
Sökresultat:
132 Uppsatser om Thinning - Sida 8 av 9
Mortalitet av bok i Biskopstorp och Frodeparken naturreservat, Halland :
The aim with this study was to investigate mortality in older respectively younger beech
stands (Fagus sylvatica), the different types of dead wood in the forest and the availability of coarse woody debris (CWD). The research was carried out in previously managed and seminatural stands in Biskopstorp and Frodeparken, located north of Halinstad in Halland,Sweden. Data were collected from 22 stands with at least 50 % beech and with a minimum age of 5 1 years, ranging in size from 0,67 to 19,9 ha. A transect was placed in each stand, in which the diaineter on both dead and living trees with a minimum diameter of 50 mm was recorded. On seven to 13 dead trees, depending on the size of each stand, decomposition stage, primary and secondary cause of death, amount of fungi and the type of the dead wood was noted.
Effekter av höggallring i flerskiktad skog : beståndsutveckling i ett fältförsök med Naturkultur
Det övergripande syftet med denna studie var att jämföra volymtillväxten i skog skött enligt principen Naturkultur, genom olika starka höggallringar, med skog skött enligt traditionellt trakthyggesbruk. För att besvara frågeställningarna hur volymtillväxt och inväxning skiljer sig mellan de olika behandlingarna utfördes en fältinventering, under sommaren 2012, av ett försök anlagt 1990-91.
Försökslokalen var belägen i Åliden, 64ºN 20ºE, cirka 35 kilometer norr om Umeå. Försöket var anlagt i en sydvästsluttning 155 meter över havet och var tänkt att representera Västerbottens kustland. Försöket i Åliden ingick i en serie om tolv block med fyra behandlingar per block. Behandlingarna var dels två naturkulturbehandlingar där skog lämnats (Gles och Tät), en naturkulturbehandling där 90 procent av skogen avverkats och en behandling enligt traditionellt trakthyggesbruk (Kal och Kont).
Röjning på snö och röjning på barmark : effekter på produktivitet och kvarvarande bestånd
Approximately 4000-5000 hectares, of SCA´s forest land area in Västerbotten, are in need of pre-commercial Thinning (PCT) every year. Within the management district, the areas annually treated with PCT must increase, in order to decrease the area with an urgent need for PCT. This can be done by employing more forest workers or entrepreneurs, by mechanized PCT or by an extended season for PCT. Positive experiences from a private forest owner, who started to carry out PCT when the first snow came and then continued for several months, gave an idea to investigate the possibilities to prolong the season of PCT.
The purpose of this experiment was to compare PCT carried out when there was snow on the ground with PCT performed when there was no snow on the ground.
Kostnader vid gallring med flerträdshanterande aggregat, från skog till industri
Profit in first commercial Thinnings of today is hard to achieve. This is because of prevailing pulpwood prices and because of high costs of logging and transport. To reduce these costs higher productivity is advocated. One way to increase the productivity is the use of multi-tree handling harvester heads. The aim of this study was to calculate logging and transport costs in first Thinnings, where multi-tree handling has been used.
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.
Skiktning och strukturell utveckling i unga naturlika skogsplanteringar: :
Multilayered woodland types are an important part of the urban forest. The knowledge how to establish and maintain such plantations are not as deep as other knowledge fields concerning forestry. Therefore this study has looked upon how to achieve multilayered structures in young nature-like woodland plantations. As a theoretical base for the study three different major knowledge culture have been studied that concerns the subject, ecology, forestry and landscape management/design. This three theoretical framework concludes that many natural processes strive in the opposite direction of multilayered structures in their youth.
Planteringsförbandets betydelse för kvalitetsegenskaper i Contortatall (Pinus contorta var. latifolia)
In Sweden, large scale planting of Lodgepole pine (Pinus contorta var. latifolia) started in the beginning of the 1970?s. At first, the aim was production of pulpwood, but later, also production of timber became considered realistic. Today, Sweden has more than 520 000 ha of Lodgepole pine.
Kronandelsrelaskopering - metodoptimering och mätfelsstudie : metodoptimering och mätfelsstudie
I dagens skogsbruk bedöms gallringsbehovet utifrån gallringsmallar som ger rekommendationer baserade på avvägningar mellan biologisk kunskap, ekonomiska faktorer och risker. Gallringsmallarna är anpassade efter tänkta produktionsskogar och kan således vara bristfälliga i andra fall. Därför behövs en effektiv bedömningsmetod som fungerar i både homogena och heterogena bestånd. Studier har visat att tallens (Pinus sylvestris) grönkronandel har påvisad effekt på diametertillväxten och genom att uppskatta denna kan ett direkt mått ligga till grund för bedömning av gallringsbehov, istället för det indirekta måttet grundyta, som nuvarande gallringsmallar är utformade efter. Tanken är att undvika produktionsförluster genom att gallra innan grönkronan hissats upp alltför mycket.
Skogsskötsel för att minimera stormfällning över järnväg :
The society of today is dependent of secure transports and deliveries of electrical power. Interruptions in different activities because of fallen trees cost a great deal of money in form of reparations and claimed damages for transport companies and electrical suppliers. Fallen trees along some railway sections are a severe problem. For instance, to repair the damages of the storm of week 5 year 2002, costed 2 800 000 SEK for the line region of Hässleholm. Today, the Banverket railroad company has no norms in general for how close to the railway the forest is allowed to grow.
Strategisk och taktisk planering samt länken där emellan : analys av planeringsprocessens genomförande vid SCA Skog
To effectively manage a forest resource for both economic and other values good planning is required. The problem is complex since you want to know which forest to cut and when. Often a hierarchical planning structure is applied, including strategic (long-term), tactical, (medium-term) and operational level.
Today SCA Forest is one of few forestry companies in the northern Sweden with an integrated forest wood supply and industry. The goals of the company are to supply their own industries with wood and to manage the resources of the forest through a long-term perspective with satisfactory profitability.
Influence of prescribed burning and/or mechanical site preparation on stand stem density and growth of Scots pine stands above the Arctic Circle : results 9-19 years after stand establishment
Prescribed burning was commonly used for site preparation in Sweden to establish new forests until the 1960?s, when mechanical scarification was introduced. During recent decades the interest in prescribed burnings has increased again, mainly due to certifications of forestry stating that 5% of the regeneration areas should be burned on dry and mesic soils.
The objective of the study was to evaluate actual influence of prescribed burning compared to other site preparation on stand stem density, growth parameters and tree damages for Scots pine (Pinus sylvestris L.) after direct seeding and planting. The study also attempts to simulate growth until first Thinning.
Gallringsprioritering av contortabestånd :
Extensive planting of the tree species lodgepole pine (Pinus contorta var. latifolia) during the 1970s and 80s has resulted in large areas now being available for commercial Thinning. However, the varying quality of the stands creates a problem. The purpose of this study was to investigate, at the Torsby district of the Stora Enso forest company, how well the present computer records of the stands correspond to reality and determine which stands are, from a qualitative perspective, suited for timber production. Finding variables that indicate better stands would give Stora Enso the possibility of selecting qualitative stands which are more profitable to thin.
The study included 32 stands containing at least 70 % Pinus contorta.
Sveaskogs möjligheter att utveckla trädbränsleverksamheten i Västerbotten och södra Norrland :
This final thesis is initiated by the wood fuel department at the Swedish forest company Sveaskog as part of a project which also involves two other final thesises. The overall goal of the project is to investigate Sveaskog´s possibilities to produce and sell different wood fuel assortments in Västerbotten and the southern parts of Norrland. The aim of this thesis is to investigate how much wood fuel Sveaskog can produce in the area during the next five years and what that would cost. Furthermore the thesis will investigate the total possible supply of wood fuel from all other possible producers in the area. Treated assortments are forest residues from final fellings, whole trees from direct wood fuel Thinnings, non industrial wood and industrial by-products from sawmills.
The main effort to investigate Sveaskog´s production possibilities has been made to calculate the possible annual amount of forest residues and fuel from wood fuel Thinnings that can be produced.
Aspekter på flyttkostnader, fastighetsbildning och fastighetstorlekar :
This master thesis has three purposes. The first purpose is to give a theoretical background of how to divide up forest estates and to study how the legal system for these matters works.
A literature study has been carried out to give the background and a theoretical model has been made for analysing the law cases. The first purpose also partly touched the decision process in dividing up forest estates from point of view of the law of land parcelling (FBL), point of view.
The second purpose is to examine effects of a change of production requirements in 3 cap.7 § FBL as regards dividing up forest estates of private forest owners.
Effekter av låg grundyta efter första gallring utförd i praktiska bestånd
Varje år genomför Södra skogsägarna gallringsuppföljning av samtliga maskinlag som gallrar för Södra. En del av bestånden som blir uppföljda har en låg grundyta efter gallringen, utan att de har blivit gallrade hårt. Målen med rapporten var att undersöka om dessa bestånd har några särskilda egenskaper som gör att man kan identifiera dem före gallring och undvika att de blir för glesa samt studera effekterna av ett glest bestånd.
Totalt inventerades 19 granbestånd som blivit första gallrade och inventerade för fyra eller fem år sedan. Vid den tidigare inventeringen så hade tio bestånd låg grundyta och nio hade en normal grundyta efter gallringen. Vid inventeringen klavades samma träd i brösthöjd som vid det första tillfället, vidare mättes höjden på det grövsta trädet på provytan-.
Södra nyttjar simuleringsverktyget INGVAR för att skatta tillväxt och se gallringsbehov.