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437 Uppsatser om Tree rings - Sida 2 av 30
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.
Vad styr förekomsten av sälg och asp? : en studie av olika beståndstyper inom Hamra kronopark, Dalarna
Aspen (Populus tremula L.) and goat willow (Salix caprea L.) are two important tree species in the aspect of nature conservation. Due to the elimination of forest fires, a former negative attitude towards deciduous trees in forestry and a strong herbivore pressure, these tree species have been negatively affected during the last fifty years. The aim of this study was to investigate whether the occurrence of aspen and goat willow could be related to either human impact or to site properties, such as ground moisture and vegetation type. A side study included an inventory of a number of cyanobacterial tree lichens on aspen and goat willow in order to try to relate the occurrence of these lichens species to stand history and stand properties.
The study was performed in Hamra State Forest in northern Dalarna. Nature reserves were compared with stands in managed areas.
Fantasygenrens kvinnoskildringar : Fördomar och möjligheter i den fantastiska litteraturen
In this essay a conclusion about the way female characters are portrayed in fantasy novels will be attempted through an analysis of one selected female character from each selected novel. The works that have been chosen are; J.R.R. Tolkien?s The Lord of the Rings, Robert Jordan?s The Eye of the World and A Game of Thrones by George R.R. Martin.The analysis will be done with the help of examples and theories from both feministic criticism and gender studies.
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.
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.
Does tree removal along railroads in Sweden influence the risk of train accidents with moose and roe deer?
After the storm Gudrun in 2005, the Swedish Transport Administration started clear-cutting of railroad corridors to reduce the risk of trees falling down on the tracks. Simultaneously, train accidents with moose and roe deer have become more frequent and the costs for consequent delays and repairs of engines are of growing concern. There is reason to assume that tree-clearance of railroad corridors may have contributed to an increase in number of accidents with moose and roe deer because the cleared areas provide attractive forage and thus may attract wildlife. The objective of my study was to investigate how clearing of trees affected the number of accidents with moose and roe deer. I compared deer-train collision frequencies before and after clearance of the selected railroads and compared these with uncleared control railroads in a BACI (before-after control-impact) approach.
Människans roll i skogslandskapets trädslagssammansättning, en studie i Ångermanland
Human presence has always influenced the surrounding areas, the forest as well. Structure and species composition have changed during human land use. Knowledge regarding these changes should be of great interest for conservation and forestry. We have analyzed human impact on the tree species composition on five study sites during 2000 years in Ångermanland, Sweden. More specifically the change in tree species composition in percentage amongst alder, birch, spruce and pine over time.
Faderskapsanalys av tallfrö från Västerhus fröplantage : Skillnaden i pollenkontaminering mellan öppen pollinering och pollinering inom ett avgränsat system
In this study, pollen contamination (measured by the number of seeds pollinated by pollen not belonging to any of the clones on the seed orchard) is compared between open pollination and isolated pollination environments in a Scots pine (Pinus sylvestris) seed orchard called Västerhus, located outside Önsköldsvik. In this seed orchard a tent experiment is taking place. Skogforsk has built six large tents covering 12-14 trees with each tent. Fertilization patterns were compared between one tree in a tent with a supplementation of pollen from five clones not represented in the tent and another tree of the same clone subject to open pollination outside the tents. By using DNA markers the paternity was determined for 48 seeds from each tree.
Faderskapsanalys av tallfrö från Västerhus fröplantage : Skillnad i pollenkontaminering mellan öppen pollinering och pollinering inom ett avgränsat system
In this study, pollen contamination (measured by the number of seeds pollinated by pollen not belonging to any of the clones on the seed orchard) is compared between open pollination and isolated pollination environments in a Scots pine (Pinus sylvestris) seed orchard called Västerhus, located outside Önsköldsvik. In this seed orchard a tent experiment is taking place. Skogforsk has built six large tents covering 12-14 trees with each tent. Fertilization patterns were compared between one tree in a tent with a supplementation of pollen from five clones not represented in the tent and another tree of the same clone subject to open pollination outside the tents. By using DNA markers the paternity was determined for 48 seeds from each tree.
Utsmyckningsidentitet En studie om äldre bronsålderns utsmyckningskombinationer funna med halskragar och halsringar.
The aim with this essay is to explore the possibility that jewellery was worn in combinations during the Bronze Age in the south of Sweden and Denmark as a way to show identities. By examining neck-collars and neck-rings and the jewellery found with these objects in graves, I have managed to find a few combinations that re-occur within regions which I think point towards ways of expressing different identities.To fully explore the subject I have also examined the design of the neck-collar to see if the designs have the same regional difference as the combinations. Though there is some difference between regions it is the similarity of the design over regions that stand out. It is possible that the design of the neck-collar has shown a different meaning than the jewellery combinations.There are similarities between the jewellery found in combinations in the graves and the jewellery found in hoards. Neck-collars and neck-rings found in combination with other jewellery in hoards show a greater regularity over the south of Sweden and Denmark then those combinations found in the graves..
Structure and tree diversity of lowland limestone forest on Seram Island, Indonesia
There have previously been very few studies of forests on Seram Island in the Eastern Indonesian archipelago and none before on lowland limestone primary forests. The COLUPSIA project on collaborative land use planning has therefore chosen Seram as one of two project sites. The objective of the COLUPSIA project is to establish collaborative and equitable land use planning. In order to achieve its objective the COLUPSIA project aims to improve understanding of traditional resource management and how it interacts with governmental systems, as well as enhancing knowledge about tropical landscapes and ecosystem services.The aim of this study was to contribute to the COLUPSIA project through describing lowland limestone forest on Seram Island in respect to (1) forest structure, (2) tree species richness and (3) tree species composition. We set up 5 plots, each of 0.2 ha, at one site, Mawalai, and collected data on tree variables (tree diameter ?10 cm) as well as for some other life forms and environmental data.
Maximerande av ekosystemtj?nster i urbana kulturmilj?er: En fallstudie om tr?dval i Pommerska tomten i Mariestad
The purpose of this work has been to explore what ecosystem services a small green area in an urban
environment can offer and whether specific trees can be used to maximize regulatory ecosystem
services in a cultural-historical environment. Additionally, it investigates whether there is any
difference in ecosystem services depending on whether these trees, or trees that better fit into the
cultural-historical environment, are used. Through simulations and comparisons with existing trees in
Pommerska tomten, Mariestad, Sweden, a pocket park within a national interest area, different
hypothetical tree planting options are analyzed and evaluated. To measure ecosystem services, the
website My-Tree, developed by the US equivalent of the Department of Agriculture, was used. By
inputting data about the tree, such as location, species, vitality, stem diameter, and solar exposure,
My-Tree calculates some of the ecosystem services the tree provides.
Gäddan & fisket i Ringsjöholm : en osteologisk metodstudie i säsong & bevarande
This paper presents the results from an osteological method study of the Ringsjöholm fishbone material. Ringsjöholm is located in Scania, southern Sweden and is 14C dated to 5960-5200 B.P. The aim of this paper is to critically analyse methods used on fish bone material in estimations of season. Three different approaches were used to estimate the fishing season at the Ringsjöholm settlement; 1) identified species, 2) size estimations of the pike based on Enghoffs (1994-95) regression formulae of os dentale, and 3) growth rings of the pike vertebrae.The identified species and the size estimations of the pike points to the fishing being active both during spring and summer. Growth rings analysis of the pike vertebrae didn?t give any quantitative results because of fragmentation.
En inventering av säregna trädformer funna i Sverige
In Sweden and in Scandinavia the amount of tree species are rather few. However many different forms of trees arise due to mutations and gives rare appearances like cut-leaved and hanging forms. In some cases these trees are interesting as cultivars and a few of them have become popular garden trees. The knowledge of the original trees and early propagation is meagre.In this study a selected group of trees were found through search of literature. Eight tree forms were chosen and investigated in situ.
Beståndsutveckling i stormskadade granbestånd
The storm Gudrun in 2005 led to massive windthow damage in forests in southern Sweden.
Since then there has been a growing interest in factors influencing wind damage in above all
Norway spruce (Picea Abies) stands. Although many other interesting areas still need to be
examined. In 2005 there where a lot of stands that suffered different degrees of damage, a lot of
these stands weren?t cut, but instead left to grow. The future development of these stands is
uncertain and the guidelines are unclear.