Seasonality and light: drivers of abundance, species richness, and diversity in the soil seed bank of a woodland savanna

Abstract

Abstract Understanding the composition of the soil seed bank, as well as the influence of seasonality and light on seed germination, is crucial for comprehending how changes in these conditions impact the recruitment of new individuals in the aboveground community, the dynamics of natural regeneration, and responses to disturbances. In this study, we investigated the effects of seasonality and light on the abundance, species richness, and diversity of the soil seed bank. The study was conducted in the woodland savanna of Glebe II, located within the Aimorés Wildlife Refuge, which is part of the Mosaic of Conservation Units of São Paulo State Savanna, in southeastern Brazil. We analyzed the soil seed bank using the seedling emergence method in both dry and rainy seasons. Soil was collected from 25 permanent plots, divided equally. One part was placed for germination in a nursery with a polyethylene screen cover, providing 14% shading (light treatment), while the other part was placed in a nursery with a polyethylene screen cover, providing 70% shading (shady treatment). Abundance, species richness, and diversity were evaluated for each season and treatment. Our results revealed greater abundance and species richness in the soil seed bank collected during the rainy season and maintained under shady treatment. In contrast, we observed greater diversity in the soil seed bank collected during the dry season and maintained under light treatment. These findings demonstrate that seasonality and light conditions have distinct effects on different attributes of the soil seed bank in the woodland savanna.