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Visar resultat 1 - 5 av 42 avhandlingar som matchar ovanstående sökkriterier.

1. 1. Effects of solar radiation on the abiotic and bacterially mediated carbon flux in aquatic ecosystems

   Författare :Alexandre Magno Anesio; Biologiska institutionen; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; bacteria; dissolved inorganic carbon DIC ; bioavailability; aquatic macrophytes; photooxidation; detritus decomposition; Ultraviolet radiation; dissolved organic carbon DOC ; fungi; Hydrobiology; marine biology; aquatic ecology; limnology; Marinbiologi; limnologi; akvatisk ekologi;

   Sammanfattning : In this Thesis, I studied some of the current aspects of organic matter photochemistry. I analyzed abiotic phototransformations of several types of dissolved (DOM) and particulate organic matter (POM). I also evaluated the effects of phototransformation of several types of DOM on bacteria. LÄS MER

3. 2. Direct and indirect effects of fish predation and excretion in aquatic food webs

   Författare :José Luiz Attayde; Biologiska institutionen; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; marine biology; Hydrobiology; zooplankton; resilience; predation; phytoplankton; nutrient enrichment; nutrient recycling; interaction strength; herbivory; food webs; food chain; excretion; fish; detritus; detritivory; aquatic ecology; limnology; Marinbiologi; limnologi; akvatisk ekologi; Ecology; Ekologi;

   Sammanfattning : The aim of this thesis was to elucidate the mechanisms by which planktivorous fish can affect planktonic communities in lakes and how they may affect benthic communities through their effects on planktonic communities. In a laboratory experiment, nutrients released by fish increased algal biomass and altered phytoplankton community structure, suggesting that fish can affect phytoplankton by directly releasing nutrients. LÄS MER

4. 3. Polychlorinated biphenyls (PCB) in a river ecosystem

   Författare :Gudrun Bremle; Biologiska institutionen; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Hydrobiology; dredging; landfill; cleanup; remedial action; air; fish; sediment; Persistent organic pollutants; freshwater; marine biology; aquatic ecology; limnology; Marinbiologi; limnologi; akvatisk ekologi;

   Sammanfattning : Atmospheric deposition is one source of persistent pollutants such as polychlorinated biphenyls (PCB) in aquatic environments. Other point sources can also contribute to the PCB loadings in the water. LÄS MER

5. 4. Limitations and possibilities for microbial degradation of organic contaminants in aquifers

   Författare :Christel Carlsson; Biologiska institutionen; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Ekologi; mycology; Mikrobiologi; Hydrobiology; biodegradation; Organic contaminants; redox conditions; sorption; DOM; cometabolism; biomass; microbial activity; microbial community composition; Ecology; Microbiology; bacteriology; virology; bakteriologi; mykologi; virologi; aquatic ecology; marine biology; limnology; Miljökemi; Environmental chemistry; akvatisk ekologi; Marinbiologi; limnologi;

   Sammanfattning : Many factors can influence the rate of microbial degradation of organic contaminants in aquifers. Some of these factors, e.g. LÄS MER

7. 5. Invading Herbivory. Effects of the Golden Apple Snail (Pomacea canaliculata) in Asian Wetlands

   Författare :Nils Carlsson; Biologiska institutionen; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; gastropoda; invasive species; golden apple snail; herbivory; wetland functioning; biodiversity; sustainable control; indigenous predators; size-dependent competitive ability; akvatisk ekologi; limnologi; Marinbiologi; limnology; Hydrobiology; aquatic ecology; marine biology;

   Sammanfattning : The South American golden apple snail (Pomacea canaliculata) was intentionally introduced to aquacultures in South East Asia to produce snails for human consumption, but the aquatic snails soon escaped and started to consume large amounts of rice seedlings. The aim of this thesis was to quantify the effects of this invasive herbivore on aquatic plants in natural wetlands since previous research has focused on effects of the snail in rice fields. LÄS MER