China has insufficient water resources. The amount of fresh water available per capita is about one-quarter of the global average of 8513 m3 per year (2002 statistics; World Bank 2003). In a survey of more than 600 Chinese cities, two-thirds had inadequate water supplies, while 1 in 6 experienced severe water shortages (Li 2003). Water pollution caused by rapid urbanization and the formation of city clusters has exacerbated the lack of accessible drinking water. While levels of industrial wastewater discharge have largely stabilized, domestic wastewater has increased considerably. While the total amount of released industrial wastewater fluctuated around 22 billion tons from 1995 to 2004, the domestic sewage discharge increased from 13.1 billion tons in 1995 to 22.1 billion tons in 2000, and up to 26.1 billion tons in 2004 (State Environmental Protection Administration [SEPA] 1995–2004). This was due primarily to the enactment of more stringent controls on industrial sources of wastewater; in 2003, 91% of industrial wastewater was treated, in contrast to only 32% of urban domestic sewage (National Bureau of Statistics 2004).
As a consequence, surface water quality has become an issue of great concern in China. A national survey of seven major rivers in China, carried out in 2004, revealed that water quality measurements in 28% of 412 monitored sections were below grade V, the worst grade in the national standard for water quality in China. These results indicate that, for these sections of river at least, the water supply is virtually of no practical or functional use, even for agricultural irrigation. For the Haihe River, which provides the cities of Beijing and Tianjin with the bulk of their drinking water, this figure was as high as 57%, and for the Liaohe River, which supplies water to Northeast China, it was 38% (see Figure 2 for the locations of these rivers). Overall, more than 90% of the river sections that flowed through urban areas showed a water quality of grade V or worse (SEPA 1995–2004). The higher the grade, the worse the water quality; only water with a grade lower than III is drinkable. The same survey suggested that even the water quality of the Yangtze and Pearl Rivers, both of which have relatively abundant water flow, was a cause for concern; approximately 10% of the monitored sections of these two rivers also revealed water quality worse than grade V, and all monitored sections in the urban area of Guangzhou (on the Pearl River) had water quality around grade V or worse. The water quality of the rivers shown in Figure 2 was characterized only by conventional indicators, such as chemical oxygen demand (COD), ammonia, and volatile phenols, among others. The situation is even more worrisome when endocrine disrupting organic substances are taken into consideration as well (An and Hu 2006).
ประเทศจีน มีแหล่งน้ำไม่เพียงพอ ปริมาณน้ำใช้ต่อหัวประมาณหนึ่งในสี่ของค่าเฉลี่ยทั่วโลกของ 8513 m3 ต่อปี ( สถิติของธนาคารโลก 2545 ; 2546 ) ในการสำรวจของกว่า 600 เมืองจีน สองในสามมีแหล่งน้ำเพียงพอ ในขณะที่ 1 ใน 6 ประสบการขาดแคลนน้ำอย่างรุนแรง ( หลี่ 2546 ) Water pollution caused by rapid urbanization and the formation of city clusters has exacerbated the lack of accessible drinking water. While levels of industrial wastewater discharge have largely stabilized, domestic wastewater has increased considerably. While the total amount of released industrial wastewater fluctuated around 22 billion tons from 1995 to 2004, the domestic sewage discharge increased from 13.1 billion tons in 1995 to 22.1 billion tons in 2000, and up to 26.1 billion tons in 2004 (State Environmental Protection Administration [SEPA] 1995–2004). This was due primarily to the enactment of more stringent controls on industrial sources of wastewater; in 2003, 91% of industrial wastewater was treated, in contrast to only 32% of urban domestic sewage (National Bureau of Statistics 2004).
As a consequence, surface water quality has become an issue of great concern in China. A national survey of seven major rivers in China, carried out in 2004, revealed that water quality measurements in 28% of 412 monitored sections were below grade V, the worst grade in the national standard for water quality in China. These results indicate that, for these sections of river at least, the water supply is virtually of no practical or functional use, even for agricultural irrigation. For the Haihe River, which provides the cities of Beijing and Tianjin with the bulk of their drinking water, this figure was as high as 57%,และแม่น้ำ liaohe ซึ่งวัสดุน้ำภาคตะวันออกเฉียงเหนือของประเทศจีน เป็น 38 % ( ดูรูปที่ 2 สำหรับที่ตั้งของแม่น้ำเหล่านี้ ) โดยรวมแล้ว มากกว่า 90% ของแม่น้ำส่วนที่ไหลผ่านเขตเมือง พบว่าคุณภาพน้ำของนักเรียนชั้นประถมศึกษาปีที่ 5 หรือแย่ลง ( เสภา 1995 – 2004 ) สูงกว่าเกรด ด้อยคุณภาพน้ำ แต่น้ำที่มีเกรดต่ำกว่าสามจะดื่มได้การสำรวจเดียวกันพบว่าคุณภาพน้ำของแม่น้ำ แยงซี และไข่มุก ซึ่งทั้งสองมีค่อนข้างมากมาย น้ำไหล เป็นสาเหตุสำหรับกังวล ; ประมาณ 10% ของการตรวจสอบส่วนของทั้งสองแม่น้ำพบคุณภาพน้ำแย่กว่าเกรด V และตรวจสอบ ส่วนในพื้นที่เมืองของกว่างโจว ( บน แม่น้ำไข่มุก ) มีคุณภาพน้ำรอบๆเกรด V หรือแย่ลง The water quality of the rivers shown in Figure 2 was characterized only by conventional indicators, such as chemical oxygen demand (COD), ammonia, and volatile phenols, among others. The situation is even more worrisome when endocrine disrupting organic substances are taken into consideration as well (An and Hu 2006).
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