Skip to main content

Okkacha Hasnaoui

  • Biodiversity Journal, 12 (3): 0729-0732

    Belgacem Nouar, Benchohra Maamar, Hicham Berrabah, Mohammed Souddi, Okkacha Hasnaoui & Abdelkader Nouar
    Diversity and floristic composition of Djebel Nessara region (Tiaret -Algeria)
    https://doi.org/10.31396/Biodiv.Jour.2021.12.3.729.732

    ABSTRACT
    This work undertaken represents an phytoecological approach of Djebel Nessara vegetation (Tiaret Mountains). The floristic analysis allowed us to release a list of 119 taxa distributed in 96 genera and 35 families. Angiosperms constitute 97.47% (Monocotyledonous 21% and Dicotyledonous 76.47%) while gymnosperms represent only 2.52%. The most represented families are Asteraceae, Fabaceae and Poaceae with percentages of 19.3%, 10.9% and 9.2%, respectively. The comparison of the different biological spectra shows the importance of the therophytes to the number of 57 species with 47.9%. On the biogeographical level, we notice the predominance of Mediterranean biogeographical species with 47.1%. Shannon's biodiversity index (H) is 4.28, while Piélou's Equitability (J) is 0.89 and the Simpson's index (1-D) is 0.98. However, the Perturbation index (PI) is in the order of 61.34%.

  • Biodiversity Journal, 12 (2): 0475-0482

    Farah Bessaid, Okkacha Hasnaoui, Brahim Babali, Sid Ahmed Aouadj
    Post-fire regeneration of cork Oak and holm Oak at Tlemcen National Park (Western Algeria)
    https://doi.org/10.31396/Biodiv.Jour.2021.12.2.475.482

    ABSTRACT
    The most worrying factor in forest degradation is fire, whose outbreak and spread is favored by physical and natural conditions. Algeria, like other Mediterranean countries, is paying a high cost. It must be recognized that forest fires have become disastrous in the last decades. An average of 30,000 hectares is destroyed every year, threatening the country’s ecological balance. This study aims to identify the post-fire dynamics of forest structuring species in Tlemcen National Park (Western Algeria). This article is written in this context. This work is based on observations as well as a monitoring of burned sites. The aim is to show concretely the resilience of cork Oak (Quercus suber L.) and holm Oak (Q. ilex L.), the flagship species of Tlemcen National Park, in order to develop a conservation strategy and identify a succession model after a fire. An experimental protocol has been put in place to assess vegetation regeneration. Post-fire morphometric measurements were performed three years in a row (T1, T2 and T3) during the adequate phenological period. The observed elongations range from 22.6 cm to 17.9 cm in the first year; 46.16 cm to 36.5 cm in the second year and 95.2 cm to 67.3 cm in the third year in favour of holm Oak. Monthly and inter-year comparative analyses reveal that, under the same site conditions, holm Oak shows a better adaptability to fires than cork Oak. The various measures recorded show an elongation of 20.95% in favour of holm Oak in the first year, 20.92% in the second year and 29.30% in the third year in favour of the holm Oak. A competition for the recapture of the burnt space takes place after the fires. As for the other species, there is a self-succession where chamephytic species are the most favoured.

  • Biodiversity Journal, 11 (1): 025-034

    Sid Ahmed Aouadj, Yahia Nasrallah & Okkacha Hasnaoui
    Regional phytogeographic analysis of the flora of the Mounts of Saida (western Algeria): evaluation-restoration report
    https://doi.org/10.31396/Biodiv.Jour.2020.11.1.25.34

    ABSTRACT
    A regional floristic and phytogeographic study was conducted in the Mounts of Saida, a sub-sector of the Tell Atlas (Oran) (O3), in the western Algeria. On an area of 56.31 Km2 surveyed regularly over time during the springs and autumns from 2017 to 2019. A total of 344 taxa divided into 77 families and 223 genera, including 18 new (exogenous) for Tell Atlas (Oran) sub-sector (O3), have been inventoried. Of these 18 species, 8 belong to the phytogeographic areas of the arid (H) and hyperarid (AS) regions and 2 invasive species that reinforce and confirm theories of plant dispersal to the north and to high altitudes for adapting to climate change. The Factor Analysis of Correspondences (F.A.C) shows that species distribution is the result of local microclimates associated with the elevation; particularly, the mountains facing north receive a significant amount of humidity from the Mediterranean Sea.