Sökning: "pond"
Visar resultat 21 - 25 av 71 avhandlingar innehållade ordet pond.
21. Water and sediment quality of urban water bodies in cold climates
Sammanfattning : The aim of this study was to investigate and quantify pollution impact on urban waterbodies in cold climates and to find out which complex processes and influencing factors causetrapping or spread of pollutants. In order to do that water, sediment and porewater samplesfrom bays and stormwater ditches in Luleå, northern Sweden, and from an artificialstormwater pond in Sollentuna, south-central Sweden, were analysed for LOI, trace metalsand PAHs. LÄS MER
22. Invasion of top and intermediate consumers in a size structured fish community
Sammanfattning : In this thesis I have investigated the effects of invading top and intermediate consumers in a size-structured fish community, using a combination of field studies, a lake invasion experiment and smaller scale pond and aquaria experiments. The lake invasion experiment was based on introductions of an intermediate consumer, ninespine stickleback (Pungitius pungitius L. LÄS MER
23. Effects of temperature and terrestrial carbon on primary production in lake ecosystems
Sammanfattning : Climate warming is predicted to affect northern lake food webs in two ways: (1)directly via changes in water temperature and ice conditions, and (2) indirectlyvia changes in catchment characteristics and processes that influence input ofallochthonous coloured dissolved organic matter (cDOM) and nutrients. Input ofcDOM increases carbon dioxide (CO2) availability, causes brownification andreduced light conditions, and may increase nutrient availability especially forpelagic primary producers. LÄS MER
24. Trace metals in swale soils and sediments from gully pots and stormwater management ponds
Sammanfattning : Three commonly used drainage system components, with considerably different characteristics and roles in stormwater management, were studied and reported on in this thesis: (i) grass swales, (ii) gully pots (GPs), and (iii) stormwater management ponds. With time, solids and associated pollutants accumulate in these components, and regular maintenance is needed to ensure that their design functions, including protection of the environment, are sustained. LÄS MER
25. Geochemical processes in sulphidic mine tailings : field and laboratory studies performed in northern Sweden at the Laver, Stekenjokk and Kristineberg mine-sites
Sammanfattning : This thesis presents geochemical, mineralogical and laboratory studies of unremediated and remediated tailings at two abandoned mine sites; at Laver and Stekenjokk and at one active mine site; the Kristineberg mine. At Laver the Cu released from oxidation is enriched in an enrichment zone just below the oxidation front. LÄS MER
