Insights into the Microbial and Viral Dynamics of a Coastal Downwelling-Upwelling Transition.
Although previous studies have described opposing states in upwelling regions, i.e., the rise of cold nutrient-rich waters and prevalence of surface warm nutrient-poor waters, few have addressed the transition from one state to the other. This study aimed to describe the microbial and viral structure during this transition and was able to obtain the taxonomic and metabolic compositions as well as physical-chemical data. This integrated approach allowed for a better understanding of the dynamics of the downwelling upwelling transition, suggesting that a wealth of metabolic processes and ecological interactions are occurring in the minute fractions of the plankton (femto, pico, nano). These processes and interactions included evidence of microbial predominance during downwelling (with nitrogen recycling and aerobic anoxygenic photosynthesis), different viral predation pressures over primary production in different states (cyanobacteria vs eukaryotes), and a predominance of diatoms and selected bacterial and archaeal groups during upwelling (with the occurrence of a wealth of nitrogen metabolism involving ammonia). Thus, the results provided insights into which microbes, viruses and microbial-mediated processes are probably important in the functioning of upwelling systems.
Departamento de Ciências do Mar, UNIFESP Baixada Santista. Santos, SP, Brazil; Instituto de Biologia, Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ, Brazil.
Gustavo Bueno
GB
Gregoracci
Instituto de Biologia, Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ, Brazil.
Ana Carolina Dos Santos
AC
Soares
Instituto de Biologia, Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ, Brazil; Laboratório de Vírus Respiratórios e do Sarampo, Instituto Oswaldo Cruz (IOC)-FIOCRUZ, Rio de Janeiro, RJ, Brazil.
Milene Dias
MD
Miranda
Instituto de Estudos do Mar Almirante Paulo Moreira (IEAPM), Arraial do Cabo, RJ, Brazil.
Ricardo
R
Coutinho
Instituto de Biologia, Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ, Brazil; Laboratório de Sistemas Avançados de Gestão de Produção-SAGE-COPPE, Centro de Gestão Tecnológica-CT2, UFRJ, Rio de Janeiro, RJ, Brazil.
Fabiano L
FL
Thompson
D001419:Bacteria / Q000235:genetics / Q000302:isolation & purification; D017753:Ecosystem; D005618:Fresh Water / Q000382:microbiology; D012623:Seawater / Q000382:microbiology; D014780:Viruses / Q000235:genetics / Q000302:isolation & purification; D014871:Water Microbiology