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957 Uppsatser om Tropical rain forest - Sida 31 av 64

Vedlevande lavar på döda grenar på levande träd i produktionsskog

Saproxylic lichens in managed forests have less substrate available than in unmanaged forests due to the shortage of dead wood. However, a suitable substrate for these lichens could be dead branches on living trees. To this date, there has not been any systematically collected data about theabundance of dead branches on living trees and the lichens growing on these branches in managed forests. The aim of this study was to see where dead branches were located on living trees of Pinus sylvestris and Picea abies, how large the surface area of these branches was and what lichens grewof wood on these branches. The study was made in Finspång, Sweden, where 11 forest stands of P.sylvestris and P.

The distribution of Moose (Alces alces) during winter in southern Sweden : a response to food sources?

The traditional Swedish way of dealing with browsing damages made by moose, is to reduce the moose population. However, a growing way of dealing with damages made by several ungulate species, including wild boars in particular is to redistribute them with supplementary food sources. Attracting them to settle in habitats less vulnerable to damages made during foraging. This study we tracked collared moose in southern Sweden from January throughout April in the year of 2009. From the tracking data their ?favourite? positions was selected and visited in order to study the features that attracts moose during winter.

Do grizzly bears use or avoid wellsites in west-central Alberta, Canada?

The purpose of this report is to make an evaluation of the self-monitoring for scarification which Stora Enso is using and this study deals with the effects and importance of scarification. A comparison is made in this study with the purpose to highlight any differences between some of the leading forestry companies and significant forest organizations in Sweden. The companies represented in this report are Korsnäs, Mellanskog, SCA, Sveaskog and Södra. In the beginning of this study an interview form was set up together with Daniel Forsberg at Stora Enso. Stora Enso is the head object of this report and seven interviews were made within that company. At the other companies only three interviews were made within each one, with an exception to Mellanskog who wished four.

Skogsentreprenadföretagens lönsamhet :

During some time there has been a debate whether or not logging contractors? profitability can be considered poor. The contractors? situation is important for maintaining long term relationships and continuity in the forest industry. A thorough analytic picture is however missing.

Generationsskiften i familjejordbruk : genomförande och familjerelationer

Within the next five years about 15 % of the Swedish forest owners that will undergo a succession of ownership. Presently the most common way to acquire a forest estate in Sweden is to acquire it within the family. To decide to let go after a whole life as a forest owner and manager of your own land is for many people a hard decision to make and often requires a long process. The complex process that a succession of ownership often is includes both questions about economy, legal aspects and regulations, taxes and questions of more personal nature, often called soft issues. These personal aspects or soft issues are important and can if handled poorly or not at all negatively affect relationships in the family for a very long time.

Död ved i gallrad skog och nyckelbiotoper : en jämförelse av habitatkvaliteter för vedlevande lavar och mossor

A high amount of dead wood is one of the most important prerequisites for high biodiversity on forest land in Sweden. Dead wood is most abundant in young forests, thinned forests, woodland key habitats and protected forest land. In old-growth forests most of the dead wood consists of logs and snags, whilst in managed forests a huge proportion of dead wood is made up of logging residues like stumps and FWD, fine woody debris (< 10 cm diameter). All these different types of dead wood may serve as substrates for epixylic bryophytes and lichens. However, few studies have been conducted on the relative importance of these different fractions of dead wood for the occurrence of bryophytes and lichens, especially when considering dead wood on thinned forest land.

Fuktskador i ytterväggar på grund av vattenintrång

Moisture damage in buildings is a serious issue that leads to problematic consequences and high economic costs. Despite the knowledge and awareness existing about moisture problems, extensive damager still occurs today. Studies of moisture in the exterior wall constructions shows that the issue if often caused by rain and water intrusion. These kinds of problem result in major costs usually because the companies have to replace the material and structural components and also in some cases tear down large parts of the buildings.The work includes moisture theory and descriptions of four different exterior wall constructions, wood stud wall with plastered facade, exterior wall with wood facade, exterior wall with concrete, and exterior wall with brick facade. Our thesis work describes how the constructions are affected and moisture damage due to water intrusion.

Barns tankar om vattnets kretslopp och vattnets betydelse för livet på jorden.

Huvudsyftet var att ta reda på vad förskolebarn kan och tänker kring vattnets kretslopp och vattnets betydelse för allt liv på jorden. Samtidigt syftade undersökningen till att ta reda på pedagogernas arbetssätt och tankar kring dem. Undersökningen har genomförts med hjälp av kvalitativa intervjuer med såväl pedagoger som barn. Intervjuerna har spelats in och sedan transkribetats för att därefter analyseras. Resultatet av undersökningen visar att barnen har god kännedom om vattnets kretslopp och vattnets betydelse för livet på jorden.

Minskad utbredning av apollofjäril, Parnassius apollo, i södra Stockholms län : En studie av möjliga faktorer utifrån artens habitatkrav

The Apollo butterfly, Parnassius apollo, is categorized as Near Threatened (NT) in IUCN Red List. Today in Sweden it is found only in strongly fragmentized populations. In the county of Stockholm, P. apollo exists exclusively in some islands of the archipelago and with one mainland population in Stora Vika. This study has the purpose of expanding the knowledge of the local conditions for the butterfly in the south parts of the county of Stockholm and thereby contributes to a sustainable land management that can preserve the Apollo butterfly.A comparative study was done between areas where the butterfly today have: a stable population (Stora Vika, Utö and Ålö), has disappeared (Muskö and Yxlö) or is strongly declining (north part of Ornö).

Den skogliga informationens roll i ett kundanpassat virkesflöde : en bakgrundsstudie samt simulering av inventeringsmetoders inverkan på noggrannhet i leveransprognoser till sågverk

This MSc thesis is divided into two parts. The first part deals with the need for information from forest campartments selected for clear cutting, in connection with planning in an integrated forest- and sawmill enterprise. A review of literature is followed by a case stud y, where present conditions in a Swedish forest company are compared with current research in the area. The seeond part consists of a simulation stud y, which aims at camparing the accuracy of inventory estimates using different methods. The estimates are delivery forecasts, covering one month consumptian of timber in a large sawmill.

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.

Öppen dagvattenhantering i urbana miljöer :

Storm water causes a number of problems in our country, particularly in city environment with its surfaces of non-absorbing ground materials. At heavy rain falls there are floods due to lack of capacity in the drain system when meeting heavy water masses over a short time. When the drain system is overloaded huge water masses reach the recipient untreated and there causing disturbances in the aquatic ecosystem. Due to emissions from mainly traffic, industries and other human activities the storm water is polluted. Earlier the problem used to be solved technically, by increasing the capacity of the tubes and by construction of reservoirs to delay the floods peaks.

Däck-mark Interaktion hos skogsmaskiner

The most predominant method for forest harvesting in Sweden is the cut-to-length method based on two-machines, a harvester that fells trees and cut them in a predefined length, and a forwarder which transports logs to a landing area for further transport to a processing facility. New machine solutions have to be much gentler to the ground than today?s machines. To be able to develop a forestry machine that preserves the terrain requires a proper understanding of the interaction between tire and soil.The goal of the project is to contribute to the existing knowledge of forest machine tire-soil interaction and to develop a tire-soil model that enables dynamic simulations of forest machines operating in rough terrain. The modeling has especially been focused on the interaction between tires and soft ground.A comparison of theoretical data of different WES-based terrain interaction models and a comparison test data from a full scale field test is presented.

Att veta Gudarnas hemlighet : En sårbarhetsanalys av omständigheterna kring stormen Gudrun med pressure and release modellen

The concept of vulnerability is the capacity or the sensitivity to become damaged. Vulnerability are characterized by one or more of the following terms; a system´s sensitivity to exposure to shock, stress or interference, the state of the system in relations to a threshold of damages, and the system´s ability to adapt to the changing circumstances. Vulnerability in this study is referring to the sensitivity of the circumstances that lead to sustainable livelihood that can´t be maintain and that there is an inability to cope with and manage stress. The choice of making a study in this area is based on that action needs to be taken to moderate the vulnerable aspects of society, in this respect in relations to storms. Analyzes of the social vulnerability to climate change or natural events is needed for effective actions.

Vad orsakar skador på kvarstående träd vid mekaniserad gallring - en intervjustudie

This thesis includes a review of scientific studies of tree injuries following mechanized thinning. Interviews have been made with drivers of single grip harvesters and forwarders in forest thinning and a number of essential factors have been identified as the most important to take into account in order to minimize and/orprevent injuries to stems and roots of remaining trees..

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