Studies on chemical, physical and biological conditions in Swedish rockpool ecosystems

Abstract

Abstract Although rockpools are highly dynamic and changing systems which cannot be strictly classified, it has been found convenient to recognize five main types: permanent salt-water pools, ephemeral salt-water pools, brackish-water pools, permanent freshwater pools and ephemeral freshwater pools. The physical and chemical conditions of the rockpools are very variable. Salinity, temperature, oxygen and pH have especially been considered in this investigation. These parameters are not only regulated by the ambient conditions of the climate and the sea water, but also by such biological conditions as population density and algal growth, which particularly control oxygen and pH conditions. The salinity has formerly been considered to be the main regulating parameter in rockpools, but along the Baltic coast salinity fluctuations are mostly moderate in large and medium-sized pools. In these pools the temperature is considered to be of greatest importance for the rockpool organisms; diel fluctuations of 10°C,...