Staff member in depertment of biology - faculty of education- university of benghazi
RESEARCH, TEACHING, or OTHER INTERESTS
Agricultural and Biological Sciences, Plant Science, Environmental Science, Biotechnology
5
Scopus Publications
Scopus Publications
Effect of Aspect and Elevation on the Degree of Aggregation and the Functional Traits in Phlomis floccosa D. Don (Lamiacae) Populations Abd El‐Nasser S. Al Borki, Abdulhamid K. Alzerbi, Hanan F. Kabiel, Ahmad K. Hegazy African Journal of Ecology, 2024 Phlomis floccosa D. Don populations are distributed in different microhabitats within Al‐Akhdar mountainous landscape, in Libya. Five populations were selected for the study. Spatial relationships among individuals were investigated using the spatial point pattern analysis. Functional traits were recorded at the vegetative, flowering and fruiting stages. Seeds were collected at the dispersal stage to estimate the regeneration potential. Greater degree of aggregation was found at higher elevations on both northern and southern sides of the mountain but with different demography and traits. On the northern side, greater degree of aggregation was accompanied by absence of large adults and greater percentage of seedlings, and it was positively associated with the reproductive output, while negatively associated with the size and regeneration indices. On the southern side, greater degree of aggregation was accompanied by greater contribution of large adults and greater percentage of seedlings, and it was positively associated with the size and regeneration indices, while negatively associated with the reproductive output. On the other hand, the population in the wadi (valley) microhabitat showed coarse‐scale clumped pattern, higher values for most of the functional traits and higher contribution of seedlings but with lower facilitation offered by adults. The variations in the degree of aggregation and the functional traits trade‐offs in P. floccosa populations ensured successful survival and regeneration in the heterogeneous microhabitats. Meanwhile, stressed conditions greatly affect the survival and regeneration of the species suggesting the need for conservation measures to overcome the adverse effects of climate change.
‘Variations in phenological and functional traits in Thapsia garganica populations in Al Jebel Al Akhdar, Libya’ Abd El‐Nasser S. Al Borki, Abdulhamid K. Alzerbi, Hanan F. Kabiel, Ahmad K. Hegazy African Journal of Ecology, 2020 Abstract Thapsia garganica is a herbaceous perennial in the Apiaceae, distributed around the Mediterranean and traditionally used in North Africa as a remedy for arthritis, herpes, hair‐fall, hypertension, rheumatic, eczema and scabies. T. garganica is the source of thapsigargin: known for killing cancer cells. Seven populations were studied in sites differing in aspect and elevation within Al Jebel Al Akhdar in Libya. We studied the within‐population size distribution of individuals, the timing of the phenological events, and vegetative and reproductive traits. Thapsia garganica showed high flexibility of functional traits and shifts in the timing of phenological events in response to elevation and aspect (north‐ or south‐facing slopes). Local soil properties, together with effects due to altitude and aspect, could be direct causes of the observed differences in terms of population size and phenological traits. The phenological patterns detected also provide insights into the species response to climate change. Despite this phenotypic flexibility, and good growth in sites at 300–700 m a. s. l. on south‐facing slopes, most sites in this study have an unstable size‐structure, with few small individuals. This raises concerns about the long‐term persistence of the other populations of this species in Al Jebel Al Akhdar.
Ecological assessment of populations of Juniperus phoenicea L. in the Al-Akhdar mountainous landscape of Libya Hanan F. Kabiel, Ahmad K. Hegazy, Lesley Lovett-Doust, Saud L. Al-Rowaily, Abd El-Nasser S. Al Borki Arid Land Research and Management, 2016 The Phoenician juniper (Juniperus phoenicea L.) has long been common in the Al-Akhdar mountain range in NE Libya. Juniper trees in the region are showing signs of dieback, and minimal successful seedling recruitment has occurred. We investigate this effect at the level of individual trees, tree size classes, and populations. At ten sites, population size, growth and reproductive traits, and percentage dieback in different size classes were evaluated. Elevation, distance from the sea, and the interaction between these factors had a significant effect on tree volume, and number of branches, number of female cones per branch and number of female cones per tree. Two groups of populations were recognized: the first (Sites 2, 3, and 4) were near the coast. They appeared to be more recently established, with no individuals in the largest size class, and, at this point, less severe dieback. In contrast, in the rest of the sites there were no individuals (Sites 1, 5, 6, and 9) or very few individuals (Sites 7, 8, and 10) in the smallest size class, indicating widespread failure of recruitment in recent years. Mature female cones containing seeds were abundant at these sites (except for Site 8); therefore, this was not attributable to failure of sexual reproduction, but rather was associated with higher levels of intra- and inter-specific competition, combined with more variable rainfall in recent years. Smaller trees are particularly susceptible to dieback throughout the region. Conservation initiatives should include restrictions on clearing these natural forests for conversion to agriculture and, where harvesting is necessary, preferential harvesting of larger individuals.
