Nutrient Management Strategies for Yunnan

This monitored village study in Qujing and Songmin counties, which represent typical grain and grain-tobacco farming areas in Yunnan province, is tracking variability in soil fertility and providing information from field trials and fertilizer use surveys to populate the PPI/PPIC China Program Soil Fertility Information Database. The final objective is to develop a proper soil nutrient management system to support rational fertilization.

Results show that soil nutrient status varied considerably in the two villages, and the variation was closely related to the particular cropping system and historical fertilization practices. In the major tobacco growing area, soils were mainly deficient in nitrogen (N), magnesium (Mg), and boron (B). Available phosphorus (P) and potassium (K) were relatively high due to farmer reliance on heavy topdressing of P and K nutrients to pursue high economic returns. The major grain growing area soils were deficient in N, P, and K.

This study elucidates the major causes for soil nutrient variability in these two villages and offers scientific guidance for proper nutrient management in these important cropping systems. YUNNAN-NMS01