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987 Uppsatser om Soil concrete - Sida 14 av 66
Hur stor areal äldre skog lämplig för trakthyggesbruk finns det på Gotland 2013?
The degree project at hand investigates how large areas of older forest (80 plus years) suitable for clear cutting there is on the Swedish island of Gotland. Large areas of older forest on Gotland are situated on land with shallow soil depths which are economically uninteresting and often unsuitable for clear cutting forestry. Other forests hold big nature conservation values and should not, or cannot, be used for forestry purposes.
The survey is made as a GIS analysis based on the old but carefully made ?Brief forest inventory? (ÖSI) made in the 1980s and early 1990s. A sample from the inventory is combined with studies of orthophotos, satellite photos and other GIS layers that display estimated soil depth and nature conservation values.
Partly contrary to common belief, the survey shows that there are still large areas of older forest suitable for clear cutting forestry on the island.
Komfortsanalys med hänsyn till vibrationer orsakade av människoaktiviteter. : Ett modernt dimensioneringsproblem för huskonstruktörer
Comfort analyses regarding human induced vibrationsIt is not too common among civil engineers in Sweden to perform comfort analyses considering the vibrations caused by human activities. In addition, the Swedish standards lack requirements to be used for comfort analyses in design of floor-systems. The demand for large spans in combination with slender slabs, is today a reason to investigate the floor-system constructions, in order to prevent disturbing vibrations and oscillations.The purpose of this thesis is to create a guide for how a comfort analysis, considering vibrations, should be implemented. Göran Svedenbjörk who is an expert in structural dynamics has been interviewed where he presents his latest project Värtaterminalen and answers some questions about vibrations due to human activities.Floor-systems, consisting of concrete slabs supported by steel or concrete beams, have been investigated with simulations in the finite element program Abaqus. In the simulations, the influence of various factors on the natural frequency of floor-systems and the acceleration level caused by dynamic loads, is studied.
Människan i urskogen : vegetationshistoria i Hamra nationalpark under 2500 år
Pollen analysis of a peat core was used to reconstruct the last 2500 years of vegetation history, with focus on the impact of anthropogenic disturbance, in Hamra National Park, central Sweden. In addition, analysis of pollen in soil samples was performed in an attempt to locate ancient cultivation plots in the National Park.
The analysis of the peat core shows a development of the vegetation that can be divided into four stages of different degrees of human impact: A - virgin forest (c. 500 B.C.-A.D. 1300), B - grazed forest (c. A.D.
Kompostering av köksavfall och användning av kompost i köksträdgård i Chazuta, Peru : jordförbättring och/eller lösning på ett avfallsproblem?
All over the world the waste from human society is causing problems. In developing countries, large cities are polluted through huge amounts of wastes and people are forced to live very close to open deposits. Lima, capital of Peru, is no exception. The countryside in Peru has also a great challenge to face concerning the waste issue. Children and adults suffer from infectious diseases and contamination of the nature occurs as well.
One solution to handle organic waste is to compost, which means a controlled decomposition
of organic waste under aerobic conditions at certain temperatures.
Markskador vid GROT-uttag : en enkätstudie hos skogstjänstemän
Forestry is increasing on an industrial scale where collection of logging residues takes a greater part. This has resulted in more machinery and heavy machinery driving in the clear felled area, this increases the risk of soil damage that will occur in the form of soil compacting and rutting in the clearings. This affecting on the nature in a negative way and especially in rivers and lakes that are affected by siltation and acidification leading to increased levels of heavy metals and methyl mercury. The purpose of this study was to investigate why there is damage to the ground when working with the slash in forest management from the forest officer point of view. A self-designed questionnaire was used and 45 questionnaires were sent out to various companies all over Sweden.
Effect of liming and free Ca2+ on Cd uptake of carrots, Daucus carota
The level of cadmium (Cd) in Swedish arable land has increased during the last century and the average concentration of Cd in the plough layer is today 0.23 mg/kg. The increase is mainly due to anthropogenic activities such as phosphorus fertilizing, liming, import of feed, and atmospheric deposition from industrial emissions. Cadmium in the soil will be taken up by crops and is thereby transferred to humans via food. Carrot is one of the crops of concern, both because it may contain quite high Cd concentrations and due to the large consumption in Sweden. In the body, Cd is stored mainly in the liver and the kidneys and may cause several diseases already at low concentrations.
Hur påverkar byggnadsmaterial av stål en induktiv hörslingas fältstyrka samt frekvensgång?
This research analyzed differences in measurements of magnetic field strength and frequency response in five audio induction loops installed in rooms of wooden construction materials and five audio inductive loops installed in rooms of steel reinforced concrete constructions. The inductive loops were installed at floor level and the measurements were made at the listening height of 1.2m. Measurements of background noise, field strength and frequency response were made at fifteen different measurement points across the room. The research measurements showed that there are differences in field strength and frequency response between these two conditions, whether the audio induction loop is installed in a wooden construction or the audio induction loop is installed in a reinforced concrete construction. The results had a significance level of p=0,05..
Miljögifters exponering, ackumulering och effekter på immunsystemet hos husdjur :
The purpose of this literature review was to describe the paths of exposure and accumulation of organic pollutants into the tissues of farm animals. Organic pollutants can be spread in the environment by air and rainwater. Farm animals can be exposed to these pollutants for example by eating soil or contaminated plants. Many of the pollutants can then accumulate in the fat tissues of the body because of their lipophilic character. Brominated flame retardants and perfluorolated compounds are both pollutants of current interest.
Uttorkning av lera : Orsaker och följder
When building a house or similar the stress on the ground increases and deformations can arise. The deformations create a foundation that the building is not constructed for and damages on the building arise. The increased stress on the ground can be derived back to the building, but it is possible that the increased stress may well derive from different sources such as other buildings or trees. The building is an older property, built in the late 19th century alternatively early 20th century, and is today used for rental housing and has suffered severe damages due to subsidence. The goal of the thesis is to find possible causes for these subsidences. The thesis was executed as a combination between literature- and casestudie. After careful studies it has been found that a probable cause for these subsidences is trees. Through field- and lab studies it has been found that the trees has effected the ground through there accumulation of water.
The secret life of Bacillus anthracis
Bacillus anthracis is the causative agent of anthrax, a serious and globally distributed zoonosis affecting a wide range of wild and domestic animals, invariably also humans.
However, although known to humans since biblical times, much remains to be elucidated concerning the ecology and transmission of this bacterium. Of particular interest is the Bacillus anthracis spore, the uptake of which is the predominant way to contract anthrax and which is legendary for its resilience in the environment and thus crucial for persistence and spread of the disease. Hence, the aim of this study is to review the natural transmission of
Bacillus anthracis and investigate potential means by which soil persisting Bacillus anthracis spores reach concentrations sufficient to infect susceptible hosts. When reviewing the literature, three different theories can be distinguished. Firstly, ?the incubator area? hypothesis suggests that favourable soil factors, possibly in association with amoebas, may constitute an environment supporting repeated spore-bacterium-spore cycling, thus increasing the local amount of spores.
Platsanalys, grunden för en gestaltningsprocess
Uppsats för avläggande av högskoleexamen i Kulturvård, Trädgårdens hantverk och design 7,5 hp, 2014.
Kartläggning av föroreningars förekomst och spridning i Gräsötippen enligt MIFO
It is estimated that 22 000 contaminated areas exist in Sweden today. In order to classify the risk of contaminant migration from these areas and to prioritize which of these contaminated areas should first be treated, the Swedish Environmental Protection Agency (EPA) has designed a method, for the investigation of contaminated areas (MIFO). One of these contaminated areas is the landfill Gräsötippen outside Köping. The landfill has been used by both Yara AB and the Köping municipality between the years 1945 and 1975, and both industrial and household waste have been deposited there. The aim of this report is to survey which contaminants that can be found in the soil and water in the landfill Gräsötippen and to evaluate the migration of these contaminants.
Genus i musikämnet : En analys av tidskrifter riktade till musiklärare
The school inspectorate surveys illustrates problems and difficulties for teachers to suit individualized instruction. Therefore, the purpose of the study to investigate whether and in what ways some pedagogues experiences and practice offers the individualized instruction that the governing documents require. The study is based on a qualitative method in the form of semi-structured interviews and observations with four experienced pedagogues. I have been using Piaget's theory of the concrete material's importance for learning and also Vygotsky's theory of the proximal development zone. The results showed that pedagogues understand the importance of individualized instruction.
Klimatförändringars påverkan på kulturmiljöer i Uppsala stad ur ett geovetenskapligt perspektiv
Cultural heritages are environments created by humans that are considered to have a conservation value for the posterity. They can be seen as one of society's non renewable resources. It is important to have knowledge of how cultural heritages are affected by future climate changes.The water flow in Uppsala is estimated to increase during winter and decrease during spring and summer. Precipitation will gradually increase as well as the intense short period precipitation. The average temperature is estimated to increase as well.
Anva?ndning av markfuktighetskartor fo?r sta?ndortsanpassad plantering
Digital depth-to-water maps can be produced from a digital elevation model (DEM). Then GIS- based algorithms are used to calculate water flows and the depth-to-water index classes dry, fresh, moist and wet. The purpose of this study was to investigate the possibility to use depth- to-water maps for site adapted planting.The results showed that use of depth-to-water maps for site adapted planting, roughly halved the proportion of improperly planted surfaces from an average of 9 % to 4 %. The variation in the values of proper surface decreased and the result became more even.. In addition, more pine than spruce was incorrectly planted.