Equations d'Estimation de la Phytomasse Aerienne des Plantes Spontanees Perennes Broutees par le Dromadaire au Sahara Nord-Occidental Algerien = Prediction Equation for Determining the Phytomass of Spontaneous Perennial Plants Grazed by the Dromedary in the North Western Sahara of Algeria

2015 ◽  
Vol 5 (1) ◽  
pp. 29-36
Author(s):  
M. Bouallala ◽  
A. Chehma
Keyword(s):  
Prediction Equation ◽  
Western Sahara ◽  
Perennial Plants ◽  
The North ◽  
North Western

scholarly journals A GIS-Based Approach to Inform Agriculture-Water-Energy Nexus Planning in the North Western Sahara Aquifer System (NWSAS)

2020 ◽  
Vol 12 (17) ◽  
pp. 7043 ◽  
Author(s):  
Youssef Almulla ◽  
Camilo Ramirez ◽  
Konstantinos Pegios ◽  
Alexandros Korkovelos ◽  
Lucia de Strasser ◽  
...  
Keyword(s):  
Fossil Fuels ◽  
Mathematical Formulation ◽  
Western Sahara ◽  
Aquifer System ◽  
Water Abstraction ◽  
The North ◽  
Groundwater Source ◽  
Water Scarce ◽  
North Western ◽  
Agriculture Water

The North Western Sahara Aquifer System (NWSAS) is a vital groundwater source in a notably water-scarce region. However, impetuous agricultural expansion and poor resource management (e.g., over-irrigation, inefficient techniques) over the past decades have raised a number of challenges. In this exploratory study, we introduce an open access GIS-based model to help answer selected timely questions related to the agriculture, water and energy nexus in the region. First, the model uses spatial and tabular data to identify the location and extent of irrigated cropland. Then, it employs spatially explicit climatic datasets and mathematical formulation to estimate water and electricity requirements for groundwater irrigation in all identified locations. Finally, it evaluates selected supply options to meet the electricity demand and suggests the least-cost configuration in each location. Results indicate that full irrigation in the basin requires ~3.25 billion million m3 per year. This translates to ~730 GWh of electricity. Fossil fuels do provide the least-cost electricity supply option due to lower capital and subsidized operating costs. Hence, to improve the competitiveness of renewable technologies (RT) (i.e., solar), a support scheme to drop the capital cost of RTs is critically needed. Finally, moving towards drip irrigation can lead to ~47% of water abstraction savings in the NWSAS area.

The conflict in Western Sahara – an unresolved issue from the decolonization period

2002 ◽  
Vol 5 ◽  
pp. 375-380 ◽  
Author(s):  
Hans-Peter Gasser
Keyword(s):  
Atlantic Coast ◽  
Small Towns ◽  
Sahara Desert ◽  
Unresolved Issue ◽  
African Continent ◽  
Western Sahara ◽  
North West ◽  
The North ◽  
North Western ◽  
Phosphate Deposits

The territory of Western Sahara has an area of about 280,000 sq. km and approximately 250,000 inhabitants, known as Sahrawis. It is situated in the north-west of the African continent, where the Sahara Desert meets the Atlantic Ocean, and has a coastline of more than 1,000 km. In the north, Western Sahara has a common border of 443 km with Morocco, and in the south and west it is bordered by Mauritania (1,561 km). The territory also has a short common border of 42 km with Algeria. The climate is predominantly that of the desert: hot and dry in summer, cold in winter, with little or no rainfall. In the coastal regions vegetation may be abundant. While the Sahrawis were originally nomads, most of the population now lives in small towns and villages. The economy is based on agriculture and fishing, primarily destined for local consumption. Rich phosphate deposits are the main export commodity. There seem to be oil deposits off the Atlantic coast.

Revisiting recharge and sustainability of the North-Western Sahara aquifers

2020 ◽  
Vol 20 (2) ◽  
Author(s):  
Julio Gonçalvès ◽  
Pierre Deschamps ◽  
Bruno Hamelin ◽  
Christine Vallet-Coulomb ◽  
Jade Petersen ◽  
...  
Keyword(s):  
Western Sahara ◽  
The North ◽  
North Western

scholarly journals Evaluating methods for surveying the Endangered Cuvier's gazelleGazella cuvieriin arid landscapes

Oryx ◽  
2016 ◽  
Vol 51 (4) ◽  
pp. 648-655 ◽  
Author(s):  
Jose María Gil-Sánchez ◽  
F. Javier Herrera-Sánchez ◽  
Begoña Álvarez ◽  
Ángel Arredondo ◽  
Jesús Bautista ◽  
...  
Keyword(s):  
Distance Sampling ◽  
Population Monitoring ◽  
Arid Environments ◽  
Occupancy Modelling ◽  
Field Methods ◽  
Western Sahara ◽  
Western Africa ◽  
The North ◽  
Indirect Sign ◽  
North Western

AbstractThe Endangered Cuvier's gazelleGazella cuvieriis an endemic ungulate of north-western Africa. Information on the species has been based primarily on non-systematic surveys, and the corresponding status estimates are of unknown quality. We evaluate the effectiveness and efficiency of two field methods for systematic surveys of populations of Cuvier's gazelle in arid environments: distance sampling (based on sightings) and sampling indirect sign (tracks and scats). The work was carried out in the north-western Sahara Desert, in Morocco, where what is possibly the largest population of Cuvier's gazelle persists. A logistically viable survey was conducted over a total area of c. 20.000 km2in 10 expeditions during 2011–2014. A total of 67 sites were surveyed, with 194 walking surveys (2,169 km in total). Gazelle signs were detected at 50 sites, and gazelles were sighted at 21 sites (61 individuals). We found a relationship between sightings and abundance indices based on indirect sign, which could be useful for population monitoring or ecological studies. Additionally, the data could be used in occupancy modelling. Density estimates based on distance sampling required considerable effort; however, it is possible to survey large areas during relatively short campaigns, and this proved to be the most useful approach to obtain data on the demographic structure of the population.

Barriers for conservation: mitigating the impact on amphibians and reptiles by water cisterns in arid environments

2017 ◽  
Vol 38 (1) ◽  
pp. 113-118 ◽  
Author(s):  
Juan M. Pleguezuelos ◽  
Luis García-Cardenete ◽  
Jesús Caro ◽  
Mónica Feriche ◽  
María T. Pérez-García ◽  
...  
Keyword(s):  
Mixed Models ◽  
Cost Effective ◽  
Wire Mesh ◽  
Arid Environments ◽  
Western Sahara ◽  
The North ◽  
Management Condition ◽  
Conservation Concern ◽  
The Impact ◽  
North Western

Anthropogenic infrastructures are one of the major threats to biodiversity. In the north-western Sahara shepherds are increasingly building water cisterns of reinforced concrete for watering livestock. These infrastructures attract desert fauna and act as indiscriminate death traps for the amphibians and reptiles (herps) in the surrounding habitats. Here we propose an on-site, cost-effective management measure. We selected two groups of 36 cisterns, managed a group by covering the lateral openings with wire mesh (managed cistern), leaving the other group unmanaged (control cistern). Managed cisterns trapped fewer species, fewer individuals (one third), and individuals of smaller body size and of less conservation concern than did control cisterns. In a multivariate approach by Generalized Mixed Models, the best models explaining the number of species and individuals of herps trapped within cisterns included as the predictor only the management condition, with a trend for higher values in control cisterns.

Sign in / Sign up

Export Citation Format

Share Document