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491 Uppsatser om Dead trees - Sida 29 av 33

Från gles skog och brokiga ungskogar till homogen produktionsskog : en skogshistorisk studie av Hällforsmarken under 1900-talet

The forest in the northern part of Sweden has changed dramatically during the last centuries. The forest has gone through a large-scale transformation, from it being only used locally for domestic purposes to becoming very important raw material for Sweden in the industrial age. The strategy by foresters during the second half of the 20th century has been to create pure production forests for commercial forestry. This has mainly succeeded and we have today homogenous production forests that give a high profit to the owners. The aim of the study is to compare the state of the forest in the former state forest Hällforsmarken in the years 1925 and 2000 and to interpret the changes which has taken place.

Site preparation, planting position and planting stock effects on long-term survival, growth and stem form properties of Pinus contorta on southern Iceland

In order to evaluate different afforestation methods for exposed heath lands a field experiment was established in Mosfell on southern Iceland in 1989. The trial comprised six different site preparation methods (control, herbicide application, tree shelters, patch scarification, TTS trenching and mounding). In total 960 container seedlings (1+0) and 960 Nisula roll transplants (2+1) of lodgepole pine were planted. Various planting positions (furrow, hinge, no site preparation (control) and on top of mounds) were tested within the site preparation treatments. This study involves renewed measurements and analyses of the trial.After 19 years the overall survival was 51,7 %.

Kan man genom kartstudier förutse häckningsframgång för ängshök (Circus pygargus) i Uppland? :

Montagu´s harrier (Circus pygargus) is a diurnal, Eurasian raptor, which migrates from its northern breeding grounds to winter in sub-Saharan Africa. In Sweden, its core breeding area is centred on the island of Öland, with a stable breeding population of approximately 40 pairs. The province of Uppland is on the northern end the distribution range, where 4-8 pairs have regularly bred since the 1980s. In Sweden, the Montagu?s harrier is classified as an endangered (EN) species. This classification is partly due to a lack of preferred nesting habitat, such as shrub-lands or dense wetlands with Claudium spp.

Gångvägsljus :

Discussing light and lighting in the night-time environment of Tensta, a Stockholm suburb built between 1962 and 1970, this thesis suggests that lighting should be designed for the outdoor environment as a whole. The feeling of safety and human perception are important components in this thesis. Starting with some comments on visual perception and how we adapt our sight to an interval of the visual input we get, makes it possible to understand that more light sometimes hides, rather than reveals, things. Amongst the dispersed houses, in the green parks of Tensta, this turns the pedestrian roads, lit by pole-top-mounted fixtures, into light tunnels in a dark surrounding. Talking about the feeling of safety I am inspired by, amongst others K. Lynch, B. Hjort and J.

Utveckling av en dynamisk Simuleringsmodell av en skotare

The predominant forestry harvesting method is based on the harvester-forwarder method, theharvester folds, branches and cuts trees, and sorts the logs into piles, while a forwarder transportsthe logs to a landing area.This master thesis work is about realization of a dynamic forwarder simulation model, and itspurpose is to provide an integrated forwarder simulation model in MATLAB/SimMechanicswhere the forwarder is based on a concept using pendulum arms to connect wheels and chassis.Active suspension control is developed and implemented into the simulation model, and finallycompared in simulation with passive suspension.In a first step, an integrated forwarder simulation model is developed, containing a simplifiedforwarder model, a tire-to-ground interaction model and a test track model. The simplifiedforwarder model is based a rigid multi-body system with a spring-damper suspension of thependulum arms. The tire-to-ground interaction model calculates the reaction forces, friction fromthe ground and applies the propulsion force. The test track model is a simplified version of thereal test track in Skogforsk. The propulsion wheel torque control is used to regulate theforwarder speed.

Mänsklig påverkan på mindre vattendrag i skogslandskapet : en inventering av vägtrummor och skyddszoner kring dessa i Uppsala län och norra Västmanlands län

Interference in an ecosystem means a disturbance. When harvesting, forest roads have to be build to cope with heavy duty vehicles. Crossing brooks can not always be avoided. In this case bridges or culverts have to be built. There are many different kinds of culverts and depending on what type you choose and how you place the culvert, the watercourse and the water organisms can be harmed in different ways.

Spår av autism i Czeslaw Milosz Issadalen - Traces of Autism in Czeslaw Milosz Valley of Issa

The partly autobiographical book Valley of Issa, written by Czeslaw Milosz describes (among other things) the childhood of a boy, Tomasz who is the main character, and his interactions with his relatives. In this essay I will claim that these characters possess startlingly obvious autistic traits, and in relation with this I raise and discuss another question: Does the author Milosz himself express autistic traits? My essay could hardly constitute a complete analysis with definite answers, (the bachelor format of the essay and the fact that Milosz is dead limits more extensive investigations) and I do not mean to claim that Milosz was a sick person, even though I may suspect it. Let this essay be an eye-opener and a visionary foundation for new approaches to Milosz authorship. The value of it lies in its approach.

Mekanisk integration av en IR-detektor i en Stirlingkylare

The master thesis ?Mechanical Integration of an IR-detector in a Micro Cooler? has beenperformed at FLIR Systems AB in Danderyd. FLIR Systems is a world leader in the design,manufacture and marketing of thermal imaging camera systems.The thesis project is divided into to two areas, Production Method and Noise.The Production Method concerns the positioning of a detector on the cold finger within the IRcamera.The detector has to be positiond with very high accuracy at the center of the cold finger,so it can be placed in line with the optical axis to avoid movement of the picture during zooming.The positioning of the detector is at present done with the help of specially designed guides on aplate on top of the cold finger. The design workes well but the special machining needed for thisplate is very expensive.The goal concerning the production method was to derive a new more cost effective method forthe assembling and positioning of the detector on the cold finger by replacing the guides on theplate with a reusable equipment or some other alignement operation.Several concept ideas have been generated with the help of concept generation methods in theform of concept classification trees and concept combinational tables. Two of these conceptswere selected to be further refined.

Precommercial thinning stumps´susceptibility to Heterobasidion spp : a comparison between high and low Norway spruce and birch stumps : a measuring of the efficacy of Phlebiopsis gigantea stump treatment

Each year, Heterobasidion spp. is a major cause of economic losses to forestry in the northernhemisphere, including Sweden. New results indicate that pre?commercial thinnings could be at riskfor Heterobasidion spp. infections.

Analys av individinriktad ekskogsskötsel i Blekinge : en metod för tillämpning i ett kontinuitetsskogsbruk?

Ett ökat brukande av skog enligt skötselprinciper som leder till skiktade beståndsstrukturer, en blandad trädslagssammansättning och kontinuerligt skogbeklädd mark har potential att öka den biologiska mångfalden och värdet för rekreation (Emborg m.fl. 2000, Berg m.fl. 1995, Mattsson & Li 1994, Holgen m.fl. 2000). I ljuset av detta, tillsammans med svårigheterna som finns att nå goda ekonomiska resultat vid skötsel av ädellövskog (Lindén & Ekö 2002), ses det idag som angeläget att uppmärksamma och studera alternativa skogsskötselmetoder (Cedergren 2008) . I östra Blekinge har ett antal skogsägare under längre tid praktiserat en metod att sköta naturligt föryngrad ek i blandbestånd som går ut på att, mer eller mindre tidigt, frihugga ekhuvudstammar, och att dana kvalitet genom stamkvistning/beskärning.

Management factors influencing sow productivity in successful Swedish and Danish herds

The number of weaned piglets per sow and year is a good measurement of sow productivity since it is affected by the number of piglets born alive, the pre weaning mortality (i.e. mortality of live born piglets between birth and weaning) and the number of litters per sow and year. This measure is also closely connected to the number of piglets produced per year, which partly determines the profitability of the piglet producer. During this study, eleven successful piglet-producing herds were visited. Eight of the producers were Swedish and three of the producers were Danish.

Gallringsinventering från helikopter utrustad med profilerande laser och kamera för låghöjdsfotografering

Today Holmen Skog finds and selects suitable thinning stands using data on upper height and basal area. These figures are often based on basic forest data that has been updated with the help of growth prediction models. The problem is that these figures are not always correct. The aim of this study was to investigate if a combination of data from a profiling laser and a digital camera for low elevation photography, can be used for collecting data on number of stems per ha, tree species mixture as well as basal area weighted mean height and upper height for stands. The possibility to use these data to assess the need for thinning cutting was also investigated.Laser data and aerial photographs were collected from a helicopter operating at an approximate height of 100 meters.

Träd och buskar i kantzoner : en undersökning av kanteffekter i några av östersjöregionens skogar

Around the world, forests are generally being fragmented and as plant populations decline in both sizeand number of individuals, the genetic variation will also decrease whitch in the end leads to totalextinction of the plant. In this paper, I wanted to investigate what specific species of trees and shrubsyou usually find in the edge and core habitats in some of the forests in the Baltic Sea region. I alsowanted to identify the edge effects and their sources and finally compare the results between thedifferent regions.The data sources used are derived from the ongoining research project Landscape structures, patterns ofbiodiversity and conservation strategies in the Baltic Sea region by Kari Lehtilä, Patrik Dinnétz ochTiina Vinter who have made a record of all herbaceous plant species in four randomly chosen forestregions situated around the Baltic Sea: Estonia, Skåne, Södermanland and Germany. I made statisticalanalyses, using the computer program R, concerning the distribution of species in the edge habitats ofthe forests as well as in the core habitats. I performed generalized linear models and then variationanalyses with the factors light and biomass in order to investigate wether edge effects might appear dueto these factors.

S:t Sigfrids granne : en begravningsplats för alla

This paper is about cemetaries in a multireligious society. The aim of the work is to compare the physical expressions of different religions burial traditions, in order to plan a multireligious cemetary in Borås. I´ve studied the five worldreligions, Judaism, Chritstianity, Islam, Buddhism and Hinduism. I´ve also written about the Humanism, a nonreligious organization, and funerals without any religious connection. Litterature studies gave basic knowledge about the religions beliefs, and interviews with a person from each group deepend the knowledge, mainly regarding the burial traditions.

Om eleverna själva får välja : En studie av högstadieelevers attityder till litteraturläsning

This essay examines the decline of reading comprehension in Swedish schools, and also aims to provide insight into the debate concerning a literary canon and its usage in schools. While some claim that the literary canon is only a list of irrelevant white dead men which only serves to perpetuate feelings of alienation in, for example, female students, others see it as a means to bring society together using the only literature that stood the test of time. This essay will look to studies concerning reading comprehension, and questions regarding reading habits which our own students answered. It will also explain the different viewpoints of both sides of the canon debate.There are several studies that show this decline in reading comprehension, PISA and PIRLS being the foremost of them. They point to a trend where the reading skills of boys are much worse than those of girls, a trend which still has not panned out.Bloom and the different researchers who are the basis for Verhaest's thesis are of the opinion that canonical literature serves a purpose in that it teaches students aesthetic literary values.

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