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87 Uppsatser om Picea abies - Sida 1 av 6

Diameter- höjdskillnader för klippgran (Abies laciocarpa), gran ( Picea abies), glasbjörk (Betula pubescens) och contorta (Pinus contorta) i Strömsunds kommun.

Det finns ett stort intresse för exoter inom skogsbruket och i denna rapport behandlas klippgran (Abies laciocarpa) och Contorta (Pinus contorta). Vid undersökningen av dessa trädsorter jämfördes diameter och höjdtillväxt med gran (Picea abies) och björk (Betula pubescens). Mätningarna utfördes på lokaler i Strömsunds kommun i Jämtlands län vid Näxåsen (Strömsund) och runt Jorm i Frostviken på SCA:s marker.

Sitkagranens potentiella merproduktion jämfört med vanlig gran i Hallands län

Sitka spruce (Picea sitchensis) is not considered to be a native species to Swedish forests. It´s origin is the pacific coast of Northern America, an area that is dominated by a coastal climate which makes it likely to believe that it would be well suited for growing in the south-west of Sweden. This study aims to investigate the gain in production that can be reached by growing sitka spruce instead of Norway spruce (Picea abies) in the county of Halland. A regression model based on data from forest experiments was produced to explain the gain in production. This model was based on elevation and annual precipitation. The model was then used to create a map layer in arcGIS that shows the gain of volume in comparison to Norway spruce in percent. An analysis was carried out to find what share of the forestland in Halland county that fell into four different classes of production gain.

Förändringen av tall- och granbestånden i eklandskapet söder om Linköping, 1927 jämfört med 2013

The aim of the study was to compare how the population of pine (Pinus sylvestris) and spruce (Picea abies) have changed between 1927 and 2013 in the oak landscape south of Linköping. A field study was carried out in 22 two kilometre lines which also had been studied in 1927. In these lines, which where ten meters broad and had a direction from west to east, the pines and spruces were counted, measured and classified by steam diameter. The obtained result was that the basal steam area (m²/ha) had increased for pine (44%) and spruce (57%) between 1927 and 2013. The amount of trees had increased in all diameter classes except thinner pine and spruce with a diameter of 5-10cm.

En fallstudie av en gallringsfri skötselmetod för gran i Västra Götaland

Resultat från 3 olika bestånd i Västra Götaland. Åldern på bestånden är 30, 50 och 50 år. Varje provyta var 100 m2. Bestånden har vuxit utan gallring och gödsling och skötts enligt en metod som kallas Hyssnametoden. Syftet med studien var att beskriva, följa upp och utvärdera effekterna av en alternativ skogsskötselmetod.

Kloridhalter i gran utmed en depositionsgradient för havssalter :

The knowledge of the chloride content and its fluxes and patterns in trees is insufficient. Increased knowledge would be desirable, one of many reasons is to be able to more efficiently meet the problems that the substance causes in the pulp industry. The purpose of this study was to examine and describe the chloride concentration of Norwegian spruce (Picea abies L. Karst.) in the south of Sweden. Furthermore the aim was to be able to predict chloride concentration from readily measurable site factors.

Beståndsutveckling i stormskadade granbestånd

The storm Gudrun in 2005 led to massive windthow damage in forests in southern Sweden. Since then there has been a growing interest in factors influencing wind damage in above all Norway spruce (Picea abies) stands. Although many other interesting areas still need to be examined. In 2005 there where a lot of stands that suffered different degrees of damage, a lot of these stands weren?t cut, but instead left to grow. The future development of these stands is uncertain and the guidelines are unclear.

Algbiomassa som gödselmedel till gran och tall

För att växter ska växa bra krävs det en mix av olika näringsämnen där de två viktigaste näringsämnena normalt sett är kväve (N) och fosfor (P). Det är viktigt att mixen av olika näringsämnen passar växtens behov samt att näringsämnena är möjliga för växten att ta upp. Det får inte heller vara för mycket av ett näringsämne då detta kan leda till förgiftning. Denna studie är gjord med syfte att klargöra hur algbiomassa av grönalger i blandad mix fungerar som gödslingsmedel för små plantor av tall (Pinus sylvestris) och gran (Picea abies). Samt att hitta förklaringar över varför algerna påverkar plantornas tillväxt.

Tjäderns (Tetrao urogallus L.) vinterdiet i norra Sverige : är gran (Picea abies) viktig i vissa habitat?

In Scandinavia, capercaillie are often associated with pine trees (Pinus sylvestris) in winter, with pine needles as the main diet. Few dietary studies have been conducted in Sweden and winter diet is subject to little debate. The interesting thing is that this "pine specialist? is also found in spruce (Picea abies) forest habitats where pine is scarce or unavailable. In many studies outside Sweden (primarily Central Europe) spruce is regularly observed in the winter diet, but I have found no reports on the selection of the diet in spruce forest areas in Sweden.

En jämförelse av sitkagranens (Picea sitchensis) och den vanliga granens (P. abies) produktion :

Sitka spruce (Picea sitchensis) is a tree species that have its natural distribution along the West Coast of North America, from Alaska in the north to northern California in the south. Sitka spruce is a typical coastal tree species that can reach heights up to 85 meters and occurs in single pure as well as in mixed stands. The main purposes of this study were to describe the Sitka spruce growing characteristics and the volume production in comparison to spruce (Picea abies). The possibility to predict future volume production by using prognosis tools designed to be used on spruce were also studied. The material that has been used in this study are permanent sitka trials established by the Faculty of Forestry fixed Sitka trials and also material gathered in this study. A literature study was also carried out in order to determine the Sitka spruce growing characteristics. Sitka spruce has a high adaptation and a high volume production on a broad scale of soil types. The tree species is a pioneer species that has a fast early growth and in combination with sharp needles it is less susceptible to animal browsing than spruce. The factor that is the single most limiting factor for where the Sitka spruce can be planted is frost. This factor can be limited by using plant material with a well-suited provenance. According to the literature, the Sitka spruce has an average total volume production that is between 20-40% higher than spruce.

Julgransodlingar i Sverige : utbud, efterfrågan och lönsamhet

This thesis is about Christmas tree plantations in Sweden, and if its profitable to produce Christmas trees in Sweden. Sweden has 4,3 million households, 3 million of these households buys Christmas trees. 80 % of these Christmas trees are Norway Spruce (Picea abies), which is the most common Spruce in Sweden. Every year over 170 000 Christmas trees are imported to Sweden. The main import comes from Denmark.

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.

Vedlevande lavar på döda grenar på levande träd i produktionsskog

Saproxylic lichens in managed forests have less substrate available than in unmanaged forests due to the shortage of dead wood. However, a suitable substrate for these lichens could be dead branches on living trees. To this date, there has not been any systematically collected data about theabundance of dead branches on living trees and the lichens growing on these branches in managed forests. The aim of this study was to see where dead branches were located on living trees of Pinus sylvestris and Picea abies, how large the surface area of these branches was and what lichens grewof wood on these branches. The study was made in Finspång, Sweden, where 11 forest stands of P.sylvestris and P.

Elementkoncentrationer i gran utmed en markfuktighetsgradient :

One key factor in silviculture today is sustainability. In order to achieve sustainability it may be important to restore lost nutrients to the forest after clearcutting. In order to calculate the removal, you need to know how much of different elements you will find in different tree compartments. The aim of this study was to investigate if the concentration of elements in different tree compartments of spruce (Picea abies (L.) Karst) were related to the moisture conditions of the site. Five plots at Risfallet (60º 21´ N, 16º 13´ E), was placed along a moisture gradient in a 40- year spruce stand.

En utvärdering av hur olika metoder i Skogshögskolans boniteringssystem påverkar skattningen av ståndortsindex

Det för skogsbruket viktiga boniteringssystemet grundas på skattningar av ståndortsindex (SI). SI beskriver markens naturgivna produktionsförmåga genom att ge en skattning av hur höga de grövsta träden kommer att vara vid en referensålder. I detta arbete jämfördes metoder för att skatta ståndortsindex med ståndortsegenskaper (SIS) med äldre respektive nyare formler för skattning av ståndortsindex med övre höjd och höjdutvecklingskurvor (SIH). Detta utfördes genom analyser av data från svenska långtidsförsök med gallring och gödsling (GG-försöken) rörande tall (Pinus sylvestris) och gran (Picea abies). Resultaten visade statistiskt signifikanta skillnader mellan äldre och nyare formler för SIH på tall men inte på gran.

Productivity of Norway spruce (Picea abies) and Scots pine (Pinus sylvestris) in coastal areas of northern Sweden

Productivity of Norway spruce (Picea abies) and Scots pine (Pinus sylvestris) was studied on 12 sites in coastal areas of northern Sweden. On each site, sample plots were placed in adjacent Norway spruce and Scots pine stands with similar ages in between. Basal area, tree height, Site Index, volume production, simulated maximum mean annual increment (MAImax) and tree vitality were compared for the two species. Average basal area at the time of measurement was 30.4% larger for Scots pine stands than for Norway spruce stands. The difference between the two species in basal area increment during the last 10 years was related to stand age.

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