| 1. |
- Arshadi, Mehrdad, et al.
(författare)
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Comparison of fatty and resin acid composition in boreal lodgepole pine and Scots pine for biorefinery applications
- 2013
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Ingår i: Industrial Crops and Products. - : Elsevier BV. - 0926-6690 .- 1872-633X. ; 49, s. 535-541
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Tidskriftsartikel (refereegranskat)abstract
- To investigate the potential for Scots- and lodgepole pine for biorefinery applications such as e.g., biodiesel and glue production, wood samples from five different sites in northern Sweden were compared. 21 fatty and 10 resin acids were detected by extraction and GC MS analysis. Total fatty- and resin acid contents of Scots pine varied between 2.4 and 41.4 mg/g. Corresponding concentrations for lodgepole pine were 23 and 26.0 mg/g of dry material. Multivariate models were made with principal component analysis to take advantage of the multivariate correlations between the individual acids. Wood tissue type explained most of the variation in fatty and resin acid content, with heartwood having up to five times the extractive concentration of sapwood. Resin acids were mainly associated with heartwood, while fatty acids were more associated with sapwood. A five-component PLSDA-model distinguished between the two species, mainly due to differences in their hexadecanoic and heptadecanoic acid contents. Heartwood from Scots pine is more suitable for resin extraction while lodgepole pine is a better option for fatty- and resin acid extraction because of the extractives' evenly distribution between wood types. Around 150 kg of fatty acids and 1 ton of resins can be harvested per hectare from a typical mature boreal lodgepole pine stand, for biorefinery use. Systematic fractionation and selection of heartwood and sapwood will likely optimize industrial applications (e.g. biodiesel production) of each fraction. (C) 2013 Elsevier B.V. All rights reserved.
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| 2. |
- Backlund, Ingegerd, et al.
(författare)
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Biomass Production of Dense Direct-Seeded Lodgepole Pine (Pinus contorta) at Short Rotation Periods
- 2012
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Ingår i: Silva Fennica. - : Finnish Society of Forest Science. - 0037-5330 .- 2242-4075. ; 46, s. 609-623
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Tidskriftsartikel (refereegranskat)abstract
- Backlund, I. & Bergsten, U. 2012. Biomass production of dense direct-seeded lodgepole pine (Pinus contorta) at short rotation periods. Silva Fennica 46(4): 609-623. Lodgepole pine (Pinus contorta) is a fast-growing species that is suitable for producing woody biomass in Nordic countries. Direct seeding of this species is cheaper than planting and creates dense, stable stands. The objective of this study was to quantify the stem volume and biomass production of direct seeded lodgepole pine stands grown under different site conditions with different stem densities, at an age that would permit extensive harvesting of biomass. A circle-plot inventory was performed in 16 of the oldest direct seeded lodgepole pine stands in mid-northern Sweden. Stemwood production of almost 200 m(3)/ha was achieved on average on the best sites, rising to about 300 m(3)/ha for the best circle-plots within 30 years of direct seeding despite the fact that pre-commercial thinning was made once or twice. This corresponds to 100 and 140 tons of dry weight biomass/ha, respectively. Higher stand stem densities (>= 3000 st/ha) yielded more biomass with only slight reductions in diameter at breast height. The development of stem volume with respect to dominant height in direct seeded stands was becoming comparable to that in planted stands with similar spacing. It therefore seems that there is an unutilized potential for cost-effectively growing lodgepole pine in dense stands for biomass production after direct seeding. It may be possible to devise regimes for short(er) rotation forestry that would yield substantial amount of inexpensive biomass for biorefineries within a few decades.
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| 3. |
- Backlund, Ingegerd, et al.
(författare)
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Biorefinery product potentials using tree biomass as feedstock - A survey on opportunities and threats to the new wood products industry
- 2014
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Ingår i: Biomass and Bioenergy. - : Elsevier BV. - 0961-9534 .- 1873-2909. ; 70, s. 207-216
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Tidskriftsartikel (refereegranskat)abstract
- A questionnaire survey on the potential of biorefinery products was carried out along with an analysis of energy prices and wood assortments. Electricity production was considered to have the potential for the highest investment return over ten years, followed by solid wood products, bioenergy assortments and textiles. Only pulp and paper were perceived as returning lower potential investment values over the next ten years than over the next five. Of the survey respondents, 95% believed that the value of woody biomass will increase over the next ten years, mainly through its replacement of oil-based products, although there will be problems due to lack of suitable raw material. A wide range of chemical products were described but a greater confidence in more traditional solid fuel products still prevails. Stemwood is the most favored part of the tree with only a few respondents saying that they wanted specific chemicals extracted. The electricity price and wood fuel price were found to be strongly correlated and 91% of respondents said their products would be affected by the electricity price. Electricity prices within OECD countries are expected to increase by 15% from 2011 to 2035, with wood fuel prices increasing by roughly 10% during the same period. Therefore, the electricity price could become a decisive factor in the future use of biomass in biorefineries. Our results suggest that large-scale commercial biorefinery production will soon be possible but new wood assortment classifications are needed that include both fiber properties and chemical properties such as extractive content.
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| 4. |
- Backlund, Ingegerd
(författare)
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Cost-effective cultivation of lodgepole pine for biorefinery applications
- 2013
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The overall objective was to evaluate the scope for the cost-effective cultivation of lodgepole pine (Pinus contorta, PC) stands in a way that would enable early biomass harvesting to supply raw material for biorefineries. Commercial direct seeded PC stands were shown to produce 200 m3/ha of stemwood or 100 tons of d.w. biomass within 30 years despite one or two pre-commercial thinnings. Higher stand stem densities (≥3000 st/ha) yielded even more biomass (ca. 300 m3/ha) with only slight reductions in DBH (Study I). The effects of different silvicultural regimes on 20-year-old direct seeded PC stands were analyzed in a field experiment. A high biomass regime (no PCT) produced 144% more biomass and 134% more stem volume than the conventional regime (2200 st/ha). The diameter of the 1000 largest trees/ha did not differ between regimes. A regime with 4500 st/ha gave promising results in terms of both biomass and timber production. Importantly, producing large amounts of biomass early in the rotation period is compatible with a subsequent change of focus to emphasize pulp and timber production (II). To investigate the potential for using PC biomass in biorefineries to produce e.g. liquid biofuels, the chemical contents of wood samples from Scots- and lodgepole pine trials were compared. Heartwood had up to five times greater extractive contents than sapwood. 21 fatty and 10 resin acids were detected. It was estimated that ca. 150 kg of fatty acids and 1 ton resins/ha could be harvested from a mature boreal PC stand (III). The chemical compounds in the aboveground fractions of PC trees grown under a direct seeding-based regime were identified. The bark provided the highest extractive yields (16%) and the stemwood the lowest (1%). The extractive profiles of the needles differed strongly from the other fractions, being particularly rich in wax esters and fatty alcohols. It should be possible to harvest 2-3 tons of crude extractives/ha from a dense 30-year-old PC stand (IV). To estimate the commercial potential of different biorefinery products, a survey was performed. 95% of the respondents believed that the value of tree biomass will increase over the next ten years, mainly due to the replacement of oil-based products. Key product categories were: transportation fuels, special celluloses, materials and plastics, solid fuels and specialty chemicals. A strong correlation between the prices of electricity and wood fuel was identified, and electricity prices may play a key role in determining the future use of biomass (V). Overall, there is considerable but currently unrealized potential for the cost-effective cultivation of lodgepole pine in directly seeded dense stands using short rotation periods to produce substantial quantities of biomass for biorefineries within only a few decades.
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| 5. |
- Backlund, Ingegerd, et al.
(författare)
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Extractive profiles of different lodgepole pine (Pinus contorta) fractions grown under a direct seeding-based silvicultural regime
- 2014
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Ingår i: Industrial Crops and Products. - : Elsevier BV. - 0926-6690 .- 1872-633X. ; 58, s. 220–229-
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Tidskriftsartikel (refereegranskat)abstract
- The aim of this study was to identify and quantify the chemical compounds in the aboveground fractions of lodgepole pine trees (stem top, stem base, bark, branches, needles and cones) grown under a direct seeding-based silvicultural regime, including per hectare-outputs and industrial applications. Plant metabolites were extracted from trees of two sizes from two areas of central-northern Sweden with different climates and analysed by GC MS. The stands were 30 years old and had undergone pre-commercial thinning. The extractive yields for the fractions differed significantly, with the bark having the highest yields (13-20%) and the stem the lowest (0.5-3.5%). Multivariate analysis showed that the extractive profiles of the needles deviated strongly from those of the other fractions, with the needles being particularly rich in wax esters and fatty alcohols. The stemwood mainly contained ketones, terpenes and acids. The cones had a prominent pine scent and were rich in aromatics. The stands examined in this study could produce large quantities of biomass suitable for use in biorefineries without any change in their current management regimes, yielding 2-3 tonnes of crude extractives per hectare. The precise extractive yield depends on the site fertility, tree partitioning and tree size. The extractives obtained can be used for production of, e.g. biodiesel, glue, bioactive food additives, cosmetics, and polymer precursors. Lodgepole pine can be cultivated cost-effectively by direct seeding in dense stands, and advantageously harvested to produce biomass and extractives. It is therefore an appropriate species for the production of biorefinery feedstocks in the boreal region. (C) 2014 Elsevier B.V. All rights reserved.
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| 6. |
- Steneberg, Pär, et al.
(författare)
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Hyperinsulinemia Enhances Hepatic Expression of the Fatty Acid Transporter Cd36 and Provokes Hepatosteatosis and Hepatic Insulin Resistance
- 2015
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Ingår i: Journal of Biological Chemistry. - 0021-9258 .- 1083-351X. ; 290:31, s. 19034-19043
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Tidskriftsartikel (refereegranskat)abstract
- Hepatosteatosis is associated with the development of both hepatic insulin resistance and Type 2 diabetes. Hepatic expression of Cd36, a fatty acid transporter, is enhanced in obese and diabetic murine models and human nonalcoholic fatty liver disease, and thus it correlates with hyperinsulinemia, steatosis, and insulin resistance. Here, we have explored the effect of hyperinsulinemia on hepatic Cd36 expression, development of hepatosteatosis, insulin resistance, and dysglycemia. A 3-week sucrose-enriched diet was sufficient to provoke hyperinsulinemia, hepatosteatosis, hepatic insulin resistance, and dysglycemia in CBA/J mice. The development of hepatic steatosis and insulin resistance in CBA/J mice on a sucrose-enriched diet was paralleled by increased hepatic expression of the transcription factor Ppar gamma and its target gene Cd36 whereas that of genes implicated in lipogenesis, fatty acid oxidation, and VLDL secretion was unaltered. Additionally, we demonstrate that insulin, in a Ppar gamma-dependent manner, is sufficient to directly increase Cd36 expression in perfused livers and isolated hepatocytes. Mouse strains that display low insulin levels, i.e. C57BL6/J, and/or lack hepatic Ppar gamma, i.e. C3H/HeN, do not develop hepatic steatosis, insulin resistance, or dysglycemia on a sucrose-enriched diet, suggesting that elevated insulin levels, via enhanced CD36 expression, provoke fatty liver development that in turn leads to hepatic insulin resistance and dysglycemia. Thus, our data provide evidence for a direct role for hyperinsulinemia in stimulating hepatic Cd36 expression and thus the development of hepatosteatosis, hepatic insulin resistance, and dysglycemia.
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| 7. |
- Ulvcrona, Kristina, et al.
(författare)
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Beslutsstöd för produktion av biomassa och uttag av bioenergi i unga skogar : slutrapport till Energimyndigheten(2011-003472) och Skogssällskapet [1112-95/154-10; LOMOL]
- 2015
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- I Sverige finns stora arealer av täta ungskogar (”eftersatta röjningar”) i vilka skörd av biomassa i form av bränslesortiment kan bidra med ett betydande energitillskott. Det har dock saknats ett konkret kunskapsunderlag för utveckling av praktiska skötselinstruktioner, de s.k. gallringsmallar som till viss del används härrör från 1960-talet och avser enbart stamved. I projektet har därför en kunskapssammanställning tagits fram som kan tillämpas vid uttag av biomassa/bioenergisortiment i stamtäta unga bestånd. Vi kan nu bättre prognostisera (i) beståndsutveckling vid olika skötsel, (ii) möjliga/lämpliga uttagsnivåer vid olika beståndshöjd och stamantal, (iii) ev. tillväxteffekter orsakade av näringsbortfall vid uttag av biomassa och (iv) tillväxt över tiden för träd som står kvar efter ett första biomassauttag. Grund för arbetet har varit ett stort antal fältförsök som är följda upp till närmare 50 år. Långsiktigheten och upplösningen i dessa försök gör att vi bedömer att vår sammanställning kan fungera som ett beslutsstöd angående val av skötselåtgärd för den unga skogen samt val av tidpunkt och uttagsnivå vid ett tidigt uttag av bioenergi. En viktig faktor vid valet av åtgärd är kostnaden för ett tidigt biomassauttag. Därför har vi även kvantifierat kostnadseffektiviteten för de nya tekniska skördelösningar som är på väg, och som kan möjliggöra ett rationellt uttag av bioenergisortiment redan vid den första gallringen, och kalkylerat ekonomiskt utfall för olika skötselregimer. Projektresultaten bör utgöra en grund för att ta fram ett verktyg för val av åtgärd i täta unga skogar.
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| 8. |
- Ulvcrona, Kristina, et al.
(författare)
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Comparison of silvicultural regimes of lodgepole pine (Pinus contorta) in Sweden 5 years after precommercial thinning
- 2013
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Ingår i: Silva Fennica. - : Finnish Society of Forest Science. - 0037-5330 .- 2242-4075. ; 47
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Tidskriftsartikel (refereegranskat)abstract
- Early effects (stem volume, mean diameter at breast height weighted against basal area (Dgv) (Dgv), biomass and damage frequency) of different silvicultural regimes 18-19 years after direct seeding of lodgepole pine in northern Sweden were analysed. A Conventional regime, (i) precommercial thinning (PCT) to 2 200 stems ha-1, was compared to: (ii) High biomass production (15300 stems ha-1, no PCT) with and without corridor thinning at year 20, (iii) production of Large dimension trees (PCT to 1 700 stems ha-1), (iv), Combined high biomass production and production of conventional round wood (PCT to 4 500 stems ha-1). PCT was done 15 yrs after direct seeding for all PCT treatments. Local biomass functions showed that the regimes aiming at High biomass production displayed ca 144-157% more biomass and 134-143% more stem volume than the Conventional and Large dimension regimes (ca 21 tons and 31 m3 ha-1). Dgv for the 1 000 (9.2 cm) and 2 000 (8.3 cm) largest trees ha-1 appeared unaffected by regime. By schematic corridor thinning (70% of the total area) at year 20 in the High biomass regime, 27-32 tons of biomass ha-1 and 38-45 m3 ha-1 could be derived while still having a Dgv of the 1 000 largest trees ha-1 of about 8 cm. Therefore, this study indicates that it is possible to produce and harvest large amounts of biomass and stem volume early in the rotation period without excluding later pulp and timber production. This initial regime comparison should be continued over time.
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