Search results for "TROPHIC TRANSFER"
showing 4 items of 4 documents
Lake restoration influences nutritional quality of algae and consequently Daphnia biomass
2020
AbstractFood quality is one of the key factors influencing zooplankton population dynamics. Eutrophication drives phytoplankton communities toward the dominance of cyanobacteria, which means a decrease in the availability of sterols and long-chain polyunsaturated fatty acids (EPA and DHA). The effects of different restoration measures on the nutritional quality of the phytoplankton community and subsequent impacts on zooplankton biomass have rarely been considered. We analyzed the nutritional quality of phytoplankton in the eutrophic Lake Vesijärvi in southern Finland over a 37-year period, and studied the impacts of two restoration measures, biomanipulation and hypolimnetic aeration, on th…
Structural and functional organization of fish assemblages in a Mediterranean shallow CO2 vent.
2017
Gli effetti dell’acidificazione degli oceani a livello globale hanno richiamato l’attenzione degli scienziati su dei sistemi marini naturali quali i vent superficiali di CO₂. Si tratta di mesocosmi naturali, in quanto su piccole scale spaziali (anche di pochi metri) si osservano marcati gradienti di pH, dove poter testare ipotesi ecologiche dell’acidificazione delle acque marine. Obiettivo della tesi è studiare le risposte della popolazione ittica alla riduzione del pH in vent superficiali mediterranei utilizzando numerosi descrittori, quali la struttura di comunità, l’organizzazione trofica, le caratteristiche e la composizione chimica delle strutture carbonatiche. Inoltre poiché i vent so…
Patterns and dynamics of neutral lipid fatty acids in ants – implications for ecological studies
2017
Background Trophic interactions are a fundamental aspect of ecosystem functioning, but often difficult to observe directly. Several indirect techniques, such as fatty acid analysis, were developed to assess these interactions. Fatty acid profiles may indicate dietary differences, while individual fatty acids can be used as biomarkers. Ants are among the most important terrestrial animal groups, but little is known about their lipid metabolism, and no study so far used fatty acids to study their trophic ecology. We set up a feeding experiment with high- and low-fat food to elucidate patterns and dynamics of neutral lipid fatty acids (NLFAs) assimilation in ants. We asked whether dietary fatt…