Characterization of the wild plants in Wadi Degla Protectorate, North Eastern Desert, Egypt

The present study aimed to evaluate the floristic characteristics of the wild plants in Wadi Degla Protectorate, including taxonomic diversity, life and sex forms, dispersal types, economic potential, threats, and national and global floristic distributions. Field visits were conducted during January and April (2021), and the study area was divided to 185 locations to comprise all the Wadi. From each location, plant and seed specimens were collected. In the present study, 161 plants belonged to 128 genera, and 43 families were recorded. They inhabited three habitats (upstream, midstream, and downstream). Therophytes were the most represented life form. Bisexuals were the most represented sex form. Sarcochores were the most represented dispersal type, followed by desmochores. For small geographic range - national habitat - non-abundant plants were the most represented rarity form. For national scales, the Mediterranean and Sinai regions were the richest wild plants. For global scales, the Saharo-Sindian and Mediterranean regions were the most represented elements. Medicinal plants were the most represented good, while solid wastes were the most represented threat.

Potential implementation of trees to remediate contaminated soil in Egypt

Soil and water in Egypt have become contaminated with multiple pollutants. These contaminants arise from diverse sources, including misuse of fertilizers, industrial effluent discharged into irrigation water, discharge of wastewater in rural areas, and mining activities discharging wet and dry atmospheric deposits and heavy metal contamination. The pollutants can directly affect the quality of air, water, and food and have an adverse effect on human health. About 33% of the cultivated lands in Egypt are salinized due to extreme conditions like high temperatures and aridity. The presence of elevated salt levels in the soil leads to grave consequences for seed germination, plant biochemical processes, development, and reproduction, all of which result in the output of reactive oxygen species and eventually plant death. Despite the possibility of thermal, chemical, or a combination of the two to remediate contaminated soils, their applications are complicated and costly. Some plants, called hyperaccumulators, exhibit the potential to clean up pollutants safely from the soil and water at a low cost. All the technologies used in soil decontamination are called phytoremediation. Some physiological (e.g., phytoextraction, phytostabilization, phytotransformation, rhizofiltration, phytostimulation, phytovolatilization, phytodegradation, and phytodesalination) and molecular parameters (e.g., genes, peptides, and proteins) are involved in heavy metals accumulation of these plants. Although trees are not classified as hyperaccumulators, they have recently proved higher phytoremediation potential than herbaceous plants due to their deeper root system and greater biomass growth. Indeed, this review sheds the light on the application of trees for the phytoremediation of salts and heavy metals in Egypt.