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311 Uppsatser om Norway spruce - Sida 6 av 21
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.
Effekter av landskapets sammansättning på humlearters förekomst
The species in the genus bumblebees (Bombus) are important pollinators. In the world there are 250 bumblebee species and there are 34 species in Norway. The purpose of this study is 1) to assess changes in the species composition of bumblebees in twenty different places in Norway that have been inventoried first one time between 1939-1960 and the second time in 2012, and 2) to relate species richness and distributions to current landscape composition with the aid of orthophotos. In this study, I have used regression analyzes on the different bumblebee species that were present or absent at the inventory, using the premises of the following variables: low or high altitude, latitude, longitude and seven different types of land use (farmland, building/plots, open land/pasture, forest, wetland and open or snow-covered ground above the tree line) to see if there was any relationship between each species and the different variables.
I have not analyzed what the landscape looked like at the first inventories and therefore we cannot say whether it has changed and if that is why species number has decreased. This would be interesting to study further and to see if there is any relationship between landscape changes and bumblebee?s species decline.
Artificiell insemination av får
AbstractThe purpose of this bachelor thesis is to describe the use of artificial insemination (AI) in sheep and discuss the possibilities for AI in Sweden. Male and female fertility, heat detection, semen handling and insemination techniques in sheep are described. Advantages and disadvantages of AI are discussed. In order to achieve genetic progress it is important with well planned and implemented breeding programs. The Swedish Sheep Recording Scheme and computer software from Elitlamm are the basis for sheep breeding in Sweden.
Kronunionens återkomst : En empirisk underso?kning av konjunkturscykler, arbetskraftsro?rlighet och handelsintegration fo?r att avgo?ra mo?jligheten att info?ra en gemensam valuta i Norden
This paper is an assessment of whether the Nordic countries constitute an optimum currency area (OCA) or not. Hodrick Prescott-?filtered data of real Gross Domestic Product (GDP) and rate of employment are used to investigate the similarity of business cycles between the target countries through a series of correlation analysis with Sweden as the base reference country and also by using a linear regression model. Additionally there is an evaluation of trade volume and labour mobility between the countries. Our results indicate that Iceland had the least similar business cycles within the Nordic countries and that the area should therefore possibly comprise Denmark, Finland, Norway and Sweden. .
Plantering av gran (Picea abies) på kalhyggen och självföryngring under högskärmar av björk (Betula pendula och Betula pubescens) : föryngringsresultat 7-10 år efter avverkning
The aims of the silvicultural method natural regeneration of spruce (Picea abies L. Karst) in birch (Betula pendula and pubescens) shelterwoods are to establish a new stand of tree seedl-ings and to protect those from high groundwater levels, frost damages and grass competition during its first life years.
The aim of this work has been to (i) describe how shelterwood and stand characteristics influ-ence the results from using natural regeneration of spruce protected by a shelterwood of birch, and to (ii) compare those regeneration results with planting of spruce after soil scarification in clear-cut areas.
Totally 17 harvesting sites have been inventoried and 15 of those included natural regenera-tion in birch shelterwoods, and two were subjects to soil scarification and planting of spruce. The sites represented 7-10 year old final cuts and are located in the coastal (eastern) region of the province of Norrbotten in Sweden. In all areas shelterwood and stand characteristics, as well as the number of main crop seedlings and the height of the highest main crop spruce seedling, were estimated and registered in all areas.
Produktivitet vid stubblyftning :
Stump wood was used between 1850 and 1950 for production of tar and as firewood. In the 1950s the use decreased because of the introduction of the cheap fossil oil. In the 1970s stump wood became an interesting issue again as a raw material for the pulp industry. Stump lifting has today become a possible source for bioenergy. The objectives with this study were to investigate the productivity of stump lifting and stump extraction, and to analyse the economy.
Röjningsförbandets betydelse för avverkningsekonomin i södra Sverige :
The aim of this work is to demonstrate how the net present value (NPV) at the time of the first thinning depends on the spacing after pre-commercial thinning, and show how net value from first thinning in same stand is influenced.
This study is performed with models based on non-distant dependent growth models for single trees. Two different growth models have been used, one for cleaning (pre-commercial thinning) and one for thinning. The first one yields stem density distributed over diameter classes. In the second one, (the thinning model), it is possible to choose when thinning should be done, the thinning method, thinning grade and numbers of thinning.
?dn?ris?: att b?ja st?nger till t?ltk?ta
This thesis is my exploration of the immaterial heritage that is the craft of bending of ?dn?ris?
out of spruce. It?s a broken tradition that is scarcely described, mainly through Yngve Ryd?s
report T?ltk?tor (1999) that contains interviews with two knowledge keepers, Nilas Tuolja
and Johan Rassa. Yngve Ryd?s report went against the earlier opinion by the mid 20th century
ethnologist Ernst Manker who claimed that they were only made exclusively out of mountain
birch that has curved growth.
As a background, I discuss the special importance of heritage conservation, both material and
immaterial, in a S?mi context as being an indigenous people.
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.
Thuja plicata - etableringsförsök av jättetuja med fyra olika provenienser
Future climate changes may lead to an interest of alternative and foreign forest tree species in order to spread the risks in forestry. Douglas fir, Sitka spruce, Freemont cottonwood and hybrid aspen are examples of popular foreign tree species that along with western red cedar could have a future in the Swedish forests.Södra Skogsägarna and SLU have collaboration in establishment of foreign species in Swedish forests.The purpose of this study was to analyze and present the establishment of western red cedar, and to survey and illustrate injuries of freeze drying and other damages like deer browsing, vegetation and insect attacks. The study included four different provenances, and spruce as a reference, planted in two locations ? Asa and Släne.Western red cedar is despite its name a conifer of the cupressaceae family with defined secondary characteristic and gets along well with an overstory. Western red cedar grows often in mixed stands with similar conifers and its natural habitat is within and in the area near to British Columbia.The study included two series of field inventories, one made in the summer and one in the autumn 2013, three growing seasons after plantation.
Fuktkvotens inverkan på oljeupptag och pigmentinträngning i tall (Pinus sylvestris L.) och gran (Picea abies L. Karst) vid impregnering med Linotechmetoden :
Wood has always been an important material for people, and it is used for many applications. As for example, fuel for cooking and heating houses, construction materials and for constructing means of transport. Since wood also is a material that with time biologically degrades due to activity by micro organisms and wood fungi it is important to find ways to protect and further lengthen the life span of the material when in service. One method is to decrease the amount of water in the material by impregnation with an hydrophobic oil. The Linotech method which uses only pure linseed oil is one such possible method.
The aim of this study was to investigate the possibility to at the same time impregnate and stain/colour wood samples of pine and spruce by using the Linotech method.
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.
Skötselmetoder för bestånd med produktions- och naturvårdsmål :
This study is made on assignment by the local board of forestry in Skåne,
Blekinge and Halland.
The change of the forest law 1994 brought a new type of management plan.
A more active planning was introduced in order to equate the environment goal
with the production goal. The purpose with this study is to give a better picture of
how planning for nature conservation in production forest is made and to develop
support for selection of silviculture methods for stands with combined goals. With
combined goals means production forestry with a reinforced consideration to both
nature and culture, called PF-classified stands. This was done by:
? Describing silviculture models from the literature that are possible to use
for stands with combined goals.
? Describing silviculture models that is used in practice in stands with
combined goals.
? Describing how the classification of stands with combined goals is used.
Which means, were in the terrain, with which frequency and in which type
of forest PF-classification is used.
? Comparing differences and similarities of theoretical and practical used
models.
The study was done partly as a literature study and partly as an interview study of
forest planners.
Vindfällning, tillväxt och plantuppslag i en 13-årig granskärm i Medelpad :
The interest for alternative forest regeneration methods increased significantly during the 1990´s after 50 years dominance of the clear-cutting system (Holgén & Hånell 2000). One reason for this was that clear-cutting was being more and more questioned by different envi-ronmental organizations and because the forest sector for economical reasons wanted to find cheaper ways to regenerate forests. In the beginning of the 1990´s two shelterwood experi-ments were established in a joint effort by Svenska Cellulosa Aktiebolaget (SCA) and the Dept of Silviculture, Swedish University of Agricultural Sciences (SLU). The experiments include various forms of cutting and shelterwood densities and represent productive spruce forests in central and north Sweden (Roggsjön in the province of Medelpad and Skikkis-jöberg in the province of Västerbotten, respectively ). The experiment next to Roggsjön has been reported earlier in three MSc theses, and is also the focus of this thesis.
Det norska energideklarationssystemets konsekvenser för äldre byggnaders karaktärsbärande värden
Roughly 130 000 dwellings have been officially registered since Norway as of summer 2009 passed their bill ?Energimerkeforskriften? on energy performance certificates in buildings. The main objective is to decrease the total amount of national energy consumption by producing a methodology of calculation of the integrated energy performance of buildings as well as proposing cost effective measures to lower each building?s energy consumption. As the measures should not contravene nor be incompatible with the intended quality and character of the building, the ?Energimerkeforskriften? exempts buildings that due to their historical and cultural values are protected cultural heritage legislation. The current system offers a couple of professional certification alternatives, but when two online semi-automatic methods developed specifically for non-professionals are by far the most used, and since the methods of calculation primarily have focused on modern building materials and construction, the rest of the historical building stock stands literally unprotected by incorrect performance certificates and high-risk energy efficient measures. The objective of this thesis is to identify if the current Norwegian energy certificate system poses a threat to older buildings.