There is considerable variation between stallions in semen quality and fertility due to the fact that selection of stallions for breeding is not based on fertility or semen quality but on performance. The increasing use of cooled semen for artificial insemination has resulted in decreasing pregnancy rates. Therefore the equine breeding industry needs new methods for evaluation and development of sperm quality and fertility. This study is a part of such a project and is performed by SLU in cooperation with Flyinge AB. Ten stallions at the Flyinge National Stud were used in the study and three ejaculates were collected from each stallion.

Phosphorus is essential to all plants and is taken up from the soil as the ion H2PO4 - (and to some extent HPO42-). Plant availability depends on, among other factors, the soil pH. In order to provide for plant available phosphorus, it is applied as mineral fertilizers and farmyard manure. However, that causes phosphorus leaching from arable land to surrounding surface waters and lakes and contributes to the eutrofication. There are three types of soils in Sweden that are at higher risk of contributing to phosphorus leakage.

Pulsatilla vernalis is one of several endangered plant species that benefit from wildfires and small scale disturbance events that repel competing vegetation and create open patches in the vegetation cover. Previous studies argue that Pulsatilla vernalis is decreasing in numbers due to vegetation changes associated with the decrease in wildfires, forest grazing and changes in forest management. In this study, 17 populations of P. vernalis were inventoried in order to examine if soil and/or vegetation structures affect the population structure of P. vernalis (i.e.

A literature study and a field trial have been carried out in order to investigate the physiological response of potato plants to different soil moisture levels. Higher yield, quality and number of tubers can according to the literature be obtained if constant high soil moisture is kept during major parts of the growing season. A field trial was set up where drip irrigation was used as an alternative to conventional irrigation techniques to maintain high and constant soil moisture. The application of water in the drip irrigated area was monitored and adjusted on a daily basis so that the soil moisture stayed as close as possible to the recommended level. The sprinkle irrigated area was irrigated according to traditional practices with approximately 35 mm every 7th to 10th day depending on the whether.

Pathogenic microorganisms pose a big threat towards food production. Meanwhile, negative impacts on humans and environment are seen by the use of pesticides. Biological control agents are an alternative to the use of chemical pesticides, and plant-growth promoting rhizobacteria, such as Bacillus amyloliquefaciens has been shown to have good properties as biocontrol agents. Before these bacteria can be used commercially their impact on other soil organisms has to be evaluated. This thesis looks into what biocontrol bacteria are and how they might affect earthworms.

Millions of preselected progeny have been born since the development of The Beltsville Sperm Sexing Technology 1986. The method is based on flow cytometry and sorting is done on the basis of DNA difference of the X- and Y-chromosomes. Preselection of progeny provides an opportunity to obtain genetic gain and increased production as well as increased animal welfare and decreased environmental impact. However, the method is associated with low fertility, high costs and uncertainty whether the sorting process contributes to DNA damage and thereby results in genetically impaired progeny. Today, sex sorted sperm is only commercially available in the bovine industry, due to the fact that bull sperm is more suitable for selection than sperm from other species.

The Arctic region appears as a pristine remote environment, yet there is increasing evidence that it is greatly impacted by pollution such as lead (Pb) and mercury (Hg). In this environment deposition of Hg has increased threefold since the last industrial revolution. In this study five cryosolic soil profiles within non-sorted circles (NSC) in the Abisko region, northwest of Sweden, has been analyzed to improve our understanding regarding how pollutants are distributed within such type of soil. The soil samples have been analyzed with the use of X-ray fluorescence analysis (XRF), for the measurements of the total concentrations of e.g. lead (Pb) and zirconium (Zr).

Arvika Fastighets AB is a municipal subsidiary tasked with managing all green areas in the municipality, with a strong focus on the City Park and plant beds in the city centre. These areas generate large amounts of green waste, which is currently transported to the municipality's composting area at Lycke. Currently, the material is piled up and turned once a year without using the resulting soil for flowerbeds, lawns, and shrub/tree plantings. The purpose of the study is to determine if Arvika can compost the green waste in a more efficient manner and produce weed-free soil ready to be mixed into various substrates for different purposes. Interviews with the Swedish Church and several municipalities in Sweden have been conducted to learn from their experiences and knowledge of how they make their composting work.

One key factor in silviculture today is sustainability. In order to achieve sustainability it may be important to restore lost nutrients to the forest after clearcutting. In order to calculate the removal, you need to know how much of different elements you will find in different tree compartments. The aim of this study was to investigate if the concentration of elements in different tree compartments of spruce (Picea abies (L.) Karst) were related to the moisture conditions of the site. Five plots at Risfallet (60º 21´ N, 16º 13´ E), was placed along a moisture gradient in a 40- year spruce stand.

Soil properties affect the chemical composition of soil water. When studying transport of chemical substances through a basin, it is therefore important to know from which soil layer the main part of the runoff is generated. The aim of this study is to develop an HBV/PULSE model with merged soil moisture and response routines, which generates good approximations of groundwater levels. It should be possible to extend the model to simulate transport of substances and take into account which soil layer the groundwater level is currently in. The hydrological version of HBV/PULSE is used since there is no need to account for pH or alcalinity at this stage.

Nematodes are perhaps the most common animals in the world. Nematode populations can reach densities up to several millions per square meter in the soil. There are many factors which affect nematode communities in arable soil with respect to diversity and population size. Factors like tillage, crop, fertilization, nutrient status and moisture in the soil all have an impact on soil biology and in this way also have effects on the nematode community. This study is based on three different parts, soil samples taken in March 2012 and March 2013, soil samples taken monthly during the growth season of 2013 in bare fallow plots and a pot experiment.

During the last couple of years it has been more important to reduce the driving on the field to prepair the soil after ploughing. The machine costs are high so it is necessary to be effective. To reach a pleasant soilbed directly after ploughing is sometimes possible on easier soils but heavier clay soils always need more tillages. There is a lot of equipment mounted on the ploughs on the market, for example Furrow Cracker and Furrow presses, which makes a pleasant soilbed on easier soils. The last year Överum and Kverneland have presented knives which are mounted on the wing or moulboard.

Acidification is a central concept in the environmental debate. The effect of acidification of the soil is a matter of a decreasing amount of cations and thereby a decreasing ability to resist a supply of hydrogen ions to the soil. Acidification has gradually increased in the O horizon in Västerbotten over a 30-year period from the 1970th to the 1990th. The aim of this study was from inventories of The Swedish National Forest Soil Survey and The Swedish National Forest Inventory explain and quantify the acidification that has occurred in the O horizon of two regions in the north of Sweden. Data from SMHI, The Swedish Meteorological and Hydrological Institute, has also been used.

The thesis has been made for NCC Teknik in Gothenburg. The NCC Corporation is one of the largest leading companies in Scandinavia within the construction industry. NCC is active throughout the whole construction process, where one part is to carry out soil investigations prior the construction of various buildings, for example residential buildings. NCC Technology wants to visualize the samples taken at the construction sites in 3D for clients, authorities and also internally to show in a simple and understandable way how contamination is spread out in the soil.The thesis includes the area of Limhamns läge in Malmö, previously an industrial area. The area has previously included a concrete factory and the contamination from that factory has lingered in the soil.

Understory vegetation and fungi are regarded as important ecological drivers of processes like productivity and nutrient cycling in boreal forests. Whilst those processes are linked to soil water content, relatively little is known about the sources of soil water for these forest components. During early autumn in boreal forests, temperature falls and large events of rain are frequent which may influence soil water availability. To better understand the autumn plant-soil-fungi water relationships in this ecosystem, I used stable isotopes techniques in this study to examine the water sources for ericaceous shrubs and fungi in a Scots pine forest following a large, early autumn rain event. I hypothesize that ericaceous shrubs of two functional groups (evergreen vs.