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523 Uppsatser om Contaminated soil - Sida 17 av 35
Kvalitetssäkring av markberednings- och planteringsuppföljning hos SCA Skog AB Jämtlands skogsförvaltning :
Quality assurance means to systematically work for better understanding of the customers needs, demands and expectations. The goal for this study was to investigate how quality can be assured in the job follow up that is made by forestry contractors after soil scarification and planting. The study consisted of a description over the current follow up process at SCA forest AB Jämtlands forest administration, analysis of current follow up situation and an investigation of follow up process made by contractors in other line of business.
The first step was a statistical comparison where the own follow up made by contractors were compared with follow up made by SCA them selves over 100 stands. Two soil scarification contractors and two planting contractors carried out the silvicultural measures. The results showed that significant differences between a number of quality factors measured, for example number of approved plants or approved scarification points, average score on stand and number of totally planted plants.
Anlockning och gnag av snytbaggar (Hylobius sp.) : effekt av plantstorlek och behandling med metyljasmonat
Two field experiments were conducted in central Sweden in order to: 1) Determine a relationship between the number of approaching pine weevils (Hylobius sp.) and the number of attacks by pine weevils, in relation to the size of seedlings of Scots pine (Pinus sylvestris). 2) Determine if application of methyljasmonate (MJ) on seedlings of Scots pine will result in higher resistance towards attacks by pine weevils and/or have any effect on the number of approaching pine weevils. The field experiments were designed with two separate parts in close vicinity on the same clear cuttings: a) pitfall traps placed in patches of scarified soil that caught approaching pine weevils at 2.5 cm from the bait, which consisted of different sized seedlings of Scots pine some of which were subjected to application of MJ and b) the same type of seedlings planted out in patches of scarified soil.
The first field experiment was conducted on a 1-year old clear cutting outside Uppsala in east central Sweden and the trapping part of the experiment consisted of 8 blocks with 6 treatments: 1) control, 2) small over-wintered seedling, 3) medium sized seedling, 4) medium sized seedling treated with 0.5 ml 100 mmol MJ 4 days prior to start of experiment, 5) large seedling, 6) vial with 9.5 ml of ?-pinene. The trapping experiment lasted for 6 weeks in the early summer.
Hackerör på Sydsvenska höglandet : vad skiljer röjningsröseområden från celtic fields, stensträngsområden och bandparcellområden?
From the pre-Roman and Roman Iron Age, a number of different fossil agrarian landscapes can be found in southern Sweden - clearance cairn areas, celtic fields, stone-wall complexes and geometrically laid-out strip fields. With two different comparative analyses, this paper tries to explain some of the differences between clearance cairn systems and the other fossil field systemsThe shape of the early Iron Age agrarian landscape varies between different provinces of southern Sweden. At Gotland, celtic field systems were laid-out before 500 BC. In Småland at the same time, areas with clearance cairns were created. How can the difference be explained? The different physical appearance of clearance cairn areas and celtic fields can be explained by the different ways to handle the ard in till and in sandy soil.
Numerisk simulering av jordtryck mot rörbro ? Med tillämpning av programmet PLAXIS
This thesis deals with numerical simulation of earth pressure against tubular bridges in the software Plaxis. Plaxis is a FEM (Finite Element Method) software based on numerical calculations for which approximate solutions are developed through an iterative process. The program is specifically designed for soil and rock mechanical tests, such as voltage and deformation calculations in soil.The Royal Institute of Technology conducted in 2005, field tests on tubular bridges of corrugated steel, which was part of Ersa Bayoglu Fleners PhD (Bayoglu Flener, 2009). She studied how two different tubular bridges deformed during installation and filling. Tests and measurements were made during filling.
Ekologisk slaktgrisproduktion i Sverige :
This literature review describes organic pig production in Sweden, its advantages and disadvantages, but also how its problems can be reduced or solved. Organic pigs have the possibility to a more natural behaviour than conventional pigs. With outdoor pigs comes problems, especially during wintertime, concerning water and feed supply, thermal environment and supervision. Parasites and leakage of plant nutrients are other difficulties that comes with outdoor pigs. All problems and difficulties can be reduced or put right through correct management.
Fosforgödslingseffektivitet i långliggande bördighetsförsök
Rapid population growth and the fact that phosphorous is a limited resource implies that the question regarding an efficient use of phosphorus is of great importance, and consequently,that the phosphorous use efficiency should be as high as possible. The view on phosphorous use efficiency, and how this is calculated, has varied over time. This has had great implications on what type of research that has been conducted, which have resulted in an
inconsistency between the academic?s view on the subject and recommendations received by farmers. The purpose of this paper is to calculate the phosphorus use efficiency in the Swedish long term fertility experiments.
Avena Sativa - En hyperackumulator? : En studie av havres kadmiumupptag
The aim of our research was to investigate if oat is capable of extracting cadmium to such extent that it is usable in decontaminating polluted soils. We grew oat in a hydroponic culture during 28 days in a controlled environment and a total of 30 plants were used. The nutrient solutions were contaminated with cadmium of ten different concentrations after seven days. After harvesting the plants, the roots were separated from the shoots, placed in separate containers and then turned to ashes. The cadmium content was measured three times per sample in an atomic absorption spectrometer.Our results indicate that the ability of oat to extract cadmium from a solution is linearly dependent of the cadmium concentration of the solution.
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.
Fuktproblem i chilenska småhus
Humidity problems and poor ventilation are factors that we associate with poor indoor airquality which are known to negatively affect health. Such problems have decreased with timein Sweden but, in other countries this is still a major problem especially during winter. InChile, this is most common in the central regions of the country, especially the Strait ofMagellan. This issue is primarily due to surface condensation happening indoors which bringsabout dampness which facilitates the growth of fungus and stains, foul odors, metal corrosionand more. This is due to a combination of poor ventilation and insufficient forms of heatingalong with buildings which have no insulation.
?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.
Möjligheter att öka effektiviteten och det ekonomiska utfallet av barkhanteringen vid Seskarö sågverk :
The sludgebark and to a certain extent the bark were until a decade ago waste products without any economic value that were thrown away. A number of environmental laws and increcing energy prices have improved the prerequisites for increasing the use of these materials. At Seskarö sawmill they burn the sludgebark and a great deal of the bark in the sawmill furnace. The sludgebark has a number of disadvantages compared to bark during burning. The sludgebark is often wet which means the energy net from burning often gets low.
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.