lnu.sePublikasjoner
Endre søk
Link to record
Permanent link

Direct link
BETA
Publikasjoner (10 av 36) Visa alla publikasjoner
Nilsson, D., Nilsson, B., Thörnqvist, T. & Bergh, J. (2018). Amount of nutrients extracted and left behind at a clear-felled area using the fresh-stacked and dried-stacked methods of logging residue extraction. Scandinavian Journal of Forest Research, 33(5), 437-445
Åpne denne publikasjonen i ny fane eller vindu >>Amount of nutrients extracted and left behind at a clear-felled area using the fresh-stacked and dried-stacked methods of logging residue extraction
2018 (engelsk)Inngår i: Scandinavian Journal of Forest Research, ISSN 0282-7581, E-ISSN 1651-1891, Vol. 33, nr 5, s. 437-445Artikkel i tidsskrift (Fagfellevurdert) Published
Abstract [en]

Nutrient removal has been one of the key issues since the harvesting of logging residues started in Sweden. This study examined the actual removal of nutrients by measuring the amounts of biomass removed (from a forest products perspective) combined with their respective nutrient concentrations (N, P, Ca, K and Mg), from a clear-felled area when using the dried-stacked and fresh-stacked methods. The most important finding is that the two methods were very similar regarding nutrients remaining at the clear-felled area. Of the nutrients remaining there, most were found to be well distributed between the harvester heaps. Both methods fulfilled the requirements of the Swedish Forest Agency. A sensitivity analysis showed that even if the dried-stacked method left more needles, or the fresh-stacked method extracted more logging residues, there would only be a small impact on the levels of nutrients removed. The sensitivity analysis also showed that the amount of logging residues remaining between the harvester heaps seems to be much more important for nutrients left behind, regardless of extraction method. With this in mind, it is highly probable that improvements to the extraction of logging residues, without increasing nutrient removal, can be made.

sted, utgiver, år, opplag, sider
Taylor & Francis Group, 2018
Emneord
Forest fuel; storage; quality; needles; nitrogen; Norway spruce
HSV kategori
Forskningsprogram
Teknik, Skog och träteknik
Identifikatorer
urn:nbn:se:lnu:diva-72344 (URN)10.1080/02827581.2018.1427786 (DOI)000433155900004 ()2-s2.0-85041861691 (Scopus ID)
Tilgjengelig fra: 2018-04-09 Laget: 2018-04-09 Sist oppdatert: 2019-08-29bibliografisk kontrollert
Blom, Å., Johansson, J., Schauerte, T. & Thörnqvist, T. (2017). Utomhuskonstruktioner i trä: några erfarenheter från byggnation i trä av flerbostadshus. Linnéuniversitetet
Åpne denne publikasjonen i ny fane eller vindu >>Utomhuskonstruktioner i trä: några erfarenheter från byggnation i trä av flerbostadshus
2017 (svensk)Annet (Annet vitenskapelig)
Abstract [sv]

Användandet av materialet trä i produkter är ett lån från naturen som förr eller senare genom nedbrytning av vedsubstansen ska återföras till det naturliga kretsloppet. Avseende användningen av solitt trä i produkter bestäms tidsperioden innan återföringen till naturen av produktens konstruktion och trämaterialet i sig självt i relation till den omgivande miljön samt användningen och hanteringen av produkten. En produkts förmåga att motstå, eller behålla sina egenskaper trots dessa yttre påfrestningar benämns dess beständighet.

sted, utgiver, år, sider
Linnéuniversitetet, 2017. s. 33
HSV kategori
Forskningsprogram
Teknik, Skog och träteknik
Identifikatorer
urn:nbn:se:lnu:diva-72253 (URN)978-91-88357-93-9 (ISBN)
Tilgjengelig fra: 2018-04-05 Laget: 2018-04-05 Sist oppdatert: 2020-05-20bibliografisk kontrollert
Nilsson, D., Pettersson, R., Thörnqvist, T. & Nylinder, M. (2016). The importance of accurate measurement of comminuted logging residues’ moisture contents for small-scale forest owners. Drewno, 59(198), 99-110
Åpne denne publikasjonen i ny fane eller vindu >>The importance of accurate measurement of comminuted logging residues’ moisture contents for small-scale forest owners
2016 (engelsk)Inngår i: Drewno, ISSN 1644-3985, Vol. 59, nr 198, s. 99-110Artikkel i tidsskrift (Fagfellevurdert) Published
Abstract [en]

Bioenergy from logging residues is an important contributor to Swedish energysupplies. Thus, accurate measurements of delivered logging residues’ energycontents are very important for both sellers and buyers. Deliveries’ energycontents are highly correlated with their moisture contents, and thus aredetermined in southern Sweden (and elsewhere) by measuring their masses andmoisture contents. There is insufficient knowledge, however, about the variation inmoisture content within and between deliveries, and hence the minimum numberof samples needed to obtain the required precision. Thus, these variations wereexamined in detail in the presented study. Nested analysis of the variance of theacquired data shows that at least nine samples are required to obtain estimates ofa delivery’s moisture content with a 3% margin of error. For high volume trade,such as that between forest companies and the energy-conversion industry,current measurement practices are sufficiently accurate. For private forest ownersmaking single deliveries, however, higher precision is required as inaccuratemeasurements can strongly affect prices.

Emneord
forest residues, bioenergy, forest-fuel, scaling, moisture content, private forest owners
HSV kategori
Forskningsprogram
Teknik, Skog och träteknik; Teknik
Identifikatorer
urn:nbn:se:lnu:diva-55603 (URN)10.12841/wood.1644-3985.149.01 (DOI)000392473900008 ()2-s2.0-85010619024 (Scopus ID)
Tilgjengelig fra: 2016-08-18 Laget: 2016-08-17 Sist oppdatert: 2017-11-28bibliografisk kontrollert
Nilsson, B., Nilsson, D. & Thörnqvist, T. (2015). Distribution of logging residues at the clear-felled site after fuel adapted logging operations. In: Obernberger I, Baxter D, Grassi A, Helm P (Ed.), Papers of the 23rd European Biomass Conference: Setting the course for a biobased economyExtracted from the Proceedings of the International Conference held in Viennna, Asutria1-4 June 2015. Paper presented at 23rd European Biomass Conference 1-4 June 2015, Vienna Asutria (pp. 270-272). ETA-Florence Renewable Energies
Åpne denne publikasjonen i ny fane eller vindu >>Distribution of logging residues at the clear-felled site after fuel adapted logging operations
2015 (engelsk)Inngår i: Papers of the 23rd European Biomass Conference: Setting the course for a biobased economyExtracted from the Proceedings of the International Conference held in Viennna, Asutria1-4 June 2015 / [ed] Obernberger I, Baxter D, Grassi A, Helm P, ETA-Florence Renewable Energies , 2015, s. 270-272Konferansepaper, Publicerat paper (Fagfellevurdert)
Abstract [en]

During extraction of logging residues previous studies in Sweden have shown that up to 50% of the available logging residues will not reach the energy-conversion site. The remaining potential of the logging residues are therefore lost by handling either at the clear-felled site, during transportation or due to decomposition. An outtake of 100% is not possible or desired, since the Swedish Forest Agency recommends that at least 20% of the logging residues should be left at the clear-felled site after a fuel adapted logging operation. In this study the losses at the clear-felled area is examined by studying the distribution of the remaining logging residues under and between the harvester heaps as well amount of logging residues that are left at the roadside landing after comminution. The results show that most of the reaming logging residues are well distributed at the clear-felled area between the harvester heaps. Additional logging residues are left at the clear-felled area since the forwarder cannot gather all logging residues from under the harvester heaps. In addition to this a not insignificant amount of logging residues are left at the roadside landing.

sted, utgiver, år, opplag, sider
ETA-Florence Renewable Energies, 2015
Serie
European Biomass Conference and Exhibition, ISSN 2282-5819
Emneord
forest residues, forestry, harvesting
HSV kategori
Forskningsprogram
Teknik; Teknik, Skog och träteknik
Identifikatorer
urn:nbn:se:lnu:diva-49476 (URN)10.5071/23rdEUBCE2015-1CV.3.19 (DOI)000473718200054 ()9788889407516 (ISBN)
Konferanse
23rd European Biomass Conference 1-4 June 2015, Vienna Asutria
Tilgjengelig fra: 2016-02-01 Laget: 2016-02-01 Sist oppdatert: 2020-05-14bibliografisk kontrollert
Nilsson, B., Nilsson, D. & Thörnqvist, T. (2015). Distributions and Losses of Logging Residues at Clear-Felled Areas during Extraction for Bioenergy: Comparing Dried- and Fresh-Stacked Method. Forests, 6(11), 4212-4227
Åpne denne publikasjonen i ny fane eller vindu >>Distributions and Losses of Logging Residues at Clear-Felled Areas during Extraction for Bioenergy: Comparing Dried- and Fresh-Stacked Method
2015 (engelsk)Inngår i: Forests, ISSN 1999-4907, E-ISSN 1999-4907, Vol. 6, nr 11, s. 4212-4227Artikkel i tidsskrift (Fagfellevurdert) Published
Abstract [en]

It is well known that a large proportion of available logging residues intended for extraction will not reach the energy-conversion industry, because some are lost during transportation or left on the clear-felled area. However, there is little understanding of where logging residue losses occur in the supply chain. In this study, the distribution of logging residues for two methods (dried- and fresh-stacked method) to extract logging residues were studied in one clear-felled area. In addition, residue fractions were examined in a detailed comparison. Even though the fresh-stacked method left somewhat more logging residues at the clear-felled area, the differences are small between the methods. Approximately 30% of the total amount of logging residues was left behind between the harvester heaps, with an additional 10%-15% under these heaps and approximately 2%-3% beneath the windrows. The final product that was delivered to the energy-conversion industry was very similar, regardless of the extraction method used. The delivered chipped logging residues had moisture contents of 37% and 36% following fresh- and dried-stacked methods respectively, and in both cases the needle content in the processed logging residues was approximately 10%. However, the total amount of fine fractions (needles and fines) was slightly higher following dried-stacking.

Emneord
forest fuel, storage, quality, needles, moisture content, Norway spruce
HSV kategori
Forskningsprogram
Teknik, Skog och träteknik
Identifikatorer
urn:nbn:se:lnu:diva-48816 (URN)10.3390/f6114212 (DOI)000365704000022 ()2-s2.0-84949516879 (Scopus ID)
Tilgjengelig fra: 2016-01-19 Laget: 2016-01-15 Sist oppdatert: 2017-11-30bibliografisk kontrollert
Nilsson, D., Nilsson, B. & Thörnqvist, T. (2015). Nutrient removal after whole-tree harvesting with the traditional Swedish dried-stacked method for removal of logging residues. In: Obernberger I, Baxter D, Grassi A, Helm P (Ed.), Papers of the 23rd European Biomass Conference: Setting the course for a biobased economyExtracted from the Proceedings of the International Conference held in Viennna, Asutria1-4 June 2015. Paper presented at 23rd European Biomass Conference 1-4 June 2015, Vienna Asutria (pp. 9-13). ETA-Florence Renewable Energies
Åpne denne publikasjonen i ny fane eller vindu >>Nutrient removal after whole-tree harvesting with the traditional Swedish dried-stacked method for removal of logging residues
2015 (engelsk)Inngår i: Papers of the 23rd European Biomass Conference: Setting the course for a biobased economyExtracted from the Proceedings of the International Conference held in Viennna, Asutria1-4 June 2015 / [ed] Obernberger I, Baxter D, Grassi A, Helm P, ETA-Florence Renewable Energies , 2015, s. 9-13Konferansepaper, Publicerat paper (Fagfellevurdert)
Abstract [en]

Bioenergy from logging residues is an important contributor to Swedish energy supplies. Logging residues where long defined and regarded as the unmerchantable aboveground biomass left behind in the clear-felled area, consisting of branches, tops and small trees that are gathered after the round wood harvest, but logging residues are nowadays regarded as a third assortment next to timber and pulpwood with high economic value. However long-term experiments on removal of logging residues from Norway spruce (Picea abies (L.)Karst) stands have shown both growth reductions and growth increase in the next generation, because of decreasing amounts of nutrients. So an increased removal of logging residues requires some sort of compensation of nutrients. Therefore it is of importance to investigate how much nutrients that is removed from the stand after whole-tree harvesting.

In this study the removal of the nutrients nitrogen (N), phosphorus (P), calcium (Ca), potassium (K) and magnesium (Mg) have been investigated by laboratory analysis of the nutrients together with the actual removal of stemwood, bark and logging residues. The study has also investigated the distribution of nutrients at the clear-felled area.

The results show that approximately half of the total nutrient removed in whole tree harvesting is done with the removal of stemwood and bark. The results also show that approximately 30% of the total amount of nutrients is left at the clear-felled area.

sted, utgiver, år, opplag, sider
ETA-Florence Renewable Energies, 2015
Serie
European Biomass Conference and Exhibition Proceedings, ISSN 2282-5819
Emneord
forest residues, forestry, harvesting
HSV kategori
Forskningsprogram
Teknik; Teknik, Skog och träteknik
Identifikatorer
urn:nbn:se:lnu:diva-45865 (URN)10.5071/23rdEUBCE2015-1AO.1.2 (DOI)000473718200003 ()9788889407516 (ISBN)
Konferanse
23rd European Biomass Conference 1-4 June 2015, Vienna Asutria
Tilgjengelig fra: 2016-02-01 Laget: 2015-08-25 Sist oppdatert: 2020-05-14bibliografisk kontrollert
Trischler, J., Sandberg, D. & Thörnqvist, T. (2015). The potential of available biomass for energy purpose under changing conditions of environment and industry. In: Obernberger, I Baxter, D Grassi, A Helm, P (Ed.), PAPERS OF THE 23RD EUROPEAN BIOMASS CONFERENCE: SETTING THE COURSE FOR A BIOBASED ECONOMY. Paper presented at 23RD EUROPEAN BIOMASS CONFERENCE (pp. 266-269). ETA-FLORENCE RENEWABLE ENERGIES
Åpne denne publikasjonen i ny fane eller vindu >>The potential of available biomass for energy purpose under changing conditions of environment and industry
2015 (engelsk)Inngår i: PAPERS OF THE 23RD EUROPEAN BIOMASS CONFERENCE: SETTING THE COURSE FOR A BIOBASED ECONOMY / [ed] Obernberger, I Baxter, D Grassi, A Helm, P, ETA-FLORENCE RENEWABLE ENERGIES , 2015, s. 266-269Konferansepaper, Publicerat paper (Fagfellevurdert)
Abstract [en]

Wood is a lignocellulosic raw material that is used for a diversity of industrial products. Besides the traditional uses of wood in the construction, pulp- and papermaking and furniture industries, the energy recovery industry based on renewable resources such as wood has been growing strongly during recent years. Like all resources, wood is available only in limited amounts and an increasing demand leads to greater competition among the wood-using industries. By defining a strategic cube it was possible to visualise the impact of the different parameters on the types of wood raw material available. Further, the method supported estimations of the changes in the mix of wood raw materials when one or more of the parameters was changed. The results show that, in addition to the available land and to the climate conditions, the demands of the different sectors of wood-using industries have a strong impact on the amount of raw material available for energy purposes. Climate change and innovation or trends in the wood-using industries, for example, influence silvicultural management, and this then affects the mix of raw materials. The results challenge the studies estimating that large amounts of raw material available for energy purposes relate only to land.

sted, utgiver, år, opplag, sider
ETA-FLORENCE RENEWABLE ENERGIES, 2015
Emneord
competitiveness, forestry, market, production
HSV kategori
Forskningsprogram
Teknik, Bioenergiteknik/Energi- och Miljöteknik
Identifikatorer
urn:nbn:se:lnu:diva-94756 (URN)000473718200053 ()
Konferanse
23RD EUROPEAN BIOMASS CONFERENCE
Tilgjengelig fra: 2020-05-14 Laget: 2020-05-14 Sist oppdatert: 2020-05-14bibliografisk kontrollert
Trischler, J., Sandberg, D. & Thörnqvist, T. (2014). Estimating the Annual Above-Ground Biomass Production of Various Species on Sites in Sweden on the Basis of Individual Climate and Productivity Values. Forests, 5(10), 2521-2541
Åpne denne publikasjonen i ny fane eller vindu >>Estimating the Annual Above-Ground Biomass Production of Various Species on Sites in Sweden on the Basis of Individual Climate and Productivity Values
2014 (engelsk)Inngår i: Forests, ISSN 1999-4907, E-ISSN 1999-4907, Vol. 5, nr 10, s. 2521-2541Artikkel i tidsskrift (Fagfellevurdert) Published
Abstract [en]

The literature contains a large number of bioclimate, climate and biometric models for estimating the production of different species or stands under specific conditions on a defined site or models giving the distribution of a single species. Depending on the model used, the amount of input data required varies considerably and often involves a large investment in time and money. The purpose of this study was to create a model to estimate the annual above-ground biomass production of various species from site conditions defined by mean annual temperature and mean annual precipitation. For this approach, the Miami model of Lieth was used as a base model with some modifications. This first version of the modified model was restricted to sites in Sweden, where changes in the soil and groundwater level were relatively small, and where the growth of land vegetation was mostly dependent on temperature. A validation of this model has shown that it seems possible to use the Miami model to estimate the annual above-ground biomass production of various species, and that it was possible to compare the annual above-ground biomass production of different species on one site, as well as the annual above-ground biomass production of different species on different sites using the modeled data.

Emneord
MAT, MAP, bioclimatic model, above-ground biomass production
HSV kategori
Forskningsprogram
Teknik, Skog och träteknik
Identifikatorer
urn:nbn:se:lnu:diva-38556 (URN)10.3390/f5102521 (DOI)000344352900007 ()2-s2.0-84921412221 (Scopus ID)
Tilgjengelig fra: 2014-12-09 Laget: 2014-12-09 Sist oppdatert: 2017-12-05bibliografisk kontrollert
Trischler, J., Sandberg, D. & Thörnqvist, T. (2014). Evaluating the Competition of Lignocellulose Raw Materials for their Use in Particleboard Production, Thermal Energy Recovery, and Pulp- and Papermaking. BioResources, 9(4), 6591-6613
Åpne denne publikasjonen i ny fane eller vindu >>Evaluating the Competition of Lignocellulose Raw Materials for their Use in Particleboard Production, Thermal Energy Recovery, and Pulp- and Papermaking
2014 (engelsk)Inngår i: BioResources, ISSN 1930-2126, E-ISSN 1930-2126, Vol. 9, nr 4, s. 6591-6613Artikkel i tidsskrift (Fagfellevurdert) Published
Abstract [en]

There is increasing competition for raw materials between particleboard production, thermal energy recovery, and pulp-and papermaking. According to different scenarios, the consumption of lignocellulosic raw materials is increasing, which means that the competition is increasing. The primary production of lignocellulosic raw material in some regions may therefore reach the limit of sustainability; i.e., the lignocellulosic raw material must be used more efficiently to reduce the risk of a shortage. The physical and chemical properties of the lignocellulosic raw material of selected species have therefore been surveyed, and the raw material properties that are important for each of the three competitors have been defined. The aim of the study is to characterise the lignocellulosic raw materials according to the three competing users and to show whether they are high or low in competition. As methods, a relative ranking of the species regarding their raw material properties and regarding the requirements of the competitors as well as cluster analysis were chosen. The results show that the most favourable raw materials are from coniferous species, while monocotyledon species show an opposite trend.

Emneord
Wood using industry, Properties of raw material, Requirements for raw materials, Expression of competition
HSV kategori
Forskningsprogram
Teknik, Skog och träteknik
Identifikatorer
urn:nbn:se:lnu:diva-39133 (URN)000345396900066 ()2-s2.0-84911423135 (Scopus ID)
Tilgjengelig fra: 2015-01-15 Laget: 2015-01-15 Sist oppdatert: 2019-08-27bibliografisk kontrollert
Blom, Å. & Thörnqvist, T. (2014). Live storage and drying of storm-felled Norwayspruce (Picea abies, L. Karst.) and Scots pine (Pinussylvestris L.) trees. Wood Material Science & Engineering, 9(4), 209-213
Åpne denne publikasjonen i ny fane eller vindu >>Live storage and drying of storm-felled Norwayspruce (Picea abies, L. Karst.) and Scots pine (Pinussylvestris L.) trees
2014 (engelsk)Inngår i: Wood Material Science & Engineering, ISSN 1748-0272, E-ISSN 1748-0280, Vol. 9, nr 4, s. 209-213Artikkel i tidsskrift (Fagfellevurdert) Published
Abstract [en]

Storm-felled trees left in the forest for a shorter or longer period, affect the quality of the logs. The change in quality ismainly because of attack of fungi and insects, which in turn depends on the moisture content (MC) of the sapwood. Thepurpose of this study was to receive more knowledge about drying of storm-felled trees by investigating how fast winterstorm-felled Norway spruce and Scots pine dried when left in the forest. Sixteen storm-felled spruces with part of the rootsstill in ground contact were selected from three stands and in addition to 10 pines from one of the stands. The trees wereexamined for MC in the sapwood until 21 months after the storm. This study indicates that wind-thrown trees with rootsstill connected to the soil can survive one summer without any value loss caused by draught, fungi and insects. The standconditions can be of importance as the storm-felled trees in the stand, with scattered windthrow, were in best condition afterone year, as they were shadowed by the trees still standing. Comparing spruces and pines with the stand with scatteredwindthrow, pines were more sensitive to drought and reached critical MC earlier.

HSV kategori
Forskningsprogram
Teknik, Skog och träteknik
Identifikatorer
urn:nbn:se:lnu:diva-19006 (URN)10.1080/17480272.2014.881914 (DOI)2-s2.0-84911384320 (Scopus ID)
Tilgjengelig fra: 2012-05-29 Laget: 2012-05-29 Sist oppdatert: 2020-05-20bibliografisk kontrollert
Organisasjoner
Identifikatorer
ORCID-id: ORCID iD iconorcid.org/0000-0003-2860-7587