From data to belonging: citizen science, urban friction, and institutional response in Siena

This article examines citizen science as situated urban politics inSiena, Italy, through two initiatives engaging students, residents,migrants, volunteers, and researchers in documenting everydayurban life and river ecosystems. Drawing on ethnographic engage-ment, data walks, and interviews, we argue that citizen scienceproduces more than data: it becomes a relational practice throughwhich participants negotiate belonging, enact presence, and chal-lenge epistemic hierarchies in urban governance. The articleshows how digital platforms both enable participation and act asepistemic gatekeepers, making friction a diagnostic and transfor-mative force for more responsive urban knowledge practices.