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1336 Uppsatser om Catchment scale - Sida 1 av 90
Kvantifiering och kartering av föroreningstransport inom ett avrinningsområde
The aim with my master thesis is to develop and test the applicability of methods to quantify and map solute advective travel times and pollutant transport at the Catchment scale. Such quantification and mapping can increase the understanding of catchment-scale pollutant transport in general and contribute to the identification of the main sources of water pollution and the most efficient measures to reduce such pollution. The study area is the catchment of Oxundaån, about 20 km north of Stockholm. For detailed GIS modeling of water flow and catchment-scale contaminant transport in water, I´ve used new high-resolution elevation maps, land cover maps and soil maps combined with other available relevant data..
Tillämpning av en markprofilmodell för hydrologiska beräkningar i avrinningsområdesskala
There is a great need to reduce nutrient leaching from arable land into lakes and oceans. By using several different types of models it has previously been possible to describe nutrient losses in a catchment area with a minimum unit of sub-catchment level. At present, it is instead desirable to model a smaller catchment with an opportunity to re-connect the results to the corresponding fields in the catchment. Such models already exist but they are not fully able to properly describe Swedish conditions and land characteristics in our region.With the approach of creating such a model, SLU has developed a project with this work as its first stage. The model is expected to be created under the working name SWE-model which stands for Soil Water Environment and is in this first stage supposed to apply the SOIL model in Catchment scale. During the procedure to describe the first step in the process of developing such a model adapted to Swedish conditions and which works in the Catchment scale with an area of about 10-30 km2, focus has been set on calculating the transport of water flow from different hydrological response units. Regardless of the processes occurring in the soil after the water has been added, it is assumed that all the water which flows from each simulated unit is drained.In the first step the hydrologic response units were identified based on land use and soil type in the study area. With the help of a script with functions that retrieve and transform data, certain units were chosen for simulation. The script was also created in this project. Finally, the model results were aggregated and summarized for each unique unit, for each sub-catchment, and also for the whole catchment.From the results it is possible to see similarities in the flow dynamics between modeled and measured data. The efficiency coefficient has been calculated to correspond to the mean of the measured values for the whole simulation period. With an automated calibration process the model should be able to perform better. The volume error gives an indication of overestimation from the model..
Topografins inverkan på markvattenhalten i ett jordbruksdominerat avrinningsområde
Topography is an important parameter for catchment hydrology, since it is a driver for water flow. Moreover, topography serves as a basis for hydrological models, e.g. ?Top-model?, which is based on a topographical wetness index (TWI). Few studies of TWI have been conducted on agricultural Catchment scale.
Four fields were studied in a Swedish drained agricultural catchment in order to evaluate the influence of topography on soil wetness.
Märstaån ? ett vattenlandskap : Är våtmarker och dammar vägen framåt?
The overall aim is to examine how the European Union Water Framework Directive has affected the local water management in the catchment Märstaån situated in the eastern part of the lake Mälaren river basin, Sweden. The first part of the study gives an historical overview of the area with focus on how the old agricultural landscape was handling the nutrient load from farming activities by means of different kinds of wetlands. By using the concept of the procedural landscape, introduced by Torsten Hägerstrand , together with historical maps with dates starting from the 17th century, the pre-modern landscape is analyzed. The second part is an investigation, based on qualitative data, on how the different actors in the catchment area work together to secure the water quality for the Märstaån river. The analysis shows that the Märstaån catchment river systems are mostly unchanged in the rural areas. The exception is the mainstream section of the Märstaån river running partly underground today and the Halmsjöbäcken river that is heavily affected by the Arlanda airport situated within the catchment area.
Hållbart jordbruk inom vattenskyddsområde : En studie om Sverige, Danmark, Frankrike och Tyskland
To guarantee protection of our drinking water, water catchment protections are established. These are divided into three different zones and in the first zone it is most likely that an activity, such as agriculture, will contaminate the water resource. Hence the activities are strongly regulated or banned. The EU communion is working towards a sustained water quality through several directives; Nitrate Directive, Waterframwork directives and Sustainable use of pesticide directive. The main purpose is to regulate the diffuse pollution from agriculture.This thesis is about how Denmark, Germany and France are working towards a sustainable agriculture within water protection areas.
Konduktivitet i vattendrag som indikator på sura sulfatjordar
Increasing attention is being given to acid sulphate soils wherever they occur. The problems that leaching sulphate soils gives with significant lowerings of pH and mobilization of heavy metals influence large spectra of our society from fisheries to agriculture to construction. Mapping these soils is consequently of great importance and the methods of doing this is very much lacking in function and precision. This study was therefore carried out to investigate whether conductivity in running water can be used as a simple instrument to identify acid sulphate soils in the catchment. 31 coastal streams in the county of Västerbotten were analyzed for different catchment properties such as occurence of marine sediments and basic water chemistry including conductivity and sulphate.
Spatiella mönster och lager av organiskt klor och klorid i barrskogsjord i sydöstra Sverige
The concentration and storage of organic chlorine and chloride were determined in soil, to a depth of 40 cm, in a coniferous forest in the Stubbetorp catchment area in south-east Sweden. Also, the spatial distribution of the two forms of chlorine was determined. Soil samples were collected at 49 of the nodes in a grid with approximately 105 m between the nodes. The analysis of spatial variability suggested that no spatial autocorrelation was present either within the variable organic chlorine or chloride. This means that no sample was more influenced by another nearby sample, as compared to other samples further away.
Effekter av kalavverkning på mindre boreala sjöars vattenkvalitet
Forestry is an important industry in Sweden, with clear-cut as the most commonly used method for harvesting. Here the long-term impact of clear-cut on lake water quality (dissolved organic carbon (DOC), nitrogen, phosphorus and pH) has been investigated, based on 23 lakes sampled during autumn. Data for additional 15 lakes sampled for the Swedish monitoring program were also used. Lakes were classified as 5, 25, 40 and 60 year based on data of the forest age in the catchment, gathered from the Swedish national forest inventory. Clear-cut lakes were classified as 5 years (>20% of the catchment clear-cut during the last 10 years).
Är Lerbodaälven verkligen en problemälv? : undersökning av fosforhalter
Lerbodaälven is a river in the municipality of Kil which, due to high phosphorus content is not meeting the requirements for good ecological status according to the Water Framework Directive. The purpose of this report is to investigate the causes for the high content of phosphorus that has been measured in Lerbodaälven between 1995-2010. Four questions will be answered in this report.
1. Does the sewage treatment work affect the phosphorus level in Lerbodaälven?
The result from the time series analysis shows that the sewage treatment works have a small impact on the phosphorus level in Lerbodaälven.
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.
Skalans betydelse vid utformning av stadsrum
When one experiences a place, it is a complex composition of both social and spatial factors.One of these spatial elements, is scale, which is influenced both by the room size and itsproportions. This paper aims to explore both large and small scale concepts and thus increasethe understanding of how scale directly and indirectly affects the experiences and uses ofurban space.First, is a theoretical discussion of scale in relation to aesthetics and the differencesbetween real scale and perceived scale. Next, is an analysis of spatial perception usingexamples from two existing sites. One, which is understood to have been planned in a largescale and one which is understood to have been planned in a small scale.When preparing this paper, the focus quickly became the importance of scale as itrelates to street spaces. The perception of a street usually takes place while in motion, whichforces it to be perceived in sections.
Om behovet av ett avrinningsområdesanpassat skogsbruk
The Swedish forest have about 100 000 km of watercourses and it?s an important structure in Swedish landscapes and catchments. In some of the watercourses lives spieces like the freshwater pearl mussel (Margaritifera margaritifera) and brown trout (Salmo trutta) which both are sensitive for inteference from the forestry. The new EU water framework directive has a goal that all surface water will have high or good ecological- and good chemical status at latest by the 22nd December of 2015.
The study has been made in the catchment of Håltjärnsbäcken and it is from a national perspective one of the most valuable streams in Sweden and which also have been included in a LIFE-project. The catchment is situated within the Eco-park of Malingsbo-Kloten and managed by Sveaskog AB.
Normering av Rösthandikappindex och Halsskalan för personer över 65 år i Sverige.
The population over 65 years of age is increasing and health in elderly has been a subject of research for decades but voice function and vocal health has not been prioritized. The purpose of this study is to obtain reference value for the Swedish version of Voice Handicap Index (RHI) and the Throat Scale among people over 65 years of age and assess voice function and vocal health for this age group. The questions were as followed:1) What is the reference value of RHI for people over 65 years of age? 2) What is the reference value of the Throat Scale for people over 65 years of age? 3) Is there a correlation between a self-rated VA-scale on the perceived degree of voice problems, and the self-rated RHI-/Throat Scale result? 4) Does age, gender or previous profession matter for the self-perceived voice?In total 100 individuals participated in the study, 50 women and 50 men, between 65 and 92 years old. The reference value of RHI for people over 65 years of age was 13,4 points and the reference value for the Throat Scale was 7,7 points.
Användning av smärtskala på marsvin ? experimentell studie i klinikmiljö
Assessing and measuring post-operative pain in all animals is a challenge, but doing it in small mammals, for example guinea pigs, presents an even larger difficulty. Validated pain scales developed for use in dogs in clinical practice are currently available, but no such scale has been widely accepted for use in guinea pigs in the veterinary setting. In this experimental study, six guinea pigs that had undergone surgery and anaesthesia were observed for behavioural changes that could be associated with pain. The six guinea pigs were also given pain scores with the use of Colorado State University Feline Acute Pain Scale (CSU-APSF), a scale which uses both behaviour when not handled, body tension and response to palpation to evaluate pain intensity. The six guinea pigs showed a number of different behaviours, for example rigid posture, fixed stare and ?wet dog response? (the body is vigourosly shaken), that could be associated with pain.
Våga ta steget!: En studie om de attraktiva produktkategorierna
This paper studies patterns of consumption within a product category. Using make-up as a base for the study, we applied the Mokken Scale to examine if consumers follow a hierarchical pattern when buying items within the product category. Based on a survey of 250 female respondents, we establish a hierarchic scale for consumption. Assuming generally accepted attributes for determining physical attractiveness, the results of the Mokken Scale study were cross referenced with a survey among 200 male and female respondents. Students were asked to evaluate pictures of a model using different combinations of make-up, i.e.