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4968 Uppsatser om Tree with high conservation value - Sida 6 av 332
Zoonotic respiratory infections and great ape conservation - an emerging challenge
The conservation of great apes faces many challenges, one of which is the threat of infectious disease outbreaks. Zoonotic transmission of respiratory diseases from humans to wild great apes has recently been confirmed. Since respiratory disease is one of the major causes of
death in both gorillas and chimpanzees, this gives reason for major concern.
Little is known about the risks of disease transmission from humans to great apes in natural environments, and there is a need for systematic risk evaluation. Researchers, conservation staff and tourists spend time in very close proximity of wild great apes, sometimes during
long time periods, which poses a potential risk of disease spillover. However, the presence of researchers and tourists has been shown to decrease the risk of poaching, making the matter increasingly complex.
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.
GIS-modellering av habitat för vitryggig hackspett (Dendrocopos leucotos) som hjälpmedel i naturvårdsplanering på landskapsnivå :
The white-backed woodpecker is a forest bird being critically endangered in Sweden. The species is dependent on older forests rich in deciduous trees and dead wood. The main problem for the survival of this species is present shortage of habitat. Conservation work on this umbrella species is at present focused on finding remaining or emerging habitat networks. Large areas are scrutinized in search for suitable habitats to be protected or managed for the species sake.
En jämförelse av sitkagranens (Picea sitchensis) och den vanliga granens (P. abies) produktion :
Sitka spruce (Picea sitchensis) is a tree species that have its natural distribution along the
West Coast of North America, from Alaska in the north to northern California in the south.
Sitka spruce is a typical coastal tree species that can reach heights up to 85 meters and occurs
in single pure as well as in mixed stands.
The main purposes of this study were to describe the Sitka spruce growing characteristics and
the volume production in comparison to spruce (Picea abies). The possibility to predict future
volume production by using prognosis tools designed to be used on spruce were also studied.
The material that has been used in this study are permanent sitka trials established by the
Faculty of Forestry fixed Sitka trials and also material gathered in this study.
A literature study was also carried out in order to determine the Sitka spruce growing
characteristics.
Sitka spruce has a high adaptation and a high volume production on a broad scale of soil
types. The tree species is a pioneer species that has a fast early growth and in combination
with sharp needles it is less susceptible to animal browsing than spruce. The factor that is the
single most limiting factor for where the Sitka spruce can be planted is frost. This factor can
be limited by using plant material with a well-suited provenance.
According to the literature, the Sitka spruce has an average total volume production that is
between 20-40% higher than spruce.
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.
Materians och energins bevarande : En studie av gymnasieelevers uppfattningar
Syftet med denna studie är att undersöka elevernas uppfattningar om materians uppbyggnad och om materians och energins bevarande. Den föreliggande studien baseras på en kvantitativ analys i form av en elektronisk enkät, som föregicks av en kvalitativ analys i form av, strukturerade intervjuer och demonstrationer.Eleverna har kunskap om vardagsnära exempel, som till exempel vad en stekpanna är uppbyggd av. De ansåg att dessa är exempel på materia men när det gäller mer abstrakta begrepp som ljus, magnetfält, skugga, vakuum, värme och ljud uppvisar eleverna mer osäkerhet och brist på kunskaper. Hälften av eleverna svarade att luft är materia, vilket tyder på ?gasblindhet? hos de övriga.
Är förekomst av knäckesjuka i tallföryngringar mindre på stora naturvårdsaspar än på aspsly?
Pine twisting rust (Melampsora pinitorqua) is a parasitic rust fungus found all across Sweden causing damage resulting in lower quality and reduced tree growth in pine stands. In Sweden, the fungus is dependent on two alternate hosts; European aspen (Populus tremula) and Scots pine (Pinus sylvestris). Pine twisting rust has five different spore stages, two of them (uredinio- and teliospores) on the leaves of aspen. Injures on aspen caused by pine twisting rust is not extensive. On the other hand, when it infects the annual shoots of Scots pine it often results in a bent steam or even a top shoot breakage.
Levande Skogsbruk : om problem i ett naturvårdsärende
In this study, some aspects of communication that are creating problems in a
chosen forest conservation case are explored. Focus is on how the manager of a
forest experience how he is treated during a formal decision of conservation.
The paper also gives introduction to communication theory as well as to
present forest policies in Sweden. Explanations of the most common concepts
and terms in forest conservation is presented and such a understanding is necessary if the reader is to acquire enlightment from the material and the following
discussion.
This paper focus on a conflict between the county administrative board, a
Swedish regional authority, and a private forest-manager. This is a case where
the manager feels that the authority is forcing a sale of land, because the forest
is being turned into a conservation area. The problems are not just economical,
the manager feels mistreated and left out of the discussion, and the negotiation
is long and problematic as shown in the interview and the case study.
In the study, an in-depth interview is made with the manager of the forest,
and a case study has been made based on the documents in the case attained
from the county administrative board.
Produktivitet och lönsamhet vid skogsbränsleuttag i klena gallringar : en tidsstudie av Vimek 608 BioCombi i contortabestånd
The annual demands for forest fuels increases in Sweden. At present, large unutilized biomass resources is found in young, dense forests from which about five million oven-dry tonnes (ODt) (23 TWh) could annually be extracted as forest fuel. But harvesting small trees give high logging costs and new cost-efficient harvesting techniques are therefore required. The aim was to study the productivity of Vimek 608 BioCombi in forest fuel thinning of Lodgepole pine and to calculate the economy of the harvesting and estimate the thinning quality. The time study was performed in Åmarken in the county of Västerbotten.
Vindfällning i naturliga och skapade bryn och kanter :
The aim of this work was to study if the edge of the forest is more resistant to heavy winds than the trees located further in from the edge, and how this edge effect changes between different types of tree species and site types.
The data was collected from an electric power line going from the north to the south of
Sweden. The mean value of the clearcutted area around the power line was 120 meters. The
main direction of the storm in January 2005 was west-southwest and thus the power line was a perfect place for gathering a large data set.
The main parameter studied was the damage frequency at the edge of the forest compared to
the trees located further in from the edge (up to 100 m from the power line). Tree species mixture, soil moisture class, soil type, topography, stand height, stand height of the stand on the other side of the power line and wind exposition was estimated.
The results showed a distinct edge effect. The edge of the forest had clearly lower damage frequency for all tree species.
A marked difference was observed between tree species and damage frequency.
Retention of stumps on wet ground at stump-harvest and its effects on saproxylic insects
Low stumps represent on their own up to 80% of the dead wood remaining on clear cuts and therefore supply suitable habitat for saproxylic insects i.e. insects depending on dead wood for their survival. Recent stump harvesting activities threaten this substrate of ecological importance and increase the anthropogenic negative impacts on these species. Because of technical and environmental reasons (nutrient leakage, erosion) guidelines for stump harvesting recommend to retain stumps standing in wet parts of clear cuts. However, stumps in wet positions might not be a satisfactory substrate for saproxylic insects and therefore might not be as much used as stumps in dry positions.
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.
Vattensork och åkersork - skadegörare i svensk fruktodling
There are two species of voles that cause damage in Swedish fruit production: the water vole (Arvicola terrestris) and the field vole (Microtus agrestis). Both species make the most damage during the winter season. The water vole makes subterranean burrows and cause serious damage by gnawing on the tree roots. The field vole seldom makes burrows and gnaws the bark at the base of the tree trunk. In recent years there have been several reports about increasing vole damage.
Användning av satellitdata för lokalisering av skogsområden där lövröjning bedöms angelägen : en analys av användbarheten med fjärranalys som hjälpmedel till röjningsrådgivning
This master thesis project is a part of a project called ?Järboprojektet? at the regional board of forestry, the district of Gästrikland. The project will give answers to questions regarding if an analysis of satellite images can be used to contact and inform landowners of the located areas where precommercial thinning is useful. The whole project is a part of the National Board of Forestrys IT-stake where the analysis of satellite images will, at the latitudes possible, be adapted to each district in purpose to identify these areas in need of precommercial thinning. This master thesis project is based on a field inventory of identified objects where precommercial thinning is useful.
Metoder för kulturmiljöanalys
Questions concerning the Cultural Heritage must be integrated in social planning.Therefore there is a need for adequate methods for cultural environmental analysis, toreceive knowledge that is relevant in an integrated conservation. The thesis is a review ofmethods for cultural environmental analysis and discusses the qualifications necessary fora method in order to receive adequate information as well as it discusses what kind ofinformation to be considered relevant. The thesis also analyzes a specific method forcultural environmental analysis in order to exam if it has got the qualifications concludedas necessary if it is to be used in an integrated conservation. The conclusion is that amethod for cultural environmental analysis should collect information about the entireenvironment (integrated information about nature and culture, in a historical perspectiveand how it is today), about social structures, physical remains (buildings etc) and what thecollected information tell about the history of the studied area, as well as what is importantin the landscape of today. Information about how the environment should be treated in thefuture is also of importance.