Water soundscapes: a systematic review on trends, current challenges, and research gaps

Water soundscapes are increasingly recognized as critical components of urban environments, contributing to acoustic comfort, restoration, and environmental perception. Beyond their traditional role in noise masking, water sounds operate as perceptually and contextually mediated auditory resources embedded within urban experiences. This systematic review synthesizes water soundscape research to identify trends, methodological developments, and persistent research gaps relevant to sustainable urban design. Using a Searching, Appraisal, Synthesis, and Analysis (SALSA) framework, 61 peer-reviewed studies published between 2005 and December 2024 were selected from an initial pool of 2457 records. The synthesis reveals a disciplinary transition from acoustics-led, sound-level-based approaches toward perception-oriented frameworks aligned with the ISO 12913 soundscape paradigm. Evidence indicates that psychoacoustic attributes, temporal variability, contextual fit, and audio-visual coherence explain human preference, restoration, and annoyance more robustly than sound pressure level alone. Integrative mixed-method approaches, combining soundwalks, psychoacoustic analysis, immersive virtual environments, and physiological indicators, emerge as state-of-the-art, although methodological heterogeneity constrains cross-study comparability. The review further identifies geographical concentration, limited ecological integration, and weak translation into planning and design practice as key challenges. Future research should prioritize standardized and context-sensitive approaches globally.