Fig. 6

Temporal trends of 15 social–environmental factors between 2007 to 2016. A PM2.5, (B) PM10, (C) SO2, (D) NO2, (E) O3, (F) NDVI, the number of days with (G) blowing sand (BS), (H) floating dust (FD), (I) haze, (J) sandstorms, (K) annual average temperature (TEMP), (L) the number of hospitals, (M) the number of medical beds (MedBeds), (N) the number of doctors, and (O) road area