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4968 Uppsatser om Tree with high conservation value - Sida 4 av 332

The shift in forest and tree limits in Troms County - with a main focus on temperature and herbivores

To better understand how various factors affect the establishment of forest and trees around the tree line-ecotone, this study was conducted in Troms County, Norway. The altitude of different forest and tree limits together with the surrounding vegetation type were collected during August 2011. Comparisons of the collected data were made with previously collected data from the same sites conducted 1914 and 1915. On average the forest limit has expanded with 26 meters in altitude, however, an expansion is not statistically significant for the whole area. The tree limit has significantly expanded in altitude.

Lämpliga främmande trädslag för Kalmar och Mönsterås kommuner

This report concerns the for Sweden foreign tree species hybrid larch, hybrid aspen and poplar, and focuses on the area Kalmar and Mönsterås municipalities. The report shows that there are not only advantages with these species. The larch, the most common of the alien tree species has the greatest problems due to that its timber is difficult to sell in the area but also the Larch´s poor pulp quality and is more likely to be damaged by wildlife than the spruce is. Hybrid Aspen is much easier to sell and is used like regular aspen for match wood and textile pulp. Its disadvantage is the high cost for plants and to prevent damage from wildlife.

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.

Tree species traits response to different canopy cover for 34 tree species in an enrichment planted tropical secondary rain forest in Sabah, Malaysia

Tropical rain forests only cover around six percent of the world?s land area and contain around 70 % of the world´s animals and plants. Tropical rainforests have been, and still are, negatively affected by human activities. These activities lead to forest degradation which has negative impacts on production and biodiversity. Between 1970-1980 forests in Borneo, Sabah, Malaysia, was subjected to intense logging.

Dendroklimatologisk analys av lokalklimat vid Grövelsjön i Dalafjällen

Climate on earth is getting warmer, which effects earth?s energy balance and so forth the ocean and atmospheric circulation.  In many sub-polar regions on the northern hemisphere changes due to warming of the climate can be observed. Some examples that already have been observed are shifts in tree line, towards higher altitudes and latitudes, increased ablation of Swedish glaciers and melting of the permafrost on the Siberian tundra. In Sweden climate change scenarios tell us that it will become warmer and that a higher amount of precipitation in form of rain will be an effect from this. To study climate changes in Sweden, transition zones are useful in order to observe changes in distribution of species and animal populations.

Trädens utveckling efter att de har lämnats som naturhänsyn : tillväxt, mortalitet och strukturell förändring 6-18 år efter avverkning

Today green tree retention, together with leaving dead wood, is a common practice with the aim to reduce negative impacts on biodiversity and environment due to clear-felling. To better understand whether this conservation practice also makes a long-term difference, it is important to know what happens to these trees after harvest. Few studies have made an assessment of what happens to retention trees over a longer time period. In this study I inventoried retention trees that were left at clear-cuts six, twelve and eighteen years ago. I carried out a re-inventory of 57 retention patches (divided into free-standing tree groups, small swamp forests and edge zones) and free standing dead trees, spread over 25 previous clear-cuts in central Sweden.

Inställning till och val av livsmedelsprodukter bland personer som är över 55 år

Data retrieved from airborne laser scanning represents a new source of forest data. Today, the technology has matured so that it can function in an operational environment. The aim of this study was to compile areas of application of laserdata in forestry. Moreover to analyze costs and accessibility of laserdata. The goal was to provide private forest owners information to support assessments of possible benefits of laserdata.

Produktivitetseffekter av flerträdshantering

The main purpose of this study is to investigate the productivity effects of multiple tree handling in thinnings. Other important elements have been to investigate in which extent multi-tree handling is used in stands with different stem volumes and the impact of collecting partially delimbed fuelwood assortments has on harvesting performance. The study is based on data from thinnings in Sydved and contractors' operating activities. Collection and compilation of operating schedules, number of stems and surveyed volumes from several contractors and a large number of executed orders underlying the results. Multiple tree handling is used to a much greater extent at lower average stem volumes. Prediction models for productivity of the multiple-tree handling harvesters in the study differ from the productivity models for single-tree handling. In the model developed in this study productivity is not as dependent of stem volume as reference models.

Konflikten mellan bevarandekrav och tilläggsisolering : The conflict between conservation requirements and additional insulation

Sweden has formulated ambitious energy goals which signify that by year 2050 the energy usage should be halved. One of the objectives is the reduction of energy usage by 20% by year 2020 and that it should be compared to the usage of energy from 1995. In parallel with increased energy requirements for buildings the demand on housing conservation, by highlighting also buildings from the last 50 years as part of the building heritage, continues to enhance, which in theory means that there is a conflict between these.The law will never be able to point out unique buildings and PBL (planning and building act) is not especially concrete. The National Housing Board has tried to make this more concrete by the new BBR regulations though there are still an enormous variety of interpretations.This report deals with the conflict between conservation requirements and additional insulation of the building envelope and is limited to multi-residential buildings built between the years 1945 and 1975. It is the stock with the greatest energy consumption and that is where the big challenge lies.

Goat production in Laos and the potential of using Erythrina variegata as a feedstuff

Lao People?s Democratic Republic (PDR) is a country where the majority of the population works within the sector agriculture in one way or another. The number of goats are increasing and the animals can be an important income source for families. However, during the dry season, lack of feed is a great problem for the farmers. Fodder trees have shown great potential as dry season feeding, due to that the trees often hold green and fresh leaves a long time into the season, compared to grass that dry out quickly.

Kiviksgraven : analys av dess historia och framtid sett utifrån bevaringsfrågor

This essay focuses upon the Kivik monument and its conservation difficulties, since its discovery at 1748 until modern time. The Kivik monument is found in southeast of Scania, and dated within the Bronze Age period. The perspective of the conservation on the monument has merely been on the monuments inner cist of stone and the rock carvings on the cist-slabs. When the monument was first archaeological examined at 1931, its sizeable cairn (75 m in diameter) had almost vanished and the cist was sheltered by a casing of concrete and metal roof. Between 1932 and 1933 the monument has undergone a large-scale restoration, and this criticized restoration resulted in a low antiquarian value with the responsible authority.

Julgransodlingar i Sverige : utbud, efterfrågan och lönsamhet

This thesis is about Christmas tree plantations in Sweden, and if its profitable to produce Christmas trees in Sweden. Sweden has 4,3 million households, 3 million of these households buys Christmas trees. 80 % of these Christmas trees are Norway Spruce (Picea abies), which is the most common Spruce in Sweden. Every year over 170 000 Christmas trees are imported to Sweden. The main import comes from Denmark.

Prestationspåverkan av flerträdshantering i klena gallringar

The aim of this study is to investigate how multiple tree handling harvesters perform compared to earlier developed standards. The study shows that multiple tree handling harvesters are more efficient in thinnings stands with mean stock volumes less than 0,12 m3fub per stock. The increased efficiency is different for different mean stem classes. In stands with a mean stem volume of 0,04 m3fub per stock, the increase can be as high as 40 percent while it is about 10 percent in stands with a mean stem volume of 0,12 m3fub. Comparisons have been done between stands that are felled with partly limbed stands and stands without partly limbed assortments. The difference in performance is clear and shows that the partly limbed assortments strengthen the multiple tree handling harvesters positive effects in low dimension thinnings.

Hållbart skogsbruk och naturvård ? ett skogsägarperspektiv

The Swedish government has set up 16 environmental goals for Sweden to achieve. One ofthem is ?Living forests?, which is the foundation for the ?National strategy for the formalprotection of forests?. The ?National strategy? puts the private forest owner at the centre ofattention in order to achieve the environmental goal ?Living forests?.

Inventering av Hårsbäcksdalen och Örsundaåns övre dalgång ur ett geodiversitetsperspektiv

The area around the stream Orsundaan, which runs trough the valley Harsbacksdalen, is famous for its beautiful landscape. The upper area of Orsundaan and Harsbacksdalen is situated just south of Heby in Uppland, Sweden. Even though the area is protected by different nature conservation acts, it is difficult to find any information about the geodiversity in the area. Geodiversity, or geological and geomorphological diversity, includes the concepts of geoprocesses and geoelements. Very high geodiversity could be seen at an inventory of the geomorphology in the upper area of Orsundaan and Harsbacksdalen.

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