Sökning: "regulated river"

Visar resultat 1 - 5 av 30 avhandlingar innehållade orden regulated river.

  1. 1. Indirect effects of river regulation : consequences for landbirds of reduced numbers of aquatic insects

    Författare :Darius Strasevicius; Björn Malmqvist; Tapio Eeva; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Boreal region; Simuliidae; Leucocytozoon; pied flycatcher; aquatic insects; breeding success; blood parasites; bird communities; river regulation; impoundment; Biology; Biologi;

    Sammanfattning : Abstrakt: Jag har undersökt hur älvreglering påverkar mängden knott (Tvåvingar: Simuliidae) längs flera norrlandsälvar och vilka konsekvenser denna påverkan får för den landlevande fågelfaunan. Studien visar att utbyggnad av älvar har en negativ effekt på mängden knott. LÄS MER

  3. 2. Re-establishment of connectivity for fish populations in regulated rivers

    Författare :Olle Calles; Larry Greenberg; Lars Nyberg; David Scruton; Karlstads universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Attraction efficiency; Connectivity; Flow regime; Hyporheic water quality; Nature-like fishway; Passage efficiency; Regulated river; Remedial measures; Salmo trutta; Biology; Biologi; Biology; Biologi;

    Sammanfattning : The hydropower industry has altered connectivity in many rivers during the last century. Many fish species depend on both an intact longitudinal connectivity to be able to migrate between spawning, feeding and winter habitats, and vertical connectivity for development and survival of incubating embryos and larvae in the gravel. LÄS MER

  4. 3. Impact of hydropower regulation on river water geochemistry and hyporheic exchange

    Författare :Dmytro Siergieiev; Hjalmar Laudon; Luleå tekniska universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; regulated river; hyporheic zone; hydraulic conductivity; clogging layer; Applied Geology; Tillämpad geologi;

    Sammanfattning : Hydropower regulation of rivers exhibits a threat to the riverine ecosystems. Fragmentation of flow, landscape disturbances, and water retention are key features of regulated catchments, resulting in reduced floods and geochemical tr¬ansport, non-natural water level fluctuations, and thus disturbed exchange between the river and the aquifer. LÄS MER

  5. 4. Hydrogeochemical effects of hydropower regulation on river-aquifer continuum in boreal rivers

    Författare :Dmytro Siergieiev; Hjalmar Laudon; Luleå tekniska universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Geochemistry; hyporheic zone; hydrology; riparian zone; Element transport; Lule River; Kalix RIver; Northern Sweden; Earth sciences; Applied Geology; Tillämpad geologi;

    Sammanfattning : Hydropower infrastructure affects many large rivers worldwide, threatening riverine and coastal ecosystems by fragmenting flow, disturbing landscapes and water retention and altering sedimentation and primary production. This thesis investigated major impacts of hydropower regulation on hydrological and geochemical processes in large boreal rivers. LÄS MER

  7. 5. Conservation of landlocked Atlantic salmon in a regulated river : Behaviour of migratory spawners and juveniles

    Författare :Anna Hagelin; Eva Bergman; Fleming Ian; Karlstads universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Atlantic salmon; conservation; migration; spawning; hydropower; competition; juveniles; brown trout; hatchery reared; fallback; delay; Biology; Biologi;

    Sammanfattning : Hydropower dams represent one of the major threats to river ecosystems today. The dams block migratory routes in many rivers, which is problematic for migratory fish species. Trap-and-transport may be an alternative to fish passage solutions, as a strategy to compensate for lost river connectivity. LÄS MER