The soil seed bank is crucial for the stability and regeneration of the specialised gypsum plant communities. The presence of shrubs influences the spatial structure of the soil seed bank by trapping more or fewer seeds depending on their physiognomic attributes or, for example, by providing seeds through the plants established under canopies. We aimed to unravel the potential role of different shrub species with diverse physiognomy in determining the spatial structure of the soil seed bank in a semi-arid gypsum plant community of NE Spain. We examined richness and abundance of the soil seed bank at different microsites associated with four dominant shrubs of different size-type (tall or short), and architecture (crawling-branched or erect). We found more considerable richness and abundance of seeds of perennial species within shrub canopies than in open areas. Specifically, the crawling-branched shrubs Gypsophila struthium and Helianthemum squamatum, and the tall erect shrub Ononis tridentata accumulated the most abundant soil seed banks of perennials, thus having an important structuring role. Conservation and restoration efforts should focus on gypsophyte shrubs (G. struthium, O. tridentata and H. squamatum), which can enhance community stability and regeneration through the formation of an abundant soil seed bank of perennial species in gypsum plant communities.

土壤种子库对于专业石膏植物群落的稳定性和再生至关重要。灌木的存在通过根据其生理特征捕获或多或少的种子，或例如通过在冠层下建立的植物提供种子，来影响土壤种子库的空间结构。我们旨在揭示具有不同相貌的不同灌木物种在确定西班牙东北半干旱石膏植物群落中土壤种子库空间结构方面的潜在作用。我们研究了与四个不同大小类型（高或矮）和结构（爬行分支或直立）的优势灌木相关的不同地点的土壤种子库的丰富度和丰度。我们发现灌木林冠层中多年生物种种子的丰度和丰度要比空旷地区高得多。具体而言，爬行分支的灌木满天星struthium和半日squamatum，和高大直立灌木芒柄花三齿积累多年生植物最丰富的土壤种子库，因此具有重要的结构作用。保护和恢复工作应着重于石膏植物灌木（G. struthium，O。tridentata和H. squamatum），这可以通过在石膏植物群落中形成多年生物种丰富的土壤种子库来增强群落稳定性和再生。