Izšķīdušo organisko vielu bioloģiskā izmantojamība bakterioplanktona un fitoplanktona klātbūtnē Rīgas līcī
Loading...
Date
Authors
Advisor
Journal Title
Journal ISSN
Volume Title
Publisher
Latvijas Universitāte
Language
N/A
Abstract
Izškidušo organisko vielu biologiska izmantojamiba
bakterioplanktona un fitoplanktona klatbutne Rigas lici
Upju izškidušas organiskas vielas (DOM) nepartraukti papildina iesalo udenu ekosistemas,
veicinot to produktivitati. Masveida savairošanos Baltijas jura vasaras izraisa galvenokart slapekli
fiksejošas cianobakterijas, bet Rigas lica piekraste ari Microcystis aeruginosa. Promocijas darba ir
noskaidrota ar huminvielam bagatas alohtonas DOM biologiska izmantojamiba un ietekme uz
iesalu udenu bakterioplanktona - fitoplanktona sabiedribam. Upju ienesta DOM tiek paklauta
mikrobialai degradacijai jau piekrastes rajonos, bet atklatos udenos bakterioplanktons izmanto
autohtonas organiskas vielas. Ar cianobakterijam asocietas heterotrofas bakterijas mineralize
alohtono DOM, atbrivojot vienkaršus, viegli izmantojamus slapekla savienojumus (nitratus,
nitritus un amoniju), nodrošinot M. aeruginosa ar viegli izmantojamiem slapekla savienojumiem.
Atslegas vardi: heterotrofas bakterijas, Microcystis aeruginosa, DOM, DON, Rigas licis
Biological use of dissolved organic matter by bacterioplankton and phytoplankton in the Gulf of Riga River brought dissolved organic matter (DOM) continuously supplements coastal ecosystems, contributing to the productivity increase. Massive proliferation of phytoplankton in the Baltic Sea in summers is mainly caused by nitrogen-fixing cyanobacteria, but in coastal areas of the Riga Gulf also by Microcystis aeruginosa. In dissertation is studied the contribution of brackish heterotrophic bacteria in biodegradation of humic rich DOM and its effect on development of phytoplankton and bacterioplankton communities. Riverine DOM is exposed to microbial mineralization already in coastal areas but in open waters bacterioplankton use autochthonous organic matter. Bacteria associated with M. aeruginosa consume riverine DOM and join ammonification and nitrification process, supplying cyanobacteria with simple nitrogen compounds. Kay words: heterotrophic bacteria, Microcystis aeruginosa, DOM, DON, the Gulf of Riga
Biological use of dissolved organic matter by bacterioplankton and phytoplankton in the Gulf of Riga River brought dissolved organic matter (DOM) continuously supplements coastal ecosystems, contributing to the productivity increase. Massive proliferation of phytoplankton in the Baltic Sea in summers is mainly caused by nitrogen-fixing cyanobacteria, but in coastal areas of the Riga Gulf also by Microcystis aeruginosa. In dissertation is studied the contribution of brackish heterotrophic bacteria in biodegradation of humic rich DOM and its effect on development of phytoplankton and bacterioplankton communities. Riverine DOM is exposed to microbial mineralization already in coastal areas but in open waters bacterioplankton use autochthonous organic matter. Bacteria associated with M. aeruginosa consume riverine DOM and join ammonification and nitrification process, supplying cyanobacteria with simple nitrogen compounds. Kay words: heterotrophic bacteria, Microcystis aeruginosa, DOM, DON, the Gulf of Riga