Contribution to the knowledge of ecotones: colonisation of the banks of temporary environments in Eastern Morocco

Abstract

The banks of dayas (temporary pools) is a very interesting environment, characterised by species with extremely strict ecological requirements. Contrary to riparian communities of running water, which are present throughout the year, riparian populations of temporary stagnant environments only occur during the short period of impoundment. The colonisation of these environments depends on various parameters such as rainfall, temperature, and the size and depth of the water bodies. The impoundment of dayas of Sidi Bouhria is done after autumn and spring rains, if they are sufficiently abundant, and they dry up, in all cases, during the summer. This study aims to provide an overall synthesis about the colonisation of banks of dayas by riparian beetles. The samples were taken during the complete impoundment of each daya, from its appearance, after a rainfall, to its drying up. The fauna was collected every two days during one hour of sampling. The colonisation of the banks of the temporary environments studied takes place in three phases. The first phase is dominated by species of terrestrial origin from the vicinity of the dayas, the second phase is dominated by riparian and hygrophilous species that originate from the banks of more or less distant aquatic environments, and the third phase, which occurs with the drying of the environment, marks the return of terrestrial species.