A long-term dataset on hydrology and suspended sediments in the Kamech catchment from the OMERE Observatory

The Mediterranean region is characterized by a highly variable climate marked by prolonged dry spell interspersed with intense rainfall events mainly in autumn. Understanding the dynamics of water and sediment fluxes in this climatic context is crucial for recommending effective management strategies to mitigate erosion and runoff impacts. However, high-frequency datasets for both hydrology and sediment fluxes are often lacking for small Mediterranean catchments in North Africa, thus rendering these processes poorly understood. In this context, the Kamech Critical Zone Observatory was established in 2004 to document high-frequency rainfall, discharge, and sediment fluxes across the 2.63 km2 Kamech catchment in Cape Bon, Tunisia. The landscape is characterised by hilly terrain, and the soil type is dominated by Vertisols, which crack for approximately half of the year. This catchment's land is mainly used to cultivate annual cereals and leguminous crops. The monitoring system comprises four nested hydrological stations, ranging in scale from a 1.3 ha plot to the outlet of the 263 ha catchment area. The longest time series covers almost 30 years. This article synthesizes the datasets of the observatory related to evaporation, rainfall, discharge and suspended sediment concentration. It describes the methodologies used to collect and process the data, including procedures for assessing data quality. It also suggests additional homogenized time series to facilitate subsequent hydrological analysis. Finally, it presents some preliminary explorations of the datasets and it suggests avenues for further studies. All datasets referenced in this work are openly accessible via the repository: https://doi.org/10.23708/PPPPDL (Raclot and Hamdi, 2025).