Global warming-induced temperature effects to intertidal tropical and temperate meiobenthic communities

Global climate change and the related temperature rise strongly impact marine life and have long been in the center of scientific attention. This experimental work investigates thermal-stress effects on intertidal meiofauna from tropical and temperate coasts, focusing on community responses. Natural communities were exposed for a month to ambient, elevated constant temperatures and diurnal fluctuating temperature regimes with elevated peak maxima, to mimic realistic future climate conditions. Abundance, biodiversity, community composition and functional diversity were assessed. Differential responses between a tropical and a temperate community were revealed. The tropical nematode assemblage was more tolerant to the elevated constant than to the fluctuating temperature regime, whereas the temperate assemblage was equally affected by both. Shifts in dominance of temperature-tolerant species in elevated constant and fluctuating temperature treatments (due to temperature variations) were observed and explained by a combination of differential tolerances and shifts in species interactions. Overall, global warming-induced temperature was found to alter species dynamics within meiobenthic communities, which may have further implications for the ecosystem.