Sökresultat:
127 Uppsatser om Dehydration of soils - Sida 5 av 9
Siktning som saneringsmetod för metallförorenad mark
Toxic metals contaminate soil worldwide and thus serve as sever environmental threat. Therefore the purposes of this study were to investigate in which soil fractions that different heavy metals (Fe, As, Cu, Zn and Pb) could be found in contaminated soils and if it is possible to use sieving as a method for decontamination. Soil samples were collected from three different locations, the Nasa silver mine, the Blaiken-mine and Svalget environmental station. The samples were oven dried and later on sieved into six different fractions 8mm, 4 mm, 0.5 mm, 0.250mm, 0.063 mm and <0.063 mm. The fractions 4 mm, 0.5 mm and <0.063 mm from each location were analyzed in an x-ray fluorescence detector.
Magasin för lagring av vatten och växtnäring
Structural rationalizations and regionalization of the agricultural sector in Sweden has lead to unevenness in thedistribution of plant nutrients. Nutrients are lost from crop producing farms as harvest products are sold, whilefarms with animal production often have manure in excess of their needs. In addition to this the retention ofwater and nutrients in naturally occurring wetlands has decreased due to a reduction of wetlands in number andsize in the agricultural landscape. This increases nutrient levels in agricultural run-off and causes eutrophicationas well as nutrient losses from arable soils. One potential solution to both problems would be to store nutrientrichsurface water from agricultural areas and use it for irrigation of agricultural crops.
Hundens parvovirus : patologi och riskfaktorer
Canine parvovirus is associated with two disorders: enteritis, which is common, and myocarditis, which is rare. Prominent clinical signs of parvovirus enteritis are vomiting, diarrhea and rapid dehydration. Canine parvovirus type 2 (CPV-2) is very contagious. When CPV-2 first emerged it had high rates of mortality, but later studies have shown that most infections are self-limiting and do not require veterinary care. Mortality rates vary greatly, and therefore it is important to determine risk factors for developing severe canine parvovirus enteritis.
Exosomes as a potential mechanism of intercellular spread of prion protein
Structural rationalizations and regionalization of the agricultural sector in Sweden has lead to unevenness in thedistribution of plant nutrients. Nutrients are lost from crop producing farms as harvest products are sold, whilefarms with animal production often have manure in excess of their needs. In addition to this the retention ofwater and nutrients in naturally occurring wetlands has decreased due to a reduction of wetlands in number andsize in the agricultural landscape. This increases nutrient levels in agricultural run-off and causes eutrophicationas well as nutrient losses from arable soils. One potential solution to both problems would be to store nutrientrichsurface water from agricultural areas and use it for irrigation of agricultural crops.
Metodundersökning av tre metoder för kvävemätning i en arktisk äng : Jämförelse mellan mätmetoderna extraktion, inkubation och jonbytesmembran (PRS-sond)
The purpose with this report was to compare three commonly occurring methods for measuring plant available nitrogen in soils. The methods extraction, incubation and Plant root simulator (PRS) probe - an ion exchange membrane (Western Ag Innovations, Inc., Saskatoon, Canada) method were used and comparison between these methods were conducted. A full factorial experiment were set up in northern Finland with the treatments excluding herbivores, warming and fertilization to see how the inorganic nitrogen content in the soil was effected by the treatments. Soil cores were taken and from them a subsample was incubated for 18 days and thereafter analyzed for inorganic N in laboratory. PRS- probes were in the ground for 1 month.
Hassel (Corylus avellana) som indikator på markanvändningshistorik
Hazel (Corylus avellana L.) is a common feature of meadows and pastures where it can grow in large populations and become very old. Is it possible to use the size of hazel stools for age determination and is it possible to use the size distribution of a population to provide information about how the land has been used? Hazel populations on ground where the lake-water level had been lowered, has been studied to validate an already developed growth model of hazel clones. Different hazel populations, on wooded meadows affected by mowing or grazing or overgrown meadows, were studied to evaluate the method utilizing hazel as land use indicator. The growth model was used to compare the size distributions of hazel populations with historical periods, which has been important for changes in agriculture or demography.
Modellering av oorganiskt kol i boreal jord och vattendrag med hjälp av PHREEQC : Modelling of dissolved inorganic carbon in boreal soils and streams using PHREEQC
Syftet med examensarbetet har varit att studera kol i mindre vattendrag med hjälp av jämviktsmodellering i PHREEQC. Fokus har varit dynamik av löst icke organiskt kol (DIC) samt att förstå hur mycket koldioxid (CO2) som avges från mindre vattendrag och om den mängden har signifikant inverkan på den globala kolbalansen. Med hjälp av provtagen data från Krycklans avrinningsområde år 2003-2007 och 2009 har modellering av DIC och pCO2 utförts med målet att se förändring både över säsong och nedströms i ytvattensystemet. För att utvärdera modellen har tillhandahållen data över uppmätt pCO2 använts. Målet var att jämföra modellerade och tillhandahållna pCO2-värden för att se hur väl modellen kunde beskriva verkligheten och om den fungerade bättre för någon plats eller under vissa delar av året.
Marktillstånd och borbrist på åkermark planterad med gran i Västerbottens län :
This study was made on former agricultural areas that had been planted with spruce or pine, in the county of Västerbotten. The goal of the project was to investigate suspected deficiency of boron in these areas. Several objects have been reported for possible deficiency and some of these have the characteristic symptoms of boron-deficiency. The hypotheses are that
1) Boron deficiency is present at several of the investigated objects.
2) Planting of forest on cultivated postglacial sediments leads to a successive podzolisation with a decreasing content of organic matter in the mineral soil, due to decomposition, and a decreasing pH in the soil, even on locations that have been added lime.
To be able to confirm or reject the hypotheses a number of tests were performed.
Rhododendron och dess skadegörare
Swedish energy policy aims to increase the use of energy from renewable sources and this should be done in a safe, environmentally and sustainable manner. According to the Energy Agency the use bio-fuel increased by 73% between 1990 - 2006. Stands with high share of slash are often located on areas with high productivity which often are located on soils with poor bearing capacity. This will increase traffic on susceptible soil leading to increased ground damage. To reduce the risk of ground damage at slash-forwarding, ground protection is needed.
Reducering av markskador vid GROT-skotning
Swedish energy policy aims to increase the use of energy from renewable sources and this should be done in a safe, environmentally and sustainable manner. According to the Energy Agency the use bio-fuel increased by 73% between 1990 - 2006. Stands with high share of slash are often located on areas with high productivity which often are located on soils with poor bearing capacity. This will increase traffic on susceptible soil leading to increased ground damage. To reduce the risk of ground damage at slash-forwarding, ground protection is needed.
Finns det potential att införa en massdatabas för handel och utbyte av överskottsmassor i Eskilstuna?
In Eskilstuna and Sweden in general the level of reuse of surplus material containing soils and rocks from excavation is low. In this report the potential for increasing the reuse of excavated material in Eskilstuna by using a web-based earth information database has been examined. The purpose of a web-based earth information database is to connect those who have surplus material with those who need material for a fast and simple transaction. The intention is to give Eskilstuna a more environmentally and economically efficient handling of surplus material by increasing the level of reuse and thereby reducing the amount of surplus material that is wasted and emissions given off to the atmosphere during transportation. The potential has been examined in two different ways, by tracing information about a number of projects to see if excavated material driven to the dump could have been used in another project and by interviewing eight of the work leaders active in Eskilstuna.
Tillsats av biokol till en svensk sandjord : effekter på lustgasavgång, kväveretention och andel vattenfyllda porer
In a column experiment the effect of three different biochars on nitrous gas emissions, nitrogenretention and water filled pore space (WFPS) were studied in a Swedish sandy soil, classified as aCryopsamment. Ammonium retention was positively correlated, while KCl-extractable ammoniumwas negatively correlated, with the specific area of the biochars. The question was raised whether thenegative correlation between extractable ammonium and biochar specific area reflects the amount ofammonium present in the soil or its extractability from the biochar, and whether methods forextracting soil mineral nitrogen, like KCl-extractions, have to be modified for application on biocharamended soils. There was a tendency of increased nitrate retention and KCl-extractable nitrate withbiochar and KCl-extractable nitrate was positively correlated with the specific area of the biochar. pHwas higher for all biochars compared with control, although the differences were not significant, andWFPS was lowered by biochar addition, significantly in one case.
Sticklingsetablering av Sedum spp. för gröna tak : biokol som organiskt material i substrat
The popularity of vegetated, or green roofs, has grown over the past years due to their potential
function of maintaining urban environment quality. The aim of this study was to investigate if
substrates with different organic material, peat and charcoal, with two contents (3 or 6 weight%)
influenced the growth of the cuttings during the first critical period of the establishment. Biochar is
used as amendment to agricultural soils and has, theoretically, many of the properties suitable as
organic content in green roof-substrates. Peat is one of the materials that is commercially used in
green roof industry. The substrate has been treated with different amounts of water.
Alternativa stråbränslen i växtföljden :
The purpose of this report is to find out which crops, that are good for strawfuel, and can be grown i the area around the city of Lund. The background of this report it that Lunds energy is planning to bild a biofuelheated thermal power station in Örtofta outside of Lund.
I have in the report limited me to the crops hemp, whole crop (triticale), reed canary
grass, elephant grass and jerusalem artichoke. I have through a documentary research
checked the crops, cultivabillity in the south of Sweden, and how they should fit, in the
Scanian crop sequence.
Hemp is an annual crop which probably could manage in the Scanian crop sequence.
Whole crop often triticale because of it´s high yield and low rate of shed seed. Could
also fit into the crop sequence of crop in Scanian. Triticale is annual, and could be
grown at the same kind of fields as used to wheat, whith is why it would be possible to
grow it in Scania.
Reed canary grass is a reedlike grass that is easy grown at most soils.
Variationer av klor, svavel och aska i havrekärna : odlingsfaktorernas inverkan på havrens bränsleegenskaper
The increasing oil prices during the last years have made it profitable to use cereal grains as a fuel. When compared with wood, cereals contain higher amounts of Cl, S and ash. The Cl and S content makes the gases from cereal combustion more corrosive than gases from wood combustion. The goal of this master thesis was to find out the variation of Cl, S and ash content for oat grain grown under different conditions. Oats was chosen because in Sweden it's considered as the cereal with the best fuel qualities.