At Chaotianmen (Gate facing the sky) Wharf in southwest China's Chongqing Municipality, the limpid water of the Jialing River meets and distinguishes itself sharply from the turbid stream of the Yangtze River. Nevertheless, Su Zhixian, an ecological professor, warned recently that the silt content of the Jialing River now ranks first among all the branches of the Yangtze River, which seriously threatens the ecological safety of the Three Gorges Reservoir Area and the lives of riverside residents.

Su, chairman of the executive council of the Sichuan Ecology Society and the vice president of the Sichuan Teachers College, is now in charge of several research programs funded by the National Natural Science Foundation and the "973 Program". Five years ago, he headed a research team to investigate soil erosion and environmental pollution in the Jialing River Valley.

As the second largest branch of the Yangtze River, the Jialing now annually produces 1.7 million tons of silt accounting for 30 percent of the total annual silt flux passing the Yichang Hydrology Station of the Yangtze River in Hubei Province. And about 52 percent of the soil in the valley along the Jialing River's downstream sector from Hechuan Country to Chaotianmen Wharf has been moderately eroded, representing 26 percent the total area of dry fields in Chongqing, according to Su.

He attributed the severe soil erosion to geological and meteorological conditions as well as human activities, which include deforestation, land reclamation, and destruction of vegetation and water systems.

In the 1940s, forests covered over 20 percent of the Jialing River Valley, while today the figure has dropped to less than 10 percent, Su said, adding a warning that the present situation might develop to a very serious degree.

As a lifeline for people in Sichuan and Chongqing, the Jialing River would become a second Yellow River if local governments and researchers do not take pertinent actions promptly, he said.

He is urging more efforts to curb the pollution and strengthen environmental preservation along the River.

"To protect the Jiangling River Valley, we should adopt comprehensive strategies involving engineering, biological and agricultural measures."

(china.org.cn by Chen Chao, June 25, 2002)