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227 Uppsatser om Scots pine. - Sida 6 av 16

Mekaniskt snytbaggeskydd

Insecticides will be removed from Swedish forestry, at present insecticides are used to treat our seedlings to avoid them from being attacked by pine weevils. With the forthcoming ban on insecticides alternative protective measures will have to be tested. Holmen Forest Ltd has aimed to find an alternative and have developed a mechanic pine weevils protection accessory as well as a new concept on planting pipes. Studies have been conducted on the behalf of Holmen Forest Ltd to see how planting with the newly developed mechanical protectors and plant pipe stands up against the conventional methods used today. The study was conducted over a three week period. Three factors were compared regarding planting quality including i) pressure around the plant, ii) the depth the plant ended up in, iii) plant angle. Mechanical plant pipes were used in the study, and where tested like a one-handed and a two-handed pipe. The study concludes that further development is needed for the mechanic plant protector to live up to the speed and quality of conventional methods.

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.

Konstens digitala upplevelserum: En upplevelseteoretisk fallstudie av två digitala besöksmål

Denna filosofie kandidatuppsats skrivs inom utbildningen Upplevelseproduktion vid Luleå tekniska universitet - Institutionen för konst, kommunikation och lärande. Syftet med studien är att undersöka vilken typ av upplevelser Tate samt The Museum of Modern Art (MoMA) erbjuder via deras webbplatser, samt att testa modellernas; Upplevelsefälten (Pine & Gilmore, 1999) och De tre generationerna (Boswijk et al., 2007), applicerbarhet på dessa två fall. Studien syftar till att besvara tre forskningsfrågor: ?Vilken generations upplevelse erbjuds via Tate respektive MoMAs webbplats??Vilken typ av upplevelser erbjuds via Tate respektive MoMAs webbplats utifrån modellen Upplevelsefälten (se figur 5)??Kan de två upplevelsemodellerna 4E - Upplevelsefälten (se figur 5) samt De tre genereationerna (se figur 6) tillämpas i en analys av dessa två webbplatser?För att besvara de tre forskningsfrågorna valdes en deduktiv ansats samt fallstudie som metodteori. De två fallen har analyserats utifrån två valda teorier; Upplevelsefälten (Pine & Gilmore, 1999) samt De tre generationerna (Boswijk et al., 2007).

Autumn water sources for understory vegetation and fungi in a boreal forest : an evaluation using stable isotopes

Understory vegetation and fungi are regarded as important ecological drivers of processes like productivity and nutrient cycling in boreal forests. Whilst those processes are linked to soil water content, relatively little is known about the sources of soil water for these forest components. During early autumn in boreal forests, temperature falls and large events of rain are frequent which may influence soil water availability. To better understand the autumn plant-soil-fungi water relationships in this ecosystem, I used stable isotopes techniques in this study to examine the water sources for ericaceous shrubs and fungi in a Scots pine forest following a large, early autumn rain event. I hypothesize that ericaceous shrubs of two functional groups (evergreen vs.

Insekter i hårt törskateangripna ungtallbestånd i Norrbotten : skadeinventering och artbestämning

Sedan i början av 2000-talet har nordligaste Sverige drabbats hårt av törskateangrepp och det är konstaterat att skadorna framförallt har orsakats av den värdväxlande varianten C. flaccidum. I Sverige visade forskning i början av 1900-talet att flera arter från fjärilssläktet Dioryctria (barrskogsmott) förekom i samband med törskateskador. Med de stora törskateskador som idag finns i norra Sverige är det fortsatt intressant att ta reda på vilka arter som idag kan påträffas och vilken roll de kan spela vid dessa skador. Syftet med studien har varit att, genom en fältstudie, bedöma förekomst och omfattning av angrepp från barrskogsmott och törskatesvamp i ett urval på 18 bestånd. Syftet var också att, med en kontrollgrupp genom en förkortad kläckningsprocess, försöka artbestämma barrskogsmotten som angripit träden samt att försöka bedöma hur vanligt det kan vara att insektsangrepp inte upptäcks i fält.

Uttag av energisortiment vid gallring av contorta, ett komplement till konventionell gallring? :

A recommendation for stand treatment of lodgepole pine (Pinus contorta) is, in a scientific point of view, lacking when it comes to harvesting for biomass energy. Within the next decades it is expected that 280 000 hectares of lodgepole pine will have reached thinning age on the domains of Svenska Cellulosa Aktiebolaget (SCA). Due to this the interest has grown rapidly for studying the possibilities of harvesting biofuel assortments already in the first thinning. In this study the distribution of the biomass within lodgepole pine trees has been studied and taken into account for estimating the proportions of harvested assortments when using different methods of thinning. The methods studied were conventional biofuel-harvesting (with delimbed branches gathered separately from the round wood) and thinning with cutting of round wood and long tops (incl.

Gallringsinventering från helikopter utrustad med profilerande laser och kamera för låghöjdsfotografering

Today Holmen Skog finds and selects suitable thinning stands using data on upper height and basal area. These figures are often based on basic forest data that has been updated with the help of growth prediction models. The problem is that these figures are not always correct. The aim of this study was to investigate if a combination of data from a profiling laser and a digital camera for low elevation photography, can be used for collecting data on number of stems per ha, tree species mixture as well as basal area weighted mean height and upper height for stands. The possibility to use these data to assess the need for thinning cutting was also investigated.Laser data and aerial photographs were collected from a helicopter operating at an approximate height of 100 meters.

Modeller för skattning av den vertikala fördelningen av biomassan på klena träd i röjningsgallringar

I samband med nya mål för energiförbrukningen har behovet av förnyelsebara energislag ökat. Ett sätt att möta detta ökade behov i Sverige är ett ökat uttag av skogsbränsle. Denna ökning skulle till stor del kunna bestå av ökat bränsleuttag i skog med hög stamtäthet och klena träd. För att på ett mer rationellt sätt kunna göra åtgärder i skog av detta slag är det av stor vikt att på förhand kunna uppskatta hur mycket man ska ta ut och hur mycket man ska lämna kvar som näring åt kvarvarande bestånd. Syftet med detta arbete var att skapa funktioner med vilka man ska kunna skatta biomassafördelningen i vertikal ledd för klena träd. Framtagandet av funktionerna har gjorts genom regressionsanalyser. Funktionerna bygger på data från Kristina Ulvcronas avhandling Effects of Silvicultural Treatments in Young Scots pine-dominated Stands on the Potential for Early Biofuel Harvests.

Biomassauttag vid delkvistat sortiment i klen gallring

The purpose of this study was to estimate the removal of biomass in connection with thinning operations in young stands that are dominated by small diameter trees. The economy of such operations depends on the products generated as well as the performance of the harvesting systems. Conversion tables designed to predict the outcome based on harvesting method was another goal of this study. Removal of biomass affects the nutrient composition of the site. Therefore it is a purpose that this study will provide researchers with some variables that can be utilized when studying this aspect. Trees were harvested and divided into bunches based on diameter.

Planteringsförbandets inverkan på bestånd av contortatall (Pinus contorta var. latifolia) med avseende på volymtillväxt och virkesegenskaper

At the beginning of the 1970´s forestry feared an imbalance in the future wood supply. Because of this anticipated "timber slump" forest companies undertook a variety of measures to counter this. One of these measures was the introduction of exotic tree species. The choice finally ended up with lodgepole pines which were considered a fast growing tree species compared to our native tree species. Theambition for the new lodgepole pine stands were to run these with rotation periods of between 40-60 years, thus smoothing out the ?timber slump? that was anticipated.

Det modiga Skottland : Skotsk nationell identitet och klanväsende

This thesis in social anthropology is based on the essence of Scottishness i.e. Scottish identity and Scottish clans. The thesis intends to raise the meaning of Scottish history for the Scottish identity and to analyse the relation between Scots and Englishmen. It is also meant to study how Geertz and Lewellen?s theories work in the Scottish field.

Produktivitet vid stubblyftning :

Stump wood was used between 1850 and 1950 for production of tar and as firewood. In the 1950s the use decreased because of the introduction of the cheap fossil oil. In the 1970s stump wood became an interesting issue again as a raw material for the pulp industry. Stump lifting has today become a possible source for bioenergy. The objectives with this study were to investigate the productivity of stump lifting and stump extraction, and to analyse the economy.

Vilken föryngringsmetod ger bäst resultat på torra och friska marker, höst- eller vårplanering? : en jämförande studie utförd på uppdrag av Stora Enso Skog

Regeneration with scarification and planting is a well known method, but the plants have a tuff period in the beginning. Decease of plants comes from pine weevils, dry weather, browsers, wrong method of scarification and wrong time for the planting. These are some courses why not every planting gets successful. The purpose with this study is to investigate witch time of planting gives the best result, spring or autumn planting and to give a answer of witch factors are the main course of deceases. The goal is to have the study to decide witch time to plant after final felling. The choices of plantings were maid from a period of three years. Spring plantings were from year 2005, 2006 and 2007 and autumn plantings were from 2004, 2005, and 2006.The purpose was to compare differences in deceases at the same spring weather.

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.

Föryngringsplan för en svårt stormskadad fastighet i Kronobergs län :

In January 2005 large forest areas in south Sweden were severely damaged by storm. This final thesis describes the work with creating an ecological and landscape-adapted regeneration plan for a severely storm damaged property in Kronobergs region in south Sweden. This regeneration plan, in difference to more regular plans, are focusing more on the owner?s use and goal?s for the property and seeing the property from a more comprehensive view in the regeneration process. Beside production and environmental values the plan also take in consideration other values as aesthetic, culture history, landscape picture and recreation values.

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