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763 Uppsatser om Soil carbon - Sida 24 av 51

Handel med utsläppsrätter - hur företagsstrategier påverkas :

Climate change is one of the most difficult problems that humans have to deal with. Today, the evidence of human effects on the climate change and the rise of temperature on earth are strong. It is extremely important that all countries get together and cooperate in order to be able to solve the problem with climate change. One step in the work on climate changes is the Convention on Climate Change, which was agreed on in 1992. The Convention on Climate Change resulted in the Kyoto Protocol in 1997. The Kyoto Protocol is an agreement between a number of industrialized countries to limit or reduce the green gas emissions.

Leaf area index in Vittelaria Paradoxa parklands in Burkina Faso estimated by light interception and leaf sampling

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.

Klimatkompensering - En bra strategi för miljömedvetna företag eller ett enkelt sätt att köpa sig ett rent samvete?

På senare år har en ny trend inom miljöarbetet uppstått. Istället för att bara vara miljövänliga tar vissa företag och organisationer det hela ett steg längre och klimatkompenserar för de utsläpp de har. Företag som klimatkompenserar hävdar att de gör allt de kan för att först och främst minska de direkta utsläpp som de förorsakar. Som en sista åtgärd, för att ytterligare minska företagets påverkan på miljön, kompenserar företagen för sina utsläpp genom att delta i något miljöfrämjande projekt. De bakomliggande motiven till att klimatkompensera är främst ett starkt miljöengagemang inom företaget sedan tidigare.

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.

Optimering av biologisk fosfor och kvävereduktion i ett reningsverk för hushållsspillvatten

In connection with Henriksdals wastewater treatment plant (WWTP) a smaller plant is situated called Sjöstadsverket where new methods for wastewater treatment are tested and evaluated in different process lines. On one of the lines experiments with enhanced biological phosphorous removal (EBPR), have been carried out to evaluate if it is a good alternative to traditional chemical phosphorus removal. This thesis evaluates the results from the experiments conducted during fall 2005.The incoming water from Hammarby Sjöstad consists of only household wastewater, which gives a wastewater with high concentrations of nutrients and organic carbon. This is partly positive, because one of the limiting factors for effective biological phosphorus removal is the lack of easily biodegradable organic carbon. The high concentrations of ammonium and phosphorus demand a high reduction to achieve the requirements of outgoing concentration.To optimize the process experiments with different recirculations and different aeration techniques have been made.

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.

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.

Transporter på väg - En studie över Sveriges lastbilscentralers metoder för att möta ökande drivmedelspriser

Background and problem: In the last few years the threat against the environment and especially the emissions of carbon dioxide has become increasingly debated. The government have set up a goal to lower the emissions of carbon dioxide with 40 percent until 2020 compared to the level in 1990. The emissions in the transportation sector have, in contrast to the total emissions, increased since 1990 and will continue to increase unless powerful control measures are implemented. The lorry centres have to use strategies to answer to these external threats which lead us to the two questions of this thesis: - What methods do the lorry centres use actively and which do they consider as the most important methods for fuel saving? - Are there any differences which methods small, medium and large centres considers as important? Purpose: The main purpose of this thesis is to examine which methods lorry centres use actively and which they consider as important for fuel saving.

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.

Konvertering från direktverkande el i kommersiella lokaler : Ekonomisk och hållbar utveckling

Buildings worldwide account for 40 % of the total energy use. Climate change is of increasing importance, but few are willing to reduce their standard of living or get a higher cost for the change. Energy efficiency of existing buildings gives the greatest benefit economically and environmentally. The real estate company Klövern AB manages 46 properties in Karlstad. Heating is the major cost of the total operating costs of real estate. Rising energy prices increase the need for Klövern AB to improve energy efficiency and to investigate alternative sources of heat.

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.

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