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BackgroundEthnobotanical research studies in Jordan mostly targeted the medicinal uses of plants ignoring the other important uses. Comprehensive documentation of traditional knowledge of using native plants in the delicate desert ecosystem is very crucial for prioritizing biodiversity conservation and socio-economic improvement programs. This study therefore documents and analyzes the traditional knowledge of native plants used for grazing, firewood, food, and medicine by local inhabitants of the southern part of Wadi Araba desert in southwest Jordan. MethodsThe information was obtained using a structured survey targeting 296 informants inhabiting the southern part of Wadi Araba. The documented data was quantitively analyzed by calculating the frequency of citation for the uses categories and species used. ResultsThe results showed that the most important species used as a source of feed for the grazing animals and for firewood is Haloxylon persicum, which also indicates that the species is under overexploitation stress. About 91% of the informants mentioned that they collect plants for medicinal uses compared to 7% who collect them for food, and 6.4% of the informants mentioned that they get the plants from their families and they rarely cultivate them. The informants attributed the reduction in vegetation cover to the lack of water and overgrazing. Whereas, firewood scarcity and long distance to the grazing and wood cutting sites are the most obstacles that face firewood collection. ConclusionOur study concluded that the local people of the study area are still interested in the utilization of the native plants in their surroundings as their ancestors did. Yet, there is some pressure on certain plant species and certain geographic areas that conservation and development programs should take into consideration. This information obtained in this study is interesting for economic improvement and biodiversity conservation programs in adopting small businesses that cultivate the most collected plants to reduce pressure on the ecosystem and to generate income for local families.

Horizontally curved bridges have been mostly built with steel plate I-girders or tub girders. In the past 15 years, curved concrete girders have been successfully used in several states, including Nebraska, Colorado, and Flor­ida. This paper addresses the design of curved concrete girder bridges using ultra-high-performance concrete (UHPC) by combining state-of-the-art spliced girder technology and UHPC technology. It also proposes a number of unique features that result in further simplifi­cation of precast concrete production and construction. Critical design criteria are discussed. The system devel­opment of curved UHPC girder bridges and necessary construction steps are elaborated through a numerical example of a three-span bridge, which shows greatly reduced concrete quantities when compared with re­cently constructed curved concrete girders. With UHPC designed as proposed here, horizontally curved bridges are expected to be cost competitive with conventional concrete and more economical than structural steel.

Wastewater is actively used for irrigation of vegetable and forage crops in arid lands due to water scarcity and cost advantages. The objective of this review was to assess the effect of wastewater (mixture sources) reuse in irrigation on soil, crop (vegetable and forage crops), animal products, and human health. The metadata analysis of 95 studies revealed that the mean of toxic heavy metals including nickel (Ni), chromium (Cr), cadmium (Cd), lead (Pb), and zinc (Zn) in untreated wastewater were higher than the world standard limits in wastewater-irrigated regions. Although heavy metals in treated wastewater were within the standard limits in those areas, the concentration of those toxic elements (Pb, Cd, Ni, Cr, and As) exceeded the allowable limits in both soil and vegetables’ edible parts. In fact, the concentration of heavy metals in vegetables’ edible parts increased by 3–9 fold when compared with those irrigated with fresh water. Escherichia coli in wastewater-irrigated soil was about 2 × 106 (CFU g−1) and about 15 (CFU g−1) in vegetables’ edible parts (leaf, bulb, tuber and fruit) while the mean total coliforms was about 1.4 × 106 and 55 (CFU g−1) in soil and vegetables’ edible parts, respectively. For human health risk assessment, the estimated daily intake (EDI) and human health risk index (HRI) ranged from 0.01 to 8 (EDI and HRI > 1.0 associated with adverse health effects). Although the mean of EDI for heavy metals from wastewater-irrigated vegetables were less than 1, the HRI for Cd and Pb were above the limits for safe consumption. Overall, heavy metal levels in wastewater that used for irrigation of agricultural crops could be within the recommended levels by the world standards, but the long-term use of this reused water will contaminate soil and crops with several toxic heavy metals leading to potential carcinogenic risks to humans. Therefore, rigorous and frequent testing (wastewater, soil, and plant) is required in cultivated farms to prevent the translocation of heavy metals in the food chain.

Mise en evidence des proprietes mesomorphes de l'oleate de triethanolammonium. Determination par diffraction RX de la distance intercouche. Spectre IR

Mise en evidence des proprietes mesomorphes de l'oleate de triethanolammonium. Determination par diffraction RX de la distance intercouche. Spectre IR