The recent invention of nitrogen fixation for trees has made it possible for the muddy Yangtze River to become clear again.
The 8-year Experiments have shown that shelterbelts of three- year-old nitrogen fixation trees can reduce soil erosion by 98 percent, according to Prof. Chen Keming of the Chengdu Biological Research Institute of the Chinese Academy of Sciences.
The branches and leaves of the trees can be used as green manure or forage. One ha of nitrogen fixation plants, for example, can produce 10 tons of high-quality green manure annually.
With this technology, local soil erosion can be effectively brought under control, and the Yangtze River will become clear again, as soil erosion on the upper reaches of the Yangtze is the major cause of the turbidity of its water, Chen said.
"It is a practical technology that involves less investment while bringing more benefits," he said, adding that farmers would be likely to accept the new technology as it can better preserve soil and raise their incomes.
Now, the invention has been put into use in some counties of Sichuan Province, where the institute has set up a base of 4,000 ha of nitrogen fixation plants.
"If the technology is applied to the 11 million ha of slopes along the upper reaches of the Yangtze, the river will be safe from soil erosion," Chen said.