Analysis of Water Environment Quality Changes and Influencing Factors during the "Thirteenth Five-Year Plan" Period in Heilongjiang Province

Heilongjiang Province is located in the northeastern part of China and is the province with the highest latitude in China. As Heilongjiang Province is the most important grain production base in China, the Chinese government attaches great importance to the quality of the ecological environment in Heilongjiang Province, especially the analysis of changes in the quality of the water environment and their driving factors. We studied the changes in the environmental quality of surface water in Heilongjiang Province during the "13th Five-Year Plan" period (2016-2020), and analyzed the surface water for four major pollutants including the permanganate index, chemical oxygen demand, ammonia nitrogen and total phosphorus, and the change trends of the proportion of the water quality of class I-III and the proportion of the water quality of inferior class V. The results show that the environmental quality of surface water in Heilongjiang Province has improved significantly during the "13th Five-Year Plan". The analysis of the driving factors of the change of surface water environment quality shows that the population, the primary industry, the tertiary industry and forestry are the main factors affecting the change of water environment quality in Heilongjiang Province.