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385 Uppsatser om Diversified forestry - Sida 20 av 26

Heterogenitet i skogsbestånd : faktorer av betydelse för artrikedom och förekomst av småfåglar

Denna studie undersökte hur heterogenitet i skogsbestånd samt omgivningsfaktorerna träddiameter, variation i träddiameter, död ved och lövinslag påverkar förekomsten av 18 skogsfågelarter i södra Sverige. Fågelinventeringen utfördes med hjälp av linjetaxering längs 100 meter långa transekter. Omgivningsfaktorerna mättes i varje transekt i fem provcirklar med diametern 10 meter. Analysen av träddiameter visade att det främst var diameter på barrträd, men inte på lövträd som inverkade på förekomsten av fåglarna. Sambanden mellan diameter på barrträd och totalt antal fågelarter var övervägande negativa vid 0-30 centimeter i diameter och övervägande positiva vid 30-80 centimeter i diameter.

Ersättningsmodeller för ballasttransporter : vid anläggning och underhåll av skogsbilvägar

Construction and maintenance of forest truck roads are a necessary element of industrial forestry. Payment for contracting services in this context can be done according to a number of payment models. This study will focus on the methods and consequences associated with a change of Holmen Skog?s payment model from per hour to per metric ton for ballast hauling. The aim of this study is to improve the economic efficiency of Holmen Skog?s ballast hauling in construction and maintenance of forest truck roads. This is done by formulating and evaluating a proposal for a payment model based on crowns per ton.

Comparison of bird communities in stands of introduced lodgepole pine and native Scots pine in Sweden

The introduced lodgepole pine (Pinus contorta) occupies more than 650 000 hectares in Sweden. There are some differences between lodgepole pine and Scots pine (Pinus sylvestris) forests which could affect bird assemblages, for example differences in canopy density and ground vegetation. Birds were surveyed in 14 localities in northern Sweden, each characterized by one middle-aged stand of lodgepole pine next to a stand of Scots pine. The two paired stands in each locality were planted by the forestry company SCA at the same time and in similar environment to evaluate the potential of lodgepole pine in Sweden. In those 14 localities, one to three point count stations were established in both the lodgepole pine and the Scots pine stand, depending on the size of the area.

Förröjning i förstagalling - vad kostar det och följer utförarna instruktionerna?

This report is a B.Sc. Forestry thesis work at the school for Forest Management, SLU. The work was an assignment from the forest owners? association Mellanskog. The aim of the work where to investigate the economical result of removing undergrowth trees before first thinning, and a follow-up of the contractors and their compliance with Mellanskog standards. This thesis work was divided in three parts: The first was to find a relation between the net volume from the first thinning and the cost of cleaning undergrowth trees. Secondly there was a follow-up in the field, to investigate whether the contractors have done the undergrowth cleaning according to Mellanskog?s directives.

Stormskador i lärk och gran : en jämförelse efter stormen Gudrun

The storm Gudrun January 8-9 2005 felled about 70 millions cubic metres forest in southern Sweden. The majority of the wind damaged forest was spruce (Picea abies). In order to decrease the risk of wind damages in the future other trees species are of interest for forestry in southern Sweden. The purpose of this master thesis was to study if larch were more wind tolerant than spruce. The method was to compare larch, Japanese larch (Larix kaempferi Lamb.), European larch (L.

Rekreationsanpassade skogsskötselplaner för friluftsområdena Mellsta och Skräddarbacken i Borlänge :

This Master thesis is performed at the request of the forest company Mellanskog and the local municipality of Borlänge in Sweden and aims to establish recreational adjusted forest management plan for the areas of Mellsta and Skräddarbacken in Borlänge. In all types of urban forestry it is very important that the management plan are accepted by the general public. To make sure that also these plans of future measures, pass in the public, interview studies have been performed in which the public wishes and interests have been examined and applied in the management plan. To make sure that future measures in the forest may be accepted by the public when the forest harvester enters the woods, it is very important that a well functional work of information has been made. The people living close by the forest shall have been informed a couple of weeks before the time of measures and it must also be good information available that explains what is to be done and why.

Zonerat skogsbruk på fastighetsnivå ? effekter på ekonomi och miljö

Det traditionella svenska skogsbruket bygger på ett trakthyggesbruk som tillämpas på största delen av arealen. Generell hänsyn lämnas vid skogliga åtgärder i form av levande och döda träd samt orörda områden. Utöver detta lämnas hela bestånd och nyckelbiotoper. Denna modell har fått kritik för att den skapar ett fragmenterat och variationsfattigt landskap med dåliga förutsättningar för många skogslevande arter att reproducera och sprida sig. Ett alternativ är triadskogsbruk där arealen delas upp i zoner med olika mål.

Att bygga en stamdatabas för gotländsk tall

Today's Swedish large-scale forestry uses almost exclusively computer-aided bucking. It allows the harvester computer, using an optimisation price list (steering price list), to maximize the value of each tree. The optimisation price list can be adjusted so that the industry gets the raw material it demands from the forest. There are various simulation programs that can be used when constructing a optimisation price list. The simulation program merchandise a database of stem shapes using a given price list and mimics a harvester's work. To get the demanded raw material for the industry it is important to use a well-adjusted optimisation price list.

Inclusive business and shared values : case study of Stora Enso in Lao PDR

Businesses role in society is changing. Corporations are expected to take responsibility, not only for their traditional business conduct, but also for social and political issues. A rise in globalization and international trade has led to an increased interest in the concept of CSR. Accordingly, stakeholders are expecting multinational companies to be accountable for existing issues in developing countries. New business models are needed to meet increased expectations of responsibility and shared value creation. Based on an understanding of the need for new business models a multinational corporation is studied in a local context, where a radically new way of doing business is developed.

Publicering inom skogsvetenskap : Bibliometrisk analys av ämnesområdet skogsvetenskap

Målet med denna uppsats var att göra en bibliometrisk undersökning av forskningsområdet skogsvetenskap, närmare bestämt publiceringen inom denna. Jag valde att göra en bibliometrisk undersökning inte bara på grund av att jag tycker att det är intressant och jag ville lära mig mer om hur man går tillväga rent praktiskt utan också för att jag tror att det är en viktig kompetens för framtida biblioteksarbete. Ett sådant kunnande kanske främst är viktig om man vill jobba i ett universitets/forskningsbibliotek men även på folkbibliotek görs ibland mindre bibliometriska undersökningar. Även på företag med egna bibliotek eller informationscenter kan kunnande om bibliometriska metoder vara en viktig kompetens. Undersökningen gjordes genom analyser av material hämtat från Web of Science. Datan jag laddade ner var artiklar publicerade mellan åren 2007 och 2010 och som fanns i Web of Sciencekategorin forestry.

Gröna upplevelser för alla : en trädgård för habilitering och återhämtning

Jällaskolans upper secondary School is situated on a big farm just outside Uppsala. The School is focused on agriculture, forestry, gardening, animal care and science. Jällaskolans staff has whished for a school garden for educational purpose where students can practice their gardening skills and learn more about plants. But most important, a specially adapted outside environment such as a garden, would be a great advantage for the students with special needs. This garden could even be an asset for other visiting school classes in the region.

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.

Jordlöparfaunan i bestånd av contortatall (Pinus contorta) och svensk tall (P. sylvestris) 1987 och 2010

In the 1970´s the North American lodgepole pine (Pinus contorta) was introduced to Sweden in large scale. The lodgepole pine affects its new environment different from Scots pine (P. sylvestris), leading to a change in biological diversity. Forestry today affects the ground beetle fauna (Carabidae). Habitat specialists associated with older forests are first affected. When the canopy closes again after a clear-cutting species that prefer open habitats reduces and those who prefer mature/closed forests increase. In this study we compare differences in diversity and community structure of ground beetles in stands of lodgepole pine and Scots pine.

Utveckling av en dynamisk Simuleringsmodell av en skotare

The predominant forestry harvesting method is based on the harvester-forwarder method, theharvester folds, branches and cuts trees, and sorts the logs into piles, while a forwarder transportsthe logs to a landing area.This master thesis work is about realization of a dynamic forwarder simulation model, and itspurpose is to provide an integrated forwarder simulation model in MATLAB/SimMechanicswhere the forwarder is based on a concept using pendulum arms to connect wheels and chassis.Active suspension control is developed and implemented into the simulation model, and finallycompared in simulation with passive suspension.In a first step, an integrated forwarder simulation model is developed, containing a simplifiedforwarder model, a tire-to-ground interaction model and a test track model. The simplifiedforwarder model is based a rigid multi-body system with a spring-damper suspension of thependulum arms. The tire-to-ground interaction model calculates the reaction forces, friction fromthe ground and applies the propulsion force. The test track model is a simplified version of thereal test track in Skogforsk. The propulsion wheel torque control is used to regulate theforwarder speed.

Förändringar i vegetationens sammansättning efter en våtmarksrestaurering : Changes in the vegetation composition after a wetlandrestoration

The loss of such great wetlands, which has arose in Sweden the last decades, has created a situation that threats both the function and the biological diversity within the wetlands. Many ecological niches can be found in the wetlands and it is one of the habitats where most different species exist. In the 17th Century people started to ditch damp environments, such as bogs, to create a productive cultivated ground. Further ditches were made when the forestry gave large economical profits. The wetlands were impoverished from both groundwater and nourishment, and this led to a great loss of species.In a corporation with WWF and Skogsstyrelsen in Arvika, the University of Karlstad has participated in the Laskerudproject, a hydrological restoration-project in a forest landscape.

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