Using a fractional order grey seasonal model to predict the dissolved oxygen and pH in the Huaihe River.

To accurately forecast the seasonal fluctuations of dissolved oxygen (DO) and pH in Huaihe River, a grey seasonal model with fractional order accumulation is proposed, optimized by particle swarm optimization (PSO-FGSM(1,1)). We use this new model to carry out an empirical analysis based on the DO and pH data from 2014 to 2018 from Huaibin, Bengbu, Chuzhou monitoring points. The comparison results show that the PSO-FGSM(1,1) model accuracy is significantly higher than the Holt-Winters model with grey wolf optimization (GWO-Holt-Winters). The prediction results indicated that the pollution of the Huaihe River has regional characteristics. The Huaibin and Chuzhou sections of the Huaihe River are slightly polluted, and the Bengbu section is seriously polluted.