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763 Uppsatser om Soil carbon - Sida 44 av 51
Uptake of 137Cs by fungi and plants due to potassiumfertilization in Heby municipality in response to theChernobyl nuclear accident
The fallout from the Chernobyl nuclear accident resulted in large deposits of caesium, iodineand strontium as well as noble gases in various parts of Sweden. 137Cs has a radioactive halflifeof about 30 years and is therefore one of few radio-fission products remaining inmeasurable quantities in the Swedish soil. Radiocaesium behaves similarly to potassium insoil-plant systems and is easily absorbed by plants. It is important to understand how 137Csbehaves in different ecosystems in order to minimize the risk toward humans.The aim of this study was to determine how potassium fertilization influences radiocaesiumcontent in different forest plants and fungi. Potassium fertilizer was spread once in 1992 withapproximately 200 kg KCl per ha.
Vattenkvalitén i Fredstorpsbäcken - dikad bäck på fastigheten Rämningstorp i Skara kommun :
The estate of Rämningstorp in the region of Västergötland in southern Sweden is administered by the holding trust company Skogssällskapet i Skövde. In 1999 measures were taken by Skogssällskapet to drain the stream Fredstorpsbäcken as a means to increase the forest productivity of the surrounding lands, which are situated on the estate of Rämningstorp. Almost immediately after the drainage, the streamwater turned turbid and a landowner downstream reported the issue to the county administrative board of the region.
The aim of this thesis was firstly to analyse the suspended matter that appeared during summer/autumn and secondly to explain why it came to be. Initial hypotheses for the explanation to the greyish turbid water were that it was either 1) a chemical/biochemical precipitate, or 2) an bacterial/algal blooming.
Solenergi på Kvarnholmen
In recent years it has become more and more evident that man has contributed to much of the climate changes that have taken place during the last century. A major challenge today is to reduce emissions and energy usage at the same time as the global population is growing. To contribute to a better environment, Stockholms Stad has set at target of becoming fossil fuel free by the year of 2050. The construction of new districts is done with this goal in mind; energy efficiency and renewable energy sources are examples of methods to achieve this.Solar energy is considered to be a sustainable energy source and the most common techniques to harvest solar energy in Sweden are solar cells and solar collectors which produce electricity and heat respectively. This report aims to investigate whether an investment in any of these systems would prove to be economically beneficial at Kvarnholmen, a district under construction in eastern Nacka, Stockholm.Since the finished blueprints only cover a small portion of Kvarnholmen, the report examines the possibilities for a house where construction has already begun, Nya Kvarnen.
Utveckling av substratmixen vid Mosseruds biogasanläggning : Substratkartläggning och rötningsförsök i laboratorieskala
The world?s growing need for energy together with a desire to ward off the worst consequences of global climate change has resulted in a never seen desire to invest resources in renewable energy sources. Biogas production through anaerobic digestion is one of those growing energy sources. In Sweden there are over two hundred plants that uses this biological process to break down organic substances while producing carbon dioxide and the energy-rich gas methane.This master?s thesis has focused on development of the mixture of different organic substances that is treated at a specific plant, namely Mosserud biogas plant.
Bedömning av området energi : En jämförelse mellan Miljöbyggnad, Svanen, FEBY12 och PHI
The Swedish building and property management sector are responsible for about 30 % of the total energy use. In order to take environmental consideration, different environmental assessment tools and standards are used. Miljo?byggnad, Svanen, FEBY12 and PHI are some of these. There has been increased interest to certify buildings and therefore it is of interest to evaluate the assessment of the energy field to see if relevant energy aspects are assessed.
Träd och buskar i kantzoner : en undersökning av kanteffekter i några av östersjöregionens skogar
Around the world, forests are generally being fragmented and as plant populations decline in both sizeand number of individuals, the genetic variation will also decrease whitch in the end leads to totalextinction of the plant. In this paper, I wanted to investigate what specific species of trees and shrubsyou usually find in the edge and core habitats in some of the forests in the Baltic Sea region. I alsowanted to identify the edge effects and their sources and finally compare the results between thedifferent regions.The data sources used are derived from the ongoining research project Landscape structures, patterns ofbiodiversity and conservation strategies in the Baltic Sea region by Kari Lehtilä, Patrik Dinnétz ochTiina Vinter who have made a record of all herbaceous plant species in four randomly chosen forestregions situated around the Baltic Sea: Estonia, Skåne, Södermanland and Germany. I made statisticalanalyses, using the computer program R, concerning the distribution of species in the edge habitats ofthe forests as well as in the core habitats. I performed generalized linear models and then variationanalyses with the factors light and biomass in order to investigate wether edge effects might appear dueto these factors.
Årstidsdynamik för kvicksilver i ett sövattensediment :
The limit for mercury in fish, set by health authorities, is exceeded in about half of the lakes in Sweden. Methyl mercury (MeHg) is the most toxic form of mercury and accumulates in fish. Therefore transformation of inorganic mercury (Hg) to methylmercury (MeHg) is an important process that we need to understand in order to possibly counteract the negative effects of mercury in the environment.
The seasonal dynamics of mercury biogeochemistry is likely of great importance for the accumulation of MeHg in the aquatic food web. In thesis the chemical speciation and transformations of Hg and MeHg in bottom waters and sediments is followed in Ängessjön, a small lake located on the east coast in the middle of Sweden. The lake is not directly affected by any industrial pollution and concentrations of Hg in the sediment reflect the atmospheric deposition in this area, as well as processes taking place along the hydrological pathways from soil to lake.
Samples from sediment, bottom- and streamwater were collected in average every second month during the period Feb.
Interactions between some plant-parasitic nematodes and Rhizoctonia solani in potato fields
The pathogenic fungus Rhizoctonia solani causes major economic losses for potato producers in Sweden. The producers, as well as advisors, have reported possible increases in severity of R. solani when free-living plant parasitic nematodes are present and active. There are several examples in the literature of interactions between pathogens where one, or both species, support or increase the damage made by the other organism. These complexes are important to investigate and to be able to forecast, since even low incidences of fungi or nematodes may result in an interaction of significance.
Design Program for Dessie Campus, Wollo University, Ethiopia
A geographical position and its social, cultural and political context as well as climate
and specific physical characteristics define the scope for a landscape design project.
This has become clearer for us in our master project where we have made a Design
Program for the outdoor environment of Wollo University in Dessie, Ethiopia and
analysed and reflected on the work and process. The aim for the project has been
to design an attractive and functional outdoor environment for the Campus, based
on the inventories and the needs and wishes of clients and users. But, the aim has
also been for us as landscape architect students to gain a greater knowledge about
landscape architecture and the design process by position ourselves outside our usual
context. The method has been open and seeking where the site, literature studies,
dialogues with people and our own experiences from the field study in Ethiopia has
influenced the work.
Wollo University is situated 400 kilometers north of Addis Ababa, in a
mountainous landscape. It faces problems of heavy rainfall during the summer,
soil erosion, a lack of essential facilities, and is still a construction site with empty
spaces in-between buildings and infrastructure.
Ökad resurseffektivitet i kraftvärmesystem genom säsongslagring av värme
Increased resource efficiency in an energy system could result in large economic and environmental benefits. Tekniska verken i Linköping AB (Tekniska verken) is responsible for the district heating network in Linköping. Their vision is to create the world?s most resource efficient region. An important step towards this vision is more efficient usage of produced heat, something which could be achieved through integration of a seasonal heat storage in the energy system.
Ödesstund för Europa : Om de geopolitiska konsekvenserna av Europas beroende av rysk energi
This is a tale about energy and power. It describes the geographer Halford Mackinder?s geopolitical theories and compares them with current views outlined by Zbigniew Brzezinski and Michael T Klare, among others. With a critical approach it also provides a historical account of a Europe that stands in front of an energy struggle so severe that the current world order seems destined to fall. Oil and natural gas, has since the beginning of the 20th century, been used as a geopolitical tool in order to create dependence, control and even sometimes overthrow empires.
Viltanpassad röjning längs skogsbilvägar som en foderskapande åtgärd för älgen
The moose is a keystone species in the boreal forest ecosystem, but the dense Swedish population do cause some serious problems. From a forestry perspective, their browsing on young Scot pine (Pinus sylvestris) causes extensive losses of revenue. Adjusting the cleaning along roadsides of low trafficked forest roads can favour the production of plant species preferred by the moose. This is thought to redirect the moose´s browsing to the roadsides and thereby decrease the damages on commercial forest.The aim of this study has been to present a first evaluation of the vegetation in roadsides, one year after wildlife-adapted roadside clearing has been undertaken. In the wildlifeadapted clearing operation, the roadside was widened by removal of some trees in the forest edge whereupon a complementary clearing with a conventional chain flail was conducted.
Kemisk stabilisering av gruvavfall från Ljusnarsbergsfältet med mesakalk och avloppsslam
Mine waste from Ljusnarsbergsfältet in Kopparberg, Sweden, is considered to constitute a great risk for human health and the surrounding environment. Some of the waste rock consists of sulphide minerals. When sulphide minerals come into contact with dissolved oxygen and precipitation, oxidation may occur resulting in acid mine drainage (AMD) and the release of heavy metals. The purpose of this study has been to characterise the waste material and try to chemically stabilize the waste rock with a mixture of sewage sludge and calcium carbonate. The drawback of using organic matter is the risk that dissolved organic matter can act as a complexing agent for heavy metals and in this way increase their mobility.
Volume and taper equations for Sitka spruce (Picea sitchensis (Bong.) Carr.), Norway spruce (Picea abies (L.) Karst.) and White spruce (Picea glauca (Moench) Voss) in Iceland
The aim of this study was to evaluate different types of volume and taper equations that can be used to predict single-tree stem volume and stem diameter at any given height along the tree stem for plantation grown Sitka spruce (Picea sitchensis (Bong.) Carr.), Norway spruce (Picea abies (L.) Karst) and White spruce (Picea glauca (Mounch) Voss) in Iceland. A number of published tree volume equations were tested and modified to predict the total stem volumes over bark but three logarithmic equations were taken for more in-depth analysis. Three taper equations were tested. Two variable-exponent equations (Kozak 1997, Kozak 2004) and one exponential equation described by Biging (1984). Data from a total of 617 sample trees were used in this study, collected from stands in various parts of the country and present different types of stands growing in different soil types and cover most of the site conditions suitable for forestry in Iceland.
In search for sustainable alternatives to lawns : connecting research and landscape design
A large part of Sweden?s green, urban landscape is covered by lawns. Approximately 80 000 ha of maintained grass lawns are part of public courtyards, schoolyards, parks, golf courses, sport fields and traffic environments. Beyond this figure, the lawn is also an essential element in most private villa-gardens. Lawns have become a universal phenomenon through the dispersion of landscape aesthetics from the Western world.