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491 Uppsatser om Dead trees - Sida 9 av 33

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.

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.

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.

Naturvårdande skötsel (NS) - blir resultatet som man tänkt sig? : en fältstudie över föryngring, trädslagsfördelning och död ved 14 år efter åtgärd

A new Swedish political approach to forestry was initiated 1993, that put goals of production and environmental issues into equal importance to Swedish Forestry Law. Earlier nature conservation very often declaimed preservation the best way to conserve nature, but recently it is clear that many highly biological values are due to former land use or disturbance. Many old pastures or cultivations dominated by deciduous trees are today characterized by a dense overgrowth of Norway spruce. By actively paying attention to nature in forestry (nature restoration), it is possible to partly reconstruct habitats or disturbances that are necessary to favour the biological values. The aim with this master thesis is to study the nature restoration, (NS, Swedish abbreviation), performed in 11 forest sites in the middle of Sweden 8-14 years ago. Since NS recently have become applied, it has never yet been evaluated.

Metoder för att undersöka effekterna av naturvårdshänsynen i skogsbruket efter den nya skogsvårdslagen

Detta arbete har undersökt skillnaderna mellan den nuvarande skogsvårdslagen och den föregående. Undersökningen har bestått av två delar, där ena delen är en litteraturstudie av lagarna och den andra är en fältstudie av metoder för att mäta naturhänsynsförändring. Som komplement till fältstudien har en litteraturstudie av undersökningsparametranas naturvårdsnytta. Litteraturstudien av lagarna gick till på följande sätt, inledningen av båda lagarna och hänsynsparagraferna har lästs och jämförts. Fältstudie har gjorts efter metoder som har arbetats fram och sedan testats i fält.

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.

Orientering av liv och död under Mellanneolitikum. : Irland, Orkneyöarna och södra England under perioden ca 4000 f.kr ? 2000 f.kr

Tovesson. R 2012: Orientering av liv och död under mellanneolitikum. Irland, Orkneyöarna och södra England under perioden ca 4000 f.kr ? 2000 f.kr.The orientation of life and death- Ireland, Orkney, and Southern England during c 4000-2000 BC.Magisteruppsats i arkeologi. Linnéuniversitetet Kalmar Vt.

Föryngring i stormfälld rekreationsskog : en jämförelse mellan föryngring i produktions-, rekreation/produktion och rekreationsskog.

When the storm Gudrun hit Sweden on the 8th and 9th of January, many recreational forests in southern Sweden blew down. For this reason there is a demand for new regeneration methods as to how these storm-felled areas should be regenerated and with what species. In this study the forest is divided into three areas: production, recreation/production and recreation. The first area is a forest with production as main goal and these kinds of forests are located a bit from the city. The second type ? recreation/production forest ? has two equal goals: production and recreation, and is located close to the city.

Betesskador på lärkplantor

The purpose of this study was to show how the Hybrid Larch (Larix eurolepis x) are used by large herbivores in terms of grazing and fraying. More specifically I studied how impact on the seedlings was affected by forest stand area, tree height and stem density (stems/ha).The survey was done in Jönköpings county in southern Sweden. About 50 % of all stems that are measured are damaged by grazing and 5,8 % was damaged from fraying. The conclusion of the study is that the biggest influencing factor is the height of the seedlings. The size of the stands and number off seedlings per hectare have almost no impact on the injuries on the seedlings. Fraying are common on trees smaller than 3 meters, and doesn?t occur on trees above that height.

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.

Skillnader i mulmvolymer mellan fem trädslag i Östergötlands eklandskap

Old hollow trees of oak contain a large amount of wood mould. Unfortunately, these trees have in the last century been greatly reduced in numbers. It has resulted in that species that depend on these habitats, saproxylic species, have become at risk to decrease in numbers or die out regionally. Previous studies have shown that the volume of wood mould is an important factor for occurrence and population size of saproxylic organisms. The aim of the present study was to examine how the volume of wood mould varies among ash (Fraxinus excelsior), lime (Tilia sp.), maple (Acer platanoides), aspen (Populus tremula) and oak (Quercus robur).

Fruktkvalitet inom äppelodlingen : en studie av och för Äppelriket Österlen

The main purpose of this Master Thesis has been to investigate issues concerning apple fruit quality in orchards of Äppelriket Österlen. The goal has been to develop a document, for future benefit towards growers and company management in the production of high quality apples.In order to investigate main issues of fruit quality, focus has been on statistics concerning apple varieties, age of the apple trees, new planting, orchard size and growers opinions. Nine growers have been interviewed to investigate opinions and contribution of different growing techniques to increased fruit quality. The investigation showed high age of the trees in production and low rate of planting of new trees. Differences in fruit quality were highest between small orchards. Most growers were satisfied with their fruit quality and with their own measures made to improve it.

Stem injection of different nitrogen forms into young Norway spruce

This master thesis has been a pilot study preceding a forthcoming project of a larger scale with the long term objective to separate the direct effect of added nitrogen on soil processes from indirect effects via trees. The aim of this study has been to investigate the allocation of nitrogen following direct injection of liquid solutions into the xylem of 40 year old Norway spruce. The field site is located at Flakaliden (64°07?N, 19°27?E), approximately 60 km northwest of Umeå, Sweden. A total of 18 trees were selected for treatment, equally divided between three treatments, potassium nitrate, glutamine and water (control).

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