Air quality has improved notably, with the average concentration of PM2.5 hazardous airborne particles decreasing from 46 micrograms per cubic meter in 2015 to 30 micrograms per cubic meter last year.
Days with good air quality accounted for 87.5 percent of 2021, up 6.3 percentage points from 2015 and making China the nation with the greatest air-quality improvement worldwide.
Over the past decade, the proportion of water at or above Grade III in the country's five-tier water quality system increased 23.3 percentage points to 84.9 percent, nearing the levels of developed countries.