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455 Uppsatser om Basiphilous pine forests - Sida 21 av 31
Skogsbrandens påverkan på död ved :
Fire is an important ecological factor, but its consumption of coarse woody debris, CWD, has hardly received any attention. In this study, I investigate the consumption in relation to the time of initial flame exposure and propensity for continued combustion of standing CWD of pine (Pinus sylvestris).
Two types of CWD were studied. Firstly, wood that had been dead for one to ten years. Secondly, wood that had been dead for several decades. In the burning experiments, logs of approx.
Anpassad skötsel - exempel på hyggesfritt skogsbruk i Mellannorrland :
Total protection is often the option chosen when protecting forests with high environmental values. An alternative to total protection is application of management regimes that do not interrupt continuity of tree cover. This study focuses mainly on continuous cover forestry (CCF) in forest stands already protected. All objects are situated in the county of Jämtland in northwest Sweden.
The purpose of the study was to attain a greater knowledge about CCF practices.
Volymmätare för tall- och grankott
This thesis describes the planning and development of a volume meter of pine and spruce cones. The product was designed and developed for Stigsjö Skog och Frö AB in Härnösand. It was developed taking into account a number of requirements set by the supervisor David Zetterlund. The main requirements were that the volume measurement would be fast and give accurate results. These are two requirements that are missing in today's volume measuring method which is very problematic for the company.The plant was visited several times in Härnösand, mainly to discuss the generated concepts with the supervisor and perform tests on the prototype.
Wild boar paradise : What makes the Swedish wild boar reproduce more or less successfully?
Due to the growing wild boar (Sus scrofa L.) population in Sweden there has been an increase in wild boar related traffic accidents, damage on cropland, and conflicts regarding the management of the wild boar. Knowing what makes the wild boar reproduce and survive more or less successfully in different geographic areas is an important part of managing the population. According to previous studies the wild boars rate of increase varies from county
to county. The aim of this study was to test, on the county scale level, if landscape composition and diversity as well as people and hunter densities might be the reason for this
variation. The first hypothesis was that a big proportion of forests and cropland would increase the rate of increase.
Skogspolitik i Sverige
For a long time the Swedish forests were used by the landowner?s mainly for providing wood to the household itself. The wood was not, to a greater extent, considered a product to be sold. During the 1800s the industrial era led to a demanding need for wood in the industry and thus the use of forest, forest production kicked off. The forest production was not regulated by law, which led to a differentiated forest production over the whole country without consideration of re-growth.
Gallring med vinkelkran : en jämförande studie av skördarkran med och utan horisontellt ledad vipparm
One of the most important components of a harvester is the crane. Most harvester cranes are only possible to pivot (or horizontally rotate) at the crane pillar. Cranab in Vindeln, Sweden, has developed a new type of harvester crane which has an extra pivot point on the outer boom. This makes it possible to reach around residual trees, easing thinning work in dense stands.
The aim of the study was to analyze if the use of a pivoting outer boom (POB) crane gave an increase in thinning production and if there were any differences in time consumption between the work elements for the POB crane and a conventional crane. A Valmet 911.3 equipped with a POB crane was used in the study.
Qualities and supply of suitable dead wood for Ceruchus chrysomelinus and its dispersal pattern in a translocated population
The wood-living beetle Ceruchus chrysomelinus is a rare species connected to natural
forests. In Sweden, it is red-listed as endangered (EN) and an action plan for its preservation
has been done by the Swedish Environmental Protection Agency. In this work I have
therefore investigated how a translocation of the species succeeded after 17 years. I aimed
to study the species dispersal biology, its substrate preferences and the supply of suitable
wood on this site. The study was performed during 2012 in Pansaruddens nature reserve
close to Uppsala in Sweden, which is a spruce dominated forest.
Examination of mycorrhizal associations of Allanblackia stuhlmannii : a tree under current domestication
Allanblackia is a tree genus native to humid forests in West, Central and East Africa. Its fruits contain large seeds from which edible high-quality fat can be extracted. In order to create a sustainable supply chain of Allanblackia seeds, a domestication program has been initiated with the purpose to enable smallholder farmers to grow the tree as an agroforestry component and cash crop. More knowledge is required to understand the tree?s biology and possible symbioses involving soil microorganisms with plant growth enhancing poten-tial.
Produktionsvåtmarker mot övergödning
In ambition to produce more and better harvests, artificial fertilizers are used to produce a better growth of crops in the agriculture landscape. This contributes to leakage of nutrients. Our forests also exhibit a leakage of nutrients. Air pollution contributes to more nutrients. High precipitation with high water flows as a consequence seems currently to occur more frequently in the county of Halland.
Vindarnas Boning : En studie av monumentalistiskt historiebruk
Monuments are raised all over the world of several different reasons. A monument dosen´t only refer just to itself, it also tells something about the historical context they are risen into. The overall purpose of this study is to try to reveal how history is used through the process, and rising of the monument "Vindarnas Boning" in Karlstad, Sweden 16/6, 1967. The historical narrative around this monument is about to show the importance of the esthetics, the main forces around the monument and last, how the monument legitimacy is maintained. Throughout those analytic tools, according to this study, I will try to examine possible other reasons behind this monument than the official one, who is to act as a remembrance of the finnish immigrants who settled in the unpopulated deep forests of Sweden and enabled to maintain a minor community separated from other influences, during the 16 th century and onward.
Klibbalens gödslingseffekt på volymproduktionen i ett blandbestånd av gran och klibbal : en simulering i Heureka
A secondary and a pioneer tree species can with advantage be included in a mixed stand to increase the use of sunlight. Nitrogen-fixing plants have been shown to increase the supply of nitrogen in the soil by, for example, litter fall. This deposition acts as a biological fertilization, which may be used by non-fixing plants. Alder is a nitrogen-fixing, pioneer tree species that loses its nitrogen-rich leaves late in the autumn. The aim of this study was to examine the effect on the total volume of production, when different proportions of nitrogen-fixing Alder were part of spruce stands.
Nya träd för stadsmiljö
Trees in urban environment are exposed to extreme conditions, foremost the ones that grow in the hard packed soil along our streets. They are also exposed to damaging insects and fungal diseases both local and new ones spreading from South Europe. The global warming with warmer temperatures provides a longer growing season, making it easier for insects and fungus to establish a habitat. Based on these facts new tree species need to be available for future urban plantings.To determine what these trees would be an interview study began. Six people were selected who have experience in the field of urban environment planting.
Det gör ont när stockar spricker!
The aim of this study was to provide SCA Forest Norrbotten District with material to assist in their work towards decreasing the frequency of bucking splits in their saw timber logs. SCA Forest supplies the Munksund sawmill with pine timber. Periodically the sawmill experiences problems related to bucking splits in their logs.
The purpose of this study was to find an available method to measure the occurrence of splits directly on incoming timber. The ambition was also to gain some knowledge about possible variations between different logging crews in terms of split frequency. If possible, this information could be used to investigate if certain crews produced more splits than others, and thereby making it possible to provide feedback to the logging machine operators.
The study consisted of two major parts, a literature review, and a practical sawmill study.
Förekomst av törskate (Cronartium flaccidum, Peridermium pini) på tall (Pinus sylvestris) i relation till markfuktighet och fältskikt : en studie om 2000-talets törskateepidemi i norra Sverige
Resin-top disease is a rust fungi that occurs both as a host alternating form, Cronartium flaccidum G. Winter., and as a non-host alternating form, Peridermium pini Pers. The host alternating form can use a variety of hosts but the most commonly used species in the boreal forest is Melampyrum sylvaticum. In Scandinavia the Resin-top disease infect Scots pine, Pinus sylvestris L. The fungus infects the needles through the stomata and then grows through the branch to the stem where it strangulates the vessels transporting water and nutrition to the treetop, which kills the top.
Clear-cut and substrate characteristics important for the occurrence of the beetle Upis ceramboides
Disturbances, such as fire and wind, are important for saproxylic beetles (= beetles depending on decaying wood) to gain substrate in boreal forests. Clear-cutting is an example of a man-made disturbance. Measures such as prescribed burning have been made to resemble natural disturbances. The aim of this study was to see which clear-cut characteristics are important for the occurrence of the saproxylic beetle Upis ceramboides.
This is a species favored by open habitats and is said to respond positively to forest fires. The distribution area in Sweden for this species has decreased during the last two centuries and I wanted to see if there were differences between clear-cuts in Hälsingland, where it is very
rare and decreasing, and Norrbotten where this study was conducted.