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94 Uppsatser om Atmospheric deposition - Sida 3 av 7

Dominansaggression hos hundar

Sjöfartsektorn är en betydande källa för svavel- och kväveutsläpp. Depositioner av oxiderat svavel, dvs. sulfat, och oxiderat kväve dvs. nitrat, i form av våt och torrdeposition bidrar till försurning och försämrad luftkvalitet. Styrmedel för att minska svavelutsläppen har under de senaste åren bidragit till minskade svavelutsläpp.

Uppfångning och kvarhållning av 134Cs och 85Sr i olika växtutvecklingsstadier

Emissions of radionuclides to the atmosphere can lead to wet deposition on plants in theevent of rainfall. An increased level of radioactivity in the plants may occur due tointerception and retention of the radionuclides. If the content of the plants is above thethreshold limit value, entire yields may have to be destroyed. In order to preventcontamination or decrease the content countermeasures can be taken. The impact of thebiomass, leaf area index (LAI) and growth stage of the plant on the interception andretention is important to know in order to decide which countermeasures to use.Weather may also be an important factor.In this work the interception and retention of 134Cs and 85Sr by spring wheat, ley andspring oil-seed rape was studied.

Sustainable phosphorus management of horse paddocks at Julmyra

Horse keeping is gaining an increasing interest in Sweden. During 2004 to 2010 the number of horses increased with 10 - 20 %, and was estimated to be 362 700 in 2010. Julmyra Horse Center (JHC), situated in Heby municipality, is a gated community for people sharing a large interest for horses and a vision of a sustainable horse management has been formulated. This study evaluates how the horse keeping of today at JHC, and how an expansion of the horse keeping may affect the risk of enhanced phosphorus load to the nearby lake system Vansjön ? Nordsjön.

Kvalitet i brödvete :

The quality of bread wheat is a large subject to study. The quality rests on two legs. The first one is the inheritance of specific characters, which can be influenced through plant breeding and type of cultivar. The other one is the environmental influences, such as crop rotation, nutrition, harvest and storage. The latter factors are possibly to affect through cultivation practices, while other factors are not possible to influence on for the grower, such as seasonal changes of weather and the soil content.

Fr?n verktyg till offerg?va. Dep?fyndens roll i V?nersn?s forna sten?lderslandskap, med fokus p? lihultkulturens rituella rum.

This thesis examines five deposits, some of which contain stone axes, at the settlement in V?nersn?s, Sweden. Two of them date to the late Mesolithic era. The aim is to explore the ritual world of the late Mesolithic in V?sterg?tland, Sweden and its relationship to the landscape.

Numerisk modell för global transport av spårämnen i atmosfären

The aim of this project was to develop a numerical model simulating the global transport of air pollution. The model currently used by SMHI, the Swedish Meteorological and Hydrological Institute, was intended to perform such simulations at regional scales. However, the usage of a grid based on longitudes and latitudes makes this model work poorly in global simulations. The problem with this grid is that the nodes are concentrated near the North and South Poles. Due to this characteristic, the Courant, Friedrich and Lewy-condition for numerical stability puts a sharp bound on the timestep length.

El nino- Southern ocsillation och de tropiska cyklonerna i Stilla havet

ReferatDe tropiska cyklonerna har både skrämt och fascinerat människor genomtiderna och det pågår en hel del forskning kring dem. I detta arbete studeras omEl niño?Southern ocsillation påerkar antalet, intensiteten eller livslägden pådetropiska cyklonerna i Stilla havet. Till detta anväds temperaturdata frå bojarsom den amerikanska väertjästen National Oceanic and AtmosphericAdministration placerat ut i Stilla havet och insamlad information kring detropiska cyklonerna. Studien baseras pådata frå en 15ås period under åen1995 till 2009.Studien visar bland annat att antalet tropiska cykloner påerkas relativt mycketav de olika faserna i El niñ? Southern oscillation.

Bok- och grankonkurrens i Sydsverige - markegenskaper och naturlig föryngring :

In southern Sweden, beech (Fagus silvatica) and spruce (Picea abies) are two species with similar demands on soil properties. With increased global warming and high acid deposition the future may bring larger areas were the two species are overlapping, competing for the same soil. The aim of this study was to compare spruce and beech concerning distribution, cultivation and soil properties. From available data comparisons were made between spruce and beech forests in Sweden. Soil analyses were made on samples from beech forest in southern Sweden, with and without natural regeneration of spruce.

Städer och planetära gränser : En utvärdering av Stockholms ochNorra Djurgårdsstadens påverkan påde planetära processerna

The concept of planetary boundaries was introduced in the year 2009 by a group ofresearchers led by Johan Rockström and Will Steffen. The group presented a draft of thelimits of the planet regarding nine Earth System processes concerning climate change, oceanacidification, stratospheric ozone depletion, atmospheric aerosol loading, interference with Pand N cycles, global freshwater use, land-system change, rate of biodiversity loss andchemical pollution. The starting point for the study presented in this report was that asustainable development only can be achieved if humankind stays within the boundaries. It istherefore, based on the ongoing urbanization, relevant to evaluate how cities affect the EarthSystem processes. The aim of the study was to investigate if Stockholm Royal Seaport (NorraDjurgårdsstaden), a district in the northeast of Stockholm with a clear environmental profile,affects the Earth System processes less than Stockholm in general does.

Storjuktan ? Rekonstruktion av ett sekels kvicksilverbelastning. : En undersökning av kvicksilverkoncentrationer i daterat bottensediment.

The aim of this study was to examine the current and historic mercury(Hg) load of the lake Storjuktan due to its recent exposure to a local potential source of Hg in form of the Sulphide mine Blaikengruvan(2006) and an earlier potential sources of Hg-load, the damming of the lake(1960s). Sediments were extracted using a HTH-sampler, freeze-dried, and analyzed for tot-Hg, LOI and activity of 210Pb and compared to samples extracted prior to the opening of the mine(2006). Constant initial concentration (CIC)-dating model was used for dating the samples. Low levels of Hg (100ng/g) were found throughout the lakes sediment. The highest levels of Hg(220ng/g) was detected at a depth of 4-5cm dating back to the mid 1970:s, suggesting that increased levels of atmospheric Hg rather than damming of the lake has caused the increase of Hg.

Vattennivåförändring kring Gamla Uppsala och dess påverkan på människan

ReferatDe tropiska cyklonerna har både skrämt och fascinerat människor genomtiderna och det pågår en hel del forskning kring dem. I detta arbete studeras omEl niño?Southern ocsillation påerkar antalet, intensiteten eller livslägden pådetropiska cyklonerna i Stilla havet. Till detta anväds temperaturdata frå bojarsom den amerikanska väertjästen National Oceanic and AtmosphericAdministration placerat ut i Stilla havet och insamlad information kring detropiska cyklonerna. Studien baseras pådata frå en 15ås period under åen1995 till 2009.Studien visar bland annat att antalet tropiska cykloner påerkas relativt mycketav de olika faserna i El niñ? Southern oscillation.

Grovfodermajs : från odling till utfodring av växande nötkreatur

The use of forage maize has increased over the last years. The aim of this litterateur review was to summarize a part of the research that has been conducted on forage maize for growing cattle, including cultivation and conservation of the maize. The forage maize is planted in April or the beginning of May when the temperature in the soil is between 6 and 10°C. Maize needs high temperatures and much water. Maize is harvested in the autumn when the dry matter (DM) is more then 30% or the plants have been exposed to the first frost in the autumn.

Sjunkande pH i Västerbottens humuslager : en kvantitativ analys

Acidification is a central concept in the environmental debate. The effect of acidification of the soil is a matter of a decreasing amount of cations and thereby a decreasing ability to resist a supply of hydrogen ions to the soil. Acidification has gradually increased in the O horizon in Västerbotten over a 30-year period from the 1970th to the 1990th. The aim of this study was from inventories of The Swedish National Forest Soil Survey and The Swedish National Forest Inventory explain and quantify the acidification that has occurred in the O horizon of two regions in the north of Sweden. Data from SMHI, The Swedish Meteorological and Hydrological Institute, has also been used.

Undersökning av sambandet mellan strålningstemperatur och NDVI i Sahel

Several studies have analysed the relationship between Normalised DifferenceVegetation Index (NDVI) and radiative surface temperature. A main goal for moststudies have been to find the best method for carrying out land cover classificationsand to study land cover changes, based on a combination between the twoparameters. Since atmospheric components have a significant influence on bothparameters, most applications were based on multi-temporal data. The quality of theindividual values in such a combination is improved, but the biophysical justificationis uncertain. This study presents a different method, based on only the combination ofvalues that have been registered the same day and about the same time of the day.125 daily images of NDVI and 250 images of radiometric temperature were used inorder to analyse the relationship between (1) NDVI and radiative temperature and (2)NDVI and relative temperature difference between early morning and mid-day.Results between NDVI and radiative temperature show a significant negativecorrelation on areas where a distinct growing season develops, and a strong positivcorrelation where vegetation is abscent throghout the season.

Tillståndskontroll av vätskeringpumpar

Bakgrunden till detta examensarbete är ett behov av att införa vibrationsmätning i form av ett tillståndsbaserat underhåll vid AB Sandvik Coromants produktionsanläggning i Gimo. Underhållsarbetet på AB Sandvik Coromant i Gimo bedrivdes vid tidpunkten för studien som avhjälpande och förebyggande med olika fasta underhållsintervaller. Att införa tillståndsbaserat underhåll skulle kunna reducera kostnaderna, samt medföra en ökad uppföljning av varje maskin i form av hälsotillstånd. Målsättningen med examensarbetet var att utvärdera vibrationer som mätmetod. Arbetet har innefattat fyra, huvudsakliga moment.

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