Plant-based nature solutions for water quality and biodiversity

Nature-based solutions (NbS) such as Floating Treatment Wetlands (FTWs) and Constructed Wetlands (CWs) are increasingly recognized for their capacity to enhance water quality while simultaneously delivering ecological and aesthetic benefits. This work integrates findings from experimental and bibliometric studies on FTWs and CWs, aiming to advance understanding of their multifunctional roles in water and landscape management. Field experiments demonstrated that FTWs established in rural stormwater ponds support diverse microbial and macroinvertebrate communities, notably promoting plant growth–promoting bacteria and Odonata species, which completed their full life cycles within the systems. Complementary bibliometric analysis identified three major research fronts on FTWs: nutrient and pollutant removal processes, functional mechanisms within system components, and the ecological role of plants. Despite growing field-scale evidence, standardization in design, operation, and maintenance remains a critical research gap. In parallel, the implementation of a horizontal subsurface flow CW treating variable sewage loads in a mountain tourism facility in Portugal confirmed the robustness of these systems, achieving high removal efficiencies. Moreover, the use of ornamental polycultures enhanced aesthetics and biodiversity, demonstrating additional socioeconomic value. Collectively, these studies reinforce the potential of NbSs as sustainable ecotechnologies for decentralized wastewater treatment, phytoremediation, and biodiversity enhancement. Future research should focus on integrating ecological engineering, local materials, and citizen science approaches to optimize performance and scalability of these systems.