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80 Uppsatser om Rain showers - Sida 5 av 6
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.
Urban dagvattenhantering med regnträdgårdar : gestaltningsförslag för Gårdsgatan i Norra Djurgårdsstaden
I Stockholm pågår i dagsläget ett stadsutvecklingsprojekt som kallas Norra Djurgårdsstaden, där visionen är att skapa en hållbar och klimatanpassad stadsdel i världsklass. Stockholms stad har valt att bland annat arbeta med olika former av ekologisk dagvattenhantering i projektet, där en av dessa former är regnträdgårdar. Syftet med denna kandidatuppsats är att ta fram ett gestaltningsförslag för hur dagvattenhanteringen kan lösas med hjälp av regnträdgårdar längs en planerad gata i Norra Djurgårdsstaden. Gestaltningsförslaget baseras på underlag av landskapsarkitektkontoret URBIO, som har erfarenhet av att arbeta med regnträdgårdar. Växter och växtbäddsmaterial
är huvudsakligen valda utifrån råd från sakkunniga.
För att få förståelse för regnträdgårdens funktion och uppbyggnad gjordes en litteraturstudie i arbetets inledande fas.
Resultat av tjugofem års mätningar av Cs-137-halter i älg i Uppsala län
At the end of April 1986 reactor number 4 of the nuclear power plant at Chernobyl explod-ed and large amounts of radioactive particles were then released into the atmosphere due to both the explosion as well as the consecutive fire of the graphite core. A cloud of radioac-tivity was spread over the northern hemisphere, including Sweden, due to the prevailing wind directions. The radioactive particles were washed out from the cloud by rain and snowfall in some areas of Sweden and deposited on the ground. The deposited radionu-clides, primarily cesium and iodine isotopes, were later absorbed into the soil and taken up by the roots of the plants. Some of these radionuclides, like 137Cs, still persist in some of the terrestrial ecosystems at relatively high concentrations which lead to contamination of the meat of moose, roe deer and wild boar even today.The two municipalities Heby and Uppsala, in the eastern part of central Sweden, experi-enced a relatively large deposition of 137Cs which resulted in high levels of 137Cs in moose and other game.
Structure and tree diversity of lowland limestone forest on Seram Island, Indonesia
There have previously been very few studies of forests on Seram Island in the Eastern Indonesian archipelago and none before on lowland limestone primary forests. The COLUPSIA project on collaborative land use planning has therefore chosen Seram as one of two project sites. The objective of the COLUPSIA project is to establish collaborative and equitable land use planning. In order to achieve its objective the COLUPSIA project aims to improve understanding of traditional resource management and how it interacts with governmental systems, as well as enhancing knowledge about tropical landscapes and ecosystem services.The aim of this study was to contribute to the COLUPSIA project through describing lowland limestone forest on Seram Island in respect to (1) forest structure, (2) tree species richness and (3) tree species composition. We set up 5 plots, each of 0.2 ha, at one site, Mawalai, and collected data on tree variables (tree diameter ?10 cm) as well as for some other life forms and environmental data.
Rehabilitation in a tropical secondary rain forest in Malaysian Borneo : early effects of canopy properties on light conditions at the forest floor
Tropisk regnskog i Sydostasien är ett av de områden som hyser störst biodiversitet i världen, av vilken stora ytor är hotat. Ön Borneo drabbades av en katastrof åren 1982-1983 efter att väderfenomenet El Niño orsakat torka med vidsträckta skogsbränder som följd. Detta lämnade stora ytor av Borneos skogar i ett undermåligt, sekundärt tillstånd. På grund av detta startades INIKEA projektet med syfte att rehabilitera skogar i regionen kring Tawau vid östkusten av delstaten Sabah i Malaysia. I denna studie undersökte jag resultatet av rehabiliteringsarbetet på krontaket i tre olika skogstyper genom att ta hemisfäriska foton med en digital systemkamera (DSLR).
Timeliness cost for agricultural sprayers : weed control in cereal crops
Evaluation of machinery costs is necessary for selecting appropriate farm machinery. Timeliness cost due to untimely operations is an important component of machinery costs. Timeliness costs can be high for crop sprayers, since pesticide application must be carried out within a short time interval. This Master thesis investigated the timeliness cost and the probability of a suitable workday for spraying. Timeliness factors were estimated for four different crops (oats, spring wheat, winter wheat and barley) using historical weed trial data.
Kan mjölkkors utnyttjande av vallprotein bli bättre? : utfodringsstrategier och konserveringsmetoder
The purpose with this literature study was to investigate the possibilities for improvement of forage protein in dairy cows with focus on feeding strategies and conservation of forage protein. The utilization of forage protein in dairy cows is often not that efficient as it could be. The feed crude protein consists of both true proteins and non protein nitrogen. The digestion of proteins in the rumen depends on the protein degradation rate and the ability of the microbes to synthesize microbial protein. The microbes need a balance between carbohydrates that provide them with energy and proteins that are degradable in the rumen.
Intensivt regn i Sverige 2009-2011 : En kartläggning över händelser av intensivt regn och dess konsekvenser
Sammanfattning Klimat- och sårbarhetsutredningen (SOU 2007:60) spår en framtid då Sveriges klimat till större del präglas av intensivt regn, och diskuterar konsekvenserna detta kommer innebära. Så väntas framtiden bli, men hur ser det ut idag? Syftet med uppsatsen är att kartlägga den samtida förekomsten av intensivt regn i Sverige och dess konsekvenser, i syfte att skapa en referenspunkt till diskussionerna om framtidens regnintensiva klimat och hur det kommer påverka samhället.Materialet studien bygger på har inhämtats från flera håll, men främst kommer det från SMHI, tidningsartiklar, räddningstjänster och kommuner. Sedan har en sammanställning gjorts där de identifierade händelserna analyserats kvantitativt och rumsligt. Studien är avgränsad till att endast inkludera händelser under sommarmånaderna juni, juli och augusti eftersom flest händelser av intensivt regn bedöms inträffa då.Resultatet visar stor geografisk spridning av inträffade regn, och liten kronologisk spridning.
Sammanvägda avrinningskoefficienter i rationella metoden : en jämförelse mellan idag och 1970-talet
Storm water is rain and melted snow that runs off, primarily from impervious surfaces.Future storm water management is facing the challenges of increased precipitation, asclimate changes, and increased areas of impervious surfaces due to the expansion anddensification of the cities. Impervious surfaces reduce the potential for water to infiltratein the ground leading to increased surface runoff and higher peak discharge.The runoff coefficient is closely related to the percentage of impervious surfaces andrepresents the maximum percentage of a catchment that can contribute to runoff. In thisstudy, the objective was to evaluate the weighted runoff coefficient for three differenturban types; apartment buildings, townhouses and residential areas and a comparisonbetween today and the 1970`s was made.The runoff coefficient was determined by manual mapping of the different surface typesin each area based on data in the form of orthophotos and aerial photographs. The surfacetypes that were mapped were asphalt, permeable areas, tiles, sand/gravel and roof.Tiles and sand/gravel were the most difficult surface types to map. In order to see towhat extent these categories influenced the weighted runoff coefficient a sensitivityanalysis was carried out and the runoff coefficient based on surface type was changed indifferent scenarios.The results of the sensitivity analysis showed that the surface types tiles and sand/gravelhad little impact on the weighted runoff coefficient which in mainly due to the fact thatthe percentage of these surfaces types of the total area is small.The result of the study showed that the largest change in the runoff coefficient occurredin residential areas where the increase in the percentage of impervious surfaces causedby new roofs in the form of porches and garages and from paved or tiled driveways.
Fröodling av Raj- och rörsvingel i Sverige
Festulolium (Festulolium) and tall fescue (Festuca arundinacea) has not been grown inSweden over a longer period. So far there is no greater area cultivated, but the area isincreasing. Festulolium and tall fescue are expected to eventually replace meadowfescue in many leyseed mixtures to dairy cows in southern and central Sweden. Tallfescue has in recent years become popular again. Festulolium is a hybrid betweenryegrass and fescue.
Dagvattendammars reningseffekt : påverkande faktorer och metodik för statistisk modellering
Storm water is defined as runoff from precipitation such as rain or snow. It is collected in sewage disposal systems and since it mainly originates from urban areas it can contain high levels of heavy metals, nutrients and oil etc. Polluted storm water is currently treated by different methods such as wet ponds, constructed wetlands and filter strips. This study investigates these methods, which in earlier studies have shown to give varying results regarding their treatment efficiency.This thesis has been written on commission of SWECO VIAK and was aimed at studying those parameters that may affect the treatment efficiency of nutrients and heavy metals in storm water treatment facilities (STF:s). Through literature studies the dominating treatment processes in ponds and wetlands were examined.
Impact of Eucalyptus plantations on pasture land on soil properties and carbon sequestration in Brazil
Soil organic carbon (SOC) stocks and fluxes in forest ecosystems are influenced by natural and human disturbances. In the tropical regions the highest impacts on disturbance in forest C cycles are related to human activities such as conversion of natural lands to cropland and pasture areas and to forest plantations. The disturbances in the forest C cycles will release CO2 emissions to the atmosphere triggering global warming. In this study the focus was set in subtropical soils in Brazil, south extreme region of Bahia. The aim of the study was to investigate whether reforestation of Eucalyptus plantations under former pasture areas will help mitigate climate change through carbon sequestration.
Nursing technique and growth environment of Rabbit fish (Siganus guttatus) in the area of Tam Giang lagoon, Thua Thien Hue
SummaryIn the area to the east of Hue city, in Vietnam, lays Tam Giang lagoon, one of Asia's largest lagoons, with an area of 22,000 hectares. This lagoon is suitable for aquaculture. One reason for this is because the salinity differs from sweet to salty in different parts of the lagoon. The Vietnamese Government advocates an increase in environmentally-friendly aquaculture and the fish Siganus guttatus (Rabbit fish) is a candidate for this. This fish eats mainly algae and can be cultivated in a polyculture.
Friluftsliv i gymnasiet: Elevers engagemang, motivation och erfarenheter : En kvalitativ intervjustudie om gymnasieelevers upplevelser av friluftsundervisning
The purpose of this study is to examine how outdoor education (friluftsliv) in upper secondary school is perceived by both students and teachers, and to identify the conditions that influence their motivation and commitment to participate in outdoor education activities. The study also aims to analyze the significance of students previous experiences on their perceptions of outdoor education in school. The following research questions were investigated: ? ? ? ?Which factors do students and teachers believe promote or hinder students engagement in outdoor education in upper secondary school? ? ? ? ?How do students and teachers explain the ways in which previous experiences of outdoor activities affect students engagement and motivation in outdoor education? ? ? ? ?How do students and teachers perceive that organizational conditions and teaching design influence the possibilities of creating meaningful outdoor education? The study is theoretically based on Self-Determination Theory (SDT) (Deci & Ryan, 2000) and Sense of Coherence (SOC) (Antonovsky, 1991). SDT was used to understand how autonomy, competence, and solidarity influence student?s motivation, while SOC highlights how comprehensibility, manageability, and meaningfulness shape student?s experiences of outdoor education.
Utveckling och tillämpning av en GIS-baserad hydrologisk modell
A distributed hydrological rainfall-runoff model has been developed using a GIS integrated with a dynamic programming module (PCRaster). The model has been developed within the framework of the EU-project TWINBAS at IVL Swedish Environmental Research Institute, and is intended for use in WATSHMAN ? a tool for watershed management developed at IVL. The model simulates runoff from a catchment based on daily mean values of temperature and precipitation. The GIS input data consist of maps with soil type, land-use, lakes, rivers and a digital elevation model.