Avancerad sökning

Visar resultat 1 - 5 av 13 avhandlingar som matchar ovanstående sökkriterier.

1. 1. Baltic Sea phytoplankton in a changing environment

   Författare :Mireia Bertos-Fortis; Catherine Legrand; Ilana Berman-Frank; Linnéuniversitetet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; phytoplankton ecology; cyanobacteria; dynamics; environmental factors; successional patterns; interactions; life strategies; non-ribosomal peptides; diversity; nodularin; N. spumigena; Akvatisk ekologi; Aquatic Ecology;

   Sammanfattning : Future climate scenarios in the Baltic Sea project increasing sea surface temperature, as well as increasing precipitation and river runoff resulting in decreased salinity. These changes can severely impact the dynamics and function of brackish water communities, specifically phytoplankton. LÄS MER

3. 2. Ecology of lichens in boreal coniferous forests with reference to spatial and temporal patterns

   Författare :Per-Anders Esseen; Lars Ericson; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Lichens; epiphytes; Alectoria; Bryoria; Cladonia; Usnea; Picea abies; Pinus sylvestris; dispersal; litterfall; succession; diversity; spatial patterns;

   Sammanfattning : The thesis deals with the ecology of lichens in two contrasting types of forest, epiphytic lichens in old Picea abies forest of the fi re-refugia type and epigeic as well as epixylic lichens in a successional sequence of fire- susceptible Pinus sylvestris forests. Results in five separate papers form the basis for a discussion of general patterns of dispersal, succession and life strategies in lichens. LÄS MER

4. 3. Interactions between natural enemies and the dioecious herb Silene dioica

   Författare :Viktoria Pettersson; Barbara E. Giles; Lars Ericson; Pia Mutikainen; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Silene dioica; Delia criniventris; Caryocolum viscariella; Microbotryum violaceum; plant-herbivore interactions; plant -pathogen interactions; sex bias; sex rato; successional gradients; fitness effects; Skeppsvik Archipelago; Terrestrial ecology; Terrestisk ekologi; ekologisk botanik; Ecological Botany;

   Sammanfattning : About 6% of all angiosperms are dioecious. This separation of sexual function to male and female individuals, and the fundamentally different patterns of reproductive resource allocation that follows that separation, are thought to have important ecological and evolutionary consequences for plant enemy interactions. LÄS MER

5. 4. Long-term studies of succession : Colonisation and seed banks

   Författare :Ulf Grandin; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Ecology; Ellenberg indicator values; genetic variation; long-term study; Lythrum salicaria; Moehringia trinervia; primary succession; seed bank; Ekologi; Terrestrial; freshwater and marine ecology; Terrestisk; limnisk och marin ekologi; ekologisk botanik; Ecological Botany;

   Sammanfattning : Using data from long-term studies of the vegetation in two areas under primary succession, patterns of colonisation and the accumulated seed bank during plant succession were studied.At century-old small islands in Lake Hjälmaren, Sweden, the genetic structure of differently old populations of Moehringia trinervia and Lythrum salicaria was studied, using allozyme variation for M. LÄS MER

7. 5. Vegetationssuccessioner - med speciell referens till Kvikkjokkdeltat

   Författare :Lars-Erik Liljelund; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Växtgeografi; Sverige; Lappland; Kvikkjokk;

   Sammanfattning : Clement's holological and Gleason's mereological approach about plant successions are. discussed. Ecological succession is here defined as a directed change of the space in time and is identified by immigration and extinction of populations. Establishment is a central process in all plant successions. LÄS MER