Abstract:In order to improve the nitrogen use efficiency and reduce the resource waste and the risk of environmental pollution, a study on the leakage loss of controlled release nitrogen fertilizer (CRNF) application in hilly area of South China was conducted. The effects of CRNF (T3~T6) application on nitrogen dynamics and loss of TN,NO3-—N and NH4+—N in leachate water under different treatments in Spring Maize soil were explored. The results showed that the leakage water was 3 888.40~3 948.69 L when the nitrogen application rate was 168~240 kg N/hm2, hence fertilizer application rate had no significant effect on the leakage volume (P>0.05). Average leaching loss concentration of TN, NO3-—N and NH4+—N under T3 treatment were as follows 32.66 mg/L, 29.41 mg/L, and 0.26 mg/L. Compared with the application of common urea (T2), T3 treatment with the same amount of nitrogen application rate decreased by 24.99% (P<0.01), 25.56 % (P<0.01) and 25.71 % (P<0.05), respectively. Meanwhile, the loss load decreased by 24.10 %( P<0.01), 25.62 %( P<0.01) and 18.97 %(P>0.05), respectively, and namely 53.07, 47.14 and 0.47 kg N/hm2. When the nitrogen fertilizer application rate was reduced by 10 %, 20%, 30%, the corresponding average TN loss concentration were 28.81, 26.50 and 24.34 mg/L, which decreased by 11.79%(P>0.05), 18.86%(P<0.05), 25.47%(P<0.05)compared to T3. Similarly, the loss load were 41.78, 36.62, and 33.90 kg N/hm2, which decreased by 21.27%(P<0.01), 31.00%(P<0.01), 36.12(P<0.01), respectively. NO3--N is the major component of leakage nitrogen loss, which accounted for 88.83%~92.75% of TN loss load, and DON was also not negligible. During the planting of Spring Maize in dry land, the CRNF application rate with 192 kg/hm2 could effectively reduce the loss of nitrogen leaching and the risk of environmental pollution, and even increase yield and efficiency.