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258 Uppsatser om Mineral nutrients - Sida 6 av 18

Återföring av växtnäringsämnen från avloppsvatten till åkermark : en bedömning av intresset för nya näringsrika produkter

Sewage sludge contains plant nutrients and has earlier been utilised as fertilizer to cropland. Unfortunately not only plant nutrients but also heavy metals, pathogens and organic contaminants tend to accumulate in sludge. The suitability to use sewage sludge in agriculture has therefore been subject to several discussions over the years. The Swedish food industry does no longer accept sludge as fertiliser for Swedish producers. In 1999 the Swedish parliament accepted several objectives for environmental protection. In order to prevent environmental pollution and further exploitation of the earth crust, one of these objectives confirm that phosphorous from sewage shall be recirculated to arable land.

Laborationsmätning av vindtäthetens betydelse för en väggs U-värde

To fulfill the climate target that EU and the Swedish government have decided to apply, it becomes increasingly important that the energy efficiency of existing buildings and making new buildings energy efficient as possible. Of Sweden?s total energy consumption in 2011 was 40% used by residential and service. Of the 40% of the energy consumption was 60% used for heating and domestic hot water. A report from year 2012 shows that one reason why the heating volume is so great could be due to underestimating on the energy consumption for the heating in the planning of the building.

Val av tidpunkt för markberedning vid naturlig föryngring under skärm av Pinus sylvestris i Svealand : Timing of scarification when using natural regeneration in seed tree stands of Pinus sylvestris in Central Sweden

This thesis is built on a field study that was carried out in two seed-tree stands near by Götbrunna in Uppland, Sweden. The aim was to examine if scarification carried out in spring time could generate a more dense seedling establishment when using natural generation, than scarification carried out in autumn. It was also investigated whether there were differences in mortality the first season between the two plot-types. Plots were established block-wise with 50 blocks (pairs) on each site. The spring scarification was made with a hoe during 22-23 of April.

En jämförelse mellan amplifierad singelmolekylanalys och selektiv agar vid kontroll av hygienisering av avloppsslam

Bringing back the nutrients from the city to the country is becoming increasingly important, as the world?s stores of nutrients get more exhausted. Sewage sludge is an unapplied resource, rich in plant nutrients, which could replace parts of the commercial fertilizers used in Sweden today. Sewage sludge may contain large amounts of pathogens, such as Campylobacter and Salmonella, why use can cause severe spreading of infections, both to animals and humans. These pathogens have the ability to survive for a long time in soil and water and therefore some sort of treatment of the sludge is recommended before use.

Småvatten då och nu : en förändringsstudie av småvatten i Skåne och deras kväveretentionsförmåga

Wetlands play an important role in the ecosystem. They reduce the impact of flow flux in the drainage area, acts as upholder of biodiversity, as an esthetic and recreational component in the landscape and they have the ability to reduce nutrients such as nitrogen, and help preventing eutrophication in costal areas.The number of wetlands in Scania have, due to the intensified agriculture been reduced to maximize the area suitable for crops.However since the mid 80th the consequences of this has been acknowledged, and many wetlands have been restored.This master?s thesis aim to see what impact this development have had on wetlands in Scania over the last 60 years. And also look at some of those factors important for the efficiency of nitrogen removal in wetlands. During the process a detailed manual for inventories of this sort was created.The material used to execute the inventory of wetlands where aerial photographs over Scania from the 1940th, 1980th and 2000.

Förstudie: Förbättra detaljplanering hos Boliden Mineral AB

Boliden Mineral AB (Boliden) är Europas ledande metallföretag med kärnkompetens inom bl.a. gruvdrift och smältverk. Rapporten behandlar frågeställningarna kring detaljplanering (korttid resursplanering) och produktionsprocesser hos Bolidens underjordsgruvor; Garpenberg, Kristineberg, Renström och Tara.Gruvorna brottas med återkommande störningar av olika slag i produktionsledet vilket påverkar måluppfyllelse (planföljsamhet) för de fastställda veckoplanen. Företagets senaste tidstudie i Kristineberg visar att maskinernas utnyttjandegrad inte motsvarar förväntningarna och har en fallande trend. Tidstudien visar även att maskinfel utgör ca 40 % av totala störningarna.

Cultivation of Chlorella vulgaris in nutrient solution from greenhouse tomato production : a possibility to reduce nutrient levels and produce commercially interesting metabolites

The idea of using algae in different areas and exploring its possibilities is nothing new. Already in the early 1950s microalgae was explored as a possible food resource because of its high protein content. Lately there has been an increased interest in its potential for industrial use. Wastewater treatment is a possible use of algae since the algae grow well on the nutrients present in the water. This offers the possibility to grow algae for nutrient reduction and use the biomass for energy or animal feed since many alga species has a good nutritional value. Approximately 800-1000 m3 water is applied per 1000 m2 of greenhouse area during one season in a tomato production.

Val av komplementmaterial för våtkompostering av klosettvatten

Emissions of insufficiently treated wastewater, mainly blackwater (i.e. wastewater from toilets), contributes to the eutrophication of lakes and seas. At the same time, blackwater is a fraction with a low content of heavy metals and, after sanitization, it can recirculate plant nutrients to arable land using the liquid composting treatment method. Liquid composting means that organic material is degraded under aerobic conditions. For sanitization, the blackwater needs to be treated together with energy-rich complementary material.

Magnesiumstatus hos mjölkkor : en fältstudie

Magnesium is an essential mineral that is important for several physiologic and biochemical processes in the body. Deficiency of magnesium is mainly associated with grass tetany, but can also appear in cows during the indoor period. Since long it is known that potassium has a negative effect on the absorption of magnesium. Due to the fact that potassium fertilisation leads to a higher potassium content in forage, it is of interest to study interactions of potassium on the magnesium balance in dairy cows. There are few studies about magnesium feeding to dairy cows in Sweden and the purpose of this study was to investigate how much magnesium and from which feed-sources dairy cows in Sweden get their magnesium. Data was collected from seven farms in the northern part of Uppland and from seven farms in Skaraborg in Sweden.

Bättre enskilda avlopp i Sigtuna kommun : möjligheter för bebyggelse i Odensala socken

There are around 855 000 on-site sewage systems in Sweden and some 1 800 of these are located in the municipality of Sigtuna. The Sigtuna local authority has set the goal that all sewage systems with insufficient function should be improved before the end of year 2010. A malfunctioning on-site sewage system may cause three main problems: spreading of diseases, discharge of eutrophicating compounds and wastage of resources. The municipality strives to reduce these problems already at the stage of granting permits for installation of on site sanitation systems. The municipality has recently adopted new guidelines, which demands certain minimum reductions for different compounds. The guidelines also state that it is preferred that neighboring house-owners cooperate in jointly built and operated sewage systems and that the system should be able to recycle plant nutrients.

Studier av alkaliskt fosfatas och kollagen samt deras betydelse för skelettets mineralisering

There is convincing research which shows that the enzyme alkaline phosphatase (ALP) has a central role in the mineralization of bone, more precisely that its catalytic activity is needed in the process. ALP is found on the surface of matrix vesicles where the mineral is formed. One theory about the function of the enzyme is that it binds to fibrous collagen in the bone and thereby incorporating the mineral into the bone. The purpose of this study is to establish whether ALP binds to collagen. If this is the case, more elaborate studies around this will be performed.

Sliginmatning till rostugn

Outotec är världsledande inom mineral- och metallprocessteknologi och har genom åren utvecklat flertalet banbrytande teknologier för detta. Förutom teknologier inom mineral- och metallprocesser utvecklar också företaget innovativa lösningar för industriell vattenrening, användning av alternativa energikällor och teknologi för den kemiska industrin.I en av teknologierna, en rostugnsanläggning, används ett inmatningssystem för matning av kopparslig. Kopparsligen är nötande och fuktig som tillsammans med processgas, som innehåller arsenik, ställer höga krav på inmatningslösningen vad gäller funktionalitet och säkerhet. Inmatningen som används idag är, på grund av de höga kraven, en dyr lösning. Ingenjörer på Outotec misstänkte att en billigare lösning med liknande funktionalitet och driftsäkerhet kunde finnas på marknaden alternativt designas.

Att förebygga osteoporos i ett tidigt skede

Bakgrund: Osteoporos har under de senaste decennierna utvecklats till en av de stora folksjukdomarna. I Sverige drabbas cirka 70 000 människor av osteoporosrelaterade frakturer varje år och av dessa är det främst kvinnor som drabbas. Risken för att en svensk kvinna någon gång under sin livstid skall drabbas av en osteoporosrelaterad fraktur är 50 %. Hur snabbt en kvinna förlorar benmassan samt hur stor benmassa hon har från början är avgörande för om hon kommer att drabbas av osteoporos och därför är prevention i ett tidigt skede viktigt. Syfte: Syftet med litteraturstudien var att belysa preventiva åtgärder för premenopausala kvinnor som kan förebygga primär osteoporos.

Grundvattensänkning till följd av järnvägstunnel genom Hallandsås : miljökonsekvenser relaterade till förändrad kväveomsättning i mark

This thesis was carried out to give some background information to a report of SLU (Swedish University of Agricultural Sciences) for the Swedish National Rail Administration (Banverket). The requested information was to provide basic data for an environmental impact assessment of the construction of the tunnel through Hallandsås. The aim with the thesis work was to discuss and quantify the leaching of nitrate and the emission of nitrous oxide from the soil at the groundwater level established through the tunnel project. The nitrogen related processes that could be affected were described and discussed. The different areas where a decreased groundwater level can cause changes in the nitrogen processes are the wet and moist areas.

Kartläggning av föroreningars förekomst och spridning i Gräsötippen enligt MIFO

It is estimated that 22 000 contaminated areas exist in Sweden today. In order to classify the risk of contaminant migration from these areas and to prioritize which of these contaminated areas should first be treated, the Swedish Environmental Protection Agency (EPA) has designed a method, for the investigation of contaminated areas (MIFO). One of these contaminated areas is the landfill Gräsötippen outside Köping. The landfill has been used by both Yara AB and the Köping municipality between the years 1945 and 1975, and both industrial and household waste have been deposited there. The aim of this report is to survey which contaminants that can be found in the soil and water in the landfill Gräsötippen and to evaluate the migration of these contaminants.

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