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Many studies have examined the morphological and micromorphological responses of different halophytes to determine their salt tolerance mechanisms. However, few studies have focused on the South African edible halophytes. This study examined the leaf micromorphology, elemental composition, and anatomical responses using scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX) to examine salt tolerance levels in Trachyandra ciliata (L.F) Kunth. The treatments included varying sodium chloride (NaCl) concentrations: 50 mM, 100 mM, 150 mM and 200 mM, while control (0 mM) was watered with nutrient solution only. From the SEM micrographs, salt glands were observed protruding from the epidermis along the vascular system under low salinity and salt crystals appeared under higher concentrations, which makes this plant maintain cellular homeostasis under high salinity, and the plant can be classified as a recretohalophyte. Stomatal distribution, stomatal density and the number of open stomata decreased with increasing salinity. EDX revealed the presence of some important elements such as potassium, magnesium, phosphorus, calcium and more in the leaves. The results showed that increased salinity led to a decrease in the percentage composition of P, K and Ca2+, while Mg2+ was high under the control and low salinity (50 mM), decreased under 100 mM and increased again with increasing salinity. On the contrary, increasing salinity caused an increase in Na+ and Cl- in a stable manner. These findings reveal that T.ciliata acquires salt tolerance through changes to its leaf surface properties, osmotic adjustment, and the regulation of Na+ uptake and distribution in the leaves. [ABSTRACT FROM AUTHOR]

Groundwater is vital for sustainable development, and this study addresses potable water challenges in Shango, North-Central Nigeria. The main goal is to identify optimal sites for new wells and boreholes, utilizing geological and geo-electrical attributes from existing boreholes and wells. Vertical Electrical Sounding (VES) assessed groundwater potential, aquifer protection, and overburden corrosivity. Sixteen VES stations were probed using Schlumberger array with a maximum current electrode spacing (AB/2) of 200 m using a resistivity meter. The data were interpreted using an automatic computer inversion program, IPI2WIN. The VES results revealed five subsurface geo-electric units, with depths to the aquifer ranging from 58 to 68 m, each exhibiting distinct characteristics contributing to the lithological variability of the research area. Hydraulic conductivity ranged from 0.465 to 0.534 m/day, while transmissivity varied from 9.589 m2/day to 26.029 m2/day across different VES points. Regions exhibiting thick layers and low resistivity values indicate high longitudinal conductivity. Furthermore, areas with low protective capacity are susceptible to the risks of pollution and contamination stemming from leaks and waste sites. The study revealed that all VES points are in practically non-corrosive zones, making them suitable for burying underground tanks with extremely low deterioration rates. Based on geoelectrical characteristics, the study area was divided into three groundwater potential zones: low, medium, and high. These findings provide valuable insights into the groundwater potential and protective capacity of the Shango area, while emphasizing on the vulnerability of these regions and highlighting the pressing need for appropriate preventive measures to safeguard against potential environmental hazards. [ABSTRACT FROM AUTHOR]

Tetragonia decumbens Mill. has recently been reported to withstand the adverse effect of salinity. However, its leaf anatomical responses are poorly understood since previous studies were focused on basic physiological and biochemical parameters. This study was designed to examine leaf micromorphological traits and internal leaf elemental compartmentalization using Scanning Electron Microscopy (SEM) and Energy Dispersive X-Ray (EDX) to elucidate relative salinity tolerance mechanisms. Salt concentrations were applied to six treatments by increasing the concentrations of NaCl in a nutrient solution. The control treatment (0 mM) was irrigated solely by the nutritional solution, whereas other treatments contained graded NaCl concentrations (50, 100, 150, 200, and 250 mM). Micromorphological examination of the adaxial layer of the epidermis revealed distinctive glandular peltate trichomes among treatments. In control plants, the trichomes were flaccid and not easily detectable which resulted in low trichome density. While plants treated with salinity had uprooted trichomes which were modified to dish-like structures as salinity increases, with a more pronounce visibility at the highest salinity treatment (250 mM). On the contrary, increasing salinity reduced the stomatal density as well as stomatal opening with a more pronounced effect at 250 mM. Furthermore, the EDX revealed the presence of important elements such as potassium (K), calcium (Ca), magnesium (Mg), sodium (Na) and chlorine (Cl) which are responsible for salt tolerance in many species. Na increased with increasing saline treatment up to 100 mM then declined drastically. The lowest Na was detected in control plants which were comparable to plants irrigated with 150, 200 and 250 mM respectively. Likewise, the lowest chlorine content was detected in control plants while it increased in saline treated plants up to 150 mM and declined in plants irrigated with 200 and 250 mM respectively. When assessing K quantification, saline treatment drastically reduced K content with increasing saline irrigation. Contrariwise, the Mg content increased with saline irrigation up to 100 mM and was not detected in plants irrigated with 200 and 250 mM respectively. Interestingly, Ca was only detected in plants irrigated with 150, 200 and 250 mM respectively. These findings validate that T. decumbens can tolerate salinity by modulating anatomical features such as trichomes, control of stomatal aperture and effectively managing ion toxicity with increasing salinity. [ABSTRACT FROM AUTHOR]