Climate change affects key nitrogen-fixing bacterial populations on coral reefs.
Coral reefs are at serious risk due to events associated with global climate change. Elevated ocean temperatures have unpredictable consequences for the ocean's biogeochemical cycles. The nitrogen cycle is driven by complex microbial transformations, including nitrogen fixation. This study investigated the effects of increased seawater temperature on bacteria able to fix nitrogen (diazotrophs) that live in association with the mussid coral Mussismilia harttii. Consistent increases in diazotroph abundances and diversities were found at increased temperatures. Moreover, gradual shifts in the dominance of particular diazotroph populations occurred as temperature increased, indicating a potential future scenario of climate change. The temperature-sensitive diazotrophs may provide useful bioindicators of the effects of thermal stress on coral reef health, allowing the impact of thermal anomalies to be monitored. In addition, our findings support the development of research on different strategies to improve the fitness of corals during events of thermal stress, such as augmentation with specific diazotrophs.
1] LEMM, Laboratory of Molecular Microbial Ecology, Institute of Microbiology Paulo de Góes, Federal University of Rio de Janeiro (UFRJ), Rio de Janeiro, Brazil [2] Department of Microbial Ecology, Centre for Ecological and Evolutionary Studies, University of Groningen, Groningen, The Netherlands.
Henrique F
HF
Santos
LEMM, Laboratory of Molecular Microbial Ecology, Institute of Microbiology Paulo de Góes, Federal University of Rio de Janeiro (UFRJ), Rio de Janeiro, Brazil.
Flávia L
FL
Carmo
National Museum, UFRJ, Rio de Janeiro, Brazil.
Gustavo
G
Duarte
Department of Microbial Ecology, Centre for Ecological and Evolutionary Studies, University of Groningen, Groningen, The Netherlands.
Francisco
F
Dini-Andreote
1] National Museum, UFRJ, Rio de Janeiro, Brazil [2] Coral Vivo Institute, Rio de Janeiro, Brazil.
Clovis B
CB
Castro
1] LEMM, Laboratory of Molecular Microbial Ecology, Institute of Microbiology Paulo de Góes, Federal University of Rio de Janeiro (UFRJ), Rio de Janeiro, Brazil [2] Coral Vivo Institute, Rio de Janeiro, Brazil.
Alexandre S
AS
Rosado
Department of Microbial Ecology, Centre for Ecological and Evolutionary Studies, University of Groningen, Groningen, The Netherlands.
Jan Dirk
JD
van Elsas
1] LEMM, Laboratory of Molecular Microbial Ecology, Institute of Microbiology Paulo de Góes, Federal University of Rio de Janeiro (UFRJ), Rio de Janeiro, Brazil [2] Coral Vivo Institute, Rio de Janeiro, Brazil.
Raquel S
RS
Peixoto
D000818:Animals; D037421:Anthozoa / Q000382:microbiology*; D001419:Bacteria / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D057231:Climate Change; D057894:Coral Reefs; D008969:Molecular Sequence Data; D009586:Nitrogen Fixation / Q000235:genetics; D010088:Oxidoreductases / Q000235:genetics; D012623:Seawater; D013696:Temperature
D010088:Oxidoreductases; C029130:nitrogenase reductase