We studied neglected island plant communities on rock outcrops (vegetation islands or patches) that harbor many endemic species. We assessed how the post-fire habitat conditions (factor related to habitat filtering), the patch area and substrate depth (factors related to resource availability and environmental filtering), and the patch distance (spatial factor related to dispersal limitation) shape the plant community attributes, life forms and persistence–reproduction trade-offs in a campo rupestre in the Chapada Diamantina, Brazil. Two years after a wildfire, we sampled 82 vegetation islands in two habitat conditions based on fire disturbance (burned and unburned). We verified high plant mortality caused by wildfire. All succulent and desiccation-tolerant chamaephytes died, but while the desiccation-tolerant chamaephyte recolonized burned vegetation islands by seedling recruitment, the succulent chamaephyte lack regeneration after disturbance, demonstrating their vulnerability to fire disturbances. The post-fire recovery was driven by obligate resprouters (hemicryptophytes and phanerophyte), post-fire colonizers (therophytes and phanerophytes), facultative seeders (phanerophytes), and desiccation-tolerant obligate seeders (chamaephytes). Despite the similar species richness between burned and unburned vegetation islands, the fire-habitat conditions determined changes in species composition and persistence–reproduction trade-offs. We demonstrated that random processes related to the colonization-survival and persistence–reproduction trade-offs can be a strong biotic factor shaping vegetation islands on rocky outcrops beyond environmental filtering and dispersal limitation. Our study is the first to investigate the fire effects on vegetation islands in rock outcrops and reveal the desiccation-tolerant obligate seeder as a novel post-fire regeneration strategy, that has a central role in the vegetation island community assembly.

我们研究了岩石露头（植被岛屿或斑块）上被忽视的岛屿植物群落，这些岛屿蕴藏着许多特有物种。我们评估了火灾后栖息地条件（与栖息地过滤相关的因素）、斑块面积和基质深度（与资源可用性和环境过滤相关的因素）以及斑块距离（与扩散限制相关的空间因素）如何塑造植物群落巴西 Chapada Diamantina 坎波鲁佩斯特雷的属性、生命形式和持久性与繁殖权衡。野火发生两年后，我们根据火灾干扰（烧毁和未烧毁）对两种栖息地条件下的 82 个植被岛进行了采样。我们证实野火导致植物死亡率很高。所有多肉和耐干燥的狼疮植物都死亡了，但是虽然耐干燥的狼疮植物通过补充幼苗重新在被烧毁的植被岛上繁殖，但多肉的狼疮植物在干扰后缺乏再生，这表明它们对火灾干扰的脆弱性。火灾后的恢复是由专性再发芽植物（半隐植物和显芽植物）、火灾后定殖植物（隐芽植物和显芽植物）、兼性播种者（显芽植物）和耐干燥专性播种者（狼芽植物）驱动的。尽管被烧毁和未烧毁的植被岛屿之间的物种丰富度相似，但火灾栖息地条件决定了物种组成和持久性与繁殖权衡的变化。我们证明，与殖民-生存和持久性-繁殖权衡相关的随机过程可以成为塑造岩石露头植被岛的强大生物因素，超越环境过滤和扩散限制。我们的研究首次调查了火灾对岩石露头植被岛的影响，并揭示了耐干燥专性播种机作为一种新颖的火灾后再生策略，在植被岛群落聚集中发挥着核心作用。