Browsing by Author "Vasconcelos, Rita P."
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- Contrasting patterns of energy metabolism in northern vs southern peripheral European flounder populations exposed to temperature rising and hypoxiaPublication . Pédron, Nicolas; Le Du, Jessy; Charrier, Grégory; Zambonino-Infante, José-Luis; Le Bayon, Nicolas; Vasconcelos, Rita P.; Fonseca, Vanessa F.; Le Grand, Fabienne; Laroche, JeanA two months common garden experiment was carried out to explore the potential differences of energy metabolism in northern core (France, 50°N and 47°N) vs southern peripheral (Portugal, 41°N) populations of European flounder Platichthys flesus, submitted to cold condition (CC: water temperature = 10 °C) and to warm and hypoxic condition (WHC: water temperature = 22 °C, and moderate hypoxia with O2 saturation = 40% during the last 6 days). Convergent growth rates (in length) were observed in the different populations and conditions, when the southern peripheral population of Portugal did not grow under cold conditions. A general reduction in liver lipid storage was observed in all populations subjected to WHC when compared to CC, whereas muscle lipid storage was unaffected. The thermal and hypoxia treatment induced changes in muscle phospholipids (PL) ratios: phosphatidylserine/PL, phosphatidylinositol/PL, between northern and southern populations. Fish from northern estuaries displayed marked anaerobiosis in WHC (increased liver LDH activity) vs marked aerobiosis under CC (higher muscle CS and CCO activities). Contrariwise, fish from the southern estuary displayed equilibrium between anaerobiosis and aerobiosis activities in WHC. Flounders from the southern population exhibited generally lower G6PDH activity (proxy for anabolism and for defense against oxidative damage), tissue-specific anaerobiosis response (muscle LDH activity) and lower CS and CCO muscle activities (aerobiosis markers) when compared to northern populations. Globally, these inter-population differences in bioenergetics suggest that southern peripheral vs northern core populations have developed differential capacity to cope with interacting stressors and that much of this variation is more likely due to local adaptation.
- Functional diversity in marine fish assemblagesPublication . Henriques, Sofia; Dolbeth, Marina; Matos, Paula; Pecuchet, Laurene; Bernardo, Cristiane Palaretti; Weigel, Benjamin; McLean, Matthew; Hidalgo, Manuel; Tzanatos, Evangelos; Vasconcelos, Rita P.In the last decades, the rising interest in trait-based ecology is closely related to a growing demand for knowledge on ecosystems’ functioning and on mechanisms generating ecological patterns and processes, and with the urgency for approaches that allow to predict the consequences of climate change and anthropogenic impacts (McGill et al., 2006; De Bello et al., 2021a,b). This fundamental knowledge is difficult to obtain when considering specific species (i.e., taxonomic-based ecology), therefore ecologists are increasingly using functional diversity approaches (i.e., trait-based ecology), with the added advantage of allowing the comparison across different ecosystems and biogeographical regions, which due to biogeographical reasons support different species compositions (e.g., Henriques et al., 2017a,b). Functional diversity (FD) refers to the distribution and range of what species do (as determined by their functional traits) in a given ecosystem, influencing how the ecosystem operates or functions (e.g., stability, dynamics, productivity; Tilman, 2001; Petchey and Gaston, 2006). Currently, the most accepted definition of the trait was proposed by Violle and colleagues in which a trait is defined as “any morphological, physiological or phenological feature measurable at the individual level, from the cell to the whole organism” (Violle et al., 2007). For a trait to be considered a functional trait, it needs to influence organismal performance (fitness), meaning its growth, reproduction, and/or survival (McGill et al., 2006; Violle et al., 2007). Additionally, traits can also be related to the effect of organisms on ecosystem properties, or on the other hand, to how they respond to a disturbance or environmental change (Hooper et al., 2005). In this way, traits can be further divided into the following: (1) effect traits, those that significantly affect another trophic level (e.g., predator-prey interactions) and/or an ecosystem process (e.g., nutrient cycling, primary productivity), regardless of whether they affect or not the organismal performance; (2) response traits, those that allow organisms to survive, grow, and reproduce under different disturbances and/or environmental conditions (biotic and abiotic factors; Lavorel and Garnier, 2002).