Search for dissertations about: "summer annual"

Showing result 1 - 5 of 84 swedish dissertations containing the words summer annual.

  2. 1. Seed dormancy and germination in an ecological context : comparative studies of annual weeds

    Author : Laila Karlsson; Per Milberg; Ken Thompson; Linköpings universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Asteraceae; Bidens; Compositae; deadnettle; Galinsoga; germination timing; Guizotia; evolution; Labiatae; Lamiaceae; Lamium; morphophysiological dormancy; Papaveraceae; Papaver; Parthenium; physiological dormancy; poppy; summer annual; Tagetes; Verbesina; winter annual; Biology; Biologi;

    Abstract : Germination ecology studies, i.e. studies of interactions between characteristics of the seeds and environmental circumstances, provide understanding of spatial and temporal patterns of emergence of wild species, as weeds in the field. A large number of species have seed dormancy, i. READ MORE

  4. 2. Migratory behaviour of Baltic salmon (Salmo salar L.) : adaptive significance of annual cycles

    Author : Torleif Eriksson; Lars-Ove Eriksson; Kees Groot; Umeå universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Migratory behaviour; annual cycles; Baltic salmon; Salmo salar; annual time program; swimming behaviour; mortality; maturity; life history;

    Abstract : This thesis evaluates the adaptive significance of annual cycles on the migratory behaviour of Baltic salmon (Salmo salar L.). The studies have included field experiments as well as laboratory studies gf maturity and migratory behaviour patterns of smolts and postsmolts mainly from the Angerman river population. READ MORE

  5. 3. Tree-rings and climate - Standardization, proxy-development, and Fennoscandian summer temperature history

    Author : Jesper Björklund; Göteborgs universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Tree rings; Fennoscandia; summer temperature; maximum latewood density MXD ; blue intensity BI ; standardization;

    Abstract : Instrumental meteorological observation are too short for trying to estimate climate change and variability on multi-decadal and centennial time-scales, and when trying to evaluate the response of the climate system to human influence, such as raised concentrations of green house gases (GHG), altered land-use, black carbon etc. To access information about the climate system predating instrumental observations, reliable proxy records (natural archives) are necessary. READ MORE

  6. 4. Inter-annual variability of rainfall in Central America : Connection with global and regional climate modulators

    Author : Tito Maldonado; Björn Claremar; Eric J. Alfaro; Jorge A. Amador; Michael Taylor; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Precipitation; climate variability; El Niño Southern Oscillation; Tropical North Atlantic; Canonical Correlation Analysis; EC-EARTH; Caribbean Low-Level Jet;

    Abstract : Central America is a region regularly affected by natural disasters, with most of them having a hydro-meteorological origin. Therefore, the understanding of annual changes of precipitation upon the region is relevant for planning and mitigation of natural disasters. READ MORE

  7. 5. Impacts of climate change on surface hydrology in the source region of the Yellow River

    Author : Feifei Yuan; Avdelningen för Teknisk vattenresurslära; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Source region of the Yellow River; climate change; summer precipitation; ENSO; teleconnection pattern; sea surface temperature; Xinanjiang model; Rainfall-Runoff process;

    Abstract : The source region of the Yellow River contributes about 35% of the total water yield in the Yellow River basin playing an important role for meeting the downstream water resources requirements. The declining water availability caused by climate change in the source region of the Yellow River is expected to have severe repercussions for the 110 million basin inhabitants in terms of water resources affecting agricultural productivity, municipal, and industrial water supply. READ MORE