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170 Uppsatser om Spruce - Sida 2 av 12
Anva?ndning av markfuktighetskartor fo?r sta?ndortsanpassad plantering
Digital depth-to-water maps can be produced from a digital elevation model (DEM). Then GIS- based algorithms are used to calculate water flows and the depth-to-water index classes dry, fresh, moist and wet. The purpose of this study was to investigate the possibility to use depth- to-water maps for site adapted planting.The results showed that use of depth-to-water maps for site adapted planting, roughly halved the proportion of improperly planted surfaces from an average of 9 % to 4 %. The variation in the values of proper surface decreased and the result became more even.. In addition, more pine than Spruce was incorrectly planted.
Precommercial thinning stumps´susceptibility to Heterobasidion spp : a comparison between high and low Norway spruce and birch stumps : a measuring of the efficacy of Phlebiopsis gigantea stump treatment
Each year, Heterobasidion spp. is a major cause of economic losses to forestry in the northernhemisphere, including Sweden. New results indicate that pre?commercial thinnings could be at riskfor Heterobasidion spp. infections.
Fortsatt gran eller självföryngrad björk efter stormfällning? : en ekonomisk analys
The southern part of Sweden, Skåne, is frequently exposed to storms causing great damage to Norway Spruce (Picea abies L. Karst.) stands. A storm during the winter 1999/2000 raised the attention of the problem. A lot of forest owners got large areas of Spruce stands wind thrown during this storm. Can naturally regenerated birch (Betula sp.) be an alternative on these wind-exposed sites? This was the main question I was facing when discussilig the problems with Esben Möller Madsen, Söderåsens forest district.
The aim of this master thesis was to present an economic analysis of Norway Spruce versus
birch.
Överlevnad, tillväxt och skador i planteringar av sitkagran (Picea sitchensis) efter stormen Gudrun
Sitka Spruce (Picea sitchensis (Bong.) Carr) is just like Norway Spruce (Picea abies) a species in thegenus picea. The natural range of Sitka Spruce is a narrow strip along the west coast of North America. Itis the most coastal of all picea species, and very dependent on the mild and humid climate along thepacific coast.Sitka Spruce has been grown a long time in the countries around the North Sea, particularly in GreatBritain where it currently is the most important species in British forestry. Sitka Spruce has not beenplanted in Swedish forests to any large extent before the storm Gudrun in 2005. Several studies indicatethat the production of wood biomass is higher for Sitka Spruce compared to Norway Spruce.
Vindskador vid stickväg i 1:a och 2:a gallring i Boxholm, Östergötland : i stormen Pers fotspår
Wind damages next to strip roads in 1st and 2nd thinning in Boxholm, Östergötland
Anneli Fransson, SLU, inst f sydsvensk skogsvetenskap, Examensarbete no 108
Wind damage is something we are all familiar with since the storms Gudrun (2005) and Per (2007). Research about strip roads and wind damage is very limited. It is commonly known that the trees next to the strip roads more often fall whit heavy winds, and the purpose of this thesis was to verify this statement. Data was collected from first- and second thinnings at Boxholms Skogar AB, Östergötland. In first thinnings data was collected from both Spruce and pine stands and second thinnings only data from Spruce stands was collected.
Granproduktion på tallmarker! : är produktionen hållbar?
The aim of this report was to investigate the hypothesis that Norway Spruce (Picea abies L. Karst), planted on poor ?Scots pine? stands will not have sustained growth during the whole rotation, due to water deficit in the closed stands. In order to investigate this hypothesis, data from 10 Norway Spruce stands in southern-eastern Sweden were collected. In 10 plots in each stand, diameter and breast heights were measured on every tree.
Skogssådd med tall och gran : effekter av fröegenskaper och skärm/hygge på plantbildning, överlevnad och tillväxt de två första åren efter sådd
Over the past few years the Swedish forestry industry has become increasing interested in direct seeding. Although, in practice, this interest has been restricted to pine seed, the knowledge and techniques that have been developed for pine seeding can readily be transferred to Spruce. Direct seeding is a method that is of interest to the forestry industry since it can lead to lower regeneration costs, denser stands and better root development than the more conventional planting method.
This study evaluated experiments that focused on direct seeding of Spruce in the northern Sweden. Skogforsk set-up the experiments in Gideå and Sävar in 2003.
Urvalsdesign för SCB:s undersökning av föetagens ekonomi
Tree fiber lengths controls properties like strength and smoothness in paper and other wood products. For forest researchers it is of interest to be able to determine the fiber lengths in standing trees. Mo?rling et al. (2003), among others, have developed methods to estimate fiber length distributions in standing trees without damaging them.
Om matematikundervisningens svåra konst. Ett sätt att undervisa abstrakt bevisföring
Tree fiber lengths controls properties like strength and smoothness in paper and other wood products. For forest researchers it is of interest to be able to determine the fiber lengths in standing trees. Mo?rling et al. (2003), among others, have developed methods to estimate fiber length distributions in standing trees without damaging them.
Analys av fiberlängdsfördelning hos gran (Picea Abies) och tall (Pinus Sylvestris)
Tree fiber lengths controls properties like strength and smoothness in paper and other wood products. For forest researchers it is of interest to be able to determine the fiber lengths in standing trees. Mo?rling et al. (2003), among others, have developed methods to estimate fiber length distributions in standing trees without damaging them.
Risken för spridning av röta vid förröjning i granskog i södra Sverige :
Root rot causes large economical losses for Swedish forestry. The spread of root rot can partly be prevented by treating the Spruce stumps in thinnings. Late pre-commercial thinning (PCT) is one of the forestry measures where stump treatment is not used. Late PCT can be defined as: The act of cleaning the stand with the aim of improving accessibility and sight within the stand, and so to increase the mean stem´s volume during the first conventional thinning.
The aim of this study was to examine how late PCT is performed, its spatial extent and if it aids the spreading of root rot. The study was limited to encompass late PCT before first conventional thinnings in Spruce stands in southern Sweden.
Samples of Spruce stumps were taken from four stands where late PTC had been carried out.
Ekonomiska konsekvenser av förändrad röttolerans vid Bravikens Pappersbruk :
The competition for Norway Spruce pulp wood in Central Sweden increases, forcing the supply-structure of Holmen to face two important challenges. Firstly, it is of the outmost strategically importance to secure the long-term supply of Norway Spruce pulp wood to the industries. Secondly, Holmen desires to increase the obtainable volume of Norway Spruce pulp wood. This would enable the company to choose volumes in the lower price-segments and thereby decrease the dependency of costly marginal volumes.
As this work shows, one part in managing these challenges could be to lower the quality standards concerning root rot (Heterobasidium annosum).
Facts presented in the work shows that:
1. Technically, the TMP-industry of Braviken can handle a much more rotted pulp wood than that used today, although the cost of refinement increases.
Volume and taper equations for Sitka spruce (Picea sitchensis (Bong.) Carr.), Norway spruce (Picea abies (L.) Karst.) and White spruce (Picea glauca (Moench) Voss) in Iceland
The aim of this study was to evaluate different types of volume and taper equations that can be used to predict single-tree stem volume and stem diameter at any given height along the tree stem for plantation grown Sitka Spruce (Picea sitchensis (Bong.) Carr.), Norway Spruce (Picea abies (L.) Karst) and White Spruce (Picea glauca (Mounch) Voss) in Iceland. A number of published tree volume equations were tested and modified to predict the total stem volumes over bark but three logarithmic equations were taken for more in-depth analysis. Three taper equations were tested. Two variable-exponent equations (Kozak 1997, Kozak 2004) and one exponential equation described by Biging (1984). Data from a total of 617 sample trees were used in this study, collected from stands in various parts of the country and present different types of stands growing in different soil types and cover most of the site conditions suitable for forestry in Iceland.
A comparison of methods to assess site index in young Norway spruce stands
This study investigates whether the site index curve method (SICM) and the growth intercept method (GIM) can be used for site index predictions in younger Norway Spruce (Picea abies (L.) Karst.) stands than recommended by current guidelines. For SICM it was thus investigated whether the method could be used for stands younger than ten years, and for GIM it was tested whether a starting point for the intercept measurements could be used below the recommended
2.5 meter. This was tested based on measurements taken from experimental stands in Tönnersjöheden Research Forest.
For GIM it was found that the method can only be used when the TH-trees of a stand have five complete intercepts above 2.5 meters. For the method to be applicable beyond this, it will be necessary to adapt the underlying equations, perhaps following the Canadian example where a 1.3 meter intercept start is used. In conclusion it is not currently possible to apply the approach beyond the current recommendations.
For SICM, SI predictions are accurate for the study area already form year three.
Modeller för brösthöjdsålder för tall och gran :
The purpose of this study was to develop two types of prediction models for Scots Pine
and Norway Spruce. The first type for calculation of the stump diameter under bark the
year the tree reached breast height (Dstubh130). The second type for calculation of the
annual difference, e.g. the number of growth years between stump height (0.2 m) and
breast height (1.3 meters above ground level). The primary thought with these prediction
models is to obtain the breast height age in the trees on basis of the number of annual
rings at stump.