Invasive species have been considered as one of the most serious threats to the biodiversity of various ecosystems, particularly in arid regions. The present study aimed to assess the influence of the invasive shrub Nicotiana glauca on the biodiversity of different habitats in Taif region, Saudi Arabia as well as to determine the highest habitat with seed bank of N. glauca. Soil samples were collected from three locations (Alwaht, Ash-shafa, and Ar Ruddaf), invaded with N. glauca, and analyzed for the soil seed bank. A soil seed experiment was designed in a greenhouse, whereby emerged plant seedlings were left to grow for three months and identified as well as the species density and biodiversity were assessed under and outside the canopy of N. glauca. Also, the floristic composition, life forms, and chorotype spectra of the plant species of the seed bank were analyzed. A total of 42 species, belonging to 23 families, were recorded in the soil seed bank. Asteraceae, Poaceae, and Cyperaceae were the major families (42.9%). The life form spectra of the recorded species were dominated by Therophytes (59.5%). Chorotype spectra analysis revealed that Mediterranean, Saharo-Arabian, and Irano-Turanian were the most represented elements. The species richness and evenness were higher outside the canopy, which indicates a negative effect of the invasive shrub N. glauca on the plant biodiversity in the study area, particularly in Ar Ruddaf location. This could be attributed to the competition or allelopathic effect of N. glauca. In contrast, the density of N. glauca seeds was higher under the canopy compared to outside. The soil nutrients and moisture under the canopy were higher than outside canopy. The present study provides a deeper understanding of the most susceptible habitats or communities to the invasion by N. glauca and thereby open the challenge toward control of this noxious plant and vegetation restoration.

入侵物种被认为是对各种生态系统生物多样性最严重的威胁之一，特别是在干旱地区。本研究旨在评估入侵灌木青花烟草对沙特阿拉伯塔伊夫地区不同生境生物多样性的影响，并确定青花烟草种子库的最高栖息地。从三个地点（Alwaht、Ash-shafa 和 Ar Ruddaf）收集了青绿猪笼草入侵的土壤样本，并分析了土壤种子库。在温室中设计了土壤种子实验，使出土的植物幼苗生长三个月并进行鉴定，并评估青冠猪笼草冠层内外的物种密度和生物多样性。此外，还分析了种子库植物的区系组成、生活型和脉型谱。土壤种子库共记录23科42种。主要科为菊科、禾本科、莎草科（42.9%）。记录物种的生命型谱以Therophytes为主（59.5%）。脉型光谱分析显示，地中海、撒哈罗-阿拉伯和伊朗-图兰是最具代表性的元素。树冠外的物种丰富度和均匀度较高，这表明入侵灌木N. glauca对研究区，特别是 Ar Ruddaf 地区的植物生物多样性产生了负面影响。这可能归因于青花猪笼草的竞争或化感作用。相比之下，冠层下青花猪笼草种子的密度比外部更高。冠层下土壤养分和水分均高于冠层外。本研究提供了对最容易受到青绿猪笼草入侵的栖息地或群落的更深入的了解，从而对控制这种有毒植物和植被恢复提出了挑战。