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939 Uppsatser om Plant nutrients - Sida 25 av 63
Majs till mogen skörd :
Corn is an important food and feed crop in the world, in Sweden it?s up till now grown
on limited acreages mainly for silage. But I think it can get more important if you can
grow it also for grain, because it?s a good animal feed for example, for life stock-, pigsand
poultry. On of corns advantage is that it can produce the same amount of dry matter
as for example wheat, barley and rise but with 25% less water.
I will examine if it possible to grow corn for grain production in the south of Sweden.
Hållbar design för gravplatser
A well-planned grave with a sustainable selection of plants facilitates easy maintenance for both staff and the holder of the right of burial. It also helps reduce the negative impact on the environment.As in many other areas, the environment is high on the agenda within the cemetery administration. One of the major concerns is the impact of the choice of plants for the grave. Within the industry there is a great motivation and willingness to adapt to a sustainable work mode and this has spawned a number of project works. In autumn 2009 the partnership project, ?Environmental aspects of planning and maintaining graves?, was started in Movium (at The Swedish University of Agricultural Sciences).
Do 25 years old skid tracks restrict growth and survival? : a study on growth conditions for the planted regeneration in a rainforest rehabilitation project
The rainforests of the world are important not only to the countries in which they grow but to the world as a whole. They influence oxygen and water circulation as well as carbon sequestration which in turn affect global radiation and global warming. The forest also have great value and in Malaysia as in many other tropical countries large volumes are harvested which leaves great areas of degraded forest with little growth and biological diversity. Due to their low financial value these forests are often transformed and used for other purposes than forestry such as oil palm plantations.
The trees are often transported out of the forest using large bulldozers. They are heavy which causes compaction of the forest floor and during transport the top soil layers are moved to improve mobility.
Effekten av suggans näringsstatus på fostertillväxt och smågrisöverlevnad
The pig industry suffers economical loss due to stillbirths, piglet mortality and low birth weight. This is due to breeding programs that have resulted in larger litters. It has been suggested that these problems are due to the metabolic state of the sow during gestation and the fact that she might not be able to supply her foetuses with enough nutrients for survival and a high and even birth weight. A lot of research has been done to investigate whether body weight and back fat thickness of the sow has any impact on her reproductive traits and if there are any special feed components that improve reproduction. Fibers and unsaturated fatty acids have a positive impact on reproductive traits as long as the sow is fed a sufficient amount of energy and protein during gestation and lactation.
Utvärdering av substrat för biogasproduktion
The purpose of this study was to evaluate the different substrates that enter the digestion on Sundet wastewater treatment plant for production of biogas.This work have done an analysis of data about the biogasproduction from January 2012 to feburari 2013, this showed that the food substrates has a greater gas production than internal sludge.Through laboratory test the VS, TS and COD values for all the substrates used in the biogas production could be determinded. But the COD-method was less optimal for analysis of fat and food, therefore it optimized the method for fat but due to time constraints, this could not be done on the food substrates..
Phosphorus in agricultural soils around the Baltic Sea : comparisons of different laboratory methods as indices for phosphorus leaching to waters
Eutrophication of the Baltic Sea is a serious problem. A major contributing factor is diffuse losses of phosphorus (P) from agricultural land in surrounding countries. In order to estimate P losses, environmental monitoring of small agriculture-dominated catchments is being carried out in most of these countries. Evaluation of the risk of P leaching to waters is usually based on chemical tests originally developed to quantify the amount of soil P available for plant production. The tests are performed in different ways in the different countries and a number of different extraction agents are in use.
Jämförelse av verklig och modellerad elproduktion från en solcellsanläggning : En utvärdering av två simuleringsverktyg.
This thesis has been carried out in New Zealand in collaboration with the University of Waikato. In association with Dr. Mike Duke the purpose of this work is to investigate whether two different software for modeling of photovoltaic systems are useful in the teaching of solar energy.The next ten years grid-connected photovoltaic systems are assumed to increase and therefore also a rising demand for people with engineering knowledge are to be predicted. For engineer students with a focus on solar energy a more practical teaching with design software´s can be a good method to make the students comprehend more when it comes to large scale photovoltaic systems and be more prepared for working life.The software´s used is called Transient System Simulation (TRNSYS) and Photovoltaic Systems (PVSYST) which are both well used throughout the world. To assess the reliability of the software´s, a reference solar power plant at 16.1 kWp installed capacity are used, which consists of photovoltaic modules from four different manufacturers.
Simulering av kabelbränder i sekundära säkerhetssystem med CFD-koden SMAFS
This report contains CFD-simulations of cable tray fires in nuclear power plant applications with the CFD-code SMAFS. Furthermore the report evaluates the use of CFD-codes within this kind of problems. The assessment of this report is that there is a tendency towards the good use of CFD-codes but before using it solely more research has to be done on the subject..
3D Anpassning
This report summarize a simple and efficient way to convert 2D into 3D designs. It explains the benefits of a 3D design compared with 2D, and how those benefits may be used.It will also give the reader a presentation of the company Clean Air Technologies, which for the most part constructs cleaning facilities for power plants. How to create 3D-libraries for some of those facilities will be introduced in this composition.The collaboration with Clean Air Technologies has resulted in several 3D animated movies and rendered images. This has increased the quality of the companies offer presentations, which has made it easier for the prospective customer to get an improved overall image of the power plant design..
Honung och biodling : honungens ursprung, egenskaper och effekter på människans hälsa
This report describes honey, its origin, properties and effects on human health. Honey has been used for a long time in most civilizations and apiculture is an important activity sector in many parts of the world. The trend is an increase in honey production but a decrease in the number of beekeepers in Sweden. Honeybees live in a highly developed society with a strong hierarchy and a well organized distribution of the tasks. They visit a broad spectrum of plants and collect nectar to store it as honey.
Fånggrödor i Norra Östersjöns vattendistrikt
70 % of the lakes and waters in the water district of northern Baltic Sea do not reach the
requirements for good ecological status. This is mostly due to eutrophication caused by a too
high deliverance of nutrients from agricultural land or effluents. Losses of particulate
phosphorus through water erosion contribute to a great extent to this eutrophication. In the
action plan for the water district cover crops are mentioned as a measure for reducing losses
of phosphorus from arable land. This paper reviews the possible effect of cover crops in the
water district and discusses what crop that would be most suitable.
Svampar associerade med raps : betydelse för uppkomst och grödetablering
Oilseed rape is an important crop in Sweden and is grown on about 90000 ha today. The interest in oil seed pro-duction is increasing because of growing demand and high prices for oil seed both in Sweden and Europe. However, an increased intensity in the oil seed production can bring higher risk of yield losses due to fungal diseases. The purpose of this study was to investigate what different fungi are associated with oilseed rape under field conditions and if their incidence is correlated to crop establishment problems.
This study was carried out in three parts: 1) investigations on fungal community structure in roots and rhizosphere soils from young spring- and winter rape plants sampled in failed respectively good establishment patches in four fields, 2) investigations on the pathogenicity of fungi isolated from oilseed rape in controlled environment and 3) investigations on the effect of different fungicide seed treatments on germination and early plant development in a field soil naturally infested with damping off- and Verticillium wilt pathogens.
The studies on community structure using a combined approach of standard fungal isolation techniques and DNA based methods revealed a high fungal diversity in three out of four studied fields of spring rape and winter rape. For some unknown reason, very few fungal species were identified from the fourth field.
Biologisk behandling av oljeförorenad jord : Abiotiska faktorers inverkan och effekter av olika uppläggningssätt på nedbrytningshastigheten.
The purpose of this report was to investigate how the abiotic factors (temperature, pH, nutrients, oxygen levels and water content) would affect the decomposition of oil-contaminated soil and how a variance in structured soil would affect the decomposition-rate. A minor field-study was made and soil where structured in five different ways (one was a default pile and was used as a reference). The study took place over 137 days and three samples were taken (start, middle, end) and analyzed for aromatic and aliphatic compounds. The result of this study shows that there is a significant difference between all methods for the aliphatic compounds and no significant difference for the aromatic compounds. The abiotic factors that affect decomposition vary from organism to organism, depending on what type of environment it will function the best.
Avskiljning av uran från dricksvatten med reaktiva filter :
Water is our most important provision and its quality is above all dependent on the
geological conditions in the area from where it is extracted. Due to geological
properties there are certain areas with an elevated risk of high uranium levels in the
ground water, which in turn constitutes a risk for human health. Consumption of water
that contains a high concentration of uranium implies a health risk due to the chemical
characteristics of uranium. Livsmedelsverket (The National Food Administration) and
Socialstyrelsen (The National Board of Health and Welfare) therefore recommend that
precautionary measures should be taken when the uranium concentration in ground
water exceeds 15 micrograms per litre. In particular, drinking water collected from
wells in areas with uranium-rich bedrock may have a harmfully high level of uranium.
One of the wells of the Ärla water purification plant, located near Eskilstuna, Sweden,
contains water that exceeds the guideline of 15 micrograms per litre.
One interesting technique for removing uranium from drinking water is adsorption to
reactive filter materials.
FEM-analyser av rörstödskonstruktioner
Målet med detta examensarbete, utfört på uppdrag av Vectura Consulting AB, har varit att undersöka möjligheten att ansluta en vindkraftpark till järnvägens kontaktledningsnät. Möjligheten att koppla om vindkraftparken till järnvägens hjälpkraftnät, som bland annat förser växelvärmare och signalsystem med effekt, har också undersökts. Eftersom kontaktledningsnätet och hjälpkraftnätet arbetar med olika frekvenser och spänningar, 16? Hz och 15 kV respektive 50 Hz och 22 kV, måste därför en komplett krets för frekvensomvandling, spänningsomvandling och omkoppling tas fram. Projektet har begränsats till en del av Botniabanan, sträckan Örnsköldsvik-Nordmaling.I denna rapport har trafikfrekvensen på den valda sträckan på Botniabanan undersökts för att bestämma en genererad effekt till inkopplingspunkten, samt för att undersöka när det kan vara lämpligt att koppla om till hjälpkraftnätet.