• Energy Research

Healthy wetlands are among the most effective sinks for carbon on the planet, and thus contribute to mitigate climate change. However, in North Africa, coastal wetlands are under high pressure especially from urban sprawl and tourism development, due to the rapid population growth and migration. This paper analyzed the effects of land use/land cover changes on carbon stocks, over 20 years, in six North African coastal wetlands, and estimated the economic value of the carbon sequestered during the considered period. The methodology used combined remote sensing and modeling. The results showed that among the six studied sites, only two (Moulouya and Moulay Bouselham) showed an increase in stored carbon and therefore are potential carbon sinks. In turn, the other four showed a more or less significant loss of carbon, which will likely be released into the atmosphere. The underlying processes that drive changes in carbon dynamics are mainly urban expansion and land use conversion, which often occurs at the expense of the natural habitats surrounding the wetlands. Understanding these processes can provide valuable decision-making information for land use planning, wetlands conservation and carbon reduction policies.

Abstract The Moroccan coast is occasionally confronted with marine submersion events caused by storm surges and tsunamis. The Moroccan historical archives recorded some of these events, such as the storm surge of 2014 CE and the tsunami of 1755 CE. The latter remains the most destructive event the country has ever faced, with major human and economic losses recorded mainly between the two cities of Tangier and Safi. The privileged way to prevent any hazard related to these events is to study their past occurrences and consequences. However, historical records are often very scarce to determine their return periods and evaluate their intensities. Accordingly, the scientific community increasingly uses sedimentary archives from coastal environments, since they offer a viable alternative to historical archives. Several studies using this approach have been conducted on the Moroccan coast in recent years; however, until now, there has been no review dealing with these studies, which is the main objective of this paper. The present review shows that most of the Moroccan sites containing marine submersion deposits are located along the Atlantic coast. The Mediterranean coast remain poorly studied despite the presence of tsunami and storm surge risks. The review draws attention also to the absence of chronological data for most of the marine submersion deposits recognized up to now along the Moroccan coasts, which is a major issue that prevents the determination of the return period of these events.

<div> <div> <div> <p>Recent reductions of sediment transport are observed in Bouregreg River and estuary close to the city of Rabat in Morocco. The cause of this evolution in sediment transport which may be due to human activities (dam, pollution), climate variability and natural events has been investigated from a paleo-hydrological approach. Sedimentological and geochemical analyses of slackwater flood deposits are used to assess the impact of a dam installed in 1974 and the climate change on the evolution of sediment transport during about 60 years. Higher accumulation rate of about 3,64 cm/year is observed between 1950 and 1978, whereas it was much lower about 0,41 cm/year between 1990 and 2017. This strong decrease in sediment rate appears much more due to the impact of dam construction rather than to climate change, however climate change in an increasing concern for the future.</p> </div> </div> </div>

The objective of this study is to investigate the evolution of rainfall and flow in the Bouregreg watershed, and to identify the most vulnerable regions to climate change over a period of 36 years from 1977 to 2013. Results show significant variations between these sub-regions in term of monthly flows and monthly regimes. January and February rainfall amounts are the most affected by the reduction of rainfall since the drought started end of the 1970’s, inducing a reduction of flows at all hydrological stations mainly since 1979. The year 1996 shows very high precipitations over all sub-basins, and also separates two periods with different rainfall time series variations according to two regions over the basin: the region of the Tsalat sub-basin in the Southeast wet and mountainous area (Middle Atlas) shows a durable decrease of rainfall compared to the Ain Loudah sub-basin in the Center-West semi-arid plateau area.