Search for dissertations about: "seasonal variations"

Showing result 1 - 5 of 159 swedish dissertations containing the words seasonal variations.

  2. 1. Seasonal variations in general activity, behaviour and cutaneous glandular structures in reindeer (Rangifer tarandus L.)

    Author : Torgny Mossing; Umeå universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Androgen; Cervidae; dermal glands; locomotor activity olfactory communicatiorL pheromones; photoperiod; rein deer; rut; seasonal variations;

    Abstract : The locomotor activity of the reindeer is separated into a diurnal and a nocturnal phase which, in turn, consists of a  number of short-term activity bursts. The onset and termination  of diurnal and nocturnal activity are largely in synchrony  with sunrise and sunset. READ MORE

  4. 2. Lateral movements versus stationarity : adaptive alternatives in benthic invertebrates to the seasonal environment in a boreal river

    Author : Tommy I. Olsson; Umeå universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Benthic invertebrates; cold-hardiness; ice; migrations; overwintering; river; seasonal variations; spatial distribution; spring flood; water level;

    Abstract : Benthic invertebrates inhabiting boreal rivers are exposed to very large seasonal variations in their physical environment. The extremes are in winter when the littoral area freezes solid and in spring when water flow increases rapidly. READ MORE

  5. 3. The Carbon Dioxide System in the Baltic Sea Surface Waters

    Author : Karin Wesslander; Göteborgs universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Baltic Sea; carbon dioxide; pCO2; total alkalinity; pH; air-sea gas exchange; inter-annual; seasonal;

    Abstract : The concentration of carbon dioxide (CO2) in the atmosphere is steadily increasing because of human activities such as fossil fuel burning. To understand how this is affecting the planet, several pieces of knowledge of the CO2 system have to be investigated. READ MORE

  6. 4. Generation of urban runoff : Seasonal and climate change perspective

    Author : Shahab Moghadas; Claes Hernebring; Luleå tekniska universitet; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; VA-teknik; Urban Water Engineering;

    Abstract : Runoff generation in cold regions is characterized by snowmelt contributions to runoff during the periods of thawing and changing runoff patterns due to frozen ground. This thesis project aimed at addressing these challenges by advancing the procedures for winter urban runoff computations and the assessment of control measures during the winter/spring period, when the snowmelt and frozen soils dominantly impact runoff generation in the current and future climates. READ MORE

  7. 5. Evaluation of Dust Suppressants for Gravel Roads : Methods Development and Efficiency Studies

    Author : Karin Edvardsson; Björn Birgisson; Andrew Dawson; KTH; []
    Keywords : Gravel road; dust; particulate matter; PM10; horizontal dust diffusion; deteriorations; maintenance; dust control; dust suppressants; efficiency; application rate; leaching; residual concentration; seasonal variations; salt solution; solid salt; calcium chloride; magnesium chloride; lignosulphonate; polysaccharide sugar ; bitumen emulsion; rape oil; starch; surfactant; mesa; clay; fine material content;

    Abstract : Approximately 75 percent (300 000 km) of the total Swedish road network and 20 percent(20 000 km) of the national road network consists of gravel roads. One of the most significantproblems associated with gravel roads is traffic-generated dust emission, which contributes tothe deterioration of the road surface and acts as a major source of particulate matter releasedinto the atmosphere, thereby involving public economics, road safety, human health, andenvironmental quality. READ MORE