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3373 Uppsatser om Fast growing tree species - Sida 3 av 225
Stubbehandling med pergamentsvamp och urea mot sporinfektioner av rotticka i bestånd av hybridlärk
Root rot is a big hurter and a huge economic problem for the Swedish and European forestry. The severest hurter is Heterobasidion annosum (Fr.) Bref and it occurs as two different species in Sweden. Commonly referred to as the P-type (Heterobasidion annosum s.s. (Fr.) Bref.) and the S-type (Heterobasidion parviporum Niemelä & Korhonen). Therefore a lot of research has been carried out in this topic to find a solution and reduce this problem, one alternative that have shown to be profitable is stump treatment in thinnings.
Det enskilda trädet som meningsbärare : erfarenheter av två trädplanteringsprojekt i Helsingborg
Individual trees can act as carriers of meaning. When a person attributes deep meanings to a specific tree, a relationship between the person and the tree is created. To avoid conflicts between users and planners, increased awareness is required of how important individual trees may be to a person. The objective of this study was to elucidate persons? relationships with individual urban trees.
Volume and taper equations for Sitka spruce (Picea sitchensis (Bong.) Carr.), Norway spruce (Picea abies (L.) Karst.) and White spruce (Picea glauca (Moench) Voss) in Iceland
The aim of this study was to evaluate different types of volume and taper equations that can be used to predict single-tree stem volume and stem diameter at any given height along the tree stem for plantation grown Sitka spruce (Picea sitchensis (Bong.) Carr.), Norway spruce (Picea abies (L.) Karst) and White spruce (Picea glauca (Mounch) Voss) in Iceland. A number of published tree volume equations were tested and modified to predict the total stem volumes over bark but three logarithmic equations were taken for more in-depth analysis. Three taper equations were tested. Two variable-exponent equations (Kozak 1997, Kozak 2004) and one exponential equation described by Biging (1984). Data from a total of 617 sample trees were used in this study, collected from stands in various parts of the country and present different types of stands growing in different soil types and cover most of the site conditions suitable for forestry in Iceland.
Naturreservat : en bra naturvårdsåtgärd för att bevara enskilda arter och/eller bevara den biologiska mångfalden?
The examination of the adequate nature conservation methods in a natural reserve, to conserve a specific species and / or increase biological diversity is the subject of this study. This work is based on four species, that can be found during the Spring season, liverleaf, wood anemone, brimstone and woodpecker. The incidence and availability is studied and closely observed for these species in twenty forests, i.e. ten forests which are nature reserves and ten forests with the similar characteristics as the nature reserves habitat, but are not nature reserves in Gnesta mucipality, Södermanland. Measurements of the tree crown and the diameter of the tree trunks where noted to study how these factors could affect the outcome of the abundance and incidence of the four species.
Utveckling av gran, Douglasgran, bok och tall under skärm av hybridlärk :
?Development of Norway spruce, Douglas fir beech and Scots pine with a larch
shelter wood? is a report written by Per-Olof Magnusson. The thesis is a
compulsory part of forest engineer program at ?Skogsmästarskolan?, SLU,
Skinnskatteberg, Sweden.
The purpose of this report is to describe and evaluate an experiment with hybrid
larch (Larix x eurolepis) as shelter wood, and different tree species growth and
survival depending on the density of the shelter wood. The experiment is
conducted by southern Swedish forest research centre, faculty of forestry, SLU in
Alnarp.
The hybrid larch ought to be an interesting alternative to birch (Betula sp.) as
shelterwood on suitable sites in southern Sweden.
Provtagning av trädkärnor för att bedöma föroreningsgraden av klorerade lösningsmedel i grundvatten
Chlorinated aliphatic hydrocarbons (CAH´s) were used widely within dry cleaning facilities and for metal degreasing until their toxicity was discovered. PCE is still used as dry cleaning liquid. Today CAH´s are found in soil environment at places where they have been used in the past. The CAH-concentration in trees growing on contaminated land has quite recently received attention as a cheap and effective way of assessing the extent of a CAH-contamination. The method has however, not been put into use in Sweden.The aim of the study has been to investigate whether the CAH-concentration in tree cores could be used to delineate the spread of CAH in a soil environment under Swedish conditions in different seasons.
Lövsuccessioner i sluttningar längs nedre Umeälven :
Secondary deciduous forests, which have their origin in earlier pasture- and meadow-land in slopes along the lower reaches of the Ume river, are thought to contain high nature conservation values, in spite of a relatively low age. The aim of this study was to clarify how factors as historical use, exposition, disturbance dynamics and successional age influences the conservation values in these types of riparian forests and how this can be implicated in the practical work with conservation and management at Umeå municipality. Sample plots were placed in seven stands with a variation of their historical use, exposition, disturbance dynamics and age of succession. Conservation values as structure, tree-regeneration, abundance and composition of vascular plants, amount of dead wood and the abundance of signal-species were measured and registered. The species composition and especially the composition of tree species, differed between forests with different exposition and different historical use.
KLIMATTOLERANS HOS URBANA TR?D I G?TEBORG: Analys av klimatgr?nser och framtida klimathot
Urban trees contribute significantly to our society. By providing ecosystem services and a habitat that other urban species and ecosystems depend on, both biodiversity and the people in the city benefit. Some characteristics that the trees possess include functioning as biological filters for the atmosphere and water, as well as positively impacting people's mental health. However, urban trees are challenged by stressors such as pollution and a drier environment, making them particularly sensitive to climate change. The goal of this study was to estimate the expected magnitude of climate change in Gothenburg and compare it with the current urban species' natural climate boundaries to understand the extent of the climate threat and which species appear to be most at risk.
Jätteträd ? inventering, bevaring, skötsel samt rekrytering :
During the summer of 2007 I was employed by Högestad Christinehofs Förvaltning AB. My
main task was to make an inventory of giant trees at the estate. Högestad and Christinehof,which with their total possession of 13 000 ha of land is the biggest estate in Scania.
A giant tree is a tree with a diameter in breast height more then 1 meter. Trees of these
dimensions are registered by Swedish authorities. Landowners with a giant tree on their
property can receive a subsidy for cutting trees that are in competition with the giant tree.(Levenskog, 2007)
Giant trees are important for biodiversity in the landscape and there are important habitats for different insects, birds, bats, lichens and funguses.
SAMMANS?TTNING AV MAKROALGER I SVENSKA ?LGR?S?NGAR eDNA sp?rning och klimatf?r?ndringar
The aim of my bachelor?s thesis is to investigate, through a literature review, changes in the
distribution of filamentous algae as well as the general species composition of macroalgae
and diatoms in Swedish eelgrass meadows. I have also studied the possibility of tracking
these algae and diatoms in eelgrass meadows using eDNA methodology. The focus has been
on linking these changes to climate change factors such as eutrophication, temperature
increase, and anthropogenic emissions, and how these affect the health of eelgrass meadows
and their ecosystem services, such as a carbon sink and biodiversity support.
The results show that filamentous algae have increased markedly in coverage in Swedish
coastal areas between 1980 and 2021, especially in sheltered bays, indicating that altered
environmental conditions favor these fast-growing species. Genetic tracking using eDNA
demonstrated that there are functional primers for many species, particularly among brown
algae and red algae, whereas green algae require more specific primers due to greater genetic
variation.
Rekreationsanpassad skötselplan för Skedalaskogen :
In this master thesis we suggest a recreational directed forest management plan for the
Skedalaskogen. The forest is situated 10 kilometres east of the city of Halmstad and is owned by the municipality.
We have in literature and in research investigated what people like and want in the forest, how to manage the forest for recreation according to for example tree species, mixtures and density. We tried to adapt the forestry methods more to recreational thinking. We have also looked at issues like what is rare and not rare in this part of the country according to nature and forest, where people live and which connection they have to the Skedalaskogen.
The Skedalaskogen is a quite big area, totally 830 hectares. The area have about 100 000
visitors a year.
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.
Sand pits as habitat for ground beetles (Carabidae) : does the area affect species number and composition?
Sand pits are a valuable habitat which can hold many sand living species including several endangered ones. As many sand habitats with exposed sand are declining, sand pits have a potential as a substitute habitat. This study was conducted to see what effect the area of a sand pit has on species number and composition of ground beetles (Coleoptera: Carabidae). Also, the effects of other environmental variables were tested, for example the proportion open sand, vegetation cover, sun exposure and tree cover. The study was conducted in the county of Uppsala in 2008 and included 13 sand pits with areas between 200 and 180,000 m2.
Effektivare röjningssätt med kedjeröjsågen?
After the mandatory rules for clearing was removed in 1994, the clearing area has increased in Sweden. After the storms Gudrun and Per, the areas became planted with new plants, mainly spruce, but also other tree species. Storm areas are now being invaded by naturally rejuvenated birch in the tilling tracks. Since the birch often is initially growing faster than the spruce it is inhibiting the growth and is also damaging the spruce.
The purpose of this thesis is to study the new brush saw with chain and compare it with the conventional clearing saw, mainly in terms of performance and ergonomics. The results show that the new brush saw with chain is very good in almost all clearing operations compared to the conventional clearing saw.
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.