate change and ungulate herbivory. We found that ungulate herbivory changed species composition and that both basal area and stem numbers decreased with increasing herbivory intensity. Tree species responded differently to the change in climate, and their ranges did not change concurrently, thus causing a succession to new stand types. While climate change partially compensated for the reductions in basal area caused by ungulate herbivory, the combined effect of these two agents on the mix of the dominant species and forest type was non-compensatory, as browsing selectively excluded species from establishing or reaching dominance and altered competition patterns, particularly for light. We conclude that there is an urgent need for adaptive forest management strategies that address the joint effects of climate change and ungulate herbivory. 

  • 40. Ding, Jihua
    et al.
    Böhlenius, Henrik
    Rühl, Mark Georg
    Chen, Peng
    Sane, Shashank
    Zambrano, Jose A.
    Zheng, Bo
    Nilsson, Ove
    Eriksson, Maria E.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC).
    GIGANTEA-like genes control seasonal growth cessation in Populus2018Ingår i: New Phytologist, ISSN 0028-646X, E-ISSN 1469-8137, Vol. 218, nr 4, s. 1491-1503Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Survival of trees growing in temperate zones requires cycling between active growth and dormancy. This involves growth cessation in the autumn triggered by a photoperiod shorter than the critical day length. Variations in GIGANTEA (GI)-like genes have been associated with phenology in a range of different tree species, but characterization of the functions of these genes in the process is still lacking. We describe the identification of the Populus orthologs of GI and their critical role in short-day-induced growth cessation. Using ectopic expression and silencing, gene expression analysis, protein interaction and chromatin immunoprecipitation experiments, we show that PttGIs are likely to act in a complex with PttFKF1s (FLAVIN-BINDING, KELCH REPEAT, F-BOX 1) and PttCDFs (CYCLING DOF FACTOR) to control the expression of PttFT2, the key gene regulating short-day-induced growth cessation in Populus. In contrast to Arabidopsis, in which the GI-CONSTANS (CO)-FLOWERING LOCUS T (FT) regulon is a crucial day-length sensor for flowering time, our study suggests that, in Populus, PttCO-independent regulation of PttFT2 by PttGI is more important in the photoperiodic control of growth cessation and bud set.

  • 41.
    Eckerberg, Katarina
    et al.
    Umeå universitet, Samhällsvetenskapliga fakulteten, Statsvetenskapliga institutionen.
    Buizer, Marleen
    Fires, forests and conflict in times of rapid environmental change in Sweden and Australia2014Ingår i: International forestry review, ISSN 1465-5489, E-ISSN 2053-7778, Vol. 16, nr 5, s. 53-Artikel i tidskrift (Övrigt vetenskapligt)
    Abstract [en]

    Environmental problems seem to be increasingly complex, hard to solve by instrumental rationality, and laden with conflict when they demand human interventions in nature. The use of fire is one such contested intervention. This paper examines the role of conflict and deliberation in forest fire management practices in Sweden and Australia whose landscapes have historically been shaped by fire. In Sweden, burning is gradually emerging on foresters' and nature conservationists' agendas for nature conservation purposes. In Australia, prescribed burning has been practiced on a relatively broad scale, chiefly to prevent larger fires and also for nature conservation purposes. Touching on a wide range of values, including biological diversity, human safety, traditional heritage and professional identity, fire management is often the topic of fierce debate. Contemporary politics places high expectations on collaborative governance, drawing attention to the twin concepts of conflict management and deliberation. How does collaborative governance manifest itself relating to fire management? And what are its chances considering the Swedish and Australian contexts with their strong reliance on technical scientific expertise? We conclude that forms of local, collaborative governance in which confl icts and difference have a place, rather than generalized knowledge, are promising but rare processes to move forward.

  • 42.
    Eckerberg, Katarina
    et al.
    Umeå universitet, Samhällsvetenskapliga fakulteten, Statsvetenskapliga institutionen.
    Buizer, Marleen
    Land Use Planning Group, Wageningen University, The Netherlands.
    Promises and dilemmas in forest fire management decision-making: exploring conditions for community engagement in Australia and Sweden2017Ingår i: Forest Policy and Economics, ISSN 1389-9341, E-ISSN 1872-7050, Vol. 80, s. 133-140Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Prescribed burning, to prevent larger fires or to encourage ecological restoration, is a highly contested practice, raising both complex practical questions relating to safety and techniques, and deep philosophical questions about the relationship between people and nature. Previous research either analyses conflict in forest fire management, or argues for social learning but does not discuss how this might happen. We explore what community engagement in fire management might contribute, and how policy conditions enable or constrain deliberative practices in fire management in two very different countries, Sweden and Australia. In Sweden, burning is gradually emerging on foresters' and nature conservationists' agendas, whereas in Australia, prescribed burning has been practiced and debated on a relatively broad scale for some time. Both countries rely much on technical expertise, while merging this with local knowledge in transformative processes in which conflicts and difference have a place could enhance the quality of the debates.

  • 43.
    Egertsdotter, Ulrika
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC). Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, Umeå, Sweden.
    Plant physiological and genetical aspects of the somatic embryogenesis process in conifers2019Ingår i: Scandinavian Journal of Forest Research, ISSN 0282-7581, E-ISSN 1651-1891, Vol. 34, nr 5, s. 360-369Artikel, forskningsöversikt (Refereegranskat)
    Abstract [en]

    The processes for producing conifer planting stock by somatic embryogenesis (SE) in conifers are described. Implementation of SE presents opportunities and limitations at various stages of the in vitro process. The topic of genetic stability, or somaclonal variation, is a particular concern and reviewed. Following the in vitro processes, several factors affect the successful acclimation, early growth and field performance of SE planting stock. Experiences with other conifer species in the context of commercial production are reviewed. While SE production has historically been a very labor-intensive process, recent advances have been made to automate the various steps. Developments to enable SE for Norway spruce in Sweden are described.

  • 44. Eklöf, Karin
    et al.
    Bishop, Kevin
    Bertilsson, Stefan
    Björn, Erik
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Buck, Moritz
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen. 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 operations2018Ingår i: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 613-614, s. 1069-1078Artikel i tidskrift (Refereegranskat)
    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. 

  • 45.
    Ekvall, Hans
    et al.
    Sveriges Lantbruksuniversitet.
    Bostedt, Göran
    Umeå universitet, Samhällsvetenskapliga fakulteten, Handelshögskolan vid Umeå universitet, Nationalekonomi. Umeå universitet, Samhällsvetenskapliga fakulteten, Centrum för miljö- och naturresursekonomi (CERE). Sveriges Lantbruksuniversitet.
    Jonsson, Mattias
    Sveriges Lantbruksuniversitet.
    Least-Cost Allocation of Measures to Increase the Amount of Coarse Woody Debris in Forest Estates2013Ingår i: Journal of Forest Economics, ISSN 1104-6899, E-ISSN 1618-1530, Vol. 19, nr 3, s. 267-285Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Coarse woody debris (CWD) is crucial for maintaining biodiversity in forests but conservation measures to increase CWD must be performed cost efficiently. We estimate least-cost combinations of CWD-increasing measures in a spruce-dominated Swedish forest estate. Specifically, we investigate how using combinations of the measures tree retention, creating high stumps, manual scarification, prolonged rotations, and retention of dying trees impacts the amount of CWD and net present value at the estate level. We found that by combining CWD-increasing measures in an optimal way the amount of CWD on the estate could be increased 322% with a decrease in present value of only 10%. The optimal combination of conservation measures depends on the desired increase in CWD. The analysis thus shows that huge improvements in cost-efficiency of biodiversity-oriented forestry are possible.

  • 46.
    Ekvall, Hans
    et al.
    Sveriges Lantbruksuniversitet.
    Löfgren, Stefan
    Sveriges Lantbruksuniversitet.
    Bostedt, Göran
    Umeå universitet, Samhällsvetenskapliga fakulteten, Handelshögskolan vid Umeå universitet, Nationalekonomi.
    Ash recycling: a method to improve forest production or to restore acidified surface waters?2014Ingår i: Forest Policy and Economics, ISSN 1389-9341, E-ISSN 1872-7050, Vol. 45, s. 42-50Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This cost-benefit analysis compared different strategies for ash recycling in southern Swedish forests, with a special emphasis on the potential to use ash recycling as a measure to ameliorate acidification of soils and surface waters caused by acid deposition. Benefit transfer was used to estimate use values for sport fishing and non-use values in terms of existence values. The results show that the optimal share of acidified forest land that should be treated with ash depends on how optimistic one is about the effect of using ash to restore lakes and streams from acidification. More optimistic assumptions imply that the ash to larger extent should be used to ameliorate acidification. Using the most realistic assumption, given the experiences of forest liming, shows that acidified forest land should not be treated with ash with the aim of restoring lakes and streams from acidification. From a socioeconomic point of view, ash simply does more good as fertilizer on forested organic soils.

    (C) 2014 Elsevier B.V. All rights reserved.

  • 47. Eriksson, Anna-Maria
    et al.
    Olsson, Jörgen
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Jonsson, Bengt Gunnar
    Toivanen, Sara
    Edman, Mattias
    Effects of restoration fire on dead wood heterogeneity and availability in three Pinus sylvestris forests in Sweden2013Ingår i: Silva Fennica, ISSN 0037-5330, E-ISSN 2242-4075, Vol. 47, nr 2, s. 954-Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Restoration fires are increasingly used as a conservation tool in Sweden to recreate forests with characteristics of previous forests that were periodically disturbed by fires and promote fire-dependent species. Restoration fires can result in large inputs of fresh dead wood, but there are risks of losing some of the existing, pre-fire dead wood. To assess these counteracting effects we studied the heterogeneity and availability of dead wood before and after three restoration fires in boreal Scots pine forests. Specifically, we studied volumes of stumps, high stumps, snags and logs. The fires decreased the total volume of pre-fire dead wood (23-41%) and consumed logs in late decay stages (26-54%) to a higher extent than logs in earlier stages. The input of new fresh dead wood after the fires exceeded losses of pre-fire dead wood and resulted in a net increase of dead wood in all three sites. The added dead wood consisted of fresh snags killed by the fires. Fire also affected log characteristics: reducing their vegetation coverage (60-98%), decreasing their ground contact (4-50%) and increasing their surface area of charred wood (>50%). Such changes have important consequences for the micro environmental conditions inside logs, but have been rarely studied in relation to restoration fires. Our results show that restoration fire causes changes in dead wood availability and characteristics of logs. The results imply that ideally stands with low abundance of rare and heavily decayed wood substrates should be burned to optimize dead wood values. Alternatively, management practices should include protection of these substrates during restoration fires.

  • 48.
    Eriksson, Louise
    Umeå universitet, Samhällsvetenskapliga fakulteten, Institutionen för geografi och ekonomisk historia.
    Risk Perception and Responses Among Private Forest Owners in Sweden2014Ingår i: Small-scale Forestry, ISSN 1873-7617, E-ISSN 1873-7854, Vol. 13, nr 4, s. 483-500Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Forest risk management influences economic, recreation, and ecological values in the forest. To improve the understanding of forest risk management among private forest owners, in-depth interviews were carried out with 20 individual private forest owners in Sweden. Within an environmental stress framework, the forest owners' overall perception of a range of risks, or threats, that they perceive may damage their forest or harm them as a forest owner was uncovered. Overall, results revealed that the owners generally were not very concerned about forest risks. Nevertheless, natural hazards, such as storms and fires, and societal processes including political decisions concerning for example environmental regulations were mentioned among the most serious threats. Proactive as well as reactive strategies were used to deal with the risks-for example, insurance and forest management strategies. Because climate change is a potentially new risk that may affect forest owners, the owners' climate change perceptions were explored. The owners emphasised uncertainties and displayed a rather optimistic view of the impacts of climate change on their forests now and in the future. Two dimensions-risk tolerance and perceived control over risks-characterised forest owners' risk perception and responses. In addition, the susceptibility of the forest, previous risk experience, forest values, and the extent to which the owner is dependent on the forest-for example, economically-were relevant for understanding how risks are evaluated.

  • 49.
    Eriksson, Louise
    et al.
    Umeå universitet, Samhällsvetenskapliga fakulteten, Institutionen för geografi.
    Klapwijk, Maartje J.
    Attitudes towards biodiversity conservation and carbon substitution in forestry: a study of stakeholders in Sweden2019Ingår i: Forestry (London), ISSN 0015-752X, E-ISSN 1464-3626, Vol. 92, nr 2, s. 219-229Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Global change has fueled debates on forest use and management, including the need to adapt management to mitigate future risks in forestry. Additionally, forests are important for biodiversity conservation and could be used in climate change mitigation. The opinions of stakeholders towards acceptable forest use deserve consideration. This study examined relations between environmental problem awareness, forest beliefs and environmental management attitudes (biodiversity conservation and carbon substitution) among stakeholders in Sweden, and explored the effect of a local biodiversity versus global climate change frame on attitudes. Stakeholders were recruited from ownership and environmental/recreational interest groups (owner and nature group, respectively) (membership sample) and among students (student sample). Whereas the owner group was more positive towards carbon substitution in forestry, the nature group was more positive towards biodiversity conservation and carbon storage. In the membership sample, awareness of biodiversity loss and eco-social forest beliefs influenced attitudes towards biodiversity conservation. In contrast, positive attitudes towards carbon substitution stemmed from lower awareness of biodiversity loss, less emphasis on openness towards new methods in forestry and greater emphasis on production in forestry. While framing did not influence attitudes, the cognitive hierarchy was useful in providing a nuanced understanding of stakeholders, valuable for policy and practice.

  • 50.
    Eriksson, Mathilda
    Umeå universitet, Samhällsvetenskapliga fakulteten, Handelshögskolan vid Umeå universitet, Nationalekonomi.
    The role of the forest in an integrated assessment model of the climate and the economy2015Ingår i: Climate Change Economics, ISSN 2010-0078, E-ISSN 2010-0086, Vol. 6, nr 3, artikel-id 1550011Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This paper develops the FOR-DICE model to explore the potential role of the global forest in reducing climate change. It presents a basic framework for assessing the boreal, tropical, and temperate forests as both a source of renewable energy and a resource to sequester and store carbon. The focus of the paper is to explore whether climate policies should focus on increasing the forest biomass, to sequester and store carbon, or on increasing the use of the forest biomass as a source of energy, to substitute fossil fuels. The paper shows that the global forest can play an important role in reducing atmospheric carbon. The main finding at the global level is that it is better to increase the forest biomass rather than increase the use of forest bioenergy. The reason for this is that the decrease in forest carbon stock created by increased bioenergy harvests is not offset by avoided fossil fuel emissions. This finding suggests that setting high bioenergy targets, without considering the dynamics of the forest stock and the efficiency of bioenergy, will be detrimental to climate change mitigation.

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