The interactive effects of water and nitrogen addition on ammonia volatilization loss and yield of winter wheat.

Abstract

An experiment with winter wheat of Shimai 15 and treatments of two types of fertilizers (organic manure, M; urea, U), two amounts of nitrogen application (180 kg·hm-2, M1U1; 90 kg·hm-2, M2U2), two irrigation levels (500 mm, W1; 250 mm, W2) was carried out in the lysimeters in 2015-2017. The results showed that ammonia volatilization was substantial after fertilization and irrigation. The dynami of ammonia volatilization during two years was similar. The process of ammonia volatilization after fertilization lasted for seven days. In 2015-2016, the total amount of ammonia volatilization ranged from 13.36 to 46.04 kg·hm-2, and the loss rate of ammonia nitrogen ranged from 8.9% to 41.1%. The total amount of ammonia volatilization in 2016-2017 ranged from 14.78 to 52.99 kg·hm-2, and the ammonia nitrogen loss rate ranged from 9.2% to 45.8%. During the two years, the highest loss of ammonia volatiles occurred in W2U1, the highest loss rate of ammonia volatilization occurred in W2U2. Ammonia volatilization loss rate significantly decreased under appropriate water and nitrogen management. Ammonia loss under the application of urea was about 2-3 times of organic manure. The highest yield occurred in W1M1 during the two growing seasons. The type of fertilizer, the amount of irrigation and nitrogen applied interactively affected the yield of winter wheat. As for the increases of production, organic manure was better than urea. Under the experimental condition, the best treatment was irrigation amount of 500 mm and application of organic manure with about 180 kg·hm-2 of N fertilizers, which could be applied in practice for wheat production in Huang-Huai-Hai region.