The coast of Morocco is,in many locations, physically and socio-economically vulnerable to accelerated sea-level rise,due to its low topography and its high ecological,economic and touristic values. Assessment of the ...The coast of Morocco is,in many locations, physically and socio-economically vulnerable to accelerated sea-level rise,due to its low topography and its high ecological,economic and touristic values. Assessment of the potential land loss by inundation and erosion,based on a modeling approach and Geographical Information Systems(GIS),has enabled to identify both locations and the socioeconomic sectors that展开更多
The aim of the present work is to assess the offshore wave energy potential along the Atlantic coast of Morocco.Research works of this paper focus on the identification of the most energetic sites for wave energy conv...The aim of the present work is to assess the offshore wave energy potential along the Atlantic coast of Morocco.Research works of this paper focus on the identification of the most energetic sites for wave energy converters(WECs)deployment.For this purpose,11 sites have been explored;all of them are located at more than 40m depth on the Moroccan Atlantic coast.The wave power at each site is computed on the basis of wave data records in terms of significant wave height and energy period provided by theWaveWatch three(WW3)model.Results indicate that the coast sites located between latitudes 30°30′N and 33°N are the most energetic with an annual average wave power estimated at about 30 kW?m^-1,whereas,in the other sites,the wave power is significantly lower.Moreover,the study of the monthly and seasonal temporal variability is found to be uniform in the powerful sites with values four times greater in winter than in summer.The directional investigation on the significant wave height has shown that for almost all the powerful sites,the incoming waves have a dominant sector ranging between Northern(N)and Western-Northern-Western(WNW)directions.展开更多
In order to evaluate the contamination of the Moroccan Mediterranean coasts by persistent organic pollutants we studied hydrocarbons and linear alkylbenzenes in bivalve tissues (cockles) collected seasonally from seve...In order to evaluate the contamination of the Moroccan Mediterranean coasts by persistent organic pollutants we studied hydrocarbons and linear alkylbenzenes in bivalve tissues (cockles) collected seasonally from several points along the western Moroccan coasts in the Mediterranean Sea. Two fractions corresponding to non aromatic and aromatic hydrocarbons were analyzed by GC/FID and GC/MS. Non aromatic hydrocarbon concentrations vary in the range of 24.1 - 2731 μg/g dry weight (dw) while total n-alkanes vary from 2.2 to 68.2 μg/g. Few exceptions were noted with values up to 243 μg/g (dw), which is high compared to other Mediterranean sites. The presence of an important unresolved complex mixture (UCM) indicated a significant petroleum contamination, confirmed by the identification of 17α(H), 21β(H) hopanes. Biogenic contributions were also detected within the n-alkane distribution (n-C17, n-C18, n-C27, n-C29, n-C17, /Pr, n-C18, /Ph) and by the presence of alkenes. C13, and C14, linear alkylbenzenes were found at concentrations of 478 - 1954 ng/g. and point to pollutant inputs from wastewaters. Polycyclic aromatic hydrocarbons were present in low concentrations below the GC detection limit. The observed seasonal and spatial variations were linked to the magnitude of inputs from marine and land-based pollutant discharges.展开更多
The morphological and volumetric changes of a sandy beach were investigated through a series of two- monthly filed surveys carried out aver a 2-year period from April 2005 to January 2007. This paper discuss the abili...The morphological and volumetric changes of a sandy beach were investigated through a series of two- monthly filed surveys carried out aver a 2-year period from April 2005 to January 2007. This paper discuss the ability of 3-D digital elevation models (DEMs) derived from high accurate data to assess and quantify beach morphodynamics in relation with wave forcing. The methodology and data acquisition are described and consist mainly in the production of interpolated DEMs from which a variety of representations can be made, including as elevation change maps, two-dimensional cross-sections of the beach, calculation of net volume. The results of the analysis highlight seasonal changes in beach morphology due to variations in wave energy. This behavior is characterized by beach erosion and bar decay under high-energy waves and net accretion and bar formation during relatively fair weather conditions. The sand budgets adjustments show that the loss of volume in the winter months is compensated for by accumulation to the beach during summer. This trend suggests that there is a mechanism which controls the beach evolution. The correlation between beach changes and wave energy variations highlights a net relation between them. The results from this in- vestigation state the value of DEMs utilized and demonstrate the efficiency of the 3-D approach employed here to assess the erosion and accretion patterns which would not be visualized using 2-D profiles.展开更多
文摘The coast of Morocco is,in many locations, physically and socio-economically vulnerable to accelerated sea-level rise,due to its low topography and its high ecological,economic and touristic values. Assessment of the potential land loss by inundation and erosion,based on a modeling approach and Geographical Information Systems(GIS),has enabled to identify both locations and the socioeconomic sectors that
基金conducted as part of the research activity within the EMISys research team at the Turbomachinery Lab with the institution’s financial support of Mohammadia School of Engineers and Mohammed V University in Rabat
文摘The aim of the present work is to assess the offshore wave energy potential along the Atlantic coast of Morocco.Research works of this paper focus on the identification of the most energetic sites for wave energy converters(WECs)deployment.For this purpose,11 sites have been explored;all of them are located at more than 40m depth on the Moroccan Atlantic coast.The wave power at each site is computed on the basis of wave data records in terms of significant wave height and energy period provided by theWaveWatch three(WW3)model.Results indicate that the coast sites located between latitudes 30°30′N and 33°N are the most energetic with an annual average wave power estimated at about 30 kW?m^-1,whereas,in the other sites,the wave power is significantly lower.Moreover,the study of the monthly and seasonal temporal variability is found to be uniform in the powerful sites with values four times greater in winter than in summer.The directional investigation on the significant wave height has shown that for almost all the powerful sites,the incoming waves have a dominant sector ranging between Northern(N)and Western-Northern-Western(WNW)directions.
文摘In order to evaluate the contamination of the Moroccan Mediterranean coasts by persistent organic pollutants we studied hydrocarbons and linear alkylbenzenes in bivalve tissues (cockles) collected seasonally from several points along the western Moroccan coasts in the Mediterranean Sea. Two fractions corresponding to non aromatic and aromatic hydrocarbons were analyzed by GC/FID and GC/MS. Non aromatic hydrocarbon concentrations vary in the range of 24.1 - 2731 μg/g dry weight (dw) while total n-alkanes vary from 2.2 to 68.2 μg/g. Few exceptions were noted with values up to 243 μg/g (dw), which is high compared to other Mediterranean sites. The presence of an important unresolved complex mixture (UCM) indicated a significant petroleum contamination, confirmed by the identification of 17α(H), 21β(H) hopanes. Biogenic contributions were also detected within the n-alkane distribution (n-C17, n-C18, n-C27, n-C29, n-C17, /Pr, n-C18, /Ph) and by the presence of alkenes. C13, and C14, linear alkylbenzenes were found at concentrations of 478 - 1954 ng/g. and point to pollutant inputs from wastewaters. Polycyclic aromatic hydrocarbons were present in low concentrations below the GC detection limit. The observed seasonal and spatial variations were linked to the magnitude of inputs from marine and land-based pollutant discharges.
文摘The morphological and volumetric changes of a sandy beach were investigated through a series of two- monthly filed surveys carried out aver a 2-year period from April 2005 to January 2007. This paper discuss the ability of 3-D digital elevation models (DEMs) derived from high accurate data to assess and quantify beach morphodynamics in relation with wave forcing. The methodology and data acquisition are described and consist mainly in the production of interpolated DEMs from which a variety of representations can be made, including as elevation change maps, two-dimensional cross-sections of the beach, calculation of net volume. The results of the analysis highlight seasonal changes in beach morphology due to variations in wave energy. This behavior is characterized by beach erosion and bar decay under high-energy waves and net accretion and bar formation during relatively fair weather conditions. The sand budgets adjustments show that the loss of volume in the winter months is compensated for by accumulation to the beach during summer. This trend suggests that there is a mechanism which controls the beach evolution. The correlation between beach changes and wave energy variations highlights a net relation between them. The results from this in- vestigation state the value of DEMs utilized and demonstrate the efficiency of the 3-D approach employed here to assess the erosion and accretion patterns which would not be visualized using 2-D profiles.