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227 Uppsatser om Scots pine. - Sida 5 av 16
Kan markfuktighetskartor användas för att hitta skogsmark med hög bonitet? : ett gis-baserat försök med dtw-index och laserskannad övre höjd
The depth-to-water-index (DTW-index) is derived from digital elevation models (DEM) to map soil wetness, in terms of distance from soil surface to the ground water table. The aim of this GIS based study was to investigate the existence of a relationship between DTW-index and forest site productivity (SP). The belief of such an assumed relationship was based on knowledge that the ground water level is related to site properties that can either promote or impede tree growth.
Data primarily comprised rasters of the Krycklan catchment in northern Sweden and depicted DTW-index and a laser scanned vegetation height. The 100th height percentile of each pixel in the vegetation raster was assumed to mirror the top-height, letting it act as a relative measure of SP within a delineated area of equal stand age.
Minskad trädtillväxt under Lilla sitiden? : En dendroklimatologisk jämförelse mellan nutid och 1600-talet invid trädgränsen i norra Skandinavien
During the period called Little Ice Age (1400 ~ 1900) the climate of northern Europe was in an annual year-basis overall colder than it was before and after that period. The numbers of short, cold and rainy summers and long, bitter-cold winters where often repetitive under the approximately 500-years the period lasted. In Scandinavia, the coldest time during this period is estimated to have started around the end of the 16th century and lasted to the beginning of the 18th century. Trees growing at the tree-line are limited by temperature for their annual growth and hence showing differences of growth during changes in the climate, a method called dendroclimatology. The variations of growth can be read in the tree-rings either by analyze the width of the ring or by look into the density of the wood and is used to reconstruct past climates.
Skötsel av älgskadade bestånd :
Sweden has today the highest moose (Alces alces) population in the world. The population has been very high since the late seventies and in the beginning of the eighties there was a big ?moose explosion?. The main food source for moose during the winter is young pine (Pinus sylvestris) and birch (Betula spp.). The high moose population has therefore lead to high damage on pine forests over big areas.
Ståndortsanpassning och produktionspotential för björk i Gävleborgs län
Large amounts of birch-timber are imported to Sweden, from particularly the Baltic States, since the domestic production can?t support the pulp industry. The goal of this study was to show the potential of birch and the area?s most suitable for birch production. The study was limited to Gävleborg County.
Using site characteristics, site index (SI) for birch was estimated on all National Forest Inventory plots in Gävleborg County.
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.
Mätning av stamdiameter med markstående scanner :
Booth for operational planning of harvesting and for long term planning, data is today collected manually. Intensive objective field inventories are usually too expensive. To enhance optimisation of timber flow from forest to industry Moore efficient methods for measuring tree stems of standing trees are needed. The performance of terrestrial laser scanners have improved and these could possibly be used within forestry in the future. The objective of this study was to validate how a terrestrial laser scanner could be used to measure stem diameter, and to test how the errors depend on distance from the scanner and tree species.
Two plots (one pine and one spruce) were used for this study.
Fuktkvotens inverkan på oljeupptag och pigmentinträngning i tall (Pinus sylvestris L.) och gran (Picea abies L. Karst) vid impregnering med Linotechmetoden :
Wood has always been an important material for people, and it is used for many applications. As for example, fuel for cooking and heating houses, construction materials and for constructing means of transport. Since wood also is a material that with time biologically degrades due to activity by micro organisms and wood fungi it is important to find ways to protect and further lengthen the life span of the material when in service. One method is to decrease the amount of water in the material by impregnation with an hydrophobic oil. The Linotech method which uses only pure linseed oil is one such possible method.
The aim of this study was to investigate the possibility to at the same time impregnate and stain/colour wood samples of pine and spruce by using the Linotech method.
Evaluation of an ectomycorrhizal macrofungi as an indicator species of high conservation value pine-heath forests in northern Sweden
Since the 1950s, the development of modern rotation forestry in boreal Fennoscandia has resulted in a severe reduction of older forests, and a high degree of fragmentation among the small patches that remains of old forest. In Sweden, when performing conservation value assessments in order to identify and preserve the remaining forest habitats, the government authorities use to a significant extent a set of indicator species that indicate habitats of high biological conservation value. One species considered to indicate high conservation values in pine-heath forests is the red-listed ectomycorrhizal (EM) macrofungi Sarcodon scabrosus (Fr.) P. Karst. In the present study, the validity of using S.
Markberedningens, planteringspunktens och behållardjupets inflytande på granminiplantors etablering i fält :
A new type of forest tree seedling, called mini seedling, has been developed by the University
of Dalarna in Garpenberg, Sweden. Compared to traditional containerized seedlings
that are grown for 1 ? 2 years, mini seedlings are grown for only 10 weeks. The mini seedlings
are small, easily planted, cost effective, and reduce the amount of chemicals used in
the nursery. Research has shown that mini seedlings tend to have higher overall survival
rates than traditional container seedlings.
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.
Urvalsdesign för SCB:s undersökning av föetagens ekonomi
Tree fiber lengths controls properties like strength and smoothness in paper and other wood products. For forest researchers it is of interest to be able to determine the fiber lengths in standing trees. Mo?rling et al. (2003), among others, have developed methods to estimate fiber length distributions in standing trees without damaging them.
Om matematikundervisningens svåra konst. Ett sätt att undervisa abstrakt bevisföring
Tree fiber lengths controls properties like strength and smoothness in paper and other wood products. For forest researchers it is of interest to be able to determine the fiber lengths in standing trees. Mo?rling et al. (2003), among others, have developed methods to estimate fiber length distributions in standing trees without damaging them.
Algbiomassa som gödselmedel till gran och tall
För att växter ska växa bra krävs det en mix av olika näringsämnen där de två viktigaste näringsämnena normalt sett är kväve (N) och fosfor (P). Det är viktigt att mixen av olika näringsämnen passar växtens behov samt att näringsämnena är möjliga för växten att ta upp. Det får inte heller vara för mycket av ett näringsämne då detta kan leda till förgiftning. Denna studie är gjord med syfte att klargöra hur algbiomassa av grönalger i blandad mix fungerar som gödslingsmedel för små plantor av tall (Pinus sylvestris) och gran (Picea abies). Samt att hitta förklaringar över varför algerna påverkar plantornas tillväxt.
Analys av fiberlängdsfördelning hos gran (Picea Abies) och tall (Pinus Sylvestris)
Tree fiber lengths controls properties like strength and smoothness in paper and other wood products. For forest researchers it is of interest to be able to determine the fiber lengths in standing trees. Mo?rling et al. (2003), among others, have developed methods to estimate fiber length distributions in standing trees without damaging them.
Inventering av skyddsvärd biotop med hjälp av digitala verktyg
Uppsats för avläggande av filosofie kandidatexamen i Kulturvård, Landskapsvårdens hantverk, 15 hp, 2015.