La banca dei semi del suolo dei cedui di cerro a regime e abbandonati: risultati di uno studio sperimentale in Val di Cecina (Toscana)

The soil seed bank is a key component in the dynamic processes of many ter - restrial ecosystems. It consists of a reserve of viable spermatophyte seeds stored in the soil for variable periods, potentially lasting several decades. In forest environments, the seed bank serves as an important mechanism of resilience, playing a crucial role in vegetation recovery following both natural regeneration processes and disturbances. Additionally, it acts as a hidden reservoir of plant diversity, often preserving traces of past vegetation. Despite its ecological importance, many characteristics and processes of the seed bank remain poorly understood, particularly in Mediterranean forests and in relation to forest management. To help fill these knowledge gaps, we analyzed the soil seed bank of two supra-Mediterranean turkey oak-dominated forests in the Val di Cecina (central-western Tuscany), which are similar in site conditions but differ in management regimes: the former is actively managed as a coppice- with-standards, while the latter has been abandoned for over 60 years. Seed bank density and composition were assessed through a germination experiment, in which 24 soil samples (12 per management type) were placed in a greenhouse under uniform conditions of temperature, light, and humidity, promoting germination of all viable seeds. The herb layer vegetation was surveyed to compare species richness and composition with that of the seed bank. The obtained data were analyzed using statistical tests and principal component analysis (PCA) to evaluate differences in floristic structure, diversity, and ecological-functional profiles attributable to management practices. Our results show that coppicing promotes a richer and more abundant seed bank, dominated by generalist and ruderal species. In contrast, abandoned stands host a greater proportion of forest specialists and Mediterranean taxa. The presence of species lacking from the current vegetation highlights the role of the seed bank as an “ecological memory”, capable of preserving latent species and potentially crucial for ecosystem resilience. Finally, the observed floristic homogeneity among seed banks, compared to the greater variability in the standing vegetation, suggests a filtering effect driven by seed persistence, which contributes to compositional stability across different management regimes.