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59 Uppsatser om COD-fractions - Sida 4 av 4

Är kolrika jordar en källa till fosforläckage? : en sammanställning av data från 130 åkerjordar

Phosphorus (P) is an essential nutrient but a surplus could lead to eutrophication. Furthermore, the minerals used to produce the mineral phosphate is a non renewable resource. There are in other words several reasons to reduce the leakage of P and the agriculture is one important area to attend. The aim of this work has been to investigate if carbon-rich arable soils content contain more P than arable soils with low carbon content. Moreover it has been calculated if the carbon-rich soils could pose a risk of P leakage by comparing their delivery of P with the plant uptake. The work has consisted of compiling the results from former gathered and analysed soil samples of 130 Swedish arable soils. The fractions of P considered are water soluble P (Pw), ammonium lactate-extractable P (P-AL), hydrochloric acid-soluble P (P-HCl), organic ammonium lactate-extractable P (Porg-AL) and inorganic ammonium lactate-extractable P (Porg-HCl).

Metodik för bestämning av åkerdikens status : fallstudie av ett dike i Munktorps socken

Agricultural drainage ditches are links between fields, lakes and oceans, having the potential to transport e.g. sediment and nutrients. When in a good condition, drainage ditches can act as sinks for e.g. phosphorus and sediments and prevent eutrophication downstream. The aim of this study was to determine the condition of one agricultural drainage ditch and to come up with suggestions for appropriate measures. The aim was also to determine which of the ditch?s properties that were possible to evaluate visually, which processes they represented as well as which properties required complementary physical analysis. This in order to contribute to the work of developing a method for determining the status/condition of agricultural drainage ditches.

Ekonomi vid uttag av långa toppar som skogsbränsle i slutavverkning :

The market for biofuels from the forests have had a positive development and the job initiators for this master´s thesis wanted to examine the profitability of a method for harvesting forest fuel, which was unfamiliar to them. The method was the ?long tree tops-method?, here called the LT-method. The LT-method is characterised by the fact that timber is harvested as the only roundwood assortment while the rest of the stem, which in other cases would become pulpwood, is harvested as forest fuel together with the logging residues. The method is based on the assumption that advantages in handling of the forest fuel assortment such as increased load weights for forest hauling and truck transportation, should compensate for the lower price for pulpwood when sold as forest fuel. The aim of the study was to compare the profitability of the LT-method with the GROT-method (harvest of timber, pulpwood and logging residues) and conventional logging without any harvest of forest fuel, and aslo to try to identify factors affecting the profitability of the different methods.

Sustainable phosphorus management of horse paddocks at Julmyra

Horse keeping is gaining an increasing interest in Sweden. During 2004 to 2010 the number of horses increased with 10 - 20 %, and was estimated to be 362 700 in 2010. Julmyra Horse Center (JHC), situated in Heby municipality, is a gated community for people sharing a large interest for horses and a vision of a sustainable horse management has been formulated. This study evaluates how the horse keeping of today at JHC, and how an expansion of the horse keeping may affect the risk of enhanced phosphorus load to the nearby lake system Vansjön ? Nordsjön.

Habitat preference and dispersal of a sandassociated beetle, Apalus bimaculatus

Species that have a high degree of specialization and poor dispersal ability can be more prone to extinction than more generalist species and good dispersers. How these species traits affect the viability of populations is dependent on landscape factors,such as isolation and connectivity. Additionally, interactions between species (e.g. symbiosis), and how these interactions vary spatially and temporally can have a large impact on populations. When the range and habitat areas of a species continuously decrease, management strategies are often needed if the species shall be able to survive.

Miljösystemanalys av alternativa avloppssystem i ett urbant område ?Svartvattensystem : Skogaberg ? Ett pilotprojekt i Göteborg

Starting point to this Paper is the idea and wish to adapt the society and its different activities to a recycle society. A building area in Göteborg is planned and investigated for such adaptation. In the district named Skogaberg, about 130 households totally are planned from what 20 are blocks of flats. The idea with this project is to constitute an alternative sewage system, a Blackwater system, were the fractions of most nutrients and least pollution are separated, taken care of and utilised. The aim is to get a market and use the nutrients of the organic waste from the household in agriculture use.

Ärtrev som substrat för biogasproduktion : En litteraturstudie och rötning i labbskala

Until 2020, 49% of Sweden's use of energy must derive from renewable sources. Greenhouse gases must as well decline with 40% compared to 1990 as a part of Sweden's 16 environmental objectives. Biogas is part of the effort to achieve these objectives, but as the demand for biogas increases, more substrates are needed to meet the demand. The purpose is to investigate the conditions for pea residue as substrate by performing lab-scale mesophilic digestion with different fractions and notch lengths and then to summarize pea residue as a substrate for biogas production. During anaerobic digestion, 1000 ml bottles were used as reactors for digestion.

Att lära och undervisa om bråk med olika nämnare : En Learning Study i årskurs 4, 6 och 9

Syftet med den här studien är att undersöka undervisning och lärande av lärandeobjektet, bråk med olika nämnare, i årskurs 4, årskurs 6 och årskurs 9. Då specifikt jämförelsen av bråk med olika nämnare och addition med hjälp av gemensam nämnare. Studien avser att söka vad som är kritiskt för att kunna lära sig detta. Vi genomförde en learning study som är en typ av aktionsforskning där studien genomförs i klassrumsmiljö och fokus ligger på vad eleverna ges möjlighet att lära sig. Vanligtvis genomförs en learning study i tre cykler där undervisningen gradvis förbättras mellan cyklerna. Vår första cykel genomfördes i årskurs fyra, den andra cykeln i årskurs sex och den sista och avslutande cykeln i årskurs nio.

Utveckling av substratmixen vid Mosseruds biogasanläggning : Substratkartläggning och rötningsförsök i laboratorieskala

The world?s growing need for energy together with a desire to ward off the worst consequences of global climate change has resulted in a never seen desire to invest resources in renewable energy sources. Biogas production through anaerobic digestion is one of those growing energy sources. In Sweden there are over two hundred plants that uses this biological process to break down organic substances while producing carbon dioxide and the energy-rich gas methane.This master?s thesis has focused on development of the mixture of different organic substances that is treated at a specific plant, namely Mosserud biogas plant.

Undersökning av avfallshanteringssystem : För ett nyexploaterat område i Ekhagen, Jönköping

Outside of many Swedish households today, you will find a typical green wastecontainer. This container has not changed since its introduction, despitecomplaints about foul-smelling and its impractical system. Even if the system usedtoday, still is the most optimal choice, there is a lot of newly developedalternatives out there.Its purpose is to get a broader perspective on how a waste management systemcan be developed into a working, land efficiently and aesthetically pleasing systemof humans and the environment in a small residential area.The authors treat the residential area of Jära, Ekhagen, in Jönköping, which ismanaged by JM AB as a problem area in regards to waste management.The issues raised by the authors are the different waste management systems usedin the corresponding areas of the world, how to apply technical andenvironmental as well as the waste management facilities from financial aspects.In the process, the methods used were literature reviews, case studies and aninterview. The case study was done through a modeling of waste managementsystems in the area Jära and an interview was conducted with the company Envacworking with vacuum systems. Studies have been made by different systems n theareas around the world.The results show that using directives and guidance will reduce the environmentalimpact done without replacing the traditional system.

Anaerob psykrofil behandling av hushållsavloppsvatten i UASB : Utvärdering av kapaciteten hos en två-stegs UASB-reaktor för behandling av hushållsavloppsvatten

Hammarby Sjöstad is a new district in southern Stockholm. A main objective with the Sjöstad project was to halve the environmental impact compared to other construction work. The environmental goals involve a halved water consumption rate, a local treatment of storm water and trials aiming to extract nutrients from the waste water. Sjöstadsverket is an experimental treatment plant used for testing new treatment processes for domestic waste water from Hammarby Sjöstad. The results are to be compared with the conventional process used at Henrikdals treatment plant today.

Uthållig sanitet : en förstudie i staden Picota, Peru

The access to good sanitary facilities is an important factor that elevates the experienced living standard as it improves hygiene and reduces the transmission of deseases. The ratification of the millennium goals by 189 countries demonstrates that this is an important international issue. Together the countries have taken upon themselves that the proportion of the population that lacked access to sustainable safe drinking water and sanitary facilities in the year 2000 will have been reduced by half by the year 2015. In Peru, the construction of sewage pipe networks to transport the sewage out of the direct human environment is progressing. The safety and sustainability of these systems can be questioned, since in Peru the sewage seldom receive any treatment before being emitted to a recipient. This is taking place in Picota and sorrunding villages as well. In the last 25 years several systems implementing small-scale onsite treatment have been introduced throughout Latin America in an attempt to give more people access to sustainable and safe sanitary facilities, reducing water consumption and taking advantage of the agricultural values of the sewage fractions while protecting the environment from its negative impact. In this study three different sanitary systems and the effects of different population growths were compared.

Marktäckande, lågväxt vegetation på ställverksmark : en biologisk bekämpningsmetod mot ogräs

Unwanted vegetation on the land of electric transforming stations is a problem, in the sense that it contributes to higher fire risks and also constitutes an obstacle for people performing maintenance operations at the station. Such unwanted vegetation is controlled using herbicides and mechanical measures. Since the use of herbicides implies environmental hazards, there is a need to find alternative ways of fighting the unwanted vegetation. Investigation into suitable plants for ground cover, trials in the greenhouse, trials in the field, soil analyses and compilation of experiences from similar trials are parts of this work. The paper also contains analyses of possible environmental benefits and economical gains. There is also a final discussion of some proposals regarding alternative weed controlling methods.

Om fototextpoesi : Läsningar av mötet mellan fotografisk bild och poetisk text

What is the relation of image and word, of sentences and pictures? What kind of message does this combination produce when juxtaposed on a single material plane? And how do we read its ?infinite? relation? These are the questions at the center of this inquiry. My main interest concerns the exact nature of the relation between photographic images and textual elements of poetic language when these are juxtaposed in what I call Phototext poetry.The thesis calls into question the conventional reading habits of the conjunction of photographs and texts, and seeks to understand the more complex connections intrinsic to the relation image/word and its material and perceptual play in poetic works. Does a text always ?anchor? the multiple meanings of an image, as Roland Barthes argues? What if the alterations of an image could ?anchor? certain fractions of a poetic, polysemantic textual construct? Is a photograph indifferent to the visual, material permutations of texts that certain contemporary poetic practices produce?I discuss phototextual works and collaborations of various kinds, from Molin fontän [?Molin?s fountain?] (1866) over classic surrealist poetry to language-oriented writing.

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