Management of Sloping Lands for Sustainable Agriculture in Sichuan

The objective of this study is to evaluate a new approach of using balanced fertilizer and biological barriers on sloping lands rather than expensive mechanical terracing to effectively and profitably reduce soil erosion. Erosion is the major source of flooding in the Yangtze River and is a primary cause of farmer poverty.

During 1998-1999, this new technique showed significantly reduced soil loss and improved farmer income. This project was highly evaluated by farmers and provincial and county governments and may become a national model for profitably reducing soil erosion. In 2000, alley cropping reduced crop yield by 692 kg/ha, or 8.1 percent, but it also reduced soil loss from 9.4 to 4.5 t/ha, or 52 percent, and increased net income by US$210/ha. The integration of alley cropping with balanced fertilization applications of 160-120-150 kg N-P₂O₅-K₂O/ha for corn, 60-60-65 kg for sweet potato, and 150-75-120 kg for wheat and barley reduced crop yield by 240 kg/ha, or 2.9 percent, but improved net income by US$336/ha and reduced soil loss by 57 percent.

It is obvious that the effects of biological barriers of cash crops are becoming more significant with time. The new technology can be applied on 240,000 ha of sloping lands in Sichuan province and neighboring Chongqing province. In 2000, this technique was extended on five additional hectares in Jianyang, and the story was broadcast on Sichuan television several times. SICHUAN-12A