Sök:

Sökresultat:

494 Uppsatser om Excavated soil - Sida 17 av 33

Spridning av släckvattenpartiklar : En studie på spridning av partiklar genererade från brand

During a fire large amounts of particles and unhealthy agents occur.  Polyaromatic hydrocarbons (PAH) and toxic metals are examples among many others. These agents have a capacity to bond to particles and when the fire is extinguished, the particles can be transferred with the extinguish water into the soil and to the groundwater.Recent studies in particles have been conducted. A study by Ulrika Iverfelt (2014) reviled that the particles from a fire contained large amounts of both PAH and metals, which is consistent with earlier analyses. Her column experiments with particles in the size ? 11 microns and ?100 microns in silica sand, reviled that the larger particles was immobilized because the transportation was influenced by sieving or physiochemical particle and surface interactions.The transport of the particles in soil and groundwater is regulated by two main mechanisms: physiochemical surface interactions and straining.

Effekt av sönderdelningsgrad och planteringsdjup på uppkomsten från rhizom av Tussilago farfara :

Tussilago farfara, coltsfoot, is a troublesome perennial weed with deep lying rhizome, which can vegetatively generate new plants. The mechanical control of coltsfoot that is used today, "starvation", which consists of several cultivations of the soil, which fragmentises the rhizome. This results in production of new shoots, which leads to depletion of nutrient resources; as long the new plant is not allowed to establish. However, very little research has been done to investigate how the starving technique affects the regenerative ability of coltsfoot. The purpose of this experiment with coltsfoot was to investigate how fragmentation and burial depths affect the time of emergence, number of emerged shoots per rhizome fragment, number of shoots per node, and if the germination ability within nodes changes during the experiment.

Inventering av förorenad mark på LKAB's industriområden i Kiruna, Svappavaara och Malmberget

The county administration asked LKAB to make an inventory of possibly contaminated sites caused by their mining activity. The inventory should be performed according to the MIFO model, a method from SEPA which is used to assess a contaminated site. The first phase involves collection of information through interviews and site inspections and in phase 2 a general survey with field sampling is conducted.LKAB started the work with the first phase of the survey during 2003. During this project the information collected in Phase 1 was evaluated and 16 of the sites were chosen to proceed to MIFO Phase 2 (six sites in Kiruna, and 5 sites respectively in Svappavaara and Malmberget). The sampling of these 16 sites was performed during week 27 2004.

Inventering av förorenad mark på LKAB´s industriområden i Kiruna, Svappavaara och Malmberget :

The county administration asked LKAB to make an inventory of possibly contaminated sites caused by their mining activity. The inventory should be performed according to the MIFO model, a method from SEPA which is used to assess a contaminated site. The first phase involves collection of information through interviews and site inspections and in phase 2 a general survey with field sampling is conducted. LKAB started the work with the first phase of the survey during 2003. During this project the information collected in Phase 1 was evaluated and 16 of the sites were chosen to proceed to MIFO Phase 2 (six sites in Kiruna, and 5 sites respectively in Svappavaara and Malmberget). The sampling of these 16 sites was performed during week 27 2004.

?R KUSTN?RA ALK?RR I BOHUSL?N ETT ?BLUE CARBON? HABITAT?

In coastal wetlands carbon/organic matter can be stored for long periods of time thanks to, among other things, the presence of water which slows down the decomposition. Because of this, restauration and management of such habitats have the potential to decrease the emission of greenhouse gasses and help mitigate climate. Internationally these environments are called ?blue carbon? ecosystems. In Sweden, alder (Alnus glutinosa and Alnus incanata) covered wetlands along the coast is a nature type that potentially could function as a ?blue carbon? habitat.

137Cesium i myrsamhällen i Gävleborgs län 24 årefter Tjernobylolyckan

24 years have passed since the Chernobyl accident when radionuclides were spread over largeareas of Europe, including the Scandinavian countries. Today, measurable activities of 137Csare still observed in many Swedish ecosystems.Ants (belonging to the order Hymenoptera) are social insects which collect organic materialfrom a large area around their nests. This study focuses on the 137Cs activity in ant nests andthe cesium accumulation in these nests. The aims were (1) to estimate the 137Cs fall-out in1986, (2) estimate the radiation exposure of ants and (3) find how 137Cs is distributed in an anthill. Seven ant hills (occupied by the species Formica polyctena) were studied near the villageof Hille, situated north of the city of Gävle in central Sweden.

Undersökning av självspridning av contortatallen i norra Sverige

Over the past 40 years 600 000 ha of lodgepole pine (Pinus contorta ssp. latifolia (Engelm.) Critchf.) has been planted in Sweden (280 000 ha on SCA's forest land alone which represents about 15% of the company's total forest land area). In the early 70's SCA situated a number of experimental stands in order to investigate different aspects of the exotic tree, primarily growth rate. To be able to compare the two species plots with scots pine (Pinus sylvestris L.), this species was also planted at the same time and under the same conditions. A number of questions should always be raised when exotic species are introduced in an ecosystem. Invasiveness, the pathogen situation and purely ethical issues should be discussed.

Grundvattenpåverkan kring järnvägstunnlar i berg

Rock groundwater has always caused major problems when tunnelling. Water leaking into tunnels can cause large problems, not only on the construction itself but also on the environment. A continuous water leakage can lead to a declining water supply, and geotechnical problems can occur as subsidence in the ground. Therefore it is of great importance to predict the consequences that can appear in the surroundings due to a declining groundwater surface.The aim of the study was to investigate different methods for predicting leakage and changes in groundwater level due to tunnelling excavations in rock. This thesis was performed by comparing mathematical methods, actual groundwater changes and results from preliminary investigations.Investigations were made for three railway tunnels planned by Botniabanan AB.

Val av tidpunkt för markberedning vid naturlig föryngring under skärm av Pinus sylvestris i Svealand : Timing of scarification when using natural regeneration in seed tree stands of Pinus sylvestris in Central Sweden

This thesis is built on a field study that was carried out in two seed-tree stands near by Götbrunna in Uppland, Sweden. The aim was to examine if scarification carried out in spring time could generate a more dense seedling establishment when using natural generation, than scarification carried out in autumn. It was also investigated whether there were differences in mortality the first season between the two plot-types. Plots were established block-wise with 50 blocks (pairs) on each site. The spring scarification was made with a hoe during 22-23 of April.

Kalkning och vitaliseringsgödsling : synpunkter från organisationer och myndigheter samtprivata markägare i Kronobergs län

The background for this thesis is that at the beginnings of 1980´s the National Board of Forest started an experiment of lime dressing to reduce acidification in forest soil and in ground water. The purposes of this report are to explain organization?s, government?s and private landowners viewpoint on lime dressing and vitalization fertilization, some socio-economic aspects are presented. The general conclusions are that the majority of the interested party?s are positive to vitalization fertilization but the forests owner?s in generally need much more information about this topic..

Metodik för bestämning av åkerdikens status : fallstudie av ett dike i Munktorps socken

Agricultural drainage ditches are links between fields, lakes and oceans, having the potential to transport e.g. sediment and nutrients. When in a good condition, drainage ditches can act as sinks for e.g. phosphorus and sediments and prevent eutrophication downstream. The aim of this study was to determine the condition of one agricultural drainage ditch and to come up with suggestions for appropriate measures. The aim was also to determine which of the ditch?s properties that were possible to evaluate visually, which processes they represented as well as which properties required complementary physical analysis. This in order to contribute to the work of developing a method for determining the status/condition of agricultural drainage ditches.

Brand equity in the industrial purchase decision : a case study of the Swedish market for agricultural machinery

High brand equity is a great asset for companies that operate their business in a free and competitive market. Brand equity can arise from both product-related and non-product related attributes and may be viewed from many different perspectives. This study examines which different attributes that contribute to enhance brand equity from customers point of view at the Swedish market for agricultural machinery. The study have been developed using a comprehensive literature search in order to investigate the field regarding brand equity and brand image. The literature review results in one product specific and one non-product specific approach in order to examine factors that contribute to enhanced brand equity. This takes the form as one survey-based approach regarding the non-product related attributes which is examined by interpreting the extra value added by different attributes.

Biological control of Fusarium wilt on tomatoes : use of Bacillus subtilis and interactions with the earthworm Pontoscolex corethrurus in a Kenyan highland soil

It is important to investigate the potential of biological control measures in agricul-ture, especially where economic issues restrict the use of expensive inputs or when there are environmental concerns about toxicity of agrochemicals. The bacterium Bacillus subtilis has proved promising as a biocontrol agent (BCA) in suppressing various plant diseases and it has also been shown to promote plant growth in certain cases. During this study, the effect of B. subtilis on Fusarium wilt (caused by the fungus Fusarium oxysporum) on tomatoes, as well as its effect on the earthworm species Pontoscolex corethrurus was investigated. Furthermore, the combined ef-fect of the BCA with P.

Reaktionskrafter i dragarmarna på en traktors trepunktslyft : Teori och praktik

Tractors of today come equipped with a CAN-system. A CAN-system sends information from sensors to electronic control units who process the signals. The sensors measure several interesting parameters such as force, pressure and speed for various components of the tractor. This thesis discuss a force sensor which is placed in the pivot of the tractors three point linkage, the sensor measure the horizontal reaction force from the load that the tractor is exposed to. Signals from this sensor can be used to measure the force from any implement that the tractor is exposed to during an operation.

Kvantifiering och kartering av föroreningstransport inom ett avrinningsområde

The aim with my master thesis is to develop and test the applicability of methods to quantify and map solute advective travel times and pollutant transport at the catchment scale. Such quantification and mapping can increase the understanding of catchment-scale pollutant transport in general and contribute to the identification of the main sources of water pollution and the most efficient measures to reduce such pollution. The study area is the catchment of Oxundaån, about 20 km north of Stockholm. For detailed GIS modeling of water flow and catchment-scale contaminant transport in water, I´ve used new high-resolution elevation maps, land cover maps and soil maps combined with other available relevant data..

<- Föregående sida 17 Nästa sida ->