Abstract:Taking the acrossocheilus labiatus in the Sheyang River of Longyou County, Zhejiang Province as the representative fish, a habitat suitability model was established by using GAM and HSI models through the investigation of fish communities and possible habitat impact factors in the field from 2017 to 2020. The habitat suitability zoning and threshold range were analyzed. The results show that the arithmetic mean algorithm (AMM) for weighting GAM models has the best model fitness. Flow rate, chlorophyll a and water depth are the key explanatory variables of the habitat suitability index model, and their deviation contribution rates are 61.5%, 21.0% and 12.5%, respectively. The optimum flow rate is from 37 to 58 cm/ s, the optimum water depth is from 40 to 63 cm, and the optimum chlorophyll a is from 0. 10 to 0. 35 mg/ m3. The habitat zoning of the acrossocheilus labiatus has strong spatial-temporal differences. The optimum habitat is mainly distributed in the upper and middle reaches of the river while the habitat suitability significantly deteriorated in 2019 and 2020.