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9211 Uppsatser om Soil analysis - Sida 6 av 615

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.

Undersökningsmetodik för klorerade lösningsmedel i marken

Chlorinated solvent are volatile organic substances that can be harmful for humans and for the environment. Examples of common chlorinated solvents are perchloroethene, PCE, and trichloroethene, TCE. Chlorinated solvents appear as contaminants in soils primarily where they have been used as washing fluids in dry-cleaning facilities or as degreasers in metal industries. Chlorinated solvents are DNAPLs (dense non-aqueous phase liquids), which means that they are not easily dissolved in water and that they sink to the bottom of the aquifer. Adsorption to soils is low so chlorinated solvents are mobile in soils.

Fältdiagnostik - ett verktyg för hållbar odling : Resultat och tillämpning av fältdiagnostiska metoder i planeringsstadiet av en ny trädgårdsblåbärsodling

I det här arbetet undersöks fältdiagnostiska metoder och användbarheten av dess resultat i planeringsstadiet av en ny trädgårdsblåbärsodling. Syftet är att fastställa vilken information som kan erhållas från en jordanalys, penetrometerundersökning och en jordmånsbeskrivning samt vilka rekommendationer från dessa undersökningar som vidare kan härledas till planeringen av en ny trädgårdsblåbärsodling. Som exempel och fallstudie används en bit åkermark i Ockelbo där provmätningarna ägde rum.Resultatet visar att fältundersökningar i kombination med en jordanalys gjord på laboratorium är ett bra verktyg för att utreda en jords grundläggande förutsättningar. Jordanalysen visar hur näringsinnehållet ser ut i jorden samt vilka eventuella näringsbrister eller näringsöverskott som finns. Penetrometerundersökningen informerar om eventuella markpackningar, som utgör eventuella hinder för t.ex.

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.

Förekomsten av sura sulfatjordar i Mälardalen : -en pilotstudie utförd åt SGU

Acid sulphate soils is a wide spread problem along the northern coast of Sweden. This is causing great damage through low pH and leaching of metals out into the streams. These soils are estimated to be found in several places in Sweden but also in many other areas in the world. One of these areas in Sweden that are believed to contain these sediments is Mälardalen. The purpose of this study is to evaluate the extension of the acid sulphate soils in this area.

Optimering av reducerad bearbetning : högre skörd till lägre kostnad

Optimization of soil tillage and crop rotation is important in many aspects, but particularly in maximizing profit margins. Since the economic outcome is usually decisive, it can be interesting to study different combinations of soil tillage systems and crop rotations in order to identify the maximum economic outcome. How a crop functions in a particular tillage system determines whether it is profitable to grow that crop. Different tillage systems affect the soil and its processes in different ways. Reduced tillage often works best on weak-structured heavy clays and on silty clays.

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.

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.

Att rekonstruera förhistoriska odlingsförutsättningar : första steget i en metodutveckling.

The aim of this work is to take the first step into a development process, with the intention to find a way of making prehistoric soil fertility a variable in archaeological landscape analysis. A pilot study is performed on the Mälar basin area, where four topographical and geological factors are reclassified and then combined, resulting in a map which expresses a relative indication of agriculture potential. The map is then compared to the distribution of Migration Period graves and gold finds. This, however, does not mean that the technique is tied to a certain prehistoric period. Because the work is intrinsically experimental, the technique as a whole is finally discussed and evaluated, and suggestions of improvements and further studies are made..

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