Uncovering hidden biodiversity through the role of soil seed banks in conserving arid wadis

Abstract Arid desert ecosystems harbor unique plant communities that are highly adapted to harsh environmental conditions but are increasingly threatened by human activities and climate change. Understanding the composition and dynamics of these ecosystems is crucial for effective conservation. In the Ataqa region, the native flora of four unprotected arid wadis is under threat. These wadis are Wadi Hagul, Wadi El-Bada, Wadi El-Gamil, and Wadi Amlog. The main threats include vegetation over-collection, resort development, quarrying, industrial expansion, road construction, and climate change. This study underscores the vital role of soil seed banks as biodiversity reservoirs that enhance ecosystem resilience and aid in conserving native and rare plant species under such pressures. Between 2023 and 2024, fieldwork was conducted to collect plant specimens and soil samples, enabling a comparative analysis of above-ground vegetation and soil seed banks. A total of 41 species were identified in the soil seed bank, comprising 31 flowering plants and 10 bryophytes. However, only 12 of these species were also found in the above-ground flora. The families Asteraceae, Caryophyllaceae, and Poaceae were the most represented in the seed bank, with therophytes emerging as the dominant life form. TWINSPAN classification revealed five distinct plant assemblages, with Bryum argenteum , Tamarix nilotica , Zygophyllum coccineum , and Spergularia diandra as dominant species. Environmental parameters particularly electrical conductivity, pH, and calcium carbonate content were key drivers influencing the distribution patterns of above-ground vegetation. Notably, the seed bank contained several species not recorded in the existing flora of the region, including Chenopodium vulvaria , Juncus fontanesii , and Riccia congoana . This suggests that the seed bank serves as a reservoir for rare and cryptic species. These findings have important implications for ecological restoration and the conservation of biodiversity in arid environments under anthropogenic and climatic pressures.