Due to excess precipitation that cause runoff, all soils in Sweden naturally leaches nitrogen.High leaching from arable land is an environmental problem when the runoff reacheswaters. In the international agreement, Baltic Sea Action Plan, the aim is to reduce therunoff of nutrients. Sweden has agreed to reduce its load of e.g. nitrogen to the Baltic Sea.One of the proposed measures is an increased use of site-specific N-fertilization, which hasbeen shown to increase nitrogen use efficiency and therefore also reduce the nitrogen runoff.Either yields are increased with the same total amount of nitrogen, or the total quantityof nitrogen is reduced with preserved yield levels, which is profitable for the farmers.The dynamics of nitrogen leaching differs between top dressing applications above orbelow the economical optimum. There is a consensus about a difference in the dynamics,but not about its magnitude.

Forest streams and the associated riparian zones are sensitive to disturbances and changes that occur within these riparian areas. Particularly sensitive are small streams of low order, which will have large impacts down-stream. The disturbances that occur in the riparian zones are reflected quickly in the stream. Driving with forestry machines in the riparian zone will have detrimental effects to the soil and water. Driving the machines will lead to changes in the mineral soil composition, resulting in the reduction of porosity, less infiltration, compaction, and an increased bulk density.

Using the Introductory Carbon Balance Model, ICBM, five different crop rotations with rye 1. Rye-Ley-Ley-Rye-Beans-Rye 2. Rye-Rye-Rapeseed-Rapeseed 3. Rye-Ley-Ley-Rye-Potatoes-Rye 4. Rye-Rye-Potatoes-Wheat 5. Rye-Rye-Potatoes-Beans-Wheat-Rye-Potatoes-Rapeseed were tested theoretically in four different cultivation scenarios ? Straw left on the field, biogas digestate added as fertilizer. Labelled ?+straw+BD?. ? Straw left on the field, only synthetic fertilizer. Labelled ?+straw-BD?. ? Straw harvested, biogas digestate added as fertilizer.

Sitka spruce (Picea sitchensis) is a tree species that have its natural distribution along the West Coast of North America, from Alaska in the north to northern California in the south. Sitka spruce is a typical coastal tree species that can reach heights up to 85 meters and occurs in single pure as well as in mixed stands. The main purposes of this study were to describe the Sitka spruce growing characteristics and the volume production in comparison to spruce (Picea abies). The possibility to predict future volume production by using prognosis tools designed to be used on spruce were also studied. The material that has been used in this study are permanent sitka trials established by the Faculty of Forestry fixed Sitka trials and also material gathered in this study. A literature study was also carried out in order to determine the Sitka spruce growing characteristics. Sitka spruce has a high adaptation and a high volume production on a broad scale of soil types. The tree species is a pioneer species that has a fast early growth and in combination with sharp needles it is less susceptible to animal browsing than spruce. The factor that is the single most limiting factor for where the Sitka spruce can be planted is frost. This factor can be limited by using plant material with a well-suited provenance. According to the literature, the Sitka spruce has an average total volume production that is between 20-40% higher than spruce.

This thesis has been made on behalf of SCA Skog AB to assess the need of boron in Swedishforest fertilization. Boron has been added to Swedish forest fertilizers since the beginning of the1980s. This makes the fertilizers more expensive and therefore has the necessity of boron inSwedish forest fertilization been raised.The Swedish bedrock generally contains small amounts of boron. The boron in the bedrock istightly bound to the mineral tourmaline and mostly unavailable for plants. This leads to that thecontribution of boron to the soil from weathering is very low besides soils with marinesediments.

This report was written by Sofia Ericson and describes the degree thesis with the title: ?Connections between the growing site of bio fuel, the chemical composition of bio fuel ash and the deposit growth in a bio fuel fired boiler.? The purpose of this degree thesis was to avoid melted deposit growth in the bio fuel fired boiler at ENA Kraft in Enköping. Potassium and sodium are known to lower the melting point of bio fuel ashes and are therefore not wanted in the trees in higher amounts than necessary for the growth. Silicon is also known to be important for the deposit growth but it is not possible to say in general if higher or lower contents of silicon is better. The relation between silicon and other chemical substances is more important than the total amount of silicon.

The bacterium Lactobacillus reuteri, which natural habitat is in the intestine of mammals and birds, uses glycerol as a substrate for production of the antimicrobial compound reuterin. Glycerol has been shown to decrease the number of Escherichia coli in human feces and it is believed to be due to in situ production of reuterin. E. coli belongs to the large family of Enterobacteriaceae, naturally occurring in the intestine, and pathogenic strains of E. coli have been shown to be one of several bacteria causing diarrhoea in calves.

Burkina Faso as well as most sub-Saharan African countries struggle with providing food for a fast growing population. The dominating farming system is agroforestry parklands. Agroforestry parklands can broadly be defined as areas where scattered trees occur on farmlands as a result of selective clearing. The presence of trees in crop fields may in the long term have a positive effect on the production of annual crops. It is commonly discussed, but not proven, that the presence of trees leads to increased groundwater recharge due to higher infiltration capacity of the soil.

A today common soil reinforcement method is the installation of lime-cement columns. Lime-cement columns have been used since the 1970?s and have been a useful method for stabilizing soil at great depths. It is mostly used for stabilizing road and railway embankments because the method is economically viable and the columns are easy to install. The total costs for the installation of the lime-cement columns is dependent on the numbers of installed columns, what percentage of lime and cement that has been used and the pattern in which the columns has been installed.

Sitka spruce (Picea sitchensis (Bong.) Carr) is just like Norway spruce (Picea abies) a species in thegenus picea. The natural range of Sitka spruce is a narrow strip along the west coast of North America. Itis the most coastal of all picea species, and very dependent on the mild and humid climate along thepacific coast.Sitka spruce has been grown a long time in the countries around the North Sea, particularly in GreatBritain where it currently is the most important species in British forestry. Sitka spruce has not beenplanted in Swedish forests to any large extent before the storm Gudrun in 2005. Several studies indicatethat the production of wood biomass is higher for Sitka spruce compared to Norway spruce.

This thesis compares different methods for risk assessment of a creosote contaminated site in Vansbro, Dalarna. In a complementary study the importance of using representative data for calibration and validation of stationary groundwater models is discussed. The time dependency between surface water levels and groundwater levels on the site in Vansbro is evaluated by step response analysis. The results show that the groundwater levels reflect only long-term variation in the surface water levels. Hence the use of such long-term means for calibration and validation of the stationary groundwater models is the only theoretically defendable alternative.As a first step in the comparison of risk assessment methods the degree of contamination is evaluated on the basis of generic guideline values for contaminated soils, developed by the Swedish Environmental Protection Agency.

During 40 years of industrial production, from the end of the 1890?s until the end of 1930?s, coal and wood distillation products were manufactured in AB Carbo?s tar factory along the River Gimån in Grötingen, in the county of Jämtland, Sweden. In accordance with the Swedish Environmental Protection Agency?s Methods for Inventories of contaminated sites, MIFO, the site in Grötingen has been identified as a potentially contaminated site. In order to determine whether toxic substances pose a threat to human health and ecological systems in the area, there was a need to investigate the presence of contaminants, their levels and potential for migration.

Agricultural soils constitute the base in human food production and soil content of organic matter and plant nutrients together with soil microbial activity are all important parameters for high crop yield of good quality. These parameters are dependant on proper fertilization.Anaerobic digestion of organic wastes for biogas production generates a liquid residue called biogas residue (BR). It contains organic material and plant nutrients which makes ita potential fertilizer for arable cropping. However, it also contains heavy metals and toxic organic compounds and it is therefore in need of evaluation before usage.Microbial tests were performed aiming to evaluate the agronomic traits of four different BR and to find a viable procedure for evaluating slurry fertilizers. Two experiments where soil respiration and soil potential denitrification activity (PDA) was measured at fertilizer addition were performed.

Stabilization of subgrade is an internationally common technique to improve the characteristics of a soft soil. Improving the stiffness and bearing capacity of the subgrade enables the pavement to be designed with reduced depths of subbase and basecourse aggregates. This makes the stabilization technique both economically and environmentally interesting. Both natural and stabilized soils have high inherent property variability that should be considered when the characteristic value is derived. By analyzing the spatial variability in stabilized and natural subgrades it is possible get the parameters needed for reliability?based modeling of soil properties.

In Europe poplar plantations has been planted for more than one hundred years. In the first plantation was made in 1940. The interest for poplars has since then shifted over the years and has for long periods been very low but is now slowly increasing again. The main reasons why poplars are becoming more interesting are because of their great production potential. Nevertheless, the knowledge of how to mange poplars in Sweden are very low and very little research has been done concerning management of the species. The objective for this study was to; 1) investigate and document experience and results obtained in practical Swedish forestry, 2) to give a fair picture of the perceived advantages and disadvantages that the poplars has for the forestry, 3) document what the foresters that has experience and those who has no experience of poplar plantations thinks about the potential of poplars.