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371 Uppsatser om Deciduous trees - Sida 16 av 25

Vegetationsutveckling och brandhistorik i Tyresta under 9000 år : en pollenanalytisk studie av en skvattramtallmyr i Tyresta nationalpark, Södermanland

Analyses of pollen and charcoal in peat cores, together with age-structure data of Pinus sylvestris from a Ledum-Pinus-mire in the Tyresta National Park (south-east Sweden) show the regional vegetation succession and fire history over the last 9000 years. Five major stages of mire development are identified: 1. Lake (c 7000-6400 cal BC); 2. Wet fen (c 6400-6000 cal BC); 3. Deciduous fen (c 6000 cal BC to c cal AD 700); 4.

Allanblackia stuhlmannii ? a tree under current domestication: what are the soil requirements?

Allanblackia is a genus of trees that grows in the rainforests of West, Central and Eastern Africa. Its big fruits contain seeds very rich in oil which has been used by local communities for cooking and making soaps. The native stands are threatened by overexploitation and the demand for the oil is much greater than the supply. Domestication programs, aiming at introducing the trees to small holder agroforestry systems, have been started for some of the species. The main aim of this study was to investigate the soil requirements of Allanblackia stuhlmannii in terms of chemical and physical parameters, as revealed by the soil conditions in native stands. Another aim was to see if these varied along an altitudinal transect.

Tallens fortsatta tillväxt i älgbetade bestånd

The Swedish Forestry Research Institute implemented an experiment which began in the year 1979 in a by moose browse damaged area in Sweden. An audit in 2014 of the moose browsing study called ?Furudalsförsöket? is the underlay to the study's results. By comparing Scots pine stands development in relation to known damage obtained thereby gives the understanding of how browsing affects the short and long terms impacts of Scots pines quality and volume production. The results of this year's audit reveal that the standing volumes in the undamaged and damaged areas represent a significant difference. The number and volume of the ingrown trees constitute a larger proportion of the areas that have been heavily browsed. It also proves once again that that all damage classes had a downward trend, which means that the damage is concealed with time.

Modeller för brösthöjdsålder för tall och gran :

The purpose of this study was to develop two types of prediction models for Scots Pine and Norway Spruce. The first type for calculation of the stump diameter under bark the year the tree reached breast height (Dstubh130). The second type for calculation of the annual difference, e.g. the number of growth years between stump height (0.2 m) and breast height (1.3 meters above ground level). The primary thought with these prediction models is to obtain the breast height age in the trees on basis of the number of annual rings at stump.

Uttag av energisortiment vid gallring av contorta, ett komplement till konventionell gallring? :

A recommendation for stand treatment of lodgepole pine (Pinus contorta) is, in a scientific point of view, lacking when it comes to harvesting for biomass energy. Within the next decades it is expected that 280 000 hectares of lodgepole pine will have reached thinning age on the domains of Svenska Cellulosa Aktiebolaget (SCA). Due to this the interest has grown rapidly for studying the possibilities of harvesting biofuel assortments already in the first thinning. In this study the distribution of the biomass within lodgepole pine trees has been studied and taken into account for estimating the proportions of harvested assortments when using different methods of thinning. The methods studied were conventional biofuel-harvesting (with delimbed branches gathered separately from the round wood) and thinning with cutting of round wood and long tops (incl.

Förändringen av tall- och granbestånden i eklandskapet söder om Linköping, 1927 jämfört med 2013

The aim of the study was to compare how the population of pine (Pinus sylvestris) and spruce (Picea abies) have changed between 1927 and 2013 in the oak landscape south of Linköping. A field study was carried out in 22 two kilometre lines which also had been studied in 1927. In these lines, which where ten meters broad and had a direction from west to east, the pines and spruces were counted, measured and classified by steam diameter. The obtained result was that the basal steam area (m²/ha) had increased for pine (44%) and spruce (57%) between 1927 and 2013. The amount of trees had increased in all diameter classes except thinner pine and spruce with a diameter of 5-10cm.

Älgens barkgnag på granstammar : omfattning med avseende på geografisk utbredning, skadad volym och ekonomiska konsekvenser

In three areas in the province of Småland studies has been done to investigate how big damage the moose may do to P. abies. An inquiry examination and two different types of surveys were done to find out how big area, which volume and which financial consequences the moose debarking has had on the forest. When the volume was calculated the rot spreading was included. The area that was damaged was stipulated with the answers from the inquiry examination. 59 % of the asked forest owners answered the inquiry.

Den sista vilan : vad kännetecknar en rofylld begravningsplats?

This essay examines the criteria for a peaceful cemetery. First there is a short history of the Swedish funeral place. After that follows the definitions of a peaceful place according to environmental psychology. From these definitions an analysis method is constructed for identifying a peaceful cemetery. The analysis method contains six criteria, shape of the entrances, existence of sound, vegetation character, the cemetery?s demarcation, the cemetery?s management and what feeling the cemetery mediates.The analysis method is put into practice on three cemeteries, Överklinten cemetery, Stockholm forest cemetery and the old cemetery in Malmö.

Lilaköttig taggsvamp, Sárcodon fuligíneovioláceus : miljökrav i Sverige och en analys av vad som styr artens etablering

Burnt Spine-cap Sárcodon fuligíneovioláceus are one the most endangered mycorrhizal fungal species in Europe. They have their main distribution in Sweden. It form mycorrhiza with pine and dependent on limestone, which makes it connected to a rare environment. It has therefore been important to study the ecology of it further and to recognise the requirement it has on the environment more accurate and what it need to establish in a new area. In this study, 31 of 34 known sites in Sweden was visited and studied in field and their history analysed through aerial photographs.

Dynamisk arbete med vegetation

Nybyggda parker och grönytor runtom i vårt land designas idag ofta utifrån ett slutgiltigt utseende. Med detta menas att en park som i slutändan förväntas domineras av tio stora ekar, planteras med tio ekar. Här finns det i stället en möjlighet att planera för förändring över tid, en långsiktig designprocess som tillåter andra uttryck att komma fram under vägen mot målbilden. Denna uppsats söker därför utforska hur vegetationsdesign och skötsel kan planeras så att de ger upplevelser kontinuerligt längs denna väg mot målbild. Tyngdvikten i denna uppsats kommer att ligga vid vegetationen under dess nyplanterade och unga år, då de fortfarande är plastiska och formbara. Naturlika planteringar, med Filborna Skogspark som exempel, kommer att undersökas.

Skötsel av tätortsnära skogliga rekreationsområden : besökares upplevelser i norra och södra Sverige

The main purpose of this M. Sc. thesis is to increase the knowledge about managing urban forestry for recreational use. The analysis is focusing on differences between visitors? experiences in the north and south of Sweden, represented by Nydalasjön and by Härlanda tjärn.

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.

Risk analysis and a study of risk awareness and risk communication at LEAF Gävle concerning dust explosions

The purpose of this report is to study the risk of dust explosions at the candy manufacturing plant Leaf Sverige in Gävle, Sweden. The risk analysis was conducted with a preliminary hazard analysis, PHA and event trees. The analysis focuses only on the risk posed to employees and material damages at the plant. No third person injuries have been considered. Another purpose of this report is to study risk awareness and risk communication concerning dust explosions.

Undersöka förbättringspotential med verktyg från Lean produktion

In the year 1783 a fissure eruption from Laki in the southern part of Iceland produced a large amount of volcanic gases during a period of eight months. The volcanic gases and aerosols spread across the northern hem sphere due to ideal weather conditions and had a substantial impact on the environment, human health and also climate effects. This, so called dry fog, caused severe health problems, which led to death casualties, killing animals, crops and other vegetation. The consequence was a widespread famine which was aggravated by a hard and long winter in 1783/84. Analysis shows that the Icelandic volcanoes are the primary risk to produce dry fog that can affect Sweden.

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.

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