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2050 Uppsatser om Soil types - Sida 6 av 137

Bärförmågetillväxt i pålad friktionsjord

Piled friction soil show a set-up which is increasing with the time after installation. The cost could be reduced if the set-up had been taken into account when designing but in Sweden it is very unusual to do that. Previous studies showed that set-up can vary between 25 % and 75 % during the first 90 days after pile installation. This showed that the effect of the phenomenon is difficult to predict. A study involving five projects have been carried out by specifying certain parameters like pile type, method for pile installation and test method for measure the bearing capacity in friction soils located in Sweden.

Djup icke vändande bearbetning i sockerbetsodling :

A field experiment was carried out in 2006 to investigate the effects of deep rotary cultivation on sugarbeet growth. The background to the experiment was a 2005 study showing potentially higher yield, higher cleanness and higher sugar content when primary tillage was carried out to 35 cm depth with a rotary cultivator. On four field sites in Skåne (L:a Isie, Ädelholm, Stävie and Vragerup), five different treatments were compared: mouldboard ploughing in the autumn to 20 cm; mouldboard ploughing in the autumn to 20 cm + rotary cultivation in the spring to 35 cm; rotary cultivation in the autumn to 35 cm; rotary cultivation in the spring to 35 cm; and mouldboard ploughing in the spring to 20 cm. The rotary cultivator used in the treatments is manufactured by a Dutch company, Imants. The implement cultivates the soil with spade tines fitted on arms that are mounted on a horizontal rotating PTO-driven axle. Beet plants were inspected and yield determined in the experiment, and three soil parameters were examined: penetration resistance, water infiltration and infiltration of blue dye. Root shape was also examined. The site at Stävie was not harvested due to poor beet establishment. At the other sites, the highest yield was found when the soil was rotary-cultivated in the autumn.

Bättre åtkomst till avverkningstrakter med anpassat marktryck från avverkningsmaskinerna

The global climate-change means increasing mean-temperature and higher precipitation in Sweden, which leads to shorter periods of frozen ground in the forest. At the same time the harvesting machines are getting bigger and more powerful. The forest industry aim at an even wood flow, and the ground damage has to be as low as possible. The two biggest causes for ground-damage is the bearing capacity of the forest ground and the ground-pressure of the harvesting machines. The aim of this study was to find out some rules for the machine choice considering ground pressure, when harvesting on ground with low bearing capacity.A field study, using a Valmet 890.3 forwarder, was carried out where different ground pressures and their effect on the ground were tested on two different types of ground.Additionally, an inventory of damaged harvesting grounds was made.

Hackerör på Sydsvenska höglandet : vad skiljer röjningsröseområden från celtic fields, stensträngsområden och bandparcellområden?

From the pre-Roman and Roman Iron Age, a number of different fossil agrarian landscapes can be found in southern Sweden - clearance cairn areas, celtic fields, stone-wall complexes and geometrically laid-out strip fields. With two different comparative analyses, this paper tries to explain some of the differences between clearance cairn systems and the other fossil field systemsThe shape of the early Iron Age agrarian landscape varies between different provinces of southern Sweden. At Gotland, celtic field systems were laid-out before 500 BC. In Småland at the same time, areas with clearance cairns were created. How can the difference be explained? The different physical appearance of clearance cairn areas and celtic fields can be explained by the different ways to handle the ard in till and in sandy soil.

The legacy of the mill : a metal polluted forest soil in Gusum

Soils in a metal contaminated site on Stångberget in Gusum in southeastSweden were investigated and compared to relatively unaffected soils a fewkilometres away. Pollution came from historical release of untreated flue gasesfrom a brass mill. The objective was to find information on how high the metalconcentrations are, if metals from the polluted soil affect the surroundings andif the metal contamination affects the microbial community. The soil wasinvestigated using several different methods, such as field XRF measurements,chemical analysis of metal, carbon and nitrogen content, pH, acid neutralizingcapacity, texture, soil depth, field leach tests, sequential extraction and microbialfunctional profiles. The study showed that copper and zinc concentrationswere above Swedish Environmental Protection Agency guidelines for lesssensitive land use on the entire investigated area.

Däck-mark Interaktion hos skogsmaskiner

The most predominant method for forest harvesting in Sweden is the cut-to-length method based on two-machines, a harvester that fells trees and cut them in a predefined length, and a forwarder which transports logs to a landing area for further transport to a processing facility. New machine solutions have to be much gentler to the ground than today?s machines. To be able to develop a forestry machine that preserves the terrain requires a proper understanding of the interaction between tire and soil.The goal of the project is to contribute to the existing knowledge of forest machine tire-soil interaction and to develop a tire-soil model that enables dynamic simulations of forest machines operating in rough terrain. The modeling has especially been focused on the interaction between tires and soft ground.A comparison of theoretical data of different WES-based terrain interaction models and a comparison test data from a full scale field test is presented.

Kalkningens påverkan på fosforlöslighet : skakförsök baserade på två svenska långliggande kalk- och fosforgödslingsförsök

Eutrophication is an environmental problem that affects more than ten percent of Swedish lakes. Excess nutrients increase the growth of algae, and cause major problems in the ecosystem through oxygen-free bottoms, fish kills, and at worst dead bottoms. Agriculture accounts for 44% of human emissions of phosphorus to lakes and rivers. Leaching occurs of particle bound phosphorus and of dissolved phosphate. The amount of phosphate in the soil solution that may be leached is partly due to the prevailing pH in the soil solution. The purpose of this study was to investigate how the relationship between phosphate solubility and pH was affected by liming.

Koldioxidavgång vid ekologisk odling på organogen jord

The background of this work is the media discussion about the effect of cultivation on peatsoils on greenhouse gas emissions. It has been argued that row sown and intensivelycultivated crops such as carrots are more likely to emit carbon dioxide than for example grassleys. The association KRAV (an association promoting organic farming) shall, from this yearadapt their environmental policy to be more climate smart and have asked the question if thecultivation of some crops is more climate smart than others? Carbon dioxide emissions fromsoil are due to degradation of organic material and the rate is controlled by microbial activity.The microbial activity is determined by a variety of factors such as temperature, soil organicmatter quality and water content. I have measured the carbon dioxide emission from fourdifferent crops at two different farms.

Biochar as soil amendment in flow-through planters - for increased treatment of zinc roof runoff

In times of increased flooding, enhanced by climate change, polluted stormwater poses an increased threat to the environment through contaminated water entering waterways. Bioretention utilizes natural processes in soil and vegetation to treat pollutants and combat this threat. Biochar produced through pyrolysis, has a high cation exchange capacity (CEC) and could therefore increase treatment in bioretention systems. This research applies a literature review, interview, and a model to explore the benefits and disadvantages of biochar in order to specify a soil-mix through an understanding of the production process and preferred application rate. High purification through CEC, increased water holding capacity, and carbon sequestration being the benefits discussed.

Aggregatstabilitet, jordbearbetning och fosforförluster i ett typområde på jordbruksmark :

Large amounts of phosphorus (P) are lost from the arable land due to water erosion. Both phosphorus attached to particles and dissolved phosphorus (mainly phosphate) are transported away with drainage-water and surface runoff. Good soil structure is important in minimizing these losses. In this study, soils from 50 fields were analysed with respect to aggregate stability as measured by dispersion of clay together with the content of total phosphorus (TotP), particulate phosphorus (PP) and phosphate phosphorus (PO4P) in the water phase. All soils were clay soils with clay content varying between 21 and 54%.

VäxtVäktare

Most people have been forced to throw away a pot-plant after its death. There are many reasons to the death of a plant, but mainly it?s because its owner forgets it, and therefore fails to water it. The purpose of this project is therefore to develop a product which can prevent this from happening, while the product has to have a low manufacturing cost to be able to compete whit other, similar, products on the market. During the project, a benchmarking has been done to give a clear picture of what the product has to compete with. The directives there are for CE-marking, and which of these who concerns the product has also been looked up.

Vallbrott med hjälp av grisar :

To investigate the possibilities for effective soil tillage, that could imply lower costs, lower negative environmental impact and in addition a meaningful occupation for foraging pigs, a field experiment was carried out in Gränna, Småland, during growing season 2006. The experiment contained two treatments that were repeated three times and were carried out on a couch grass-infected fallow on a light soil close to Sweden?s second largest lake, Vättern. Ploughing was one treatment and pig rooting followed by ploughing, was the other. The experiment was conducted according to the guidelines of organic growing and seedbed preparation was done the same way in the two treatments. The pigs, three groups of five half-year old Linderödssvin (an old Swedish breed), was encouraged to perform an even tillage by strip-grazing, i.e.

Migration och vegetationsupptag av radiocesium i åkermark - en långtidsserie av mätdata samt en långsiktig simuleringsmodell :

Abstract The accident in 1986 at the nuclear power station in Chernobyl, Ukraine, dispersed radioactive cesium over large areas of Europe. The half life of 137Cs is 30 years and this radionuclide also behaves like potassium, which means that it can easily be taken up by the vegetation or be adsorbed in to the structure of clays, principally illitic clays. When radiocesium decays ionizing radiation is emitted, which is harmful to humans that are exposed, either directly or indirectly through food intake. It is there-fore important to know what happens to the cesium that is dispersed into the environ-ment. In this project a simulation model was constructed to simulate the adsorption and transport of radiocesium in the soil and plant uptake.

Avgränsning av tillrinningsområden till grundvattenmagasin : vilken information ger berggrundens överyta?

Delineation of recharge areas for aquifers is performed in the groundwater mapping process at the Swedish geological survey, SGU. This work is time consuming and performed manually. It is therefore desirable to develop a more general and repeatable method for defining recharge areas for aquifers.The purpose of this study was to investigate two other possible methods to delineate recharge areas for aquifers. The first method was to examine the possibility of using the topography of the bedrock to define the recharge areas for aquifers. To enable this, a method for generating the topography of the bedrock was developed.

JB-TOTALSONDERING : Jämförande sonderingar och utvärdering av egenskaper i isälvsavlagringar kring Igelstaviken

The main purpose of this thesis has been to find a way to evaluate the soil parameters for the Total sounding method (TS), such as the inner friction angles and settlement modules. This study only includes an analysis of soil profiles from the Stockholm region. The chosen location for the study is a proposed residential area east of Igelstaviken in Södertälje. Presently, the subject plot is located in a residential area and is also adjacent to a school area.Total sounding is originally a Norwegian soil testing method. The differences between the sounding methods (weight-, ram-, CPT-sounding) are for instance how the sound is driven into the ground and what kind of parameters that are registered.

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