SAME SPECIES, DIFFERENT POPULATION DYNAMICS: SPATIO-TEMPORAL DIFFERENCES OF Undaria pinnatifida (OCHROPHYTA, PHAEOPHYCEAE) IN THE INTERTIDAL OF NORTH PATAGONIA, ARGENTINA

ARCÁNGEL ANDREA EVANGELINA; RODRÍGUEZ EMILIANO ALEXIS; SAAD JUAN FRANCISCO; DE LA BARRA PAULA; NARVARTE MAITE; STORERO LORENA PÍA; PEREYRA PATRICIO JAVIER

Journal of Phycology

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2023

Population dynamics can be influenced by physical and biological factors, particularly in stressful environments. Introduced species usually have great physiological plasticity, resulting in populations with different traits. Undaria pinnatifida (hereafter Undaria), a macroalga originally described for northeast Asia, was introduced in northern Patagonia, Argentina (San Matías Gulf) near 2010. To describe the spatio-temporal variability in population structure and morphometry of Undaria, we conducted monthly field samplings for two years at the intertidal area of two contrasting sites in the San Matías Gulf. Individuals of Undaria were classified by developmental stage, and their morpho-gravimetric variables were measured. In both intertidal sites: juveniles were found in higher proportion during austral autumn, they grew and matured during autumn-winter months (from May onwards), and individuals senesced during early austral summer (December and January). Conversely, density and biomass were largely different between sites, and individuals showed slight morphological variability between sites. Environmental (e.g. nutrient concentration, available substrate) and biological factors (e.g. facilitation, competition) may explain the observed differences. Since there is not a macroalga with Undaria morphometrical characteristics in the intertidal environments of San Matías Gulf, studying this recent introduction gives us a better understanding of its potential ecological effects.