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763 Uppsatser om Soil carbon - Sida 21 av 51

Modellering av reflektans från ett sockerbetsbestånd med hjälp av en strålningsmodell

The Multispectral Canopy Reflectance Model (MCRM) by Kuusk (1995) has beenused to simulate the reflectance of a sugarbeet canopy. The simulated reflectancevalues show high absorptance in the VIS area, compared to field measurements, andhigh reflectance values in the NIR area. The errors may be due to overestimation ofclorophyll content in the sugarbeet leaves and scattered light during fieldmeasurements. The estimation of the clorophyll content where carried out using thePROSPECT-model by Jacquemoud & Baret (1990).During the vegetation period, the state of the canopy moves towards a closed canopy,with sparse vegetation in spring. The MCRM-model was used to perform a ?spring?simulation, which was compared to the original simulation.

Elasticitetsmodulen i en kalkstabiliserad vägterrass : en fältstudie

Stabilization of subgrade is an internationally common technique to improve the characteristics of a soft soil. Improving the stiffness and bearing capacity of the subgrade enables the pavement to be designed with reduced depths of subbase and basecourse aggregates. This makes the stabilization technique both economically and environmentally interesting. Both natural and stabilized soils have high inherent property variability that should be considered when the characteristic value is derived. By analyzing the spatial variability in stabilized and natural subgrades it is possible get the parameters needed for reliability?based modeling of soil properties.

En jämförelse av RDF och avfall som förbränningsbränsle

In the EU the amount of waste increased by 14 percent during the years 2000 to 2010. EU?s target to reduce waste generation runs parallel with the aim of increasing the efficiency and profitability aligned with energy recovery. In Sweden the energy recovery through incineration is increasing steadily, and 46 percent of the municipal solid waste (MSW) is treated by combustion. This report aims to examine the profitability of processing MSW into Refuse Derived Fuel (RDF) from an economic-, energy- and environmental perspective.

Energianvändning för markkonstruktioner förlagda med ytvärme : En teknisk och ekonomisk utredning av fördelarna med att isolera under värmerören

The need for snow-free surfaces at squares, bus stops, platforms, car parks and sports facilities increases and at the same time energy price rise and the environment is becoming a hotter issue. The construction of the ground heating systems often lack thermal insulation under the heating pipes, which means that the heat from the pipes not only warm up the soil surface but also heats the surrounding soil. The insulation also has more features, by insulating the risk of frost damage is minimized. The goal of this report is to demonstrate the large heat loss and energy costs in the absence of insulation under the heating system.The report begins with a scientific way to study and treating the soil heating system uses, and the theory involved. Furthermore it also deals with different routing principles of heat pipes depending on the facility.All calculations are made with so called finite element method (FEM), in COMSOL Multiphysics 3,5a, where models are created with different conditions.

Miljöanpassad offentlig upphandling: effektivt styrmedel mot koldioxidutsläpp? : En studie av kostnadseffektivitet, transaktionskostnader och teknisk utveckling

Green public procurement (GPP) can be used as an instrument to reduce carbon dioxide emissions, and consideration of environmental aspects within public procurement is becoming more common in Sweden and internationally. Two product groups that have been pointed out as especially important are transports and electricity, where the opportunities for public purchasers to reduce emissions are relatively large. This paper studies GPP which aims at reducing emissions, primarily of carbon dioxide, through environmental requirements within these two product groups. A theoretical analysis of cost-effectiveness, transaction costs and effects on technological development is performed, followed by a closer study of how these aspects appear in practice within GPP. The results indicate that a cost-effective allocation of reductions between the two product groups is most likely to be attained if the main part of emission reduction is achieved through environmental requirements on electricity. The cost for emission reduction within transports is relatively high, especially for heavy transports. For transportation services, more generally focused requirements on emission reductions could probably give greater environmental gains, but the existence of transaction costs steer the environmental requirements towards more technology specific types.

GIS och statistik vid dräneringsområdesvis kväveläckagebeskrivning i Halland

The last decades have shown increased nitrogen leeching from soil to water recipients. This is inSweden mainly due to over-manuring of agriculture land, effectivization of drainage systems and thedeclining extent of wetlands. The accumulated amount of nitrogen in water doesn?t only make itunsuitable for use by humans and cattle, but also decreases the biological diversity as well as negativelyaffect tourism and fish industry. In the most severe cases shallow maritime grounds can be completelydepleted of oxygen due to decomposition of the increased amount algae and plankton growth.This study have the aim to describe and quantify the nitrogen leeching from the Genevad drainagebasin, located in southern Halland, Sweden.

Smart seed : fördröjd groning hos raps : försök med frö-coating samt litteraturgenomgång om frögroning, coating och praktisk tillämpning i reläodling

Oilseed rape constitutes a good break crop within a cereal dominated cropping system. The normal sowing time for winter rape in Sweden is August. It's a time in the cropping year characterized by a heavy work load, such as harvest and soil management. In addition, it is often a period with large precipitation. Thus, it is sometimes problematic for the farmer to do the sowing of winter rape at the optimal time.

Vindfällning i naturliga och skapade bryn och kanter :

The aim of this work was to study if the edge of the forest is more resistant to heavy winds than the trees located further in from the edge, and how this edge effect changes between different types of tree species and site types. The data was collected from an electric power line going from the north to the south of Sweden. The mean value of the clearcutted area around the power line was 120 meters. The main direction of the storm in January 2005 was west-southwest and thus the power line was a perfect place for gathering a large data set. The main parameter studied was the damage frequency at the edge of the forest compared to the trees located further in from the edge (up to 100 m from the power line). Tree species mixture, soil moisture class, soil type, topography, stand height, stand height of the stand on the other side of the power line and wind exposition was estimated. The results showed a distinct edge effect. The edge of the forest had clearly lower damage frequency for all tree species. A marked difference was observed between tree species and damage frequency.

Varnhems tidiga kyrka och kyrkogård : Isotopanalys av skelettmaterialet i området

This paper deals with stable isotope analysis on the children of the early Christian cemetery in Varnhem, Västergötland. Human bone and tooth material from the cemetery has been analysed for stable carbon, nitrogen and sulphur isotopes. The analysis showed that the diet had been homogeneous and that the children had been breastfed, with a possible exception of the child from grave 100..

Trädgårdar på tak- och gårdsbjälklag :

The purpose of this thesis is to collect knowledge of techniques and materials for planning roofgardens. Gardens built on top of buildings is not a new phenomenon, already in the beginning of the century architects were experimenting with roofgardens. During the Modern Era roofgardens appeared as a part of the design and worked well together with flat roofs and the ideas of light, air and greenery. Today the most common kind of roofgarden is on a ground-level joist that hides parking or other underground functions. The most important difference between planning a roofgarden and a garden on the ground is the limitation of the load of the roofgarden. Plants, paving-material and equipment must be chosen with this in mind. A light and thin layer of soil demands plants with small needs for water and nutrition.

Giraffens blodtrycksreglering

Through previous studies during my education, I have experienced that chemical deicing road salt is a known problem, mainly in southern Sweden. Road salt causes damage to the environment and also damage to vehicles and structures such as bridges, etc. Road salt causes vehicles and steel constructions to rust, leading to increased costs for repairs of damage to structures. Road salt also causes damage to the plants and the economy to suffer, when plant material and soil needs to be replaced. In order to get closer to a solution, I put up three questions.

LIP : en effektivitetsstudie

Lokala investeringsprogram was a subsidy program which supported environmental reforms during the years 1998 to 2002. The subsidies were given to Swedish municipalities. Most of the evaluations of the subsidised projects have now been completed and included in a database. The purpose with this thesis is to analyse whether the instrument has been effective with respect to carbon dioxide reductions and costs. These calculations have focused on subsidy and cost efficiency. The analysis has been compared with a previous report called "LIP ur ett samhällsekonomiskt perspektiv". The result shows that the reduction cost for one kg CO2 has been almost one SEK, which is twice as high as the cost reported in a previous report, half a SEK.

Pilotstudie för att utvärdera effekten av L-Mesitran : honungsbaserad sårsalva : vid behandling av yt-pyodermi hos hund.

Green manuring is a way of creating an organic fertilizer by growing a crop that is mowed down. Besides the fertilizing effect this method has been shown to have a positive influ-ence on soil organic matter as well as weed flora, and green manure is an important me-thod of weed control in organic farming in parts of Sweden. However, the release of nu-trients from the green manure varies and can therefore be difficult to control. Risks for losses of nutrients are also present. Although the area of organic farmland is increasing in Sweden, the use of green manure is decreasing.This report contains a literature study which compiles research on the functions of green manure in a cropping system and also how the crop can be used if harvested, for example to produce biogas.

Plantering av gran (Picea abies) på kalhyggen och självföryngring under högskärmar av björk (Betula pendula och Betula pubescens) : föryngringsresultat 7-10 år efter avverkning

The aims of the silvicultural method natural regeneration of spruce (Picea abies L. Karst) in birch (Betula pendula and pubescens) shelterwoods are to establish a new stand of tree seedl-ings and to protect those from high groundwater levels, frost damages and grass competition during its first life years. The aim of this work has been to (i) describe how shelterwood and stand characteristics influ-ence the results from using natural regeneration of spruce protected by a shelterwood of birch, and to (ii) compare those regeneration results with planting of spruce after soil scarification in clear-cut areas. Totally 17 harvesting sites have been inventoried and 15 of those included natural regenera-tion in birch shelterwoods, and two were subjects to soil scarification and planting of spruce. The sites represented 7-10 year old final cuts and are located in the coastal (eastern) region of the province of Norrbotten in Sweden. In all areas shelterwood and stand characteristics, as well as the number of main crop seedlings and the height of the highest main crop spruce seedling, were estimated and registered in all areas.

Hantering och mellanlagring av jordmassor

This report deals with handling and interim storage of soils which are planned tobe reused in construction works. The types of soils that are dealt with are gravel, topsoil and sand. The thesis work has been carried out in collaboration with Skanska Sverige Väg och Anläggning Sydost. The main goal is to find an area for using to store soil in between projects.Studies of laws and regulations regarding exploitation and storage of soil has led to a theoretical background upon which the report is based. Background informationhas also been gathered in meetings with the employees at Tekniska Kontoret and Länsstyrelsen in Jönköping.On the basis of literature studies results, a general template has been developed for which desirable properties a possible location should meet.The model was applied to find a number of possible options in the vicinity of Jönköping.

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