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370 Uppsatser om Hollow trees - Sida 24 av 25

Landskapsplanering och konnektivitetsförbättringar inom värdetrakter i Västerbottens län :

According to the Swedish strategy for forest protection, additionally 40 000 ha productive forestland will be protected in the county of Västerbotten, between 1999 and 2010. A national project was carried out to distinguish the proportion of forest with a high biological value, in all counties. The project resulted in demarcation of small landscape areas or small ?biological value regions? (bvr), with higher concentrations of forests with conservation values and red listed species than the surroundings. In Västerbotten, 26 such bvr?s were identified and the Counties Agency and Forest Agency in Västerbotten developed a regional strategy for forest conservation to standardize the forest protection process.

Environmental variables determining the occurrence of Cladonia parasitica and Hertelidea botryosa, two boreal lichens confined to wood

Biodiversity is essential for human well-being and it is defined as the genetic variation within species and the variety of species and ecosystems. Biodiversity provides several ecosystem services which are necessary for human beings but there are different threats towards the biodiversity. The biodiversity linked to the forest in Sweden are threatened, about 50 % of the red-listed species in Sweden are associated with forests. This is linked to the commercial exploitation of the boreal forest in Sweden which started 200 years ago. The forestry the last 50 years, with clear-cuts, have contributed to a fragmented forest landscape.

Alternativa skogsbruksmetoder i Norden : ett välbehövligt komplement?

Clearcutting systems have been the dominating silvicultural approach during the last decades in the Nordic countries. While economically rational, it is also leading to a trivialisation of the flora and fauna, and may result in negative reactions of people in urban settings. As a consequence of this, and a more diversified view on which goods and services forests should deliver, there is an increasing interest in broadening the range of silvicultural methods that are used. The term continuous cover forestry (CCF) represents a suite of methods that have gained increasing interest in the Nordic countries. In CCF a considerable amount of the trees are left after harvest to favour values that require a continuity of tree-covered areas. There are thus hopes that this method will meet the needs for maintaining biodiversity and satisfy social and cultural values.

Rekreation och utomhuspedagogik i tätortsnära skog : planering av skolskog och rekreationsanalys för Sätra, en stadsdel i Gävle

This Masters Thesis includes a survey of recreational habits and the attitudes towards forests of the people of Sätra, a suburb of the city of Gävle. The study also includes the planning and design of a forest suited for education in the same part of the city. The thesis is a part of a project called Tätortsnära skog, commissioned by the Swedish forest agency. The project aims to survey the recreational habits of the general public in the regions of Dalarna and Gävleborg. Tätortsnära skog is focused on cities with a population of more than 20 000 inhabitants, of which Gävle, Sandviken, Falun and Borlänge all fall within the category.

Hur kan mångfalden gynnas på SCA:s naturvårdsareal? : natur- och kulturvärden i Peltovaara mångfaldspark

Områden med skyddad skog i norra Fennoskandia, som tidigare beskrivits som orörd urskog, har på senare tid visat sig vara påverkade av långvarigt mänskligt resursutnyttjande. Historiska analyser av ekosystem, där även antropogena störningar beaktas, har därför börjat lyftas fram som en viktig del i naturvårdsarbete (Foster m.fl. 2003). De hjälper oss att förstå hur strukturer och störningsdynamik har förändrats över tiden, vilket kan vara till stor hjälp vid skötselplanering och restaurering. Det övergripande syftet med den här studien var att kvantifiera kulturspår och analysera förekomsterna av kulturvärden i relation till framförallt naturvärden, men även sociala värden, i ett skyddsvärt borealt barrskogsområde. Min avsikt var att försöka exemplifiera hur skogshistoria kan användas för att skapa underlag för skötselplanering i områden med naturvårdsanpassad skogsskötsel.

Commercial thinning and its potential for contribution to the timber supply in British Columbia?s Interior forests : a look at Finnish and Swedish forest practices and their applicability in British Columbia?s Interior forests

Thinning is the partial removal of trees in a forest stand prior to final harvest. The term can be divided in pre-commercial thinning where little if any volume is removed from the stand and commercial thinning where removals are intended to provide a positive economic result. From a silvicultural point of view, the goal of thinning is to enhance future crop tree quality by removing low-quality stems and providing sufficient space for the accelerated development of retained ones (Huuskonen & Hynynen, 2006). The goals of this study was to see if commercial thinning could positively affect the short and medium term timber supply (MTTS) in the Interior regions of British Columbia (BC), and whether or not Scandinavian forestry practices could be adopted in the BC context. The mountain pine beetle (Dendroctonus ponderosae Hopkins) has created significant forest planning problems in BC. The annual allowable cut (AAC) was raised to capture beetle-killed timber while still merchantable.

Förutsättningar för återintroduktion av stora gräsätare i Sverige

Biodiversity is under threat in Sweden and many species are on the brink of extinction. This is mainly due to the large-scale drainage projects during the 19th and 20th century and the increasingly intensive land use in agriculture and forestry. The intensive land use with sharply defined boundaries between the production units has in many cases led to either overgrazing or overgrowing. As a result many species have been pushed back to "leftover" habitats like shooting ranges, power line corridors, roadsides, dumps, embankments and other similar areas. Therefore the question has been raised, wether or not it is needed to re-introduce large herbivores into the wild in order to maintain the biodiversity that is related to the extensive land use.This study has been conducted as a literature review and will focus on the European bison?s (Bison bonasus) impact on other species and biodiversity; conditions for reintroducing large herbivores in Sweden are also discussed.Free roaming populations of large herbivores have a positive impact on plants, insects and many other groups of organisms.

Lövskogsmålen i FSC-certifierat skogsbruk : tolkning, uppföljning och skötseldirektiv

Den mest eftertraktade råvaran i svenska skogar är barrvirke och detta har sedan länge varit vägledande för skogsbrukets planering och skötsel. Brandskydd, ökat betestryck och skötsel för barrträd har missgynnat lövträden. Eftersom lövskogar i den boreala zonen tillhör ett av de artrikaste ekosystem är kontinuerlig förekomst av lövträd och lövdominerade bestånd viktigt för den biologiska mångfalden. Den standard skogsägare certifierade enligt FSC (Forest Stewardship Council) har att följa innehåller två lövindikatorer, 6.3.8. och 6.3.9..

Ruttdetektering av tågtrafik

This master thesis investigates the possibilities of using GPS-information from trains to create a model of a railway system, register the routes of the the trains and predict how the trains will travel in the railway system.The thesis work was done at Icomera AB which is a company that specializes in internet connected vehicle solutions.We describe how the GPS-information is sent from the trains in the form of samples and investigate limitations and possibilities with the available information. About three million samples from 83 SJ-trains were analysed and the samples were filtered with the intent of removing erroneous information. We here found that about 30 % of the samples from the trains were unreliable.A solution for how the samples from the trains can be used to create a model of the railway system traveled by the trains is presented. We use a large set of historical samples and use cluster nodes and Hermite curves to generate a graph that represent the railway system with stations, nodes and the railway itself. A fully automatic solution is not presented since it did not fit into the time frame of the thesis; instead we created a simple tool which can be used to manually finish the model of the railway system.Furthermore, we describe how the railway system and the samples from the train can be used to register the routes the trains travel.

Vad påverkar skogsägarnas naturhänsyn vid föryngringsavverkning i region Mellannorrland? :

The objective of this thesis was to investigate what influence nature conservation measures taken at regeneration felling. Factors analysed were the forest owners´ situation and their characters, and information activities from wood-suppliers and the Regional Forest Board (RFB). The inventory was performed with a posted questionnaire followed up by telephone to forest owners and a posted questionnaire to wood-buyers. The forest owners were grouped in three strata, depending on the quality results (D- polytax inventory) of the taken forest conservation measures, and for this investigation forest owners were sampled from the population in the tree groups. In total 73 % (41/56) of the sampled forest owners answered the questionnaire Group A (17 answers): Good judgement Group B (19 answers): Bad judgement Group C (5 answers): This group was formed from the forest owners that were informed, by RFB, about nature conservation measures and culture history consideration before the regeneration cutting.

Utredning av möjlighet att automatisera trucktrafik

This master thesis investigates the possibilities of using GPS-information from trains to create a model of a railway system, register the routes of the the trains and predict how the trains will travel in the railway system.The thesis work was done at Icomera AB which is a company that specializes in internet connected vehicle solutions.We describe how the GPS-information is sent from the trains in the form of samples and investigate limitations and possibilities with the available information. About three million samples from 83 SJ-trains were analysed and the samples were filtered with the intent of removing erroneous information. We here found that about 30 % of the samples from the trains were unreliable.A solution for how the samples from the trains can be used to create a model of the railway system traveled by the trains is presented. We use a large set of historical samples and use cluster nodes and Hermite curves to generate a graph that represent the railway system with stations, nodes and the railway itself. A fully automatic solution is not presented since it did not fit into the time frame of the thesis; instead we created a simple tool which can be used to manually finish the model of the railway system.Furthermore, we describe how the railway system and the samples from the train can be used to register the routes the trains travel.

Distribution av sjukvårdens förbrukningsvaror en beskrivning av hur distributionssystemet kan förändras

This master thesis investigates the possibilities of using GPS-information from trains to create a model of a railway system, register the routes of the the trains and predict how the trains will travel in the railway system.The thesis work was done at Icomera AB which is a company that specializes in internet connected vehicle solutions.We describe how the GPS-information is sent from the trains in the form of samples and investigate limitations and possibilities with the available information. About three million samples from 83 SJ-trains were analysed and the samples were filtered with the intent of removing erroneous information. We here found that about 30 % of the samples from the trains were unreliable.A solution for how the samples from the trains can be used to create a model of the railway system traveled by the trains is presented. We use a large set of historical samples and use cluster nodes and Hermite curves to generate a graph that represent the railway system with stations, nodes and the railway itself. A fully automatic solution is not presented since it did not fit into the time frame of the thesis; instead we created a simple tool which can be used to manually finish the model of the railway system.Furthermore, we describe how the railway system and the samples from the train can be used to register the routes the trains travel.

Växelvis boende: Flexibla bostäder för "varannan vecka-familjen"

This master thesis investigates the possibilities of using GPS-information from trains to create a model of a railway system, register the routes of the the trains and predict how the trains will travel in the railway system.The thesis work was done at Icomera AB which is a company that specializes in internet connected vehicle solutions.We describe how the GPS-information is sent from the trains in the form of samples and investigate limitations and possibilities with the available information. About three million samples from 83 SJ-trains were analysed and the samples were filtered with the intent of removing erroneous information. We here found that about 30 % of the samples from the trains were unreliable.A solution for how the samples from the trains can be used to create a model of the railway system traveled by the trains is presented. We use a large set of historical samples and use cluster nodes and Hermite curves to generate a graph that represent the railway system with stations, nodes and the railway itself. A fully automatic solution is not presented since it did not fit into the time frame of the thesis; instead we created a simple tool which can be used to manually finish the model of the railway system.Furthermore, we describe how the railway system and the samples from the train can be used to register the routes the trains travel.

Effekter av gödsling i äldre tallbestånd på renbetesväxter i fält- och bottenskikt :

Reindeer husbandry and Forestry are both area related industries and will in big extent use the same lands. Conflicts often arise because of that the industries have different interests. Many of the activities done by the forestry influences the reindeer husbandry in an undesirable way, simultaneously as the reindeer husbandry activities can have negative consequences for the forestry. One such forestry activity is fertilization. It was during the 1960´s forest fertilization began to be practiced and the reason was that the increase in growth that the fertilization gave could be able to cover for the future shortage in wood many feared. During the 1970´s when the fertilizing activities were most intensive about 200 000 ha was fertilized annually.

Analys av trängsel på motorväg: Beräkningsmodeller för medelflöden/medelhastigheter samt utformning av påfartsreglering i Göteborg

This master thesis investigates the possibilities of using GPS-information from trains to create a model of a railway system, register the routes of the the trains and predict how the trains will travel in the railway system.The thesis work was done at Icomera AB which is a company that specializes in internet connected vehicle solutions.We describe how the GPS-information is sent from the trains in the form of samples and investigate limitations and possibilities with the available information. About three million samples from 83 SJ-trains were analysed and the samples were filtered with the intent of removing erroneous information. We here found that about 30 % of the samples from the trains were unreliable.A solution for how the samples from the trains can be used to create a model of the railway system traveled by the trains is presented. We use a large set of historical samples and use cluster nodes and Hermite curves to generate a graph that represent the railway system with stations, nodes and the railway itself. A fully automatic solution is not presented since it did not fit into the time frame of the thesis; instead we created a simple tool which can be used to manually finish the model of the railway system.Furthermore, we describe how the railway system and the samples from the train can be used to register the routes the trains travel.

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