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524 Uppsatser om Thinning stands - Sida 7 av 35

Beslutsunderlag för energianpassade gallringar i Västerbotten

The demand for renewable energy is increasing in Sweden. This consequently increases the pressure for and willingness to pay for forest fuels. One method to extract forest fuel from suitable commercial thinnings is the "long top method? (LT-method). With this method saw logs and non-delimbed tops are recovered, i.e.

Skogsvård hos privata skogsägare : vilka åtgärder utförs och av vem?

Many participants in the Swedish timber market procure raw material from private forest owners. They often also offer forest services to ensure reforestation after final felling. Selling silviculture services can be a part of creating a long term relationship with the landowner for future timber purchases. The Swedish Forest Agency monitors forest rejuvenation results in the entire country. In the latest survey (2006 - 2008) the proportion of approved regeneration area was 78%.

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.

Naturlig föryngring av lövskogar i Örebro län :

The Regional Forestry Board in Värmland- Örebro needs increased knowledge on silviculture in broad- leaved forests. This thesis is an inventory of naturally regenerated broad leaved forests, and the results from the inventory have been compared with The Regional Forestry Board?s demands on regeneration results. The result of this inventory was that the regenerated sites were suitable for broad leaved trees, but only half the number of the stands fulfilled the demands of regeneration results of The Regional Forestry Board, mainly because of gaps in the stands. The gaps in the stands were mainly caused by lack of soil preparation and seed trees..

Skogsskötsel för att minimera stormfällning över järnväg :

The society of today is dependent of secure transports and deliveries of electrical power. Interruptions in different activities because of fallen trees cost a great deal of money in form of reparations and claimed damages for transport companies and electrical suppliers. Fallen trees along some railway sections are a severe problem. For instance, to repair the damages of the storm of week 5 year 2002, costed 2 800 000 SEK for the line region of Hässleholm. Today, the Banverket railroad company has no norms in general for how close to the railway the forest is allowed to grow.

Productivity of Norway spruce (Picea abies) and Scots pine (Pinus sylvestris) in coastal areas of northern Sweden

Productivity of Norway spruce (Picea abies) and Scots pine (Pinus sylvestris) was studied on 12 sites in coastal areas of northern Sweden. On each site, sample plots were placed in adjacent Norway spruce and Scots pine stands with similar ages in between. Basal area, tree height, Site Index, volume production, simulated maximum mean annual increment (MAImax) and tree vitality were compared for the two species. Average basal area at the time of measurement was 30.4% larger for Scots pine stands than for Norway spruce stands. The difference between the two species in basal area increment during the last 10 years was related to stand age.

Vindfällning i naturliga och skapade bryn och kanter :

The aim of this work was to study if the edge of the forest is more resistant to heavy winds than the trees located further in from the edge, and how this edge effect changes between different types of tree species and site types. The data was collected from an electric power line going from the north to the south of Sweden. The mean value of the clearcutted area around the power line was 120 meters. The main direction of the storm in January 2005 was west-southwest and thus the power line was a perfect place for gathering a large data set. The main parameter studied was the damage frequency at the edge of the forest compared to the trees located further in from the edge (up to 100 m from the power line). Tree species mixture, soil moisture class, soil type, topography, stand height, stand height of the stand on the other side of the power line and wind exposition was estimated. The results showed a distinct edge effect. The edge of the forest had clearly lower damage frequency for all tree species. A marked difference was observed between tree species and damage frequency.

Identifiering av konfliktbestånd med hjälp av laserskanning

The interest in harvesting wood fuel in conflict stands has grown in recent years as a consequence of the increased demand for biofuel. Conflict stands are young forests that have not been cleaned and have a large number of stems ha-1with a great height and diameter distribution. This means that traditional field measurements in conflict stands are difficult and very time consuming. Therefore, the forestry sector is in need of new, more efficient inventory methods. In this study, the Lidar data from Lantmäteriet?s (the Swedish mapping, cadastral and land registration authorities) new national height model was used in combination with plots from the Swedish national forest inventory from 2009 to create functions for; height, volume, diameter and number of stems.

Skogsmarksgödsling : en ekonomisk analys av olika gödslingsstrategier för ett skogsinnehav i norra Sverige

The purpose of this study is to analyze the economic effects of different fertilization programs both on stand- and forest-level. The study is applied on an objective sample of inventory data for a forest area in Kalix in northern Sweden. The forest area belongs to the forest company Sveaskog. The study includes different economic models and will be used as a support when the company decides how to invest and how much to invest in fertilization. The study investigates the economy of five different fertilization policies. For each program the rate of interest invested in fertilization and the cost for the extra produced volume has been calculated.

Lövsuccessioner i sluttningar längs nedre Umeälven :

Secondary deciduous forests, which have their origin in earlier pasture- and meadow-land in slopes along the lower reaches of the Ume river, are thought to contain high nature conservation values, in spite of a relatively low age. The aim of this study was to clarify how factors as historical use, exposition, disturbance dynamics and successional age influences the conservation values in these types of riparian forests and how this can be implicated in the practical work with conservation and management at Umeå municipality. Sample plots were placed in seven stands with a variation of their historical use, exposition, disturbance dynamics and age of succession. Conservation values as structure, tree-regeneration, abundance and composition of vascular plants, amount of dead wood and the abundance of signal-species were measured and registered. The species composition and especially the composition of tree species, differed between forests with different exposition and different historical use.

Omfattningen av icke avverkade områdeni samband med slutavverkning :

This final thesis is performed on commission of Torsby forestry administration, Stora Enso Skog. Stora Enso Skog is one of the major forestry companies of Sweden. The main business area is located in and around the region of Bergslagen. During the last decade the practice of forest management has rapidly changed due to a new forest legislation. The new law has resulted in that the production goal is equal to the environmental goal within forestry.

Produktionsskillnader vid olika antal sortiment

This study is done together with Sydved AB in the summer of 2012. The purpose of the study is to analyse how different quantity of assortments influence the production for forwarders and harvesters with multiple tree handling aggregate in thinning, by different tree volumes. To make this analyse a time study was performed where three entrepreneurs work has been analysed. Beside the analyse, of different quantity of assortments, has also been analysed how the tree volume and a forest fuel assortment effect the production. The result of this study shows that the quantities of assortments have a significant meaning for the production. The biggest differences are most distinct between one and three assortments in the smaller tree volumes where production goes down if the quantity of assortments increase.

Skiktning och strukturell utveckling i unga naturlika skogsplanteringar: :

Multilayered woodland types are an important part of the urban forest. The knowledge how to establish and maintain such plantations are not as deep as other knowledge fields concerning forestry. Therefore this study has looked upon how to achieve multilayered structures in young nature-like woodland plantations. As a theoretical base for the study three different major knowledge culture have been studied that concerns the subject, ecology, forestry and landscape management/design. This three theoretical framework concludes that many natural processes strive in the opposite direction of multilayered structures in their youth.

Planteringsförbandets betydelse för kvalitetsegenskaper i Contortatall (Pinus contorta var. latifolia)

In Sweden, large scale planting of Lodgepole pine (Pinus contorta var. latifolia) started in the beginning of the 1970?s. At first, the aim was production of pulpwood, but later, also production of timber became considered realistic. Today, Sweden has more than 520 000 ha of Lodgepole pine.

Medlemsundersökning SÖDRA Skog

This report is prepared in cooperation with Södra, Norra Halland SBO. The survey gives the members an opportunity to influence the services and also gives the staff at Södra a hint of the member?s demands.Södra is the largest co-operative forest company in Sweden with over 50 000 members and is divided into 31 areas. Norra Halland SBO is one of them.A questionnaire was sent to the members and 516 (or 53 %) of them answered. Of the respondents 68 % were between 60 and 69 years of age.

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