In arid zones, ephemeral rock pools exhibit cyclical and unpredictable hydroperiods, which entail long periods of drought and short periods of flooding. The hydrological perturbations associated with the dry phase could potentially trigger abrupt changes in the structure and dynamics of the communities in temporary ecosystems. Our main objective was to investigate the processes shaping phytoplankton communities, driven by local environmental variables, spatial distribution (urban and protected rock pools), and the hydrological regime (different phases), with a focus on disturbances over space and time. The hydrological regime was irregular throughout most months, characterized by three phases distributed in rainy and dry periods. Phytoplankton biomass was higher in urban rock pools in the dry period, and analyses indicated that community structure was influenced by the local variables as temperature and total dissolved solids, by temporal phases and by spatial factors. Replacement contributed more to overall community dissimilarity than nestedness. Overall, the results highlight the role of environmental fluctuations and human pressure in urban rock pools, in structuring phytoplankton communities.

在干旱地区，短暂的岩石池表现出周期性和不可预测的水文周期，这会导致长期干旱和短期洪水。与干旱阶段相关的水文扰动可能会引发临时生态系统中群落结构和动态的突然变化。我们的主要目标是研究由当地环境变量、空间分布（城市和受保护的岩石池）和水文状况（不同阶段）驱动的浮游植物群落形成过程，重点关注空间和时间上的干扰。大部分月份水文情势不规律，表现为雨季和旱季三个阶段。在干旱时期，城市岩石池中的浮游植物生物量较高，分析表明群落结构受到温度和总溶解固体等局部变量、时间阶段和空间因素的影响。替换对整体群落差异的影响比嵌套更大。总体而言，结果强调了城市岩石池中环境波动和人类压力在构建浮游植物群落中的作用。