Decomposition of organic matter is a critical process in the ecosystem, which involves many essential biotic and physical parts. Decomposition is therefore an important process both above and below ground. The rate of decomposition is dependent of many environmental factors for example: pH, moisture and supply of oxygen. The decomposition can therefore be affected by large scaled environmental influences, such as acidification and climatic changes. The root litter in the forest is in different ways affected by acidification, liming and manuering.

Organic animal husbandry has received a lot of criticism lately. The aim of this literature review was to examine if the rules and principles of organic pig farming give better or worse welfare in comparison to the conventional systems in Sweden. Health, physiology and behaviour have been used as indicators of welfare in this study. This is due to the importance of using more than one indicator in welfare assessments. Studies have shown that organic pigs have more remarks on joints when slaughtered, but these remarks can be reduced by vaccination against erysipelas.

In the coming years, organic food waste will be collected in the region of Gästrikland, Sweden. The collection is planned to cover the entire region by the end of year 2007. To start with, smaller amounts are being collected and transported to a central composting plant in Sala. However, a central composting plant in the region of Gästrikland is projected.The objective of this thesis is to evaluate a number of possible methods for composting of organic food wastes regarding their environmental impacts and localization.There are four scenarios for future composting of organic waste that have been evaluated. There are two that consist of membrane composting, either in Sala or in the region of Gästrikland.

GE Healthcare operates in Uppsala (Sweden) and develops systems, equipments and medium to purify medical substances. Discussions with the local authority concerning planed far-reaching changes and upgrades of the biological process techniques for sewage management, aroused the question about revising the terms of permit for the activity. Therefore it seemed necessary to evaluate a newly installed biological process technique, which is the background of this thesis. The evaluated biological treatment process was built in 2003 and consists of a biological reactor filled with moving bed carriers with a high surface area for biological growth. At the time of the project the biological wastewater treatment plant consisted of a flow equalization facility and two following parallel biological processes; a biological reactor with moving bed carriers and a tower trickling filter.The aim of this thesis was to survey the function of the biological reactor with respect to the reduction of organic matter.

To investigate effects of nitrogen on in-lake CO2 and CH4 production during winter, three pair of lakes was subject for a fertilizing experiment in which one lake in each pair was fertilized with nitric acid (HNO3) directly into the water column in the summer of 2012. The lakes in each pair are assumed to be morphologically, hydrologically and biologically similar, that is, the non-fertilized lakes are considered references. The pairs do differ in one major way by being progressively less humic, going from around 25 mg/l to 10 mg/l DOC. Sampling and analysis was carried out at the end of the frozen period in 2013. Results show a significantly higher concentration of both CO2 (p<0,001) and CH4 (?=0,1, p=0,053) between impact and reference sites in the two less humic pairs.

Käppala wastewater treatment plant situated on the island of Lidingö northeast of Stockholm is running a project during 2004 and 2005 with the purpose to map out the capacity of anaerobic digestion in the digesters that treat primary and excess sludge. The purpose of this thesis work, which is part of that project, was to characterize the present anaerobic digestion process and to investigate its capacity to treat other organic wastes such as restaurant waste and waste from water works. To decide the potential of both methane and biogas production from different substrates batch laboratory tests were carried out. To imitate the anaerobic digestion process at Käppala continuous tests with small scale reactors were carried out. These reactors were later fed with restaurant waste.The batch laboratory tests showed that primary sludge had a potential biogas and methane production of 0,62 and 0,35 Ndm3/g VS respectively after 40 days of digestion.

The biogas plant Kungsängens gård, owned by Uppsala Vatten och Avfall AB, produces biogas and biomanure from organic household waste, food processing waste and slaughterhouse waste. In year 2012, 4.4 million Nm3 of biogas were produced from 25 200 tons of waste. Before digestion all substrate is sanitized by one hour?s pasteurization at 70°C in order to kill pathogens. Another method, integrated thermophilic sanitation (ITS), is of interest in order to decrease the energy demand.

The producers of grain in Sweden are facing a rough future. The competition is getting harder all the time, in Sweden, in EU and also from the ?world market?. The producers have to be more efficient and have to have bigger units. Many producers might have to look for new alternative production opportunities.

This study was made on former agricultural areas that had been planted with spruce or pine, in the county of Västerbotten. The goal of the project was to investigate suspected deficiency of boron in these areas. Several objects have been reported for possible deficiency and some of these have the characteristic symptoms of boron-deficiency. The hypotheses are that 1) Boron deficiency is present at several of the investigated objects. 2) Planting of forest on cultivated postglacial sediments leads to a successive podzolisation with a decreasing content of organic matter in the mineral soil, due to decomposition, and a decreasing pH in the soil, even on locations that have been added lime. To be able to confirm or reject the hypotheses a number of tests were performed.

This study forms part of the R&D project "Improved survival of bird chicks in organic fields" managed by the Rural Economy & Agricultural society in Uppsala. The skylark (Alauda arvensis) is a species that has decreased drastically in Sweden as a consequence of more intensive cropping. Studies in England have shown that skylark reproduction can be greatly improved within conventional fields, at a low cost, by establishing patches of bare ground (skylark plots). Within conventional farming, herbicides can be used in case a weed problem arises due to implementation of these skylark plots, whereas this is not allowed in organic farming. This study examined the effects of skylark plots on the weed culture in organic autumn-sown (winter) cereals and whether weeds might cause long-term problems to farmers. The study was conducted in two parts; a field study and a review of the literature regarding the weeds observed. The field study was carried out in 2007 during three weeks in June and three weeks in July, on eleven organic fields with winter cereal in the vicinity of Uppsala.

One of Sweden?s sixteen national environmental objectives strives to decrease the impact on the climate. By 2020, green house gas emissions should be 40 % less compared to the levels of 1990 and a minimum of 50 % of the energy consumption should come from renewable energy sources. Because of this there is a great need of increasing the production of renewable energy. This is where biogas comes in as a competitive alternative.

The discussion about organic and fair trade products has been a big issue during the last few years. Despite an extensive knowledge about the environmental problems and a willingness to do something about it, the consumers are not always acting that way. Children do imitate their parents and other adults at an early age, so if the role models do not begin to act, think and dress ethically correct, neither will the children. Three problems have been identified out of the discussion. They relate to the questions of how older school children and parents of younger school children are taking sides regarding the organic/fair trade clothes and how existing trends in the society as well as those in fashion contexts influence their attitudes and consumer behaviour.

In a time when concern for the environment is a topic that is met with both love and hatred, organic goods and services become increasingly common on the market. Communication efforts with the purpose of increasing the proportion of organic products consumed are being conducted by both private and public actors. However, achieving attitudinal and behavioral change within complex areas such as this comes with many difficulties.Within public opinion change, a common way of achieving a change in behavior is to use fear appeals and scare tactics. Earlier studies have shown that messages prompting a low level of fear can be more effective than messages prompting a high level of fear, since a high level of fear tends to raise defense mechanisms in the consumer. The purpose of this essay is to examine whether fear and defense mechanisms is a problem when it comes to making consumers choose organic products, as well as studying whether messages prompting low levels of fear are more effective than those prompting high levels of fear.This quantitative study is conducted in the form of a questionnaire-based experiment, comparing the effectiveness of two messages prompting different levels of fear.

To value the risk and opportunity for our production in Sweden it is necessary to understand the marketing development for beef cattle production in the world. We have chosen to look at the Brazil beef cattle production. They are one of the biggest producers, have good opportunity to develop further and have a big affect at the world market. The method of our work is to gather information from experts of beef cattle production, located in Brazil. We have also gathered information through studies of literature. The factors that will have a big influence at the Brazil beef cattle production during the upcoming years is more efficient land use, lower age of slaughtering and extended use of feedlot-system. Our conclusion is that the Brazil beef cattle will have a sharp increase during the next five years. The amount of pasture will not change during that time.

Göteborg Energi has a surplus of district heating during spring, summer and fall. The heat surplus is due to a constant production of waste heat from oil refineries and heat from waste incineration over the year. It would be desirable to increase the demand for heat and the uptime for the newly built combined heat and power generation plant, Rya Kraftvärmeverk. One alternative could be to integrate Rya Kraftvärmeverk with a pellet production facility. By producing heat, electricity and pellet in a joint process the energy use can be decreased.