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286 Uppsatser om Hub height - Sida 4 av 20

The effects of Gotland pony grazing on forest composition and structure in Lojsta hed, south eastern Sweden

Livestock animals affect their environment in a number of different ways, mostly through grazing and trampling. This study focused on the effects of Gotland pony grazing on forest structure and diversity, and the impact on ground cover. To compare the fenced and grazed area with a reference area outside the enclosure a number of transects were used. The study showed that there was no significant difference in height structure and diversity between the compared sites; however, there were a significantly higher proportion of damaged trees inside the enclosure. The ground cover variables showed a higher amount of bare soil, plant litter and wood-rush (Luzula sp.) inside the enclosure whilst grass was more frequent in the reference area.

Skattningar i gallringsskog med hjälp av flygburen laserskanning : beräkningar med massaslutenhet

This master?s thesis is a remote sensing study of an area-based method used to detect forest in need of thinning by use of laser data and field samples. Only pine-dominated forest has been included in the study and height limits were set to match empirical restrictions. The study area was in the municipality of Älvsbyn (Latitude 65° 40´ N, Longitude 21° 00´ E), in northern Sweden.The Swedish authority Lantmäteriet is currently laser scanning most parts of Sweden, providing new opportunities and applications. The primary aim of the national laser scanning is to create a new elevation model, useful in consequence analysis of climate changes.

Analys av data från flyglaserscanning :

In forestry there are always needs of forest data to make good strategic decisions of different actions and economic winning. Usually this data gets from field-estimations made by forest workers with expensive costs and sometimes unsatisfied quality. StoraEnso Skog is a great forest company in Sweden and they have part of the responsibility of the forest own by Bergvik Skog. Bergvik Skog is owner of 1, 9 million hectares productive forest land. Both Bergvik and StoraEnso have great interest in new inventory techniques to get the important forest data. The company Foran Remote Sensing offers the opportunity with airborne laserscanning of forest and forest land. Foran got the mission of Bergvik and StoraEnso to laser scan Bergviks possession in Älvdalen, Dalarna.

En undersökning av Bergvik skogs och Skogsstyrelsens gallringsmallar mot en gallringsoptimering på simulerade typbestånd

The purpose of this study was to analyze the two thinning models: Bergvik Skog´s thinning model, which is based on total stems and dominant height, And Swedish forest agency´s thinning model which is based on basal area, habitat index, dominant height and recommended number of stems at final felling in Heureka´s StandWise and PlanWise. The data we chosen for our study were taken from the Swedish National Forest Inventory and we were creating a simulated stand based on a great number of sample plots in Region three from The Swedish National Forest Inventory. We had chosen to create one stand with low habitat index (T20) and one with high habitat index (T24). Our purpose were to come as close as possible to a natural stand in central Sweden. We performed the thinning in StandWise and analyzed the data I Excel files. Our thinning optimizing´s were performed and analyzed in PlanWise. There wasn´t any big differences between the thinning on the lower habitat index.

Productivity of Norway spruce (Picea abies) and Scots pine (Pinus sylvestris) in coastal areas of northern Sweden

Productivity of Norway spruce (Picea abies) and Scots pine (Pinus sylvestris) was studied on 12 sites in coastal areas of northern Sweden. On each site, sample plots were placed in adjacent Norway spruce and Scots pine stands with similar ages in between. Basal area, tree height, Site Index, volume production, simulated maximum mean annual increment (MAImax) and tree vitality were compared for the two species. Average basal area at the time of measurement was 30.4% larger for Scots pine stands than for Norway spruce stands. The difference between the two species in basal area increment during the last 10 years was related to stand age.

Optimering av påstorkning : Från behov till färdig konstruktion

This thesis describes the redesign ofequipment designed for drying bags thatis used in Fresenius Kabis´manufacturing of their nutritionmedicine in Uppsala. The need of thistask arise during the start of thedevelopment of a new packaging line werethis equipment were meant to be used. Anevaluation of the bagdryers capacity andcapability was necessary.The work started with gathering ofinformation from suppliers of the usedcomponents and from the responsibleengineers for this equipment. Aneducation to learn how the equipmentworked and how to operate it were taken.That was followed by the creation of astudy plan were the tests were plannedto test different parameters effect onthe drying result and to see if thebagdryer managed to handle the bags ofthe correct format in the pace that theequipment should be designed for.The test results detected a need ofdesigning a unit with a function thatholds the bags in place while passingthrough the dryer in order to attainhigh quality results. The results werelater used for optimization of thedesign.

Utveckling av instyrningsfunktionen hos ett dockningsinterface

In this project the task has been to develop a product that will facilitate an operation for personnel working in a sterilization center. The operation is to steer the front of a loading trolley into the chamber of an autoclave, a so-called docking. The moment is complicated because the margins to deviate from ideal docking position and still succeed, is very small.The principal Getinge's desire was that the product could be retrofitted at the customers on their existing systems. One of the demands was that the product should fit two types of trolleys, one with a adjustable working height and one with a fixed working height. Getinge is supposed to purchase the system from a subcontractor who shall manufacture it and the requirement from Getinge is that the cost of purchase mustn't exceed SEK 500Initially principles, solving the problem was developed.

Picea mariana ((P. Mill.) B.P.S), P. abies (L.), Pinus contorta (Dougl.) och P. sylvestris (L.) : en jämförelse av produktion och potentiell kvalitet hos försöksbestånd i Jämtlands län

Swedish forests are dominated by just two conifer species Norway spruce and Scotch pine. They are not able to achieve the highest possible production or fulfill industry demands for raw materials. The introduction of exotic conifers can potentially meet these shortcomings and present a relevant solution. This study was conducted in a block experiment with ten blocks planted in 1987 by SCA in North Sweden. The objective of the block experiment was to study if Black spruce is an appropriate alternative to Lodgepole pine, Norway spruce and Scotch pine on different site classes.

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.

Testikelmått och daglig spermieproduktion hos svenska halvblodshingstar :

Testicular measurements and daily sperm output (DSO) are important factors affecting reproductive capacity of stallions. In the present study testicular measurements of 10 Swedish half-blood stallions were determined (height, length, width and volume). Ejaculates were collected from each stallion once daily for 10 days to evaluate some important seminal characteristics: gel-free ejaculate volume, sperm concentration, percent progressively motile spermatozoa and total number of spermatozoa (TSN). The gel-free ejaculate volume was measured with a graduated cylinder, the sperm concentration was counted in a Bürker chamber, the sperm motility was estimated in a phase-contrast microscope and TSN was determined by multiplying the gel-free seminal volume by the sperm concentration. Testicular measurements were as follows (left and right testis): height 7,5 cm and 7,8 cm, length 10,6 cm and 10,8 cm, width 6,5 cm and 6,6 cm, volume 278,2 cm3 and 293,8 cm3, scrotal width 12,3 cm and total testicular volume 572,0 cm3 .

Hyggesbränning på Orsa besparingsskog - en studie på tillväxt och föryngring,15år efter etablering

The main purpose with this study was to investigate whether the tree growth differs or not in prescribed burnt areas compared to mechanically scarified. Together with the result from the main purpose, answers of whether it's possible or not to combine nature conservation with tree production in prescribed burnt areas was presented. In these areas the regeneration were analyzed to see if there was enough tree plants to comply with the Swedish Forestry Act regulations terms for approved regeneration. A field survey was conducted at 6 objects, three objects for prescribed burning and three for mechanically scarification. All objects were planted within the same year.

Geoteknisk bärförmåga hos borrade injekterade pålar i åsmaterial Fältförsök: Slussen i Stockholm

This thesis describes the redesign ofequipment designed for drying bags thatis used in Fresenius Kabis´manufacturing of their nutritionmedicine in Uppsala. The need of thistask arise during the start of thedevelopment of a new packaging line werethis equipment were meant to be used. Anevaluation of the bagdryers capacity andcapability was necessary.The work started with gathering ofinformation from suppliers of the usedcomponents and from the responsibleengineers for this equipment. Aneducation to learn how the equipmentworked and how to operate it were taken.That was followed by the creation of astudy plan were the tests were plannedto test different parameters effect onthe drying result and to see if thebagdryer managed to handle the bags ofthe correct format in the pace that theequipment should be designed for.The test results detected a need ofdesigning a unit with a function thatholds the bags in place while passingthrough the dryer in order to attainhigh quality results. The results werelater used for optimization of thedesign.

Utvärdering av flygbildstolkning för uppskattning av beståndsvariabler och åtgärdsförslag i ungskogar : en studie på Korsnäs Skog och Bergvik Skog AB i västra Dalarna

In Korsnäs district Dala Väst there were problems with information concerning their younger forests, mainly those in pre-thinning stage. They were divided into large, heterogeneous stands with often poor stand data quality. In 2006 an aerial photo interpretation of the young forests was conducted to fix these problems. Necessary information to get from the interpretation were silvicultural management suggestions, new stand delineation and new stand data. This thesis is supposed to evaluate the quality and usability of the interpreted data. To evaluate the interpretation an objective control inventory was conducted in 60 stands, either through callipering or counting stems.

Fodersammansättningens betydelse för tillväxt hos häst :

The aim of the present study was to investigate the effect on growth of foals on two different diets, either a forage-based diet or a diet containing approx. 40 % concentrate. The report also includes a review of the pertinent literature on the effects of diet on mares? milk and growth of horses. The hypothesis of the study was that a forage based diet will result in a similar growth pattern as a diet including more concentrates if the diets contain the same amount of energy, crude protein, lysine, calcium and phosphorous.

Höjdförändringar på Lomonosovfonna, Svalbard, 1996-2012

The climate changes and the global warming have a great impact on the Arctic environments. This partially depends on that the albedo is getting lower when snow and ice is melting and exposes more and more dark surfaces of the land and sea. This leads to a feedback effect; the melting accelerates because dark surfaces attract more sun radiation. Because of the heating the glaciers in Arctic retreat. The purpose of this report is to obtain an eventual change in elevation on the glacier Lomonosovfonna that is located on Svalbard by comparing elevation data collected by NASA and GPS data from 1996-2012.

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