Holocene history of peatland communities of central Rif (Northern Morocco)

The Maghreb’s Mediterranean coastal edge is home to many peatlands with boreal floristic affinities and high conservation value. This work aims at investigating the Holocene developmental history of these wetlands in Northern Morocco, based on pollen record, loss-on-ignition and radiocarbon dating. First, the comparison between modern pollen spectra and present-day hydrophytic vegetation makes it possible to identify the local pollen signal. Second, while peatlands have existed in the Rif for at least 13,000 years, their initiation mostly by paludification extends throughout the Holocene. Their plant composition remains relatively unchanged for millennia, but swamp undergrowth could locally experience changes in taxa dominance. Mid- to late-Holocene sedimentation changes appear to result from the human-induced regional decline of cedar. The major changes experienced by wetlands occurred recently, due to clearing, burning and overgrazing. Effective conservation policies should be urgently implemented in order to save the last relict peatlands of Northern Morocco.