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1

Spatio-temporal structure of natural and anthropogenic land use in a semi-arid watershed: Northwest Algeria

Melalih Ahmed

Journal of Water and Land Development

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2023

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no. 58

110--119

EN

The objective of this study is to map through multisource data, the change in land use structure and quantify its evolution around the semi-arid watershed of Wadi Sarno of Sidi Bel Abbès between 2000 and 2021. To this end, satellite images of 2000 and 2021 have been exploited by remote sensing and GIS, as well as field surveys for verification and validation of the results obtained. The methodology is based on supervised classification by maximum likelihood from the processing of satellite images. The analysis of the dynamics of land use shows that the areas of natural formations (dense forest and bare land) have decreased from 17,560 ha to 15,516 ha, that is to say, a regression of 8.04%, while the anthropised formations (Agriculture, open forest and rangeland, built-up areas, water bodies) have experienced an increase in their surface area, they have gone from 7901 ha to 9945 ha, that is to say, 10.4% of the total surface area of the basin. In the light of these results, it is possible to define priority areas for restoring degraded zones and enhancing natural formations. by giving priority to perennial crops to fix the soil in place and benefit from additional income for the region's farmers. By planting hardy species such as olives, figs, almonds, carob trees and so on. These species have proven their effectiveness and adaptation to local soil and climate conditions.

2

Quantification of solid particle transport in suspension in a stream : Case of Wadi Zeddine Ain-Defla, Algeria

Bouleknafet Zohir, Elahcene Omar

Journal of Water and Land Development

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2023

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no. 56

102--108

EN

Arid and semi-arid areas are characterised by differentiation in meteorological conditions. Sometimes the rains are rare and not very intense and at other times they are dense and very intense, resulting in torrents that often lead to strong soil erosion. Most of the time, the losses occur at the solids level because the erosion effect is too high. In this study, we want to evaluate the transfer of solid sediments as a function of liquid transport in the basin of Wadi Zeddine at Ain Defla in Algeria. To understand this phenomenon, we used the data of liquid flows (Ql, m3∙s-1) and concentration of suspended sediments (C, g∙dm-3), transported in the river, the data collected by the NWRA (National Water Resources Agency), over 24 years have been used to find a relationship between these two quantities, to estimate the quantity of solid transport Qs (kg∙s-1) in the watercourse of the catchment area studied. The results obtained show a good correlation between solid and liquid flows, with a correlation coefficient estimated at 90%, and the average annual sediment supply recorded at the outlet of the Wadi Zeddine watershed is estimated at around 88,048 Mg, which corresponds to 202 Mg∙km-2∙y-1 erosion rate. This value is comparable to those found in other regions with similar hydrological regimes.

3

Mineralogical and Chemical Characteristics of Phosphates from the Djebel Onk Deposits (Tebessa, Algeria)

Tahri Tourkia, Narsis Souad, Bezzi Nacer, Bouzenzana Abdellali, Sekiou Omar, Trirat Tabet, Amrane Theziri, Benselhoub Aissa

Inżynieria Mineralna

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2023

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no. 2, vol. 1

351--359

PL

Algeria has important phosphate reserves (2 billion tons) located in the east of the country at Djebel Onk. This mining district is located in the northwestern part of the Algerian Sahara near the Algerian-Tunisian border. The granulo-chemical and XRD analytical results confirm the phosphate depletion of Bled El Hadba layer and their enrichment in carbonate and dolomite, in comparison with the layer of Kef Essennoun. Phosphorite particles are heterogeneously grained. Although the two deposits are relatively close to each other, they show different mineralogical and chemical characteristics, which may cause the use of different mining exploitation methods.

XX

Algieria posiada ważne rezerwy fosforanów (2 miliardy ton) zlokalizowane na wschodzie kraju w Djebel Onk. Ten obszar górniczy znajduje się w północno-zachodniej części algierskiej Sahary, w pobliżu granicy algiersko-tunezyjskiej. Wyniki analiz granulochemicznych i XRD potwierdzają zubożenie fosforanów w warstwie Bled El Hadba i ich wzbogacenie w węglan i dolomit, w porównaniu z warstwą Kef Essennoun. Cząstki fosforytu są niejednorodnie ziarniste. Chociaż oba złoża znajdują się stosunkowo blisko siebie, wykazują różne właściwości mineralogiczne i chemiczne, co może powodować stosowanie różnych metod eksploatacji górniczej.

4

Use of remote sensing as an indicator of the urban heat island effect: the case of the municipality of Guelma (north-east of Algeria)

Khallef Boubaker

Geomatics, Landmanagement and Landscape

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2023

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no. 3

61--72

EN

The main objective of this study is to show which of the LST-NDVI and LST-NDBI relationships can determine the most accurate index that can be used as an indicator of the effects of urban heat islands in the municipality of Guelma, using Landsat data. 8 OLI/TIRS and the geographic information system. The application of the calculation formulas made it possible to extract the Land Surface Temperature (LST), Normalized Difference Vegetation Index (NDVI) and Normalized Difference Built up Index (NDBI) of the municipality of Guelma for the four seasons of 2019. This calculation led to the determination of the relationship between all three indicators. The results obtained show a strong correlation between the LST and the NDBI for the four seasons of the year. They suggest that the NDBI is an accurate indicator of the heat island effect in Guelma. This indicator can serve as a tool for future urban planning by those in charge of this department. However, there is currently and urgent need to strengthen strategies for reducing the effects of urban heat islands in order to preserve the quality of urban life of the inhabitants and by setting up emergency programs.

5

Urban traffic incident management, using network analysis to improve the evacuation time to healthcare facilities

Saker Adel, Akakba Ahmed

Geomatics, Landmanagement and Landscape

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2023

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no. 3

109--119

EN

The city of Biskra is ranked the second city in Algeria with the highest traffic accident rate. There are multiple causes of accidents that derive from the diversity of traffic. In addition, its geographical location as a crossroads between the northeast and the south of Algeria is a major factor. Biskra is also considered a commercial and industrial city that receives daily large flows of travellers and merchandise. Traffic accidents are a complex problems that is dealt with in several approaches. In this research, from a geographical point of view, we will contribute to improve the trajectory of intervention and evacuation. Therefore, this research paper aims to create a geodatabase including the road network with associated entities to carry out spatiotemporal analyses and evaluate the service area of health facilities in terms of the nearest path. This paper uses GIS tools for evacuation to the public hospital employing a Network Analyst. This study may serve as a decision-making aid for the local authorities of this city in terms of evacuation and intervention in the event of a road accident. It provides real-time information on the location of the accident and the nearest path along with an estimated time. The outputs of these analyses can determine a map of accessibility, which allows for training in order to improve the real-time evacuation. As a result, this approach will lead to the reduction of evacuation time by less than 10 minutes, and thus leading to a decrease in the number of fatalities.

6

Investigation of litho-biostratigraphic characteristics and geographical distribution of Coniacian-Santonian formations: a case study in the Aures Mountains, eastern Saharan Atlas, Algeria

Bentahar Fahima, Defaflia Nabil, Benmansour Sana, Fehdi Chemseddine

Geomatics, Landmanagement and Landscape

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2023

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no. 3

73--94

EN

The Coniacian-Santonian series in the Aures Mountains of northeastern Algeria is characterized by marly-dominated sedimentation processes. This study aims to comprehensively investigate this series by combining lithostratigraphic and biostratigraphic data. The unique paleogeographic position of the Aures basin supports the co-occurrence of diverse paleontological contents in the Upper Cretaceous sediments. The methodology employed in this study includes a detailed bio-lithostratigraphic analysis to subdivide the Coniacian-Santonian series into two distinct sets. The first set comprises alternating marl-limestone units that exhibit a high fossil concentration from the Coniacian age, while the second set mainly consists of marly sediments corresponding to the Santonian age. The results obtained from this study highlight the geographical distribution of litho-biostratigraphic characteristics and reveal the presence of two formations. The lower formation is characterized by carbonated marls intercalated with limestone banks, containing fossils of Peroniceras (Tissotia tissoto) from the Coniacian age. Meanwhile, the upper formation is predominantly marly and indicates the Santonian age by displaying fossils of Palcenticeras polypsis. Furthermore, a biostratigraphic analysis focused on foraminifers allows for the subdivision of the Coniacian-Santonian series in the Aures Mountains into three distinct biozones. The first biozone corresponds to the lower Coniacian age and is identified by the presence of Dicarinella primitiva. The second biozone represents the middle to upper coniacian age and contains Dicarinella concavata fossils. Finally, the third biozone, belonging to the Santonian age, is marked by the occurrence of Dicarinella asymetrica. The boundary between the Coniacian and Santonian series in the Aures Mountains is characterized by the first appearance of Dicarinella asymetrica and Palcenticeras polypsis species. This multidisciplinary study provides valuable insights into the litho-biostratigraphic characteristics and geographical distribution of the Coniacian-Santonian series in the Aures Mountains. The findings make a significant contribution to a better understanding of sedimentary processes and the paleontological content within this region during the Upper Cretaceous period.

7

Estimation of Sediment Concentration Using Sediment Rating Curve Approach in Isser Watershed (North-West of Algeria)

Baloul Djouhra, Ghenim Abderrahmane Nekkache, Megnounif Abdesselam

Ecological Engineering & Environmental Technology

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2023

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Vol. 24, iss. 6

282--291

EN

This paper was elaborated in order to estimate suspended sediment in Isser watershed located in North-West of Algeria. Power functions models by least squares regression were developed to establish rating curves. In total, 2026 pairs of instantaneous water discharge (Q) and instantaneous suspended sediment concentration (C) from the period 1988–1989 to 2003–2004 were used. In order to reveal the temporal impact, four subdivision data are elaborated: all, annual, seasonal and monthly scales. Better estimation of the total suspended sediment yield was obtained by application of the power linear model in monthly division data (-0.16%). When considering efficiency, both models with seasonal scale offered coefficients in order of 0.95%. The approach of correction for models did not improve accuracy of the estimation. The results have indicated for the 16 years of the available data, that the Isser watershed has drained a total of 194.37 million m3 of water and 1.4 million tons of suspended sediments, with a specific degradation of 77 tons/km2/year.

8

Measures to Mitigate the Main Causes of Social Housing Delays in Algeria

Zemra Rachid, Saighi Ouafa

Civil and Environmental Engineering Reports

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2023

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Vol. 33, no. 2

13--33

EN

Social housing in Algeria is carried out with state budget funds in order to eliminate social inequalities and guarantee a decent life to the citizen. However, delays have been observed in the realization. This study aims to examine the main causes and develop guidelines to effectively mitigate delays. Through an in-depth analysis of the literature and formal interviews on the topic of potential risks with construction experts, a list of 67 delay factors was identified. Data was collected through an online questionnaire via Google Forms and semi-structured interviews of a sample professionals established in Algeria. A total of 59 valid responses were analyzed and classified by SPSS software. The results indicate that the 5 most critical causes are: "Delay in payment", "Slow change orders in extra works", "Ineffective planning and scheduling", "Slow change orders in extra quantities", and "Difficulties in financing the project by contractor". Though, the correct implementation of the measures suggested by this study allows government authorities and professionals to deal with the 10 most critical causes that have favored the occurrence of delays in order to successfully implement similar construction projects.

9

Isolation, characterization and growth assessment of biodegrading chlorpyrifos-methyl Bacillus species isolated from Algerian soil

Slimani Hanane, Abdi Akila, Branes Zidane

Przegląd Naukowy Inżynieria i Kształtowanie Środowiska

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2022

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Vol. 31, No. 2

135--146

EN

Chlorpyrifos-methyl (CM) is a broad-spectrum organophosphate insecticide, which is widely used in pest control. In this research, the isolation, and biochemical and molecular identification of bacterial strains obtained from three soils located in northeastern Algeria were carried out, as well as the evaluation of their ability to grow in the presence of CM. Out of 48 bacterial isolates between Gram-negative and Gram-positive identified, several were able to grow on mineral agar with at least 25 mg·l–1 of CM. Four bacteria showed the best growth capacity, were identified as Bacillus sp. H1-80, Brevibacterium frigoritolerans strain WJB99 and two Bacillus sp. strains GL5. The strains were tested for their ability to grow on liquid media with CM as the sole energy and carbon source. In general, these strains showed slow but significant growth visualized by the 600 nm turbidity control, suggesting that they could be used for bioremediation applications of CM polluted soils.

10

How do mussel provenance and spat size affect mussel aquaculture performance in the South-Western Mediterranean (Algeria)?

Belgaid Imene, Nacef Lamri, Alioua Zakia, Bachari Nour-El-Islam

Oceanological and Hydrobiological Studies

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2022

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Vol. 51, No. 3

239--256

EN

The objective of this research was to study the effects of size and spat origin of farmed Mytilus galloprovinciallis in mussel longlines in the east of Bou-Ismail Bay (central coastal Algeria, south-western Mediterranean). The study was conducted from October 2017 to July 2020 in the east of Bou-Ismail Bay. The mussel spat were obtained from four origin sites (Tlemcen, Tenes, Ain Tagourait and the study site) and were seeded on three spat sizes (10–30, 30–60 and >60 mm). The production performance of this species was analysed on 284 random mussel plots using average physical product (APP), gain and loss rates, condition index (CI), percentage of edibility (PE) and shell thickness index (STI). Apart from the CI and loss rate, the performance indicators showed significant differences according to spat size and source (p < 0.05). Overall, the highest APP (4.3) was recorded for the small seeded mussels (10–30) mm and for those originating from Tlemcen, near finfish cages (APP = 4.14). These individuals exhibited more efficient growth and physiology for commercial size and performed better than the spat collected at the study site. The results can be considered a valid contribution to best farming practice for optimising the production of this species in Algeria. It also contributes to the development of integrated multitrophic aquaculture (IMTA) methodology, which is suitable for use in the oligotrophic Western Mediterranean.

11

Evaluating four remote sensing based models to estimate latent heat flux in semi-arid climate for heterogeneous surface coverage of western Algeria

Oualid Tewfik A., Hamimed Abderahmane, Khaldi Abdelkader

Journal of Water and Land Development

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2022

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no. 55

259--275

EN

Optimal estimation of water balance components at the local and regional scales is essential for many applications such as integrated water resources management, hydrogeological modelling and irrigation scheduling. Evapotranspiration is a very important component of the hydrological cycle at the soil surface, particularly in arid and semi-arid lands. Mapping evapotranspiration at high resolution with internalised calibration (METRIC), trapezoid interpolation model (TIM), two-source energy balance (TSEB), and soil-plant-atmosphere and remote sensing evapotranspiration (SPARSE) models were applied using Landsat 8 images for four dates during 2014-2015 and meteorological data. Surface energy maps were then generated. Latent heat flux estimated by four models was then compared and evaluated with those measured by applying the method of Bowen ratio for the various days. In warm periods with high water stress differences and with important surface temperature differences, METRIC proves to be the most robust with the root-mean-square error (RMSE) less than 40 W∙m-2. However, during the periods with no significant surface temperature and soil humidity differences, SPARSE model is superior with the RMSE of 35 W∙m-2. The results of TIM are close to METRIC, since both models are sensitive to the difference in surface temperature. However, SPARSE remains reliable with the RMSE of 55 W∙m-2 unlike TSEB, which has a large deviation from the other models. On the other hand, during the days when the temperature difference is small, SPARSE and TSEB are superior, with a clear advantage of SPARSE serial version, where temperature differences are less important.

12

Analysis of groundwater quality in the lower Soummam Valley, North-East of Algeria

Ghodbane Messaoud, Benaabidate Lahcen, Boudoukha Abderrahmane, Gaagai Aissam, Adjissi Omar, Chaib Warda, Aouissi Hani Amir

Journal of Water and Land Development

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2022

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no. 54

1--12

EN

Analysis of groundwater quality in the alluvial aquifer of the lower Soummam Valley, North-East of Algeria, was realised through the application of multivariate statistical methods: hierarchical cluster analysis (HCA) in Q and R modes, factorial correspondence analysis (FCA), and principal component analysis (PCA), to hydrochemical data from 51 groundwater samples, collected from 17 boreholes during periods of June, September 2016 and March 2017. The objectives of this approach are to characterise the water quality and to know the factors which govern its evolution by processes controlling its chemical composition. The Piper diagram shows two hydrochemical facies: calcium chloride and sodium bicarbonate. Statistical techniques HCA, PCA, and FCA reveal two groups of waters: the first (EC, Ca2+, Mg2+, Cl-, SO42- and NO3-) of evaporitic origin linked to the dissolution processes of limestone rocks, leaching of saliferous soils and anthropogenic processes, namely contamination wastewater and agricultural activity, as well marine intrusion; and the second group (Na+, K+, and HCO3-) of carbonated origin influenced by the dissolution of carbonate formations and the exchange of bases. The hermodynamic study has shown that all groundwater is undersaturated with respect to evaporitic minerals. On the other hand, it is supersaturated with respect to carbonate minerals, except for water from boreholes F9, F14, and F16, which possibly comes down to the lack of dissolution and arrival of these minerals. The results of this study clearly demonstrate the utility of multivariate statistical methods in the analysis of groundwater quality.

13

Assessment of Biotope Suitability of Desert Locust (Schistocerca gregaria) in the Region of Hoggar (Southern Algerian Sahara)

Boultif Meriem, Boulghobra Nouar, Bakroune Nourelhouda, Deghiche-Diab Nacima

Journal of Ecological Engineering

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2022

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Vol. 23, nr 9

171--180

EN

Upsurges of desert locusts can cause heavy economic and agricultural losses and threaten the food security of millions of people over dozens of countries. Therefore, monitoring and spatial delimitation of their habitats are necessary for biological control studies and sampling, especially on large surfaces. This study aimed to assess and map suitable biotopes for desert locusts in southern Algeria, through a GIS tool, by integrating multicriteria analysis (Analytical Hierarchy Process) as a decision-making tool for preventive methods, biological control and research. The result is a resolution map, classified into four different zones according to pixel values. The results revealed that 28.51% of the study area is an unsuitable biotope for desert locusts, 35.92% is a survival biotope, 19.5% is a suitable biotope mainly for breeding and eggs lying and 16.05% is highly suitable for desert locust gregarization and concentration. This study offers a simplified mapping procedure to assess locust habitats for decision-making and studies in large areas.

14

Effect of the agriculture on the quality of groundwater in the alluvial aquifer of the Tadjenanet area (eastern Algeria)

Khedidja Abdelhamid, Dib Imen

Geomatics, Landmanagement and Landscape

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2022

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no. 3

45--57

EN

The region of Tadjenanet is in eastern Algeria in the high plains, characterized by a varied age detritus Mio-Plio-Quaternary. Some geological formations can be an important source of groundwater (alluvial sand, shell limestone, gravel). Its location in semi-arid area involves evaporation pronounced even tilt the balance in a chronic deficit, excluding periods characterized by rainfall events. Agriculture in the study area is the first socio-economic activity and the largest consumer of water resources. It is therefore necessary to consider for effective water management. Indeed, the combination of hydrogeological and hydro chemical geological mapping, geophysics, harvested from field data and their interpretations can be an excellent tool for deciding the suitability of water for irrigation. The analysis of the physicochemical data shows an increase in the concentration of nitrates reaching 200 mg · l–1, as well as the analysis by the Richards SAR parameter shows that most groundwater samples are generally suitable for agricultural purposes with 33%, belong characterizing poor quality. Indeed, the groundwater in the region generally requires prior treatment before consumption and use depending on the type of crop. The assessment of the quality of the water in the region and its consequences on the soil and the types of crops has enabled the authorities concerned to manage the water supply adequately to preserve and protect this vital source for the future from any risk of contamination.

15

Breeding Ecology of the Iberian Chiffchaff Phylloscopus ibericus : First Data from North Africa

Bougaham Abdelazize Franck

Polish Journal of Ecology

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2021

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Vol. 69, nr 1

51--56

EN

Till now, the breeding biology of several North African bird populations has been little studied, particularly that of the southern populations of Iberian chiffchaff Phylloscopus ibericus. In the present study, total of 31 nests of Iberian chiffchaff were monitored in the northeastern Algeria during 2013-2017. The nesting period, clutch and brood sizes, and reproductive success of the species were determined. The first egg-laying dates of the first broods were spread over the first twenty days of April. There were significant among-year variations in nesting seasons. The Iberian chiffchaff clutch sizes averaged 4.51 eggs. The number of hatchlings and fledglings averaged 4.09 and 3.54 nestlings, respectively. There is no correlation between the nest height above the ground and the hatching and the breeding success of the species. Predation and nest abandonment were the main causes of the breeding failure of the Iberian chiffchaff in studied population, however, in general the breeding success was high – 80.7%. Breeding data for the Iberian chiffchaff at the southern edge of its breeding range in North Africa show smaller clutches and production of fewer young compared to the common chiffchaff Phylloscopus collybita in Europe.

16

Water management and the agricultural development constraints in the Algerian Sahara: case of the M'Zab Valley

Zegait Rachid, Bensaha Hocine, Addoun Tayeb

Journal of Water and Land Development

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2021

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no. 50

173--179

EN

In Algeria, modern agriculture was introduced in the Saharan region through the implementation of the law n° 83–18 of August 13, 1983, relating to access to agricultural land ownership (Fr. Accession à la Propriété Foncière Agricole (APFA) in French). This law was hugely successful and sparked a real enthusiasm for this type of activity, which resulted in an expansion of agricultural areas at the M’Zab level, similar to that observed in other Saharan regions. Over the past decades, the agricultural area has declined markedly (–0.4%), which was due to multiple causes, including ecological problems, such as urban discharges and the rise in the water level. So far, little research has been done to assess the agricultural situation and irrigation in this region. The objective of this work is to analyse and discuss the constraints and impacts of water and agricultural management on sustainability of the ecosystem in the Saharan environment. This work is based on extensive research, which has been carried out in the M’Zab region on the oasis system and its evolution. It was enriched with dozens of direct surveys, performed among farmers working in agricultural areas. The results show that agricultural development and the sustainability of farms in this region face several technical and social constraints, the most important of which are the workforce-related problems and water management. Several measures have been recommended to be taken not only to preserve the ecosystem but also to give significance to the large investments made by the public authorities.

17

Using RUSLE and GIS for the soil loss assessment in arid regions: The case of the Ain Sefra catchment in the Ksour Mountains, Algeria

Melalih Ahmed, Mazour Mohamed

Journal of Water and Land Development

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2021

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no. 48

205--214

EN

The loss of soil quality due to erosion is a global problem, particularly affecting natural resources and agricultural production in Algeria. In this study, the Revised Universal Soil Loss Equation (RUSLE) is applied to estimate the risk of water erosion in the Ain Sefra arid watershed (Algeria). The coupling of this equation with Geographic Information Systems (GIS) allows to assess and map the soil loss rates. The land erosion is influenced by many control variables, such as the topographic factor of the terrain and the length of slope (LS factor), rainfall erosivity (R factor), sensitivity of soil to erosion (K factor), presence of vegetation (C factor) and the antierosion cultivation techniques (P factor). To calculate the average annual soil loss, these five factors were considered and multiplied in the RUSLE Equation. The result shows that the average rate of soil loss is estimated at about 5.2 t·ha–1·y–1 over the whole watershed. This study is the first of its kind in the region and aims to assess the soil loss caused by water erosion processes in this arid zone. Consequently, it is essential to take real intervention measures in these upstream areas in order to combat this scourge, based on priorities ensuring the sustainable management of natural resources in the study area.

18

Estimation and management of the future evolution of groundwater water demand in the Taoura region, North-East Algeria

Rouaibia Farid, Sayad Lamine, Attoui Badra

Journal of Water and Land Development

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2021

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no. 49

195--203

EN

Evaluating the capacity to meet the need of water is crucial in order to fulfil expectations of managers, particularly in the Mediterranean area. The region is risk in terms of resources available as well as a steadily increasing in demand for water. The frontier drain of the city of Souk Ahras is located at the extreme Northeast of Algeria, on the Algerian-Tunisian borders, the study region includes eight city, which are Taoura, Drea, Zaârouria, Merahna, Ouillen, SidiFredj, Heddada and Khedara, these are relatively poor in surface water, but groundwater has always been the main water resource. The region’s population is around 93,000 inhabitants, 45% of them living in rural areas. Annual average precipitation is approximately 470 mm∙y–1, but it is distributed unequally in space and time. The average supply water varies from one zone to another and the coverage of demand by groundwater in the region remains low and does not meet all needs. Faced with the regions socioeconomic growth and development, this situation is expected to worsen in the future. In this context, the WEAP (Water Evaluation And Planning system) model was applied to simulate the water balance and assess strategies for the sustainable management of water resources and makes it possible to explore different scenarios, in order to choose the desired scenario to ensure the sustainable development of the sub-basin of the border until 2050. The availability of drinking water permanently in rural areas is a factor in the stability of a population and a means of combating the rural migration and the congestion of urban centres.

19

The Effects of Delays in Algerian Construction Projects: an Empirical Study

Salhi Roumeissa, Messaoudi Karima

Civil and Environmental Engineering Reports

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2021

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Vol. 31, no. 2

218--254

EN

This paper examines the effects of delays in the Algerian construction industry in order to identify the various critical aspects of the causes for improving the economy in the construction sector. A questionnaire survey was conducted to assess the perceptions of all players in the construction industry, which led to the identification of the most significant impacts of delays. The results show that ten main effects of delays in the construction sector are at the origin of many constraints that have a negative impact on the economy of the country. Further, the factor analysis technique was performed to categorize the identified effects into main groups, and it yielded 5 groups (factors). As an important contribution, the relationship between these groups was tested using the SMART-PLS, and a structural model has been developed. Also, a comparative study with other previous works on the most critical effect of delays in construction projects has been conducted and the results show that the main effects of delays in the construction industry are at the root of many constraints in reaching and achieving the objectives.

20

Specific features of the compositional construction of historical mosques of Algeria as the basis for their preservation and restoration in the original form

Ivashko Yuliia, Rezga Kouider

Wiadomości Konserwatorskie

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2020

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Nr 61

80--84

EN

The article were analyzed the specific features of the spatial composition of authentic mosques of the Maghreb countries. It was determined that the traditional compositional scheme of the Maghreb mosque was built on a combination of the horizontal building of the mosque, often domeless one, and a vertical minaret of simple geometric shape. It was studied tha the Khariji mosques were built in the same type. The appearance of the composition with a dome or domes is associated with the period of the Ottoman rule in Algeria since this type of mosque composition is borrowed from Turkey.

PL

W artykule zostały przeanalizowane cechy kompozycyjne oryginalnych meczetów państw Maghrebu. Stwierdzono, że u podstaw tradycyjnej kompozycji meczetów Maghrebu leży kombinacja horyzontalnego budynku meczetu, często bez kopuły, z wertykalnym minaretem o prostym, geometrycznym kształcie. Ustalono, że ten sam typ reprezentują meczety Kharijitów. Zjawisko kompozycji meczetu z kopułą lub z kilkoma kopułami związane jest z okresem osmańskim w Algerii – ten typ meczetu został tutaj przyniesiony z Turcji.