Analysis of taxonomic distinctness and priority conservation areas as a basis for heritage enhancement of floristic diversity: the case of the ‘hotspot’ of the islands of Numidia (North-eastern Algeria)

Abstract

The identification of priority conservation areas (PCA) plays an important role in biodiversity conservation, but uncertainties create challenges for conservation planning. The objective was to test a method based on 'taxonomic distinctness' (TD) and to identify PCA to quantify the heritage value of a territory and establish the most appropriate conservation measures. The researchers performed a systematic and phytogeographical analysis of ten islands in northeastern Algeria, a biological hotspot with heterogeneous ecosystem types and subject to socio-economic pressures. The biological diversity represented by 223 species in these environments reflects a high rate of endemicity (13%).

Supplementary material 1 from: Hamimeche M, Véla E, Gillet F, Moulaï R (2024) Biogeography and ecology of the Algerian island flora. Plant Ecology and Evolution 157(2): 202-219. https://doi.org/10.5091/plecevo.117464

“…As already pointed out by Benhamiche-Hanifi and , the flora of Mediterranean origin is dominant on the islands of Jijel and Bejaia, and this pattern was observed on all the studied islands, where the flora is largely dominated by the Mediterranean species (Supplementary material 2). The same characteristics were observed by Hamel et al (2023) for the islands at the extreme east of the country. However, there is a westeast difference, with the Oranese islands being influenced by the western Mediterranean sub-domain, including the Ibero-Maghrebian complex, whereas the Kabyle and Numidian islands are influenced by the central Mediterranean sub-domain, including the Tyrrhenian complex Hamel et al 2023).…”

“…The same characteristics were observed by Hamel et al (2023) for the islands at the extreme east of the country. However, there is a westeast difference, with the Oranese islands being influenced by the western Mediterranean sub-domain, including the Ibero-Maghrebian complex, whereas the Kabyle and Numidian islands are influenced by the central Mediterranean sub-domain, including the Tyrrhenian complex Hamel et al 2023).…”

“…In contrast, the majority of the islets or rocks located on the Central and Eastern coasts of Algeria are very close to the continent and they are characterized by a biogeography influenced by the Kabyle sector, the Algerian-Constantinian Tell, and the Tyrrhenian microplate complex. The same phenomenon occurs in the far east, according to a preliminary analysis of recent data by Hamel et al (2023).…”

“…In the case of the Algerian and Tunisian islands, showed that a larger surface area does not necessarily mean higher richness, nor does reduced richness mean lower conservation interest, as in the case for Rachgoun Island (large but poor although of high conservation interest), and for the Islets of Garlic and Sahel (small but of high conservation interest). This dissymmetry between surface area, richness, and conservation interest is also confirmed at the extreme east of the country by Hamel et al (2023). Due to their small surface area, the Algerian islands are not considered as regional hotspots; this is mainly due to the fact that the small surface area is insufficient to allow in situ speciation (Lomolino and Weiser 2001), and consequently these sites are very poor in exclusive endemics (Triantis et al 2008).…”

The Wetlands of Northeastern Algeria (Guelma and Souk Ahras): Stakes for the Conservation of Regional Biodiversity

“…Although in-depth research has been conducted on ecosystems in these territories, such as in the forests and coastal areas of Numidia [21][22][23][24] or Fetzara lake [16], little attention has been given to temporary wetland ecosystems [19,25]. The recent discovery of new species in northeastern Algeria, uncommon on a Mediterranean scale [26][27][28][29][30], motivates this study focused on the temporary wetlands of the Souk Ahras and Guelma regions.…”