No abstract

Irresponsible human interventions, encroachment of natural habitats, and climate change negatively affect wildlife. In this study, the effects of human influence on Wadi Hagul, an unprotected area in the north of the Egyptian Eastern Desert that has recently been subjected to blatant encroachments of vegetation, were studied. The most important of these threats is the construction of the new road Al-Galala–Wadi Hagul–Zafarana. In Wadi Hagul, 80 species are reported in this study; the most represented plant families are Asteraceae (15 species) and Brassicaceae (6 species). Perennial, chamaephyte and Saharo-Arabian species were recorded in the highest percentage. Detrended canonical correspondence analysis showed that latitude, longitude, altitude, silt, sand contents, pH, and CO32− content are the factors that have the highest effect on vegetation distribution in the studied stands. Several invasive and alien species such as Euphorbia prostrata have been listed; these species typically have a negative effect on native species. The Soil Adjusted Vegetation Index (SAVI) indicated a decrease in plant cover during the study period, as compared to previous years. In 2013 and 2020, SAVI ranged from −0.02 to 0.42 and from −0.18 to 0.28, respectively. Recently, the violation and destruction of wildlife have increased, therefore, preserving it along with general biodiversity has become an urgent necessity.

Among the 70–80 species of the genus Lycium (family Solanaceae) disjunctly distributed around the world, only three are frequently distributed in different locations in Egypt. Due to the morphological similarities between these three species, there is a need for alternative tools to distinguish them. Thus, the objective of this study was to revise the taxonomic features of Lycium europaeum L., Lycium shawii Roem. & Schult., and Lycium schweinfurthii var. aschersonii (Dammer) Feinbrun in consideration of their anatomical, metabolic, molecular, and ecological characteristics. In addition to analysis of their anatomical and ecological features, DNA barcoding was performed for molecular characterization through internal transcribed spacer (ITS) sequencing and start codon targeted (SCoT) markers. Furthermore, metabolic profiling of the studied species was conducted based on gas chromatography–mass spectrometry (GC-MS). The observed anatomical features of the adaxial and abaxial epidermal layers, type of mesophyll, crystals, number of palisade and spongy layers, and the vascular system showed variations between the studied species. Beyond this, the anatomy of the leaves showed an isobilateral structure in the studied species, without distinct differences. Species were molecularly identified in terms of ITS sequences and SCoT markers. The ITS sequences were deposited in GenBank with accession numbers ON149839.1, OP597546.1, and ON521125.1 for L. europaeum L., L. shawii, and L. schweinfurthii var. aschersonii, respectively. The sequences showed variations in GC content between the studied species; this was 63.6% in L. europaeum, 61.53% in L. shawii, and 63.55% in L. schweinfurthii var. aschersonii. A total of 62 amplified fragments, including 44 polymorphic fragments with a ratio of 70.97%, were obtained in the SCoT analysis, as well as unique amplicons in L. europaeum L., shawii, and L. schweinfurthii var. aschersonii of 5, 11, and 4 fragments, respectively. Through GC-MS profiling, 38 compounds were identified with clear fluctuations in the extracts of each species. Of these, 23 were distinguishing chemicals that could help in chemical identification of the extracts of the studied species. The present study succeeds in identifying alternative clear and diverse characteristics that can be used to distinguish between L. europaeum, L. shawii, and L. schweinfurthii var. aschersonii.

A critical foundation of sustainable agriculture is to understand different agro-ecosystems components and to investigate relations between different species and environmental factors affecting their presence and expansion. The flora of Siwa Oasis agro-ecosystems was investigated and assessed. A total of 132 stands (66 in spring and another 66 in summer) were chosen to represent the study area and its soil properties during spring and summer. Cover of each species and foliage projective cover of each stand was visually estimated. Species richness, diversity and evenness were calculated for each stand. Soil analyses showed that stands could be differentiated geographically. Vegetation and soil relationships were explored using different ecological multivariate techniques. TWINSPAN classification resulted in four ecological groups in spring and four more groups in summer. DCA and DCCA clustered stands in a similar manner to the ecological groups extracted from TWINSPAN classification. Indicator species and correlated soil characteristics of each group were identified. Salinity, crop type, water availability, shade and human intervention are the major factors affecting the diversity and richness of the vegetation communities in Siwa Oasis cultivated land. Some of the species recorded are of high economic importance, highlighting a valuable opportunity to cultivate problematic soils with non-traditional crops.

This investigation was conducted on nine sites at Helwan -El Saff area, Cairo, and Giza governorates (polluted area), and three sites, in Metrabeaa village, Monofia governorate (control). This study aimed to assess the impact of wastewater irrigation on soil quality and to test the possibility of using it as an alternative for fresh water in irrigation of agricultural land. Water and soil samples were collected from El-Khashab canal (polluted water) and Al-Bagoria canal (Nile water) and cultivated land sites adjacent to them during two seasons (July 2019 and July 2020). The values of electric conductivity (EC), sodium adsorption ratio (SAR), studied cations, anions and heavy metals were significantly higher; in wastewater samples than in Nile water samples; meanwhile, the opposite was true for hydrogen ion concentration (pH), available nitrogen and phosphorus (N and P). The values of EC, Ca ++ , Na + , Cl -, SO4 --, CaCO3,organic matter (OM) and all studied heavy metals increased in soil irrigated with wastewater as compared with the soil irrigated with Nile water; meanwhile, the opposite was true for pH, Mg ++ , soluble K + , and HCO3 -. The values of contamination factor followed the order: Co ˃ Cr ˃ Zn ˃ Mn ˃ Fe ˃ Cu ˃ Pb. Moreover, the pollution load index of soil ranged from 25.81 to 16.16. The data of this research revealed that wastewater of El-Khashab canal could effectively be used as fertility source for soil, but there are some risks as heavy metals may threaten sustainable agriculture in the study area.