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.

This thesis aims to present the essential background on how to perform climate changeimpact assessments, and to present the results from a climate impact assessment on waterbalance and nitrate leaching for an arable Swedish soil. The soil is a sandy soil in southwesternSweden, grown with spring cereals. This study is meant to be a benchmark example,and cannot be seen as a regional or national assessment for Sweden, rather as an approachto present and analyze the most important parts of these kinds of assessments.A dynamical simulation model (COUP, Jansson and Karlberg, 2004) was used for thisstudy. The model was parameterized and calibrated against data from an experimental site,located in Mellby in Hallands county, south western Sweden. Measurements were carriedout between 1st of April 1988 and 1st of April 1991.

The eutrophication of inshore seas, lakes and watercourses is mainly due to leaching of nitrogen and phosphorus (P) from agriculture. Many efforts are made to reduce the lea-kage of phosphorus in Sweden and the Baltic Sea countries. Phosphorus is also a finite resource and the mining of good quality raw material gets more and more difficult. Se-dimentation dams in combination with filters is one relatively new method to separate P from run-off and drainage water from agricultural land. This study was a part of an IVL Swedish Environmental Research Institute?s project which tests the capacity and func-tion for separation of phosphorus in four phosphorus filters.

Hunger is a problem in some parts of the world (www, FAO 1, 2012). The lack of food is often a result of insufficient knowledge in soil fertility management (Röing de Nowina, 2012). Ongoing hunger and malnourishment are quite prevalent in Sub-Saharan Africa and are often combined with poverty (www, FAO 1, 2012). Farming is the most common occupation in this area and the farms are often small-scale farms with subsistence crops and a few cattle. The farmers who operate these small-scale farms are economically a weak group.

Corn is an important food and feed crop in the world, in Sweden it?s up till now grown on limited acreages mainly for silage. But I think it can get more important if you can grow it also for grain, because it?s a good animal feed for example, for life stock-, pigsand poultry. On of corns advantage is that it can produce the same amount of dry matter as for example wheat, barley and rise but with 25% less water. I will examine if it possible to grow corn for grain production in the south of Sweden.

Studien var en del i ett större projekt som syftade till att undersöka hur värphöns påverkas beteendemässigt och nutritionellt av ökad konsumtion av olöslig fiber. I det nu aktuella projektet undersöktes hur ökat intag av olöslig fiber påverkar äggkvalitén. Fiberkällan utgjordes av halmpellets som antingen blandades i fodret med 3 % inblandning, alternativt utgjorde strömaterial för att undersöka strömaterialets betydelse som fiberkälla. Två olika hybrider ingick i försöket, 720 Lohmann Selected Leghorn (LSL) och 720 Lohmann Brown (LB), varav halva antalet av varje hybrid hölls i frigående system och andra hälften i inredda burar. Totalt insamlades och undersöktes 180 ägg från varje inhysningssystem då hönorna var 31-32 veckor gamla.

In order to produce grain in an economically rational manner numerous decisions have to be made. One of these decisions is what tillage system to use. The cost of the tillage system is a large part of the total cost in grain production. Different tillage systems result in different distribution of fixed costs, operating costs and timeliness costs. The price of the produced grain and cost of inputs also affect the best way to produce grain.

Crop efficiency in utilizing available nutrients is an important factor in increasing produc-tivity and reducing the environmental impact of agriculture. Nitrogen is the nutrient that plants need in the largest quantity and wheat, along with maize and rice, is the world's most cultivated crop. In this work, the Nitrogen Use Efficiency, NUE, during the major growth period, HTP, of twelve different spring wheat varieties, were examined. The NUE was calculated as the product of uptake efficiency of nitrogen, UN, and the conversion effi-ciency of nitrogen to biomass, EN. The purpose of this work was to find if there are varietal differences in NUE and its components among the twelve varieties and to link a high NUE to specific characteristics of the varieties.

For many years, sugar beets have been the most profitable crop for farmers with suitable growing prerequisites. During year 2007 when the grain prices increased and the EU reform decreased the payment for sugarbeets, it was no longer obvious to grow sugar beets in the crop sequence. With the latest agricultural reform in mind, farming has turned to a more open market and that is important for the independent farmer to adjust to the prevailing market presumptions. In the theory, scientists distinguish between unique and repetitive decisions. Unique decisions can be described as decisions made ones or not often. The opposite, repetitive decisions are decisons that have been made several times before.

A severe profitability decline in sugar beet production in all of Europe is one of the consequences of the latest reform of the EU sugar regime. In south of Sweden, sugar beets is the crop that has been the most profitable by far for the last decade. The high profitability has contributed to the high rate of increase in the price of land and has restrained the structural change towards a more effective agriculture. Because of the reform, all sugar beet producers are facing diminishing income and must find ways to compensate this. The aim of this master thesis is to study how Swedish farmers adapt to the sugar beet reform. A questionnaire was sent to 354 randomly selected sugar beet producers.

The trend towards increasingly large farming units raises questions regarding how to better monitor production. Larger units make the impact from possible errors more severe, which increases the pressure on management supervision. To cope with management issues, prevent errors and handle increased demands on traceability and documentation, the Real Time Location Systems (RTLS) concept is making its way into various parts of agriculture. In sectors outside agriculture, RTLS are already being used successfully to track and locate items through nodes at different levels of accuracy, such as room level or the relative or absolute position. Empirical data can be received in real time from the nodes.

This study investigated potato growing in beds as an alternative to conventional ridges.It was based on results from field trials on bed-grown potatoes carried out by Halland Rural Economy and Agricultural Society in 2007, studies of literature and interviews with farmers with experience of bed growing of potatoes. Due to their shallow root system, potatoes are one of the most drought-sensitive crops. Potatoes are often grown on sandy soils with poor water-holding capacity. Factors such as total yield, tuber size distribution and quality defects are negatively affected when water becomes insufficient. Wide beds have a more flat top which leads to more uniform water infiltration. Further on, beds have lower soil surface area due to its shape, and therefore, retain water more efficient. In the field trials, which were carried out at the Stjärnarp Estate near Halmstad, potatoes were grown in beds alongside a conventional ridge-grown crop.

Naturskyddsföreningen gav författarna uppgiften att undersöka förekommande viskosprocesser och alternativa regenereringsprocesser, detta för att identifiera hur hållbara de är ur ett miljöperspektiv och vilka processer som går att applicera på bambu. Detta för att se möjligheten att märka bambuviskos med Bra Miljöval och för att klargöra frekvent uppkommande frågor angående bambuviskos. Syftet är att se på de olika processernas kemiska innehåll samt vilka utsläpp de orsakar till luft och vatten. Ett delmål med rapporten är att den ska kunna användas som material vid vidareutveckling av kriterierna för Bra Miljöval Textil. Resultat som erhållits vid jämförelser av studerad litteratur är att de betydande faktorerna för miljöpåverkan från massaframställningen samt viskos- och lyocellprocessen beror av: använda kemikalier i processen, energianvändningen och vilken typ av energi, möjligheten till rening av utsläpp till luft och vatten samt återvinning av energi och kemikalier.

The aim of this study was to increase the knowledge about whooper swan (Cygnus cygnus) ecology to enhance the ability to predict and also to prevent the crop damage they cause. The largest proportion of damage in Sweden has been reported at stopover sites during spring migration in February, March and April. Therefore, this study focused on an important stopover site, Lake Tysslingen, situated in south-central Sweden. Specifically, the relation between the duration and period migrating swans stage at the stopover site and mean temperature (measured at three different weather stations) for the years 2001-2010 was studied. Furthermore, the swans´ selection for certain fields in relation to field type, distance to roosting site, a supplemental feeding site and forest edge within agricultural land surrounding the lake was analyzed.

The price trend on rapeseed the latest years has led to an increasing interest to grow the crop among many farmers in Sweden. The price trend has resulted in more than a doubling of the oilseed area since the early 2000s. For many farmers it is an advantage to increase cultivation of rapeseed because of the high proportion of cereals in the crop rotation on many farms, but it is not just benefits. The risk of the fields being infected by clubroot increases within frequent rapeseed cultivation and it often leads to subtantial economic losses. Clubroot is caused by Plasmodiophora brassicae that is a soilborne pathogen in genus Protozoa and its resting spores can be found in the soil for up to 18 years.