Mudanças climáticas e comunidades entremarés de costões rochosos – efeitos da temperatura e hidrodinamismo

Abstract

The intertidalbenthiccommunities that inhabit rocky shores are subject to wave action and tidal variations,being exposed to the air during low tides and quite susceptible to climate change effects ‘cause among the expected consequences are the increase in the frequency of storms that increase hydrodynamicsand terrestrial heat waves. The experimental increase in air temperature in granite platesgenerated by the presence of black, white and borderless edges, installed in the Tetraclitastalactiferafringe was investigated. Simultaneously, it was evaluated how different degrees of wave impact can affect sessile macrobenthic communities, based on monitoring on two shores less and more exposed to wave action, in ItaipuandPiratininga respectively, in Niterói- Rio de Janeiro. This experiment was conducted between March 2022 and February 2023. Green algae grew more on the wave-exposed shore, where mussels were also found; while barnacles developed faster in a calmer environment. Few or no organism remained on plates that showed higher temperatures (up to 52.9°C) throughout monitoring. The less exposed shore also has a more heterogeneous habitat and the plate communities were more different among themselves than on the more exposed shore. The black plates warmer the substrate plate and, at the end of the sampling period, they contained smallest number of barnacles, especially in Piratininga. The combined effects of increased air temperature and wave action seem more harmful to communities than when analyzed separately.However,the impacts on each species are different, and it’s necessary to understand how each one responds to these effects.