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170 Uppsatser om Spruce - Sida 3 av 12
Retention of stumps on wet ground at stump-harvest and its effects on saproxylic insects
Low stumps represent on their own up to 80% of the dead wood remaining on clear cuts and therefore supply suitable habitat for saproxylic insects i.e. insects depending on dead wood for their survival. Recent stump harvesting activities threaten this substrate of ecological importance and increase the anthropogenic negative impacts on these species. Because of technical and environmental reasons (nutrient leakage, erosion) guidelines for stump harvesting recommend to retain stumps standing in wet parts of clear cuts. However, stumps in wet positions might not be a satisfactory substrate for saproxylic insects and therefore might not be as much used as stumps in dry positions.
Utveckling av gran, Douglasgran, bok och tall under skärm av hybridlärk :
?Development of Norway Spruce, Douglas fir beech and Scots pine with a larch
shelter wood? is a report written by Per-Olof Magnusson. The thesis is a
compulsory part of forest engineer program at ?Skogsmästarskolan?, SLU,
Skinnskatteberg, Sweden.
The purpose of this report is to describe and evaluate an experiment with hybrid
larch (Larix x eurolepis) as shelter wood, and different tree species growth and
survival depending on the density of the shelter wood. The experiment is
conducted by southern Swedish forest research centre, faculty of forestry, SLU in
Alnarp.
The hybrid larch ought to be an interesting alternative to birch (Betula sp.) as
shelterwood on suitable sites in southern Sweden.
Marktillstånd och borbrist på åkermark planterad med gran i Västerbottens län :
This study was made on former agricultural areas that had been planted with Spruce or pine, in the county of Västerbotten. The goal of the project was to investigate suspected deficiency of boron in these areas. Several objects have been reported for possible deficiency and some of these have the characteristic symptoms of boron-deficiency. The hypotheses are that
1) Boron deficiency is present at several of the investigated objects.
2) Planting of forest on cultivated postglacial sediments leads to a successive podzolisation with a decreasing content of organic matter in the mineral soil, due to decomposition, and a decreasing pH in the soil, even on locations that have been added lime.
To be able to confirm or reject the hypotheses a number of tests were performed.
Inokulering med två hjorttryfflar på arginingödslade täckrotsplantor i Gideå plantskola :
The effect of inoculation on containerized pine and Spruce seedlings in a nursery with two
ectomycorrhizal fungi was investigated in regard to the development of mycorrhiza and plant growth. The fungi were Elaphomyces muricatus and Elaphomyces granulates and the inoculated seedlings were compared to an uninoculated control. These seedlings were all fertilized with arginine.
Five mycorrhiza species were found after DNA sequencing of the mycorrhizal root tips with different found morphotypes on seedlings from all treatments. Thelephora terrestris was the type which had the greatest distribution on pine seedlings and Tylospora asterophora was found at big extent on Spruce seedlings. The inoculated species was not found, if it was due to the species hadn?t colonized the roots or if the DNA sequencing failed we can only speculate about.
Produktivitet vid stubbskörd :
Stump harvest could be found in the late 1970?s and the early 1980?s. And now when the prices on energy are high it has become an interesting topic again. This work has been conducted within Holmen Skog?s stump harvest testing in Norrköping.
Ståndortsanpassning och produktionspotential för björk i Gävleborgs län
Large amounts of birch-timber are imported to Sweden, from particularly the Baltic States, since the domestic production can?t support the pulp industry. The goal of this study was to show the potential of birch and the area?s most suitable for birch production. The study was limited to Gävleborg County.
Using site characteristics, site index (SI) for birch was estimated on all National Forest Inventory plots in Gävleborg County.
Representera och konsumera landet : jag körde som en gran genom Sverige
This diploma work, with the title Represent and Consume the Land ?I drove following the picture of a Spruce through Sweden, is presented as a film and an essay and the aim is to explore the perception of an individual with the film as the medium. To reach this, it is necessary to destabilize my own reality, to explore myself at the same time as I study landscapes and representations of landscapes. The diploma work focus on representations of landscapes of Sweden, external pictures and internal images. The picture is a very strong medium that holds and comunicate myths, about the landscape and about the nation.
Poppel - en möjlighet i norra Sverige?
The countries in the European Union have agreed to increase their percentage renewable energy sources to 20 %. To reach this goal an increase of biomass production needs to be made. One way of achieving this is by using nonnative species.
Poplar in Sweden produces biomass faster than the domestic trees. In the southern parts of Sweden plantations has been made with good results. In the northern parts survival is a problem that needs to be solved before plantations can be made for commercial use.
Klibbalens gödslingseffekt på volymproduktionen i ett blandbestånd av gran och klibbal : en simulering i Heureka
A secondary and a pioneer tree species can with advantage be included in a mixed stand to increase the use of sunlight. Nitrogen-fixing plants have been shown to increase the supply of nitrogen in the soil by, for example, litter fall. This deposition acts as a biological fertilization, which may be used by non-fixing plants. Alder is a nitrogen-fixing, pioneer tree species that loses its nitrogen-rich leaves late in the autumn. The aim of this study was to examine the effect on the total volume of production, when different proportions of nitrogen-fixing Alder were part of Spruce stands.
Skottbetning på granplantor i Kolmården : omfattning och påverkande faktorer
In the Kolmården area, northeast of Norrköping in south-central Sweden, it was discovered that shoots of Spruce Picea abies, plants to a seemingly large extent had been browsed by deer. The area inhabits a dense red deer population, alongside with moose and roe deer, and red deer is thus suspected to cause the damage. The main purposes of this study are, however, to estimate the extent of the shoot-damage and to investigate what factors that may affect the browsing of shoots.
For each stand information was recorded about the age of the plants, area for the stand, height over the sea for the stand, site productivity, type of plants and stand-history.
The study was done in three areas: Simonstorp, Stavsjö and Valinge. At Simonstorp and Stavsjö, respectively, 10 stands were chosen for study and on Valinge six stands. In each stand, 10 plots were sampled.
Mätning av stamdiameter med markstående scanner :
Booth for operational planning of harvesting and for long term planning, data is today collected manually. Intensive objective field inventories are usually too expensive. To enhance optimisation of timber flow from forest to industry Moore efficient methods for measuring tree stems of standing trees are needed. The performance of terrestrial laser scanners have improved and these could possibly be used within forestry in the future. The objective of this study was to validate how a terrestrial laser scanner could be used to measure stem diameter, and to test how the errors depend on distance from the scanner and tree species.
Two plots (one pine and one Spruce) were used for this study.
Jämförelse mellan viltbehandlade och obehandlade granplantor : Med inriktning på höjdtillväxt och betesfrekvens
The report is a comparative study between Spruce plantations where 4 plants are treated with deer repellents and 4 plantations are untreated. The study aims to provide a base for the Forest Society's future decisions regarding the use of wildlife-repellents. The report indicates that wildlife-repellents work reasonably well for its purpose, the treated stocks were virtually untouched during the planting year and next year while the untreated stocks have been heavily grazed during these years. Growth difference between grazed plants and ungrazed plants found to be virtually non-existent (0, 01 m) of the treated stocks and 0, 07 m in the untreated plants. Because of the growth differences are so small between grazed and no grazed plants, it seems like the treatment of deer-repellent are unnecessary. Unless you know in particularly that the area has a specific problem whit severe deer-grazing..
Stormskador i stickvägsgallrade bestånd i sydvästra Sverige :
A storm in January 2005 felled 75 millions cubic metres of forest in South Sweden. Previous studies of wind damage in thinned stands indicated the importance of early thinnings. The risks of wind throw increased by increasing age and height of the stands. Previous studies also indicated increasing risk of wind throw along the strip roads. The aim of the present study was to investigate wind damage in Norway Spruce stands in South Sweden in relation to time of the first thinning and different pattern of strip roads (width, length and direction).
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.
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.