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83 Uppsatser om Pieca abies - Sida 2 av 6

The effect of arginine on root system development in Norway spruce (Picea abies L. Karst) somatic embryos

The demands for higher production yields and better quality materials from the forests are increasing globally. Tree breeding programs are directed to meet the future demands on forests. In order to capture the full benefits from the breeding programs, clonal propagation is necessary. For most conifer species, somatic embryogenesis (SE) is the only available option for large scale clonal propagation of Elite clonal material. For Norway spruce (Picea abies L.

Stump treatment with the root rot antagonist phlebiopsis gigantea : - sensitivity of P. gigantea spores to high pressure stress; - reduced water consumption for stump treatment

Stump treatment today requires large quantities of clean water mixed with the protective product Rotstop, to fully cover the stump surface. In order to reduce the water consumption without reducing the coverage of the stump surface, the pressure in the stump treatment device can be increased. Therefore, the Phlebiopsis gigantea (Fr.) Jül. suspension used as a biological control agent to prevent Heterobasidion annosum (Fr.) Bref. infection was pressure-tested.

Odlingserfarenheter av kustgran (Abies grandis) i Sverige

Kustgranen är ett snabbväxande trädslag som härstammar från nordvästra Nordamerika. IEuropa odlades den första gången i England och har sedan dess introducerats i fleraeuropeiska länder. I Danmark är kustgranen inte så ovanlig och odlas där främst längskusterna. I Sverige är kustgranen däremot väldigt ovanlig och odling har endast skett på ettfåtal lokaler i södra Sverige. Intresset får sägas vara mycket lågt för detta trädslag i Sverigetrots att det bevisligen kan producera väldigt bra här.

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.

Increased growth in Norway spruce (Picea abies (L.) Karst.) through small annual additions of nitrogen (N) fertilizer

This project investigated how elevation and vegetation type influences variation in plant litter phenolic content and protein precipitation capacity among and within common plant species for two different vegetation types, heath and meadow, in a subarctic ecosystem in the Abisko region of northern Sweden. As nutrient availability generally decreases with increasing elevation as a result of decreasing temperature, I hypothesised that phenolic content would increase with elevation and be higher on the heath than the meadow. To test this, the total phenolic content and protein precipitation capacity was estimated in leaf litter from 13 species in both heath and meadow vegetation across an elevational gradient ranging from 500 to 1000 meters above sea level (m.a.s.l.) in the study region. The results showed that elevation and vegetation type both had a strong impact on both variables. Total phenolic concentrations decreased with elevation for the meadow, and were greater for the heath than the meadow.

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.

Plantering av barrplantor på hösten : överlevnad och tillväxt

Detta arbeta har utförts för att undersöka hur höstplantering av täckrotsodlad gran (Picea abies) och tall (Pinus sylvestris) överlever och utvecklas jämfört med vårplanterad. Detta i ett led för att se om man kan utöka planteringssäsongen för att få en jämnare arbetsbelastning över säsongen både i plantskolorna och ute i fält. Man har undersökt hur en planteringstidpunkt på sensommaren och hösten påverkar granplantors överlevnad jämfört med plantering på våren. Studien är utförd som en survey studie i södra Sverige på täckrotsplantor av gran som planterats på medelboniteter 2007-2009 och inventerats 2010. Höst och vårplanterade granplantor är jämförda parvis med samma planttyp, ålder, proveniens och geografiskt område.

Factors affecting bark-stripping by red deer (Cervus elaphus) : the importance of landscape structure and forage availability

Bark-stripping by red deer (Cervus elaphus) cause extensive damage to economically valuable spruce trees (Picea abies) in Swedish forests. The underlying causes for bark-stripping are not fully understood, and the frequency and severity of damage unpredictably differ between regions. In this study, I investigated if landscape structure (e.g. agricultural dominated landscape opposed to forest dominated landscape), forage availability, population density and disturbance (e.g. roads and settlements) affect bark-stripping frequency.

Stormskador i lärk och gran : en jämförelse efter stormen Gudrun

The storm Gudrun January 8-9 2005 felled about 70 millions cubic metres forest in southern Sweden. The majority of the wind damaged forest was spruce (Picea abies). In order to decrease the risk of wind damages in the future other trees species are of interest for forestry in southern Sweden. The purpose of this master thesis was to study if larch were more wind tolerant than spruce. The method was to compare larch, Japanese larch (Larix kaempferi Lamb.), European larch (L.

Omvandling av granskog till ädellöv i södra Sverige ? fallstudier från Söderåsens nationalpark och Raslångens ekopark

I Sverige och stora delar av Europa har det planterats gran, Picea abies, på marker som tidigare varit lövdominerade. Idag restaureras ädellövskog på dessa marker i ökad omfattning, bland annat för att gynna skogens biologiska mångfald och rekreationsvärden. Syftet med detta arbete var att undersöka överlevnad och tillväxt av ek, Quercus robur, och bok, Fagus sylvatica, som planterats efter gran i Söderåsens nationalpark och i Raslångens ekopark i södra Sverige. I Söderåsens nationalpark undersöktes plantutvecklingen tio år efter plantering på öppna hyggen (ek och bok) eller under björkskärm (bok). För Raslångens ekopark var syftet att undersöka om inversmarkberedning och hägn påverkar initial etablering och överlevnad hos bokplantor på öppna hyggen. Resultaten från Söderåsen visar att ek och bok tio år efter plantering kan nå en hög överlevnad och god tillväxt med hjälp av fungerande hägn och regelbundna röjningar.

Barrandel och fukthalt i färsk grot från gran i södra Sverige

Skogen är en förnyelsebar energikälla som möjliggör för ett minskat beroende av fossila bränslen. Ur ett politiskt perspektiv minskar såväl klimatpåverkan som beroendet av importerad energi från oroliga delar av världen genom att ta tillvara skogsbränsle lokalt. I Sverige är sågverkens biprodukter fullt utnyttjade och därför har skogsbränsle i from av grot (GRenar Och Toppar) en av de största potentialerna till ökat uttag.Barrträdens barr är en omstridd fråga i samband med tillvaratagandet av grot. Barren står för en liten del av biomassan, men för en stor del av näringen i ett bestånd. Därför är det önskvärt att så mycket som möjligt av barren lämnas på föryngringsytan.

Picea mariana ((P. Mill.) B.P.S), P. abies (L.), Pinus contorta (Dougl.) och P. sylvestris (L.) : en jämförelse av produktion och potentiell kvalitet hos försöksbestånd i Jämtlands län

Swedish forests are dominated by just two conifer species Norway spruce and Scotch pine. They are not able to achieve the highest possible production or fulfill industry demands for raw materials. The introduction of exotic conifers can potentially meet these shortcomings and present a relevant solution. This study was conducted in a block experiment with ten blocks planted in 1987 by SCA in North Sweden. The objective of the block experiment was to study if Black spruce is an appropriate alternative to Lodgepole pine, Norway spruce and Scotch pine on different site classes.

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.

Vinster med björkinblandning i granbestånd i syfte att höja markens pH-värde

The soil acidification and the pH-value of the soil have been discussed for many years. Many observations of the tree species effects on the soil pH have been done. We have discussed the effects on the soil surface pH-value with a birch (Betula spp. L.) admixture in Norway spruce stands (Picea abies L.).We have used data from the Swedish National Forest Inventory. We have also discussed how the wood production and the biodiversity can be increased in mixed stands, in according to the Swedish forestry act Skogsvårdslagen. Our sampling areas are located in Norrland, Sweden. The results show a significant correlation between an increased birch admixture and an increased pH-value of the soil.

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.

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