The recent earthquakes in Algeria have caused significant human and economic losses. The frequent occurrence of damaging earthquakes clearly demonstrates the urgent need of study on seismic risk assessment methods of buildings to effectively reduce the impact of earthquake in Algerian cities. This article contributes to the development and the application of a seismic risk method, appropriate to Algerian building specificities. This method considers five damage levels, defined accordingly to macroseismic intensity and the seismic quality of the building by means of a vulnerability index. The present paper summarises the development of a tool to integrate seismic hazard and structural information and support the decision making process in identification of seismic risk. This tool could be used in the inspection of buildings and the optimal prioritisation of strengthening and preventives remedial actions that are necessary prior to a major earthquake event.

Algiers is the political and economic capital of Algeria. The city drains a large part of the activities of the country with intense road traffic. This road traffic is the main source of air pollution, followed by industry and waste combustion. An application of the new road traffic emission model, called EMISENS, is performed to build road traffic emission inventories for the Algiers region. These emission inventories are then used as input to the MM5/CHIMERE system to estimate air pollution. The objective of this study is to propose a methodology to improve the quality of emission inventories, and to validate results. First, by studying the correlation between observed measurements and data concerning cadastre of primary pollutants emitted mainly by road traffic, then by comparing the pollutants concentrations from observed measures with the simulated concentrations with the model of chemistry-transport CHIMERE.

L’urbanisme et la mobilité contraignent fortement les conditions environnementales présentes et futures des grands centres urbains. L’extension désorganisée des villes algériennes engendre aujourd’hui de multiples risques liés au secteur des transports. La pollution de l’air représente l’un de ces risques.L’objectif de cette étude est de développer une méthodologie permettant d’évaluer les émissions de polluants atmosphériques dues au trafic routier. La méthodologie est basée sur un couplage entre SIG et modélisation déterministe pour mieux représenter la répartition spatio-temporelle des émissions.Elle est appliquée à la ville d’Oran en Algérie, dont on montre que la croissance du tissu urbain, et plus particulièrement son étalement en périphérie, sur la période 1966-2015 a induit un transfert des populations du centre-ville vers les pôles périphériques de Bir El Djir, Es Sénia et Sidi Chahmi. Cet étalement est confirmé par l’étude d’une série chronologique d’images satellitaires. Cette évolution de la forme urbaine génère un besoin en mobilité accru et aggrave les problèmes de circulation et de congestion de véhicules fonctionnant à l’énergie fossile qui est la source d’émissions polluantes significatives dont l’impact négatif sur la santé et l’environnement n’est plus à démontrer.La réalisation d’un cadastre des émissions polluantes est une étape essentielle afin d’évaluer la qualité de l’air sur la région d’Oran. Ces émissions sont ici quantifiées dans le temps et dans l’espace grâce à l’application du modèle EMISENS, à partir de comptages de véhicules. Compte tenu de l’évolution du tissu urbain et du transport, ces émissions devraient continuer à augmenter en raison des besoins en mobilité induits par l’étalement ininterrompue de la ville et par la forte attractivité que le centre de la ville exerce sur les citoyens de l’agglomération d’Oran.

The northwestern part of Algeria is characterized by a semi-arid climate which has created semi-permanent rivers and dams with low filling rates. It is important to preserve the water resource, which is becoming increasingly scarce. Additionally, it is worth indicating that the mobilized surface waters are continually under threat of significant organic pollution. Indeed, the dam of Cheurfas II, in the northwestern part of the country, is indicative of this situation. In order to establish a diagnosis of the state of the temporal evolution of water quality, time series of 11 variables indicating the presence of organic pollution in this dam were thus analyzed. The data collected were analyzed using the Mann-Kendall test to look for significant trends and the Webel-Ollech test to detect the presence of seasonality. The results obtained showed increasing trends in dry residues, organic matter, phosphates and dissolved oxygen. However, variables like BOD5, COD and NO-3 showed decreasing trends. As for the variables NH+4, NO-2 and pH, they presented no trend. Finally, the water volume of the dam exhibited a significant increase. In addition, no seasonality was detected in the variables studied, with the exception of the PO43- time series and water volume. These findings indicate that the watershed of the dam received pollutants from different origins, in particular industrial pollutants. This makes water biodegradability difficult to achieve.

In Algeria, the alternative to the absence of these air pollution measurement networks can come from the recent development of electrochemical sensor technologies for air quality monitoring which arouses a certain interest because of their miniaturization, low energy consumption and low cost. We developed a low-cost outdoor carbon monoxide analyzer called APOMOS (Air pollution Monitoring System) based on electrochemical sensor managed by microcontroller. In order to validate the APOMOS system, the recorded measurements are compared with measurements taken by a conventional analyzer. Comparison of the measurements resulting from conventional analyzer and those resulting from the APOMOS system gives a coefficient of determination of 98.39 %.

Background: The effect of confinement due to the coronavirus disease 2019 (COVID-19) pandemic on air pollution has been investigated in several cities. Indeed, the concentration of the main air pollutants have decreased significantly due to the decline in activities consuming fossil fuels. However, it was found that the concentration of ...