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1020 Uppsatser om Soil parameters - Sida 21 av 68

Frigörelse av fosfor från färskt, fryst och torkat växtmaterial : ett laboratorieförsök för att öka förståelsen för fosfordynamiken inom växtodlingen

Phosphorus is the single most potent contributor to eutrophication of freshwater and has also been shown to contribute to the toxic algae blooms in the Baltic sea. The dynamics and paths of losses of phosphorus from arable lands are not fully understood. It is known that phosphorus can be lost directly from plant material to water. In studies where plant material has been subjected to several freeze-thaw cycles, large amounts of phosphorus have been lost. Most studies have been conducted under field conditions, with many factors effecting the measured losses of phosphorus, such as weather and type of soil. This study was performed in a controlled environment without the presence of soil. Instead of soil, small glass beads were mixed with the plant materials in vessels, to make possible homogeneous leaching with water through the mixture of glass beads and plant materials. In this study, clover, ryegrass and dry straw were cut to pieces, approximately 2 cm long.

Ha?llbar sockerro?rsodling fo?r etanolframsta?llning i Brasilien : Hur slagkraftig a?r dagens ha?llbarhetscertifiering och kan den fo?ra?ndra mark- och vattenpa?verkan fra?n odlingarna?

Climate changes today are mainly caused by anthropogenic activities and the increased emissions of greenhouse gases to the atmosphere and this has raised questions on how to reduce the usage of fossil fuels. Ethanol is a good alternative to conventional gas and has been used in Brazil since the 1970 ?s. In Sweden several newspapers has written about the poor working conditions on many farms thus making the Swedish company SEKAB design a certification for their ethanol to ensure that it can be considered to be a sustainable alternative.Furthermore WWF has developed a certification tool called Bonsucro in cooperation with Coca Cola, Ferrero group, BP and Shell. This is due to the fact that no global certification tool has been available up until now.

Irrigation scheduling for efficient water use in dry climates

In this report the importance of irrigation scheduling in dry climate is shown, how it can save water and energy; how this method can improve crop yield by supplying the right amount of water at the right time. It is shown how irrigation scheduling and irri-gation technology together increase the irrigation efficiency..

Inverkan av nederbörd, temperatur och frost på årsringens egenskaper hos boreal tall (Pinus sylvestris L.) :

The wide distribution range of our boreal pine (Pinus sylvestris L.) provides a great variation in growing conditions and climate/weather factors that influence the wood development of the trees. A great number of extensive studies have been conducted over the years in order to clarify growth trends of this and other species over more or less wide-ranging areas. In this thesis effects of weather factors were instead compared between different forest stands from the about same geographical location. The effects of precipitation, temperature and frost on the year ring characteristics of pine were studied in the research forest of Svartberget Vindeln, in northern Sweden. The stands differed in site index and silvicultural treatment; fertile ? high stem density, fertile ? low stem density, poor ? high stem density and poor ? low stem density.

Beräkningsmodell för massbalanser för Slottshagens reningsverk

In the next few years the pollutants loading at the Slottshagen wastewater treatment plant in Norrköping is going to increase due to the reason that one of the waste water treatment plant in the district will be shut down.A survey of how these different pollutants are divided in the treatment process is therefore necessary for mapping out both the loading and treatment efficiency.This can be achieved by studying mass balances.Mass balances were carried out for the water treatment process for the mechanical/chemical,biological and the chemical stage.The mass balance studies show that the treatment efficiency was very good. However in order for the mass balances to be quite consistent and to ensure complete coverage of results and conclusions i.e. more reliable results, sludge samples should be collected and taken at different times per day and the influent rate should be investigated.In this work mass balance has been set up in order to illustrate and identify the factors that should be considered and taken care of for further estimation using mass balances in the future. Furthermore this survey results in a calculating model for the mass balances at thisplant.This calculating model is used as a tool to facilitate future calculations for mass balances for the water treatment process at Slottshagens wastewater treatment plant.Moreover it provides a basis for carrying out further estimation of the treatment process in the near future.In this project the importance of some operating parameters was also taken in consideration.This calculating model can be modified so that calculations of such operating parameters i.e. sludge loading and sludge age can be easily performed.Such information can be used further to evaluate different operation alternative in order to ensure an optimal use of the treatment process with in the plant..

Utlakning av tungmetaller från Skörby deponi

The purpose of this thesis has been to assess whether leaching from one particular Swedishlandfill site, Skörbytippen, is contributing to elevated levels of heavy metals in a ditch runningfrom the landfill site to the lake Mälaren in the communal region of Håbo kommun. Since theditch is stretching approximately five km downstream from the landfill site, in situ observationsand maps with known points of inflow was utilized to determine appropriate test points for thecollection of samples.Soil, water and sediment samples were collected and analyzed for content of organic material, pHand conductivity. Data on plant-available elements and total amounts of heavy metals wasacquired through ICP-analysis.The results show that the Skörby landfill is currently in the methane-forming anaerobedevelopment phase, which indicates that the concentration of free and complex-bound metals inthe leachate water should be low due to chemical binding with other landfill compounds. The pHof the sediment samples was generally one unit higher than the soil samples and some of themeasured data, such as pH and conductivity, show that an environmentally disturbing dischargeof some kind of strongly alkaline chemical(s) has been made from Benders? takpanneindustri inclose proximity to the landfill.

Geoteknisk bärförmåga hos borrade injekterade pålar i åsmaterial Fältförsök: Slussen i Stockholm

This thesis describes the redesign ofequipment designed for drying bags thatis used in Fresenius Kabis´manufacturing of their nutritionmedicine in Uppsala. The need of thistask arise during the start of thedevelopment of a new packaging line werethis equipment were meant to be used. Anevaluation of the bagdryers capacity andcapability was necessary.The work started with gathering ofinformation from suppliers of the usedcomponents and from the responsibleengineers for this equipment. Aneducation to learn how the equipmentworked and how to operate it were taken.That was followed by the creation of astudy plan were the tests were plannedto test different parameters effect onthe drying result and to see if thebagdryer managed to handle the bags ofthe correct format in the pace that theequipment should be designed for.The test results detected a need ofdesigning a unit with a function thatholds the bags in place while passingthrough the dryer in order to attainhigh quality results. The results werelater used for optimization of thedesign.

Inverkan av transgena grundstammar på fruktkvaliteten hos icke-transgena äppelsorten ?Jonagold?

Gene technology has become more and more attractive in plant breeding during the last twenty years. This is probably because it can readily improve the existing commercial cultivars that have only one or a few drawbacks by modifying one or a few genes without changing the main genetic constitution. In this regard, gene technology is more effective than conventional breeding.The aim of this project was to analyze the fruit quality of the non-transgenic apple scion ?Jonagold? grafted on non-transgenic and rolB-transgenic apple rootstocks. The rootstocks used were M9-rolB1, M9-rolB2, M26-rolB and non-transgenic controls M9 and M26.

Radioktivt cesium (Cs-137) i vildsvin (Sus scrofa) från Tjernobyldrabbade områden i Sverige

In April 1986 an accident occurred at the nuclear power station in Chernobyl. Radionuclides were spread all over Europe including Sweden. Today there are still measurable concentrations of 137Cs in the different ecosystems in the contaminated parts of Sweden. The wild boar is the second most popular game in Sweden and today the Swedish population consumes more wild boar meat than ever. As the wild boar population increases the wild boars are moving further north towards the contaminated areas, which creates an interest to study the state of 137Cs in wild boars in these areas. Muscle samples from wild boars collected during 2010-2013 were analyzed based on 137Cs content.

Metadon till hund : klinisk farmakologi

Methadone is frequently used as an analgesic drug for dogs although there are very few studies describing the pharmacokinetics of methadone in this species. In man methadone has a long half-life and there are considerable differences in pharmacokinetics between individuals. The dose interval is lengthened when the drug is used fore longer periods of time due to prolonged half-life. Therefore the drug dose must be adjusted individually. The purpose of this study was to study the fundamental pharmacokinetics of methadone in dogs, and to find an optimal drug dosage.

Fröplacering vid hög såhastighet - Väderstad Rapid jämfört med Amazone Cirrus

In today's agriculture efficiency and the capacity of tools and machinery are crucial. In this work we investigate whether it is possible to enhance the capacity of sowing by increasing the work speed of seeders, how seed technology affects seed placement, and if there is any difference between two different brands of seeders and their sow techniques. The seeders we have chosen to compare are Väderstad Rapid drill and Amazon Cirrus drill. The tillage capacity of the seeders and their traction power needs were examined as well.Väderstad Rapid and Amazon Cirrus were tested in a randomized block design with four replicates at three different speeds, 8 km/h, 12 km/h and 15 km/h. The seed placement at the different speeds was examined by dividing the seedbed into four different zones from its surface to its bottom.

Validation of Steins/Arla Foods method for lactate fermenting clostridia in milk

One of the most serious and economically important defects caused by clostridia in milk products is the late blowing of semi-hard cheeses.Clostridia occur naturally in soil and can contaminate milk through crops contaminated by dung and soil followed by a less successful silage process, that give them opportunity to grow unaerobically. When anaerobic conditions occur, such as storage of semi-hard cheese, they ferment lactic acid to butyric acid and the gases CO2 and H2.At the fusion of Arla and MD Foods, a series of changes were conducted on the MPN method for lactic acid fermentation for clostridia in milk. These changes resulted in an increased accuracy due to an increased number of test tubes and the change of media from MRCM to BBB, Bryant & Burkey Broth, that was thought to be more selective for Cl. tyrobutyricum, the organism mostly found in hard cheese. When the number of dairy farmers that were given quality reduction fines increased, the new method was suspected and a validation was conducted.The validation included inoculation of different clostridia and bacillus strains into BBB substrate and enzymatic testing of positive samples with Rapid ID 32A.

Årstidsdynamik för kvicksilver i ett sövattensediment :

The limit for mercury in fish, set by health authorities, is exceeded in about half of the lakes in Sweden. Methyl mercury (MeHg) is the most toxic form of mercury and accumulates in fish. Therefore transformation of inorganic mercury (Hg) to methylmercury (MeHg) is an important process that we need to understand in order to possibly counteract the negative effects of mercury in the environment. The seasonal dynamics of mercury biogeochemistry is likely of great importance for the accumulation of MeHg in the aquatic food web. In thesis the chemical speciation and transformations of Hg and MeHg in bottom waters and sediments is followed in Ängessjön, a small lake located on the east coast in the middle of Sweden. The lake is not directly affected by any industrial pollution and concentrations of Hg in the sediment reflect the atmospheric deposition in this area, as well as processes taking place along the hydrological pathways from soil to lake. Samples from sediment, bottom- and streamwater were collected in average every second month during the period Feb.

Inventering och riskklassning av förorenade områden i Öna och Östnor :

This work consists of a survey and risk classification of eleven metal industries including foundries, finishers and engineering industries in two industrial areas in Mora. The study follows a method called MIFO (Method of Surveying Contaminated Sites) composed by the Swedish Environmental Protection Agency. In the method assessments of the degree of hazard posed by the pollutants, the level of pollution, the conditions of dispersal, sensitivity and the degree to which the area is worthy to protect are made for each contaminated site (object). The assessment classify the objects into four risk classes in which risk class 1 denotes a very large risk, 2 large risk, 3 moderate risk and risk class 4 little risk. The work of surveying using MIFO is divided into two phases.

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.

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