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3266 Uppsatser om National Forest Inventory - Sida 1 av 218

Hur stor areal äldre skog lämplig för trakthyggesbruk finns det på Gotland 2013?

The degree project at hand investigates how large areas of older forest (80 plus years) suitable for clear cutting there is on the Swedish island of Gotland. Large areas of older forest on Gotland are situated on land with shallow soil depths which are economically uninteresting and often unsuitable for clear cutting forestry. Other forests hold big nature conservation values and should not, or cannot, be used for forestry purposes. The survey is made as a GIS analysis based on the old but carefully made ?Brief forest inventory? (ÖSI) made in the 1980s and early 1990s. A sample from the inventory is combined with studies of orthophotos, satellite photos and other GIS layers that display estimated soil depth and nature conservation values. Partly contrary to common belief, the survey shows that there are still large areas of older forest suitable for clear cutting forestry on the island.

Privata markägares attityder och inställningar till föryngringsfrågor :

Even though Sweden is a small country which has a low rate of inhabitants is it one of the worlds leading nations of exporting products from the forest industries. The Importance of a sustainable use of the Swedish forests has been known for many years. In 1903 the first law of forestry were establish. Today the National Board of Forestry carry out inventories of regeneration result. The result of the latest inventory showed that especially the non-industrial private forest owners did not full fill the regeneration work after a clear cut.

Metod för inventering av underhållsbehov för skogsdiken

Large areas have been ditched in Sweden during the past 100 years to improve the forest production. Ditching and also maintenance of old ditches are operations having mainly negative effects on water quality, flora and fauna and changing characteristics of soil. The purpose of this study was to suggest a method for inventory of the need for ditching maintenance in old forest ditches that takes biodiversity, water protection and forest production into consideration. Inventory methods from five Swedish and Finnish forest companies, agencies and organisations were compared. Their employees were interviewed about their handling with ditches, forest production and nature conservation.

A Swedish national forest programme ? participation and international agreements

Sweden is in the initial phase of forming a national forest programme (nfp). The establishment of an nfp has been evoked by international policy developments and a national debate questioning Swedish forestry and forest policy. National forest programmes are participatory processes for the development and implementation of forest-related policies and international commitments. Hence, the aim of this master thesis is to assess the stakeholders? acceptance of participation and integration of international issues within the Swedish national forest programme.

Metod för kartläggning av lövråvara i Södra Skogs verksamhetsområde

Södra Skog chose in 2011 to convert the saw mill in Traryd to a gradually refined sawmill of hardwood. In 2009, they had also acquired the hardwood sawmill in Djursdala. This was strategically important for Södra's business since the demand for hardwood products has increased. The standing volume of deciduous trees in Sweden is today approximately 524 million m3sk and it has increased rapidly in recent years. However, the deciduous forests are to a large extent located in areas that are set aside for nature conservation and is thus not available to the industry.The goal of this work is to create a simple and reliable method for mapping of deciduous wood volumes in areas where Södra Skog is operating (Götaland excluding Gotland).The material that is used is raster databases with estimated forest attributes (kNN-Sweden), data from National Forest Inventory (NFI) and forest management plans.

En undersökning av Bergvik skogs och Skogsstyrelsens gallringsmallar mot en gallringsoptimering på simulerade typbestånd

The purpose of this study was to analyze the two thinning models: Bergvik Skog´s thinning model, which is based on total stems and dominant height, And Swedish forest agency´s thinning model which is based on basal area, habitat index, dominant height and recommended number of stems at final felling in Heureka´s StandWise and PlanWise. The data we chosen for our study were taken from the Swedish National Forest Inventory and we were creating a simulated stand based on a great number of sample plots in Region three from The Swedish National Forest Inventory. We had chosen to create one stand with low habitat index (T20) and one with high habitat index (T24). Our purpose were to come as close as possible to a natural stand in central Sweden. We performed the thinning in StandWise and analyzed the data I Excel files. Our thinning optimizing´s were performed and analyzed in PlanWise. There wasn´t any big differences between the thinning on the lower habitat index.

Skogsbränsleuttag vid förstagallring och dess påverkan på beståndsutveckling : simulering i Heureka med olika skötselprogram

Stands where pre commercial thinning has been ignored or inadequate often tend to have high stem density and low average diameter when they reach heights of thinning. In such stands, it can often be expensive to do a conventional pulpwood harvest as a first thinning. This study investigates the development of the stands and the economic outcome of forest fuel extraction, or a combined harvest as alternatives to the ordinary pulpwood harvest. Simulations in Heureka StandWise were performed for two thin and dense stands, which were constructed by data from the Swedish National Forest Inventory. The simulations show that the extraction of forest fuel in first thinning at an early stage can provide higher net revenue compared to conventional pulpwood harvest at the same time or later.

Lövskogens förändring i eklandskapet söder om Linköping : 1927 jämfört med 2013

The forests of Sweden are constantly changing. Map studies indicate that the amount of deciduous trees in Sweden has decreased in recent years in favor of the coniferous trees. The National Forest Inventory has since the early 1920s monitored the Swedish forests and in recent years has made the old data digitally available. In the present project, we have investigated how the numbers of stems in different diameter classes have changed for birch and other deciduous trees. The inventory was conducted in the same manner as in the first forest inventory.

Hållbart skogsbruk och naturvård ? ett skogsägarperspektiv

The Swedish government has set up 16 environmental goals for Sweden to achieve. One ofthem is ?Living forests?, which is the foundation for the ?National strategy for the formalprotection of forests?. The ?National strategy? puts the private forest owner at the centre ofattention in order to achieve the environmental goal ?Living forests?.

Vinster med björkinblandning i granbestånd i syfte att höja markens pH-värde

The soil acidification and the pH-value of the soil have been discussed for many years. Many observations of the tree species effects on the soil pH have been done. We have discussed the effects on the soil surface pH-value with a birch (Betula spp. L.) admixture in Norway spruce stands (Picea abies L.).We have used data from the Swedish National Forest Inventory. We have also discussed how the wood production and the biodiversity can be increased in mixed stands, in according to the Swedish forestry act Skogsvårdslagen. Our sampling areas are located in Norrland, Sweden. The results show a significant correlation between an increased birch admixture and an increased pH-value of the soil.

Utvärdering av digital flygbildstolkning & automatisk beståndsindelning för det praktiska skogsbruket :

To be able to plan different treatments, accurate data is required. The collection of data is often expensive and that?s why the aim is to lower the inventory costs without loosing the accuracy of the data. Holmen Skog has in its strive to lower the costs, decided to evaluate two different methods for forest delineation, computer aided forest delineation and digital stereo view. This study?s purpose is to evaluate these two methods in regard to usability for a beginner and how good the delineation gets.

Bokhögstubbar i Klåveröds strövområde : utbredning, egenskaper och betydelse för rödlistade vedlevande skalbaggar

Lack of dead wood is the main cause of decaying or loss of populations for many forest species. To increase the amount of dead wood is a prerequisite to maintain biodiversity in forests of northern Europe. In summer 2006 the recreation area Klåveröd, at Söderåsen in Skåne, Sweden, has been inventoried for high stumps (snags) of beech, (Fagus sylvatica). The result of the inventory has been compared with data of the real estate and forest management directories from the owner, region Skåne. The results have also been matched with the results from an inventory of saproxylic beetles in 2005, performed with windowtraps on selected snags both in the area and the adjacent national park Söderåsen. 594 snags were found on 747 ha.

Från gles skog och brokiga ungskogar till homogen produktionsskog : en skogshistorisk studie av Hällforsmarken under 1900-talet

The forest in the northern part of Sweden has changed dramatically during the last centuries. The forest has gone through a large-scale transformation, from it being only used locally for domestic purposes to becoming very important raw material for Sweden in the industrial age. The strategy by foresters during the second half of the 20th century has been to create pure production forests for commercial forestry. This has mainly succeeded and we have today homogenous production forests that give a high profit to the owners. The aim of the study is to compare the state of the forest in the former state forest Hällforsmarken in the years 1925 and 2000 and to interpret the changes which has taken place.

Identifiering av röjningsbestånd med hjälp av flygburen laserskanning

Bergvik Skog is one of the leading forest companies in Sweden who use airborne laser scanning for forestry information. They utilize laser data retrieved by the Swedish National Land Survey to describe the forest holdings and facilitate planning for thinning and final felling operations. However, the possibility to identify stands with clearing needs by using laser scanning data has not been tested in a large scale. The data used in the current study are field data from The Swedish National Forest Inventory in combination with laser data from the Swedish National Land Survey acquired in 2009. The collected data is used to find one or several laser variables that best describe the relationship of the field measured samples with clearing needs.

Människan i urskogen : vegetationshistoria i Hamra nationalpark under 2500 år

Pollen analysis of a peat core was used to reconstruct the last 2500 years of vegetation history, with focus on the impact of anthropogenic disturbance, in Hamra National Park, central Sweden. In addition, analysis of pollen in soil samples was performed in an attempt to locate ancient cultivation plots in the National Park. The analysis of the peat core shows a development of the vegetation that can be divided into four stages of different degrees of human impact: A - virgin forest (c. 500 B.C.-A.D. 1300), B - grazed forest (c. A.D.

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