The Department of Ecology and Environment of Anhui Province released rankings of quality of surface water of 16 cities in Anhui during the first two months this year, with Huangshan, Chizhou and Tongling among the top three.
Meanwhile, Lu’an made the biggest year-on-year improvement in water quality, followed by Bengbu and Huaibei.
The rankings are determined by water quality index. The smaller the index is, the better the water quality is. The index is based on 21 indicators including PH, dissolved oxygen,and ammonia nitrogen.
Rankings reveal conditions about water quality compared to the same period last year in cities according to the rate of change in water quality index. The rate of change greater than zero represents a decline, the rate equal to zero represents a flat and the rate less than zero represents an improvement.
Statistics show that the change rates of water quality index in Huangshan, Anqing, Ma’anshan, Bozhou, Wuhu and Fuyang were greater than zero, while those in the remaining cities were smaller than zero.
Lu’an boasted the greatest surface water quality improvement, which reached 17.18 percent.