Interactive Effect of UVR and Phosphorus on the Coastal Phytoplankton Community of the Western Mediterranean Sea: Unravelling Eco-Physiological Mechanisms
Metadatos
Afficher la notice complèteAuteur
Carrillo Lechuga, Presentación; Medina Sánchez, Juan Manuel; Herrera, Guillermo; Durán, Cristina; Segovia García, María del Carmen; Cortés, Dolores; Salles, Soluna; Korbee, Nathalie; Figueroa, Félix L.; Mercado, Jesús M.Editorial
Plos One
Date
2015-10-29Referencia bibliográfica
Carrillo P, Medina-Sánchez JM, Herrera G, Durán C, Segovia M, Cortés D, et al. (2015) Interactive Effect of UVR and Phosphorus on the Coastal Phytoplankton Community of the Western Mediterranean Sea: Unravelling Eco-Physiological Mechanisms. PLoS ONE 10(11): e0142987. doi:10.1371/journal.pone.0142987
Patrocinador
Spanish Ministries of Science and Innovation (CGL2011-23681/BOS); Consejería de Innovación, Ciencia y Empresa – Junta de Andalucía’ (Excelencia CVI-02598); Spanish government ‘Formación de Profesorado Universitario fellowshipRésumé
Some of the most important effects of global change on coastal marine systems include
increasing nutrient inputs and higher levels of ultraviolet radiation (UVR, 280–400 nm),
which could affect primary producers, a key trophic link to the functioning of marine food
webs. However, interactive effects of both factors on the phytoplankton community have
not been assessed for the Mediterranean Sea. An in situ factorial experiment, with two levels
of ultraviolet solar radiation (UVR+PAR vs. PAR) and nutrients (control vs. P-enriched),
was performed to evaluate single and UVR×P effects on metabolic, enzymatic, stoichiometric
and structural phytoplanktonic variables. While most phytoplankton variables were not
affected by UVR, dissolved phosphatase (APAEX) and algal P content increased in the presence
of UVR, which was interpreted as an acclimation mechanism of algae to oligotrophic
marine waters. Synergistic UVR×P interactive effects were positive on photosynthetic variables
(i.e., maximal electron transport rate, ETRmax), but negative on primary production
and phytoplankton biomass because the pulse of P unmasked the inhibitory effect of UVR.
This unmasking effect might be related to greater photodamage caused by an excess of
electron flux after a P pulse (higher ETRmax) without an efficient release of carbon as the
mechanism to dissipate the reducing power of photosynthetic electron transport.