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295 Uppsatser om Acid sulphate soils - Sida 15 av 20

Kaliumgödsling på torvmark - effekt på tillväxten hos planterade granar (Picea abies)

Peat  lands  are  a  great  potential  resource  for  increased  forest  growth  in  Sweden, there  are  approximately  6.5  million  hectares  of  peat  lands,  whereof  around  70% produce less wood than one m3sk/ha and year and are therefore classed as forest waste  land.  There  are  over  200  000  hectares  of  peat  land  that  is  already  drained and  wooded,  and  that may  be  suitable  for  fertilization.  Forest  production  on  peat soils  usually  requires  drainage  and  fertilization.  Dewatering  requires  ditching  the area, so that the roots can have access to oxygen. Nitrogen is often abundant in the peat but other nutrients; especially potassium is in short supply. The  purpose  of  this  work  was  to examine  the effects  of  potassium  fertilization  on the  growth  of  spruces  that  were  planted  on  drained  peat  land  and  how  different amount of fertilizers affects the growth. Potassium deficiency is strongly growth inhibiting, since potassium is important for substance  transport  in  the  tree.  Potassium  is  also  important  for  the  carbohydrate formation, and because increasing the sugar content of the cells constitutes a lower freezing temperature does potassium availability in the soil play a major role in the winter  resistance  of  many  species.  Potassium  is  not  found  in  any  organic compounds in the tree, but is present in cell and tissue fluids. A fertilization trial was started in 1978 in Siljansfors Experimental Forest. The plots in the experiment were fertilized with different amounts of potassium and one plot was  left  without  fertilization.  All  plots  that  were  fertilized  with  potassium  grew considerably better than the unfertilized plot. The difference in production between the unfertilized plot and the plot that received the most potassium was 7.2 m3sk/ha and year. The unfertilized plot can still be classified as waste land. The theoretical production capacity was estimated using a Swedish system for site quality  estimation  of  wetlands  after  ditching  (dikningsbonitering).  The  plot  with most  potassium  produced  after  fertilizationaproximately  in  level  with  theoretical estimations.  Key  words:  Peat  land,  Fertilization,  Ditching,  Growth,  site  quality..

Utveckling av en fiberberikad probiotisk fruktdryck

The purpose of this study was to investigate whether resistant maltodextrin is suitable as a fiber source in the probiotic fruit drink ProViva Mango without affecting the probiotic bacterium Lactobacillus plantarum 299v, viscosity or the sensory experience of the drink. Resistant maltodextrin is produced from hydrolyzed corn starch and is classified as a soluble dietary fiber. It is relatively resistant to digestion in the small intestine, where approximately 10% can be broken down, 50% can be fermented in the colon by the intestinal flora and 40 % is excreted in the faeces. Resistant maltodextrin has several important qualities when it comes to food processing. When added in a product, it does not affect the viscosity or taste and it is heat and acid stable.

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.

Konsumtion av livsmedel rika på järn och folsyra samt attityd till de näringsämnena & en hälsosam kost under graviditeten

BAKGRUND: Folsyra och järn är två viktiga ämnen som under graviditeten har olika betydelser dels för mamman och dels för fostret. Brister på dessa ämnen kan således leda till skador av olika slag och därför rekommenderas ofta kosttillskott till gravida kvinnor. Kvinnornas matvanor kan påverka om de får i sig tillräcklig mängd av dessa ämnen.SYFTE: Syftet med denna studie var att se hur gravida förhåller sig till att ha en hälsosam kost under graviditeten samt inställningen till kosttillskott med järn och folsyra. Studien syftade till att undersöka eventuella hinder samt se användningen av järn och folsyra.METOD: Studien är av kvantitativ typ med en enkät som inför denna undersökning har modifierats, Health and Taste Attitude Scale. Enkäten består av 7 frågor och 21 påståenden varav 6 st är från HTAS och resterande tillagda.

Förekomst av Helicobacter spp. hos hund : samband med hepatit/pankreatit?

To date, the genus Helicobacter consist of 26 different species and even more species are yet to be characterized. Helicobacter has been detected in connection with diseases in the liver and pancreas in humans and animals. Helicobacter spp. are gram negative, curved, S-shaped or spiral shaped bacteria. They are microaerophilic and have flagella that make them motile. Helicobacter, present in the gastric mucosa neutralize the gastric acid through production of urease that hydrolyses urea to ammonia and bicarbonate.

Granskning av drycker med hälsoprofil : påståenden och hälsomärkning

The aim of this study was to survey the labelling of drinks with pronounced healthbenefits found on the Swedish market today and to evaluate whether they are inaccordance to EU and national regulations or not. Especially the nutrition and healthclaims were looked into. This study shows that there are several drinks with claimedhealth effects being sold today. The process of approaching full functioningregulations in the EU on nutrition and health claims is proceeding slowly. A snapshotof today??s market of drinks with pronounced health effects shows that there aremultiple cases of misleading statements and interfering labelling on the products.Often it concerns nutritional labelling or health claims.

Undersökning av utökade användningsområden för Lotsbroverkets slam

Lotsbroverket is the largest wastewater treatment plant on the Aland Islands and it isdesigned for handling wastewater from approximately 30 000 persons. In 2011,Lotsbroverket produced about 2800 m3 of dewatered sludge. The sewage sludge that isproduced is transported to a contractor where it is processed to eventually be used e.g.in the construction of green space. This study aims to investigate available applicationoptions in terms of the sewage sludge that is produced in Lotsbroverket. The main aimis to study the feasibility of using the produced sewage sludge as a fertilizer in theagriculture of the Aland Islands.The sludge already fulfills limit values for heavy metals in accordance with the Act"The Aland Government´s directive on the use of sewage sludge in agriculture." Inorder to clarify the sludge content of pharmaceutical and organic substances it isrequired that the substances are identified and a risk assessment is performed.

INVERKAN AV HAVSF?RSURNING P? PROTONERBARA ORGANISKA F?RORENINGARAS EKOTOXICITET

Resulting from anthropogenic carbon dioxide emissions, average surface seawater pH is estimated to decline from today's approximately 8.05 to between 7.78 and 8.03 towards 2100. For ionisable organic pollutants, changes in pH can lead to a change in the degree of ionisation, which could influence the ecotoxicity of a compound by altering its bioavailability. In this study, potential changes in ecotoxicity of ionisable organic compounds resulting from ocean acidification are examined. This is achieved partly by conducting a literature review, analysing existing literature that investigates this relationship. Potential changes are also evaluated by examining marine ecotoxicity data for ionisable organic compounds on the watch list pursuant to Directive 2008/105/EC of the European Parliament and of the Council, as well as on the list of priority substances according to the 2022 proposal for amending the Water Framework Directive (2000/60/EC).

Soil carbon, pH and yield development in a long-term humus balance trial

Agriculture has to be performed in a sustainable way in order to sustain high yields and to support a globally growing population. Functional soil properties are fundamental for high yields and in order to achieve good soil conditions sustainable management is a key. Loss of soil organic material and increased soil acidity are problems associated with degradation of soils and hence less sustainable agriculture. In this thesis, the effect of different agricultural systems on soil organic matter, pH and yield was examined. The systems examined are a cereal system with straw removal or returning and a ley system, all with different nitrogen levels.

Evaluation of transgenic lines of field pepperweed (Lepidium campestre L.)

The worldwide industrial demand of energy, often in form of fossil fuel, is continuously growing and at the same time these resources are coming to an end (Hamamre, 2013). The interest and focus in renewable sources are then more important than ever and plants are suggested to be a good alternative for production of raw material for industrial purposes (Nilsson et al., 1998). But the world is also facing an increasing world population which also increase the nutritional needs, plants therefore need to be suitable for both industrial and nutritional purposes. To achieve this, common plants need to be improved but it also need new potential crops to be developed and introduced (Carlsson et al., 2009). Modern technology like gene engineering is an important tool to achieve these challenges (Carlsson et al., 2011). This work focused on analyzes and evaluation of different transgenic lines of field pepperweed (Lepidium campestre L.).

Soil fertility status and Striga hermonthica infestation relationship due to management practices in Western Kenya

Striga hermonthica, a parasitic weed, has long been believed to be correlated with the declining soil fertility status. However scientists have recently come to question this statement since some recent studies have shown contradictive results. To investigate whether soil fertility status and infestation of Striga hermonthica were correlated and the impact of it were caused by farmer management, 120 farmers in Western Kenya, where Striga hermonthica infestation is prone, participated in this study. In three districts with two sub-locations each, farmers answered a structural questionnaire and identified two fields, one with high and one with low soil fertility. These fields later came to be the basis for this study and soil were therefore also sampled from them.

Plantetablering och tillväxt för sådd och planterad tall 2-5 år efter markberedning med harv eller Huminmix-teknik inom Holmen Skog distrikt Norsjö :

The objective of this work was to compare the environmentally gentle soil scarification technique Huminmix (with possibilities to do track-grinding/HMMspår, long-scraping/HMMlångfläck and mounding/HMMhög) with conventional disc trencher, concerning seedling establishment and growth of direct seeded and planted Scots pine seedlings. Inventories were made during June and July 2005, in 34 seeded and 6 planted stands from 2000 ? 2004 (1- 5 years old) of lichen- and myrtillus/vaccinum-type in Holmen Skog AB´s district Norsjö in Västerbotten. The Huminmix-technique had been used for HMMspår in the seeded stands and for HMMhög in the planted stands (HMMlångfläck has been used from the year 2006 for direct seeding). The studied stands had been seeded with the same amount of seeds according to stand data.

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.

Emissioner i slutna utrymmen Med speciell inriktning på emissioner av formaldehyd och organiska syror

This study aimed to evaluate the levels of formaldehyde and organic acids that can build up within enclosed spaces. Another goal was to compare two types of paints that can be used as coating barriers within showcases and in turn compare them to the modern, and by many highly recommended, material of Marveseal®. A low volatile waterborne alkyd/acrylate paint and a two component polyurethane paint was compared to Marveseal® in two series of experiments. One series measured the level of formaldehyde, and thus the effectiveness of the three chosen barriers, and the other series measured the level of volatile organic acids, both the acids emitted from the paint itself, and that of the wood. One box in each series were not treated at all and was used as a reference.The fact that different types of materials emit volatile organic compounds have long been known.

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.

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