Sökning: "richness"

Visar resultat 1 - 5 av 256 avhandlingar innehållade ordet richness.

  1. 1. Factors influencing the biogeography of bacteria in fresh waters - a metacommunity approach

    Författare :Jürg Brendan Logue; Eva S. Lindström; Silke Langenheder; Lars Tranvik; Byron Crump; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; bacteria; diversity; richness; community composition; dispersal; metacommunity; fresh water; biogeography; Freshwater ecology; Limnisk ekologi; Microbiology; Mikrobiologi; Biologi med inriktning mot limnologi; Biology with specialization in Limnology;

    Sammanfattning : One of ecology’s primary goals is to comprehend biodiversity and its patterns of distribution over space and time. Since microorganisms play a pivotal role in key ecological processes, the diversity of microbial communities may have important implications for the stability and functioning of Earth’s ecosystems. LÄS MER

  3. 2. Development and dynamics of the normal gut microbiota

    Författare :Lisa M. Olsson; Göteborgs universitet; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; dynamics; ecology; gut microbiome; gut microbiota development; microbiota; richness; Prader-Willi Syndrome; stability; variation;

    Sammanfattning : Altered gut microbiota configurations have been linked to human diseases. To identify mechanistic links between altered gut microbiota and disease states, definitions of the healthy gut microbiota need to be established. LÄS MER

  4. 3. Soil phosphorus – a multidimensional resource that plays an important role for grassland plant species richness

    Författare :Jakob Sandberg; Biologiska institutionen; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; niche dimension; nutrient limitation; niche differentiation; competition; soil nitrogen; soil phosphorus; plant diversity; species richness; Grassland; land use; landscape scale;

    Sammanfattning : The semi-natural grassland habitats contain an important part of the plant diversity in Europe. Changes in farming practices have lead to drastic decreases in plant species richness. The aim of the present thesis is to contribute to the knowledge about mechanisms governing the plant species richness in grasslands with emphasis on soil nutrients. LÄS MER

  5. 4. Investigations of species richness effects on ecosystem functioning using stream-living macroinvertebrates as model organisms

    Författare :Micael Jonsson; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Ecology; Species richness; species loss; process rates; ecosystem function; streams; macroinvertebrates; Ekologi; Terrestrial; freshwater and marine ecology; Terrestisk; limnisk och marin ekologi;

    Sammanfattning : The work in this thesis deals with effects of changed species richness on process rates among stream-living macroinvertebrates. Global biodiversity is decreasing rapidly and it is poorly known what the consequences of this loss may be for ecosystems and the services they provide. LÄS MER

  7. 5. Riqueza léxica y expresión escrita en aprendices suecos de ELE : Proficiencia general, competencia léxica pasiva, tipo y complejidad de la tarea

    Författare :Marco Berton; María Bernal; Laura Sánchez Pérez; Folkert Kuiken; Stockholms universitet; []
    Nyckelord :SAMHÄLLSVETENSKAP; SOCIAL SCIENCES; HUMANIORA; HUMANITIES; lexical richness; foreign language writing; Spanish; linguistic complexity; TBLT; task-based; task complexity; vocabulary; second language acquisition; riqueza léxica; ELE; producción escrita; complejidad lingüística; enfoque por tareas; complejidad de la tarea; vocabulario; adquisición de segundas lenguas; romanska språk med inriktning mot spanska; Romance Languages; Specialisation in Spanish;

    Sammanfattning : The present study explored lexical richness in the written production of Swedish university students of Spanish as a foreign language. Two aspects of lexical richness were investigated in the study, i.e., diversity (the ability to use a varied lexical repertoire), and sophistication (the proportion of relatively infrequent words). LÄS MER