Effect of Chemical Fertilizers Application Combined with Organic Manure on Ammonia Volatilization in Spring in Apple Orchard

An experiment including six treatments,i.e.100%N,75%N+25%Y,50%N+50%Y,25%N+75%Y and 100%Y,was used to monitor ammonia volatilization using a venting method in upland apple orchard.The ammonia volatilization rate and losses amount were dramatically influenced by different fertilization cooperation.There were significant differences in the amount and appeared time about the peak of ammonia volatilization rate among different treatments,the peak appeared time in 100%Y was the earliest,the biggest peak of ammonia volatilization rate(2.07 kg N/(hm2·d)) was in 100% N.The highest gross amount of ammonia volatilization was in 100%N,reaching to 13.46 kg N/hm2,accounted for 3.46% of the N applied and was significantly higher than the values in other treatments;Both the gross amount of ammonia volatilization and the proportion of fertilizer application lost of applied N were lowest in 50%N+50%Y.Our study indicates that combination application of chemical fertilizer and organic manure could lower ammonia volatilization.