Sökning: "anthropogenic"

Visar resultat 11 - 15 av 491 avhandlingar innehållade ordet anthropogenic.

  1. 11. A palaeolimnological study of the anthropogenic impact on dissolved organic carbon in South Swedish lakes

    Författare :Petra Bragée; Kvartärgeologi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; DOC; Brownification; Landscape Reconstruction Algorithm; Land-use changes; Lake sediments; Anthropogenic impact;

    Sammanfattning : During the past three decades, increases have been observed in dissolved organic carbon (DOC) concentrations and colour in the surface waters of lakes and rivers in parts of Europe and North America, raising concern about the effects on the quality of aquatic environments with consequences for biodiversity, resource availability and recreational use. Various hypotheses have been put forward to explain the recent increases in DOC concentration and numerous studies have been published linking them to declining anthropogenic atmospherically deposited sulphur. LÄS MER

  3. 12. Importance of tannins for responses of aspen to anthropogenic nitrogen enrichment

    Författare :Franziska Bandau; Benedicte Albrectsen; Michael Gundale; Lisbeth Josson; Umeå universitet; []
    Nyckelord :LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; aspen; foliar condensed tannins; genetic variability; anthropogenic nitrogen enrichment; plant growth; plant defense; litter decomposition; Populus tremula; asp; kondenserade tanniner; genetisk variabilitet; antropogent kväve; tillväxt; växtförsvar; förna nedbrytning; Populus tremula; Environmental Science; miljövetenskap; ekologisk botanik; Ecological Botany; Entomology; entomologi; Physiological Botany; fysiologisk botanik; Population Biology; populationsbiologi;

    Sammanfattning : Boreal forests are often strongly nitrogen (N) limited. However, human activities are leading to increased N inputs into these ecosystems, through atmospheric N deposition and forest fertilization. LÄS MER

  4. 13. Sex in Murky Waters : Anthropogenic Disturbance of Sexual Selection in Pipefish

    Författare :Josefin Sundin; Anders Berglund; Gunilla Rosenqvist; Bob Wong; Uppsala universitet; []
    Nyckelord :Mating system; Mate choice; Courtship; Eutrophication; Turbidity; Hypoxia; Ocean acidification; Syngnathidae; Biologi med inriktning mot zooekologi; Biology with specialization in Animal Ecology;

    Sammanfattning : Animals experience variation in their environment because of natural changes. However, due to anthropogenic disturbance, the speed and severity of these changes have recently increased. This thesis investigates how reproductive behaviours may be affected by human induced environmental change. LÄS MER

  5. 14. Environmental levels of thallium : influence of redox properties and anthropogenic sources

    Författare :Ulrika Karlsson; Stefan Karlsson; Anders Düker; Roger Herbert; Örebro universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; thallium; Tl I ; Tl III ; separation; ion chromatography; fresh water; sediment; mine waste; fly ash; redistribution; ICP-MS; Environmental chemistry; Miljökemi; Kemi; Chemistry;

    Sammanfattning : Thallium is a highly toxic element that humans are exposed to mainly by consumption of drinking water and vegetables grown in soil with high thallium content but also through inhalation of particles in the air. Thallium is also present in fossil fuels, alloys, and in electronic utilities. LÄS MER

  7. 15. Geochemistry of Trace Elements in the Bolivian Altiplano : Effects of natural processes and anthropogenic activities

    Författare :Oswaldo Eduardo Ramos Ramos; Prosun Bhattacharya; Jorge Quintanilla; Roger Thunvik; Jochen Bundshuh; Maria Eugenia Garcia Moreno; Luiz R.G. Guilherme; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Arsenic; Bolivian Altiplano; Eastern Cordillera; Trace elements; Surface water and shallow groundwater; Soils and crops.; Mark- och vattenteknik; Land and Water Resources Engineering;

    Sammanfattning : The occurrence of As in groundwater in Argentina was known since 1917; however, the occurrence, distribution and mobilization of As and other trace elements (TEs) in groundwater in the Bolivian Altiplano are still quite unknown. An investigation applying a geochemical approach was conducted in the Poopó Basin and Lake Titicaca to understand processes of TEs in different systems such as water, soils, crops and sediments in mining areas. LÄS MER