Format: ORAL

Rossano Bolpagni

Department of Chemistry, Life Sciences and Environmental Sustainabilty, University of Parma, Parma, IT

Freshwater biodiversity is collapsing globally. Urgent and effective actions are essential to address this crisis within-a-crisis. In Europe, for example, most up-to-date data show that climate change is a growing threat (1), mainly due to increased drought and decreased precipitation, while agricultural activities, land abandonment and urbanization (2) are the main pressures on habitats and species of conservation concern. Natural wetlands emerge as the best sites for preserving adequate levels of aquatic and riparian vegetation and associated biota; however, especially in the lowlands, pristine wetlands and aquatic ecosystems have almost completely disappeared. Therefore, actions are needed to maintain, on the one hand, and recreate, on the other hand, an extensive network of wetlands capable of preserving acceptable levels of aquatic/wetland vegetation diversity and functioning. Understanding the eco-functional responses of macrophytes to ecological/anthropogenic pressures and local effects of the climate crisis is, then, crucial to achieving this fundamental goal. Findings gathered over the past two decades on diverse and complex wetland systems located in overexploited Italian lowlands confirm the key contribution made by natural sites in maintaining vegetation diversity in highly compromised riverine settings. This also suggests a direct effect of interannual and seasonal dynamics of water-level changes on observed vegetation patterns. In addition, progressive loss of hydrological connectivity and herbivory have been shown to massively affect macrophyte establishment and growth processes, especially in the very early stages of development and recovery of an impaired waterbody. Building on this evidence and delving into major international experiences in wetland restoration and enhancement, the aim is to outline the potential and limits of using macrophytes as nature-based solutions.