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939 Uppsatser om Plant nutrients - Sida 58 av 63
Tetratermmodellering och regressionsanalyser mellan topografi, tetraterm och tillväxt hos sitkagran och lärk : en studie i norra Island
This study was made in an attempt to give the forest research centre Mógilsá a producedtetratherm map and a better understanding of how topography and temperature influencethe growth of two tree species. The digital tetratherm map model, covering the northernpart of Iceland, was developed to investigate the correlation between tetratherm and thegrowth of Picea sitchensis and Larix (sukaczewii + sibirica). The study confirms theusefulness of digital terrain models in providing data for a lot of different factors and forthe tetratherm model. Hopefully will this tetratherm map be used in future studies.Secondly, investigations were made correlating the growth of the two species againsttopographic factors representing height above sea level, distance to the sea, slope andtopex. Thirdly, investigations were made comparing the aspect and the ground shape tothe growth.The growth rate of Larix had strong significant correlations to the tetratherm and thedistance to the sea- factors.
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.
Towards sustainable rye cultivation : soil carbon and yield modelling for crop rotations with rye
Using the Introductory Carbon Balance Model, ICBM, five different crop rotations with rye
1. Rye-Ley-Ley-Rye-Beans-Rye
2. Rye-Rye-Rapeseed-Rapeseed
3. Rye-Ley-Ley-Rye-Potatoes-Rye
4. Rye-Rye-Potatoes-Wheat
5. Rye-Rye-Potatoes-Beans-Wheat-Rye-Potatoes-Rapeseed
were tested theoretically in four different cultivation scenarios
? Straw left on the field, biogas digestate added as fertilizer. Labelled ?+straw+BD?.
? Straw left on the field, only synthetic fertilizer. Labelled ?+straw-BD?.
? Straw harvested, biogas digestate added as fertilizer.
Riskbedömning vid Saltvikens kopparverk
AbstractAt Saltvikens copperindustry, which is located in the municipality of Oskarshamn, copper was refined from sulphiteore some hundred years ago. The ore underwent several steps in the process before the final product was received. These steps all had an influence on the environment through discharge of heavy metals. The area where the copper industry was located is today considered to be of specific national interest due to its valuable nature and cultural values, as well as its value for recreational outdoor activities. Therefore, it is important to determine the present level of contamination and if any transport of contaminants have occurred, and to identify the risks that are associated with the site both at present and in a longer time perspective.Thirtynine soil samples and 16 sediment samples have been analyzed.
Betula : arter och sorter
As birch is one of the most common trees in Sweden, and probably one of the easiest for
someone who lives here to identify, it is interesting to note that most people do not know
how variable the genus is and how widely it is distributed across the northern hemisphere.
One can find birch growing at both high and low elevations, demanding different soil
conditions and preferring varying amounts of sunlight. Many people may also be surprised to
hear that the colour of the bark can vary from bight white to almost black, and different
shades of pink, orange and red can also be displayed. This, together with the astonishing
beauty of the genus, the important role as a pioneer in many ecological systems and the
difficulty in sorting out the taxonomy of the genus, constitutes the background of this thesis. The thesis is written at the Department of Landscape Development in Alnarp, Sweden with Kenneth Lorentzon, researcher at the Swedish University of Agriculture as a supervisor. The aim of this thesis is to highlight which species and cultivars within the genus Betula could be appropriate for horticultural use in Sweden.
Vindkraftsturism : En studie av teknisk turism med särskilt fokus på vindkraftsparker
This study investigates and describes the phenomenon of ?technical tourism?, in the case ofwind power plants in Sweden. The main purpose of the study is a greater understanding ofa field which to date has remained largely uncharted.Technical tourism is a type of visits to a production site, where the technical aspect ofthe production is the main focal point for the visitor. The definition of technical tourism isbased on concepts within ?Industrial tourism?.
Utvärdering av olika sätt att hantera avloppsslam i Värmdö
Important issues for the local authorities are what to do with the sludge produced insewagetreatment plants. The tax for landfill leads to higher costs with 250 SEK/ton. On the 31December 2004 it will be forbidden to landfill sludge.In Sweden the yearly production of sludge is 240 000 tons, counted as DS. The phosphorouscontent is 3 % in sludge. The total yearly production of sludge gives 6000 tons of phosphorous.
Removal efficiency of perfluoroalkyl substances (PFASs) in drinking water : evaluation of granular activated carbon (GAC) and anion exchange (AE) using column tests, and the effect of dissolved organic carbon
Poly- and perfluoroalkyl substances (PFASs) are a group of environmental contaminants that have gained increasing attention due to their potential to bioaccumulate, environmental persistence and potential toxicity. PFASs have been found in surface water, sediment, air, soil, sludge and ice caps globally, as well as in wildlife and humans. Furthermore, PFASs have also been detected in drinking water, leading to raised concerns for human health, since drinking water is one of the most significant sources of PFASs for the general population. Conventional water treatment techniques have shown to be ineffective removing PFASs, highlighting the importance for further research to develop efficient removal techniques.
The aim of this study was to investigate the removal efficiency of PFASs in water using two treatment techniques; granular activated carbon (GAC), type Filtrasorb 400®, and anion exchange (AE), type Purolite A-600. Additionally, the effect of dissolved organic carbon (DOC) on removal efficiency was studied.
Energieffektivisering i ett reningsverk för skogsindustriellt avloppsvatten genom förfällning av extraktivämnen
Pulp- and papermills expend vast amounts of water in order to produce pulp, paper and cardboard. Hence, they alsocreate vast amounts of waste water which has to be cleaned before it can be released into the receiving body of water. Insuch a wastewater treatment plant, tremendous amounts of energy are expended by the aeration in the biologicalcleaning process. This aeration is necessary to supply the microorganisms that shall decompose organic material withoxygen, which they need for their metabolism. The transfer of oxygen from the gas phase to the liquid phase isprimarily inhibited by surface-active substances in the waste water like resin acids or fatty acids.
Felbegreppets tillämpning på skogsplantor
Uppsatsen behandlar felbegreppets tillämpning på skogsplantor. Lagstiftningen inom området skog och skogsplantor är relativt omfattande men skogsplantor är biologiska produkter varför lagstiftning inte helt kan förhindra att skador eller sjukdomar ändå uppstår. Det är helt enkelt inte möjligt att framställa skogplantor utan att en viss andel av dem är behäftade med fel. Då det är en mängd sammanverkande faktorer som kan bidra till skador eller plantors död kan det vara svårt att fastställa om orsaken till skadan/plantdöden var att hänföra till plantorna eller faktorer i uppväxtmiljön. Svårigheter att fastställa orsaken kommer därför bidra till svårigheter för skogsägarna i samband med reklamation.
Landskapsarkitektens yrkesroll i Sverige och Spanien : en jämförelsestudie mellan svensk och spansk landskapsarkitektur med platsexempel från Stockholm och Barcelona
Landscape architect is a profession that withholds varying tasks inside countries and between countries. In many countries the landscape architect profession does not exist. Spain is a country where the landscape architect profession is not recognized, and the professions that work with landscape architecture are architects, engineers, biologists and agronomists. "Paisajista", in English "Landscaper," is in Spain a common name for those who design gardens and parks. Sweden is one of the countries with most landscape architects due to its population and the profession is well established.
Förutsättningar och Avsättningar för Biogas för Gröna Vessigebro : Version 1.0
The community Vessigebro, in Falkenberg and its surrounding areas housing one percent of all dairy cattle and two percent of all pigs in Sweden. This means that there is a large amount of manure as a basis for producing biogas in the area. A number of farmers have therefore formed a cooperative named Vessigebro biogas and started the project Green Vessigebro, with the goal of creating the conditions for a more profitable and more sustainable agriculture production.The study deals with the conditions and sale opportunities of the feasibility study Green Vessigebro. The study has looked at the work that was previously carried out for the biogas that could be produced on the farms in Vessigebro, The main pipeline for natural gas on the Swedish west coast and its operators, the Swedish Competition Act , Electricity Act , Natural Gas Act, the District Heating Act , Sustainability Act , previously proposed measures, municipality interest in biogas from Vessigebro , possible collaborations, possible sale opportunities and perform calculations with data from the municipality Ljungby for a suggested transportation of biogas between Vessigebro and Ljungby.The study shows that there are several interesting sale opportunities for biogas from Vessigebro. The production and use of biogas in Sweden is increasing and the trend seems set to continue.
Framtidslayout för Motala Wire Work
This master thesis was conducted at Motala Wire Works Ltd (MWW) in Motala during the autumn and winter of 2007-2008. The thesis named ?Future layout of Motala Wire Works? focuses on making a better planed layout for the factory, which also take in to consideration future changes.Motala Wire Work produces wire mesh products of varying sorts for the white goods industry. The factory was started by Electrolux during the 1950?s.
Produktutveckling och prestandatest av ett vattenvärmedrivet torkskåp : Jämförelse mellan tre utvecklade versioner av ett vattenvärmedrivet torkskåp
AbstractElectricity consumption is a globally increasing problem caused by the high share of electricity produced in coal power plants. These contribute to high carbon emissions when only about 1/3 of the heat generate electricity and the remaining 2/3 of the heat cools off. Combined heat and power plants (CHP) have high efficiency because they use the residual heat for domestic heating. The CHP plant often use fuels from renewable resources, giving them a lower carbon footprint, but are also depending on the heat demand. If electric powered products such as drying cabinets convert to heat powered products more environmentally friendly electricity will be produced by CHP plants, which can supplant electricity, produced from coal power plants and reduce carbon emissions.
Biogaspotential hos våtmarksgräs
BIOGAS POTENTIAL IN GRASSES FROM WETLANDSMarvin MartinsThe purpose of this study has been to survey wetlands that are suitable for mowing and to analyze the biogas potential in the harvested grasses. A preformed investigation showed that there are suitable wetlands, which can be harvestable, namely those mowed formerly in traditional haymaking. The practice of traditional haymaking is dying out in Sweden today but there are several good reasons why it should to be reconsidered. Nature- and cultural values are obvious, also the unutilized energy in the grass.The suitable types of wetland that were specifically studied were the productive wetlands; meadow marshes and wet meadows. These wetlands are represented in the Swedish meadow- and pasture inventory database; (TUVA) and the Swedish national wetland inventory (VMI).