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Belrhaba, T.; Hakkou, M.; Rey, T.; Aangri, A.; Krien, Y.; Elmostafa, Z.; Leone, F., and Benmohammadi, A., 2024. Shoreline change and climatic variability along the Moulay Bousselham coast (Moroccan Atlantic). Journal of Coastal Research, 40(5), 860–874. Charlotte (North Carolina), ISSN 0749-0208. Sandy coasts in Morocco are increasingly threatened by erosion. It is thus crucial to investigate the extent and causes of shoreline change to propose mitigation strategies to stakeholders. This study investigates the long-term shoreline dynamics of Moulay Bousselham (1949–2016) and its relationship with climate variability indices, namely the North Atlantic Oscillation, East Atlantic Oscillation, and West Europe Pressure Anomaly (WEPA). The analysis, which employs geospatial techniques and the Digital Shoreline Analysis System, reveals significant temporal and spatial variability in shoreline changes characterized by phases of erosion and accretion. The study identifies distinct periods of retreat and growth, highlighting the complex nature of coastal dynamics. The correlation analysis between wave parameters and climatic indices emphasizes the influential role of the WEPA index in controlling winter oceanic phenomena. The winter of 2013/14, marked by the highest WEPA, corresponds to the most energetic conditions in at least 70 years, underscoring the index's significance in understanding local climate variability. While acknowledging methodological challenges and uncertainties inherent in shoreline displacement calculations, the study establishes a noteworthy correlation between the WEPA index and shoreline dynamics. This research contributes valuable insights into the intricate interactions between climate variability and coastal evolution, emphasizing the need for refined methodologies and a comprehensive understanding of factors influencing shoreline changes. [ABSTRACT FROM AUTHOR]

Vapour-phase fumigation with HCl is routinely used to remove inorganic carbon in preparation for the measurement of the concentration and δ13C value of organic carbon in a sample using elemental analysis coupled to an isotope ratio mass spectrometer. Acidification of the sample to be analyzed can lead to the loss of low molecular weight conjugate bases as volatile organic acids during the acidification and/or the drying steps following fumigation, through protonation of the conjugate base and volatilization. Such loss could lead to a severe bias in incubation experiments where 13C-enriched compounds such as acetate are used to trace reaction pathways or metabolites in a cultivation medium or a mesocosm for example. In this work, we enriched a carbonate-free freshwater sediment with 1-13C sodium acetate by 5, 10 and 20 ‰ relative to the δ13C value of the natural organic carbon of the sediment, and then tested the effects of HCl fumigation, drying at 50 °C and drying at room temperature, alone or in combination, on the measured δ13C values. We found that fumigation and drying at 50 °C, alone or in combination, both lead to the loss of the majority of the 13C-enriched acetate spike. [ABSTRACT FROM AUTHOR]

Vapour-phase fumigation with HCl is routinely used to remove inorganic carbon in preparation for the measurement of the concentration and δ 13 C value of organic carbon in a sample using elemental analysis coupled to an isotope ratio mass spectrometer. Acidification of the sample to be analyzed can lead to the loss of low molecular weight conjugate bases as volatile organic acids during the acidification and/or the drying steps following fumigation, through protonation of the conjugate base and volatilization. Such loss could lead to a severe bias in incubation experiments where 13 C-enriched compounds such as acetate are used to trace reaction pathways or metabolites in a cultivation medium or a mesocosm for example. In this work, we enriched a carbonate-free freshwater sediment with 1- 13 C sodium acetate by 5, 10 and 20 ‰ relative to the δ 13 C value of the natural organic carbon of the sediment, and then tested the effects of HCl fumigation, drying at 50 °C and drying at room temperature, alone or in combination, on the measured δ 13 C values. We found that fumigation and drying at 50 °C, alone or in combination, both lead to the loss of the majority of the 13 C-enriched acetate spike.