Sökning: "Lake restoration"

Visar resultat 1 - 5 av 12 avhandlingar innehållade orden Lake restoration.

  1. 1. Long-term development of subalpine lakes : effects of nutrients, climate and hydrological variability as assessed by biological and geochemical sediment proxies

    Författare :Manuela Milan; Christian Bigler; Monica Tolotti; Richard Bindler; Krystyna Szeroczyńska; Atte Korhola; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Paleolimnology; diatoms; Cladocera; sub-fossil pigments; geochemistry; wavelengthdispersive X-ray fluorescence spectroscopy; Lake Garda; Lake Ledro; reference conditions; nutrient enrichment; climate change; hydrological regime.;

    Sammanfattning : Sediment records of two Italian subalpine lakes (Lake Garda and Lake Ledro) were analyzed in order to reconstruct their ecological evolution over the past several hundred years. A multi-proxy and multi-site approach was applied in order to disentangle the effects of local anthropogenic forcings, such as nutrients, and climate impacts on the two lakes and their catchments. LÄS MER

  3. 2. Plankton communities in a changing world - responses to temperature, brownification and lake restoration

    Författare :Mattias Ekvall; Enhet akvatisk ekologi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Climate change; temperature; warming; brownification; biomanipulation; zooplankton; cyanobacteria; microcystin; grazing; Daphnia;

    Sammanfattning : The effects of increasing temperatures, in light of climate change, have been a well-studied topic during the past decades. However, aquatic ecosystems are also faced with additional challenges such as increasing water colour, known as “brownification”. LÄS MER

  4. 3. The palaeolimnological record of regime shifts in lakes in response to climate change

    Författare :Linda Randsalu Wendrup; Kvartärgeologi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; palaeolimnology; regime shifts; thresholds; alternative stable states; climate change; ecosystem dynamics; diatoms; hydrocarbons; monitoring; lake sediments; shallow lakes; 8.2 ka event;

    Sammanfattning : Regime shifts in lake ecosystems can occur in response to both abrupt and continuous climate change, and the imprints they leave in palaeolimnological records allow us to investigate and better understand patterns and processes governing ecological changes on geological time scales. This thesis aims at investigating palaeolimnological records of regime shifts in lakes during the Holocene to explore how lake ecosystems responded to climate changes and anthropogenic activities and to identify thresholds or tipping points that produced regime shifts. LÄS MER

  5. 4. Restoration of Nutrient Rich Lakes - Towards Better Understanding of Sediment Phosphorus Availability and Management

    Författare :Oskar Agstam; Sveriges lantbruksuniversitet; Sveriges lantbruksuniversitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : Lakes are important for many reasons as they provide valuable ecological and human services, such as drinking water and recreational use. Eutrophication, a result of excess nutrients (e.g. phosphorus (P)) in lakes, is a threat to these resources, causing impairment of water quality. LÄS MER

  7. 5. Consumption patterns and excretion in aquatic food websenrichment

    Författare :Anders Persson; Enhet akvatisk ekologi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Hydrobiology; trophic interactions; translocation; biomanipulation; enrichment; phosphorus; model; marine biology; aquatic ecology; limnology; Marinbiologi; limnologi; akvatisk ekologi;

    Sammanfattning : This thesis links biogeochemical cycling to classical ecology. Predictions derived from food chain theory, based on Lotka-Volterra type of interactions, were tested in aquatic environments with the main hypothesis that consumers affect lower levels of organization by both predation and excretion of limiting nutrients. LÄS MER