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3373 Uppsatser om Fast growing tree species - Sida 18 av 225
Fältinstruktion för skogsbruksplanering av inhemska skogar i Andinska Patagonien :
The thesis first objective was to develop field instructions for forest planning of native forests in Andean Patagonia, and the second objective was to test the plan on an actual property in the area. The thesis was limited to studies in the province of Rio Negro. Today, there are no official forest management plans for native forests in the Argentinean province of Rio Negro; thus, there is an obvious need for an official forest management plan with clear guidelines. To be granted permission to manage, i.e. through thinning, the native forests on a property it is required to have a forest management plan that is approved by the Forestry Board in the province in question (Thill, B.
Biologin hos svenska Lilioceris arter och åtgärder för att begränsa deras skadeverkningar :
Summary
The leaf beetles, Lilioceris lilii and L. merdigera have existed in Asia, Europe and in North Africa for a long time, but have become much more abundant the last twenty-five years. Even North America has been affected during the last years.
The purpose of this investigation of Lilioceris species in Sweden, is to give advice to gardeners, which type of control measures is the most effective in order to restrict their damage to lilies.
Lilioceris species overwinter normally as pupae in the soil under the host or close by.
Literature and contact with advisors have described the life cycle and spreading of Lilioceris. Under favourable conditions these leaf beetles have two generations/year in the south of Sweden. Both the adults and the larva eat the foliage, and by strong attacks even flowers can be eaten and only the stem is remaining.
My own observations include different treatments of both lily foliage and of the leaf beetle.
Skogseldens påverkan på epifytiska trädlavar på tall i relation till brandintensiteten :
Not much is today known about how epiphytic lichens are effected by fire. A considerable part of the fires in Sweden today are prescribed fires for the purpose of environmental conservation. How these fires affect lichens is largely unknown. The aim of this study is to find out how epiphytic fruticose and foliose lichens on Scots pine are affected by fire, and to elucidate the relationship between fire intensity and the survival of lichens and later re-colonization.
The study was performed at three locations just outside Umeå in Västerbotten that were burned 5-7 years earlier. In all locations there were larger groups of surviving Scots pines with varying amount of fire-damage in the crown, which enabled a reconstruction of fire intensity.
Tillämpning av lättrörliga systemutvecklingsmetoder - en studie av systemutvecklingsprocessen i en ad hoc-krati
Due to fast growing and rapid changes in markets today, most of the organizationsthat are trying keep up with these changes have a high demand for software that areof high quality and comes with a low price. To meet these goals software companieshave to implement new methods to develop software that are suited for rapidchanges. The concept of agile methods can fulfill this need. Our purpose with thisthesis was to investigate how well agile methods could be applied in organizationsthat could be identified as adhocracies. A case study was conducted in anorganization which we could identify as an adhocracy.
Timmerkvalitet hos björk i blandskog med gran
Birch is the dominant deciduous tree species in Sweden but only 16 % is found in pure birch stands. The majority of the birch (51 %) is to be found in conifer dominated stands. Swedish forest land comprises approximately of 23 % mixed stands and one problem is that for mixed stands there are few management recommendations. The underlying aim of this thesis was to study the management of mixed forest stands of spruce and birch to achieve good timber quality of birch. The study was based on a literature study and measurement in a field experiment launched in 1998 by the Swedish University of Agricultural Sciences (SLU).
Virkesproduktionen under 80 år i ett fältförsök i Dalarna med olika skogsskötselsystem
I Sverige är trakthyggesbruk med kalhuggning det dominerande skötselsystemetmen intresset för kalhyggesfritt skogsbruk har ökat de senaste åren. Alternativentill kalavverkning är omdiskuterade och kritiseras ofta för att inte vara lönsamma.Målet med detta examensarbete är att analysera ett långtidsförsök med olikaskogsskötselsystem och att diskutera eventuella produktionsskillnader. De fem skötselåtgärdersom undersöktes var 1) kalavverkning med plantering av gran och tall,2) naturlig föryngring under fröträd, 3) blädningsbruk, 4) dimensionsavverkningoch 5) orörd skog (referensyta). Fältförsöket ligger på Siljansfors försökspark iDalarna och anlades 1923. Alla försöksytor har en areal av 1 ha.
GIS-modellering av habitat för vitryggig hackspett (Dendrocopos leucotos) som hjälpmedel i naturvårdsplanering på landskapsnivå :
The white-backed woodpecker is a forest bird being critically endangered in Sweden. The species is dependent on older forests rich in deciduous trees and dead wood. The main problem for the survival of this species is present shortage of habitat. Conservation work on this umbrella species is at present focused on finding remaining or emerging habitat networks. Large areas are scrutinized in search for suitable habitats to be protected or managed for the species sake.
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.
Rum och rörelse - analys av alléns betydelse för människa och landskap
Within literature, politics and science, there is a claim that ?tree avenues are important?. But the question and the goal for this essay are to explore the pretext to how and why. Planting tree avenues is a 4000 year old tradition and they are a common element in the Swedish and Scanian landscape since the 18th century. They were first mainly planted by aristocratic land-owners or on their initiative, but since the 19th century also by farmers.
Samverkan på svenska mötesdestinationer.
Not much is today known about how epiphytic lichens are effected by fire. A considerable part of the fires in Sweden today are prescribed fires for the purpose of environmental conservation. How these fires affect lichens is largely unknown. The aim of this study is to find out how epiphytic fruticose and foliose lichens on Scots pine are affected by fire, and to elucidate the relationship between fire intensity and the survival of lichens and later re-colonization.
The study was performed at three locations just outside Umeå in Västerbotten that were burned 5-7 years earlier. In all locations there were larger groups of surviving Scots pines with varying amount of fire-damage in the crown, which enabled a reconstruction of fire intensity.
6-9 åringars spontana uppfattningar om fast och flytande materia
Undersökningens syfte var att öka vår kunskap om hur elever, i åldern 6-9 år, spontant beskriver materieuppbyggnad i fast och flytande form samt vad som händer då fast materia löses i flytande materia. Detta för att vi som pedagoger skall kunna stödja elevers naturvetenskapliga begreppsutveckling. Vi använde oss av enskilda kvalitativa intervjuer för att få svar på våra frågeställningar. Eleverna fick beskriva hur materia i deras vardagsmiljö är uppbyggd och vad som händer när fast materia ska lösas i flytande materia. Deras svar var till 90 % av ett makroskopiskt, kontinuerligt perspektiv.
Vems landskap ska förändras för att öka den biologiska mångfalden? : En studie av skillnaderna i odlingslandskapets konnektivitet med avseende på två skyddsvärda arter med olika preferenser
Organisms relevant for nature conservation dont follow administrative borders. Because of this there is a need for a landscape perspective within conservation and planning, and a need for the species of interest to have legal protection. Network analysis adapted for ecological purposes has grown to become a powerful tool for studying and communicating the relationships between species dispersion and access to habitat. In this study the following question is posed: How is the Osmoderma eremita and the Pernis apivorus dispersal possibilities in the small scale cultivated landscape of Borås affected by exploitation in respect to a) dispersal ability, b) habitat quality, c) position of habitat patches in a network? The analysis were based on municipal and regional nature conservation data, which in due to confidentiality is not accounted for in the report by maps, coordinates, etc.
Prestationspåverkan av flerträdshantering i klena gallringar
The aim of this study is to investigate how multiple tree handling harvesters perform compared to earlier developed standards. The study shows that multiple tree handling harvesters are more efficient in thinnings stands with mean stock volumes less than 0,12 m3fub per stock. The increased efficiency is different for different mean stem classes. In stands with a mean stem volume of 0,04 m3fub per stock, the increase can be as high as 40 percent while it is about 10 percent in stands with a mean stem volume of 0,12 m3fub.
Comparisons have been done between stands that are felled with partly limbed stands and stands without partly limbed assortments. The difference in performance is clear and shows that the partly limbed assortments strengthen the multiple tree handling harvesters positive effects in low dimension thinnings.
Framtagning och analys av en arbetsmodell för kartläggning av användarbehov
This study began with a mission statement from the firm Tobii Technology AB to identify customer needs in the relatively new and rapidly growing market for eye tracking analysis. After consuling external experts, the authors however found that the availability of previous academic published market studies of new and fast growing markets was poor. Therefore a decision was made to execute the task and at the same time create a methadology for future studies in this area. The identification of customer needs, which formed the basis of the insights and analysis, led to frequent discussions between the authors and the firm's supervisors. This resulted in a project plan and a decision that an iterative model would be used, were earlier decisions would be questioned and refined throughout the project.
Diversitet hos jordlöpare (Col: Carabidae) i hävdade strandnära gräsmarker :
Diversity of ground beetles (Col: Carabidae) in managed riparian grasslands.
The carabid community in moist seminatural grasslands was studied at three different sites in mid-Sweden. Pitfall trapping was carried out during six weeks in spring and early summer 2003. Eight transects, each containing seven pitfall traps, were placed in three different management regimes, either late or continous grazing, or meadow.
The species composition was analysed by ordination analyses, i.e. DCA and CCA.