“…Specifically, water quantity regulation services mainly include runoff volume reduction, peak flow reduction, and time-to-peak delay, while water quality regulation services are mainly the removal of TN, TP, COD, TSS, etc. Nevertheless, relevant GSI planning research involves disparate planning steps, e.g., Koc et al [32] evaluate GSI scenarios to select the best one based on identifying the planning objective as runoff reduction; in contrast, Zhang et al [33] directly assess the suitability of GSI construction without clearly setting out the planning objective, while Li et al [34] put forward the planning objectives clearly as a 20% annual comprehensive runoff coefficient, evaluated the scenarios through SWMM and SUSTAIN, and calculated the construction area of GSI. Therefore, GSI planning may involve objective formulation, type/scenario evaluation, site selection, etc., which are given different considerations in different planning strategies.…”