Fertilizer Use on Different Upland Cropping Systems for Soil Conservation in Yunnan
IPNI-1997-CHN-YN9
28 May 2001
1998 Annual Interpretive Summary
Fertilizer use on different upland cropping systems for soil conservation in Yunnan province, 1998
Ninety-four percent of the land area (383,390 km2) in Yunnan province is hilly, and 77 percent has a slope greater than 25 degrees. Soil erosion is a major problem because of concentrated rainfall events, heavy summer thunderstorms, geological structures with steep slopes, and improper farming practices. An integrated land management system comprised of contour alley cropping plus balanced fertilization was compared to the local farmer practice of downslope cultivation to evaluate soil, nutrient, and water losses as well as study economic viability. The balanced fertilization treatment included 276-70-70-5-15-78 kg/ha N-P2O5-K2O-zinc (Zn)-sulfur (S)-calcium (Ca) for corn and 152-38-150-40 kg N-P2O5-K2O S/ha in the subsequent wheat crop. The traditional practice was fertilized with 138 kg N/ha in the corn and 67 kg N/ha in the wheat crop. In 1998, results showed that the new technology increased yields in wheat and corn by 73 to 93 percent and 58 to 69 percent, respectively. Net income was raised by US$9.37 to 61.29/ha (wheat) and US$95.39 to 158.93/ha (corn). Furthermore, soil and nutrient losses were reduced to negligible amounts as compared to losses resulting from downslope cultivation. Contour alley cropping in combination with balanced fertilization appears most effective in reducing soil erosion and nutrient loss while increasing profits for farmers. Adoption of this technology is estimated to increase P and K consumption in Yunnan by 41 and 55 kg/ha, respectively. YUNNAN-09