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939 Uppsatser om Plant nutrients - Sida 5 av 63
Allanblackia stuhlmannii ? a tree under current domestication: what are the soil requirements?
Allanblackia is a genus of trees that grows in the rainforests of West, Central and Eastern Africa. Its big fruits contain seeds very rich in oil which has been used by
local communities for cooking and making soaps. The native stands are threatened by overexploitation and the demand for the oil is much greater than the supply.
Domestication programs, aiming at introducing the trees to small holder agroforestry systems, have been started for some of the species. The main aim of this study was to investigate the soil requirements of Allanblackia
stuhlmannii in terms of chemical and physical parameters, as revealed by the soil conditions in native stands. Another aim was to see if these varied along an altitudinal transect.
"De tycka emellertid av gammal vana att det smakar gott, och tro dessutom att det är bra för hälsan" : samiskt växtutnyttjande från 1600-talet fram till ca 1950
Meat and fish was the most important food for the Sami people in northern Scandinavia until the beginning of the 20th century. It is not so well known that the Sami people also used a lot of wild plants as food and medicine although that kind of food was relatively common among them until the end of the 19th century. The purpose of this master thesis has been to describe which plants the Sami people used in general and also which plants were the most commonly used, and when and how these plants were harvested. I also wanted to measure the quantities of Angelica archangelica and Rumex acestosa within traditional harvest sites. Furthermore I wanted to find out if the plant use differed among Sami groups geographically.
Ersättning av Ringhals 3 med ett biobränslekraftverk
This study deals with the technical and economic feasibility of replacing the nuclear power plant reactor Ringhals 3 with a biofuel power plant. A technical investigation has been executed to determine which of the systems and components that could be reused and which ones would need to be replaced. The investment costs of the reconstruction have also been estimated. The cost of the electricity production has been calculated as well as the emissions of the new biofuel power plant. Based on the established rate of return, the lowest average spot price of electricity that makes the investment profitable has been calculated.
Plantinventering och plantkontroll med digitala bilder från helikopter :
This study was carried out as a commission from Holmen Skog, district ?Egen skog? in Norrköping. During October 2006 several stands were inventoried by aerial photos from helicopter. The stands were those for which the next action proposed was plant inventory or plant check. The photos were interpreted and the number of stems was calculated.
Simulering av vindkraftverk och närliggande elnät vid Risholmen i Göteborg i SimPowerSystems
With background in the rapidly growing need to find solutions for sustainable energy production and the increasing interest for wind power, this report was written. With take-off point from the wind power plant Big Glenn, which has been built in the harbour of Gothenburg, a model of the adjacent power grid has been created in Simulink/SimPowerSystems. Parameters for the power grid and its components has been provided by Göteborg Energi Nät, that has also been the supplier of measurement data of produced power, the power need from loads in the vicinity, voltage levels, current values and also the variation of power factor at the wind power plant.The SimPowerSystems model has been used to perform simulations of power flow in the grid. These simulated values have then been compared to the measured values to verify the functionality of the model. Further, the model has been used to perform simulations of a grid fault, which causes a voltage drop.
Turbinkretspump system - Kraftvärmeverket i Borås
The Rya power plant in Borås produces district heating, district cooling and electricity. The plant is owned by Borås Energi och Miljö AB and is run by Dalkia Facility Management AB.In order to get the best heat exchange from the district hot water a pair of twin pumps and a turbine circuit pump are used as return pumps. Turbine circuit pumps are used to increase the pressure through the heat exchangers at the power plant. The pumps are in use when the flow is over 2 000 m3 h-1 and during the summer when re-cooling is used to improve the effectivens of the heat boilers.Since the pumps, that are parallel connected, rotating at a fixed rate per minute, the pressure is regulated with regulating valves. This report shows that during the 4,300 hours that the pumps where in use, energy corresponding to 590 MWh was wasted.
VSM och 16 förluster
With background in the rapidly growing need to find solutions for sustainable energy production and the increasing interest for wind power, this report was written. With take-off point from the wind power plant Big Glenn, which has been built in the harbour of Gothenburg, a model of the adjacent power grid has been created in Simulink/SimPowerSystems. Parameters for the power grid and its components has been provided by Göteborg Energi Nät, that has also been the supplier of measurement data of produced power, the power need from loads in the vicinity, voltage levels, current values and also the variation of power factor at the wind power plant.The SimPowerSystems model has been used to perform simulations of power flow in the grid. These simulated values have then been compared to the measured values to verify the functionality of the model. Further, the model has been used to perform simulations of a grid fault, which causes a voltage drop.
Ekosystemstödjande och multifunktionella växtval i urban miljö : En fallstudie med utgångspunkt i Nacka stadsbildning
This study has investigated how urban vegetation can be used in a multifunctional way to support ecosystem services in urban environments. Nacka municipality is in the start-up phase of building what is to become Nacka city. This provides a unique possibility to study and analyse what role the vegetation play in making the city a healthy living environment and how it needs to be adapted in order to be resilient against changing climate conditions and how the effects of those changes can be regulated. The study further investigates how airborne pollution, caused by urbanization processes, can be regulated or reduced by vegetation or species selection. Methods used in this study were a combination of qualitative interviews and literature studies, seeking to answer the questions: Which specific ecosystem functions are needed in the urban environment and which aspects will influence the ecosystems ability to deliver the functions in demand? And which plant species have the right mechanisms needed to deliver those functions? These questions have been studied and analysed in a local based context where the local conditions ands site specific needs of Nacka define criteria for plant selection.
Optimering av den kemiska reningen vid Fläskebo deponi
Landfill leachate contains a variety of contaminants and is created when rainwater percolates the landfill. For landfill management the leachate is the main issue that can cause problems to the environment. At the landfill of Fläskebo, Renova AB treats the leachate in a local treatment plant. The treatment consists of a chemical treatment step with chemical precipitation, flocculation, sedimentation and filtration, and a final step with a carbon and peat filter. Renova has to ensure that the condition of the leachate reaches the regulation set for the landfill before it is released to the recipient.
Energikrav i upphandling av bygg- och anläggningsprojekt
The building and plant sectors represent a large part of Sweden?s energy use. Putting energy requirements in public procurement as a tool for reducing energy consumption in the building and plant sectors is therefor an opportunity that operators can take advantage of. The aim of this thesis was to map the energy requirements in procurement that operators in the public sector use today in building and plant projects. The analysis was made with respect to if the energy requirements corresponded to the parts with large energy use in building and plant projects and also in which way energy requirements in procurement are written in the contract.
Utredning av potentiella hälsorisker i samband med slagg- och slaggvattenhantering vid Hedenverket, Karlstad
In this study potential health risks for employees in connection with handling of bottom ash and bottom ash water at a Municipal Waste Incineration (MWI) plant have been investigated. Air surrounding the bottom ash and the bottom ash water has been examined. MWI is one of the primary ways to manage solid household waste, and bottom ash is the main solid residue produced by the incineration process. Bottom ash constitutes about 15-20% of the original waste. The bottom ash is extinguished in a water bath (bottom ash water).The study was carried out in a MWI plant in Karlstad, Sweden.
Is goat milk a better milk replacement to piglets, rat pups and foals than cow milk is?
AbstractOne opinion among people who are experienced in hand rearing newborn mammals is that goat milk is more suitable than cow milk if the young needs a milk replacer. The purpose of this literature review was to find out if there is scientific evidence that goat milk is a better milk replacer for piglets, rat pups and foals than cow milk. The milk is essential for the newborn animal, as its only source of nutrition until it has learned how to eat solid food. In this literature review, the composition of goat milk and cow milk is compared with the nutrient requirements after birth in piglets, rat pups and foals. The nutrient requirements and the milk composition are partly determined by the newborn mammals activity level and suckling frequency, which also is described.
Övergödning i Laholmsbukten En studie av Laholmsbuktens övergödningssituation
This essay discusses the Laholm?s bay and its eutrofication problems. The question of issue is: Have the efforts to limit the eutrofication in the Laholm?s bay been effective? What is the local actor?s opinion whether the measures have been effective or not? What efforts have been made to prevent the leakage of nutrients from fields and forestland? The Laholm's bay is located in the south part of the Swedish west coast. The problem was noticed in the 1960´s by local fishermen that experienced a lack of catch.
Dynamisk modellering av kärnreaktor
The purpose of this thesis has been to develop a tool for modelling and simulating the nuclear plant Ringhals 3. The model should be used to improve the knowledge on the dynamics of the plant. Ringhals 3 is being upgraded to produce more power and a tool for analyzing the new operating conditions is needed.The work in this thesis has consisted of improving and developing an existing model of Ringhals 3 made with the modelling tool Dymola. The model has been validated by comparing the results of a simulated house load transient with data from the actual plant. Validation shows good agreement with data from the real plant.
Lantbruket som energiproducent : tekniska, ekonomiska och miljömässiga förutsättningar för fjärrvärmeproduktion med lokalt skogsbränsle
A third party access to district heating networks has been proposed in Sweden, to increase the competition
on the district heating market. Such third party access could create opportunities for the agricultural sector
as an energy producer. This study describes the technical, economical and environmental prerequisites for a farmer cluster to build and run a heating plant, fueled with local wood fuel.
The heating plant in the described scenario is 8 MW and will supply a village of 1000 houses, and is fueled with wood chips exclusively. Supplying a heating plant with fuel puts high demands on the logistics, since there need to be a continuous flow of fuel. In the scenario, wood residues from felling and thinning is stored in stacks in the forest, and a few times a year chipped and transported to a storage area at the heating plant.
In the study, an estimation of the profitability has been made by estimating the cost of the investment,
personnel, operating and maintenance costs and costs for the fuel and ash handling.