FN Archimer Export Format
PT J
TI High nutrient loading and climatic parameters influence the dominance and dissimilarity of toxigenic cyanobacteria in northern bays of Lake Victoria
BT 
AF Olokotum, Mark
   Troussellier, Marc
   Escalas, Arthur
   Hamlaoui, Sahima
   Okello, William
   Semyalo, Ronald
   Humbert, Jean-François
   Bernard, Cecile
AS 1:1,2;2:3;3:3;4:4;5:2;6:1;7:5;8:4;
FF 1:;2:;3:;4:;5:;6:;7:;8:;
C1 Department of Zoology, Entomology and Fisheries Sciences, Makerere University, Kampala, Uganda
   National Fisheries Resources Research Institute (NaFIRRI), Jinja, Uganda
   MARBEC, CNRS-Univ Montpellier-IFREMER-IRD, Montpellier, France
   UMR 7245 Molécules de Communication et Adaptations des Microorganismes (MCAM), CNRS-MNHN, Muséum National d’Histoire Naturelle, Paris, France
   INRAE-Institute of Ecology and Environmental Sciences of Paris (iEES), Sorbonne University, Paris, France
C2 UNIV MAKERERE, UGANDA
   NAFIRRI, UGANDA
   CNRS, FRANCE
   MNHN, FRANCE
   INRAE, FRANCE
UM MARBEC
IN WOS Cotutelle UMR
   copubli-france
   copubli-int-hors-europe
   copubli-sud
IF 3.032
TC 4
UR https://archimer.ifremer.fr/doc/00695/80753/84039.pdf
   https://archimer.ifremer.fr/doc/00695/80753/84041.docx
LA English
DT Article
DE ;Eutrophication;Lake Victoria;Cyanobacteria;Phytoplankton;Diversity;Bays and gulfs
AB Eutrophication of Lake Victoria led to changes in its phytoplankton communities. However, different levels of eutrophication exist in the open lake and the bays, and between embayments. This study utilized spatial and temporal sampling of Napoleon Gulf and Murchison Bay, exhibiting different trophic conditions. Over one year, we investigated phytoplankton biomass, richness, diversity and dissimilarity, and related the dynamics of the dominant species to the limnological and climatic conditions. The results confirmed that Napoleon Gulf and Murchison Bay showed large differences in eutrophication status, with lower nutrient concentrations in Napoleon Gulf than in Murchison Bay, where a strong gradient was observed from inshore to offshore areas. These nutrient dynamics resulted in a 4 to 10 fold higher chlorophyll-a in Murchison Bay than in Napoleon Gulf. From the embayments, 135 phytoplankton taxa were recorded with no significant differences in alpha diversity. However, high dissimilarity in community structure was observed in beta diversity, mostly due to a turnover among the dominant toxigenic species. Thus, from a similar species pool, there was a shift in the dominant toxigenic cyanobacteria from Microcystis flos-aquae and M. aeruginosa in Murchison Bay, Dolichospermum circinale and Planktolyngbya circumcreta in Napoleon Gulf to D. circinale in the offshore stations. These cyanobacteria are toxigenic taxa with known health hazards. Using partial least square models, we showed that both climatic variables (e.g. wind, solar radiation) and levels of inorganic dissolved nutrients (e.g. SRP, NO3–, and NH4+) are the main drivers of differences and dominance in cyanobacteria communities in northern Lake Victoria. 
PY 2021
PD AUG
SO Journal Of Great Lakes Research
SN 0380-1330
PU Elsevier BV
VL 47
IS 4
UT 000670214400004
BP 985
EP 996
DI 10.1016/j.jglr.2021.04.021
ID 80753
ER

EF