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  • 1. Ahman, Birgitta
    et al.
    Svensson, Kristin
    Rönnegård, Lars
    Dalarna University, School of Technology and Business Studies, Statistics.
    High female mortality resulting in herd collapse in free-ranging domesticated reindeer (Rangifer tarandus tarandus) in Sweden2014In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 9, no 10, article id e111509Article in journal (Refereed)
    Abstract [en]

    Reindeer herding in Sweden is a form of pastoralism practised by the indigenous Sami population. The economy is mainly based on meat production. Herd size is generally regulated by harvest in order not to overuse grazing ranges and keep a productive herd. Nonetheless, herd growth and room for harvest is currently small in many areas. Negative herd growth and low harvest rate were observed in one of two herds in a reindeer herding community in Central Sweden. The herds (A and B) used the same ranges from April until the autumn gathering in October-December, but were separated on different ranges over winter. Analyses of capture-recapture for 723 adult female reindeer over five years (2007-2012) revealed high annual losses (7.1% and 18.4%, for herd A and B respectively). A continuing decline in the total reindeer number in herd B demonstrated an inability to maintain the herd size in spite of a very small harvest. An estimated breakpoint for when herd size cannot be kept stable confirmed that the observed female mortality rate in herd B represented a state of herd collapse. Lower calving success in herd B compared to A indicated differences in winter foraging conditions. However, we found only minor differences in animal body condition between the herds in autumn. We found no evidence that a lower autumn body mass generally increased the risk for a female of dying from one autumn to the next. We conclude that the prime driver of the on-going collapse of herd B is not high animal density or poor body condition. Accidents or disease seem unlikely as major causes of mortality. Predation, primarily by lynx and wolverine, appears to be the most plausible reason for the high female mortality and state of collapse in the studied reindeer herding community.

  • 2.
    Berglund, Torkel
    et al.
    Kungliga Tekniska högskolan.
    Borg-Karlsson, Anna Karin
    Kungliga Tekniska högskolan.
    Lindström, Anders
    Dalarna University, School of Technology and Business Studies, Forest and Wood Technology.
    Ohlsson, Anna
    Kunliga Tekniska högskolan.
    Hellqvist, Claes
    Dalarna University, School of Technology and Business Studies, Forest and Wood Technology.
    Slutrapport, fält- och laboratorietest av substanser för aktivering av det egna försvaret hos gran- och tallplantor2012Report (Other academic)
  • 3.
    Berglund, Torkel
    et al.
    KTH.
    Lindström, Anders
    Dalarna University, School of Technology and Business Studies, Forest and Wood Technology.
    Aghelpasand, Hooman
    KTH.
    Stattin, Eva
    Dalarna University, School of Technology and Business Studies, Forest and Wood Technology.
    Ohlsson, Anna B.
    KTH.
    Protection of spruce seedlings against pine weevil attacks by treatment of seeds or seedlings with nicotinamide, nicotinic acid and jasmonic acid2016In: Forestry (London), ISSN 0015-752X, E-ISSN 1464-3626, Vol. 89, no 2, p. 127-135Article in journal (Refereed)
    Abstract [en]

    Sustainable methods are required to protect newly planted tree seedlings from insect herbivore attack. To this end, here Norway spruce (Picea abies (L.) Karst.) seeds were treated with 2.5 mM nicotinamide (NIC), 2.5 mM nicotinic acid (NIA), 3 mM jasmonic acid (JA) or 0.2 mM 5-azacytidine (5-Aza), and 6-month-old seedlings grown from these seeds were planted at a reforestation area in central Sweden. Attack by pine weevils (Hylobius abietis) was reduced by 50 per cent by NIC treatment, 62.5 per cent by JA treatment and 25 per cent by 5-Aza treatment, when compared with seedlings grown from untreated seeds. Watering 18-month-old spruce seedlings with 2 mM NIC or 2 mM NIA did reduce attack during the first season in the field by 40 and 53 per cent, respectively, compared with untreated plants. Girdling was also reduced by the different treatments. Analysis of conifer seedlings treated with 5-Aza points at a possible involvement of epigenetic mechanisms in this defensive capacity. This is supported by a reduced level of DNA methylation in the needles of young spruce seedlings grown in a greenhouse from NIC-treated seeds. Seed treatment for seedling defense potentiation is simple, inexpensive and also a new approach for forestry with many potential applications.

  • 4.
    Blomberg, Jonas
    Dalarna University, School of Technology and Business Studies, Materials Technology.
    Elastic strain at semi-isostatical compression of Scots pine (pinus sylvestris L.)2005In: Journal of Wood Science, ISSN 1435-0211, E-ISSN 1611-4663, Vol. 51, no 4, p. 401-404Article in journal (Refereed)
    Abstract [en]

    Quarter-sawn and plain-sawn specimens of Scots pine were semi-isostatically compressed at 5, 15, 50, and 140MPa in a Quintus press. Elastic strain was measured using a telescope device that was pushed together when wood was compressed and remained in this position at release of pressure. Delayed elastic and plastic strains were assessed through repeated callipering during 5 years after densification. At 140MPa, wood reached an almost compact structure (rho approximate to 1450kg/m(3)) but as a result of elastic springback the density decreased to just below 1000kg/m(3). At 140MPa, the elastic and delayed elastic strains were 14.6% and 1.8%, respectively, in quarter-sawn specimens, and were 13.1% and 0.8%, respectively, in plain-sawn specimens. The higher elastic strains in quarter-sawn specimens can be attributed to elastic springback in the tangentially deformed latewood bands.

  • 5.
    Blomberg, Jonas
    et al.
    Dalarna University, School of Technology and Business Studies, Wood Technology.
    Persson, Bengt
    Dalarna University, School of Technology and Business Studies, Wood Technology.
    An algorithm for comparing density in CT-images taken before and after compression of Pinus sylvestris2005In: European Journal of Wood and Wood Products, ISSN 0018-3768, E-ISSN 1436-736X, Vol. 63, no 1, p. 23-29Article in journal (Refereed)
    Abstract [en]

    Ten plain-sawn boards of Scots pine (Pinus sylvestris L.) were compressed semi-isostatically according to the CaLignum process in a Quintus press at 25 C and 140 MPa. X-ray computerised tomography images of the same cross-sections were captured before and after compression and compared using a transformation algorithm. In the algorithm the shape of compressed cross-sections were converted to the same shape as non-compressed using the density variation between pixels. Density after compression and the increase in density were analysed using PLS regression. The regressor variables described position in the cross-section and wood properties of each pixel. Heartwood and other resinous wood were less compressed than sapwood, particularly in boards with high resin content. Density also increased little close to the press table, especially in whorls with large knots. Higher original density gives lower degree of compression but still higher density after compression.

  • 6.
    Blomberg, Jonas
    et al.
    Dalarna University, School of Technology and Business Studies, Wood Technology.
    Persson, Bengt
    Dalarna University, School of Technology and Business Studies, Wood Technology.
    Plastic deformation in small clear pieces of Scots Pine (Pinus sylvestris L.) during densification with the Calignum® process2004In: Journal of Wood Science, ISSN 1435-0211, E-ISSN 1611-4663, Vol. 50, no 4, p. 307-314Article in journal (Refereed)
  • 7.
    Blomberg, Jonas
    et al.
    Dalarna University, School of Technology and Business Studies, Forest and Wood Technology.
    Persson, Bengt
    Dalarna University, School of Technology and Business Studies, Forest and Wood Technology.
    Swelling pressure of semi-isostatically densified wood under different mechanical restraints2007In: Wood Science and Technology, ISSN 0043-7719, E-ISSN 1432-5225, Vol. 41, no 5, p. 401-415Article in journal (Refereed)
    Abstract [en]

    Semi-isostatically densified and native wood samples of Scots pine and European birch were soaked in water. The swelling coefficients as well as the swelling pressure, that arose when the specimens were restrained in some way prior to the swelling, were measured using a universal testing machine equipped with a high resolution load-cell and an external extensometer. As densified wood swells, the native structure is almost restored and the swelling pressure became twice as high as for native wood in the most compressed directions (radial for pine and birch). That cell-shape recovery increases the swelling pressure can explain the problems with imbalance in laminated constructions where densified wood is used. The possibility to predict the swelling pressure from basic material properties was evaluated. The correlations between swelling pressure and material properties were strong enough to yield good predictive models.

  • 8. Boonstra, M. J.
    et al.
    Blomberg, Jonas
    Dalarna University, School of Technology and Business Studies, Forest and Wood Technology.
    Semi-isostatic densification of heat-treated radiata pine2007In: Wood Science and Technology, ISSN 0043-7719, E-ISSN 1432-5225, Vol. 41, no 7, p. 607-617Article in journal (Refereed)
    Abstract [en]

    Semi-isostatic densification is a useful method to increase the density and to improve the mechanical properties of fast-grown softwood species like radiata pine. A major disadvantage of this method is the almost complete recovery of the original dimensions when densified wood is exposed to moisture. Heat treatment improves the dimensional stability of wood and might be a useful method to prevent this shape-recovery after densification. However, no or only a limited effect on the shape-recovery was found when densified radiata pine was exposed to moisture.

  • 9. Brännström, Mattias
    et al.
    Westin, Jerker
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    Classification of structural timber by decision trees: a comparison to the certified method2009In: Forest products journal, ISSN 0015-7473, Vol. 59, no 3, p. 53-61Article in journal (Refereed)
    Abstract [en]

    This work is an example of how to adapt a classification method, in this case a classification tree, to the present standardized method for the development of settings for strength grading machines. Data from commercially available industrial strength grading equipment were used on a large sample (approximately 1440 pieces) of Norway spruce (Picea abies (L. Karsten)) in various sawn dimensions. The equipment is a multisensor scanning device combining planar X-ray and resonance frequency measurement. Destructive testing was done according to European standard EN408. The goal was to make the classification, based on machine data, as close as possible to the optimum grading, which was done according to standard. Two different approaches for classification by cost-sensitive decision trees were applied to the data and compared to classification accredited according to EN14081. Classification accuracy increased from 64% correctly classified to 73%, and a reduction from 33% False Negative to 23% was achieved. False Positive increased from 3% to 4%. The outcome was an increase in value for the producer by 0.9%–2.1% at 2007 average price level. The improvement came mainly from an in-yield increase in C30 by 10%.

  • 10.
    Chiatante, Donato
    et al.
    Università degli Studi dell'Insubria.
    Radoglou, Kalliopi
    Democritus University of Thrace.
    Sismanis, Nikos
    Democritus University of Thrace.
    Smirnakou, Sonia
    Democritus University of Thrace.
    Mattsson, Anders
    Dalarna University, School of Technology and Business Studies, Forest and Wood Technology.
    Hernandez Velasco, Marco
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Schirone, Bartolomeo
    Universita degli Studi della Tuscia.
    Marras, Tatiana
    Universita degli Studi della Tuscia.
    Mechilli, Manuela
    Universita degli Studi della Tuscia.
    Ortolani, Maria Raffaella
    Universita degli Studi della Tuscia.
    Vessella, Federico
    Universita degli Studi della Tuscia.
    Terzaghi, Mattia
    Università degli Studi dell'Insubria.
    Fulgaro, Nicoletta
    Università degli Studi dell'Insubria.
    Montagnoli, Antonio
    Università degli Studi dell'Insubria.
    Càtia, Freitas
    Azorina S.A.
    Pietrzak, Malgorzata
    Azorina S.A.
    Casimiro, Pedro
    Azorina S.A.
    Ferreira, Raquel
    Azorina S.A.
    ZEPHYR Project – Deliverable D3.3: Final report on growth tests and biological validation2015Report (Other academic)
  • 11.
    Felleki, Majbritt
    Dalarna University, School of Technology and Business Studies, Statistics. Swedish University of Agricultural Sciences.
    Genetic Heteroscedasticity for Domestic Animal Traits2014Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Animal traits differ not only in mean, but also in variation around the mean. For instance, one sire’s daughter group may be very homogeneous, while another sire’s daughters are much more heterogeneous in performance. The difference in residual variance can partially be explained by genetic differences. Models for such genetic heterogeneity of environmental variance include genetic effects for the mean and residual variance, and a correlation between the genetic effects for the mean and residual variance to measure how the residual variance might vary with the mean.

    The aim of this thesis was to develop a method based on double hierarchical generalized linear models for estimating genetic heteroscedasticity, and to apply it on four traits in two domestic animal species; teat count and litter size in pigs, and milk production and somatic cell count in dairy cows.

    The method developed is fast and has been implemented in software that is widely used in animal breeding, which makes it convenient to use. It is based on an approximation of double hierarchical generalized linear models by normal distributions. When having repeated observations on individuals or genetic groups, the estimates were found to be unbiased.

    For the traits studied, the estimated heritability values for the mean and the residual variance, and the genetic coefficients of variation, were found in the usual ranges reported. The genetic correlation between mean and residual variance was estimated for the pig traits only, and was found to be favorable for litter size, but unfavorable for teat count.

  • 12.
    Felleki, Majbritt
    et al.
    Dalarna University, School of Technology and Business Studies, Statistics.
    Lee, Dongwhan
    Department of Statistics, Seoul National University, Seoul 151-747, Korea .
    Lee, Youngjo
    Department of Statistics, Seoul National University, Seoul 151-747, Korea .
    Gilmour, Arthur R.
    School of Mathematics and Applied Statistics, Faculty of Informatics, University of Wollongong, Wollongong, NSW 2522, Australia.
    Rönnegård, Lars
    Dalarna University, School of Technology and Business Studies, Statistics.
    Estimation of breeding values for mean and dispersion, their variance and correlation using double hierarchical generalized linear models2012In: Genetics Research, ISSN 0016-6723, Vol. 94, no 6, p. 307-317Article in journal (Refereed)
    Abstract [en]

    The possibility of breeding for uniform individuals by selecting animals expressing a small response to environment has been studied extensively in animal breeding. Bayesian methods for fitting models with genetic components in the residual variance have been developed for this purpose, but have limitations due to the computational demands. We use the hierarchical (h)-likelihood from the theory of double hierarchical generalized linear models (DHGLM) to derive an estimation algorithm that is computationally feasible for large datasets. Random effects for both the mean and residual variance parts of the model are estimated together with their variance/covariance components. An important feature of the algorithm is that it can fit a correlation between the random effects for mean and variance. An h-likelihood estimator is implemented in the R software and an iterative reweighted least square (IRWLS) approximation of the h-likelihood is implemented using ASReml. The difference in variance component estimates between the two implementations is investigated, as well as the potential bias of the methods, using simulations. IRWLS gives the same results as h-likelihood in simple cases with no severe indication of bias. For more complex cases, only IRWLS could be used, and bias did appear. The IRWLS is applied on the pig litter size data previously analysed by Sorensen & Waagepetersen (2003) using Bayesian methodology. The estimates we obtained by using IRWLS are similar to theirs, with the estimated correlation between the random genetic effects being −0·52 for IRWLS and −0·62 in Sorensen & Waagepetersen (2003).

  • 13.
    Felleki, Majbritt
    et al.
    Dalarna University, School of Technology and Business Studies, Statistics. Sveriges Lantbruksuniversitet.
    Lundeheim, Nils
    Sveriges Lantbruksuniversitet.
    Genetic Control of Residual Variance for Teat Number in Pigs2013In: Proc. Assoc. Advmt. Anim. Breed. Genet., AAABG , 2013, p. 538-541Conference paper (Other academic)
    Abstract [en]

    The genetic improvement in litter size in pigs has been substantial during the last 10-15 years. The number of teats on the sow must increase as well to meet the needs of the piglets, because each piglet needs access to its own teat. We applied a genetic heterogeneity model on teat numberin sows, and estimated medium-high heritability for teat number (0.5), but low heritability for residual variance (0.05), indicating that selection for reduced variance might have very limited effect. A numerically positive correlation (0.8) between additive genetic breeding values for mean and for variance was found, but because of the low heritability for residual variance, the variance will increase very slowly with the mean.

  • 14.
    Felleki, Majbritt
    et al.
    Dalarna University, School of Technology and Business Studies, Statistics.
    Lundeheim, Nils
    Sveriges lantbruksuniversitet, Institutionen för husdjursgenetik.
    Genetic Heteroscedasticity for Teat Count in PigsManuscript (preprint) (Other academic)
  • 15.
    Felleki, Majbritt
    et al.
    Dalarna University, School of Technology and Business Studies, Statistics.
    Lundeheim, Nils
    SLU.
    Genetic heteroscedasticity of teat count in pigs2015In: Journal of Animal Breeding and Genetics, ISSN 0931-2668, E-ISSN 1439-0388, Vol. 132, no 5, p. 392-398Article in journal (Refereed)
    Abstract [en]

    The genetic improvement in pig litter size has been substantial. The number of teats on the sowmust thus increase as well to meet the needs of the piglets, because each piglet needs access to itsown teat. We applied a genetic heterogeneity model to teat counts in pigs, and estimated a mediumheritability for teat counts (0.35), but found a low heritability for residual variance (0.06),indicating that selection for reduced residual variance might have a limited effect. A numericallypositive correlation (0.8) was estimated between the breeding values for the mean and the residualvariance. However, because of the low heritability of the residual variance, the residual variance will probably increase very slowly with the mean.

  • 16.
    Gullberg, Tomas
    et al.
    Dalarna University, School of Technology and Business Studies, Business Administration and Management.
    Johansson, Jerry
    Dalarna University, School of Technology and Business Studies, Business Administration and Management.
    A method for integrated extraction of logging residues and soil scarification on a small scale2006In: Biomass and Bioenergy, ISSN 0961-9534, E-ISSN 1873-2909, Vol. 30, no 12, p. 1035-1042Article in journal (Refereed)
    Abstract [en]

    A new method for integrated haulage of logging residues and soil scarification on a small-scale has been evaluated. The base machine was a farm tractor to which a grapple loader trailer was attached. The grapple loader had an attachment on the grapple used for the integrated recovery of forest energy from logging residues and soil scarification. The machine was in this case, when hauling the logging residues fresh, also used for hauling round wood. It may even be used for, e.g. spreading wood ashes (only simulated). Conventional machine systems with special machines for all four types of work result in very high fixed costs for moving, etc. which makes cost unacceptable for many small sites. Effective time per dry ton of logging residues was 28.4min in the integrated method, of which soil scarification was 14.3min. Average load size was about 1.3ton dry matter (about 2.9m3 solid). The soil scarification plots covered 12% of the surface. Cost calculations show that the integration of several activities results in substantially lower costs for small harvesting sites. For sites of about 1.5ha the cost is about the same as for conventional machines. The studied method creates new possibilities for self-employed forest owners to do the work themselves and, in case of lower personal cost and no moving cost, reduce cost further.

  • 17.
    Hernandez Velasco, Marco
    et al.
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Kotilainen, Titta
    Valoya Ltd.
    New technology for pre-cultivation of forest seedlings under LED lamps – modification of light conditions to mitigate light shock stress after transplanting to open land2014In: 2nd Restoring Forests Conference Abstracts, 2014Conference paper (Other academic)
    Abstract [en]

    Forest restoration aims to cope with the increasing demand on forest products, as well as an aid in fighting climate change and compensating for accelerated deforestation. Funded by the European Commission under the Seventh Framework Program (FP7), the Zephyr project aims to introduce a zero-impact incubator for the pre-cultivation of forest regeneration materials. The consortium, involving 14 organizations of 10 different European countries, is developing innovative and cost-efficient technologies that will allow the production of standardized high quality forest seedlings ready to be transplanted. The technologies will be integrated into a functional and transportable unit not affected by the outdoor conditions and producing minimal emissions. To achieve this, the system will be powered mainly by solar energy and will recycle the water used. Specifically developed devices such as wireless sensors and LED lamps will be used to monitor and enhance the cultivation process, reduce the energy consumption and decrease the overall cost due to their high efficiency, long lifetime and low maintenance.

    The LED grow lights used have a continuous spectrum that has been selected and specifically tailored to the plants’ needs. Nevertheless, seedlings pre-cultivated under LED lights could face UV stress after transplanting to open land as these wavelengths are not included in the light spectrum used in the growth chamber. Moreover, light intensity levels during indoor cultivation are usually much lower compared to the outdoor conditions, which can cause a light shock to the plants. Juvenile plants are less efficient in the utilization of the absorbed light, and therefore, prone to photoinhibition by radiation fluxes that usually do not harm mature plants. Plant protective mechanisms against UV radiation and high PAR (400-700nm) light intensity are partly overlapping. Hence, exposure to UV or high light intensity before transplanting, or introducing a transient phase by using shading cloths during transplantation period could help to reduce this stress.

    The aim was to reduce the transplanting stress of Picea abies and Pinus sylvestris seedlings grown under LED-lamps for the first 5 weeks of cultivation. We investigated how different methods; UV-A pre-treatment or high irradiance during the indoor cultivation or usage of shading cloths for the first week(s) after transplanting outdoors can be used to mitigate light shock stress. Different methods and exposure times showed varying ability in ensuring good seedling growth and survival.

  • 18.
    Hernandez Velasco, Marco
    et al.
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Mattsson, Anders
    Dalarna University, School of Technology and Business Studies, Forest and Wood Technology.
    A silvicultural practice to facilitate forest restoration: a new seedling cultivation technology for regeneration establishment2014In: The International Forestry Review Vol.16 (5), 2014 / [ed] John A. Parrotta, Cynthia F. Moser, Amy J. Scherzer, Nancy E. Koerth and Daryl R. Lederle, The Commonwealth Forestry Association, www.cfa-international.org , 2014, Vol. 16, no 5, p. 129-Conference paper (Other academic)
    Abstract [en]

    Forest restoration has become a primary task, not only to cope with an increasing demand on forest products, but also to fi ghtclimate change and compensate for an accelerated global deforestation. However, many of the current practices used in forestrynurseries to produce forest planting stock have adverse effects on the environment. The main objective of the ZEPHYR project,funded by the European Commission under the Seventh Framework Programme (FP7), is to develop an innovative zero-impacttechnology for the pre-cultivation of forest regeneration materials that is not affected by the outdoor climate. Among the maincomponents to be improved are artifi cial lighting sources used for cultivation. Traditional fl uorescence lamps are to be replacedby LED grow lights with spectra tailored to the seedlings’ needs. The present work investigates biological responses of Piceaabies and Pinus sylvestris to six different light spectra. The pre-cultivation has been done following standard growth protocolsduring 5 weeks with a photoperiod of 16 h at 100 μmol/m2/s. This has been done under controlled closed conditions with a roomtemperature of 20 °C and a relative humidity of 60%. The analyses have shown clear differences among the treatments and theiradapting capacity when transplanted.

  • 19.
    Hernandez Velasco, Marco
    et al.
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Mattsson, Anders
    Dalarna University, School of Technology and Business Studies, Forest and Wood Technology.
    Cultivation of forest regeneration materials under artificial radiant sources—effects of light intensity on energy consumptionand seedling development2014In: The International Forestry Review Vol.16 (5), 2014 / [ed] John A. Parrotta, Cynthia F. Moser, Amy J. Scherzer, Nancy E. Koerth and Daryl R. Lederle, 2014, Vol. 16, no 5, p. 300-300Conference paper (Other academic)
    Abstract [en]

    In times of major environmental challenges and increasing demand for forest products, planted forests have acknowledgedadvantages compared to other land uses. Despite not being able to completely take the place of natural forests, planted ones have,if properly managed, great potential to contribute in addressing these problems. Besides the ecological benefi ts such as carbonsequestration, planted forests can help meet the demand for wood products without further depletion of the natural forest. Forestrestoration, rehabilitation, and reforestation are limited by the capacity for producing forest regeneration materials. Often, asproduction is intensifi ed at forest nurseries, the practices begin to have an adverse impact on the environment and stop being trulysustainable. One of the main issues in nurseries is the energy consumption for grow lights during periods of short daylight.By using high-effi ciency LED grow lamps and adjusting the light intensity, this study aimed to reduce the energy consumptionfrom lighting per seedling without compromising seedling development. The precultivation of Picea abies and Pinus sylvestrisseedlings was done during 5 weeks under controlled conditions at 20 °C and a relative humidity of 60%. The photoperiod was16 hours at an intensity ranging from 50 to 350 μmol/m2/s in intervals of 50 μmol/m2/s intervals.

  • 20.
    Hernandez Velasco, Marco
    et al.
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Mattsson, Anders
    Dalarna University, School of Technology and Business Studies, Forest and Wood Technology.
    Energy efficiency in intensified production of forest regeneration materials – design of a photovoltaic system for sustainably powering an innovative forestry incubator2014In: The International Forestry Review Vol.16 (5), 2014 / [ed] John A. Parrotta, Cynthia F. Moser, Amy J. Scherzer, Nancy E. Koerth and Daryl R. Lederle, 2014, Vol. 16, no 5, p. 393-393Conference paper (Other academic)
    Abstract [en]

    Planted forests can contribute addressing problems of global concern such as climate change mitigation, biodiversity lost and pressure on ecosystems due to high demand of forestry products. However, in order to be able to profit from these benefits sustainably, production rates of forest regeneration materials should be higher than the harvesting rates. Nevertheless, intensive production methods often bring along adverse consequences for the environment. In the frame of the ZEPHYR project, funded by the European Commission under the Seventh Framework Programme (FP7), innovative and cost-friendly technologies for the pre-cultivation are being developed. They will be integrated into a functional and transportable system for a large scale production of seedlings, with zero-impact on the environment and not affected by outdoor conditions. To achieve this, high efficiency devices with low energy consumption will be used and the incubator will be powered by solar energy. This work aims to present the efforts made to reduce the energy loads and optimize the photovoltaic (PV) system. The power system will also be capable of connecting to the electricity grid, using a diesel generator as a back-up, and a battery bank with at least one day of autonomy (up to 7 kWh/day) in central European latitudes.   

  • 21.
    Hernandez Velasco, Marco
    et al.
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Mattsson, Anders
    Dalarna University, School of Technology and Business Studies, Forest and Wood Technology.
    Long night treatment for induction of cold hardiness using artificial lights: effects of photoperiod on seedling storabilityand energy consumption2014In: The International Forestry Review Vol.16 (5), 2014 / [ed] John A. Parrotta, Cynthia F. Moser, Amy J. Scherzer, Nancy E. Koerth and Daryl R. Lederle, 2014, Vol. 16, no 5, p. 379-379Conference paper (Other academic)
    Abstract [en]

    Human-assisted forest regeneration in Nordic climates is considerably limited by the harsh outdoor conditions. There is onlya small open window of time during the summer when the weather is favorable for transplantation and establishment ofpre-cultivated seedlings in open land. Greenhouses and modern growth chambers help to cope with this limitation by allowingyear-round seedling cultivation. Nonetheless, production levels are constrained to the cold storage capacity during the nontransplantingseason. This storage is in turn dependent on the ability of the conifer to adapt to freezing temperatures and withstand theoverall stress associated with cold hardening. Long night treatments can induce dormancy with cessation of growth and terminalbuds initiation, leading to a better cold resistance. When growing forest regeneration materials under artifi cial lights, the lengthsof the long night treatment and the photoperiod will have a signifi cant impact not only on the biological response of the seedlingsbut also on the energy consumption, and thus on the CO2 emissions. The aim of this work was to explore different long nighttreatment regimes for induction of cold hardiness in Picea abies and Pinus sylvestris seedlings using artifi cial lights. This wasdone with the purpose of studying the relationship between the energy consumption and the biological responses.

  • 22.
    Hernandez Velasco, Marco
    et al.
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Mattsson, Anders
    Dalarna University, School of Technology and Business Studies, Forest and Wood Technology.
    Nuevas tecnologías para el pre-cultivo de plantas forestales - diseño de una incubadora sustentable para minimizar el impacto ambiental2014In: VI Congreso Forestal Latinoamericano: Latinoamérica unida en armonia por la sustentabilidad de los recursos forestales, 2014Conference paper (Other academic)
    Abstract [es]

    Los bosques plantados pueden contribuir a combatir problemas globales como el cambio climático, la erosión del suelo y la presión en los ecosistemas debido a la alta demanda de productos forestales. Para que este beneficio sea sustentable, la producción del material para la regeneración forestal tiene que ser mayor a la velocidad en que se tala. Las técnicas intensivas en los viveros forestales puede traer efectos adversos al ambiente como el uso de fertilizantes, pesticidas y alto consumo energético de los invernaderos. 

    Financiado por Séptimo Programa de Investigación y Desarrollo de la Unión Europea, el proyecto ZEPHYR está enfocado a desarrollar nuevas tecnologías para el pre-cultivo de plantas forestales de una manera sustentable y económicamente viable. Estas innovaciones estarán integradas en una incubadora transportable y totalmente funcional para la producción a gran escala. El cuarto de crecimiento será independiente de las condiciones exteriores y tendrá un mínimo impacto ambiental. Para lograr esto se usaran aparatos de alta eficiencia y bajo consumo energético como lámparas LED y todo funcionará con un sistema solar fotovoltaico.

  • 23.
    Hernandez Velasco, Marco
    et al.
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Mattsson, Anders
    Dalarna University, School of Technology and Business Studies, Forest and Wood Technology.
    Outdoor performance of forest seedlings pre-cultivated under artificial lights: effects of the light spectra used for pre-cultivation on the future establishment and development2015In: Rainforest challenges: Book of abstracts / [ed] Vladan Ivetić and Tatjana Ćirković‐Mitrović , 2015, p. 20-20Conference paper (Other academic)
    Abstract [en]

    Forest nurseries are essential for producing good quality seedlings, thus being a key element in the reforestation process. With increasing climate change awareness, nursery managers are looking for new tools that can help reduce the effects of their operations on the environment. The ZEPHYR project, funded by the European Commission under the Seventh Framework Programme (FP7), has the objective of finding new alternatives for nurseries by developing innovative zero-impact technologies for forest plant production. Due to their direct relationship to the energy consumption of the nurseries, one of the main elements addressed are the grow lights used for the pre-cultivation. New LED luminaires with a light spectrum tailored to the seedlings’ needs are being studied and compared against the traditional fluorescent lamps. Seedlings of Picea abies and Pinus sylvestris were grown under five different light spectra (one fluorescent and 4 LED) during 5 weeks with a photoperiod of 16 hours at 100 μmol∙m-2∙s-1 and 60% humidity. In order to evaluate if these seedlings were able cope with real field stress conditions, a forest field trial was also designed. The terrain chosen was a typical planting site in mid-Sweden after clear-cutting. Two vegetation periods after the outplanting, the seedlings that were pre-cultivated under the LED lamps have performed at least as well as those that were grown under fluorescent lights. These results show that there is a good  potential for lightning substitution in forestry nurseries.

  • 24.
    Hernandez Velasco, Marco
    et al.
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Mattsson, Anders
    Dalarna University, School of Technology and Business Studies, Forest and Wood Technology.
    Swedish experiences and visions on the production of containerized seedlings2016In: / [ed] Palle Madsen, 2016Conference paper (Other academic)
  • 25.
    Hernandez Velasco, Marco
    et al.
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Pérez-Mora, Nicolás
    University of Balearic Islands and Sampol Ingenieria y Obras.
    Marras, Tatiana
    Universita degli Studi della Tuscia.
    Using Hybrid Solar Photovoltaic + Combined Heat and Power Systems (PV+CHP) to Enable Industrial Scale Indoor Plant Cultivation: a Feasibility Study2016Conference paper (Other academic)
    Abstract [en]

    A rapid population growth linked to intensive agriculture has originated several problems such as soil degradation, groundwater depletion, forestland transformation, and eutrophication of aquatic systems. Vertical farming offers an alternative for producing plants indoors in a resources and space efficient manner, reducing leakage of chemicals, optimizing water and land use, and allowing year-round cultivation. Controlled environment agriculture (CEA) also enables urban residents to access locally grown plants that would have otherwise been imported from far away, reducing transport and storage emissions. This comes with a caveat: the energy loads increase to provide artificial illumination and keep an optimal climate. To address this issue, the present work studies the feasibility of using a hybrid photovoltaics and combined heat and power system (PV+CHP) to satisfy the energy demands of an industrial-sized growth room. For this, different European locations and climates have been considered as well as various growth protocols.

  • 26.
    Hernandez Velasco, Marco
    et al.
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    R Pamidi, Sreenivaasa
    Exergy Ltd..
    The Zephyr concept and the energetic autonomy2014In: CAFFEINA 2014: Il Futuro e le Radici - The Future and the Roots, 2014Conference paper (Other academic)
    Abstract [en]

    Currently, forest ecosystems are facing many sustainability problems due to drastic climate changes and extreme exploitation of their resources. Planted forests can contribute to more sustainable practices and help addressing some of these issues. In order to be able to profit from these benefits sustainably, production rates of forest regeneration materials should be higher than the harvesting rates. Nevertheless, intensive production methods often bring along adverse consequences for the environment.

    At the moment, there exist several options such as greenhouses or plant growth chambers that allow producing forest materials more rapidly. Unfortunately these systems consume considerable high amounts of energy for lighting, acclimatization and irrigation having a negative impact on the environment.

    The Zephyr project aims to introduce an innovative technology built on pre-cultivation of forest regeneration materials in a zero-impact and cost-friendly production unit. The project will integrate several technologies into a functional and transportable system for large scale production of pre-cultivated forest regeneration materials adapted to transplanting and further growth at forest nurseries.

    A transportable and closed incubator independent from the outdoor climate provides a better control on the seedlings production. The plants can be produced directly at the place where they are needed avoiding further transportation to the reforestation/afforestation zone. The closed-climate allows seedlings pre-cultivation in places where it would not be possible otherwise (e.g. near deserts). Additionally, it extends the production time throughout the whole year even during the winter. Moreover, it will allow a certified and standardized production of reforestation materials, with a noticeable increasing of the efficiency of the reforestation operations.

    Specially developed LED growth lamps and wireless sensors will be used to reduce energy consumption and monitor the cultivation process. The main part of the energy will be provided by solar PV-panels, depending from the geographic and climatic area the power system should be able to provide at least one day of autonomy (in central Europe). The energy savings will result in a reduction of greenhouse gas emissions; moreover, since the LED lamps do not produce additional warming, there will be further energy saving through the reduction of air conditioning costs.

    The PV system is designed based on the load specifications of the different subsystems involved for advanced state-of-art pre-cultivation of forest seedlings. It will be further evaluated based on the changes in the load profiles as the growth protocols for different species are defined.  The main objectives are to maximize the power/energy flow delivered to the load and to investigate feasible options for an external backup power source whilst considering options to reduce the overall load of the system.

  • 27. Hogberg, Karl-Anders
    et al.
    Persson, Bengt
    Dalarna University, School of Technology and Business Studies, Forest and Wood Technology.
    Hallingback, Henrik R.
    Jansson, Gunnar
    Relationships between early assessments of stem and branch properties and sawn timber traits in a Pinus sylvestris progeny trial2010In: Scandinavian Journal of Forest Research, ISSN 0282-7581, E-ISSN 1651-1891, Vol. 25, no 5, p. 421-431Article in journal (Refereed)
    Abstract [en]

    A sample of 162 trees was harvested from a 36-year-old Scots pine (Pinus sylvestris L.) progeny trial to evaluate correlations between early measurements of branch diameter, and other stem and branch traits, with sawn timber traits, and hence their potential utility for predicting wood quality. The sample trees were assigned to three genetic groups of small, medium and large branch diameter, based on parental breeding values. Bottom logs were cut and sawn, and several important traits for the visual quality of the boards were assessed. Phenotypic correlations were then estimated between these traits and measurements of the height, diameter, branch diameter, branch angle, stem crookedness, number of branches and grain angle under bark of the corresponding trees when they were 16 and 36 years old. The diameter of the coarsest knot in the board was correlated with the branch diameter at the age of 16 years (0.50), and there were significant differences in this trait among the genetic branch diameter groups. In addition, the board twist was correlated with the grain angle under bark at the age of 36 years (0.54). Thus, the field assessments of branch diameter and grain angle under bark show relevance for the visual quality of centrally sawn small timber.

  • 28.
    Jonsdottir, Rakel J.
    et al.
    Norðurlandsskógar, Krókeyri, IS-600, Akureyri, Iceland.
    Sigurdsson, Bjarni D.
    Faculty of Environmental Sciences, Agricultural University of Iceland, Hvanneyri, IS-311, Borgarnes, Iceland.
    Lindström, Anders
    Dalarna University, School of Technology and Business Studies, Forest and Wood Technology. School for Forest Management, Swedish University of Agricultural Sciences, Box 43, 739 21 Skinnskatteberg, Sweden.
    Effects of nutrient loading and fertilization at planting on growth and nutrient status of Lutz spruce (Picea x lutzii) seedlings during the first growing season in Iceland2013In: Scandinavian Journal of Forest Research, ISSN 0282-7581, E-ISSN 1651-1891, Vol. 28, no 7, p. 631-641Article in journal (Refereed)
    Abstract [en]

    The low availability of nitrogen (N) is believed to be one of the major limiting factors of forest regeneration inIceland and frequently under Boreal conditions. Lutz spruce (Picea x lutzii Littl.) seedlings were nutrient loadedusing four fertilization regimes in the end of nursery rotation in autumn 2008 and planted in the following spring,with or without a single dose of fertilizer, on two treeless sites in N-Iceland with contrasting soil fertility.Measurements were made after one growing season. The highest loading level without additional field fertilizationincreased new needle mass by 122% and 152%, for the poor and more fertile site, respectively. The highest loadinglevel with field fertilization increased new needle mass equally, by 188% and 189%, for the poor and more fertilesite, respectively. Retranslocation of N, from old needles to current needles, increased with more loading.However, it was clear that nutrient loading could not replace field fertilization, as the seedlings generally showedan additive response to field fertilization and nutrient loading; doing both always gave the best results in seedlingperformance. As the study only covers field establishment during the first year, the long-term effect of nutrientloading of Lutz spruce cannot be predicted. However, it was concluded that loading might provide an additionalinput for faster plantation establishment during the first growing season after planting.

  • 29. Joosen, R.V.L.
    et al.
    Lammers, M.
    Balk, P.
    Brönnum, P.
    Konings, M.C.J.M.
    Perks, M.
    Stattin, Eva
    Dalarna University, School of Technology and Business Studies, Wood Technology.
    van Wordragen, M.F.
    Geest, L.H.M.
    Correlating gene expression to physiological parameters and environmental conditions during cold acclimation of Pinus sylvestris, identification of molecular markers using cDNA microarrays2006In: Tree Physiology, ISSN 0829-318X, E-ISSN 1758-4469, Vol. 26, no 10, p. 1297-1313Article in journal (Refereed)
    Abstract [en]

    Scots pine (Pinus sylvestris L.) seedlings were grown under different conditions (three field locations, two seasons and two climate room regimes), and then analyzed for freezing tolerance of shoots and roots and for transcript abundance in apical buds based on a cDNA microarray containing about 1500 expressed sequence tags (ESTs) from buds of cold-treated Scots pine seedlings. In a climate room providing long daily photoperiods and high temperatures, seedlings did not develop freezing tolerance, whereas seedlings in a climate room set to provide declining temperatures and day lengths developed moderate freezing tolerance. Control seedlings grown outside under field conditions developed full freezing tolerance. Differences in physiological behavior of the different seedling groups, combined with molecular analysis, allowed identification of a large group of genes, expression of which changed during the development of freezing tolerance. Transcript abundance of several of these genes was highly correlated with freezing tolerance in seedlings differing in provenance, field location or age, making them excellent candidate marker genes for molecular tests for freezing tolerance.

  • 30. Kännaste, Astrid
    et al.
    Zhao, Tao
    Lindström, Anders
    Dalarna University, School of Technology and Business Studies, Forest and Wood Technology.
    Stattin, Eva
    Dalarna University, School of Technology and Business Studies, Forest and Wood Technology.
    Långström, Bo
    Borg-Karlson, Anna-Karin
    Odors of Norway spruce (Picea abies L.) seedlings: differences due to age and chemotype2013In: Trees, ISSN 0931-1890, E-ISSN 1432-2285, Vol. 27, no 1, p. 149-159Article in journal (Refereed)
    Abstract [en]

    Small conifer seedlings (mini-seedlings) are less damaged by the large pine weevil Hylobius abietis (L.) (Coleoptera: Curculionidae) compared to conventional seedlings. Chemical difference between the seedling types is one possible explanation for this phenomenon. In the present paper, the emissions of volatile organic compounds (VOC) of 7- to 43-week-old Norway spruce [Picea abies (L.) Karst.] seedlings were analyzed. Collection and identification of the volatiles was made by solid phase micro-extraction and gas chromatography mass spectrometry (SPME–GC–MS). The enantiomers of α-pinene and limonene were separated in a two-dimensional GC (2D-GC). Most of the seedlings represented either a limonene- or a bornyl acetate-chemotype. Only minor changes in the volatile composition of the two types of seedlings were found during the first year. Age-related changes, however, were found in the volatiles released by wounded phloem where green leaf volatiles (GLVs) and borneol were the dominated VOC for young seedling. The attractive compound for the pine weevil, α-pinene, was first detected in the phloem emissions of 18- to 22-week-old seedlings. Different storage conditions of the seedlings during the winter/early spring-phase influenced the volatile composition in the phloem. High amount of GLVs was characteristic for the 43-week-old seedlings stored in naturally changing outdoor temperature, but not present in the seedlings winter-stored at a constant temperature of −4 °C. The possible role of these observed differences in odor emissions between seedlings of different age and physiological status for the feeding preferences of the large pine weevil is discussed.

  • 31.
    Lindström, Anders
    et al.
    Dalarna University, School of Technology and Business Studies, Forest and Wood Technology.
    Hellqvist, Claes
    Dalarna University, School of Technology and Business Studies, Forest and Wood Technology. Sveriges Lantbruksuniversitet.
    Etablering, tillväxt och skador för plantor odlade i såddrör (Tubesprout™) - resultat efter två säsonger i fält2013Report (Other academic)
    Abstract [sv]

    Försöket visade på mycket god överlevnad för plantor odlade i såddrören, Tubesprout™. Efter två år var överlevnaden för dessa 91 % för tall och 79 % för gran. För miniplantorna odlade i Jiffy varierade överlevnaden efter två år mellan 84 (tall) och 64 % (gran). Lägst överlevnad efter både det första och andra året hade de större referensplantorna. Av dessa levde 67 % av tallplantorna och endast 45 % av granplantorna. Bidragande till den goda överlevelsen hos Tubesprout™-odlade plantor var få snytbaggeskador och nästan inga skador av torka. Det andra miniplantsystemet, Jiffy 18, klarade snytbaggen nästan lika bra som Tubesprout™, men drabbades istället av stora avgångar beroende på torka. Hylsan tycks förhindra uttorkning av plantan som annars är ett stort problem vid plantering på torra marker av små plantor. För de äldre täckrotsodlade referensplantorna var den mesta plantdöden orsakad av kraftiga snytbaggeskador. Granen var värst drabbad med drygt 50 % snytbaggedödade plantor efter två år, medan den plantavgång hos tall som var orsakad av snytbagge var 26 %. Några plantor som stod i Tubesprout™ på försöksytan blev dock uppryckta, sannolikt av kråkfåglar.

  • 32.
    Lindström, Anders
    et al.
    Dalarna University, School of Technology and Business Studies, Forest and Wood Technology. School for Forest Management, Swedish University of Agricultural Sciences, Skinnskatteberg.
    Stattin, Eva
    Dalarna University, School of Technology and Business Studies, Forest and Wood Technology.
    Gräns, Daniel
    Dalarna University, School of Technology and Business Studies, Forest and Wood Technology. School for Forest Management, Swedish University of Agricultural Sciences, Skinnskatteberg.
    Wallin, Elisabeth
    Dalarna University, School of Technology and Business Studies, Energy and Environmental Technology. School for Forest Management, Swedish University of Agricultural Sciences, Skinnskatteberg.
    Storability measures of Norway spruce and Scots pine seedlings and assessment of post storage vitality by measuring shoot electrolyte leakage2014In: Scandinavian Journal of Forest Research, ISSN 0282-7581, E-ISSN 1651-1891, Vol. 29, no 8, p. 717-724Article in journal (Refereed)
    Abstract [en]

    As indoor frozen storage is increasing in forest tree nurseries it is important to have accurate methods for assessing seedling storability in autumn and methods to determine post-storage vitality. Storability of spruce (Picea abies (L.) Karst.) and pine (Pinus sylvestris L.) seedlings can be based on determination of dry matter content (DMC) of seedling shoots or by freezing shoots at -25 degrees C and thereafter measure electrolyte leakage (SELdiff-25). To compare these two methods we stored 1-year-old spruce and pine seedlings at different occasions during the autumn. To test if leakage of electrolytes from shoots (SEL) could indicate deteriorated vitality, we measured SEL at the end of storage. After storage seedling viability was determined in a three-week growth test, measuring shoot and root growth capacity (RGC). Determination of freezing tolerance (SELdiff-25) before storage had a better ability to predict the outcome of storage compared to the DMC test. Measuring SEL at the end of the frozen storage period accurately indicated seedling vitality. Seedlings with SEL of 0-5% had a high survival rate whereas SEL over 10% indicated low survival and growth capacity after storage. The SEL method has a potential to become a screening test for identifying batches of seedlings that have been damaged during storage in the nursery.

  • 33. Malmqvist, C.
    et al.
    Wallin, Elisabeth
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Lindström, Anders
    Dalarna University, School of Technology and Business Studies, Forest and Wood Technology.
    Säll, H.
    Differences in bud burst timing and bud freezing tolerance among interior and coastal seed sources of Douglas fir2017In: Trees, ISSN 0931-1890, E-ISSN 1432-2285, Vol. 31, no 6, p. 1987-1998Article in journal (Refereed)
    Abstract [en]

    The need for species that will grow well through ongoing climate change has increased the interest in Douglas fir [Pseudotsuga menziesii (Mirb.) Franco] in Sweden. One of the most common problems seen in plantations of Douglas fir seedlings is damage caused by late spring frost, known to be highly correlated with the timing of bud burst. The objective of this study was to investigate spring-related bud development under Nordic conditions of seven Douglas fir provenances and to compare data with a local provenance of Norway spruce (Picea abies (L.) Karst). Results from a field trial and a greenhouse-based study were compared. The interior Douglas fir provenances exhibited an earlier bud burst than coastal provenances, both in the greenhouse and in the field trial. When comparing differences within the groups of interior and coastal Douglas fir provenances, no differences could be found. The local Norway spruce, only grown in the greenhouse, showed an intermediate bud development profile similar to the interior Douglas fir provenance Three Valley. We therefore suggest that Three Valley could be planted at the same locations as the investigated local provenance of Norway spruce in mid-Sweden. To avoid spring frost damage the Douglas fir seedlings need to be frozen stored and planted late in spring. Planting under shelterwood can also help protect the seedlings from spring frost damages. As similar results for bud development patterns of Douglas fir and Norway spruce provenances were obtained from the greenhouse and field trials, greenhouse tests could facilitate selection of provenances.

  • 34.
    Malmqvist, Cecilia
    et al.
    Dept of Forestry and Wood technology, Linneus University, Växjö, Sweden.
    Wallertz, Kristina
    Asa Forest Research Station, Swedish University of Agricultural Sciences, Lammhult Sweden.
    Lindström, Anders
    Dalarna University, School of Technology and Business Studies, Forest and Wood Technology.
    Storability and freezing tolerance of Douglas fir and Norway spruce seedlings grown in mid-Sweden2017In: Scandinavian Journal of Forest Research, ISSN 0282-7581, E-ISSN 1651-1891, Vol. 32, no 1, p. 30-38Article in journal (Refereed)
    Abstract [en]

    Climate change provides new challenges to Nordic forestry. Use of non-native species, such as Douglas fir, can be a means of mitigating the effects of climate change and meeting the growing demand for biomass. When Douglas fir is grown in Sweden, it is several degrees of latitude north of its normal range, which can affect timing of growth cessation, hardening of seedlings, and seedling storability. The objective of this study was to investigate tolerance to freezing and sub-zero storability of seven Douglas fir provenances and make comparisons with the native Norway spruce. Freezing tolerance and storability were evaluated by measuring the electrolytic leakage of shoots and roots after freezing, complemented with a three-week cultivation test after storage. All provenances of Douglas fir used in this study were able to tolerate frozen storage at −4°C for about four months. Norway spruce and the interior Douglas fir provenance, Three Valley, could be stored earlier in the autumn than the southern coastal Douglas fir provenances. Consequently, it should be possible to store Douglas fir seedlings with the same routines as for Norway spruce.

  • 35.
    Mattsson, Anders
    Dalarna University, School of Technology and Business Studies, Forest and Wood Technology.
    Reforestation challenges in Scandinavia2016In: Reforesta, ISSN 2466-4367, no 1, p. 67-85Article in journal (Refereed)
    Abstract [en]

    In the keynote, major reforestation challenges in Scandinavia will be highlighted. The following countries make up Scandinavia: Iceland, Norway, Sweden, Finland and Denmark. For Iceland, with only a forest cover of 2%, a major reforestation challenge is the deforestation and overgrazing in combination with land degradation and extensive soil erosion. The challenges include the conflicts with livestock farmers. For centuries the commons were used for sheep and horse grazing. However, more and more of farmer grazing land have been fenced up, allowing the regeneration of birch and plantations of other species to increase. With a forest cover of 37% and 69% respectively, for decades a major reforestation challenge in Norway and Sweden has been the risk of seedling damages from the pine weevil. Unprotected seedlings can have a survival rate of less than 25% after being planted. Pine weevils feed on the bark of planted young seedlings at regeneration sites. If the seedling is girdled, it will not survive. In Sweden, and soon in Norway, pesticides have been forbidden. In the keynote, new methods and technology will be presented based on non-chemical protection. In Finland, with a forest cover of 75%, a major reforestation challenge is linked to the forest structure. The structure of Finnish forestry includes many private forests in combination with small regeneration sites. This implies a situation where logistics and methods for lifting and field storage provide a major challenge in order to preserve seedling quality until the planting date. Due to this situation, new logistic systems and technologies are being developed in Finland, including new seedling cultivation programs (including cultivation under Light Emitting Diodes (LEDs)) to match the access of fresh planting stock to different planting dates. In Denmark, with a forest cover of 13%, a major reforestation challenge is the possibility of future plantations based on a wide range of relevant species. For this to become a realistic option, new methods and technology have to be developed in reforestation activities that support this possibility. These methods and technology should make it possible to not be limited to certain species due to problems and restrictions during field establishment. This due to the prospect of establishing stable, healthy, and productive stands of various forest species that can be adapted to future climate change.

  • 36.
    Mattsson, Anders
    et al.
    Dalarna University, School of Technology and Business Studies, Forest and Wood Technology.
    Hernandez Velasco, Marco
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Rusu, Cristina
    Acreo Swedish ICT AB.
    Pietrzak, Malgorzata
    Azorina S.A.
    Ferreira, Raquel
    Azorina S.A.
    Radoglou, Kalliopi
    Democritus University of Thrace.
    Smirnakou, Sonia
    Democritus University of Thrace.
    Bantis, Filippos
    Democritus University of Thrace.
    Fulgaro, Nicoletta
    Università degli Studi dell'Insubria.
    Kotilainen, Titta
    Valoya OY.
    ZEPHYR Project – Deliverable D7.6: Articles and peer-reviewed papers2015Report (Other (popular science, discussion, etc.))
  • 37.
    Mattsson, Anders
    et al.
    Dalarna University, School of Technology and Business Studies, Forest and Wood Technology.
    Radoglou, K
    Kostopoulou, P
    Bellarosa, R
    Simeone, M.C.
    Shirone, B
    Use of innovative technology for the production of high-quality forest regeneration materials2010In: Scandinavian Journal of Forest Research, ISSN 0282-7581, E-ISSN 1651-1891, Vol. 25, no Suppl 8, p. 3-9Article in journal (Refereed)
    Abstract [en]

    The aim of this paper is to introduce the innovative technology created within the framework of PRE-FOREST project, funded by the European Commission under the CRAFT 6th Framework Research Programme. PRE-FOREST was an innovative research project in the field of forest planting stock material, enhancing co-operation between research foundations and small and medium-sized enterprises. Among the project's objectives were the introduction of a new technology based on precultivation (in mini-plugs) of forest regeneration material in a cost-efficient and environmental friendly production unit, not affected by outdoor climate; the development of a new, adapted to mini-plugs, grading technology and replug robot; the integration of these technologies into a functional prototype unit capable of large-scale forest regeneration material production; and the introduction of this production system at strategic locations in Europe. The system has been developed for year-round production and function in the same way, independently of climatic variations in different parts of Europe. To obtain these objectives the study focused on the interaction among production technology, mini-plug container design and rooting media, to develop cultivation protocols for forest reproductive materials of special economic and ecological importance for each participating country. One of the main benefits of the new technology was the environmentally friendly production of a large number of seedlings per square metre, leading to a cost-efficient result.

  • 38.
    Pamidi, Sreenivaasa R
    et al.
    Exergy Ltd..
    Hernandez Velasco, Marco
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Reducing the impact of forest plant production - Design of a stand-alone PV-hybrid system for powering an innovative forestry incubator2014In: 29th European Photovoltaic Solar Energy Conference and Exhibition Proceedings, 2014, p. 3811-3814Conference paper (Other academic)
    Abstract [en]

    Nowadays, the high demand of forestry products imposes a high pressure on the ecosystems and can derive in biodiversity lost and other ecological problems. Planted forests can contribute to more sustainable practices and help addressing other problems of global concern such as climate change, erosion and desertification. Large scale production of seedling is required to offset the high harvesting rates; however these intensive methods often have a negative impact on the environment. Funded by the European Commission under the Seventh Framework Programme (FP7), the ZEPHYR project consortium is developing innovative and cost-friendly technologies for the pre-cultivation of forestry species. These will be integrated into a functional and transportable system for pre-cultivation of seedlings, with zeroimpact on the environment and not affected by outdoor conditions. To achieve this, the incubator will be powered mainly by solar energy. This work aims to present the efforts made to design and optimize the solar photovoltaic (PV) system which will be mounted on the roof of the unit. Especially developed devices such as LED growth lamps and wireless sensors will be used to reduce energy consumption and monitor the cultivation process. A load profile study was conducted and the growth protocols were adapted to perform most of the tasks during daytime to use the energy from the PV panels directly. A battery bank will be designed to provide at least one day of autonomy in central European latitudes. Moreover, the power system will also be capable of connecting to the electricity grid or use a diesel generator as a backup.

  • 39. Pettersson, Marie
    et al.
    Kännaste, Astrid
    Lindström, Anders
    Dalarna University, School of Technology and Business Studies, Forest and Wood Technology.
    Hellqvist, Claes
    Stattin, Eva
    Dalarna University, School of Technology and Business Studies, Forest and Wood Technology.
    Långström, Bo
    Borg-Karlsson, Anna-Karin
    Mini-seedlings of Picea abies are less attacked by Hylobius abietis than conventional ones: is plant chemistry the explanation?2008In: Scandinavian Journal of Forest Research, ISSN 0282-7581, E-ISSN 1651-1891, Vol. 23, no 4, p. 299-306Article in journal (Refereed)
    Abstract [en]

    The pine weevil, Hylobius abietis (L.), is a major pest in conifer reforestation areas in the Palaearctic region. Size and chemistry of the seedlings may explain the damage rates in plantations. The performance of 10-week containerized seedlings (mini-seedlings) was compared with 1-year-old conventional seedlings of Norway spruce, Picea abies (L.), in a field experiment in central Sweden. After 2 years the weevil damage was lower for the mini-seedlings than for the conventional seedlings (3.5 vs 55%). After 3 years, the overall survival was 82 and 75%, respectively. Weevil damage was the main cause of mortality for conventional seedlings, whereas mini-seedlings mainly died from drought. Volatiles of the two seedling types were compared by solid-phase microextraction-gas chromatography-mass spectrometry (SPME-GC-MS). Unwounded mini-seedlings and conventional seedlings differed in their compositions of monoterpenes and sesquiterpenes. Mini-seedlings mainly emitted limonene, known to be repellent to the pine weevil. When wounded, green leaf volatiles were released by mini-seedlings while the pine weevil attractant -pinene was released by conventional seedlings. Volatiles may partly explain the mini-seedlings' resistance against weevil attack. Further studies are needed to clarify how long this mini-seedling effect remains.

  • 40.
    Radoglou, Kalliopi
    et al.
    Democritus University of Thrace.
    Sismanis, Nikos
    Democritus University of Thrace.
    Smirnakou, Sonia
    Democritus University of Thrace.
    Mattsson, Anders
    Dalarna University, School of Technology and Business Studies, Forest and Wood Technology.
    Hernandez Velasco, Marco
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Schirone, Bartolomeo
    Universita degli Studi della Tuscia.
    Marras, Tatiana
    Universita degli Studi della Tuscia.
    Vessella, Federico
    Universita degli Studi della Tuscia.
    Chiatante, Donato
    Università degli Studi dell'Insubria.
    Terzaghi, Mattia
    Università degli Studi dell'Insubria.
    Fulgaro, Nicoletta
    Università degli Studi dell'Insubria.
    Montagnoli, Antonio
    Università degli Studi dell'Insubria.
    ZEPHYR Project – Deliverable D3.2: Intermediate report on growth tests2014Report (Other (popular science, discussion, etc.))
  • 41. Skarin, A.
    et al.
    Alam, Moudud
    Dalarna University, School of Technology and Business Studies, Statistics.
    Reindeer habitat use in relation to two small wind farms, during preconstruction, construction, and operation2017In: Ecology and Evolution, ISSN 2045-7758, E-ISSN 2045-7758, Vol. 7, no 11, p. 3870-3882Article in journal (Refereed)
    Abstract [en]

    Worldwide there is a rush toward wind power development and its associated infrastructure. In Fennoscandia, large-scale wind farms comprising several hundred windmills are currently built in important grazing ranges used for Sámi reindeer husbandry. In this study, reindeer habitat use was assessed using reindeer fecal pellet group counts in relation to two relatively small wind farms, with 8 and 10 turbines, respectively. In 2009, 1,315 15-m2 plots were established and pellet groups were counted and cleaned from the plots. This was repeated once a year in May, during preconstruction, construction, and operation of the wind farms, covering 6 years (2009-2014) of reindeer habitat use in the area. We modeled the presence/absence of any pellets in a plot at both the local (wind farm site) and regional (reindeer calving to autumn range) scale with a hierarchical logistic regression, where spatial correlation was accounted for via random effects, using vegetation type, and the interaction between distance to wind turbine and time period as predictor variables. Our results revealed an absolute reduction in pellet groups by 66% and 86% around each wind farm, respectively, at local scale and by 61% at regional scale during the operation phase compared to the preconstruction phase. At the regional, scale habitat use declined close to the turbines in the same comparison. However, at the local scale, we observed increased habitat use close to the wind turbines at one of the wind farms during the operation phase. This may be explained by continued use of an important migration route close to the wind farm. The reduced use at the regional scale nevertheless suggests that there may be an overall avoidance of both wind farms during operation, but further studies of reindeer movement and behavior are needed to gain a better understanding of the mechanisms behind this suggested avoidance.

  • 42.
    Skarin, Anna
    et al.
    Swedish Univ Agr Sci, Dept Anim Nutr & Management, Uppsala.
    Nellemann, Christian
    GRID Arendal, United Nations Environm Programme, Lillehammer, Norway..
    Rönnegård, Lars
    Dalarna University, School of Technology and Business Studies, Statistics.
    Sandstrom, Per
    Swedish Univ Agr Sci, Dept Forest Resource Management, Umea, Sweden.
    Lundqvist, Henrik
    Swedish Univ Agr Sci, Dept Anim Nutr & Management, Uppsala, Sweden.
    Wind farm construction impacts reindeer migration and movement corridors2015In: Landscape Ecology, ISSN 0921-2973, E-ISSN 1572-9761, Vol. 30, no 8, p. 1527-1540Article in journal (Refereed)
    Abstract [en]

    Over the last decade, we have seen a massive increase in the construction of wind farms in northern Fennoscandia. Wind farms comprising hundreds of wind turbines are being built, with little knowledge of the possible cumulative adverse effects on the habitat use and migration of semi-domesticated free-ranging reindeer. We assessed how reindeer responded to wind farm construction in an already fragmented landscape, with specific reference to the effects on use of movement corridors and reindeer habitat selection. We used GPS-data from reindeer during calving and post-calving in the MalAyen reindeer herding community in Sweden. We analysed data from the pre-development years compared to the construction years of two relatively small wind farms. During construction of the wind farms, use of original migration routes and movement corridors within 2 km of development declined by 76 %. This decline in use corresponded to an increase in activity of the reindeer measured by increased step lengths within 0-5 km. The step length was highest nearest the development and declining with distance, as animals moved towards migration corridors and turned around or were observed in holding patterns while not crossing. During construction, reindeer avoided the wind farms at both regional and landscape scale of selection. The combined construction activities associated with even a few wind turbines combined with power lines and roads in or close to central movement corridors caused a reduction in the use of such corridors and grazing habitat and increased the fragmentation of the reindeer calving ranges.

  • 43.
    Skarin, Anna
    et al.
    Sveriges lantbruksuniversitet.
    Sandström, Per
    Sveriges lantbruksuniversitet.
    Alam, Moudud
    Dalarna University, School of Technology and Business Studies, Statistics.
    Buhot, Yann
    Sveriges lantbruksuniversitet.
    Nellemann, Christian
    Rhipto-Norwegian Center for Global Analyses.
    Renar och vindkraft II: Vindkraft i drift och effekter på renar och renskötsel2016Report (Other academic)
    Abstract [en]

    A surge in wind power development and associated road and powerline infrastructure is currently taking place worldwide. In Sweden and Fennoscandia, plans of large-scale wind power mill farms counting several hunderd windmills and their associated infrastructure of roads and powerlines are being implemented. In this report we describe how wind farms not only during construction, but also during operational phases impact reindeer and reindeer husbandry.

    Reindeer behaviour in relation to wind farms were studied in three different study areas in Västerbotten County in northern Sweden. In the Malå reindeer herding community the effects of Storliden and Jokkmokkliden wind farms were assessed during the calving and summer grazing period. In Vilhelmina Norra reindeer herding community, use of the winter grazing range around Stor-Rotliden wind farm was studied.

    Finally, the use of the Lögdeålandets winter grazing range by reindeer from the Byrkije reindeer herding community from Norway was assessed in relation to the Gabrielbergets wind farm. Reindeer habitat use was assessed through reindeer fecal pellet-group counts and by the use of GPS-collars. Data were before and during the construction phase and during the operational phase. We estimated reindeer habitat selection by developing resource selection function (RSF) models for each area in relation to the wind farm areas before, during and after construction. In addition, reindeer use was assessed around Gabrielsberget when 1) the wind farm was turned off for 40 days; 2) during operation when the reindeer were supplementary fed, and 3) during operation without supplementary feeding. Finally, the perception, experiences and views of reindeer herders were assessed through qualitative interviews.

    Our results showed that the reindeer in both calving and winter grazing areas were negatively affected by the wind farm developments. The reindeer avoided grazing in areas where they could see and/or hear the wind turbines and preferred to use areas where the wind turbines were topographically sheltered. In Malå, the reindeer increased the use by 60% of areas topographically sheltered away from the operating wind farms compared to before construction. In winter at Gabrielsberget wind farm, with no supplementary feeding, reindeer largely avoided a 3 km zone.

    When the reindeer were fed inside the wind farm and intensively perimeter herded to stay close to the wind farm, the reindeer still increased their use of areas locally where the wind turbines were sheltered by the topography with 13 %, compared to when they were not fed nor intensively herded. In the calving area in Malå, the use decreased with 16-20 % within 5 km from the wind farm. Moreover, the reindeer significantly increased their movement rate by 18 % within 4 km from the wind farm area during operation phase, compared to before the wind farms were developed.

    Reindeer actively avoid or reduce use of areas within 3 km from wind power farms both during construction and operational phases. Reindeer are more active or vigilant when close to wind power farms. Finally, reindeer tend to – but at more modest extent – to select more sheltered areas close to windmills if forced through supplementary feeding and herding.

    During winter, wind farms situated in upland terrain may reduce the availability and access to reindeer of important higher-altitude winter grazing areas. This may have particular adverse effects and reduce the resilience of reindeer husbandry against extreme weather such as icing by restraining range accessibility. As extreme weather events are expected to be more frequent with climate change, also the ability of reindeer husbandry to adapt becomes reduced with continuing piecemeal infrastructure development.

    The results from our projects have shown that wind farm developments have considerable impacts on reindeer and reindeer husbandry both during the calving season and during the winter season. The impacts for reindeer husbandry may be expected to be most severe in the winter grazing areas, where it often is difficult to find alternative grazing areas. A direct effect of a wind farm in the middle of the winter grazing area, such as Gabrielsberget wind farm, may be that the reindeer need to be supplementary fed and intensively herded to keep the reindeer in the area, subsequently increasing the work load on the reindeer herders. It also reduces the ability of herders to mitigate extreme weather by moving reindeer to dwindling alternative grazing sites.

    Other infrastructure, such as roads and power lines, also affect the reindeer habitat selection. Prior to wind farm development, reindeer avoided areas in the vicinity of larger (>5 m wide) roads. After the wind farm was developed, the reindeer at Stor-Rotliden stopped avoiding the large roads and instead increased the habitat use closer to the large roads in the only alternative foraging areas. At Gabrielsberget, the reindeer also used areas close to the large roads, including the highway E4, when the reindeer were freely ranging in order to avoid the wind farm. This obviously increases the risk of traffic accidents and herders are subsequently required to intensify herding.

    Mitigation measures for herders and developers in areas where wind farms are already established are presented. Especially, established associated road infrastructure to the windmills should be closed for public use to avoid recreational activities, whether by ATVs or snowmobiles, or by hunters. Furthermore, a close contact should be maintained between the power company and the reindeer herding community to prevent road or mill maintenance work during sensitive periods for the reindeer. Other more regional measures to facilitate reindeer movement and migration between different grazing ranges may be to establish fences along major roads and railways (eg. E4 or the main railroad through Sweden) combined with strategically placed ecoducts.

  • 44.
    Stattin, Eva
    et al.
    Dalarna University, School of Technology and Business Studies, Forest and Wood Technology.
    Lindström, Anders
    Dalarna University, School of Technology and Business Studies, Forest and Wood Technology.
    Nathalie, Verhoef
    Balk, Peter
    Quality management for vital forest tree seedlings: Final report, Project no: P33854-12011Report (Other academic)
    Abstract [en]

    The work concerns development of a prototype molecular tests to identify vitality status of conifer seedlings. The work is done by NSure, Holland, Dalarna University and SUAS. In case for spruce, a successful validation experiment has been performed to validate the identified frost tolerance and vitality genes. Multiple indicators were identified that can be used to either reinforce the existing ColdnSure test, but also for development of a vitality test. The identified frost tolerance and vitality genes for pine still need to be validated. NSure together with Dalarna University aim to perform a validation next season. Multiple LN indicators were identified in spruce that can be used to determine the effectiveness of a LN treatment, but they are not yet validated. In spruce and pine hardly any scientific research is performed to study the effect of a LN treatment, particularly not at molecular level. Therefore NSure together with Dalarna Research Station want to apply for a project. Within this project, we would be able to develop the tests further.

  • 45.
    Stattin, Eva
    et al.
    Dalarna University, School of Technology and Business Studies, Forest and Wood Technology.
    Verhoef, Nathalie
    Balk, Peter
    van Wordragen, Monique
    Lindström, Anders
    Dalarna University, School of Technology and Business Studies, Forest and Wood Technology.
    Development of a molecular test to determine the vitality status of Norway spruce (Picea abies) seedlings during frozen storage2012In: New forests, ISSN 0169-4286, E-ISSN 1573-5095, Vol. 43, no 5-6, p. 665-678Article in journal (Refereed)
    Abstract [en]

    In boreal forest regions, a great portion of forest tree seedlings are stored indoors in late autumn to prevent seedlings from outdoor winter damage. For seedlings to be able to survive in storage it is crucial that they store well and can cope with the dark and cold storage environment. The aim of this study was to search for genes that can determine the vitality status of Norway spruce (Picea abies (L.) Karst.) seedlings during frozen storage. Furthermore, the sensitivity of the ColdNSure (TM) test, a gene activity test that predicts storability was assessed. The storability of seedlings was tested biweekly by evaluating damage with the gene activity test and the electrolyte leakage test after freezing seedlings to -25 A degrees C (the SELdiff-25 method). In parallel, seedlings were frozen stored at -3 A degrees C. According to both methods, seedlings were considered storable from week 41. This also corresponded to the post storage results determined at the end of the storage period. In order to identify vitality indicators, Next Generation Sequencing (NGS) was performed on bud samples collected during storage. Comparing physiological post storage data to gene analysis data revealed numerous vitality related genes. To validate the results, a second trial was performed. In this trial, gene activity was better in predicting seedling storability than the conventional freezing test; this indicates a high sensitivity level of this molecular assay. For multiple indicators a clear switch between damaged and vital seedlings was observed. A collection of indicators will be used in the future development of a commercial vitality test.

  • 46.
    Wallin, Elisabeth
    et al.
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Gräns, Daniel
    Stattin, Eva
    Dalarna University, School of Technology and Business Studies, Forest and Wood Technology.
    Verhoef, Nathalie
    Mikusiński, Grzegorz
    Lindström, Anders
    Evaluating methods for storability assessment and determination of vitality status of container grown Norway spruce transplants after frozen storage2019In: Scandinavian Journal of Forest Research, ISSN 0282-7581, E-ISSN 1651-1891Article in journal (Refereed)
    Abstract [en]

    Autumn sown small seedlings for later transplanting into large containers have been introduced in Swedish forest tree nurseries. Containerized transplants of Norway spruce (Picea abies (L.) Karst.) from three Swedish nurseries were frozen stored during the autumn of 2014 to find out storability and post-storage vitality. Seedling storability was determined by measuring electrolyte leakage after freezing shoots to −25°C (SELdiff−25), by measurements of dry matter content (DMC) of seedling shoots and by the commercial molecular test ColdNSure™. Vitality of seedlings after storage was determined by measuring the leakage of electrolytes from shoots (SEL), and seedlings were also tested in regrowth tests. All three methods for storability assessment gave similar predictions, except in one case where DMC showed “not storable” for successfully stored seedlings. Our results indicated that young transplants can be successfully short term stored before reaching the target levels for safe long-term storage of conventional seedlings. Early storage of young transplants resulted in low post-storage survival and vitality expressed as root growth capacity and shoot electrolyte leakage (SEL). A prolonged duration in storage generally resulted in lower survival as well as lower root growth capacity and higher levels of SEL, especially for seedlings stored at earlier dates. 

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