Search for dissertations about: "vegetation survey"

Showing result 1 - 5 of 24 swedish dissertations containing the words vegetation survey.

  1. 1. Breaking the ice : effects of ice formation and winter floods on vegetation along streams

    Author : Lovisa Lind; Christer Nilsson; Christine Weber; Michael Scott; Umeå universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; anchor ice; climate change; in-stream; riparian; river ice; streams; vegetation;

    Abstract : Streams in cold regions are characterized by unique hydrological processes that control flow regime and water levels. One of the most important processes is the formation, growth and melting of different types of ice in and around the stream channel during winter. READ MORE

  2. 2. Boreal vegetation responses to forestry as reflected in field trial and survey data

    Author : Johan Bergstedt; Linköpings universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Logging; boreal forest; selective cutting; scarification; ground-layer flora; survey data;

    Abstract : This thesis had two objectives: the first objective was to evaluate the response of forest ground vegetation to selected forestry operations, i.e. cutting of different intensities and scarification; the second objective was to compare the use of survey data in vegetation research with that of more traditional research using field trials - i.e. READ MORE

  3. 3. Aquatic vegetation in coastal ecosystems : The role of biotic interactions and environmental change for ecosystem functions and resilience in the Baltic Sea

    Author : Åsa Austin; Johan S. Eklöf; Joakim P. Hansen; Serena Donadi; Matthew E. S. Bracken; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; biodiversity; ecosystem functions; ecosystem multifunctionality; water clarity; fish recruitment; functional traits; feedbacks; biotic interactions; competition; facilitation; foundation species; seagrass; macrophytes; lagoons; brackish water; Baltic Sea; marin ekologi; Marine Ecology;

    Abstract : Coastal ecosystems are among the most productive on Earth but subjected to many human pressures. In shallow coastal areas, aquatic vegetation constitutes foundation species that sustain secondary production and act as a nutrient filter, which may buffer human impacts. READ MORE

  4. 4. Changes in plant community diversity and management effects in semi-natural meadows in southern Sweden

    Author : Anna-Carin Linusson; Biologiska institutionen; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Plant ecology; Vegetation; Species diversity; Management intensity; Community diversity; Ordination; Växtekologi;

    Abstract : The objectives of this thesis were to: 1) survey the vegetation in semi-natural meadows in south-central Sweden, 2) discern meadow vegetation changes in eight semi-permanent plots between studies performed in the 1960s and in 1990, 3) experimentally investigate the effects of variations in management intensity in one dry and one mesic meadow, 4) experimentally investigate the effects of different management practices or absence of management on species dynamics in meadow vegetation. 1. READ MORE

  5. 5. More Water, Less Grass? : An assessment of resource degradation and stakeholders’ perceptions of environmental change in Ombuga Grassland, Northern Namibia

    Author : Patrik Klintenberg; Carl Christiansson; Wolter Arnberg; Peter Schlyter; Stein W. Bie; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Environmental monitoring; semi-arid; pastoralism; rural water supply; indicators; local knowledge; vegetation survey; satellite remote sensing; Physical geography; Naturgeografi; geografi med naturgeografisk inriktning; Physical Geography;

    Abstract : The objectives of this thesis are to assess: to what degree have natural resources deteriorated in a grazing area in northern Namibia, how do perceptions of environmental change held by local stakeholders there, correspond to scientific assessments, and how do these relate to national estimates? Analysis of the process of developing national indicators for monitoring of land degradation concluded that specific indicators should be developed on national level, and in some instances even on local level as there are no universal causes of land degradation. According to farmers overgrazing and low rainfall since the early 1990s cause negative environmental changes in the study area, partly confirming findings from national monitoring. READ MORE