Welcome to Chinese Agricultural Science Bulletin,

Chinese Agricultural Science Bulletin ›› 2023, Vol. 39 ›› Issue (24): 24-30.doi: 10.11924/j.issn.1000-6850.casb2022-0725

Previous Articles     Next Articles

Optimized Nitrogen Fertilizer Management for Maize in Beijing under Different Soil Fertility Levels

ZHAO Kaili1(), LI Quanhui2, LIU Yu1, LI Ping1, CHEN Juan1, YAN Fang1, YAN Shi1, GUO Ning1()   

  1. 1 Beijing Cultivated Land Construction and Protection Center, Beijing 100101
    2 Beijing Miyun Soil Fertilizer Extension Service Station, Beijing 101500
  • Received:2022-08-22 Revised:2022-11-23 Online:2023-08-25 Published:2023-08-23

Abstract:

We conducted a field experiment of maize under different soil fertility levels. The effects of different nitrogen application rates on maize yield, recovery efficiency of N and N uptake were studied. By comparing yield, recovery efficiency of N, the recommended nitrogen application rate was integrated to reduce the environmental risks of soil nitrogen caused by excessive fertilizer input. The experiments were under high, medium and low soil fertility levels, and there were four nitrogen (N) treatments, including no fertilizer (N0), recommended fertilization (OPT), low nitrogen application (N50, 50% of N rate based on OPT) and high nitrogen application (N150, 150% of of N rate based on OPT). The maize yields, N uptake, recovery efficiency of N were measured. The nitrogen application rate, yield and recovery efficiency of N were respectively compared when the curves reached the theoretical maximum, the recommended nitrogen application rates of high and medium fertility farmland were obtained comprehensively. The results showed that the maize yields of different soil fertility levels were in the order of high fertility field > medium fertility field > low fertility field. Contribution of inherent soil productivity had the same trend. OPT had the highest yield among all treatments, the yield of high fertility field was 11865.2 kg/hm2, which was 19.3% higher than that of N0, the yield of medium fertility field was 11458.4 kg/hm2, 29.6% higher than that of N0, and the yield of low fertility field was 10163.1 kg/hm2, 43.0% higher than that of N0. By fitting the quadratic curve between yield and N application rate, it was found that increasing N application rate in low fertility field could not achieve the yield of high fertility field. Improving the soil fertility of low fertility field was more necessary. The N uptake under different soil fertility levels was followed: high fertility field > medium fertility field > low fertility field (except OPT treatment under medium fertility field). The recovery efficiency of N, N uptake, OPT was higher than that of other treatments. Among them, recovery efficiency of N of medium fertility field was 35.8%, higher than that of low fertility field (27.0%), and high fertility field (24.8%). By comparing the N application rate, yield, recovery efficiency of N when the theoretical yield and the theoretical recovery efficiency of N reached the maximum, it was concluded that the yield could be increased in medium fertility field by increasing N application rate when differential of recovery efficiency of N was small, the recommended N application rate was 162.4 kg/hm2. By small differential of yield, N application rate should be controlled to improve the recovery efficiency of N in high fertility field, the recommended N application rate was 143.3 kg/hm2.

Key words: contribution of inherent soil productivity, N application rate, recovery efficiency of N, maize yields