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295 Uppsatser om Acid sulphate soils - Sida 6 av 20

Kemisk stabilisering av gruvavfall från Ljusnarsbergsfältet med mesakalk och avloppsslam

Mine waste from Ljusnarsbergsfältet in Kopparberg, Sweden, is considered to constitute a great risk for human health and the surrounding environment. Some of the waste rock consists of sulphide minerals. When sulphide minerals come into contact with dissolved oxygen and precipitation, oxidation may occur resulting in acid mine drainage (AMD) and the release of heavy metals. The purpose of this study has been to characterise the waste material and try to chemically stabilize the waste rock with a mixture of sewage sludge and calcium carbonate. The drawback of using organic matter is the risk that dissolved organic matter can act as a complexing agent for heavy metals and in this way increase their mobility.

Sänkta sjöars inverkan på ytvatten i Västerbottens kustland : Samband mellan sänkningsnivåer och vattenkemi i sjöar på sulfidrika sedimentjordar

Lake lowering in sulphide-rich areas is currently a major environmental impact for surface water. This study focuses on whether there is a relationship between a gradient of lake lowering and surface water impacts in areas of sulphide-rich sediments, in order to better understand their contribution of heavy metals and sulfuric acid. Also, is it a reasonable method to use the reduced lake area in order to quantify the gradient? The survey was conducted by collecting water samples from reference lakes and lowered lakes from south to north in coastal areas within the county of Västerbotten. Water samples were then analyzed for TOC, pH, conductivity, anions, base cations, alkalinity, acidity, sulfate, Al, Cd, Fe, Mn, Cu, Zn and Pb.

Spansk skogssnigel (Arion lusitanicus) i ensilerat vallfoder : betydelse för fodrets näringsinnehåll och hygieniska kvalitet

This work is about silage contaminated with slugs (Arion lusitanicus). The hypothesis was: Do slugs affect the nutritional value and hygiene quality of silage? During the winter season 2007/2008 silages were discarded in big amounts due to the contamination of slugs. Both the Swedish Farmer Association (LRF) and the National Veterinary Institute (SVA) received phone calls from farmers and animal owners about contaminated silage. The Swedish University of Agricultural Sciences (SLU) and SVA decided to initiate this project as a master thesis.

Ämnestransport med grundvatten i hydrogeologiska typmiljöer

Certain types of waste, e.g. bottom ash originating from municipal solid waste incineration (MSWI bottom ash) can be used as road construction materials. A potential problem is the possibility of substances leaching out of the road and spreading in the surrounding groundwater.The aim of this master?s thesis is to conclude whether hydrogeological type settings can be employed to, based on local conditions, provide an estimate of the probable spreading of these substances in the surrounding groundwater, and whether certain types of soils can be identified as being less suitable for the localization of a MSWI bottom ash road. A hydrogeological type setting is defined as a mappable unit with similar hydrogeological properties.

Möjligheter till ökat utnyttjande av fosfor genom grödan med mineralgödselmedel

The objective of this thesis is to explore opportunities to enhance the phosphorus use efficiencyof inorganic fertilizers in crop production, with techniques available today and in thefuture. Phosphorus is a finite resource of declining quality; therefore a phosphorus use efficiencyin crop production of only 15-30 % is unacceptable. The main reason for low efficiencyis the retention by Ca and Mg in calcareous soils and Fe and Al in non-calcareoussoils. Due to the low mobility of phosphorus, plant uptake is mainly dependent on root growthrather than diffusion. Therefore, measurements need to be taken that benefit contact betweenroot and fertilizer, before fertilizer phosphorus becomes unavailable to the plant.

Kemisk stabilisering av gruvavfall från Ljusnarsbergsfältet med mesakalk och avloppsslam : Chemical stabilization of mine waste with sewage sludge and calcium carbonate residues

Chemical stabilization of mine waste from Ljusnarsbergsfältet with sewage sludge and calcium carbonate residuesMine waste from Ljusnarsbergsfältet in Kopparberg, Sweden, is considered to constitute a great risk for human health and the surrounding environment. Some of the waste rock consists of sulphide minerals. When sulphide minerals come into contact with dissolvedoxygen and precipitation, oxidation may occur resulting in acid mine drainage (AMD) and the release of heavy metals. The purpose of this study has been to characterise the waste material and try to chemically stabilize the waste rock with a mixture of sewage sludge and calcium carbonate. The drawback of using organic matter is the risk that dissolved organic matter can act as complexing agents for heavy metals and in this way increase their mobility.

Ammoniakförluster vid flytgödselhantering : myllning och surgörning som metoder för att minska avgång vid spridning

The ammonia emissions are an environmental issue since they contribute to eutrophication. By far the largest source of ammonia emissions is manure from agriculture and should therefore be reduced. Loss of ammonia is not only negative for the environment but also to the farmer who loses nitrogen that could have been used by the crop. The focus of this study has been emissions from spreading slurry where the loss can vary widely depending on slurry-, soil-, and weather conditions. There are mainly two different ways to reduce the emissions. One is to inject or mix the slurry into the ground to avoid air contact. The other way is to use acid to reduce the pH in the slurry to a level between 5 and 6 where the equilibrium is so strongly pushed to NH4+ that hardly any NH3 can be lost.

Effekten av tillskott av CLA på kroppsvikt och andel kroppsfett hos överviktiga och feta

Sahlgrenska Academyat University of GothenburgDepartment Of Internal Medicine And Clinical NutritionAbstractTitle: The effect of CLA on body weight and body fat amongst overweight and obese.Author: Sierra De Goldsmith and Amanda EgebergSupervisor: Frode SlindeExaminer: Anna WinkvistProgram: Dietician study program 180/240 ECTSType of paper: Examination paper, 15 hpDate: April 12, 2012Background: Overweight and obesity represents a global problem as it is accompanied by an accumulation of body fat which increases the risk of developing diseases such as diabetes type 2, insulin resistance, cardio vascular diseases and certain types of cancer. Moreover, the prevalence is increasing worldwide. Many consider it difficult to reach a normal weight using only methods such as changing dietary- and exercise habits, this creating a market for products that facilitate weight loss and loss of body fat. The supplement of conjugated linoleic acid (CLA) is such a product. In animal studies, CLA has demonstrated a reduction in both body fat and weight.

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.

Tillförsel av använda fosforfilter påverkar inte tillväxten eller fosforupptaget hos korn

The eutrophication of inshore seas, lakes and watercourses is mainly due to leaching of nitrogen and phosphorus (P) from agriculture. Many efforts are made to reduce the lea-kage of phosphorus in Sweden and the Baltic Sea countries. Phosphorus is also a finite resource and the mining of good quality raw material gets more and more difficult. Se-dimentation dams in combination with filters is one relatively new method to separate P from run-off and drainage water from agricultural land. This study was a part of an IVL Swedish Environmental Research Institute?s project which tests the capacity and func-tion for separation of phosphorus in four phosphorus filters.

Plant defensive mechanisms against insect pests

This study has focused on testing the following two hypotheses:? Pest resistant plants have higher levels and/or several different kinds of secondary metabolites. ? Induced defensive systems in resistant plants are activated more rapidly than those of susceptible plants. As a background for the test of the hypotheses a short literature study was performed concerning plant defensive mechanisms in Arabidopsis thaliana.

Fett - rekommendationer, kostvanor och konsumtion mellan 1935 och 2009

This literature research is meant to answer the following questions: ? What was the Swedes consumption of fat from 1935 to 2009? ? How has the fat consumption corresponded to the current recommendations? ? What is LCHF and which are the main advantages and disadvantages? Fat supplies us with energy, isolates and protect organs from bumps and punches. Fat is insoluble in water but soluble in organic solvents. The properties of a fat depend on its structure. The most common fat in human food is triacylglycerides.

Stubblyftningens initiala effekt på emissioner av växthusgaser från en granmark i Småland :

In order to reduce greenhouse gas emissions from human activities fossil fuels will have to be replaced with renewable energy alternatives, such as bioenergy. Sweden has a great potential to produce bioenergy derived from forest products and there is currently a great interest within Sweden in using stumps for bioenergy production. However, the environmental consequences of the method need to be investigated before stump removal can be performed on a large scale. Swedish forest soils contain large carbon pools and a different land use may change conditions so that soils that presently act as sinks of carbon could potentially turn into sources of carbon release instead. This study investigates the initial effects of stump harvesting on the emissions of three greenhouse gases, carbon dioxide, methane and nitrous oxide. The emissions were measured from the soil surface in a Norway spruce forest located in the southern part of Sweden.

Dairy fat biomarkers and cardiometabolic health

Commonly held dietary guidelines discourage full-fat dairy consumption due its to high levels of saturated fatty acids, which are believed to aversely influence cardiovascular disease risk. Cardiovascular diseases cause more than one third of deaths in the developed world. With dairy often providing a large part of energy and nutrients in Western diets, research into its effects on human health is warranted. Several recent studies have suggested a protective role of dairy in the development of cardiometabolic disease. However, many of these have used imprecise methods of dietary assessment, based on questionnaires or interviews. Biomarkers are emerging as a means of evaluating diet in a more objective way. Currently used dairy fat biomarkers are minor fatty acid constituents of dairy that preferably are unique to dairy and not influenced by endogenous metabolism.

Hur kan blöt vetedrank lagras, hanteras och utfodras till mjölkkor? :

Distillers? grain is a by-product of ethanol production. Corn, wheat and barley are the grains that are generally used in the distillery process. Distillers? grain is rich in protein and phosphorus.

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