BEIJING, March 30 (Xinhua) -- A major environmental clean-up effort is being waged in the provinces and regions along the Yellow River.

　　One of these provinces, Gansu, an inland northwestern province on the upper reaches of the river, will invest 4.97 billion yuan (612.8 million U. S. dollars) during the 11th Five-Year Plan (2006-10) to control pollution and improve river conditions, according to the province's environment protection authority.

　　The Gansu section of the Yellow River stretches 913 kilometers over four cities and prefectures. The cities of Lanzhou, capital of the province, and Baiyin, both have a high density of heavy industries discharging large quantities of pollutants into the river, said Yang Zhiming, vice-governor of Gansu Province, as quoted by Thursday's China Daily.

　　Added to this is some 237 million tons of sewage from the province, which is pumped into the river each year, with only 34 percent of it receiving proper treatment.

　　The 4.97 billion yuan will be used for 199 environmental projects in Gansu to assist heavy industries in decreasing industrial pollutants, construction of urban sewage treatment plants and the installation of supervision facilities to protect the environment and ensure better water quality by 2010, Yang said.

　　Following the Yangtze River, the Yellow River is the second longest in China, spanning 5,464 kilometers across nine provinces and regions from Qinghai Province in Northwest China into the eastern Bohai Sea in Shandong Province.

　　It covers 752,000 square kilometers, an area populated by more than 146 million people, or 11.5 per cent of China's total population, according to official statistics.

　　Rapid economic development and a growing urban population over the past 30 years has taken its toll on the river. Without adequate resources, pollution has worsened and measures to protect and improve the river have not been taken effectively, said Luo Yongfu, environment expert and professor at Chang' an University in Xi'an, capital of Shaanxi Province.

　　Luo called for a collaborative effort by all provinces and regions along the river to control pollution.

　　"Otherwise, the improved section along the lower reaches of the river may again be contaminated by pollutants from the upper reaches," Luo said.

　　Gansu's neighboring province, Shaanxi, located in the middle reaches of the river, also plans to curb pollution in its Weihe River, the largest tributary of the Yellow River.

　　The Weihe River is the only channel for industrial waste and sewage in central Shaanxi, according to He Fali, director of Shaanxi Provincial Environmental Protection Department.

　　"Every year, the Weihe River receives 800 million tons of industrial and urban sewage, one of the major pollution sources of the Yellow River," He said.

　　The Shaanxi government will pour 4.5 billion yuan (US$554.8 million) over five years into cleaning up the Weihe River. It plans to construct sewage treatment facilities, adjust industrial waste infrastructure, develop ecological agriculture and high-tech industries, and further protect surface and underground water resources.

　　Similar measures and plans are in train for other provinces and regions -- the Inner Mongolia Autonomous Region, Shanxi and Henan provinces in the river's middle reaches, and Shandong Province in its lower reaches. Enditem