Nutrient management and high efficient fertilization on main crops in Beijing

IPNI-2009-CHN-BJ12

26 Feb 2010

2009 Annual Interpretive Summary


Optimized Nitrogen Nutrient Management for Vegetables in Beijing, 2009

Over-fertilization is of great concern for the vegetable production area immediately surrounding Beijing. Field trials and demonstrations Over-fertilization is of great concern for the vegetable production area immediately surrounding Beijing. Field trials and demonstrations were conducted in 2009 to determine optimal N rates for important vegetables grown within the region. Different N application rates, including 0, 90, 180, 270, 360, and 450 kg N/ha were applied on greenhouse tomatoes located in Dasunge Village of Shunyi. Farmers typically apply 450 kg N/ha, but no yield differences were apparent as N rates decreased to 270 kg N/ha. Additionally, use of 270 to 360 kg N/ha reduced surface (0 to 20 cm) soil nitrate concentrations by 31.7 to 69.3% and nitrate accumulation in the top 100 cm depth could be reduced by 28 to 49%. A separate open field experiment was conducted on Chinese cabbage in Xiaofengying Village of Yanqing County. Results showed that yield was not significantly affected as N application rate fell from 450 kg/ha (farmers’ rate) to 315 kg/ha. Nitrate concentration was also reduced with N rate.

This initial data suggest that farmers could rely on lower N rates without suffering yield losses, and the potential risk to the environment could also be decreased. Results from the first year of experimentation, both under greenhouse and open field study, indicate that vegetable yields were not affected as N rate was reduced by 30 to 40%. Beijing-NMBF