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458 Uppsatser om Retention trees - Sida 30 av 31

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.

"Den kemiska bekämpningen av skadlig lövskog har öppnat helt nya vyer för skogsbruket" : flygbesprutning med herbicider i Arjeplog 1953-1978

Attityden gentemot lövträd och lövskog i norra Sverige började förändras i mitten av 1900-talet. Tidigare var lövträden en resurs inom det agrara samhället, men genom det industriella skogsbrukets utveckling började man alltmer betrakta lövträden som ett problem. Lövträden gav sämre lönsamhet på grund av att de inte efterfrågades inom industrin och lövträden ansågs även hota barrträden och deras föryngring genom sin förmåga att föröka sig vegetativt genom stubbskott och rotskott. Det fick till följd att det inom skogsbruket talades om ett ?lövproblem?.

Saltvattenuppträngning i Göta älv? Inverkan av förhöjd havsvattennivå på råvattenintaget vid Alelyckan

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.

Undersökning av självspridning av contortatallen i norra Sverige

Over the past 40 years 600 000 ha of lodgepole pine (Pinus contorta ssp. latifolia (Engelm.) Critchf.) has been planted in Sweden (280 000 ha on SCA's forest land alone which represents about 15% of the company's total forest land area). In the early 70's SCA situated a number of experimental stands in order to investigate different aspects of the exotic tree, primarily growth rate. To be able to compare the two species plots with scots pine (Pinus sylvestris L.), this species was also planted at the same time and under the same conditions. A number of questions should always be raised when exotic species are introduced in an ecosystem. Invasiveness, the pathogen situation and purely ethical issues should be discussed.

Spårtaxi i Eskilstuna : vägval och utformning i gaturummet

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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