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524 Uppsatser om Thinning stands - Sida 11 av 35
Naturvårdsrestriktioners effekter på brukandet av ädellövskogen i Skåne :
Restrictions in nature conservations are increasing the influence of forest management. Nobel broadleaved forests are more influenced than other forests, because they are considered to be more valuable than other forest types in Skåne. There has been a lack of knowledge about the amount that is set-aside for nature conservation and what types of forest that is concerned.
These are the main questions to be answered in this thesis. Moreover has the timber quality been compared between set-aside and non-set-aside areas since it affect the financial conditions for the forestry in nobel broadleved forests. The last asked question deals with the financial consequences of set-aside.
Sällskapet örtagårdens vänners trädgård i Vadstena : aktuellt växtinnehåll i historisk belysning och med sikt framåt.
Dead wood is important for many species. The amount of coarse dead wood (diameter >10 cm) is much lower in managed forest than in unmanaged forests. Stumps constitute the largest proportion of the volume of coarse dead wood in managed forests. Since stump harvest for biofuel may increase, the amount of dead wood will decrease even more, which may threaten biodiversity. The first aim of this study was to compare the amounts of fine woody debris (FWD, .
Nyckelbiotoper - urskogsrester eller kulturprodukter? : beståndshistorik i tolv nyckelbiotoper i Lycksele kommun
Since 1993 the Swedish Forestry Administration conducts a nation-wide inventory of wood-land key habitats covering all forest land in Sweden. The inventory aims at mapping and describing habitats where redlisted species occur or can be expected to occur. According to the inventory stand history is crucial to the presence of red-listed species. However, the current knowledge of stand history in woodland key habitats is very limited.
The purpose of this work is to describe stand history in woodland key habitats, i.e. fire history, human activities - mainly cuttings - and structural changes.
Epixylic lichens and bryophytes in young managed forests : substrate preferences and amounts of dead wood
Dead wood is important for many species. The amount of coarse dead wood (diameter >10 cm) is much lower in managed forest than in unmanaged forests. Stumps constitute the largest proportion of the volume of coarse dead wood in managed forests. Since stump harvest for biofuel may increase, the amount of dead wood will decrease even more, which may threaten biodiversity. The first aim of this study was to compare the amounts of fine woody debris (FWD, .
Modellering av diametern hos tall (Pinus sylvestris) som en effekt av beståndstäthet och biomekanik
Med gallringseffekt menas att träden efter en gallring ökar sin diametertillväxt. Denna effekt har traditionellt tillskrivits den minskade konkurrensen om ljus och näringsämnen mellan träden. En alternativ förklaring till gallringeffekten är att vindpåverkan per träd blir högre i det gallrade beståndet, vilket leder till större svajningar för träden och därmed en ökad diametertillväxt.
I studien undersöktes ifall vindens påverkan är en del av gallringseffekten på tall (Pinus sylvestris L). Lokalen för studien var SLU:s försökspark i Siljansfors utanför Mora. Omgivande tätheter av stamantal, grundyta, kronvolym och kronmantelyta beräknades på flera avstånd från varje individuellt träd.
Prestation i traktplanering
This study was an assignment for the company Holmen which is located in the region of Örnsköldsvik, Sweden. The study was focusing on the responsibilities of a forestry planner during the planning season.
The study was investigating about how much time the planner spent in the office, in the car and out in the forest. Any other issues that would cause delays were also identified. To be more effective and to increase the number of objects to a district bank, a better preparation in the planning stage (for thinning?s or clear cuts) is needed as well as faster transition on to the next area.
Productivity of integrated harvesting of pulpwood and energy wood in first commercial thinnings
The aim of this study was to quantify the productivity and the costs of different harvesting systems (teams), containing harvesters equipped with accumulating harvester heads and forwarders, in first commercial thinnings were an integrated harvest of pulpwood and energy wood were performed. In the beginning the plan was to study and measure 20 sites before and after harvest. Due to storms during the summer of 2010, complete data could only be obtained from 8 of these 20 sites. Seven of these sites were privately owned and one was owned by UPM, all of the sites had been pre-commercially thinned. The mean stem density before harvest was 2578 stems per ha and the mean stem volume was 0.074 m3solid over bark.On average 1518 stems/ha was harvested.
Epixylic, forest-interior bryophytes in young stands : importance of local environmental variables, propagule sources, and distance to bordering woodland key habitats
The reduction of coarse, dead wood is considered to be the biggest threat to flora and faunain boreal forests. Extensive harvest of logging residues would increase this reduction evenmore. However, the role of dead wood created at final felling for boreal, epixylic species isstill largely unclear. It is therefore of interest to examine whether epixylic species inhabit thedead wood in young, boreal stands, especially species considered to be confined to forests inlate successional stages.The aim of this study was to investigate whether forest-interior species in fact can inhabitearly-successional forests arisen after logging. The study was conducted in young standsbordering dead wood rich woodland key habitats.
Val av tidpunkt för markberedning vid naturlig föryngring under skärm av Pinus sylvestris i Svealand : Timing of scarification when using natural regeneration in seed tree stands of Pinus sylvestris in Central Sweden
This thesis is built on a field study that was carried out in two seed-tree stands near by Götbrunna in Uppland, Sweden. The aim was to examine if scarification carried out in spring time could generate a more dense seedling establishment when using natural generation, than scarification carried out in autumn. It was also investigated whether there were differences in mortality the first season between the two plot-types. Plots were established block-wise with 50 blocks (pairs) on each site. The spring scarification was made with a hoe during 22-23 of April.
Technologised Parenthood: An Ethical Implacation of Human Reproductive Cloning
Science and technology has been the bedrock of human growth and dynamism. Man has over the years distinguished his existence from all other beings by his ability to champion and fashion his existence. Among his tools is biotechnology which actually attenuates the fears of aging and death.Human reproductive cloning stands out as one of the means through which biotechnology plans to achieve this perfect existence for man. Technological advancements in the field of biotechnology are now in the threshold of human procreation.Human reproductive cloning is seen as an assisted method of reproduction which creates a newborn that is genetically identical to another human being.Human reproductive cloning as a technology and as a means of reproduction is not without its pros and cons. In as much as the technology promises to mention but a few, hope for the infertile couples and single parents, as well as the hope of reproduction without passing on hereditary diseases; it at the same time beeps some flashes of worry.
En fallstudie av en gallringsfri skötselmetod för gran i Västra Götaland
Resultat från 3 olika bestånd i Västra Götaland. Åldern på bestånden är 30, 50 och 50 år. Varje provyta var 100 m2. Bestånden har vuxit utan gallring och gödsling och skötts enligt en metod som kallas Hyssnametoden. Syftet med studien var att beskriva, följa upp och utvärdera effekterna av en alternativ skogsskötselmetod.
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.
Either you're in or you're out...: Inkongruens och kreativitet - ett sätt att komma in?
The media landscape has exploded during the last decade, which has lead to a massive advertising clutter. Consumers defend themselves against this intrusive marketing by creating an advertising filter that sorts and blocks. These changing conditions have lead to new and tougher demands on creators and advertisers to create more efficient marketing communication that stands out in the clutter and penetrates the consumers? advertising filter. Many creators and researchers claim that creativity is the most efficient method to stand out in the clutter and generate sought communication effects.
Framgångsfaktorer för rundvirkesåkerier i Mellansverige :
Generally, the economic health of Swedish roundwood truck transport companies has not been good. Profitability is important for maintaining the stability in the transport business, which is a condition for long-term transport planning in the forestry sector.
The scope of this study was to identify probable factors influencing the profitability of roundwood truck transport companies and quantify the influence of these factors on economic results.
The study was carried out at a major roundwood truck transport organisation in mid-Sweden and was implemented in four steps. In the first step economic results from the haulage contractors were collected and a random sample was taken from accounted net margin for the account year 2005/2006. In the second step hauliers were interviewed to identify probable success factors. At the third step data for identified factors were gathered through a questionnaire.
Unga Bestånd - en tillgång i park- och landskap : woodlandkvarter från Alnarp till Jönköping
This is a thesis about design of young stands of trees. A big source of inspiration has been Västerskog and Tor Nitzelius Park in Alnarp which both consists of a structure of squares. I wanted to examine if this type of planting could be valuable from an aesthetic and recreational point of view. One problem today is that many people believe that we have to wait for decades for a planting to grow up so that we can enjoy the ?ready result?.