The reasons for the increasingly serious pollution of Weihe River include three aspects: first, urban domestic sewage and garbage; The second is industrial wastewater; Third, there is a serious shortage of ecological water.
The pollution factors of Weihe River include chemical oxygen demand, ammonia nitrogen and petroleum, heavy metals such as lead, hexavalent chromium, arsenic, cadmium and mercury, and the main pollutants are COD. According to the Class IV standard of Weihe River exit water required by the state, the environmental capacity of Weihe River is 70,000 tons of COD per year. However, in 2004, the actual discharge of COD in Weihe River Basin exceeded 270,000 tons, accounting for more than 80% of the total discharge in the province, which was about 3 times higher than the environmental capacity. According to industry statistics, papermaking is the biggest polluter, along with beverage industry, textile industry, chemical industry, agricultural and sideline food processing industry, wood processing industry, pharmaceutical manufacturing industry and oil and gas industry.
Since 1970s, the annual runoff of Weihe River Basin has been decreasing year by year. After the 1990s, the average annual runoff was less than 7 billion cubic meters, only about half of that in the 1960s. However, the national economic water consumption in Weihe River Basin has been increasing continuously, from 28 cubic meters per year before 1990s to 4.3 billion cubic meters per year after 1990s, and it is still increasing year by year. The Weihe River's annual inflow into the Yellow River is less than half that of the past, only 4 billion cubic meters. According to the current water consumption, the annual output of Weihe River is 120 billion cubic meters, which can meet the basic needs of national economic water and ecological water. In other words, the Weihe River lacks more than 5 billion cubic meters of water; Serious water shortage leads to insufficient irrigation water, over-exploitation of groundwater and extreme shortage of ecological water.
Present situation of water quality:
The monitoring results in 2005 show that there are 13 routine monitoring sections in the main stream of Weihe River. According to the Environmental Quality Standard for Surface Water (GB3838-2002), the water quality is Class II 1, Class III 1, Class IV 2, and Class V 9. ..
Our government published a white paper on environmental protection on 1965 World Environment Day Day. As can be seen from this white paper, ecological protection in China, especially water environment protection, still faces many problems. Although the efforts to protect the water environment have been increasing in recent years, the deterioration trend of river water quality has not been effectively curbed. Today we will pay attention to the Weihe River in Shaanxi.
Our government published a white paper on environmental protection on 1965 World Environment Day Day. As can be seen from this white paper, ecological protection in China, especially water environment protection, still faces many problems. Although the efforts to protect the water environment have been increasing in recent years, the deterioration trend of river water quality has not been effectively curbed. Today we will pay attention to the Weihe River in Shaanxi.
This river is the largest tributary of the Yellow River, and it is called the "mother river" of Guanzhong Plain because it is rich in aquatic plants in history. But now the Weihe River is called "abandoned river" by Shaanxi people, because most of the river basin water can't be drunk and used. The mother river turned into an abandoned river, which made a Guanzhong man who grew up drinking Weihe River very sad. He recorded the process of this change with his own lens.