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146 Uppsatser om Prescribed burning - Sida 1 av 10

Influence of prescribed burning and/or mechanical site preparation on stand stem density and growth of Scots pine stands above the Arctic Circle : results 9-19 years after stand establishment

Prescribed burning was commonly used for site preparation in Sweden to establish new forests until the 1960?s, when mechanical scarification was introduced. During recent decades the interest in Prescribed burnings has increased again, mainly due to certifications of forestry stating that 5% of the regeneration areas should be burned on dry and mesic soils. The objective of the study was to evaluate actual influence of Prescribed burning compared to other site preparation on stand stem density, growth parameters and tree damages for Scots pine (Pinus sylvestris L.) after direct seeding and planting. The study also attempts to simulate growth until first thinning.

Hyggesbränning på Orsa besparingsskog - en studie på tillväxt och föryngring,15år efter etablering

The main purpose with this study was to investigate whether the tree growth differs or not in prescribed burnt areas compared to mechanically scarified. Together with the result from the main purpose, answers of whether it's possible or not to combine nature conservation with tree production in prescribed burnt areas was presented. In these areas the regeneration were analyzed to see if there was enough tree plants to comply with the Swedish Forestry Act regulations terms for approved regeneration. A field survey was conducted at 6 objects, three objects for Prescribed burning and three for mechanically scarification. All objects were planted within the same year.

Clear-cut and substrate characteristics important for the occurrence of the beetle Upis ceramboides

Disturbances, such as fire and wind, are important for saproxylic beetles (= beetles depending on decaying wood) to gain substrate in boreal forests. Clear-cutting is an example of a man-made disturbance. Measures such as Prescribed burning have been made to resemble natural disturbances. The aim of this study was to see which clear-cut characteristics are important for the occurrence of the saproxylic beetle Upis ceramboides. This is a species favored by open habitats and is said to respond positively to forest fires. The distribution area in Sweden for this species has decreased during the last two centuries and I wanted to see if there were differences between clear-cuts in Hälsingland, where it is very rare and decreasing, and Norrbotten where this study was conducted.

Hur ofta bör småhus sotas? : En samhällsekonomisk analys av ändrade sotningsfrister

Sweden recently changed the national regulation of chimney sweeping. This study has two purposes. The first purpose is to evaluate the effect of this reform to see if the new regulation has led to an effect in terms of increased chimney fires in single-family houses and for the wood-burning and oil-burning stoves, respectively. The second purpose is an updating of a previous study (Mattsson 1994) of analysis of society´s benefits and costs of different alternative sweeping frequencies for wood-burning and oil-burning stoves. This study also has a secondary purpose to examine the extent to which the local sweeping rules vary with climate conditions.  Mattsson, based on his results, proposed that the sweeping requirements for oil-burning stoves should be reduced from twice a year to once every second year and for wood-burning stoves the sweeping should be reduced from four times to once each year.

Hur ofta skrivs anvädningsområde t på läkemedel inom ATC-rupp N04 (medel vid parkinsonism)?

Adherence to medical ordination is low and for long-time medication it is estimated to be as low as 50 percent. Depending on the prescribed drug this could lead to adverse effects and/or loss of effect of the drug. Information about why a drug is prescribed is important patient information and is thought to help increase compliance with the physician?s prescription. According to results from a recent study of visits to the emergency room at Karolinska Universitetssjukhuset in Solna, Stockholm, medically related problems were the cause in about 30 percent of the cases.

Mortalitet och skottskjutningsförmåga hos ek (Quercus robur) efter brand :

In this study I analysed how burning affects sprouting ability and survival of oak (Quercus robur) during the first season after a burn in southern Sweden. The study consisted of two separate field tests; in the first, two 300 m2- plots in western oak dominated forest were burned to analyze the fire behavior and the immediate mortality of oak and beech seedlings defined as individuals (> 20cm of height). At the end of the season almost 50% of the oak seedlings had resprouted while the beech seedlings had 100% mortality. An attempt to investigate the effect of the burn of artificially sown acorns was totally ruined by wild boar grouting before any conclusive results could be seen. In the second test the resprouting ability of oaks of varying diameters (average BHD 7-9 cm, range 2-42 cm) was examined one season after a prescribed burn in southeastern Sweden.

Environmental variables determining the occurrence of the red-listed Carbonicola anthracophila and C. myrmecina in boreal forests

The global biodiversity loss is mainly due to human activities such as an intensification of forestry. Boreal forest ecosystems in Fennoscandia are characterized by disturbances such as forest fires, storms and floods. However, industrial forestry practices suppress forest fires and change the landscape, leading to a loss of habitats and associated species. Particularly lichen species with slow adaptation abilities and a strong substrate specificity face an extinction debt in boreal forests since their substrates are long-lived but no longer created. In this study the species-substrate relationship of two red-listed forest-fire dependent lichen species Carbon-icola anthracophila and C.

Förbränning av pellets framställda av defibrerad granråvara :

Fuel pellets are in Sweden mainly produced from sawdust and cutter shavings. Before the pelletising process the raw material is dried to attain consistent moisture content and ground up in a hammer mill. In the densification process (pelletising) the ground material is forced through holes in a rotating die. This heats up the wood particles which cause them to soften and self bond. After the process the pellets are cooled, sieved and bagged. The milling process creates a wide range of particle sizes.

Återväxt av blåbär (Vaccinium myrtillus L.) efter ångbehandling : orsaker till effektiv kontroll

Steam was used as a site preparation method to eliminate unwanted bilberry (Vaccinium myrtillus L.) in the boreal forest. The efficiency of steam to suppress bilberry was compared with Prescribed burning and cutting the bilberry. Different combinations of steaming and/or cutting the bilberry were set up to investigate in which way steaming and cutting influenced the sprouting and regrowth of bilberry. The regrowth of the bilberry vegetation was monitored for 40 month. Steam was most efficient in suppressing bilberry.

Vad styr förekomsten av sälg och asp? : en studie av olika beståndstyper inom Hamra kronopark, Dalarna

Aspen (Populus tremula L.) and goat willow (Salix caprea L.) are two important tree species in the aspect of nature conservation. Due to the elimination of forest fires, a former negative attitude towards deciduous trees in forestry and a strong herbivore pressure, these tree species have been negatively affected during the last fifty years. The aim of this study was to investigate whether the occurrence of aspen and goat willow could be related to either human impact or to site properties, such as ground moisture and vegetation type. A side study included an inventory of a number of cyanobacterial tree lichens on aspen and goat willow in order to try to relate the occurrence of these lichens species to stand history and stand properties. The study was performed in Hamra State Forest in northern Dalarna. Nature reserves were compared with stands in managed areas.

Trädföryngring i låga gropar uppkomna vid brand i boreal naturskog :

This study was conducted in the "Kåtaberget" forest reserve in Västerbotten in the summer of 1999. In the summer of 1995, a Prescribed burning was performed in the reserve. In some places where coarse dry woody debris (logs and stumps) was present, the fire consumed the wood, as well as parts of the humus layer, creating deep-burned patches. The low intensity ground fire also created dead woody debris by burning off living trees with open fire scars, as well as standing dead trees. In this study, the post-fire tree seedling establishment was examined, with special attention given to the former presence of woody debris. The study also includes a survey of the areal extent of deep-burned patches, as well as an examination of tree seedling establishment in these patches, compared to other burnt ground.

Att restaurera forna tiders beståndsstruktur : ett exempel från Jämtgaveln

In Sweden today so-called "prescribed nature conservation burning" is performed due to the change in silvicultural law, certification and an increased knowledge regarding the field of fire in the forest landscape. The aim is to re-create structures and qualities made by the fire regimes of the past, though on a much smaller geographical scale. The structures and qualities to be re-created are for example broad leaf stands, trees with large diameter, heterogeneous stands regarding variables such as age and diameter. If we increase our knowledge of the constitution of forests characterized by fire, then we will be able to set goals for what achievements to reach both on landscape scale and stand scale. The aim of this paper is to try to describe how a stand from the past was composed regarding mainly the spatial arrangement and compare it with the stand of today in the same place. This to be done by using relict material, that is stumps and dead standing trees.

Att återställa en naturlig ordning : skogshistoria och restaureringsbränning i Långsidbergets naturreservat

During the late 1800s fire suppression became increasingly effective in northern Sweden which led to decreased areas of fire-disturbed woodland and successive changes in the structure of forests. In the long run this can pose a serious threat to fire-dependent and fire-favored species. Today some fire-prone forest reserves are burned as a nature conservation act. Often partial cuttings are made before burning, with somewhat different motives. The purpose of the study in Långsidberget nature reserve was to give a general picture of forest history and its affect on today?s forest condition, and to show how partial cuttings affect burning conditions and results. Långsidberget is located close to areas that were colonized during the Middle Ages.

Arbetsplatsförlagd utbildning - en verksamhet värd sitt namn? : -Om samverkan mellan skola och arbetsplats ur lärares och handledares perspektiv

AbstractIn the secondary-school program for hotel and restaurant complete courses or parts of courses are placed in workplaces so called workplace education (APU), this means that the content in the course plan must be discussed and be divided in a proper way between the school and the workplace, so that the students is gaining all the parts that is prescribed in the goals for the course.Interviews with tutors and teachers have been performed, with the purpose of investigating how the collaboration between the school and the workplaces should look like so that the APU fulfills the content and quality that are prescribed in the specifications of the education. The study shows that a better structure for collaboration between the school and the workplaces is needed. Lack of time and financial resources are the factors that according to the study reduces the possibility?s to (among other things) perform education of tutors, and for the teachers to plan and follow-up the APU-period..

Patienters följsamhet till läkemedelsordinationer- en litteraturstudie -

Background: One of the main concerns related to medical therapy is non-compliance to drugs. More than half of all patients do not comply with prescribed medication. Non-compliance to drug therapy leads to unnecessary suffering for the patient and there are no easy solutions to the problem. In order to create understanding for the individual patient it is important that medical staffs are enlightened on the existing problems concerning this matter. Purpose: To describe factors that effect compliance to drug prescription.

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