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398 Uppsatser om Exotic trees - Sida 6 av 27
En studie av viltets påverkan på Skogssällskapets fastighet i Selesjö
This degree project investigates how elk, roe deer, red deer and fallow deer can affect an estate in Östergötland. The inventories performed within this project, were completed on an estate in Selesjö, northern Östergötland. This property is used to demonstrate wildlife management.
The methods used in this study were originally developed for areas larger than individual properties. Three inventories were completed in the study. These included the recording of the number of droppings and the amount of eaten pasturage, as well as the level of damage on young trees.
Goat production in Laos and the potential of using Erythrina variegata as a feedstuff
Lao People?s Democratic Republic (PDR) is a country where the majority of the population works within the sector agriculture in one way or another. The number of goats are increasing and the animals can be an important income source for families. However, during the dry season, lack of feed is a great problem for the farmers. Fodder trees have shown great potential as dry season feeding, due to that the trees often hold green and fresh leaves a long time into the season, compared to grass that dry out quickly.
Metoder för att undersöka effekterna av naturvårdshänsynen i skogsbruket, efter den senaste skogsvårdslagenMetoder för att undersöka effekterna av naturvårdshänsynen i skogsbruket, efter den senaste skogsvårdslagen.
In 1994 a new Forestry Act was accepted in Sweden. One of the aims of the law is to raise consideration forpreservation of biodiversity. Since the new law got accepted and some time has passed, there now lie someinterest in examining whether the law has been effective towards its purpose. Methods suitable for analysishave been examined during this study. The content of this pilot study is based around five parameters whichcan be used to validate the effects of the new law.
Naturlig föryngring av lövskogar i Örebro län :
The Regional Forestry Board in Värmland- Örebro needs increased knowledge on silviculture in broad- leaved forests. This thesis is an inventory of naturally regenerated broad leaved forests, and the results from the inventory have been compared with The Regional Forestry Board?s demands on regeneration results. The result of this inventory was that the regenerated sites were suitable for broad leaved trees, but only half the number of the stands fulfilled the demands of regeneration results of The Regional Forestry Board, mainly because of gaps in the stands. The gaps in the stands were mainly caused by lack of soil preparation and seed trees..
Gremmeniella abietina-epidemin 2001 : har skogen återhämtat sig?
The fungus Gremmeniella abietina causes damage to conifers that can lead to tree death. In 1999 and 2001 the pathogen caused severe attacks in Sweden, where about 500 000 ha of pine forest were affected. Trees of all ages were attacked, but mainly forests between 30-60 years that were ready for their first commercial thinning. After recommendations from the forest agency, sanitary fellings were made to trees that had more needle loss than 85%, a total of about 50 000 ha. Economic losses have been estimated to more than one billion SEK.
Naturvårdshänsyn i boreal bruksskog : En studie om avverkningar och avverkare i skogarna runt Saxdalen i södra Dalarna
As the past century?s technological development has progressed the Swedish boreal forests have transformed into dense, highly productive, homogenous and coniferous forests. The area around Saxdalen in Ludvika municipality has long been dominated forests which have been heavily worked since the 18th century. There are in Ludvika 119 000 hectares of productive forest land. Around 70 percent are owned by forest companies and 20 by private forest owners.
Volymsrapportering vid terrängtransport av virke
This report is a B.Sc. Forestry thesis work at the school for Forest Management, SLU.
The work was an assignment from the forest owners? association Mellanskog.
The aim of the work where to investigate the economical result of removing undergrowth trees before first thinning, and a follow-up of the contractors and their compliance with Mellanskog standards.
This thesis work was divided in three parts: The first was to find a relation between the net volume from the first thinning and the cost of cleaning undergrowth trees. Secondly there was a follow-up in the field, to investigate whether the contractors have done the undergrowth cleaning according to Mellanskog?s directives.
The effects of mother trees and site conditions on the distribution of natural regeneration establishment in a Bornean rainforest disturbed by logging and fire
In the tropics, logging and wild fire can result in degraded secondary forests with lower biodiversity than in the natural forest. One way to limit forest degradation is to rehabilitate the present large areas of secondary forests. However, there is a lack of knowledge concerning the ecology of tropical tree species and further studies would be advantageous for future rehabilitation efforts of degraded rainforest. The objective of this study was to investigate how mother trees in secondary forest and different site factors affect the abundance and spatial distribution of natural regeneration of non-pioneer tree species in a tropical rainforest in Sabah, Malaysia.
The study took place in the INIKEA Forest Rehabilitation Project area, which suffered from wild fire in 1983 and has been selectively logged over both before and after the fire. Natural regeneration and site variables were inventoried in plots, while mother trees were inventoried in the whole survey area.
En jämförelse mellan två datorprogram för utbytesberäkningar :
This thesis is made on behalf of SCA's Forestry Division and is a comparison of two bucking simulation tools: Aptan (manufactured by Skogforsk) and Best/upr (from Berget Systemdesign). The data is based on 32 stands from SCA's forests in Norrbotten and Västerbotten. The objective is to compare the simulations created by the tools with the harvested volumes from those stands. Three variables are needed for the bucking simulation; these are the diameter distribution (at breast height), the relationship function between diameter and height, and the taper coefficients. The volumes of five different assortments from the stands are compared.
Undersökning av självspridning av contortatallen i norra Sverige
Over the past 40 years 600 000 ha of lodgepole pine (Pinus contorta ssp. latifolia (Engelm.) Critchf.) has been planted in Sweden (280 000 ha on SCA's forest land alone which represents about 15% of the company's total forest land area). In the early 70's SCA situated a number of experimental stands in order to investigate different aspects of the exotic tree, primarily growth rate. To be able to compare the two species plots with scots pine (Pinus sylvestris L.), this species was also planted at the same time and under the same conditions.
A number of questions should always be raised when exotic species are introduced in an ecosystem. Invasiveness, the pathogen situation and purely ethical issues should be discussed.
Naturvärden i en värmländsk bruksskog : en skogshistorisk studie av Åbengtshöjden/Bogranghöjden
In this study I have analysed the history of a forest belonging to Saxåhyttan in Värmland. The study area is 448 hectares and has been used by iron industry since the 16th century. A forest that has been used by man during at least 400 years should have few ecological values. This inventory however shows the opposite.
The aim of the study is to interpret the history of the forest in the area, i. e.
Svamparnas roller i svenska barrskogsekosystem : hur ser kunskapsläget ut hos några olika grupper människor?
Fungi are everywhere around us and recently, there has been
an increased interest in their role and importance in the forest.
The fungi have several strategies to acquire energy and nutrition; one example is a mutual symbiosis with trees and plants - another being dissolving organic materials.
Attempts have been made to better understand the circulation of nutrition in coniferous forests, and how fungi cooperate.
Trees and plants have adapted with mycorrhizae and are now interdependent which is important to consider in forestry.
A great number of fungi depend on dead wood and old trees to set fruiting bodies and spread further. These fungi also create environments for other species, such as birds and insects.
The vegetation of a forest is determined by a series of factors; tree species, how old the forest is, soil type, as well as the ability of the fungal spores to spread and establish. Furthermore, in determining vegetation, the fungi?s ability to compete in the soil matters. These factors are nearly unexplored.
Researching fungi knowledge and interest, a survey was distributed to five groups of people.
The groups included forest owners, high school teachers, high school students, senior citizens, and a fifth group - ?o he ? - consisting of people of mixed ages and backgrounds.
Förröjning i förstagalling - vad kostar det och följer utförarna instruktionerna?
This report is a B.Sc. Forestry thesis work at the school for Forest Management, SLU.
The work was an assignment from the forest owners? association Mellanskog.
The aim of the work where to investigate the economical result of removing undergrowth trees before first thinning, and a follow-up of the contractors and their compliance with Mellanskog standards.
This thesis work was divided in three parts: The first was to find a relation between the net volume from the first thinning and the cost of cleaning undergrowth trees. Secondly there was a follow-up in the field, to investigate whether the contractors have done the undergrowth cleaning according to Mellanskog?s directives.
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.
Ett land som inget annat : Bilden av Sydafrika före, under och efter en utbytestermin i Stellenbosch
The mental constructions of other places are based on impressions from everything that surrounds us in our everyday life, e.g. pictures, videos, texts and narratives. The tourism industry is especially influential when it comes to creating the image of before ?unknown places?. Furthermore, it has a tendency to embellish and idealize people and places located in what is commonly known as the Third World.