Every year about 210 000 tones dry weight of sewage sludge is produced in Sweden. Most of the sludge is applied to agricultural land, plantsoil and landfill cover. Sewage sludge contains essential nutrients such as nitrogen and phosphorus. Nitrogen is limiting growth on solid ground in Sweden and can therefore be used as fertilizer to increase productivity. In order that the sludge can be spread to forest land it requires first a conversion of sludge to pellets, to make it more manageable.

?Are the headwaters streams at the right position in the map? is a study that has been performed on behalf of Holmen Forest, region Örnsköldsvik. This study will be the basis for deciding if the Hydrology Layer Property map or Holmen Forest map will be used for planning nitrogen fertilization in forestry. The background to this study is that nitrogen fertilization near water will increase the risk of nitrogen leaching out into the water systems, which has a negative impact on the environment. The headstreams positions have been recorded in the field with a GPS and the data analyzed in the geographic information system ArcMap.

Nitrogen deposition leads to environmental damage in areas where the nitrogen deposition is high. Southwest Sweden receives an annual nitrogen deposition of up to 20 kg N/ha. Nitrogen that is not assimilated by the vegetation is accumulated in the soil, which may lead to nitrogen saturation and an elevated risk of nitrogen leaching. Nitrogen leaching from forest areas in southern Sweden has proven to be higher than from agricultural areas, which have been thought to be the main contributors to elevated nitrogen levels in rivers and lakes. The amount of nitrogen that leaches depends on the fraction of the total nitrogen in the soil that consists of nitrate, since nitrate is easily transported through the soil.

Syftet med denna studie var att kartlägga retentionen av resinbaserade fissurförseglingar på sexårsmolarer utförda på studentklinik. Karies registrerades även på övriga sexårsmolarer. Materialet utgjordes av 51 barn födda år 1999 eller 2000 med minst en fissurförsegling på sexårsmolaren utförd av tandläkarstudent. Fissurförseglingen skulle vara utförd i Delton® och ha en minsta uppföljningstid på ett år. Data registrerades från journaler avseende allmänhälsa, medicinering, kariesdata och riskgrupp.

The main project Dry preservation of source-separated organic household wastes involves a new technique for treatment of biowaste through drying. Investigations are going on to determine how the dried biowaste best can be used to close the natural circular flow of nutrients. The objective of this degree project is to determine if the dried biowaste can be used as a soil conditioner. By restoring the nutrients in the material to the ground, the natural circular flow is closed. A declaration of contents, including the nutrient levels, C/N ratio, pH and the electrical conductivity of the dried biowaste, was constructed and a germination test was done to make sure that the material did not inhibit sprouting.

Today green tree retention, together with leaving dead wood, is a common practice with the aim to reduce negative impacts on biodiversity and environment due to clear-felling. To better understand whether this conservation practice also makes a long-term difference, it is important to know what happens to these trees after harvest. Few studies have made an assessment of what happens to retention trees over a longer time period. In this study I inventoried retention trees that were left at clear-cuts six, twelve and eighteen years ago. I carried out a re-inventory of 57 retention patches (divided into free-standing tree groups, small swamp forests and edge zones) and free standing dead trees, spread over 25 previous clear-cuts in central Sweden.

An increasing demand for wood products in China has resulted in large areas invested in fast-growing tree plantations of eucalyptus. Eucalyptus plantations are often associated with an intensive management including fertilization. By understanding the effects of fertilization and where in the ecosystem nutrients are accumulated a more sustainable forest management could be achieved. In this study, a nutrient budget including all biomass and soil components was created for Eucalyptus urophylla. The examined nutrients were nitrogen, phosphorus and potassium.

The aim of this literature study was to analyze how milk urea concentration is working as a measure of the nitrogen supply to rumen microbes and indicator of the environmental load. Questions included in this literature study were how to improve the dairy cattle nitrogen efficiency and what correlations there are between milk urea, nitrogen efficiency and crude protein content in the feed. Effects on the reproduction from high ration protein content are also addressed. Dairy cattle are today fed with large proportions of protein which could lead to high expenditure of feed and environmental pollutions. The nitrogen can be lost to the environment by different pathways; leaching, denitrification or by emission to the air.

The aim of this literature study was to analyze how milk urea concentration is working as a measure of the nitrogen supply to rumen microbes and indicator of the environmental load. Questions included in this literature study were how to improve the dairy cattle nitrogen efficiency and what correlations there are between milk urea, nitrogen efficiency and crude protein content in the feed. Effects on the reproduction from high ration protein content are also addressed. Dairy cattle are today fed with large proportions of protein which could lead to high expenditure of feed and environmental pollutions. The nitrogen can be lost to the environment by different pathways; leaching, denitrification or by emission to the air.

The aim of this report has been to investigate the use of electricity energy before and after a conversion of foodservice. The ambition was also to highlight the food safety and the retention of nutrients in relation to the conversion. The methods being used were qualitative interviews, case studies, study visits and literature. The equipment and the use of energy was the same in 2008 as in 2011 for hot-holding of the tested component, sauce with ham. The chilled system used more than three times the energy and cost for one portion than one portion in the hot-hold system.

The purpose of this study was to examine whether urea could be an option as a nitrogen source for young cattle, the study was limited to risks related to feeding, growth and feed efficiency. Microbes in ruminants have the ability to convert nitrogen to protein, this has been highlighted by beef producers as they are in search of cheap protein feed resources. Urea can be a worthy source of nitrogen for growing young animals, because of its high nitrogen content and the low price. Studies have shown that the replacement of a portion of the total protein content by urea in diets with low content of crude protein, like corn silage, may improve animal growth and feed efficiency. Replacement of all the true protein with urea can result in reduced feed intake and microbial growth.

Employee turnover can cost an organization a significant amount of money. In addition, retention of employees can beneficial towards to an organization as it e.g. allows to save costs related torecruitment and training of new employees. The fast food industry is recognized as an industry which employs low-skilled employees and is especially in the United States known to be prone to high employee turnover. With regards to Europe, only little information is available in the field of low-skilled employee retention in the fast food industry.

The aim of this thesis is to improve the control of urea injection at the combined power and heating plant Framtidens Gärstad (FTG). Tekniska Verken i Linköping AB is the owner of the plant.The FTG plant consists of a boiler where garbage combustion is done. From the combustion nitrogen oxides are emitted. These nitrogen oxides are hazardous to the environment. To reduce the nitrogen oxides, injection of urea into the boiler is used.

In a column experiment the effect of three different biochars on nitrous gas emissions, nitrogenretention and water filled pore space (WFPS) were studied in a Swedish sandy soil, classified as aCryopsamment. Ammonium retention was positively correlated, while KCl-extractable ammoniumwas negatively correlated, with the specific area of the biochars. The question was raised whether thenegative correlation between extractable ammonium and biochar specific area reflects the amount ofammonium present in the soil or its extractability from the biochar, and whether methods forextracting soil mineral nitrogen, like KCl-extractions, have to be modified for application on biocharamended soils. There was a tendency of increased nitrate retention and KCl-extractable nitrate withbiochar and KCl-extractable nitrate was positively correlated with the specific area of the biochar. pHwas higher for all biochars compared with control, although the differences were not significant, andWFPS was lowered by biochar addition, significantly in one case.

This study was carried out at the Swedish University of Agricultural Sciences, Dept. of Agricultural Research for Northern Sweden. The aim of the study was to determine how plant species richness and diversity influence the nitrogen pools and nitrogen fluxes in the soil. Plant and soil samples from a biodiversity experiment in grasslands were used. Thirty plots with 12 grassland plant species (legumes, grasses, and non-legume herbs), combined from 1-12 species were investigated.