Management of Sloping Lands for Sustainable Agriculture in Sichuan
IPNI-1997-CHN-SC22
12 Jan 2005
2004 Annual Interpretive Summary
Management of Sloping Lands for Sustainable Agriculture in Sichuan, 2004
Several years of research and demonstration with balanced fertilization and biological barriers, also called alley cropping or eco-engineering, suggest a highly profitable and effective means of reducing soil erosion and improving crop yields per farmed hectare of sloping land.
In 2004, researchers further examined the effect of alley cropping on nutrient loss through water loss and soil erosion. Nutrient loss was positively correlated with water runoff. All patterns of alley cropping significantly reduced potassium (K), nitrogen (N), and phosphorus (P) losses. The impact on soil K loss was most significant... for example, Jianyang and Ziyang counties had 50 to 66% lower K losses than non-alley cropping techniques.
Hedgerow fruit trees have grown larger and their root systems have proliferated and invaded the field crop areas. This has begun to affect the growth and yield of field crops through their competition for nutrients and moisture. Overall crop yield was reduced by 16% after 7 years. This negative effect can be overcome by employing grasses such as common Eulaliopsis (a raw material for paper-making) or cash crops with relatively less extensive root systems such as honeysuckle (a Chinese herb) or perhaps an herbal tea crop.
Net income from the pear+daylily cropping pattern further increased by US$2,100 to US$2,500/ha, or 44% to 56% in Jianyang. All the other demonstration and extension sites have started to show gains in profit from the use of hedgerow crops. The Jianyang site received visitors nationwide and this successful story in soil conservation and farmer profitability is now well known. As a result, the Sichuan Government has stopped developing engineered terraces in the province in favor of this alley cropping technique. Sichuan-12A