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![The process of moisturizing dry winds by the oasis effect phenomenon. [5]](profile/Atef-Ahriz/publication/322308201/figure/fig4/AS:580485551017984@1515409948286/The-process-of-moisturizing-dry-winds-by-the-oasis-effect-phenomenon-5.png)
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![Figure 3: Situation of RIGH valley. [3]](profile/Atef-Ahriz/publication/322308201/figure/fig1/AS:580485551669248@1515409948187/Situation-of-RIGH-valley-3_Q320.jpg)
![Figure 4: Ksour and cities of RIGH valley. [4]](profile/Atef-Ahriz/publication/322308201/figure/fig2/AS:580485551267840@1515409948218/Ksour-and-cities-of-RIGH-valley-4_Q320.jpg)
Despite the severity of the SAHARA Desert from many aspects, the man was able to confront it, and to build great human settlements distributed in different areas as the REG of Mzab Valley, the ERG of Righ Valley, Hoggar Mountains ... And many others points of human life.
These Settlements called SAHARAN Ksour, which become today a valuable archite...
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Province of Guilan is located on the southern coast of the Caspian Sea. The province enjoys particular features geographically and continentally, humidity and abundant rainfall are widely effective in shaping of unique traditional architecture of this region. Guilan province can be divided into two regions in terms of climatic zones, plains and mou...
Citations
... Although previous studies have documented general Urban Heat Island and heat vulnerability issues as cities expand [16], linkages between specific measurable parameters of density and on-the-ground thermal comfort remain inadequately characterized. Much of the existing work has focused on isolated factors like vegetation, geometry, wind, and materials [7][8][9][17][18][19], rather than combined effects of density, size, and spatial arrangements on neighborhood thermal environments. ...
Rapid urbanization across hot arid environments transforms local microclimates, yet linkages between density, layout, and outdoor thermal comfort remain inadequately characterized. This study investigates these correlations in the desert city of Biskra, Algeria. We conducted extensive in-situ measurement campaigns during peak summer and winter periods across six neighborhoods spanning low to high-rise density fabrics. We captured air temperature, humidity, and wind velocity to enable thermal comfort assessment via the Effective Temperature (ET) and Equivalent Temperature (TEK) stress indices. Index sensitivity to density metrics from 23–86% was explored through One-Variable-At-A-Time (OVAT) analysis. Results show marked summer comfort deterioration with rising density due to constrained ventilation. However, higher densities demonstrate superior winter warmth through wind blocking despite reduced sunlight exposure. Sharp nonlinear differences emerge between seasons. Precision density thresholds prove difficult to define conclusively given typological diversities. However, indicative ranges tied to hazards are identified, providing guidelines for informed climatic adaptation. This research delivers vital evidence to advance bioclimatic strategies for enhancing habitability amidst urban expansion across delicate hot deserts.
... 3%, is urbanized (Ahriz et al., 2017). With its rugged terrain and remote locations, the Sahara presents a significant challenge in discovering ancient sites in the region. ...
... While acknowledging potential concerns, it is important to embrace archaeological best practices by understanding data limitations and practising cautious prediction. For predicting with standard archaeological data, MaxEnt currently serves as the most suitable tool (Kamermans, 2007;Kohler & Parker, 1986;Verhagen & Whitley, 2012 (Ahriz et al., 2017;Cote, 2005). Although Ksours hold architectural and urbanistic value as historic landmarks of modern-day Saharan cities, they are unfortunately being neglected and left to deteriorate (Hammoudi, 2012). ...
The Saoura region, a renowned oasis in North Africa with heritage and archaeological significance of both national and universal importance, has witnessed a gradual deterioration over time. This research involves archaeological predictive modelling, aiming to create models capable of predicting the likelihood of discovering archaeological sites, cultural resources or evidence of past landscape use within a specific region. The study specifically focuses on predicting the locations of historical sites in the Sahara Desert, employing the maximum entropy (MaxEnt) model and six geo‐environmental criteria, including slope, elevation (digital elevation model [DEM]), distance from water, normalized difference vegetation index (NDVI), fertility and proximity to palm groves. The research is based on data from 58 historical sites and includes an assessment of the model's accuracy. The study highlights the remarkable significance of the fertility variable, which accounts for 94.1% of the predictive influence, making it the most crucial geo‐environmental factor in forecasting the location of historical sites in the Sahara. This underscores its pivotal role in shaping settlement patterns and subsistence strategies within the region, followed by the distance variable from the palm cove (3.2%) and the distance variable from the river (2.3%). The MaxEnt model proves to be suitable for predicting historical site positions, with an impressive average area under the ROC curve (AUC) score of 0.859, reflecting its effectiveness. Notably, areas with a high prediction probability are predominantly situated near the Saoura Valley. The study's findings hold the potential to assist planners in safeguarding archaeological sites by avoiding areas where historical sites are likely to be present.
... One of the largest and harshest deserts in the world, the desert of the Maghreb regions (SAHARA desert) spans more than 1500 km 2 from North to South and 1200 km from East to West. It is located on 8.5 million square kilometers, all of which are arid, with the exception of 200 thousand kilometers, or about 3% of the planet's surface, that are considered urban areas (Ahriz et al. 2017). Algeria has many inaccessible, distant places, making it difficult to find ancient sites there. ...
... The Saharan Ksours were cleverly placed in the vast Sahara desert; some were located on the edge of the trade routes that crossed the desert, such as the gold lines that connected African nations like Ghana, Mali, and Sunray with the cities of the North; other Ksour were scattered in areas where water was accessible. Due to all these causes and influences, SAHARA had several varieties of ksour, which were found in many valley-like regions, including the MIZAB valley, Ziban, Souf, Righ, and Touat in the far western Sahara (Cote 2005;Ahriz et al. 2017). The ksar constitutes, by its architectural and urbanistic value, one of the historical landmarks of the current Saharan cities, but which unfortunately continues to sink into neglect. ...
The region of Saoura, bounding in heritage and archaeological potential of national and universal importance. The paper’s major goal is to contribute to the literature by providing a hybrid method of GIS-GeoTOPSIS-AHP for archaeology prediction. The results indicate that 48.48% of the Ksours are located in areas that had very high potential and 42.42% are located in high potentiality areas and representing 0.16% and 1.25% of the total area. The model’s ability to predict site locations with reasonable accuracy is expressed by the model gain, which is equal to 98%, it is considered a strong predictive model.
... The Sahara Desert is considered as amongst the largest and harshest deserts in the world along more than 1500 kilometers from south to north and 1,200 km from west to east, situated on 8.5 million km² are all barren except 200 thousand km² which are considered as urban areas which are nearly 3% of the global surface (Ahriz et al. 2017). The area of the desert differs as a result of changes over time that is expansion and contraction (Arrit, 1993). ...
... A number of African countries are covered by the Sahara Desert and these are Tunisia, Chad, Egypt, Mauritania, Mali, Sudan, Morocco, Niger, Libya, and Algeria. The difficulty of urbanizing the desert is due to several reasons as the vastness of its area, the harsh climate, and water scarcity, but the cause of the diversity of the human settlement is mainly due to its different natures of the surface factor, which is changing from sweat sandy to parchment flat salty soil, rocky areas, and the arid mountains (Ahriz et al. 2017). ...
Built on the notion of 'cities as forces for good' (CFG), the purpose of this chapter is to dissect the problematique of reclaiming and greening degraded spaces in Africa's drylands for urban development. The focus of the chapter is on the Sahara and the Kalahari deserts. The chapter adopts a critical literature review anchored in case study analysis and reflexive methodology. These methodologies are critical for constructing and reconstructing reality in a way that speaks to pragmatism. Literature reviews point to the visioning of the future Sahara and Kalahari deserts in which complexes of regional cities arise. The cities become endogenous attractors of populations and pose newer solutions to the challenges that existing cities have today, of pollution, congestion, sprawling, and shrinking job markets. Indeed, the next desert complexes will act as paragons of cities as forces for good. Decentralized mechanisms for energy, water, food production, and waste management are proposed.
... The fundamental environmental factors that influence the thermal comfort of the inhabitants are: the ambient air temperature, the radiant temperatures of the surrounding surfacesthe humidity of the air and air movements [5]. In general, southern Algeria is one of the largest and driest deserts in the world, more than 1,500 km from north to south and 1,200 km from east to west, located on 8.5 million km 2 [6]. The climate is hot and dry in the summer with mild nights and mild days in the winter. ...
In traditional cities of hot and arid climate regions, roofs are usually the surfaces most exposed to intense sunlight in summer. This leads to high temperatures inside the houses and forces the inhabitants to escape to the terraces at night. On the other hand, some residents use air conditioning and therefore increase energy consumption. This work aims to study the contribution of a double skin roof coupled with a thermo-reflective paint on the reduction of indoor temperature and energy consumption in house located in the Ksar of Beni Isguen in southern Algeria. Firstly, the problem of overheating was identified through temperature and humidity measurements for traditional dwelling in hot season. Secondly, a model of double skin roof coupled with thermo-reflective paint was developed and numerically simulated using TRNSYS software. The obtained results showed that in summer, the temperatures in traditional houses are high compared to the comfort zone. The average indoor operating temperatures exceeded 37 °C during different hours of the day, over the investigation period of three representative days of hot season. Nevertheless, the proposed model reduces the indoor operative temperature by 5 °C. Also, the model was validated against in situ measurements, whose results showed a consistency between the measured and simulated temperature values. In addition, thermal simulation results performed over a period of one year indicate that the overall energy consumption required for cooling loads is reduced by 572 kWh i.e. 66% when optimizing the roof thermal performance.
... Climate has been the main environmental factor that has influenced the evolution of vernacular settlements and building design over time (Bouchair, 2003). For this, the developments of human settlements were made in the form of Ksour ( Ahriz and al, 2017). These have been used in Algeria's hot and dry climate in response to harsh local environmental conditions. ...
In the hot and arid regions of southern Algeria, and since the past there are Saharan cities, which necessarily rely on their logic of Organization and development. These are considered as an important space to adapt to the harsh climatic conditions of the Saharan environments. However, these oases recently witnessed major changes; they are characterized by its fragility and its limitations to accommodate a surplus of
human settlements. These changes can lead to a risk in destroying the image of
these cities. To do this, the concept of Sustainable Development is becoming an
integral part of the planning practices adopted by human beings. On the other
hand, despite the anarchic nature of Algerian cities, several traditional practices have been made to adapt to the spatial and environmental. The M'Zab Valley is one of the existing examples of oases cities that give us a lesson in urban
planning and architecture. The Valley contains Ksour with their palm groves,
which introduces its logics of adaptation to the local context through local knowledge with implication of the human-culture-climate. Thus, this study focuses
on shedding light on the ancestral urban and architectural practices adopted by
local people to adapt to severe social, spatial and climatic requirements. The study is based on an analytical approach that focuses on observations of urban and architectural development and planning methods in the M'Zab valley to draw lessons to be learned in order to face the major challenges of the er.
... of Knadsa in the Wilaya of Béchar . The ksour of the M'Zab valley are one of the most famous examples of traditional Saharan cities with these wonderful practices adopted since their construction (Ahriz, 2017). The Valley conceals ksour with their palm groves, introduces its marvelous logics of adaptation through local know-how with a synergy between man, culture and climate. ...
In traditional cities known as "Ksar", several types of roofs have been installed to improve indoor thermal comfort during the winter. Including: terrace roof, vaulted roof, etc. However, new extensions have appeared called "the new ksour" which have built by inspiring old Ksur. These latter testify to constructive changes, namely: the use of non-local materials, new roof construction techniques, etc. The Ksar of Béni Isguen in Southern Algeria is one of the traditional cities which its houses built with the traditional terrace roof. On the other hand, Béni Isguen’s Ksar has a new extension called “Ksar of Tafilelt” which has new changes namely: the use of concrete roof. The work presented in this paper is therefore based on real in situ measurements inside the homes of Béni Isguen and Tafilelt Ksur in winter. The study is also interested in making comparative study between the levels of thermal comfort between two cases in these two Ksur. The object is to study the role of roofs to control temperature variations in order to obtain pleasant thermal comfort. The results indicate that in winter conditions, the level of comfort felt in the case of Béni Isguen is pleasant. While, the level of comfort felt and measured in the new Ksar “Tafilelt” is beyond the range of Comfort especially in the upstairs spaces at night. On the other hand, the surface temperatures of the roofs in the old Ksar are acceptable and they are not pleasant in some hours of the day in Tafilelt.
This study is dedicated to exploring the Ksurian heritage of the Algerian Sahara, aiming to reveal the abundance and variety embedded within each ksar. Employing a comprehensive analytical approach, we meticulously examine four fundamental aspects: the urban layout, the dwellings, the materials utilized, and the construction techniques employed. To accomplish this research, extensive field visits were conducted, encompassing photography, on-site surveys, and engaging discussions with experts to gain profound insights into the distinctive characteristics of each region. Our findings unveil a remarkable and diverse heritage, exhibiting variations from one region to another, ultimately reflecting the unique traditions and capabilities of the Saharan population.
With climate change and the recurring heat waves in arid lands, human well-being and activities in oasis settlements can be critical subjects for the ongoing years. This paper introduces a methodological approach to investigate the potential passive cooling effect inside the oasis palm groves, their spatial characteristics, and microclimatic thresholds. Based on the Physiological Equivalent Temperature (PET) index, the paper evaluates oasis palm groves’ ability to ensure a neutral human outdoor thermal comfort zone. The research aims to determine guidance of an optimal and nearly optimal thermal comfort threshold based on a series of parametric scenarios of oasis configurations. The study provides a cross of 12 ideal oasis scenarios. The paper evaluates the oasis cooling effect and thermal comfort and recommends aligning urban planning with thermal thresholds. Results reveal that PET neutral zone can be assured into ranges of 29°C to 37°C, 19°C to 20°C, 55% to 58%, and 1m/s to 2m/s of mean radiant temperature, air temperature, relative humidity and air velocity, respectively. The results refer policymakers and urban planners to invest in the passive cooling effect of the oasis palm grove in future urban design strategies to maintain the maximum neutral comfort hours during heat waves.
The water, a built environment, and a palm grove are an impressive trilogy making up the formidable oasis, rendering it strong enough to survive the harsh desert climate. Furthermore, the interaction between them creates several natural and physical phenomena. This research discusses the oasis effect, one of the most significant phenomena in the oasis ecosystem; this effect has been treated as a cooling phenomenon in theories and mathematical models. Therefore, we aimed to examine the impact and limits of this phenomenon in regard to the microclimate of oases through digital simulation, using the SPUCAL_oec software (Simulation Platform of Urban Climate in Arid Lands _ Oases Effect Calculator). Based on an innovative mathematical model, we developed SPUCAL_oec as an innovative vision for this green phenomenon, programmed to predict, calculate, and simulate the behavior and limits of the palm grove on the oasis microclimate. Finally, the results of SPUCAL_oec model showed that the oasis effect impacted the oasis microclimate owing to the existence of the palm grove. This effect could be as large as 6°C of temperature decrease and 12% increase in relative humidity. Furthermore, the SPUCAL software can aid designers and planners in making decisions regarding their design process.
