Sökning: "Åldersstruktur"

Visar resultat 1 - 5 av 6 avhandlingar innehållade ordet Åldersstruktur.

  1. 1. Old-Growth Forests in the High Coast Region in Sweden and Active Management in Forest Set-Asides

    Författare :Jennie Sandström; Bengt-Gunnar Jonsson; Mattias Edman; Mikael Ohlson; Mittuniversitetet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Coarse woody debris; Dead wood; Dendrochronology; Fire history; Forest conservation; Forest structure; Log; Meta-analysis; Pine heath forest; Prescribed burning; Saproxylic fungi; Saproxylic beetles; Snag; Wood-inhabiting fungi; Aktiv skötselmetod; Bevarandebiologi; Brandhistorik; Dendrokronologi; Död ved; Hällmarkstallskog; Lågproduktiv skog; Meta-analys; Naturvård; Naturvårdsbrand; Skogsstruktur; Solbelyst död ved; Stock; Torraka; Vedlevande svamp; Vedlevande insekter; Åldersstruktur;

    Sammanfattning : In today´s intensively managed landscape, very few forests with old-growth characteristics and little human impact exist. One of the rare exceptions is pine forests on rocky soils, a forest type which has probably escaped extensive human use because of its low productivity. LÄS MER

  3. 2. Hushållens sparande : beteendevetenskapliga mätningar av hushållens sparbeteende

    Författare :Erik Lindqvist; Handelshögskolan i Stockholm; []
    Nyckelord :SAMHÄLLSVETENSKAP; SOCIAL SCIENCES;

    Sammanfattning : Hushållens fördelning av inkomsten på sparande och konsumtion har en direkt inverkan på möjligheterna att uppnå olika samhällsekonomiska målsättningar. Våra kunskaper om de faktorer som styr hushållens sparbeteende har tyvärr varit både ofullständiga och osystematiska. LÄS MER

  4. 3. Bifurcations and Exchange of Stability with Density Dependence in a Coinfection Model and an Age-structured Population Model

    Författare :Jonathan Andersson; Vladimir Kozlov; Uno Wennergren; Ezio Venturino; Linköpings universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : In nature many pathogens and in particular strains of pathogens with negative effects on species coexists. This is for simplicity often ignored in many epidemiological models. It is however still of interest to get a deeper understanding how this coexistence affects the dynamics of the disease. LÄS MER

  5. 4. Determination of stellar ages and star formation histories - a Bayesian approach With an application to nearby F and G stars

    Författare :Bjarne Rosenkilde Jørgensen; Astronomi - Genomgår omorganisation; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Astronomi; Astronomy; Galaxy evolution; Statistical methods; Stellar evolution; Data analysis;

    Sammanfattning : In order to understand the formation and evolution of the Galaxy it is imperative to know when different components formed. This means at the most basic level that we need to know the ages of stars. The present work demonstrates the many problems inherent in determining the ages of stars through comparison with stellar evolutionary models. LÄS MER

  7. 5. Development of cardiovascular disease risk in middle-aged men. The Cardiovascular Risk Factor Study in Southern Sweden, CRISS

    Författare :Karin Henriksson; Avdelningen för arbets- och miljömedicin; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Cardiovascular system; Kardiovaskulära systemet; Population Study; Overweight; S-Cholesterol; Middle-aged men; Hypertension; Ethnicity; Epidemiology; Education; Cardiovascular disease; Body height; BMI; Alcohol; Blood pressure; Unemployment;

    Sammanfattning : The Cardiovascular Risk Factor Study in Southern Sweden, CRISS, was initiated to explore if men at increased risk at developing CVD risk factors can be identified already before age 40. Starting in 1990 two birth cohorts of men residing in Helsingborg, Sweden, were surveyed at age 37 (n=991, participation rate 68%), at age 40 (n=770) and age 43 (n=702), respectively. LÄS MER