title: Living in a coastal lagoon environment: photosynthetic and biochemical mechanisms of key marine macroalgae.
abstract: The physiological status of Cystoseira compressa, Padina pavonica and Palisada tenerrima was studied by in vivo chlorophyll fluorescence, pigment content, stoichiometry (C:N), accumulation of UV photoprotectors and antioxidant activity; comparing their photosynthetic response in a coastal lagoon (Mar Menor) and in Mediterranean coastal waters. In general, the specimens reached their highest ETRmax in spring in the Lagoon, but in summer in the Mediterranean, coinciding with their maximum biomass peak. The species exhibited a dynamic photoinhibition. Except C. compressa, they showed a lower decrease in Fv/Fm and higher recovery rates in the Mediterranean populations when exposed to high irradiance. The higher salinity and temperature of the lagoon could impair the photoprotection mechanisms. The acclimation to lagoon environments is species-specific and involves complex regulatory mechanisms. The results underline the importance of N in repair, avoidance, quenching and scavenging mechanisms. In general, Lagoon specimens showed higher pigment concentration. Although xanthophylls play important photo-protective and antioxidant roles, the observed trend is more likely to be explained by the higher temperatures reached in the lagoon compared to Mediterranean. Therefore the studied photosynthetic and biochemical mechanisms can be effective not only for high irradiance, but also for higher temperatures in a climate change scenario, but are highly dependent on nutrient availability.
authors.affiliation: Departamento de Ecología e Hidrología, Facultad de Biología, Campus de Espinardo, Regional Campus of International Excellence "Campus Mare Nostrum", Universidad de Murcia, Murcia 30100, Spain. Electronic address: martagarcia@um.es.
authors.forename: Marta
authors.initials: M
authors.lastname: García-Sánchez
authors.affiliation: Departamento de Ecología y Geología, Facultad de Ciencias, Universidad de Málaga, Málaga 29071, Spain.
authors.forename: Nathalie
authors.initials: N
authors.lastname: Korbee
authors.affiliation: Departamento de Biología Vegetal I, Facultad de Biología, Universidad Complutense de Madrid, Madrid 28040, Spain.
authors.forename: Isabel María
authors.initials: IM
authors.lastname: Pérez-Ruzafa
authors.affiliation: Departamento de Ecología e Hidrología, Facultad de Biología, Campus de Espinardo, Regional Campus of International Excellence "Campus Mare Nostrum", Universidad de Murcia, Murcia 30100, Spain.
authors.forename: Concepción
authors.initials: C
authors.lastname: Marcos
authors.affiliation: Departamento de Ecología y Geología, Facultad de Ciencias, Universidad de Málaga, Málaga 29071, Spain.
authors.forename: Félix L
authors.initials: FL
authors.lastname: Figueroa
authors.affiliation: Departamento de Ecología e Hidrología, Facultad de Biología, Campus de Espinardo, Regional Campus of International Excellence "Campus Mare Nostrum", Universidad de Murcia, Murcia 30100, Spain.
authors.forename: Ángel
authors.initials: Á
authors.lastname: Pérez-Ruzafa
mesh_terms: D000064:Acclimatization; D000975:Antioxidants / Q000378:metabolism; D002244:Carbon / Q000378:metabolism; D002734:Chlorophyll / Q000378:metabolism*; D017753:Ecosystem; D019083:Mediterranean Region; D009584:Nitrogen / Q000378:metabolism; D010788:Photosynthesis; D011157:Population Dynamics; D012623:Seawater / Q000737:chemistry; D012624:Seaweed / Q000378:metabolism* / Q000502:physiology
chemical_list: D000975:Antioxidants; D002734:Chlorophyll; D002244:Carbon; D009584:Nitrogen
keywords: Acclimation; Chlorophyll fluorescence; Coastal lagoon; Ecophysiology; Macroalgae; Photosynthesis