West Saudi Arabia Research Articles

Meteorological impact assessment of possible large scale irrigation in Southwest Saudi Arabia

On continental to regional scales feedbacks between landuse and landcover change and climate have been widely documented over the past 10–15 years. In the present study we explore the possibility that also vegetation changes over much smaller areas may affect local precipitation regimes. Large scale (∼ 10 5 ha) irrigated plantations in semi-arid environments under particular conditions may affect local circulations and induce additional rainfall. Capturing this rainfall ‘surplus’ could then reduce the need for external irrigation sources and eventually lead to self-sustained water cycling. This concept is studied in the coastal plains in South West Saudi Arabia where the mountains of the Asir region exhibit the highest rainfall of the peninsula due to orographic lifting and condensation of moisture imported with the Indian Ocean monsoon and with disturbances from the Mediterranean Sea. We use a regional atmospheric modeling system (RAMS) forced by ECMWF analysis data to resolve the effect of complex surface conditions in high resolution (Δ x = 4 km). After validation, these simulations are analysed with a focus on the role of local processes (sea breezes, orographic lifting and the formation of fog in the coastal mountains) in generating rainfall, and on how these will be affected by large scale irrigated plantations in the coastal desert. The validation showed that the model simulates the regional and local weather reasonably well. The simulations exhibit a slightly larger diurnal temperature range than those captured by the observations, but seem to capture daily sea-breeze phenomena well. Monthly rainfall is well reproduced at coarse resolutions, but appears more localized at high resolutions. The hypothetical irrigated plantation (3.25 10 5 ha) has significant effects on atmospheric moisture, but due to weakened sea breezes this leads to limited increases of rainfall. In terms of recycling of irrigation gifts the rainfall enhancement in this particular setting is rather insignificant.

A serologic survey of wild felids from central west Saudi Arabia.

Forty-five wildcats (Felis silvestris), 17 sand cats (Felis margarita), and 17 feral domestic cats were captured in central west Saudi Arabia, between May 1998 and April 2000, with the aim to assess their exposure to feline immunodeficiency virus/puma lentivirus (FIV/PLV), feline leukaemia virus (FeLV), feline herpesvirus (FHV-1), feline calicivirus (FCV), feline coronavirus (FCoV), and feline panleukopenia virus (FPLV). Serologic prevalence in wildcats, sand cats, and feral domestic cats were respectively: 6%, 0%, 8% for FIV/PLV; 3%, 8%, 0% for FeLV; 5%, 0%, 15% for FHV-1; 25%, 0%, 39% for FCV; 10%, 0%, 0% for FCoV; and 5%, 0%, 8% for FPLV. We recorded the first case of FeLV antigenemia in a wild sand cat. Positive results to FIV/PLV in wildcats and feral cats confirmed the occurrence of a feline lentivirus in the sampled population.

Floristic Composition and Vegetation of Wadi Talha, Aseer Mountains, South West Saudi Arabia

Floristic Composition and Vegetation of Wadi Talha, Aseer Mountains, South West Saudi Arabia

Risk Factors for Sexually Transmitted Diseases among Patients Attending Dermatovenereology Clinics in Al-Taif, West Saudi Arabia

Risk Factors for Sexually Transmitted Diseases among Patients Attending Dermatovenereology Clinics in Al-Taif, West Saudi Arabia

GROWTH AND ENERGY CONTENT OF THREE FORAGE GRASSES FROM THE MIDDLE EAST RANGELANDS

This study was conducted on three naturally growing populations of the perennial grasses Panicum turgidum Forssk, Lasiurus scindicus Henrard and Pennisetum divisum Henrard in Egypt, south west Saudi Arabia and Qatar. Vegetative reproduction occurs by rhizome growth and sexual reproduction by tillering, where each tiller may end with a spike. The failure of sexual reproduction is mainly related to the extremely arid conditions and the overgrazing of flowering branches or seeds before dispersal. Phenological behaviour varied among species and differed within the same species in the three study areas. The earliness/lateness and narrow/wide spectrum of the active phenological phases (vegetative growth, flowering and fruiting) were species-dependent rather than locality-dependent. The phenophases of the three species in Saudi Arabia and Qatar proceeded at a faster rate than in Egypt. The plants collected from Saudi Arabia and Egypt attained higher energy content than those collected from Qatar. The overall energy content of P. turgidum (over 6 kcal. g -1 dry weight) is higher than that of L. scindicus and P. divisum (less than 6 kcal. g -1 dry weight). During the peak flowering/fruiting time, the fruits and rhizomes of the three species showed higher energy content than the roots and shoots. When the growth characteristics and energy content were taken as a measure of the grazing value, P. turgidum had better value as a forage plant than the other two species.

A Method Of Estimating Design Flood Hydrograph Shape In An Arid Region

ABSTRACT Unithydrograph techniques developed for design hydrographs in temperates wnes do not work well for arid zones. This is mainly attributed to the cellular nature of rainfall invalidating unit hydrograph theory. A technique is required that yields hydrograph shapes that are consistent with those measured in arid zones. A methodology has been developed that provides hydrograph shapes for catchment sizes ranging from 170 to 2672 km2. The method is based on analyses of 32 flood hydrographs in south west Saudi Arabia. The method, however, must be used concurrently with estimates of peak discharge obtained from regional studies.

Mountain Farmer and Fellah in Asir South West Saudi Arabia: The Conditions of Agriculture in a Traditional Society

Mountain Farmer and Fellah in Asir South West Saudi Arabia: The Conditions of Agriculture in a Traditional Society