Fig. 5

Temporal changes in HQ (A) and changes in the area of different grades of HQ (B) in mining urban agglomeration from 1990 to 2020. I: Worst; II: Poor; III: Moderate; IV: Good; V: Excellent.

Temporal changes in HQ (A) and changes in the area of different grades of HQ (B) in mining urban agglomeration from 1990 to 2020. I: Worst; II: Poor; III: Moderate; IV: Good; V: Excellent.