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681 Uppsatser om Soil moisture gradient - Sida 6 av 46
Geokemin inom osorterade cirklar : Analys av tungmetallers distribution inom jordprofiler tagna från Abiskoområdet, nordvästra Sverige
The Arctic region appears as a pristine remote environment, yet there is increasing evidence that it is greatly impacted by pollution such as lead (Pb) and mercury (Hg). In this environment deposition of Hg has increased threefold since the last industrial revolution. In this study five cryosolic soil profiles within non-sorted circles (NSC) in the Abisko region, northwest of Sweden, has been analyzed to improve our understanding regarding how pollutants are distributed within such type of soil. The soil samples have been analyzed with the use of X-ray fluorescence analysis (XRF), for the measurements of the total concentrations of e.g. lead (Pb) and zirconium (Zr).
Undervegetation : användning av vedartade marktäckare i anläggning
The use of the robust and durable woody ground covers is increasing, not in the least in public places. The group includes low shrubs of different height that effectively build low, tight vegetation that covers the ground. Despite all the good qualities the knowledge about them is quite low and there are ideas about them of being dull.
The woody ground covers manage to struggle against weeds effectively by competing for nourishment and water, but above all, by the canopy of the ground covers that prevent the weeds from getting enough light. In that way the woody groundcovers can effectively compete with the annual weeds.
Sönderdelning av plogtilta med skärknivar :
During the last couple of years it has been more important to reduce the driving on the field to prepair the soil after ploughing. The machine costs are high so it is necessary to be effective. To reach a pleasant soilbed directly after ploughing is sometimes possible on easier soils but heavier clay soils always need more tillages. There is a lot of equipment mounted on the ploughs on the market, for example Furrow Cracker and Furrow presses, which makes a pleasant soilbed on easier soils. The last year Överum and Kverneland have presented knives which are mounted on the wing or moulboard.
Sjunkande pH i Västerbottens humuslager : en kvantitativ analys
Acidification is a central concept in the environmental debate. The effect of acidification of the soil is a matter of a decreasing amount of cations and thereby a decreasing ability to resist a supply of hydrogen ions to the soil. Acidification has gradually increased in the O horizon in Västerbotten over a 30-year period from the 1970th to the 1990th. The aim of this study was from inventories of The Swedish National Forest Soil Survey and The Swedish National Forest Inventory explain and quantify the acidification that has occurred in the O horizon of two regions in the north of Sweden. Data from SMHI, The Swedish Meteorological and Hydrological Institute, has also been used.
3D-visualisering i markprojekteringsprocessen
The thesis has been made for NCC Teknik in Gothenburg. The NCC Corporation is one of the largest leading companies in Scandinavia within the construction industry. NCC is active throughout the whole construction process, where one part is to carry out soil investigations prior the construction of various buildings, for example residential buildings. NCC Technology wants to visualize the samples taken at the construction sites in 3D for clients, authorities and also internally to show in a simple and understandable way how contamination is spread out in the soil.The thesis includes the area of Limhamns läge in Malmö, previously an industrial area. The area has previously included a concrete factory and the contamination from that factory has lingered in the soil.
Autumn water sources for understory vegetation and fungi in a boreal forest : an evaluation using stable isotopes
Understory vegetation and fungi are regarded as important ecological drivers of processes like productivity and nutrient cycling in boreal forests. Whilst those processes are linked to soil water content, relatively little is known about the sources of soil water for these forest
components. During early autumn in boreal forests, temperature falls and large events of rain are frequent which may influence soil water availability. To better understand the autumn plant-soil-fungi water relationships in this ecosystem, I used stable isotopes techniques in this
study to examine the water sources for ericaceous shrubs and fungi in a Scots pine forest following a large, early autumn rain event. I hypothesize that ericaceous shrubs of two functional groups (evergreen vs.
Kväveomsättning i gräsmark med olika artantal och artsammansättningar :
This study was carried out at the Swedish University of Agricultural Sciences, Dept. of
Agricultural Research for Northern Sweden. The aim of the study was to determine how plant species richness and diversity influence the nitrogen pools and nitrogen fluxes in the soil. Plant and soil samples from a biodiversity experiment in grasslands were used. Thirty plots with 12 grassland plant species (legumes, grasses, and non-legume herbs), combined from 1-12 species were investigated.
Soil carbon in small-holder plantain farms, Uganda : a comparison between agroforestry and non-agroforestry
Smallholder farmers in Uganda suffer from declining productivity. With a rapidly increasing population, marginal land is taken into production and the current land
management leads to loss in soil fertility and escalation in soil erosion. There are studies indicating that the use of agroforestry increases soil organic carbon (SOC)
compared to systems without trees. Soils which are high in carbon have many advantages, for example better water holding capacity, which can reduce stress on
crops during drought.
The aim of this study was to determine the effect agroforestry has on SOC concentration in small-holder farming systems in Uganda. The intended system to
study was farms practicing agroforestry methods or not in intercropped plantain (cooking banana) fields.
Rekonstruktion av jordartsförhållanden i Ingarvet, Falun, från geotekniska rapporter
The Falun area has been undergoing mining activity for a very long time and miningslag piled up and was used as foundations for building houses and roads, Ingarvetstarted expanding in the 1970s to an industrial area. The main goal for this report is toreconstruct a soil map of how the landscape was before anthropogenic effects. With thehelp of ArcGIS and geotechnical reports a soil map for parts of Ingarvet, Falun werecreated..
Dimensionering av betongplatta på lös undergrund. En jämförelse mellan tre beräkningsprogram
Today more effective computer programs are in use, regarding design of geotechnicalconstructions. There is a risk that the theoretical background of the computerprograms, its limitations and the signification of the choice of soil parameter isforgotten when the computer programs become more user-friendly.This Master thesis deals with simulation and analysis regarding three computerprograms, FEM-design, with the addition Raft, Plaxis and BE-slab. Comparisons aremade for settlement and maximum moment in a concrete-plate. FEM-design is a threedimensional FEM-program, foremost created for design engineers. Plaxis is a twodimensional FEM-program, intended for geotechnical engineers while BE-Slab is aBoundary elements program in two dimensions that is mainly used by designengineers.
Källor i Lagga, en uppländsk slättbygd : Geografisk och geologisk påverkan påkällvattens egenskaper
For centuries, springs have played a significant role in our society as water supplies, reasons for where to settle down, and in folklore. There are different reasons why and where a spring forms, e.g. in what kind of soil it has its outflow. Geographic and geochemical surroundings have an influence on spring-water quality.For this project some of the springs in the Lagga perish, Knivsta municipality, Sweden, were selected for a closer study. Water samples were collected from springs for analysis.
Skattning av den integrerade hydrauliska konduktivitetens variation kring Tunåsens infiltrationsanläggning : En utredning av påverkan från möjliga osäkerheter i befintlig information
Estimation of the variation in the integrated hydraulic conductivity around the Tunåsen infiltration facility - An investigation of the effects of uncertainties in existing informationAlmost half of Sweden?s drinking water volume is produced from groundwater. The main fraction of this is extracted from eskers, some of which allow for very large extraction rates. Despite this, the groundwater volume is not sufficient in some areas. This has led to an extensive use of artificial recharge.In Uppsala, the total volume added through artificial recharge is divided between four infiltration facilities.
Industriellt byggande – en nulägesrapport
Today more effective computer programs are in use, regarding design of geotechnicalconstructions. There is a risk that the theoretical background of the computerprograms, its limitations and the signification of the choice of soil parameter isforgotten when the computer programs become more user-friendly.This Master thesis deals with simulation and analysis regarding three computerprograms, FEM-design, with the addition Raft, Plaxis and BE-slab. Comparisons aremade for settlement and maximum moment in a concrete-plate. FEM-design is a threedimensional FEM-program, foremost created for design engineers. Plaxis is a twodimensional FEM-program, intended for geotechnical engineers while BE-Slab is aBoundary elements program in two dimensions that is mainly used by designengineers.
Produktivitet vid stubbskörd :
Stump harvest could be found in the late 1970?s and the early 1980?s. And now when the prices on energy are high it has become an interesting topic again. This work has been conducted within Holmen Skog?s stump harvest testing in Norrköping.
Behovstyrd ventilation Ugglumsskolans gymnastikhall
Today more effective computer programs are in use, regarding design of geotechnicalconstructions. There is a risk that the theoretical background of the computerprograms, its limitations and the signification of the choice of soil parameter isforgotten when the computer programs become more user-friendly.This Master thesis deals with simulation and analysis regarding three computerprograms, FEM-design, with the addition Raft, Plaxis and BE-slab. Comparisons aremade for settlement and maximum moment in a concrete-plate. FEM-design is a threedimensional FEM-program, foremost created for design engineers. Plaxis is a twodimensional FEM-program, intended for geotechnical engineers while BE-Slab is aBoundary elements program in two dimensions that is mainly used by designengineers.