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285 Uppsatser om Hub height - Sida 2 av 19

Tillväxt och potentiell sågtimmerkvalitet i gallringsmogna jämförelseplanteringar med Pinus contorta och P. sylvestris :

The Swedish Cellulosa Companiy, SCA, has today 280 000 ha planted with lodgepole pine (Pinus contorta var. latifolia) (?C?) which is equivalent to 14 % of its total forest area. Exotic lodgepole pine has in previous experimental stands shown a superior growth than the native Scots pine (Pinus sylvestris L.) (?S?).But also the comparison could be questioned because stand histories were was unknown and also differences in age between C and S existed.

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 %.

Behavioral studies in healthy Standardbred trotters subjected to short term forced recumbency aiming at an adjunctive treatment in an acute attack of laminitis

Laminitis is a debilitating disease causing much suffering to horses and ponies all over the world. It is manifested in the hooves as a mechanical failure of the suspensory apparatus between the hoof capsule and the distal phalanx. Due to the weight of the horse the disease may result in a dislocation of third phalanx. Six healthy standardbred trotters were used in this study on whether standardbreds tolerate forced recumbency as well as Shetland ponies. Recumbency was induced pharmacologically but maintained only by lowering the ceiling height of the box to a height of approximately 125 ? 140 % of the horse´s thoracic height.

Levande vikt vid olika åldrar och sambandet med bröstomfång och mankhöjd hos SRB och SLB :

Live-weight at different ages for Swedish Holsteins (SLB) and for the Swedish Red and White Breed (SRB), and the correlation to heart girth and height at withers. The aim of this investigation was to study the live-weight changes and mature weight for the Swedish Red and White Breed (SRB) and for Swedish Holsteins (SLB), and to estimate the correlations between body weight and body measurements such as heart girth and height at withers, respectively. The material used was from one of the experimental dairy herds (Jälla) of the Swedish University of Agricultural Science. It included recordings on 293 dairy cows with information from 7142 weight occasions and recordings on 275 dairy cows with information of 557 heart girth measurements and 560 measurements of height at withers. The registrations were done during 1993-2002. There was a large variation in live weight between cows in different ages and lactation stages.

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.

Fågelbär (Prunus avium L.) - överlevnad, höjdutveckling och skador i unga planteringar på småländska höglandet :

Plant survival, plant damage and height growth were studied in nine wild cherry (Prunus avium L.) plantations in southern Sweden established between 2000 and 2002. All stands were located to the county of Småland. The survey was conducted during May and June in 2007. During the survey the height, diameter and quality of the cherry trees were recorded. In one stand, red ? berried Elder (Sambucus racemosa L.) was a dominant species.

Ajuourhållning av ungskogsdata med hjälp av digitala flygbilder :

The purpose of this study is to investigate whether it is possible for SCA to update their stand register with use of digital aerial photos photographed with a Zeiss/Intergraph DMC. ?Updating? in this study implies the delineation of stands and estimating stand variables such as average stand height, volume density, stand volume, and tree species composition in order to identify stands which can be of current interest for thinning. The study also includes how the aerial photo material and experience of the interpreter can influence the quality of the interpreted variables. The aerial photo interpretations were made by both experienced and inexperienced interpreters.

Förtolkning inför skogsbruksplanläggning med laserdata (NNH), eller traditionell flygbildstolkning?

The purpose of this study was to investigate produced laser data from the new national height model's airborne laser scanning in Sweden, what quality it has and whether it can be used for forest management planning. From airborne laser scanning one can obtain information on forest variables such as tree species, height, diameter and basal area. Norra skogsägarna is the principal employer of this project and they wanted know to the quality of the laser data which needs to cope with their standards. If the laser data the quality required it can replace some of the operations performed by field planners. To examine the quality of the produced laser data a control tax assessment has been performed in 30 forest departments. This was done in an objective manner.

CFD simulering av kallras : Undersökning av temperatur- och luftbeteende intill höga glasfasader och i vistelsezon med golvvärme som en värmekälla

Glass has sophisticated front properties and are used as facades in high buildings. During cold periods, these glass facades could cause thermal discomfort, due to cold downdraught. Cold downdraught can be countered by placing heaters under glass surfaces. Nowadays technology offers highly insulating windows, which is why there is an interest to investigate the indoor climate with only underfloor heating. The research in this area is limited, and few empirical methods are available.

Höjdtillväxt, överlevnad och skador i praktiska etableringar av hybridaspbestånd i södra Norrland, anlagda 2004-2011

Hybrid aspen is a crossbreed between European and North American aspen. It is a fast growing tree species that has shown strong growth in the South of Sweden. The follow-ups that have been made on hybrid aspen stands, have mainly been done on plant material in the South of Sweden. In the North of Sweden, only occasional studies have been made, and the knowledge of Northern hybrid aspen stands is, thus, unsatisfactory.In the South of Norrland, land owners have planted hybrid aspen, but what kind of plants it is, and how well these stands have established, is not ascertained, since data has not been compiled on the subject.The objective of this study is to evaluate practical plantations of hybrid aspen in the South of Norrland regarding height growth, survival and damages. The ambition is to increase the knowledge about practical plantations regarding height growth, survival and damages, and from the conclusions thereof, give recommendations for future establishments of hybrid aspen in the area.For the study, eight hybrid aspen stands in the South of Norrland were localised.

Försämrad korrelation mellan storleken av Kebnekaises sydtoppsglaciär och andra klimatindikatorer

Intergovernmental Panel on Climate Change (IPCC) recognizes glaciers as the best land-indicator of climate change. A variety of studies have concluded, using both modeling and field studies, that above all climate parameters precipitation, particularly winter precipitation, and summer temperature controls the change in glacier mass balance. With global warming almost all glaciers on Earth are losing mass. In this study, the summit-glacier constituting Kebnekaise's south summit (called the Southern-summit henceforth), Sweden's highest point, is studied to see how it is affected by winter precipitation and summer temperature during the period 1968?2013.

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.

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.

Modeller för brösthöjdsålder för tall och gran :

The purpose of this study was to develop two types of prediction models for Scots Pine and Norway Spruce. The first type for calculation of the stump diameter under bark the year the tree reached breast height (Dstubh130). The second type for calculation of the annual difference, e.g. the number of growth years between stump height (0.2 m) and breast height (1.3 meters above ground level). The primary thought with these prediction models is to obtain the breast height age in the trees on basis of the number of annual rings at stump.

Bogbladssår hos suggor : är höjden på tuber spina scapulae en riskfaktor för utveckling av bogbladssår?

Sow shoulder lesions are a common form of decubital ulcers in sows. The wounds are often bilateral and affect both loose housed and restrained sows. In most cases shoulder lesions develop after farrowing and heal after weaning. Sows that once have had decubital ulcera are however more proned to develop new wounds after the next farrowing. The problem is multifactorial and a number of risk factors have been described, including body condition, body size, parity, time spent lying down, flooring, moisture, breed, body temperature and some herd factors. The aim of this study was to investigate whether the height of the tuber spina scapulae is a risk factor for the development of decubital ulcers.

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