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169 Uppsatser om Lake sediments - Sida 7 av 12

Utsläpp av växthusgaser under islossning i små boreala sjöar

Freshwater ecosystems have long been neglected as an important part of the global carbon cycle. However, research shows that most of the world?s lakes are net-heterotrophic and consequently emitters of greenhouse gases to the atmosphere. In many boreal and north-temperate lakes, most of the yearly emissions usually occur in spring, shortly after ice-thaw. The aim of this study was to quantify the flux of carbon dioxide (CO2) and methane (CH4) in three boreal lakes, during this annual event.

Sedimentprovtagning av dagvattendammar som ett alternativ till flödesproportionell vattenprovtagning

Stormwater run-off from surfaces such as roads or rooftops is often polluted with heavy metals and nutrients. Many of these substances can cause great damage in biota if they end up in the recipient. In Sweden constructed wetlands and ponds for treatment of stormwater are frequently used, since research has shown that these treatment ponds are reducing stormwater pollution considerably to a low cost. The knowledge of these pollutant removal mechanisms and how follow-up and assessment of the ponds should be performed is still limited.To determine the pollutant removal efficiency of the stormwater ponds it is recommended that flow-weighted water samples are collected from both the inflow and the outflow of the pond. This method demands considerable resources of time and money for installations and analysis.

Bottenfaunan i Stensjöån och dess tillflöde Bokån : - en undersökning av tre lokaler

The purpose of this study has been to examine whether the bottom fauna of the stream Stensjöån, has been negatively influenced since the harvesting of peat began on the nearby peat moss Skäftesmyr or not. Comparison has been made with the results of index calculations from earlier examinations in the stream, two calculated indexes has been made, Danish fauna index and ASPT-index. The sampling was made with the kick sampling method, SS-EN 27 828. Three locations were chosen for the examination, one upstream from the peat moss, one just downstream from where the brook from the peat moss joins Stensjöån and a third location near the outlet of the stream to the lake Stensjön. The samples were sorted and the found animals identified to the taxonomic level required for the calculation of the two indexes.

Lust att lära sig läsa : En jämförelse av två olika läsinlärningsmetoder; ljudmetoden och Whole language (kiwimetoden)

AbstractMy purpose with this study was to learn more about different ways to teach children how to read and to investigate how teachers can use more fiction when they teach.During the years that I have been working in school, I have only met teachers who use a method that is built on sounds. The children learns to read from books where the words is not put in their right purpose; for example; we can se a sun, a dear looks down in a lake.After my teacher-education in literature I became more and more interested in if it could be possible to use more fiction when you teach children how to read. I also wondered if it was possible to find readers where the sentences are put in a meaningful story.I heard of a method called Whole Language, or the kiwi-method and I decided to find out more about that method. I decided to make a comparison between the ?sound-method? and the Whole Language-method.I have been using qualitative interviews with both children and teachers with experience from these different ways of teaching.

En ängel och en demon. En idéanalytisk studie om tendensromanen En natt vid Bullar-sjön av Emilie Flygare-Carlén.

The purpose of this master?s thesis is to describe by a gender approach what ideas and values are expressed in the novel One Night at Bullar Lake and how they do coincide to a tendency. We also want to discuss authority and class divisions and how these can be connected to the novel and the author. Our final question is to examine in what way the voice of the female author is represented in the novel. To approach our material we use Yvonne Hirdman?s theories about the construction of sexes and Susan Sniader Lanser?s work about voices of female authors, as well as Horace Engdahl?s studies about the silent voice in literature.

Vad betyder min novell? : Författaren tolkar sin okända text

All my short stories have been written in an intuitive way according to which no outline of characters, intrigue or plot was made in advance. A consequence of this process is that not even myself as the author is aware of the meaning of the texts and therefore I too have to interpret the stories. Because of the character of the text, I use an analysis of archetypes according to C. G. Jung?s analytic psychology.

Hemoglobinkoncentrationen och dess påverkan på individens känslighet för AMS vid höghöjdsvistelse.

Kroppens prestation försämras vid höghöjdsvistelse pga. syrebrist och individer kan drabbas av akut höjdsjuka (AMS). Samtidigt acklimatiserar sig kroppen genom att bl.a. öka syreupptaget som kompensation för det låga syretrycket. Studiens syfte var att undersöka hur hemoglobinkoncentrationen (Hb) påverkas av hög höjd och om det finns någon korrelation mellan Hb i vila eller Hb-ökningen under arbete tillika individers välmående på hög höjd.

Hur såg Birkas hamn ut och vilka transporter behövdes?

What is located on the bottom in the water outside of Birka? Remains of a water palisade or jetties and other constructions.Birka a Viking Age town that existed between AD 750 and 975 was located on the northwestern part of the small island of Björkö, in the Mälar archipelago of the Baltic Sea in Sweden. The Town was protected onshore by a hill fort and a town rampart. It is a widely spread assumption that Birka had a water palisade as a part of its defense. There are logs and other remnants on the bottom of the lake dating back to the Viking age.

Dagvatten i Märsta : förslag till anläggning för ekologisk hantering samt metodöversikt

Stormwater in urban areas has been treated as a problem for a long time. The large proportion of impermeable surfaces inhibits the water from infiltrating in the ground to the same extent that it does in nature. This causes intensive surface flow during rain, which in turn causes inconveniences such as decreased accessability, floods and increased risk of desease spreading. Drainage through pipes is the traditional and usually functional metod for storm water disposal. That is as long as water flows are moderate. But precipitation varies naturally in amount and intensity and additional impermeable surfaces make some pipes insufficient for heavy or lasting precipitation.

Lokala skillnader i konsumtion av påväxtalger och terrestra löv hos en differentierad population av Asellus aquaticus

That ecological and evolutionary processes can take place on the same time scale is a recent insight. Today we also know that they are directly linked to each other. In the lake Tåkern, in year 2000, there was a structural change when phytoplankton declined and submerged vegetation, mainly stoneworts began to spread. This led to evolutionary changes in the aquatic sowbug, Asellus aquaticus which had previously been limited to the reed, most likely feeding on detritus. But then, sowbugs could exploit the new habitat in stoneworts and a new food resource in terms of periphyton.

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).

Genomgång av kemikalieförteckning som exempel på uppströmsarbete : en identifiering av utfasningsämnen i spillvattnet

Benthic invertebrates play important roles as feeding resources for many organisms in different food webs. Shifts in predation of these organisms can generate cascading effects and potentially lead to the disappearance of one or more species from a site. Cascading effects can bring impacts to organisms who aren?t even directly involved, why studies in this field are important for understanding sudden changes in ecosystems. I examined the predation from fish and waterfowl on benthic invertebrates in the shallow and eutrophic Lake Tåkern in the plains of Östergötland County, southern Sweden.

ALK?RR - K?LLA ELLER S?NKA F?R V?XTHUSGASERNA METAN OCH LUSTGAS? Empirisk studie av v?xthusgasutbyte i kustn?ra alk?rr p? den svenska V?stkusten.

Due to global climate change and the rising levels of greenhouse gases (GHG) in the atmosphere, the interest for seeking solutions for mitigation has increased. While much attention has been directed towards technical solutions such as carbon capture and storage (CCS), biogenic carbon sinks has also garnered significant attention. Previous studies have shown that coastal ecosystems such as seagrass meadows and mangroves have a much greater capacity for storing carbon (C) compared to terrestrial ecosystems. That raises the question if other coastal ecosystems, such as coastal wetland forests, that previously haven?t been considered as blue carbon habitats also contribute to coastal carbon sink capacity.

Metodik för bestämning av åkerdikens status : fallstudie av ett dike i Munktorps socken

Agricultural drainage ditches are links between fields, lakes and oceans, having the potential to transport e.g. sediment and nutrients. When in a good condition, drainage ditches can act as sinks for e.g. phosphorus and sediments and prevent eutrophication downstream. The aim of this study was to determine the condition of one agricultural drainage ditch and to come up with suggestions for appropriate measures. The aim was also to determine which of the ditch?s properties that were possible to evaluate visually, which processes they represented as well as which properties required complementary physical analysis. This in order to contribute to the work of developing a method for determining the status/condition of agricultural drainage ditches.

Trattbägarkeramik i Väte : när jordbruket kom till Gotland

This essay is a study and analysis of the funnel beaker pottery at Gullarve 1:13 in Väte parish. The purpose of the study is to analyse the chronology of the settlement by determine the distribution, stratigraphic context and the ornamentation of the pottery. Another purpose is to discuss the geographical location of the settlement in the landscape.In this essay a short review of the pottery and the funnel beaker culture as well as a description of the pottery from the archaeological excavation from 1984 at Gullarve 1:13 is presented. Since the documentation of the archaeological excavation from 1984 is missing or is very inadequate, no spatial analysis can be carried out. The distribution of the pottery can?t contribute to the result of the essay, though if possible it probably would have provided some interesting results.

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