Effect of the recent land use on the plant diversity and community structure of Omayed Biosphere Reserve, Egypt

Abstract

a b s t r a c tThe present study aims at describing and analysing the floristic composition and vegetation types, as well as determining the effect of recent land uses on the vegetation structure. It aims also at identifying the alien plants species and elucidating the impact of these species on the plant diversity and community structure of the study area. One hundred and ninety stands were selected monthly for this study, 145 species were recorded (69 perennials and 76 annuals) related to 83 genera, 40 families in 9 identified habitats in El-Omayed Biosphere Reserve (coastal sand dunes, salt marshes, saline depression, nonsaline depression, inland ridges, inland plateau, irrigation canals, road sides and cultivated lands). Therophytes were the most represented life form. Three habitat groups resulted after the application of TWINSPAN and DCA as classification and ordination techniques: 2 represented the natural habitats and one represented the urban and cultivated habitats. Group I represented coastal dunes and salt marshes GII: saline depressions, non-saline depressions, inland plateau and inland ridges and GIII: irrigation canals, road sides and cultivated lands. Coastal dunes had the highest species richness (α-diversity), followed by cultivated lands, while inland plateau had the lowest; but saline depressions had the highest species turnover (β-diversity). Non-saline depressions had the highest relative evenness, while saline depressions had the highest relative concentration of dominance. Coastal dunes had highest values of calcium carbonates and calcium ions, and salt marshes had the highest salinity, pH, potassium and sodium contents, but cultivated lands had the highest values of silt, clay and organic matter. The diagram resulting from CCA showed an influence of most soil variables, except nitrogen, calcium and potassium. Twenty two species were recorded for the first time in the study area. The recent land use (overgrazing, wood cutting and collecting, construction of summer resorts and irrigation canals and agricultures) led to the emergence of new invasive species, which may severely affect the plant diversity and community structure of this hot spot of biodiversity in Egypt.

The impact of five environmental factors on species distribution and weed community structure in the coastal farmland and adjacent territories in the northwest delta region, Egypt

“…Although the pioneer phytosociological and floristic studies on the Mediterranean coastal land of Egypt and Delta region date back to early of the last century (Simpson, 1932; Oliver, 1941; Tadros and Atta, 1958); but until this day the pressing need for the study of sociological relationships of weed flora in various ecological habitats continues to be debated. Although several phytosociological studies have been carried out on the Mediterranean region and Delta of Egypt, the topic of the present study has not been adequately addressed (El-Hadidi & Kosinová, 1971; Shaltout and El-Fahar, 1991; El-Demerdash et al., 1997; Mashaly et al., 2010; Shaltout and Ahmed, 2012, 2015; Abd El-Ghani et al., 2013; Ahmed et al., 2014, 2015; Mahgoub, 2017 and Abdelaal et al., 2017). Neither of them aimed to study the order of importance for the impact of the prevailing climate; soil type; crop type; crop sustainability and urbanization on species distribution and diversity of weed community.…”

Controlling factors of plant community composition with respect to the slope aspect gradient in the Qilian Mountains

“…Being mainly covered by forest and grassland, these mountains are significant carbon pools in the region (Wagner et al 2015), although this role is likely influenced by the slope aspect (Qin et al 2016, Zhu et al 2017. Therefore, a better understanding of the differences in vegetation characteristics and soil parameters due to differences in the slope aspect is important for sustainable environmental management (M aren et al 2015), conservation of biodiversity, and restoration of degraded areas (Ahmed et al 2015), especially in mountainous areas. In this study, the gap mentioned above will be addressed with the hypotheses that plant community composition changes with the slope aspect and that temperature is the main controlling factor of these changes.…”

Multiple introductions and population structure during the rapid expansion of the invasive Sahara mustard (Brassica tournefortii)

“…Sahara mustard (Brassica tournefortii; Family: Brassicaceae) is a facultative autogamous (i.e., primarily self-fertilizes but outcrossing is possible) diploid annual that is native to the Mediterranean basin and much of the Middle East into western India (Aldhebiani & Howladar, 2013;Prain, 1898;Thanos, Georghiou, Douma, & Marangaki, 1991). It is a pest species in agriculture fields in parts of its native range and Australia (Ahmed, Fawzy, Saeed, & Awad, 2015;El-Saied, El-Ghamry, Khafagi, Powell, & Bedair, 2015;Salisbury, Potter, Gurung, Mailer, & Williams, 2018), but it also has traditional dietary uses and economic value in regions where it is cultivated (Guarrera & Savo, 2016;Singh, Semwal, & Bhatt, 2015). Sahara mustard is an invasive throughout much of Australia (Chauhan, Gill, & Preston, 2006), South Africa (McGeoch, Kalwij, & Rhodes, 2009), Chile (Teillier, Prina, & Lund, 2014), and more recently, western North America (Li, Dlugosch, & Enquist, 2015).…”