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912 Uppsatser om Tree species - Sida 14 av 61
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.
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.
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.
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.
Effekt av brand och bete p? uppkomst av ?rtartade v?xter i restaurerade betesmarker. En j?mf?rande studie
Open ecosystems, such as grasslands and pastures, have naturally been shaped by disturbances like fire and grazing. These processes play a crucial role in creating habitats with high biological diversity, particularly favourable for a wide range of herbaceous plant species. In recent years, many of these disturbances have ceased, leading to encroachment, fragmentation and habitat loss. The aim of this study was to examine and compare the effects of fire, herbivory and a combination of fire and herbivory on the emergence of herbaceous plants. The study was conducted at the Ecopark at Nordens Ark.
Hypertrophic osteoarthropathy in wildlife : and a review of suggested pathogeneses
In this essay suggested pathogenesis of secondary hypertrophic osteoarthropathy (HOA) is reviewed. HOA, characterized by; periostitis, periosteal proliferation of tubular bones and arthritis can develop due to many different underlying diseases. The syndrome is most commonly seen with intra-thoracic malignancy or chronic pulmonary infections. HOA has previously mainly been described in humans and various domesticated species. More recently, through wildlife disease monitoring, cases have also been found among wild animals.
Störningsregimer vid Skövde övnings- och skjutfält : Stridsfordons påverkan på olika naturtyper i militära övningsområden
A lot of habitats have declined or disappeared as the old cultural landscape changed to the modern agricultural landscape of today. Places such as power line corridors, racing tracks, gravel pits and military training sites have become refuges for many species associated with the old cultural landscape. These sites have been exposed to ecological disturbances that create the same type of habitats that were found in the old cultural landscape.The military training sites in Sweden has an impressive diversity of species. Disturbances from the military exercises have created habitats that are important for a wide range of species.The purpose of this thesis is to study some of the ecological disturbances occurring in the military training sites of the Swedish Armed Forces and examine how they affect different types of habitats. The thesis explains through litterateur and field studies the reason to the rich biodiversity often found at military training sites.
Predation av sandräka (Crangon crangon) på juvenil piggvar (Psetta maxima) och juvenol skrubbskädda (Platichtys flesus) : betydelse av yngelstorlek för överlevnad hos piggvar och skrubbskädda efter bottenfällning
Turbot (Psetta maxima) and flounder (Platichthys flesus) are two species of flatfish both having their nursery areas around the shores of Gotland in the Baltic Sea. The common brown shrimp (Crangon crangon) is a known predator on newly settled plaice (Pleuronectes platessa) in the North Sea area and is also found in the Baltic Sea. Experiments were carried out to see if the brown shrimp is predating on juvenile turbot and flounder, and if so on which sizes, and if the brown shrimp prefers any of the flatfish species, and also to see if there is a difference between day and night in density of the shrimp, i.e. when the fish might be subjected to predation. The results showed that predation decreased with size for both turbot and flounder.
Mätning av träddelar och flis på Dåvamyran, Umeå energi :
The moisture content in 10 deliveries of tree parts and 10 deliveries of wood residues were measured with different methods to analyze the quality of procedure used at Dåvamyran today. At the same time a survey was made on the measure procedures used at heating plants in Sweden
The majority of the heating plants in Sweden use weight and moisture content as base for payment but at some plants only volume. The moisture content is usually estimated by drying wood chips in an oven but few plants a visual estimation is used. At few plants moisture content is estimated spectroscopicily. The techniques using near infra read light and other electromagnetic are still at a test stage.
The methods of measurement used today are quit unreliable for the individual deliveries and there is a risk for systematic mistakes.
Hur ska tall- och gran bestånd i Götaland gallras för att minska risken för vindskador?
With knowledge of how the southern Swedish forests have been affected by storms the past years, this study intended to find out which factors affect the storm firmness of a stand the most. The study was based on data from stands in the, by the storm Gudrun, affected area. The results of the analyses that tested the stand factors that influence the amount of storm damage to the greatest extent showed that the storm sensitivity of Norway spruce stands were largely due to previous management actions. The factors that could be controlled by thinning and had relevance of storm damage standpoint, according to the results were; the dominant height, volume, basal area weighted mean diameter and stand age at last thinning. In this study, these results are not as clear for Scots pine.
Inställning till och val av livsmedelsprodukter bland personer som är över 55 år
Data retrieved from airborne laser scanning represents a new source of forest data. Today, the technology has matured so that it can function in an operational environment. The aim of this study was to compile areas of application of laserdata in forestry. Moreover to analyze costs and accessibility of laserdata. The goal was to provide private forest owners information to support assessments of possible benefits of laserdata.
Rumslig fördelning av grov gammal tall i Uppsala stad med tallticka som indikator på höga naturvärden :
Fragmentation and reduction of forest area is a threat for many forest species and their habitat. Deficiencies in forest quality, such as lack of dead wood and old trees, are one explanation of the threat. The most important action to prevent the continued loss of forest types is to protect forest, but also to restore and to create areas that not previously had high nature values. Hence one of the key strategic roles for Fritid- och Naturkontoret, Uppsala municipality, is to monitor biodiversity in the context of urban planning.
The majority of the Uppsala municipality residents live in urban areas and most of them spend some of their spare time in natural areas in cities and their immediate surroundings. Exploitation in and around Uppsala is high, but it is important that there is enough nature close to houses to meet the residents? needs of recreation.
Ett träd och dess liv : Förskolebarns uppfattningar om träd
The aim of this study was to investigate preschool children's perceptions of trees in and it was done through qualitative interviews. The children were drawing trees and told me what the tree needs to grow and what happens to the leaves in autumn. In a playful way, they learned more about trees and the purpose was also to examine whether they had acquired new experiences and thoughts on the trees, photosynthesis and decomposition. Then the children were interviewed again to see if their answers were different. The results showed that the children gave different answers at the second interview.